Tungsten combustion in impact initiated W-Al composite based on W(Al) super-saturated solid solution

Element W can effectively improve the density of energetic structural materials. However, W is an inert element and does not combust in air. To change the reaction characteristics of W, 60 at.% Al was introduced into W through mechanical alloying. XRD analysis shows that after 50 h of ball milling, the diffraction peak of Al completely disappears and W(Al60) super-saturated solid solution powder is obtained. Further observation by HAADF and HRTEM reveals that the W(Al60) super-saturated solid solution powder is a mixture of solid solution and amorphous phase. Based on the good thermal stability of W(Al60) alloy powder below 1000℃, W(Al60)-Al composite was synthesized by hot pressing process.Impact initiation experiments suggest that the W(Al60)-Al composite has excellent reaction characteristics, and multiple types of tungsten oxides are detected in the reaction products, showing that the modified W is combustible in air. Due to the combustion of tungsten, the energy release rate of the W(Al60)-Al composite at speed of 1362 m/s reaches 2.71 kJ/g.

单位年终福利状况的探究——基于太原市各单位员工年终福利状况的研究

随着人民生活水平的提高,福利问题成为人们日渐关注的话题,而年终福利则集中体现中国人对福利的集体诉求。运用二手资料分析、抽样调查法及访谈法,得出员工年终福利已由传统的物质阶段逐步向服务阶段过渡,整体呈现物质、货币和服务福利三者并存,并以货币福利为主的结论。同时发现单位开放性越强,其福利的弹性和多元化模式就越突出。研究反映出一些国有单位的福利制度无法发挥出应有作用,且单位间福利差距的拉大加剧了分配秩序的紊乱,对社会公平和社会保障的实现起到了负面的作用。要解决现有福利分配问题,单位可从公平、异质性、形式及人情方面加强考虑。