The microstructures and electrical properties of Bi_0.5(Na_1−x−yK _xLi _y)_0.5TiO₃ lead-free piezoelectric ceramics were studied. These ceramics were prepared by conventional ceramic technique. XRD analysis reveals that the ceramics possess almost pure perovskite phase when y⩽0.2. The SEM results show that, with more amounts of Li⁺, the crystalline grain growing speed is accelerated, and the sintering temperature can effectively be decreased. The measurements of piezoelectric properties indicate that the ceramics with relatively low amount of Li⁺ and high amount of K⁺ have comparatively large piezoelectricity. The dielectric measurements show that the ceramics have properties like relaxor ferroelectrics and diffuse phase transition (DPT) at T _d and T _c, respectively. The results of ferroelectric measurements reveal the system has relatively higher remanent polarization P _r (27.6 μC/cm²) and lower coercive field E _c (37.5 kV/cm).

SrTiO₃ thin film was successfully prepared on the functionalized organic self-assembled monolayers (SAMs) by the Liquid Phase Deposition (LPD) method. The as-prepared samples were characterized by X-ray diffraction (XRD), atomic force microscope (AFM), scanning electron microscopy (SEM) and metallographic microscope. Measurement of contact angle showed that the hydrophobe substrate was changed into hydrophile by UV irradiation. AFM photographs of octadecyl-trichloro-silane self-assembled monolayer (OTS-SAM) surface approved that UV irradiation did change the morphology of OTS monolayer and provided evidence for the conversion of hydrophilic characteristic. Photographs of Metallographic Microscope showed that OTS-SAM had an active effect on the deposition of SrTiO₃ thin film. XRD and SEM indicated that the thin film was of pure cubic phase SrTiO₃ and composed of nanosized grains with a size in the range of 100–500 nm. The formation mechanism of the SrTiO₃ film was proposed.

A series of nanometer TiO₂ photocatalysts co-doped respectively with rare earth Er³⁺-Ce³⁺ and La³⁺-Fe³⁺ were prepared by sol-gel method, and the photocatalytic activity under ultra-violet light was evaluated by photocatalytic degradation of methyl blue. The crystallographic forms, particles size, and morphology were characterized by XRD and TEM. The results showed that the optimum heat temperature of co-doped TiO₂ was 550 °C, and the co-doped TiO₂ kept anatase. The anatase crystal had the average size of 20 nm. The co-doping caused red-shift of the UV-Vis absorption spectra and enhanced the absorption of light. Compared with the spectrum of pure TiO₂ photocatalysts, the red-shift of Er³⁺-Ce³⁺ co-doping and La³⁺-Fe³⁺ co-doping catalysts was 53 nm and 34 nm, respectively. Optimal co-doping amount for Er³⁺-Ce³⁺ was n(Er³⁺): n(TiO₂)=0.1%, n(Ce³⁺): (TiO₂)= 0.05% and La³⁺-Fe³⁺ was n(La³⁺): n(TiO₂)=0.05%, n(Fe³⁺): (TiO₂)=0.5%. Under the condition the photocatalysis properties of the samples can be enhanced. It was found that the catalytic activity correlated well with the ratio. The degradation rate of methyl blue examined at two hour of the reaction was 92.37%, and the better photocatalysis properties than the non-doped TiO₂ were obtained. The co-doped photocatalyst on methyl blue degradation follows the apparent first-order kinetics.

The microstructure of a spray deposited intermetallic compound alloy of Ni-Al-Mo system (Ni₃Al-Mo intermetallic compound alloy) prepared by a spray atomization deposition was studied in detail by using optical metallography, XRD, DTA, SEM, TEM, HREM and computer simulation. The preform consists of uniform and equiaxial grains, ranging from 10–40 μm, with some microporosity. Besides the main phases of the matrix alloy γ′ and γ, Ni₂Mo and Ni₃Mo phases are also found within the γ network. A new Ni enriched phase in the γ phase was identified to have face-centered cubic structure with a lattice constant α=1.09 nm and space group Fm3m.

YAG (Y₃Al₅O₁₂) powder was prepared by co-precipitation method. To avoid pH values changing intensely during titration process, the NH₄HCO₃ solution with NH₄NO₃ was used as precipitant solution. The pH change of precipitant solution during titration process, compositions of precursor, phase formation process and morphology of the prepared powder were investigated by means of pH meter, FT-IR, XRD and TEM. The results show that the presence of NH₄NO₃ in NH₄HCO₃ solution is crucial to alleviate the pH change, lower the calcination temperature and meliorate the morphology of YAG powder. The mechanisms were studied in detail. The YAG phase can be obtained at a lower temperature of 900 °C. The obtained powder, composed of elliptical particles, showed a meliorated morphology.

Sol-gel process was adopted to prepare BiFeO₃ films. BiFeO₃ films were deposited on LaNiO₃ coated Si(100) substrates annealed at 500 and 550 °C, respectively. The X-ray diffraction results reveal that BiFeO₃ film has a rhombohedrally distorted perovskite structure with space group R3c. The film annealed at 500 °C has larger remnant polarization (P _r) of 35.3 µC/cm². For the film annealed at 550 °C, smaller remnant polarization of P _r=4.8 µC/cm² is observed for its low breakdown electric field. Lower leakage conduction is observed in the film annealed at 500 °C at low applied field.

The ultra-fine chromic oxide powder was prepared by a novel gas-solid reduction reaction. Na₂CrO₄ was firstly reduced with hydrogen at 400–600 °C. The obtained reduction products, mainly the mixture of NaCrO₂ and sodium hydroxide (NaOH), were converted into chromic oxide through hydrolysis followed by calcination. The obtained chromic oxide product was characterized by powder X-ray diffraction (XRD) and SEM. The results show that the hydrolysis process of sodium chromite is the key step and lower reduction temperature helps intensify the hydrolysis process.

Pore size distribution (PSD) curves of synthesized hollow silica spheres with ultrmicropores and small mesopores were obtained from calculations based on the BJH, KJS, SF, MP, NLDFT models and Prof. Zhu’s method. Comparisons indicate that Zhu’s method not only gives reasonable small mesopore size but also could be further extended to the ultramicropores region for the PSD evaluation.

A high-Mg₂Si content Al alloy was extruded by equal channel angular pressing (ECAP) for 8 passes at 250 °C and an ultrafine-grained structure with an average grain size of about 1.5 μm was achieved. The coarse skeleton-shaped Mg₂Si phase presenting in the as-cast alloy are significantly fragmented into fine rod-shaped as well as equiaxed particles mostly less than about 230 nm and become relatively dispersed. The tensile strength 192.8 MPa and the elongation up to 31.3% at ambient temperature are attained in the 8-pass ECAPed alloy versus 163.3 MPa and 9.1% in the as-cast alloy. High-temperature creep test at 250 °C reveals that the ECAPed sample exhibits a high elongation close to 100% at a relatively high creep rate 7.64×10⁻⁵ s⁻¹, compared to the elongation 56% at a low strain rate 1.74×10⁻⁷ s⁻¹ in the as-cast alloy.

Copper indium disulfide (CuInS₂) nano-particles were synthesized by solvothermal method at 150 °C using copper (I) chloride, indium (III) chloride, thiourea and ethanol as raw materials, and characterized by X-ray diffraction(XRD), field-emission scanning electron microscope (FESEM), and UV-Vis spectra. The effects of pH value on its micro-structures and optical properties were investigated. The results show that, with the pH value increasing, the particle size of the nano-crystalline CuInS₂ increases, and its band gap becomes narrower under alkaline condition. The band gaps of CuInS₂ nano-particles are from 1.52 eV to 1.93 eV, which makes them promising candidates as absorber materials for photovoltaic applications.

Styrene-isoprene-styrene (SIS) block copolymer was modified into epoxidized styrene-isoprene-styrene (ESIS) block copolymer with performic acid generated in situ from hydrogen peroxide and formic acid. The structure and property of ESIS were characterized by Fourier transform infrared (FT-IR) spectroscopy, gel permeation chromatography (GPC), thermogravimetric/differential thermogravimetric (TG/DTG), melt flow rate (MFR) and dynamic mechanical analysis (DMA), and the reaction mechanism in the process of epoxidation was analyzed. The results showed that C=C double bonds of 1,4-structure were more active than that of 3,4-structure in polyisoprene chains. With epoxidation reaction proceeding, the whole tendency of molecular weight increased and molecular weight distribution widened, and MFR firstly increased and latterly decreased. The heat resistance of ESIS was superior to that of SIS. When SIS was changed into ESIS with 15.3% of mass fraction of epoxide groups, T _g of polyisoprene chains increased from −45.3 °C to 10.9 °C. In the earlier period of epoxidation, some molecular chains ruptured and new substances with low molecular weight formed. However, in the latter period, crosslinking reaction between molecular chains which was initiated by epoxide groups or C=C double bonds occurred and crosslinked insoluble substances came into being.

Li₂O-Al₂O₃-SiO₂ glass prepared from traditional melting and cooling process was investigated. The surface characteristic of LAS glass was studied by simulating tin bath with different temperature and time, and the effect of surface tension/viscosity ratio on flatting time was analyzed. The results demonstrated that LAS glass can polish effectively when polishing at 1 300 for 8 °C min, and the optimum flatting and polishing temperature was 1 250–1 300 °C.

This paper describes an ethylene glycol (EG)-assisted approach to the ultralong Sb₂S₃ nanowires, formed by a simple hydrothermal reaction between SbCl₃ and Na₂S in the presence of distilled water. Transmission electron microscopy and scanning electron microscopy studies indicate that these Sb₂S₃ nanowires possess a diameter around 200 nm and length up to 100 μm. High-resolution transmission electron microscopy and selected area electron diffraction studies reveal that each Sb₂S₃ nanowire is a single-crystal along the [001] direction. The possible formation mechanism of the nanowires was discussed. The effects of volume ratio of ethylene glycol/water on the morphology of Sb₂S₃ nanowires were also investigated. Diffuse reflectance spectrum result shows that the final products have an apparent blue shift by quantum size effect.

Magnetic transitions and magnetotransport properties of polycrystalline Er_1−xGd _xMn₆Ge₆ (x=0.2−0.9) compounds were studied. The magnetic and resistivity properties were analyzed in an applied magnetic field up to 5 T. It is found that Er_1−xGd _xMn₆Ge₆ (x=0.2−0.9) compounds displays a transition from the antiferromagnetic state to the ferrimagnetic state for increasing Gd content. The Er_1−xGd _xMn₆Ge₆ with x=0.2 and 0.5 compounds order antiferromagnetically at 430 and 432 K, respectively. The Er_1−x Gd _xMn₆Ge₆ with x=0.8 and 0.9 compounds order ferrimagnetically at 462 and 471 K, respectively. The Er_1−xGd _xMn₆Ge₆ compounds undergo the second transitions below 71 K. The magnetoresistance curves of the Er_0.1Gd_0.9Mn₆Ge₆ compound in a field of 5 T are presented and the magnetoresistance effects are related to the metamagnetic transitions.

Effects of flame temperature and SiCl₄ concentration on the particle characteristics were studied. The flame temperature distributions were measured using modified sodium line-reversal technology. The particles were collected by quartz supports and were analyzed by scanning electron microscope (SEM) at different locations along the flame centerline. When the SiCl₄ concentration is 16 g/min, the particles first grow and then shrink with the flame temperature increasing. When the SiCl₄ concentration is 26 g/min, the flame temperature has little influence on the particle characteristics along the flame and many large spherical particles exist all the way.

The simulation of nanoindentation into single nickel crystal is performed by using quasi continuum method. The strain energy-displacement and load-displacement curves are presented to study the mechanical behavior of the dislocation nucleation. The characteristics of the stacking fault and dislocation nucleation are determined by calculating the centro-symmetry parameters and analyzing the displacement field of the atoms beneath the indenter. The structure of the stacking fault and the characteristics of dislocation obtained in the simulation by quasicontinuum method are reproduced in the simulation by molecular dynamics.

Nanocrystalline Ni_1−xZn _xFe₂O₄ ferrites with 0⩽x⩽1 were successfully prepared by a spraying-coprecipitation method. The microstructure was investigated by using XRD and TEM. Magnetic properties were measured with vibrating sample magnetometer (VSM) at room temperature. The results show that the grain size of nanocrystalline Ni_1−xZn _xFe₂O₄ ferrite calcined at 600 °C for 1.5 h is about 30 nm. Lattice parameter and specific saturation magnetization M _s of nanocrystalline Ni_1−xZn _xFe₂O₄ ferrite increase with the Zn²⁺ ions content at room temperature, and maximum M _s is 66.8 A · m² · kg⁻¹ as the Zn²⁺ ions content is around 0.5, and coercivity H _c of the nanocrystalline Ni_1−xZn _xFe₂O₄ ferrite decreases with Zn²⁺ ions content.

In-situ characterization of non-aqueous nano-dispersion systems(NANDS) by freeze-etching transmission electron microscope (FETEM) was reported. To improve just-for-once successive rate of specimen preparation and get good characterization results, an improving specimen preparation method of freezing etching was developed. Size, distribution and morphology of NANDS were directly visualized. Some information of particle dispersion feature and particle density can also be obtained. Reproductivity of the FETEM characterization is excellent. Comparing with laser scattering method, which is liable to give positive error especially for small size particle anchoring disperser, FETEM characterization can give more accurate measurement of particle size. Moreover, FETEM can give dispersion feature of nanoparticle in non-aqueous medium.

W-25Cu alloys were microwave sintered in a 2.45 GHz multimode applicator. The densification, microstructure and their dependence on sintering mode and Fe addition were investigated in detail. Owing to the volumetric heating intrinsic in microwave processing, a microstructure with larger W grain size in center regions was observed as against larger grain size in edge regions for conventional sintering. Microwave sintering demonstrates its intrinsic advantages such as rapid heating rate, densification enhancement and microstructural homogeneity; but it undesirably promotes W grain growth. Under microwave sintering, the role of Fe addition on compact consolidation is not so substantial as under conventional sintering. Moreover Fe degrades the microstructural quality, generating worse uniformity and coarser W grains.

A montmorillonite inorgano-intercalation compound(MIIC) was synthesized by using a purified Na-exchanged bentonite (PNaB) as a matrix and Al-pillaring ion as an intercalating reagent under microwave irradiation. The synthesized products were characterized by X-ray diffraction (XRD), ²⁷Al magic angle sample-spinning nuclear magnetic resonance (²⁷Al MAS NMR), specific surface area (BET) measurement, and adsorption density determination. The results show that, at 5% solid (PNaB) concentration and 7 minutes irradiation in a 130 W microwave oven, the basal spacing d ₍₀₀₁₎ of the synthesized MIIC increases to 1.740 nm from the original 1.218 nm of PNaB. The MIIC has much higher adsorptive densities to F⁻ and Cr⁶⁺ from aqueous solution than the PNaB. The adsorption isotherm of F⁻ on the MIIC follows the Freundlich equation, and the increased adsorption is mainly due to the porous structure of the MIIC which created larger adsorption surfaces. The adsorption isotherm of Cr⁶⁺ on MIIC follows the Langmuir equation and the adsorption is mainly monolayer as a result of chemisorptions.

The semi-continuous casting of ZK60 magnesium alloy under different middle frequency electromagnetic field conditions was examined. Effects of middle frequency electromagnetic field on microstructure, precipitations and tensile properties are investigated. The results show that the microstructures of ZK60 magnesium alloy are refined and distribution uniformity of precipitations is observed after applying the middle frequency electromagnetic field. And the tensile properties of the billets produced by middle frequency electromagnetic field are increased.

The bearing capacity of FRP confined concrete-filled steel tubular (FRP-CFST) columns under axial compression was investigated. This new type of composite column is a concrete-filled steel tube (CFST) confined with fiber-reinforced polymer (FRP) wraps. Totally 11 short column specimens were tested to failure under axial compression. The influences of the type and quantity of FRP, the thickness of steel tube and the concrete strength were studied. It was found that the bearing capacity of short FRP-CFST column was much higher than that of comparable CFST column. Furthermore, the formulas for calculating the bearing capacity of the FRP-CFST columns are proposed. The analytical calculated results agree well with the experimental results.

CuS pineal microspheres congregated from interleaving nanoflakes with thickness of 40 to 200 nm were synthesized by a pyridine-solvothermal process via the reaction between cupric chloride (CuCl₂·2H₂O) and thioacetamide (TAA, CH₃CSNH₂). The products were characterized by X-ray diffraction and scanning electron microscopy. UV-Vis absorption spectrum, excitation and photoluminescence spectra of CuS pineal microspheres were obtained at room temperature to investigate their optical properties. A possible growth mechanism on the formation of CuS pineal microspheres is proposed. The factors influencing the evolution of morphologies of CuS crystals including the dosage of the reactants, surfactant, and sulphur-source were also analyzed.

To obtain the compatible material of high hardness and high toughness, Hadfield steel matrix composites, reinforced by high-Cr cast iron bars made of flux-cored welding wires, which were inserted into the Hadfield steel melt, were investigated. The mechanical properties of three materials, i e, composites for as-cast and quenching-water condition, as well as Hadfield steel, were compared. The results show that the alloy powder inside flux-cored welding wires can be melted by the heat capacity of Hadfield steel melt and solidify into high-Cr cast iron bars. The impact toughness of the composite for quenching-water condition is higher than that of the composite for as-cast condition and is lower than that of the Hadfield steel, but it can still meet the requirements of hardness and toughness in industrial application. Regardless of load variation, composite for quenching-water condition shows better wear resistance than those of the composite for as-cast condition and Hadfield steel. The modified fracture toughness and wear resistance of composites are attributed to not only the combining actions of Hadfield steel matrix and high-Cr cast iron bars, but also the effect of heat treatment.

The adhesion wear of cemented carbide tool when machining GH907 was studied with white light interferometer, infrared imaging, and SEM-EDS. The adhesion wear morphology, wear mechanism and the wear rule of adhesion were analyzed, and the effect of different cutting time and different cutting speed on adhesive wear were analyzed. The conclusion will provide useful references for the optimization of cutting parameters and the improvement of the tool life.

Nano-hydroxyapatite reinforced poly(vinyl alcohol) gel (nano-HA/PVA gel) composites has been proposed as a promising biomaterial, especially used as an articular cartilage repair biomaterial. In this paper, nano-HA/PVA gel composite was prepared by in situ synthesis method and incorporation with freeze-thaw cycle process. The microstructure and morphology were investigated by X-ray diffraction, TEM, SEM and FTIR. The results showed that the size of HA particles synthesized in PVA solution was on the nanometer scale. Both the size and crystallinity of HA particles synthesized in PVA solution decreased compared with that of HA synthesized in distilled water. The nano-HA particles were distributed in PVA matrix uniformly due to the effect of PVA solution as a dispersant while low content of HA particles in the composites. On the contrary, with high content of nano-HA particles in the composites, the particles tended to aggregate. The result of FT-IR analysis indicated that the chemical bond between nano-HA particles and PVA matrix existed. The conformation and degree of tacticity of PVA molecule changed because of the addition of HA particles. Furthermore, the interfacial strength of the composites was improved due to the interaction between nano-HA particle and PVA matrix and this was beneficial to improving the mechanical properties of the composites.

The thermal degradation of synthetic waterborne polyurethane (PU) based on toluenediisocyanate (TDI) was investigated by pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) and thermogravimetry (TG). The degradation profiles of cast films obtained from dispersions were evaluated. More than 20 characteristic volatile pyrolyzates reflecting the structure and pyrolysis mechanisms of the polymer have been identified by on-line MS. In helium atmosphere, the synthesized products of polyurethane were pyrolyzed at 350, 450, 550, 650 and 750 °C respectively, and the thermal decomposition products were analyzed on line using GC/MS. The product analysis reveals that the pyrolyzates distribution of the polyurethane depends strongly on the pyrolysis temperature. Based on the Py-GC/MS data, the thermal degradation mechanism of the polyurethane is discussed.

A novel nano-hydroxyapatite (HA)/konjac glucomannan composite scaffold with high porosity was developed by blending nano-HA particles with konjac glucomannan in alkaline solution. The scanning electron microscopy, porosity measurement, X-ray diffraction(XRD), and Fourier transformed infrared(FTIR) spectroscopy were used to analyze the physical and chemical properties of the composite scaffolds. The pure konjac glucomannan scaffolds and composite scaffolds were similar in their macroscopic morphology, however, the microscopic morphology on porewall surfaces was quite different. The diffraction patterns of XRD revealed the presence of konjac glucomannan and HA in the composite scaffolds. In addition, the results of FTIR also showed the existence of the functional group of HA. These results reveal that the newly developed nano-HA/konjac glucomannan composite scaffold may serve as a good three-dimensional substrate in bone tissue engineering.

Three novel copolymers, poly[1-(4-(benzothiazole-2-thio-alkyloxy)-biphenyl-4′-oxy)2.3-epoxypropane]s, were synthesized by the reaction of polyepichlorohydrin with obtained monomers, 4-(benzothiazole-2-thio-alkyloxy)biphenyl-4′-ols, in which the number of methylene unit in substitution group of biphenyl group was 2, 4, 6, respectively. The structures of obtained compounds were confirmed by elemental analysis and ¹H NMR. The decomposition temperatures of copolymers were near 340 °C. Differential scanning calorimetry (DSC) measurement and polarized optical microscopy (POM) observation showed the resulting copolymers did not exhibit thermotropic liquid crystalline mesomophism and belonged to semi-crystalline substance.

The PAL was synthesized with BA, MMA and some monomers containing carboxyl groups (for example, acrylic acid (AA) and methacrylic acid (MAA)) as co-monomers by semi-continuous seeded emulsion polymerization technique. The influences of alkalinization temperature, the feeding manner of AA or MAA on the particles size Rheological properties and carboxyl distribution of the latex were discussed, and the rheological mechanism was analyzed. The experimental results show that the PAL system has preferable viscosity and particle size when the alkalinization temperature is 50 °C. Different distribution of carboxyl group in the particles and different resultant rheological properties are obtained by different feeding manner of AA or MAA into the system. The TEM images show that the particle is a smooth globe with carboxyl group concentrating on the surface and stabilized with electric double layer and nonionic adsorbed layer. The concentration of carboxyl functional group on the surface of particles can be achieved by the specific polymerization technique. The rheologyical properties are determined by accretion of particle volume and variation of the two phase volume ratio resulted from the carboxyl group spreading layer.

The breakthrough curves of benzene and water on modified activated carbons (ACs) were investigated. Temperature-programmed desorption (TPD) experiments were conducted to measure the TPD curves of benzene and water on modified and unmodified ACs and to estimate the activation energy for the desorption of benzene on the modified ACs. Starting with unmodified ACs, two modified ACs were prepared by using two different types of silane, designated by KH560 and 1706. The results showed that the activation energy for the desorption of benzene on KH560/AC and 1706/AC was higher than that on unmodified AC. In addition, the activation energy for the desorption of water on KH560/AC and 1706/AC was lower than that on unmodified AC. The breakthrough curves of benzene obtained from the experimental observations under different humidity conditions were compared with the results of the TPD experiments. The results show that the modified ACs are less affected by water, whereas the unmodified ACs are more affected by water, indicating that surface modification by organosilane compounds can improve the adsorption of benzene on the activated carbo, which weakens the adsorption of water.

The relationship between autogenous deformation and internal relative humidity (IRH) of high-strength concrete and high-strength expansive concrete were investigated. The experimental results indicate that, there exists a good linear relationship between autogenous shrinkage and IRH of high-strength concrete but a nonlinear relationship between autogenous deformation and IRH of high-strength expansive concrete with expansive agent. The new autogenous deformation curve can be obtained by transforming the autogenous deformation data of high-strength expansive concrete, and there exists linear relationship between the autogenous deformation and IRH. The concept of “critical internal relative humidity” was proposed, which is defined as the value of IRH when autogenous deformation is zero, to effectively reflect the autogenous deformation characteristic of expansive concrete.

Mechanical behaviors of UHTCC after freezing and thawing were investigated, and compared with those of steel fiber reinforced concrete (SFRC), air-entrained concrete (AEC) and ordinary concrete (OC). Four point bending tests had been applied after different freezing-thawing cycles (0, 50, 100, 150, 200 and 300 cycles, respectively). The results showed that residual flexural strength of UHTCC after 300 freezing-thawing cycles was 10.62 MPa (70% of no freezing thawing ones), while 1.58 MPa (17% of no freezing thawing ones) for SFRC. Flexural toughness of UHTCC decreased by 17%, while 70% for SFRC comparatively. It has been demonstrated experimentally that UHTCC without any air-entraining agent could resist freezing-thawing and retain its high toughness characteristic in cold environment. Consequently, UHTCC could be put into practice for new-built or retrofit of infrastructures in cold regions.

To compare the results obtained under both natural and accelerated environments, the pH values of carbonated concrete were measured, the variation of pH values was determined, and the variations of Ca(OH)₂ and CaCO₃ contents in the carbonated concrete under natural condition and high CO₂ concentration accelerated climate environments were determined by microcosmic test methods such as DTA and X-ray diffraction. The experimental results showed that the overall variation trend of pH values and phase component of carbonation layer of concrete under accelerated climate environments with high CO₂ concentrations were the same as those under natural conditions. Therefore, the carbonation processes of concrete were considered consistent under both conditions. However there was a difference in the length of semi-carbonation zones. The one measured under high CO₂ concentration accelerated climate environments was shorter than that under natural condition. Experimental investigation showed that it was caused by the differences in climate condition (temperature and relative humidity) as well as the properties of the concrete. The concentration of CO₂ and the duration of the carbonation process have no effect on the length of semi-carbonation zone. Thus, it is acceptable to simulate the natural condition by applying the high CO₂ concentration artificial accelerated carbonation technique for the purpose of the study of carbonation process of concrete.

The steel bars with good electrical conductivity were used as two kinds of electrodes in the making of carbon fiber (CF) electrically conductive concrete for heating. The results of the pertinent experiments illustrate the design is viable. The change in electrical resistivity over three years’ hydration time was studied when steel bars were used as lateral face electrodes and top bottom surface electrodes respectively. The temperature rise test was conducted to verify the heating properties of two kinds of concrete. Not only the study can reduce the CF volume content of electrically conductive concrete for heating to 0.58% or 0.36% according to different design, but also it will enhance the carrying capacity of the concrete roadway for heating.

Zn_1−xCo _xO diluted magnetic semiconductor bulks were prepared by hot pressing. Mixed powders of pure ZnO and CoO were compacted under pressure of 10 MPa at the temperature of 1 073 K. Then the samples were annealed in vacuum at the temperature from 673 K to 873 K for 10 h. The crystal structure and magnetic properties of Zn_1−xCo _xO bulks have been investigated by X-ray diffraction (XRD) and vibrating sample magnetometer (VSM). X-ray photoelectron spectroscopy (XPS) was used to study chemical valence of zinc and cobalt in the samples. The results showed that Zn_1−xCo _xO samples had c-axis oriented wurtzite symmetry, neither cobalt or cobalt oxide phase was found in the samples if x was less than 0.15. Zn and Co existed in Zn_0.9Co_0.1O sample in Zn²⁺ and Co²⁺ states. The results of VSM experiment proved the room temperature ferromagnetic properties (RTFP) of Co-doped ZnO samples. The saturation magnetization and the coercivity of Zn_0.9Co_0.1O sample, observed in the M-H curve, were about 0.20 emu/g and 200 Oe, respectively.

For a better understanding of the strains and stresses, numerical simulation was conducted by using ANSYS under the assumption of absolute bond between the steel and concrete. The results show that the stresses and strains in such concrete and steel rings are uneven; the curves of strains and stresses change gradually around the interface. To ease numerical computation, the mechanical system was simplified under the assumptions of synchronous deformation and uniform strains and stresses. The results of the numerical simulation and simplified stress calculation can match almost perfectly. It means that the simplified mechanical model can be used in stress and visco-elastic behavior quantification.

By using the falling weight deflectometer (FWD), the dynamic loading tests on different thickness of asphalt mixture pavement in different temperature were performed. The experimental results show that the effects of temperature on dynamic properties of asphalt mixture are significant, and the thickness of asphalt mixture is also another important influence factor. The comparisons indicate that effect of temperature on the behaviors of dynamic loading properties and static loading properties of asphalt mixture were quite different.

A novel methodology for the formulation design of the multi-component cement additive for the low early strength blend cement was presented by using engineering statistics. Components of cement additive such as triethanolamine, chloride, saccharide and a kind of divalent alcohol were simultaneously tested according to the arrangement of response surface methodology. Mathematical models were established to express the quantitative relationship between the chemical components of cement additive and the compressive strength of treated blend cement. The effectiveness and the possible interactions of these four chemicals contributing to the strength development of blend cement were further explored by the pareto chart and the contour plot. Finally according the performance analysis of four chemicals, the optimized formulations were brought forward and were validated in practical trials by Turkey’s multiple comparison.