• 已选条件:
  • × 2014
 全选  【符合条件的数据共:5070条】

来源:Advances in Materials Science and Engineering , 2014

作者:Ran Huang;Jiang Jhy Chang;Weichung Yeih;等

使用许可:署名(BY)

预览  |  原文链接  |  全文  [ 浏览:0 下载:0  ]     分享

Specimens were prepared by altering parameters such as aggregate sizes, binder materials, and the amounts of binder used and were subsequently tested by using permeability, porosity, mechanical strength, and soundness tests. The results indicated that the water permeability coefficient and connected porosity decreased as the amount of binder used increased and increased with increasing aggregate size. In the mechanical strength test, the compressive, splitting tensile, and flexural strengths increased as the amount of binder used increased and decreased with the increase of aggregate size. Highly viscous binder enhanced compressive strength, water permeability, and the resistance to sulfate attacks. In the mechanics and sulfate soundness tests, the mix proportion of alkali-activated slag paste used in this study exhibited a superior performance than the Portland cement pervious concrete (the control) did, but the difference in water permeability between the two types of concrete was insignificant. The mix proportions of cement paste containing 20% and 30% silica fume exhibited less mechanical strength than the control did. Moreover, compared with the control, the cement paste containing silica fume demonstrated poor resistance to sulfate attacks, and the difference in the water permeability between such specimen and the control was not noticeable.

    来源:Advances in Materials Science and Engineering , 2014

    作者:Liu Hongwei, Zhang Peng, Chen Gang

    使用许可:署名(BY)

    预览  |  原文链接  |  全文  [ 浏览:0 下载:0  ]     分享

    Molecular dynamics simulation has been performed for investigating the glass transition of Pd-Ni alloy nanoparticles in the solidification process. The results showed that the Pd-Ni nanoparticles with composition far from pure metal should form amorphous structure more easily, which is in accordance with the results of the thermodynamic calculation. There are some regular and distorted fivefold symmetry in the amorphous Pd-Ni alloy nanoparticles. The nanoclusters with bigger difference value between formation enthalpies of solutions and glasses will transform to glass more easily than the other Pd-Ni alloy nanoclusters.

      来源:Advances in Materials Science and Engineering , 2014

      作者:Ramji Koona, M. M. M. Sarcar, Vijaya Kumar Nimmagadda

      使用许可:署名(BY)

      预览  |  原文链接  |  全文  [ 浏览:0 下载:0  ]     分享

      Environmental awareness today motivates the worldwide researchers on the studies of industrial waste reinforced polymer composites. Rapid industrialization has resulted in the generation of huge quantity of solid and liquid wastes such as sugar, paper and pulp, fruit and food processing, distilleries, dairies, and poultries. The redundancy of industrial waste and government regulations have prompted researchers to try for industrial waste reinforced composites. Being low cost, ease of manufacturing, and high mechanical and other properties, an industrial waste represents a good alternative to the most common composites. In the present study, industrial wastes collected from different industries are used as particulate reinforcement in unsaturated polyester matrix and also in polypropylene and investigated dielectric properties. Results reveal that coupling agent treated composites produce improved dielectric strength due to improvement in compatibility between matrix and reinforcement interface. Results also reveal that industrial waste reinforced in polypropylene has more dielectric strength as compared to reinforcement in polyester.

        来源:Advances in Materials Science and Engineering , 2014

        作者:Orhan Özdemir, Ayşe Evrim Saatci

        使用许可:署名(BY)

        预览  |  原文链接  |  全文  [ 浏览:0 下载:0  ]     分享

        Transport and storage properties of sol-gel synthesized, namely, dip coating technique, titanium dioxide (TiO2) thin film over crystalline silicon (c-Si), has been investigated by means of current-voltage (I-V) and admittance analysis within different ambient. Considering the work function of anatase TiO2 film, determined by both FTIR and TG/DTA analysis, silver (Ag) as front metal electrode was chosen to hinder a barrier for charge carriers. Electrical analysis implied that Ag/TiO2/c-Si structure was actually constituted by Ag/TiO2/native silicon dioxide (SiO2)/c-Si [SIS] structure, in which SiO2 layer was identified by FTIR analysis. Consequently, the electrical features of the film were interpreted in terms of SIS diode that is capable of explaining C-V features.

          来源:Advances in Materials Science and Engineering , 2014

          作者:Adriana Mustata, Florin St. C. Mustata

          使用许可:署名(BY)

          预览  |  原文链接  |  全文  [ 浏览:0 下载:0  ]     分享

          The electrical permittivity of the weaves obtained from natural cellulosic yarns or mixed with synthetic fibers was established with capacitor method. The highest value of relative electrical permittivity in case of the woven fabric from natural cellulosic fibers has been observed at the weave made of pure hemp (13.55) and the lowest at the weave obtained from the pure jute—weave packing (1.87). Electrical permittivity value of the pure jute weave packing is comparable to that of the permittivity for the glass thread, when the work conditions are as follows: temperature 25°C and air humidity 35%. The relative electrical permittivity of the weave is depending on the degree of crimping yarns especially in the weft direction, technological density in direction of the warp and weft, and surface mass of the weave.

            来源:Advances in Materials Science and Engineering , 2014

            作者:Michal Prach, Roman Koleňák

            使用许可:署名(BY)

            预览  |  原文链接  |  全文  [ 浏览:0 下载:0  ]     分享

            This paper deals with soldering high-purity brittle, nonmetallic materials such as SiO2, Si, and C (graphite). However, these materials exert poor wettability when using tin solder. Therefore, to reduce the wetting angle, an Sn solder alloyed with active Ti element was used. At a soldering temperature of 860°C and 15 min soldering time, the wetting angle on SiO2 ceramics was 30°, on silicon 42°, and on graphite 52°. All these wetting angles are below 90° and are acceptable for soldering. It has been shown that the bond in all joined materials (SiO2, Si, and C) was of a diffusion character. New intermetallic products were formed on the boundary with nonmetal, thus allowing bond formation. The shear strength of SiO2 ceramics attained an average value of 17 MPa.