The microstructure and textural evolution of micro-carbon DP steel during the heating stage of continued annealing process was studied using SEM, XRD and EBSD technique. Results show that, the microstructure of hot-rolled plate consisted of ferrite and degraded pearlite. Deformed elongated ferrtite grains and deformed band was observed during cold rolling process. During the initial stage of recrystallization (from 720℃ to 750℃), the volume fraction of polygonal ferrite increased about 30%, and the deformed band easily induced the {001}~{112}<110> oriented grains nucleation and growth priority. During the latter stage of recrystallization (from 750℃to 780℃), ferrite was almost fully recrystallized, <111>//ND fiber grain grew up and gradually swallowed <110>//RD grain. The intensity of {001} <110> orientation significantly increased due to carbide dissolution during high-temperature annealing, and the <111>//ND fiber texture hardly affected by transformation.

At different rolling temperatures of 850, 900 and 950℃ with constant vacuum level of 1×10^-2 Pa and total rolling reduction ratio of 90%, the three-layer clad plates of pure Ti/high strength low alloy (HSLA) steel/pure Ti were successfully fabricated via vacuum rolling cladding (VRC) without the addition of interlayer, and the influence of interfacial microstructures on the bonding properties of the clad interface was investigated in detail. At a rolling temperature of 850℃, the clad interface only contained continuous TiC layer 0.5 μm in thickness, while at rolling temperatures of 900 and 950℃, the interface consisted of TiC and β-Ti. With increasing the rolling temperature, the interfacial thickness gradually increased. Under various rolling temperatures, an obvious ferrite band was detected in the HSLA steel side adjacent to the clad interface, and this width significantly increased as the rolling temperature increased. At a rolling temperature of 900℃, a maximum interfacial shear strength of 337 MPa with the fracture occurring at the interface between HSLA steel and TiC was achieved, and after 180° bending testing, no macro/micro-crack was generated at the clad interface, showing sound bonding properties of the clad plate through VRC.

3-(N, N-dimethylhexadecylammonio) propane sulfonate (HDAPS) was used as modifier for the preparation of organo-betonite, the resulted HDAPS-Bt was characterized by XRD, FT-IR, SEM and BET. The results show that the amphoteric surfactant successfully intercalated into the interlayer of bentonite, and expanded the basal spacing to high extent, the morphology of bentonite was improved and the specific surface area were decreased, while the pore size was enlarged. The adsorption of ciprofloxacin onto HDAPS-Bt modified with different amount of HDAPS was tested, results show that the optimum adsorption ratio was obtained at 0.2 CEC both in acidic and basic solutions. The pH and ionic strength in the solution had great effect on the adsorption of CIP onto raw bentonite, and adsorption capacity decreased dramatically with increasing of pH and ionic strength. However, the organo-bentonite was much easier to disperse in the solution and separate from water than raw bentonite, the adsorption of CIP on HDAPS-Bt was 30% higher than that on Bt, furthermore, pH and ionic strength had less effect on the adsorption of CIP onto HDAPS-Bt in comparison with raw bentonite. The adsorption experiment results show that pseudo-second-order was best for the description of kinetics and the adsorption isotherm was nearly linear.

ASTRACT Pt/BiOCl nanostructures were prepared by a facile low-temperature solvothermal-impregnation method and were characterized by XRD, EDS, SEM, (HR)TEM, N₂ Adsorption-desorption, UV-Vis Absorption Spectroscopy and fluorescent probe method. The photocatalytic performance was evaluated by photodegrading gas-phase toluene under Xe light irradiation. The results show that Pt/BiOCl nanostructures have good crystallinity and exhibit a BET specific surface area of 28.48 m²/g. The samples display excellent optical absorption properties in the range of both UV light and visible light. The ability of forming hydroxyl radicals on the surface of photocatalysts was also enhanced a lot. The photocatalytic performance was improved obviously. Under Xe light irradiation, the photocatalytic efficiency increased by 70% compared with the sample of BiOCl nanostructures without being modified with Pt nanoparticles. And that value increased by 6.6 times when being compared with that of BiOCl nanosheets. Additionally, the modification of Pt nanoparticles on the surface of BiOCl nanostructures also played a part in inhibiting the formation of formaldehyde and thus preventing more hazardous secondary pollution during the photocatalysis of toluene. The improved photocatalytic activity of Pt/BiOCl nanostructures associates with their efficient separation of photogenerated carriers.

The layered double hydroxides containing rare earth element (MgAlZnLa-CO₃ LDHs) with different proportions of metal ions were prepared successfully by the constant pH coprecipitation method. Ammonium polyphosphate, Melamine, and MgAlZnLa-CO₃ LDHs were added in poly (butylene succinate) via melt blending to obtain the novel intumescent flame retardant poly (butylene succinate) (IFR-PBS) composites. The study on the effect of MgAlZnLa-CO₃ LDHs on thermal and flame retardant properties of IFR-PBS composites was investigated. It was revealed that IFR-PBS composites can achieve the goal of vertical flammability (UL94) V-0 rate and the limiting oxygen index (LOI) value of 33% when the content of MgAlZnLa-CO₃ LDHs was 1% (the total loading of flame retardant was 20%). The LOI of IFR-PBS composites depended not only on the amount of the char, but also on the structure of the char layer. The addition of MgAlZnLa-CO₃ LDHs could promote the formation of graphite structures on the outer surface of the char layer to improve its strength and compactness markedly. Cone calorimeter test results also showed that the carbon layer of high density due to combustion can effectively reduce the release of flammable small molecules and soot as a result of the decrease of the heat release rate and smoke production rate.

A comparative study of performance advantages was made between Ti/Al composite electrode and conventional Ti electrode. Ti/Al composite electrode was fabricated by hot-pressing diffusion compound method. And the microstructure and properties of the novel electrode substrate materials were investigated by SEM, EDS, four-probe method and electrochemical measurements. The results show that the single phase of TiAl₃ formed in Ti/Al compound interface has stable structure and excellent electrical conductivity under the condition of 540℃ sintering temperature and 90min holding time. In this case, the composite electrode has the lowest interfacial resistance and the best electrochemical performance. In this paper first principles calculations were applied to study the formation enthalpy and binding energy of four kinds of Ti/Al intermetallic compounds. The order of formation enthalpy is as following: Ti₃Al< TiAl< TiAl₂< TiAl₃; the order of binding energies is as following: Ti₃Al< TiAl< TiAl₂< TiAl₃. The formation mechanism of single interface diffusion layer of TiAl₃ was explained from the view of thermodynamics. And growth dynamics equation of interface diffusion layer is obtained by diffusion kinetics calculation.

The influence of electric pulse frequency on the solidification microstructure and mechanical properties of high-boron middle-carbon alloy has been investigated. The experimental results show that electric pulse has obvious influence on the eutectic ledeburite and hard phase of the steel, lead to the change of mechanical properties. The ledeburite in the steel disappeared and the continuious boron carbide hard phase was broken into small particle, which lead to the improve of hardness and impact toughness of high-boron middle-carbon alloy. Along with the frequency increasing, the influence on the solidification microstructure and properties of the steel is more obvious. The influence is the results of the joule heating, the electromigration effect and electric magnetic effect.

The microstructure of annealing He-Ti films and evolution of corresponding helium-related defects were studied by X-ray diffraction (XRD) and slow positron beam analysis (SPBA) respectively. Results of XRD indicate that Ti reacts with Si to form the stable polycrystalline TiSi₂ compound after high temperature annealing. The preferred orientation of TiSi₂ could be mainly affected by the incorporation of helium atoms, while helium atoms introduced weakly influence on the grain sizes of TiSi₂ compound. The results of SPBA demonstrate that helium-related defects increase with the increasing of the He concentration at room temperature. Furthermore, when He concentration is below 5%, except for 2% sample the concentrations of He-related defects raise correspondingly as the helium concentration grows after annealing. However, when the He concentration reaches up to 14%, high-concentration helium atoms, helium-filled vacancy clusters and small size of He bubbles tend to migrate and coalesce to form larger He bubbles under high temperature annealing conditions, thus small helium-related defects which are close to surrounding of larger bubbles will accordingly reduce.

A kind of high volume fly ash concrete was prepared by using fly ash, barren rocks and iron tailings as the main materials. This high-strength concrete which was made by using barren rocks and iron tailings as aggregates contained ninety percent industrial solid wastes, its compressive strength under standard curving conditions was up to 83.27 MPa at the 28 days curving ages. Effects of fly ash on the working performance, mechanical performance and hydration process of the cementitious materials were investigated. The hydration properties and microstructure characteristics were analyzed by the XRD, TG-DSC and SEM. The results show that the fly ash can reduce the water consumption, slow down the hydration process and improve the mechanical properties of the cementitious materials. And the fly ash can consume the calcium hydroxide which was produced during the early hydration process, motivate the secondary hydration process, so as to ensure steady increase of the long-term strength.

Carbide (Cr, Fe)₇C₃-reinforced Fe-based composite coating was fabricated by plasma transferred arc (PTA) cladding with Fe-CrNiBSi and Cr₃C₂ powder blends. The nucleation and growth of (Cr, Fe)₇C₃ were observed and analyzed by OM, SEM, EDS, XRD, simultaneous DSC-TGA, and thermodynamic analysis (TA). And the friction and wear performances of (Cr, Fe)₇C₃-reinforced Fe-based composite coating were measured by using M-2000 tester. The SEM results show that plenty of (Cr, Fe)₇C₃ with long hexagonal shape in-situ grow on the survived Cr₃C₂ particle. The TA results show that Cr₃C₂ can effectively act as the substrate for the nucleation of (Cr, Fe)₇C₃ rod, thus can promote the formation of (Cr, Fe)₇C₃ rod in the composite coating. Further, there are some holes inside the rod, and some cracks outside the rod. These cracks always formed near the intersections between rods. During the variable loads dry sliding friction and wear process, the wear resistance of (Cr, Fe)₇C₃-reinforced coating is higher than that of the pure Fe-CrNiBSi alloy coating. But there are a lot of vertical cracks on the worn surface of (Cr, Fe)₇C₃ rod along the sliding direction due to the high brittleness and low fracture toughness of the rod.

The relationships of multidimensional seepage about continuous phase, dispersion strengthening phase and decentralized deterioration phase of the phosphogypsum-based material’s space were described. The porosity, pore size distribution (PSD), characteristic pore size and specific surface area (SSA) of the samples were measured by mercury intrusion porosimetery (MIP). The effect of these parameters above mentioned on the compressive strength of system I and system II was investigated. The results show that a lower hydration extent by the limited water supply and high capillary tension contributed to form the pore path precolation and low compressive strength. There are two PSD peaks in the pore size ranges of 3-200 nm and 200 nm-8 μm for all the samples. The pore-percolation changed by dosage of raw materials and specific strength reduce with increasing the water-cement ratio and the relationship among specific strength, shape factors and volume fraction follow roughly the power law, that is . This model, , exhibited certain superiorities in fitting the correlation and compensated for the perdiction about value and the actual value for different pore structure of several existing models.

Alloy powders were deposited on the surface of ASTM G3101 by the method of welding wire-alloy power block hardfacing. The microstructures and wear resistance of hardfacing layer was characterized by x-ray diffraction(XRD), scanning electron microscope(SEM), energy dispersive X-ray analysis(EDS), Macroscopic hardness meter, and spectrometer. Effect of titanium on microstructure and wear resistance of high-chromium hardfacing alloys was investigated. The results show that the high quality metallurgical bonding of substrate and deposited layer was obtained by metallurgical reaction during gas metal arc welding (GMAW) process, and the microstructure of welding wire-alloy power block hardfacing layers mainly consist of (Cr, Fe)₇C₃, TiC carbides, Ti_x(C, N)_y carbonitrides and α-Fe (C_0.14Fe_1.86 and C_0.12Fe_1.88 martensite)(BCT) besides little amount of retained CFe_15.1 austenite (Fe-C)(FCC) matrix. The hardness increases rapidly with titanium content increasing, hardfacing layer hardness value reached 60 when it is less than 3% (mass%, similarly hereafter), on the contrary, wear loss of the hardfacing layers decrease with increasing of titanium in the hardfacing layer.

A facile solution method to develop cuprous oxide (Cu₂O) film on the copper substrate is reported, and then the superhydrophobic cuprous oxide surface was obtained by modifying Cu₂O film with 1-Dodecanethiol (TDDM), which with a water contact angle (WCA) of about 157.7°, as well as a small sliding angle (WSA) less than 2°. The as-prepared sample was characterized by X-ray diraction (XRD), ?eld emission scanning electron microscopy (FESEM), contact angle measurements and electrochemical work station. The results show that the superhydrophobic Cu₂O surface has the excellent non-sticking property and possessed better corrosion resistance as compared with the bare copper.

The L929 cells of mouse were treated in vitro with leaching liquids of 3 dental alloys (a gold alloy, a cobalt-chromium alloy and a nickel-chromium alloy) .The effects of the leaching liquids on proliferation and apoptosis of L929 cells were examined by flow cytometry to evaluate the biocompatibilities of 3 dental alloys. Results show that the gold alloy has little effect on the proliferation and apoptosis of the cells, with less cytotoxicity, demonstrated its biocompatibility is excellent; the nickel-chromium alloy has greater impact on the proliferation and is likely to induce apoptosis, with great cytotoxicity and poor biocompatibility; and the performance of the cobalt-chromium alloy is in the middle of above two alloys, and its biocompatibility is good as well.

The strain induced precipitation properties of titanium was investigated by stress relaxation method at 600 - 1100 ℃ temperature, 30% -50% deformation in high Ti contained steels with Ti addition level of 0.15% mass percent. The results show that Ti has a distinct strain-induced precipitation process at 600 - 1100 ℃ temperature range, this process is not only present in the single-phase austenite region, but also in ferrite-austenite two-phase and ferrite single-phase region. The precipitates were downsizing with the decreasing of the temperature. Above 1000℃ size of the precipitates is bigger, but below 900 ℃ precipitates with the size of a few to tens of nanometers appeared. When the temperature decreased to below 700℃, the size of precipitates downsized to 3 nm around. In the temperature range of 800 - 1100℃, the start time of the precipitation were all about 2 seconds, but just began to precipitate a small amount of precipitates at only a few parts at the beginning. Precipitation is a continuous process, and it needed different times in different parts of the sample. 10 seconds later, there would be a homogeneous precipitation process of large number of TiC, and it was ended at 300-700 seconds. The precipitation time - temperature (PTT) curve do not abide by the typical "C" curve feature. Among three deformations, 40% and 30% had similar deformation resistance, the recovery rate and the start time of precipitation, but TiC precipitated faster for 40% deformation than that of 30%. After relaxation, the residual stress was the greatest, and precipitation hardening would be the most obvious for 40%’s deformation. Increasing deformation to 50%, deformation resistance increased distinctly, and recovery became faster while the start time of precipitation delayed from 2 seconds to 2.7 seconds. After relaxation, the residual stress was the lowest for 50% deformation.

A physical model has been established to predict the stress-strain relations during the deformation of the two-phase materials, in which the effect of grain size and volume fraction of the phases on the change in strain and stress are completely considered. The predictions are good agreement with the experimental results. The micro-stress-strain partitioning between martensite (hard phase) and ferrite (soft phase) was quantitatively analyzed in the martensite-ferrite dual-phase steel. It is shown that the grain size and volume fraction greatly influence the stress-strain partitioning of the constituent phases. The stress ratio of the hard to soft phase decreases with the increase of the hard phase volume fraction. The strain ratio of the soft to hard phase increases before the plastic deformation of the hard phase starts when the relative macro-strains is applied. However with the macroscopic strain increasing, the hard phase begins to plastically deform and the strain ratio gradually reduces and eventually approaches to a constant. And the steel with relatively higher volume fraction of the hard phase has the relatively smaller constant value. In the case of a definite volume fraction, increasing the relative grain size of the hard phase contributes to the increase of the overall plasticity of the steel, while reducing the relative grain size of the hard phase helps to improve the overall strength of the steel. The optimal performance of the steel is achieved only when the grain size ratio of hard to soft phase is controlled within an appropriate range where each of constituent phases plays its most potential value.