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To address the problem that the occurrence of large-scale blackouts in the future may cause the lack of power supply in the area and lead to the loss of power to the important places in it and a significant decrease in the living standard of the residents, this paper researches the reliability of the distribution network with electric vehicle virtual energy storage (EVVES). This paper proposes an aggregation model of EVVES applied to distribution networks, establishes the relevant models of EVVES in a virtual energy storage system (VESS) based on it, and proposes a distribution network reliability evaluation method with EVVES. Firstly, an aggregation model of EVVES is proposed to ensure that islands and important loads in the distribution network do not lose power. Secondly, the relevant models in EVVES based on the aggregation model of EVVES are studied. Finally, a distribution network reliability evaluation method with EVVES is proposed based on the traditional reliability evaluation. The improved IEEE-RBTS Bus6 is adopted as an example for reliability analysis, and the simulation results prove the validity of the model established in the paper and demonstrate that the reliability of the distribution network can be significantly improved with EVVES. [ABSTRACT FROM AUTHOR]

Flexible electrode materials refer to materials used as electrodes in electronic devices, which have characteristics such as softness, flexibility, and stretchability, and are suitable for the preparation of various flexible electronic devices. In this study, in order to optimize the problems of poor specific capacity, low conductivity, and instability of conventional flexible electrode materials, the performance and reliability of the flexible electrode materials were improved by hybridizing graphene oxide (GO) and polyaniline (PANI). In this paper, graphene oxide – polyaniline (GO-PANI) flexible electrode materials were prepared and tested for their performance using graphene and polyaniline. In the experiments, a current density of 1 A/g was selected for the constant current charge/discharge test of GO-PANI electrode materials with different graphene contents to evaluate the performance of GO-PANI electrode materials in energy storage. After the experiments, it was proved that the charge/discharge times of GO-PANI electrode materials were 1430s, 1625s, and 1495s when the graphene content was 1%, 3% and 5%, respectively, and the GO-PANI (3%) electrode material had the longest charge/discharge time. Accordingly, it can be concluded that GO-PANI (3%) electrode material had the best energy storage performance, which could realize a stable and efficient charging and discharging process, and could be used as an ideal electrode material in flexible electronic devices. The research in this paper could provide new ideas and solutions for the development of flexible electrode materials and promote the further development and application of flexible electronics technology. [ABSTRACT FROM AUTHOR]

In this paper, highly catalytically active lignin was prepared using deep eutectic solvents. The composition and microstructure properties of the prepared lignin were characterized by FE-SEM, GPC, FT-IR, and NMR. The prepared lignin was then doped into lead powder to prepare electrodes, which were electrochemically analyzed under conditions simulating zinc electrodeposition. The findings of this investigation indicate that the voltammetric charge q∗ of the lignin-doped lead-based electrode (0.6 wt%) is 0.72 C/cm2, which is twice that of the pure lead electrode (0.35 C/cm2). Lignin contains many oxygen-containing functional groups, increasing the active sites on the surface of the lead-based electrode, improving its electrochemical performance, and simultaneously reducing the oxygen evolution potential. Additionally, the oxygen evolution potential of the lignin-doped lead-based electrode (0.6 wt%) is 64 mV lower than that of the pure lead electrode. [ABSTRACT FROM AUTHOR]

In this paper, Cu-Ti alloy powder with Ti content of 2%, 2.5%, 3% and 3.5% was prepared by mechanical alloying method, and then Cu-Ti alloy powder was formed using vacuum hot pressing sintering method to prepare Cu-Ti alloy. The results show that the complete mechanical alloying time of Cu-2%Ti, Cu-2.5%Ti, Cu-3%Ti and Cu-3.5%Ti is 1h, 1h, 1.5h and 2h, respectively. Cu-Ti alloys with different Ti contents prepared by vacuum hot pressing sintering, the comprehensive properties of Cu-2.5%Ti are better, with electrical conductivity of 33.42%IACS and tensile strength of 385 MPa, which is 193.5% higher than that of pure copper. The hardness is 201.66HV, 331.1% higher than that of pure copper. [ABSTRACT FROM AUTHOR]

The aim of this paper is to study the growth mechanism and tribological behavior of electroless Ni-P plating with ultrasonic assistance on TC4 titanium alloy substrate pretreated by zincating and alkaline pre-plating process. The morphology, composition and structure of zincating, pre-plating and electroless Ni-P plating were studied to analyze its growth mechanism. The tribological behavior of electroless Ni-P plating at room temperature was investigated. The results showed that the electroless Ni-P plating had a typical cauliflower-like morphology and microcrystalline structure characteristic. And the morphology of the Ni-P plating under the action of ultrasonic was uniform, compact and smooth. Compared with the TC4 substrate, the friction coefficient and the wear scar width of the plating were reduced by approximately 35 and 70%, indicating that the Ni-P plating improved the wear resistance of TC4. The wear mechanism of the Ni-P plating was adhesive wear under the dominant of plastic deformation, and slightly abrasive wear, while the wear mechanism of TC4 was dominated by adhesive wear, accompanied by abrasive wear and oxidative wear. The ultrasonic cavitation promoted the elemental interdiffusion between the substrate and Ni-P plating resulting in the formation of the diffusion layer. The ultrasonic cavitation and mass transfer effects improve the activity of the deposition surface and the generation of atomic hydrogen, and promote the nucleation and growth of nickel on the deposition surface, as well as the diffusion of Ni2+ and H2PO2− to the deposition surface. The growth rate of the Ni-P cell-like structures in the parallel direction is greater than in the perpendicular direction. The Ni-P plating grows in a layered manner, and the growth mechanism is the heterogeneous nucleation growth mechanism. [ABSTRACT FROM AUTHOR]

In this paper, several new powder packing methods are proposed, and the COMSOL software is used to simulate the temperature distribution under different conditions. The influence of powder packing on the growth of SiC single crystal by physical vapor transport (PVT) is studied. The results show that the heat flux of the top region of the powder is increased by trapezoid graphite and graphite ring, the radial temperature gradient of the powder is reduced, which contributes to the improve the powder utilization rate. By covering the surface of the powder with a layer of porous graphite filter, the recrystallization on the surface of the powder is inhibited, the defects of carbon inclusion and thermal stress in the SiC crystal are reduced, and the growth quality and growth rate of the SiC crystal are obviously improved. The simulation results were verified by experiment, and the results agrees well with experiment. [ABSTRACT FROM AUTHOR]

Polymer-based energy storage media are widely used in electrical and electronic applications due to their high power density and excellent charge and discharge efficiency. In this paper, thermoplastic polyurethane elastomer (TPU) organic fillers were doped with polyetherimide (PEI) by the solution blending method to prepare PEI composite films with excellent energy storage properties. The effects of different TPU contents on the dielectric properties, leakage current density, and energy storage performance of the composite films were explored. The results showed that the flexible TPU fillers, which could improve the inter-chain interactions and spatial structure of PEI, reduced the chain spacing of the polymer, effectively hindered the input of charge carriers, and mitigated the electric field distortion, thus improving the insulation and dielectric properties of PEI. When the mass fraction of the added TPU elastomer reaches 0.75%, the energy storage density of the composite film reaches 11.51 J/cm3, which is 2.88 J/cm3 higher than that of the pure polyetherimide, while maintaining a high charge/discharge efficiency (87.32%), and the energy storage performance has been significantly improved under an applied electric field strength of 600 MV/m. The results show that the composite film is more efficient than the pure polyetherimide, and the energy storage performance has been significantly improved. [ABSTRACT FROM AUTHOR]

The development of micro-electronic products and the increase in demand for portable devices have driven the research of planar micro-supercapacitors (PMSCs). Flexible PMSCs have the advantages of high energy and power density, stable cycling performance and good flexibility, which makes the flexible PMSCs valuable for the research in the field of wearable electronic devices. In this paper, graphene quantum dots were selected as the electrode material for the flexible devices and PET as the flexible substrate, and the flexible PMSCs with interdigital electrode width to gap ratio of 60 μm/60 μm were prepared using modified liquid-air interface self-assembly, photolithography and oxygen plasma etching. Cyclic voltammetry, galvanostatic charge-discharge, electrochemical impedance spectroscopy and cyclic stability were performed on the devices with the bending angles of 0°, 60°, 90°, 150° and 180°, respectively, using electrochemical workstation. Redox peaks appeared in the CV curves of the devices at the very low scan rates, indicating that redox reaction occurred and pseudocapacitance effect appeared. The area capacitance, energy density and power density of the devices decreased and the charging time was longer than discharging time after the bending angle was increased. After 10,000 cycles, the cyclic stability for the five bending angles was maintained at more than 71%. In short, the larger the bending angles, the greater the impact on some performance of the devices, and when the devices were placed in non-vacuum environment for too long, some performance after bending but better. [ABSTRACT FROM AUTHOR]

In this study, a porous silicon anode material was designed to solve the problems of electrode deformation and electrical contact loss caused by volume expansion during the use of silicon anode material. Silicon-aluminum composite powder prepared by high-energy ball milling method, after Al is removed by chemical etching, Si particles show larger specific surface and porosity, and the larger pores provide a certain buffer space for the volume expansion of silicon during lithium intercalation, which can better release stress during the volume expansion, so that it has better cycle performance and higher capacity retention rate. The results showed that the porous Si anode was prepared by ball milling Si-Al powder for 12 h, and the first charge specific capacity was 2912.9 mAh/g at 200 mAh/g current density, and the coulombic efficiency was 83.91%. After 100 cycles at 400 mA/g current density, the capacity retention rate was 34.6% compared with the fourth cycle. This paper provides a new idea for the industrialization of porous silicon. [ABSTRACT FROM AUTHOR]

Growing studies that show that composite materials can improve performance by making up for the defects of ceramic membranes made of a single material. This paper prepared ZrO2/Al2O3 and TiO2/Al2O3 composite coating sols using the sol-gel technique. Ceramic membranes were prepared by dip-coating process and calcined at 350 °C calcination. The physical-chemical properties of membranes were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), N2 adsorption-desorption measurements and scanning electron microscopy (SEM). The permeability and separation performance of membranes were analyzed by doping amount, dye type and pressure difference as reference factors, and the removal rates of chemical oxygen demand (COD) and chroma in the experiment were compared. These results showed that the modified composite membranes had better microstructure, and their retention rates on the dye solutes were significantly enhanced. When the Zr/Al and Ti/Al molar ratio (nZr, nTi) of the composite membrane is 0.5, under the experimental conditions of 0.2 MPa pressure difference and 30 min filtration time, the membrane rejection rates of the four 50 mg/L dyes reached more than 80%, which was much higher than that of the Al2O3 membrane of 57.9%. At the same time, the removal rates of COD and chroma were also greatly improved. The results revealed that the use of composite materials would be required to further explore their potential to improve the performance of ceramic membranes. [ABSTRACT FROM AUTHOR]

The performance of polyurethane coating was the key factor affecting the nitrogen release characteristics of polyurethane coated urea(PCU). This paper took castor oil based PCU(PCUL and PCUH) as the research object, nitrogen release characteristics in different application environments (water and soil) and the damage of soil to the structure of polyurethane coating were discussed, when nitrogen was released from PCU, the microstructure of polyurethane coating(coatingL and coatingH) was analyzed. The results showed that the number and size of damaged holes caused by the solidification and coating-forming process of polyurethane resin solution were key factors affecting the nitrogen release rate of PCU in soil. Although wax could fill the holes as a lubricant, its degradation rate in the soil environment was faster, the swelling process of PCU caused the stretching of the coating, leading to the failure of the wax filling effect, the stretching of the coating could also cause further amplification of damaged holes.Therefore, adjusting the formula, reducing the number of damaged holes in the coating, increasing the cross-linking density of the coating, reducing the introduction of degradable components, could improve the coating performance and stabilize the nitrogen release rate. [ABSTRACT FROM AUTHOR]

Cutting tool sintering process is one of the key links in cutting tool manufacturing process. Various physical quantities change with time during cutting tool sintering. As the sintering quality of cutting tool is directly affected by these changes, it is very difficult to predict and control the sintering quality of cutting tool. Due to the complex structure of sintering equipment, it is difficult to obtain high quality and sufficient data to train the sintering quality prediction model. In this paper, the real-time condition monitoring, prediction and control of carbide cutting tool during sintering process are studied. In this study, a digital-twin model of cemented carbide cutting tool sintering furnace was established. Based on this model, the change of heat distribution characteristics in sintering furnace during sintering process is precisely described. Firstly, the paper establishes the mapping architecture of cutting tool sintering digital-twin system. Based on this architecture, a digital-twin model of heat radiation in sintering furnace is established in this paper. Based on the temperature and pressure data in the sintering furnace, the radiation heat transfer in the furnace is analyzed in order to determine the temperature change of the cutting tool sintering position. In this paper, the relationship between the temperature change of cutting tool sintering position and cutting tool grain size is studied. Based on this relationship, a rolling data-driven digital-twin prediction model for cutting tool sintering has been constructed. In this paper, cutting tool sintering temperature control driven by digital-twin system is realized based on a fuzzy control model. The validity of the digital-twin system is verified by a series of comparative experiments. The test results show that the temperature error of the system control is less than ±1 °C. It effectively improves the qualified rate of cutting tool sintering. [ABSTRACT FROM AUTHOR]

In this paper, a terahertz metamaterial refractive index sensor based on electromagnetically induced transparency effect is proposed. The unit structure is composed of a closed square ring and a split circular ring. The transmission spectrum of the sensor generates sharp transparent peak at around 0.615 THz. Geometric factors on transmittance were simulated and analyzed, including the size of the opening ring, the distance between the two rings, the circular ring radius, and the refractive index of the tested object. Subsequently, the sensing performance of the device was also studied with a refractive index sensitivity of 3.68 µm/RIU. [ABSTRACT FROM AUTHOR]

To reduce the battery performance attenuation of electric vehicles under high and low temperature conditions, it is necessary to design a battery thermal management system to avoid unnecessary energy consumption, while improving safety and endurance. In this paper, a battery thermal management system is established. Considering the time-delay and nonlinear characteristics of the battery system itself, the control strategy is designed based on multivariate model predictive control (MPC), and the simulation is carried out based on MATLAB. Simulation results show that MPC controller can save energy and improve efficiency, and have a better control effect than PID control. [ABSTRACT FROM AUTHOR]

In the plating process, the addition of additives can improve the quality of the plated layer. Suitable additives can make the plated layer more resistant to corrosion while obtaining a flat and bright plated layer. In this paper, the effects of four types of additives on the corrosion resistance of electroplated zinc–nickel alloy plating were investigated, and the process conditions such as current density and plating time were determined by Hull tank experiments and small tank experiments. The effects of the content of various additives and different additives on the corrosion resistance of the plating layer were investigated, and the optimal additives were the compound combination of BH-A and BH-B at 6 mL/L each. Under the same plating process conditions, the effect of adding suitable additives and not adding additives on the corrosion resistance of the plated layer was investigated. The findings revealed that, in comparison to the plating solution sans additives, the integration of appropriate additives not only enhanced the deposited layer's corrosion resistance but also led to a decrease in grain size, increased uniformity, density, and achieved a higher degree of flatness. The results indicate that, in contrast to the plating solution without additives, the inclusion of suitable additives not only enhances the corrosion resistance of the resulting plated layer but also generates a smaller grain size, uniformity, density, and higher flatness in the deposited layer. [ABSTRACT FROM AUTHOR]

With the growing demand for new energy batteries and the increasing need for battery thermal management, the heat dissipation performance requirements of water coolers are also becoming more stringent. This research paper concentrates on the study of high energy efficiency of the water chiller system. Based on two aspects of structure and algorithm, refined calculation and selection are carried out.It introduces a linkage control logic based on three adjustable main components (water pump, fan, and compressor). The findings demonstrate that the water chiller with a refined design offers a safer and more stable water cooling system with reduced power consumption. [ABSTRACT FROM AUTHOR]

As one of the most important electrical equipment in power system, the stable operation of transformer is the key factor to ensure the safety of power grid system. Winding deformation is the most common fault of transformer, which will seriously affect the reliable operation of the whole power system. Therefore, the detection of transformer winding deformation is of great significance to prevent transformer accidents. In order to further improve the reliability of transformer winding deformation detection, this paper proposes a transformer winding deformation detection method based on oscillation wave method. Firstly, the equivalent circuit model of transformer winding is established, and the transformer winding fault is simulated by changing the inductance and capacitance parameters in the model, and the law between the change of oscillation wave curve and the change of related performance indexes and equivalent parameters is obtained. Finally, the field test verification is carried out on a 10 kV transformer in the laboratory. The results show that the oscillation wave method can diagnose the transformer winding deformation and can be used for the actual transformer winding deformation detection. [ABSTRACT FROM AUTHOR]

In China, titanium dioxide production is still based on sulfuric acid process which suffers from high energy consumption, serious pollution and long process. For solves the traditional problems, cleaner production is an effective way for the high-quality development and comprehensive green transformation of sulfate titanium dioxide industry. Taking a titanium dioxide company in Panzhihua as an example, this paper expounds the exploration and practice of utilizing advanced process equipment to transform the original specific process and improve the clean production process and equipment. The company has upgraded the continuous acidolysis process, VCE (Vapor-Condense-Evaporate) crystallization process and MVR (Mechanical Vapor Recompression) concentration process for the three core sections with serious waste and energy consumption, and effectively coupled with the other original sections. Through the analysis of production operation, the new process significantly improves the comprehensive resources utilization efficiency of titanium, sulfur and iron, improves the working environment of labors, and reduces the energy consumption, the amount of three wastes and the production cost. Company in the gradual realization of cleaner production, made beneficial exploration. [ABSTRACT FROM AUTHOR]

Germanium oxide is an important optical dielectric material with high application value in integrated optical systems. In this paper, the potential energy curves (PECs) of the ground state (Χ1∑+) and three electron low-excited states (a3Σ+, A1Π and B3Π) of GeO molecules (a3Σ+, A1Π and B3Π) were calculated by using the Dunning's related harmonic basis function and large basis group aug-cc-pwCV5Z with diffusion groups. The analytical potential energy function was obtained by fitting the Murrell-Sorbie function (MS) and the least squares method, and the fitting error was very small, indicating that the obtained analytical potential energy function could reproduce the interaction between atoms in GeO molecules. The spectral constants calculated by using the obtained analytical potential energy function are in good agreement with the experimental values, indicating the reliability and accuracy of the obtained analytical potential energy function. [ABSTRACT FROM AUTHOR]

This paper proposes an output predictive control design for the endovascular magnetic resonance imaging (MRI)-guided nanorobots in the presence of actuator and sensor delays. The nanorobot is modeled considering the effects of hydrodynamic drag force, apparent weight, and magnetic motive force. Using feedback linearization approach, the state feedback control is designed. To physically implement the predicted states in the state feedback control, the high-gain predictor is constructed. The performance recovery property of the output feedback using the high-gain predictor is achieved. The numerical simulation demonstrates the effectiveness of the designed controllers and the performance recovery property of the designed high-gain predictor. [ABSTRACT FROM AUTHOR]

Vibration assisted welding (VAW) has emerged as a successful replacement for heat treatments of arc welds to refine grain, reduce residual stresses and distortions and thus to improve its mechanical properties. In this paper, mechanical VAW would be applied on the 8 mm thickness Q345B steel CO2/MAG filler welding, and the filler materials are solid core welding wire and flux-cored welding wire, respectively. The results show that: with the application of vibration, the proeutectoid ferrite in the weld area becomes finer, and the dendrites in the columnar crystals become significantly finer and more evenly distributed. The microhardness value of the weld zone in the welded joint with vibration is higher than that in the welded joint without vibration. The tensile strength of the welded joint increased from 502.5 MPa to 551.0 MPa at the motor speed of 2700 r/min when using solid core welding wire, increase nearly 10%. While, the tensile strength was deteriorated after the motor speed increased to 3600 r/min, which decreased to only 412 MPa, and the decreasement reached 25% comparing with the motor speed of 2700 r/min. During the VAW, the tensile strength and impact value of the welded joints fabricated by flux-cored welding wire are obviously better than that fabricated by solid core welding wire. [ABSTRACT FROM AUTHOR]

ZnAlO thin films with different Al concentrations were prepared on glass and silicon substrates by Magnetron sputtering in this paper. Scanning electron microscopy (SEM), X-ray diffraction (XRD), spectrometer and other instruments were used to analyze the surface morphology, microstructure, transmittance and Raman spectrum of the films. The results showed that trace Al doping significantly increased the surface morphology and size of ZnAlO thin films; The low doped ZnAlO thin film exhibits a good preferred orientation. As the Al doping concentration increases, the main growth direction of the crystal gradually shifts from (101) to (103), and the grain size decreases with the increase of doping concentration during low doping; When the wavelength of ZnAlO film is less than 330 nm, the transmittance of the film is almost zero; When the wavelength is greater than 350 nm, the transmittance of the thin film decreases with the increase of Al doping concentration, and there is a blue shift trend with the increase of Al concentration. When the wavelength is between 420-900nm, the average transmittance of ZnAlO thin film can reach over 90%, and the transmission performance is good; The ZnAlO thin films all have structural characteristic peaks of wurtzite with a frequency of about 437 cm−1, and the Raman peak position does not move with the increase of Al concentration. [ABSTRACT FROM AUTHOR]

The spark-plasma sintering of ceramics based on the cubic pyrochlore phase in the system Bi2O3-ZnO-Nb2O5 is reported for the first time. It is shown that the use of spark-plasma sintering in the manufacture of (Bi1.5Zn0.5)2(Zn0.5Nb1.5)2O7 ceramics makes it possible to obtain a high density, a homogeneous microstructure, and high dielectric parameters (almost 30% higher compared to conventional ceramic technology). The paper discusses the features of microstructure formation and the optimization of spark plasma sintering regimes. [ABSTRACT FROM AUTHOR]

This paper shows the results of experimental studies of the influence of oxygen pressure under pulsed laser deposition on the electrophysical parameters of BaTiO3 nanocrystalline films. The elemental composition of BaTiO3 films obtained at different pressures (1×10−5 Torr (vacuum) and 1×10−2 Torr (oxygen)) was studied by XPS methods. Based on the obtained results, the energy-efficient memristor structures based on BaTiO3 nanocrystalline films were proposed. It was found that 20-nm-thick BaTiO3 films based memristive structure exhibited stable resistive switching effect: HRL/LRS∼10 for 100000 cycles. The results obtained can be used to fabricate energy-efficient memristive structures. [ABSTRACT FROM AUTHOR]

Hydroxyapatite (HAP) structures with cationic substitutions are studied. Paper presents results obtained using DFT calculations for Mg/Ca substitutions in HAP depending on Mg concentration. Data obtained showed agreement with the experiment: the lattice parameters decreased with increase in Mg concentration. A symmetry violation was found upon the Mg/Ca substitution in the Ca2 position compared to the Ca1 position, due to OH distortion and the Mg-O pair shift relative to OH channel axis. The change in piezoelectric coefficients upon these Mg/Ca2 substitutions was higher by a factor of 1.5 than those of Mg/Ca1. The corresponding changes was in the IR spectrum. [ABSTRACT FROM AUTHOR]

At present, coal mine tunneling technology is developing in the direction of intelligence and unmanned. The piezoelectric vibration energy harvester can convert the vibration energy generated by the cutting part of roadheader into electrical energy and realize the energy self-sufficiency of the low-power wireless sensor. In practical applications, the vibration frequency of the cutting part of roadheader is different, and the working condition is complex, resulting in the energy recovery efficiency of the vibration energy harvester is not ideal. In order to improve its adaptability and reliability, a separated excitation broadband piezoelectric vibration energy harvester is proposed in this paper. [ABSTRACT FROM AUTHOR]

To find out the effect of the rare earth doping element Holmium (Ho) on CuInS2 thin films, various studies have been carried out and the results have been reported in this paper. The PL study shows that intensity of doped film is more than undoped film. The PL emission peak appears at 570–580 nm. SEM images of CIS:Ho (4 ml) film shows agglomeration on the surface. Both synthesized film of CuInS2 appears to be amorphous in nature with chalcopyrite structure as clear from XRD. Hall measurement and optical studies were also performed. [ABSTRACT FROM AUTHOR]

In this paper, a composite excitation method is used to optimize the design of an existing cantilevered cylindrical ultrasonic motor to avoid vibration interference. Modal and transient simulation analysis of the stator structure was carried out by the finite element method. Optimized stator structure is simpler than the original motor. Simulation analysis results show that the circumferential amplitude is increased by more than 35% with 55.7% reduction in ceramic usage. [ABSTRACT FROM AUTHOR]

At present, coal mine tunneling technology is developing in the direction of intelligence and unmanned. The piezoelectric vibration energy harvester can convert the vibration energy generated by the cutting part of roadheader into electrical energy and realize the energy self-sufficiency of the low-power wireless sensor. In practical applications, the vibration frequency of the cutting part of roadheader is different, and the working condition is complex, resulting in the energy recovery efficiency of the vibration energy harvester is not ideal. In order to improve its adaptability and reliability, a separated excitation broadband piezoelectric vibration energy harvester is proposed in this paper. [ABSTRACT FROM AUTHOR]

To find out the effect of the rare earth doping element Holmium (Ho) on CuInS2 thin films, various studies have been carried out and the results have been reported in this paper. The PL study shows that intensity of doped film is more than undoped film. The PL emission peak appears at 570–580 nm. SEM images of CIS:Ho (4 ml) film shows agglomeration on the surface. Both synthesized film of CuInS2 appears to be amorphous in nature with chalcopyrite structure as clear from XRD. Hall measurement and optical studies were also performed. [ABSTRACT FROM AUTHOR]

In this paper, detailed studies of effect of small amount of manganese substitution (at the zirconium site) on the structural, micro-structural, and electrical characteristics of lead zirconate titanate of Pb(Zr0.35–xMnxTi0.65)O3;x = 0, 0.02, 0.06, 0.10 (PZMT)) have been reported. The materials were prepared by using standard ceramic technology. The formation of the compounds and their basic crystal data have been studied through X-ray diffraction (XRD) method. The crystallite size and lattice strain of the compounds, evaluated from Scherrer's and Hall Williamson (H-W) equations, is found to be in the range of 40–50 nm and 11 × 10−4 to 50 × 10−4, respectively. Microstructures of different magnifications, revealing the surface nature of the compounds, have been recorded by field emission scanning electron microscope (FESEM). Effect of Mn+4 ions on electrical behavior (electrical impedance (Z*), electrical modulus (M*), conduction and relaxation phenomenon) of PZMT systems, over wide range of temperature and frequency, has been studied. [ABSTRACT FROM AUTHOR]

Rare earth yttrium substituted lithium ferrites Li0.5Zn0.1Ti0.1YxFe2.3–xO4 with nominal composition x = 0.00 to 0.10 in steps of 0.02 was prepared by the conventional ceramic method. The samples were sintered at 1050 °C for 6 h using resistive conventional heating. X-ray diffraction (XRD) patterns confirmed the formation of a single phase with a spinel structure. FTIR studies also confirmed the tetrahedral and octahedral metal-oxygen bonding of the spinel structure. Structural parameters like density, lattice constant, and crystallite size, site distances, bond length distances were measured from XRD data. The crystallite size reduces while the density increased with the progressive substitution of Y3+ ions. The Fe3+ ions at the A and the B sites mainly contributes to the electromagnetic properties of ferrites. Y3+ ions preferably entering the B sites can significantly interfere with the conduction mechanism of lithium ferrites. The objective of the present work is to find out the effect of Y3+ substitution on the structural and electrical conduction response Li-Zn-Ti ferrites. The DC resistivity initially is found to increase for concentration x = 0.04 and then decrease with further substitution. The study of the temperature dependence of DC resistivity depicts two types of conduction mechanisms in the range studied. The results obtained are analyzed and presented in the paper. [ABSTRACT FROM AUTHOR]

Potassium sodium niobate (KNN) is an environmentally compatible piezoelectric material for substituting harmful lead-based ceramics. KNN-based ceramics have excellent piezoelectric properties with high Curie temperature. But, KNN faces difficulties during the processing like volatilization of alkali elements, chemical inhomogeneity, low densification, etc. The objective of this research is to investigate the impact of certain metal oxides additions like ZnO and MnO2 as sintering aids to solve the problems of the preparation and hence study the structural and electric properties of K0.5N0.5NbO3 (KNN) ceramics. ZnO and MnO2 added potassium sodium niobate, K0.5N0.5NbO3 was prepared by using the ceramic method. The prepared samples were sintered at 1000 °C for 2h conventionally. The structural properties of the ceramics have been analyzed by using X-Ray Diffractometer. The study demonstrates the formation of the orthorhombic-symmetric perovskite phase in all the prepared samples. The microstructural behavior of the ceramics has been characterized by techniques such as scanning electron microscopy (SEM) and compositional properties were studied by energy dispersive x-ray (EDAX). The effects of metal oxide additions on the electronic properties such as dielectric constant, dielectric loss, impedance properties, Nyquist plot, etc., were studied. The results have been analyzed and discussed in the paper. [ABSTRACT FROM AUTHOR]

Through a typical solid-state reaction followed by planetary ball milling, ABO3 structured perovskite Bi0.5Na0.5ZrO3 (BNZ) was employed as an additive to create the lead-free piezoceramic composite having compositional formula K0.47Na0.47Li0.06NbO3+(x)Bi0.5Na0.5ZrO3 where x = 0.0 wt% to 0.5 wt%. The prepared composites were characterized with the help of XRD, SEM, and FTIR. The XRD results indicated manifestation of morphotropic phase boundary (MPB), i.e. orthorhombic-tetragonal (O-T) phase boundary, for 0.4 wt% and 0.5 wt%. The SEM pictures revealed the microstructural properties of grain-grain size distribution and the average grain size of the composites. The elemental composition examination using EDAX revealed no foreign element contamination. The FTIR examination verified the development of perovskite, indicating that the BNZ has correctly fused into the KNLN matrix. The DC resistivity (ρdc) behavior was determined from IV and IR curves measured at room temperature together with varied temperature line up from 30 °C to 150 °C and a high dc resistivity ρdc of order ≈ 109 Ω cm was obtained for all the ceramics. The results have been analyzed and the mechanism pertaining to the results has been discussed in the paper. Thus the main idea was to develop a lead-free piezoceramic composite by incorporating Bi0.5Na0.5ZrO3 as an additive and investigating its effect on the above mentioned properties of the composite material. [ABSTRACT FROM AUTHOR]