自然界样品中~（36）Cl的加速器质谱法测定

描述基于中国原子能科学研究院串列加速器建立的加速器质谱方法，在我国首次测定了自然界样品中的（３６）Ｃｌ，测定的（３６）Ｃｌ／Ｃｌ比值灵敏度为３×１０－１５，所测定的自然界环境样品采自东北连山关铀矿区地下水和矿石、柴达木盆地朵斯勒湖石盐以及河北平原地下水，测定样品中３６Ｃｌ／Ｃｌ比值范围为１０－１２至１０－１４。     

Homophenalenyl cations,new representatives of homoaromatic systems

3b,4-exo,4a,5-Tetramethyl-3b,4,4a,5-tetrahydro-4H-cyclopropa[a]phenalen-5-yl cation and its endo-epimer were proved by NMR method to belong to a new kind of homoaromatic systems: homophenalenyl carbocations.     

Fractional parts of the function <Emphasis Type="Italic">x/n</Emphasis>

Asymptotic formulas for sums of values of some class of smooth functions of fractional parts of numbers of the form x/n, where the parameter x increases unboundedly and the integer n ranges over various subsets of the interval [1, x], are obtained.     

Justification of the averaging method for differential equations with large rapidly oscillating summands and boundary conditions

The averaging method is justified for normal systems of differential equations with rapidly oscillating summands proportional to the square root of the oscillation frequency in the case of the boundary-value problem on a finite interval and for the problem of bounded solutions on the positive semiaxis with boundary condition at its left endpoint.     

基于视觉的车辆与轨道相对振动状态测量方法研究

车辆与轨道相对振动状态对轨道线形测量有重要影响;分析了传统检测车辆与轨道相对振动状态测量方法的缺陷,提出一种基于视觉的车轨相对振动状态测量方法,以轨道建立世界坐标系,以车体建立车体坐标系。考虑相机镜头畸变,建立相机非线性模型,基于机器人手眼方法标定相机与车体,求解相机内外参数。依据车体运动姿态特征,推导基于双目机器视觉的车辆运动姿态偏移补偿计算方法;运用实验平台设计验证实验,通过计算所得的车体振动位移与真实值高度吻合,随着车速增加振动位移误差也随之增大,验证了该方法的正确性和可行性;提供一种车辆与轨道相对振动状态测量方法。     

基于SLAM的连续运动测量坐标转换算法研究

本文基于同步定位与地图创建(Simultaneous Localization and Mapping,SLAM)原理,通过双目视觉系统的坐标转换方法,建立动态坐标系与静态基准点之间的关系,实现连续运动测量。通过实验,设计运动路线,验证坐标转换算法,并得到了建立在世界坐标系下的空间线形曲线。实验结果表明：转换后的坐标,x、y、z三个方向的最大误差不超过0.734mm。     

Mechanism of electrophilic fluorination of aromatic compounds with NF-reagents

Kinetic isotope effects H/D in electrophilic fluorination of aromatic compounds with NF-reagents were investigated. The small values of k _H/k _D (0.86–1.00) are in agreement with the polar reaction mechanism where the Wheland complex decomposition is not the limiting stage. The fluorination of 1,3,5-trideuterobenzene was established by ¹H and ¹⁹F NMR spectroscopy to occur with a 1,2-migration of a hydrogen (deuterium) atom. The analysis of Brown-Stock relationship demonstrated that the activity of NF-reagents exceeded that of many known electrophilic systems including halogenation, but it was essentially less than the activity of elemental fluorine.