Three dimensional porous scaffolds for tissue engineering were fabricated by freeze drying a blend suspension of cellulose-nanofibers (CNFs) with poly (vinyl alcohol) (PVA), while the Influences of the concentration of CNFs suspension, the mass ratio of CNFs to PVA, the relative molecular mass (mass average) of PVA and the frozen temperature on the morphology and mechanical properties of the scaffolds were investigated. The results showed that: the scaffolds made of CNFs with high molecular mass (mass average) PVA displayed morphology of interconnected pores with irregular open pore geometry; PVA formed the wall of the big pores and which were bridged each other by CNFs bundles of 100-200 nm in diameter to form nest-like structure on the surface of the PVA wall throughout the scaffold, which was similar to collagen skeleton in extra cellular matrix (ECM); the optimal parameters for the fabrication of scaffolds with outstanding nest structure and abundant microfilaments are: mass fraction of CNFs to PVA was 1: 2 and the freezing temperature was -80℃. PVA played a key role in providing the mechanical strength of the scaffolds. The compressive modulus of the supports increased with the increasing amount of PVA, and it was equivalent to that of cartilage tissue, a magnitude of kilopascal, and besides, the mechanical properties of the scaffolds can be adjusted by changing the amount of PVA.

Zr-Al-Cu-Ni-Ag bulk metallic glass (BMG) composites, which consisted of an amorphous matrix and embedded nanocrystallites, were prepared by isothermal annealing the Zr-Al-Cu-Ni-Ag in supercooled liquid regions. The micro-hardness of the composites was measured by Vickers indenter and the morphologies of shear bands formed due to indentation were investigated by scanning electron microscopy. The results indicate that the primary phase during annealing is icosahedral phase (I-phase) and the crystallization volume fraction monotonically increases with the increasing of annealing temperature. The micro-hardness increases with the increasing of crystallization volume fraction, while the density of shear band decreases, which are the results of structure relaxation and the precipitation of nanocrystallites.

Influence of post annealing on the microstructure of hot dip aluminum coating on 45 steel was investigated. The wear properties of HDA steel after diffusion annealing at 1000℃ was also examined. Results show that HDA coating consisted of brittle phase Fe₂Al₅ as the diffusion annealing temperature was below 900℃, however which tranformed to ductile phase FeAl and Fe₃Al at 1000℃and the coating exhibited a structural integrity and good bond with the substrate. The wear rate of the coating annealed at 1000^oC dropped significantly as the environment temperature increased from room temperature to 200℃ and 400℃, reaching an extremely low level. At room temperature, the wear rate rapidly increased with loads. At 200℃ the wear rate hardly changed with loads; the average wear rate was 4.2×10^-6 mg/mm. At 400℃ under the loads of 50 –200 N, the wear rate was lower than that at 200℃ under the corresponding loads. HDA steel presented excellent wear resistance at 200–400℃, owing to a 1–2 μm thick tribo-layer formed on the worn surface, mainly composed of Al₂O₃, Fe₂O₃, and a bit of oxides of W and Mo. In this case the coating suffered mainly from oxidation and slight wear. However, at 400℃ as the load increased to 250 N, the tribo-layer peeled off because of which became unstable , thereby the coating spalled off, and the substate was plastically extruded.

The as-deposited CuIn_1-xGa_xSe₂ (CIGS) thin films were fabricated by magnetron sputtering from a quaternary CIGS target, and then the as-deposited films were annealed in a temperature range from 240℃ to 550℃. The effect of the annealing temperature on the electric properties (carrier concentration and carrier mobility) of the films was investigated in particular. The results show that when the annealing temperature was lower than 270℃, the highly conducive CuSe phase existed in the films leading to a high carrier concentration (10¹⁷-10¹⁹ cm^-3) and a low carrier mobility (~0.1 cm²V^-1s^-1). These films are not suited for CIGS absorber usage. When the annealing temperature was higher than 410℃, the carrier mobility of the films was high about 10 cm²V^-1s^-1 and the carrier concentration was in a range of 10¹⁴-10¹⁷ cm^-3 due to the disappearance of the CuSe phase. When the annealing temperature was higher than 410℃, with the increase of the annealing temperature the grains grew larger and the crystallinity of the films was enhanced, which could reduce the defects in the films and result in the decrease of the carrier concentration. From the aspect of the carrier concentration and the carrier mobility, the appropriate annealing temperature for fabricating the absorbers of the CIGS solar cells is from 450℃ to 550℃.

According to the principle of bilaterally matching in microstructure and composition for a weld joint to a matrix alloy, a self-shield flux cored wire was made of 304 stainless steel plate as feed metal with a selected flux especially for welding of FV520 (B) martensite stainless steel. Then FV520 (B) martensite stainless steel was welded with the prepared flux-cored wire by adopting appropriate welding process parameters. The weld joints were characterized in terms of microstructure and mechanical performance. The results show that the weld joints possess excellent mechanical properties: such as a tensile strength up to 911 MPa, a yield strength up to 679.3 MPa and an impact energy value 99.7 J (20℃).The microstructure of the weld joints consisted of tempered sorbet and lath marten site, as well as a little residual austenite and carbide precipitates, which can match well with parent material.

The fatigue behavior of A319 cast aluminum alloy was investigated in terms of its cycle stress response characters and fatigue life under a 0.2% strain amplitude with several loading paths, such as uniaxial, proportional and non-proportional ones. While the fracture characters of failed specimen and the cracking modes of Si particles were also investigated. Under the condition of same equivalent stress, the effectiveness of the three loading paths on the hardening of the alloy in terms of the degree and rate of hardening may be ranked in an order of high to low as follows: non-proportional > proportional > uniaxial, corresponding with the fatigue life exactly. The fractography of the alloy presented two major cracks with the herringbone pattern under the proportional loading. Additionally, the crack initiation site was gradually blurred when the loading path changing from uniaxial, to proportional and then to nonproportional ones, in the meanwhile the size of the crack initiation site and propagation region also decreased. The crack surface basically paralleled to the loading direction under uneasily loading, however, multi-cracks with different directions occurred under multi-axial loading.

Hollow microspheres of Zn_xCo_1-xFe₂O₄ were synthesized by ultrasonic assisted solvothermal method. The microstructure and morphology of synthesized microspheres were characterized by X-ray diffraction (XRD) and transmission electron microscope (TEM). The results show that hollow microspheres of Zn_xCo_1-xFe₂O₄ show cubic crystallographic structure which indicated that the doping of Zn²⁺ had no effect on the crystal type, but it induced change in the size of the microspheres. The average diameter for hollow microspheres of CoFe₂O₄ and Zn_0.5Co_0.5Fe₂O₄ were 50 nm and 200 nm respectively. The performance of magnetism and microwave absorbing of the microspheres were investigated by a vibrating magnetometer(VSM) and a network vector analyzer respectively. Results show that with the increasing of Zn²⁺ content, the saturation magnetization of the Zn_xCo_1-xFe₂O₄ hollow microspheres increased slightly and then decreased, while the coercive force decreased. When x=0.3 the Zn_xCo_1-xFe₂O₄ hollow microspheres exhibit the best performance both in magnetism and microwave absorbing.

By using polycarpolactone (PCL) and polyvinylpyrrolidone (PVP) as raw materials, a series of nanofibrous scaffolds were fabricated by thermally induced phase separation in a dioxane/water system. The effect of aging temperature, PVP content and different ratios of dioxane to water on the morphology of nanofibrous scaffolds was investigated. The effect of PVP content on the biological activity and hydrophilic performance of the prepared nanofibrous scaffolds were also examined. The results show that aging process played a crucial role in forming the unique nanofibrous structure. The solvent system and the PVP content affect the nanofibrous structure, peculiarly; the nanofibrous structure would disappear gradually with the increasing PVP content. The result of the water absorption shows that the hydrophilic performance of the nanofibrous stent increases with the increasing PVP content. Furthermore, the test of biological activity shows that there exists crystallite carbonate hydroxyapatite in the scaffolds, indicating that the PCL/PVP nanofiberous scaffolds have a good biological activity, and which may much rapidly facilitate the forming of crystallite carbonate hydroxyapatite rather than the merely PCL ones.

The compatibility of lithium di?uoro(oxalato)borate (LiODFB) electrolyte with LiNi_0.5Mn_1.5O₄ as high-voltage cathode material was investigated by cyclic voltammetry, charge-discharge test and AC impedance. The results show that the LiNi_0.5Mn_1.5O₄/Li half cells with LiODFB or LiPF₆ as electrolyte all have simple REDOX peak at 25℃ and 60℃, and the battery has an excellent reversibility. The battery with LiODFB has better cycle performance than that with LiPF6 at 25℃ and 60℃. Their 0.5C initial discharge specific capacities at 25℃ are 126.3 mAh?g^-1 and 131.6 mAh?g^-1, and the capacity retention ratios by the 100th cycle are 97.1 % and 94.7% respectively. The 0.5 C initial discharge specific capacities at 60℃are 132.6 mAhg^-1 and 129.1 mAhg^-1, and capacity retention ratios by the 100th cycle are 94.1% and 81.7% respectively. AC impedance plots also show that the battery with LiODFB has a lower charge-transfer resistance than that with LiPF6 at 60℃, indicating that the battery with LiODFB has excellent cyclic performance at high temperature.

Taking dimethyl terephthalate (DMT), 1, 4 - butylene glycol (BG) and polytetrahydrofuran (PTMG) as main raw materials, a series of PBT/PTMG poly(ether ester) thermoplastic elastomers were prepared with catalysts of tetrabutyl titanate, tetrabutyl titanate/magnesium acetat, tetrapropyl-zirconium and zinc acetate/antimony trioxide respectively. The effect of catalysts on the transesterification rate of the synthesis process, the molecular weight distribution, crystallinity, mechanical properties and heat resistance of the synthesized materials were mainly concerned. The synthesized thermoplastic elastomers were characterized by means of SEM, GPC, DSC, TG and mechanical testing. The results show that: while taking tetrabutyl titanate/magnesium acetate as catalyst, with the increasing amount of the catalyst, the transesterification rate increased, and the molecular weight and crystallinity increased, the molecular weight distribution index decreased, the toughness enhanced and the thermal decomposition temperature was above 390℃ for the synthesized thermoplastic elastomer.

Y-TZP/ LZAS glass-ceramic gradient coatings on Q235 steel substrate were designed. The effects of compositional exponent, the number of graded layers and coating thickness on the residual stress were analyzed by using finite element software. The results show that the optimal coating could be obtain corresponding to the following parameters: the compositional gradient exponent m＝1, the number of graded layers= 3-5 and the coating thickness=1.0-1.5 mm. The radial compressive stress distributes on the surface of gradient coatings. There is clear stress concentration in the coating/substrate interface. The compositional exponent, layer numbers and the coating thickness have important influence on the radial stress, axial stress and shear stress in the coating/substrate interface. Y-TZP/ LZAS glass-ceramic gradient coatings were fabricated on Q235 steel substrate by slurry method. The residual stress of gradient coatings was measured by X-ray diffraction approach and the measurement results verified the reliability of the above simulation.

Organoclay/polyethersulphone/epoxy hybrid nanocomposites were prepared by solvent method and melting method, respectively. Their tensile properties, fracture toughness, thermal properties and microstructures were then characterized. Their tensile strength arrived at 75 MPa, modulus reached 2.8GPa, and fracture toughness was over 1.1MPam^1/2. Synergistic toughening effect of the polyethersulphone and organoclay on the epoxy resin was observed. Semi-interpenetrating network of the polyethersulphone/epoxy matrix was found by dynamic mechanical thermal analyzer (DMA) and transmission electron microscope (TEM). The results of X-ray diffractometer (XRD) analysis and TEM observation reveal that the organoclay possessed ordered exfoliated morphologies. Glass transition temperatures (Tgs) of the two hybrid nanocomposites were tested by dynamic mechanical thermal analysis (DMTA). The T_g of the specimen prepared by the solvent method was found higher than 170℃, while that by the melting method was more than 180℃.