波动力学

Theobserved strain is 10~2 times as local point strain at the same observed stress.This indicates that macroscopical symmetrical rock is quasi-brittle materialwith microcosmic heterogeneousness and its macroscopical mechanicalbehavior is the results of reciprocity and magnification between microcosmiccharacteristic, not simple sum.(4) The degree of irregularity of strain increases with the number of cycle.But degree of irregularity of transverse strain fluctuates larger at the samecycle. Moreover degree of irregularity of transverse strain is larger than that ofaxial strain. This shows that deformation and failure of rock is process ofevolvement of small crack. Small crack evolves from even and out-of-orderstatus to heterogeneous and ordinal status.(5) Ultrasonic speed decreases with the number of cycle. The decreasecourse is such: Firstly, ultrasonic speed fluctuates in a steady scope in somecycles; And then ultrasonic speed quickly decreases to a certain more smallvalue; Afterwards in succedent cycles, ultrasonic speed fluctuates about thevalue. That is to say, ultrasonic speed fluctuates and decreases at intervals ofcycles. In deformation process of rock, quantitative change and qualitativechange of its small crack evolvement carry through crosswise.(6) Strength and modulus of rock decrease with exponential function asscale of specimens increases.

同一表观应力下，局部点应变与表观应变相差可达2个数量级，表明宏观上均匀的岩石是具有细观特征的准脆性材料，其宏观力学行为是细观特征相互作用、放大的综合结果，而不是简单的叠加；(4)岩样轴向应变不均匀程度和横向应变不均匀程度随循环次数的增加渐进增大，但是在同一个循环内，横向应变离散系数随应力的变化波动较大，且同一循环级别下，横向应变不均匀程度大于轴向应变不均匀程度，表明岩石内部微裂纹的演化是岩石变形破坏的本质特征，这一演化表现为微裂纹从均匀无序分布逐渐向非均匀有序发展；(5)随循环次数的增加，所有岩样内部超声波速会出现衰减，衰减过程表现为在某几次循环内超声波速在某一相对范围内波动，然后急剧减小到某一较小值，在随后的循环内，超声波速又会保持在这一较小值附近波动，即超声波速表现为波动和急剧减小间隔形式衰减，表明从宏观看来平稳的岩石变形过程，内部结构演化过程(微裂纹发展及其相互作用)却表现为均匀量变和突发质变不断交叉进行的现象；(6)岩石强度和弹性模量随尺度增大呈指数函数规律减小。

Using the powerful calculation capability of MATLAB for matrix,and adopting vector ring and vector chain equation,the paper calculates and imitates the characteristic of kinematics and kinetics about equivalent force model of plane machinery.

利用MATLAB软件对矩阵强大的计算能力，采用矢量环与矢量链方程对平面机构的等效力学模型的运动学特性和动力学特性进行计算仿真，主要针对机构的速度波动特性进行了仿真和分析。

Contents include: Newtonian mechanics and relativity based, thermal and mechanical vibration, and wave, electromagnetic wave optics and quantum physics foundation etc.

内容包括：牛顿力学及狭义相对论力学基础、热学、电磁学、振动与波动、波动光学和量子物理学基础等。

It is because of the mechanical behavior that the counter bearing pressure at the driving side of a mixing drum driven by a large-scale rubber tyre is not even and excessive ,which brings the elastic distortion to the tyre.

大型橡胶轮胎传动的圆筒混合机由于力学行为造成传动侧支反力不均且过大，使轮胎发生弹性变形，增大了弹性阻力矩，使电流波动过大，减速机经常磨损、胶合，导致轮胎磨损严重而停产。

This paper analyses mechanics property of horizontal press winding adopted on warping machine, develops the law of warp beam pressure and puts forward the way to reduce the motion between the roller and warp beam.

分析了整经机水平轨道式加压卷绕机构的力学特性，通过计算得出了经轴正压力的变化规律，提出了降低滚筒与经轴间压力最大波动幅度的措施。

Linearized theory of wave phenomena in applied mechanics.

应用力学里波动现象的线性理论。

ABSTRACT Impact machines operating by mechanical impact, which have been of very long history, play still an important role in modern industry. In shis paper, the following essential subjects of impact mechanism are systematically studied based on wave mechanics.

冲击机械具有悠久的历史，并在现代生产行业中占据着相当重要的地位，本文从冲击机械的共性出发，应用波动力学理论，较系统地研究了冲击机械原理和设计中的一些基本问题。

In the process of impact of abrasive jet on rock, resulting dynamic stress plays an important role in rock destruction. The stress wave resulted makes local rock tensile and shearing, then makes rock destructed. In the conditions of some hypotheses, the mechanical model that rock is applied by stress wave, i.e. jet wave basic equations, are set up by wave theory, and the formula of the maximum normal stress resulted by stress wave is deduced according to known boundary conditions.

描述了岩石材料在磨料射流的冲击下破坏的主要原因，分析了应力波就是岩石局部受到拉伸和剪切并最终使岩石发生破坏的根本因素，在这一假设的前提下采用波动理论建立了岩石受应力波作用的力学模型即射流波动的基本方程，在已知的边界条件下推导出了由波动引起的最大正应力的计算公式。

The rock-crushing process of dynamic impacting load is simplified, By means of elastic mechanics and wave theory , the axial force and shearing force of ro.

以弹性力学、波动理论和冲击动力学为基础，采用室内试验和力学理论相结合的研究方法，建立了旋冲钻井破岩力学模型。

When the velocity proportion of longitudinal wave to transverse wave of a bed is distinctly different from that of another bed, the reflection factor will be changed with the variation of incident angle according to the elastic wave mechanics, which is the foundation of AVO theory.

由弹性波动力学理论可知，当一种岩层纵、横波速度与另一种岩层纵、横波速度之比明显不同时，反射系数随入射角的变化而变化。

Cynanchum Lingtai apricot production in the average weight 65 grams, the brightly-colored fruit, juicy rich, sweet-sour taste, sweet from the nucleolus, when the late Qing Dynasty famous Shaanxi, Gansu provinces, the Qing imperial court Tongzhi tribute for years.

灵台生产的牛心杏平均单果重65克，果实色泽鲜艳，汁多味浓，甜酸适口，离核仁甜，清末时就驰名陕、甘两省，清同治年间曾为朝廷贡品。

Chenopodium album,Solanum nigrum, and Amaranthus retroflexus were very susceptible to the herbicides. Polygonum persicaria and Abutilon theophrasti were relatively less susceptible to the herbicides, and Lycopersicon esculentum was not susceptible to it. The relationship between reduction rates of weed biomass and PPM values of weed leaves 2,4, and 6 days after treatment was established.

供试的6种杂草对该混剂的敏感性存在显著差异：红心藜Chenopodium album、龙葵Solanum nigrum和反枝苋Amaranthus retroflexus对该混剂最敏感，ED90值分别为47.65、71.67和29.17g/hm2；春蓼Polygonum persicaria和苘麻Abutilon theophrasti敏感，ED90值分别为96.91、114.20g/hm2；而番茄不敏感。