Advanced Materials Research Vols. 476-478

Abstract: Combined with the mutual relationship of minor rural road network construction and the development of rural social economy, the quantitative evaluation index system is established. In the specific index design, this paper totally consider the features of the rural regions and reflect the requirement and ecological functions of the minor rural road. Based on fuzzy entropy weight part of double-base the evaluation method of the minor rural road network solutions than the election method, comprehensive embody the rural road traffic system sustainable development.

Abstract: diamonds have superior performance unmatched by other materials. The nano-crystalline diamond (nano-crystalline diamond powder and nano-crystalline diamond films) is a new construction material and functional material with diamond excellent properties and nano material characteristics. Such dual bizarre characteristics determine its wide application. The application developed predicts its sound prospects, which, however, requires researchers to conduct studies and development.

Abstract: The martensitic transformation, crystalline structure, microstructure and shape memory effect of the Ni53.25Mn21.75Ga25 (at.%) alloy are investigated by means of Differential Scanning Calorimetry (DSC), X-ray diffraction (XRD), Transmission Electron Microscope (TEM) and the standard metal strain gauge technique. The XRD results showed that the Ni53.25Mn21.75Ga25 alloy is composed of cubic parent phase at room temperature. TEM observation proved that the typical twin martensite is tetragonal structure and tweed-like contrast which is typical image for the parent phase. A large reversible transformation strain, about 0.54%, is obtained in this undeformed polycrystalline alloy due to martensitic transformation and its reverse transformation. This transformation strain is also increased to 0.65% by the external magnetic field. It is believed that the effect of the magnetic field on the preferential orientation of martensitic variants increases the transformation strain.

Abstract: The dispersion of TiH2 particles stirred into an Al-9Si melt, to produce a precusor for subsequent foaming, has been studied. The effects of processing parameters have been related to measured changes in the viscosity of the melt. The results show that 610°C is the key point in the temperature - viscosity relationship. Below 610°C, the viscosity increases greatly with decreasing temperature and only above this temperature, when the viscosity increases slowly with temperature, can good dispersions be obtained. The uniformity of the foaming agent dispersion is improved by increasing the melt temperature, stirring speed and stirring time. However, clusters of foaming agent still exist with rotational speeds of 3000rpm and stirring for 30s. Extrusion of the precursor can be used to improve the uniformity of the foaming agent such that very few foaming agent clusters exist and the variation in foaming agent concentration with position in the precursor is very small.

Abstract: We provide a general framework for solving constrained optimization problems, this framework relies on dynamical systems using a class of nonlinear Lagrangian function, we construct a first order derivatives based and a second order derivatives based differential systems. Under this framework, We show that the exponential Lagrangian system as the special case is discussed.

Abstract: Abstract. Single crystalline SnS nanowire arrays have been synthesized by sulfurating the Sn nanowire arrays which were prepared with the electrochemical deposition. The obtained SnS nanowire arrays are charactered with the XRD, SEM, TEM and the UV/Visible/NIR spectrophotometer. And the results indicate that the nanowires with an average diameter of 50 nm and a length of several tens micrometers, which same with the as prepared Sn nanowires. There are two absorption peaks indicate with the direct and indirect bandgaps about the orthorhombic SnS nanowire arrays.

Abstract: The periclase-hercynite brick performance after different re-firing cycles was researched under different atmosphere. The results are shown that under the oxidizing atmosphere, the brick after re-firing would lead to the mutual diffusion of iron ions in both magnesium substrate and hercynite particles, which would further lead to ring cracks around hercynite. After the brick was re-firing at CO atmosphere, the mutual diffusion of magnesium and iron ions was even more severe, which formed magnitude of magnesia-hercynites and magnalium spinels. SEM results are shown that the porous structure around the hercynite could damage more severe.

Abstract: Abstract: Drilling platforms in ice-infested regions tend to vibrate intensively, threatening the safety of personnel. Cone with holes as vibration-absorbed material is added to platforms so that the failure mode of ice sheet is changed and resonation of platform is avoided. Simulated analysis of breaking length of ice sheet is made and the comparison between observed breaking lengths and predicted ones is made and it is found that the results are in good agreement.

Abstract: This paper presents a novel strategy for synthesis of carbon nanomaterials using the Cstaple biomaterials – starch as the starting materials. The carbonhydrate were vaporized by arc under helium, which leads to a large amount of monodispersive carbon nanoballs with range of 30-70nm in diameter. In addition to carbon nanoballs, some carbon nanocapsules were occasionally observed in products. Transmission electron microscopy (TEM), energy dispersive X-ray (EDX) and X-ray diffraction (XRD) were employed to characterizing products. The growth mechanism of carbon nanoballs is discussed briefly in terms of the precursor composition and process parameters.

Abstract: A light porous sintered material was prepared with red mud, fly ash, silica fume as the main raw materials, mixed with a certain amount of foam, by the technology of casting, calcination and etc. The influence of calcined temperature on the flexural strength, compressive strength, shrinkage and other properties of sample was studied. The microstructure of sample was characterized by scanning electron microscopy (SEM) and then the sintering mechanism was studied. The results showed that the optimum calcined temperature was 1150°C, and for the best sample, its bulk density was 691kg•m^-3, compressive and flexural strength were 4.2MPa and 3.2MPa, thermal conductivity coefficient was 0.110W• (m•K)^-1, firing shrinkage was 3.9%.