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The paper presents some general patterns of the temperature behavior of thermodepolarization currents, dielectric permittivity and conductivity of dielectric materials containing water molecules or hydrogen bonds – crystallohydrates, polyelectrolytes, and biopolymers. The results indicate that the anomalies of these properties are observed at 4, 20, 35, 46, 65–76°С, which are "threshold points" of water, when its structure changes abruptly. The observed anomalies are probably due to a change in the proton energy at a transition to an excited level in the double-well potential at heating, while the equilibrium of the system is achieved by slow stepwise heating. [ABSTRACT FROM AUTHOR]

This paper reports a novel piezoelectric energy harvester incorporated on a waistbelt for power generation from waist movements. The device is composed of multiple piezoelectric disks in 3 D-printed encapsulations and rectifying circuity, which are connected to a battery for energy storage. The harvester was simulated and tested through different body activities. Measured open circuit voltages up to 19 V, μW-level AC power generation, and energy storage test results clearly demonstrate that the energy harvester presented here can effectively convert waist movements into electrical power, store energy in a battery, and support the batteries of wearable electronic devices for extended operations. [ABSTRACT FROM AUTHOR]

This paper presents a six-band metamaterial absorber (MMA). It has a three-layer structure: metal-FR-4-metal. The simulation results demonstrate that there are six distinct absorption peaks at 8.94, 16.47, 19.35, 23.61, 27.03 and 27.42 GHz and absorption rates are 99.68%, 99.52%, 99.46%, 99.92%, 99.89% and 96.22%, respectively. Through the analysis of the effects of structure parameters, then optimized them. Then the electric field and surface current distribution has been studied under the normal incident of TE and TM waves. The simulation results illustrate that it is polarization-insensitive and has simple structure and high absorption rate, so it can be applied in electromagnetic stealth, bolometers, sensor and so on. [ABSTRACT FROM AUTHOR]

In this paper, iterative optimization is carried out within the allowable range of mismatch of the crystal lattice, and the density of states, energy band, differential charge density and effective mass of the cell-electrode interface are calculated and analyzed. It is proposed to improve the application of ferroelectric LiNbO3-based electric-optic modulators with a better choice of electrodes, and can provide a carrier-transfer basis for the ferroelectric materials. And the calculation of the interface offered selection for the new materials electrode, to improve the efficiency in the electric-optic transfer and the storage efficiency in the future. [ABSTRACT FROM AUTHOR]

Bent-core liquid crystal (LC) is used to dope the (4-cyano-4′-pentylbiphenyl) liquid crystal (5CB). The polarizing microscopy results show that 5CB and LC exhibit Nematic (N) and Banana-Shaped (B1) mesophases, respectively. In this paper, we use dielectric spectroscopy to determine the dielectric properties of the 1% LC doped with 5CB liquid crystal. The dielectric parameters of these materials have been determined by different applied voltage. In this respect, dielectric properties of 5CB + 1% LC have been compared with 5CB. The dielectrical anisotropy of 5CB and 5CB + 1% LC liquid crystal composite changes from the positive dielectric anisotropy to negative with the frequency of the applied voltage. The critical frequency fc values of dielectrical anisotropy for 5CB and 5CB + 1% LC composite were found to be 688 and 534 kHz, respectively. The real (ε′) and imaginary components (ε′′) of dielectric constant have been calculated by capacitance method. It has been also determined that adding LC to 5CB decreases the voltage dependent dielectric strength and increases threshold voltages. [ABSTRACT FROM AUTHOR]

Magnetoelectric (ME) nanorobotic structures has application in targeted biological cell manipulation and optimized drug delivery. An approximate 70 nm diameter of Cobalt Ferrite- Barium Titanate, ferromagnetic core and piezoelectric shell is studied in context to its ability for nanoelectroporation in biological cell. Physics modeling is performed using COMSOL Multiphysics and quantitative analysis is used to understand the impact of applied magnetic field on the generated mechanical waves and electric pulses. The focus of this paper is to compliment relevant in vitro studies with ME nanorobots and to understand real-time changes in magnetostriction, piezoelectric and nanoelectroporation. The design of the magnetic navigation system with the relevant parameters to generate the required flux density for magnetostriction is discussed extensively. Assuming strong coupling between the core-shell, the 20 nm piezoelectric barium titanate contributes to electric pulsation that alters the membrane permeability leading to increased conductivity. This real time theoretical analysis provides scope for relevant clinical studies for engineering swarm of nm range robotic composites for targeted cell manipulation. [ABSTRACT FROM AUTHOR]

This paper presents the design and development of manual frequency tuneable energy harvester. The energy harvester consists of beam, piezoelectric materials, proof mass, charging circuit, storage device and enclosure box. The design of beam and proof mass was made using the output of previous work and other parts were designed in this work. The energy harvester was developed based on the design and placed into the enclosure box. The fabricated model was tested to know the performance of energy harvester by analysing the output voltage, current, power and charging time of the battery. The distance of proof mass was varied from the fixed end of the cantilever beam to tune the frequency of energy harvester. From the experiment, it was found that the proof mass of energy harvester at 115 mm produced 88.77% more power compared to the proof mass placed at 85 mm from the fixed end. The operating range of energy harvester is about 5 Hz to 30 Hz. The proof mass placed at a distance of 155 mm from the fixed end charge the 60 mAh battery at 65.14% faster compared to the proof mass placed at 85 mm from the fixed end. [ABSTRACT FROM AUTHOR]

This paper presents a direction adaptive energy harvester to scavenge multiple wind directions. A pair of rotatable hinges were fixed on a rotation axis to realize the orientation adaptive. The transverse bending vibration of piezoelectric beam induced by vortex shedding was converted into electricity while the change of relative position between magnets and coils output electricity too. The prototype of the energy harvester was fabricated and experiments were carried out. The harvester exhibited that the optimal power of piezoelectric and electromagnetic generation are, respectively, 5.19 mW and 0.32 mW in the wind speed range of 3.8 m/s to 6.4 m/s. [ABSTRACT FROM AUTHOR]

In this paper, Co-doped Na3V2−xCox(PO4)2F3(x = 0,0.1,0.5,0.7) sodium ion battery anode material was prepared by one-step hydrothermal method, and Na3V1.5Co0.5(PO4)2F3 anode material coated with graphene was also prepared. It is confirmed that moderate Co2+ doping can improve the electrochemical performance of NVPF. Among all samples, Na3V1.5Co0.5(PO4)2F3@Graphene shows the best rate and cycle performance. It exhibits the highest specific capacity of 91.5 and 48.8 mAh/g at 1C, respectively when x = 0.5, after coating graphene, the charge-discharge specific capacities of 1C cycle are 128.2 mAh/g and 63.5 mAh/g for the first time, and 62.2 mAh/g and 45.1 mAh/g for 45 weeks.The performance results show that the excellent electrochemical performance of Na3V1.5Co0.5(PO4)2F3@Graphene can be attributed to the increase in electronic conductivity and ion diffusion coefficient. [ABSTRACT FROM AUTHOR]

The paper reports on the piezoelectric performance, electromechanical coupling and related energy-harvesting figures of merit of three forms of 1–2–2 composites based on domain-engineered single crystals. The effect of the single-crystal piezoelectric properties and elastic properties of the laminar polymer matrix on the appropriate figures of merit of the composite is studied. The main active components of the studied composites are [0 0 1]-poled perovskite-type single crystals with chemical compositions: 0.92Pb(Zn1/3Nb2/3)O3–0.08PbTiO3, 0.67Pb(Mg1/3Nb2/3)O3–0.33PbTiO3 and [Lix(K1−yNay)1−x](Nb1−zTaz)O3: Mn, where x = 0.06, y = 0.1–0.3, z = 0.07–0.17, and the level of Mn doping is 0.25 mol. %. Examples of non-monotonic volume-fraction dependences of the piezoelectric properties, figures of merit and anisotropy factors are analysed. New diagrams are first built to demonstrate the volume-fraction regions where a large anisotropy of the piezoelectric coefficients d3j* and electromechanical coupling factors k3j* is achieved, and where energy-harvesting figures of merit of the composite are at least five times larger than analogous parameters of single-crystal components. The studied 1–2–2 composites are of interest as anisotropic materials with high piezoelectric sensitivity and large figures of merit which are important for sensor, energy-harvesting and related applications. [ABSTRACT FROM AUTHOR]

In this paper, a high frequency, wide band, horizontal omnidirectional ultrasonic transducer for piezoelectric composite tubes was developed. The sensing element of the ultrasonic transducer was a tri-ring stacking round tube structure. This structure is designed to increase the opening angle of the wave speed and widen the bandwidth. The test results of the ultrasonic transducer when it works in water are as follows: the central frequency is about 300 kHz, the maximum sending voltage response is 158 dB, the working bandwidth is 111.52 kHz, and the maximum receiving sensitivity is −208 dB. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the structural, the electronic and the magnetic properties of the equiatomic quaternary Heusler alloy CoRuMnGe using the first-principle calculations. In fact, we apply the DFT method under Quantum Espresso package. For this purpose, we have examined the structural properties in order to determine the stability of the three configurations of this alloy: type I, type II and type III. Our calculations confirmed that the configuration of type I is the most stable one for the equiatomic quaternary Heusler alloy CoRuMnGe. Consequently, we have studied the electronic, magnetic properties and exchange coupling interactions only for the stable configuration. Also, we have illustrated the nearly half metallic behavior of this alloy, and deduced the rule Slater Pauling. On the other hand, following the mean-field approximation (MFA), we computed the Curie temperature value T C MFA = 446.53 K for the studied compound. [ABSTRACT FROM AUTHOR]

Lead free piezo materials are becoming popular as the world is conscious about toxicity of PbO present in PZT. As a result, lot of R&D efforts are made in last two decades to find out suitable lead free piezo ceramics as effective as PZT. There are many lead free piezo systems explored. Among them, BZT-BCT is more promising due to its high piezoelectric coefficients. This system is well researched by modifying its structure with a large number of dopants. In this paper, an effort has been made to review the effect of various dopants on electrical properties of BCT-BZT systems. [ABSTRACT FROM AUTHOR]

In this research paper, we report the dielectric and electric investigation of series of dielectric ceramics samples with structural formula Ba2-xRe4+2x/3Ti8O24(where Re = Sm and La and x = 0.0, 0.2, 0.4 and 0.6). The dielectric parameters (i.e. dielectric constant and loss tangent) and ac conductivity are measured with impedance analyzer. This paper is presented to compare the effect of samarium and lanthanum doping on the properties of barium titanate. The research work concludes that lanthanum doping has more favorable effect on the properties. This paper also presents impedance analysis and V-I characteristics of all the samples. This is concluded that these properties are strongly dependent on frequency, temperature and composition. The investigation reports almost constant value of dielectric constant and very low loss tangent at lower temperatures. [ABSTRACT FROM PUBLISHER]

Optical second harmonic generation (SHG), which is sensitive to the symmetry breaking, provides a powerful experimental technique for investigation of ferroic materials, i.e. ferroelectrics, magnetics, and multiferroics. A far-field confocal microscopy provides three-dimensional imaging of an order parameter of ferroics with a spatial resolution up to diffraction limit of a probing wavelength. In this paper, we discuss general important consideration regarding SHG microscopy and show new imaging techniques for ferroelectric and magnetic domains and switching, bio-inspired ferroelectrics, as well as femtosecond laser annealed ferroelectric microstructures. [ABSTRACT FROM PUBLISHER]

In a semi-review paper, the fundamentals of the vibronic (pseudo Jahn-Teller) theory of ferroelectricity in perovskite crystals of ABO3 type, its main achievements and significant applications, are given. The theory is derived from first principles. First, the pseudo Jahn-Teller effect (PJTE) is introduced and shown to be the only source of polar instability that triggers the spontaneous polarization of the crystal. The driving force of the PJTE is added covalency by distortion, which is essentially of local (chemical) origin. Then, the earlier more qualitative, but physical transparent results in application of the PJTE theory to ABO3 perovskites are presented, followed by the rigorous formulation in terms of Greens' functions theory. The form of the adiabatic potential energy surface (APES) for the metal B sites with eight equivalent minima, obtained analytically, is confirmed by DFT calculations, and its parameter numerical values were estimated for BaTiO3. It explains the occurrence of the three ferroelectric and one paraelectric phases, and order-disorder transitions between them as due to temperature dependent gradual overcome of the consecutive barriers between its eight equivalent minima. The theoretical treatment of the phase transitions is carried out in the mean-field approximation yielding near-to-experimental Curie temperatures. An important further development of this theory was reached more recently, for the first time revealing the role of spin in ferroelectric polarization of perovskites with the electronic dn configuration of the B ion. It was shown that, subject to the PJTE, not only d0 configurations may be unstable to produce ferroelectricity ("the d0 mystery"), but some other specific dn configurations with unpaired electrons may be dipolar active too, the crystal being thus both magnetic and ferroelectric (multiferroic). The necessary conditions for such multiferroicity are formulated for the whole n = 0,1,...10 variety of perovskites, and it is shown to be different in the two (or more) possible spin arrangements of the same ion, high-spin or low-spin for n = 3, 4, ...7. In conditions of spin crossover this leads to a magnetic-ferroelectric crossover that can be manipulated by external perturbations, including electric magnetization, already realized experimentally. A novel chapter is opened in application of the vibronic PJTE theory to important problems of materials science by analyzing the interaction of the ferroelectric perovskites with external perturbations. For the paraelectric phase of BaTiO3 with local dynamic-polar instability, any external electric field, strain, or stress violates the equivalency of the eight minima of the APES, quenching the polar dynamics, thus contributing an orientational polarization (like in polar liquids). It increases the permittivity, flexoelectricity, electrostriction, and external pressure effects by several orders of magnitude, confirmed experimentally. The theory explains also the formation of polar nanoregions and laxor properties in the paraelectric phase as due to the "local drops formation" when two phases may coexist locally (which is not possible in displacive theories where the formation of a polarized phase requires long-range interaction). A significant part of the paper is devoted to discussion and comparison of the vibronic PJTE theory of ferroelectricity with other theories and empirical data. It is shown that a series of experimentally observed specific properties of perovskite ferroelectrics encounter fundamental difficulties in attempt to explain their origin by means of displacive theories. This is related to the B ion being (instantly) polar displaced along the trigonal axis in all the phases, the order-disorder character of the phase transitions, the role of the spin of the B ion in the ferroelectric polarization, the strong dependence of ferroelectricity and multiferroicity on the chemical composition, the giant effects in interaction with external perturbations, the formation of polar nanoregions in nonpolar phases leading to relaxor behavior, etc. All these unique properties of perovskite ferroelectrics follow directly from the vibronic (PJTE) theory. [ABSTRACT FROM AUTHOR]

An adaptive energy harvesting system for high voltage piezoelectric generators is presented in this paper. Maximum power point tracking scheme is applied in the adaptive system. Low-power-consumption schemes are applied in the control system and harvesting circuit. A self-startup circuit is also applied to the system. Theoretical analysis was explored to determine optimal parameters for the harvesting system. Experiments were done to verify the theoretical analysis. The experimental results show that the harvesting system can achieve an efficiency of 17.5 ∼ 73.3% for piezoelectric generator with a peak open-circuit voltage of 6 ∼ 20 V. And the harvesting system can be self-powered from low input power as 25 μW. The average power consumption of the microcontroller can be low as 3.5 μW. [ABSTRACT FROM AUTHOR]

This paper reviews recent progress on the wearable devices based on piezoelectric sensors. In recent years, many researches have turned eyes to the studies of wearable devices based on piezoelectric sensors because of the sensors' high sensitivity and efficiency. In addition, on account of their numerous advantages, the piezoelectric sensors have made great progress in medical monitoring domain. In this paper, the latest development for the use of piezoelectric sensors in medical devices will be reviewed briefly. The working principle of the piezoelectric sensors will be given. And then, the body parts that can be used for medical monitoring will be illustrated. After that, wearable medical devices made of different materials will be discussed, and their strengths and weaknesses will be analyzed. Finally, all the work listed in this article will be summarized and the future of piezoelectric sensors in the field of medical equipment will be expected. [ABSTRACT FROM AUTHOR]

The paper deals with an optimal control for nonlinear systems with multiple time delays in delta domain. By constructing sequences for optimal control problem, we demonstrate the optimal control and the optimal state trajectories by proving the convergence of these sequences. The optimal control is achieved from deriving a Riccati equation and adjoint differential equations. The compensation term in the designed controller compensates the effect which is produced by nonlinearity, time delay, and disturbance. A quarter-car suspension model with actuator and measurement delays is adopted to illustrate the effectiveness of the proposed control. The advantage of controller in delta domain is obvious than that of the discrete-time domain. [ABSTRACT FROM AUTHOR]

Color gamut of liquid crystal display (LCD) was restricted by traditional white backlight unit (BLU) and color filter (CF). The widely used white light emitting diode (LED) BLU has a broad emission band in green-red region, which results in poor color coordinates and narrow color gamut. Quantum dots (QDs) were introduced into BLU to improve color gamut of LCD, however, there was still a limit caused by the broad absorption peaks of CF. In order to conquer the aforementioned difficulties, a novel quantum dot photoresist (QDPR) was researched and developed in this paper, which could be patterned through photo process including cleaning, coating, exposure, developing and post bake. The patterned QDPR combined with CF can significantly improve color gamut of LCD. There were problems to be overcome though, a feasible method of achieving ultra-high color gamut was presented. [ABSTRACT FROM AUTHOR]

in order to solve the problem that the coating on the steel components is easy to peel off, this paper proposes an innovation that a handshape element shall be added to make a new organic / inorganic “handshape asymmetric” and “nanometer composite coating” by blending method. Depending on the features owned by “handshape asymmetric” — gecko effect and lotus effect, a super strong adhesion between the coating and base material will be formed, as well as a super extraordinary performance isolating from the residues. By this innovation, bottlenecks like the single coating layer is easy to fall off while multi-layer coating is easy to peel off. In this way, the coated steel bar can be more durable. By experiments, it is proved that for the steel components covered with nanometer composite coating has an ability of “self-repairing”, which can slow down the corrosion to the steel bar. For the nanometer additive with handshape element, it has some extraordinary advantages like best “extensibility”, best ability of “self-repairing” and ability resistant to corrosion. [ABSTRACT FROM AUTHOR]

This paper mainly carries out researches on the small part samples of the spindles. Through the Weibull distribution and least squares,the mathematical analysis has made on the lifetime of the spindle parts of the retired machine tool. Through using MATLAB simulation, the theoretical life of the spindle parts is obtained. Then, the motion analysis was made on the old and retired machine tool spindle. At the same time,the finite element model of the spindle is set up with the support of the software ABAQUS. Besides, the static analysis and meshing are conducted to obtain the corresponding stress strain simulation results. Also,the analysis data are imported into the fatigue analysis software NCODE to make the life prediction.Through loading on the old machine tool, the corresponding cloud lifetime chart and damage cloud chart are obtained. The readings of the cloud chart are calculated to obtain the life expectancy which the spindle lifetime can reach and the spindle can be re-manufactured, conforming to the theory analysis results of the Weibull distribution as well as the method of least square.It proves that the method is feasible. [ABSTRACT FROM PUBLISHER]

Femtosecond (fs) laser has the advantages of good beam quality and high precision, which is one of the best methods for processing optical fiber mini-sensors, but residual debris on the surface of the machined fiber structure will affect the sensor performance. In this paper, the laser parameters of laser pulses and translation speed were investigated for the quality of fiber micro-cavities contrast in the air and the water, it was proved the effectiveness of using liquid-assisted to improve the quality of laser micromachining. [ABSTRACT FROM PUBLISHER]

In this paper, we first analyze the motion process of steady-state jets based on the conservation of momentum and establish the control equations. Then we propose an electrospun nanofibers method to increase the acrylic plastic blocks in space, and use the finite element analysis software COMSOL Multiphysics 5.0 to establish the geometrical Model. For the increase of the width and quantity of acrylic plastic block, the distribution of field intensity corresponding to 5 cm and 13 cm below the needle is analyzed. It is found that the field strength increases with the increase of the width of the acrylic block, and the field strength reaches the maximum when reaching 8 cm, which is 7.19 X 104V/m and 5.62 x 104V/m respectively. When the width is 8 cm, two pieces of acrylic plastic block of the same width are made to make the acrylic plastic frame. At this point, the field strengthat 5 cm and 13 cm below the needle continues to increase, and the values are 8.32 X 104V/m and 6.29 X 104V/m respectively. [ABSTRACT FROM AUTHOR]

At present, the mainstream method is directly reduced the platform of the six series branch to six drive rods for analysis and modeling refers to inverse kinematic of the parallel six-degree-of-freedom (6-DOF) Stewart platform, and ignored the influence of the joints that excluded the driving leg on the Stewart platform, resulted in the mathematical model lack of accuracy, there is error in the actual platform. In this paper, the mathematical analysis method of inverse kinematic of the parallel six-degree-of-freedom Stewart platform based on homogeneous coordinate transformation is studied. The relationship of spatial coordinate system is worked up by using the Denavit-Hartenberg (DH) method on the upper and lower platforms and each branch of parallel 6-DOF Stewart platform. Considering the influence among the series branch joints, the transfer relationship is established by using the three-dimensional vector and the homogeneous coordinate transformation matrix between the adjacent joint coordinate systems. The length of the branch drive lever is treated as a variable, the vector equation of the platform system is deduced based on the geometric relation of the parallel 6-DOF Stewart platform. The application of this method in the kinematic inverse solution of parallel 6-DOF Stewart platform is given, verified the correctness of this method. Thinks to the data validation of the actual Stewart platform, it is proved that the proposed method can be applied to the kinematic inverse of parallel 6-DOF Stewart platform that composed of series branch. [ABSTRACT FROM AUTHOR]

ZnV2O6 nanomaterials have attracted great interest in the fields of photocatalysis, sensors, solar cells, supercapacitors, and so on. Some investigators already feel that access to morphology controlled ZnV2O6 is becoming more difficult to obtain, potentially limiting research. For good the optical, electrical, and surface properties, it is critical that ZnV2O6 have a good performance in various applications. This review focuses on the various creative methods for the synthesis and the various applications of ZnV2O6 nanomaterials. As promising materials, ZnV2O6 have demonstrated great potentials in various applications, because of their electrical, optical, and catalytic properties. Besides, we also put forward some views on the challenges and new directions in this field and hoped that this paper can provide some useful information for future research about the design, synthesis and application of ZnV2O6 nanomaterials. [ABSTRACT FROM AUTHOR]

Electrothermal microactuators have a very promising future in micro-electro-mechanical systems applications since they can generate large displacement and force with low actuating voltages and small device areas. In this paper, a temperature distribution and unload displacement model of a Z-shaped electrothermal microactuator is presented. In order to prove the accuracy of the model, finite element analysis (FEA) and experimental results are provided to make comparison. The results of temperature profile and unload displacement output, which are from the model calculation, FEA and experimental test, agree well with each other. It gives an indirect proof that the model is correct and FEA calculation is practicable. It can be shown that the shape of the actuator has no effect on the maximum temperature, and the unload displacement and output force depend on the beam length and inclined angle of the actuator. [ABSTRACT FROM AUTHOR]

The phase transformation mechanism and transformation path of Cu-Ni alloys is very important to study for their applications in excellent electrical properties and chemical catalysis. In this paper, the effect of compressive strain on the transformation path and mechanism of Cu1Ni3 alloy is studied by molecular dynamics simulations. The simulation results reveal that the transformation path of alloys is from Fcc-Bcc-Hcp phase to other phase (amorphous state). The simulations not only revealed the processes of atomic displacements and pair correlation function during the transformation, but also elucidated the underlying mechanism of the transformation at the atomic level. The mechanism of phase transformation could be the lattice reconstruction caused by lattice sliding and stretching. The simulation results provide a clear landscape on the transformation mechanism, facilitating our comprehensive understanding on the phase transition in the Cu-Ni system. [ABSTRACT FROM AUTHOR]

At present, the country vigorously calls for the use of green, energy-saving and environmentally friendly materials in various fields, especially in electronic power systems that require the use of low-loss soft magnetic alloy materials. Amorphous nanocrystalline alloy materials that have received widespread attention have excellent high magnetic permeability and low loss performance. Therefore, this material has become a power system with energy saving, environmental protection and excellent efficiency. Among them, soft magnetic alloys have the most application prospects. In this paper, various amorphous/nanocrystalline samples have been successfully prepared by vacuum arc melting and rapid cooling. Using XRD, HV and SEM testing and analysis methods, the structure, hardness, mechanical properties, magnetic properties and other alloys were successfully prepared. Mo element improves the ability to form glass from amorphous nanocrystalline alloys, the alloy with alloy composition (F e 0.5 C o 0.5 ) 66 N b 6 B 26 M o 2 has the best glass forming ability. The addition of Mo deteriorates the soft magnetic properties of the alloy. The saturation magnetic flux density Ms of the alloy is reduced from 81 to 59 emu/g, but the coercive force is not significantly improved. By increasing the Fe content, the amorphous forming ability and heat the stability decreases, the Vickers hardness and corrosion resistance decrease, and the saturation magnetization and coercivity increase. It can reduce the cost of the alloy and improve the magnetic properties of the alloy. [ABSTRACT FROM AUTHOR]

This paper presented the effect of Ce doping on the structure, morphology and CO2 adsorption performances of MgO-based adsorbents. Nano MgO-based adsorbents were synthesized by citric acid complexation method using Mg(NO3)2·6H2O and Ce(NO3)3·6H2O as the precursors, and characterized by XRD, SEM, N2 adsorption/desorption and FT-IR techniques, respectively. The results demonstrated that with Ce incorporation, the crystal sizes of the adsorbents were obviously reduced, and a large number of micropores and mesopores were formed. The CO2 adsorption of the samples was carried out on a thermogravimetric analyzer, and the adsorption data were fitted by the first-order kinetic equation, the pseudo second-order kinetic equation and the intra-particle diffusion model, respectively. It can be concluded after Ce doping, the adsorption capacity of the adsorbent was greatly improved, due to good dispersity of MgO particles and well-developed porosity, and the increase of the surface reaction rate could be attributed to the increase of BET surface area and the alkaline sites of the Ce-incorporated adsorbents, while the increase of the rate in the diffusion stage was caused by the formation of the porous structure. Therefore, the smaller the crystal size of MgO, the more favorable it was for CO2 capture. This work provided the inspiration of MgO-based adsorbent for improving CO2 adsorption. [ABSTRACT FROM AUTHOR]

The current research based on Bi2Te3 nanomaterials applied in the field of sports rehabilitation is not deep enough. Therefore, the research purpose of this paper is based on the application of fabric sensors modified with Bi2Te3 nanomaterials in the field of sports rehabilitation. First, learn about the basic structure of Bi2Te3 nanomaterials and prepare for the synthesis of fabric sensors based on nano-Bi2Te3 materials with uniform morphology and higher purity. Secondly, fabric sensors are required to improve the response speed and sensitivity of the dynamic response process and be used in sports. Research on rehabilitation is to further improve the practicality of fabric sensors. Finally, the thermoelectric properties of the performance of Bi2Te3 nanomaterials are used, which shows that the material's function of converting thermal energy into electrical energy can help the wide application of fabric sensors. Experimental data shows that the pressure on the sole of the foot using the fabric sensor as a tool is 150 Newtons, and the effect of accelerating the rehabilitation of each joint is 1.5 times. The experimental results show that the fabric sensor modified based on Bi2Te3 nanomaterials can accelerate the rehabilitation process of patients in the field of sports rehabilitation. [ABSTRACT FROM AUTHOR]

Based on the current production technology of sulfate process titanium dioxide, this paper discusses the experimental study on preparation of titanium-rich materials by pressure leaching of titanium concentrate from titanium white waste acid, which combines the comprehensive utilization of titanium white waste acid with the production of titanium-rich material, and studies the effects of acid-ore ratio, leaching temperature and time on the grade of titanium-rich materials. The results showed that the titanium-rich materials in a TiO2 grade of above 80% could be obtained under the conditions of 8 ml: 1 g acid-ore ratio, 150 °C acid leaching temperature and 7–8 hours acid leaching time. In addition, XRD analysis shows that after completion of acid leaching, FeTiO3, the main phase in titanium concentrate, has been converted into TiO2 phase in titanium-rich materials. [ABSTRACT FROM AUTHOR]

This paper describes the manufacture of structural composites incorporating piezoelectric fibres which are finding interest in applications such as shape-changing applications, sensors to detect mechanical strain or vibration and energy harvesting. In this paper preliminary results are presented for a simple cantilever structure consisting of piezoelectric fibres with planar electrodes that are co-cured within a carbon fibre reinforced plastic (CFRP). Processing methods to embed functional fibres are described along with characterization of the piezoelectric and mechanical properties of the resulting material. [ABSTRACT FROM AUTHOR]

The effectiveness of rehabilitation training methods after ligament injury has become an important factor restricting the future development of athletes. Therefore, the study of sports injuries and rehabilitation training methods for athletes in the new era still has important practical significance. This article mainly studies the effect of nano-ligament combined with sports rehabilitation training on the treatment effect of patients with ligament injury. In this paper, the experimental group received 10–15 minutes of rehabilitation training before each training, while the control group did not. Before and after the experiment, perform functional movement test (FMS) and Y-type balance test (YBT) to compare the differences between the physical functions of the two groups of athletes and the lower extremity exercise ability to test the effectiveness of the rehabilitation training method and help the athletes to recover quickly after injury restore. The score comparison between the two groups on the first day of treatment was p > 0.05, and there was no statistically significant difference between the two groups; the score comparison between the third day of treatment and four weeks after treatment was p < 0.05, and the difference between the two groups was statistically significant, A the curative effect of the group was better than that of group B; the score comparison at eight weeks after treatment was p > 0.05, and there was no statistically significant difference between the two groups. There was no significant difference between the FMS test results and the YBT test results of the experimental group before the experiment. The test results of the experimental group after the experiment were significantly higher than the control group (significant difference), indicating that rehabilitation training helps improve and improve physical exercise ability, especially for improvement. The athlete's lower extremity athletic ability has obvious effect. [ABSTRACT FROM AUTHOR]

With the rapid development of global industrialization, the research and development of new thermal insulation materials has great social and economic significance for national development and social progress. Due to the porous network structure of nanotechnology, the porosity of aerogel is 80–99.8%, the thermal conductivity can be as low as 0.013 w/(m k) at room temperature. It is the best insulation material by far, it has important value in the fields of aerospace, petrochemical, electric metallurgy, shipbuilding, precision instruments and so on. This paper is based on aerogel nanotechnology materials at home and abroad. In order to solve the problem of the study on heat transfer characteristics based on nanotechnology is not perfect, and the calculation model of solid phase thermal conductivity coefficient and total thermal conductivity of complex nanotechnology structure is not accurate enough. Through a heat transfer calculation method suitable for nanotechnology to conduct more detailed and in-depth research on these issues, introduces and analyzes the development of the equivalent thermal conductivity calculation model of Novel Aerogel nanotechnology insulation material in recent years. And analyzed The heat transfer characteristics and thermal insulation principle of nanotechnology aerogel by using equivalent thermal conductivity calculation model of aerogel nanotechnology insulation material. Research indicates: For aerogel nanotechnology materials, Use heat transfer calculation method aerogel nanotechnology insulation materials can be well calculated using a heat transfer calculation method that suitable for nanotechnology can calculate the equivalent thermal conductivity of aerogel nanotechnology insulation material very well; nanotechnology particles and aerogel meshes and continuous spatial network structures are reason for the very low thermal conductivity of aerogels; The heat transfer of the material is mainly achieved by convection, radiation and heat transfer. So it is possible to reduce the thermal conductivity from the heat transfer path of the material. [ABSTRACT FROM AUTHOR]

Selenium is one of the necessary nutrients for the growth and development of animals and humans. Improving the activation of selenium in soil is an important way to increase the selenium content in agricultural products. However, nanomaterials have not been applied in the study of soil activation properties. This paper studies the application of nanomaterials in soil selenium activation, clarifies the correlation of selenium transformation in soil under different nanomaterial applications, and explores the adsorption-desorption rules of selenium in soil by adsorption-desorption experiments. The adsorption of Se (IV) by the five nanomaterial culture soils reached equilibrium within 26 h, and the complexation was best at 3 h. With the extension of the application time, the percentages of soil soluble and exchangeable selenium in Nanomaterials 3 and Nanomaterials 4 treatments are increasing, and the increase rates are 1.35%–3.25%, 1.23–4.59%, and 3.96%–5.24%, 3.15%–4.98%. As a whole, the order of the equilibrium adsorption amount is Nanomaterials 3> Nanomaterials 2> Nanomaterials 1> Nanomaterials 4> Nanomaterials 5, and their adsorption amounts are 23.47 mg / kg, 21.69 mg / kg, 20.08 mg / kg, 19.83 mg / kg and 18.10 mg / kg. At 60 d, the soil selenium activation rate reached the highest; after 60 d, the soil activation rate became stable. In the whole process, the activation rate of soil selenium by Nanomaterials 3 and Nanomaterials 4 treatments is significantly higher than that of Nanomaterials 2 and Nanomaterials 1 treatments. It can be seen that these two treatments have the best effect on activating soil selenium. [ABSTRACT FROM AUTHOR]

Calamine can be made into clinical medicinal powder by the traditional calcination water flying method, but its particle size distribution is wide and its specific surface area is small. The application of nanomaterials in traditional Chinese medicine materials shows that part of them can improve the efficacy of traditional Chinese medicine materials. Therefore, this paper attempts to explore the application of nanomaterials in calamine and analyzes the antibacterial effect of nanocalamine in vitro. The experimental results show that the particle size measured by 0.3% sodium pyrophosphate solution is basically consistent with that measured by electron microscope, and polymer dispersity index (PDI) is the smallest. Therefore, 0.3% sodium pyrophosphate solution was selected as the best dispersion medium of calamine nanoparticles. Nanocalamine has the properties of medicinal calamine and nanotraditional Chinese medicine. It shows the active effect of calamine and nanoparticle. The antibacterial activity of nanocalamine is stronger than that of medicinal calamine. The antibacterial activity of calcined calamine is stronger than that of medicinal calamine and weaker than nanocalamine. Alkaline zinc carbonate has no antibacterial activity. Nanocalamine has the characteristics of medicinal calamine and nanotraditional Chinese medicine, which shows the positive role of calamine and nanoparticles. [ABSTRACT FROM AUTHOR]

Nano-carbon materials are widely used and studied in a new generation of energy storage systems. Lithium batteries are widely used in transportation, power networks, and mobile devices. This paper mainly studies the estimation methods of SOC and SOH of lithium batteries based on nano materials. The SOC state equation and output equation of the lithium battery are established by the ampere integration method, and the parameters in the system are observed to achieve the purpose of observing the charging state of the lithium battery online. Using the internal resistance and SOC of the cell model as state parameters, the nonlinear transfer of equal and covariance is handled. The working voltage was modified using the lithium battery model, and different control methods were implemented for different SOC situations. According to the experimental data, the voltage estimation error is less than 2.1%, which can meet the actual use requirements. It was found that there are different types of lithium-ion batteries, and the model obtained by training samples of lithium-ion batteries reduces the prediction accuracy when predicting other lithium-ion batteries. [ABSTRACT FROM AUTHOR]

The emergence of nanotechnology provides a new method for the development and application of nanomaterials in the medical field. Nanoparticles could promote the expression of vascular endothelial growth factor (VEGF), dilate the coronary artery, improve the cardiac mechanism and reduce the recurrence rate of angina pectoris. Nanoparticles have the advantages of large specific surface area, high surface reactivity, high catalytic efficiency and strong adsorption capacity, which provide a new method for biomedical research. This paper mainly studies the application of nanoparticles in the diagnosis and treatment of coronary artery disease under the intervention of exercise rehabilitation. Then the prepared nanoparticles were added into the medium for co culture. The effect of nanoparticles on coronary cells was observed. It was found that the detection of zinc in the extracellular medium and in the cell increased with the increase of the concentration of ZnO NPs, and the differences were statistically significant (F = 13012.34, P < 0.001; F = 7033.54, P < 0.001). The results showed that the nanoparticles could promote the expression of vascular endothelial growth factor (VEGF), dilate the coronary artery, improve the cardiac mechanism and reduce the recurrence rate of angina pectoris. [ABSTRACT FROM AUTHOR]

In order to study the application of nano carbon water retaining fertilizer in agricultural production, and to explore the effects of its use on the bacterial community structure of agricultural soil and crop growth, a series of experimental studies were carried out in a grape field. In this paper, the coated slow-release fertilizer with soluble nitrogen particles as the core and nano carbon materials wrapped in the outer layer of nitrogen fertilizer was developed. The grape field used in the experiment was divided into experimental field and control field. The new nano carbon water retaining fertilizer was applied in the experimental field and ordinary nitrogen fertilizer was applied in the control field. Through Illumina Miseq high-throughput sequencing, the diversity and richness of bacterial communities in the original soil without planting and the soil of two groups of grape fields after grape ripening were detected, and the grape leaf area, single fruit weight and horizontal diameter of grape, and the titratable acid content of grape fruit in the two fields were detected and calculated. The results showed that Shannon index and Chao1 index of soil bacterial community diversity in the experimental field were higher than those in the control field; the grape leaf area in the experimental field was larger than that in the control field in the early, middle and late stages of shoot growth, with a difference of 8.56cm2 in the later stage; the single fruit weight and transverse diameter of grape in the experimental field were 1.94 g and 2.72 mm larger than those in the control field at 100 days after flowering, respectively; The difference of titratable acid content in grape fruit was the largest at 70 days after anthesis, which was 0.25% and 0.05% at 100 days after flowering. The results showed that nano carbon water retaining fertilizer had significant effects on soil community structure and grape growth in grape field, which could effectively reduce the influence of planting and fertilization on soil bacterial community diversity and richness, promote the growth of grape leaves and fruits, and improve grape quality. [ABSTRACT FROM AUTHOR]

Using vanadium oxide (VOx) thin film as active layer, microbolometer with gold black absorber was fabricated due to the high mid-infrared (8-14μm) absorption property of gold black. This paper describes the design and fabrication of microbolometer with micromachining surface technology. The characteristics of the device are investigated. The detector performance exhibits maximum detectivity of 1.96 × 108cmHz1/2/W at 17 Hz with 8.8μA. [ABSTRACT FROM AUTHOR]

Aiming at the temperature control of the multi-loop engine cooling system, this paper establishes a mathematical model of the multi-loop cooling system. Taking the engine multi-loop temperature control and energy consumption optimization as research goals, a nonlinear adaptive control strategy based on Lyapunov is proposed. It achieves the engine and transmission temperature control and compensation for unknown heat load. The fuzzy control method is introduced as a comparative experiment. The results show that the designed nonlinear adaptive control strategy has fast response speed, small steady-state error, and 10.7% reduction in energy consumption. This study provides help for the research of multi-loop engine cooling system. [ABSTRACT FROM AUTHOR]

Use CaO-Al2O3-SiO2 glass-ceramics from gold tailings in Hanyin as main raw materials, which were prepared by a melting method. In this paper, the effects of nucleation temperature and crystallization temperature on microstructures and properties of the glass-ceramic specimens were investigated. The thermal property of the glass-ceramics was discussed by differential scanning calorimetry (DSC), and microstructure was characterized by X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). Methods of a 4-point bending strength test, DIL-402C dilatometer and Archimedes method were used to determine the bending strength, thermal expanding coefficient and density of glass-ceramics. The experiment results indicated that the optimal properties of glass-ceramics were obtained by nucleation at 800 °C for 2 h, and then crystalling at 950 °C for 3 h. XRD analyses demonstrated that the main phase of gold tailings glass-ceramics was augite and diopside (CaMgSi2O6), and the minor phase was potassium iron silicate (KFeSi2O6). The bending strength, density and thermal expanding coefficient of the glass-ceramics were 128 MPa, 2.840 g/cm3 and 7.85 × 10−6/°C, respectively. [ABSTRACT FROM AUTHOR]

This paper mainly studies the influence of clinker mineral composition on the performance (flow variability and expansion performance, hole structure, etc.) of silicate cement. The experimental results show that the shear stress of silicate cement slurry body consisting of different minerals is different with the rheography curve of shear rate, and the linear relationship between the two belongs to Bingham rhesino equation, the expansion rate is also quite different, the expansion rate of D mineral composition is the largest, and the distribution of the aperture of different minerals composition is different, the size of the gap and the degree of hydracy are different. [ABSTRACT FROM AUTHOR]

Ga- doped ZnO films and Ga-Al co - doped ZnO films were prepared on glass and Si substrates by sol - gel spin coating. The crystal structure of the sample film was characterized by X-ray diffractometer (XRD), the surface morphology of the film was measured by scanning electron microscope (SEM), the optical properties were investigated by UV-vis spectrophotometer, and the luminescence properties were analyzed by photoluminescence spectrum (PL spectrum).In the experiment on the effect of Ga doping amount on ZnO thin film, Ga doping did not change the structure of ZnO hexagonal wurtzite. A proper amount of Ga will make the grain of the film grow optimally along the c-axis, the grain size becomes smaller, and the film surface becomes smoother and smoother. When Ga doping amount is 3 at%, the film has the best preferred orientation, the most uniform grain growth, and the highest transmittance in the visible region. The effect of Al doping amount on Ga-Al co—doped ZnO thin films was investigated in this paper. The doping amount of Ga was controlled as 3at%, and the doping amount of Al was 0.5 at%, 1.0 at%, 1.5 at%, 2.0 at%, and 2.5 at%. It was found that the addition of an appropriate amount of Al ion would make the grain grow along the horizontal direction, reduce the grain gap on the surface of the film, make the surface smooth and smooth, and improve the crystallization and optical properties of the film. When Ga doping amount is 3.0 at% and Al doping amount is 2.0 at%, the average transmittance of the film in the visible light region is the highest (92%) and the forbidden band width is the largest (about 3.95 ev). At this time, the near-band emission peak of the film is the strongest and the defect luminescence peak is the weakest. [ABSTRACT FROM AUTHOR]

In this paper, the adsorption capacity of CNT modified polyacrylonitrile (PAN) film on copper ions under different conditions was studied by the adsorption experiment of the prepared multilayer diazo resin acidified carbon nanotubes/PAN composite film. The concentration of copper ion solution before and after adsorption was measured by inductively coupled plasma (ICP). The results show that the adsorption capacity of the pan film modified by CNT increases first and then reaches the adsorption equilibrium with the increase of the adsorption time of copper ion, and the adsorption capacity of the pan film modified by CNT increases with the increase of the initial concentration of copper ion and the external temperature With the increase of solution pH, the adsorption capacity of CNT modified polyacrylonitrile membrane to copper ion increases first and then decreases; after multiple desorption/adsorption of the modified membrane which has reached adsorption equilibrium, the membrane still has CNT adsorption capacity to copper ion, indicating that the membrane has excellent recycling performance. [ABSTRACT FROM AUTHOR]

In this paper, 3D dual impeller stirring tank was used as a model to simulation combine with experiments to explore the acid leaching kinetics of high-calcium and -silicon manganese ores. The effects of stirring speed, temperature, and aeration rate on the spatial distribution of gas and liquid phases were investigated, and the influence of the gas phase on the flow state was further explored by using CFD (Computational Fluid Dynamics). Meanwhile, the effects of stirring speed, temperature, and aeration rate on the leaching rate of target element manganese were studied by experiments. According to simulations and experiments, stirring speed at 500 rpm perfectly. The aeration rate was 7 m/s, the suitable leaching temperature was 140 °C by experiments. These results also showed that the leaching of high-calcium and -silicon manganese ores follows the control of Interface chemical reaction.The apparent activation energy of the reaction was 43.4 kJ.mol−1. [ABSTRACT FROM AUTHOR]

Barium titanate prepared by two step sintering method is preferred for its small grain size approximately 1 µm and high piezoelectric constant 470. In this paper, finite element analysis (FEA) is performed to quantitatively determine the influence of external applied stress on the generated surface potential and polarization effect for both poled and unpoled BaTiO3. The modeling simulation verified that poled BaTiO3 is approximately 1.5 times more responsive to applied stress. The results also indicate that the maximum surface potential is generated when stress is applied parallel to the direction of electric dipole. [ABSTRACT FROM AUTHOR]

(1−x)Bi1/2Na1/2TiO3–xBa1/2Sr1/2TiO3–0.05KNaNbO3 (BNT–BST–KN, x = 0.01, 0.03, 0.05, 0.07) lead-free anti-ferroelectric ceramics were synthesized by a conventional solid-state. The hysteresis loop of the ceramic at different temperature under 70 kV/cm electric field was analyzed. In this paper, the energy storage properties of BNT–BST–KNN ceramics are studied. It was found that the addition of Sr element helps to improve the electric field strength tolerance and the breakdown resistance performance the material, so as to improve its energy storage density. At room temperature, the P–E curves of the materials in the system basically show a double hysteresis loop, and with the increase of temperature, the characteristics of the double hysteresis curve are particularly obvious. The ceramics exist in the ferroelectric–antiferroelectric coexistence phase region near 303 K, namely the morphotropic phase boundary region. It shows that the ceramic has anti-ferroelectric characteristics at room temperature, and is a typical anti-ferroelectric material. [ABSTRACT FROM AUTHOR]

In this paper, an energy harvesting floor based on piezoelectric transducers is studied. A structure with multiple layers of piezoelectric beams is designed. Different striking frequencies are studied. Fourier transform is applied to analyze the frequency characteristic of the output voltage. Experiments are explored to find out the optimal external load resistance for maximum output power. The experimental results show that, with three piezoelectric transducers in a beam array, and a stroke of 4 mm at the striking frequency of 1.263 Hz, the maximum output power is 733.5 µW. [ABSTRACT FROM AUTHOR]