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In this paper, chitosan and caffeic acid were used as starting materials to prepare chitosan caffeates by reflux-heating and freeze-drying. The structures of chitosan caffeates were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and potentiometric titration. At the same time, the physical properties of chitosan caffeates were tested and the hemostatic properties were evaluated. The results showed that four chitosan caffeates with different mass ratios of chitosan and caffeic acid (1:1, 1:2, 1:4, 1:6) had been successfully prepared, which enhanced the water solubility. FTIR analysis demonstrated that caffeic acid had been successfully grafted onto chitosan chains. XRD showed that the crystal form of chitosan changed to some extent and the chain had some regularity in some directions, but its crystallinity reduced. Chitosan caffeates, particularly mass ratio of 1:1, showed excellent hemostatic properties and even better than chitosan and the positive control (Yunnan Baiyao), which were expected to be developed as an effective biomaterial for hemostasis.

This study proposed the new method of preparing Mg-based composite by mixed powder Ni and Ti onto the surface of pure Mg ingot. The prepared method caused that hydrogen absorbing phase Mg2Ni and catalytic phase NiTi generated and distributed regularly. The pure Mg ingot as the center and the powder Ni and Ti as cladding material on the surface were formed and sintered, in which the temperature range of generated alloy phase Mg2Ni and NiTi was confirmed at first; according to the temperature range, the size of Mg2Ni and NiTi crystal grains at 650°C and 850°C were analyzed and compared, respectively; The size of Mg2Ni alloy phase at the surface and center was calculated by comparing the atomic radius of Ni, Ti to confirm that Mg2Ni distributed on the surface due to the atom Ti replaced the atom Ni in Mg2Ni to generate the alloy phase NiTi; the capacity of the hydrogen desorption reached 4wt% within 5min. The disadvantages that easy to chalking and difficult to activate in the conventional method were avoided and achieved the application of the multilayer composite material in hydrogen storage field.

Mg-based alloys were prepared by rapid solidification of twin roll casting (TRC) which shows that the Mg-RE alloy expressed the quasi-amorphous phased and fine crystalline phase dual-phase material. Corrosion behavior of Mg-Based alloy in 3.5% NaCl solution after 48h immersion and mechanical properties were investigated. The result show that The Mg-RE alloy strip exhibited good corrosion resistance and higher ultimate tensile strength and elongation comparing to the AZ31 alloy strips. The elongation of Mg-RE alloy strip is also high than the AZ91 and ZK61 under powder metallurgy processing. These indicate that Mg-RE alloy produced by our method has a better ductility. This may due to the special microstructure of the Mg-RE alloy forms, i.e., quasi-amorphous phase plus fine crystalline phase dual phase state.

In this study, magnesium alloy AZ31 was successfully welded with aluminum alloy 6061 by diffusion bonding method. In addition, annealing process was applied to refine micro-structure and improve mechanical property. Microstructure and elemental distribution of interface were investigated with Scanning Electron Microscope (SEM) and Electron Probe Micro Analyzer (EPMA). Furthermore, experiments on diffusion bonded specimens with the usage of Transmission Electron Microscope (TEM) were carried out. At last, tensile strength was measured. It can be obtained that the width of diffusion layers increase with the increasing annealing temperatures. Elemental distribution of specimens with annealing were more uniform than that without annealing. The intermetallic compounds in diffusion layers are Al3Mg2 and Al12Mg17, their crystal structure are respectively face-centered cubic (fcc) and body-centered cubic (bcc). What’s more, tensile strength turns to be strongest after annealing at 250°C.

In this study, Mg-based alloys were prepared by rapid solidification of twin roll casting (TRC), then microstructure and element distribution were investigated respectively with Scanning Electron Microscope (SEM) and Electron Probe Micro Analyzer (EPMA). What’s more, in order to analyze microstructure and crystal structure of Mg-based alloys, experiments on specimens with the usage of X-ray diffraction (XRD) and Transmission Electron Microscope (TEM) were also carried out. At last, the designed Mg-Re magnesium alloy with quasi-amorphous phase plus fine crystalline phase dual phase microstructure produced with our rapid solidification of TRC process. The rapid solidification process realized with a faster casting speed and a thinner roll gap that does not need any anther additional devices and vacuum environment. EPMA results and TEM analyses show that the quasi-amorphous phase has a high concentration in Al and RE element. There are quasi-amorphous phase in the middle of Mg-Re alloy cross section surrounded by dendrites phase and normal crystals. Acknowledgement. This work was supported by Cooperative Research and Development Center for Advanced Materials (CRDAM) funded by the Institute for Materials Research (IMR), Tohoku University (Project Number 18G0042).

Magnesium alloy is honored as green engineering material for its low density, high specific strength, high specific rigidity, well cutting processing property, well electromagnetic shielding property, heat conduction and easy to recycle. In this paper, AZ31 Magnesium alloy sheet at difference thickness were prepared by symmetric and asymmetric rolling employed with six-roller mill. Microstructure of the two kinds of rolling magnesium alloy thin sheets at 0.5mm thickness were investigated. The grain distribution of AZ31magnesium alloy sheets made by asymmetry rolling at room temperature are more uniform than those made by symmetry process. The grains made by asymmetry are more tiny and the tensile strength and elongation increased obviously and the mechanical properties got better. At room temperature, value of n increased. Large value of n benefit to stamping forming. At room temperature, the value of LDR of asymmetry rolling sheets is 1.26, which was higher than symmetry rolling. So asymmetry rolling benefits to stamping forming.

Phase field method (PFM) was employed to investigate the crystal growth of Mg-Al alloy, on the basis of binary alloy model, the fluid field equation was coupled into the phase-field models, and the marker and cell (MAC) method was used in the numerical calculation of micro structural pattern. In the cast process, quantitative comparison of different anisotropy values that predicted the dendrite evolution were discussed in detail, and when the fluid flow rate reaches a high value, we can see the remelting of dendrite arms.

According to the electromagnetic pump in Magnesium Alloy Casting Experiments Center of University of Science and Technology Liaoning, with the help of ANSYS software, we realized three-dimensional simulation of electric field of the pump by finite element analysis method, and calculated the distribution of electric field generated by five data sets , whose slot length and width were 30mm, 50 mm, 60 mm, 70 mm and 80 mm. We have explored how different runner dimensions affected electric field distribution in electromagnetic field, and simulated the distribution of current density. The optimal size of the runner is 50mm according to the current density distribution.

A numerical simulation method is used to predict the depth distribution of martensite and hardness in the case layer of carburizing (carbonitriding)-quenched 20CrMnTi steel. Microstructure and mechanical properties of 20CrMnTi steel after carbonitriding and subsequent induction hardening is investigated. The results show that the microstructure after nitriding and subsequent induction hardening is main tempered martensite and nitrides; after carbonitriding and subsequent induction hardening is main martensite and a small amount nitrides. The simulation results were a little different from experimental results. According to the results, the factors of reducing the accuracy of the numerical simulation method have been discussed.

A layer of Mo (Si,Al)2 was prepared on the sample surface of Mo substrate by powder coating method using Al-Si mixed powder and then diffusion reaction in argon atmosphere at 900°C. The results of oxidation resistance showed that the Mo samples coated with the Mo (Si,Al)2 layer had an excellent oxidation resistance in air even at 1200°C. The reason of oxidation resistance is the formation of a dense alumina film on the sample surface. Therefore, the further oxidization of the sample can be prevented. In addition, The formation of Mo5(Si,Al)3 layer was also observed at the interface between the Mo substrate and the Mo (Si,Al)2 layer.

In this paper, the stiffness compensation is used in the roll-gap controller to improve the reliability of the control system. Simulation research indicates that this method can enhance the control quality than traditional control strategy.

In the twin roll strip casting process, the control for the molten metal level is difficult owing to non-linear and time-varying of the control parameters. In the paper, on the basis of the geometry shape of the molten metal pool and the continuity of metal, the level mathematic model is built. Then a fuzzy control strategy is adopted to control the level. Moreover GA(Genetic algorithm) is used to obtain better fuzzy parameters. Simulations show the fuzzy controller optimized by GA greatly improves the control performance.

In order to develop a new air cell cathode, the mixed with Mg alloy and zinc powder as anode material of a kind of button battery was proposed in the research work. In this paper, the ion concentration results of corrosion solution by ICP measurement was used electrochemical simulation by FACSIMILE for evaluating mechanism of corrosion reactions for Mg alloy and Zn mixed button cell.

A modified 2-D CA model has been developed to simulate dynamic recrystallization behavior of Magnesium (Mg) alloy during hot deformation processing. Based on the fact that Mg has an HCP crystal structure with six-fold symmetry, the model employs the hexagonal CA lattice. The initial microstructure with prescribed grain size was generated by a normal grain growth algorithm. The DRX model consists of dislocation density evolution model, DRX nucleation model and recrystallization grain growth model. DRX grain morphology and size, flow curve were simulated by the present model. The calculated results were compared with the available experimental findings in AZ31 Mg alloy, the predictions show very good agreement with the experimental results.

In this paper, in order to study the transformation plasticity behavior of steel materials in heat treatment and other heating manufacturing process, experiment and simulation of heat treatment for SUS420J2 were carried out. With the conditions of the experiments and simulation, SUS420J2 steel was heating to the austenite transformation temperature and stress is loaded when the steel rapidly cooled to the martensitic transformation start temperature. The transformation plasticity behavior and influence in the load stress of the heat treatment process are revealed.

Crack initiation and propagation during creep test in a recrystallization (RX) grain containing directionally solidified (DS) nickel-base superalloy was studied by employing electronic backscattered diffraction (EBSD) technique. Creep samples were locally deformed and then heat treated to get local RX at the center of the gauge length. Creep test was carried out at 980 °C/235 MPa. It was found that during creep test, precipitate free zones (PFZ) were formed along the RX grain boundary and the cracks were initiated and propagated along the interface (a) between PFZ and RX grains, (b) between PFZ and the matrix or (c) within PFZ. It indicated that the crack initiation and the propagation were crystal orientation dependent.

The sloshing fluid inside the tank car which is moving influences importantly on the working of the tank car. The user-defined function second development of the software FLUENT was adopted. The force variation of the tank on the front wall under different working conditions was calculated and the reasons of this variation and the influence on the tank were both analyzed. Little influence on the tank by the sloshing fluid was obtained without energy source. When the tank slowed down, the force peak value remained within the first period of the fluid sloshing, which provided the selection of the tank at the accelerating moment with the foundation.

Magnetic fluid (MF) is a new functional material researched in recent years. It has lots of properties such as superparamagnetism, high permeability, first-order and second-order buoyancy principle suitable for sensor application. The sensing properties decide the sensor applications of magnetic fluid. Different application sensors such as pressure differential sensor, acceleration sensor, and angle sensor were demonstrated and the working principles were presented.

Smart card attendance system using Delphi database development technologies and RF card technology development. Function of each sub-module design includes user login module, attendance information management module , a database management module , a database designed to follow the general principles set forth , and then the database structure design concept .

Aiming at the paradox of D-S evidence theory and computations exponential growth in dealing with large scale conflict evidence combination, a new weighted evidence combination method was proposed, which used conflict coefficient and evidence distance in order to measure the conflict. Through the analysis of single conflict representations weaknesses, compound conflict coefficient has been put forward, meanwhile, the evidence center and current center distance were defined, evidence weight was determined with current center distance and conflict coefficient. The experiment results show that the algorithm settles the paradox effectively, at the same time, computing speed has been greatly enhanced.

Aiming at air rolling bearing vibration signals low SNR and nonstationary characteristics, taking wavelet theory and principles of the wavelet noise reduction for air vibration signals of rolling bearings to conduct wavelet noise reduction processing.By means of the simulation signal wavelet noise reduction processing and fast Fourier transform, the contrast analysis of the vibration signals after wavelet noise reduction and FFT transform and the original signal directly to the result of the fast Fourier transform, and thus prove the validity of the vibration signal wavelet noise reduction. Through the actual vibration signals of bearing conductnoise reduction processing, the result is a further indication of the superiority of wavelet noise reduction in eliminate noise interference.

To meet requirements of wider data width, higher throughput, and more flexibility, a specific arithmetic operation core (AOC) is designed for high definition audio application specific processors. The proposed core is capable of processing long bit-width operations, as well as short bit-width operations in parallel. A six-stage pipeline is applied in the architecture of AOC to support amounts of DSP operations, and a novel stage-skipping technique is used to improve the execution efficiency of instructions passing through the deep pipeline. Several DSP kernels and audio data decoding applications are used in performance evaluation of AOC. Experiment results show that the proposed operation core can achieve over 50% higher execution efficiency in audio applications than conventional high performance DSPs, providing an appealing solution for design of operation core for high definition audio applications.

In order to solve the variable speed control as non-linear in wind energy application, it is important to obtain wind energy efficiently. And it is also effective in suppressing output fluctuation. Therefore, it will become a main torque system in the wind generation. The main object of this paper is to present a developed non-contact torque sensor for applying of non-linear control in the wind generator. In this paper, it examines whether efficient torque measurement of output shaft in the wind generation would be maintainable by non-linear control methods.

The study is diffusion bonding of Mg-AZ31 and Al-6061 under pressure and no pressure by using the direct bonding method. After bonding process, characteristics phase in interface and bonding boundaries of Mg-AZ31/Al-6061 were characterized . The diffusion formation was observed by SEM. Aluminum solid solution and Mg17Al12 alloy phase was proved by analysis of XRD. In the process of measurement, crystalline structure of nearby interface characteristics phase was analyzed in detail by TEM. Based on the above analysis, the crystal model of the magnesium alloy and aluminum alloys was established under pressure, and the bonding mechanism was discussed. The results show that the bonding materials could be bonded under no pressure and the structure of bonding interface is more optimized than pressure.

A static aeration biopile process was used to bioremediate polycyclic aromatic hydrocarbon (PAH)-contaminated soil using four different approaches for treating about 30 m3 of soil at a former oil-producing site. The four treatments investigated were as follows: (i) fertilizer plus bulking agent (FB); (ii) fertilizer, bulking agent, plus Tween 80 (FBT); (iii) fertilizer, bulking agent, Tween 80, plus fungi agent (FBTF); and (iv) fertilizer, bulking agent, bacterial inoculum, plus fungi agent (FBBF). After bioremediation for 320 days, the total amount of 16 PAHs ranged from 4.14 to 5.31 mg/kg in the final soil, removal rates ranging from 75.5% to 81.5%. The sum concentration of seven carcinogenic PAHs decreased down to 0.15 mg/kg. The values of the total toxicity equivalence concentrations for 16 PAHs ranged from 0.014 to 0.068 mg/kg. The removal rates of the 16 PAHs in these four different treatments decreased in order FBBF > FBT > FBTF > FB.

A novel solid-solid phase change materials was synthesized by the two-step condensation reaction of polyethylene glycol (PEG1000), neopentyl glycol (NPG) and 4, 4-diphenylmethane diisocyanate (MDI). Polyethylene glycol (PEG1000) was used as soft segment and 4, 4-diphenylmethane diisocyanate (MDI) as hard segment. The composition, structure and phase change properties were characterized by Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), thermogravimetric analyzer (TGA), polarization optical microscopy (POM) respectively. The results indicated that the PCM appeared typical solid-solid phase transition property and the phase change enthalpy and phase transition temperature reached to 120.45 J/g and 37.32°C, respectively.

Monodisperse porous polystyrene microspheres were prepared with the mixed solution of ethanol and water as dispersion medium and poly (vinylpyrrolidone) was used as dispersant. The even size of microspheres prepared at optimal process was about 1μm. Photochromic microspheres were obtained using polystyrene microspheres to absorb the photochromic materials. The effect of dispersion medium on the microspheres morphology was investigated. The adsorption parameters affecting microspheres adsorption quantity, such as the concentration of spiropyran solution and adsorption temperature, were studied in detail. Furthermore, photochromic properties of the microspheres were analyzed and PVA as coating was used to increase the fatigue resistance of photochromic microcapsules. The photochromic microspheres obtained could rapid reversibly change color under UV or sun light at room temperature and common pressure.

Thermal flow finite element simulation was carried out to deeply understand the solidification and deformation phenomena of magnesium alloy in molten zone during twin-roll casting process. The results show that temperature near the nip of the rolls is about 680K based on current conditions, and there are two vortexes in the molten pool during casting, a peak formed at solidus. Due to the metal flows in molten pool and relative rotates of the rolls, temperature field of molten zone is different from normal casting, which will cause the solidification structure changes. An experiment by using a vertical type twin-roll caster was also conducted, and the amount of deformation bands at the joint line is larger than that at the two sides. Substructures can be found due to dynamic recrystallization during casting process.

According to the mathematic model of solar cells, builds its general simulation model based on the S-function designed under the Matlab/Simulink environment. Presents the incremental conductance algorithm based on the optimal gradient to simulate and verify the theories about the maximum power point tracking (MPPT) of photovoltaic power generation. Give the in-depth contrast analysis on the power, output voltage characteristics of photovoltaic power generation, which lays a solid foundation for engineering practice.

In this paper, the established control system and its control algorism of a new twin roll strip caster developed by authors is presented. It is illustrated the roll-gap control strategy of the twin roll strip caster based on a feed forward-feedback system. From the experimental results, the susceptibility of control convergence time, stable and accurate are shown on a higher level than traditional control strategy.

A new method is proposed for mapping of phase distribution in electron holography. A stage-scanning system was used for moving the specimen to obtain a series of holograms with different specimen positions in a fixed electron-optics configuration. By applying a digital aperture which selects an area on holograms with different specimen positions, an interferogram of the specimen can be obtained directly without a complex reconstruction method such as the one using Fourier transformation. Experimental results for a Co particle demonstrated the practicability of this method.

It is well known that the advances in the biomedicinal applications of magnetite nanoparticles were studied recently. As a drug delivery tools, it only affects on the target region of illness. We investigated the application of magnetic nanoparticles as drug delivery tools by the mice model of atopic dermatitis. The results involve that after magnetic nanoparticles are applied to the skin, the condition of atopic dermatitis becomes much better than the former one of atopic mice model. It only affects on the illness region and healthy regions almost have no influence. It is suitable for the medical treatment technique usage on the atopic dermatitis.

In this study, a biaxial tensile test of cruciform specimens containing centre notch was conducted in order to clarify the deformation behavior near the crack tip at the early stages of crack initiation when objected to a biaxial stress state. Results show that the hardness and stress value within the deformed zone increased with increase in the loading ratio. Observation of the microstructure reveals that the deformation is dominated by basal slip under equal biaxial tensile loading. The asymmetrical biaxial tensile loading generates deformation twins near the crack tip. These results indicate that existing deformation twins contribute to higher hardness, and there is obvious anisotropism in the vicinity of crack tip under asymmetrical biaxial tensile loading.

This paper studies mainly the diffusion bonding of 3Y-TZP/SUS304 by using the chemical bonding method. In the bonding interface of 3Y-TZP and SUS304, the Ti-Cu powder/sheet was used as bonding materials. In bonding process, multi-alloy with Fe-Ti and Fe-Cu have been confirmed by Electron Probe Micro-Analyzer (EPMA) determination. Through the microstructure observed by AFM and SEM, bonding boundaries of 3Y-TZP/SUS304 by Ti-Cu powder/sheet had good formation. The distribution of the residual stress on near interface was measured by XRD method. By using of these results, the mechanism of the ceramic and stainless steel was discussed.

In order to study the details of deformation and microstructures evolution during rolling and annealing process, magnesium alloy AZ31 blank, cast by unidirectional solidification and then sliced, has been rolled at high temperature with one pass deduction of 50% in a 2-high mill. During the rolling process, the mill was stopped, and the rolled sheet was rapidly cooled by the cold rolls. Samples with full length of rolling bite zone were cut form the semi-rolled sheet. Because twinning deformation can be reserved even the sample was polished and etched. The continuous changes of microstructure, from entrance to exit of roll bite, both rolled and annealed samples, were evaluated by Optical Microscope (OM), Scanning Electron Microscope (SEM). The results revealed that grain refinement mechanism was twinning intersection which segmented large grains into small pieces. The average grain size is 7µm after one pass 50% reduction hot rolling and 350°C, 15min annealing.

This paper is mainly a study the diffusion bonding of Mg-AZ31/Al-6061 by using the direct bonding method. After bonding process, multilayer field with Mg-Zn and Al-Zn have been confirmed by EPMA determination. Through the microstructure observed by SEM, bonding boundaries of Mg-AZ31/Al-6061 had good diffusion formation. The identification of the component on near interface was measured by XRD method. By using of these results, the mechanism of the magnesium alloy and aluminum alloys was discussed.

A modified two-dimensional (2-D) cellular automaton (CA) model was constructed to simulate dynamic recrystallization (DRX) process of GCr15 steel. Particle stimulated nucleation (PSN) was incorporated into the CA model to determine the influence of dispersed particles on the nucleation of DRX. In addition, the model included the effects of particles on increasing the dislocation density and pinning the grain boundaries for accurate determination of micro-structural evolution during DRX. The model was applied to simulate the DRX process of GCr15 bearing steel. DRX grain size and volume fraction were simulated using the CA model. The simulated results indicated that the simulated stable grain size of particle-containing model is closer to measured value than particle-free model. It was observed that DRX kinetics depends on both thermo-mechanical parameters and initial grain sizes. The calculated results were compared with the experimental findings in GCr15 bearing steel, the predictions show very good agreement with the experimental results.

DLC/SiC films (SiC as a transition layer) were prepared on the surface of magnesium alloy (AZ31) using a plasma immersion ion deposition (PIID) process. A dense and smooth DLC film can be observed by SEM. The surface hardness can be improved to 11.45GPa by deposition of the DLC film. Electrochemical tests show that the corrosion potential of AZ31 with DLC film is increased from -1.7V to -0.6V, which indicates that the DLC film improves the corrosion resistance of Mg alloy.

N-doped TiO2 films were prepared by using N ion beams to bombard TiO2 films surface. By controlling the metal ultrahigh vacuum gat valve, only the N ion beams working pressure was adjusted from 0.1 to 0.9 Pa, with the step size of 0.2 Pa. The composition, chemical bond structure, and optical properties of N-doped TiO2 films were investigated. The result indicated that with increasing the ion source working pressure, more N ions were generated and bombarded with the surface TiO2 films, which could result in more N ions were doped into the films. So with increasing the ion source working pressure from 0.1 to 0.9 Pa, the N/Ti and O/Ti atom ratio increased and decreased monotonously from 0.37 to 0.49 and 1.49 to 0.61, respectively. Meanwhile, because of more N doped into films, the mean absorbency of N doped TiO2 films in the visible range also increased monotonously from 4.8% to 45.8%.

In the present work, Ni/MgO powder was prepared by co-precipitation in which CO restore NiO to elemental subtance Ni due to C2O42- was decompose to CO and CO2 at 700°C. As the process of the second sintering, H3BO3 was added into the sintered powder of 700°C and was grinded. Then the powder of H3BO3 added was sintered at 800°C，so that the powder was refined, obviously. Thermogravimetric analysis (TGA) and differential thermal analysis(DTA) was carried out in CO2 flow at 10°C/min. X-ray diffraction (XRD) was carried out on a X-ray diffractometer operated at 20KV and 40mA. The microstructures and morphologies were studied by EPMA and XPS.

The unidirectional solidification process of magnesium alloy needs to establish a specific temperature gradient in casting mold, the direction of crystal growth and heat flow are in the opposite direction in the unidirectional solidification. The process can better control the grain orientation, and eliminate the horizontal grain boundary, so to attain columnar grain structure and excellent performance of magnesium alloy. In this paper, Numerical simulation is carried out by orthogonal experiments in order to obtain the optimal process parameters according to the actual experimental device. Different process parameters are taken into account, including pulling speed, cooling time and cooling intensity. FEM (finite element method) is employed to calculate the temperature field and reached a straight shape of temperature gradient distribution which is conductive to achieve unidirectional solidification microstructure. PFM(phase field method) is adopted into the microstructure calculation. The microstructure obtained by PFM is in agreement with the actual pattern by the optical microscope observation.

Strategy and function of a new developed FEM code COSMAP(COmputer Simulation of MAterial Process) for surface hardening during of thermo-mechanical processing, including heat treatment, carbonizing and nitriding and induction heat treatment, is briefly introduced in this paper. The simulation code is developed based on the metallo-thermo-mechanical theory considering the coupled equations of magnetic or electrical field, diffusion, heat conduction, inelastic stresses and kinetics of phase transformation. Some examples of simulation and the experimental verification for induction heat treatment, carbonized quenching, carbonized- nitrided-quenching process of a cylinder and ring as well as a gear are illustrated, and comparison of the simulated values of distortion, residual stresses and profile of induced phases with the experimental data is made with some discussions.