Nanosized nickel oxide powders were prepared by thermal decomposition of the nickel citrate gel precursors. The thermal decomposition and powder materials derived from calcination of these gel precursors with various ratios of citric acid (CA) to nickel at different temperatures and times were characterized by thermal analysis (TG/DTA), scanning electron microscopy (SEM), x-ray diffraction (XRD), and measurement of specific surface area (BET) with porosity analyses. The optimized processing conditions of calcination temperature 400 °C for 1 hour with the CA/Ni ratio of 1.2, were determined to produce the nanosized nickel oxide powders with a high specific surface area of 181 m²/g, nanometer particle sizes of 15–25 nm, micro-pore diameter distribution between 4–10 nm. The capacitance characteristics of the nanosized nickel oxide electrode in various concentrations of KOH solutions were studied by the cyclic voltammetry (CV) exhibiting both a double-layer capacitance and a faradaic pseudocapacitance. The nanosized nickel oxide electrode shows a high cyclic stability and is promising for high performance electrochemical capacitors.

A new route to synthesize nanosized crystalline of (La_0.67−XGd _X)Sr_0.33MnO₃ (X=0.05, 0.10, 0.15, 0.20) perovskite-type complex oxides at calcination temperature of 600–1000 °C using the amorphous molecular alloy as precursors was reported. The precursor could be completely decomposed into complex oxide at temperature below 500 °C according to the TGA and DTA results. XRD demonstrates that the decomposed species is composed of perovskite-type structure at calcination temperature of 600 °C for 2 h. The particle size that depends on the calcination temperature of the precursor is in a range of 30–120 nm as determined by transmission electron microscopy (TEM). This method is effective and can be easily quantitatively controlled to synthesize nanosized perovskite-type complex oxides. The magnetic properties of (La_0.67−XGd _X)Sr_0.33MnO₃ nanocrystalline were preliminary studied.

An approach was presented to characterize the stress response of workpiece in hard machining, accounting for the effect of the initial workpiece hardness in addition to temperature, strain and strain rate on flow stress in this paper. AISI H13 die steel was chosen to verify this methodology. The proposed flow stress model demonstrates a good agreement with experimental data. Therefore, the proposed model can be used to predict the corresponding flow stress-strain response of AISI H13 die steel with variation of the initial workpiece hardness in hard machining.

The effects of two-stage aging and retrogression and reaging heat treatment on the fracture toughness and stress corrosion cracking resistance of 7475 alloy were studied. The fracture toughness, conductivity and strength of samples of nine groups under duplex aging conditions and three retrogression and reaging heat treatments were also measured. Incorporating the microstructure and property, we found that when the condition of the first order aging kept identical, the fracture toughness and stress corrosion cracking resistance increase with aging time and the second aging temperature. The optimal treatment conditions are (115°C×7h+185°C×13h) among all tested two-stage aging treatments. Although the 7475 alloy treated by RRA method shows the highest strength and its stress corrosion cracking resistance after twenty minutes retrogression can also reach the same level as those by the optimal treatment of (115°C×7h+185°CsX13h), the fracture toughness is even low.

The effect of annealing on microstructure, adhesive and frictional properties of GeSb₂Te₄ films were experimentally studied. The GeSb₂Te₄ films were prepared by radio frequency (RF) magnetron sputtering, and annealed at 200 °C and 340 °C under vacuum circumstance, respectively. The adhesion and friction experiments were mainly conducted with a lateral force microscope (LFM) for the GeSb₂Te₄ thin films before and after annealing. Their morphology and phase structure were analyzed by using atomic force microscopy (AFM) and X-ray Diffraction (XRD) techniques, and the nanoindention was employed to evaluate their hardness values. Moreover, an electric force microscope (EFM) was used to measure the surface potential. It is found that the deposited GeSb₂Te₄ thin film undergoes an amorphous-to-fcc and fcc-to-hex structure transition; the adhesion has a weaker dependence on the surface roughness, but a certain correlation with the surface potential of GeSb₂Te₄ thin films. And the friction behavior of GeSb₂Te₄ thin films follows their adhesion behavior under a lower applied load. However, such a relation is replaced by the mechanical behavior when the load is relatively higher. Moreover, the GeSb₂Te₄ thin film annealed at 340 °C presents a lubricative property.

The isothermal and cyclic oxidizing kinetics of Co-40Cr alloy and its yttrium ion-implanted samples were studied at 1000°C in air by thermal-gravity analysis (TGA). Scanning electronic microscopy (SEM) was used to examine the Cr₂O₃ oxide film’s morphology after oxidation. Secondary ion mass spectroscopy (SIMS) method was used to examine the binding energy change of chromium caused by yttrium doping. Acoustic emission (AE) method was used in situ to monitor the cracking and spalling of oxide films formed on both samples during oxidizing and subsequent air-cooling stages. It is found that yttrium implantation remarkably reduces the isothermal oxidizing rate of Co-40Cr and improves the anti-cracking and anti-spalling properties of Cr₂O₃ oxide film. The reasons for the improvements are mainly that implanted yttrium reduces the grain size of Cr₂O₃ oxide, increases the high temperature plasticity of oxide film, and remarkably reduces the number and size of Cr₂O₃/Co-40Cr interfacial defects.

To abtain large crystals for improving the physical and optical properties of materials, the crystal of Yb-doped S-FAP was sythesized by the Czochralski method, the growth process was analyzed, and its structure was determined. This material was confirmed to have a hexagonal structure, unit-cell parameters (a=b=0.9683(4) nm, c=0.7277(4) nm) are slightly different from the crystal parameters of S-FAP reported before.

The effect of electron beam on the microstructures and phase transformation of nanostructured TiO₂ heat treated at various temperatures for different time was studied by in-situ TEM and SAED. Anatase ex-situ heated at 250 °C and 360 °C transformed to rutile while irradiated by the electron beam. With the increasing sizes and distribution of the powders on the amorphous carbon, the process of phase transformation by the electron beam was encumbered. These evolutions may be due to the changes of vacuum atmosphere and the properties of powders.

The graphite encapsulated α-Fe particles were prepared by reduction of stage-2 and stage-3 FeCl₃ graphite intercalation compounds (GICs) with metallic potassium. X-ray diffraction analysis (XRD), energy dispersive X-ray spectroscopy (EDS) investigation and transmission electron microscopy (TEM) observation show that the reduction products of stage-2 FeCl₃-GICs contains more abundant α-Fe nanoparticles than those of stage-3. High-resolution TEM (HRTEM) observation reveals that the nanoparticle of α-Fe was polycrystals or twins, which was real or quasi two-dimension in shape, and whose space orientation was strictly controlled by the graphene. Based on the experiment results, a possible growth model of the graphite encapsulated α-Fe was proposed.

In order to avoid forming an electrical conductive network due to surface connections, the magnetic metal fibers were coated with SiO₂ for surface modification by the sol-gel process. The microstructure, composition and electromagnetic characteristics of SiO₂-coated and uncoated metal fibers were studied using SEM, EDAX, and a voter network analyzer. The reflectivity was simulated using the RAMCAD software. The electromagnetic parameters and absorption properties of SiO₂-coated metal fibers were improved greatly due to optimal impendence matching and the electric conductivity decreased, compared to those of uncoated materials.

Four types of steel sheets containing 0.04%, 0.09%, 0.14% and 0.36% Si, respectively, were electrodeposited with a nickel layer of 3 μm in thickness and then galvanized in molten Zn at 450°C for various periods of time. The formation and growth of intermetallic compound layers on the surface of the samples were investigated by SEM and EDS. The experimental results show that the method of Ni-electrodeposited pretreatment can distinctively restrain the over-growth of the galvanized coatings of reactive steels and get eligible coatings with a proper thickness, bright appearance and strong adherence. EDS results indicate that a series of Ni-Zn intermetallic compounds γ′, γ and δ ₂ are first formed on the surface of the samples. With a prolonged immersion time, the Γ₂-Fe-Zn-Ni and δ-Fe-Zn are formed accompanied by the gradual disappearance of γ′, γ and δ ₂ layer. After a longer immersion time, the lumpy ζ-Fe-Zn occurs between δ and liquid Zn and the Γ-Fe-Zn does between steel substrate and δ. Subsequently, ζ is in the form of a continuous and compact layer. The method of Ni-electrodeposited pretreatment changes the formation of Fe-Zn intermetallic compounds, which delay the growth of lumpy ζ and promote the growth of compact δ. Consequently, the abnormal growth of reactive steels is eliminated.

The foamed aluminum alloys with different densities were fabricated by melt foaming technique. The compressive properties and energy absorption of the foamed aluminum alloy with different densities were analyzed. The results reveal that the compressive stress-strain curves follow the typical behavior of cellular foams with three deformation stages. Under the same strain, the energy absorption capability decreases with the decrease of density. However, with increasing the strain, the energy absorption efficiency of foamed metal increases initially and then decreases. The lower the density, the longer the plateau region, within the range of high strain, the energy absorption efficiency is always high.

This paper studied the appearance transition of microdischarges, the phase composition and the morphology evolution of the oxide film formed by microarc oxidation on AZ91D magnesium alloy. The appearance of microdischarges population experienced apparent changes in size, spatial density and color, which was related with the changes of the type and quantity of the disintegrated gas bubbles generated at the interface between the electrolyte and substrate. Correspondingly, the diameter of micropores together with net-like fine microcracks increased when a higher voltage was employed. The coating was composed of MgO, MgAl₂O₄ and there existed a fluoride-enriched zone of about 3–5 μm at the film/substrate interface.

A novel carbon-sulfur nano-composite material was synthesized by heating sublimed sulfur and high surface area activated carbon (HSAAC) under certain conditions. The physical and chemical performances of the novel carbon-sulfur nano-composite were characterized by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) and X-ray diffraction (XRD). The electrochemical performances of nano-composite were characterized by charge-discharge characteristic, cyclic voltammetry and electrochemical impendence spectroscopy (EIS). The experimental results indicate that the electrochemical capability of nano-composite material was superior to that of traditional S-containing composite material. The cathode made by carbon-sulfur nano-composite material shows a good cycle ability and a high specific charge-discharge capacity. The HSAAC shows a vital role in adsorbing sublimed sulfur and the polysulfides within the cathode and is an excellent electric conductor for a sulfur cathode and prevents the shuttle behavior of the lithium-sulfur battery.

The polyoxometalate (CPFX·HCl)₃H₃PW₁₂O₄₀·8H₂O was prepared and characterized by elemental analysis, IR spectra and TG-DTA-DTG. The thermal decomposition mechanism and non-isothermal kinetic parameters of the polyoxometalate were obtained from the analysis of TG-DTG data using the Achar equation, Coats-Redfern equation (CR), Madhusudanan-Krishnan-Ninan equation (MKN) and Horowitz-Metzger equation (HM). And their mathematical expressions of the kinetic compensation effect were also calculated.

The intercalation of drug molecules with montmorillonit (MMT) using Acyclovir (ACV) as the model drug was focused on. The optimum conditions were studied based on orthogonal design, such as intercalation time and temperature. The intercalation composites were characterized by X-ray diffraction (XRD), Fourier transformed infrared (FT-IR), and thermogravimetric analysis (TGA). The experimental results reveal that ACV is successfully intercalated into the interlayers of MMT. The in vitro release experiments reveal that ACV is released from MMT steadily and pH dependent

LaNiC₂ was synthesized by a solvothermal route in a stainless steel autoclave at 600 °C. In this process, nickel chloride, lanthanum chloride and toluene were used as raw materials, and metallic Na and Li alloy were used as reductant. The products were characterized with an X-ray diffractometer (XRD) and a scanning electron microscope (SEM). The LaNiC₂ products consisted of a great deal of micro-rods. The micro-rods had diameters ranging from hundreds of nanometers to several micrometers and lengths ranging from several micrometers to tens of micrometers.

The toughening of the diglycidyl ether of bisphenol A epoxy resin with isocyanateterminated polyethers (ITPE) was investigated. The progress of the reaction and the structural changes during modification process were studied using FTIR spectroscopy. The studies support the proposition that TDI (tolylene diisocyanate) acts as a coupling agent between the epoxy and polyethers, forming a urethane linkage with the former and the latter, respectively. Me THPA-cured ER/ITPs blends were characterized using dynamic mechanical analysis (DMA) and thermogravimetric analysis (TGA). It is indicated the glass transition temperature (T _g) of systems was lower than the T _g of pure epoxy resin and overfull ITPE separated from the modified epoxy resin and formed another phase at an ITPE-content of more than 10wt%. The thermal stability was decreased by the introduction of ITPE. The impact strength and the flexural strength of the cured modifiedepoxy increased with increasing the ITPE content and a maximum plateau value of about 24.03 kJ/m² and 130.56 MPa was measured in 10wt% ITPE. From scanning electron microscopy (SEM) studies of the fractrue surfaces of ER/ITPE systems, the nature of the micromechanisms responsible for the increases in toughness of the systems was identified.

The emulsion polymerization of highly shear-stable copolymer dispersions of methyl methacrylate and butyl acrylate were carried out using poly (vinyl alcohol) with a thiol end group (PVA-SH) as protective colloid. The dispersions can be transformed into corresponding redispersible powder via a spray drying-cooling process. On-line FT-IR monitoring shows that grafting polymer of PVA-g-PMMA was formed mainly at the stage-1 of the emulsion polymerization. TEM images show, the PVA-SH shell was fragmentary when adding SDS at initial stage and integrated when adding at particle growing or final stage. The particle size turns to be smaller when delayed adding SDS surfactant. Triethanolamine, a co-regulator of PVA-SH, controlled the M _n to 50 000–70 000 and reduced the PDI to 1.5–1.7. The acrylic dispersions with 0.8wt%–1.5wt% PVA-SH₁ can be spray-dried into super dispersible polymer powder (SDPP), which can easily disperse in water and form reconstituted dispersions with an average particle size smaller than 1 micron.

Employing carbonyl iron powder and Ethylene-Propylene-Diene Monomer (EPDM) as the absorbent and matrix, rubber radar absorbing materials (RAM) were prepared. Effects of the carbonyl iron volume fraction and the thickness of the RAM on the microwave absorption properties in the frequency range of 2.6–18GHz were studied, and a mathematical analysis was made using the electromagnetic theory. The experimental results indicate that the minimum reflectivity of the radar absorbing materials continuously decreases with the increase of the carbonyl iron volume fraction, and the absorption peak also moves towards the low frequency for the same thickness of the RAM. The minimum reflectivity of the 3.0 mm RAM is −21.7dB at 3.5 GHz when the volume fraction of carbonyl iron is 45%. The reflectivity of the RAM is not in direct proportional to the thickness of the RAM, when the RAM has the same volume fraction of the carbonyl iron. The reflectivity of the RAM presents a regular trend at a given carbonyl iron volume fraction in the frequency range of 2.6–18 GHz. With the increase of the thickness, the maximum absorption peak moves towards low frequency band, the minimum reflectivity firstly decreases and then increases, and the absorption bandwidth for reflectivity<−10 dB firstly increases and then decreases. The microwave absorption properties of the RAM are determined by the thickness and the composition of the radar absorbing materials. Theoretical analysis indicates that the reflectivity of the RAM is determined by the matching degree of the air’s characteristic impedance and the input impedance.

Acetanilide, adipic acid and potassium hydrogen phthalate were chosen as nucleating agents of polyvinyl chloride(PVC), and their effects on PVC crystallization were studied by differential scanning calorimetry, wide angle X-ray diffraction and fourier transform infrared spectroscopy. The experimental results indicate that all of the three additives are compatible with PVC to some extent, but adipic acid’s compatibility with PVC is less satisfactory. The three additives can improve PVC crystallinity, and acetanilide can decrease PVC glass transition temperature(T _g)and narrow PVC melting range, while adipic acid and potassium hydrogen phthalate rise T _g of PVC and widen its melting range. All additives do not affect PVC crystal system and all samples are in orthorhombic system. All additives can improve (200), (110), (210) and (201, 111) planes growing. Moreover, acetanilide and adipic acid can shrink PVC spacings and improve the crystal perfection of PVC, but potassium hydrogen phthalate swells spacings and reduces the perfection of PVC crystal.

A novel polyarylene sulfide, polyarylene sulfide sulfone imide, was polymerized with a new monomer (Dichlorodiimide) and sodium sulfide by taking high temperature (200 °C) N-methyl-2-pyrrolidinone (NMP) as solvent. The polymer was characterized by using conventional methods. Physical properties of the polymer, including thermal stability and solubility, were also studied. DSC and TG analyses reveal that the glass transition temperature T _g is equal to 252.4 °C and that the thermal decomposition temperature T _d is equal to 484.9 °C.

A new method of fabricating porous polymer scaffolds was developed, using sodium hydrogen carbonate particulates as the porogen to foam. The pore structure of polymer scaffolds can easily be manipulated by controlling the size and weight fraction of sodium hydrogen carbonate particulates. The scaffolds are highly porous with a porosity greater than 90% and with a larger pore size ranging from 100–400 μm, and are well distributed with the interconnected and open pore wall structure which is necessary for tissue engineering. We investigated the effect of the porosity of scaffolds, the pore size of scaffolds and material of polymer on the mechanical properties of scaffolds. The scaffolds fabricated by the method have more big pores than those by the convenient method of salt leaching.

To evaluate the biocompatibility of poly(lactic acid/glycolic acid/ asparagic acid-co-polyethylene glycol)(PLGA-[ASP-PEG]) tri-block copolymer in vitro, L929 fibroblast was co-cultured with the copolymer for cytotoxicity, hemolysis and pyrogen tests. And, compared with PLGA, the adhesiveness rate of the copolymer was calculated. The experimental results show that the toxicity gradation of the material was 0–1; L929 fibroblasts had a good cell morphology and proliferated rapidly on the surface of the material; hemolysis ratio was 3.08%; there was no pyrogen reaction. The adhesiveness of PLGA-[ASP-PEG] was better than that of the PLGA’s(P<0.05). The results confirm that the PLGA-[ASP-PEG] has a good biocompatibility.

Many particles are found in the cytoplasm area after the mixture of hydroxyapatite (HAP) nanoparticles and cultured cancer cells. The purpose of this study was to confirm whether these particles in cytoplasm are HAP nanoparticles exactly. BEL7402 cells were incubated in HAP sol for 8 hours. Then, the cells were collected for specimen preparation. Transmission electron microscope (TEM), energy dispersing spectrum (EDS) and electronic diffraction (ED) attached to TEM were used to detect the properties of the particles. It is found that many particles similar to HAP in shape are in the cytoplasm under TEM. By EDS analysis, they are the particles containing calcium (Ca) and phosphorus (P). The classic rings of HAP crystal appear in the ED pictures of these particles. So the particles are confirmed as HAP nanoparticles. Thus, it is concluded that HAP nanoparticles as the crystal particles can be absorbed by hepatoma cells.

Using spark plasma sintering(SPS) technique, TiC particle reinforced γ-TiAl composites were prepared with varying weight fraction of TiC powders. The effects of the TiC fractions and distributions on the properties of the composites were investigated. The composite containing 7wt% TiC had the optimum three-point bending strength of 842 MPa, which was 200 MPa greater than that of the unreinforced γ-TiAl intermetallic. The degradation of the bending strength occurred in the composites containing more than 7wt% TiC and this was believed to be attributed to agglomerated particles of TiC, which acted as crack initiation and propagation sites. The increase of strength in TiC reinforced IMCs came from the grain refinement and the interaction of dislocations with the reinforcing particles. The bending strength of the IMC containing 7wt% TiC was theoretically estimated to increase by 85 MPa and 200 MPa, respectively, by the grain refinement and dislocation strengthening, the total of which was almost in accordance with the improvement in that of the unreinforced γ-TiAl intermetallic when considering normal estimation errors.

The titled high performance foamed concrete was developed from Portland cement, ultra fine granulated blast-furnace slag, pulverized fly ash and condensed silica fume by means of pre-foaming process. The resultant foamed concrete presents its thermal conductivity of about 0.16–0.75 W/(m · °C) and 28 d compressive strength of about 1.1–23.7 MPa when its mix proportion varies in the range of cement content 280 kg–650 kg/m³, fly ash 42–97 kg/m³, slag 64–146 kg/m³, silica fume 34–78 kg/m³, and sand 0–920 kg/m³. The compressive strength of the foamed concrete with oven dried bulk density of 1500 kg/m³ in appropriate mix proportion and with small amount of superplasticizer reached as high as 44.1 MPa. Meanwhile, the fresh foamed concrete behaves like an excellent flow-ability, therefore, is especially suitable for the application in case of massive foamed concrete casting in situ and in the case of filling casting into large volume underground irregular voids, except for pre-casting of building components like blocks, bricks, and wall panels.

By using Nb and Si elemental powders as raw materials, dense Nb/Nb₅Si₃ composites were successfully fabricated by a spark plasma sintering (SPS) technology. The microstructure of the fabricated composites was analyzed by OM, SEM, XRD and EPMA; the microstructure evolution of the composites was also investigated by a quenching test. The experimental results show that the prepared composites consist of Nb and Nb₅Si₃ phases; Nb particle uniformly distributes in the in-situ synthesized Nb₅Si₃ matrix. During the SPS process, an interfacial reaction occurs between Nb and Si particles to synthesize Nb₅Si₃ until reactant silicon has been completely depleted.

Grafting of polystyrene (PS) onto titanium dioxide powder was investigated. The graft polymerization reaction was induced by high frequency discharge produced N₂ plasma treatment of the surfaces of titanium dioxide. IR, XPS and TGA results show that PS was grafted on the titanium dioxide powder. And the crystal structure of the titanium dioxide powder observed by XRD was unchanged after plasma treatment.

LiCo _xMn_2−xO₄ cathode materials for lithium ion batteries were synthesized by mechanical activation-solid state reaction at 750°C for 24 h in air atmosphere, and their crystal structure, morphology, element composition and electrochemical performance were characterized with XRD, SEM, ICP-AES and charge-discharge test. The experimental results show that all samples have a single spinel structure, well formed crystal shape and uniformly particle size distribution. The lattice parameters of LiCo _xMn_2−xO₄ decrease and the average oxidation states of manganese ions increase with an increase in Co content. Compared with pure LiMn₂O₄, the LiCo _xMn_2−xO₄ (x=0.03–0.12) samples show a lower special capacity, but their cycling life are improved. The capacity loss of LiCo_0.09Mn_1.91O₄ and LiCo_0.12Mn_1.88O₄ is only 1.85% and 0.95%, respectively, after the 20th cycle. The improvement of the cycle performance is attributed to the substitution of Co at the Mn sites in the spinel structure, which suppresses the Jahn-Teller distortion and improves the structural stability.

The effects of Pb content on crystallographic phase, microstructure, electric-properties of PMSZT piezoelectric ceramics were studied. The crystallographic phase and microstructure of the ceramics were examined by using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The experimental result shows that the samples consist of a mixture of tetragonal and rhombohedral phases in the range of lead contents x=0.95–1.06, grains grow up homogeneously and the minimum value of Curie temperature was obtained with x=1.02. With Pb content x<1.02 or x>1.02, the Curie temperature moves towards a high temperature. A well-situated electric-properties of ɛ ^T ₃₃/ɛ ₀ (1660), d ₃₃ (344pC/N), K _p (0.684), Q _m (2350),tan δ(0.0030) were obtained when lead content x=1.02.

The structural, dielectric and piezoelectric properties of (1−x)(Bi_1/2Na_1/2) TiO₃-xBaTiO₃ ceramics were investigated for the compositional range, x=0.02, 0.04, 0.06, 0.08, 0.10. The samples were synthesized by a conventional solid-state reaction technique. All compositions show a single perovskite structure, and X-ray powder diffraction patterns can be indexed using a rhombohedral structure. Lattice constants and lattice distortion increase while the amount of BaTiO₃ increases. The X-ray diffraction results show the morphotropic phase boundary (MPB) of (1−x)(Bi_1/2Na_1/2) TiO₃-xBaTiO exists in near x=0.06−0.08. Temperature dependence of dielectric constant ɛ ^T ₃₃/ɛ ₀ measurement reveals that all compositions experience one structural phase and two ferroelectric phases transition below 400 °C: rhombohedral (or rhombohedral plus tetragonal) ferroelectric phase ↔ tetragonal antiferroelectric phase ↔ tetragonal paraelectric phase. Relaxor behaviors exist in the course of ferroelectric to antiferroelectric phase transition. Dielectric and piezoelectric properties are enhanced in the MPB range for (1−x)(Bi_1/2Na_1/2)TiO₃-xBaTiO₃.

Heteropoly acid of Keggin structure phosphotungstic(HPW) and phosphomolybdic(HPMo) were chemically anchored to the modified SBA-15 channel. The materials were used as catalyst for oxidative desulfurization of organic sulfur compounds including benzothiophene (BT), dibenzothiophene (DBT) and 4,6-dimethydibenzothiophene (4,6-DMDBT). The experimental results show that the catalysts are efficient and reusable, the catalytic activity is hardly reduced even in the 5th cycle of use.

A ternary-layered carbide Ti₂AlC material could be synthesized by spark plasma sintering(SPS) technology using elemental powder mixture of Ti, Al and active carbon. By means of XRD and SEM, phases were identified and microscopically evaluated. The experimental results show that the main phase in the product was fully crystallized Ti₂AlC with small particle size when sintered at 1200 °C. The synthesis temperature of SPS was 200–400 °C lower than that of hot pressing (HP) or hot isostatic pressing (HIP). Through thermodynamics calculations, the mechanism of Ti₂AlC was studied by calculating changes of Gibbs free energy of reactions.

Measurements of crystal structures, electrical and magnetic properties for the electron doped Bi _xCa_1−xMnO₃ (0<x≤0.33) reveal the presence of a variety of notable changes in correlation with magnetic transitions and charge ordering. Samples with x<0.2 in general show a clear ferromagnetic transitions around 130 K. On the other hand, samples with 0.2≤x≤0.33 show much more complex low-temperature magnetic properties perhaps due to the coupling between the magnetic states and orbital/charge ordering. Structural transformations and structural modulations in the x=0.25 and 0.33 samples have been observed by transmission electron microscopy.

(Nd_0.01Y_0.99)₃Al₅O₁₂ nano-sized powders were synthesized by low temperature combustion (LCS), using Nd₂O₃, Y₂O₃, Al(NO₃)₃·9H₂O, ammonia water and citric acid as starting materials. The powders were characterized by TG-DTA, XRD, FT-IR, ICP and TEM, respectively. The grain sizes were calculated by the Scherrer’s formula using the full width at half maximum (FWHM) of YAG (420) crystal plane diffraction lines. The study focused on crystallization of ceramics at different heat treatment temperatures. The experimental results show that crystallizing temperature of YAG is 850 °C, and the intermediate crystal phase YAP, appearing during heat treatment, transforms to YAG cubic crystal phase at the temperature of 1 050 °C. The particle size of the powders synthesized by LCS is nano-sized. With the temperature increasing, the mean grain sizes raise, the stand deviations keep almost at the value of 2.0 and the lattice parameters decrease. The grains mainly grow by grain boundary diffusion. The lattice parameter expansion is caused by an increase of the repulsive dipolar interactions on surfaces of crystallites.

The chemical structures of four types of superplasticizers (SPs) and their adsorptive behaviors on β-C₂S were investigated. The adsorption properties of SPs on β-C₂S were measured and the relationship between the adsorption quantity and the specific surface of β-C₂S was analyzed. The experimental results show that the adsorption quantity increases with the surface area increase of β-C₂S, but the adsorption quantity per surface area is similar, which means that the main adsorbent is β-C₂S itself. Polycarboxylic ester (PCE) showed the highest adsorption amount on β-C₂S, followed by β-naphthalene sulfonates (NSF) and formaldehyde-acetone condensates sulfonates (FAS), amino sulphonate (AS) showed the least adsorption amount on β-C₂S. PCE affected the surface potential of β-C₂S particles in water differently in comparison with other types of SPs. The adsorption capacity of SPs on β-C₂S is determined by factors such as molecular structure, functional groups and molecular weight of SPs.

Combining with the technology of self-compacting concrete, self-stressing concrete and concrete-filled steel tube, we can get self-compacting and self-stressing concrete-filled steel tube. In order to study the expansive mechanism of self-stressing concrete, the continuous observation of 47 days on six specimens was carried on. The specimens have different steel area to concrete area ratio. The expansive process in hoop and axial direction were studied, and the expansive mechanism was discussed too. The experimental results identify that the creep and elastic deformation take a large proportion in effective free expansion. The calculating formulas of self-stress in hoop and axial directions were presented here.

This paper discussed two methods to enhance the electrical conductivity of the carbon fiber(CF) electrically conductive concrete. The increase in the content of stone and the amount of water used to dissolve the methylcellulose and marinate the carbon fibers can decrease the electrical resistivity of the electrically conductive concrete effectively. Based on these two methods, the minimum CF content of the CF electrically conductive concrete for deicing or snow-melting application and the optimal ratio of the amount of water to dissolve the methylcellulose and marinate the carbon fibers were obtained.

To investigate the early-age behaviors of concrete under a restrained condition, a set of apparatus was developed. In this way, the tensile creep and other early-age properties can be investigated in depth. By measuring the modulus of elasticity of concrete, synchronous shrinkage of concrete and steel rings and free shrinkage of concrete, the deformations of concrete ring can be quantified respectively. The experimental results show the tensile stress in concrete is time-dependent, and the stress at cracking is much lower than the tensile strength at that age; the tensile creep plays an important role in relaxing the tensile stress and postponing the cracking of concrete.

The influence of reinforced bar corrosion on the bond degradation in lightweight concrete was studied. Accelerated constant current corrosion tests were performed on lightweight reinforced concrete samples, and the influential factors, such as protective layer thickness, reinforced bar diameter and corrosive level were investigated. The constant current step method was used to measure the electric resistance of the concrete protective cover, which was used to characterize the corrosion level of the rebar. Experimental results indicated that the corrosive resistance increased with increasing the cover dimension and decreasing the reinforced bar diameter, and the rate of decrease in the specimen impedance after cracking depended on the cover dimension. A new medium was offered for the further research on the performance degradation of corrosion lightweight concrete.

The effects of polynaphthalene series superplasticizers(PNS) with a low content of sodium sulfate (H-UNF),with a high content of sodium sulfate(C-UNF) and polycarboxylate type superplasticizer (PC) on strength and shrinkage cracking of cement mortar under drying conditions were investigated by means of multi-channel ellipse ring shrinkage cracking test, free shrinkage and strength test. The general effect of PNS and PC is to increase the initial cracking time of mortars, and decrease the cracking sensitivity of mortars. As for decreasing the cracking sensitivity of mortars, PC>H-UNF>C-UNF. To incorporate superplasticizers is apparently to increase the free shrinkage of mortars when keeping the constant w/b ratio and the content of cement pastes. As for the effect of controlling the volume stability of mortars, PC>C-UNF>H-UNF. Maximum crack width of mortars containing PC is lower, but the development rate of maximum crack width of mortars containing H-UNF is faster in comparison with control mortars. The flexural and compressive strengths of mortars at 28-day increase with increasing superplasticizer dosages under drying conditions. PC was superior to PNS in the aspect of increasing strength.

The structure and properties of lithium aluminosilicate glasses containing Y₂O₃ were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), differential thermal analysis (DTA) and Raman spectroscopy. Effects of yttria on the viscosity of LAS glasses were investigated, and found that the introduction of yttria effectively decreased the viscosity of LAS glasses. In Raman spectra of initial glasses it is shown the starting glasses are in almost complete disorder, since all bands are weak and broad. In the spectra of heat-treated specimens some new narrow bands appear and increase in intensity, and the frequency changes with varied yttria addition. The DTA and XRD results show that yttria controlled the crystallization of LAS glasses by increasing the crystallization peak temperature (T _p), however, the main crystalline phase of glass-ceramics was β-spodumene.

The modulus deviation of base material calculated from the data of falling weight deflectometer (FWD) was used to evaluate the uniformity of road base so as to reflect the construction quality. Four parameters, the repeatability standard deviation of the data in the same driveway, the reproducibility standard deviation of the data in the different driveway, the consistency statistics value of the data in the different driveway, and the consistency statistics value of the data in the same driveway, were introduced for the construction uniformity analysis. The experimental result shows that the materials modulus calculated from FWD has a highly correlative relationship with the uniformity of road base.

The effect of steel fibre used in concrete was systematically analyzed by model testing of 30 2-pile thick caps of steel-fibre reinforced concrete, in which the model scale was 1:5. The experiment system composed of a loading device, strain measurement system and a data-acquisition system was used, also an electromechanic centigrade scale, a lens and a YJ-25 static resistance strainometer were used. The experimental results show that the volumetric rate of steel fibre and draw ratio have an important influence on its load-bearing capacity. The incorporation of steel fibre can effectively improve the extension and reduce the thickness of the caps.

Using Geogrid-Reinforced Soil (GRS) we studied the working mechanism and design method of GRS at bridge approach with high backfill by field experiment. In a highway section where the height of backfill is 13.5 meters, geogrids were used at two bridge approaches to address the bumping problems. Some soil pressure cells were used to measure the normal and lateral soil pressure at different locations in the roadbed. The experimental results indicate that geogrids in geogrid-reinforced soil (GRS) could produce an uplift force, the closer the location to the abutment, the larger the uplift force, and the reduction of measured soil pressures compared with theoretical values was the largest at the bottom of roadbed, less at the top than at the bottom, and the least in the mid-height of roadbed than at the bottom. These findings are different from those of the traditional greogrid-reinforced subgrade design method.

Several kinetic models for unsaturated polyester cure reaction and some existing parameter estimation techniques of these models were introduced. Correlated kinetic parameters and kinetic equations of the autocatalytic empirical kinetic model of LPSMC system were determined by using isothermal DSC to scan the system which was thickened by crystalline polymer (PEG-MAH). Through using a serial curing degree of the system to validate the model, the experimental results were basically identical with the predictions of the autocatalytic empirical kinetic model. This model could provide a theoretical reference to the determination of molding techniques of low pressure SMC.

The environment-friendly glasses which integrate function and structure were introduced, among these glasses can save energy very efficiently due to its low infrared emissivity. The fundamental principle of the low emissivity glass and the research progress of this kind glass were analyzed. Meanwhile, high performance and low applied development trend of emissivity glass were reviewed.