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Research on the image detail enhancement algorithm of nanocomposites can better improve the image quality of nanocomposites and facilitate researchers to understand the structural characteristics of materials. Due to the problems of low image quality and difficulty to retain the details of traditional nanocomposite image details enhancement algorithms, a new nanocomposite image details enhancement algorithm based on deep convolution neural networks (DCNN) is designed. Through histogram equalization, linear gray-scale stretching and median filtering, the image of nanocomposite is preprocessed, and then FCM algorithm is used for edge detection and image segmentation. Using color model transformation algorithm and DCNN, an image detail enhancement model including feature extraction and nonlinear mapping is constructed. Finally, the idea of image detail reconstruction is introduced, and image detail reconstruction is realized through a convolution layer. The results show that compared with the experimental comparison algorithm, the image processed by the proposed algorithm contains more detailed information and has higher image quality. The PSNR value reaches 27.1 dB, which indicates that the nanocomposite image has a better detail enhancement effect and can be widely used in the field of nanocomposite analysis and research. [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]

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]

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]

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]

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, 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]

In this paper, an electromagnet power energy harvester is proposed and experimented that using galloping force to achieve wind energy converting into usable electricity. When the device is subjected to a relative low wind speed excited, due to the galloping force, the square prism vibrates at a certain angle in the direction perpendicular to the wind excitation. To achieve multiple directions wind energy scavenging purpose, a 3 × 3 magnets array is determined to obtain the maximum flux changing rate at multiple directions of wind. It is indicated that the proposed energy harvester exists a maximum power 0.124 mW at 2.0 m/s. [ABSTRACT FROM AUTHOR]

PP + ZrO2 polymer nanocomposites obtained through different temperature-time modes of crystallization and exposed to electrothermopolarization were studied in this paper. Even though the preparation method of nanocomposite samples was the same, their lifetimes and surface charge density were different. It was investigated that nanocomposite obtained by slow-cooling (SC) conditions has high stability but low surface charge density. It was also revealed that the dependence of relaxation time of the electret state on the percentage content of filler has a nonmonotonic character. The change of the thickness of the interphase layer of nanocomposite depending on cooling rate is explained by the change of the supramolecular structure of the polymer and the interphase interaction among the components of the nanocomposite. It was considered that the change of the thickness of the interphase layer of the nanocomposite depending on the intensity of the electric field during electrothermopolarization due to the difference in charge accumulation during the polarization process. [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]

The presence of fabrication errors in domain engineered quasi-phase-matching (QPM) device directly affects its performance in a nonlinear optical process. The existence of error in the aspect ratio affects the conversion efficiency factor. In this paper, we theoretically analyzed the effect of aspect ratio errors in QPM device. Further, the effect of duty cycle error and incomplete domain inversion on conversion efficiency is also studied for various grating profiles like under-poled, rectangular, and blazed. Their generalized phase profile equations representing the nonlinear optical coefficient have been derived and their corresponding second harmonic efficiency factors are calculated. [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]

In this paper, amplitude dependences of areas of polarization loops S(E) at different frequencies of the measuring electric field E in multicomponent ceramics based on PZT are studied. An existence of two ranges of the measuring fields is revealed, where the dependence S(E) obeys the power law S ∼ Eσ, similar to the Steinmetz law for ferromagnetic materials. [ABSTRACT FROM AUTHOR]

The results of the dielectric, pyroelectric, and piezoelectric studies of aluminum nitride single crystals are presented in this paper. The crystals were grown by sublimation and hybrid-chloride vapor phase epitaxy, which provided high growth rates, large sizes, and the ability to reduce structural defects. The pyroelectric effect measurements by a dynamic method using infrared laser radiation (λ = 980 nm) revealed high values of the pyroelectric coefficient up to 30 µC/(m2K). The piezoelectric coefficient d31 was found about 1.6⋅10−12 m/V. [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 4mm at the striking frequency of 1.263 Hz, the maximum output power is 733.5 μW. [ABSTRACT FROM AUTHOR]

In this paper, an electromagnet power energy harvester is proposed and experimented that using galloping force to achieve wind energy converting into usable electricity. When the device is subjected to a relative low wind speed excited, due to the galloping force, the square prism vibrates at a certain angle in the direction perpendicular to the wind excitation. To achieve multiple directions wind energy scavenging purpose, a 3x3 magnets array is determined to obtain the maximum flux changing rate at multiple directions of wind. It is indicated that the proposed energy harvester exists a maximum power 0.124mW at 2.0 m/s. [ABSTRACT FROM AUTHOR]

The paper considers the problem of determining the effective properties of piezoceramics with metal inclusions. The homogenization problem was numerically solved in the representative volume with closed structure of inclusions. The effective moduli behavior was analyzed depending on the fraction of inclusions for piezoceramic PZT-5A with platinum inclusions. An increase in the effective stiffness moduli, the longitudinal and shear piezoelectric stress coefficients, and a considerable increase in the dielectric permittivities were discovered with the growth of the metal inclusions fraction. The effective dielectric permittivities grew for the same fraction of inclusions when the relative size of inclusions increased. [ABSTRACT FROM AUTHOR]

Ex-situ local switching is a useful method for studying the domain structure evolution during polarization reversal in the individual grains of the ferroelectric ceramics. In this paper, the local switching by a biased tip of atomic force microscope was studied in the single crystals and ceramics of barium titanate BaTiO3 (BTO). The initial domain structure in BTO crystal was also studied. The domain growth during local switching in the crystal and individual grains of ceramics was characterized in terms of the parameters of the domain wall motion. [ABSTRACT FROM AUTHOR]

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]

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]

Professor Boris Anatol'evich Strukov, a renowned scientist in the field of ferroelectrics, passed away at the age of 88 in Munich, Germany. He had a distinguished career at Moscow State University, where he made significant contributions to the study of phase transitions in ferroelectric crystals. Professor Strukov was known for his meticulous approach to experimental research and his dedication to understanding the underlying theories. His work challenged existing theories and provided valuable insights into the behavior of ferroelectric materials. He also co-authored a popular textbook on ferroelectricity and continued to engage in conceptual discussions even after retiring from teaching. Professor Strukov's legacy includes his numerous publications and his passion for scientific curiosity. [Extracted from the article]

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]

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]

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]

In this paper, we study the magnetic properties of a bi-layer borophene structure with RKKY (Ruderman-Kittel-Kasuya-Yoshida) interactions. The system is composed by two magnetic layers with mixed spins σ = ±3/2, ±1/2 and S = 0, ±1, separated by (L) non-magnetic planes. Firstly, for zero temperature, the ground state phase diagrams are reported and discussed. Secondly, we use the Monte Carlo simulations to explore the RKKY interactions effect on the magnetic properties of the system. The transition temperature increases when decreasing the number (L) of nonmagnetic layers. Also, the effect of the exchange coupling interactions on the transition temperature behavior is studied. Finally, we report the effect of different physical parameters on the magnetic hysteresis cycles. [ABSTRACT FROM AUTHOR]

The substrates in Trapezoidal Bridge piezoelectric transducer will shield most of the stress, causing unutilised low stress regions of PZT and lower power output. Thus, this paper presents an improved optimisation scheme by optimising the overall stress distribution of the PZT with the considerations of suitable loading forces and optimised dimensions of amplifier structure. The developed Finite Element Model had been validated experimentally. It is found that the thickness of end cap and substrates are the important parameters in optimising the PZT transducer. The overall PZT's stress level has been enhanced with a much closer stress distribution to its threshold. >Improved optimization scheme is proposed to enhance the overall stress distribution. >It integrates the average nodal stress of PZT and loading force environment. >Increasing overall PZT's stress level is crucial to fully utilize the PZT material. >Power generated will be maximized but restricted due to PZT's size constraint. >Optimization procedure and amplification factor calculation are performed and explained. [ABSTRACT FROM AUTHOR]

In this paper, effects of sintering temperature (Ts) and dwell time (td) on crystalline structure, microstructure and electrical properties (dielectric and ferroelectric) of BiFe0.96 Zn0.02Ti0.02O3 (BFZTO) ceramics synthesized by sol-gel method were investigated. The crystalline structure of BFZTO ceramics remained unchanged with different sintering conditions. The microstructure of BFZTO ceramics have an evident modification by changing sintering temperature and dwell time. With increasing Ts or td, grains of samples become larger. Because of the differences of sintering pross, The large grains and low porosity led to the alignment of the dipole, the low coercive field (Ec of ca. 12 kv/cm), low leakage current density (10−1 μA/cm) and good remnant polarization (Pr of ca. 1.2 μC/cm2) were achieved in BFZTO ceramics at Ts = 800 °C, td = 1 h. While the excessive Ts or td resulted in lower number of defect complexes, which had significant influence on ferroelectric properties. The work reported herein demonstrated that the porosity, grain size and the presence of defect complexes have a big part in determining ferroelectric properties of BFZTO ceramics. [ABSTRACT FROM AUTHOR]

Based on density functional theory, this paper has investigated the stability and electronic structure of Ni–Fe alloy within three different space groups using the first-principles method, and calculated the binding energy, differential charge density and electronic density of states of the optimized space groups. The results show that the order of the three space groups' stability is Pm-3m, I/4mmm and Fm-3m, respectively. Moreover, we find that the bonding electrons are mainly distribute in the range of –5–2 eV, which is mainly contributed by the valence electrons of Fe-3d and Ni-3d. Meanwhile, the s-p electrons show obvious non-localization. This phenomenon indicates that the lost electrons of iron atoms are transfer to nickel atoms, forming metal bonds. [ABSTRACT FROM AUTHOR]

In this paper, the effect of different masses of the inertia-type piezoelectric actuator is investigated within the general operating frequency range of most of the power tools. The inertia piezoelectric actuator was applied to the active suspended handle system to reduce the shaker-excited vibration for both frequency independent and dependent excitations. For the condition of frequency independent excitation, the results showed that the acceleration of the active suspended handle was reduced up to 39.69% for 45 g of inertia mass. Inversely, for the frequency dependent excitation condition, the maximum vibration reduction i.e., 34.98% was achieved by 95 g. [ABSTRACT FROM AUTHOR]

In this paper, waste concrete of different strength grades is used as a substitute for calcareous and siliceous materials. The effects of waste concrete with different strength grades, various raw material compositions, distinct calcination temperatures, burnability of cement clinker, lithofacies characteristics and microscopic morphology hydration products are studied systematically. The results demonstrate that waste concrete is conducive to the low temperature formation of clinker mineral phase, which promotes the firing of clinker and the incorporation of low-strength grade waste concrete benefits the calcination of raw material more obviously. Under the same conditions, the content of f-CaO in recycled cement clinker shows an upward trend with the increase of the strength grade of KH and waste concrete. Meanwhile, if the amount of waste concrete exceeds 40%, the stability of recycled cement would be poor. Alite and Belite crystals are formed with obvious characteristic peaks in the waste concrete calcined regenerated cement clinker of different strength grades. However, each sample group has different degrees of over-burning phenomenon, it is difficult to identify the adhesion between A and B minerals in clinker. The regenerated cement hydration products have different degrees of C-S-H gel and ettringite formation, the hydration products of recycled cement prepared by waste concrete with low strength grade are more compact. [ABSTRACT FROM AUTHOR]

A new method for prototype of a three dimensional (3 D) microfluidic device on piezoelectric substrate was presented. Wires were stick by colloidal starch, and dried in a thermotank for three dimensional channels mold. The mold was slightly placed in a groove with poly(dimethylsiloxane). After having been solidified, these wires were drawn off to form 3 D microchannels. Surface acoustic wave was used to driven sample droplet to the inlet of the microchannel in microfluidic device. Red fluid transportation in different microchannels was successfully demonstrated using the 3 D microfluidic device at 24.5 dBm signal power for verifying the function of the microfluidic device. [ABSTRACT FROM AUTHOR]

In this paper, the polarization curve and corrosion amount of aluminum alloy 1050 in 30 mass% nitric acid solution were measured as the corrosion potential under natural corrosion. it was found that the surface corrosion of aluminum alloy was uniformed and the corrosion rate calculated according to the weight loss-time curve was 0.25 mA·cm−2 by observing the corrosion morphology. The polarization resistance curve was obtained by differentiating the polarization curve. The corrosion rate calculated by analyzing the characteristics of the polarization resistance curve was 0.29 mA·cm−2, which was close to the actual corrosion rate obtained by chemical erosion. [ABSTRACT FROM AUTHOR]

For the current problems of the high voltage device of autonomous safety, warning is required manual input of the voltage classes. A method of dividing the insulator image based on the simplified model of PCNN is proposed to extract the number of insulator sheds of a string to independently identify the voltage of high voltage transmission line. Because the image segmentation effect of PCNN model is closely related to its many parameter tuning, however, the PSO algorithm is used to select the optimal PCNN parameter to realize the binary segmentation of the Insulator image in this paper, and then the transform angle of the image region is corrected so that the Insulator horizontal array, and then according to the shape of the Insulator binary image characteristics to extract the number of Insulator Sheds in order to achieve the transmission line voltage classes of self-identification. The experimental results show that the method can identify and extract the number of Insulator Sheds, and has strong practicability. [ABSTRACT FROM AUTHOR]

In this paper, microstructural, ferroelectric and magnetic properties of multiferroic composite system (1-x) Ba0.5Sr0.5TiO3(BST) – (x) Ni0.4Co0.2Zn0.4Fe2O4(NCZF), where x = 0.1, 0.2, 0.3, 0.4 molar ratio have been studied. Grains of NCZF are larger in size and more symmetrical in comparison to BST grains. Overall grain size of BST grains in the composite samples decreases with increase in NCZF content. Polarization vs Electric Field (P-E) loops of the composite samples are unsaturated. The values of remanant polarization of the composite samples increase with increase in NCZF content. The composite samples possess saturated M-H loops with the values of remanant and saturation magnetization increases with increase in NCZF content. [ABSTRACT FROM AUTHOR]

The paper investigates the magnetobarocaloric effect in a multiferroic composite made of ferroelectric and manganite components. Such a phenomenon can be classified as a secondary multicaloric effect. Its theoretical description is provided. In the presence of a magnetic field a temperature-dependent elastic field arises in the magnetostrictive material that results in the magnetobarocaloric effect. The effect reaches its maximum entropy change of 0.044 J kg−1K–1 at 312.5 K for the composite under study. [ABSTRACT FROM AUTHOR]

Ferroelectric materials with high Curie temperatures, TC, and tuning of the TC over a large temperature range are very important for the basic sciences and engineering. This paper reviews the various types of high-temperature ferroelectrics with perovskite, bismuth layered, tungsten bronze, and perovskite slab structures, especially Sr2Nb2O7 with TC = 1342 °C and its family. The lattice instability of the high-temperature ferroelectric phase transitions is also discussed. The superior tunability of the TC is achieved by the substitution of cations at the A- and B-sites in the perovskite-like structures. The variation of the soft optic and relaxation modes and elastic anomalies related to structural phase transitions were discussed in relation to the A- and B-site substitutions of oxygen octahedral ferroelectrics, especially Ba2NaNb5(1-x)Ta5xO15 with a tungsten bronze structure and (BaxSr1-x)2Nb2O7, Sr2(Nb1-xTax)2O7 with the perovskite slab structure. [ABSTRACT FROM AUTHOR]

In this paper, the development in the field of ferroelectrics is reviewed by summarizing the topics in the field as presented at the International and European conferences on Ferroelectrics. While from the very beginning in 1966 until now fundamentals in ferroelectrics always played a significant role, it is shown that the topics considerably broadened over the years and are nowadays barely overlooked. Polarity dominated the field from the beginning; however, now its combination with more exotic properties like skyrmions, magnetism, functional domain walls has entered the stage and substantially enlarge the field of applications. [ABSTRACT FROM AUTHOR]

This paper proposed a new piezoelectric transformer structure based on shear vibration modes. The difficulty in the preparation of shear vibration piezoelectric transformer was minimised using the integrated structure design. The transformer working mode was determined using a finite element simulation and laser vibrometer. A transformer preparation methodology was designed, and the transformer samples were fabricated. The test results showed that by optimising the area ratio between the input and output of the piezoelectric transformer, its voltage ratio, operating frequency, efficiency, and other parameters can be adjusted. The piezoelectric transformer samples were tested at 110 kHz. The maximum variable voltage ratio and efficiency can reach 34.1 and 91%, respectively. [ABSTRACT FROM AUTHOR]

IWMN-2022 covered a wide range of scientific topics: Characterization of micro- and nano-materials; Micro- and nano-domain engineering; Relaxor and multiferroic materials; Ceramics and films; Bioinspired materials. These Proceedings contain a collection of papers based on the invited, oral, and poster presentations at the B Fourth International Workshop Modern Nanotechnology (IWMN-2022) b , which was held in Ekaterinburg, Russia, August 24-27, 2022. More than 130 scientists from 19 cities of Russia and three countries: Belarus, Czech Republic, and Israel presented their results. [Extracted from the article]

The influence of double sintering temperature on the phase structure, micro-structure and piezoelectric properties of Ba1-xCaxZr0.1Ti0.9O3 (x = 0.055) double sintered ceramics has been systematically studied. The pellet sample preparation and characterization have been reported in this paper. The converse piezoelectric properties of the Ba1-xCaxZr0.1Ti0.9O3 (x = 0.055) were observed. Depending upon the sintering temperature, the grain size and density of BCZT ceramics have been changed. The P-E loops, strain%, and the polarization current were measured. The value of d33 was decreasing with the application of an electric field in case of double sintered pellets. For sample x = 0.055, the value of d33* at 1300, 1400 and 1450 °C temperature, was 173 (pm/V), 130 (pm/V), and 75 (pm/V), respectively, at applied field 29.33 kV/cm. [ABSTRACT FROM AUTHOR]

Ferroelectric domain structures have attracted much attention due to their potential applications in storage. In this paper, the molecular dynamics method based on shell model is employed to simulate the uniaxial tensile strain applied to the BaTiO3 thin film, and the effect of strain on the polarization domain structure of BaTiO3 thin film is discussed. The results show that with the increase of strain, the polarization configuration of BaTiO3 film evolves from the initial 180°domain structure to the vortex domain configuration. Moreover, the vortex domain will show certain movement rules with the increase of stress. These results are beneficial to the application research of ferroelectric storage. [ABSTRACT FROM AUTHOR]