透射光栅衍射效率研究

透射光栅广泛应用于 X光能谱测量 ,为获得定量的 X光能谱 ,首先在北京同步辐射源上对透射光栅的衍射效率在多个入射 X光能量点进行了实验标定 ,获得了透射光栅衍射效率的实验结果。为模拟透射光栅衍射效率实验标定结果 ,发展了一个新的透射光栅衍射效率计算模型 ,该模型不同于国外已发展的矩形栅线模型和梯形栅线截面模型 ,而是假设透射光栅栅线具有准梯形截面。模型计算结果与实验标定结果符合很好。     

基于有限元的超高速平面磨床整机动力学建模及模态分析

以150m／s超高速平面磨床为研究对象,利用PRO／E建立其各部件的三维几何模型,利用HYPERMESH进行有限元前处理建立各部件的三维有限元模型,在此基础上对机床结合部进行定义得到磨床整机动力学模型．并利用有限元计算软件ANSYS进行整机模态分析,初步识别了该类型磨床结构的薄弱环节,为超高速平面磨床结构的改进设计提供依据．     

Stress dependence of growth mode change of epitaxial layered cobaltite γ-Na0.7CoO2

We report stress dependence of growth characteristics of epitaxial γ-Na_0.7CoO₂ films on various substrates deposited by pulsed laser deposition method. On the sapphire substrate, the γ-Na_0.7CoO₂ thin film exhibits spiral surface growth with multi-terraces and highly crystallized texture. For the γ-Na_0.7CoO₂ thin film grown on the (1 1 1) SrTiO₃ substrate, the nano-islands of ∼30 nm diameter on the hexagonal grains are observed. These islands indicate that the growth mode changes from step-flow growth mode to Stranski-Krastanow (SK) growth mode. On the (1 1 1) MgO substrate, the large grains formed by excess adatoms covering an aperture between hexagonal grains are observed. These experimental demonstrations and controllability could provide opportunities of strain effects of Na_xCoO₂, physical properties of thin films, and growth dynamics of heterogeneous epitaxial thin films.     

自由选课模式下课程表安排的数学模型

通过把课程表安排的要求转换成满足若干条件的矩阵，建立了自由选课模式下排课问题的数学模型，并给出了选取最优方案的评价标准。     

帽形加劲复杂卷边槽钢柱偏压性能试验研究

对共计18个简支试件进行偏心受压试验,分析并研究了未加劲、腹板中央帽形加劲、腹板和翼缘中央帽形加劲3种截面复杂卷边槽钢的极限承载力、失稳模式及变形特征等特性.结果表明:有效形心移动对偏心承压构件的承载能力有很大影响.在板件中央设置帽形加劲可以适当减小板件的宽厚比,显著提升受压构件的极限承载力及钢材利用率,但畸变屈曲在构件失稳模式中起控制作用.在同等条件下,板件中央帽形加劲偏压构件的承载效率提升了15%~70%.     

谈离散数学网络课件教学

论述使用离散数学网络课件教学的模式,并介绍了网络课件用于教改实践中的作用和使用中的应注意的问题.     

Reaction Mechanism Investigation Using Vibrational Mode Analysis for the Multichannel Reaction of CH_3O+CO

ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅｍｅｔｈｏｘｙｒａｄｉｃａｌ (ＣＨ3Ｏ)ｉｓａｎｉｍｐｏｒｔａｎｔｉｎｔｅｒ ｍｅｄｉａｔｅｉｎｔｈｅｐｈｏｔｏｃｈｅｍｉｃａｌｏｘｉｄａｔｉｏｎｏｆｈｙｄｒｏｃａｒｂｏｎｓｉｎｔｈｅａｔｍｏｓｐｈｅｒｅ ,1 3ａｎｄｐｌａｙｓａｓｉｇｎｉｆｉｃａｎｔｒｏｌｅｉｎｔｒａｎｓ ｆｏｒｍｉｎｇｎｉｔｒｉｃｏｘｉｄｅｔｏｎｉｔｒｏｇｅｎｄｉｏｘｉｄｅ .4 Ｓｉｍｉｌａｒｌｙ ,ｔｈｅｒｅａｃｔｉｏｎｍｅｃｈａｎｉｓｍｓｏｆｈｙｄｒｏｘｙｌａｎｄｃａｒｂｏｎｍｏｎｏｘｉｄｅ5,6ａｎｄｏ…     

Adjusting the chromatographic properties of poly(ionic liquid)‐modified stationary phases by substitution on the imidazolium cation

Poly(ionic liquid)‐modified stationary phases can have multiple interactions with solutes. However, in most stationary phases, separation selectivity is adjusted by changing the poly(ionic liquid) anions. In this work, two poly(ionic liquid)‐modified silica stationary phases were prepared by introducing the cyano or tetrazolyl group on the pendant imidazolium cation on the polymer chains. Various analytes were selected to investigate their mechanism of retention in the stationary phases using different mobile phases. Two poly(ionic liquid)‐modified stationary phases can provide various interactions toward solutes. Compared to the cyano‐functionalized poly(ionic liquid) stationary phase, the tetrazolyl‐functionalized poly(ionic liquid) stationary phase provides additional cation‐exchange and π‐π interactions, resulting in different separation selectivity toward analytes. Finally, applicability of the developed stationary phases was demonstrated by the efficient separation of nonsteroidal anti‐inflammatory drugs.     

高师院校学生数学学习模式研究

本文通过对调查结果的分析,研究了高师院校数学学习模式的现状,提出改进学习模式的若 干建议。     

基于遗传算法优化的机器人非奇异终端滑模控制

六自由度并联机器人是一个强耦合、高度非线性的系统,针对此特性研究了非奇异终端滑模控制方法,为改善其运动品质,结合指数趋近律的思想,给出了系统的控制律.利用李雅普诺夫（Lyapunov）理论验证了存在建模误差和外部干扰时六自由度并联机器人控制系统的稳定性,确保了控制系统的鲁棒性.为了进一步减少滑模控制的抖振,提高系统收敛速度和跟踪性能,采用了遗传算法来优化非奇异滑模面和控制律的参数.仿真结果表明：提出的控制策略参数优化后能使机器人的轨迹跟踪稳态误差趋近于零、系统调整时间短、驱动器控制律平滑,达到了高性能的位姿控制.