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Aiming to characteristics of structure and transmitting medium of gas pipe with high temperature and high pressure, considering the coupling effect of static pressure and temperature, the thermal structure coupling model based on steady-state heat conduction is established according to the finite element theory. So method and process of numerical simulation on thermal structure coupling analysis are proposed. Simulation analysis is carried out for the gas pipe of a dry-gas compressor. The variation characteristic of inner-outer wall is revealed under the different temperature. The results indicate that the numerical modeling and simulation of thermal structure coupling of gas pipe with high temperature and high pressure can be realized. It can provide valuable reference opinions for site construction, real-time monitoring and safety analysis of pipe.

In order to improve reliability of automobile transmission system and its running stability, this paper raises a reliability assessment calculation method. This method considers dependent failure of the parts, material strength degradation with increasing load times and uncertainty of load times in micro and macro scopes to explore main factors affecting the system reliability. The feasibility of this method has been validated by the example analysis. As a result , material properties of each gear parts, torques and load times play key parts in reliability of the system.

Compression tests of Mg-4Al-3Ca-1.5Zn-1Nd-0.2Mn Magnesium alloy as-extruded had been performed in the compression temperature range from 200°C to 350°C and the strain rate range from 0.001 s1to 1 s1and the flow stress data obtained from the tests were used to develop the power dissipation map, instability map and processing map. The optimum parameters for hot working of the alloy had been determined. According to the processing maps, the most optimal temperature range is 280°C to 350°C and most optimal strain rate range is 0.001 S-1to 1 S-1.

The deformation behavior and constitutive equation of Mg-4Al-3Ca-1.5Zn-1Nd-0.2Mn alloy were investigated using hot compression tests at the temperatures range of 200, 250, 300, and 350°C with the constant strain rates of 0.001, 0.01, 0.1 And1 s-1. The influence of strain was also incorporated in the constitutive equation by considering the effects of strain on material constants which are consist of A, α, β, n and activation energy Q. The predicted flow stress curves using the proposed constitutive equations well agree with the experimental results of the flow stress for experimental Alloy.

The type I collagen was used to prepare self-assembly film, the UV-vis spectrophotometer and Fluorescence spectrophotometer were employed to characterize those self-assembly films. The Fe (NO3)3 and CuSO4 were used as the additive to investigate the effect of the type I collagen film. It was found that the character spectra of collagen solution and self-assembly film were different, the Fe (NO3)3 enhanced the 408nm fluorescence emission peak, and CuSO4 caused a new emission peak at 399nm. The changes in the fluorescence of films suggest that the metal salt could affect the type I collagen self-assembly.

Based on performance comparison of PDM equidistant and conventional elastomer lining, the impacts on the PDM performance were presented with different equidistant lining thickness. According to the Mooney-Rivlin two-parameter model and the Poisson radio equaling to 0.5, the elastomer is incompressible during the calculation and its relational material parameters such as elastic modulus and shear modulus were determined. The PDM stator and rotor curve equations were established according to hypocycloid theory. The lobe configuration is 3:4, the performance comparisons were investigated including deformation and Mises stress between conventional and equidistant elastomer lining of PDM with contact model. The test data pointed out torque, rotation speed, volumetric and overall efficiency variation results with the motor pressure difference changing from 1.93MPa to 5.90MPa. The presented results could be used for PDM design optimization and performance improvement.

Tilt-up is a method for constructing concrete wall rapidly and economically without formwork. A large number of tilt-up structures have been constructed in North America and other developed countries, and it will also be an acceptable term for new construction in China. Tilt-up process can reduce the cost of labor and materials in wall construction. As the damage of earthquake, the connection of the tilt-up building is the most important part which attracts more attention to engineers. At the end of this paper, details of connection are discussed as the codes introduced.

To analysis the microstructure and properties of super-high strength Al-Zn-Mg-Cu alloys containing Zr ,Ni and Mn, the apparatus of SEM、TEM、and Tensile machine was used. The results show that the microstructure was fine and homogeneous, the phases became finer for the alloys with adding Zr, Mn, Ni than the alloy with Zr only after solid solution. The ultimate tensile strength of the alloy was 850MPa and the elongation was 5% respectively at peak aging.

We repaired osteochondral defect of rabbits with tissue-engineered osteochondral graft composited by chondrocyte and nanohydroxyapatite/chitosan (nanoHA/CS) scaffold. Bone marrow mesenchymal stem cells (BMSCs) were cultivated with chondrogenic differentiation medium and induced to chondrocyte. Seed the chondrocyte into the bottom of the nanoHA/CS scaffold with a boot-shaped structure and cultivated the composite in the chondrogenic differentiation medium for 2 weeks. Osteochondral defect of 4mm in diameter and 8mm in depth were created in the epicondyle of femur. The composite graft were grafted into the defects while the composite graft induced without boot-shaped structure as the matched group. Specimens were harvested at 4th and 12th week post operation respectively, general and histological examination was performed and graded. We found BMSCs were induced to chondrocyte after cultivated with chondrogenic differentiation medium. The interstice ratio and diameter of nanoHA/CS scaffold is 90% and 150μm. The scaffold has good adhesion with chondrocyte. The coupling between the bone and the cartilage in the experimental group is superior to the matched group obviously. This results indicate that tissue-engineered osteochondral graft composited by boot-shaped structure can be a new approach to attempt to overcome the technical surgical difficulties identified in this study.

The p-toluene sulfonate- pillared layered double hydroxide(PTS-LDH) was synthesized by co-precipitation method, unsaturated polyester resin/ PTS-LDH composites were prepared by solution blending and solidifying. The X-ray diffraction was used to characterize the structure of the composites. The thermal stability and fire properties of composites have been studied by thermo- gravimetric analysis, limit oxygen index and UL94 burning test. The results show that the interlayer space of original LDH was 0.775nm, which was increased to 1.73nm for PTS-LDH and 2.077 nm for unsaturated polyester resin/ PTS-LDH composite. The addition of PTS-LDH improved the flame retardancy of unsaturated polyester resin. Limit oxygen index of unsaturated polyester resin/ PTS-LDH composite was increased to 23.30 % from 21% of the pure resin, the char residue rate increased by 3.7% and the speed of horizontal burning was decreased by 20.24%. The vertical burning test (UL-94) results indicated that the materials achieved V-2 grade.

The Mg-9Al-3Zn-0.6Mn-xNd alloys, preformed with φ300mm size, has been prepared by spray forming technology under a protective atmosphere. The microstructure and mechanical properties have been investigated by XRD, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and strengths tested mechine. As a result, the precipitate phases in the alloys were the finest when the Nd content was 1% compared the alloys with the Nd content were 2% and 3%, the size of precipitation phases are between 1-2um and there are phases like Mg2Ca，Al2Ca，and MgZn2in the alloys. After extrusion, recrystallization microstructures were found in the alloys. The tensile strengths are between 400-450MPa and the yield strengths are between 350-370MPa respectively as the differences content of Nd in the alloys after heat treatment.

Quasi-static tests of three specimens of steel-concrete composite fabricated shear wall were performed to investigate its seismic behavior. The test results indicate that horizontal cracks run through the interface between the wall and the base beam, diagonal cracks appear on the whole prefabricated concrete shear wall. The specimens fail in the mode of bending-shear, the hysteretic curves according to the test were full, it means that they have better seismic bearing capacity.

Field evidence is presented showing that egg production rate and hatching success in the copepod Calanus sinicus were greatly modified during a major late-winter diatom blooms in the Jiaozhou Bay (Yellow Sea). The diatom species composition in this period had shifted to a dominance of Skeletonema costatum and Thalassiosira sp, and comprised about 65% of phytoplankton population among all six sampling stations. Calanus sinicus were examined to determine the effects of the diatom bloom on reproduction and recruitment. The results of egg production rate and hatching success were significantly decreased with the increase of chlorophyll a concentration, indicating that diatom bloom induced negative effect on the copepods population recruitment.

Tilt-up is a method for constructing concrete wall rapidly and economically without formwork. A large number of tilt-up structures have been constructed in North America and other developed countries, and it will also be an acceptable term for new rural construction in China. Tilt-up process can reduce the cost of labor and materials in wall construction. With the application of the recycled concrete in tilt-up construction, which is being researched in the Beijing University of Civil Engineering and Architecture, tilt-up building can be has a larger benefit obviously in the suburbs and rural area. With the benefit of both techniques, the paper finally introduces the application prospect in China.

In this study, an instrument for circulating BOD analysis by microbial sensor has been developed. A Pseudomonas. sp immobilized by PVA, was employed for sensitive material BOD sensor. The measure period was about 8 minutes. Both relative error and analytical standard deviation are less than 5%. The instrument has the advantages of high autoimmunization and short measure period. The accuracy and stability of the instrument measured up the national standard by testing different type waste waters and national standard samples.

Mg-Al-Zn alloys of 2% Nd and without Nd, which produced by spray deposited method, were heat treated at different solid-solution and the same aging treatment. The microstructure and hardness were analyzed by SEM , XRD and HV tester. The experimental results showed that Nd can make the spray deposited magnesium matrix grains tiny evenly, formed the second phase particle Al3Nd, and increased the hardness value. With the rise of solution temperature, the hardness of without Nd magnesium alloy show that rise firstly and then fall rapidly, but the 2%Nd magnesium alloy hardness increase all the time with the rising of solution temperature, and the hardness value increase sharply to the highest 181Hv after 448°C/3h+205°C/24h.

In nonlinear dynamic analyses of RC structures based on fiber-based discretization of member cross-sections, the constitutive model used to represent the cyclic behavior of reinforcing steel typically plays a significant role in controlling the structural response especially for nonductile systems. The accuracy of a fiber-section model is almost entirely dependent on the ability of both the concrete and reinforcing steel constitutive material models to represent the overall inelastic behavior of the member. This paper describes observations related to the fundamental properties of reinforcing steel such as buckling, hardening, diminishing yield plateau and growth of curvature, Bauschinger effect, and low-cycle fatigue and strength degradation that are relevant to the overall task of developing an accurate material model for use in seismic response analysis of reinforced concrete structures.

During earthquake, the inelastic action in the plastic hinge regions of structures and bridges results in significant reversed deformation and failure of the critical components because of cumulative damage. To simulate seismic behavior of structure members and develop a simplicity damage criterion for circular concrete filled steel tubular (CFT) columns subjected to a series of earthquake excitations, an experimental study was undertaken to investigate the cumulative damage and relationship between low cycle fatigue life and displacement amplitude. Two types of large scale circular CFT columns with different kinds of seam weld and inner concrete compressive strength including nine specimens were tested under quasi static loading with constant and variable cyclic amplitudes. The test data were evaluated with the fatigue model relating deformation and fatigue life. Fatigue life expressions for application in damage-based seismic design are developed.

Based on the solidification features of ductile iron and affecting factors for ductile iron shrinkage defect, the model of the ductile iron solidification is built and put forward a new defect predictive method EIECAM (Enclosed-Isolated area Expansion and Contraction Accumulation Method) model to predict defect. in DECAM, the liquid shrinkage, solidified shrinkage and graphitizing expansion during solidification are computed dynamically in the enclosed-isolated area , and the effect of graphite expansion on the wall movement is also accounted. Based on this method end cover of QT500 ductile iron casting is simulated and made the defect predictive, study its solidification process and the defect generation position, and make the experimental identification on the defect. It is resulted that the method can be able to predict the casting defect authentically.

One-dimensional ZnO nanopowder was prepared by chemistry liquid-phase method with polyethylene glycol (PEG) as additive in [Zn(OH)4]2- premonitory solution. TEM results showed that the nanopowder with the diameter of 30~50nm has the structure such as the good crystal state and well-defined crystallographic surfaces. The UV–Vis absorption revealed that the ZnO nanopowder have strong absorption in the UV region. The function of polyethylene glycol and the effects of solvent conditions were discussed.

Kaolinite-glucose intercalation compound was synthesized by the intercalation of polar organic big molecule dodecylamine and then displaced by glucose in the layer of kaolinite. XRD, FT-IR, TG and DSC were used to study the reaction process and the characters of the products. The results indicated that the basal spacing of kaolinite increased to 2.280 nm from 0.717 nm, and the hydrogen bonds were formed between dodecylamine NH and kaolinite Si-O after dodecylamine intercalation. Kaolinite-dodecylamine intercalation compound was stable below 295 °C. After displacement reaction by glucose, the basal spacing of kaolinite increased to 3.364 nm, and the intercalation rate reached 87%, the hydrogen bonds were formed between glucose C=O and kaolinite inner surface hydroxyl. Kaolinite-glucose intercalation compound was stable below 302 °C.