نتایج جستجو برای: metal element
تعداد نتایج: 395479 فیلتر نتایج به سال:
We report terahertz metamaterial waveguides based on the concept of composite right/left-handed transmission-lines. The waveguides are implemented in a metal-insulator-metal geometry fabricated with spin-coated Benzocyclobutene and contact photolithography. Angle-resolved reflection spectroscopy shows strong resonant absorption features corresponding to both right-handed and left-handed (backwa...
gears are one of the most critical components in power transmission system of an automobile and also many rotating machinery. many studies have been conducted on optimum gear design. the main objective is to design different aluminium metal matrix composite spur gears before and after optimization. aluminium metal matrix material composites are preferred mostly due to their low density. also th...
slab method of analysis has been used for solving metal forming problems for a long time. however it has been restricted to plane strain and axisymmetric problems due to limitations in its formulations. in this paper a new formulation has been proposed so that it could be applied to three dimensional problems in metal forming. a parametric slab has been considered in this analysis and the force...
In this review we compare the three existing sets of theoretical yields of zero metal massive stars available in the literature. We also show how each of these three different sets of yields fits the element abundance ratios observed in the extremely metal poor star CD 38 245. We find that, at present, no theoretical set of yields of zero metal massive stars is able to satisfactorily reproduce ...
in recent years, in order to reducing die design and manufacturing costs, multi point forming technique has gained an increasing interest because of its high flexibility. in this process, the conventional fixed shape solid die sets are replaced with a pair of opposite matrices of controllable elements. in this paper, the fundamental principles of multi-point forming was described and the possib...
We investigated the potential of the South African high-biomass Ni hyperaccumulator Berkheya coddii to phytoextract Co and/or Ni from artificial metalliferous media. Plant accumulation of both metals from single-element substrates indicate that the plant/media metal concentration quotient (bioaccumulation coefficient) increases as total metal concentrations increase. Cobalt was readily taken up...
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