第二章传热过程 第一节传热基本舰殚 热量衡算 传热速率Q(W) Q2=Q3 、传导传热

第一章课堂练习题解 1.空间有一均匀带电球壳,带电量为Q(不是导体球), 假定固定它的电荷分布是均匀的,在球壳外放置一点电荷-Q (设Q不改变球壳的电荷分布),画出电力线分布

采用每道次挤压后样品旋转90°进入下一道次且旋转方向不变方式(Bc)的等径弯曲通道变形(ECAP)工艺制备亚微晶Q235钢,并研究了4个面不同的组织演化．研究表明,ECAP变形Q235钢的组织随变形道次的增加而细化,其中第1道次的细化程度最大．4个面的形貌也不同:S面以位错胞为主;R面在第2道次出现变形带交叉现象;而T面2道次就有近似的等轴胞出现,4道次出现了晶界很清楚的等轴晶,尺寸为0．25μm左右;L面4道次后也有等轴晶出现,但晶界没有T面4道次的晶界清楚．8道次后所有的面都已经演化成晶界清晰的等轴晶,尺寸为0．2μm左右．采用ECAP变形可以获得亚微晶Q235钢．

Experiments show that a charged particle moving in a magnetic field experiences a force F=Q(v×B) Q-the charge of the particle, v-the velocity of the particle(vector), B-the magnetic field. there is also an electric field, the force acting on the particle is F=Q(E+v×B)

European Options on Stock 12.2 Paying Continuous Dividends We get the same probability distribution for the stock price at time T in each of the following cases 1. The stock starts at price So and provides a continuous dividend yield q 2. The stock starts at price Soe-q' and provides no dividend yield

Application of MR2T2 algorithm in statistical mechanics Canonical ensemble: Distribution function: p(rN)=exp(-E(rN)/KT)/Q Q= JdrN exp(-E(rN)/kT) Different states of the Markov chain: In the application of Metropolis algorithm to a simulation of molecular system, the states of the Markov chain correspond to different configurations of the molecular system

地下水的运动 渗流 过水断面A (a) (b) 图59地下水在土层孔隙中的流动 (a)一水流实际流线;(b)一水流虚构流线 渗透流速=Q/A 实际流速u=Q/A’V