晶体中化学键的研究Ⅲ具有NiAs结构的二元间隙化合物

本文用LCBO方法研究了NiA_B结构二元化合物的能带结构特点,从而探讨了这类化合物的导电性。     

无机三原子分子的离域π键和分子结构

本文探讨了用群论和Huckel分子轨道法半定量处理无机三原子分子（或离子）的离域π健，求出它们的π分子轨道能级，并讨论它们的稳定结构及对分子磁性的解释。     

Peptide synthesis through evolution

Ribosome-catalyzed peptide bond formation is a crucial function of all organisms. The ribosome is a ribonucleoprotein particle, with both RNA and protein components necessary for the various steps leading to protein biosynthesis. Evolutionary theory predicts an early environment devoid of complex biomolecules, and prebiotic peptide synthesis would have started in a simple way. A fundamental question regarding peptide synthesis is how the current ribosome-catalyzed reaction evolved from a primitive system. Here we look at both prebiotic and modern mechanisms of peptide bond formation and discuss recent experiments that aim to connect these activities. In particular, RNA can facilitate peptide bond formation by providing a template for activated amino acids to react and can catalyze a variety of functions that would have been necessary in a pre-protein world. Therefore, RNA may have facilitated the emergence of the current protein world from an RNA or even prebiotic world.Received 4 December 2003; received after revision 13 January 2004; accepted 15 January 2004     

应用带有非线性连接权的神经网络识别水泥胶结质量

为了解决石油测井中水泥胶结质量识别误差大的问题,采用改进的双发双收补偿式声波测井仪进行幅测量,综合利用首波幅度信息来消除仪器的倾偏心,泥浆对声信号的衰减以及仪器灵敏度变化等引起的不可避免的误差,研究并阐述了优越于统计识别方法的带有非线性连接权的神经网络方法,能使2层神经网络具有3层BP网络的功能,且消除了隐含层的麻烦,并简化了运算,提高了运行速度,在具体应用中,先进行声幅刻度以全取得合格样本,再构造神经网络进行学习训练以得到非线性权值和阈值等参数,然后在测井过程中自动进行水泥胶结质量的识别。通过实测井应用表明,应用人工神经网络方法能实时进行水泥胶结质量的识别,其识别正确率远高于相对幅度法,效果显著。     

Construct 2D nanostructure of co-adsorbed dipyridyl derivative by stabilization of hydrogen bond and long alkyl chains

The self-assembled structures of 4, 4‘‘-dionoyl-2,2‘‘-dipyridyl and its co-adsorption with stearic acid on highly oriented pyrolytic graphite (HOPG) have been studied by the scanning tunneling microscopy (STM). As a result, 4,4‘‘-dionoyl-2,2‘‘-dipyridyl forms a planar trans conformation in two cases, and through the co-adsorption with stearic acid, 4,4‘‘-dionoyl-2,2‘‘-dipyridyl and stearic acid form a well-ordered nanostructure.     

对聚氨酯中氢键强度分布的理论探讨

本文应用平衡热力学理论,时Coleman等人提出的氢键强度分布模型进行新的探讨。首次导出了能反映氢键强度分布的热力学方程.本文还进一步从导出的热力学方程出发,建立了计算氢键解离热焓和熵变化的公式.     

从头计算法研究分子间的氢键相互作用

首先概述了氢键的静电相互作用理论。然后以一个典型氢键体系──氢氰酸水的计算过程和结果为例，讨论了从头计算法（ａｂｉｎｉｔｏ）在研究分子间氢键方面的应用，以及此体系氢键相互作用的机理。     

非质子溶剂对醇类稀溶液红外光谱的影响

在分析影响醇类稀溶液红外光谱因素的基础上，以溶剂的电子给予数，折光率和相对介电常数为参数，对几种醇类稀溶液的红外位移进行了关联计算。结果表明，标准偏差稍高于实验误差，比目前常用的关联式有所改善。     

三价铬镀层强化及结合机理

研究直流与脉冲两种电源条件下三价铬溶液电刷镀工艺性能．应用Ｘ射线衍射仪等仪器测定了镀层的截面组织、镀层与基体的结合强度、镀层的内应力以及镀层的硬度，并在测试结果的基础上探讨了镀层的结合与强化机理．研究表明：镀层强化归因于镀层内晶粒极其细小造成的强化以及镀层内应力造成的强化；镀层与基体的结合方式有：机械连接、接近原子尺寸的连接和扩散连接．这些结合方式存在于基体与镀层结合面的不同部位并促成镀层与基体结合良好．