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采用三维全息原子场作用矢量(3D-HoVAIF)对32个吡咯类抗艾滋病药物进行结构参数化表征,并与其活性建立定量构效关系。分别采用多元线性回归(MLR)和偏最小二乘(PLS)进行建模,建模的复相关系数(R2cum)、交互校验复相关系数(Q2cum)和模型的标准偏差(SD)分别为R2cum=0.914、Q2cum=0.812、SD=0.236(MLR);R2cum=0.836、Q2cum=0.719、SD=0.314(PLS),结果均优于文献值(R2cum=0.667,Q2cum=0.581,SD=0.420)。所建模型具有良好的稳定性和预测能力,表明3D-HoVAIF能够较好地表征该类分子的结构,值得进一步推广应用。  相似文献   
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本文根据构造变形的特点,系统地研究了构造力学中有限应变理论的图解方法,提出来用度规张量描述一点应变状态的几何解析法,对于用变形梯度表示的变形梯度圆结构进行了论证,并用几何图形清晰地描述极分解理论中各种量的关系.最后通过各种不同方法计算了构造变形中常见的简单剪切变形,用以说明和比较各种有限应变图解法的特点.  相似文献   
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The conditions for fracture of anisotropic bodies and theirgeometry in stress space are proposed in this paper.The an-alytical formulae expressing the fracture conditions are es-tablished from the viewpoint of energy theory for crack pro-pagation.In stress space the limiting surface corresponding to thefracture conditions derived for anisotropic solids is quadra-tic.It is an ellipsoid in case the mean stress is greaterthan zero and it is hyperboloid in case the mean stress is smal-ler than zero.The conclusions formed by the author in the present paperhave certain generality.Some results obtained by predeces-sors appear to be special cases with respect to the presenttheory.  相似文献   
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选用三种天然磷片石墨(大同混目石墨固定碳含量为88.78%,内蒙古兴和混目石墨固定碳含量为95.67%,山西芮城-185石墨固定碳含量为86.47%),在不同的条件下,用稀酸和氟化物溶液进行处理,考察了它们脱除矿物质的作用。经100℃用稀酸溶液处理2h,然后用氟化物溶液在70℃左右处理2.5h,大同混目石墨固定碳含量可达99.93%,内蒙兴和混目石墨固定碳含量可达99.80%,芮城-185石墨固定  相似文献   
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This paper proposes the approximate methods of calculation for research on inhomogeneous finite strain fields in geologic bodies by means of the "Principal Axis" theory of continuum mechanics. The methods are to obtain the principal strain orientations at finite points in the earth's crust based on the information and data provided by the actual strain measurements of deformation marked objects in the field, or by the research on crystalline fabrics in rocks, and then to obtain two sets of smooth orthogonal principal strain trajectories through mathematical treatments. A network composed of two sets of orthogonal curves shows the deformation character of the rock, and correspondent strain components satisfy compatibility conditions. The curvatures of curves are used to describe the compatibility conditions in this paper. An analytic solution of a strain field is obtained when the two sets of lines can be simulated by analytic function; the magnitudes of principal strains at every point may be obtained b  相似文献   
6.
地壳岩石非均匀有限应变场分析   总被引:1,自引:0,他引:1  
本文运用连续介质力学中的“主轴”理论,对地质体非均匀有限应变场的研究提出一个近似计算方法。这一方法是以野外变形标志物的实际应变测量或岩石晶体组构研究所提供的某些信息和数据为基础,得出有限点的主应交方位,然后进行数学处理,得到两组光滑的正交主方位线,这两组正交曲线网格反映了岩石的变形特征,并满足应变的协调条件。  相似文献   
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李俊芬  李晋增  张彩红  韩玉英  秦曦  董川 《应用化学》2013,30(10):1139-1143
合成了具有强电子给体和拉电子能力基团的新化合物:9-乙基-3.-咔唑亚甲基-(2,4-二硝基)苯腙,研究了其光谱性质和光物理行为.结果表明,化合物在溶液中,随着溶剂极性的增大,发生了分子内电子转移,激发态和基态的偶极矩差值(μE-μG)为4.530 D,并在强极性溶剂中出现了有趣的双荧光发射.随着其浓度增大,会形成二聚或多聚体,荧光发射发生红移.  相似文献   
8.
According to the peculiarities of tectonodeformation this paper systematically researches the graphic method of finite strain theory in tectonomechanics, proposes a geometrical analytic method describing the strain state of a point with metric tensor, expounds and proves the structure of deformation gradient circle, and clearly illustrates the relations of various quantities in polar decomposition theory. Finally, a simple shear deformation which often occurs in tectonodeformation was calculated through various different methods in order to explain and to compare the peculiarities among various graphic methods of finite strain.  相似文献   
9.
本文根据固体断裂裂纹扩展的能量条件,探索各向异性体的断裂条件及其应力空间几何,结论是:在恒温条件下,断裂的应力空间曲面为二次曲面.当流体静应力大于零时,为椭球面;当流体静应力小于零时,为单叶双曲面.本文所得的结论具有一定的普遍性,前人的一些结论可作为本文的特殊形式.  相似文献   
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