CADCSC软件系统人机界面设计

本文论述了CADCSC软件系统的界面设计。提出了适合各种用户的、由多种交互方式组成的混合人机交互界面;为控制系统的计算机辅助设计提供了统一的命令表达方式和统一的运行界面;介绍了其中界面设计一致性与灵活性。     

平面弹性连杆机构的KED分析

本文放弃了文献中引用的运动学假设和瞬时结构假定,考虑了刚体运动和弹性变形运动之间的耦合项,分析了梁的横向位移对轴向应变的影响。利用虚位移原理和达明贝尔原理,建立了构件和系统的运动微分方程式。以四杆较接机构为例,进行了KED分析。从所得结果可以看出,本文更好地反映出弹性对机构动态误差的影响。     

我院申请国家自然科学基金项目情况分析

本文分析了“八五”以来国家自然科学基金项目的现状、前景及我院申报国家自然科学基金项目的获得资助率，并从六个方面探讨提高我院申报国家自然科学基金项目获得资助率的措施与方法．     

用钼蓝反应动力学方法作微量磷的分光光度测定

提出用ｄ－葡萄糖试剂做钼蓝反应的还原剂测定磷的动力学方法。用吸光度监测反应速度，用假一级反应的关系式测定了反应速度与磷浓度的线性范围为０．６～２．５μｇ／ｍＬ。用内标法计算五种土壤样品中的含磷量，分析结果与常规方法比较，符合程度令人满意。     

单电极直流电弧炉电热特性理论研究

运用电磁理论与流体静压力原理,导出了电弧自身的电磁向心压缩力以及电弧对熔池冲力的解析式。又运用辐射传热原理,导出了单电极电弧对熔池与炉衬辐射传热的解析式。解析式揭示出电弧自身电磁向心压缩力、电弧对熔池冲力,单电极电弧对熔池以及对炉衬辐射传热的规律。     

Prediction of the structure of a receptor-protein complex using a binary docking method.

To validate procedures of rational drug design, it is important to develop computational methods that predict binding sites between a protein and a ligand molecule. Many small molecules have been tested using such programs, but examination of protein-protein and peptide-protein interactions has been sparse. We were able to test such applications once the structures of both the maltose-binding protein (MBP) and the ligand-binding domain of the aspartate receptor, which binds MBP, became available. Here we predict the binding site of MBP to its receptor using a 'binary docking' technique in which two MBP octapeptide sequences containing mutations that eliminate maltose chemotaxis are independently docked to the receptor. The peptides in the docked solutions superimpose on their original positions in the structure of MBP and allow the formation of an MBP-receptor complex. The consistency of the computational and biological results supports this approach for predicting protein-protein and peptide-protein interactions.     

混合氯化稀土催化合成DOP,DOM和DOA

本文报道:价廉的混合氯化稀土,对合成DOP等增塑剂有明显的催化效果。产品精制简单,转化率高,有应用前景。     

求Ramsey数最优下界值的递归算法

要确定每个具体的Ramsey数的数值是相当困难的,至今人们只求出了为数很少的几个Ramsey数的数值.人们在研究Ramsey数性质的同时,也在估计Ramsey数的数值,得出了某些Ramsey数的下界值,但工作进展缓慢.本文提出了一种计算Ramsey数最优下界值的递归算法,该算法利用当今关于Ramsey数的最新结果,能得出Ramsey数的目前最优下界值.1 算法描述不妨将本算法定名为G,参数个数为1个以上(可变化),算法允许递归调用,其输出值为Ramsey数的目前最优下界值.C(k_1,k_2…,k_n)表示以k_1,k_2…,k_n作为输入,通过算法G所得到的输出结果,即C(k_1,k_2…,k_n)表示的是G算出的Ramsey数N(k_1,k_2,…,k_n;2)的目前最优下界值,其中N(k_1,k_2…,k_n;2)的含意与文献[2]中有关含意相同.算法G:     

用栅板剪切干涉法确定应力强度因子

本文介绍了一种用栅板剪切干涉法确定应力强度因子的新方法,阐明了该方法的基本原理与实验技术,通过三点弯曲梁确定了Ⅰ型裂纹应力强度因子,实验结果与理论上近似计算结果相符合。     

Short alanine-based peptides may form 3(10)-helices and not alpha-helices in aqueous solution.

Short alanine peptides, containing 16 or 17 residues, appear to form alpha-helices in aqueous solution. But the main spectroscopic analyses used on helical peptides (circular dichroism and nuclear magnetic resonance) cannot distinguish between an alpha-helix (in which the ith residue is hydrogen-bonded to residue i + 4; ref. 9) and the next most common peptide helix, the 3(10)-helix10 (i-->i + 3 hydrogen-bonding). To address this problem we have designed single and doubly spin-labelled analogues of alanine-based peptides in which the nitroxide spin label forms an unbranched side chain extending from the sulphur atom of a cysteine residue. Here we report the circular dichroism, Fourier-transform infrared and electron-spin resonance spectra of these peptides under helix-forming conditions. The infrared absorbance gives an amide I' band with a frequency that is substantially different from that observed for alpha-helices. The electron-spin resonance spectra of doubly labelled helices show that the ranking of distances between side chains, around a single turn (residues 4-8), is inconsistent with an alpha-helical structure. Our experiments suggest that the more likely peptide geometry is a 3(10)-helix.