查询词典 circle geometry

In this thesis,the AM1,MNDO,MINDO/3(mainly AM1)and INDO/S-CI semiempirical MO methods were used toinvestigate the excited-state intramolecular protontransfer reactions of salicylic acid derivatives—salicylic acid,methyl salicylate,salicylaldehyde,o-hydroxyaceto-phenone,salicylamide and 3-hydroxy-picolinamide (6 conformers and 2-3 anion species);2-(2'-hydroxy-5' methylphenyl) benzotriazole(4 conformers),2-(2' hydroxyphenyl) benzimidazole (3 conformers and 3anion species),Bis-2,5-(2-benzoxazolyl)hydroquinone(3 conformers),2-(2'-hydroxyphenyl)benzothiazole(2conformers) and 7-azaindole dimer (2 conformers).Theinvestigations were described as follows.Geometry optimization,relative stability andhydrogen bonding energy First,for sylicylic acid derivative molecules,the AM1,MNDO and MINDO/3 methods were used toinvestigate ground-state geometry optimization,energies,relative stabilities and hydrogen-bondingenergies on the five kinds of the molecules(designing 6 conformers and 2-3 anion species).Comparing with experimental data,the optimizedgeometry,the order of stability,the hydrogen-bonding energies and the distances between O-O in O-H..O hydrogen bonds by AM1 method were in agreementwith the experimental data,however,the C-C bondlengths optimized by MNDO and MINDO/3 were longer,C-O and O-H bond lengths were shorter;for C-N bondlengths,the results opitimized by MNDO method werethe same as those by AM1 method,nevertheless the C-Nbond lengths given by MINDO/3 method were muchshorter.For some sylicylic acid derivatives(e.g.methyl salicylate,salicylamide),the order ofstabilities on the conformers given by MNDO andMINDO/3 methods were not in agreement with theexisting conformers deduced by experimental methods,and the hydrogen bonding energies calculated by MNDO.and MINDO/3 methods were smaller.Second,the studyon the other systems found that the optimizedgeometry of the proton-transfered product with INDOmethod could not be obtained,only could theoptimized geometry of reactant be obtained,and thecalculated hydrogen bonding energies were greater.Many results of calculation indicated that the studyon the excited-state intramolecular proton transferreaction system using AM1 method was suitable andreliable.

本论文用AM1、MNDO、MINDO/3（主要是AM1）和INDO/S-CI半经验分子轨道方法对水杨酸衍生物系列——水杨酸、水杨酸甲酯、水杨醛、O-羟基乙酰苯酮、水杨酰胺和3-羟基吡啶酰胺（6种异构体和2-3种阴离子）；2-（2'-羟基-5'-甲基苯基）苯并三〓唑（4种异构体）；2-（2'-羟基苯基）苯并咪唑（3种异构体和3种阴离子）；2，5-二间氮杂氧茚氢醌（3种异构体）；2-（2'-羟基苯基）间〓杂硫茚（2种异构体）和7-〓吲哚二体（2种异构体）的激发态分子内质子转移反应在以下几个方面进行了较系统的理论研究：几何构型优化和相对稳定性及氢键能首先以水杨酸衍生物系列分子为例，用AM1、MNDO和MINDO/3方法考察了5种分子（每种分子设计6种异构体和2-3种阴离子）的基态几何构型优化，能量、相对稳定性和氢键能计算，通过和实验数据进行比较，AM1方法给出的优化几何构型、稳定性次序、氢键能和O—H。。。O氢键的0—0距离与实验数据吻合最好，MNDO和MINDO/3方法优化的C-C键长偏长，C-O键和O-H键长偏短；对于C-N键长，MNDO和AM1优化结果差别不大，而MINDO/3给出了过短的C-N键长，MNDO和MINDO/3方法给出的有些水杨酸衍生物分子（如水杨酸甲酯和水杨酰胺）异构体的稳定性次序和实验上推测的可存在异构体结果不一致，MNDO和MINDO/3方法给出的氢键能偏低，对其他体系的研究发现INDO方法常常不能得到质子转移产物的优化几何构型，只能得到反应物的优化构型，并且估算的氢键能偏高，大量的计算结果表明AM1方法对本论文研究的激发态分子内质子转移反应体系是适宜和可靠的。

The crystal structures have been determined by single-crystal X-ray diffraction.Cadmium atoms in compounds 1 and 2 show an eight-coordinated distorted square-antiprismatic geometry and a seven-coordinated distorted pentagonal bipyramidal geometryrespectively. Copper atoms in compounds 3 and 4 show a six-coordinated distorted threeprismatic geometry and a four-coordinated distorted tetrahedral geometry respectively.

所有配合物的晶体结构都通过单晶X-射线衍射确定：配合物1中的镉离子周围显示八配位的扭曲四方反棱柱构型；而配合物2中的镉离子周围显示七配位的扭曲五角双锥构型；配合物3中的铜离子周围显示六配位的扭曲三棱柱构型；配合物4中的铜离子周围显示四配位的扭曲四面体构型；配合物5中的锌离子周围显示六配位的扭曲八面体构型。

Using the principle of Projectiv e geometry and Analytic geometry,we have intact analysed about the cut and hand in line of taper and Geometry proved the form produced by the special-position -leve and the general-position-level.

利用射影几何和解析几何的原理对圆锥截交线进行了完整的分析，对特殊位置截平面与一般位置截平面产生的截交线的形状进行了几何证明，为截交线的形状判别与绘制提供了理论依据。

Possible speed means that in the good climatic and traffic condition, the automobile is only influenced by the geometry line shape of the highway; the driver with skilled technology drives the travel speed that the automobile may reach while going along certain highway.Possible speed is decided by geometry line shape of the road mainly, its change can reflect the change state of the line shape of the road, and the geometry line shape of the road play a very important role to emergence of the traffic accident, so the change of the possible speed can reflect the security state of the road.

可能速度主要由道路的几何线形决定，它的变化可以反映道路线形的变化状况，而道路的几何线形条件对交通事故的发生起着举足轻重的作用，因此可能速度的变化情况能够直观的体现道路的安全状况。

Based on the framework of wheat morphology visualization, the 3D geometric modeling technologies of wheat organs were investigated, and the organ geometrical models were developed with characteristic architecture parameters. The model included three submodels: leaf geometry, stem geometry and wheat spike geometry submodels.

本研究以小麦作物为对象，在提出小麦形态可视化技术框架的基础上，首先研究了小麦不同器官的三维几何建模技术，构建了基于器官形态特征参数的几何模型，包括叶、茎秆和麦穗几何模型。

Using the two-stream fluid model, the linear dispersion relation is derived assuming a two-dimensional spatial geometry. Two cases are considered, one is that the 2D spatial geometry is defined by the plane containing the two counterstreaming electron populations and the perturbation wave vector , and the other is that the geometry is defined by the plane being vertical to the two counterstreaming electron populations .

对高能束流和电子回流构成的双流系统，建立冷等离子体流体模型，采用简正模分析方法，分别考虑扰动波矢在平行于电流传播方向的平面上和在垂直于电流传播方向的平面上这两种情况，推导了不稳定性的色散关系。

According to the principle of the diameter of a circle corresponding to the right angle and the principle of short side for little angle in right triangle, projecting the initially-chosen point to the hyper-planes of the linear equation group in which every linear equation can be regarded as a hyper-plane and the projection points can be obtained. The initially-chosen point, and one arbitrary projection point, and the solution point are all on the surface of the relative hyper-geometry ball, therein-to, there is a projection point which is nearest to the solution point and it can be regarded as the next iterative initially-chosen point, so the solution problem of the linear equation group can be changed as an iterative problem of approaching the solution on the surface of a hyper-geometry ball.

根据直径对应的圆周角足直角以及直角三角形中短边对小角的原理进一步知道，当将初始点向线性方程组中各个方程所代表的超平面上投影得到投影点时，初始点和其任何一个投影点及方程组的解点都将位于一个相应的超球面上，其中必定存在一个投影点离问题解点的距离最短，即把该点作为下一次迭代的初始点，从而可将线性方程组求解的问题变成球面上逼近解点的迭代问题。

Function graphing and analyzing: 2D, 2.5D functiongraphs and animations, extrema, root, tangent, limit,derivative, integral, inverse; sequence of number: arithmetic progression, geometric progression; analytic geometry: vector, line, circle, ellipse,hyperbola and parabola; solid geometry: spatial line, prism, pyramid, cylinder, cone, dado and sphere; Ability to save graph as data file or bmp file; Ability to save animation as AVI file; Ability to move, zoom in, zoom out and rotate the scene.

函数图表和分析：2D， 2.5D 函数图表和动画，极值，根，正切，极限，导数；序列号：等差数列，等比级数；解析几何：向量，矢量，直线，圆，椭圆，双曲线和抛物线；立体几何：空间线，棱柱，三角锥，圆柱，圆锥体，梯形台和球体；保存图形为数据文件或者图像文件的功能；保存动画为 AVI 文件的功能；移动，缩小，放大和旋转场景的功能。

The basic principle is based on spherical astronomy and elementary geometry of the trajectory mapping method based on the observation of a celestial body zenith distance, then the ship is located in order to sing the next point as the center of this satellite zenith distance of the ship's position as the radius of the circle, observing the same two objects, or objects at different times of the two observations, we can get two ship's position round, then the ship must have been a point of intersection of two ship's position on the circle.

其基本原理是建立在球面天文学和初等几何中的轨迹作图法基础上的，观测一个天体的天顶距，则航船就位于以星下点为圆心，此星天顶距为半径的船位圆上，观测两个天体或者不同时间同一天体的两个观测值，就可以得到两个船位圆，则航船一定在两个船位圆的一个交点上。

Therefore this imaging system can realize two kinds of X-ray radiology: reverse geometry X-ray and X-Scan imaging, and several CT scanning methods, such as equiangular fan-beam CT, equispatial fan-beam CT, helical/spiral CT, cone-beam CT with circle orbit, cone-beam CT with circle-plus-line orbit.

这样就可以实现倒置结构的X射线成像方法、等角扇束的扫描方法，以及本文所提出的凹面源加点探测器的锥形束扫描方法，而且还避免了使用成组点探测器带来的性能不一致性。

Yet, Edith says, there was always money in the bank.

但是Edith说，她的银行户口里面总是有钱。

We have created a series of files that resolve this problem--one for each day of the 40 days of purpose.

我们制作一系列的档案去解决这问题---一个为标竿40天中的每一天。