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Hybrid nanofluids were expressed by heat-transfer fluids into greater surface dispersion capabilities, stability and diffusion related for traditional nanofluids. The effort on the flow of volumetric entropy generation and convective heat transport of MHD hybrid nanofluid is considered. Hybrid nanofluid involves the field over the orderly stretchable surface for variable heat flux with the resistance of electric field. Effect on convective heating and nonlinear thermal radiation is again contained in the interpreted figure. Mathematical equations such as momentum, energy, conservation of mass and entropy were collected as conversion to governing partial differential equations by ordinary differential equations, utilizing similarity variables. An efficient finite element method (FEM) is used. Numerical calculations were accomplished for silver–magnesium oxide water (Ag-MgO/H2O) hybrid nanofluid and conventional silver water (Ag-H2O) nanofluid. The graphs were created by the temperature, velocity, and entropy profiles. to analyse the impact on governing parameters. These skin friction and heat transfer rates are analysed through regression analysis. The important allegation expressed by the hybrid Nanofluid has the best heat transfer rate, which is related to convectional nanofluid. Further, It raised the Brinkman number and Reynolds number and developed a total entropy of the structure. [ABSTRACT FROM AUTHOR]

The effect of annealing treatment on the electromigration (EM) resistance of low-temperature Cu/Sn-57Bi-1Ag (600 μm)/Cu solder interconnects has been investigated. The annealing treatment of as-soldered Cu/Sn-57Bi-1Ag/Cu solder interconnects caused the obvious coarsening of Bi phases in the bulk solders and a slight reduction in the electric resistance of the solder interconnects. The coarsening of the Bi phases induced a decrease in the Bi/β-Sn phase boundaries and thus a decrease in the EM-induced atomic diffusion flux of Bi atoms during the subsequent current stressing, resulting in the segregation of a thinner Bi phase layer at the anode and a lower increase rate of electric resistance of the solder interconnects. The longer the annealing time, the higher the EM resistance of the solder interconnects. The reductions in both the effective diffusion coefficient of the Bi atoms and the electric resistivity of the bulk Sn-57Bi-1Ag solders induced by the annealing treatment were responsible for the higher EM resistance of low-temperature Sn-57Bi-1Ag solder interconnects. [ABSTRACT FROM AUTHOR]

Highlights Structural battery composites (SBCs) represent an emerging multifunctional technology in which materials functionalized with energy storage capabilities are used to build load‐bearing structural components. However, due to the liquid electrolyte contamination in structural battery electrolyte (SBE) and the large volume expansion of active battery materials, the poor interlayer interfacial in multilayer SBCs often causes difficulties in practical use. In this study, a new porous LiFePO4‐graphite SBC is designed and fabricated by independently distributing battery materials and resin matrix on carbon fiber fabric in pattern lattice form to prepare electrodes prepreg. The cured porous composite framework supports the load‐bearing function while limiting the electrochemical reaction in liquid electrolyte within lattices. The electrodes show reversible electric resistance after 3000 bending cycles with radius as small as 10 mm. The mechanical properties enhance significantly with tensile strength of 486.1 MPa and Young's modulus of 9.1 GPa compared to that with a liquid–solid biphasic mixed SBE structure. The SBC also exhibits a favorable capacity of 27.8 mAh/g at 0.1C. This straightforward integration path of mechanical and electrical functionalities is compatible with the manufacturing process of aerospace composite structures, which will provide an efficient and convenient energy supply solution for distributed electronics. A porous full‐cell structural battery composite (SBC) was designed and fabricated with prepregs. A suspension deposition and volatilization method was developed for robust battery material coating. Electrodes layer exhibited reversible electric resistance after 3000 tensile/bending cycles. The tensile strength and modulus increased significantly compared to the SBC with liquid–solid biphasic mixed structural battery electrolyte. Coordinated integration path was completely compatible with the manufacturing process of aerospace composite structures. [ABSTRACT FROM AUTHOR]

To be able to carry out a high-quality analysis of the operation and design of elevator systems with a driving pulley, it is necessary to determine the size of the losses that occur in the drive mechanism and elevator guide rails. The paper defines an experimental procedure for determining the losses and the efficiency coefficient of elevator facilities depending on the relative load of the cabin in operational conditions. The experiment was carried out on a passenger elevator with a rated load of 320 kg and a lifting height of 28 m. An analysis of the resistance, i.e., the source of power losses in vertical lifting devices, was performed, the most significant of which occur and are especially pronounced in worm gear reducers and on the guiding system of the cabin and counterweight, where the type of guiding elements also has an influence. A particular problem is expressed due to the changing state of the contact surfaces (between the guide rails and the guide shoes) during exploitation and the eccentric loading of the cabin. Also, the paper analysed the obtained measurement results to determine the dependence of the efficiency coefficient of the facility concerning the relative load of the cabin. [ABSTRACT FROM AUTHOR]

The contact finger electrical connection structure is a crucial component of high voltage bushings, and its safety and reliability directly impact the operational stability of the bushing. To investigate electrical contact performance of the contact finger under eccentric conditions, a three‐dimensional electrical, thermal, and force multi‐physics coupling calculation model was established. Additionally, a test platform was constructed to measure electrical contact characteristics of the contact finger. The contact characteristics of the contact finger when the male head was axially deflected and radially offset compared to the female head were obtained. The research findings indicate when the male head deflects axially, the contact force changes of the contact finger blades on both sides are opposite. Moreover, as the axial deflection angle of the male head increases, the resistance of the electrical connection structure shows a rising‐slow decreasing‐fluctuating trend. The resistance is highest at 3°, with a resistance increase rate of 7.35%. Furthermore, the resistance of the electrical connection structure varies with the radial offset of the male head, following a power function. Contact failure occurs when the radial offset is 1.31 mm, and the resistance increase rate reaches 24.9% at a radial offset of 1.58 mm. [ABSTRACT FROM AUTHOR]

Particles regularly tribocharge in collisions. Here, we study how long charges can persist on such particles in the environment of a protoplanetary disc. We set up three complementary experiments to quantify discharge time-scales. We first directly measure the time dependency of charge on triboelectrically charged objects. For this aspect, we performed two long-time experiments under different environmental conditions. We find that the charge persists on the tribocharged bodies on time-scales between minutes and years. Discharge might be mediated by external ions or internally, by conduction. To constrain the latter, we also determined the specific electric resistance of dust samples as simulants for dust aggregates in protoplanetary discs. In this third experiment, we see an increase in resistivity at decreasing ambient pressure up to the limit of the instrument. These findings are consistent with the assumption that water on all relevant surfaces including dust grains within the pore space of aggregates is the main driver of discharge. Under disc conditions, the charge might persist for weeks to years. This leaves net-charged isolated grains in dense parts of the mid-plane of protoplanetary discs charged in between collisions. [ABSTRACT FROM AUTHOR]

Load shifting for existing electric resistance water heaters (EWHs) presents a potential solution to utility challenges caused by the temporal mismatch between solar generation and electricity consumption. A case study in the Florida Power & Light (FPL) territory for both an individual and a fleet of EWHs evaluates this potential. Two optimization problems are solved using mixed-integer linear programming to maximize solar self-consumption and minimize electricity cost for an individual EWH. Compared to default operation, the solar maximization strategy results in nearly twice as much heating electricity from solar (80% vs. 42%) and 14% increased electricity cost based on FPL rates. An energy balance approach shows the aggregate impact of all FPL EWHs on days of peak and minimal load, June 25th and December 3rd. Publicized goals of increased solar capacity by 2030 will cause changes to the FPL net load, total load minus solar generation. The four million EWHs in the territory can stabilize the net load in 2030 as shifting their load causes a 24% decrease in the standard deviation of the predicted load on both dates. These results encourage widespread adoption of retrofit devices that control EWHs based on solar generation profiles and water consumption schedules. [ABSTRACT FROM AUTHOR]

The effect of peak temperature for post-weld heat treatment (PWHT) on the dissolution of Nb-rich carbonitrides, Nb(C,N), in the weldline of an electric resistance welded (ERW) X70 grade pipeline steel was investigated. Selected-area electron diffraction patterns and corresponding electron energy loss spectroscopy mappings revealed both Nb-rich carbonitrides and Ti-rich nitrides, (Ti,Nb)N, in the sample heat-treated to 1080 °C peak temperature. However, only Ti-rich nitrides were revealed in the sample heat-treated to 1220 °C peak temperature. During continuous heating to higher than the Ac3 temperature, i.e., near 1100 °C temperature, the dissolution of Nb(C,N) was observed in dilation and derivative of dilation. This experimental result agreed with the predictions by a DICTRA model. Furthermore, a phenomenological model was developed to explain the volume shrinkage during the dissolution of Nb(C,N) precipitates. [ABSTRACT FROM AUTHOR]

The development of electric resistance is a key factor affecting the performance of conductive concrete, especially the electrical–thermal performance. In this work, the effects of different influencing factors (including the water-to-binder ratio, coarse aggregate content and carbon fiber (CF) content) on the electric resistance of conductive concrete were systematically investigated. At the same time, ohmic heating (OH) curing was applied to fabricate CF-reinforced conductive concrete (CFRCC) under a negative temperature environment at −20 °C. The effects of different factors on the electrothermal properties (curing temperature and conductive stability) of the samples were studied. The mechanical strengths of the CFRCC cured by different curing conditions were also tested, and the feasibility of OH curing for preparing CFRCC in a negative-temperature environment was verified at various electric powers. This work aims to give new insights into the effects of multiple factors on the performance of CFRCC for improved concrete construction in winter. [ABSTRACT FROM AUTHOR]

Here, sulfur doped N-rich nitrogen carbon (S@CN) was designed to reduce uranium(VI). S doping replaced the lattice nitrogen of CN, which make 2.0S@CN possess narrower bandgap, more negative conduction band, higher photocurrent intensity, lower electric resistance and emission intensity than those of CN, thus showing higher photocatalysis activity. The photocatalytic uranium(VI) separation rate by 2.0 S@CN almost approached 100% under irradiation, which was about twice that of CN. Besides, the uranium(VI) separation rate of 2.0 S@CN after fifth cycles was still more than 90%, meaning that 2.0 S@CN had good recoverability, which possessed great potential for water environment renovation. [ABSTRACT FROM AUTHOR]

Supporting sustainable development, contributing to reducing waste that causes environmental damage, and reducing the use of natural materials are part of preserving the environment and society. This is done by highlighting the manufacture of sustainable concrete pavement of acceptable quality and according to specifications. The authors previously produced a concrete pavement mixture with optimal properties by partially replacing the Portland cement with 55 wt.% of the ground granulated blast furnace slag (GGBFS) in addition to partially replacing the virgin aggregates with 30 wt.% of recycled aggregate from crushed rigid pavement. The goal of this research work is to produce a self-sensing rigid pavement mixture from wastes with high mechanical properties, that is better than regular concrete and less expensive. The new novel mixture has the ability to detect earlier the damages that occur to the concrete pavement so as to obtain a longer life by periodically maintaining the pavement on time. The previous mixture was improved by adding chopped steel shaving fibers with lengths ranging from 20-60 mm in four different volumetric ratios. These are 0.7%, 1%, 1.1%, and 1.2%. The results were compared with those of the basic mixture, and a decrease in workability and slump values were noticed. Moreover, significant improvements in the mechanical properties were obtained. The concrete's resistance to the applied loads increased by increasing the percentage of steel shaving in the mixtures, due to the increasing of cohesion forces within the mixture. The self-sensing capability for the developed mixtures was tested by measuring the changes in the electrical resistance under different types of mechanical loadings. The results showed that the direction of the applied load and the proportion of steel shavings affect the self-sensing properties in terms of the fractional variation in the electrical resistance (FVER, %), which highlights the importance of using steel shavings in producing smart concrete pavements from reused resources more efficiently and highly cost-effectiveness. [ABSTRACT FROM AUTHOR]

The aim of this study was to find a way to improve earthquake resistance performance more effectively through various reinforcement methods between a cabinet bottom and concrete slab, which is a vulnerable connection in the event of earthquake. In order to improve the earthquake resistance performance of an electric cabinet, methods such as installing a vibration isolation device, increasing the number of connecting bolts between the cabinet bottom panel and base channel, welding a steel grid to the cabinet bottom panel, and so on, were considered and, in order to compare the performance in each case, a three-axis shaking table test was performed. As a result of comparing the seismic performance of each case according to the acceleration response, it was found that the reduction of seismic force was best when applying the vibration isolation device. However, there is a disadvantage in that the spatial and temporal limitations are large and the unit price is high for application in the field. For this reason, it is predicted that the method of ensuring the higher rigidity of an electric cabinet by increasing the number of connecting bolts, as proved through this study, would be a more economical and realistic seismic performance method in field applications. [ABSTRACT FROM AUTHOR]

Naturally fermented dairy products are an important component of the human diet. They are a valuable source of nutrients as well as vitamins and minerals. Their importance as a source of probiotic bacterial strains should not be overlooked. A number of studies highlight the positive effects of species of the probiotic lactic acid bacteria on the intestinal microbiome and the overall homeostasis of the body, as well as a complementary treatment for some diseases. However, data on the effects on the intestinal epithelial cells of postmetabolites released by probiotic bacteria are incomplete. This is likely due to the fact that these effects are species- and strain-specific. In the present study, we investigated the effects of postmetabolites produced by a pre-selected candidate probiotic strain Limosilactobacillus fermentum on HT-29 intestinal epithelial cells. Our data showed a pronounced proliferative effect, evaluated by flow cytometry, quantification of the cell population and determination of the mitotic index. This was accompanied by the stabilization of the cell monolayer, measured by an increase in TEER (transepithelial electric resistance) and the reorganization of actin filaments. The data obtained are a clear indication of the positive effects that the products secreted by L. fermentum strain 53 have on intestinal epithelial cells. [ABSTRACT FROM AUTHOR]

This study analyzes the effect of the temperature coefficient of electric resistance on the thermal performance of a film heater for satellite applications. A heating element in the film heater was fabricated using silver paste and screen-printing technology. The temperature distributions of the film heater were numerically simulated on the basis of the heat transfer equation. The temperature coefficient of resistance was evaluated by measuring the film-heater temperature at various voltages using a forward-looking infrared (FLIR) camera. The results showed that the electric resistance linearly increased with a temperature variation. By considering the temperature coefficient of electric resistance, the error of numerical simulation decreased from 22.5% to 10%. The voltage required to reach the maximum allowable temperature at a given sink temperature was higher than the design voltage when the temperature coefficient was not considered. This indicated that greater power would be required to operate the film heater in real satellite applications. [ABSTRACT FROM AUTHOR]

Rich biological information in sweat provides great potential for health monitoring and management. However, due to the complexity of sweat, the development of environmentally friendly green electronic products is of great significance to the construction of ecological civilization. This study utilized a simple combination of polystyrene sulfonate sodium (PSS) and filter paper (FP) to prepare cellulose materials coated with conductive polymers, developing an electrochemical sensor based on the modified materials. The mechanical and electrochemical properties of the fabricated PSS/FP membrane were optimized by adjusting the feeding dosage of PSS. The realized PSS/FP composite containing 7% PSS displayed good conductivity (9.1 × 10−2 S/m), reducing electric resistance by 99.2% compared with the original FP membrane (6.7 × 10−4 S/m). The stable current of the membrane in simulated sweat under different pH environments is highly correlated with the pH values. Additionally, when the membrane is exposed to simulated sweat with varying ion concentrations, the current signal changes in real time with the concentration variations. The response time averages around 0.3 s. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) as emerging material have drawn much attention to apply to the field of water splitting. In this paper, layered NiFe-MIL-53 and nanoflower-like CoFe-MOF-74 were sequentially grown on nickel foam through two-step in-situ growth to construct a MOF-74/MIL-53 heterojunction. On this basis, we used the localized surface plasmon resonance (LSPR) effect of gold nanoparticles (Au NPs) to significantly improve the oxygen evolution reaction performance of MOF-74/MIL-53 heterojunction. Under illumation, the obtained Au-MOF-74/MIL-53 exhibits a lower overpotential of 218 mV, which is far superior to commercial catalyst. The reaction kinetics are significantly enhanced due to the lower charge transfer resistance and the higher electric double layer capacitance. We confirmed the existence of charge transfer between Au NPs and MOFs, and at the same time, the deposition of Au NPs significantly reduced the charge transfer resistance of MOF-74/MIL-53. On the basis of our work, we provide a novel MOF-based electrocatalytic nanocomposite structure for efficient water splitting. • MOF-74/MIL-53 heterojunction is synthesized by in-situ growth method. • Nanoflower-like MOF-74, with more active centers, contributes to mass transfer. • Au-MOF-74/MIL-53 exhibits much lower overpotential than commercial catalysts. • MOF coupled with plasmonic Au NPs can effectively promote water splitting. [ABSTRACT FROM AUTHOR]

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The article focuses on analyzing changes in the chemical composition of steel samples after the cooling phase. A few distinct types of samples made of St3S steel were heated in an electric resistance furnace for 1 h. The temperature in the following minutes of the furnace work was programmed to reflect the standard fire curve defined in the Eurocode in the best possible way. The box-type electric furnace was used. There were three series of samples, and each of them was cooled down in diverse ways: (a) in the water, (b) in the polymer cooling medium AQUA-QUENCH® 320, and (c) in the furnace. After that, the chemical composition of diverse types of samples with various kinds of cooling was checked. This task was realized using a laser elementary analysis microscope with the EA-300 head. The investigation allowed the authors to draw the following conclusions: the electric furnace may be used to simulate an increase in temperature with fire duration according to standard fire curve only in the phase of fully developed fire situation; the EA-300 head for laser elementary analysis allows checking of the chemical composition of investigated elements very quickly (in a few seconds). [ABSTRACT FROM AUTHOR]

Recycling lithium-ion batteries provides sustainable raw materials. Crushing and separation are necessary for extracting metals, like lithium, from batteries. Crushing a battery carries a risk of fire or explosion. Fully discharging the battery is crucial for safe production. Discharging batteries in a salt solution is a simple and cost-effective large-scale process. However, it is important to note that there is a potential risk of corrosion and loss of battery elements when batteries are immersed in a salt solution. The purpose of this study is to investigate the effectiveness of two distinct methodologies at enhancing the voltage drop of a cylindrical battery when immersed in a salt solution while preventing corrosion. These techniques involve the application of iron and copper accelerators. A 20 wt.% salt water solution was chosen based on the research of several researchers. As the current flows through the metal parts, it encounters electrical resistance and forms an electric circuit with the electrolyte solution. This interaction converts electrical energy into various physical–electrical–electrochemical phenomena, leading to a decrease in battery voltage. Research revealed that the battery can be discharged up to 100% within 4 h without causing corrosion to its components. Another point to note is that if copper conductors are used, it is possible to decrease the battery voltage by around 90% within 8 h. The gap between the copper conductor and the battery had a direct impact on the battery's discharge rate. Reducing the distance significantly increased the discharge rate, as confirmed by experimental evidence. This discharge mechanism was thoroughly described in a schematic, and, to further explain the electrochemical reaction, the Pourbaix diagram was utilized for both the Fe-Na-Cl and Cu-Na-Cl systems. Moreover, our theoretical predictions were validated through a chemical and mineralogical analysis of the precipitates that formed in the solution. [ABSTRACT FROM AUTHOR]

The work was carried out as part of a project to improve the corrosion resistance of welded joints. The optimal selection of input parameters reduces the consumption of welded material as well as the negative impact on the environment. The samples were welded by electrical resistance welding, more precisely by cross-wire welding. Electric resistance welding is a process for welding with electricity in which of high electrical resistance is used to generate heat at the contact point of the welded parts. Steel wire S235 with a diameter of 4 and 3 mm was used. The article shows the creation of the model to predict the percentage of setdown and weld strength as a function of the input parameters, welding current and welding time. The first task was to create a Design of experiments in which the process parameters or the range of input parameters are determined. The Design of the experiments was created for both wire diameters. This covers the range of parameters with which a welded joint of wires can be realised. A statistical analysis of the process follows, where it was found that for 4 and 3 mm diameter wires the percentage setdown increases with increasing welding current and time. An increase in strength as a function of welding current and welding time is also observed, but the results overlap in most cases and the range of their values is greater than that of setdown. The appearance of the weld was analysed for each sample. The visual inspection revealed seven categories of welds, which were divided into two groups, i.e. good and poor welds. All results were listed in a table with the percentage of expectation for a particular category of weld appearance. Based on the analysis, a model for determining the welding result parameters depending on the specified input parameters was developed, which can be used in practise to support the management of the electric resistance welding process. [ABSTRACT FROM AUTHOR]

Within the context of reducing the environmental impact generated by the current generation, a constant challenge for the automotive industry is to produce vehicles with the lowest possible environmental impact. In this context, in order to reduce vehicle weight and, consequently, reduce fuel consumption and emissions of gases harmful to the environment, the automotive industries have been using advanced high-strength steels. These steels make it possible to reduce thickness without losing mechanical strength and, therefore, without compromising passenger safety. Among these steels, 22MnB5 steel stands out. Among the welding processes used to weld steel sheets, electrical resistance spot welding is the most widely used joining technique in the automotive industry. The main reasons for its wide application are that it is a process in which no material addition is required and it has a high processing speed and low processing costs. In this context, this study proposes a bibliometric and systematic review of electrical resistance spot welding of 22MnB5 steel. The main objective of this study was to identify current research trends and impacts, along with a comprehensive revision. The research was carried out using the Proknow-C method. A bibliographic portfolio of 50 articles was compiled. The bibliometric analysis revealed that articles related to this topic increased substantially between 2016 and 2023 compared to previous years. The systematic evaluation of the papers in the bibliographic portfolio made it possible to identify aspects such as the research problems addressed, the materials and methodologies used, the results evaluated, and the research gaps. It was found that most of the studies focused on the weldability and mechanical performance characteristics of similar two-plate joints with an average thickness of 1.5 mm and Al-Si coatings. Finally, this article provides a comprehensive overview of the research on electric resistance spot welding of 22MnB5 steel and can provide guidance for future studies to improve the process. [ABSTRACT FROM AUTHOR]

As one of the most attractive lead-free piezoelectric ceramics, K 0.5 Na 0.5 NbO 3 (KNN) has received widespread attention and by elemental doping or forming solid solution with other components, the electrical properties can be improved dramatically. Among which, BaZrO 3 (BZ) as a most promising solid solution for modification has been introduced in KNN to induce a phase transition and thus promote the electrical performance to further meet practical applications. However, the relationship between microscopic structural characteristics and macroscopic performance is still relatively vague and need to be clarified. Hence, in this work, the structural, elastic, and electronic properties of BZ-modified KNN were investigated using the first-principle calculations. The calculated results demonstrated that BZ entered the lattice of KNN spontaneously, strengthened the Nb–O octahedron distortion and optimized the elastic properties, which are all beneficial to improving the structural asymmetry and piezoelectric response. In addition, doping Ba resulted in the shift of Fermi surface toward the conduction band and thus decreased the band gap, while doping individual Zr increased the band gap. Under the coupling action of these two atoms, KNN-BZ illustrated more denser band structure and more wider band gap, which facilitated the promotion of electrical breakdown resistance and electric polarization of KNN. This study provides theoretical insights into improving the piezoelectricity of KNN. [ABSTRACT FROM AUTHOR]

The illustrations above demonstrate that as the percentage of niobium increases, the grain size decreases, leading to an increase in the stability of transformation induced plasticity steel. This, in turn, results in improved mechanical strength. The optimal volume fraction of retained austenite for a significant transformation induced plasticity effect to occur is reported to be in the range of 10 vol. %–20 vol. %. The volume fraction of retained austenite directly determines the carbon content and grain size of the retained austenite, its two main stabilization factors. The stability of the retained austenite dictates when the strain‐induced martensite transformation (SIMT) occurs during straining of transformation induced plasticity high strength steel. Unstable retained austenite transforms almost immediately upon deformation, increasing work hardening rate and formability during the stamping process. At the appropriate stability of the retained austenite, the Strain‐Induced Martensite Transformation begins only at strain levels beyond those produced during stamping and forming, and the retained austenite is still present in the final part; it can transform into martensite in the event of a crash, providing greater crash energy absorption. The tensile strength level of micro‐alloyed transformation induced plasticity steels may exceed 1 GPa. Grain refinement mechanism is considered as the most applied mechanism used in increasing of steel strength without deterioration of ductility and toughness. Recently, it was proposed that the grain refinement could act positively on promoting the transformation induced plasticity effect of advanced high strength steel through improving the stability of retained austenite. In this research, quenching and partitioning heat treatment technique was applied to four grades of low carbon steel with different percentage of niobium. Then, the effect of niobium on grain refinement has been detected by microstructure observations. Mechanical properties and strain hardening properties of investigated steel have been determined. In addition, by using x‐ray diffraction, as well as a new electric resistance‐based sensor, it was possible to characterize the stability of the retained austenite through the plastic deformation of steel. Grain refinement by using of niobium has a great impact on promoting the stability of retained austenite against the plastic stress at the plastic deformation zone. [ABSTRACT FROM AUTHOR]

Additive manufacturing (AM) offers new possibilities in soft robotics as materials can easily be combined in multi-material designs. Proper sensing is essential for the soft actuators to interact with the surroundings successfully. By fabricating sensors through AM, sensors can be embedded directly into the components during manufacturing. This paper investigates NinjaTek Eels electrical resistance response to strain and the feasibility of using the material to create strain sensors. Strain sensors were 3D-printed out of NinjaTek Eel, a soft conductive TPU, and was tested during cyclic loading. A custom resistance–strain test rig was developed for measuring sensor behavior. The rig was calibrated for electric resistance, able to measure electric resistance as a function of strain. A parabolic response curve was observed during cyclic loading, which led to ambiguous readings. A 10-specimen validation test was conducted, evaluating the statistical variation for the first 100 loading cycles. The validation test showed that the sensor is capable of accurate and predictable readings during single load cases and cyclic loading, with the overall root mean square error being 66.9 Ω. Combining two sensors of different cross-sections gave promising results in terms of calibrating. By monitoring load cycles and strain rates, calibration can also be achieved by machine learning models by the microcontroller used to extract data. The presented work in this article explores the potential of using conductive TPUs as sensors embedded in products such as soft robotics, life monitoring of products with structural, and digital twins for live product to user feedback. [ABSTRACT FROM AUTHOR]

Magnetic tunnel junctions (MTJs) are the core elements of spintronic devices. Now, the mainstream writing operation of MTJs mainly relies on electric current with high energy dissipation, which can be greatly reduced if an electric field is used instead. In this regard, strain-mediated multiferroic heterostructure composed of MTJ and ferroelectrics are promising with the advantages of room temperature and magnetic field-free as already demonstrated by MTJ with in-plane magnetic anisotropy. However, there is no such report on the perpendicular MTJs (p-MTJs), which have been commercialized. Here, we investigate electric-field control of resistance state of MgO-based p-MTJs in multiferroic heterostructures. A remarkable and nonvolatile manipulation of resistance is demonstrated at room temperature without magnetic field assistance. Through various characterizations and micromagnetic simulation, the manipulation mechanism is uncovered. Our work provides an effective avenue for manipulating p-MTJ resistance by electric fields and is notable for high density and ultralow power spintronic devices. [ABSTRACT FROM AUTHOR]

The appearance, evolution, and proliferation of electric-vehicle motors have introduced new challenges for lubricants. The appearance of electric currents in the shafts of electric motors can dramatically change the original properties of lubricated contacts, leading to mechanism failure. Understanding and controlling this phenomenon can be advantageous for lubrication, but investigating the lubricants requires specific equipment and conditions. Therefore, in this study, we introduced a ball-on-plate reciprocating tribometer capable of applying electric voltage to the elements of the friction pair and measuring the electric contact resistance (ECR) as feedback. Mineral-based paraffin oil was used as a lubricant in this study. The coefficient of friction (COF), wear, surface morphology, and composition were analysed. It was found that high-speed ECR measurement could give valuable information regarding the lubrication conditions in reciprocating friction pairs. This study shows that even tiny currents flowing through the tribo contact can alter the lubricating conditions. Moreover, the polarity of the applied voltage is also of great importance. Applying negative voltage to the harder surface can significantly increase wear if the tribo-film is based on surface oxidation. [ABSTRACT FROM AUTHOR]

Formalin is used as a preservative in fish, as fish is a perishable product. The present study describes the development of a battery-operated portable colorimeter for the on-site determination of formalin in fish. Combining light sources of various wavelengths with an electric circuit and light dependent resistor results in a simple and cost-effective colorimeter. The gadget functions based on the light received by the light-dependent resistor, which is directly linked to the circuit board for resistance measurement using the resistance to absorbance connection and, the resistance values were converted to absorbance. The developed portable colorimeter is calibrated for the quantitative detection of formalin. The device exhibited an efficient detection of formalin at the range of 1 to 20 ppm. The portable colorimeter exhibited high accuracy and the results are promising for on-site detection of formalin in fish. [ABSTRACT FROM AUTHOR]

The study area is located in Jos South Local Government Area of Plateau State, northcentral Nigeria. Artisanal mining activity is dominant in the area with a form of sub-surface extraction of the tin through underground cavities. This research aimed at detecting subsurface cavity using 2D Electrical Resistivity Tomography (ERT) at some mining sites in the study area. Campus Omega Terra-meter was used for the survey and Wenner-Schlumberger electrode configuration was adopted with inter-electrode spacing for the various sites ranged from 2m, 5m, and 10m. Active and non-active mine sites was selected for the study and field data where interpreted using the RES2DINV software. The smoothness constrain in version formulation was adopted. In Kuru area an oval shaped high resistivity values of about 736 to 1448Om suggests an air-filled cavity and a low resistivity values of 49.1 to 33Om indicates water filled cavity while control profile shows a low resistivity values of 64.6 to 98.7Om at a depth of 31.9m as a very good aquifer, for locating a deep well. In NTA college area, three geoelectric materials namely: clay, lateritic and sandy clay were observed. The resistivity value of about 77.7Om which was lower than ressistivity value of the host country rocks of 236Om suggests a water filled cavity and lower resistivity value of 97.2Om at Profile 2 attested to water filled cavity while resistivity value of above 822Om may indicate extension of air-filled cavity at Control Profile. A high resistivity value of 1483Om characterised the top soil at a depth of about 7m at control profile in Dura-Du area and A low resistivity value 80.1 to 122 Om at depth of about 13m to 15.9m indicates fresh water. The 2D ERT geophysical method has been used succefully to identify air-filled, waterfilled and fresh water zones in the study area.. [ABSTRACT FROM AUTHOR]

Skin electroporation for drug delivery involves the application of Pulsed Electric Fields (PEFs) on the skin to disrupt its barrier function in a temporary and non-invasive manner, increasing the uptake of drugs. It represents a potential alternative to delivery methods that are invasive (e.g. injections) or limited. We have developed a drug delivery system comprising nanocomposite hydrogels which act as a reservoir for the drug and an electrode for applying electric pulses on the skin. In this study, we employed a multi-scale approach to investigate the drug delivery system on a mouse skin model, through electrical measurements, numerical modeling and fluorescence microscopy. The Electrical properties indicated a highly non-linear skin conductivity behavior and were used to fine-tune the simulations and study skin recovery after electroporation. Simulation of electric field distribution in the skin showed amplitudes in the range of reversible tissue electroporation (400–1200 V/cm), for 300 V PEF. Fluorescence microscopy revealed increased uptake of fluorescent molecules compared to the non-pulsed control. We reported two reversible electroporation domains for our configuration: (1) at 100 V PEF the first local transport regions appear in the extracellular lipids of the stratum corneum, demonstrated by a rapid increase in the skin's conductivity and an increased uptake of lucifer yellow, a small hydrophilic fluorophore and (2) at 300 V PEF, the first permeabilization of nucleated cells occurred, evidenced by the increased fluorescence of propidium iodide, a membrane-impermeable, DNA intercalating agent. Skin electroporation for transdermal drug delivery assessed by electrical measurements, numerical modeling and delivery of fluorescent molecules. [Display omitted] • Nanocomposite hydrogels function as drug reservoirs and electrodes. • Integrated electrical measurements, numerical modeling & molecule delivery. • Skin resistance drops with electric field strength. • Stratum corneum barrier disruption at 100 V. • Cell membrane permeabilization at 300 V in viable skin. [ABSTRACT FROM AUTHOR]

The effect of Al addition in ZnO varistors revealed to be the suppression of grain growth, not the lowering of the electric resistance of ZnO. This Al effect can explain the change in the E-J characteristics by the following three points. (i) The grain boundary becomes thinner and the proportion of boundary layers with a thickness of 10 nm or less increases, which enlarges the effective cross-sectional area of the tunnel current generation. (ii) The delay in densification during the sintering makes it easier for pores to remain at the grain boundary, which increases discontinuities of boundary layers between ZnO grains and increases leakage current, resulting in reduced non-ohmic properties in the low current range. (iii) Abnormal grain growth of ZnO is suppressed and the particle size becomes more uniform, which improves non-ohmic characteristics. This paper proposes a new barrier model for the conduction mechanism of ZnO varistors, based on the tunneling effect and taking into account the influences caused by microstructural inhomogeneities specific to polycrystalline ceramics, such as discontinuities in grain boundary layers and variations in ZnO grain size. [ABSTRACT FROM AUTHOR]

Polymer-derived SiAlCN ceramics as sensing materials are promising materials for wireless temperature sensors to achieve application in high-temperature harsh environments. However, limited understanding for the electric and dielectric properties of SiAlCN ceramics restricts the development of wireless sensors. Herein, the electrical and dielectric properties of polymer-derived SiAlCN ceramics pyrolyzed at different temperatures are investigated systemically. The results reveal that the electric resistance of the free-carbon phase and amorphous SiAlCN ceramic phase are comparable, however, the dielectric constant of the ceramic phase is much higher than that of the free-carbon phase. The maximum dielectric constant can reach up to 2.4E+5. Furthermore, the detailed mechanism analysis reveals that the SiAlCN ceramics with different pyrolysis temperatures all obey the same relaxation process, which is interfacial polarization and non-Debye relaxation. The deep understanding of the dielectric property of polymer-derived SiAlCN ceramics is very practical to design wireless sensors for potential applications in high-temperature and harsh environments. [ABSTRACT FROM AUTHOR]

The effects of water absorption on the electric resistivity and dielectric constant of polyimide (PI) and poly(ethylene terephthalate) (PET) were investigated, and the mechanism of deterioration in electrical insulation properties was discussed. The polyimides are poly(oxydianiline pyromellitimide) (PMDA–ODA) and poly(para-phenylene diamine biphenyltetracarboxydiimide) (BPDA–PDA). These polymer films were immersed in pure water for various immersion times at room temperature, and the water absorption ratio was evaluated. The electric resistance for these films was measured at room temperature using a high-resistance meter, and the dielectric constant at room temperature was measured using an LCR meter in a frequency range of 200 kHz to 2 MHz. The absorption ratios at equilibrium absorption for PMDA–ODA, BPDA–PDA, and PET were 2.7, 2.5, and 0.5%, respectively. The critical volume fraction of the percolation threshold of electric conductivity due to water absorption was 0.034 for both PMDA–ODA and BPDA–PDA. On the other hand, PET did not show a significant decrease in the resistivity. For both PIs and PET, the dielectric constant observed could be explained by a series model of the respective capacitances of pure water and polymer. Actually, the resistivity of samples cut from the edges of the film after water absorption was almost the same value as that in the dry state. These results suggest that the absorbed water molecules are not uniformly dispersed in the film but are localized at the edges of the film even after the absorption equilibrium has been reached. [ABSTRACT FROM AUTHOR]

Recently, hydrogen spillover based binary (HSBB) catalysts have received widespread attention due to the sufficiently utilized reaction sites. However, the specific regulation mechanism of spillover intensity is still unclear. Herein, we have fabricated oxygen vacancies enriched Ru/NiMoO4‐x to investigate the internal relationship between electron supply and mechanism of hydrogen spillover enhancement. The DFT calculations cooperate with in situ Raman spectrum to uncover that the H* spillover from NiMoO4‐x to Ru. Meanwhile, oxygen vacancies weakened the electron supply from Ru to NiMoO4‐x, which contributes to dilute the resistance of built‐in electric field (BEF) for hydrogen spillover. In addition, the higher ion concentration in electrolyte will promote the H* adsorption step obviously, which is demonstrated by in situ EIS tests. As a result, the Ru/NiMoO4‐x exhibits a low overpotential of 206 mV at 3.0 A cm−2, a small Tafel slope of 28.8 mV dec−1, and an excellent durability of 550 h at the current density of 0.5 A cm−2 for HER in 1.0 M KOH seawater. [ABSTRACT FROM AUTHOR]

Iron oxide nanomaterials are promising candidates for various electrochemical applications. However, under operating conditions high electric resistance is still limiting performance and lifetime. By incorporating the electronically conductive carbon into a nanohybrid, performance may be increased and degeneration due to delamination may be prevented, eliminating major drawbacks. For future applications, performance is an important key, but also cost-effective manufacturing suitable for scale-up must be developed. A possible approach that shows good potential for up-scale is magnetron sputtering. In this study, a systematic investigation of iron oxides produced by RF magnetron sputtering was carried out, with a focus on establishing correlations between process parameters and resulting structural properties. It was observed that increasing the process pressure was favourable with regard to porosity. Over the entire pressure range investigated, the product consisted of low-crystalline Fe3O4, as well as Fe2O3 as a minor phase. During sputtering, a high degree of graphitisation of carbon was achieved, allowing for sufficient electronic conductivity. By means of a new alternating magnetron sputtering process, highly homogeneous salt-and-pepper-type arrangements of both nanodomains, iron oxide and carbon were achieved. This nano-containment of the redox-active species in a highly conductive carbon domain improves the material's overall conductivity, while simultaneously increasing the electrochemical stability by 44%, as confirmed by cyclic voltammetry. [ABSTRACT FROM AUTHOR]

In this work, bilayer nanocoatings were designed and constructed on high-performance aromatic polysulfonamide (PSA) fibers for robust electric conduction and electromagnetic interference (EMI) shielding. More specifically, PSA fibers were first endowed with necessary electric conductivity via electroless nickel (Ni) or nickel alloy (Ni-P-B) plating. Afterward, silver electroplating was carried out to further improve the performance of the composite. The morphology, microstructure, environmental stability, mechanical properties, and EMI shielding performance of the proposed cladded fibers were thoroughly investigated to examine the effects of electrodeposition on both amorphous Ni-P-B and crystalline Ni substrates. The acquired results demonstrated that both PSA@Ni@Ag and PSA@Ni-P-B@Ag composite fibers had high environment stability, good tensile strength, low electric resistance, and outstanding EMI shielding efficiency. This indicates that they can have wide application prospects in aviation, aerospace, telecommunications, and military industries. Furthermore, the PSA@Ni-P-B@Ag fiber configuration seemed more reasonable because it exhibited smoother and denser silver surfaces as well as stronger interfacial binding, leading to lower resistance (185 mΩ cm−1) and better shielding efficiency (82.48 dB in the X-band). [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Tungsten/tungsten nitride bilayer with amorphous structure was deposited on the silicon / silicon oxide substrate by high vacuum thermal evaporation method. To investigate the thermal stability of this bilayer as a diffusion barrier layer, the Cu/W/WN/SiO2/Si multilayer was heated at different temperatures and the results were analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM) and four-point probe (FPP) methods. According to the XRD results, formation of the cupper silicide at 800° C indicates diffusion of copper from the W/WN bilayer in the Si. The formation of a Cu3Si with insulation phase leads to a sudden increase in electrical resistance (212 Ω/cm2) and will disrupt the performance of the W/WN barrier layer as a diffusion barrier. The diffusion of copper into silicon is often through undesirable grain boundaries that occur during the heating treatment of the W/WN bilayer by changing its phase from amorphous to polycrystalline and shown in X-ray diffraction results. At high temperatures, the electron microscope image has shown fracture, cracking and flaking of the surface of the copper layer, which is caused by thermal stress between the penetration barrier/copper surfaces or the volume of the layers. [ABSTRACT FROM AUTHOR]

With the expansion of the applications of sensors, requirements such as flexibility, visual transparency, and self-powering have become critical. In this work, firstly we have adopted photoetch and hierarchical (micro-nano) manufacturing techniques to fabricate a micro-scale copper grid on polyethylene terephthalate (PET). This material (Cu grid @PET) exhibits high transmittance (89% at 550 nm, only 2.7% lower than PET substrate) and low electric resistance (6.7 Ω sq−1) compared with other reports. Then, the as-fabricated Cu grid @PET composite electrode, poly-dimethylsiloxane (PDMS), and polymethyl methacrylate (PMMA) were utilized to fabricate a sandwich-like structured transparent self-powered sensor (TSPFS) with high optical transmittance of 85.5-87.5% (450 ~ 620 nm). A complete novel control method combining with sensor's electrical signal test was implemented by Dynamic Mechanical Analyzer (DMA), verifying the simulation response to space of COMSOL. Voltage signals could be also observed when the sensor was touched by fingers without receiving electric energy from external sources. Finally, the paper shows a kind of smart goggles made of the produced transparent device, exhibiting heating, antifogging, and sensing functions. [ABSTRACT FROM AUTHOR]

In this study, powder metal samples of 15x15x4 mm dimensions of Fe powders were produced at different pressures (650,850,1050 MPa). They were sintered in atmospheric environment with the help of resistance sintering method applied for the first time using electric resistance welding machine. The sintered and green densities of the powder metal samples were determined and their sinterability in the unprotected environment was examined. In addition, the effects of electric resistance heating technique on sintering were investigated by performing hardness measurement and microscopic examination of sintered samples. As a conclusion, powder metal samples were sintered successfully with the electric resistance welding technique in an unprotected environment and high-density values such as 98% were obtained. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) due to their outstanding features, such as unique electronic properties and large specific surface areas, have been intensively studied as nanoscale fillers to improve the permittivity of polymer dielectrics. However, due to the unfavourable formation of conductive channels, these CNTs-derived nanocomposites usually suffer from high dielectric loss and low breakdown strength, therefore greatly restricting their practical applications. In this work, we modified pristine multiwalled carbon nanotubes (MWCNTs) by chemical oxidation to prepare partially unzipped carbon nanotubes (PUCNTs), which not only retained excellent electrical properties but also enhanced interfacial interactions with polymers. The obtained PUCNTs/poly(vinylidene fluoride) (PVDF) nanocomposites exhibit higher permittivity and lower dielectric loss compared to raw MWCNTs added. To further alleviate the detrimental influence of conductive channels, we have designed a new class of hybrid composed of PUCNTs-decorated CaCu3Ti4O12 nanoparticles (PUCNTs-CCTO) and their PVDF-based nanocomposites. At 1 kHz, the PUCNTs-CCTO/PVDF nanocomposite filled the ternary nanocomposites also possess strong resistance to electric field failure and achieve significantly enhanced energy storage capability. With 3 vol% PUCNTs and 30 vol% CCTO, the breakdown strength of the nanocomposite can still be maintained at 125 kV mm−1 and the theoretical maximum energy density reaches to 15.5 J cm−3, which is nearly 3 times compared to neat PVDF (5.1 J cm−3). These merits of the PUCNTs-CCTO/PVDF nanocomposites suggest that the strategy proposed herein is a promising avenue for the development of dielectric materials with high energy storage capacity. [ABSTRACT FROM AUTHOR]

The present study approaches comparative research on the thermal transfer between the components of the plasticizing part of the PLA and ABS type material respectively. It can be observed that besides the fact that the temperature difference between the heating part generated with an electric resistance placed in the heated block and the nozzle is not very large, the thermal transfer is relatively linear with small temperature losses. [ABSTRACT FROM AUTHOR]

Copyright of Duzce University Journal of Science & Technology is the property of Duzce University Journal of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The surface conductivity influences the etched pattern profiles in the plasma process. In the dielectric film etching, it is vital to reduce the charging build-up, which bends the trajectory of incoming ions for highly anisotropic etching. A significant increase in surface electric conductivity of SiO2 films was observed when exposed to down-flow plasmas containing hydrogen fluoride (HF) at cryogenic temperature (−60 °C). This phenomenon can be attributed to two factors: (i) the absorption of HF and/or its compounds and (ii) the presence of H2O, which is likely originating from the etching by-product of SiO2 and/or within the reactor. Comparing the surface electric resistance of the samples treated with HF plasmas to that of CF4/H2 and C4F8/H2 plasmas, we found that HF plasma treatment enables to be approximately three and six orders of magnitude lower. By using in situ x-ray photoemission spectroscopy, it was revealed that the presence of HF and/or its compounds and H2O were absorbed on the sample surface at −60 °C. These results strongly suggest that the cryogenic plasma etching with HF-contained gases can be used to alleviate the charge build-up issues. [ABSTRACT FROM AUTHOR]

Improving the filtration efficiency of air filter materials is an ongoing research goal. This study conducted in-depth research on a new reduced graphene oxide air filter material, and the differences in its performance and conductivity durability before and after eliminating static electricity were tested and analyzed. The results showed that the filtration efficiency of the reduced graphene oxide air filter material significantly decreased after eliminating static electricity. The maximum decrease in filtration efficiency was observed at a filtration velocity of 0.8 m/s, with PM10 > PM1.0 > PM2.5. In this case, the filtration efficiency decreased by 11.8%, 7.98%, and 7.17%, respectively. The maximum difference in filtration efficiency of 0.29 μm particulates was about 12.7%. Eliminating static electricity slightly increased the resistance (2.5~15.5 Pa). In addition, the new reduced graphene oxide air filter material exhibited good conductivity and stability after continuous testing. This study provides data support for the application of subsequent electrification sterilization, reference values for multi-angle applications, and the development of new composite air filter materials. [ABSTRACT FROM AUTHOR]

Scavenging energy from aeroelastic vibrations was considered for a self-powered hybrid passive-active stall control system intended to improve the aerodynamic performance of fixed-wing micro aerial vehicles without exhausting available batteries. It was found that the passive component of the system generates intense streamwise vortices, which give rise to vortex-induced vibrations. Measured frequency response functions indicated accelerations in a wing prototype up to 0.1 g at relatively low frequencies, when it was operated at simulated flight conditions in a wind tunnel. Aiming to use this resource for additional power, a piezoelectric energy harvesting device was installed inside the wing and tuned for resonant response. Two electromechanical modeling approaches for the piezoelectric harvester were investigated, namely, an analytical model and finite elements simulations. A comparison with experimental results has shown that the latter approach is better equipped to deal with advanced designs, yielding accurate predictions in the present study. Extracted power and generated voltage were quantified as a function of the electric loading resistance. The reported data demonstrated that the proof of concept was achieved, so that a lightweight, low-consumption actuator for the active component of the stall control system can be powered by the energy of structural vibrations. [ABSTRACT FROM AUTHOR]

The emerging high-entropy oxides (HEOs) have been considered promising candidates in numerous applications due to their unique properties. Yet the dielectric properties of HEOs at high pressure remain to be disclosed. In this work, the dielectric properties of (FeCoCrMnZn) 3 O 4 at high pressures up to ∼20 GPa were systematically investigated. Combined with in-situ Raman, XRD, and impedance measurements, it is revealed that high-pressure exhibits a significant impact on the dielectric properties, even without the observed phase transition. The electric resistance, which is dominantly contributed by grain resistance, decreases exponentially with the increase of pressure. On the other hand, the relative permittivity decreases linearly with increasing pressure. In addition, the dielectric relaxation behavior of (FeCoCrMnZn) 3 O 4 at high pressure is revealed. Our results provide the experimental basis for the high-pressure effect on the dielectric properties of (FeCoCrMnZn) 3 O 4 and potential guidance for the design strategy of HEOs under extreme conditions. [ABSTRACT FROM AUTHOR]

The resistance distance R [ u , v ] between two vertices u and v of a graph G is defined as the net effective resistance between them in the electric network constructed from G by replacing each edge with a unit resistor. The resistance diameter D r (G) of G is the maximum resistance distance among all pairs of vertices of G. Given two path graphs P n = a 1 a 2 ... a n and P m = b 1 b 2 ... b m , let P n [ P m ] be the lexicographic product of P n and P m with vertex set { (a i , b j) | i = 1 , ... , n ; j = 1 , ... , m }. In [J. Appl. Math. Comput. 68 (2022) 1743–1755], Li et al. proved that for n > 10 , D r (P n [ P m ]) = R [ (a 1 , b 1) , (a n , b m) ] = R [ (a 1 , b 1) , (a n , b 1) ] = R [ (a 1 , b m) , (a n , b 1) ] = R [ (a 1 , b m) , (a n , b m) ]. In addition, they found that the result is not true for n = 2. For 3 ≤ n ≤ 10 and enough small m , they checked by computer that the result is still true. Based on their observation, they conjectured that the result is true for 3 ≤ n ≤ 10. In this paper, by combinatorial and electrical network approaches, we confirm the conjecture. [ABSTRACT FROM AUTHOR]

Evaluations of nonintrusive load monitoring (NILM) algorithms and technologies have mostly occurred in constrained, artificial environments. However, few field evaluations of NILM products have taken place in actual buildings under normal operating conditions. This paper describes a field evaluation of a state-of-the-art NILM product, tested in eight homes. The match rate metric—a technique recommended by a technical advisory group—was used to measure the NILM's success in identifying specific loads and the accuracy of the energy consumption estimates. A performance assessment protocol was also developed to address common issues with NILM mislabeling and ground-truth comparisons that have not been sufficiently addressed in past evaluations. The NILM product's estimates were compared to the submetered consumption of eight major appliances. Overall, the product had good performance in disaggregating the energy consumption of the electric water heaters, which included both electric resistance and heat-pump water heaters, but only a fair accuracy with refrigerators, dryers, and air conditioners. The performance was poor for cooking equipment, furnace fans, clothes washers, and dishwashers. Moreover, the product was often unable to detect major loads in homes. Typically, two or more appliances were not detected in a home. At least two dryers, furnace fans, and air conditioners went undetected across the eight homes. On the other hand, the dishwasher was detected in all homes where available or monitored. The key findings were qualitatively compared to those of past field evaluations. Potential areas for improvement in NILM product performance were determined along with areas where complementary technologies may be able to aid in load-disaggregation applications. [ABSTRACT FROM AUTHOR]

The paper focuses on transport properties of double perovskite Sr2FeMoO6−δ, which were studied experimentally and using First principles calculations. The strontium ferromolybdate specimens were prepared using citrate-gel method followed by compacting and thermal treatment at different regimes. The Hall effect was calculated using Quantum Espresso and Wannier90 software packages. The study conformed high sensitivity of Sr2FeMoO6 to the processing parameters such as pressure and temperature of powder compacting as well as the temperature and duration of the subsequent annealing in Ar/O2 atmosphere. The optimal regime of compacting to avoid cracking involved pressing under 4 GPa at T = 800 K. Further heat treatment of the compacted specimens in Ar/O2 atmosphere has shown that three types of electric conductivity, namely metallic, semiconducting and mixed one can be realized in the Sr2FeMoO6 specimens. The highest magnitude of magnetoresistance was found in the semiconducting specimen (about 44%), while the specimen of metallic type demonstrated magnetoresistance of about 21%. The elevated values of magnetoresistance in the semiconducting specimen were achieved due to conduction mechanism related to tunneling through intergrain dielectric layers formed by secondary SrMoO4 phase. The Hall effect was computed by constructing the Hamiltonian in the maximally-localized Wannier functions basis. Calculations of the Berry curvature, which is the origin of the high intrinsic Hall effect showed that its highest magnitudes concentrate near avoided band crossings gapped out due to spin-orbit coupling. The Hall conductivity calculated by integrating the Berry curvature over all occupied bands was found to be ~22 S/cm. [ABSTRACT FROM AUTHOR]