圆盘的

In this sharp composite from the Hubble Space Telescope, Fomalhaut's surrounding ring of dusty debris is imaged in detail, with overwhelming glare from the star masked by an occulting disk in the camera's coronagraph.

在这幅来自哈勃空间望远镜的精细合成图像中，北落师门周围的尘埃环的碎片能够精细展现，并且在相机的日冕观测仪下，能够观测到被一神秘圆盘遮蔽的恒星发出十分耀眼的光线。

In this paper we define the concept of Projective Blaschke manifolds and extend the theory of equiaffine differential geometry to the projective Blaschke manifolds. We prved that if M be a complete projective Blaschke n-sphere and its universal covering manifold is isometric to a complete (n+1) dimensional parabolic, elliptic or hyperbolic affine hypersphere, then M is a quotient space of E^n, S^n or D^n by a isometric subgroup of its corresponding spaces.

在这篇文章中我们定义了射影Blaschke流形的概念，将等仿射微分几何的理论推广到了射影Blaschke流形，并证明：如果n维完备射影Blaschke 超球面 M 的通用覆盖流形分别是完备的抛物型、椭圆型或双曲型仿射球，则M分别是n维欧氏空间、n维超球面或n维单位圆盘关于各自空间的一个等距离散子群的商，从而对完备射影Blaschke 超球面进行了分类。

Then the finite element software ANSYS is used to simulate the orthotropic flattened Brazilian disc specimen subjected to diametrical compression, the accuracy of the approximate formula of compression displacement is checked. The formula is further modified with a semi-empirical and semi-analytical approach, and it is shown to have better accuracy than the original formula covering the whole range of orthotropic anisotropic index of rock, the error is less than 6%.

用有限元分析软件ANSYS模拟正交异性岩石的巴西圆盘试样的对径压缩实验；利用有限元分析结果对正交异性平台位移压缩公式进行精度检验，并用半经验半解析的方法，对该公式进行局部的修改，修改后的公式在岩石材料的正交异性指数的整个范围的总体评价上，误差小于6%，具有更好的计算精度。

The stability problem leads to an ordinary differen-tial equation containing three parameters representing partialderivatives of a phase function.

一个非定常流动的稳定性问题被归结为求解三个未知函数为参数的微分方程的特征值，其三个参数分别是非线性扰动波的相函数的导数及圆盘运动速度的函数。

The thermodynamics and the dynamics mechanism have been studied.The results show that it is advisable for the HCHO and NaH_2PO_2 as the reduction due to the electrode potential of the reduction is more negative than that of Cu~ 2+ from the analysis of data in thermodynamics.It is advantage for the reaction of electroless copper in the alkaline solution. According to the analysis of Tafel slope of a cathodal polarization curve,...

结果表明：从热力学数据分析看，还原剂的电极电位皆比铜离子负，用甲醛、次亚磷酸钠做还原剂还原Cu2+在热力学上是可行的，在碱性溶液中对化学镀铜反应有利；从阴极极化曲线的Tafel斜率分析看，Cu2+=Cu+步骤为阴极反应的速度控制环节；从镀液的旋转圆盘电极测试结果分析看，电子跃迁步骤H2CO-ad rdsHCOOH+1/2H2+e-为镀液中阳极反应速度的控制性步骤。

The paper establishes an appropriate model of vibration system composed of horn and gear. The transmission of ultrasonic is changed from longitude wave into transverse wave; the gear vibrates in flections mood and obtain larger vibration displacement in the grinding region.

本文提出了一个适用的振动系统模型，由变幅杆和齿轮组成一个复合振动系统，将超声波的传递方式，由纵波变为横波，齿轮作圆盘弯曲振动，使齿轮的磨削区域得到较大的振动位移。

In order to accommodate the pickling line and tandem cold mill unit with diversification of the production rhythm,loopers are equipped between welders and tension levelers,between acid tanks and side trimmers and at the entry of the tandem cold mill to store the strip and keep the pickling speed stable.

0前言随着下游产品和后道工序针对冷轧钢板表面质量和内在性能要求的不断提高，在冷轧的酸洗轧机联合机组中，无论正常的生产节奏如何变化，都希望能够做到带钢表面酸洗的连续、稳定、恒速，为了达到这一目的，在焊机和拉矫机之间、酸槽和圆盘剪之间以及轧机入口，分别设置了用于储存带钢的活套装置。

Soft-finned mainly freshwater fishes typically having toothless jaws and ''.

软鳍的主要是淡水的鱼，特征是生有无牙的咽喉和圆盘状的鱼鳞。

Soft-finned mainly freshwater fishes typically having toothless jaws and cycloid scales.

软鳍的主要是淡水的鱼，特征是生有无牙的咽喉和圆盘状的鱼鳞。

Wu: The domestic mining industry begins to realize the necessary of the modern exploit equipment such as wire saw machine and high-speed rock driller. But there are quite a lot of quarry owners without scientific exploiting way. For example, some of them used cutting disc to mine the marble and granite which without better integrality. As a result, they have wasted much time and fund.

吴：国内采石矿业逐渐意识到使用金刚石绳锯机、高速凿岩钻机等现代化开采装备的必要性，但仍有相当多的矿主没有清晰的开采思路，比如有些矿主使用圆盘锯开采大理石或完整性不好的花岗石矿山，结果是浪费了很多时间和资金。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。