In the drive towards environmental restoration and sustainable energy solutions, effective utilization and management of agricultural crop residues are vital to mitigate greenhouse gas (GHG) emissions and waste accumulation. Converting biogenic wastes into biofuels and bioproducts has the potential to tackle the energy crisis and contribute to environmental remediation. In this investigation, teff husk, primarily generated in Ethiopia during teff production within the agro-industrial sector, is used as the feedstock for the slow pyrolysis process. In Ethiopia, it is estimated that over 1.75 million tons of teff husk are generated annually, with a significant portion being incinerated in the fields, resulting in substantial environmental pollution. This study focuses on assessing teff husk as a potential material for slow pyrolysis, a crucial stage in biochar production, to tap into its biochar-producing potential. To determine the composition of the biomass, the teff-husk was initially analyzed by thermogravimetry. The significant presence of fixed carbon indicates that teff husk is a viable candidate for pyrolytic conversion into biochar particles. The process of slow pyrolysis took place at three varied temperatures—specifically, at 400, 450, and 500 °C. Process parameters of slow pyrolysis such as reaction time, temperature, and heating rate were enhanced to obtain maximum biochar yields. The highest biochar yield of 43.4 wt% was recorded at optimized reaction time, temperature, and heating rate of 120 min, 400 °C, and 4.2 °C/min, respectively. Furthermore, biochar's physicochemical, SEM-EDX, FTIR, and TGA characterization were performed. The thermal stability and carbon content of biochar were found to rise at higher temperatures. Unlike fuel recovery, the results suggest that teff-husk can be used as a feedstock for biochar production.

In this study, the properties of unsaturated polyester resin were studied in the presence of recycled ceramic waste particles. Herein, composites were created that contained 28.5-50 wt% porcelain particles (particle size <180 µm). High filler contents increased the gel time and decreased the exotherm temperature of unsaturated polyester resin during curing. The obtained results showed that physical parameters, such as the resin density and porosity, increased as the filler content increased. In addition, the X-ray diffraction results indicated that the produced samples were a combination of ceramic waste particles and unsaturated polyester resin, resulting in semi crystalline structure. The results showed that the maximum water absorption at 40°C increased from 0.97 to 1.5% as the filler content increased from 28.5 to 50 wt%; in this process, the materials experienced a color change but did not lose mechanical performance. Finally, the samples were characterized by thermogravimetric analysis (TGA) to study the effect of porcelain powder on the thermal degradation of the resin. The TGA scans were analyzed with the Friedman method. The results indicated that the samples with porcelain powder exhibited substantially better thermal stability than unsaturated polyester resin.

The beneficial effects of Lanthanide incorporation into 0.94Na0.5Bi0.5TiO3-0.06BaTiO3 (BNT-BT) matrix on its functional properties were investigated. The conventional solid-state method was used for synthesizing samples. The structural refinement revealed that all samples crystallized in R3c rhombohedral symmetry. Raman spectroscopy study was carried out using green laser excitation and revealed that no clear perceptible variation in frequency is observed. Dielectric measurements unveiled that the introduction of rare earth obstructed the depolarization temperature promoted in BNT-BT with decreasing the diffusive phase transition with increasing the lanthanide size. Only Dysprosium addition showed comparable diffusion constant and dielectric behavior as the unmodified composition. Further, the comparison of the obtained ferroelectric hysteresis and strain-electric field loops revealed that only Dy-phase exhibited interesting properties comparing parent composition. In addition, the incorporation of lanthanides Ln3+ into the BNT-BT matrix led to the development of luminescence characteristics in the visible and near infrared regions, depending on the excitation wavelengths. The simultaneous occurrence of photoluminescence and ferroelectric/piezoelectric properties opens up possibilities for BNT-BT-Ln to exhibit multifunctionality in a wide range of applications.Keywords: Sodium Bismuth Titanate; structural refinement; dielectric properties; ferroelectric properties; piezoelectric properties; Photoluminescence.

Improper disposal of waste plastic has caused serious ecological and environmental pollution problems. Transforming plastics into high value-added chemicals can not only achieve efficient recycling of waste plastics, but also an effective way to control white pollution. The catalyst selectively breaks the C-C bond of polyolefin plastic under heat treatment and converts it into liquid fuel, thus realizing sustainable recycling of plastics and has a good development prospect. This review provides a detailed overview of the current development of catalytic pyrolysis, catalytic hydrolysis, solvent decomposition and supercritical hydrothermal liquefaction for cracking plastics to make fuel oil. The reaction mechanism, influencing factors and promoting effects of catalysts in various degradation technologies are analyzed and summarized and the latest proposed tandem reaction for degrading plastics is briefly introduced. Finally, some optimization paths of waste plastic pyrolysis to fuel oil technology are proposed: synergies between mixed raw materials, in-depth exploration of catalysts, design and manufacture of reactors that match the pyrolysis technology. All these are important research directions for promoting the industrialization of plastic pyrolysis to fuel oil.

The aim of this study was utilization of ground tea waste (GT) left after brewing the black tea as a biofiller of natural rubber (NR) composites. Ionic liquids (ILs), i.e., 1-ethyl-3-methylimidazolium lactate and 1-benzyl-3-methylimidazolium chloride, often used to extract phytochemicals from tea, were applied to improve the dispersibility of GT particles in elastomeric matrix. The influence of GT loading and ILs on curing characteristics, crosslink density, mechanical properties, thermal stability and resistance of NR composites to thermo-oxidative aging was investigated. The amount of GT did not significantly affect curing characteristics and crosslink density of NR composites, but had serious impact on tensile properties. Applying 10 phr of GT improved the tensile strength by 40% compared to unfilled NR. Further increasing in GT content worsened the tensile strength due to the agglomeration of biofiller in elastomer matrix. ILs significantly improved the dispersion of GT particles in elastomer and increased the crosslink density by 20% compared to the benchmark. Owing to the poor thermal stability of pure GT, it reduced the thermal stability of vulcanizates compared to unfilled NR. Most importantly, GT-filled vulcanizates showed improved resistance to thermo-oxidative aging, since the aging factor increased by 25% compared to the unfilled vulcanizate.

Silica fly ash, Certyd aggregate, and an alkaline solution were used to produce lightweight geo-polymer concretes. The compressive strength, water absorption, bulk density and SEM photos showing the structure of the obtained composite were carried out. Tests conducted on the specifi-cation of lightweight geopolymer concretes have revealed significant chemical interactions between the ash aggregate and the geopolymer mortar, particularly when the coarse aggregate surface has been pre-treated with an alkaline solution. Statistical analysis of the experimental data, which in-vestigated the influence of three key variables on compressive strength, water absorption, and bulk density of Lightweight Geopolymer Concrete (LBG), identified the following factors as having the most substantial impact: the quantity of alkali used, the curing temperature, and the concentration of alkali in the mixture. The optimal test series exhibited a commendable compressive strength of 20.14 megapascals (MPa), accompanied by a water absorption rate of 14.72% and a bulk density of 1486.6 kilograms per cubic meter (kg/m³). These findings underscore the importance of alkali con-tent, curing temperature, and alkali concentration in tailoring the properties of lightweight geo-polymer concrete to meet specific performance requirements.

In an attempt to reuse fibrous textile waste and, at the same time, to address dye pollution in textile wastewater, waste cotton-based yarn was utilized as both a cheap and sustainable adsorbent and a precursor for carbon adsorbent production. Cotton and cotton/polyester yarn samples underwent thermal modification through carbonization followed by chemical activation with KOH. Various techniques including nitrogen adsorption-desorption isotherms, scanning electron microscopy, Fourier transform infrared spectroscopy, and surface charge determination were employed to analyze the morphological and surface properties of the cotton-based adsorbents. Adsorption properties were evaluated by testing the removal of selected cationic and anionic dyes from water. The impact of temperature, contact time, initial concentration, and pH of the adsorbate solution on adsorption was investigated, with experimental data analyzed using theoretical models. While carbonization alone did not significantly enhance adsorption properties, activated samples exhibited high efficacy in removing both cationic and anionic dyes from water. Despite the negative influence of the polyester component in the carbon precursor on the efficiency of activated samples in removing methyl orange, results indicated that activated cotton and cotton/polyester yarn could be used to prepare highly efficient adsorbents for the rapid removal of methylene blue from real wastewater samples.

Households and businesses are generating unprecedented levels of electrical and electronic wastes (e-waste), fueled by modernisation and rapid obsolescence. While the challenges imposed by e-waste are similar everywhere in the world, disparities in progress to deal with it exists; with developing nations such as South Africa lagging. The increase in e-waste generation increases the need to formulate strategies to manage it. This paper presents an overview of e-waste management on a global and South African scenarios with a specific case for Cathode Ray Tube (CRT) waste management practices in South Africa. CRTs present the biggest problem for recyclers and policy makers because they contain hazardous elements such as lead and antimony. Common disposal practices have been either landfilling or incineration. The research into the South African practices with regards to CRT waste management showed that there is still more to be done to effectively manage this waste stream. This is despite clear waste regulatory frameworks in the country. However, recent developments have placed e-waste as a priority waste stream, which should lead to intensified efforts in dealing with it. Overall, these efforts should aim to maximise diversion from landfilling and to create value-addition opportunities, leading to social and environmental benefits.

Solvent free copolymerization of epoxides derived from fatty acid esters of waste cooking oil with phthalic anhydride using (salen)CrIII Cl as catalyst and n-Bu4NCl/DMAP as co-catalyst was carried out for the first time under microwave irradiation, where reaction time was reduced from number of hours to minutes. The polyesters were obtained with molecular weight (Mw = 3084-6740 g/mol) and dispersity values (D = 1.18-1.92), when (salen)CrIII Cl/n-Bu4NCl was used as catalysts. While in case of DMAP as a co-catalyst, polyesters with improved molecular weight (Mw = 5537-6925 g/mol) and narrow dispersity values (D = 1.07-1.28) were obtained even at reduced concentrations of (salen)CrIII Cl and DMAP. The obtained products were characterized and evaluated by attenuated total reflection-fourier transform infrared spectroscopy (ATR-FTIR), proton nuclear magnetic resonance (1H-NMR) spectroscopy, gel permeation chromatography (GPC) and thermogravimetric analysis (TGA) Techniques.

Waste glycerol can be subjected to various processing operations, including purification and re-fining, to obtain glycerol of appropriate purity. In addition, alternative methods of utilising waste glycerol are also being sought, e.g. by converting it into other valuable chemical products or biofuels. Therefore, various technologies are being developed to utilise this type of waste effectively and sustainably. The production of value-added products from waste glycerol is an important issue that determines the improvement of the economic viability of biofuel production and corresponds to the model of a waste-free and emission-free circular economy. This paper characterised the mechanisms and evaluated the efficiency of existing methods of microbiological utilisation of waste glycerol into liquid biofuels, including biodiesel, bioethanol and biobutanol, and identified further directions for the production of value-added products. In addition, a bibliographical analysis of publications re-lated to the production of liquid fuels and economically valuable products from glycerol was carried out, the progress of research and application work was assessed and directions for future research were identified.

Experimental studies on the development of processes of obtaining ultradispersed metal-ceramic materials and coatings Mo-ZrO₂, Mo-Al₂O₃, W-ZrO₂, W-Al₂O₃ CVD by deposition from the gas phase in CO₂ process using low-temperature nonequilibrium plasma were carried out.The structure, microhardness, phase composition, and high-temperature annealing behavior of the materials were studied. It is shown that the choice of parameters of the deposition process and temperature annealing can be controlled by the distribution function of ultradispersed particles in the material and their sizes.High-temperature X-ray studies of "molecular" two-phase alloys Mo- Al₂O₃ and Mo- ZrO₂show that, depending on the elastic and thermal properties of the matrix materials and dispersed particles, the molybdenum matrix can be in an all-round tensed or all-round compressed state.In the study of the electro-physical characteristics of the two-phase disperse-strengthened alloys Mo- ZrO₂, Mo- Al₂O₃, W- ZrO₂, W- Al₂O₃ it has been established that in the region of temperatures 1023...1273K anomalous changes of specific electrical resistance and instability of thermal eddy in magnitude are observed apparently connected with the presence of internal stresses in material caused by ultradisperse particles.Theoretical aspects of the problem of increasing the carriers density in nanocomposite materials are reviewedTheoretical analysis of the effect of the ensemble of microparticles on the change of electron density in ultradisperse metal-ceramic materials is carried out. It is shown that the average values of the electron density in the matrix with the introduction of 1% of particles with a radius of 50 A increase by more than two orders of magnitude.The possibilities of creating ultradisperse compositions using radiation-plasma methods are considered.

The development of efficient luminescent systems, such as microcavities, solid state lasers, integrated optical amplifiers, optical sensors is the main topic in glass photonics. The building blocks of these systems are glass-ceramics activated by rare earth ions because they exhibit specific morphologic, structural and spectroscopic properties. Among various materials that could be used as nanocrystals to be imbedded in silica matrix, tin dioxide presents some interesting peculiarities, e.g. the presence of tin dioxide nanocrystals allows increase in both solubility and emission of rare earth ions. Here, we focus our attention on Er³⁺ - doped silica – tin dioxide photonic glass-ceramics fabricated by sol-gel route. Although the SiO₂-SnO₂:Er³⁺ could be fabricated in different geometrical systems: thin films, monoliths and planar waveguides we herein limit ourselves to the monoliths. The effective role of tin dioxide as luminescence sensitizer for Er³⁺ ions is confirmed by spectroscopic measurements and detailed fabrication protocols are discussed.

Recycling information can be complex and often confusing which may subsequently reduce the participations in any waste recycling schemes. As a result, this research explored the roles as well as the importance of a holistic approach in designing recycling information using 15 expert-based in-depth interviews. The rationale was to offer a better understanding of what constitutes waste, recycling, and how recycling information should be designed and presented to make recycling more attractive/convenient. Based on the research participants’ perceptions with supports from the existing studies, this research sub-categorised recycling information into three different themes, termed the “WWW” of recycling information components. As a result, these components (or attributes) were extensively described (using findings of semi-structured interviews) to elicit pragmatic guidance for practitioners, policy-makers, and other stakeholders in designing structured communication or information strategies that may simplify and subsequently increase waste-recycling practices. The policy implications of holistic information in enhancing recycling are further discussed.

The global increase in population has placed significant pressure on food security, leading to the emergence of aquaculture as a vital source of aquatic foods. However, rising costs and the limited availability of fishmeal in aquafeeds have spurred the search for alternative protein sources. While plant-based ingredients have been integrated into commercial aquafeeds, they come with challenges, including low protein content, palatability issues, and the presence of antinutritional factors. In this context, fish silage, derived from fish waste and discarded fish, stands out as a promising alternative technology due to its cost-effectiveness and sustainability attributes. The production of fish silage involves the addition of organic/inorganic acids or lactic acid bacteria to homogenized fish waste. This process yields a valuable mixture rich in peptides, free amino acids, and partially hydrolyzed proteins, offering significant nutritional benefits for animal diets. Beyond its nutritional advantages, fish silage contributes to environmental sustainability by reducing the impact of waste disposal and enhancing the value of fish waste. The objective of this review is to promote sustainable practices in the aquaculture industry in response to the increasing demand for high-quality feed nutrients. To achieve this, it includes an analysis of research results related to silage technology, an appraisal of the advantages and disadvantages of using fish silage as a feed additive, and a focus on emerging trends in this field.

In our study we investigated the additive manufacturing (AM) of ceramic-based Functionally Graded Materials (FGM) by the direct AM technology Thermoplastic 3D-Printing (T3DP). Zirconia components with a varying microstructure were additively manufactured by using thermoplastic suspensions with different contents of pore forming agents (PFA) and were co-sintered defect-free. Different materials were investigated concerning their suitability as PFA for the T3DP process. Different zirconia-based suspensions were prepared and used for AM of single- and multi-material test components. All samples were sintered defect-free and in the end we could realize a brick wall-like component consisting of dense (<1% porosity) and porous (approx. 5% porosity) zirconia areas to combine different properties in one component. The T3DP opens the door to AM of further ceramic-based 4D-components like multi-color or multi-material, especially multi-functional components.

The valorization of the large amount of crude glycerol formed from biodiesel industry, is of primordial necessity. One possible direction with high interest to the biorefiniery sector is the production of fuel additives as solketal, though the acetalization of glycerol with acetone. This is a chemical process that conciliates high sustainability and economic interest, since solketal contributes to the fullfilment of a Circular Economy Model through its use in biodiesel blends. The key to guarantee high efficiency and high sustainability for solketal production is the use of a recovery and recyclable heterogeneous catalyst. Some examples are already reported in the literature (first example in 2012), and this review intends to conciliate the information spreaded in this topic and established the most important reacional parameters and the main catalytic characteristics strategies to achieve high solketal production in short reaction time.

Solid waste management in Accra is a major challenge to the Metropolitan Authorities and inhabitants. The rapidly increasing population coupled with poor capacity of the municipal and private waste management companies to management waste effectively has created issues of environmental concern. Due to poor waste managements systems, most household dispose waste indiscriminately leading to floods and health issues. The study showed that about 60% of household waste is organic materials which has the potential to be converted to compost for agriculture purpose. Meanwhile plastics and rubbers which litters the environment as well as blocking major storm drains and gutters hence creating huge environmental hazard is made of 11% of the total component of most household waste generated daily. The study also revealed that among the methods of disposing waste, dumping waste in skip containers located at authorized places was the preferred means of disposing waste by household though others also dispose waste by other means such as burying and burning. Inadequate skip containers per population of household in an area coupled with irregularity of tracks picking these containers makes skip containers dumping site ugly scene, hence creating health issues. Among the constraints that impact negatively on sustainable waste management in Accra Metropolis, economic constraints was perceived as the main challenge which affect efficient waste management. Currently the country is going through serious economic challenges so government does not release money timely to fund projects which waste management is key. Most donor partners that use to support the government with funds have either reduced or redrawn their services as they have no confidence in the state of Ghana economy. Aside the constrains, the study also indicated that factors such as poor public attitude towards waste management, poor enforcement of sanitation by-laws, inadequate and untimely release of government funds were also seen as the main factors affecting waste management.

Sr4Al6O12SO4 samples were obtained from the compound mixture formed by a solid–state reaction of Al2O3, SrSO4, and SrCO3. Samples were compacted at 100MPa to form pellets of 1 and 4cm in diameter and were sintered at 1400°C for 4 hours. The compound was analyzed by X–ray diffraction. Static immersion and wettability tests were performed to evaluate corrosion resistance in contact with Al–Si. Corrosion tests were carried out by immersion at 800, 900, and 1000°C for 24, 50, and 100 hours, while wettability was carried out at 900, 1000, and 1100°C for 2 hours. Subsequently, the samples were prepared metallographically. Samples were analyzed by optical microscopy, scanning electron microscopy, and image analysis. In general, reaction products consisting of alumina, spinel, oxides, and sulfates were found. The contact angles obtained were 124° to 135°. It is concluded that ceramic substrate Sr4Al6O12SO4 is resistant to corrosion by Al–Si alloy, since the slight thickness of the reaction products found in the samples (100μm) considering the severe conditions of the experiment: 1000°C and 100 hours of isothermal temperature. Furthermore, it can be said that Sr4Al6O12SO4 is not wettable by Al–Si alloys.

membrane separation technology shows promise, particularly gas separation membranes, including ceramic membrane. Ceramic membranes are increasingly gaining attention for their acid and alkali stability, corrosion resistance, high-temperature tolerance, and mechanical strength. This study focuses on alumina support ceramic membrane for CO2 capture. The membranes were characterized using contact angle measurements, scanning electron microscopy (SEM), and Fourier Transform Infrared spectroscopy (FTIR) analysis. The contact angle measurements confirmed the hydrophilic, while SEM analysis showed even particle distribution in the alumina ceramic membranes respectively. EDAX analysis revealed the elemental composition in the alumina support matrix. FTIR analysis demonstrated chemical interactions of the support membrane. Single gas permeation experiments were conducted. It can be observed that Nitrogen gas permeated faster with increase in feed pressure through the unmodified ceramic inorganic hydrophobic membrane more than the other two single gases, O2, and CO2). As a result, only high permeance separation membranes with realistic size and pressure conditions may be considered of as a practical alternative for CO2 capture. However, the presence of non-selective defects limited the improvement in selectivity of hydrophilic ceramic membrane. In this case, there is need to modify the ceramic membrane used to increase the flux, permeance of CO2, and selectivity of CO2.

Abstract: membrane separation technology shows promise, particularly gas separation membranes, including ceramic membrane. Ceramic membranes are increasingly gaining attention for their acid and alkali stability, corrosion resistance, high-temperature tolerance, and mechanical strength. This study focuses on alumina support ceramic membrane for CO2 capture. The membranes were characterized using contact angle measurements, scanning electron microscopy (SEM), and Fourier Transform Infrared spectroscopy (FTIR) analysis. The contact angle measurements confirmed the hydrophilic, while SEM analysis showed even particle distribution in the alumina ceramic membranes respectively. EDAX analysis revealed the elemental composition in the alumina support matrix. FTIR analysis demonstrated chemical interactions of the support membrane. Single gas permeation experiments were conducted. It can be observed that Nitrogen gas permeated faster with increase in feed pressure through the unmodified ceramic inorganic membrane more than the other two single gases, O2, and CO2). As a result, only high permeance separation membranes with realistic size and pressure conditions may be considered of as a practical alternative for CO2 capture. However, the presence of non-selective defects limited the improvement in selectivity of hydrophilic ceramic membrane. In this case, there is need to modify the ceramic membrane used to increase the flux, permeance of CO2, and selectivity of CO2.

Nickel-based superalloys are attractive to many industrial sectors (automotive, military, energy, aerospace etc.). However, their physical properties make them difficult to machining using traditional tools. Therefore, the new materials for the machining of Ni-based alloys are required. Ceramic-based composites could act as a tool to replace the current materials. The incentives for this paper are to provide an overview of existing ceramic composites and draw some conclusions that will help in solving the problem of choosing materials for processing of Ni-based superalloys. Despite the diversity of ceramic composites in this work the focus was on the SiAlON ceramic.

To determine the fracture rate of ceramic crowns and causes of ceramic crown failure, this study used keywords—namely “endocrown,” “veneered fixed dental prosthesis,” “monolithic lithium disilicate (LS2),” and “all-ceramic single crown”—to search for articles published in English from 2005 to 2023 in the PubMed electronic database. Rather than using the Boolean logic algorithm between MESH terms and keywords, we accurately calculated the numbers of final clinically tracked cases with crown fractures from the contents of articles. The titles and abstracts of many related articles focused on implant or abutment fracture, while crown fracture was investigated and mentioned only in the main texts of the articles. Our studies included those crowns as well as having more complete data collection. Our search yielded 228, 93, 404, and 358 articles for the keywords “endocrown,” “veneered fixed dental prosthesis,” “monolithic lithium disilicate (LS2),” and “all-ceramic single crown,” respectively. We used the Newcastle–Ottawa Scale (NOS) to assess article quality, and our inclusion criteria were randomized controlled trials (RCT) and cohort study articles involving more than 3 years of follow-up and more than 20 cases. After reviewing, 16 high-quality articles were selected for analysis. The 4.4% crown fracture rate recommended on the basis of most clinical results was achieved in only 6 of the 16 articles. In these 6 articles, the researchers concluded the following reasons that may cause the crown fractures: the thickness of the veneer ceramic material; the connector dimensions; pontic span of the fixed prosthesis; the type of cement; the treatment of the ceramic surface before luting. Other articles inferred that the computer-aided design libraries that were insufficient for the creation of appropriate anatomically supported frameworks for prostheses with ceramic veneers; the thermal expansion coefficient and fracture toughness of the framework material did not match those of the veneer ceramic, resulting in an insufficient area supporting the ceramic veneer then leads to premature crown failure after a long period chewing. The future prospective for material developing could focus on solving those problems and have better clinical results.

This report aimed to know the performance of local mineral-based composite ceramic. The materials used consist of Indonesian local minerals, which are jarosite and manganite minerals as sources of oxide iron and Mangan. The materials were synthesized using the precipitation method, whereas composite ceramic was fabricated using a screen printing method and fired at 600 oC using a furnace. The results of the characterizations indicate that the sample forms three phases on diffraction peaks. The differences in the resistance values in ambient and ethanol environments indicate that the sample has very different responses. The high porosity of the sample greatly support the gas adsorption process. Thus, the sample has a high level of sensitivity. With the above characteristics, the composite ceramic which was fabricated has the potential to be applied to gas sensors, especially ethanol gas sensors.

Low temperature cofired ceramics (LTCC) have conquered a niche segment in biological microelectromechanical systems (BioMEMS) during the last two decades. Since 3-dimensional assembly and rapid prototyping capability are outstanding features of the technology, bioreactors with complex geometry can easily be produced. Particularly needed functions are working electrodes, e.g. for impedance measurements and reference electrodes consisting in platinum or silver-silver chloride. Although the distinct grainy surface of thick film materials influences the double layer properties, data describing the bioelectronic interface and biocompatibility of common thick film materials are rarely published up to now. This works aims to fill this gap by studying the surface properties, composition, electrochemical properties and biocompatibility of commercially available thick film materials. It was found that thick film gold is suitable as electrode material in direct cell contact since an appropriate proliferation of the cell culture was observed. Poly(3,4-ethylenedioxythiophene) coating decreases the absolute value of the zeta potential of thick film gold from 16.55 V to 11.78 mV without any change in vitality of the cells. Thick film platinum layers have a porous structure entailing an enlargement of the effective surface by a factor of 21.6 and can be used as reference instead of silver/silver chloride, which was identified to be incompatible with cell culture. The investigations show that some commercially available cost-effective thick film materials are compatible with cell culture and the here presented data give an orientation for the use of the same in LTCC bioreactors.

This paper presents the results of investigations into the pyrolysis of waste polypropylene in a laboratory fixed-bed batch reactor. The experiments were designed and verified in such a way as to allow the application of the Response Surface Methodology (RSM) in the development of an empirical mathematical model that quantifies the impacts mentioned above. The influence of the mass of the raw material (50, 100 and 150 g), together with the reactor temperature (450, 475 and 500 °C) and the reaction time (45, 50 and 75 min) was examined. It has been shown that the mass of the raw material, i.e. the filling volume of the reactor, has a significant influence on the pyrolysis oil yield. This influence exceeds the influence of reactor temperature and reaction time. This was explained by observing the temperature change inside the reactor at three different spots at the bottom, middle and top of the reactor. Recorded temperature diagrams show that with greater masses of feedstock, local overheating occurs in the middle part of the reactor, which leads to overcracking of vapor products, and from there to an increased formation of non-condensable gases, i.e. reduced yield of pyrolytic oil.

Colombia is the world's leading producer of mild washed arabica coffee and produces 12.6 million bags of green coffee, but at the same time 784,000 tons of waste biomass are dumped in open fields, of which only 5% is recovered or used. The objective of this project was to evaluate the production of platform chemicals from these coffee wastes. To achieve this, biomass characterization was carried out using proximate analysis, ultimate analysis and structural analysis. Hydrothermal valorization was carried out at a temperature range of 120-180 °C (LHW) and 180-260 °C (HTC) for one hour, the platform chemicals obtained were quantified by HPLC-IR, monitored by pH and conductivity, and the solid fraction was characterized by monitoring the functional groups in IR spectroscopy, and elemental analysis. Hydrolysis processes were obtained from 150 °C, production of platform chemicals from 180 °C and maximum concentration at 180 °C-4h, over 200 °C degradation of the products in the liquid fraction starts to take place. Homogeneous basic and acid catalysts were used to improve the yields of the reaction. The kinetics of the hydrolysis of lignocellulosic structures to sugars were also analyzed and described, and reaction orders of 1 (LHW), 3 (HTC) and their respective reaction rate equations were reported.

There is a need to find methods to intensify the anaerobic digestion process. One possibility is the use of pre-treatment techniques. Many laboratory tests confirm their effectiveness, but in most cases, there is no verification work carried out on industrial plants. The aim of the research carried out under laboratory conditions and on a large scale was to determine the technological and energy efficiency of the use of hydrodynamic cavitation in the pre-treatment of a waste mixture from dairy farms. It has been shown that hydrodynamic cavitation significantly increases the concentration of organic compounds in the dissolved phase. In the most effective variants, the increase in the content of these indicators was over 90% for both COD and TOC. The degree of solubilisation achieved was 49±2.6% for COD and almost 52±4.4% for TOC. Under laboratory conditions, the highest effects of anaerobic digestion were achieved after 10 minutes of pre-treatment. The amount of biogas was on average 367±18 mL/gCOD and the amount of methane 233±13 mL/gCOD. Further large-scale optimisation trials showed that after 8 minutes of hydrodynamic cavitation, the biogas yield was 327±8 L/kgCOD with a CH4 content of 62.9±1.9%. With this variant, the net energy yield was 66.4±2.6 kWh/day, a value that was 13.9% higher than the original variant with 10 minutes of disintegration and 3.1% higher than the variant without pre-treatment.

This paper examines the relationship between GDP per capita and waste generated in European Union countries, highlighting the importance of this relationship for understanding the environmental consequences of economic growth and formulating waste management policies. The analysis findings demonstrate that, in most cases, higher GDP is associated with higher amounts of waste, although there are exceptions to this trend. A smaller number of countries are also found where no such relationship exists. These are primarily high-income countries in the lower part of the EKC or countries in transition. Cluster analysis reveals regional differences in the relationship between GDP and waste that the economic factors and the level of development in the regions concerned can explain. Bulgaria is among the European countries with the lowest economic growth associated with a large amount of waste. The analysis, therefore, focuses on Bulgaria. The impact of GDP per capita, Human Development Index and Population Density on municipal waste in Bulgaria is studied. The aim is to identify significant relationships and dependencies between these factors and the amount of waste. Based on the results of multiple regression analysis and the findings from municipal waste management data in Bulgaria, specific actions are proposed for municipal waste management in the country. Recommendations are made for developing sustainable waste management policies and sharing best practices between regions.

Multi-wire saw machining (MWSM) used for slicing hard-brittle materials in semiconductor, is an important material removal process that uses free abrasives. Cutting model of single-wire saw machining (SWSM) is the basis of MWSM, and the material removal mechanism of SWSM can better understand than MWSM. Mathematical model (includes brittle fracture and plastic deformation) is presented in this paper for SWSM ceramic with abrasives. This paper determines the effect of various machining parameters on the removal of hard-brittle materials. For brittle fracture of SWSM ceramics, the minimum of the strain energy density is used as a fracture criterion. The material removed of SWSM ceramics due to plastic deformation is calculated using the equations of motion. Actual wire-sawing experiments are conducted to verify the results from the developed mathematical model. Theoretical results agree with experimental data and practical experience. The developed mathematical model shows that brittle fracture plays a major concern role in material removed of SWSM ceramics. Wire speed and working load have positively correlated with material removed of SWSM ceramics. The coefficient of friction is low, a lateral crack, which propagates almost parallel to the working surface, leads to more brittle fracture and material removed is increased on SWSM ceramics.

Magnetic ceramic nanoparticles system xTm2O3-(1-x)alpha-Fe2O3 (x=0.1 and 0.5) was synthesized by mechanochemical activation starting from hematite and thulium oxide precursors and characterized by transmission Mӧssbauer spectroscopy. The Mӧssbauer spectra were typically analyzed considering 1-3 sextets, corresponding to hematite (with and without thulium doping) and a doublet, representing thulium iron perovskite (thulium orthoferrite). The magnetic hyperfine fields (BHF) and doublet abundance were studied as function of the ball milling time (BMT) for both molar concentrations employed. The results are consistent with the formation of solid solutions in the investigated system. The mixed-oxide nanoparticle system synthesized may have important applications in displays, sensors and photovoltaics, and is paving the way for emerging utilizations related to mechanically flexible electronics.

The increase in global warming due to NOx, CO2, and CH4 harmfully different ecosystems and significantly prejudice world life. A promising methodology in this sense is the pollutant conversion into valuable chemicals from photocatalytic processes by reusable photocatalyst. In this way, the present work aimed to produce a Nb2O5 photocatalyst nanofibers system to convert CO2 by the electrospinning method. Based on the collected data, the nanofibers calcination at 600°C for 2 h resulted in the best condition to obtain a homogeneous surface with an average diameter of 84 nm. As a result, the Nb2O5 nanofibers converted CO2 mostly into CO and CH4, reaching values around 8.5 μmol g−1 and 0.55 μmol g−1, respectively.

In municipal waterworks large amounts of waste in the form of sludge have to be discarded. This investigation focuses on the processing of ceramic floor tiles incorporated with a municipal waterworks sludge. Four floor tile formulations containing up to 10 wt. % of the municipal waterworks sludge in replacement of kaolin were prepared. The floor tile processing route consisted of dry powder granulation, uniaxial pressing, and firing between 1190 and 1250 °C using a fast-firing cycle (<60 min). The densification behavior and technological properties of the floor tile pieces as function of the sludge addition and firing temperature were determined. The development of the microstructure was followed by XRD and SEM/EDS. The results show that the replacement of kaolin with municipal waterworks sludge, in the range up to 10 wt. %, allows the production of ceramic floor tiles (group BIb and group BIIa, ISO 13006 Standard) at lower firing temperatures. These results suggest a new possibility for valorization of municipal waterworks sludge with many economical and environmental benefits.

Ghana Tamale's current waste management system is overwhelmed by the growing waste crisis, necessitating the exploration of Waste-to-Energy technologies as an innovative solution. This study explores challenges and opportunities for integrating Waste-to-Energy (WtE) technologies into Tamale's existing waste management system. Qualitative research identified policy hurdles, financial constraints, social concerns, and institutional weaknesses as key barriers. Conversely, stakeholder collaboration, public education, and capacity building emerged as some success fac-tors. A proposed implementation plan emphasizes feasibility studies, public engagement, pub-lic-private partnerships (PPPs), and technology selection based on waste composition. Addition-ally, a novel framework for WtE integration within a broader Integrated Solid Waste Manage-ment (ISWM) system is presented. This framework incorporates waste sorting, recycling, WtE alternatives, and responsible management of residuals. Validation by key stakeholders con-firmed the framework's potential to improve waste management in Tamale. By overcoming identified challenges and implementing the proposed framework, Tamale can achieve environ-mental sustainability, energy generation, and progress towards UN SDGs 7, 11, and 12. This re-search offers valuable insights for policymakers and paves the way for a cleaner and more sus-tainable future for Tamale, potentially serving as a model for other developing cities.

Inadequately managed agricultural waste significantly impacts the environment, health, and economy. This form of pollution arises from the underutilization, poor awareness, and insufficient treatment of agricultural waste. Fruit and vegetable wastes are valuable sources of bioactive compounds. This study aims to revalorize discarded waste from red habanero chili peppers (Capsicum chinense) by extracting bioactive compounds through different extraction processes: maceration (ME), maceration assisted by ultrasound (US), Soxhlet extraction (SE), supercritical fluid extraction (SFE), and supercritical fluid extraction with a co-solvent (SFEC). Extraction processes have significant effects on extraction efficiency and phytochemical profile (capsaicinoids and carotenoids recovery). The results indicate that the highest efficiency process is obtained with SFEC, also a high phytochemicals recovery (14.9 mg of total capsaicinoids and total carotenoids 292.09 µg per gram of sample). Concerning to phytochemical profile in the extract, the maceration process gets the highest concentration of compound followed by US and SFEC. These data reveal that the use of SFE and SFEC extraction is recommended for extraction of phytochemicals with biologically activity from red habanero chili pepper waste for diverse industries application.

This study aims to explain individual engagement in sustainable waste management behaviors (SWMBs) based on the application of protection motivation theory (PMT). SWMBs include waste avoidance, green purchasing behavior, reuse and recycle, and waste disposal behaviors. This study applies PMT to explore how individuals’ SWMBs are influenced by their perceived threats caused by environmental contamination from waste disposal and their perceived coping capability. The Bangkok metropolitan area was selected as a case study because it has faced serious waste management problems caused by massively increasing amounts of solid waste during the last ten years. Questionnaire surveys were conducted with 193 public and private officers residing in the city of Bangkok. The one-way analysis of variance (ANOVA) was performed to justify the effect of individual threat appraisal and coping appraisal on the engagement in SWMBs. The results demonstrated that respondents’ self-efficacy highly influenced all types of SWMBs. The perceived probability of being impacted from pollutants influenced all of the SWMBs except green purchasing behaviors. Response efficacy did not influence all SWMBs; however, the perceived severity of adverse consequences caused by pollutants highly influenced reuse and recycle behaviors. It could be suggested that PMT is well suited for investigating low-cost and simple SWMBs. It could also be suggested that different communication campaigns should be established to enhance citizens’ engagement in each type of SWMB.

Two secondary waste materials, municipal incinerator bottom ash (MIBA) and sewage sludge ash (SSA), were mixed with clay for ceramic manufacturing in this study. Specimens with 5 different MIBA replacement amount of 0%, 5%,10%, 15%, and 20%(wt) and 3 different SSA replacement amount of 0%, 10%, and 20%(wt) were prepared and then a series of tests and analysis were conducted to investigate how the two materials affect the quality of the final product and to what extent. It concludes that a mix with up to 20% of SSA and 5% of MIBA could result in quality tiles complying with specifications for interior or exterior flooring applications at certain kiln temperatures.

Singapore, being a land-scarce country, is heavily dependent on imported food, which poses a challenge in ensuring food security. In addition, the substantial amount of food waste generated in Singapore further deepens food insecurity challenges, imposing enormous pressure on the country's food and land resources. In the recent years, valorising food waste streams into higher value products has been an increasing trend in tackling food wastage due to its economical and environmental benefits. This paper provides a thorough review on food waste valorisation in Singapore and summarizes critical information from the current food landscape to the food waste management strategies adopted. The review highlights the prototypes developed from food waste streams by the local research and development capabilities and the technological processing and techniques used for versatile applications ranging from food and nutraceuticals to urban agriculture. The challenges associated with the valorisation of food waste are also addressed. Two ambitious Initiatives by the Singapore government Zero Waste Plan and the 30-by-30 food security goal to encourage food waste valorisation are explored and presented. The review serves as a reference for other countries in ensuring food security and achieving sustainable development goals.

Waste-to-Hydrogen (Wahh) is a process of converting waste into hydrogen gas through various methods such as thermal conversion, biological conversion, and chemical conversion. This process not only helps in managing waste but also provides a clean source of energy as hydrogen is a renewable energy source that produces zero greenhouse gas emissions during combustion. Wahh has the potential to provide a sustainable solution for energy generation and waste management in the current scenario of globally increasing energy demands. This study aims to examine the properties and energy efficiencies of various renewable fuels including fuelwood, biogas, biomethane, and biohydrogen with a specific focus on differentiating the characteristics of biohydrogen. The paper explores the emerging concepts of waste-to-hydrogen microgrids, biohydrogen refineries, biohydrogen prosumer networks, and a biohydrogen circular economy, as well as Public-Private-People Partnerships (4Ps) and the hydrogen-centric renewable energy revolution, which are taking shape in industrialized countries. The study presents a comprehensive feasibility analysis of these concepts in the context of Nepal. The results of this research will provide valuable insights into the potential for adopting these innovative technologies in Nepal and will contribute to the development of a sustainable and efficient energy system.

Objective: To determine the effect of sandblasting before and after sintering on the surface roughness of zirconia and the micro-tensile bond strength of a pressable veneering ceramic to zirconia. Methods: Pre-sintered zirconia blocks (IPS e.max ZirCAD, Ivoclar Vivadent) were divided into a control group (CTR, no surface treatment) and four test groups of three specimens each: Pre-S-30, Pre-S-50, Pre-S-110 were sandblasted with 30µm SiO2, 50µm Al2O3 and 110µm Al2O3 particles respectively, before sintering, Post-S-30 was sandblasted with 30µm SiO2 after sintering. For each treatment, the surface roughness was measured (Ra, Perthometer M4P, Mahr Perthen). After sintering the zirconia blocks, a liner and a pressable ceramic (IPS e.max ZirPress, Ivoclar Vivadent) were fired. Sixteen micro-bars were obtained from each block and submitted to the micro-tensile bond strength (µTBS) test. Data were analyzed with one-way ANOVA. Any correlation between Ra and µTBS was evaluated (Sperman test). Results: Sandblasting before sintering with 110µm Al2O3 (Ra=3.44±0.44µm), 50µm Al2O3 (Ra=2.32±0.46µm), and 30µm SiO2 (Ra=1.22±0.22µm) resulted in significantly higher roughness than sandblasting after sintering with 30µm SiO2 (Ra=0.46±0.11µm). The highest µTBS was measured when the sintered zirconia was sandblasted with 30μm SiO2 (26.79±14.80 MPa), which was significantly different from that of specimens that were sandblasted before sintering (Pre-S-30=20.90±11.70; Pre-S-50=21.27±15.19; Pre-S-110=23.99±16.83) or were not treated (CTR=17.44±14.03). Conclusions: Sandblasting zirconia before sintering enhances the surface roughness proportionally to the particle size of the sand used. Sandblasting with 30µm SiO2 after sintering appeared to improve bonding between the veneering ceramic and zirconia. Clinical Significance: Sandblasting with 30µm SiO2 after sintering may improve bonding between veneering ceramics and zirconia, thus reducing ceramic fractures/chippings.

This topical review describes the results of recent research into and development of silicon nitride, a ceramic material with unique properties. The outcome of this ongoing research strongly encourages the use of monolithic silicon nitride and coatings as contemporary and future biomaterial for a variety of medical applications. Crystallographic structure, synthesis and processing of monolithic structures and coatings, and examples of their medical applications are covered that relate to spinal, orthopedic and dental implants, bone grafts and scaffolds, platforms for intelligent synthetic neural circuits, antibacterial and antiviral particles and coatings, optical biosensors, and nano-photonic waveguides for sophisticated medical diagnostic devices. The examples provided show convincingly that silicon nitride is destined to become a leader to replace titanium and other entrenched biomaterials in many fields of medicine.

Fired bricks have shown tremendous potential as a construction material due to their properties. However, their use required some specifications in terms of quality, resistance, and durability. In developing countries, the lack of tools to make test specimens leads to many defects in these brick specimens responsible for low durability and weak precision during mechanical tests and shrinkage. In this study, a simple and traditional method of making test bricks is presented. This simple method allows the production of bricks with the required properties. This method is especially efficient for a firm or semi-soft pastes consistency. The handmade pastes do not stick into the walls of the mold like the case of steel molds and it gives specimens with standard shape, smooth surface, and sharp edges. The resulting fired bricks exhibit high mechanical strength comparable and even better than those of conventional methods.

Currently, there is a tenacious need to find new ways to purify water by eliminating bacterial biofilms, textile dyes, and toxic water pollutants. These contaminants pose significant risks to both human health and the environment. To address this issue, in this study, we have developed an eco-friendly approach that involves synthesizing Cobalt-doped Cerium Iron Oxide (CCIO) nanocomposite (NC) using an aqueous extract of Gossypium arboreum L. stalks. The resulting nanoparticles can be used to effectively purify water and tackle the challenges associated with these harmful pollutants. Nanoparticles excel in water pollutant removal by providing high surface area for efficient adsorption, versatile design for simultaneous removal of multiple contaminants, catalytic properties for organic pollutant degradation, and magnetic features for easy separation, offering cost-effective and sustainable water treatment solutions. CCIO nanocomposite has been synthesized by green co-precipitation method due to biomolecules and co-enzymes present in the aqueous extract of Gossypium arboreum L. stalk; a single-step procedure completed in 5 h reaction time. Further, the synthesis of nanocomposites was confirmed by various characterization techniques such as Fourier-transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), Field emission scanning electron microscopy (FE-SEM), Transmission electron microscopy (TEM), Thermogravimetric analysis (TGA), Dynamic light scattering (DLS), and Energy Dispersive X-Ray (EDX). CCIO NCs were discovered to have a spherical shape and an average size of 40 nm. Based on DLS zeta potential analysis, CCIO NCs were found to be anionic. Also, CCIO NCs showed significant antimicrobial and antioxidant activity. Overall, considering the physical and chemical properties, the application of CCIO NCs in the adsorption of various dyes (~91 %) and water pollutants (chromium = ~ 60 %) has been considered since they exhibit great adsorption capacity owing to their microporous structure which can be a step forward in water purification.

Within the past few decades, thousands of experiments have been performed to characterize waste and biomass to estimate the bioenergy potential and product identification. There is a need to develop an integrated process model based on experimental literature, and simulation to obtain suitable products. In this study municipal solid waste (MSW) characterization and integrated process model have been developed to optimize final products in a reactor system. The process model has two modes R&amp;D and reactor control (RC) to obtain suitable products including bio-oil, char, and gases. A database was integrated based on thermokinetics, machine learning and simulation models to optimize product efficiency. The experimental data includes thermogravimetric analysis, Fourier transform Infrared Spectroscopy, Gas chromatography, and Mass spectrometry, which are linked with pyrolysis experimental setup. Feedstock-product mapping models were incorporated into the database along with the temperature, heating rates, elemental analysis, and final product concentration, which are utilized for pyrolysis reactor setup. Product feasibility is conducted based on lifecycle cost, affordability, and product efficiency. The present work will bridge the gap between experimental study and decision making based on obtained products at several experimental conditions around the world.

Background: Lithium di-silicate dental ceramics bonding, realized by using different resins, is strictly dependent on micro-mechanical retention and chemical adhesion. The aim of this in vitro study was to investigate the capability of a 1070 nm fiber laser for their surface treatment. Methods: Samples were irradiated by a pulsed fiber laser at 1070 nm with different parameters (Peak Power from 5 kW to 5 kW, RR 20 kHz, speed from 10 to 50 mm/s, total Energy Density from 1.3 to 27 kW/cm²) and the thermal elevation during the experiment was recorded by a Fiber Bragg Grating (FBG) temperature sensor. Subsequently, the surface modifications were analysed by optical microscope, Scanning Electron Microscope (SEM) and Energy Dispersive X-ray Spectroscopy (EDS). Results: With a Peak Power of 5 kW, RR of 20 kHz and speed of 50 mm/s, the microscopic observation of the irradiated surface showed increased roughness with small areas of melting and carbonization. EDS analysis revealed that, with these parameters, there are no evident differences between laser-processed samples and controls. Thermal elevation during laser irradiation ranged between 5 °C and 9 °C. Conclusions: 1070 nm fiber laser can be considered as a good device to increase the adhesion of Lithium di-silicate ceramics.

Water pollution is the main problem in the current scenario which is being faced by mankind due to the industrial and commercial effects. Industrial effluents contain heavy metals and inorganic ions like nitrates and phosphate ions. These ions are being included in waterways through industrial runoff. When the concentration of these hazardous pollutants increases in aquatic flora and fauna causes severe health problems. So remediation of these toxicants from water reserves is of chief importance. Conventional processes along with modern processes are being used for the treatment of industrial wastes. Photo-degradation is a modern method used for the degradation of inorganic ions due to its environmentally friendly nature and cost-effectiveness. In a recent study Aluminum oxide (Al2O3) nanoparticles were synthesized via a green approach at different pH by using Cymbopogan citratus (lemongrass) plant extract and these nanoparticles were used for the removal of inorganic ions from wastewater. The nanoparticles of different pH showed different % degradation of the inorganic ions in acidic medium removal of inorganic waste was less, in basic media % degradation was more as compared to acidic media but maximum % degradation was observed in neutral media like that average % degradation 91% and 81% was observed for nitrate and phosphate ions. The maximum absorbance occurred at 212nm and Al2O3 nanoparticles showed absorbance from 210nm-217nm. The R2 values of pseudo1st, 2nd, and BMG models were 0.956, 0.837, 0.7007 0.95, 0.896, and 0.756 for the nitrate and phosphate ions. Characterizations of synthesized particles were investigated by using UV-visible spectroscopy and other analytical methods like X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The statistical analyses were done using Simple Linear regression (SLR).

The present paper investigates flaw strength distributions established using various flexural tests on batches of SiC bar test specimens: 4-point bending as well as 3-point bending with different span lengths. Flaw strength is given by the elemental stress operating on the critical flaw at fracture of a test specimen. Fracture inducing flaws and their locations are identified by fractography. A single population of pores was found to dominate fracture. The construction of diagrams of p-quantile vs elemental strengths was aimed at assessing the Gaussian nature of flaw strengths. Then, empirical cumulative distributions of strengths were constructed using the normal distribution function. Weibull cumulative probability distributions were derived from the mean and the standard deviation using the first moment equation. Agreement was obtained between both Weibull and normal flaw strengths distributions. The cumulative distributions for the different bending tests were predicted satisfactorily from the flaw strength density function using the elemental strength model. Flaw strength distributions that include potential weaker flaws encountered in larger test pieces are extrapolated using the p-quantile diagrams. Implications are discussed about the pertinence of an intrinsically representative flaw strength distribution, about failure predictions, about size effects, and about the significance of flaw spatial distributions.

Aiming to reveal the kinetic characteristics of ceramic ball grinding of fine magnetite comprehensively, two types of ceramic balls ground with the same filling rate and total weight as steel balls were researched. The results show that the breakage rate of ceramic ball grinding is only half of that of steel ball grinding with the same media filling rate. With the same total media weight and the feed size less than 0.212 mm, the breakage rate of the ceramic ball grinding approaches the steel ball grinding and is 21.43% higher than that of the steel ball grinding. The main crushing form of magnetite changed from impact to abrasion in ceramic ball grinding compared with steel ball grinding, which significantly affected the value of the zero-order output constant a. Consequently, there is a noticeable difference in the variation of the parameter β related to the fines generation rate of the ceramic ball grinding compared with the steel ball grinding.

Considering that the electric refrigeration temperature range of 0.94BNT-0.06BT ceramic materials is 100~140˚C, the electric refrigeration performance of the 0.94BNT-0.06BT ceramic material system was modified by LiNbO3 doping to reduce the cooling temperature. As a result, the refrigeration temperature range of the 0.94BNT-0.06BT ceramic material system was lowered to 25~80 ˚C, achieving its cooling effect near room temperature, and in this temperature range, the adiabatic temperature changes ∆T&gt;0.6K.

Abstract: This work for the first time investigated the densification of multi-doping zirconia ceramic body with organic coating powders for solid electrolyte of solid oxide fuel cells via online imaging technology. The densification results show the initial stage plays a key role in the sintering. It can be found the covered organic PVA (polyvinyl acetate) supplies a potential kinetics to the initial densification during sintering. As a result, a kinetic function of densification in the initial stage was suggested. Furthermore, a novel sintering model with six sub-stages is developed for polycrystalline zirconia ceramics. The findings would be a valuable reference for predicting final temperature of sintering, the equivalent strain during the sintering process, as well as optimizing the densification behavior.

Acoustic emission (AE) has proven to be a very useful technique for determining damage in ceramic matrix composites (CMCs). CMCs rely on various cracking mechanisms which enable non-linear stress-strain behavior with ultimate failure of the composite due to fiber failure. Since these damage mechanisms are all micro-fracture mechanisms, they emit stress waves ideal for AE monitoring. These are typically plate waves since for most specimens or applications one dimension is significantly smaller than the wavelength of the sound waves emitted. By utilizing the information of the sound waveforms captured on multiple channels from individual events, the location and identity of the sources can often be elucidated. The keys to the technique are the use of wide-band frequency sensors, digitization of the waveforms (modal AE), strategic placement of sensors to sort the data and acquire important contents of the waveforms pertinent for identification, and familiarity with the material as to the damage mechanisms occurring at prescribed points of the stress history. The AE information informs the damage progression in a unique way which adds to the understanding of the process of failure for these composites. The AE methodology was applied to composites tested in fatigue at different frequencies where identification of when and where AE occurred coupled with waveform analysis leads to source identification and failure progression.

Sharing the same raw material, recycling and composting are in direct conflict with incineration of municipal solid waste in combined heath and power plants. Indeed, waste-to-energy plants in regions with high recycling rates import urban waste from other countries to use otherwise unused capacity, and raise revenues. Using the case of Italy’s second largest and economically most developed region, I discuss the economic viability of municipal solid waste incineration to produce electricity and heath in the context of the increasing role of electricity production from renewable energy sources as well as of the emerging mass-scale uptake of bioplastics. Four lessons and three guidelines aimed to local authorities and policy makers emerge from the present study.

In this study, multi-layer ceramic capacitors (MLCCs) detached from lighting sector's waste electrical-electronic equipment (WEEE) are characterised for the presence of rare earth elements (REEs) and precious metals (PMs). Their digestion was carried out with HNO3 & aqua regia on a heating plate and characterised with the use of inductively coupled plasma optical emission spectroscopy (ICP-OES) & scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX). The contents of REEs and PMs are 0.84 wt% and 0.60 wt%, respectively, and create an economic stored value in MLCCs that is essentially defined by PMs of 98.67% and by Pd 78.37%. The content of the main elements is: Nd 0.366 wt%, Y 0.220 wt%, Dy 0.131 wt%, Ag 0.467 wt%, and Pd 0.105 wt%. The results confirm the need of selective removal and separate recycling process of MLCCs from WEEE drivers.

This study provides a novel method to prepare metal-ceramic composites from magnetically selected iron ore using microwave heating. By introducing three different microwave susceptors (Activated Carbon, SiC, and a mixture of Activated Carbon and SiC) during the microwave process, effective control of the ratio of metallic and ceramic phases has been achieved easily. The effects of the three susceptors on the microstructure of the metal-ceramics and the related reaction mechanisms were also investigated in detail. The results show that the metal phase (Fe) and ceramic phase (Fe2SiO4, FeAl2O4) can be maintained, but the metal phase to ceramic phase changed significantly. In particular, the microstructures appeared as well-distributed nanosheet structures with diameters of ~400 nm and thicknesses of ~20 nm when SiC was used as the microwave susceptor.

Reversible protonic ceramic cells (rPCCs) combine two different operation regimes, fuel cell and electrolysis cell modes, which allow reversible chemical-to-electrical energy conversion at reduced temperatures with high efficiency and performance. Here we present novel technological and materials science approaches, enabling a rPCC with symmetrical functional electrodes to be prepared using a single sintering step. The response of the cell fabricated on the basis of P–N–BCZD|BCZD|PBN–BCZD (where BCZD = BaCe_0.5Zr_0.3Dy_0.2O_3–δ, PBN = Pr_1.9Ba_0.1NiO_4+δ, P = Pr₂O₃, N = Ni) is studied at different temperatures and water vapor partial pressures (pH₂O) by means of volt-ampere measurements, electrochemical impedance spectroscopy and distribution of relaxation times analyses. The obtained results demonstrate that symmetrical electrodes exhibit classical mixed-ionic/electronic conducting behavior with no hydration capability at 750 °C; therefore, increasing the pH₂O values in both reducing and oxidizing atmospheres leads to some deterioration of their electrochemical activity. At the same time, the electrolytic properties of the BCZD membrane are improved, positively affecting the rPCC’s efficiency. The electrolysis cell mode of the rPCC is found to be more appropriate than the fuel cell mode under highly humidified atmospheres, since its improved performance is determined by the ohmic resistance, which decreases with pH₂O increasing.

The difficult current environmental situation, caused by construction industry residues containing ceramic materials could be improved by using these materials as recycled aggregates in mortars, with their processing causing a reduction in their use in landfill, contributing to recycling and also minimizing the consumption of virgin materials. Although some research is currently being carried out into recycled mortars, little is known about their stress-strain (σ-ε); therefore this work will provide the experimental results obtained from recycled mortars with recycled ceramic aggregates (with contents of 0, 10, 20, 30, 50 and 100%), such as: the density, the compression strength, as well as the σ-ε curves representative of their behavior. The values obtained from the analysis process of the results are those of: σ (elastic ranges and failure maximum), ε (elastic ranges and failure maximum), and Resilience and Toughness; in order to finally obtain, through numerical analysis, the equations to predict their behavior (related to their recycled content). At the end of the investigation it is established that mortars with recycled ceramic aggregate contents of up to 20% could be assimilated just like mortars with the usual aggregates, and the prediction equations produced could be used in cases of similar applications.

The global food system has three recognized challenges: (a)increasing the availability of food consumption, (b) reducing food loss, and (c) reducing food waste. The increasing demand for food consumption, increasing quantity of food loss, and corresponding increase in food waste are resulting in serious health, aesthetic, social, economic, and environmental problems due to a lack of appropriate planning and management. Despite its importance, there is no clear, concise, and comprehensive definition of food consumption, loss, and waste. Generally, food consumption, food loss, and food waste are dealt with separately. This article presents a logically constructed ontological framework of food consumption, loss, and waste. It gives equal importance to all three aspects of global food management. The systematic ontological framework is general, and the analysis can be applied to any country. The framework deconstructs the combinatorial complexity of the problem and explicates the pathways to manage the consumption, loss, and waste. The ontological framework encapsulates 19*8*7*4*5*6 = 25,536 possible components of the challenge. A critical analysis based on available data using the framework will help to develop strategies to deal with the problem. It can help to discover the gaps and to find ways to bridge the gaps. It is novel to conceptualize food consumption, loss, and waste together.

The city of Lisbon, has any other capital of a European country, has a large number of issues while managing the waste and recycling containers spread throughout the city. This document presents the results of a study promoted by the Lisbon City Council for trialing LPWAN technology on the waste management vertical under the Lisbon Smart City initiative. Current waste management is done using GSM sensors, and the aim is to use LPWAN to reduce the costs, improve range and reduce provisioning times when changing the communications provider. After an initial study, LoRa was selected as the LPWAN of choice for the trials. The study is composed of multiple use cases at different distances, types of recycling waste containers, placements (underground and surface) and different kinds of waste level measurement LoRa sensors, deployed in order to assess the impact of the different use cases on the LoRa sensor usage. The results shown that the underground waste containers present the most difficult challenge, where the container itself imposes attenuation levels of 26dB on the link budget. The results promoted the deployment of a city wide LoRa network available to all departments inside the Lisbon City Council, and considering the network capacity the network, the network is also available to citizens to be used freely.

Valorization of food and fruit wastes has the potential for the production of sustainable energy and biochemicals. Approximately 70% of the weight of the original jackfruit (Artocarpus heterophyllus L.) fruit is lost during processing as waste in the form of peeled skin and core, both of which have not been utilized and, thus contribute to disposal as well as pollution issues. The major components, cellulose, and hemicellulose, can be biologically transformed easily into bioenergy sources like ethanol, methanol, and butanol; valuable phenolics and biotechnological products like pectin, citric acid, bromelain, ferulic acid, and vanillin; and many other products. These residues can also be utilized as essential sources for the biological transformation process leading to the production of numerous products with added value, such as phenolic antioxidants, phenolic flavor compounds, and organic acids. Thus, the value addition of jackfruit waste can support the sustainable solution towards food and nutritional security. In this way, zero waste can be achieved through novel biorefineries which are critically highlighted in this paper. Furthermore, novel technologies for the conversion of jackfruit wastes are summarized with recent findings.

Self-healing ceramic composites are promising smart materials for high-temperature applications. To better understand their behaviors under service conditions, numerous studies have been performed both experimentally and numerically, and kinetics parameters such as activation energy and frequency factor are reported to be indispensable for investigating healing phenomena. Here, we propose a method for determining the kinetic parameters of self-healing ceramic composites based on the oxidation kinetics model of strength recovery. These parameters are determined by an optimization method using experimental strength recovery data under various healing temperatures and times and microstructural features on the fractured surfaces. Alumina and mullite matrix-based self-healing ceramic composites, such as Al2O3/SiC, Al2O3/TiC, Al2O3/Ti2AlC (MAX phase), and mullite/SiC, were selected as target materials. The theoretical strength recovery behaviors of the cracked specimens obtained from the determined kinetic parameters were compared with the experimental results. The determined parameters are within the previously reported range, and the predicted strength recovery behaviors are reasonably agreed with the experimental values. The proposed method can also be applied to other self-healing ceramics with matrices reinforced with different healing agents to evaluate oxidation rate, crack healing rate, and theoretical strength recovery behaviors for designing self-healing materials used in high temperature applications. Furthermore, the healing ability of composites can be fairly discussed regardless of the type of strength recovery test.

In the present work, the state of the art of the most common additive manufacturing (AM) technologies used for the manufacturing of complex shape structures of graphene-based ceramic nanocomposites, ceramic and graphene-based parts is explained. A brief overview of the AM processes for ceramic, which are grouped by the type of feedstock used in each technology, is presented. The main technical factors that affect the quality of the final product were reviewed. The AM processes used for 3D printing of graphene-based materials are described in more detail; moreover, some studies in a wide range of applications related to these AM techniques are cited. Furthermore, different feedstock formulations and their corresponding rheological behaviour were explained. Additionally, the most important works about the fabrication of composites using graphene-based ceramic pastes by Direct Ink Writing (DIW) are disclosed in detail and illustrated with representative examples. Various examples of the most relevant approaches for the manufacturing of graphene-based ceramic nanocomposites by DIW are provided.

Solid waste management is a global issue that affects every individual living in the world directly or indirectly. Failing to manage the waste properly will cause harm on public health, our natural environment, and even our happiness and prosperity. When asked about the reason behind the failure of third time plastic ban in Bhutan, one of the Bhutanese said it’s because of the lack of cooperation from public to support the move of government. Clean Bhutan, a non-governmental organization (NGO) that aims Zero Waste Bhutan by 2030, has collected around 5,900 metric tons of waste from December 2014 to February 2018. This project will create some awareness regarding the management of waste at individual level when people come in contact with the family of the researcher. It also talks abot how waste management and biodiversity conservation can go side by side.

In this paper, we investigate the structural, microstructural, dielectric, and energy storage properties of Nd and Mn co-doped Ba0.7Sr0.3TiO3 [(Ba0.7Sr0.3)1-xNdxTi1-yMnyO3 (BSNTM) ceramics (x = 0, 0.005, and y = 0, 0.0025, 0.005, and 0.01)] via a defect dipole engineering method. The complex defect dipoles (MnTi"-VO∙∙)∙ and (MnTi"-VO∙∙) between acceptor ions and oxygen vacancies capture electrons, enhancing the breakdown electric field and energy storage performances. XRD, Raman spectroscopy, and microscopic investigations of BSNTM ceramics revealed the formation of a tetragonal phase, increased oxygen vacancies, and reduced grain size with Mn dopant, respectively. The BSNTM ceramics with x=0.005 and y=0 exhibit a high dielectric constant of 2058 and a dielectric loss of 0.026 at 1 kHz. These values gradually decreased to 1876 and 0.019 for x=0.005 and y=0.01 due to the Mn2+ ions at Ti4+-site, which facilitates the formation of oxygen vacancies, and prevents the decrease of Ti4+. In addition, the defect dipoles act as a driving force for depolarization to tailor the domain formation energy and domain wall energy, which provides a high difference between the maximum polarization of Pmax and remnant polarization of Pr (ΔP=10.39 µC/cm2). Moreover, the complex defect dipoles with optimum oxygen vacancies in BSNTM ceramics can provide not only a high ΔP but also reduce grain size, which together improve the breakdown strength from 60.4 to 110.6 kV/cm, giving rise to a high energy storage density of 0.41 J/cm3 and high efficiency of 84.6% for x=0.005 and y=0.01. These findings demonstrate that defect dipoles engineering is an effective method to enhance the energy storage performance of dielectrics for capacitor applications.

The current investigation presents porous ceramic materials prepared of cenospheres prepared by spark plasma sintering. The impact of sintering temperature, mould diameter (20 and 30 mm diameter) and cenosphere size on the properties of the sintered material was investigated. Shrinkage of the samples during sintering started at 900 °C. Sample shrinkage during sintering increases with increasing temperature and decreases with increasing mould size; increasing sample sintering temperature increases the apparent density of all sample series CS 63-150 µm in 20 mm mould from 0.97 to 2.3 g·cm-3 at 1050 - 1300 °C, in 30 mm mould 0.81 - 1.87 g·cm-3 at 1050 - 1200 °C, in 50 mm mould 0.54 - 0.75 g·cm-3 at 1050 - 1150 °C, while CS 150-250 µm in 20 mm mould 0.93 - 1.96 g·cm-3 at 1050 - 1200 °C. Total porosity decreases from 61.5% to 3.9% with increasing sintering temperature from 1050 to 1250 °C, while open porosity reduces at lower temperatures, with closed porosity being highest in samples sintered at 1150 °C. When the sintering temperature increases from 1050 to 1300 °C, the compressive strength of the CS 63-150 samples produced in a 20 mm mould increases from 11 MPa to 312 MPa. These results correlate with the Rice model, which describes an exponential dependence of compressive strength on material porosity and fully dense material compressive strength.

Ceramic composites have good strength, fracture toughness and hardness characteristics and are widely used in industry, medicine. The properties of ceramic composites can be controlled at the production stage by setting the internal structure. This is made possible by the development of additive manufacturing. However, not all properties are well understood, especially dynamic fracture resistance and fracture toughness. In order to predict the mechanical behavior of ceramic composites in the manufacturing phase with a controlled structure under dynamic loads, it is convenient to use methods of numerical analysis. The aim of this work was to investigate the influence of loading speed and internal structure on dynamic resistance and fracture toughness of ATZ nanocomposites. Within the framework of the study physical and mathematical model that is used in computational mechanics of materials is developed. In the paper is shown the influence of the loading rate on the strain rate in the region of the shock transition for materials based on ZrO2 - Al2O3 system. The research shows nonlinear effects under intense dynamic loads in the shown composite materials are bound up with either the processes of self-organisation of deformation modes at the mesoscopic level or the occurrence of martensitic phase transformations in matrix volumes adjacent to the strengthening particles.

This scoping review examines global strategies and enterprises for sustainable solid waste management, with a focus on alternative landfilling approaches. The study collected and analyzed a significant number of documents from different regions, revealing Asia as the major contributor (for the collected documents) (48.7%), followed by North America (24.3%) and Europe (15.8%). Recycling emerged as the most effective alternative waste treatment method, representing 52.3% of the documented approaches, with industrial recycling (22.6%) and residential/non-residential recycling (20.2%) as prominent categories. Food waste was a significant concern across regions, constituting 21.4% of the collected documents. Composting was widely adopted (15.4%) due to its simplicity and benefits for gardening and soil improvement. Other methods like biogas extraction, reusing, raising awareness, incinerating, redistributing, reducing, and fermentation accounted for 13.1% cumulatively. The study highlights the need for tailored waste management solutions based on regional challenges and successful practices. Promoting recycling infrastructure, composting, and waste reduction approaches are crucial to achieving sustainable waste management aligned with SDGs. Collaboration and knowledge-sharing between regions are essential to improve inefficient waste management mechanisms. Integrating the findings into policymaking and industry practices can lead to a more sustainable future with reduced environmental impact.

The proof-of-the-concept of application of low-temperature food waste biochars for the anaerobic digestion (AD) of food waste (the same substrate) was tested. The concept assumes that residual heat from biogas utilization may be reused for biochar production. Four low-temperature biochars produced under two pyrolytic temperatures 300 °C and 400 °C and under atmospheric and 15 bars pressure with 60 minutes retention time were used. Additionally, the biochar produced during hydrothermal carbonization (HTC) was tested. The work studied the effect of a low biochar dose (0.05 gBC x gTSsubstrate-1, or 0.65 gBC x L-1) on AD batch reactors’ performance. The biochemical methane potential test took 21 days and the process kinetics using the first-order model were determined. The results showed that biochars obtained under 400°C with atmospheric pressure and under HTC conditions improve methane yield by 3.6%. It has been revealed that thermochemical pressure influences the electrical conductivity of biochars. The biomethane was produced with a rate (k) of 0.24 d-1, and the most effective biochars increased the biodegradability of FW to 81% in comparison to variants without biochars (75%).

A novel five-surface phosphor-in-ceramic (FS-PiC) for high illumination and excellent color uniformity in larger-scale LEDs for sensor light source application is demonstrated. YAG phosphor (Y3Al5O12:Ce3+) was uniformly mixed with ceramic and sintered at 680°C to form a phosphor wafer. A sophisticated laser engraving was employed on the phosphor wafer to form a saddle-shaped large-scale FS-PiC LEDs. The performance of the FS-PiC LEDs exhibited the illumination of 401lm, average color temperature (CCT) of 5488K±110K, and color coordinates (CIE) of (0.3179±0.003, 0.3352±0.003). In contrast to convention single-surface phosphor-in-ceramic (SS-PiC) LEDs, the performance exhibited the illumination of 380lm, average CCT of 5830K±758K, and CIE of (0.3083±0.07, 0.3172±0.07). These indicated that the performance of the FS-PiC LEDs was higher than the SS-PiC LEDs for illumination, CCT, and CIE of 1.1, 7, and 23 times, respectively. Furthermore, the FS-PiC LEDs demonstrate lower lumen loss of 2% and less chromaticity shift of 5.4x10-3 under accelerated aging at 350°C for 1008 hours, owing to the high ceramic melting temperature of up to 510°C. In this study, the proposed FS-PiC larger-scale LEDs having excellent optical performance and high reliability may be the promising candidates to replace the convention phosphor-in-organic silicone material used in high-power LEDs for the next generation of sensor light sources, display, and headlight applications.

Franklinite-Zincochromite-Gahnite solid solutions have been prepared by ceramic or coprecipitation method and its pigmenting capacity as cool ceramic pigments in different glazes (double and single firing frits and porcelain frit) was studied. XRD, UV-Vis-NIR diffuse reflectance, CIEL*a*b* colour analysis, bandgap measurement and the photocatalytic activity over the Orange II azoic dye were carried out for the characterization of samples. Following criteria of high red colouring capacity and high NIR reflectance at minimum Cr amount, Zn(Fe1.8Cr0.2), Zn(Al1.5Cr0.5) and Zn(Al1.3Cr0.5Fe0.2)O4 turn out to be the optimal compositions for an intense reddish cool pigment. All powders show a direct semiconductor behaviour with bandgap around 2 eV, falling in the visible range (620 nm), and according to literature, the associated photocatalytic activity over Orange II with visible light irradiation is moderate in all cases, but the Franklinite-Zincochromite Zn(Fe1.8Cr0.2) stands out.

Although CAD/CAM ceramics present a promising alternative to metal-ceramic fixed dental prostheses, little is known about their mid- and long-term clinical performance. This systematic review aims to estimate the survival and success rates and describes the underlying complication characteristics for CAD/CAM tooth-supported fixed dental prostheses (FDPs). We systematically searched MEDLINE and Web of Science to find relevant prospective studies with a follow-up of at least one year. We estimated pooled 1-, 5- and 10-year survival and success rates by combining the collected data in a Poisson regression model. Descriptive statistics were conducted to evaluate the distribution of failures and complications in the included studies. Risk of bias for the included studies was assessed with an adapted checklist for single-arm trials. Pooled estimated 1-, 5-, and 10-year survival rates ranged from 93.80% to 94.66%, 89.67% to 91.1%, and 79.33% to 82.20%, respectively. The corresponding success rates, excluding failures but including any other types of intervention, were 94.53% to 96.77%, 90.89% to 94.62%, and 81.78% to 89.25%. Secondary caries was the most frequent cause of failure, followed by chipping of the veneering. The most common cause of complication, excluding failures but requiring intervention, was chipping of the veneering. Risk of bias was generally acceptable for the included studies, with 7 studies associated with low risk of bias, 8 studies with a moderate risk of bias, and 3 studies with serious risk of bias. The current meta-analysis on CAD/CAM supported FDPs revealed satisfying survival and success rates for up to 10 years of exposure. More prospective studies focusing on long-term performance are needed to strengthen the evidence currently available in the literature.

Selection of co-belonging fragments from the numerous ceramic findings of an archaeological excavation remains a difficult process of questionable effectiveness, based exclusively on the experience and patience of the conservators. While the screening of the fragments is a central prerequisite and the most important stage of the process of vase reconstruction, established methods based on scientific criteria and guaranteed efficiency for the detection of co-belonging ceramic fragments suggested in the bibliography, do not exist. On the contrary, for methods dealing with the assembly of vases from co-belonging fragments, which is a secondary process that can be done more easily and effectively in an empirical way, there exist numerous studies based on fragment morphology. However, even these are also not implemented because of the time requirements, sheer volume and complexity of the proposed methods, in order for them to be applicable in practice. The proposed methods in this paper are based on thermoremanent magnetization (A/m), which is calculated from the weak magnetic field measurements by a fluxgate-sensor/magnet apparatus forming a three-dimensional orthogonal system. Experimental measurements from fragments of 6 vases show that the magnetization magnitude of co-belonging fragments display similar values, despite the magnetic anisotropy of the ceramic material, since these belong to vases that are made of the same clay and fired under the same conditions. This is the criterion for finding ceramic fragments of the same vase from archaeological excavations. The thermoremanent magnetism directionality of fragments, which is aligned along the geomagnetic field at the same place and time during the vase firing process, as it is configured by their rotational symmetry, defines the position of the fragments on the body of the 6 vases. The shape of the original vase can be reconstructed when only a few non adjacent fragments are available. The proposed measurement apparatus can be used for the construction of a useable portable magnetometer specialized for ceramic surface measurements to achieve the above objectives.

Background: Antibiotic-containing carrier systems are one option that offers the advantage of releasing active ingredients over a longer period of time. In vitro sustained drug release from a carrier system consisting of microporous β-TCP ceramic and alginate has been reported in previous works. Alginate dialdehyde (ADA) gelatin gel showed both better mechanical properties when loaded into a β-TCP ceramic and higher biodegradability than pure alginate. Methods: Dual release of daptomycin and BMP-2 was measured on days 1, 2, 3, 6, 9, 14, 21, and 28 by HPLC and ELISA. After release, the microbial efficacy of the daptomycin was verified and the biocompatibility of the composite was tested in cell culture. Results: Daptomycin and the model compound FITC protein A (n=30) were released from the composite over 28 days. A Daptomycin release above the minimum inhibitory concentration (MIC) by day 9 and a burst release of 71.7 ± 5.9 % were observed in the loaded ceramics. Low concentrations of BMP-2 were released from the loaded ceramics over 28 days.

As the additive manufacturing industry grows, it is compounding the global plastic waste problem. Distributed recycling and additive manufacturing (DRAM) offers an economic solution to this challenge, but it has been relegated to either small-volume 3D printers (limiting waste recycling throughput) or expensive industrial machines (limiting accessibility and lateral scaling). To overcome these challenges, this paper provides proof-of-concept for a novel open-source hybrid 3D printer that combines a low-cost hanging printer design with a compression screw-based end-effector that allows direct extrusion of recycled plastic waste in large expandable printing volumes. Mechanical testing of the resultant prints from 100% waste plastic, however, showed that combining challenges of non-uniform feedstocks and a heavy printhead for a hangprinter reduced the strength of the parts compared to fused filament fabrication. The preliminary results are technologically promising, however, and provide opportunities to improve on the open source design to help process the volumes of waste plastic needed for DRAM to address the negative environmental impacts of global plastic use.

Abstract: In order to accelerate deployment of distributed recycling by providing low-cost feed stocks of granulated post-consumer waste plastic, this study analyzes an open source waste plastic granulator system. It is designed, built and tested for its ability to convert post-consumer waste, 3-D printed products and waste into polymer feedstock for recyclebots of fused particle/granule printers. The technical specifications of the device are quantified in terms of power consumption (380 to 404W for PET and PLA, respectively) and particle size distribution. The open source device can be fabricated for less than USD$2000 in materials. The experimentally-measured power use is only a minor contribution to the overall embodied energy of distributed recycling of waste plastic. The resultant plastic particle size distributions were found to be appropriate for use in both recyclebots and direct material extrusion 3-D printers. Simple retrofits are shown to reduce sound levels during operation by 4dB-5dB for the vacuum. These results indicate that the open source waste plastic granulator is an appropriate technology for community, library, makespace, fab lab or small business-based distributed recycling.

This study aimed to investigate the effect of reducing the amount of organic waste on the weight of cats in Tehran. The weight of 4192 cats was measured from spring 2016 to the end of winter 2020. They were classified into 6 age groups, 2 gender groups, and 13 geographical areas. Their weight was measured for 48 months (16 seasons). The statistical parameters analysis showed no weight loss in 2017, but since 2018, cats have been losing weight every year. They had lost about 178g of their weight in 2018. The sharpest annual decrease was observed in 2019 when about 301g of weight loss was recorded. In the winter of 2020, 115g of weight loss took place. In the spring of 2017, no weight change was observed, but in the spring of 2018, the cats lost 155g of their weight. Their weight loss intensified in the spring of 2019 and about 299g of weight loss was observed. In the summer of 2017, as in the spring of the same year, no weight loss was recorded, but for the summer of 2018, the weight loss was evident and about 205g of the weight of the cats had been reduced. The weight loss in the summer of 2019 not only continued but intensified and about 304g of weight loss was recorded for cats. Weight change was not observed in the fall of 2017 as in the spring and summer of the same year. In the fall of 2018, weight loss was recorded for cats. They had lost about 324g of their weight in the fall of 2018. Also, they experienced a weight loss of about 218g in the fall of 2019. During the spring, summer, and autumn of 2017, no weight loss was observed in the cats for the winter of 2018, but in the winter of 2019, the cats faced the most severe weight loss (seasonally). They lost about 401g of weight in the winter of 2019. Of course, in the winter of 2020, about 186g of weight loss was observed in cats. The results showed that female cats did not lose weight in 2017 but experienced weight loss in 2018 with a weight loss of 181g. The weight loss of females intensified in 2019 and 294g of weight loss was recorded. Female cats lost 186g of their weight in the winter of 2020. Male cats did not lose weight like female cats in 2017. But in 2018, a weight loss of 166g was observed in male cats. The weight loss of male cats continued in 2019 and 311g of weight loss was recorded for them. However, in 2020, unlike females, weight loss was not observed in male cats. It can be said that both sexes lost more weight in the winter of 2019 than in other seasons. In 2017, weight loss was observed only for the region of 10, and in the same year, weight gain was recorded for the region of 15. But in 2018, except for regions 3, 4, 15, and 19, weight loss was observed in other regions. In 2019, the weight loss of cats spread and weight loss was observed in all regions except the region of 12. In winter 2020, weight loss was recorded only in the region of 4. In the end, it can be concluded that the weight of cats has decreased since the spring of 2018 because the beginning of the decrease in the amount of organic waste has been recorded since the winter of 2018. So, there is a direct relationship between the weight of cats and the amount of organic waste (access to food). The amount of garbage has been decreasing since the winter of 2018, and the average weight of cats has also been decreasing since the spring of 2018 due to the decrease in access to food.

The issue of sustainability has long been the subject of interest of the architecture engineering and construction sector. All three aspects of sustainability - economic, environmental and social - can be affected through appropriate construction waste management. Construction and demolition waste (CDW) is one of the largest worldwide waste streams, therefore it is given great attention by all stakeholders (investors, contractors, authorities, etc.). Researches have shown that one of the main barriers to insufficiency CDW recovery is inadequate policies and legal frameworks to manage CDW. It is also one of the EU's environmental priorities. Aim of the article is to confirm the economic potential of construction and demolition waste audit processing through case study. A pre-demolition waste audit has been processed for unused building of shopping center in the town Snina in Slovakia. Subsequently, a comparison of economic parameters (waste disposal costs and transport costs) of recommended CDW management was performed. This comparison confirmed the economic benefits of environmentally friendly construction waste management methods according to the waste audit results, which will also increase the sustainability of construction projects. In addition, the cost parameters of selected waste disposal methods could be another dimension of building information modelling.

To understand the enhanced protection mechanism of CoCrNiAlY-YSZ-LaMgAl11O19 dou-ble-layer ceramic coating with aluminum plating, a finite element simulation method was used to simulate the distribution of thermal stress in the coating in all directions. The results show that in the air exposure of the un-aluminized coating, high temperature causes a large radial thermal stress on the surface of the LaMgAl11O19 (LMA) layer, and it increases with the increase in temperature, which is the main reason for the initiation of axial cracks. After arc aluminum plating, the aluminum plating layer effectively inhibited the volume shrinkage of the coating through good adhesion to the coating and internal diffusion, the thermal stress of the coating was considerably reduced, and the CoCrNiAlY-YSZ-LMA coating had an effective enhancement and protection effect; however, there was still a certain amount of shear thermal stress inside the LMA layer, the top of the crack, and the bottom of the crack. This thermal stress caused the initi-ation of radial microcracks in the LMA layer, which also becomes a risk point for the failure of the aluminum coating.

There are various approaches to managing polyethylene terephthalate waste, including methods for recycling PET. However, at present, only the cleanest wastes that can already be efficiently recycled using known methods are considered in the scientific literature. The study aims to look at other forms of polyethylene terephthalate waste that pose a challenge: low quality PET flakes, polyester tire cord, PET dust and prepolymer waste. The waste was characterized by FTIR spectroscopy, viscosimetry, differential scanning calorimetry, laser diffraction and sieve analysis. The findings describe the composition and properties of various forms of polyethylene terephthalate waste. Low quality PET flake waste and polyethylene terephthalate dust have been shown to be suitable for all chemical recycling methods. When recycling waste polyester tire cord, it is difficult to completely separate the rubber, so its presence in the final product must be taken into account. The most promising way to process a prepolymer is its depolymerization by hydrolysis, alcoholysis or glycolysis to produce monomers for the synthesis of PET, similar in properties to the primary one.

The consistent and continuous growth in the world’s population is creating many challenges for public policymakers in the different life areas, including dealing with the increasing amounts of waste that are generating problems involving air and land pollution and a shortage of land for waste disposal. This study presents the results of public policy on managing municipal waste, as manifested in the quantity and rate of waste collected throughout Israel in recent years and disposed of in the various landfills and in analysis of the political and economic factors affecting this policy. The study combines a quantitative and qualitative approach, where the quantitative study includes analysis of statistical data based on information from the Central Bureau of Statistics, the Ministry of Environmental Protection, the Ministry of Finance, and others, and the qualitative study relies on reading and analyzing primary documents of the different government ministries on Israel’s waste disposal policy and information in the media on this issue. The research findings attest to an increase in the amount of municipal waste dumped in Israel, a merely slight decrease in the rate of landfilling as a proportion of all municipal waste disposal, and a merely slight increase in the rate of municipal waste recycled in recent years. The research conclusions stress the effects of the landfill levy and the Cleanliness Maintenance Fund on one hand, and of the government instability in the Ministry of Environmental Protection, the positivist policy embraced by decision makers in the Ministry of Environmental Protection, and the power struggles between Israel’s different ministries on the other, as the respective economic and political factors affecting Israeli policy on municipal waste management.

The treatment, disposal, and resource utilization of waste mud are challenges for engineering construction. This study investigates the road performance of waste mud–solidified soil and reveals the mechanism of how solidifying materials influence the strength and deformation characteristics of waste mud. Waste mud, collected from a highway reconstruction project, was mixed with ordinary Portland cement as a solidifying material. Unconfined compressive strength tests, consolidated undrained triaxial shear tests, resonant column tests, and consolidation compression tests were conducted to evaluate the solidification effect. The test results show that with an increase in cement content from 5% to 9%, the unconfined compressive strength of the waste mud–solidified soil increased by over 100%, the curing time was extended from 3 days to 28 days, and the unconfined compressive strength increased by approximately 70%. However, an increase in initial water content from 40% to 60% reduced the unconfined compressive strength by 50%. With the increase of cement content from 5% to 9%, the cohesion and friction angles increased by approximately 78% and 24%, respectively. The initial shear modulus under dynamic shear increased by approximately 38% and the shear strain corresponding to a damping ratio decay to 70% of the initial shear modulus decreased by nearly 11%. The compression coefficient decreased by approximately 55%. Scanning electron microscopy and X-ray diffraction tests showed that a higher cement content led to the formation of more hydration reaction products, especially an increase in the content of AlPO4. The bonding material between soil particles significantly increased, exerting a bonding and filling effect on soil particles and firmly adhering them together. Consequently, the strength of the waste mud–solidified soil increased significantly while its compressibility decreased.

The article provides an overview of nanocomposites and microelectronic elements used in space electronics and radiation control systems of nuclear reactors. Only those nanocomposites and microelectronic elements are taken into account that improve their characteristics in radiation fields or remain indifferent when exposed to ionizing radiation. Considering the chemical composition of the materials of these nanocomposites and microelectronic elements, it is analyzed from which radioactive materials (RM) obtained by recycling radioactive waste (RW) such composites and microelectronic parts can be made. Thus, an alternative way of radioactive waste disposal is proposed, when these wastes are used in the form of microelectronic elements designed to operate under conditions of cosmic radiation.

Introduction: Pharmaceutical products are inevitable for human health. Owing to the growing need for pharmaceuticals, pharmaceutical companies introduce drugs annually into the market in addition to the extensive collection of existing pharmaceutical products. Households, farms, health facilities, and pharmaceutical industries release pharmaceutical waste into the environment at low concentrations through routine pharmaceutical use, damage, and expiry. The effects of active pharmaceutical ingredients (API) on non-target species in the environment are not known. Over the years, pharmaceuticals such as diclofenac and ibuprofen in trace amounts have been detected in public water systems, ground and surface water. Unwanted medicines should be safely disposed of at a reduced financial cost to mitigate the public and environmental health risks. Lack of general knowledge of how to dispose of unused pharmaceuticals leads to improper disposal resulting in accidental toxicity, rising healthcare costs, landfills pilfering/scavenging, water supply pollution, anti-microbial resistance, and death. To mitigate such effects, pharmacists should raise public awareness about safe disposal practices. Objective: This review aims to examine the sources of pharmaceutical waste, disposal costs, secure disposal methods, the effects of inappropriate disposal, and the role of pharmacists in the disposal. Method: The information on the stated objectives was gathered from available sources through a comprehensive literature review. Conclusion: Many countries contain tons of pharmaceutical waste that are expensive to destroy. Because of improper disposal, pharmaceutical waste has been found at trace amounts in drinking and surface water. A practical, environmentally sustainable approach to pharmaceutical waste management, with policies and guidelines, and public awareness campaigns, are necessary to address the problem of safe waste disposal. The national drug regulatory bodies should conduct environmental risk assessment resulting from the disposal of unwanted pharmaceuticals. Pharmacists should facilitate extensive training on sustainable drug use and proper pharmaceutical waste disposal at all levels to reduce the risks associated with improper disposal. Reduction of pharmaceutical waste generation at each step of a drug’s lifecycle, implementing takeback options, collection at approved sites, and modern technology to treat wastewater are highly recommended to reduce the effects of unwanted pharmaceuticals on human health and the environment.

The phase composition design principle is introduced to obtain balanced properties of ionic conductivity and thermo-tolerant for zirconia solid electrolytes used in solid oxide fuel cells (SOFCs). The zirconia ceramic solid electrolytes are fabricated by two-step free sintering. With increasing Y/Mg ionic ratio from 1.78:1 to 1.88:1, the content of monoclinic phase fluctuates little (±3%). The ionic conductivity, including the total electrical resistance; grain electrical resistance and grain boundary electrical resistance at 1223K, are all gradually declining with the increasing of Y/Mg ionic ratio. Furthermore, the enrichment of Mg ion in grain boundary acts as a disincentive to grain boundary ionic conductivity. In addition, the maximum total equivalent conductivity at 1223K in this study reaches to 0.143 Scm-1 which can compare with that of certain YSZ. It will be beneficial to SOFCs application profited from increasing ionic conductivity of ceramic solid electrolytes.

Solid waste management is challenging in many countries, especially developing economies. The impacts of the pandemic continue to be felt and have indicated secondary impacts on waste management. This work draws on data on household solid waste (HSW), healthcare waste (HCW), and recyclables collected in the Rio de Janeiro municipality, analyzed from January 2018 to December 2022. As expected, the collection of HCW in Rio de Janeiro municipality experienced a noticeable increase in 2020 and 2021, with an average of 46.9 tons and 54.3 tons collected, respectively. Notably, 2021 saw a significant 30% increase compared to 2019 (p-value<0.001). No significant difference was observed in recyclables collected from 2018 to 2021. The average recyclable amount was 3,638 and 3,747 tons per month in 2020 and 2021. In contrast, the monthly amount was equal to 4,819.5 tons in 2022, representing an increase higher than 32% compared to previous years (p-value<0.05). Our findings can be used to adapt and improve waste systems to cope with similar emergency scenarios in the future, serving as a template for municipalities with similar challenges.

This paper focuses on the highly radioactive, long-lasting nuclear waste produced by the currently operating fission reactors and on the way to deal with the sensitive issue of spent fuel reprocessing. The review includes a short description of the fission process and a detailed analysis of the more hazardous radioisotopes produced either by secondary reactions occurring in the nuclear installations or by decay of the fission fragments. Also outlined are the strategies presently adopted to minimize the harmfulness of the nuclear waste to be disposed and discussed advanced options and possible solutions proposed for the recycling of the used fuel and for the reusing of some technologicaly relevant radioisotopes.

There are four categories of medical waste that cannot be mixed as this will cause serious problems such as environmental pollution or infection. In the past, the classification of medical waste often involved a lot of human and material resources to process, with workers at risk of exposure to infectious substances. Therefore, an augmented reality (AR) and artificial intelligence (AI) medical waste classification system and method were developed. This innovative medical waste classification system and method combines AR and AI identification technology to reduce the risk of manual judgment errors by clinical staff when handling medical waste.

Starting from an original survey conducted in eight countries in 2021 (Canada, China, Germany, Italy, Russia, Spain, UK, and USA), this research explores the relationship between household food waste and dietary habits in a cross-country comparative perspective. 8,000 questionnaires were recorded from samples representative of adult population of each country through an online survey conducted between the 13th and the 24th of August. The questionnaires were built on the work of Waste Watcher International Observatory on Food and Sustainability, an international observatory of social, behavioral and lifestyles dynamics behind household food waste. Relationship between per capita self-reported amount of food waste (expressed in kilocalories) and self-declared dietary habits (Traditional, Healthy and Sustainable, Vegetarian, Smart, Confused) was estimated using multiple linear regression models. Results show that Smart diets are associated with higher values of food waste in Canada, Spain, UK and USA. Vegetarian diets are associated to lower food waste values in China, Germany, UK and USA but not in Italy, Russia and Spain. Since the share of population adopting a Smart diet is on average 2.7% of the sample, interventions for food waste reduction should focus on this specific type of consumers, often associated to larger amounts of food waste.

Biocompatibility of ceramic materials in CaO-P2O5 system was investigated using different methods, including in vitro and in vivo tests. Ceramics based on calcium pyrophosphate Ca2P2O7 were obtained by annealing cement-salt stone from highly concentrated hardening suspensions (HCHS). Cement-salt stone was prepared using powder mixtures of calcium citrate tetrahydrate Ca3(C6H5O7)2·4H2O and monocalcium phosphate monohydrate (MCPM) Ca(H2PO4)2·H2O. These salts were mixed with each other in such a way that calcium pyrophosphate and calcium polyphosphate were present in the final ceramic product in the following weight ratios: Ca(PO3)2/Ca2P2O7 = 0/100; 5/95; 10/90 and 20/80. Distilled water was added to a homogenized powder mixtures of Ca3(C6H5O7)2·4H2O and Ca(H2PO4)2·H2O by a water/solid ratio of 0,5 by weight. The obtained suspensions were shaped using silicon molds and left to dry in air for a week. The phase composition of the obtained samples of cement-salt stone was represented by brushite CaHPO4·2H2O, monetite CaHPO4, calcium citrate tetrahydrate Ca3(C6H5O7)2·4H2O and monocalcium phosphate monohydrate Ca(H2PO4)2·H2O. According to the XRD data, the phase composition of ceramic materials after annealing in the temperature range of 800-1000 0C was mainly represented by the β-Ca2P2O7 phase. In vivo tests shown that obtained ceramic materials can be recommended for regenerative treatments for bone defects.

Advanced ceramics are recognized as key enabling materials possessing combinations of properties not achievable in other material classes. They are characterized by very high thermal, chemical and mechanical resistance and also usually have a lower density than metals. These properties predestine ceramics for many different applications, especially space applications.In the aerospace sector aerospike nozzles promise performance and application advantages compared to classic bell nozzles but are also inherently more complex to manufacture due to their shape. AM methods drastically simplify or even enable the fabrication of those complex structures while minimising the number of individual parts. The applicability of ceramic AM (“CerAMfacturing”) on rocket engines and especially nozzles is consequently investigated in the frame of the “MACARONIS” project, a cooperation of the Institute of Aerospace Engineering at Technische Universität Dresden and the Fraunhofer Institute for Ceramic Technologies and Systems (IKTS) in Dresden. The goal is to develop novel large size aerospike thrust nozzles including areas of highest resolution and fineness. Finding a suitable AM process that enables the realisation of both aspects is extremely challenging. One possibility could be the hybridization of shaping methods, in that case CerAM VPP (ceramic additive manufacturing via vat photopolymerization) and CerAM FFF (ceramic additive manufacturing via fused filament fabrication) in combination with sinter joining. This contribution focuses on the high resolution CerAM VPP process, in particular the development, characterization and testing of a new photoreactive Al₂O₃ suspension validated by AM of novel aerospike nozzles.

The regional recycling of plant waste from municipal green space maintenance, private households and private gardens is traditionally carried out in partially open composting plants. In addition to climate-relevant gases, dust, germs and odours are emitted. Compared to aerobic rotting the pyrolysis at higher temperatures and/or reforming offers industrial utilisation of plant based biowaste, with additional availability of energetic by-products. A high-quality plant charcoal derived from a pilot plant is used in a one-year field trial to establish a theoretical comparability with substrates from composting. The advantages and disadvantages of composting and high-quality pyrolysis is shown for comparison, to foster further investigation in advanced technologies for production of plant charcoal aiming the sequester of biogenic Carbondioxide.

The copper end paste used in multilayer ceramic capacitors sintered in nitrogen atmosphere will lead to carbon residue of organic vehicle, which will lead to the reduction of electrode conduc-tivity and high scrap rate. With an attempt to leave no residue in the sintering, the compatibility of solvents and thickeners should be improved because it has an important influence on the hi-erarchical volatilization and carbon residue of organic vehicles. In this work, the volatility of different solvents was compared and several solvents were mixed in a definite proportion to prepare an organic vehicle with polyacrylate resins. The hierarchical volatility and solubility parameters of mixed solvents were adjusted effectively by changing proportions of different components, the thermogravimetric curves of resins and organic vehicles were measured by thermogravimetric analyzer, the effect of solubility parameter on the dissolvability of resins in the solvent and the residual of organic vehicles were studied. Results showed that the hierar-chical volatilization of solvents can be obtained by mixing different solvents; the intrinsic vis-cosity of the organic vehicle is higher and the thermal decomposition residue of polyacrylate resins is lower when the solubility parameters of mixed solvents and polyacrylate resins are closer. The low residual sintering of organic vehicles can be achieved by using the mixed solvent with hierarchical volatility and approximate solubility parameters as resins.

In this study on volume determination in waste sorting facilities, we evaluate the effectiveness of ultrasonic sensors and address waste-material-specific challenges. Although ultrasonic sensors offer a cost-effective automation solution, their accuracy is affected by irregular waste shapes, varied compositions, and environmental factors. Notable inconsistencies in volume measurements between storage bunkers and conveyor belts underscore the need for a comprehensive approach to standardize bale production. With prediction reliability being constrained by limited data sets, undocumented modifications to machine-settings and sensor failures, this task renders a challenging application area for Machine Learning. We explore related research and present dataset analyses from three distinct waste sorting facilities in Europe, addressing issues as sensor usability, data quality and material specifics. Our analysis suggests promising strategies and future directions for enhancing waste volume measurement accuracy, ultimately aiming to advance sustainable waste management.

: One of the challenges facing operations management is the design, choice and imple-mentation of action plans adapted to the magnitude of the deviations of the variables of an industrial process. Making conscious and quick decisions is crucial to achieving im-provements in productivity. This will be achieved if the organization's internal and external communication model is strategically designed, considering specific cultural factors and the symmetry or asymmetry required in the communication model. However, how do we organize ourselves and through what channels do we communicate within a production process to generate Big Data that combines data from technologies and the perception, comprehension and projection of experienced humans? Our purpose is to create an operations management model that facilitates the incorporation of technology, allows a prompt response to failures, and promotes the sustainability of processes, without losing sight of its alignment with the organizational strategy. The developed model was implemented in an operations management team, following the guidelines of an action researcher methodology. This resulted in the design of an operations management model and a detailed methodology for its implementation, achieving sig-nificant improvements in the metrics of the current process, making it a success story.

Waste management is a significant issue that Indonesia must face. The presence of waste will always exist as long as life continues. One of the main challenges in waste management is the proper separation of organic and inorganic waste. As a solution to address this issue, the Ministry of Environment has made efforts to develop Waste Banks. However, it also creates new problems related to manual data collection, lack of monitoring by the community in implementing waste management activities, and a lack of specific reports regarding waste management conducted by officers. We propose the creation of a website using the Agile Development SDLC method. This website involve several steps and incorporate functions for data digitalization and expedited data collection, such as the addition of QR Code functionality, Monthly Reporting Function, and enhanced data security. The method used in this research is Agile Development. The application has been developed with a user-friendly interface and the latest web development technologies to ensure smooth performance. Overall, the web-based application for organic and inorganic waste using Laravel is an important step to promoting sustainable waste management practices.

The Metabolic Food Waste [MFW (kg of food)], first time developed in 2016 as a new indicator by Serafini and Toti, indicates the amount of food consumed over the nutritional requirements and the impact of this overconsumption on the environment. It is necessary to identify the causes and to develop potential methods to prevent and reduce MFW, at the same time with increasing consumer awareness about unsustainable diets and changing diet habits toward more environmentally conscious consumption patterns. By analysing and corroborating external data available for food waste, nutritional requirements, environmental impact of food waste and consumer behaviour, we identified as primary causes for MFW the lack of nutritional education and little understanding of the nutritional requirements amongst all categories of consumers, no access to appropriate food resources or reduced availability of fresh produced food. We conclude that for the quantification of the negative impact of MFW on both the environment and human health, we need a decisive action to raise consumer awareness for healthy and sustainable diets, together with an uniform worldwide distribution of the nutritious food.

In this study, 12 organic waste materials were subjected to TG/DTG thermogravimetric analysis and DSC calorimetric analysis. These analyses provided basic information about thermochemical transformations and degradation rates during organic waste pyrolysis. Waste materials were chosen to cover the most abundant waste that can be found in the municipal solid waste stream. Based on TG results, kinetic parameters according to Coats–Redfern method were determined. The pyrolysis activation energy was the highest for cotton 134.5 kJ∙(mol∙K)-1 and the lowest for leather 25.2 kJ∙(mol∙K)-1. The DSC analysis showed number of transformations occurred during pyrolysis for each material. For each transformation, normalized energy required for transformation, or released during transformation were determined and then summarized to present energy balance. The study found that only for three waste materials: PET (-220.1 J⸱g-1), leather (-66.9 J⸱g-1), and chicken meat (-130.3 J⸱g-1) energy balance was negative, while the highest positive balance value was found for potato peelings (367.8 J⸱g-1). The obtained results may be applied for the modelling of energy and mass balance of municipal solid waste pyrolysis.

This work aims to investigate the effect of process temperature and catalyst content by thermochemical degradation of municipal solid waste (MSW) fraction (organic matter + paper + plastic) on the yield of reaction products (bio-oil, biochar, H2O and gas), physicochemical properties and chemical composition of bio-oils, as well as on the morphology and crystalline phases of biochar in laboratory scale. The organic matter, paper and plastic segregated from the gravimetric composition of total waste sample were subjected to the pre-treatments of drying, crushing and sieving. The experiments were carried out at 400, 450 and 475 °C and 1.0 atmosphere, and at 450 °C and 1.0 at-mosphere, using 5.0, 10.0 and 15.0% (wt.) of FCC zeolite, bath mode, using a laborato-ry scale glass reactor. The bio-oil was characterized for acidic value. The chemical functions present in the bio-oil identified by FT-IR and the composition by GC-MS. Biochar was characterized by SEM/EDS and XRD. Thermal pyrolysis of the MSW frac-tion (organic matter + paper + plastic) shows bio-oil yields between 9.44 and 9.24% (wt.), aqueous phase yields between 21.93 and 18.78% (wt.), solid phase yields between 67.97 and 40.34% (wt.) and gas yields between 28.27 and 5.92% (wt.). The yield of bio-oil decreases with increasing process temperature. For the experiments using FCC, the biochar and gas yields increase slightly with the FCC content, while that of bio-oil de-creases and the H2O phase remains constant. The GC-MS of bio-oils identified the presence of hydrocarbons and oxygenates, as well as nitrogen-containing compounds, including amides and amines. The acidity of the bio-oil increased with increasing temperature and with the aid of FCC as a catalyst. It has been identified the presence of hydrocarbons within bio-oil by addition of FCC catalyst due to the deoxygenation of carboxylic acids, followed by decarboxylation and decarbonylation reactions, producing aliphatic and aromatic hy-drocarbons.

The introduction of organic and inorganic substances to the environment is a result of human activities such as agriculture, domestic and industrial wastewater which leads to pollution. Treatment processes of these wastewaters are being conducted globally to eliminate easily settled materials and recover nutrients in an attempt to release clear and apparently clean effluent into natural waters. Lack of removing inorganic nitrogen and phosphorus nutrients is the greatest cause of eutrophication in water bodies which inhibits the life of other organisms as well as pose a threat to human life and loss of the economy. Different technologies have been applied and are being developed to recover nutrients as well as heavy metals from wastewater to meet the permissible limits before discharging effluents. Wastewater treatment using microalgae offers an opportunity to provide tertiary bio-treatment and production of valuable biomass. Microalgae use the available inorganic nitrogen and phosphorus for their growth which are then harvested for various uses. Additionally, they have the ability to remove heavy metals and some toxic compounds. The main specific microalgae species in this study is the Chlorella sorokiniana with the Aequorea victoria jellyfish This paper reviews some of the wastewater treatment processes and focus on the use of microalgae and some of the shortcomings of the technologies and how they can be improved to achieve maximum nutrient recovery economically with low energy demand.

Evidence regarding the effect of the onlay preparation design for different CAD/CAM restorative materials considering the preservation of cusps is lacking. Molars were 3D modeled in four preparation designs for onlay restoration: traditional design with functional cusp coverage (TFC), non-retentive design with functional cusp coverage (NFC), traditional design with non-functional cusp coverage (TNFC), non-retentive design with non-functional cusp coverage (NNFC). Restorations were simulated with two CAD/CAM restorative materials: LD – lithium disilicate (IPS e.max CAD) and RC - resin composite (GrandioBloc). A 100 N axial load was applied to the occlusal surface simulating the centric contact point. Von Mises (VM) and maximum principal (Pmax) stresses were evaluated for restorations, cement layer and dental substrate. The non-retentive preparation design reduced the stress concentration in the tooth structure in comparison to the conventional retentive design. For LD onlays, the stress distribution on the restoration intaglio surface showed that the preparation design as well as the prepared cusp, influenced the stress magnitude. The non-retentive preparation design provided better load distribution in both restorative materials and more advantageous for tooth structure. The resin composite restoration on non-functional cusp is recommended when functional cusp is preserved, in order to associate conservative dentistry and low stress magnitude.

Talking about sustainable development refers mainly to the environmental sphere, but the concept is much broader and also takes into account the social and economic conditions. The concept of sustainability, in this sense, is linked to the compatibility between the development of economic activities, the related social phenomena, and the protection of the environment. Therefore, the ability to balance social, economic and environmental sustainability is the very meaning of the concept of sustainable development. Firms that choose to develop policies and strategies to enhance and pursue sustainable development in the medium to long term have the burden of having to quantitatively document the improvements in production processes with the aim of sustainable development. As a result, one of the biggest challenges for European industry is to introduce sustainability principles into business models leading to competitive advantage. This is particularly important in raw material and energy intensive manufacturing sectors such as the ceramic industry. The present state of knowledge lacks a comprehensive operational tool for industry to support decision-making processes geared towards sustainability. In the ceramic sector, the economic and social dimensions of the product and processes have not yet been given sufficient importance. Moreover, the traditional research on industrial districts lacks an analysis of the relations between firms and the territory with a view to sustainability. Finally, the attention of scholars in the field of economic and social sustainability, has not yet turned to the analysis of the Sassuolo district. Therefore, in this paper we introduce the Life Cycle Sustainability Assessment (LCSA), as a method that can be a suitable tool to fill this gap, because through a mathematical model it is possible to obtain the information useful for decision makers to integrate the principles of sustainability both at the microeconomic level in enterprises, and at the meso-economic level for the definition of economic policies and territorial governance. Environmental and socio-economic analysis was performed from the extraction of raw materials to the packaging of the product on different product categories manufactured by the Italian ceramic industries of the Sassuolo district (northern Italy). For the first time the LCSA model, usually applied to unitary processes, is extended to the economic and industrial activities of the entire district, extending the prospect of investigation from the enterprise and its value chain to the integrated network of district enterprises.

In the face of 21st-century environmental challenges, including climate change, migration pressures, and waste disposal issues, certain healthcare sectors, notably dentistry, pose a significant global environmental footprint with concerns about carbon emissions and waste production. This scoping review delves into the paradox that healthcare, while dedicated to safeguarding health, inadvertently contributes to environmental degradation through waste accumulation and disposal. The analysis of relevant pertinent literature emphasizes the imperative for an environmentally sustainable approach to dental waste measurement, disposal methods, and comprehensive education for stakeholders. Aligned with the World Conference on Sustainable Development and the United Nations' 2030 Agenda, the study adhered to PRISMA-ScR scoping review guidelines and Institute of Medicine's recommendations. The study utilized Medline/PubMed and international organization websites for data retrieval, employing Boolean operator queries in Medline. A systematic literature analysis identified six cross-sectional studies (2004-2018) highlighting variations in dental waste composition due to the lack of standardized identification methods. This heterogeneity underscores the need for a proposed research model, emphasizing comprehensive methodologies and healthcare staff training in waste management. The study advocates for environmentally conscious dental practices, contributing to broader sustainable healthcare goals through sharing of a research protocol for dental solid waste management.