Pr _x(Co₄₀Ag₆₀)_100−x (x=0, 0.5, 1, 1.5, 2, 3) granular films have been prepared by DC magneto controlled sputtering method. The XRD data indicated that Pr element favors the (111) plane preferential orientation. Magnetic measurements indicate that the average size of magnetic particles decreases as Pr content increases. For relatively low addition of Pr to CoAg granular films, Pr element can enhance GMR value and a peak value of about −14.3% is obtained at x=1.

A novel UV-curable prepolymer hexanediol diglycidyl ether diacrylate (HDGEA) was synthesized by utilizing hexanediol diglycidyl ether (HDGE) and acrylic acid (AA) as starting materials, N, N-dimethylbenzylamine as catalyst and p-hydroxyanisole as inhibitor. The optimal synthetic conditions were that the concentration of N, N-dimethylbenzylamine was 0.80 wt% of reactants, the concentration of p-hydroxyanisole was 0.3 wt% of reactants, the reaction temperature was 90–110 °C, and the molar ratio of HDGE to AA was 1: 2.2. Meanwhile, 1-hydroxycyclohexyl phenyl ketone of a UV-curing initiator was added to the synthesized HDGEA to prepare a kind of UV-curing coating. The mechanical properties of the UV-cured films were determined, giving 31.87 MPa of tensile strength, 871.88 MPa of Young’s modulus and 6.77% of elongation at tear.

Bamboo sawdust was used as the precursor for the multipurpose use of waste. Offgases released during the activation process of bamboo by KOH were investigated quantitatively and qualitatively by a gas analyzer. TG/DTG curves during the pyrolysis process with different impregnation weight ratios (KOH to bamboo) were obtained by a thermogravimetric analyzer. Pyrolysis mechanism of bamboo was proposed. The results showed that the offgases were composed of CO, NO, SO₂ and hydrocarbon with the concentration of 1 372, 37, 86, 215 mg/L, respectively. Thermogravimetric analysis indicated that the pyrolytic process mainly experienced two steps. The first was the low temperature activation step (lower than 300°C), which was the pre-activation and induction period. The second was the high temperature activation step(higher than 550°C), which was a radial activation followed by pore production. The second process was the key to control the pore distribution of the final product.

Liquid ball-milling dispersant method was used to prepare the ZrO₂-doped carbon laminations from mesocarbon microbeads(MCMBs). After sintering at 1 300 °C in nitrogen atmosphere, the effect of ZrO₂ concentration on sintering behavior, electric conductivity as well as bending strength of the carbon laminations was investigated in detail. The results showed that the volumetric shrinkage rate of the carbon laminations decreased from 38.2% to 30.9% when the ZrO₂ concentration in raw materials varied from 0 to 16 wt%. Compared with undoped carbon lamination, the samples had high-electric conductivity and excellent bending strength in all cases. The electric conductivity achieved the maximum value of 225 S/cm, and the bending strength of the carbon lamination was 119.24 MPa for a concentration of 8 wt% ZrO₂ in raw materials. In addition, the electric conductivity and bending strength reducing were observed when the ZrO₂ concentration was higher than 8 wt%. The catalytic effect on graphitization for the carbon laminations was the most effective when the ZrO₂ concentration was set at 8 wt% in raw materials.

Crystals of semiconductor ZnO were fabricated by means of solid-vapor growth method—carbon thermal reduction. Powder X-ray diffraction and field emission scanning electron microscope were used to characterize the phase and morphology of the samples. The results showed that the samples were wurtzite ZnO crystals and anisotropy of crystal growth relied on reaction temperature in solid-vapor process. The crystals synthesized at different temperatures were of short column-like shape, flat top hexagon pyramidal-like shape and polyhedron shape. The growth mechanisms of the above three kinds of crystal were consistent with the theory of growth basic structural unit of negative ion coordination polyhedron. At first, Zn²⁺ and four O²⁻ form [Zn-O₄]⁶⁻ coordination tetrahedron at any temperature. Then, tetrahedrons stack in different ways into different morphology crystal at different temperatures.

Na-doped ZnO thin films were deposited on the glass substrates using sol-gel method. The effect of Na concentrations on the structural and optical properties of ZnO films was studied. As Na concentration increases from 0.0 at% to 16.0 at%, preferential c-axis orientation becomes more and more obvious, and the intensity of the diffraction peaks from (103) increases. The optical band gap E _g value increases from 3.261 to 3.286 eV first and then decreases as Na concentration increases from 0.0 to 2.0 at% and then beyond 2.0 at%. The intensity of all the emissions increases with increasing Na concentration and the origins of the violet emission (wavelength in the 400–407 nm) and the blue emission (wavelength at 473 nm) were discussed in detail.

Carbon nanotube encapsulated nickel nanorods were catalytic grown via pyrolysis of oil on a bulk nickel wire substrate. X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy and Raman spectroscopy were employed to characterize the as-prepared sample. The results show that, carbon nanotubes possess several microns in length, the filled metallic nickel nanorods with a uniform diameter of 35 nm were tightly encapsulated by the carbon capsules. The detailed formation mechanism for the carbon nanotubes encapsulated nickel nanorods were discussed briefly.

Manganese dioxide was synthesized by electrodeposition method with Mn (CH₃COO)₂ · 4H₂O as a raw material. La(NO₃)₃ · 6H₂O was doped in electroyte during the preparing process to improve the performance of MnO₂ electrodes. The micrographs, crystal structure and element content of electrodes were analyzed by SEM, XRD and atomic absorption spectroscopy, respectively. It is found that the La content ratio in the dioxide can be easily controlled by adjusting the composition of the plating solution. Appropriate amount of doped La can increase the surface area of Mn/La materials, resulting in the supercapacitive behavior enhancement. Electrochemical tests show that the specific capacitance is significantely increased from 198.72 F · g⁻¹ to 276.60 F · g⁻¹ by La-doping.

Using the polymerizable hydrophobic styrene monomer as the dispersion medium and the traditional nonionic surfactant OP-10 as emulsifier, stable silver nanoparticles of narrow size distribution were prepared by a reverse (w/o) microemulsion method. The powder X-ray diffraction (XRD) pattern indicated that the obtained silver nanoparticles were of face-centered cubic structure. The results of the transmission electron microscopy (TEM) show that the final silver nanoparticles are of spherical structure with an average diameter of 15.2 nm and of a Gaussian distribution. The internal high-ordered structure of silver nanoparticles was characterized by the field-emission high-resolution transmission electron microscopy (FEHRTEM), indicating that the silver is monocrystalline and it has only one nucleation site during the formation process of a nanoparticle. The time-resolved UV-visible absorption spectra was used to monitor the process of the reaction in situ. The results show that the concentration of silver nanoparticles increases but the size changes little and the morphology transforms from obvious ellipsoidal shape to nearly spherical shape during the process. The experimental results indicate that the droplets’ dynamic exchange which is closely related to the nature of surfactant film is the control factor of the kinetics. The dynamic exchange mechanism of silver nanoparticle formation is proposed to involve continual encounter of two separate droplets forming transient fused dimer in which the chemical reaction occurs followed by re-separation without combination. Attributed to the dual role of surfactant in the nanoparticle formation, tailored nanoparticles can be successfully synthesized in control in the premise of a certain stability of reverse microemulsion.

Rejuvenator diffusing into aged bitumen was evaluated by determining penetration and chemical components of aged bitumen with rejuvenator coat before and after diffusing experiment. Effects of temperature, time and viscosity of rejuvenator on the diffusing ability of rejuvenator into aged bitumen were investigated. Results indicated that the diffusing ability of rejuvenator into aged bitumen could be enhanced with the increasing of temperature and time, however, the diffusing of rejuvenator into aged bitumen would be restricted due to the volatilization of light component and aging of rejuvenator under high temperature (over 170 °C). Rejuvenator with low viscosity diffused into aged bitumen more easily.

Porous ZnO films were prepared by electrodeposition method in zinc nitrate aqueous solution using ITO glass covered with polystyrene sphere (PS) colloidal crystal arrays as substrates. The preparation procedure includes two parts: deposition of ZnO in the interstices of the colloidal crystals and subsequent removal of the PS templates. The influences of deposition potential and temperature on the ZnO films were investigated. The ordered, uniform porous ZnO films with optical transmittance of approximately 63.6% at 600 nm could be obtained when the deposition potential and temperature were −1.1 V and 70 °C, respectively. The optical band gap energy increased along with the absolute deposition potential and temperature, ranging from 3.33 to 3.43 eV and from 3.35 to 3.42 eV, respectively.

Aluminium doped ZnO thin films(ZnO:Al) were deposited on transparent polymer substrates at room temperature by rf magnetron sputtering method from a ZnO target with Al₂O₃ of 2.0 wt%. Argon gas pressure varied from 0.5 Pa to 2.5 Pa with radio frequency power of 120 W. XRD results showed that all the ZnO:Al films had a polycrystalline hexagonal structure and a (002) preferred orientation with the c-axis perpendicular to the substrate. The grain sizes of the films were 6.3–14.8 nm.SEM images indicated the ZnO:Al film with low Argon gas pressure was denser and the deposition rate of the films depended strongly on the Argon gas pressure, increasing firstly and then decreasing with increasing the pressure. The highest deposition rate was 5.2 nm/min at 1 Pa. The optical transmittance of the ZnO:Al films increased and the blue shift of the absorption edge appeared when the Argon gas pressure increased. The highest transmittance of obtained ZnO:Al films at 2.5 Pa was about 85% in the visible region. The electrical properties of the films were worsened with the increase of the Argon gas power from 1 Pa to 2.5 Pa. The resistivity of obtained film at 1.0 Pa was 2.79 ×10⁻² Ω·cm.

ZrO₂/Ni nanocomposite was produced by pulse electrodeposition and its superplastic properties were investigated by the tensile and bulging tests. The as-deposited nickel matrix has a narrow grain size distribution with a mean grain size of 45 nm. A maximum elongation of 605% was observed at 723 K and a strain rate of 1.67×10⁻³s⁻¹ by tensile test. Superplastic bulging tests were subsequently performed using dies with diameters of 1 mm and 5 mm respectively based on the optimal superplastic forming temperature. The effects of forming temperature and gas pressure on bulging process were experimentally investigated. The results indicated that ZrO₂/Ni nanocomposite samples can be readily bulged at 723 K with H/d value (defined as dome apex height over the die diameter) larger than 0.5, indicating that the nanocomposite has good bulging ability. SEM and TEM were used to examine the microstructure of the as-deposited and bulged samples. The observations showed that significant grain coarsening occurs during superplastic bulging, and the microstructure is found to depend on the forming temperature.

A series of glasses with high Bi₂O₃ content of Bi₂O₃-B₂O₃-WO₃ ternary system were chosen and prepared. Their densities and linear refractive indices increase with increasing WO₃ content. The optical band gaps E _opt of glasses obtained from ultraviolet absorption edges decreases with increase of WO₃ content. Z-scan technique was carried out to investigate the third-order nonlinear optical properties of the glasses. It is found that the nonlinear refraction γ increases with decreasing the optical band gap E _opt, since an increase of WO₃ content can promote the non-bridging oxygen ion content, and the highest γ value of samples is 1.173×10⁻¹⁴ cm²/W. The results show that these glasses are potential materials in the application of third-order nonlinear optics field.

Multi-walled carbon nanotube (MWCNT)/TiO₂/C₆₀ composite catalysts were prepared by hydrothermal method. TiO₂ was deposited on the MWCNT surface. Their photocatalytic activities for degradation of Rhodamine B dye were studied. X-ray diffraction, field emission transmission electron microscopy, ultraviolet-visible light absorption spectrum and photoluminescence spectrum were carried out to characterize the composite catalysts. The results indicated that MWCNTs and C₆₀ could greatly enhance the photocatalytic activity of TiO₂.

An arachidic acid/poly (3, 4-ethylene dioxythiophene) (AA/PEDOT) multilayer Langmuir-Blodgett (LB) film was prepared by a modified LB film method. The theories were utilized to explain the effects between HCl molecule and LB film. The gas sensitivity mechanism of poly (3, 4-ethylene dioxythiophene) (PEDOT) multilayer film can be explained by the charge transfer between p system of PEDOT and oxidization HCl system. The gas sensitivity of PEDOT LB film deposited interdigital electrode to HCl was tested. The results showed that film thickness, treating temperature, deposition speed had different influence on film gas sensitivity. The AA/PEDOT film deposited device exhibited nonlinear behavior to HCl gas at lower concentration (20–60 ppm) and linear response behavior at higher gas concentration was observed. The time of the compound LB film of the AA/PEDOT responding to the 30 ppm HCl gas is about 20 seconds, which is far quicker than the time of the film to the PEDOT-PRESS film(about 80 seconds). It is not higher film press to better film. When the film press attains 45 mNs/m, the sensitivity of the AA/PEDOT film on the contrary descends.

A novel surface modification method was proposed to improve the tribological property of Si. Multilayers were grown on Si(100) substrate by self-assembling monolayer (SAMs) method and filtered catholic vacuum arc (FCVA) technique. The film composition and structure were characterized by using x-ray photoelectron spectroscope (XPS) and Raman spectroscopy (Raman). Surface morphology and the roughness were also analyzed by an atomic force microscope (AFM) and a scanning electron microscopy (SEM). The frictional behaviors of the films were evaluated by a UMT tester. Results showed that elastomeric nanocomposite monolayer prepared by SAM was uniformly distributed and isotropy, and the diamond-like carbon (DLC) film was successfully deposited by the FCVA technique. The friction coefficients of the prepared samples were in the range of 0.108–0.188. Furthermore, the friction coefficient slightly increased but the surface quality of the wear trace was improved after adding the copolymer elastomeric macromolecules SEBS on aminopropyl-triethoxysilane (APS) layer due to the inherent long chain of SEBS which abated the immediate impulsion at the interface and changed the kinetic energy into elastic potential energy, and stored it in SEBS.

An alternative polymeric surfactant P(M3/St) was synthesized by solution polymerization of maleamic acid as hydrophilic monomer and styrene as hydrophobic monomer. Some factors that affect the yield and properties of the polymeric surfactant were investigated systemically. The surface tension of the polymeric surfactant reaches 37–38 mN/m. It is proved that the polymeric surfactant shows very good surface activity and emulsifying ability. The TG analysis shows that the temperature of the thermal degradation can reach 314.4 °C. It will be used as a new type of polymeric surfactant.

An obvious antiplasticizing effect has been observed in PVC with small amount of MOCA, 3,3′-dichloro-4,4′-diamino-diphenylmethane. PVC-MOCA interaction and crystallization behavior of PVC/MOCA blends were investigated in detail to explain the mechanism of antiplasticization on the basis of a series of techniques including DMA, FTIR, and DSC. The results of mechanical properties tests show that the tensile strength of PVC with 5 phr of MOCA reaches a maximum value, 69.5 Mpa, which is about 23 % higher than that of pure PVC. The rise in tensile strength was attributed to an antiplasticizing effect of MOCA on PVC as confirmed by DMA measurements. The evidences from FTIR reveal that a strong hydrogen-bonding interaction takes place between the nitrogen atom of -NH₂ groups in MOCA and the methine proton of PVC repeat units. The results of DSC analysis indicate that crystallization behavior of MOCA is suppressed completely and the crystallinity of PVC decreases with the increase of MOCA amount.

Full factorial design of experiments was developed in order to investigate the effects of jet pressure, abrasive mixing rate, cutting feed, and plate thickness upon three response variables, surface finish of cutting wear zone, percentage proportion of striation free area, and maximum width of cut. The set of sixteen experiments was performed on each of the following two ductile materials: AISI 4340 (high strength low alloy steel, hardened to 49HRc) and Aluminum 2219. Analysis of Variance (ANOVA) was performed on experimental data in order to determine the significance of effects of different parameters on the performance measures. It was found that cutting feed and thickness were highly influential parameters, while abrasive mixing rate is influential upon surface roughness only. Strong interaction was found between jet pressure and workpiece material. Multi-criteria numerical optimization was performed in order to simultaneously maximize/minimize different combinations of performance measures.

The hydrogen content in aluminum melts at different temperature was detected. The structure in aluminum melts was investigated by molecular dynamics simulation. The first peak position of pair correlation function, atomic coordination number and viscosity of aluminum melts were calculated and they changed abnormally in the same temperature range. The mechanism of hydrogen absorption has been discussed. From molecular dynamics calculations, the interdependence between melt structural properties and hydrogen absorption were obtained.

Local atomic structures of an amorphous Mg₆₅Cu₂₅Gd₁₀ alloy and the structural changes by thermal annealing have been studied by extended X-ray absorption fine structure (EXAFS). The correlation between structural changes and mechanical properties for the Mg₆₅Cu₂₅Gd₁₀ alloy has also been discussed. Results showed that Cu atoms around Gd in Mg₆₅Cu₂₅Gd₁₀ lost rapidly during annealing, resulting in the segregation of Cu atoms. The coordination number NGd-Mg of Mg₆₅Cu₂₅Gd₁₀ annealed at 373 K first diminished and then augmented with the increase of annealing time. The formation of polyhedral short-range order unit with coordination number of nearly 12 around Gd atoms is in favor of the improvement of mechanical properties. The chemical short-range order, not topological short-range order in the amorphous Mg₆₅Cu₂₅Gd₁₀ alloy had obvious changes during annealing.

The effects of lanthanum-praseodymium-cerium mischmetal (LPC) on the microstructure and mechanical properties of Mg-Al alloy were investigated. With the addition of LPC, an additional rod-like Al₁₁La₃ phase was deposited in the alloy. LPC greatly improves the tensile strength of cast Mg-Al alloys but negatively affects the elongation of cast alloys above 473 K. Cast alloys are strengthened by both precipitation strengthening and dispersion strengthening at ambient temperature. When the temperature exceeds 473 K, only the dispersion operates as a strengthening mechanism.

An approach named “pore structure collapsed replication route” has been developed to prepare mesoporous WC materials with a high surface area (105 m²/g) and crystallized framework at a temperature as low as 700 °C. The XRD, TEM, EDS, and BET characterizations were conducted to analyze the effects of the synthesis parameters and the template types on the structure of mesoporous WC. The compaction on the templates is the key to form mesoporous structure of WC while the templates help to control the size of crystalline. At a content of 7 wt% for the precursor of WC, the mesoporous WC could be formed with well ordered structure.

The 3, 5, 20 layer clad plate from austenitic stainless steel, pure aluminum and aluminum alloy sheets were fabricated in different ways. The stretch and interface properties were measured. The result shows that 20 layer clad plate is better than the others. Well-bonded clad plate was successfully obtained in the following procedure: Basic clad sheet from 18 layer Al1060/Al3003 sheets was firstly obtained with an initial rolling reduction of 44% at 450 °C, followed by annealing at 300 °C, and then with reduction of 50% at 550 °C from STS304 on each side. The best 20 layer clad plate was of 129 MPa bonding strength and 225 MPa stretch strength.

The measurement of thermal cycle curves of a high-strength low-alloy steel (HSLA) subjected twin-wire submerged arc welding (SAW) was introduced. The thermal simulation test was performed by using the obtained curves. The impact toughness at −50 °C temperature of the simulated samples was also tested. OM, SEM and TEM of the heat-affected zone (HAZ) of some simulation specimens were investigated. The results showed that the HSLA endured the twin-wire welding thermal cycle, generally, the low-temperature toughness values of each part of HAZ was lower than that of the parent materials, and the microstructure of coarse-grained zone(CGHAZ) mainly made up of granular bainite is the reason of the toughness serious deterioration. Coarse grain, grain boundary carbide extract and M-A island with large size and irregular polygon, along the grain boundary distribution, are the reasons for the toughness deterioration of CGHAZ. The research also showed that selected parameters of twin-wire SAW can meet the requirements to weld the test steel.

Crumb rubber modified asphalt containing 20 percent crumb rubber particles of 30 mesh has been examined by Scanning Electron Microscope (SEM) to observe the microcosmic appearance and the characteristic distribution of crumb rubber particles in asphalt. The SEM pictures reveal that the crumb rubber particles distribute evenly in the asphalt and they are compatible well with asphalt. The shear creep test of crumb rubber modified asphalt was carried out at −10 °C and 40 °C by Dynamic Shear Rheology (DSR). The shearing deformation at different temperature and creep stiffness modulus curve at loading stage of crumb rubber modified asphalt have been measured. The stiffness modulus of crumb rubber modified asphalt is much temperature sensitive and it decays much quick at the early stage of loading than normal asphalt. The rate of decay of stiffness modulus is slow at the subsequent stage and stiffness modulus approaches to a stable value at the final stage at a higher temperature. In addition, Burgers model is suitable to describe and simulate experimental results of viscoelastic properties of the crumb rubber modified asphalt.

A new type of magnesia modification alkali-activated cement was prepared, the strength, setting time, shrinkage ratio and cracking behavior, as well as the composition and structure of the hydration product were investigated. The results indicate that the setting time of this cement is similar to that of the ordinary commercial cements; its strength reaches the standard of 42.5 degree cement, its cracking resistance has been remarkably improved because of the micro-aggregate effect of fly ash and shrinkage compensating of magnesia.

The probability distributions of the critical threshold chloride concentration C _cr, the chloride diffusion coefficient D, and the surface chloride concentration C _s are determined based on the collected natural exposure data, and the probability estimation of reinforcement depassivation in concrete is presented using Monte-Carlo simulation. From sensitivity analysis of mean value for c _cr, c _s, and D on the depassivation probability of reinforcement, it is found that c _cr, c _s, and D respectively has the greatest, smaller, and the lowest effect on the probability of depassivation. Finally the effect of stress state of concrete on the reinforcement depassivation probability is analyzed. It is found that the influence of stress state becomes apparent as exposure time increases.

The primary objective of this study was to develop an autoclaved light concrete (ALC) material with ultra-thermal insulation property and to investigate the relationship between its physical characteristics and mechanical properties. Through tests of dry bulk density and compressive strength, relationship of physical characteristics and mechanical properties of samples were studied, resulting in a material with ultra-thermal insulation property. Scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDX) were applied to analyze the micro-morphology and elemental composition of samples. To identify the product phases, X-ray diffraction (XRD) was engaged. The test results showed that compressive strength and thermal coefficient were reduced with the increasing of aluminum powder within the mixtures. As a result the optimal thermal coefficient and compressive strength of samples were improved to 0.061 W/(m·k) and 1.2 MPa, respectively. SEM, EDX and XRD analyses showed that calcium silicate hydrate and tobermorite crystal were main resultant phases.

The compressive strength, chloride penetration resistance and microstructure of two high-performance concretes were examined under three curing conditions. Curing conditions include standard curing (SC), matched curing (MC, which means sealed concrete specimens curing at temperature controlled box) and matched curing of naked concrete (NMC) according to development law of temperature measured in mass concrete on site. Results indicate that concrete under MC and NMC show higher resistance to chloride penetration than the one under SC. Concrete under MC has slightly lower chloride penetration than those under NMC, but the compressive strength of specimens under NMC was higher than the one under MC at 56 d. In addition, concrete under NMC and MC have higher early strength than under SC, especially at early age. However, the order of curing conditions affecting compressive strength of concrete at 248 day is: SC>NMC>MC.

Hydration characteristics of Portland cement paste with phosphorus slag powder incorporated and hydration kinetics was investigated with SEM, X-ray diffraction, DTA-TG and calorimeter II 80. Results showed that phosphorus slag powder could reduce total amount of hydration products yet had little influence on the type of hydration products. The total amount of heat of hydration was decreased by 49.11% and the final setting was postponed by 2.28 h when phosphorus slag powder substituted 35% Portland cement by mass. The accelerating stage of this composite paste was controlled by catalysis, decreasing stage controlled by both catalysis and diffusion while stabilizing stage by diffusion alone. Hydration resistance and activation energy were reduced and hydration speed was accelerated.

Based on the nearest surface function formula, a quantitative formula to measure the overlapping degree between the interfacial transition zone (ITZ) of neighboring aggregate particles was put forward. The formula was further deduced to quantitatively analyze the influence of the volume fraction of aggregate, ITZ thickness and the maximum aggregate diameter on the overlapping degree between neighboring ITZ. The volume of ITZ was quantitatively calculated in actual concrete by comparing the nearest surface function formula with an approximate method, that is the surface area of the aggregates multiplied by the uniform thickness of the ITZ layers. The results showed that the influencing order of these three factors on the overlapping degree between neighboring ITZ in turn was the interface thickness, aggregate volume fraction and the maximum aggregate diameter; As long as the interface thickness <50 μm and the aggregate volume fraction <50%, the calculated error between two methods mentioned above is about 10 %.

Aging coefficient and creep coefficient are important parameters for creep analysis of any structure. With the aim to obtain those parameters, an experimental investigation is carried out on sealed concrete. Altogether ten specimens were tested, out of which four were for creep, two for shrinkage and remaining four for relaxation test. A year of relaxation test and two years of creep test results were analyzed to compute aging coefficient and creep coefficient. From regression analysis of observed and calculated aging coefficient using formula of Bazant and Kim, modification for aging coefficient is performed and extrapolation equations are generated. Instead of ACI model, B3 model has been used to obtain compliance function as the parameters of B3 model seems more relevant to creep mechanism of concrete compared to that of ACI model.

The influence of binder composition and pore structure of concrete on chloride diffusion coefficient in concrete were investigated by the natural immersion test, MIP test, SEM and EDS test, respectively. The experimental results showed that the effect of binder composition on chloride diffusion coefficient was the comprehensive result of concrete pore structure and binder hydration products, and the porosity and pore size distribution were the main factors that influence the changes of diffusion coefficient. The chloride diffusion coefficient decreased with increasing the curing temperature and the relative humidity. The hydration degree were promoted by improving curing temperatures, and then the porosity of concrete decreased and the proportion of gel pore and transitional pore increased, respectively. But the water evaporation decreased with increasing the relative humidity and then decreased porosity and increased the proportion of gel pore and transitional pore. Additionally, The chloride diffusion coefficient of concrete got the lower value when the appropriate replacement of fly ash in the ranges of 10%–20%, when the double-adding fly ash and slag content was 50%. The porosity increased and the ratio of C/S in C-S-H decreased with further increasing the fly ash content, which led to increase the chloride diffusion coefficient in concrete.

Reducing steel slag (RSS) was mainly acquired from five electric-arc furnace (EAF) steelmaking plants (among them, the products of two plants were carbon steel and those of other plants were stainless steel) for research tests. The chemical properties, compound compositions, activities and contents of main expansive compounds were tested. The results showed that the field sampled RSS had a very high crystallinity and hydraulicity with main chemical compositions close to those of Portland cement. It can be known from the study that in case of C/S ratio higher than 2.0, the main compound compositions are C₂S, C₃S, C₂F and f-CaO. However, after the RSS was stored for six months, an obvious variation occurred with potential pre-hydration in RSS, where the SO₃ content was slightly reduced and the compressive activity index was obviously higher than that at the 28th day.

Stirring uniformity of mixture depends not only on structural parameters of the mixer, motion parameters, but also to a large extent on the using parameters. Based on the analysis of the structure and working principle of mixer, these factors that affecting mixer performance was studied. The mathematical model of mixer performance characteristics was established by theoretical analysis, which associated with the mechanical structure, motion parameters and using parameters. According to the mathematical model, the effects of the mixer filling rate, stirring time, and other using parameters on the uniformity were studied. In each stirring cycle, the minimum number of revolutions formula for shaft was obtained. In addition, in different filling rates, the relationship between stirring shaft rotation laps and stirring uniformity was obtained too. Finally, full-scale experimental verification was conducted.