Autoclave experiments in different water chemistry were conducted to clarify the degradation behavior of zircaloy--4 corroded in LiOH aqueous solution. It was found that the compressive stress and the tetragonal zirconia ($t$--ZrO$_{2}$) contents in oxide films formed in different media were different; when specimens were exposed in LiOH and KOH solutions with same concentration, the penetration depth is shallower and the intensity of K$^{+}$ is weaker than those of Li$^{+}$, and the penetration depth of OH$^{-}$ corroded in KOH solution is also shallower than that corroded in LiOH solution. Based on the results, it is suggested that the growth of oxide films is a process of OH$^{-}$ diffusing from outside of oxide into metal/oxide interface and reacting with zirconium to form ZrO$_{2}$ and hydrogen. It is easy for Li$^{+}$ to diffuse into oxide film because of small radius when specimen was exposed in LiOH aqueous solution, so more OH$^{-}$ would diffuse into oxide film deeply. The reaction between adequate OH$^{-}$ and oxygen vacancies in the $t$--ZrO$_{2}$ would promote the transformation from $t$--ZrO$_{2}$ to monoclinic zirconia ($m$--ZrO$_{2}$). The transformation would bring some cracks in the oxide, which relaxed the compressive stress in the oxide, degraded the protective ability of oxide films and caused an enhancement of corrosion rate of zircaloy--4 alloy.

A mathematical model of equiaxed grains movement and macro--segregation has been built to analyze the fluid flow and species distribution during the metal solidification. The mushy zone was divided into dendrites region and free equiaxed grains region by the dendritic coherency point. Macro--segregation of a steel ingot in a rectangular mold with a riser was simulated and the calculation result was compared with that of an experiment. It shows that the species distribution obtained by the grain movement model is more consistent with experiment comparing to that by the solid skeleton model in mush. The equiaxed grains move with the fluid and accumulate at the bottom center of the ingot during solidification. The cone--shape negative segregation forms after solidification. The positive segregation in the upper center and the negative segregation in the exterior region of the ingot are found at the same time.

An Al$_{90}$Pb$_{10}$ alloy has been melt-spun into ribbons. As Pb and Al are immiscible at room temperature, the melt--spun ribbons were composed of dispersive nanometer--sized Pb particles embedded in Al matrix. By means of differential scanning calorimetry (DSC) to cycle heating and cooling, the Pb nanoparticles in the melt--spun ribbons undergo three melting--solidifying cycles. Microstructures of both the as--spun and the treated samples were studied by transmission electron microscopy (TEM). It was found that the average size of Pb nanoparticles increased obviously and most of the Pb particles with a size less than 10 nm disappeared after the heat treatment cycles. Meanwhile, Orowan dislocation rings were observed among the grown Pb particles after cycles. That is, Ostwald ripening of Pb nanoparticles occurred in the immiscible Al90Pb10 alloy during the heat treatment cycles. The evolution mechanism of structure and morphology was also discussed.

A simulated occluded cell (O.C.) was used on the study of chemical changes in the local corrosion pits or crevices of archaeological bronze in simulated environment medium (0.028 mol$\cdot$L$^{-1}$ NaCl + 0.01 mol$\cdot$L$^{-1}$ Na$_{2}$SO$_{4}$ + 0.016 mol$\cdot$L$^{-1}$ NaHCO$_{3}$). It is found that the pH value decreases from 7.00 to 5.02 as anodic current passes the cell for 32 hours, meanwhile Cl$^{-}$ and SO$^{2-}_{4}$ migrate into the O.C. and their concentrate rate reachs 6.31 and 2.93, respectively. The metallic ion concentrations of Cu, Sn, and Pb in the O.C. and bulk solution were measured which were used to calculate the dissolution factors, $f_{\rm Sn/Cu}$ and $f_{\rm Pb/Cu}$. The results of $f_{\rm Sn/Cu}<$1 and $f_{\rm Pb/Cu}>$1 indicate that the selective dissolution order and corrosion rates are Pb$>$Cu$>$Sn. The composition of corrosion products was analyzed and how the products are layered on bronze surface is explained. The corrosion products from inner to outer are CuCl, CuCl and Cu$_{2}$O, cupric compounds respectively.

Heparin homogeneously mixed with polyurethane in the co--solvent of tetrahydrofuran and water through adjusting the ratio of the two solvents. After the film was prepared with casting method, heparin was homogeneously blended in polyurethane films. At the same time, through preaction of heparin with 1--(3-dimethyl aminoprophyl)--3--ethylcarbodimide hydrochloride (DCCI), heparin partly grafted with the residual of polyurethane and the films containing free and covalent heparin was obtained using solvent casting. The heparin release rate was investigated with toluidine blue heparin assay (TBHA). The blood compatibility of polyurethane films was assessed with thrombin time (TT), prothrombin time (PT) and activated partial thromboplastin time (APTT). The results indicated that polyurethane containing heparin showed expected blood compatibility and polyurethane containing free and covalent heparin had the excellent bioactivity of free heparin and the long--term blood compatibility of covalent heparin.

The microemulsion solution is composed of isooctane as oil phase, sodium bis(2--ethylhexyl) sulfosuccinate (AOT) as surfactant, 1--octanol as cosurfactant, Ca(H$_{2}$PO$_{4}$)$_{2}\cdot$H$_{2}$O solution and Ca(OH)$_{2}$ saturated solution as water phase. Hydroxyapatite nanoparticles were successfully processed by mixing the both microemulsions. The partial ternary phase diagram of microemulsions was set by a series of demarcation points between optically transparent and opaque, which indicated the single phase area of the composition and the effect of reactant ions. The diameters of inverse micellars measured by dynamic light scattering (DLS) depended linearly on water content $w$ ($w$=[H$_{2}$O]/[AOT]) in case that micellars was near spherical morphology. The parameters of micellars were computed on the reactant concentration, AOT concentration and average diameter of micellars. Mechanism of reaction and particles growth showed that the reactant concentration and water content played an important role for the result particle size.

The influence of the behavior, mechanism, product structure and relation of structure with properties for co-curing reaction of epoxy resin and cyanate ester system catalyzed by transition metal acetylaceton, etc. was studied. The results show that the accelerator can obviously accelerate the co--curing reaction of the resin system and decrease the cured temperature and curing time. The reactions involved in the co--curing are: cyclodimerization and cyclotrimerization of cyanate, polyetherfication of epoxy group and cyclotrimerization of cyclic dimmer, as well as the formation of oxazolidone rings. In the lack of cyanate functional groups, the main structures of cured compounds are oxazolidone and polyether structure in the cured resin, and the triazine ring structure is of minor importance. In the excess of cyanate functional groups, the main structures are triazine ring and oxazolidone structure in the cured resin, and the polyether structure is of minor importance. The reactive activation energy and frequency factor of the co--curing resin system increase with enhanced concentration of cyanate. The thermal stability and dielectric properties of the cyanate and epoxy resin curing system are also found to increase with enhanced concentrations of cyanate in the same cured condition.

The morphology of low--profile unsaturated polyester resins cured at low--medium temperature was investigated. The experimental results show that the influence of temperature on morphology of cured sample is small for poly(vinyl acetate) based LPAs but large for polystyrene based LPA. Polar polymers tend to phase out from UPR and make system form co--continuous structure, which make for shrinkage compensation. Big difference of glass transition temperature $T_{\rm g}$ between UPR and LPA and a $T_{\rm g}$ below the cure temperature are preferred, which make microvoid formation of cured sample have more time and higher efficiency. For the sample with poly(vinyl acetate) based LPAs, the morphology exists two transitions with increasing the LPA concentration. LPA with higher molecular weights needs lower concentration to obtain co--continuous structure. However, for the sample with polystyrene based LPA, the morphology has little change with increasing the LPA concentration.

Nano--structure TiN thin films were deposited on silicon substrate at room temperature using filtered cathodic arc plasma (FCAP) system. The effects of negative substrate bias on the structure and property were studied. The microstructure and morphology of TiN thin films were characterized by AFM and XRD. The results show that the TiN thin films deposited by FCAP are very smooth and dense, and the grain size of the TiN ranges from 50$\sim$80 nm that increases with increasing the negative voltage. The preferred crystalline orientation was on the denser (111) orientation, and the friction coefficients of this kind of TiN films were lower than that of conventional TiN films. SEM photographs of wear trace indicated that the films were dense and macroparticle--free

Semi--solid A2017 alloys were compressed in semi--solid state by means of Gleeble--1500 thermal--mechanical simulator. The microstructures and relationship between the true stress and the true strain were analyzed. The deformation mechanism and forming property of A2017 semi--solid alloys were studied. The results showed that fine and homogeneous non--dendrite microstructures of semi--solid A2017 alloy manufactured by shearing--cooling--rolling (SCR) technology could be obtained and transformed into semi--solid structure which was composed of spherical grains and eutectic liquid through reheating process. The resistance to deformation in semi--solid state decreases as deformation temperature increases or deformation rate decreases. The deformation process of semi--solid A2017 alloy may be divided into four stages. At steady thixotropic deformation stage, the deformation mechanism is liquid flowing, solid particles rotating or sliding, and the thixotropic property is steady. The maximum deformation range is about 60\%.

Polycarbosilane(PCS--P) was synthesized by co--pyrolysis and polymerization using polydimethylsilane (PDMS) and polyvinylchloride (PVC), and SiC--C fiber was obtained by melt--spinning, curing and heat treatment process. The composition, structure and properties of precursors PCS--P and SiC--C fibers were investigated. The results showed that a small number of short carbon chains were introduced into structure of polycarbosilane when mixed ratios of PVC were in the range of 3\%$\sim$7\% by the polymerization. The SiC--C fibers prepared by such PCS--P have good crystallization and oxygenation resistance, and their resistivity decreases remarkably to 10$^{-1}\sim$10$^{1}\Omega\cdot$cm.

The friction properties of two kinds of self--asssembled monolayers with the same length of molecule chain and different functional groups were investigated. The effects of load and sliding velocity on the friction characteristics of SAMs were analyzed. The results indicate that the stronger the chemical activity of functional group in self--assembled molecules is, the more remarkable the SAMs cluster topography characteristics are. The friction forces increase with increasing the loads for these two self--assembled molecules with short chain. However, the effects of sliding velocity on the friction force appear when the chemical reactivity of functional group in self--assembled molecules is strong enough. The friction forces decrease markedly after the formation of SAMs with stable structure, which exhibits anti--friction effect. The anti--friction effect disappears if the load rises to a threshold for SAMs with stronger active functional group. The stronger the chemical activity of functional group in self-assembled molecule is, the larger the friction forces are.

A novel process for fabricating uncooled infrared detector array was introduced, instead of traditional technique used in the field of microelectromechanical systems (MEMS) in order to making self--support microbridge structures. The gridding method of ZnO layers prepared on Si substrate was developed. Both ZnO nanometer powders and PLZT thick films were prepared by improved sol--gel process. ZnO nanometer powders were characterized by TEM and PLZT thick films were analyzed by XRD. The ferroelectric and pyroelectric properties of PLZT--8/53/47 thick films were measured and studied. The results showed that grain size of ZnO nanometer powders ranged from 40 to 70 nm, and pure perovskite PLZT--8/53/47 was found and crystallization of PLZT--8/53/47 thick films was same as bottom electrode in direction. The thick film has high pyroelectric coefficient and low coercive field. The pyroelectric coefficient $p$ is 8.21$\times$10$^{-8}$C/(cm$^{2}\cdot$℃), and the coercive field +$E_{\rm c}$ is 32.0 kV/cm and 27.8 kV/cm, at 25℃ and 40℃ respectively.\par

A mixture of NiO, ZnO and $\alpha$--Fe$_{2}$O$_{3}$ powders was milled to synthesize the Ni--Zn ferrite by mechanochemical reaction. The formation process of the nanocrystalline was investigated by XRD, DSC and TG. After annealed at 600℃ in the air, the standard spinel structure was formed. The result showed that the values of as--milled nanocrystalline size changed from 15 nm to 32 nm. The best saturated magnetization intensity was measured, $\sigma_{\rm s}$ = 63.4 emu$\cdot$g$^{-1}$, indicating superior properties of soft magnetic materials. The atomic magnetic moments of the samples annealed at 800℃ under vacuum were calculated with a result from 3.4 to 3.7 $\mu_{\rm B}$.

Mechanical properties and microstructural characters of hot--rolled plates of an acicular ferrite steel for line pipe were investigated by transmission electron micrographs (TEM). The experimental results showed that hot--rolled plates of the acicular ferrite steel for line pipe possess excellent strength and toughness behaviors. Moreover, its microstructural characters possess several configurations under TEM, which are (1) ferrite laths with obvious interface, (2) ferrite laths without obvious interface, but the interface can be discerned faintly from the linear arrangment of those directional islands, (3) the coexistence of ferrite laths and non--equiaxed grains. These are somewhat different from those of weld structures, which are generally thought to consist of an assemblage of interwoven ferrite laths.

Effects of nickel content and mechanical alloying parameters on martensitic transformation during mechanical alloying of Fe--Ni as well as the mechanism were studied. There exists martensitic transformation during mechanical alloying of Fe--Ni, but whether reverse transformation takes place with further mechanical alloying depends on the nickel content. For nickel content less than 30\%(mass fraction), the highest temperature due to mechanical alloying is not high enough to reach the temperature at which strain--induced transformation of martensite to austenite starts, therefore martensite remains. However, further mechanical alloying of Fe--35Ni results in the transformation of martensite to austenite because strain-induced transformation temperature is lower. During mechanical alloying of Fe--35Ni, austenitic volume fraction increases with the increase of milling time, planetary rotation speed and the mass ratio of ball--to--powder because more energy can be provided for phase transformation.

Polycrystalline samples of La$_{0.67-x}$Ca$_{0.33}$MnO$_{3}$ ($x$=0.00, 0.02, 0.06, and 0.10) with different vacancies in La$^{3+}$--site were prepared by sol--gel method. The grain sizes of samples were observed by SEM. XRD results show that the samples are single phase of perovskite--type oxides. The Curie temperatures and the magnetic entropy change of the samples were studied by VSM. The influence of the vacancy concentration in La$^{3+}$--site on their magnetocaloric properties has been investigated. The higher Curie temperatures close to room temperature and the larger magnetic entropy changes have been observed. The maximum magnetic entropy change, 2.78 J/(kg$\cdot$K), is obtained near its Curie temperature (277 K) under the field of 1 T for La$_{0.67-x}$Ca$_{0.33}$MnO$_{3}$ ($x$=0.02) sample.