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The rice husk powder was modified by polymer (lactic acid) (PLA) and Maleic anhydride (coupling agent, MAPP). Composite material was prepared in the way of melt blending. The mechanical properties, water absorbability of rice husk/polymer (lactic acid) (PLA) composites, and the relations between these properties and microscopic characteristics were investigated. The result showed that, with the increasing content of rice husk power, the maximum bearable tension and tensile strength increased; Water absorbability after 2 hours’ immersion hadn't significant change, but after 24 hours’ immersion, the water absorbing capacity had obvious addition. The study also showed that coupling agent could significantly reduce the water absorbability of composite materials; The use of scanning electron microscope (SEM) found that the interface became smoother, the adhesion between PLA and rice husk powder became closer when add the coupling agent to the rice husk powder, it also could well explain the differences between water absorbability and mechanical properties.

A new performance test system is presented in this paper, as we all known, hydraulic support is the most important equipment in mechanized coal mining. Electric hydraulic valve, as the key components, consist of electromagnetic pilot valve and mechanical valve bodies. When electromagnetic pilot valve hasnt enough driving force, precursor core wont work normally. The test stand can measure relationship between displacement and force of electromagnetic pilot valve. First of all, electric hydraulic valve is introduced simply, then detailed designing process. The test Bench includes measurement and control system, as well as working theory.

Basedon the present situation of the domestic comprehensive tunneling temporary supporting technology, machine support and temporary support device is researched. This paper is on the basis of the previous design simple optimization.The design enhances temporary support level and improves its ability to support for a long time, in some extent, increases the strength of roof support. The optimization is described in detail.By adding a hydraulic cylinder,it can make each lever own supporting ability and ensure support stability. Organizationstructure and three dimensional graphics are drawn in the paper.The force analysis is carried. Finally appropriate position is determined.

The electric vehicle is a newly powered walker alternative tool with good environmental benefits and low operating cost. The subsidy on the product innovation, environmental protection and energy saving is not issued in time because of policy lag, and therefore management measures can't keep pace with the times. This leads to the currently inefficient marketing of household electric vehicle, and its difficult operation situation in our country. This article begins with the promotion and operation mode of household electric vehicles, and puts forward some proposals for the popularization of household electric vehicle which can provide some reference for management department, the electric vehicle manufacturers, and the electric vehicle sales and service agencies.