CaO formed by decomposing CaCO₃ at 1450°C was ground in a vibrational mill, then the long-time ground sample was reheated at different temperatures. Inverse Gas Chromatography (IGC) was used to measure the variation of the sample's surface free energy under grinding and reheoting. It is concluded that the total surface free energy and the London dispersive component of the surface free energy increases with grinding, while the polar component, first increases with grinding, and then decreases, and finally disappears. When the long-time ground sample was reheated, its total surface free energy decreases, among which the London component decreases, but the polar component appears again.

The density function theory and discrete variation method (DFT-DVM) was used to study correlation between composition, structure, chemical bond, and property of thermoelectrics of Bi−Sb−Te series. 8 models of Bi_20−xSb_xTe₃₂ (x=0, 2, 6, 8, 12, 14, 18 and 20) were calculated. The results show that there is less difference in the ionic bonds between Te(I)−Bi(Sb) and Te(II)−Bi(Sb), but the covalent bond of Te(I)−Bi(Sb) is stronger than that of Te(II)−Bi(Sb). The interaction between Te(I) and Te(I) in different layers is the weakest and the interaction should be Van Der Wals power. The charge of Sb is lower than that of Bi, and the ionic bond of Te−Sb is weaker than that of Te−Bi. The covalent bond of Te−Sb is also weaker than that of Te−Bi. Therefore, the thermoelectric property may be improved by adjusting the electrical conductivity and thermal conductivity through chaing the composition in the compounds of Bi−Sb−Te. The calculated results are consistent with the experiments.

One of the main disadvantages of combustion synthesis of ceramic/metal composite materials is the relatively high level of porosity present in the products. To synthesize TiC/Al composites with a dense structure, this paper proposes a novel application of an elevated-temperature Al-melt to directly ignite and simultaneously infiltrate Al−Ti−C preform dipped in the melt. The emphasis was placed on the combustion synthesis process and microstructural evaluation of the preform in the melt, by a liquid quenching test combined with the measurement of the temperature history of the dipped preform. The results show that the combustion synthesis process of the preform in the elevated-temperature melt involves a series of reactions, and that higher temperature of the melt is favourable for the formation of TiC. The synthesized TiC/Al composites exhibit a dense structure, which is attributed to the infiltration of the melt into the preform.

ZrO₂ ceramic was made from evenly dispersed (Y, Ce)-ZrO₂ powder with different compositions, which was prepared by the chemical coprecipitation, and stabilized by compound additions through appropriate techniques. And its mechanical property that is related to the phase content and its microstructure was studied by X-ray diffraction (XRD), scan electron microscope (SEM). The results show that Y₂O₃ has stronger inhibition to the growth of ZrO₂ crystal than CeO₂ has. Therefore, within an appropriate composition range of Y₂O₃ and CeO₂, the higher the content of Y₂O₃, the lower the content of CeO₂, the smaller ZrO₂ crystal. Combining this feature and the stabilization technique with complex additions instead of simple addition, ZrO₂ ceramic with high density and excellent mechanical properties can be made under normal conditions. It is concluded that the improvement of mechanical properties originates from the toughening of microcrack, phase transformation and the effect of grain evulsions.

This paper studies the temperature distribution of BN, an insulating material, sintered in the Spark Plasma Sintering (SPS) system. The temperature distributions of BN at different heating rates were measured, which showed that seeking for an over high heating rate in SPS is not as desirable as controlling of a suitable heating rate in order to have a fast sintering with a uniform temperature distribution.

New layered perovskites, KSr₂Nb₃O₁₀ and two new protonated niobates HSr₂Nb₃O₁₀·1.2H₂O and HSr₂Nb₃O₁₀, were synthesized by solid state reaction and ion-exchange reaction. These new compounds were characterized by EPMA, AAS, XRD, IR, DTA and so on. The structure may be described as treble perovskite sheets [Sr₂Nb₃O₁₀]⁻ interleaved with K⁺, H₃O⁺ or H⁺. These new compounds are new members of the Dion-Jacobsonseries with n=3 for the general formula M[A_n−1Nb_nO_3n+1], and their indexed X-ray powder diffraction data were first reported in the paper.

By using self-made metal-alkoxide yttrium isopropoxide as a sintering additive and disperser of whisker, the SiC whisker reinforced AlN ceramics was prepared. Its apparent density is 99.5 percent of the theoretical density; its flexural strength and fracture toughness are 681 MPa and 5.21 MPa·m^1/2 respectively. Comparing the result with that by applying Y₂O₃ powder as a sintering additive, the flexural strength is increased by 25% and the fracture toughness is increased by 33%. The dispersity of whisker by increased yttrium isopropoxide is significantly better than that by Triton X-100.

The sintering resistance for conductive TiB₂ and non-conductive Al₂O₃ as well as empty die during pulse current sintering were investigated in this paper. Equivalent resistances were measured by current and valtage during sintering the conductive and non-conductive materials in the same conditions. It is found that the current paths for conductive are different from those for non-conductive materials. For non-conductive materials, sintering resistances are influenced by powder sizes and heating rates, which indicates that pulse current has some interaction with non-conductive powders. For conductive TiB₂, sintering resistances are influenced by heating rates and ball-milling time, which indicates the effect of powders activated by spark.

Glasses of BaO−SrO−TiO₂−SiO₂ after electronic radiation treatment of 50–1000 kgy were studied by means of IR spectra, DTA and visible light absorption method. The result shows that the glass structure is changed due to the formation of structure defect from oxygen vacancy and E′ color center which resultsd in the crystallization process and new precursors, and decreasement of T_g temperature and crystallization peaks by 20–50°C.

Doped with Sb and Te, Mg₂ Si based compounds were prepared respectively by solid state reaction at 823K for 8h. Effects of dopants of Sb and Te on the structure and thermoelectric properties of the compounds were investigated. By calculating the values of the electrical conductivity for Sb-doped sample, the mechanism of electric conduction at 625 K is different. The figure of merit for sample doped with 0.4wt% Te at 500K is 2.4×10⁻³W/mK², and it reaches 3.3×10⁻³ W/mK² at 650K for the sample doped with 0.5wt% Sb. The values are more than 1.4 times and 2.3 times of the pure Mg₂Si sample.

Catalytic decomposition of methylene chloride in air below 300°C was studied. Sulfated titania was very effective in converting 959 ppm methylene chloride selectively to CO, CO₂ and HCl. Complete decomposition of methylene chloride was achieved at low temperature (275°C). It was found that the acidic property of catalyst was a determinant factor for the catalytic activity. The presence of water vapor in the feed stream remarkably reduced the catalytic activity, which could be due to the blockage of acidic sites on the surface of catalyst by water molecules. A bifunctional catalyst comprising copper oxide was developed to improve the selectivity of catalytic oxidation, which indicated that copper oxide can promote the deep oxidation of methylene chloride. The crystal form of TiO₂ imposes an important influence upon the catalytic oxidation.

Al−Mn-pillared montmorillonite (AMPM) was prepared by using the artificial Na-montmorillonite from the Qingfengshan bentonite mine as starting materials mixed with Al−Mn pillaring solutions at different Al/Mn molar ratios (R). The basal spacing and specific surface area of the materials were increased significantly compared with untreated clays. When R=0.5, the d(001) value and specific surface area of pillared montmorillonite were 1.8987 nm and 146.01 m² g⁻¹, respectively. The thermal stability was determined using calcined tests, X-ray diffraction (XRD) analysis, thermal gravimetry and differential thermal analysis(TG-DTA). The materials formed at initial R=0.5 exhibited a high stability, the basal interlayer spacing was stabilized at 1.7859 nm after calcined for 2 h at 300°C. The adsorption behavior of the materials was studied by adsorption experiments. The results show the AMPM and calcined Al−Mn-pillared montmorillonite(CAMPM) exhibit a strong capacity of adsorbing the Zn(II) in aqueous solution at pH 10.0.

The sorption behavior of amino methylene phosphonic acid resin (APAR) for In(III) was investigated. Experimental results show that In(III) adsorbed on APAR can be eluted with 2mol·L⁻¹ HCl. The apparent rate constant is k₂₉₈=1.50×10⁻⁵s⁻¹. The sorption behavior of APAR for In(III) obeys the Freundlich isotherm. The thermodynamic parameters of sorption, enthalpy change ΔH, free energy change ΔG and entropy change ΔS of sorption (APAR) for In(III) are 24.1kJ·mol⁻¹, −35.1kJ·mol⁻¹ and 200J·mol⁻¹·K⁻¹, respectively. The coordination molar ratio of the functional group of APAR to In(III) is 2∶1. The sorption mechanism of APAR for In(III) was examined by IR spectrometry.

Four sensing membranes based on fluorescence quenching were prepared by sol-gel method and CA membrane method, and the Ru(II) complexes, Ru(bpy)₃Cl₂ and Ru(phen)₃Cl₂, were used as the indicators. The results indicate that the volume fraction of oxygenϕO₂ have a linear relationship in large scale with tanϕ0/tanϕfor all of the sensing membranes. They have super properties such as excellent limit of detection, fast response time and good reproducibility. The stability of the sensing membranes made by sol-gel method is better than those by CA membranes, but the uniformity of the latter is better than that of the former.

The strength and deformation characteristics of polypropylene fiber reinforced concrete (PFRC) beams were investigated by four-point bending procedures in this paper. Two kinds of polypropylene fibers with different fiber contents (0.2%, 0.5%, 1.0% and 1.5%) by volume were used in the beam, which measured 100×100 mm with a span of 300 mm. It was found that the strength of the reinforced concrete beams was significantly decreased, whereas the flexural toughness was improved, compared to those unreinforced concrete beams. Geometry properties and volume contents of polypropylene fiber were considered to be important factors for improving the flexural toughness. Moreever, the composite mechanism between polypropylene fiber and concrete was analyzed and discussed.

The texture of interfacial zone between cement paste and quartz in the cement-based composites containing polyvinyl alcohol (PVA), methylcellulose (MC) and their polyblend in an amount of 10 wt % with respect to cement, as well as the texture of dehydrated bodies of PVA, MC, and the polyblend solutions, were investigated with SEM. The network texture of the dehydrated polyblend is confirmed by comparing the texture of dehydrated bodies of PVA and MC. The network texture has restrained the movement of polyblend molecules in the cement mortar but is helpful to forming a coherent interface between cement paste and quartz. The key factor of forming the coherent interface is not the neutralization reaction between H⁺ from hydrolysis of quartz and OH⁻ from hydration of cement, but the electrostatic attraction and the chemical reaction between polar groups on the polyblend molecule and cations and anions from hydrolysis of quartz and hydration of cement, respectively. The model of the coherent interface formation is that excessive [HSiO₃]⁻ and [SiO₃]²⁻ anions are bonded with the hydrated cations such as Ca²⁺ and Al³⁺, which is confirmed by the gel containing Ca and Si on the quartz surface.

Blended cement containing blast furnace slag (BFS) and phosphorous slag (PS) is a new kind of cement. The total content of blended materials could increase if two additives were used. Using the same admixtures, the properties of the blended cement with 70% additives could reach the standard of 525-grade slag cement according to GB. The strength of cement with 80% additives could reach the standard of 425-grade slag cement. The tests of strength, pore structure, hydration products, inhibiting alkali-aggregate reaction, resistance to sulfate corrosion of BFS-PSC were performed.

Based on random theory, fluid dynamics, porous media and soil mechanics, the porosity and random characteristic of the two-layer soft soil in Wuhan region were studied in this paper. The random seepage coefficient on the two-layer soft soil was analyzed, and the seepage model and its random distribution function were given. The groundwater flow differential equations related to the two layer soft soil structure were also established. The evaluation procedure of effect boundary on the pumping water in deep foundation pit was put forward. Moreover, with an engineering example, the probability distribution on random boundary prediction for pumping water of foundation pit was computed.

A kind of high impermeable and crack-resistance chemical admixture (HICRCA) was prepared, which is a compound chemical admixture composed of an expansion ingredient, density ingredient, and organic hydrophobic poreblocking ingredient. The results of the experiments indicate that the addition of HICRCA improves mortar and concrete in the following performances: (1) perfect workability: slump is more than 22cm, the slump after 3h is about 16cm; (2) high impermeability: for the mortor, the pervious height under a water pressure of 1.5 MPa is 1.5cm, for the concrete, the pervious height under a water pressure of 5.0 MPa is 2.2cm; (3) high crack-resistance: there is a micro-expansion at the age of 90d; (4) high compressivestrength: compared with the controlled concrete, the compressive strengths at the age of 3d and 28d are improved by 66.4% and 62. 0%, respectively. At the same time, the effects of different curing condition on mortar and concrete expansive and shrinkage performance were studied. In addition, the impermeable and crack-resistance mechanism was investigated in the present paper.

Through the DSC, XRD, SEM and other experimental methods, the microstructure characteristics of reactive powder concrete (RPC) are discussed. The results show that RPC has a super high performance because of its lower ratio of water-binder, high pack density, optimum hydration products mixture and being strengthened by steel fiber. The high performance results from the special hydration microstructure of RPC, and its super performance can be well explained by the centrum particle hypothesis.

An effective analytical approach is developed for the problem of particulate composites containing spherical inclusion with imperfect interface between the matrix and spherical inclusions. In this paper, a general interface model for a variety of interfacial defects has been presented, in which both displacement discontinuity across the interface and the elastic moduli varing with radius outside of the inclusion are considered. The imperfect interface conditions are appropriate in the case of thin coatings on the inclusion. Furthermore, in the case of thin elastic interphase, the displacement field and the stress field in the inclusion and matrix are exactly solved for the boundary problem of hydrostatic compression of an infinite spherical symmetrical body by Frobenius series, and the expression of the normal interface parameter, D_r, is derived. In addition, it has been proved that two previous results derived in some literatures by considering the interface to be a thin interphase with displacement jump or with some variance in its moduli can be reverted from the present formula, respectively. Numerical results are given to demonstrate the significance of the general imperfect interface effects.

The effect of hydrate microcrystals such as calcium silicate hydrates (CSH) and ettringite on the early strength of slag cements was studied. The authors explored the possibility of improving the early strength of the slag cement by applying crystal seed technology. It is shown that slag crystal seeds make the early strength of the cement increased due to the action of hydrate crystal seeds, which speed up the hydration of clinker minerals in the nucleation of ettringite. Therefore, the early strength of the slag cement is obviously improved.

High molecular weight hyperbranched polyarylenes were synthesized in high yields by one-pot copolycyclotrimerizations of 2,5-diethynylthiophene (1), 4,4′-biphenyldiyne (2) and 2,7-diethynylfluorenes (3) with 1-heptyne (4) and 1-dodecyne (5) using TaCl₅·Ph₄Sn catalysts in toluene. The structures and properties of the polymers were characterized and evaluated by IR, NMR, TGA, UV, fluorescence and optical limiting analyses. All the polymers possess high thermal stability and emit strong blue light upon UV irradiation, whose intensities are higher than that from poly(1-phenyl-1-octyne) (PPO), a well-known highly luminescent disubstituted polyacetylene. Little aggregation-induced red shift in the photoluminescence is observed in the thin films of the polymers.

A new method is introduced to study the action between biomaterials and organism. By using an LKB-2277 bioactivity monitor and ampoule method, the fundamental thermogenesis curves of the metabolic process of pk-15 and the toxic effect of three kinds of selenomorpholine compounds on it were studied at 37°C. From the thermogenesis curves, the heat released by pk-15 metabolism was calculated. The results show that the selenium compounds all have toxic action on the metabolism process of pk-15 at the range of experimental concentrations. The sequence of the toxic action of selenium compounds is: Na₂SeO₃>β-(N-selenomorpholine)-ethyl phenylketone hydrochloride>selenomorpholine.

The low melting point metallic tin powder or alloy of tin and lead was blended with polypropylene. A kind of in situ composite has been prepared. The variations of torque were studied when the composites were mixed in Haake torque rheogeniometer. By way of capillary extrusion, effects upon rheology of the in situ composites of the low melting point metals (LMPM) and coupling agent for their different variety and content, were investigated. From flow curves, the results indicate that in situ composites mixed with the LMPM are a kind of pseudoplastic fluid. If the LMPM were melted, the higher the content of the LMPM, the lower apparent viscosity of composites. Meanwhile, when the coupling agent is added into composites, the viscosity of composite will go up first and drop then. This shows that the LMPM have a promoter flow action on the polypropylene.

The substitute of materials based on the materials of the value analysis is a valid path which can lower the cost of products. If the substitute of materials can be applied in Chinese enterprises producing cement, the technique can be advanced, and the remarkable economic performance can also be obtained.

All natural and living systems are governed by atomic and molecular behavior at the nanoscale. Research is now seeking systematic approaches to create revolutionary new products and technologies by control of matter at the same scale. Nanotechnology is expected to have a profound impact on our society. The vision, research and development strategy, and timeline of the nanotechnology initiative are presented by using several recent scientific discoveries, innovations and results from industry. This article demonstrates the implications of innovation for nanotechnology development. To deal with the innovation, a theory of nanotechnology development must come to terms with the developmental, organisational, and strategic dimensions of innovative resource allocation.