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Aluminum powder, stannous oxide powder and cuprous oxide powder are used for the preparation of tin oxide nanostructure in combustion synthesis-injection method with the formula designed using combinatorial chemistry method. The composition range of tin oxide nanostructure synthesis has been studied and the best formula of tin oxide nanowires synthesis has been screened. The research shows that the effective ingredient scope of tin oxide nanostructure is Al=30%~60%, CuO2=10%~50%, SnO=20% ~50% (mol), the main form of tin oxide nanostructure is nanowire and there are also forms such as nanorod, nanoparticle and nanobelt. The formula of tin oxide nanowire which leads to high yield, high purity and high conversion is Al:SnO:Cu2O=4:2:4(mol), the diameter of the tin oxide nanowires is within the range of 10~100 nm and most of them is from 40 to 60 nm, the highest conversion rate of SnO powder to SnO2 nanowire is 25.6%(mass), the tin oxide nanostructure synthesized by combustion synthesis-injection method has high purity, good dispensability, low preparation cost and it is also suitable for mass production.

On the basis of magnesiothermy, with Mg powder, TiO2 powder and B2O3 powder as mixed reactants, relatively pure TiB2 powder was prepared by self-propagating high temperature synthesis (SHS) after leached in diluted hydrochloric acid with the suitable concentration. The product after leached was examined by XRD for qualitative and quantitative analysis, SEM for morphology analysis and infrared spectroscopy for transmittance analysis. It was found that diluted hydrochloric acid could decrease most of the impurities, and the proportion of TiB2 phase in the product is more than 99%, which was hexagonal shape crystal with the grain size of 200-300 nm. Compare with the infrared spectrogram of the middle infrared spectral region of the product of before and after acid pickling, it was found that the transmittance of TiB2 is extremely low in the range of 2000-4000 cm-1, which can be excellent infrared absorption material in the corresponding wave band.

The Ni0.5Zn0.5Fe2O4/PVP composite micro/nanofibers with average diameters of around 300~500nm were prepared by sol-gel method combined with electrospinning technology. The influences of the calcination temperatures (800°C, 900°C, 1100°C) on the crystal structure, micromorphology and microwave absorbing property of the calcined products were characterized by means of XRD, FT-IR, SEM and vector network analyzer. The results showed that the pure spinel structure of Ni0.5Zn0.5Fe2O4 were all formed when the composite micro/nanofibers were calcined at above 800°C. With the increase of calcination temperature, the Ni0.5Zn0.5Fe2O4 grains gradually grown up which contained in the micro/nanofibers, and the micro/nanofiber morphology changed toward the bamboo-like structure, and eventually lost the fiber morphology and presented the irregular granlar forms. In the band of 2~18GHz, the minimum reflectivity of the products moved to high frequency gradually. The microwave absorbing property of the products after being calcinated at 800°Cwas better than being calcinated at 900°C and 1100°C.

Using TiO2B2O3 powders as oxidizer,AlMg powders as reducer,the TiB2 multiphase ceramic are preparated with SHS, and analysed with SEM and XRD.The effect of HCl, H3PO4 to pickling of TiB2-based multiphase ceramics is explored by SEM and XRD analysis. Research suggests that: the main ingredients of TiB2-based multiphase ceramics is TiB2, MgO and MgAl2O4 three phases, few of reaction residual objects and impurities also exists; the multiphase ceramics is forming by many of hexagonal crystal type products and small particles reunion, hexagonal crystal type product is TiB2, small particles may be MgO, MgAl2O4 and other impurities product; MgO can be effectively washed by HCl and H3PO4 , but TiB2 and MgAl2O4 invalid. At room temperature, 30% HCl pickling has the best effect, the concentration of TiB2(ω) is up to 59.3%; the higher of the concentration, the better of acid-effect; In the pickling process, as the temperature rises, the concentration of TiB2 grows, but the temperature should not be too high. When temperature reach 75 °C, HCl volatilizes too quickly and inefficiently. At room temperature, 20% H3PO4 has the best pickling effect, the concentration of TiB2(ω) is up to 52.6%, but the best pickling effect is not well with concentration increasing; as the temperature increasing, purity of TiB2 is also increased; At 70°C, the concentration of TiB2(ω) after H3PO4 pickling is up to 61.9%, refine effect is good.

Titanium powder, silicon powder and carbon powder were used for the preparation of Ti3SiC2 matrix multiphase ceramic by self-propagating high temperature synthesis method (SHS) in air condition. The product was examined by XRD for qualitative and quantitative analysis, SEM for morphology analysis and infrared spectroscopy for transmittance analysis. It was shown in the research that product which was with titanium powder, silicon powder, and carbon powder as raw material was consist of three phases, Ti3SiC2 (76.6 wt%), TiC (21.2 wt%) and TiSi2 (2.2 wt%). TiC phase and TiSi2 phase distributed on the Ti3SiC2 phase matrix of the multiphase ceramic in the form of particles. Ti3SiC2 matrix multiphase ceramic which was with titanium powder, silicon powder, boron carbide powder and carbon powder as the raw material was also consist of three phases, Ti3SiC2, TiC and TiB2. The infrared transmittance in the wave numbers of 1500-4000 cm-1 is less than 15 %. The infrared transmittance of the product with a certain additive in the wave numbers of 600-4000 cm-1 can be dropped below 10 %. Ti3SiC2 matrix multiphase ceramic may be a new high radiation infrared material, which has high temperature resistance, wear resistance and wide band.

TiB2-TiC multiphase ceramics were prepared through altering the molar ratio of Mg and C and leached with suitable acid by the combustion synthesis reaction of Mg, C, TiO2 and B2O3. The samples were investigated by XRD and SEM, and the results showed the diameter of the TiB2 was 1.5μm and the shape of the TiC was irregular spherical particles. The diameter and the proportion of the TiB2 were increased with the increase of Mg powder. The formation mechanism of TiB2 has been studied. The optimized proportioning of the molar ratio of Mg and C was 3:2.

The sleeve-bolt connection and the groove-plate connection are two major forms of bamboo’s joints under tension and compression load, and the strength of these two connections is normally governed by the brittle failure mode of shearing-split. A new configuration of sleeve-cement bamboo joint is designed. Comparative loading tests were carried out to study the static tensile and compressive performances of the bamboo joints. It is found that the joint with sleeve-cement connection behaves more ductile under tension and possesses higher strength under compression than those with the sleeve-bolt and groove-plate connections. The sleeve-cement connection ensures effective transition of the axial load in the bamboo joint, and there are more to be optimized in its design.

Currently, deformations along the central axis of specimens were usually measured under fixed environmental conditions. Seldom were the effects of environmental factors on the drying-shrinkage deformation of cement-based material considered. For this paper, the drying-shrinkage deformation at different w/b ratios and different additions to mortars was investigated under different environments at a temperature of 20 °C and humidity ranging from 100% to 50%. The specimens were cured in water for 28 days before measurement. The results illustrate that mortar shows much less shrinkage under various drying conditions when a lower w/b ratio is adopted. With a decrease in relative humidity the speed of drying-shrinkage becomes gradually lower. The addition of silica fume reduces the drying-shrinkage of mortar under higher relative humidity, because the pore structure of mortar with silica fume becomes more refined. The addition of fly ash increases the total porosity and the volume of coarse pores in the mortar. The drying-shrinkage of mortar under different conditions increases with the addition of more of fly ash.