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The paper studies domain orientation processes in ferroelectric ceramics induced by a weak dc electric field. The field dependences of the complex elastic, electromechanical, and piezoelectric parameters of the PZT type ferroelectric ceramics were measured using the piezoelectric resonance analysis method for the radial extensional mode of thin piezoceramic disks. The method used ensures high accuracy in determining the complex constants of piezoelectric materials, as well as their changes under external influences. A physical interpretation of the results is proposed. [ABSTRACT FROM AUTHOR]

The ferroelectric, lead-free perovskite sodium bismuth titanate-barium titanate (BNT-BT) has excellent electrical performance and is now recognized as a possible alternative material for lead zirconate titanate (PZT). It can be doped with some active elements to form a solid solution with a morphotropic phase boundary (MPB), where the solid solution has high dielectric properties and high energy storage performance. In this paper, the research results of BNT-BLT, BNT-BLZT, BNT-BSLZT, BNTBMNLT and BNT-BST-KNN ceramic materials are summarized, and the influence of their doping mode on the phase structure and electrical properties are analyzed. The study found a rhombohedral and tetragonal phase coexistence region, where the tolerance factor value of ceramics is between 0.7530 and 0.7803. Moreover, the energy storage density of antiferroelectric ceramics increases with the expansion of the MPB region and is affected by the dielectric constant. [ABSTRACT FROM AUTHOR]

The present paper is devoted to the study on the dielectric properties and microstructure of samples of multicomponent ceramics of the PZT system with various Curie temperatures. The coexistence of two ferroelectric phases is shown. They behave differently during the poling process. The temperature dependence of the dielectric permittivity of pooled samples of compositions near the morphotropic phase boundary exhibits anomalies below the Curie temperature. [ABSTRACT FROM AUTHOR]

In this paper, a percussive piezoelectric energy harvester device is proposed, which can better obtain the vibration energy in the low frequency. Through the construction of the experimental prototype and the experimental test, the results show that the output power is affected by the acceleration and the thickness of the percussive beam. When the free end mass of the piezoelectric beam is 3 g and the excitation frequency is 12.8 Hz, the maximum output power of the energy harvester is 316.8 μW. It is 2.3 times of the maximum output power of the energy harvester without mass. [ABSTRACT FROM AUTHOR]

In this paper, the ferroelectric (FE) properties of 20-nm-thick Hf0.5Zr0.5O2 films deposited by an atomic layer deposition technique by using O3 or H2O as an oxygen source were studied. For both oxygen source, the Hf0.5Zr0.5O2 films exhibited the formation of a non-centrosymmetric orthorhombic phase, which was responsible for the FE behavior. However, it was shown that the H2O-based Hf0.5Zr0.5O2 films were more unsuitable for hydrogen from H2O than the O3-based Hf0.5Zr0.5O2 films, which reduced the FE polarization and increased the leakage behavior. The results indicated that the use of O3 as an oxygen source in the ALD process has potential for the fabrication of FE Hf0.5Zr0.5O2 films for next generation memory applications. [ABSTRACT FROM AUTHOR]

In the present paper, orange–red BaMoO4:Sm3+ phosphor was synthesized by high-temperature solid-phase method. The morphology, elemental composition, crystal structure, photoluminescence performance, and charge compensation mechanism of BaMoO4:Sm3+ were investigated. Results indicated that the BaMoO4:Sm3+ phosphor particles were spherical-like in shape with approximate particle size of 2 μm and contained Ba, Mo, O, and Sm elements. The Rietveld-refinement of X-ray diffraction profile of BaMoO4:Sm3+ was consistent with a tetragonal lattice. Under 404 nm excitation of light, BaMoO4:Sm3+ phosphor showed the strongest emission peak at 649 nm and emitted an orange–red light. When the orange–red phosphor was packaged with a 395 nm UV chip and tested, the color coordinates were (0.3109, 0.3626) under a current of 60 mA, the color rendering index Ra = 81.5, and the color temperature was 6385 K. These results indicated that BaMoO4:Sm3+ red phosphor is suitable as a red light component in WLEDs and has potential practical applications. [ABSTRACT FROM AUTHOR]

This paper proposes a geometric nonlinear analytical model of a vortex-induced energy harvester (VIEH) with variable beam width in order to improve the output performance. The analytic method is adopted to establish the geometric nonlinear model of VIEH. Based on the geometric nonlinear analytical model, the beam structure is then optimized to improve the output. The results show that the harvested power and average power density within a specific resistance range can be increased through the beam width variation of the VIEH. Nonlinear hardening behaviors can be observed in the outputs varied by the flow velocity of a VIEH with variable beam width. [ABSTRACT FROM AUTHOR]

Recent years have seen a considerable research interest in multiferroic materials for their potential application as sensors and actuators. However, the scarcity of these materials in a single phase and the weak coupling of their ferroic components have directed research toward multiferroic heterostructures. These systems operate by coupling the magnetic and electric properties of two materials, generally ferromagnetic and ferroelectric, via strain. In this paper, thin films have been grown by chemical solution deposition (CSD) using spin coating technique using rotations peed of 4500 rpm and time of 50 s and dried at 120○C for 20 min. The optical, dielectric, magnetic, ferroelectric, ferromagnetic, and piezoelectric properties of thin films have been investigated by Uv- Visible spectrophotometer (300-2500) nm, X-Ray Diffraction (XRD), Vibrating Sample Magnetometer (VSM), Transmission Electron Microscope (TEM), and Scanning Electron Microscope (SEM) respectively. PZT/CFO thin films deposited at different temperatures from 400 °C, 500 °C and 600 °C. The as-deposited PZT/CFO show week piezoelectricity and the effective piezoelectric coefficient d33 because the materials deposited on the films not only the PZT layer but also the CFO layer, which decreases the piezoelectricity of these films. PZT/CFO Films were then recorded to enhance all physical properties (dielectric, optical, structural, surface morphology, and magnetic properties) as the sintering temperature increased. The images of a thin film before and after treatment with Nd-YAG, which have Power from 10 mw to 5300 mw, Pulse width: 7 ns pulsed laser, Repetition Rate: 10 HZ, and wavelength spectrum in (IR, Vis) laser beam indicate that sample prepared before treated has a lot of porous and agglomeration which decreases after treatment. [ABSTRACT FROM AUTHOR]

This paper presents the application of an ordinary sintering process for 3 h in air to fabricate highly dense (Na0.52K0.44Li0.04)(Nb0.88Sb0.08Ta0.04)O3 (NKN-LST) ceramics with excellent piezoelectric properties at a lower sintering temperature through the use of excess Na2O as a sintering aid. The effects of sintering temperature in the range 940–1100 °C and Na2O addition in the range of 0 to 3.0 mol% on the density, sintering behavior, microstructure, dielectric and piezoelectric properties of the NKN-LST ceramics are investigated. Analysis reveals that NKN-LST ceramics samples sintered at 1020 °C for 3 h in air with 1.5 mol% excess Na2O achieve the highest electromechanical coupling factor and piezoelectric coefficient values of 0.45 and 364 pC/N, respectively. [ABSTRACT FROM AUTHOR]

The climbing phenomenon of fluid driven by surface acoustic wave was discovered, and its climbing characteristic was experimentally studied. A steel ball was fixed on an YX-128° LiNbO3 piezoelectric substrate by help of polydimethylsiloxane at the bottom of the steel ball. The fluid was forced by the acoustic streaming force and the resistance from the steel ball, leading to climbing the steel ball. The climbing characteristic was investigated using red ink solution. Results show that 3 µL red ink solution can climb the top of the steel ball with 2 mm diameter at 28.7 dBm electric signal power. [ABSTRACT FROM AUTHOR]

Piezoelectric vibration acceleration sensor is widely used in our life. If there is a big electromagnetic pulse in the environment, the electromagnetic pulse will be coupled into the circuits through power cords and data cords. The electromagnetic pulse protection circuits of power cords and data cords are researched in this paper. The piezoresistor and transient suppression tube are used as transient components in the protection circuits. Through simulating, the optimized protection circuit is found. The method of group comparison is proposed in this paper. The simulation and experimental results show that the protection circuits proposed in this paper can protect the sensor very well. [ABSTRACT FROM AUTHOR]

Molybdenum disulfide (MoS2) is a typical two-dimensional material, which is widely used in many fields because of its excellent electrical and optical properties. In recent years, the high-quality growth of MoS2 has attracted more and more attention from researchers. Many studies have reported a two-step method for the production of MoS2 by pre-deposition of molybdenum (Mo) source and then vulcanization, which is cumbersome and time-consuming, and the preparation temperature is mostly above 800 °C, increasing energy consumption and experimental risk. In this paper, S source and Mo source can be distinguished by double temperature zone tube furnace to prepare MoS2 material in one-step method. The temperatures of S and Mo sources were designed separately, and the effect of each temperature on the quality of MoS2 was investigated. And the monolayer MoS2 with high crystalline quality was obtained at a S source temperature of 165 °C and a Mo source temperature of 680 °C. We produce MoS2 in one-step method at low temperature, which provides a reference for the synthesis of high-quality monolayer MoS2. [ABSTRACT FROM AUTHOR]

Macroscopic modeling of ferroelectric properties refers usually to Landau-Ginzburg-Devonshire theory. This paper questions the meaningfulness of this term, discussing contributions of the three authors in the title to what is supposed to be a theory. The limitations of every contribution are analysed. In the main text and, to more extent in the , the Landau theory is presented from an unusual perspective starting from simple mechanical models of spontaneous symmetry breaking and finishing by the Ising model. The aim of the presentation is to emphasize along with the qualitative breakthroughs the approximate character of macroscopic modeling associated with the above three authors. [ABSTRACT FROM AUTHOR]

The electrochemical performances of microsupercapacitors depend on the electrode materials. And graphene quantum dots are a very ideal electrode materials. In particular, nitrogen or oxygen doping is beneficial to enhance the Faraday reaction kinetics and improve the interfacial wettability of the carbon electrode and electrolyte solution. In this paper, nitrogen and oxygen co-doped graphene quantum dots were used as electrode materials and the electrode film was prepared by a modified liquid-air interface self-assembly method. The microsupercapacitors had high electrochemical characteristics including the area capacitance which was 98 μF cm−2, the energy density which was 0.014 μWh cm−2, the power density which was 51.07 μW cm−2 and the excellent time constant which was 0.12 ms. Meanwhile, the capacitance retention rate was 97.3% after 10,000 cycles. [ABSTRACT FROM AUTHOR]

Strength quality can reflect the physical quality, strength forging plays a positive role to maintain a strong body and abundant energy. The transmission system of traditional fitness equipment, such as electric treadmill and bicycle fitness device, are difficult to achieve the force training effect of simulating the rapid change of resistance like wind gust change and slope change automatically according to the pre-programmed curve changes in real time or speed. Combined with the current situation and existing problems of fitness equipment at home and abroad, this paper develops a self-generating power generation and electromagnetic damping control system that does not require external power supply, also has intelligent charge and discharge function, which can adjust the resistance output in real time. The system, which takes permanent magnetic synchronous generator as the resistance source, can replace the complex mechanical resistance structure and some electric resistance structure, and is widely used in the fitness equipment such as treadmill and bicycle trainer. [ABSTRACT FROM AUTHOR]

In this paper, potassium sodium niobate lead-free piezoelectric thin films were prepared by sol-gel method. The electric domain structure and optical band gap of the thin films were regulated by doping Mn. It is found that Mn doping increases the grain size and density of KNNLT piezoelectric film surface. In addition, Mn doping can regulate the electric domain of thin films. Increasing Mn doping concentration can regulate the size and distribution of electric domain, and the ratio of 71° electric domain increases with the increase of doping concentration. The results show that the optical band gap decreases gradually with the increase of doping amount when the annealing temperature is 650 °C. The lowest optical band gap reaches 3.426 eV, and is lower than the undoped KNNLT films. [ABSTRACT FROM AUTHOR]

This paper reports a low-cost method for the preparation of AgInS2 thin films on conductive glass. The AgInS2 thin films were prepared by electrodeposition method after sulfurization at 400 °C for 1 h in N2 atmosphere. AgInS2 was successfully prepared using nitrate, sodium citrate and sodium thiosulfate as raw materials. The experimental results show that a good AgInS2 film can be obtained when the deposition potential is −1.0 V and the deposition time is 30 min. The AgInS2 film with chalcopyrite and tetragonal phase structure can be prepared under different deposition temperatures and different pH conditions, and the pH has a greater influence on the phase of AgInS2. The composition of the AgInS2 film prepared by sulfurization after electrodeposition basically accords with the stoichiometric ratio. [ABSTRACT FROM AUTHOR]

This paper studies the application of zinc oxide semiconductor nanomaterials in the printing process, including (1) photolithography technology (2) microcontact technology (3) screen printing (4) inkjet writing technology commonly used in daily life. Among them, the screen printing and lithography technology are analyzed in detail, and the use process and specific process of the two methods are introduced. In the process of preparing zinc oxide into ink, not only the method and process are introduced in detail, but also chemical formulas and examples are listed. In the experiment on ZnO, it can be objectively analyzed that the evaporation characteristics of the organic solvent of the ZnO semiconductor nanomaterials determine the characteristics of the carrier, which leads to the uneven quality of the formed printed film. If the solvent evaporates quickly, the paint will gradually evaporate the water in it during printing to increase the viscosity of the slurry. [ABSTRACT FROM AUTHOR]

As one of the new high-performance products, the ferroelectric liquid crystal light valve has entered people's daily lives and has been widely used. Because of its excellent characteristics, it is widely used in various aspects such as industry and commerce. This paper adopts an experimental analysis method and data analysis method, and aims to break through the existing image acquisition methods by studying ferroelectric liquid crystal light valve film and high-speed image acquisition system, and develop an image acquisition system with faster speed and high-quality performance. According to the experimental results, the system can meet the functional requirements and technical indicators proposed by the design and can operate safely and stably, achieving the expected effect of the design. [ABSTRACT FROM AUTHOR]

Compared with traditional secondary batteries such as lithium-ion batteries, lithium-sulfur batteries have a higher theoretical specific capacity (1675 mAh/g) and energy density (2600 Wh/kg), so they are regarded as the most promising one of the lithium batteries. However, it also has problems such as volume expansion during the reaction, poor conductivity of sulfur, serious "shuttle effect" caused by poly-sulfides, and slow electrochemical reaction kinetics. In this paper, a two-step hydrothermal method was used to synthesize CNTs-MoS2/SnO2 composite materials. We assembled CNTs/MoS2 materials, CNTs/SnO2 materials and CNTs-MoS2/SnO2 composite materials into batteries and tested their electrochemical performance. The experimental results show that the CNTs-MoS2/SnO2 composite material has a more significant catalytic effect and a stronger adsorption capacity. The first-lap discharge specific capacity reaches 1369.9 mAh/g at a rate of 0.1 C, and the Coulomb efficiency can reach more than 98%after 150 cycles at 0.2 C. Its excellent performance is due to the synergistic inter-action of p-type semiconductor metal sulfide MoS2 and n-type semiconductor metal oxide SnO2, and the p-n heterojunction interface formed by the two promotes ion and the transmission rate of electrons. [ABSTRACT FROM AUTHOR]

Titanium alloy Ti-5553 has the advantages of high strength and corrosion resistance, but its high cutting temperature and chemical activity in the machining process reduce its surface integrity. In this paper, the effect of surface integrity on fatigue life is analyzed in terms of surface morphology, microstructure, and residual stresses through liquid nitrogen cryogenic and dry cutting Ti-5553 experiments. The results show that the surface roughness parameter Ra and Sq both show a trend of decreasing and then increasing under the same cutting parameters. Under cryogenic cutting effectively improves surface integrity and extends the fatigue life of the specimen. [ABSTRACT FROM AUTHOR]

Friedel's salt is a common hydrate of cement concrete in chloride environment, and the change of its performance will affect the performance of cement paste and the safety of concrete structure. In order to study the properties and morphological characteristics of Friedel's salt, Friedel's salt is prepared by reaction of C3A with chlorine salt and chemical synthesis in this paper. The expansibility and stability of Friedel's salt are studied by XRD, SEM, TG-DTG and FTIR. The results show that the higher the curing temperature is, the faster the reaction rate is, the expansion degree is 0.3 and the density is 2.087 g/cm3. Friedel's salt is more stable in alkaline environment, and the greater the pH value is, the more stable the Friedel's salt is. Under dry heat curing, Friedel's salt is gradually decomposed with the increase of temperature, and the Friedel's salt prepared by C3A and chlorine salt is completely decomposed at 500 °C, and the Friedel's salt prepared by chemical method is completely decomposed at 600 °C. Under damp heat curing, Friedel's salt is gradually decomposed with the increase of temperature, and it is not completely decomposed at 100 °C. [ABSTRACT FROM AUTHOR]

Based on the theory of elasticity, the bending behavior of piezoelectric cantilever with gradient property for piezoelectric parameter g31is studied. By use of Airy stress function method, the solution of cantilever subjected to a couple and an electric field is obtained. The results obtained in present paper are compared with that from both experiment and other analytical models based on BaTiO3-ceramics. It is found that the tip deflection of cantilever obtained in present papers agrees well with the result of N-morph cantilever when the number N gets to∞. Present paper also gives a theoretical demonstration that all the mechanical stresses will be vanishing in FGM actuators. Finally addressed in present paper is a method of parameter identification. [ABSTRACT FROM AUTHOR]

In this paper, a CSVO3 phosphor for white LED has been successfully prepared by solid-state synthesis and has been characterized. The CsVO3 was simulated by Materials Studio software based on density functional theory (DFT). The results show that the CsVO3 sample has a direct optical transition with band gap energy of 3.143 eV. Under ultraviolet excitation in the range of 300–390 nm, the emission spectrum of CsVO3 phosphors ranges from 400 to 700 nm, and its peak emission spectrum is near 492 nm, and shows yellow color fluorescence emission. These results indicate that CsVO3 phosphor can be used as a promising white phosphor for white LED. [ABSTRACT FROM AUTHOR]

Owing to high hardness and high brittleness of SiC ceramic, it is difficult to machine into structural ceramic components with desired surface quality and dimensional accuracy. In this paper, a method of polishing SiC ceramic by underwater femtosecond laser was proposed. The influence of laser frequency and pulse energy on surface morphologies, 3 D profiles, depth and surface roughness of polished SiC ceramics during underwater femtosecond laser processing was investigated in detail. The experimental results indicated that the removal depth during underwater polishing increased and then decreased with the increase of laser frequency and pulse energy. The surface roughness increased as laser frequency increased. The surface roughness decreased and then increased with the increase of pulse energy. Through laser parameter optimization, a high quality polished surface without cracks, pits and debris redopesition was obtained under laser frequency of 40 kHz and pulse energy of 40 μJ. At this point, the average removal depth of 32.19 μm and the average surface roughness of 0.72 μm were obtained. The proposed method in this paper significantly improve surface finishment and higher dimensional accuracy of the machined SiC ceramic components. [ABSTRACT FROM AUTHOR]

Poly(vinylidene fluoride) (PVDF) has been a kind of particularly attractive piezoelectric materials for its excellent piezoelectric property. It has been proven that the piezoelectric property of PVDF can be improved by electrospinning. Recently, the technical innovations on the multiple aspects of preparing electrospun PVDF nanofibers such as collecting equipment and the pretreatment emerged in endlessly. The article introduces electrospinning briefly firstly and the second part of the paper introduces some recent research on the preparation of electrospun PVDF nanofibers. The researches about promising applications using electrospun PVDF nanofibers involve biomedicine, sensors, and energy harvesting due to its flexibility, biocompatibility, and outstanding performance. The last part of the paper reviews the typical research. [ABSTRACT FROM AUTHOR]

A three dimensional model for a nano/microfabrications of silicon on nothing (SON) structure based on phase field model has been presented. The temperature induces morphological evolution of silicon substrate has been introduced and suggested as a great possibility for the evolution dynamics. Phase field model is employed to present the morphological evolution of silicon. The numerical simulations represent an efficient verification on the experimental work. The performed work could present a detailed process of the cavity formed in the silicon substrate under high temperature. The mechanism for making the cavity in the silicon substrate is the shape changes, which is caused by surface diffusion and driven by the minimization of their surface energy. The aim of this paper is providing a reliable fabrication process of silicon substrate in high temperature, and control the fabrication process when the annealing is performed. The performed simulation results are well consistent with the experimental works. [ABSTRACT FROM PUBLISHER]

In this paper, the shaft parts of failed machine tools were treated by laser cladding, and the shaft surface of 45# steel matrix was repaired. The microstructure, hardness and corrosion resistance of the cladding layer and quenched phase transformation zone were analyzed by metallographic microscope, Vickers microhardness tester, and friction and wear tester. The laser cladding layer was tested by friction and wear tester. The results showed that the friction coefficient of laser cladding layer was only 0.58, and it fluctuated slightly. The corrosion resistance of laser cladding layer was obviously increased. [ABSTRACT FROM AUTHOR]

Passivation is carried out on the basis of low chromium or no chromium. This paper has prepared a nontoxic passivation agent suitable for building door and window hardware. Its formula is sodium molybdate, cobalt nitrate, phytic acid, sodium citrate, phosphoric acid sodium. The content of each component was determined by the single variable factor experiment method, the corrosion resistance was measured by electrochemical workstation, the surface morphology and coating thickness of the passive film were observed and analyzed by JSM-6380LA scanning electron microscope (SEM), and the German Brook D8 Advance diffractometer was used. The composition of the passivation film was analyzed, and the corrosion resistance of the passivation film was tested in a salt spray test box. Finally, the optimal formula of the chromium-free blue and white passivation agent was sodium molybdate 40 g/L, sodium phosphate 20 g/L, sodium citrate. 15 g/L, phytic acid 10 ml/L, cobalt nitrate 1.5 g/L, PH value 1-2, passivation time 8–20 s. The prepared passivation used this nontoxic passivation agent can reaches 72 h in the neutral salt spray test. This work provides a new idea for the development of nontoxic passivation agent, and it has potential commercial value [ABSTRACT FROM AUTHOR]

With the application of higher and higher power density IC in power driver circuits, an efficient modeling method of thermal design and heat dissipation is desired. In this paper, the printed circuit board (PCB) heat dissipation without heat-sink is discussed. Firstly, the thermal resistance of PCB thermal via array is analytically modeled. Then, the optimal via diameter and number are found in a limited area for minimum thermal resistance. Secondly, the radial temperature distribution is analyzed and a method of designing a proper copper pad for heat dissipation under the design power is posed. Finally, computational fluid dynamics (CFD) simulations are developed to verify the posed model and method. [ABSTRACT FROM AUTHOR]

CFRP/Ti laminated materials are widely used in key parts of aircraft such as skin and wing, but the common problem of the two kinds of difficult to machine materials is particularly prominent tool wear, which seriously affects the quality of parts. In this paper, an experimental study was carried out on the milling of CFRP/Ti laminates with diamond coating unit edge tool. By combining theoretical analysis and experiment, the surface morphology and the change law of cutting force of CFRP/Ti laminates under different tool wear conditions were obtained. The results show that abrasive wear is the main mechanism in CFRP cutting zone, while adhesive wear is the main wear mechanism in the titanium alloy cutting zone, accompanied by the mixture of abrasive, oxidation and diffusion. With the tool wear aggravating, the milling force gradually increases and accompanied by irregular fluctuations. [ABSTRACT FROM AUTHOR]

Energy issues have always been one of the most concerned issues in the world. To solve the problem of building energy consumption, the future development of building energy-saving projects is more meaningful. This article aims to study the application of the parameter tester based on ferroelectric ceramics in building energy-saving projects. This paper proposes to use the orthogonal test method to elaborate and accurately calculate the energy-saving projects of green buildings and calculate the annual energy-saving rate and load rate of green buildings, to achieve real building energy conservation and reduce energy consumption. The comparative analysis method is used to conduct strict calculation and analysis of the four specific energy-saving systems in the enclosure structure, such as doors and windows, external wall insulation, roof, and sunshading, to more clarify the advantages and disadvantages of each component in the enclosure structure place. According to the experimental data of this article, under the premise that the energy saving rate of this article fully meets the national requirements exceeds 50%, in this model, in terms of the full life cycle cost, the cost of using the worst solution can be reduced by 614,900 yuan compared with the cost of the best solution. [ABSTRACT FROM AUTHOR]

The LiFePO4 with olivine structure has become one of the most popular cathode materials for lithium-ion batteries due to its absolute superiority of safety, environment-friendly, inexpensive. In this paper, Fe3(PO4)2 and Li2CO3 were used as raw materials, meanwhile graphite powder or glucose as reducing agent to prepare the LiFePO4 cathode materials via carbothermal reduction method. The effects of molar ratio of lithium to iron, calcination temperature, calcination time, C% and the different C resource on the phase, morphology and electrochemical properties of the products were investigated. The experimental results showed that when the molar ratio of LiFePO4 was 1.05, the calcination temperature at 750 °C for 3 h, and graphite powder or glucose content 5%, the pure olivine structure LiFePO4 sample was obtained, the particle size of which was about 2 ∼ 5 μm with good dispersibility. The prepared sample was assembled as CR2032 Button Battery for electrochemical performance. The charge-discharge capacity was close to the theoretical capacity of 170mAh/g, the efficiency was more than 99% and high-rate capacity retention was maintained at 96.5%, respectively. The overall electrochemical performance of LiFePO4 was excellent. [ABSTRACT FROM AUTHOR]

In this paper, the projection method, the stereographic method and the spherical map method are used to calculate the spatial angle of the parts with the oblique hole in the numerical control machining center. At the same time, the calculation principle and method of the spatial double deflection angle hole system in the numerical control machining center are studied.The projection method is used to analyze the spatial angle relation of Φ10 holes in milling. V spherical method and H spherical method are used to calculate the positioning angle and the orientation angle. The spatial angle of a valve body part in milling Φ12 space inclined hole is calculated by using the stereographic method, and the positioning angle and the orientation angle are calculated by using the V spherical graph method and the H spherical graph method.The calculation results show that the spatial angles obtained by the above methods are the same, which verifies the correctness and the feasibility of the calculation method. [ABSTRACT FROM AUTHOR]

In this paper, nanostructured Cu2O thin films were prepared on glass substrates by magnetron sputtering. The effects of the O2/Ar ratio and sputtering power on the preparation of Cu2O thin films were investigated. In order to verify its morphology and phase, we use scanning electron microscope and X-ray diffraction to test. The first principle is used to calculate the crystal structure of Cu2O, and the optical properties and electronic structure of Cu2O are calculated. Our structure shows that Cu2O is a direct band gap material with 2.144 eV. It has good absorption capacity in the ultraviolet region and high transmittance in the visible region, which is consistent with the experimental results. It can be used as an ideal electrode material for solar cells. [ABSTRACT FROM AUTHOR]

In this paper, we provide the adsorption behavior of lysozyme on the inverse colloidal crystal (ICC) membrane under different parameters (such as temperature, pH value, adsorption time). Besides, this also studied lysozyme adsorption behavior by changing the Hydroxyethyl methacrylate (HEMA) ratio of the ICC membrane. Furthermore, we found that ICC membranes containing Hydroxyethyl methacrylate have significantly improved lysozyme adsorption than ICC membranes without Hydroxyethyl methacrylate. With the increasing lysozyme concentration, the ICC membrane containing 50% HEMA showed an excellent selective adsorption effect. At the same time, we describe the adsorption mechanism of lysozyme on the ICC membrane containing HEMA. Finally, after ten adsorption-desorption cycles on the ICC membrane, the membranes adsorption effect on lysozyme has not significantly decreased. [ABSTRACT FROM AUTHOR]

Nanometer cemented carbide has a wide range of applications and prospects in the fields of machinery, metallurgy and industrial mold, based on its excellent mechanical performance. During the fabrication of WC-Co cemented carbide, the grains have high potential to grow up, how to manufacture the nano-cemented carbides with excellent comprehensive mechanical properties remains challenging. This paper demonstrates that the WC-10Co nano-cemented carbide combining with carbon nanotubes can realize enhanced the mechanical properties of nanomaterials. Ultra nanometer indentation tests are conducted to detect the hardness and elastic modulus of the nano-WC-10Co-CNT composite material. The key figure of merit of the CNT composite nano-material and its ability to refine the grains and to enhance the comprehensive performance are proved. We also envision that when the doping amount of CNT reaches to 0.7%, the performance of the nano CNT composite cemented carbide will degrade due to the exiting of free carbon. [ABSTRACT FROM AUTHOR]

The instantaneous cutting contact relationship between tool and workpiece is changing with the change of curvature profile of open blade impeller. This leads to a strong nonlinear characteristic of the dynamic cutting load change during the machining of this type of parts, which affects the machining accuracy of the blade. This paper proposes a method to predict the machining error of ball-end milling under dynamic load. This method considers the influence of the curvature change of blade profile. Based on the analysis of the instantaneous cutting contact of complex surface in ball-end milling, a prediction model of the instantaneous undeformed cutting thickness of ball-end milling under the influence of surface curvature changes is constructed. Based on this model, the correction of the prediction model of machining complex surface milling force is realized. The prediction of the machining error when the complex surface is thin-walled impeller is processed under dynamic load. Finally, the effectiveness and accuracy of the method are verified through ball-end milling experiments. The research can provide guidance for the control and compensation of milling machining errors of complex-shaped thin-walled open blade. [ABSTRACT FROM AUTHOR]

The paper presents the results of studying the polarization properties of solid solutions ceramics, including sodium and calcium niobates at room temperature and frequency f = 50 Hz. Three classification regions of the dielectric hysteresis loops formation were identified. The nature of observed effects formations was determined. [ABSTRACT FROM AUTHOR]

The paper presents a calculation of doping concentration profile in a two-layer barium titanate film, one of the layers of which contains lanthanum impurity. The theoretically predicted distributions were experimentally verified. Influence of the doping profile on the magnitude of the electrocaloric (EC) response of ferroelectric films is assessed by numerical simulation. It is demonstrated that at the same La concentration, the magnitude of the EC effect can change by 40% due to the distribution of the lanthanum concentration in the structure. The results obtained allow optimizing the technological process to ensure the required characteristics of ferroelectric thin films. [ABSTRACT FROM AUTHOR]

This paper presents a study of microstructure and dielectric properties of solid solutions of (1-х)BiFeO3 − x/2 PbFe1/2Nb1/2O3 − x/2 PbFe2/3W1/3O3 system with x = 0.05 ÷ 0.50 using X-ray diffraction analysis. Phase diagram of the studied system at room temperature is obtained. Critical influence of oxygen defects and liquid phase on formation of structure and microstructure of the samples is detected. Relaxor nature ε′′/ε0 for the studied solid solutions is demonstrated dealing with occurrence of Maxwell-Wagner's relaxation due to movement of oxygen vacancies. [ABSTRACT FROM AUTHOR]

The paper provides information on the growth of SrTiO3/Si (001) (STO/Si) and 0.5BiFeO3–0.5PbFe0.5Nb0.5O3/SrTiO3/Si (001) (BFO-PFN/STO/Si) composite heterostructures. BFO–PFN/STO/Si composite thin films were deposited on Si substrate by RF-cathode sputtering using STO as buffer layer for textured growth. The use of STO enhanced the orientation for the perovskite phase growth of the BFO–PFN films, which was confirmed by XRD. It was shown that the BFO–PFN layer in the BFO–PFN/STO/Si heterostructures suffered a strain and thus their physical properties were modified. The optical properties of the STO/Si pseudo-substrate were studied in detail. [ABSTRACT FROM AUTHOR]

This paper presents the results of a study of the dielectric response in single crystals of barium strontium niobate doped with thulium of various concentrations. It is shown that the dielectric permittivity increases with increasing concentration of thulium. For as-grown samples the dispersion of the permittivity is observed in the frequency region of 106 Hz. The dependence is not observed for the samples polarized under DC field. For all the samples studied, the switched polarization increases and the coercive field decreases under action of an AC field. [ABSTRACT FROM AUTHOR]

In this paper, thin films are considered within the framework of the Ising model with a depolarizing field. In the existing works, the depolarizing field is considered to be proportional to the polarization, but it is not suitable for polydomain films. According to our approach, the depolarizing field energy is calculated as the difference between the energy of dipole-dipole interactions in a bulk sample and a thin film. Stripe domains with neutral and charged walls can appear in the considered model. We also studied domain structures arising in films of different thicknesses with increasing temperature and depolarizing field value. [ABSTRACT FROM AUTHOR]

Piezoelectric wafer active sensors (PWAS) are lightweight and inexpensive transducers made from ferroelectric piezoceramic wafers attached to safety-critical structure. PWAS transducers enable a large class of structural health monitoring (SHM) applications. The focus of this paper is on the predictive modeling of structurally-attached PWAS. After a brief introduction, the paper reviews the PWAS-based SHM principles. Then, it follows with a discussion of shear-lag analysis, the transfer matrix method approach and the investigation of power and energy transduction between PWAS and structure. Finally, the paper presents a multi-physics finite element (MP-FEM) simulation. The paper ends with summary and conclusion. [ABSTRACT FROM AUTHOR]

Energy harvesting from piezoelectric is proved to be a viable technology to source low power electronic devices. In this paper, piezoelectric energy harvester is designed such that the energy is harvested by utilizing the switching of the MOSFET in DC-DC converter, which becomes an integral part of modern industrial equipment. Energy harvesting is realized by piezoelectric and converse effect of piezoelectric material. The harvester is designed to have transmitter and receiver piezoelectric separated by metal plate, connected across the drain and source terminals of the MOSFET. The performance of the harvester is experimentally evaluated with boost converter for supercapacitor storage. [ABSTRACT FROM AUTHOR]

With the wide application of direct current transmission, it is necessary to inspect and test the high-voltage DC electric field strength during maintenance of transmission lines and DC converter stations to ensure the safety of workers.This paper designs a DC high voltage electroscope based on a vibrating capacitance sensor. The design of the vibration and capacitance sensor probe, the probe signal processing circuit design and the signal processing module of the power inspection device were studied.The fabricated vibrating capacitance sensor probe is placed in the DC electrostatic field. Then we analyzed the experimental data. The voltage value measured by the sensor is linearly proportional to the DC electrostatic field strength value, indicating that the measurement principle and measurement method are reasonable. Finally, according to the measured DC voltage signal can know whether the charged body is charged to achieve the effect of the electroscope. [ABSTRACT FROM AUTHOR]

Untreated leaded waste glasses will pollute the environment which can release lead ions. Which is can be solidified into the concrete after being broken. Then the pollution problems could be solved, and the concrete slabs would radiation protection specialty of be increased. In this paper, the entire process of the crushing of waste glass which contains lead and its addition technique in concrete could be designed and researched after the FEM and EDEM analysis. A new double toothed roll crusher was studied base on the traditional crashers in this paper, and its work mechanism, structure and technique characteristics were introduced to crash the glass into the specified size. The morphological structure and optical transparence of the particles could be watched through a wide depth of field microscope. [ABSTRACT FROM AUTHOR]

The electric forces are the main factor responsible for the characteristic jet path and stretching in electrospinning. The distribution of the electric field determines the quality of the electrospinning. In this paper, a glass flywheel nozzle is designed, and a ring electrode and a capacitor are added between the nozzle and the receiving plate. Theoretical calculations prove the feasibility of the design. The finite element analysis software COMSOL Multiphysics5.0 is used for electric field simulation. The effect of the voltage across the ring electrode and capacitor on the electric field was studied. It is found that when the ring electrode is connected to 10 kV voltage and the voltage across the capacitor is 5 kV, the uniformity of the electric field is significantly improved, which provides a reference for the future optimization of the electrostatic spinning electric field. [ABSTRACT FROM AUTHOR]

In this paper, thick film antiferroelectric ceramics (1-x)(Pb0.97La0.02)(Zr0.46Sn0.48Ti0.06)O3-xH3BO3 ((1-x)PLZST-xH3BO3, x = 0–0.025) were prepared by solid state sintering and tape-casting method. The effects of boron-doping on the microstructure, dielectric properties and energy storage properties of (1-x)PLZST-xH3BO3 ceramics were investigated. Appropriate boron-doping can improve the stability of antiferroelectric phase, delay phase transition and increase saturation polarization strength. Compared with the undoped PLZST thick films, the maximum polarization intensity increased by 1.9 times and the residual polarization decreased by 37%. When x = 0.020, the maximum recoverable energy storage density is 2.74 J/cm3, and the energy storage efficiency is 88.12%. [ABSTRACT FROM AUTHOR]