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In order to study the stability of slopes containing weakly inter bedded rocks under dynamic disturbance, the dynamic response characteristics of rocks with different inclinations under dynamic cyclic disturbance are investigated through indoor experiments on rock specimens with different inclinations and the construction of a dynamic model of the structural surface of the rock body under dynamic disturbance. The results show that the stress-strain curve under cyclic disturbance is a closed hysteresis loop curve, and its general stage is characterized by: sparse-dense-sparse; when the disturbance amplitude is constant, the rock deformation increases with the increase of inclination angle. For the rock specimen with the same inclination angle under the same static load stress, there is a disturbance threshold for the disturbance destructive stress amplitude of the rock structural surface. In the case that the disturbance amplitude is less than this threshold, the plastic deformation of the rock body is relatively stable. Once the perturbation amplitude exceeds the threshold, the structural surface of the specimen is damaged and the plastic deformation is destabilized, which is manifested by the S-shaped curve of the plastic accumulation and the number of cycles. It is shown that when the inclination angle of the structural face is greater than 30°, the damage of the structural face is not only material damage, but also shear damage occurs at the junction position of the structural face of the rock body, leading to the destabilization of the entire structural face of the rock system.

To explain the moisture adsorption properties and improve the package material of polydextrose product, the adsorption and desorption isotherms of five domestic samples with initial moisture content (IMC) of 1.01%~4.89% were determined in this study in the range of 20~35 ℃ and ERH10%~90% using a dynamic water sorption analyzer. The adsorption and desorption isotherms were sigmoidal-shaped curves, and there was a hysteresis between desorption isotherm and the adsorption isotherm when ERH was less than 80%. Because polydextrose is an amorphous phase powder, we assumed that the water adsorption process of polydextrose was an equilibrium that existed among the vapor phase, the liquid phase (polylayer adsorption) and the solid solution (monolayer adsorption), and the adsorptive and desorptive sigmoidal-shaped isotherms can be de-convolved into a monolayer (Mh) and a polylayer component (Md) in accordance with Hailwood- Horrobin (HH) model. The polylayer water content of adsorption and desorption showed a sigmoidal increase with increasing ERH. The monolayer water content of desorption remained constant with increasing ERH, while that of the adsorption increased slowly for samples a1 to a4 with IMC 4.87% to 2.35% and decreased almost linearly for sample a5 with IMC 1.01%. As the IMCs of the samples decreased, the molecular weight of the polymer at the sorption site was maximum for sample a1 and minimum for sample a5. Although the FTIR showed the smallest intensity of hydroxyl group (3 416 cm–1) and amorphous structural functional group (1 027 cm–1) for a5 sample, a5 sample had the largest moisture absorption rate. These results suggested that, for the lower moisture content of polydextrose samples processed by different processes, their adsorptive monolayer water content seemed to decrease almost linearly with an increase of ERH. However their adsorptive polylayer water content sigmoidally increased with an increase of ERH, and their moisture absorption rate and hygroscopic capacity increased.

For seeking the cause of the increase in dough water absorption rate after cold plasma treatment, this study adopted low-pressure, radiofrequency 120 W helium cold plasma (CP) to treat wheat flours from 0 s to 180 s. Results showed that water absorption rate, conductivity, values of water and sucrose solvent retention capacity (SRC), and paste breakdown value in wheat flours increased significantly with increasing CP treatment time. To further explore the change causes in these physiochemical indexes, we developed a seven- parameter polynomial , (M was equilibrium moisture (%), ERH was equilibrium relative humidity (decimal), t was temperature (℃), and A~G were parameters. This polynomial could fit moisture sorption isotherms (20-35 ℃ and ERH 10%-90%) of helium CP treated flours, and the goodness-of-fit indexes were superior to those of modified Chung-Pfost (commonly used) and four-parameter polynomial (without temperature term) equations. The seven-parameter polynomial equation clearly showed the hysteresis loops between moisture adsorption and desorption isotherms of flour samples, which shifted downward with increasing temperature. The hysteresis degree showed a parabolic shape curve with increasing ERH, and the vertex of the parabola was at the range of 40-50% ERH. CP treatment shifted the monolayer adsorption sites to multi-molecular adsorption sites ahead of schedule, from ERH 50% to 40%. Further analysis using Dent model showed that the helium CP treatment was able to reduce the mono-layer moisture content and spreading pressure in wheat flour, and increase the elasticity of a capillary wall. The ability of water molecules was increased to form hydrogen bonds with the chemical components, which promoted the uniform distribution and permeation of water molecules into flour particles. Infrared spectral scanning showed that the degree of short-range order at the surface of starch granules and the interaction between protein and starch tended to increase with increasing CP time. Helium cold plasma technology has potential application in improving flour processing quality.

The analytical Preisach model solves the problems of large measurement error and numerical instability caused by discrete Everett function in the Preisach model, but there are many parameters and complicated identification problems in the model. In order to solve these problems, an improved chimp optimization algorithm based on multi-strategy fusion was proposed to achieve fast and accurate parameter identification of analytic Preisach model. Firstly, adaptive weighting factors were introduced to balance the global search and local exploitation capabilities. Secondly, the differential variance strategy was applied to update the position of individual populations, to enhance the exchange of information between individual algorithms and expand the search scope. Finally, a stochastic perturbation strategy using a combination of Cauchy and Gaussian variants was used to further enhance the algorithm’ s ability to jump out of local optima. Combined with the experimental data, genetic algorithm, chimpanzee algorithm and the algorithm proposed were used to identify the parameters of the analytical Preisach model. Based on the identification results, the hysteresis loops of the oriented silicon steel sheets were simulated. By comparing the results of hysteresis loop fitting degree, iteration times and fitness value, it can be seen that the proposed algorithm has the advantages of high identification accuracy and fast convergence speed in the identification of parameters of analytic Preisach model. [ABSTRACT FROM AUTHOR]

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

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

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

In order to study the influence of low gas content and high gas pressure of the occurrence of the lower 5# coal seam of Yushuling Coal Mine in Xinjiang on the sensitivity of coal seam drillings gas desorption index, this paper adopted a constant temperature gas release test and low-temperature liquid nitrogen adsorption method to determine the gas adsorption law and pore composition of the coal samples of the lower 5# coal seam of Yushuling and the coal sample of Duanshi No.3 coal seam, to summarize and analyze the influence of pore structure characteristics and gas desorption rate of coal samples with different degrees of metamorphism on the accuracy of drillings desorption index. The results show that: the degree of coal metamorphism and pore structure have a great influence on gas desorption and diffusion rate, and the overall trend of gas desorption rate of Yushuling low-rank gas coal is stable in the first 10 min, while the trend of gas desorption rate of Duanshi high-rank anthracite is faster in the first 4 min and stable in the last 6 min; the correlation between drillings gas desorption index K1 and gas pressure p of Yushuling coal is poorer than that of Δh2, while the correlation between K1 and gas pressure p is better than that of Δh2 for Duanshi coal drillings gas desorption index. The analysis concludes that Δh2 is more suitable as a predictor of the outburst of low-rank coal, and K1 is more suitable as a predictor of the outburst of high-rank coal.

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

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

Runoff and sediment characteristics can be the important indicators on the soil erosion. However, it is still unclear on the runoff and sediment variations of the watershed in the red soil region of southern China, especially after a continuous soil erosion control. This study aims to investigate the characteristics of runoff and sediment in the small watershed after the long-term soil and water conservation in the red soil region of southern China. The Zhuxi watershed in Changting County Fujian Provence was taken as the study area to collect the rainfall and hydrological data from 2017 to 2020. A systematic analysis was implemented to determine the runoff and sediment relationships of the flood events using redundancy analysis (RDA), multiple stepwise regression equations, and sediment concentration (C)-discharge (Q) hysteresis loop methods. The results showed that: 1) The monthly average runoff and sediment concentration were consistent with the trend of monthly rainfall changes during the study period. The annual flood runoff depth and sediment yield were 282.30-892.50 mm and 35.80-179.50 t/km², respectively. The sediment modulus of the flood events was distributed mainly in 0-20.0 t/km². But the total flood sediment yield were determined by a few flood events with the sediment modulus greater than 5.0 t/km². 2) Rainfall (P), the maximum rainfall intensity of 30 min (I30), and rainfall erosivity (R) were the main rainfall characteristics that affected the runoff and sediment. However, the contribution rates of rainfall characteristics to the variations of runoff and sediment were 68.99% and 49.28%, respectively. It infers that the rainfall characteristics were more closely related to the runoff indicators than to the sediment indicators. The runoff was the most important influencing factor of sediment. Thus, the great fitting was achieved in the R² range of 0.624-0.870 with estimating the sediment yield (S), average sediment concentration (Cm), and the maximum sediment concentration (Cmax) of flood events using main runoff indicators, including the runoff depth (H), average discharge (Qm), and peak flow (Qmax). 3) There were six types of C-Q hysteresis loops in the flood events with the sediment modulus greater than 0.1 t/km². Among them, the occurrence frequencies of the single-valued and complex loop were 55% and 22%, respectively. The counterclockwise loop was more appeared in the flood events with the small sediment modulus. The highest occurrence frequency was found in the single-valued loop. The variation of C with Q in the single-valued flood events was characterized by the phased method. The critical C value was about 0.1 g/L, as the C-Q relationship changed. The sediment carrying capacity of runoff was significantly changed at a sediment concentration of about 0.1 g/L. Moreover, the single-valued loops were also dominated in the C-Q hysteresis loop for the large-scale flood event in the watershed. There were the low sediment yields of the flood events and the great influence of the runoff on the flood sediment in the watershed of the red soil region after a long-term soil erosion control. The sediment supply of the flood events, including the large-scale flood events, in the watershed was generally in a continuous and limited state. The findings can provide the much more comprehensive understanding of the runoff and sediment processes in the watershed with continuous soil and water conservation, in order to reveal the development of soil erosion in the red soil region of southern China. [ABSTRACT FROM AUTHOR]

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

BiFe1-xZnxO3 (BFZO) (x = 0, 2%, 4%, 6%) thin films were successfully prepared on Pt/Ti/SiO2/Si substrates by sol-gel method. The effect of Zn doping on the structure, surface morphology, leakage current density, ferroelectric and ferromagnetic properties of BiFeO3 (BFO) thin films were investigated systematically. XRD patterns show that all samples match well with the perovskite structure without impurity phase. SEM images show that BFZO thin films with x = 4% exhibit uniform fine grains and higher density, which is instrumental for the improvement of leakage current density. The leakage current density curve shows that BiFe0.96Zn0.04O3 thin films have the lowest leakage current density (J = 1. 56 x 10-6 A/cm²) under the electric field strength of 300 kV/ cm, which is three orders of magnitude lower than that of pure BFO thin films. Furthermore, BiFe0.96Zn0.04O3 thin film exhibits the largest remnant polarization (2Pr = 20. 91 μC/cm²) at room temperature, which is more than four times as large as that of pure BFO (2Pr = 4. 96 μC/cm²). Additionally, compared with BFO thin film, Zn doping also enhances the ferromagnetic properties of BFO thin films, and as Zn doping concentration increases, the saturation magnetization of BFZO thin films is significantly enhanced, which provides potential applications in information storage. [ABSTRACT FROM AUTHOR]

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

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

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

Tunnel excavation, mining and other projects involve the phenomenon of periodic compression and tension of rock stress. The mechanical effect produced by construction conditions has a significant impact on rock structure. In order to study the deformation and failure characteristics of rock under different loading and unloading rates, the cyclic load test of sandstone at different loading and unloading rates under uniaxial conditions is designed. Based on tie stress-strain curve, hysteresis loop and residual strain, the evolution law of damage, instability and deterioration of sandstone rock mass under cyclic load is deeply analyzed. The results show that compared with the monotonic loading condition, the cyclic load can strengthen the peak stress of rock samples. The residual strain of banner cyclic load is related to the number of cycles in a logarithmic function. In the graded cyclic load, the change of the upper limit stress to the strain is greater than that of the lower limit stress to the strain. The fitting result of residual strain and cycle times is a linear correlation function with the same slope. The loading mode has a certain influence on the elastic modulus of rock samples, and the same loading and unloading rate has the greatest influence on it. [ABSTRACT FROM AUTHOR]

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

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

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

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

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

Aiming at the requirement of the nondestructive testing experimental platform for ferromagnetic materials, an experimental device for testing magnetic parameters of ferromagnetic materials based on hysteresis loop method is designed. The device is an embedded hardware platform, including 7 modules of master control and signal generation, power amplifier and induction signal conditioning, etc. and the application software of magnetic parameter detection is developed to realize data communication, interface display, data management and other functions. According to the experimental results of magnetic parameter detection of CR12MOV steel plate, the device can draw hysteresis loop to obtain the coercivity and remanence parameters. The device integrates multi- disciplinary characteristics and provides an effective comprehensive experiment and practice platform for the construction of the nondestructive testing professional laboratory. [ABSTRACT FROM AUTHOR]

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

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

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

The performance of piezoelectric actuator ceramics under strong electric field(20 kV/cm) and variable temperature (30~150℃) were tested on a piezoelectric ceramic thermo-electro-mechanical multi-field loading test bench. The variation of hysteresis loop, strain loop, free capacitor and dielectric loss tangent with temperature was analyzed. A mathematical model of displacement characteristics of ceramic materials considering temperature effect is established, and the accuracy of the model is verified. The results show that the hysteresis loops become slender with the increasing of temperature, while the residual polarization, maximum polarization and coercive field decrease. The effect of the temperature on the residual polarization and coercive field is stronger than that on maximum polarization. The strain loop presents a typical butterfly curve, and the negative strain decreases gradually to 0.12% with the increasing of temperature. In the unipolar electric field, the residual polarization varies slightly with the increasing of temperature, and the maximum polarization increases about 40%. The piezoelectric constant of the material increases linearly. The free capacitor and dielectric loss tangent increases continuously. The higher the temperature, the greater the increase.

A solar-powered unmanned aerial vehicle generally encounters the problems that it has low Reynolds effects and is highly susceptible to gust response. Therefore, the grid velocity method was used to analyze the gust response characteristics of the airfoil FX63-137 under low Reynolds number. First, the reliability of the numerical simulation method at low Reynolds number and grid velocity method were verified with experimental data. Second, the gust response characteristics of FX63-137 airfoil under different Reynolds numbers and different angles of attack were numerically simulated. The results show that the magnitude of incremental lift coefficient in gust response decreases because laminar separation bubbles are complete as the Reynolds number decreases at a small angle of attack. They also show that laminar separation bubbles have an unloaded effect on gust response. At a high angle of attack, as the airfoil enters into stalling stage, the incremental lift coefficient begins to decline before reaching maximum gust disturbance. Because of the stalling of the airfoil, when the gust disappears, the incremental lift coefficient has a negative value. What's more, although the effective angle of attack is equal, the flow structure of the airfoil is somewhat different in upstream and downstream moments. Compared with the downstream moment, the incremental lift coefficient at the upstream moment is generally larger, and the incremental lift coefficient curve of the airfoil forms a non-closed hysteresis loop.

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

To explore the effect of carbon nanofiber (CNF) doping amount on the temperature resistance effect of carbon fiber reinforced polymer(CFRP), the CNF conductive particles were uniformly dispersed in the epoxy resin matrix, and the CFRP components with different doping amounts were fabricated by the brush molding process. A cyclic temperature test was conducted, and the resistances of the CFRP component were recorded. The results show that all components have positive temperature coefficient (PTC) effect and have excellent linear relationship between temperature and resistivity during the heating process. When the amount of CNF is 0.5%, it is close to the percolation threshold of material, and the temperature sensitivity of component is the strongest.Under the cyclic temperature loading, the temperature curves change in the same trend, but it presents significant "hysteresis loop" phenomenon.As the number of cycles of temperature loading is increased, the temperature sensitivity of the component is decreased, while the repeatability becomes better. [ABSTRACT FROM AUTHOR]

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

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

In order to improve the magnetic and mechanical properties of Finemet alloy, the alloy was heat treated by transverse magnetic annealing to study the effect of annealing process on the magnetic and mechanical properties of the alloy. The Fe73.5Cu1Nb3Si15.5B7 amorphous alloy with wide application in the market is used. The object was subjected to a magnetic field heat treatment by using a transverse magnetic annealing furnace. The crystal phase structure of the sample was measured by an X-ray diffractometer, a SQUID-VSM instrument, and a nanoindenter, and the magnetic properties and mechanical properties were shown. Nanocrystals were formed in the Finemet alloy amorphous ribbon after the transverse magnetic heat treatment, and the hysteresis loop became flat. As the annealing temperature increased, the plasticity deteriorated, but the hardness increased [ABSTRACT FROM AUTHOR]

Using chitosan (CS), citrate (CA), and acrylamide (AAm) as raw materials, a two-step method was used to prepare the chitosan-citrate/poly acrylamide (CS-CA/PAAm) double-network hydrogel, and the rheological properties, mechanical properties and micro-morphology of the hydrogel with different PAAm contents were analyzed and characterized. The results showed that when the PAAm content was 34.6%, the storage modulus of the hydrogel was up to 50 kPa, and the briitle hydrogel became a flexible hydrogel with an elongation at break of up to 110% and a compressive deformation capacity of 90%. And under the condition of 60% strain, there were almost no hysteresis loops after cyclic compression 3 times, showing good rheological and mechanical properties. The hydrogel had a more dense and porous microstructure. With the introduction of PAAm (0 ~ 34. 6%), the swelling rate of the hydrogel was reduced from 644% to 84%, and the swelling equilibrium time was shortened from 54 h to 25 h. The hemolysis rate was less than 5%, which met the national standard requirements and had good safety. [ABSTRACT FROM AUTHOR]

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

In this work, harmonic loss and magnetostriction of thin gauge grain-oriented silicon steel (0.23 mm) were studied by simulating the invigorative magnetic field of 3-7 th harmonic superposition conditions. Meanwhile, evolution law of magnetic domain structure of the material was also explored. The results indicate that harmonic superposition could result in increases of hysteresis loop area and number of hysteresis cycles, as well as change reinforce of magnetic flux density in the samples. Magnetic hysteresis loss and eddy current loss increased continuously with enhancement of harmonic frequency or content, which brought sizeable addictional loss to the sample. Iron loss under 30% harmonic superposition of 5th harmonic increased by 89.7% compared with fundamental frequency. Harmonics caused decreases of width of 180°magnetic domains which could result in decreases of valume fraction of 90°domains and increases of magnetostrictive amplitudes λp-p. At the same time, the butterfly curves were distorted. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

One of the problems in the analysis of the dynamics performance of off-road vehicles is the effect of the accuracy of the hydro-pneumatic suspension model. However, the accuracy of the model for the polytropic process of nitrogen in the gas-charged hydraulic accumulator is one of the key factors, which affects the accuracy of the model for the hydro-pneumatic suspension systems. The traditional approach based on the energy equation and the Benedict-Webb-Rubin equations deduces the well-known thermal time constant model. However, researchers indicate that the thermal time constant varies with the change in the accumulator size and operating cases. Other researchers attempt to modify the polytropic exponent to model the real gas behavior, but the hysteresis loop representing the energy losses in a cycle can’t be described because the polytropic exponent is treated as a constant value. In this paper, an attempt was made to describe the hysteresis loop by adopting a variable polytropic exponent. On the accumulator rig, some tests excited by the sinusoidal displacement with four different amplitudes and frequencies respectively were carried out. The plots of the gas pressures versus the gas volume ratio and the gas volume rate respectively were made according to the experimental data from the accumulator test by using the Matlab software. A comprehensive analysis of experimental data showed that the relationship between the gas pressure and both the volume compression ratio and the volume compression rate were very close. To analyze the relationship between the polytropic exponent and the two parameters respectively, the formula of the polytropic exponent was deduced based on the ideal gas approach and polytropic processes. By substituting the experimental data from the accumulator test into the formula, the plots of the polytropic exponent versus the two parameters respectively were also made. The plots illustrated that the polytropic exponent was closely proportional to the two parameters, respectively. Based on the analysis, a novel method was proposed to build a polytropic exponent model with the two parameters to describe the real gas behavior. In order to verify the correctness and the accuracy of the proposed polytropic exponent model, the two coefficients in the model were identified by using the experimental data from the previous accumulators test, and the coefficient of the volume compression ratio in the model (k1) was 2.4 for the test accumulator, and the coefficient of the volume compression rate (k2) was 1.5. Moreover, substituting the values of the two parameters, which were determined by the different operating cases, into the proposed polytropic exponent model with the two identified coefficients gave a comparison with these experimental data. Furthermore, a co-simulation model, which was based on the polytropic exponential model, for six hydro-pneumatic suspension systems was built to check the application of the polytropic exponent model in the hydro-pneumatic suspension systems of the overall vehicle. And a platform for the hydro-pneumatic suspension systems of the overall vehicle invented and designed by our laboratory, which was the first platform with the capability to test the comprehensive characteristics of multiple suspension systems, was used to test the rolling characteristics of the six hydro-pneumatic suspension systems. Several tests were carried out under the sinusoidal displacements with four different amplitudes and frequencies, respectively. The comparison of the co-simulation results and experimental data showed that the average discrepancy was equal to 5.12% and the maximum discrepancy was less than 10.9%. Therefore, a good correlation was achieved. It further demonstrated that the proposed polytropic exponent model can describe the behavior of the real nitrogen in the accumulator. But the proposed model should be further verified by using more experimental data from much higher frequency tests, and the influence of dissipated energy on the two coefficients in the proposed model should be explored. [ABSTRACT FROM AUTHOR]

Total strain range controlled low cycle fatigue (LCF) experiments were conducted at 750 ℃ to investigate the effects of the duplex and fully lamellar microstructure on fatigue behavior and life of a TiAl alloy, and the total strain range-life equation was employed to predict LCF life of the alloy. The results show that the mean stress produced at hysteresis loop of TiAl alloy with DP is less that of TiAl alloy with FL at the same temperature and applied strain. The total strain range-life equation is able to predict the fatigue life of the alloy, and the predicted life is located between ±2 scatter band of the experimental life. In addition, the fatigue source of TiAl alloy with DP is located near center of the specimen while that of TiAl alloy with FL is located on subsurface of the specimen, and the failure mechanisms are obviously different between the two types of the TiAl alloy.

Al2O3, SiO2 and ZnO were coated around nano-sized BaTiO3 particles by means of aqueous chemical coating. Then, BaTiO 3 -based energy storage ceramic material with average grain size of 120 nm was fabricated by the two-step sintering method. The coating layer can restrain grain growth and abnormal grain growth, and can enhance significantly the AC breakdown strength of the material to over 150 kV·cm-1, while providing energy density of 0.829 J·cm-3. Energy-dispersive spectroscopy proves the gathering of doping elements near grain boundaries, thus indicating the existence of a core-shell structure. High-temperature impedance spectroscopy and fitting results further explain that the energy storage properties were improved. Although the energy density of this ultrafinecrystalline ceramic material is moderate, the advantages of fine grains and low sintering temperature make it possible for the material to be used in multilayer ceramic capacitors, which can increase energy storage by orders of magnitude. This improvement is impossible to achieve with conventional energy storage ceramics.

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

In order to improve the smoothness and rapidity of the inspection robot in turning and slope conditions, a differential controller is designed. The front wheel controls the speed for steering and the rear wheel for the drive function. Among them, the current loop is the hysteresis control and the speed loop is adaptive fuzzy PI control. The hardware and software of the simulation inspection platform adopt modular design. The simulation experiment is carried out in the MATLAB environment, and the experiment is verified on the simulation platform. The results show that the system has a good running effect. [ABSTRACT FROM AUTHOR]

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

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

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