Uniform ZnO toothed-nanobelts and nanocombs were fabricated respectively through pure zinc powder evaporation without catalyst at temperature of 600–650 °C. Scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM) observations show that such ZnO nanostructures have several types in morphology, and all of them are single crystalline. The experimental results reveal that the growth of the ZnO nanostructures was controlled by vapor-solid mechanism. Room temperature photoluminescence spectra of the toothed-nanobelts show a UV emission at ∼ 390 nm and a broad green emission with 4 subordinate peaks at 455–495 nm.

In order to improve the mechanical properties of PVC, by solid-phase grafting reaction, grafting on and nano-modifying the PVC process synchronously, acrylic monomers not only graft on PVC, but also are intercalated into the layers of MMT in the heating process. Blending PVC and the MMT-PVC grafting copolymers, we can get nanocomposites of PVC/grafters/MMT, and the mechanical performance of the material is improved.

The preparation and electrocatalytic activity of polyaniline-poly(propylene oxide) (PAN-PPO) modified by Pt particles (Pt/PAN-PPO) were investigated. Pt/PAN-PPO was characterized by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Pt particles on PAN-PPO were in the nanometer range, and dispersed in a three-dimensional distribution on the surface of PAN-PPO film. Compared with polyaniline and glassy carbon modified with Pt particles under the same conditions, Pt/PAN-PPO exhibited a high electrocatalytic activity for lysine oxidation.

Titanium dioxide/kaolinite nanocomposite was prepared by the sol-gel method, with layered kaolinite as a substrate and Ti(OC₄H₉)₄ as a precursor. The effects of hydrolysis, drying and calcination on the production of nanometric titanium dioxide were discussed. The optimal conditions for preparation were obtained through experiments. The 1–10 nm thick monolayer anatase nano TiO₂ crystal was produced under the conditions as follows: hydrolyzed at 37–42 °C for 4 h, dried at 70–80 °C for 1 h, and calcined at 550–650 °C for 3 h. The rate of degradation of 40 mg/L azo dye and 20 mg/L acid red dye can reach 96% and 81.45%, respectively.

In order to increase the yield of hydrogen production for hydrogen-producing microbe, the enhancement effect of nanometer-sized gold particles on the activity of hydrogen-producing microbe was studied. The yields of hydrogen production in the system added by gold nanoparticles of 6 nm and 12 nm in diameter were obviously increased by about 17% and 9% in contrast to that in blank system. The experimental results indicate that gold nanoparticles could significantly enhance the bioactivity of hydrogen-producing microbe.

(CdS/TiO₂)/MCM-41 loaded nanometer photocatalyst was prepared by the sol-gel method and dipping process, the photocatalytic degradation of methyl thionine chloride in water was investigated by using the photocatalyst. The experimental results show that the optimum concentration of CdS over TiO₂ was 3% (molar ratio), the photocatalytic activity was enhanced when making TiO₂ the anatase phase with a rise of the roasting temperature, and the carrier, mesoporous molecular sieve MCM-41, was beneficial to improving the photocatalytic activity of TiO₂ for photocatalytic degradation of methyl thionine chloride. The morphology and the crystalline phase of the photocatalyst were discussed by means of XRD and SEM techniques, and the reaction mechanism of catalytic properties was also discussed.

Stable clay/waterborne polyurethane nanocompostie dispersions were synthesized by sulfonated poly (butylene adipate) diol, 4,4-diphenylmethane diisocyanate, dimethyl propionic acid, 1,4-butanediol, triethyl amine and clay-water dispersion through a route named prepolymer acetone mixing progress. The reinforced mechanical properties and thermal resistance of films casting from it were examined by dynamic mechanical analyses (DMA), thermogravimetric analyses (TGA) and tensile tests. Furthermore, the morphology of these nanocompostie films and dispersions were observed by transmission electron microscopy (TEM), scanning electron microscopy (SEM), wide-angle X-ray diffraction analyses (WXRD). The experimental results reveal that the clay could be predominantly dispersed in the pristine polymer forming nanocomposties, and evidently enhanced the tensile properties and modulus of it. Additionally, the best-reinforced effect could occur when the clay content was near 1 wt%.

A new method of preparing nanoparticles by pulsed-laser ablation of a tiny wire was reported, and pure maghemite (γ-Fe₂O₃) nanoparticles were synthesized by this method in a mixed gas flux of N₂ and O₂ at atmospheric pressure. The obtained γ-Fe₂O₃ nanopartiles were in the runge of 5 to 80 nm in diameter and largely spherical in shape. Structural characteristics and morphologies of the nanoparticles were characterized by XRD and TEM, respectively. Moreover, magnetic properties of the obtained γ-Fe₂O₃ nanopartiles in the temperature range of 300 to 773 K were investigated. The experimental results demonstrate that the squareness value of the hysteresis loop decreases with increasing temperature. Both the coercivity and the saturation magnetization of the γ-Fe₂O₃ nanoparticles show a constantly decreasing trend with increasing temperature up to the occurrence of the transformation from γ-Fe₂O₃ to α-Fe₂O₃. Especially, at the temperature of 773 K, the γ-Fe₂O₃ begins to transform to the α-Fe₂O₃ phase and the hysteresis loop becomes unclosed.

Nanostructured (NS) W−Cu composite powder was prepared by mechanical alloying (MA), and nanostructured bulk of W−Cu contact material was fabricated by hot press sintering in an electrical vacuum furnace. The microstructure, electric conductivity, hardness and break down voltage of NS W−Cu alloys were measured and compared to those of conventional W−Cu alloys prepared by powder metallurgy. The experimental results show that microstructural refinement and uniformity can improve the breakdown behavior and the electric arc stability of nanostructured W−Cu contacts materials. Also, the nanostructured W−Cu contact material shows the characteristic of spreading electric arcs, which is of benefit to electric arc erosion.

To protect the surface of NiTi from corrosion, an ion implantation method was proposed. In the present work, a surface oxidized sample was implanted with nitrogen at energy of 100 keV. The corrosion resistance property was examined by the anodic polarization method in a simulated body fluid (SBF) at a temperature of 37°C and contrasted to non-implanted NiTi samples. The composition and structure of the implanted layers were investigated by XPS. The experimental results from the electrochemical measurements provide an evidence that the nitrogen ion-implantation increases the corrosion resistance of NiTi shape memory alloy.

Varieties of zinc and Zn−Co alloy compositionally modulated multilayer (CMM) coatings were electrodeposited onto steel substrates using dual bath technique. The surface and cross-sectional morphologies of coated samples were examined using scanning electron microscopy (SEM). The existence of internal stress in Zn−Co alloy deposits was confirmed by the cross-sectional morphologies for the occurrence of micro-cracks in the thick Zn−Co alloy deposit alone. The corrosion performance was evaluated using neutral salt spray testing, corrosion potential measurement and anodic polarization methods. The experimental results show that the zinc and Zn−Co alloy CMM coatings were more corrosion-resistant than the monolithic coatings of zinc or Zn−Co alloy alone with a similar thickness. The analysis on the micrographic features of zinc and Zn−Co alloy CMM coating, using field emission gun scanning electron microscopy (FEGSEM) after corrosion testing, explains the probable reasons why the Zn−Co/Zn CMM coating system has a better protective performance.

The effect of calcium addition on the microstructures of AZ91 magnesium alloy was investigated. It was found that a small amount of calcium in AZ91 alloy produced a large decrease in the α-Mg grain size and the dispersed fine β-Mg₁₇Al₁₂ phases. In addition, some Al₄ Ca particles were found to exist in the AZ91 alloy containing 0.5wt% Ca. EDS analysis and water-quenched technique revealed that the grain-refining mechanism of calcium for the AZ91 alloys was mainly attributed to the role of restricting growth of calcium in the primary α−Mg crystals.

A new kind of anti-oxidation inorganic nano-coating for the common low carbon steel was prepared. It included magnesite mineral, metallurgic dust and silicate adhesive as the main raw materials. The nano-coating could be sprayed directly onto the low carbon steel slab even though with hot surface as far as under 1000°C. And at the same time, a compact thin nano-film was formed, and the film would inhibit the oxygen into the interface of the steel body and decrease the loss of weight because of oxidation. The loss was decreased by about 60% or more. The properties and mechanism of oxidation resistance of the coating were discussed through XRD, TG-DTA and SEM. The experimental results show that many reactions woulld happen among the components of the coating and then many microspheres with the size of 80–100 nm generated in the system. By using the heat of the steel body, the silicate adhesive would interact with the microspheres, and the other components of the coating would be soft and sintered so that when the coating was sprayed onto the surface of the steel slab, the intact and compact film could be formed and adhesive with the steel body. Besides the special properties of anti-oxidation, the coating could prevent the volatilization of microelement in the steel such as silicate and carbon at a high temperature. So it can improve the quality and output of steel with this new kind of nano-coating.

The effects of stretching ratio and stetching temperature on phase transition of melt-spun poly (vinylidene fluoride) fibers were investigated and analyzed by using scanning electron microscopy, wide angle X-ray diffraction, differential scanning calorimetry and Fourier transfer infrared spectroscopy. The β phase exists in the as-spun fiber. The β phase content increases as the stretching ratio increases. When the stretching temperature is lower than 100°C, enhancing temperature is good for the transition of phase α to β. By contrast, when the stretching temperature is higher than 100°C, enhancing temperature is unfavourable for the transition of phase α to β. Increasing the draw temperature increases the α-phase content

To improve the performance, the surface of LiMn₂O₄ was coated with very fine MgO, Al₂O₃ and ZnO by sol-gel method, respectively. The structure and morphology of the coated materials were investigated by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). The charge and discharge performance of uncoated and surface modified LiMn₂O₄ spinel at 25°C and 55°C were tested, using a voltage window of 3.0–4.35 V and a current density of 0.1 C rate. There is a slight decrease in the initial discharge capacity relative to that of uncoated LiMn₂O₄, but the cycle ability of Li LiMn₂O₄ coated by metal-oxide has remarkably been improved. The EIS measurements of uncoated and Al₂O₃-coated LiMn₂O₄ were carried out by a model 273 A potentiostat/galvanistat controlled by a computer using M270 software, and using a frequency response analyzer (Zsimpwin) combined with a potentiostate (PAR 273). Consequently, the reason for the improved cycle properties is that the surface modification reduces the dissolution of Mn, which results from the suppression of the electrolyte decomposition, and suppresses the formation of passivation film that acts as an electronic insulating layer. In conclusion, the use of surface modification is an effective way to improve the electrochemical performance of LiMn₂O₄ cathode material for lithium batteries.

A chemical deposition was supposed to be an efficient method in preparation of nano-sized Sn/MWNTs. The nanocomposites of MWNTs and Sn/MWNTs were both used as anodes of lithium ion battery. The special capacities and coulomb efficiencies of Sn/MWNTs were studied by means of electrochemical methods. The coating of Sn on MWNTs observed by TEM was amorphous and nano-sized. The reversible capacity of Sn/MWNTs, which was much larger than that of MWNTs, was 824 mAh/g in the 1 st charge and discharge cycle. The coulomb efficiency of Sn/MWNTs in the 1 st cycle was increased by 16% compared with that of MWNTs. The additional Sn, which was 37 wt% of total Sn/MWNTs' weight, introduced the additional reversible lithiation capacity at least 250 mAh/g in the 40 charge and discharge cycles. The dispersing degree of Sn on MWNTs was the main reason for the influence of the electrochemical performance of the Sn/MWNTs. Sn/MWNTs is proved to be a promising candidate as an anode of lithium ion battery.

Yttrium-filled skutterudites Y_yFe_xCo_4−xSb₁₂ (y=0–0.40) were synthesized. The effect of Y filling fraction on thermoelectric properties of Y_yFe_xCo_4−xSb₁₂ was investigated. All samples showed p-type conduct. The electrical conductivity decreased with increasing filling fraction y. The Seebeck coefficient increased with increasing temperature. The lattice thermal conductivity decreased with increasing filling fraction y and showed the minimum value at a certain filling fraction y=0.3. The effect of different filling atoms M (M: Ba, Ce, Y) on the lattice thermal conductivity of M_yFe_xCo_4−xSb₁₂ was discussed. The maximum ZT value of 0.7 was obtained for Y_0.08Fe_0.7Co_3.3Sb₁₂ at 750 K.

Zn²⁺-or Ti⁴⁺-substituted cordierites with the nominal compositions of Mg_1,6Zn_0.4Al₄Si₅O₁₈ and Mg_1.8Ti_0.2Al_4.4Si_4.6O₁₈ respectively, were prepared by a conventional solid state reaction method. The structure of the substituted cordierites was characterized by X-ray diffraction (XRD), infrared (IR) spectroscopy and²⁹Si magic angle spinning (MAS) nuclear magnetic resonance (NMR). The infrared radiation properties were investigated in the bands within 2. 5–25 μm. Compared with the un-substituted cordierite composition (Mg₂Al₄Si₅O₁₈), Zn²⁺-or Ti⁴⁺-substituted cordierites show superior infrared properties. XRD and IR results confirm the formation of hexagonal α-cordierite as the main crystal phase for the substituted cordierites.²⁹Si MAS NMR result indicates that Zn²⁺ or Ti⁴⁺ substitutions for partial Mg²⁺ of α-cordierite promoted the ordering of the distribution of Al and Si atoms in T₁ (tetrahedra connecting six-membered rings together with [MgO₆] octahedra) and T₂ (tetraheda forming six-membered rings) tetrahedral sites. This resulted in a lattice deformation and increased the anharmonicity of polarization vibration, which is responsible for the improvement of infrared radiation properties of the substituted cordierites.

The N-doped TiO₂ polycrystalline powder was synthesized through calcining the hydrolysis product of tetra-butyl titanate with ammonia. The photocatalytic activity of N-doped TiO₂ powder with anatase phase calcined at 400 °C was 2.7 times higher than that of Degussa P25 for phenol decomposition under visible light. All samples had mesoporous structures. X-ray photoelectron spectroscopy confirmed that a trace amount of N atoms remained in the anatase polycrystalline TiO₂ powder when calcined at 400 °C as substitutional atoms at the oxygen sites. UV-Vis and EPR analyses indicated that oxygen vacancy states were created during the course of N-doped TiO₂ powder formation. It is considered that substitutional N atoms, oxygen vacancy states, large BET surface areas and mesoporous structure are important factors for the N-doped photocatalyst to present a high vis-activity.

The effects of types and amounts of silane coupling agent on mechanical properties of vulcanized rubber microwave absorbing patch (VRMAP) were studied. The mechanisms of silane coupling agent's effects on mechanical properties of rubber microwave absorbing patch (RMAP) and microwave absorbing patch's (MAP's) microstructure were also discussed by using SEM and FT-IR. The experimental results show that the tensile strength of RMAP could be increased through adding the filler of carbonyl iron powder (CIP) modified by silane coupling agent. RAMP filled with CIP, which was treated by silane coupling agent KH550, possessed a high tensile strength of 11.5 MPa, which was 448% more than that of MAP whose filler was not modified by any coupling agent. It was found that the optimal amount of KH550 was 1.0 phr to 100.0 phr carbonyl iron powder. The effects of different modifying techniques on RMAP's mechanical properties were also investigated. It is indicated that MAP whose filler is modified by the wet process has the highest tensile strength, but it is not the optimal modifying technique due to complicated wet process. On the contrary, the dry process was very simple, and VRMAP possessed fairly high mechanical properties, therefore, it was the perfect modifying process.

High pressure method was used for the first time to produce rectorite clay (REC)/phenolic resin (PF) and organic rectorite clay (OREC)/phenolic resin and montmorillonite (MMT)/phenolic resin (PF) nanocomposites. The structure of the material phase was studied by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA), and atomic force microscopy (AFM). The experimental results show that intercalated clay/resin nanocomposites could form under normal temperature and high pressure conditions by the intercalation of polymeric molecules rather than interlayer polymerization.

A superabsorbent polymer was prepared by grafting sodium acrylate (SA) onto Konjac flour using potassium persulfate (KPS) and N, N′-methylene bis acrylamide (MBA) as an initiator and crosslinker, respectively. The effect of various preparation conditions on its water absorbency was investigated. When the Konjac Flour content was 3.0 g, the acrylic acid (AA) content was 30.0 g, the amount of initiator was 0.150 g, the neutralization degree of monomer was 85%, the reaction temperature was 60°C and the amount of crosslinker was 0.025 g, the polymer's absorbency was 750 times in pure water and 279 times in tap water at ambient temperature. It had also high water retention. The graft efficiency reached 67%. The analyses of FT-IR and SEM indicate that sodium acrylate is grafted on the polysaccharides of Konjac flour.

A series of elastomers, based on NBR, polysiloxanes (PS) were prepared and characterized by tensile tests, thermogravimetry (TG) and differential scanning calorimetry (DSC). Two kinds of vulcanizing agent, DMDBH (2,5-dimethyl-2,5-di(t-butyl perory) hexane) and DCP (dicumylperoxide) were used to investigate the influence of different vulcanizing agents on properties of PSINBR. The addition of PS to NBR was found to improve the thermal stability and decrease the tensile strength of NBR. The tensile strength decreased considerably while the elongation at break increased obviously with the increase of PS content. The series using DMD-BH as vulcanizing agent showed a higher tensile strength and elongation at break than the series using DCP as vulcanizing agent. Simultaneity the thermal stability increased with the increase of PS content.

The difference of sensitivity to indole-3-acetic acid (IAA) combined with horseradish peroxidase (HRP) in K562 and BXPC-3 cells was investigated. The cell proliferation was determined by MTT assay. The cell cycle and apoptosis of K562 and BXPC-3 cells were examined by a fluorescence flow cytometer (FCM) and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) respectively. The experimental results show that IAA and HRP could inhibit BXPC-3 cell proliferation greatly compared with K562 cell during the first 48 h. The cell cycle was arrested predominantly at G2/M phase in K562 and BXPC-3 cells. The cell apoptosis of K562 and BXPC-3 was induced by IAA/HRP. There was a significant difference between the two cell lines since BXPC-3 cells were more sensitive than K562 cells by treatments with combination of IAA and HRP.

The contraceptive efficacy and local effects of bioceramic IUD in rat were studied. The experiment was divided into four groups: bioceramic IUD group; stainless steel IUD group; operation control group; normal control group. All IUD samples were put into uterus of rats. The experimental results show that the alumina bioceramic has a strong contraceptive effect for those rats. In bioceramic IUD group the endometrial inflammation reaction was as mild as that in stainless IUD group during the early days (30 days) and gradually abated with time during the late days (60 days). The experiments show that the alumina bioceramic has a good biocompatibility and contraceptive effects and hint at the alumina bioceramic IUD may become a more safety reproduction family planning IUD.

The inhibition effect of hydroxyapatite (HAP) nanoparticles on hepatocarcinoma was investigated in vivo. The human hepatocarcinoma cell line Bel-7402 was transplanted subcutaneously into nude mice. Hydroxyapatite nanoparticles suspension at a dose of 0.2 mL was injected into the transplanted tumors every day for 2 weeks, and saline was used as control. The efficacy of hydroxyapatite nanoparticles on this carcinoma was surveyed and morphological changes of tissue and cells were observed by light microscopy and transmission electron microscopy (TEM). Experimental results show that hydroxyapatite nanoparticles have a visible destructive effect on the structures of hepatocarcinoma cells and tissue. The inhibition rates of tumor growth were 77.21% and 51.32% after intra-tumor injection of hydroxyapatite nanoparticles for 1 week and 2 weeks, respectively. Compared with the control group, hydroxyapatite nanoparticles can also prolong the survival time of the nude mice bearing this cancer significantly. This indicates that hydroxyapatite nanoparticles have the therapeutic potential on hepatoma in vivo.

A method of QWI (quantum well intermixing) realizing through plasma-enhanced chemical vapordeposition (PECVD) SiO₂ film following ion implantation was investigated. PECVD 200 nm SiO₂ film after 160 keV phosphorus (P) ion implantation was performed to induce InP-based multiple-quantum-well (MQW) laser structural intermixing, annealing process was carried out at 780°C for 30 seconds under N₂ flue, the blue shift of photoluminescence (PL) peak related to implanted dose: 1×10¹¹ 1×10¹², 1×10¹³, 3×10¹³, 7×10¹³ ion/cm² is 22 nm, 65 nm, 104 nm, 109 nm, 101 nm, respectively. Under the same conditions, by comparing the blue shift of PL peak with P ion implantation only, slight differentiation between the two methods was observed, and results reveal that the defects in the implanting layers generated by ion implantation are much more than those in SiO₂ film. So, the blue shift results mainly from ion implantation. However, SiO₂ film also may promote the quantum well intermixing.

The correlation between outdoor exposure and indoor accelerated corrosion test for high polymer materials was investigated according to the variation of the functional group of exposure models aged. Environment aging intesities at different zones (Wuhan and Lasa with the same latitude) and the influences of indoor accelerating factors including water and ultraviolet on weathering performance of high polymer materials were also studied by comparing different indoor accelerated corrosion testing results. The experimental results show that: by testing variations of carbonyl exponent of polythene (which represented the degradation behavior of high polymer materials due to ultraviolet oxidation of double bond) and ultraviolet absorbance of polycarbonate (which represented the degradation behavior of high polymer materials due to abevacuation of branched chain), the degradation behavior of high polymer materials could be studied. Carbonyl exponent of polythene exposed in Wuhan and Lasa for 1 year was equal to that exposed in indoor cycle ultraviolet for 128 h and 170 h, respectively, the ultraviolet absorbance of polycarbonate exposed in Wuhan for 1 year was equal to that exposed in indoor cycle ultraviolet for 240 h. The ratio of environment aging intensity of Lasa to Wuhan was around 1.2. With the prolongation of cycle accelerated ultraviolet exposure time, the variations of carbonyl exponent of polythene and the ultraviolet absorbance of polycarbonate were in the same shape of first order exponential decay curve. Accompanied with ultraviolet, the effect of water condensated on the sample on weathering performance of polythene was more significant than that of polycarbonate.

The reaction process of combustion synthesis for TiB₂−Cu was investigated in detail using combustion-wave arresting experiment, X-ray diffraction (XRD) analysis, SEM analysis and differential thermal analysis (DTA). The XRD analysis results for the different parts of the quenched specimen show that TiCu_x intermetallic phase firstly forms with the propagation of combustion wave, and then Ti_1.87B₅₀ and Ti₃B₄ metastable phases come forth due to the diffusion of B atoms and finally the stable TiB₂ phase forms because of the continuous diffusion of B atoms. The formation of TiB₂ phase is not completed by one step, but undergoes several transient processes. The process of reaction synthesis for Ti−B−Cu ternary system can be divided into three main stages: melting of Cu and Ti, and the formation of Cu−Ti melt and few TiCu_x, TiB_x intermetallic phases; large numbers of TiCu_x intermetallic phases formation and some fine TiB₂ particles precipitation; and the TiB₂ particles coarsening and the stable TiB₂ and Cu two phases formation in the final product.

The thermal shock resistance and anti-aluminum erosion of TiB₂-BN multiphase ceramics composites were studied. The experimental results show that the TiB₂-BN multiphase ceramic possesses a good thermal shock resistance at high temperatures (1000, 1200, 1400, 1500°C), with the increasing in thermal shocking temperature, the electro-conductivity of TiB₂-BN ceramics increases. The metal aluminum has a great influence on the properties of TiB₂-BN ceramics and the main reason is that the aluminum reacts seriously with BN. It is suggested that the content of BN should be reduced to the greatest extent.

SnO₂-glaze composites were prepared by Sb-doped SnO₂ and SiO₂−CaO−Al₂O₃−B₂O₃ glaze. The composites changed from an electrical insulator to a conductor as the SnO₂ content increased from Owt% to 90 wt%. The complex impedance spectra of the fabricated composites were investigated in the frequency range of 100Hz-40 MHz and three kinds of typical shape of complex impedance spectra were recorded and analyzed. The spectrum is quite close to the model of conduction via nonohmic contacting when the SnO₂ content is relatively low. In high loading region, the spectrum shows the conduction pattern through ohmic contact chains. In the moderate loading region, the model is a mixture of the above two models. Equivalent circuit of the composite changes from resistor-capacitor circuit to resistor-inductor circuit as the content of SnO₂ increases.

A kind of p-type segmented Bi₂Te₃/CoSb₃ thermoelectric material was prepared by spark plasma sintering (SPS). When the segmented materials were used at the temperature ranging from 300 Koto 800K, the junction temperature was optimized, which is about 500 K, and the corresponding length ratio of CoSb₃ to Bi₂Te₃ is about 15∶2. The measured maximum power output of segmented materials is about 320 W·m⁻², which is about 1.8 times as high as that of monolithic material CoSb₃ under the same measuring conditions.

The effects of fly ash on the compressive strength, pore size distribution and chloride-ion penetration of recycled aggregate concrete were investigated. Two series of concrete mixtures were prepared. The concrete mixtures in series I had a water-to-binder ratio and a cement content of 0.55 and 410 kg/m³, respectively. The concrete mixtures in series II had a water-to-binder ratio and a cement content of 0.45 and 400 kg/m³ respectively. Recycled aggregate was used as 20%, 50%, and 100% replacements of natural coarse aggregate in the concrete mixtures in both series. In addition, fly ash was used as 0%, 25% and 35% by weight replacements of cement. The results show that the compressive strengths of the concrete decreased as the recycled aggregate and the fly ash contents increased. The total porosity and average porosity diameter of the concrete increased as the recycled aggregate content increased. Furthermore, an increase in the recycled aggregate content decreased the resistance to chloride ion penetration. Nevertheless, the replacement of cement by 25% fly ash improved the resistance to chloride ion penetration and pore diameters and reduced the total porosity of the recycled aggregate concrete.

The chemical composition, the content and the leachability of heavy metals in municipal solid waste incineration (MSWI) fly ash were tested and analyzed. It is shown that the leachability of Pb and Cr exceeds the leaching toxicity standard, and so the MSWI fly ash is considered as hazardous waste and must be solidified. The effect of solidifying the MSWI fly ash by cement was studied, and it is indicated that the heavy metals can be well immobilized if the mass fraction of the fly ash is appropriate. The heavy metals were immobilized within cement hydration products through either physical fixation substitution, deposition or adsorption mechanisms.

The influence of calcium sulfate state and fineness of cement on hydration of Portland cement was studied using electrical resistivity measurement. The bulk resistivity curve of the paste from the abnormal cement mainly with hemihydrate had a characteristic abnormal peak and rapid increase in early period. The resistivity measurement technique can be used to discriminate abnormal setting. For normal cement with gypsum, the increase in fineness of the Portland cement decreases the minimum resistivity due to a higher ionic concentration and increases the 24 hour resistivity due to a reduction in macroscopic pore size. The setting time, compressive strength, pore structure of pastes made from different cements were carried out to compare the influence of water to cement ratio, calcium sulfate state and fineness. It is found that the electrical and mechanical properties are strongly affected by the initial porosity, the presence of hemihydrate or gypsum, and the fineness of cement.

By using the uptodate temperatuer-stress testing machine, the thermal expansion coefficient of concrete at early ages was studied and indicative conclusions were achieved: temperature rising due to hydration heat is not directly correlated with cracking, but the temperature and stress evolution process should be taken into consideration in the same time. Proper chemical admixtures and mineral compositions can improve the mechanical properties of concrete such as thermal expansion coefficient, which is very indicative in practice.

The pozzolanic activity of coal gangue burned at different burning temperatures was investigated. The burned coal gangue was mixed with portland cement in different proportions (20%–60%). The pozzolanic activity of coal gangue burned and the hydration, products were examined, the compressive strengths of the pastes of the mixtures were tested, and the mechanism of the reaction was discussed. The experimental results show that the coal gangue burned at 750 °C has the optimum pozzolanic activity, and the burned coal gangue with SiO₂ and Al₂O₃ is in an active form. When the coal gangue burned at 750 °C is mixed into portland cement, the content of calcium hydroxide in paste is significantly reduced, while the contents of hydrated calcium silicate and hydrated calcium aluminate are increased accordingly, hence resulting in the improvement of the microstructure of mortar. The compressive strength of cement paste decreases with increasing the content of burned coal gangue. The decease in strength is small in the range of 20%–30% coal gangue substitution and significant in 30%–60% substitution.

WC-10Co nanocomposite powder produced by spray pyrolysis-continuous reduction and carbonization technology was used, and the vacuum sintering plus sinterhip process was adopted to prepare ultrafine WC-Co cemented carbide. The microstructure, grain size, porosity, density, Rockwell A hardness (HRA), transverse rupture strength (TRS), saturated magnetization and coercivity force were studied. The experimental results show that average grain size of the sample prepared by vacuum sintering plus sinterhip technology was about 420 nm, transverse rupture strength was more than 3460 MPa, and Rockwell A hardness of sintered specimen was more than 92.5. Ultrafine WC-10Co cemented carbide with high strength and high hardness is obtained.

A non-contacting electrical resistivity measurement device used to investigate the effect of different types and contents of mineral admixtures on the hydration performance of mortanrs during early age. The experimental results show that the changes of measured resistivity with time of hydration can be used to describe the hydration characteristics of cement-based materials, as well as the physical and chemical behavior of fly ash; blast furnance slag and silica fume at the very early ages. With an increasing replacement ratio of mineral admixtures, for the specimens blended with fly ash or slag, the resistivity increases firstly, then the following flatting period extends and after setting the resistivity increasing becomes slow and consequently a lower resistivity value at 24 hours occurs. This is due to the dilution effect and lower pozzolanic/hydraulic activity of fly ash and slag. However, for the samples incorporated with silica fume, the resistivity value through 24 hours is lower with shorter flatting period and larger slope in the resistivity curves, which is because of its particle size effect and higher pozzolanic activity of silica fume. Moreover, non-contacting resistivity measurement might provide a helpful information to predict the long term performance including the durability of cement-based materials at early ages.

By using an MTS810 hydra-electro-servo universal machine, the effect of moisture content and temperature on the rate sensitivity of concrete was investigated, the range of strain rate was varying from 1-⁻⁵/s to 10^−0.3/s. It is concluded from the tests that the water content has a significant influence of the rate sensitivity of concrete whereas the temperature has a slight one, and the effects of rate sensitivity are attributed to both the viscosity caused by free water and the transformation of fracture mode when subjected to a high strain rate. The dynamic strength, initial modulus of elasticity, critical strain, Poisson ratio and energy absorption properties were studied systematically. It is found that the strength, initial modulus of elasticity, critical strain, and energy absorption capacity of concrete all increase with the increasing strain rate, whereas Poisson ratio keeps almost unchanged.

As a successive and local plastic deformation process, backward ball spinning was applied for the purpose of producing thin-walled tubular parts with longitudinal inner ribs. According to the local plastic deformation theory, the application of yield criterion to the spinning process and the influence of the radial spinning force component on the formability of inner ribs were analyzed. Based on yield criterion and plastic mechanics, the stable flow rule of metal material and forming criteria of the inner ribs were obtained and conformed to the experimental results so as to contribute greatly to improving the ball spinning process and optimizing the process variables, such as the diameter of ball, the reduction in a pass and the wall thickness of tubular blank, which have a significant influence on the formability of the inner ribs. The knowledge of the influence of the process variables such as the diameter of ball, the reduction in a pass and the wall thickness of tubular blank on the spinning process is essential to preventing the quality defects of the spun parts and obtaining the desired spun parts.

The aim of this article was to provide a systematic method to perform molecular dynamics simulation or evaluation for nano-scale interfacial friction behavior between two kinds of materials in MEMS design. Friction is an important factor affecting the performance and reliability of MEMS. The model of the nano-scale interfacial friction behavior between two kinds of materials was presented based on the Newton's equations of motion. The Morse potential function was selected for the model. The improved Verlet algorithm was employed to resolve the model, the atom trajectories and the law of the interfacial friction behavior. Comparisons with experimental data in other paper confirm the validity of the model. Using the model it is possible to simulate or evaluate the importance of different factors for designing of the nano-scale interfacial friction behavior between two kinds of materials in MEMS.

The gas-solid two-phase flows of the precalciner were simulated by different multiphase models, such as mixture model, the Eulerian model, including mixture and dispersed, and discrete phase model (DPM). The results of the different multiphase models were analyzed and compared, showing the rationality of the diffusion and mixture of the cement raw meals and coal powder to some extent. Moreover, the results also show the rationality of the given inlets' parameters of actual process of the precalciner.

A physically accurate and computationally effective pure finite element method (FEM) was developed to simulate the isothermal resin infusing process. The FEM was based on conservation of resin mass at any instant of time and was objective of resin film infusion (RFI) fiber impregnation and mold filling. The developed computer code was able to simulate the resin infusing visually. A numerical example presented here demonstrated that compared with traditional finite element/control-volume (FE/CV), and FEM was physically accurate and computationally efficient.