球面

We then introduce a conformal invariant quantity which is formulated in terms of the square of the length of the trace free part of the second fundamental form and the mean curvature, and prove that if this quantity is bounded above by that value of the Clifford torus then x is either a totally umbilical sphereor a conformal Clifford torus.

接著我们介绍一个由第二基本型式迹为零部份的张量长度平方与平均曲率形成的保角不变量，并证明此保角不变量的上界若为Clifford环面之值，则x不是全脐球面就是Clifford环面的保角类。

Manufacture of big aperture lightweight paraboloidal mirror is one of the key techniques for the research of the Cassegrain optical system.

研制某卡塞格林光学系统的关键技术之一是通光口径超过1000mm的轻质抛物面主反射镜。该反射镜相对口径为1/2，减重率为65%，是目前国内最大口径的轻质非球面反射镜。

For testing the concave ellipsoidal mirror of Three Mirror Cassegrain optical system, a slab compensated auto-collimation method is suggested.

针对TMC光学系统凹椭球面主镜的检验，本文提出了一种平板补偿的自准检验方法。

The designed method of optical imaging system and optical scanner have been described. This optical system consists of two aspherical mirrors i.e. Cassegrain system, the designed datas have been given.

描述了光学成像系统和光学扫描系统的设计方法，光学系统是由两个非球面反射镜所组成，并给出了光学系统设计的各种数据。

The main component of the celestial globe is a hollow bronze globe, with crisscross grids on the spherical surface, which are used to delineate the exact position of celestial bodies.

整个铜球可以绕一根金属轴转动，转动一周代表一个昼夜，球面与金属轴相交于两点：北天极和南天极。两个极点的指尖，固定在一个南北正立着的大圆环上，大圆环垂直地嵌入水平大圈的两个缺口内，下面四根雕有龙头的立柱支撑着水平大圈，托着整个天体仪。

We call this sphere the celestial sphere.

" 这个球面我们叫做"天球。

This article Proof of the double-filled sphere between the two media point charge of the distribution of electric potential.

本篇文章推证了在双层球面间填充两种介质的点电荷产生的电势分布规律。

Corrected for both chromatic and spherical aberration, as a lens.

复消色差的矫正色相差和球面像差的，如镜头

And chrome steel bearing, plastic ball bearing unit of all kinds of materials

另有铬钢轴承(Gcr15)，及各种材料的带座外球面轴承。

Core adjusting rolling bearing type 22300 has 2rows of symmetry rolling spherical and copper alloy suppting frame,there is no fixed circlip in inner circle,the roller is the longer type,it has the abillity to support more load,the circlip will lead while moving,it has the better performance of core adjusting,also it can compensate the tolerance of coaxiai degree.

调心滚子轴承22300CA型具有两列对称球面滚子和铜合金实体保持架，内圈无固定挡边，滚子加长，承载能力大，活动中挡圈由内圈引导，调心性能良好，能补尝同轴度误差。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。