力学

After the birth of celestial mechanics to become a sub-discipline of celestial mechanics.

天体力学诞生以后，成为天体力学的一个次级学科。

Based on the theory and method of classical celestial mechanics and orbit dynamics of the artificial earth satellite, we need not to start the research from the every beginning.

经典天体力学和人造地球卫星轨道力学都形成了完整的理论体系与研究方法。

This course introduces basic knowledge of Analytical Mechanics and theory of movement stability, and focuses on dynamics knowledge related tightly with engineering technique such as orbit moment in central gravitation field, electromechanical coupling dynamics, rigid-body dynamics, gyroscopic dynamics, manipulator dynamics et al.

本课程较系统地叙述了分析力学和运动稳定性理论的基础知识，着重介绍与工程技术密切相关的动力学知识，如中心引力场中的轨道运动、机电耦合系统动力学、刚体动力学与陀螺力学、机械臂的动力学分析方法。

EXPERIMENTAL STUDY ON THE INFLUENCE OF PROCESSING ON THE MECHANICAL PROPERTIES OF ENGINEERING CERAMICS Fan Ning Ai Xing Deng Jianxing Wang Yixing (Shandong University of Technology) Abrstract The mechanical properties of engineering ceramic are impacted by itself and its surface status.

加工方法对工程陶瓷力的影响摘要工程陶瓷的力学性能受材料本体和表面状况的共同影响。加工方法对材料的表面状况有较大的影响，因此，陶瓷材料的力学性能也受加工方法的影响深圳陶瓷加工工业陶瓷加工

Based on the foregoing analysis, the critical condition of realizing ductile/brittle transform is confirmed, and then, the model of ductile grinding of engineering ceramic is built.

以陶瓷材料压痕断裂力学、线性断裂力学和微观断裂物理学为理论基础，系统的分析和讨论了磨削加工过程中微裂纹的产生机理及其影响因素，建立了裂纹分布模型，并根据位错产生微裂纹机制，对磨削过程微裂纹的形成采用位错塞积模型来描述，从能量平衡的角度，讨论位错裂纹的稳定性与磨削应力的关系，确定了材料脆性去除和塑性去除转换的临界条件，最终建立以此为基础的工程陶瓷材料延性域去除模型。

The results show that the shrinkage temperature of the leather tanned with QUIMITAN ABC is 101.4℃, and the physical-mechanical properties of QUIMITAN ABC tanning leather are better than that of chrome powder tanning leather; the content of Cr2O3 (0.4142 g/L) in the float of QUIMITAN ABC tanning is lower than that of the content of Cr2O3 (1.9481 g/L) chrome powder tanning, it's clear that QUIMITAN ABC tanning is good for Cleaner production; under the same content of chromic oxide, the physical properties of retanning leather with QUIMITAN ABC are better than that of retanning leather with chrome containing sytan and chrome powder, such as thichkening, flexibility, physical-mechanical properties.

结果表明：QUIMITAN ABC主鞣后的坯革的收缩温度为101.4℃，且其坯革物理力学性能高于用6%的铬粉主鞣后的坯革；QUIMITAN ABC主鞣后的废液Cr2O3含量(0.4142 g/L)明显低于用6%的铬粉主鞣后废液Cr2O3含量(1.9481 g/L)，用QUIMITAN ABC主鞣有益于清洁化生产；在Cr2O3含量相同的情况下，用QUIMITAN ABC复鞣的坯革在增厚率、柔软度、物理力学性能等方面都要好于含铬鞣剂及铬粉复鞣的坯革。

Special solutions for the ring circular domain with crack surfaces acted on uniform compressive force, linear compressive force and linear shearing force are deduced in polar coordinate employed the eigenfunction expansion technique in the Hamiltonian system of elastic mechanics. Combined with the general solution for the above problems, the analytical solutions for crack tip fields with surfaces acted on the above three kinds of loads are obtained. These solutions offer theoretical basis to construct analytical elements for plastic analysis of crack.

从弹性力学哈密顿体系理论出发，利用平面弹性力学极坐标系下的本征向量展开求解，推导了环形圆形域裂纹边作用有均布压力、线性压力和均布剪切力情况下的特解，从而得到了裂纹表面作用有以上三种荷载情况下的裂纹尖端场的解析解，为进一步构造进行弹塑性裂纹分析的奇异解析元奠定了理论基础。

Postulates of classical statistical mechanics, micro canonical, canonical, and grand canonical distributions; applications to lattice vibrations, ideal gas, photon gas.

经典统计力学的假定、微正则、正则和巨正则分布；统计力学在晶格振动中的应用、理想气体、光子气体。

The relationship with a coefficient of determination of 0.7214 is found between the mechanical properties and the degree of mechanical damage of tomato. The peak force has the most significant relationship with the degree of mechanical damage.

番茄的机械损伤度与力学参数之间的回归系数为0.7214，其中与番茄机械损伤度最相关的力学参数是峰值力。

We've found that on symplectic manifolds there exists a series of Euler-Lagrange cohomology groups different from both de Rham and harmonic cohomology in general and proposed a set of general volume-preserving equations that contain the Hamiltonian equations as a special case.

中文摘要：我们发现在作为经典力学中的相空间的辛流形上有可能存在不同于de Rham上同调和调和形式的上同调，称之为Euler-Lagrange上同调；提出相空间上保体积的一般方程，通常的正则方程是其特殊形式；进而推广了经典力学中著名的刘维定理；同时把Noether定理与上同调联系起来。

I will endeavour to find you some assistance.

我尽力帮你找人帮忙。

At first I only know bruck is the idol of American younglings, afterwards I returned back to Taiwan ,even in Beijing last year ,I saw her poster everywhere, I was so surprised at her charm.

起初我只晓得布鲁克雷德丝是美国少男少女崇拜的偶像，后来回台湾，甚至去年在北京，居然也四处看见她的海报，才惊讶她的魅力之大。