对称中心

By taking advantage of a corollary of the Desargues theorem and the corresponging extension of Desarguesian configuration, the concept of stereohomology has been defined in projective geometry and presented based on homogeneous coordinates. Consequently, a series of geometrical transformations, such as central projection, parallel projection, centrosymmetry, translation transformation, reflection, rotation transformation, which can be contained in it or derived from it have also been analytically defined.

利用Desargues定理的一个推论和引申的Desargues图形，给出"空间透射"在射影几何意义下基于齐次坐标表象的解析定义，从而解析定义了可蕴涵其中的中心投影、平行投影、中心对称、平移、反射等几何变换以及可由此衍生出的旋转变换。

The original symmetry point and have seriously deviated from, if you want to make a balance between the development of the city, there are two approaches, one is the original economic development of backward areas, for example, to Nancheng huge investment, it's rapid economic growth; also There is a way to move the center to make it balance, if it is still definitely in line for Chang'an Street, Beijing should not balance the development is therefore imperative to the city centers to China.

原来的对称点和已经严重偏离，如果您想之间的平衡发展的城市，有两个办法，一个是原来的经济发展落后地区，例如，南城巨额投资，经济的快速发展增长；也有一种方法可以移动中心，使之平衡，如果它仍然是绝对排在长安街，北京不应该平衡发展，因此必须在城市中心，中国。

The coordination polyhedron around Ce3＋ is a distorted square antiprism, and the two independent molecules are connected by π-π stacking interactions to form a noncentrosymmetric dimer.

中心Ce3＋的配位多面体为变形双帽四方反棱柱，两个分子之间以π-π堆积连接，生成一个非中心对称的二聚体。

The endocyclic Sn atoms exist in a distorted triginal bipyramidal geometry with the coordination number of 5. The exocyclic Sn atoms form 6 significant bonds and exist in a distorted octahedron geometry.

化合物12的X衍射单晶测定表明，化合物是以Sn2O2四元环为中心的中心对称二聚体结构、内环锡为5配位的畸变三角双锥结构、外环锡为6配位的畸变八面体结构。

Of or relating to diatoms of the class Centrales, distinguished by their radially symmetrical form.

中心类硅藻的中心类硅藻的或与之相关的，以其辐射状对称形态为特征

At the target surface impinged by the synthetic jet, the temperature field is symmetric with the lowest filed in center. The heat transfer coefficients also take on the same trends with centrosymmetric waves, which means that the best cooled area is the stagnation.

在冲击靶板上，整个冲击区域呈现出中心温度最低的近似圆形的对称性分布，对流换热系数曲线呈现出中心对称的波峰分布形状，表明自耦合射流驻点区换热最强。

The water chamber takes the shape of tilting cube, in favor of uniform distribution of cooling water on tube plate surface. The tube bundle is divided into two groups of zygomorphy according to the bisection system and it has eight support clapboards. The siphonopore center of each clapboard increases a certain distance corresponding to that of two tube plates and the cooling tube takes the shape of arch. The two-way cooling water of bisection flows through the condenser in opposite direction so as to improve the distribution of heat load for tube bundle. Around the throat of condenser, the final stage low-pressure heater, air extraction tube, intake device of bypass exhaust and the like are deployed.

它的特点是：水室呈倾斜立方体形状，有利于冷却水流在管板面上均匀分布；由于采用对分制，管束相应地分为左、右对称的两组，并且管束设有八块支撑隔板，每块隔板的管孔中心相对于两端管板的管孔中心依次抬高一定的距离，以使冷却管呈拱形状；对分制的两路冷却水以相反方向流过凝汽器，从而改善管束的热负荷分布；在凝汽器喉部布置了末级低压加热器，抽汽管道及旁路排汽接受装置等。

It was not symmetry about weld centerline the area which the material had deformed. The plasticized materials looked like a slantwise vase in the center of the weld.

塑性变形的区域关于焊缝中心不对称，塑性材料在焊缝中心形成类似于倾斜&花瓶&状的形貌。

Lenses are optical elements with 2 refractive surfaces. These can be centered sphericalally, rotationally

这些透镜是有中心的，如球面的或旋转对称的，而不是非旋转对称的。

The otherfaces of the building address the adjacent commercial precinct with lively asymmetry and transpositions of scale.

朝着市政中心的两个立面采用了对称的形式，另外两个立面用非对称和转化尺度的手法与附近商业建筑进行了对话。

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。