政府是住房保障中不可或缺的角色,本文从政府这项公共职能出发,厘清保障性住房政策的发展历程,透析政府在其中的角色转型,有助于明确保障性住房改革的方向,坚定政府所要承担的历史责任,进而实现新常态下“居者有其屋”的人居梦想.探索发现,新中国建立以来,尤其是改革开放以来,中国保障性住房的政策演变过程就是一个渐进的市场化适应性过程.根据保障性住房的保障力度及其主要特征,可以将保障性住房政策大致分为三个阶段:
According to the characteristics of sealing materials in aerospace field, a new structure of the three-dimensional braided quartz fiber preform was introduced to be thermal seals.Compression rebound p
The finite element analysis of the 3d full 5 direction braided composites elastic properties always replaced the elastic properties of the whole model with the elastic properties of the interior cell.
In order to investigate the effects of preform structure on thermal conductivity of needle-punched quartz fiber reinforced epoxy resin composites, the quartz fiber preforms were madeup of layers of no
In order to investigate the effects of preform structure on thermal conductivity of needle-punched quartz fiber reinforced composites, the quartz fiber preforms were made up of layers of non-woven qua
利用碳纳米管巨大比表面积特性,将浮动催化法制备的连续大面积碳纳米管海绵体浸润到石墨烯溶液中,再经牵伸、热压和高温处理后得到碳纳米管/石墨烯复合材料,实现一维碳纳米管与二维石墨烯材料的有机复合,并对复合材料的力、热性能进行研究分析。结果 表明：溶液浸润法可有效地将石墨烯填充到碳纳米管海绵体内部形成三维空间网络结构的纳米复合材料,高温退火可实现碳纳米管与石墨烯的共价键键合,其面内热导率高达560W/m
本文对客机复合材料球面框进行了分析和研究，通过有限元计算，对球面框上的加强筋对结构屈曲性能的影响展开深入研究。通过建立有加强筋和无加强筋两种结构方案，利用有限元模型进行静力和屈曲分析计算，表明了客机复合材料球面框的加强筋对球面框结构的屈曲性能和稳定性有一定的改善作用，但增加加强筋后球面框的应力、应变和位移变化都不大。因此，球面框结构设计时采用加强筋的意义不大。
This paper focuses on the research and development of the "Conformal Antenna Composite Structure (CACS)" with load-bearing, shape maintaining and communication capabilities.In contrast to common Confo
In this study, a model for bending of composite angle-ply laminate Kirchhoff plate is developed based on the anisotropic modified couple stress theory.The new model contains only 1 internal material l
碲(Te)化物纳米线因为其优异的热电性质在热电器件领域应用前景广阔，引起了学者的广泛关注。对于碲化物纳米线的制备及形貌控制方面的研究成为该领域研究的热点。本研究采用多元醇还原法制备Te纳米线。首先将不同配比含量的TeO2粉末、KOH、PVP及乙二醇注入到三颈烧瓶中，加热待温度稳定后快速注入水合肼并保温一段时间，从而制备出Te纳米线。