取代基对氮和氧自由基稳定性影响的理论研究

用MNDO方法，全构型优化，研究了15个氮自由基4-RC6H4NH，和15个氧自由基4-RC6H4O（R＝－H；－OCH3，－Cl，－F，－CN，－COCH3，－NO2，－CH3，－CF3，－SCH3，－C6H5，－Nh2，－BH2，－PH2，－SiH3）的稳定化能．结果表明：－NH2，－CH3，－OCH3，－F基团对自由基起稳定化作用，－CF3，－NO2；－CN，－COCH3，－BH2基团对自由基起去稳定化作用．苯基对氧自由基有较大的稳定化作用，而对氮自由基的稳定性影响较小．－SCH3，－PH2，－SiH3，－Cl基团表现弱的去稳定化作用．计算和实验结果基本相符．     

Computer-assisted structure elucidation of organic compounds III: Automatic fragment generation from13C-NMR spectra

The interpretation of carbon-NMR spectra is mainly based on the comparison with suitable reference data taken from literature. The whole information contents of¹³C-NMR spectra cannot be utilized by manual interpretation. Therefore a network of interactive computer programs has been developed, which simulates the strategy of the spectroscopist in generating structural fragments from the spectral data. The most important knowledge source for this process is a carbon-NMR data base containing some 17,500 spectra. Structural fragments are generated automatically from this data file and assembled by a model builder to complete chemical structures using constraints derived from the spectral data. A comparison of the experimental carbon-NMR spectrum with the estimated ones allows the generation of a sorted hitlist.For part II see: H. Kalchhauser, W. Robien,J. Chem. Inf. Comput. Sci. 1985,25, 103.     

Computer based screening of compound databases: 1. Preselection of benzamidine-based thrombin inhibitors

We present a computational protocol which uses the known three-dimensional structure of a target enzyme to identify possible ligands from databases of compounds with low molecular weight. This is accomplished by first mapping the essential interactions in the binding site with the program GRID. The resulting regions of favorable interaction between target and ligand are translated into a database query, and with UNITY a flexible 3D database search is performed. The feasibility of this approach is calibrated with thrombin as the target. Our results show that the resulting hit lists are enriched with thrombin inhibitors compared to the total database.     

CAST/CNMR: highly accurate C NMR chemical shift prediction system considering stereochemistry

Accurate, practical prediction of ¹³C NMR chemical shifts has been achieved with a new system, CAST/CNMR, taking account of stereochemistry. The CAST/CNMR system has solved the critical problem of the accurate distinction of differences and similarities in stereochemical structures around a specific carbon, which has not yet been achieved by any other database-oriented system for prediction of ¹³C NMR chemical shifts. CAST/CNMR uses a three-dimensional structural database together with a ¹³C NMR spectral database. Absolute/relative configurational and conformational structural information are described by the CAST (CAnonical-representation of STereochemistry) coding method. This paper provides an overview of the CAST/CNMR system, and describes its application to two natural products as examples.     

Molecular structure of carbonyl bromide as studied by gas electron diffraction

The molecular structure of COBr₂ has been determined as follows by an analysis of electron diffraction intensity: r_g(CO) = 1.178 ± 0.009 Å, r_g(C-Br) = 1.923 ± 0.005 Å and θ°_α(Br-C-Br) = 112.3 ± 0.4°. The uncertainties represent estimated limits of error. The observed systematic trends in the bond lengths and bond angles in carbonyl and thiocarbonyl halides are discussed.     

全自动电脑横机控制系统的设计

介绍了一种全自动电脑横机控制系统的新型分层体系设计.在该体系中,花型准备系统是基于Windows的开放式编程系统,通过编译自动生成编织指令数据文件,提供了独有的可扩充布纹库.下位NC硬件控制系统无需操作系统支持,便可完成对整个编织过程的实时监控,故障诊断,修改编织参数及测试执行部件等功能.新型的分层体系实现了上、下位机的功能独立,并保持了良好的人机交互界面和便捷的操作性,真正实现了全自动和智能化设计.     

TH型区间值模糊正规子群

本文在区间值模糊集空间上，引入了幂等区间范数ＴＨ，在此基础上，定义了ＴＨ型区间值模糊正规子群，并研究了它的一些性质和结构特征，从而拓广了区间值模糊集的理论。     

系统拓扑结构的TDLRtree时空数据库索引表示法

本文提出了一种新的基于TDLRtree时空数据库索引结构来表示系统拓扑结构的方法。整体上采用以时间为轴的方式对系统拓扑结构情况进行记录,通过一部分对象采用单链表,另一部分对象采用双链表的方式来简化对系统拓扑结构的重构。该方法避免了传统重构中重构树的复杂过程,通过对原有树变化后的遍历来代替了重构树,简化了重构的算法,提高了系统效率。教学实践结果表明,该方法在通过变电站仿真系统教学应用中不仅提高了学生的学习兴趣,同时加深了学生对课程的理解,收到良好的教学效果。     

一种从关系数据库提取本体的方法

本体可以很好地解决异质数据源的语义异构问题。关系数据库模式到本体的转换是用本体进行信息集成的基础技术之一。设计了一种从关系数据库自动提取本体的方法,给出了关系数据库到本体的转换规则,最后给出了系统的模型和实现技术。     

基于会员的超市管理系统分析与设计

为了适应商业企业进销存信息管理的自动化、标准化和科学化,设计了具有大规模、高效率的超市管理系统。该系统针基于超市现有的管理情况,以计算机为工具,对超市的会员、采购、进货、销售、员工、客户等信息进行处理的人一机系统,其能及时、准确地反映超市进、销、存中的各项工作的当前状态,同时,利用UML对系统的核心部分进行动态模型设计。目标系统是一个数据库应用软件,其最终目的是通过此软件来实现超市各个环节的管理。