Studies on the reaction between Laccase ando-methoxyphenol by microcalorimetry

The reaction between Laccase ando-methoxyphenol have been studied by LKB-2107 batch microcalorimetry system. Thermodynamic parameters Δ _r H _m , ΔG _o , ΔG _T ^≠ and kinetic parameters (K _m ,k ₂) have been determined. The process of the reaction has been analyzed from changes in energy by using the transition state theory. Two methods for enhancing catalytic power of Laccase are proposed. The results shown that formation of an enzyme-substrate complex is “anticatalytic”. The enter and sole source of catalytic power is the stabilization of transition state; reactant-state interactions are by nature inhibitory and only waste catalytic power. Supported by the National Natural Science Foundation of China Wang Tianzhi: born in 1968. Ph D     

离子响应淀粉接枝共聚聚丙烯酸钠智能性凝胶的合成及性能

用辐射法制得的高吸水性淀粉接枝聚丙烯酸钠水凝胶，在一定离子强度的溶液中表现出的体积收缩现象，是一种新型的人工智能材料．在不同的离子强度、离子价态和凝胶体积状态下，这一材料所表现出来的不同体积收缩规律符合Ｄｏｎｎａｎ规律．收缩后的凝胶在一定条件下可以快速溶胀，表现出一定的伸缩可逆性．通过设计的简单传动装置，可大致得出水凝胶在伸缩过程中做功的大小．     

微电极在 Ni(OH)_2 使用寿命测定中的应用

采用粉末微电极技术，通过循环伏安法对Ｎｉ（ＯＨ）２使用寿命的测定进行了研究．通过控制微电极孔穴深度，使电极过程不受液相扩散控制，从而提高了电极的充放电电流．在电极循环过程中，放电峰电流随着循环次数而变化，从而反映出电极的循环性能．在每次循环扫描过程中，充电深度达到７５％，能够满足常规检测的要求．对含Ｃｏ与不含Ｃｏ两种Ｎｉ（ＯＨ）２的检测结果说明，Ｃｏ有利于延长Ｎｉ（ＯＨ）２的寿命，这一点与已往的结论是相符的．应用这一技术，完成一次测试所需时间不到１０ｈ．这种方法对于研究Ｎｉ（ＯＨ）２掺杂元素对寿命的影响是非常快速而有效的．     

锡铁山办矿模式研究

从技术经济指标、经济效益等横、纵向多角度比较分析，充分揭示出锡铁山矿务局通过招投标方式将主体矿山生产承包出去的办矿模式所产生的转换企业经营机制作用及其整体效益；同时分析了招投标竞争方式下对承包方产生的激励机制及其带来的效果．文中对完善该办矿模式进行了探讨．     

Interface bond mechanisms of ceramic-cemented carbide compact insert

Conclusion Ceramic-cemented carbide compact inserts have been developed by hot-pressing sintering techniques, the upper part of the compact insert is of Al₂O₃ + TiB₂ ceramic material, while the base part of the compact insert is of WC + Co cemented carbide. The compact insert makes full use of the advantages of the high hardness of ceramic materials and the high strength of cemented carbide, and its mechanical properties are just between that of Al₂O₃ + TiB₂ and WC + Co. SEM, XRD and electron microprobe analysis showed that element diffusion and formation of new phases are the main causes for the bond of Al₂O₃ + TiB₂ with WC + Co in the interface.