化工专业英语复习资料2014.doc

transient瞬时的 assumed假设的 boundary边界 uniform相同的，恒定的value 值 boiling 沸腾 surface 表面 sub-cooled 过冷的 significant显著的mechanisms机理 moisture潮湿 condensate冷凝 contact接触efficient有效率的 batch 间歇的 continuous 连续的local局部 latent 潜在的 fractionating column 精馏柱capacity容量 distributions分布 aging老化 pickling酸洗 amorphous无定形的 hold 保留，控制 Silica gel 硅胶 hydrocarbons 碳氢化合物equilibrium 平衡 subsystems子系统，次级系统fundamental principles基本原理evaporation蒸发black body黑体empty space 真空区concentration浓缩visible light可见光radiation 辐射distillate 馏出液acetonitrile 已腈precipitation 沉淀cation 阳离子hydroxide 氢氧化物chromatography层析recrystallization 重结晶sublimation 升华physisorption 物理吸附activated carbon 活性炭hydrophilic 亲水性heat exchanger换热器用英文解释下列单词含义（自己在课件中找）Heat transfer:传热Heat exchanger：换热器Precipitation：沉淀Separation process：分离过程Dropwise condensation：液滴冷凝Steady state conduction：稳态传导Forced convection：强制对流A fractionating column：精馏塔Distillation：蒸馏Raoults law：拉乌尔定律Filmwise condensation：薄膜冷凝Tube Layout：管布局Waste heat recovery units：余热回收装置Laboratory fractionating columns：实验室用精馏柱Daltons law：道尔顿定律Continuous distillation：连续蒸馏Freeze drying：冷冻干燥Heat Conduction: 热传导Natural convection：自然对流Heat Radiation：热辐射翻译（自己翻译）1. Historically, the different chemical industries were regarded as different industrial processes and with different principles. In 1923 William H. Walker, Warren K. Lewis and William H. McAdams wrote the book The Principles of Chemical Engineering and explained the variety of chemical industries have processes which follow the same physical laws. They summed-up these similar processes into unit operations. Each unit operation follows (遵循）the same physical laws and may be used in all chemical industries. The unit operations form the fundamental principles of chemical engineering.从历史上看，不同的化学工业被视为不同的工业流程和不同的原则。威廉.H.沃克，沃伦.K.刘易斯和威廉.H.麦克亚当斯在1923年写这本书，化工原理，并解释说，化工等行业的各种过程，遵循相同的物理定律，可用于所有的化学工业。化工单元操作构成了化工系统的基本原则。2. For thermo economic optimization it is suggested that the baffles be spaced no closer than 20% of the shells inner diameter. Having baffles spaced too closely causes a greater pressure drop because of flow redirection. Consequently having the baffles spaced too far apart means that there may be cooler spots in the corners between baffles. It is also important to ensure the baffles are spaced close enough that the tubes do not sag. The other main type of baffle is the disc and donut baffle which consists of two concentric baffles, the outer wider baffle looks like a donut, whilst the inner baffle is shaped as a disk. This type of baffle forces the fluid to pass around each side of the disk then through the donut baffle generating a different type of fluid flow.热经济优化建议的挡板间隔不超过壳的内直径近20%。在挡板间隔过于紧密，导致更大的压力，因为流量重定向下降。因此有挡板间隔太远，有可能是凉点挡板之间的角落。这也是确保挡板的间距足够接近，管不凹陷重要。其他主要类型的挡板是圆盘和圆环挡板由两个同心的挡板，挡板外广泛看起来像一个甜甜圈，而内挡板的形状为圆盘。这种类型的挡板，迫使流体通过在每个磁盘的一面，然后通过圆环挡板产生不同类型的流体流动。3. Natural convection is when the fluid motion is caused by buoyancy forcesthat result from the density variations due to variations of temperature in the fluid. For example in the absence of an external source, when the mass of the fluid is in contact with a hot surface its molecules separate and scatter (分散)causing the mass of fluid to become less dense. When this happens, the fluid is displaced vertically or horizontally while the cooler fluid gets denser and the fluid sinks. Thus the hotter volume transfers heat towards the cooler volume of that fluid.自然对流发生在由于浮力引起的流体运动，这种浮力变化是流体中由于密度变化而引起温度变化的结果。例如在外部源的情况下，当流体聚集态与热源接触时，其分子发生分离并分散造成流体质量密度变小。热流体对冷流体就发生传热。4、Fractional distillation is one of the unit operations of chemical engineering. Fractionating columns are widely used in the chemical process industries where large quantities of liquids have to be distilled. Such industries are the petroleum processing, petrochemical production, natural gas processing, coal tar processing, brewing liquified air separation, and hydrocarbon solvents production and similar industries but it finds its widest application in petroleum refineries . In such refineries, the crude oil feedstock is a very complex multicomponent mixture that must be separated and yields of pure chemical compounds are not expected, only groups of compounds within a relatively small range of boiling points, also called fractions and that is the origin of the name fractional distillation or fractionation. It is often not worthwhile separating the components in these fractions any further based on product requirements and economics. 精馏是化学工程的单元操作之一。被广泛应用于使用大量的液体蒸馏分馏塔的化学加工工业中。这些行业包括石油加工、石化产品、天然气加工、焦油(煤焦油)生产加工、酿造、液化空气分离和烃类溶剂生产等类似行业，但它使用最广泛的还是石油精炼。在炼油厂，原油原料是一个非常复杂的多组分混合物，必须分离和纯化学化合物的产量不是预期的，在一个相对较小的沸点范围的化合物组，也被称为组分，是名字的蒸馏或分馏的起源。它往往是不值得在这些分数的任何进一步的基于产品的要求和经济分离的组件。5、A heat exchanger is a device built for efficient heat transfer from one fluid to another, whether the fluids are separated by a solid wall so that they never mix, or the fluids are directly contacted. Heat exchangers are widely used in refrigeration, air conditioning, space heating, power generation, and chemical processing. One common example of a heat exchanger is the radiator(水箱) in a car, in which the hot radiator fluid is cooled by the flow of air over the radiator surface.换热器是一种有效地将两种流体进行热交换的装置，这两种流体是被固体壁垒隔开，避免两者混合，或者直接接触。换热器广泛应用于冷却、空调、供暖、发电、化学处理。关于换热器，常见的例子是在汽车的散热器（水箱），其中水箱中的液体通过在散热器表面的空气流冷却。 6、As a liquid mixture in the round bottomed flask is boiled, vapor rises up the fractionating column. The vapor condenses on the glass platforms (known as trays or plates) inside the column, and runs back down into the liquid below and refluxes the upflowing distillate vapor. The hottest tray(塔板) is at the bottom of the column and the coolest tray is at the top. At steady state conditions, the vapor and liquid on each tray is at equilibrium. Only the most volatile of the vapors stays in gas form all the way to the top. The vapor at the top of the column then flows through the water-cooled condenser, which cools the vapor down until it condenses into a liquid distillate. The separation may be enhanced by the addition of more trays (to a practical limitation of heat, flow, etc.). 当圆底烧瓶中的混合物煮沸，蒸气上升至分馏塔。塔内玻璃板上的水汽凝结（称为托盘或塔板），并回落到下面的液体与上升的蒸气逆流交汇。最热的塔板在塔底和最冷的塔板在塔顶。在稳态条件下，每块塔板上的水汽和液体达到平衡。最易挥发的蒸气停留塔顶形成一路气体。在塔顶部的蒸气，然后经水冷式冷凝器，这个过程中蒸气冷却下来，凝结成液体馏分。此外增加塔板数，可增强分离效果（实际限制了热量、流量等）。7. Portal site mediated adsorption is a model for site-selective activated gas adsorption in metallic catalytic systems which contain a variety of different adsorption sites. In such systems, low-coordination “edge and corner” defect-like sites can exhibit significantly lower adsorption enthalpies热焓 than high-coordination (basal plane) sites. As a result, these sites can serve as “portals” for very rapid adsorption to the rest of the surface. The phenomenon relies on the common “spillover溢出的” effect (described below), where certain adsorbed species exhibit high mobility on some surfaces. The model explains seemingly inconsistent不一致 observations of gas adsorption thermodynamics and kinetics in catalytic systems where surfaces can exist in a range of coordination structures, and it has been successfully applied to bimetallic catalytic systems where synergistic activity is observed.8.The closed system design required for achieving and maintaining the low-pressure atmosphere inside the dryer also provides advantages for processing a hazardous material. Examples include toxic chemicals or solvents and explosive materials. The vacuum dryer safely contains and condenses the hazardous vapors from such substances without any threat to your workplace environment or outside atmosphere. With some hazardous materials, you can provide further protection by using inert gas to limit the oxygen level in the vacuum dryer.封闭系统的设计要求实现和保持干燥器内的低压气氛，也利于处理有害物质。例如有毒化学品或溶剂以及易爆物品。真空干燥剂应在不影响自身工作环境的情况下安全地控制和凝结有毒物质的蒸气。在有害物质存在的情况下，可以利用惰性气体提供进一步的保护，以限制在真空干燥器中的氧含量。9. In microcentrifugation, centrifuges are run in batch to isolate small volumes of biological molecules or cells (prokaryotic原核的 and eukaryotic真核的). Nuclei核子 is also often purified via microcentrifugation. Microcentrifuge tubes generally hold 1.5-2 mL of liquid, and are spun旋转 at maximum angular speeds角速度of 12000-13000 rpms. Microcentrifuges are small and have rotors that can quickly change speeds. Superspeed centrifuges work similarly to microcentrifuges, but are conducted via larger scale processes. Superspeed centrifuges are also used for purifying cells and nuclei, but in larger quantities. These centrifuges are used to purify 25-30 mL of solution within a tube. Additionally, larger centrifuges also reach higher angular velocities (around 30000 rpm) and also use a larger rotor转子.10. Radiation is the transfer of heat energy through empty space. All objects with a temperature above absolute zero radiate energy at a rate equal to their emissivity multiplied by the rate at which energy would radiate from them if they were a black body. No medium is necessary for radiation to occur, for it is transferred through electromagnetic waves; radiation works even in and through a perfect vaccum. The energy from the Sun travels through the vacuum of space before warming the earth. 热辐射是指热能通过真空传递的一种方式。所有温度高于绝对零度的物体，其热辐射速率等于其发射率乘以黑体辐射常熟。辐射必须发生在无介质的场所中，因为它是通过电磁波传递的；甚至可以发生在绝对真空中。如太阳能在传播至地球之前，就首先通过真空传播。11. Such industrial fractionating towers are also used in air separation, producing liquid oxygen, liquid nitrogen, and high purity argon. Distillation of chlorosilanes氯硅烷 also enables the production of high-purity silicon硅 for use as a semiconductor半导体.Design and operation of a distillation tower depends on the feed and desired products. Given a simple, binary component feed, analytical methods such as the McCabe-Thiele method or the Fenske equation can be used. For a multi-component feed, simulation models are used both for design and operation. Moreover, the efficiencies of the vapor-liquid contact devices (referred to as plates or trays) used in distillation towers are typically lower than that of a theoretical 100% efficient equilibrium stage. Hence, a distillation tower needs more trays than the number of theoretical vapor-liquid equilibrium stages.12. Here vacuum drying provides a unique advantage. By controlling atmospheric pressure, the vacuum dryer increases the effective T for a given process. That is, vacuum drying simple reduces the boiling point - or vaporization temperature - required for removing the liquid. By controlling pressure and the heat introduced to the dryer, you can significantly increase the effective T and thus dry the material faster than at normal atmosphere. For this reason, a vacuum dryer is especially suited to drying a heat-sensitive material that degrades above a given temperature and would otherwise require a lengthy drying cycle. Examples of such materials are vitamins, antibiotics, and many fine chemicals.真空干燥提供了一个独特的优势。通过控制大气压力，真空干燥可以为给定过程增加有效的T。也就是说，真空干燥可以降低沸点-或汽化温度-来去除液体。通过控制压力和干燥器的加热量，可以显著增加有效温差，从而使得物料的干燥速度比常压快。出于这个原因，真空干燥，特别适合干燥热敏性的物料，这种物质在高于给定的温度会降解，否则将需要漫长的干燥周期。比如维生素、抗生素、许多精细化学品。13. Separation processes can essentially be termed as mass transfer processes. The classification can be based on the means of separation, mechanical or chemical. The choice of separation depends on the pros and cons of each. Mechanical separations are usually favored if possible due to the lower cost of the operations as compared to chemical separations. Systems that can not be separated by purely mechanical means (e.g. crude oil), chemical separation is the remaining solution. The mixture at hand could exist as a combination of any two or more states: solid-solid, solid-liquid, solid-gas, liquid-liquid, liquid-gas, gas-gas, solid-liquid-gas mixture, etc. 分离过程基本上可以被称为传质过程。可以根据分离的方法，机械或化学进行分类。分离方法的选择，取决于各方法的优点和缺点。由于与化学分离比较起来，成本较低，如果可能的话，通常采用机械分离相比。有些不能由纯机械方式分离的系统（如原油），化学分离则是余下的解决方案。混合物可能存在任何两个货两个以上的状态：固-固，固-液，固-气，液-液，液-气，气-气，固-液-气混合物等。14. In particular, his alembic was the first still with retorts which could fully purify chemicals, a precursor前身to the pot still, and its design has served as inspiration for modern