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41901对于生产难以控制，易出不合格产品，或因堵、漏常常停产检修的生产装置，生产时数一般采用（），甚至更少。
41902物料衡算可分为单元操作过程和全流程的两类物料衡算，分类依据是（）
41903物料平衡是指（）
41904物料平衡的理论依据是（）。
41905管道仪表流程图需按比例绘制。（）
41906提馏段指标控制方案适用于以塔釜液为主要产品的精馏塔操作。（）
41907精馏段指标控制方案适用于以塔底馏出液为主要产品的精馏塔操作。（）
41908换热器的温度控制可通过以下哪些途径实现？
41909泵输送流体的流量控制有哪几种方案？（）
41910PCD图是指（）
41911PFD图是指（）
41912施工图设计阶段的PFD图要求列出全部设备包括备用设备并标注其位号。（）
41913按设计阶段的不同，工艺流程设计按先后顺序分为：方框流程图、工艺流程草图、管道仪表流程图、工艺物料流程图等四个阶段。（）
41914管道组合号由4部分组成，包括（）
41915工艺流程设计的原则包括（）
41916选取工艺流程时的步骤包括：a.调查研究、搜集资料b.全面比较与确定c.落实关键设备d.治理三废、消除污染。以下排序正确的是（）
41917PID是以下哪种工艺流程图的简称？
41918工艺物料流程图主要反映化工计算结果，它表达了一个生产过程中的全部设备、全部节点的物料性质、流量及组成。（）
41919各个阶段工艺流程设计的成果都是通过各种流程图和表格表达出来，按照设计阶段的不同，先后有（）
41920工艺流程设计的主要任务有两个（）
41921工艺流程设计应遵循以下原则（）
41922工艺路线的选择原则有（）
41923以下常用设备类别代号对应错误的是（）
41924以下工艺物料代号对应错误的是（）
41925PFD是（）的简称。
41926PID是（）的简称。
41927Cementite is much harder but more brittle than ferrite.
41928Martensite will appear on the iron-iron carbide phase diagram.
41929In the iron-carbide phase diagram, when at the temperatures above the eutectoid and for all times, only austenite will exist.
41930Temperature plays an important role in the rate of the austenite-to-pearlite transformation.
41931The first process to accompany a phase transformation is nucleation.
41932δ-ferrite is stable only at relatively high temperatures.
41933In practice, not all steels and case irons have carbon contents less than 6.7 wt% C.
41934α iron has a BCC crystal structure.
41935Of all binary alloy systems, the one that is possibly the most important is that for iron and carbon.
41936For all temperatures and compositions below the melting temperature of the lowest melting component, only a single solid phase will exist.
41937We don’t have to employ the tie line if two phases are present.
41938From the previous example for the 60 wt%Ni-40 wt% Cu alloy at 1100℃, only the α phase is present.
41939When two phases are present in a system, it is necessary that there will be a difference in both physical and chemical properties.
41940Sugar-water syrup solution and solid sugar are different phases.
41941Every pure material is considered to be a phase.
41942The microstructure that develops in iron-carbon alloys depends on（）.
41943The form of iron-carbon phase can be divided into（）.
41944For a binary system of known composition and temperature, that is at equilibrium, at least three kinds of information are available.
41945自由能主要由哪些因素决定？
41946贝氏体的微观结构由（）和（）组成。
41947The thickness ratio of the ferrite and cementite layers in pearlite is approximately（）.
41948The time necessary for the transformation to begin and then end depends on（）.
41949The maximum solubility of carbon in austenite, 2.14 wt%, occurs at（）℃.
41950In the BCC α ferrite, the maximum solubility is（）wt% at 727℃.
41951We can find（）single-phase regions in the copper-silver diagram.
41952The first step in the determination of phase compositions is to（）.
41953Possibly the easiest type of binary phase diagram to understand and interpret is that which is characterized by the（）system.
41954What is helpful in predicting phase transformation?
41955During plastic deformation, slip or dislocation motion may not take place across a common grain boundary.
41956The grain boundaries usually do not come apart or open up.
41957For a screw, the dislocation line motion is parallel to the stress direction.
41958A screw dislocation may be thought of as resulting from shear distortion.
41959Plastic deformation is permanent.
41960High yield strength is beneficial to material cold forming and welding performance improvement.
41961The combination of the slip plane and the slip direction is called the slip system. The less the slip system, the better the plasticity of the metal.
41962重结晶过程中，力学性能会发生什么改变?
41963金属的位错密度会被以下哪些影响?
41964金属颗粒尺寸可能对下列哪些物质有影响?
41965随着晶核生长，所有的晶界区域会（）。
41966晶核生长必须有以下哪些步骤?
41967纯金属重结晶过程相比于合金重结晶过程会（）。
41968当杂质原子出现时，对滑移的抵抗力会（）。
41969哪种晶界能有效阻止滑移并且增加材料强度?
41970以下哪个是增强技术遵循的准则?
41971形变强化是材料的一种特性， 是（）阶段产生的现象。
41972The stress distribution on the notch section is uniform.
41973The internal force concentration caused by internal force is called stress.
41974常用的塑性判断依据是（）。
41975金属疲劳的判断依据是（）。
41976对于脆性材料,其抗压强度一般比抗拉强度（）。
41977韧度是衡量材料韧性大小的力学性能指标，是指材料断裂前吸收（）的能力。
41978Solid-state diffusion is a means of mass transport within solid materials by stepwise atomic motion.
41979扩散系数只取决于晶体结构。
41980Nonsteady-state diffusion means that the diffusion particle concentration distribution does not change with time.
41981空位扩散的速度要快于填隙扩散的速度。
41982The vacancy is in the same direction as the atom.
41983扩散系数与哪些因素有关？
41984扩散机理可分为哪些？
41985What are the factors that influence the diffusion?
41986渗碳层中碳浓度分布函数是？
41987在菲克第一定律中D 的含义是什么？
41988刃型位错的位错线不一定是直线。
41989螺型位错位错线垂直于伯格斯矢量。
41990杂质原子加入金属中将会导致形成固溶体或者第二相。
41991Defects do occur alone.
41992晶体都呈现电中性。
41993所有晶体都包含缺陷。
41994Which of the following statement is correct.
41995Which of the following statements about dislocation are correct.
41996下列属于热缺陷的有：
41997Which of the following statements about solid solutions are correct.
41998空位平衡浓度与哪些因素有关？
41999点缺陷包含的类型
42000Which of the following statement about the Burgers vector is incorrect.
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