Advanced Materials Research Vols. 430-432

Abstract: In this paper, the shear strength of different structural planes are tested with the hand portable shear tester in site. The study shows that the shear strength of the structural plane in the granite mass is mainly related to the roughness, the degree of cementation and interlocking of the structural plane. The shear strength of the smooth plane is less, and the plane with interlock partly is larger. In the tests basis, the paper posts out the relation between τ and σ, which can be used to calculate the stability of the landslide。

Abstract: Urea-formaldehyde microcapsules containing epoxy resin is a promising material for self-healing design. The microcapsules were prepared by in-situ polymerization in an oil-in-water emulsion. The microcapsule formation process was monitored using optical microscopy. Surface morphology was observed using field emission scanning electron microscopy. The thermal property of microcapsules was characterized using thermogravimetric analysis. The results indicate that microcapsule wall has a rough outer surface and a smooth inner surface. The microcapsule size is controlled by different agitation rates. Microcapsules have a good thermal stability below 157°C.

Abstract: The precipitation behavior of Cd in an Al-5wt.%Cu based alloy during solidification were investigated, using scanning electron microscopy (SEM) and transmission electron microscope (TEM) observations. It has been found that a novel phase (Al4Cu) is observed except α-Al, θ-Al2Cu, T-Al12CuMn2 phases of Al-5wt.%Cu based alloy during solidification. This phase, with chemical element similar to Al2Cu, was present as closed hexagonal structure, which distributed dispersedly at the edge of grain boundary and adjacent to Al2Cu phase. Moreover, it has the same crystal structure with Cd and satisfies the lattice matching principle, which makes it suitable for the heterogeneous nucleation site for precipitation of Cd.

Abstract: For roller compacted concrete with the admixtures of grinding limestone powder and water quenched iron slag powder (shortly called double admixture RCC) in dam of Jinghong Hydropower station, the raw materials and the mix proportion of the RCC were studied. Then one experiment on in situ shear strength are carried out between hot rise layer and cold rise layer at the altitude of 573.3 meters of RCC in dam block 23 based on the flat push-situ shear test program. The shear strength indexes of hot rise layer and cold rise layer in RCC for Jinghong Hydropower Station are tested by the experiment subsequently. The study results show that the index for interlayer shear strength of the cold rise layer of RCC with 90 days ages in dam are the friction coefficient of 1.12, and the cohesion of 1.22 MPa. The index for interlayer shear strength of the hot rise layer of RCC with 90 days ages in dam are the friction coefficient of 1.32, and the cohesion of 1.24 MPa. The study results also show that the construction processes meet the requirements of the RCC construction and the integrity of hot rise layer of RCC in the dam is better.

Abstract: With potassium dihydrogen phosphate acting as raw material, using grinding and adsorption methods to prepare diffrent kinds of clay-based phosphatic fertilizers. And later, using sodium alginate to coat the fertilizers. Choosing soil leaching method to evaluate their slow-release properties. The results indicate that carrier properties have great influences on slow-release properties, the effect of different carriers are as follows: bentonite > kaolin> common earth. The coordinated role of bentonite and hydrotalcite to the slow-release properties is better than the single role of bentonite. The coating of sodium alginate can improve the slow-release properties of clay-based fertilizers.

Abstract: VC/Fe composite samples were fabricated by sintering at 1050, 1100 and 1150°C in vacuum. The microstructure and mechanical properties of samples were examined, and the relationship of structure and mechanical properties for VC/Fe composite sintered at different temperature were studied. The results show that fracture toughness, hardness and density is increasing obviously at 1050-1100°Cwith the increasing sintering temperature, but the growth trend increases slowly at 1100-1150°C; in whole process with temperature increased, Flexure strength heighten trend obviously. The microstructure of VC/Fe composite changed from particles piled up together to the microstructure particles closely, VC particles set gradually into Fe with temperature increased, and the gap reduced gradually.

Abstract: In this paper, typical defects in aluminium alloys cast by conventional pouring of liquid metal into a cylindrical alumina crucible and an induction melting process are characterized by using macroetching, optical microscopy and scanning electron microscopy. Oxide film defects are generated in both processing methods. Oxide films formed during casting are a major type of defect observed in the microstructures of aluminium alloys products. It has been found that pouring of molten metal into a mould and induction stirring lead to different forms of oxide defects. Under induction stirring, such low-density entrained defects are found to be carried to near the surface of the liquid aluminium alloys and submerged surface oxide films become entangled.

Abstract: In order to avoid the direct discharge of wastewater and the environmental pollution caused by the metal parts quenching treatment, a three-level micro-water washing system is designed, which uses a small amount water to clean the quenched metal parts. The melting-solution confluence method is introduced at the first time to realize the recycling usage of quenching medium in the waste water. The test results show that the use of the technology can achieve maximum water conservation and the quenching medium materials recycling, so that the method does not waste water and the media materials can be recycled more than 90%, and the water consumption is also reduced to nearly 1/20 compared with the original one in the whole production process. The method can be applied not only to shovel type metal parts heat treatment process, also to the related industries.

Abstract: Through creep-recovery and dynamic experiments, the viscoelasticity of polyacrylamide solutions (in short polymer) with different mass concentration are studied, the proportions of elastic part and viscous part in the polymer solution are calculated and the limit of mass concentration called high concentration polymer solution is given. It is indicated that the elastic part of the polymer solution increases firstly and tends to be constant with the increase in mass concentration under low external force condition. The minimum mass concentration of the polymer solution keeping constant elastic part is 1500mg/L. Under low stress and low shear rate conditions, the viscous part of the polymer solution is greater than that of elastic part; but under oil reservoir shear rate (6.283s-1) condition, the elastic part is greater than viscous part, and its elastic part increases with the increase in mass concentrations and the increment becomes smaller.

Abstract: Different from the traditional manufacturing industry, electronics industry is representative of high-tech industry and its financial risk has its own characteristics. In this paper, I choose 2000-2009 electronic financial data of listed companies as samples and use two yuan logistic regression analysis to build an assessment of China's electronics companies in financial risk probability model for the electronic companies to evaluate their own financial risks, provide a simple reference to the views to reduce the financial risk and give the basic risk prediction for the electronics company's mergers and acquisitions objects.