This paper presents a piezoresistive pressure sensor with a shield layer for improved stability. Compared with the conventional piezoresistive pressure sensors, p-type piezoresistors are covered by an n-type shield layer, which is formed by ion implantation. The proposed pressure sensors have been successfully fabricated by bulk micromachining techniques. The impact of electrical field on piezoresistors is studied by simulation. The temperature drift of the pressure sensor has been investigated by both simulation and experimental measurement. Characteristics of developed pressure sensors are tested from -40 C to 125 C. A sensitivity of 0.022 mV/V/KPa and a maximum non-linearity of 0.085% FS are measured for the fabricated sensor in a pressure range of 1 MPa. The temperature coefficients of resistance of shielded piezoresistors are found to be smaller than those of un-shielded ones. It is demonstrated that the shield layer is able to reduce the drift caused by electrical field and ambient temperature variation.

Polyphenols are the most common organic compounds in wine. They improve both the sensory aspects of wine and human health by activating antioxidant systems. Therefore, there is a great need for a simple, fast and accessible method to determine the polyphenol content of wine. The aim of this study is to characterize polyphenolic compounds in natural wine samples using an electrochemical method and a modified carbon paste electrode with TiO2 nanoparticles. This work is motivated by the promising improvement of the sensing properties of a TiO2 nanoparticle-modified carbon paste electrode observed in the electrooxidation of different polyphenols. Since the voltammetric response of wine is largely irreversible, another motivation was the possibility of improving the processing of voltammograms to obtain data indicative of wine polyphenols, based on the approach described in the seminal work by Espinoza et al. The modified electrode studied provides an improved and reproducible voltammetric response of gallic acid in wine samples and provides a good basis for further development of an integrated sensor/data system with the possibility of wider application for the quantification of gallic acid as a flavor and visually relevant parameter in winemaking.

The influence of short term water absorption on the mechanical properties of halloysite nanotubes-multi layer graphene reinforced polyester hybrid nanocomposites has been investigated. The addition of nano-fillers significantly increased the flexural strength; tensile strength and impact strength in dry and wet conditions. After short term water exposure; the maximum microhardness; tensile; flexural and impact toughness values were observed at 0.1 wt% MLG. The microhardness increased up to 50.3%; tensile strength increased up to 40% and flexural strength increased up to 44%. Compared to dry samples; the fracture toughness and surface roughness of all types of produced nanocomposites were increased that may be attributed to plasticization effect. Scanning electron microscopy revealed that the main failure mechanism is caused by the weakening of nano-filler-matrix interface induced by water absorption. It was further observed that synergistic effects were not effective at concentration of 0.1 wt% to produce considerable improvement in mechanical properties of produced hybrid nanocomposites.

This paper proposed a three-layer distributed simulation network architecture: 1. Distributed virtual simulation network, 2. Perception and control sub-network, and 3. Collaborative communication service network. This simulation architecture runs on a distributed platform. The platform can provide a unique virtual scenario and several simulation services to verify the individual robot system's basic perception, control, and planning algorithms and the distributed collaborative algorithms of heterogeneous multi-robot systems. Furthermore, we designed a simulation experiment scenario for classical heterogeneous robot systems such as unmanned aerial vehicles (UAVs) and unmanned ground vehicles (UGVs). At last, We gave a rough estimation model of the bandwidth.

In this paper, carbon nanotubes modified screen-printed electrode (CNTs/SPE) was prepared and the CNTs/SPE was employed for the electrochemical determination of antioxidant substance Chlorogenic acids (CGAs). A pair of well-defined redox peak of CGA was observed at the CNTs/SPE in 0.10 mol∙L^-1 acetic acid-sodium acetate buffer (pH 6.2) and electrode process is adsorption-controlled. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) method for the determination of CGA were proposed based on the CNTs/SPE. Under the optimal conditions, the proposed method exhibited linear ranges from 4.73×10^-7 to 4.45×10^-5 mol∙L^-1, the linear regression equation was Ipa(µA) = 4.1993 C (mol∙L^-1)+1.1039 (r = 0.9976) and the detection limit for CGA could reach 3.25×10^-6 mol∙L^-1. The recovery of matrine was 94.74~106.65% (RSD = 2.92%) in coffe beans. The proposed method is quick, sensitive, reliable, and can be used for the determination of CGA.

From the theory of relativistic chemical kinetics [M. W. Baig, Int. J. Mod. Phys. B 31, 1750177 (2017)] relativistic thermodynamics and kinetics for electrode processes have been developed to explain time dilation for electrode processes. For a moving observer moving at fractions of the speed of light, cell potential is observed to decrease. This results in the slower oxidation and reduction of ions at the respective electrodes. The newly formulated Lorentz transformation of the electrode and cell potential is explained in terms of generation of spin 2-boson “gravitons” from fusion of spin-1 boson “virtual-photons” mediating electrostatic force of attraction between ions and electrodes. It is postulated that birth of spin 2-boson i.e. gravitons is followed by their eventual escape in any of higher 4+n dimensions. To demonstrate the effectiveness of the present theory, the Daniel cell is considered as a numerical example.

The main purpose of this work was to tests of form and size of fatigue wear of the top layer of oil gear pump wheel (3PW-BPF-24). The object of tests was operated during a determined number of hours at strictly controlled operational and environmental parameters. A microscope of focal differentiation by Alicona InfiniteFocus G4 (with Focus-Variation optical measuring technology) was used for an identification, measurement and description of noticed superficial defects, which resulted from the fatigue process of the top layer and an earlier thermochemical treatment. The work was finished with an analysis of obtained results (based on the analysis of 3D scans) and conclusions concerning about optimization of the thermal treatment. Taking into consideration the presented results (suggestions) in the technology of improving strength properties of gear wheels (of this type oil pumps) may render it possible to obtain an appropriate fatigue endurance of the top layer, i.e. a minimization of observed superficial defects.

Along with the rapid development of technology and industry, the need for energy storage has become fundamental. One promising energy storage devices is the supercapacitor. Several type supercapacitors are available, one of which is the electrical double-layer capacitor made from carbon graphite and multiwalled carbon nanotubes (MWCNTs). In this study, we combined these two materials into a working electrode in a three-electrode system. In the morphological analysis using scanning electron microscope, transmission electron microscope, and X-ray diffraction, the two materials were found to have formed a composite on the surface. In the electrochemical analysis, two types of testing were conducted using cyclic voltammetry and electrochemical impedance spectroscopy. Electrochemical analysis was carried out on five electrolyte concentrations of Na2SO4 from 1 to 6 M. The capacitance produced at concentrations of 1, 2, 3, 4, and 5 M were 34.395, 35.808, 46.284, 49.502, and 76.815 F/g, respectively. At an electrolyte concentration of 5 M Na2SO4, an energy density of 27.312 Wh/Kg and a power density of 343.786 W/Kg were produced. Meanwhile on concentration of 6 M, the surface of the electrode was damaged.

Electrode degradation in continuous resistance spot welding process of BH 220 steel was evaluated by electrode life test, and weldability tests were conducted by geometry features measurement, mechanical property analysis, and electrode diameter measurement with 88 or 176 weld intervals. The analysis of weld geometry shows that the HAZ width, nugget diameter, and nugget area tend to decrease rapidly, while the nugget height tends to firstly increase with the weld repetitions till the welding heat input becomes too small to form the valid nugget. The peak load shows a rapid downward trend, while failure energy and maximum displacement slightly increase till the 176th weld and then decrease. The cavities and pores in the nugget mainly appear after the 176th spot weld. The electrode diameter increases during welding. The reason for the increase in electrode diameter may be that the contact area between the electrode and BH 220 steel sheets becomes smaller in the welding process, which causes the continuous sticking phenomenon between the electrode and the BH 220 steel sheets. In the absence of alloying, the edge of the electrode is geometrically deformed, while Cu-Zn-Fe alloying occurs in the area in contact with the BH 220 steel sheet.

Electrochemical energy conversion and storage is key for the use of regenerative energies at large scale. A thorough understanding of the individual components, such as the ion conducting membrane and the electrode layers, can be obtained with scattering techniques on atomit to molecular length scales. The largely heterogeneous electrode layers of High-Temperature Polymer Electrolyte Fuel Cells are studied in this work with small- and wide-angle neutron scattering at the same time with the iMATERIA diffractometer at the spallation neutron source at J-PARC, opening a view on structural properties on atomic to mesoscopic length scales.

Glucose-sensitive films were prepared by the layer-by-layer (LbL) deposition of poly(ethyleneimine) (H-PEI) solution and DNA solution (containing glucose oxidase (GOx)). H-PEI/DNA+GOx multilayer films were constructed using electrostatic interactions. The (H-PEI/DNA+GOx)5 film was then partially decomposed by hydrogen peroxide (H2O2). The mechanism for the decomposition of the LbL film was considered to involve a more reactive oxygen species (ROS) that was formed by the reaction of hemin and H2O2, which then caused nonspecific DNA cleavage. GOx present in the LbL films reacts with glucose to generate hydrogen peroxide. Therefore, decomposition of the H-PEI/DNA+GOx)5 film was observed when the thin film was immersed in a glucose solution. A (H-PEI/DNA+GOx)5 film exposed to a glucose solution for periods of 24, 48 72, and 96 h indicated decomposition of the film increased with the time. The rate of LbL film decomposition increased with the glucose concentration. At pH and ionic strength close to physiological conditions, it was possible to slowly decompose the LbL film at a sub-millimolar glucose concentration.

Crystalline silver thin layers were obtained by high-energy pulsed laser ablation without heating of the deposition substrate. The fluid Plateau-Rayleigh (PRI), Rayleigh – Taylor (RTI) and Richtmyer – Meshkov (RMI) instabilities, as well as crown splash induced during pulsed laser deposition (PLD) in high energy regime, resulting in ring and pearl shaped structures, offer the benefit of increased sorption surface. These morphological structures obtained for the silver thin layers make them of interest for catalytic applications. The study presented with this work addresses both the fundamental and applied issues on the morphological structures obtained for the silver thin layer and their catalytic function in organic processes. In this sense, the catalytic action of the thin silver layer was highlighted by modifications of the Reactive Blue 21 dye (C.I.) in aqueous solution with sodium bicarbonate. Specific investigations and analyzes were carried out by electron microscopy and elemental analysis (SEM-EDX), atomic force microscopy (AFM) and profilometry, mass spectrometry, ablation plasma diagnosis, diffractograms (XRD), as well as IR spectroscopy (FTIR). In addition to the experimental investigation and analyzes, simulation of the ionization energy threshold was conducted in COMSOL for complementary evaluation on the involved processes and phenomena.

Electrospun nanofiber-supported thin film composite membranes are among the most promising membranes for seawater desalination via forward osmosis. In this study, a high-performance electrospun polyvinylidenefluoride (PVDF) nanofiber-supported TFC membrane was successfully fabricated after molecular layer-by-layer polyelectrolyte deposition. Negatively-charged electrospun polyacrylic acid (PAA) nanofibers were deposited on electrospun PVDF nanofibers to form a support layer consisted of PVDF and PAA nanofibers. This resulted to a more hydrophilic support compared to the plain PVDF nanofiber support. The PVDF-PAA nanofiber support then underwent a layer-by-layer deposition of polyethylenimine (PEI) and PAA to form a polyelectrolyte layer on the nanofiber surface prior to interfacial polymerization, which forms the selective polyamide layer of TFC membranes. The resultant PVDF-LbL TFC membrane exhibited enhanced hydrophilicity and porosity, without sacrificing mechanical strength. As a result, it showed high pure water permeability and low structural parameter values of 4.12 Lm⁻²h⁻¹bar⁻¹ and 221 µm, respectively, significantly better compared to commercial FO membrane. Layer-by-layer deposition of polyelectrolyte is therefore a useful and practical modification method for fabrication of high performance nanofiber-supported TFC membrane.

The novelty of this study consists in: i) synthesis and characterization of electrode materials recycled from a spent car battery and doped with MnO2 and CuO by the analysis of X-ray diffraction (XRD), Infrared (IR) and Electron Paramagnetic Resonance (EPR) data and ii) the investigation of electrochemical properties of prepared materials in view of new applications as electrode materials for battery. Electron Paramagnetic Resonance (EPR) data indicate that the intensity of the resonance line corresponding to the Cu+2 ion was modified with the increase of the dopant content. The analysis of X-ray Absorption Spectroscopy (XAS) data indicates that by increasing the dopant content there is a process of ordering the oxygen atoms around the lead similar to the PbO2 theoretical model. The electrochemical performances of the recycled and manganese-copper-doped materials are optimized for applications as new anodic electrode for the car battery.

Precise monitoring of different environmental parameters and contaminations during food processing and storage is a key factor for maintaining its safety and nutritional value. Thus, developing reliable, efficient, cost-effective sensor devices for these purposes is of utmost importance. In this paper, we show that Poly-(diallyl-dimethylammonium chloride)/reduced Graphene oxide (PDAC/rGO) films produced by a simple Layer-by-Layer deposition can be effectively used to monitor temperature, relative humidity and the presence of volatile organic compounds as indicators for spoilage odors. At the same time, they show potential for electrochemical detection of organophosphate pesticide dimethoate. By monitoring the resistance/impedance changes during temperature and relative humidity variations or upon the exposure of PDAC/rGO films to methanol, good linear responses were obtained in the temperature range of 10-100 °C, 15-95 % relative humidity, and 35 ppm - 55 ppm of methanol. Moreover, linearity in the electrochemical detection of dimethoate is shown for the concentrations in the order of 102 µmol dm−3. The analytical response to different external stimuli and analytes depends on the number of layers deposited, affecting sensors’ sensitivity, response and recovery time, and long-term stability. The presented results could serve as a starting point for developing advanced multimodal sensor devices and sensor arrays with high potential for analytical applications in food safety and quality monitoring.

A nanostructured electrochemical bi-sensor system for analysis of milks has been developed using the Layer by Layer technique. The non-enzymatic sensor [CHI+IL/CuPcS]2, is a layered material containing a negative film of the anionic sulfonated copper phthalocyanine (CuPcS) acting as electrocatalytic material, and a cationic layer containing a mixture of an ionic liquid (IL) (1-butyl-3-methylimidazolium tetrafluoroborate) that enhances the conductivity and chitosan (CHI) that facilitates the enzyme immobilization. The biosensor ([CHI+IL/CuPcS]2-GAO) results from the immobilization of galactose oxidase on the top of the LbL layers. FTIR, UV-vis and AFM have confirmed the proposed structure and cyclic voltammetry has demonstrated the amplification caused by the combination of materials in the film. Sensors have been combined to form an electronic tongue for milk analysis. Principal Component Analysis has revealed the ability of the sensor system to discriminate between milk samples with different lactose content. Using PLS-1 calibration models, correlations have been found between the voltammetric signals and chemical parameters measured by classical methods. PLS-1 models provide excellent correlations with lactose content. Additional information about other components such as fats, proteins and acidity can also be obtained. The method developed is simple and the short response time permits its use in assaying milk samples on-line.

The copper deposition on the platinum and palladium nanoelectrode has been studied using cyclic voltammetry. The use of nanoelectrode platinum and palladium are defined in the study of heavy metals. The noble nanoelectrode of metal has a typical silicone processing structure. In comparison to the nanoelectrodes, the geometry of the electrode series is complex and balanced. Nanoelectrodes of platinum are found effective in detecting heavy metal. There was regular analysis of the use of the sensors. The identification constraints down to the ng /L level was accomplished by refined electrode geometry and the stripping procedures. The process was used for the study of water sample determination. Another heavy metal ion attack voltammetric reaction was studied. The SEM picture clearly observed and characterized the nanoparticle electrode by X-ray diffraction and cyclic voltammetry.

A new sulbatamol sulphate SBS membrane electrode was prepared that utilizing for its determination ; depend on the forming of the association complex ion of sulbatamol sulphate by the phosphotungstate counter anion deposed in poly vinyl chloride PVC polymer, by use a (Di-n- Octyl Phenyl Phthalate)(Dopp) as the plastizier substance, in membrane.The features properties as well as the behavior of it .The new electrode have been elaborated. The concentrations of medicine by utillizing This sensor show a fast, stable, near-Nernstian response in the range (1x10^-1-1x10^-6) mol/ L were determined with correlation coefficient of about (r = 0.9991) and with of a relative standard about 0.416 additionally deviation relative standard error of 1.710 %.^pot The nernast linearity slop was founded and it is equal to 28.9 mV/decade and the detection limit was 4.1 x 10^-6 mol/ L.The electrode selectivity coefficient K_i,j was calculated, in the existence of several interferences cations with confirmed medicine solutions. It was found the pH range response is in the range of (3 -7), with the response time of (30 – 116) sec. for various concentrations at room temperture , the lifetime for electrode was found to be more than 21 days. The electrode was successfully used for potentiometric limitation of sulbatamol sulphate in several pharmaceutical drugs by using direct potentiometry.

The layer-by-layer (LBL) fabrication method allows for controlled microstructure morphology and vertical component distribution, and also offers a reproducible and efficient technique for fabricating large-scale organic solar cells (OSCs). In this study, polymer D18 and PYIT-OD are employed to fabricate all-polymer solar cells (all-PSCs) using the LBL method. Morphological studies reveal that the use of additives optimizes the microstructure of the active layer, enhancing the crystallinity and charge transport capability. The optimized device with 2% CN additive significantly reduces bimolecular recombination and trap-assisted recombination. All-PSCs fabricated by the LBL method based on D18/PYIT-OD deliver a power conversion efficiency (PCE) of 15.07%. Our study demonstrates the great potential of additive engineering via LBL fabrication method in regulating microstructure of active layers, suppressing charge recombination, and enhancing the photovoltaic performance of devices.

This paper intends to discuss SSLs, how they work, their advantages and drawbacks. It will end with the author’s thoughts on the efficacy of the system and whether it is a viable solution for the majority of network security problems or if those drawbacks prevent that.

Molybdenum oxides is well-known electro-catalysts in fuel cells systems, they are usually used as anodic materials for the oxidation of low molecular weight alcohols. The utilization of Mo as catalysts in the pharmaceutical analysis is not common yet. In this study, bare glassy carbon electrodes were modified by the oxides by means of electrochemical deposition and the modified electrodes were used as catalysts for the electrochemical oxidation of hydrochlorothiazide (HCT). Well-resolved anodic peaks were reported for the analyzed pharmaceuticals when the Mo/GCE was utilized for the analysis of HCT. Analytical performance of the modified electrodes was evaluated based on the following statistical parameters; linearity ranges, correlation coefficients, limits of detection and quantitation, and recovery values. The prepared electrodes were used for the determination of the active ingredients in their pharmaceutical formulations and the reported activity was correlated to influence of the utilized pH on both structures of the used electrodes and the detected analytes.

A temperature-modulated pyroelectricity measurement system for a small single crystal is developed and applied to standard sample measurements performed on a thin single crystal of lithium niobate. The modulation measurement is based on the AC technique, in which the temperature of the sample is periodically oscillated, and the synchronized pyroelectric signal is extracted using a lock-in amplifier. Temperature modulation is applied by irradiating periodic light on the sample placed in the heat exchange gas. To apply this technique to the transparent reference sample, a commercially available black resin is coated on the sample’s surface to absorb the light energy and transmits it to the specimen. The experimental results are analyzed using a two-layer heat transfer model to verify the effect of the light-absorbing layer as well as the non-contact temperature modulation system.

Recently, the difficulties in recycling and environmental pollution caused by metal-based electrode materials have limited the further development of batteries. Therefore, biomass carbon materials, with their environmental friendliness and stable performance, are the key to solving this problem. Many advances have been achieved by researchers for the application of biomass porous carbon materials in batteries. Nevertheless, the same biomass carbon materials in batteries face problems such as low utilization, low yield, and a cumbersome preparation process. This paper thus aims to summarize the recent progress of biomass carbon materials in the field of batteries and provide a detailed description of the battery performance of biomass carbon materials from three perspectives: synthesis, structure and application of carbon materials. We believe that biomass carbon composites are in line with future development and have a broad application prospect. Finally, we will give our in-depth prospect on developing biomass carbon materials.

Pollution by heavy metals is one of the most severe environmental issues that threaten global sustainability. This review presents a recent advance in electrochemical sensors for heavy metal detection Rotating Disk Platinum Electrode are discussed. This study on the production of a modern natural water electrochemical antimony (II) and cupper (II) test include the use of platinum electrode. Antimony and cupper were pre-concentrated on the modified electrode surface and adsorbed to the surface, oxidizing at E = 540 mV and E = 85 mV, respectively. After 20 min of accumulation, time the best-defined anodic peak was obtained of surface. The precision was tested by carrying out chronoamperometric measurements at a concentration of Sb⁺² and Cu⁺² 8.5x10^-8 M and 9.5x10^-7 M, respectively.

The present Feature Paper highlights the application of bacterial surface (S-) layer proteins as versatile components for the fabrication of biosensors. One technologically relevant feature of S‑layer proteins is their ability to self-assemble on many surfaces and interfaces to form a crystalline 2D protein lattice. The S-layer lattice on the surface of a biosensor becomes part of the interface architecture, linking the bioreceptor to the transducer interface, which may cause signal amplification. The S-layer lattice as ultrathin, highly porous structure with functional groups in a well-defined special distribution and orientation and an overall anti-fouling characteristics can significantly raise the limit in terms of variety and ease of bioreceptor immobilization, compactness of bioreceptor molecule arrangement, sensitivity, specificity, and detection limit for many types of biosensors. The present paper discusses and summarizes examples for the successful implementation of S-layer lattices on biosensor surfaces in order to give a comprehensive overview on the application potential of these bioinspired S-layer protein-based biosensors.

Here, we investigate the actuation dynamics of a micro device with different intervening liquids between the actuating components under the influence of Casimir and dissipative hydrodynamic forces. This is enabled via phase space portraits, which demonstrate that by increasing the dielectric response of the intervening layer the device may not come into stiction due to the decreasing in magnitude Casmir force. Moreover, it is feasible to expand area of motion using intervening liquids with lower dynamic viscosity or increasing the slip length of the intervening fluid. Finally, under the influence of an external driven force, which is the realistic case for possible applications, the system can reach stable oscillation at larger separations with an amplitude higher for the liquid that lead to lower Casimir and hydrodynamic forces.

Electrophysiological mapping (EM) using acute electrode probes is a common procedure performed during functional neurosurgery. Due to their constructive specificities, the EM probes are lagging in innovative enhancements. This work addressed complementing a clinically employed EM probe with carbonic and circumferentially segmented macrocontacts that are operable both for neurophysiological sensing ("recording") of local field potentials (LFP), and for test stimulation. The paper illustrates in-depth the development, that is based on direct writing of functional materials. The unconventional fabrication processes were optimized on planar geometry and then transferred to the cylindrically thin probe body. We report and discuss on the constructive concept and architecture of the probe, characteristics of the electrochemical interface deduced from voltammetry and chronopotentiometry, and the results of in vitro and in vivo recording and pulse stimulation tests. Two and three directional macrocontacts were added on probes having shanks of 550 and 770 m diameters and 10-23 cm lengths. The graphitic material presents a ~2.7 V-wide, almost symmetric water electrolysis window, and an ultra-capacitive charge transfer. When tested with 150 s biphasic current pulses, the interfacial polarization stayed safely away from the water window for pulse amplitudes up to 9 mA (135 C/cm2). The in vivo experiments on adult rat models confirmed the high-quality sensing of LFPs. Additionally, the in vivo-prevailing increase of the electrode impedance and overpotential are discussed and modeled by an ionic mobility-reducing spongiform structure; this restricted diffusion model gives new applicative insight into the in vivo-uprisen stimulation overpotential.

One of the significant challenges today in the brain-machine interface using invasive methods is the stability of the chronic record. In recent years, polymer-based electrodes have gained notoriety for achieving mechanical strength values close to that of brain tissue, promoting a lower immune response to the implant. In this work, we fabricated fully polymeric electrodes based on PEDOT:PSS for neural recording in Wistar rats. We characterized the electrical properties and both in-vitro and in-vivo functionality of the electrodes. Also, we employed histological processing and microscopical visualization to evaluate tecidual immune response in 7, 14, and 21 days post-implant days. Electrodes with 400-micrometer channels showed a 12dB signal-to-noise ratio. Local field potentials were characterized under two conditions: anesthetized and free-moving. There was a proliferation of microglia to the tissue-electrode interface in the first days, with a decrease after 14 days. Astrocytes also migrated to the interface, but there was no continuous recruitment of these cells in the tissue, showing inflammatory stability at 21 days. The signal was not affected by this inflammatory action, demonstrating that fully polymeric electrodes can be an alternative to prolong the valuable time of neural recordings.

In this study the processes taking place on the surfaces of nanostructurized Cu/CuO and Cu/CuO/Pd electrodes at different potential, $E$, values in the solutions of 0.1 M KOH in H$_2$O and D$_2$O (heavy water) were probed by the surface enhanced Raman spectroscopy (SERS) and analysis of electrochemical reactions occurring under experimental conditions is presented. Bands of the SERS spectra of Cu/CuO/Pd electrode observed in the range of $E$ values from +0.3~V to 0 V~(SHE) at 1328 - 1569~cm$^{-1}$ are consistent with the existence of species which are adsorbed or weakly bound to the surface with the energy of interaction close to 15 - 21~kJ mol$^{-1}$. These bands can be attributed to the ad(ab)sorbed (H$_3$O$^+$)$\rm{_{ad}}$, (H$_2^+$)$\rm{_{ab}}$ and (H$_2^+$)$\rm{_{ad}}$ ions as intermediates in reversible HER/HOR processes taking place on Cu/CuO/Pd electrode. There was no isotopic effect observed; this is consistent with a dipole nature of electron-ion pair formation of adsorbed (H$_3$O$^+$)$\rm{_{ad}}$ and (H$_2^+$)$\rm{_{ad}}$ or (D$_3$O$^+$)$\rm{_{ad}}$ and (D$_2^+$)$\rm{_{ad}}$. In accordance with literature data SERS bands at 125-146~cm$^{-1}$ and $\sim 520-565$~cm$^{-1}$ were assigned to Cu(I) and Cu(II) oxygen species. These findings corroborate the mechanism of cascading reduction of water.

This review provides informations and details for the fabrication of biosensors that are composed from lipid membranes and have been utilized and applied to rapidly detect food toxic compounds, environmental pollutants and analytes of clinical interest. Biosensors based on polymeric lipid membranes have been used to rapidly detect a wide range of these analytes and offer several advantages such as fast response, high sensitivity and selectivity, can be portable for in the field applications, and small size. A description of the construction of these devices and their applications for the rapid detection of food toxic substance, environmental pollutants and analytes of clinical interest is provided in this review.

Due to its time effective, joint friendly and highly customizable character whole-body-electromyostimulation (WB-EMS) is regarded as a feasible solution for a large variety of training issues particularly in the area of non-athletic application. To identify gaps in research and summarize prevalent evidence we conducted an evidence map on outcomes addressed by WB-EMS trials in middle-aged to older, non-athletic adults. Based on a comprehensive systematic search in five databases and two study registers according to PRISMA, 54 projects published in 80 articles were included. More than 90% of the studies reported outcomes related to the physical fitness or function domain. Body composition parameters were addressed by two thirds of the projects. Health-related outcomes addressed by WB-EMS included cancer/neoplasm (n=7), endocrine regulation (n=8), glucose metabolism (15), nervous system diseases (n=2), cardiovascular system diseases (n=22), non-specific chronic low back pain (n=4), osteopenia (n=5) and diseases of the renal system (n=12). Outcomes related to inflammation were addressed 18 times. Of importance, no studies reported clinically relevant adverse effects related to the WB-EMS intervention. In summary, while considerable evidence on outcomes related to fitness/function and body composition is prevalent, evidence gaps of WB-EMS research were particular evident for diseases of the nervous and cerebrovascular system.

The development of smart negative electrode materials with high capacitance for use in supercapacitors remains challenging. Although there have been several types of electrode materials with high capacitance used in energy storage, carbon-based materials are the most reliable electrodes due to their high conductivity, high power density and excellent stability. The most common complaint about general carbon materials is that these as-formed electrode materials can hardly ever be used as free-standing electrodes. Free-standing carbon-based electrodes are in high demand and are a passionate topic of energy storage research. Electrospun nanofibers are a potential candidate to fill this gap. However, the as-spun carbon nanofibers (ECNFs) have low capacitance and energy density on their own. To this end, several attempts have been made to improve these characteristics. In this review, we introduce negative electrode materials that have been developed. Moreover, this review places special attention to the advances of electrospun nanofiber-based negative electrode materials and their limitations. Based on the above information, we put forth a future perspective on how these limitations can be overcome to meet the demands of next-generation smart devices.

Non-standard diesel blends can be harmful to the environment and human health. In this context, a simple analytical method to estimate the biodiesel mixture ratio in diesel was developed based on the impedance spectroscopy (IS) associated with the interdigitated sensors. In this article, four different interdigitated sensors, variable comb spacing (G), were simulated using the COMSOL Multiphysics software. Based on finite element simulations, four interdigitated electrode architectures by manufactured and evaluated. According to the X-ray powder diffraction technique, the deposition of the conductive layer (Au°) over the surface of the dielectric substrate (SiO2) did not alter its phase composition. In the analysis of AFM and SEM, it was possible to observe irregular edges on the electrodes, possibly related to thin layers' manufacturing process and mechanical stability. Another characteristic observed in the AFM images was the height of the step of the gold layer of the sensor. Several cross-sections were obtained, and the mean step value is 225.71 ± 0.0032 nm. Although there are differences in the roughness, the whole sensor has nanometric roughness. Based on the finite element method simulation performed, it can be assumed that the geometric parameters more suitable for the manufacturing of the electrode are: W = 20 µm, L = 1000 µm, G = 50 µm e N = 40 digits. The electrical characterization performed by impedance spectroscopy showed that we could differentiate between biodiesel and diesel fuels and their pseudo-binary mixtures in the low-frequency region.

The aims of this work were to examine the new electrode, based on polymer bacteria modified aluminum electrode for simultaneous production of electricity and degradation of phenol. This electrode is based aluminum modified by bacteria inserted in the polymer matrix, developed in situ on the surface. This electrode, designated subsequently by bacteria-polymer-aluminum, Showed stable response and was characterized with voltametric methods, as cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The experimental results revealed that the prepared electrode could be a feasible for degradation of hazardous phenol pollutants. The sensor was successfully applied to the determination of phenol in a real sample with satisfactory results.

OSI model used to be common network model for years. In the case of ad hoc networks with dynamic topology and difficult radio communications conditions, gradual departure is happening from the classical kind of OSI network model with a clear delineation of layers (physical, channel, network, transport, application) to the cross-layer approach. The layers of the network model in ad hoc networks strongly influence each other. Thus, the cross-layer approach can improve the performance of an ad hoc network by jointly developing protocols using interaction and collaborative optimisation of multiple layers. The existing cross-layer methods classification is too complicated, because it’s based on the whole manifold of network model layers combinations, regardless their importance. In this work, we review ad hoc networks cross-layer methods, propose the new useful classification of cross-layer methods, and show future research directions in ad hoc networks cross-layer methods development. The proposed classification can help to simplify the goal-oriented cross-layer protocol development.

A 9,10-phenanthrenequinone (PQ) was electrochemically polymerized on a graphite rod electrode using potential cycling. The electrode modified by poly-9,10-phenanthrenequinone (poly-PQ) was studied by means of cyclic voltammetry, electrochemical impedance spectroscopy, atomic force microscopy and scanning electron microscopy. The poly-PQ shows variations in growth pattern depending on the number of potential cycles for the initiation of polymerization. Formed poly-PQ layer demonstrates good electric conductivity, great electrochemical capacitance and unique oxidation/reduction properties, which are suitable for broad technological applications, including applicability in biosensors, supercapacitors, and in some other electrochemical systems.

In this work, we studies the principle of ground electrode current field through ground communication technology, signal design, and optimal working mode of excitation source, so as to adapt the working mode, working frequency, and transmission medium condition of signal transmission. Through waveform design, energy is concentrated in the main conduction direction, which is beneficial for signal filtering at the receiving end and achieving high reliability data transmission; On this basis, on-site environmental testing was conducted to verify the detection and recognition technology of weak signals. Signal design and detection recognition are a very important part of the grounding electrode current field through ground communication technology. The grounding electrode current field through ground communication technology is mainly applied to solve the problem of communication between rescue personnel and trapped personnel before and during tunnel engineering collapse and rescue.

Carburizing of stainless steels at low temperatures (below 500°C) develops a high content carbon layer, known for its high hardness. X-ray Diffraction investigation indicates that carburization treatment does not impact the structure of substrate; however, introduced carbon causes expansion in the carburized layer through the increase in d-spacing. Characterization of carbon concentration and hardness profiles indicate that carbon content gradually decreases while moving further into the substrate; and the origin of the increased hardness of the expanded layer arises from the super-saturated carbon content, following the solid solution strengthening theory. An area that is not well understood is in regard to the carburized layer’s relation to the substrate and the significance in their differences. Using two grades of stainless steel, AISI 316L and PH 17-4, it was observed that the carburized layer is not a separate layer, but a higher carbon content version of the substrate,

An effective approach to fabricate large-scale of conducting polyaniline (PANI) by an in situ anodic electrochemical polymerization on the nickel foam, which coated by a novel aryl diazonium salt (ADS)-functionalized graphene (ADS-G). In present work, ADS-G was used as a high surface area support material for electrochemical polymerization of PANI. Electrochemical performances of the ADS-G/PANI composites exhibited better suitability as supercapacitor electrode materials than that of the PANI. The ADS-G/PANI composites achieved the specific capacitance of 528 F g-1, which was higher than that of PANI (266 F g-1) due to the excellent electrode-electrolyte interaction and synergistic effect of electrical conductivity between ADS-G and PANI in the composites. These findings suggested that the ADS-G/PANI composites were a suitable composite for the potential supercapacitor applications.

In this work we successfully prepared a modified cobalt oxide (Co3O4) carbon paste electrode to detect Levofloxacin (LEV). By synthesizing Co3O4 nanoparticles through the chemical coprecipitation method, the electrochemical properties of the electrode and LEV were thoroughly investigated using CV, SWV, EIS, while material properties were scrutinized using ICP-OES, TEM, SEM, and XRD. The results showed that the prepared electrode displayed a better electrocatalytic response than the bare carbon paste electrode. After optimizing SWV, the electrode exhibited a wide linear working range from 1 to 85 μM at pH 5 of BRBS as the supporting electrolyte. The selectivity of the proposed method was satisfactory, with good repeatability and reproducibility, strongly suggesting a potential application for determining LEV in real samples, particularly in pharmaceutical formulations. The practicality of the approach was demonstrated through good recoveries, and the morphology of the materials was found to be closely related to other parameters, indicating that the developed method can provide a cost-effective, rapid, selective, and sensitive means for LEV monitoring. Overall, this project has made significant progress towards developing a reliable method for detecting LEV and has opened up new opportunities for future research in this field.

In this study, the preparation of the composite 3% Au/graphite-C3N4 (3% Au/g-C3N4) sensing material was prepared by doping 3% Au onto the surface of graphitic carbonitride (C3N4) for detection pimobendan. By the way of sensing materials characterization, the X-ray diffraction analysis (XRD) and transmission electron Microscope (TEM) were performed. The cyclic voltammetry (CV) was used to measure the concentration and redox properties of pimobendan. It can be seen that when the voltage value is 0.05 V, and a reduction peak was appeared and the pimobendan concentration (0 to 55 μM) has a relationship with the reduction current value. At low concentrations of pimobendan concentration from 0.0 to 0.8 μM, the linearity R2 = 0.9642 with a detection limit of 0.28 μM. A possible pimobendan sensing mechanism on 3% Au/g-C3N4 was proposed.

The present review article concludes with three different types of materials recently used to enhance the efficiency of supercapacitors. The first type involves carbon-based materials for storage and supercapacitor applications. The carbon materials could be obtained naturally and synthesized manually based on the needs. The second type discusses the recent advances in metal oxide materials for high-performance supercapacitors. The metal oxide materials involve in different types of attachment through the bi-tri metallic bonding, which enhances the specific capacitance. The third type involves recently advanced materials for high energy and power density application. The power and energy density of the materials is enhanced by the surface modification of the materials. In recent days, the MXene and Nano-composite materials seems to be an appropriate material to increase the power and energy density of the device.

Population growth and increasing global demand for freshwater have raised a serious challenge for the depleting sources of freshwater in the 21st century. Desalination technologies can be a reliable technique for providing freshwater. Capacitive deionization is one of the innovative desalination methods that has received increasing interest. Flow-electrode capacitive deionization (FCDI) (a new architecture of capacitive deionization) is one of the efficient, cost-effective, and environmentally-friendly desalination methods for freshwater production. In this experimental research, the performance of an FCDI system was investigated and the influence of important parameters such as flow rate of flow-electrodes, electrolyte salt concentration of flow-electrodes, and initial feed water concentration will be assessed on the efficiency of desalination operation. In this study, the flow-electrodes operated in short-circuited closed-cycle operation (SCC) mode, and also the feed water operated similarly to the flow-electrodes in closed-cycle. Moreover, in all the experiments, the salt adsorption capacity (SAC) and salt removal efficiency (SRE) was calculated. Herein, by optimizing the above mentioned parameters, the salt removal efficiency of 83% and a SAC value of 29.12 mg/g dry carbon were achieved in 5 hours.

Laser reduced graphene oxide (LRGO) on a PET substrate was prepared in one-step to obtain the LRGO grid electrode for sensitive carbaryl determination. The grid form results in a grid distribution of different electrochemically active zones affecting the electroactive substance diffusion towards to the electrode surface and increasing the electrochemical sensitivity for carbaryl determination. Carbaryl is electrochemically irreversibly oxidized by the secondary amine moiety of the molecule with the loss of one proton and one electron in the pH range from 5 to 7 by LSV on the LRGO grid electrode with a scan rate of 300 mV/s. Some interference of the juice matrix molecules did not significantly affect the LSV oxidation current of carbaryl on the LRGO grid electrode after adsorptive accumulation without applied potential. The LRGO grid electrode can be used for LSV determination of carbaryl in fruit juices in the concentration range from 0.25 to 128 mg/L with LOD of 0.1 mg/L by. The fabrication of the LRGO grid electrode opens up possibilities for further inexpensive monitoring of carbaryl in other fruit juices and fruits.

We have proposed a data-driven approach for designing mesoscale porous structures of Li-ion battery electrode with three-dimensional virtual structures and machine learning techniques. Over 2,000 artificial 3D structures assuming positive electrode composed of random packed spheres as active material particles are generated, and charge/discharge resistance has been evaluated using simplified Physico-chemical model. In this model, resistance from Li diffusion in active material particles (diffusion resistance), transfer resistance of Li+ in electrolyte (electrolyte resistance) and reaction resistance on the interface between active material and electrolyte are simulated based on mass balance of Li, Ohm’s law in and linearized Butler-Volmer equation, respectively. Using these simulation results, regression models via Artificial Neural Network (ANN) have been created in order to predict charge/discharge resistance from porous structure features. In this study, porosity, active material particle size and volume fraction, pressure in the compaction process, electrolyte conductivity, and binder volume fraction are adopted as features, associated with controllable process parameters for manufacturing battery electrode. As results, the predicted electrode resistance by ANN regression model is good agreement with the simulated values. Furthermore, sensitivity analysis and optimization of the process parameters have been carried out. The proposed data-driven approach could be a solution as a guiding principle for manufacturing battery electrode.

In this work, we focus on investigating electrothermal flow in a rotating electric field (ROT-ETF), with primary attention paid to the horizontal traveling-wave electrothermal (TWET) vortex induced at the center of the electric field. The frequency-dependent flow profiles in the microdevice are analyzed using different heat transfer models. Accordingly, we address in particular the importance of electrode cooling in ROT-ETF as metal electrodes of high thermal conductivity while substrate material of low heat dissipation capability are employed to develop such microfluidic chips. Under this circumstance, cooling of electrode array due to external natural convection on millimeter-scale electrode pads for external wire connection occurs and makes the internal temperature maxima shift from the electrode plane to a bit of distance right above the cross-shaped interelectrode gaps, giving rise to reversal of flow rotation from a typical repulsion-type to attraction-type induction vortex, which is in good accordance with our experimental observations of co-field TWET streaming at frequencies on the order of reciprocal charge relaxation time of the bulk fluid. These results point out a way to make a correct interpretation of out-of-phase electrothermal streaming behavior, which holds great potential for handing high-conductivity analytes in modern microfluidic systems.

The design and engineering of antibacterial materials is key for preventing bacterial adherence and proliferation in biomedical and house-hold instruments. Silver nanoparticles (AgNPs) and chitosan (CHI) are broad-spectrum antibacterial materials with different properties, whose combined application is currently under optimization. This study proposes the formation of antibacterial films with AgNPs embedded in carboxymethylcellulose/chitosan multilayers by the layer-by-layer (LbL) method. The films were deposited onto nanoporous silicon (nPSi), an ideal platform for bioengineering applications, due to its biocompatibility, biodegradability, and bioresorbability. We focus on two alternative multilayer deposition processes: cyclic dip coating (CDC) and cyclic spin coating (CSC). The physicochemical properties of the films were the subject of microscopic, microstructural and surface-interface analyses. The antibacterial activity of each film was investigated against Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) bacteria strains as model microorganisms. According to the findings, CDC technique produced multilayer films with higher antibacterial activity for both bacteria compared to the CSC method. Bacteria adhesion inhibition was observed from only 3 cycles. The developed AgNPs-multilayer composite film offers advantageous antibacterial properties for biomedical applications.

To achieve an acceptable level of security on the web, the Completely Automatic Public Turing test to tell Computer and Human Apart (CAPTCHA) was introduced as a tool to prevent bots from doing destructive actions such as downloading or signing up. Mobile devices have small screens, and therefore, using the common CAPTCHA methods (e.g. text CAPTCHAs) in these devices raises usability issues. To introduce a reliable, secure, and usable CAPTCHA that is suitable for mobile devices, this paper introduces a hand gesture recognition CAPTCHA based on applying Genetic Algorithm (GA) principles on Multi-Layer Perceptron (MLP). The proposed method improves the performance of MLP-based hand gesture recognition. It has been trained and evaluated on 2201 videos of the IPN Hand dataset, and MSE and RMSE benchmarks report the index values of 0.0018 and 0.0424, respectively. Comparison with the related works shows a minimum of 1.79% fewer errors, and experiments produced a sensitivity of 93.42% and accuracy of 92.27% – 10.25% and 6.65% improvement compared to the MLP implementation.

The utilization of dual-potential mode of integrated array (IDA) electrodes and other two-electrode systems has revolutionized electrochemical detection by enabling the simultaneous and independent detection of two species, accompanied by the exhibition of unique characteristics. In contrast to conventional dual-potential electrodes, the rotating ring disk electrodes (RRDE), IDA electrodes demonstrate analogous yet vastly improved performance metrics, characterized by remarkable collection efficiency and sensitivity. Notably, due to the distinctive microscale structure of IDA electrode, the special “feedback” effect makes IDA a unique signal amplifier. In recent decades, the research surrounding IDA electrodes has garnered escalating interest due to their attractive attributes. This review centers its focus on the fabrication and applications of IDA electrodes. In the realm of fabrication, two critical breakthroughs are poised for realization: the achievement of reduced dimensions and the diversification of materials. Established fabrication methods for IDA electrodes encompass photolithography, inkjet printing, and direct laser writing, each affording distinct advantages in terms of size and precision in IDA construction. Predominantly employed materials for IDA electrodes include gold, platinum, and carbon, with the selection of fabrication methods guided by considerations such as material properties, desired dimensions, cost-efficiency, and specific application requisites. Within the domain of applications, IDA electrodes, capitalizing on their distinctive attributes, have found utility in diverse fields. This review summarizes the applications of IDA electrodes based on their fundamental working principles, encompassing redox cycling, resistance modulation, capacitance variations, and more. The potential for further development of this specialized tool to exhibit enhanced properties holds substantial promise.

The inhibition of localised corrosion is known to involve multiple processes taking place over a range of time and length scales that are difficult to study by conventional electrochemical methods. This work demonstrates an approach to probing complex localised electrochemical processes by combining an electrochemically integrated multi-electrode array (also known as wire beam electrode (WBE)), scanning vibrating electrode technique, scanning electrochemical microscopy and surface analytical techniques. Each technique reveals certain aspects of the dynamically changing, multi-scale, inhibitor-microstructure interactions and local chemistry over a heterogeneous AA2024-T3 alloy surface in the presence of an environmentally friendly inhibitor; cerium diphenyl phosphate (Ce(dpp)3).

The DEP force is usually calculated from the object’s point of view using the interaction of the object’s induced dipole moment with the inducing field. Recently, we described the DEP behavior of high- and low-conductive 200-µm 2D spheres in a square 1x1mm chamber with a plane-versus-plane electrode configuration from the system’s point of view. Here we extend our previous considerations to the plane-versus-plane and pointed-versus-pointed electrode configurations. The trajectories of the sphere center and the corresponding DEP forces were calculated from the gradient of the system’s overall energy dissipation for given starting points. The dissipation’s dependence on the sphere’s position in the chamber is described by the numerical “conductance field”, which is the DC equivalent of the capacitive charge-work field. While the plane-versus-plane electrode configuration is field-gradient free without an object, the presence of the highly or low-conductive spheres generates structures in the conductance fields, which result in very similar DEP trajectories. For both electrode configurations, the model describes trajectories with multiple endpoints, watersheds, and saddle points, very high attractive and repulsive forces in front of pointed electrodes, and the effect of mirror charges. Because the model accounts for inhomogeneous polarization within the objects, the approach allows the modeling of the complicated interplay of attractive and repulsive forces near electrode surfaces and chamber edges. Non-reversible DEP forces or asymmetric magnitudes for the highly and low-conductive spheres in large areas of the chamber indicate the presence of higher-order moments, mirror charges, etc.

During HVDC earth return operation systems, a high magnitude current will be injected into soil through earth electrode, the potential on the surface would change widely and produce unfavorable effects on the AC systems around. This paper presents an effective finite element method (FEM) coupling electric field with thermal field to evaluate the electrical field induced by the injected DC current. Firstly, owe to the characteristic of FEM, this method can consider arbitrary soil and earth electrode structure. Secondly, by setting the electrical and thermal parameters of soil as a function of temperature at the same time, the dynamic coupling process of electric field and thermal field is simulated accurately. Thirdly, to deal with the singular point in FEM subdivision and the huge computation in traditional three-dimensional FEM, the FEM coupling 2-D earth electrode with 3-D soil based on "shell" theory is introduced. Finally, based on the suggested method, the effect of abnormal resistance region (ARR) near DC earth electrode on electric field distribution is analyzed.

Using co-precipitation to synthesize (CeO2)0.95(Y2O3)0.05 (YDC) and solid reaction method to synthesize (CeO2)0.75(ZrO2)0.25 (ZDC), and the characterization for both crystal structure and micro-structure of the two materials was conducted with X-ray diffraction (XRD) and scanning electron microscope (SEM) methods. Prepare the YDC and ZDC based limited current O2 sensor by employing platinum pasting bonding method. Sensing characteristics of the sensor were obtained at different conditions and study on the impact of temperature, O2 concentration as well as water vapor pressure on the sensing characteristics had been conducted. XRD results show that the phase structure of both YDC and ZDC is cubic phase. SEM results show that both YDC and ZDC layers are dense layers, which are then qualified to be the composition materials of the sensor. This limited current O2 sensor shows good sensing performance and conforms to the Knudsen model. Log(IL•T) depends linearly on 1000/T with R2 of 0.9904, IL depends linearly on x(O2) with R2 of 0.9726 and sensing characteristics are not affected by p(H2O).

Screen-printed carbon electrode (SPCE) is a useful technique that has been widely used in the practical application of biosensors oriented to point-of-care testing (POCT) due to its characteristics of cost-effectiveness, disposability, miniaturization, wide potential window, and easy of electrode design. Compared with gold or platinum electrodes, surface modification is difficult because the carbon surface is chemically or physically stable. Oxygen plasma can easily produce carboxyl groups on the carbon surface, which act as scaffolds for covalent bonds. However, the effect of O2-plasma treatment on electrode performance remains to be investigated from an electrochemical perspective, and sensor performance can be improved by clarifying the surface conditions of plasma treated biosensors. In this research, we compared antibody modification by plasma treated and physical adsorption, using our original immunosensor based on gold nanoparticles (AuNPs). Consequently, the O2-plasma treatment produced carboxyl groups on the electrode surface, which changed the electrochemical properties owing to electrostatic interactions. It was also found that the surface became hydrophilic, inhibiting non-specific antigen adsorption. The sensitivity was 6.5 times higher than the Limit of Detection (LOD) using physical adsorption.

A gold nanostructured film modified glassy carbon electrode (Au_film/GCE) was developed for the determination of chromium (VI) in water sample. GCE was immersed into HAuCl₄ solution (10^-3M) and electrodeposition of thin gold layer was conducted at –0.4 V (vs Ag/AgCl) for 10 min. The strong affinity between Au and Cr species resulted with increasing of Cr (VI) signal, compared with the bare glassy carbon electrode. The electrodepositing time, type of supporting electrolyte, pH, the scan rate, modulation amplitude, and modulation time were optimized using differential pulse anodic stripping voltammetry (DP-ASV). The calibration graph using accumulation time of 120 s was linear from 10 to 120 µgL^-1 with a sensitivity 1.3 x 10^-2 µA/µgL^-1. Under optimum experimental conditions, a good correlation coefficient R²=0.9971, and a low detection limit 5.5 µg/L Cr (VI) was obtained. The signal was reproducible with a relative standard deviation ±4.5 %. The developed Au_film/GCE sensor was applied for the Cr (VI) determination of in sewage water samples.

Here we report highly efficient, indium tin oxide (ITO)-free polymer solar cells (PSCs) with an ultrathin copper (Cu) film(~10 nm) coated with a thin layer of poly[(9,9-bis(3‘-(N,N-dimethylamino)propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)] (PFN) as transparent electrode. Despite of its lower far-field transmittance of the electrode, the obtained ITO-free device based on the ultrathin Cu film can delivery higher absorption efficiency than that of the device based on ITO substrate in the long wavelength region, which can be attributed to the formation of metal resonant microcavity between the opaque back metal mirror (MoO3/Al electrode) and the transparent Cu film with high reflectance. As a result, polymer solar cells based on poly[[2,6'-4,8-di(5-ethylhexylthienyl)benzo[1,2-b;3,3-b]dithiophene][3-fluoro-2[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl]] (PTB7-Th) and [6,6]-phenyl C71-butyric acid methyl ester (PC71BM) blend show a high power conversion efficiency (PCE) of 8.21 %, comparable to that of the control device based on ITO electrode (with a PCE of 9.60% ). The results demonstrate that thermally evaporated Cu thin film electrode can be promising candidate to replace ITO for highly efficient PSCs, thus may open up the possibility for massive production of PSCs with low cost.

Fires are a significant threat to people, property, and environment. One of the requirements for the buildings during fires is ensuring the safe evacuation of persons. The evacuation assessment has usually been based on a comparison of the Required Safe Egress Time (RSET) and the Available Safe Egress Time (ASET). One of the important factors influencing the safe evacuation of persons is smoke, which is an important accompanying phenomenon in the burning of polymers. The smoke layer interface is one basic barrier for effective evacuation. The current calculation technique for assessing the smoke layer interface in the Czech Republic is unsatisfactory. For this reason, a calculation technique CSN has been derived, which has been compared with the selected simple calculation techniques, the zone fire model Consolidated Model of Fire and Smoke Transport (CFAST) and the field type model Fire Dynamics Simulator (FDS). The CSN technique was also compared with a real large-scale experiment. The data were also subjected to statistical evaluation using the root mean square error method (RMSE). The deviations between the NFPA, ISO and CSN calculation techniques, the CFAST and FDS fire models and the implemented experiment ranged from 0.05 to 2.41. The established deviations indicate that the calculation technique CSN will be practically usable.

In recent years, antibacterial coatings have become a significant approach in the global fight against bacterial pathogens. Developments in materials science, chemistry and biochemistry have led to a plethora of materials and chemical compounds that have potential for creating antibacterial coatings. Nonetheless, there has been insufficient consideration given to the analysis of the techniques and technologies used to apply these coatings. Among the various inorganic coating techniques, Atomic Layer Deposition (ALD) is noteworthy. It enables the successful synthesis of high-purity inorganic nanocoatings on surfaces of complex shape and topography, while also providing precise control over their thickness and composition. ALD has various industrial applications, but its practical application in medicine is still limited. In recent years, a substantial number of papers have been published on the suggested implementation of thin films and coatings produced through ALD in medicine, notably those with antibacterial properties. The aim of this paper is to carefully evaluate and analyse the relevant literature on this subject. Simple oxide coatings, including TiO2, ZnO, Fe2O3, MgO, and ZrO2, were examined, as well as coatings containing metal nanoparticles such as Ag, Cu, Pt, and Au, and mixed systems such as TiO2-ZnO, TiO2-ZrO2, ZnO-Al2O3, TiO2-Ag, and ZnO-Ag. Through comparative analysis, we have been able to draw conclusions on the effectiveness of various antibacterial coatings of different compositions, including key characteristics such as thickness, morphology, and crystal structure. ALD has been analysed in its use for developing antibacterial coatings for various applications. Furthermore, assumptions regarding the most promising development areas have been presented.

A solution for the Prandtl-Blasius equation is essential to all kinds of boundary layer problems. This paper revisits this classic problem and presents a general Maple code as its numerical solution. The solutions were obtained from the Maple code, using the Runge-Kutta method. The study also considers convergence radius expanding and an approximate analytic solution is proposed by curve fitting. Similarly, the study resolves some boundary layer related problems and provide relevant Maple codes for these.

Recently Li et al (2019 Nature 572 624) discovered a new type of oxide superconductor Nd_0.8Sr_0.2NiO₂ with T_c = 14 K. To classify superconductivity in this infinite-layer nickelate experimental upper critical field, B_c2(T), and the self-field critical current densities, J_c(sf,T), reported by Li et al (2019 Nature 572 624), are analysed in assumption of s-, d-, and p-wave pairing symmetries and single- and multiple-band superconductivity. Based on deduced the ground-state superconducting energy gap, Δ(0), the London penetration depth, λ(0), the relative jump in electronic specific heat at T_c, ΔC/C, and the ratio of 2Δ(0)/k_BT_c, we conclude that Nd_0.8Sr_0.2NiO₂ is type-II high-κ weak-coupled single-band s-wave superconductor.

In a thin-volume photobioreactor where a concentrated suspension of microalgae is circulated throughout the established spatial irradiance gradient, microalgal cells experience a time-variable irradiance. Deploying this feature is the most convenient way of obtaining the so-called “flashing light” effect, improving biomass production in high irradiance. This work investigates the light flashing features of sloping wavy photobioreactors, a recently proposed type, by introducing and validating a Computational Fluid Dynamics model. Two characteristic flow zones (straight top-bottom stream and local recirculation stream), both effective toward light flashing, have been found and characterised: a recirculation-induced frequency of 3.7 Hz and straight flow-induced frequency of 5.6 Hz were estimated. If the channel slope is increased, the recirculation area becomes less stable while the recirculation frequency is nearly constant with flow rate. The validated CFD model is a mighty tool that could be reliably used to further increase the flashing frequency by optimising the design, the dimensions, the installation and the operational parameters of the sloping wavy photobioreactor.

Mixing layer height (MLH) is a crucial parameter for air quality modelling that is still not routinely measured. Common methods for MLH determination use atmospheric profiles recorded by radiosonde but they suffer from course temporal resolution since balloon launching is only twice a day. Recently cheap ceilometers are gaining popularity in the retrieval of MLH diurnal evolution based on aerosol profiles. This study presents a comparison of a proprietary (Jenoptik) and a free available (STRAT) algorithms to retrieve MLH diurnal cycle. The comparison is accomplished in summer season over urban area and radiosonde data is used to estimate MLHs according to parcel, lapse rate, and Richardson methods (the last algorithm is used as a reference in the study) in addition. It was found that STRAT and Jenoptik give lower MLH than radiosonde with an underestimation of about 150m and 650m respectively. Additionally, STRAT showed reasonable performance in tracking of MLH diurnal evolution. Daily MLH maximum of about 2000m was found in the late afternoon (18-19 LT). In contrast, Jenoptik algorithm showed more weaknesses, mainly attributed to its real-time operation and independent processing of a single profile. At night and during morning transition period, both lidar-based methods showed difficulties as MLH was often in the ceilometer’s incomplete overlapping zone so residual or advected aerosol layers aloft were misleadingly reported as mixing layer (ML).

Abstract: Circuit breakers are affected by multiple lightning strikes after the breaker has been tripped and can break down again, which will reduce the life of the circuit breaker and threaten the stable operation of the power system. Aiming at this problem, the paper obtained the temperature diffusion process of the inrush current process of circuit breaker opening and breaking through the schlieren technique, and combined with the existing image recognition technology to obtain the temperature characteristics of the airflow in the air gap of the contact, and the characteristics of the airflow flow. The results of the study show that the circuit breaker breakdown process generates a shock wave with a velocity approximately equal to the speed of sound under the same conditions. The maximum velocity of the airflow boundary diffusion is about 1/4 of the speed of sound under the same condition, and it decays very fast, reducing to the airflow drift velocity within 10ms after breakdown. The maximum temperature of the thermals is concentrated between 6000 and 8000 K and the temperature change is approximately inversely proportional to the square of time. The research provides the basis for the design of circuit breaker contact structure, opening speed optimization method, interrupter chamber and insulation design optimization.

In air-breathing proton exchange membrane fuel cells (Air PEM FCs), high rate of water evaporation from the cathode might influence the resistance of the membrane electrode assembly (MEA), which is highly dependent on the water content of the Nafion membrane. We propose a dead-end hydrogen anode as a means of intermediate storage of water/humidity for self-humidification of the membrane. Such inflatable bag integrated with the PEM FC has a potential in blimp applications for anode self-humidification. A dynamic numerical water balance model, validated by experimental measurements, is derived to predict the effect of MEA configuration, membrane’s hydration state, and water transfer rate at the anode on MEA resistance and performance. The experimental setup included humidity measurements, polarization and electrochemical impedance spectroscopy tests to quantify the effect of membrane hydration on its resistance in a lightweight MEA integrated with an inflatable dead-end hydrogen storage bag. Varying current density (20 mA, 40 mA and 60 mA) and cathode humidity (20, 50 and 80%) were examined and compared with the numerical results. The validated model predicts that the hydration state of the membrane and water transfer rate at the anode can be increased by using a thin membrane and thicker gas diffusion layer.

Epinephrine (EP, also called adrenaline) is a compound belonging to the catecholamine neurotransmitter family. It can cause neurodegenerative diseases such as Alzheimer’s disease, Parkinson’s disease, Huntington’s disease and amyotrophic lateral sclerosis. This work describes an amperometric sensor for the electroanalysis of EP, based on an inkjet-printed graphene electrode (IPGE), modified by a thin film of a laponite (La) clay mineral. The ion exchange properties and permeability of the prepared sensor (denoted La/IPGE) were evaluated using multi-sweep cyclic voltammetry while its charge transfer resistance was determined by electrochemical impedance spectroscopy. The results showed globally that La/IPGE exhibited more a sensitive response towards the detection of EP, in comparison with the bare IPGE. The developed sensor was directly applied for the determination of EP in aqueous solution using differential pulse voltammetry, and under optimized conditions, the calibration curve was plotted in the concentration range of 0.8 to 60 μM. The anodic peak current of EP was directly proportional to its concentration, leading to a detection limit of 0.29 μM. The sensor was successfully applied for the determination of EP in pharmaceutical preparation and best recovery rates were also obtained. The interfering effect of selected species was evaluated to highlight the selectivity of the elaborated sensor.

This study on the production of a modern natural water electrochemical antimony (II) test include the use of platinum platinum electrode electrodes. Antimony (II) was pre-concentrated on the modified electrode surface and adsorbed to the surface, oxidizing at E = -680 mV. Compared to the platinum electrode, the platinum nanoelectrode exhibited superior performance and, unexpectedly, received a higher electrochemical response. After 25 min of accumulation, time the best-defined anodic peak was obtained with 0.2 mol L^-1 KNO₃ pH 5.0. Using these parameters, the L^-1 Sb ^{2 +} calibration plot was linear over range 1 = 10⁻⁸ to 5x10⁻⁶ mol. The precision was tested by carrying out eight replicate measurements at a concentration of 2.5x10⁻⁵ mol. L^-1; the variance coefficient was 2.9%. The method was applied to analyte determination in water samples from the river. Other metal ion attack on Sb's (II) voltammetric response has been studied. In the SEM image, the nanoparticle electrode was clearly observed and characterized by X-ray diffraction and cyclic voltammetry

The detection of toxic heavy metals, especially cadmium (Cd), lead (Pb), zinc (Zn), copper (Cu), is a global problem due to ongoing pollution incidents and continuous anthropogenic and industrial activities. Therefore, it is important to develop effective detection techniques to determine the levels of contamination from heavy metals in various media. Electrochemical techniques and more specifically, voltammetry, due to its properties, is a promising method for the simultaneous detection of heavy metals. This review examines current trends related to electrode formation and analysis techniques used. In addition, there is a reference to advanced detection methods based on nanoparticles developed so far, as well as formation with bismuth and the emerging technique of screen printed electrodes. Finally, the advantages of using these methods are highlighted, while a discussion is made on the benefits arising from nanotechnology, as it gives the researcher a new idea for integrating these technologies into devices that can be used anywhere and anytime.

: In today’s rapidly expanding era of the Internet of Things (IoT) and the Industrial Internet of Things (IIoT), the emphasis on robust data security and insightful data interpreta- tion is more pronounced than ever. This research introduces a comprehensive approach to both data protection and predictive analytics, leveraging the diverse dataset TON IoT.csv, sourced from a myriad of IoT and IIoT environments. For data security, a dual-encryption technique incorporating both AES and RSA algorithms is established. Its efficacy is evidenced by a perfect match between the original and decrypted datasets, underscoring the integrity of our encryption process. Concurrently, the study ventures into predictive modeling using a modified Snake Optimization Algorithm (SOA) to streamline hyperparameter selection. This subsequently aids in the development and fine-tuning of an LSTM network, which exhibits remarkable predictive accuracy. Additionally, the paper provides an in-depth examination of various encryption methodologies like elliptic curve cryptography (ECC), Lightweight Cryptography for Cloud computing, and homomorphic encryption, while also emphasizing the nuances of encryption in cloud setups, particularly contrasting server-side with client-side encryption and efficient key management. The insights presented serve as a cornerstone for ensuing research, promising a bright future for advancements in IoT and IIoT data protection and analysis

The studies of laminar unsteady boundary layer flows is crucial for understanding laminar-turbulence transition and origins of turbulence. However, the task of finding its solutions poses a significant challenge. In this paper, we propose a novel approach by introducing a similar transformation to convert the 2D unsteady laminar boundary layer equations into a single partial differential equation. By applying this transformation, we are able to obtain the "exact" similarity solutions for the 2D unsteady laminar boundary layer equations, specifically for the case of flat plate boundary flow. Notably, this is the first time that such an exact solution has been obtained. Application of this exact solution is being used to solve Stokes' first problem in 2D boundary layer. Perspectives on the transition fron Rayleigh solution to Blasius solution is provided.

This study introduces an alternative to the existing methods for measuring ocean currents based on a recently developed technology. The SailBuoy is an unmanned surface vehicle powered by wind and solar panels that can navigate autonomously to predefined way-points and record velocity profiles using an integrated downward-looking Acoustic Doppler Profiler (ADCP). Data, collected on two validation campaigns, shows a satisfactory correlation between the SailBuoy current records and traditional observation techniques such as bottom mounted and moored current profilers and moored single-point current meter. While the highest correlations were found in tidal signals, strong current, and calm weather conditions, low current speeds and varying high wave and wind conditions reduced correlation considerably. Filtering out some events with high sea surface roughness associated with high wind and wave conditions may increase the SailBuoy ADCP listening quality and lead to better correlations. Not yet resolved is a systematic offset between the measurements obtained by the SailBuoy and the reference instruments of ± 0.03 m/s. Possible reasons are discussed to be the differences between instruments (various products) as well as changes in background noise levels due to environmental conditions.

Cross-laminated timber (CLT) possesses both good shape stability and the possible two-way force transfer ability due to its crosswise lamination. However, the transverse layers in CLT are prone to rolling shear failure under an out-of-plane load. An innovative multi-layer composite laminated panel (CLP) was developed by combining structural composite lumber (SCL) and dimension lumber to overcome the rolling shear failure while maintaining high mechanical performance and aesthetic appearance of natural wood. The mechanical properties of 5-layer CLP consisted of laminated strand lumber (LSL) and dimension lumber with different layups were evaluated by both static and modal tests. The results showed that the shear resistance, bending stiffness and moment resistance of CLP were up to 143%, 43% and 87% higher than their counterparts of regular CLT, respectively. The failure modes observed in both shear and bending tests indicated that the use of LSL in transverse layers could eliminate the potential rolling shear failure in CLT. With the lamination properties from components tests as inputs, the validity of shear analogy method was assessed by test results. The mechanical properties can be well predicted by shear analogy method except for the bending moment resistance of CLP and CLT with either rolling failure in the cross layer or tension failure in the bottom layer.

In recent decades, considerable attention has been focused on the design and development of surfaces with defined or tunable properties for a wide range of applications and fields. To this end, self-assembled monolayers (SAMs) of organic compounds offer a unique and straightforward route of modifying and engineering the surface properties of any substrate. Thus, alkane-based self-assembled monolayers constitute one of the most extensively studied organic thin-film nanomaterials, which have found wide application in antifouling surfaces, control of wettability or cell adhesion, sensors, optical devices, corrosion protection, organic electronics, among many other applications. Some of which have led technological transfer to industry. Nevertheless, recently, aromatic-based SAMs have gained in importance as functional components, particularly in molecular electronics, bioelectronics, sensors, etc., due to their intrinsic electrical conductivity and optical properties, opening up new perspectives in these fields. However, some key issues affecting device performances still need to be lifted off to ensure their full use and access to novel functionalities such as memories, sensors, or active layers in optoelectronic devices. In this context, we will present herein recent advances of p-conjugated systems-based self-assembled monolayers (e.g., push-pull chromophores) as active layer and their applications.

The wheat aleurone layer is, according to millers, the main bran fraction. It is a source of nutritionally valuable compounds, such as dietary fibres, proteins, minerals and vitamins, that may exhibit health benefits. Despite these advantages, the aleurone layer is scarce on the market, probably due to issues related to its extraction. Many processes exist with some patents, but a choice must be made between the quality and quantity of the resulting product. Nonetheless, its potential has been studied mainly in bread and pasta. While the nutritional benefits of aleurone-rich flour addition to bread agree, opposite results have been obtained concerning its effects on end-product characteristics (namely loaf volume and sensory characteristics), thus ensuing different acceptability responses from consumers. However, the observed negative effects of aleurone-rich flour on bread dough could be reduced by subjecting it to pre- or post-extracting treatments meant to either reduce the particle size of the aleurone’s fibres or to change the conformation of its components.

The deterioration of soil-cement in corrosive environment leads to the reduction of strength and the increase of permeability. Effective methods of determining deteriorated layer permeability coefficient of soil-cement are currently lacking. A laboratory test method for permeability coefficient of deteriorated layer was proposed using the modified permeability coefficient testing apparatus. According to the proposed method, the permeability coefficient of deteriorated layer can be obtained after testing the permeability coefficient of the soil-cement specimen in curing room and the equivalent permeability coefficient and deterioration depth of the soil-cement specimen in corrosion environment. Taking the marine dredger fill of Jiaozhou Bay for example, the deteriorated layer permeability coefficients of soil-cements with different cement contents were tested. It turned out that the permeability of deteriorated layer increases with the increase of age. At the beginning of curing age, larger cement content leads to smaller permeability coefficient of the deteriorated layer of soil-cement. As the curing age increases, the deteriorated layer permeability coefficient of the soil-cement with larger cement content becomes larger. The evolution of the permeability coefficient of deteriorated layer with age can be formulated as the Logistic function. This study provides a support for anti-permeability designs of soil-cement structures in corrosive environment.

Active flow control of canonical laminar separation bubbles by steady and harmonic vortex generator jets (VGJs) was investigated using direct numerical simulations. Both control strategies were found to be effective in controlling the laminar boundary-layer separation. However, the present results indicate that using the same blowing amplitude, harmonic VGJs were more effective and efficient in reducing the separated region than the steady VGJs considering the fact that the harmonic VGJs use less momentum than the steady case. For steady VGJs, longitudinal structures formed immediately downstream of injection location led to formation of hairpin-type vortices causing an earlier transition to turbulence. Symmetric hairpin vortices were shown to develop downstream of the forcing location for the harmonic VGJs as well. However, the increased control effectiveness for harmonic VGJs flow control strategy is attributed to the fact that shear-layer instability mechanism was exploited. As a result, disturbances introduced by VGJs were strongly amplified leading to development of large-scale coherent structures, which are very effective in increasing the momentum exchange, thus, limiting the separated region.

The research field of two dimensional (2D) materials strongly relies on optical microscopy characterization tools to identify atomically thin materials and to determine their number of layers. Moreover, optical microscopy-based techniques also opened the door to study the optical properties of these nanomaterials. We present a comprehensive study of the differential reflectance spectra of 2D semiconducting transition metal dichalcogenides (TMDCs), MoS₂, MoSe₂, WS₂ and WSe₂, with thickness ranging from one layer up to six layers. We analyze the thickness-dependent energy of the different excitonic features, indicating the change in the band structure of the different TMDC materials with the number of layers. Our work provides a route to employ differential reflectance spectroscopy for determining the number of layers of MoS₂, MoSe₂, WS₂ and WSe₂.

Droplet-based microfluidics has revolutionized numerous fields such as biomedical research, pharmaceuticals, drug discovery, food engineering, flow chemistry, and cosmetics. This paper presents a comprehensive study focusing on the detection and characterization of droplets with volumes in the nanoliter range. Leveraging the precise control of minute liquid volumes, we introduced a novel spectroscopic On-Chip microsensor equipped with integrated microfluidic channels for droplet generation, characterization, and sensing, simultaneously. The microsensor, designed with Interdigitated-Ring-Shaped Electrodes (IRSE) and seamlessly integrated with microfluidic channels, offers enhanced capacitance and impedance signal amplitudes, reproducibility, and reliability in droplet analysis. We were able to make analyses of droplets length in the range 1.0-6.0 mm, velocity 0.66-2.51 mm/s, droplet volume 1.07nL-113.46nL. Experimental results demonstrated that the microsensor's has a great performance in terms of droplet size, velocity, and length, with a significant signal amplitude of capacitance and impedance, and real-time detection capabilities, thereby highlighting its potential for facilitating microcapsule reactions and enabling on-site real-time detection for chemical and biosensor analyses on-chip.

The aim of this investigation is to offer a data-based scheme for predicting electrode wear in resistance spot welding. Electrode wear and alloying is one of the most significant factors that affect the mechanical properties of spot welds and the variation in weld quality. In this study, Rogowski coils and twisted pairs attached to the top and bottom electrodes were used to obtain the welding current and the inter-electrode voltage in the welding process, thereby calculating the dynamic resistance value during the welding process. The electrode diameter was obtained from the pressure exerted by the upper and lower electrodes on the carbon paper when the current was cut off and was regarded as an indicator of electrode wear. By continuously welding 0.5mm thick BH 340 steel plates until the electrode failed, the dynamic resistance signal was recorded in real time. Simultaneously, the electrode diameter after every 4 welds was also recorded. On this basis, the correlation between electrode diameter and dynamic resistance is studied. In order to quantitatively study the mapping relationship between dynamic resistance and electrode wear, 11 characteristic values were extracted from the dynamic resistance, and the stepwise regression method was used to obtain the regression formula between the characteristic values and the electrode diameter. Using new data to verify the effectiveness of the regression model, the acquired results display that the maximum error between the predicted value of the electrode diameter and the measured value obtained by the regression equation with the interactive quadratic term is 0.3 mm, and the corresponding relative error is 7.69 %. This result demonstrates that the method proposed in this paper can effectively monitor the electrode wear and failure process.

We report a new fabrication method for a fully stretchable supercapacitor based on single wall carbon nanotube (SWCNT)-coated electrospun rubber nanofibers as stretchable supercapacitor electrodes. The deposition conditions of SWCNT on hydrophobic rubber nanofibers are experimentally optimized to induce a uniform coating of SWCNT. For surfactant-assisted coating of SWCNT, both water contact angle and sheet resistance were the lowest compared to the cases with other surface treatment methods, indicating the most effective coating approach. The excellent electromechanical properties of this electrode under the stretching condition is demonstrated by the measurement of Young’s modulus and normalized sheet resistance. This superb tolerance of the electrode with respect to stretching results from i) high aspect ratios of both nanofiber templates and the SWCNT conductors, ii) highly elastic nature of rubbery nanofiber, and iii) strong adherence of SWCNT-coated nanofiber on the elastic ecoflex substrate. Electrochemical and electromechanical measurements on the stretchable supercapacitor devices reveal that the volumetric capacitance (15.2 F cm-3 at 0.021 A cm-3) of the unstretched state is maintained for strains of up to 40 %. At this level of strain, the capacitance after 1,000 charge/discharge cycles is not significantly reduced. The high stability of our stretchable device suggests potential future applications in various types of wearable energy storage devices.

Electrochemical-mechanical interactions, in particular pressure-induced ones, have been identified to be a cause for lithium-plating in lithium-ion cells. Mechanically-induced porosity inhomogeneities in the separator layers due to electrode expansion during charging especially lead to cell internal balancing currents and can cause localized plating. To identify cell-format and cell-material dependent mechanical weak spots, a layer-resolved mechanical simulation of different cell types and cell-material combinations is presented in this work. The simulation results show distinctive layer strain patterns for different cell-types that coincide with localized lithium-plating found in post-mortem cells. Additionally, the effects of cell bracing in battery modules is investigated and a method to mitigate the increased layer strain due to bracing counterforces is proposed that also increases cell energy density for hardcase-type automotive cells.

Passive balancing is a traditional choice for lithium-ion battery packs although it is regarded as highly inefficient. One opportunity to improve traditional balancing in sub-medium size battery packs is to combine two balancing methods: passive and active. Statistical analysis have been performed to rationalize battery pack division in smaller packs and use of higher level selective charging method to decrease losses of passive balancing. An experimental balancing prototype have been designed and tested for efficiency. Results indicate energy performance degradation if cells of the pack are with low capacity variation. Proposed balancing approach could improve performance under high cell mismatch conditions.

The newly developed friction-interlocking armor unit, called ‘Double cube’ (DC), has been designed to improve the performance of the concrete armor unit used in river/marine structures against currents/waves actions. DC unit, is an octagonal-shaped block, made up of two parts: an upper cube set on a lower base that is either square or octagonal in shape. The innovative design aims to provide a good performance in terms of stability, high tolerance placement with various contact points and ease of placement. DC’s shape and placement enhance the stability by bringing the center of gravity closer to the underlayer and providing a large contact surfaces with surrounding blocks that reduce the chance of extraction and limit movements (rocking, lifting) via "keystone" effect. The characteristics of this new unit provides a relatively high hydraulic stability number for the armor layer (NS=2.9), a favorable hydraulic performance due to energy dissipation from turbulence and aeration, as well as a high roughness coefficient (γf≈0.46) helping to reduce the overtopping.

The use of interleaving material with viscoelastic properties is one of the most effective solutions to improve the damping capacity of CFRP laminates. Improving composite damping without threatening mechanical performance is challenging and the use of nanomaterials should lead to the target. In this paper, the effect of a nanostructured interlayer based on Graphite Nanoplatelets (GNPs) on the damping capacity and fracture toughness of CFRP laminates has been investigated. High-content GNP/Epoxy (70wt/30wt) coating was sprayed on the surface of CF/Epoxy prepregs at two different areal weight (10 and 40 g/m2) and incorporated at the middle-plane of a CFRP laminate. The effect of the GNP areal weight on viscoelastic and the mechanical behaviour of the laminates was investigated. Coupons with low-areal weight GNP interlayer showed a 25% increase in damping capacity with a trivial reduction of the elastic modulus. Moreover, a reduction in interlaminar shear strength (ILSS) and fracture toughness (both mode I and mode II) was observed in the composites with GNPs interlayer. GNPs alignment and degree of compaction reached during process were found as key parameters on material performances. By increasing the areal weight a mitigation on the mechanical performances drop was achieved (-15%).

The aim of this paper is to present a comprehensive overview of the main aims and scopes in screening of botanicals, a task which thin-layer chromatography (TLC) is on an everyday basis confronted with and engaged in. Stunning omnipresence of this modest analytical technique (both in its standard format (TLC) and the high-performance one (HPTLC), either hyphenated or not) for many analysts might at a first glance appear chaotic and random, with an auxiliary rather than leading role in research, and not capable of issuing meaningful final statements. Based on these reflections, our purpose is not to present a general review paper on TLC in screening of botanicals, but a blueprint rather (illustrated with a selection of practical examples), which highlights a sovereign and important role of TLC in accomplishing the following analytical tasks: (i) solving puzzles related to chemotaxonomy of plants, (ii) screening a wide spectrum of biological properties of plants, (iii) providing quality control of herbal medicines and alimentary and cosmetic products of biological origin, and (iv) tracing psychoactive plants under forensic surveillance.

In this paper, we propose a lightweight physical layer aided authentication and key agreement (PL-AKA) protocol in the internet of things (IoT). Conventional evolved packet system AKA (EPS-AKA) used in long-term evolution (LTE) systems may suffer from congestions in core networks by the large signaling overhead as the number of IoT devices increases. Thus, in order to alleviate the overhead, we consider a cross-layer authentication by integrating physical layer approaches to cryptography-based schemes. To demonstrate the feasibility of the PL-AKA, universal software radio peripheral (USRP) based tests are conducted as well as numerical simulations. The proposed scheme shows a significant reduction in signaling overhead compared to the conventional EPS-AKA in both simulation and experiment. Therefore, the proposed lightweight PL-AKA has the potential for practical and efficient implementation of large-scale IoT networks.

Few-layer graphene oxide (GO) has shown none or very weak cytotoxicity and anti-proliferative effects in a wide range of cell lines such as glyoma cells and human skin HaCaT cells, in concentrations up to 100 µg/mL However, multi-layer GO has been hardly explored in the biomedical field. Thus, multi-layer GO was examined here in human keratinocyte HaCaT cells treated with different concentrations ranging from 0.01 to 150 µg/mL during different periods of times (3, 12 and 24 hours). The results of this study showed a time-concentration dependence with two non-cytotoxic concentrations (0.01 and 0.05 µg/mL) and a median effective concentration value of 4.087 µg/mL at 24 hours of GO exposure. Contrary to what has been reported for few-layer GO, cell proliferation of the HaCaT cells in contact with the multi-layer GO at 0.01 μg/mL showed identical proliferative activity compared to an epidermal growth factor (1.6-fold greater than the control group) after 96 hours. The effects of the multi-layer GO on the expression of 13 genes (SOD1, CAT, MMP1, TGFB1, GPX1, FN1, HAS2, LAMB1, LUM, CDH1, COL4A1, FBN and VCAN) at the non-cytotoxic concentrations of GO in the HaCaT cells were analyzed after 24 hours. Thus, the lowest non-cytotoxic GO concentration was able to up-regulate the CAT, TGFB1, FN1 and CDH1 genes, which confirms the great potential of multi-layer GO in the biomedical field.

In this work we have critically reviewed the processes in high-temperature sublimation growth of graphene in Ar atmosphere using enclosed graphite crucible. Special focus is put on buffer layer formation and free charge carrier properties of monolayer graphene and quasi-freestanding monolayer garphene on 4H-SiC. We show that by introducing Ar at different temperatures, TAr one can shift to higher temperatures the formation of the buffer layer for both n-type and semi-insulating substrates. A scenario explaining the observed suppresed formation of buffer layer at higher TAr is proposed and discussed. Increased TAr is also shown to reduce the sp3 hybridization content and defect densities in the buffer layer on n-type conductive substrates. Growth on semi-insulating substrates results in ordered buffer layer with significantly improved structural properties, for which TAr plays only a minor role. The free charge density and mobility parameters of monolayer graphene and quasi-freestanding monolayer graphene with different TAr and different environmental treatment conditions are determined by contactless terahertz optical Hall effect. An efficient annealing of donors on and near the SiC surface takes place in intrinsic monolayer graphene grown at 2000∘C, and which is found to be independent of TAr. Higher TAr leads to higher free charge carrier mobility parameters in both intrinsically n-type and ambient p-type doped monolayer graphene. TAr is also found to have a profound effect on the free hole parameters of quasi-freestanding monolayer graphene. These findings are discussed in view of interface and buffer layer properties in order to construct a comprehensive picture of high-temperature sublimation growth and provide guidance for growth parameters optimization depending on the targeted graphene application.

A novel high-voltage powerline inspection system is investigated, which consists of the cooperated ground vehicle and drone. The ground vehicle acts as a mobile platform that can launch and recycle the drone, while the drone can fly over the powerline for inspection within limited endurance. This inspection system enables the drone to inspect powerline networks in a very large area. Both vehicle’ route in the road network and drone’s routes along the powerline network have to be optimized for improving the inspection efficiency, which generates a new two-layer point-arc routing problem. Two constructive heuristics are designed based on “Cluster First, Rank Second” and “Rank First, Split Second”. Then local search strategies are developed to further improve the quality of the solution. To test the performance of the proposed algorithms, practical cases with different-scale are designed based on the road network and powerline network of Ji’an, China. Sensitivity analysis on the parameters related with the drone’s inspection speed and battery capacity is conducted. Computational results indicate that technical improvement on the inspection sensor is more important for the cooperated ground vehicle and drone system.

In this article, bio-composites derived from starch-glycerol biodegradable matrix reinforced with jute fibers have been fabricated using the wet hand lay-up and compression moulding techniques. Samples having different weight percentages of jute fiber in the starch matrix have been analysed. The fibers surface was chemically treated by alkaline sodium hydroxide for improving the interphase bonding between fiber and matrix. Tensile test for the composites were done and the sample with highest tensile strength was selected for further tests that included water absorption, scanning electron microscopy and thermal analysis. It has been concluded that the ultimate tensile strength was found to be maximum for the composition of 15% fiber by weight composite as 7.547 MPa without epoxy coating and 10.43 MPa with epoxy coating. The major disadvantage of bio-composite is its high water absorption property, which in this study has been inhibited by the epoxy resin layer. Herein, the results of various tests done disclose a noteworthy improvement in the overall properties of bio-composite, in comparison to the neat biodegradable starch matrix.

Electroluminescence (EL) is an innovative technology in the lighting area. The EL device's main structure consists of a phosphor layer sandwiched by two electrodes. In this work, several alternating current EL devices have been developed by applying a set of sequential layers with combinations of in-house prepared inks and commercially available ink as a phosphor layer. A flexible polyester textile substrate was functionalized with inks by spray coating technique, after knife-coated an interfacial layer directly on the surface. A thorough study was carried out on the phosphor layer composition to optimize the EL device performance, more precisely the illuminance intensity and the illuminance homogeneity. The developed phosphor layer was composed of zinc sulphide doped with copper (between 30.0 to 38.1 wt%) and diluted by using a diluent at different ratios (28.0 to 35.5 wt%). The best peak illuminance intensity of 61 lux was obtained when the phosphor ink presented 35.4% ZnS:Cu and was diluted with 33.0% diluent. The aim of this study to determine the best formulation of the phosphor layer, which can be highly promising for further developments of EL devices, taking in account different applications in market.

The paper proves the existence of a family of axisymmetric equilibrium figures as solutions of a stationary problem with unknown boundaries for the Navier–Stokes equations corresponding to the slow rotation of a viscous compressible two-layer liquid mass about some axis. It is assumed that the liquids are barotropic, capillary and have different viscosities, the internal fluid being bounded by a closed surface. This interface does not intersect with the external boundary of the cloud. The proof is based on implicit function theorem and carried out in the Hölder spaces.

The work presented in this paper represents a preliminary study on the performance of the new Silicon tracker layer, the Layer 0 (L0), that will be installed on top of the Alpha Magnetic Spectrometer (AMS-02), at the end of 2024. AMS-02 is a cosmic rays (CR) detector that has been operating on the International Space Stations (ISS) since May 2011. Thanks to its 9-layer Silicon tracker, this apparatus can perform high energy CR measurements with an unprecedented level of statistics and precision. However, high Z (Z $\ge 15$) CR nuclei statistic is strongly affected by fragmentation along the detector: with the installation of the new Silicon layer will be possible to achieve new unique high energy (TeV region) measures for those nuclei along with increased statistics for all nuclei up to Zinc. To achieve this, a Silicon ladder prototype, that will be part of the final Silicon layer, has been exposed to an ions test beam at the super-proton-synchrotron (SPS) of the CERN to characterize its charge resolution and the readout electronics. Preliminary results have shown a charge resolution of 10 $\%$ for nuclei up to Z=7.

The design of water Vessel fender system can minimize impact energy, which could result in severe vessel or offshore structure damage during collision. In order to protect Offshore structures and vessels from damage after impact, a Fender design approach is proposed which uses Soft materials like rubber, sand, inflated rubber tube, etc. to reduce damage on impacted vessels as well as offshore structures like wind turbines, bridges, oil drilling platforms in water etc. The fender is designed in such a way that it can handle vessels made of different material, sizes, and weights.The proposed solution is a fender consisting of a number of layers of soft sandwich materials, each layer getting softer as it moves away from the structure i.e. Hard-Soft fender design which can absorb impact energy upon collision. To handle lighter vessels made of soft or brittle materials, the outer layer is made of inflatable or Very soft foam rubber; however, the inner layer covering the offshore structure is made of hard material to handle heavy vessels made of hard material such as steel. Furthermore, the use of sand as a natural fender along waterways such as narrow channels is also proposed to reduce the cost of fender installation and catastrophic vessel impact damage on rocky ground since it produces less deformation just like rubber fender as demonstrated in the simulation. Finite Element Analysis using ANSYS software, Explicit Dynamic Autodyn, was performed. The results showed a considerable decrease in the total deformation and internal energy of the vessel and fended structure when collision occurs. Furthermore, the result showed that Hard-Soft fender layer performs much better than Soft-Hard-Soft followed by Soft-Hard Fender layer design.

Strained layer superlattice (SLS) material system is being considered for large format, small-pitch and low-cost focal plane arrays for different applications. To address difficulties associated to focal plane arrays fabrication arising from mesa-isolation etching or complex surface treatment/ passivation process, planar structures have been considered. In this work, the recent progress on planar SLS photodetector using ion-implantation for device isolation is presented. The devices are presented here are nBn and pBn heterostructure InAs/InAsSb SLS photodetector, where Zn and Si were chosen as the ion implants, respectively. The electrical and optical performance of the devices were compared along with comparison with mesa-etched device, to give deeper view of the device performance.

We investigate the flow structure and dynamics of moderate-Rayleigh-number ($Ra$) thermal convection in a two-dimensional inclined porous layer. Direct numerical simulations (DNS) confirm the emergence of $\mathit{O}(1)$ aspect-ratio large-scale convective rolls, with one `natural' roll rotating in the counterclockwise direction and one `antinatural' roll rotating in the clockwise direction. As the inclination angle $\phi$ is increased, the background mean shear flow intensifies the natural-roll motion, while suppressing the antinatural-roll motion. Moreover, our DNS reveal---for the first time in single-species porous medium convection---the existence of \emph{spatially-localized} convective states at large $\phi$, which we suggest are enabled by subcritical instability of the base state at sufficiently large inclination angles. To better understand the physics of inclined porous medium convection at different $\phi$, we numerically compute steady convective solutions using Newton iteration and then perform secondary stability analysis of these nonlinear states using Floquet theory. Our analysis indicates that the inclination of the porous layer stabilizes the boundary layers of the natural roll, but intensifies the boundary-layer instability of the antinatural roll. These results facilitate physical understanding of the large-scale cellular flows observed in the DNS at different values of $\phi$.

Poly(3,4-ethylenedioxythiophene) (PEDOT) with a dopant of polystyrene sulfonate (PSS), namely PEDOT:PSS, has been mostly used as counter electrode to give a high performance of dye-sensitized solar cells (DSSCs). Recently, PEDOT doped by carrageenan (PEDOT:Carrageenan) was introduced as a new material to be applied on DSSC as electrolyte. PEDOT:Carrageenan has a similar synthesis process as PEDOT:PSS owing to their similar ester sulphate (-SO3H) groups in both PSS and carrageenan. This review provides an overview of the different roles between PEDOT:PSS as counter electrode and PEDOT:Carrageenan as electrolyte for DSSC applications. The synthesis process and characteristics of PEDOT:PSS and PEDOT:Carrageenan were also described in this review. In conclusion, we found that PEDOT:PSS as counter electrode has the main roles of transferring electrons from the external circuit and accelerating the reduction reaction of redox coupled with its high electrical conductivity and high electrocatalytic activity. As electrolyte, PEDOT:Carrageenan has not shown the main role as an electron transfer from counter electrode to regenerate the dye-sensitized at the oxidized state due to its low ionic conductivity. Therefore, PEDOT:Carrageenan still obtained a low performance of DSSCs. Additionally, the future perspective and challenges of using PEDOT:Carrageenan as both electrolyte and counter electrode are described in detail.

In this paper, MnO2 nanowire (MnO2-NW) modified carbon paper (CP) electrode was developed as a novel electrochemical sensor for sensitive determination of tetrabromobisphenol A (TBBPA). MnO2 nanowire was prepared by a hydrothermal synthesis method, and the morphology and structure of MnO2 were characterized using scanning electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. Electrochemical performance of TBBPA on MnO2-NW/CP was investigated by cyclic voltammetry, and the result confirmed that MnO2-NW/CP exhibited excellent sensitive for the determination of TBBPA due to the high specific surface area and good electrical conductivity of the nanowire-like MnO2. Moreover, the important electrochemical factors such as pH value, incubation time and modified material proportion were systematically studied to improve the determination sensitivity. The interferences from similar structure compounds on TBBPA have also been investigated. Under the optimal conditions, MnO2-NW/CP displayed the linear range of 70 500 nM for TBBPA with the detection limit of 3.1 nM, which was superior to some electrochemical methods in references. The work presents a novel and simple method for the determination of TBBPA.

In two previous papers, we calculated the dielectrophoresis (DEP) force and corresponding trajectories of high- and low-conductance 200-µm 2D spheres in a square 1x1mm chamber with plane-versus-pointed, plane-versus-plane and pointed-versus-pointed electrode configurations by applying the law of maximum entropy production (LMEP) to the system. Here, we complete these considerations for configurations with four-pointed electrodes centered on the chamber edges. The four electrodes were operated in either object-shift mode (two adjacent electrodes opposite the other two adjacent electrodes), DEP mode (one electrode versus the other three electrodes), or field-cage mode (two electrodes on opposite edges versus the two electrodes on the other two opposite edges). As in previous work, we have assumed DC properties for the object and the external media for simplicity. Nevertheless, every possible polarization ratio of the two media can be modeled this way. The trajectories of the spherical centers and the corresponding DEP forces were calculated from the gradients of the system’s total energy dissipation, described by numerically-derived conductance fields. In each of the three drive modes, very high attractive and repulsive forces were found in front of pointed electrodes for the high and low-conductance spheres, respectively. The conductance fields predict bifurcation points, watersheds, and trajectories with multiple endpoints. The high and low-conductance spheres usually follow similar trajectories, albeit with reversed orientations. In DEP drive mode, the four-point electrode chamber provides a similar area for DEP measurements as the classical plane-versus-pointed electrode chamber.

The administration of regional neuraxial analgesia for pain relief during labor is widely recognized as a safe and effective method involving medication delivery into the epidural or subarachnoid space in the lower back. This study proposes an innovative semantic image segmentation methodology emphasizing enhanced interpretability using convolutional Random Fourier Features and layer-wise weighted class-activation maps tailored explicitly for foot segmentation in regional analgesia monitoring. Namely, our contribution is twofold: i) a novel Random Fourier Features layer is introduced to deal with image data to enhance three well-known architectures (FCN, UNet, and ResUNet); ii) three novel quantitive measures are presented to evaluate the interpretability of a given deep learning model devoted to segmentation tasks. Our approach is rigorously evaluated on a demanding dataset of foot thermal images from pregnant women who received epidural anesthesia. Its small size and considerable variability characterize the dataset. Our validation results demonstrate that the proposed methodology not only achieves competitive foot segmentation performance but also significantly enhances the explainability of the process, rendering it well-suited for applications such as epidural insertion during labor.

Nowadays industrial dryers are used instead of traditional methods for drying. In designing dryers suitable for controlling the process of drying and reaching a high quality product, it is necessary to predict the instantaneous moisture loss during drying. For this purpose, ten mathematical-experimental models with a neural network model based on the kinetic data of pistachio drying are studied. The data obtained from the cabinet dryer will be evaluated at four temperatures of inlet air and different air velocities. The pistachio seeds will be placed in a thin layer on an aluminum sheet on a drying tray and weighed by a scale attached to the computer at different times. In the neural network, data are divided into three parts: educational (60%), validation (20%) and test (20%). Finally, the best mathematical-experimental model using genetic algorithm and the best neural network structure for predicting instantaneous moisture are selected based on the least squared error and the highest correlation coefficient.