Synthesis of novel superhard materials under ultrahigh pressure

Superhard materials are solids whose Vickers hardness is beyond 40 GPa. They have wide applications in industry such as cutting and polishing tools, wear-resistant coatings. Most preparations of superhard materials are conducted under extreme pressure and temperature conditions, not only for scientific investigations, but also for the practical applications. In this paper, we would introduce the recent progress on the design and preparations of novel superhard materials, mainly on nanopolycrystalline diamond, B–C–N superhard solid solutions, and cubic-Si3N4/diamond nanocomposites prepared under ultrahigh pressure and high temperature（HPHT）, using multi-anvil apparatus based on the hinged-type cubic press. Bulk materials of all these superhard phases have been successfully synthesized and are systematically tested. We emphasize that ultra-HPHT method plays an important role in the scientific research and industrial production of superhard materials. It provides the driving forces for the light elements forming novel superhard phases as well as the way for sintering high-density nanosuperhard materials.     

提高Si_3N_4结合SiC棚板坯体成型密度的研究

为了获得性能优良的Ｓｉ３Ｎ４－ＳｉＣ棚板，就棚板制造过程中的配料及成型工艺等问题进行了实验研究，探讨了提高Ｓｉ３Ｎ４－ＳｉＣ棚板坯体密度的最佳途径。实验表明：振动成型时，振动时间和振动压力要匹配适当，才能得到最佳的坯体密度。工艺调整适当后，Ｓｉ３Ｎ４－ＳｉＣ棚板实际使用寿命可达５００次以上。     

阻燃机理研究及纸箱制品阻燃防潮剂制备新工艺

探讨了阻燃剂对材料燃烧性质影响的作用机理，介绍了新型阻燃防潮剂的制备方法。研究结果表明，该产品具有涂膜牢固，成本低，无污染等特点。     

邻菲咯啉金属络合物型发光材料的合成及性能研究

设计并通过4步合成了一种新型的联有邻菲咯啉配位基和发光性能优良的萘基的金属络合物型发光材料化合物（PAN）2Zn,并对其进行了表征.研究表明,最佳的反应条件为：硼酸酯用三异丙基硼酸酯,超声功率为175W,超声时间为15 min,C-C偶合反应的催化剂Pb（OAc）2/P（Ph）3=1∶4（mol）,温度为140℃.另外对它的光物理性能进行了初步的研究,结果表明：（PAN）2Zn的最大发射波长为360 nm,并且能够形成激基缔合物,存在明显的溶剂效应,是比较理想的蓝光材料.     

Discussion of the Constitutive Relation on Cyclic Stress-Strain of Engineering Materials

Based on the experimental results and analysis of the cyclic deformation, there is an obvious yield stage on the cyclic stress-strain curve at the stage of small plastic deformation (in room or low temperatures). This phenomenon is similar to that of monotonic tensile curve case. But for the former the deformation amount at which the yield begins is much smaller than that for the latter. The cyclic stress-strain constitutive relation needs to be further studied according to the actual cyclic stress-strain curve. The conventional constitutive equation σ=Aεn is based on the results only corresponding to the cyclic strengthening stage. It is not appropriate for the stage of the small plastic deformation and the stage of yield.     

电解法测气体中微量水时电极材料对氢、氧效应的影响

采用电解法测定气体中的微量水分，存在氢效应、氧效应两种主要的误差来源。不同的电极材料对红效应、氧效应有直接的影响。     

《土壤学》教材编写的实践和教学内容的改革

本文阐述了高等学校教材建设和教学内容改革的重要性;论述了教材编写和教学内容改革的辨证关系;总结了教材编写的实践经验和《土壤学》教学内容的改革。     

搞好电视教材文字稿本的编写保证电视教材的制作质量

从三个方面阐述了电视教材文字稿本的作用，接着又从五个方面就如何编写文字稿本发表了自己的一些看法，意在引起人们对编写文字稿本的重视，使其在电视教材的制作中更好地发挥应有的作用     

振动筛面上振动着的物料对筛体(横梁)的载荷识别

本文应用试验模态分析方法研究了振动着的物料的载荷效应,发现了这种载荷是一系列冲击力的作用,导出了动载荷的表达式,发现了高次谐波共振现象,这些结果可用于振动筛框的动强度设计中。     

负折射物质特性的理论分析

从基本的电磁场理论出发,分析和解释负折射物质的电磁特性,以及负折射物质中的逆Cerenlov现象、逆Doppler现象、负折射率和完美透镜的工作原理,帮助人们更加清楚地认识负折射物质的本质特性,更好地开发和应用好负折射物质.