外文资料翻译
学生姓名：康英杰
专业班级： 07机制四班
指导教师：张平格
河北工程大学科信学院
Principle of Heat Treatment of Steal
The role of heat treatment in modern mechanical engineering cannot be overestimated. The
changes in the properties of metals due to heat treatment are of extremely great significance.
1、 Temperature and Time
The purpose of any heat treating process is to produce the desired changes in the structure of metal by heating to a specified temperature and by subsequent cooling.
Therefore, the main factors acting in heat treatment are temperature and time, so that any process of heat treatment can be represented in temperature —time (τ-t ) coordinates.
Heat treatment conditions are characterized by the following parameters: heating temperature max t , i.e. the maximum temperature to which an alloy metal is heated ；time of holding at the heating temperature h τ; heating rate h υ and cooling rate c υ.
If heating (or cooling) is made at a constant rate, the temperature-time relationship will be described by a straight line with a respective angle of incline.
With a varying heating (or cooling) rate, the actual rate should be attributed to the given temperature, more strictly, to an infinite change of temperature and time: that is the first derivative of temperature in time:τυd dt act /=.
Heat treatment may be a complex process, including multiple heating stages, interrupted or stepwise heating (cooling), cooling to subzero temperature, etc. Any process of heat treatment can be described by a diagram in temperature-time coordinates.
2、Formation of Austenite
The transformation of pearlite into austenite can only take place at the equilibrium critical point on a very slow heating as follows from the Fe-C constitutional diagram. Under common conditions, the transformation is retarded and results in overheating, i.e. occurs at temperatures slightly higher than those indicated in the Fe-C diagram.
When overheated above the critical point, pearlite transforms into austenite, the rate of transformation being dependent on the degree of overheating.
The time of transformation at various temperatures (depending on the degree of overheating) shows that the transformation takes place faster (in a shorter time) at a higher temperature and occurs at a higher temperature on a quicker heating.
For instance, on quick heating and holding at 780℃, the pearlite to austenite transformation is completed in 2 minutes and on holding at 740℃, in 8 minutes.
The end of the transformation is characterized by the formation of austenite and the disappearance of pearlite (ferrite + cementite). This austenite is however inhomogeneous even in the volume of a single grain. In places earlier occupied by lamellae (or grains) of a pearlite cementite, the content of carbon is greater than in places of ferritic lamellae. This is why the austenite just formed is inhomogeneous.
In order to obtain homogeneous austenite, it is essential on heating not only to pass through the point of the end of pearlite to austenite transformation, but also to overheat the steel above that point and to allow a holding time to complete the diffusion processes in austenitic grains.
The rate of homogenization of austenite appreciably depends on the original structure of the steel, in particular on the dispersion and particle shape of cementite. The transformations described occur more quickly when cementite particles are fine and, therefore, have a large total surface area.
3、Coarsening of Austenite Grains
At the beginning of pearlite to austenite transformation, the grains of austenite form at the boundaries between the ferrite and cementite ——the two structural constituents of pearlite. Since these boundaries are very developed, the transformation starts from formation of a multitude of fine grains. Therefore at the end of the transformation the austenite will be composed of a great multitude of fine grains whose size characterize what is called the original austenitic grains size.
Further heating (or holding) upon the transformation will cause coarsening of austenitic grains. The process of grain coarsening is spontaneous, since the total surface area of grains diminishes (the surface energy decreases) and a high temperature can only accelerate the rate of this process.
In that connection, two types of steels are distinguished: inherent fine grained and inherent coarse grained, the former being less liable to grain coarsening than the latter. The size of grains formed in a steel by heat treatment is called the actual grain size.
Thus, a distinction should be made between: (1) original grain, i.e. the size of austenitic grains immediately after the pearlite to austenite transformation; (2) inherent (natural) grain, i.e. the liability of austenite to grain coarsening; and (3) actual grain, i.e. the size of austenitic grains under given particular conditions.
The size of pearlitic grains at the same temperature of the austenite to pearlite transformation depends on that of the austenitic grains from which they have formed. Austenitic grains grow only during heating (but are not refined in subsequent cooling), because of which the highest
temperature a steel is heated to in the austenitic state and the inherent grain size of that steel determine the final grain size.
The properties of steel are affected only by the actual grain size and not by the inherent grain size. If two steels of the same grade (one inherent coarse grained, the other fine grained) have the same actual grain size upon heat treatment at different temperatures, their properties will also be the same; if otherwise, and many properties of the two steels will also be different.
4、Decomposition of Austenite
The austenite to pearlite transformation is essentially the decomposition of austenite into almost pure ferrite and cementite.
At the equilibrium temperature, the transformation is impossible, since the free energy of the original austenite is equal to that of the final product, pearlite. The transformation can only start at a certain undercooling when the free energy of the ferrite carbide mixture higher the degree of undercooling and the greater the difference in free energies and the transformation proceeds at a higher rate.
In the pearlite transformation, the new phases sharply differ in their composition from the initial phase; they are ferrite which is almost free of carbon, and cementite which contains 6.67 percent carbon. For this reason the austenite to pearlite transformation is accompanied with the temperature, redistribution of carbon. The rate of diffusion sharply diminishes with decreasing temperature; therefore, the transformation should be retarded at a greater undercooling.
Thus, we have come to an important conclusion that undercooling (lowering the transformation temperature) may have two opposite effects on the rate of transformation. On one austenite and pearlite, thus accelerating the transformation; on the other hand, diminished the rate of carbon diffusion, and thus slows down the transformation. The combined effect is that the rate of transformation first increases as undercooling is increased to a certain maximum and then decreases with further undercooling.
At 270℃（A1）and below 200℃, the rate of transformation is zero, since at 727℃ the free energy difference is zero and below 200℃ the rate of carbon diffusion is zero (more strictly, too low for the transformation to proceed).
As has been first indicated by I.L.Mirkin in 1939 and developed by R.F. Mehl in 1941, the formation of pearlite is the process of nucleation of pearlite and growth of pearlitic crystals. Therefore, the different rate of the pearlite transformation at various degrees of undercooling is due to the fact that undercooling differently affects the rate nucleation N and the rate of crystals growth G. at temperature A1 and below 200℃, both parameters of crystallization N and G are
equal to zero and have a maximum at an undercooling of 150~200℃.
It follows from the foregoing that as soon as the conditions are favorable, i.e. austenite is undercooling below A1, the diffusion of carbon is not zero, and centers of crystallization appear which give rise to crystal. This process occurs with time and can be represented in the form of so called kinetic curve of transformation, which shows the quantity of pearlite that has formed during the time elapsed from the beginning of the transformation.
The initial stage is characterized by a very low rate of transformation; this is what is called the incubation period. The rate of transformation increases with the progress in the transformation. Its maximum approximately corresponds to the moment when roughly 50 percent of austenite has transformed into pearlite. The rate of transformation then diminishes and finally stops.
The rate of transformation depends on undercooling. At low and high degrees of undercooling the transformation proceeds slowly, since N and G are low; in the former case, owing to a low difference in free energy, and in the later, due to a low diffusion mobility of atoms. At the maximum rate of transformation the kinetic curves have sharp peaks, and the transformation is finished in a short time interval.
At a high temperature (slightly undercooling), the transformation proceeds slowly and the incubation period and the time of the transformation proper are long. At a lower temperature of the transformation, i.e. a deeper undercooling, the rate of transformation is greater, and the time of the incubation period and of the transformation is shorter.
5、TTT Diagram or C-Curve
Having determined the time of the beginning of austenitic to pearlite transformation (incubation period) and the time of the end of transformation at various degrees of undercooling, we can construct a diagram in which the left hand curve determines the time of the beginning of transformation, i.e. the time during which austenite still exists in the undercooling state, and the section from the axis of ordinates to the curve is measure of its stability. This section is shortest at a temperature of 500~600℃, i.e. the transformation begins in a shortest time at that temperature.
The right hand curve shows the time needed to complete the transformation at a given degree of undercooling. This time is the shortest at the same temperature (500~600℃). Note that the abscissa of the diagram is logarithmic. This is done for convenience, since the rate of formation of pearlite appreciably differ (thousands of seconds near the critical point A1and only one or two seconds at the end of the curve).
The horizontal line below the curves in the diagram determines the temperature of the diffusionless martensite transformation. The martensite transformation occurs by a different mechanism and will be discussed later.
Diagrams of the type we discussed are usually called TTT diagrams (time temperature transformation), or curve, owing to the specific shape of the curves. The structure and properties of the products of austenite decomposition depends on the temperature at which the transformation has taken place.
At high temperatures, i.e. low degrees of undercooling, a coarse grained mixture of ferrite and cementite is formed which is easily distinguished in the microscope. This structure is called pearlite.
At lower temperatures, and therefore, greater degrees of undercooling, more disperse and harder products are formed. The pearlitic structure of this finer type is called sorbite.
At still lower temperatures (near the end of the C curve), the transformation products are even more disperse, so that the lamellar structure of the ferrite and transformation products only distinguishable in electron microscope. This structure is called troostite.
Thus, pearlite, sorbite and troostite are the structures of the same nature (ferrite + cementite) but a different dispersity of ferrite and cementite.
Pearlitic structures may be of two types: granular (in which cementite is present in the form of grains) or lamellar (with cementite platelets).
Homogeneous austenite always transforms into lamellar pearlite. Therefore, heating to a high temperature sets up favorable conditions for the formation of a more homogeneous structure and thus promotes the appearance of lamellar structures. Inhomogeneous austenite produces granular pearlite at all degrees of undercooling, therefore, heating to a low temperature (below Ac cm for hypereutectoid steels) results in the formation of granular pearlite on cooling. The formation of granular cementite is probably promoted by the presence of undissolved particles in austenite, which serve as additional crystallization nuclei.
6、Quasi-eutectoid
We have discussed the austenite to pearlite transformation in steels whose composition is close to eutectoid. If the content of carbon in steel differs from the eutectoid value, the pearlite transformation will be preceded with the precipitation of ferrite or cementite (as follows from the iron carbon constitutional diagram).
In hypoeutectoid steels, the transformation of austenite begins with the formation of ferrite and the saturation of the remaining solution with carbon, and in hypereutectoid steels, with the precipitation of cementite and depletion of the austenite of carbon. Under equilibrium a condition, the decomposition of austenite into ferrite and cementite (pearlite transformation) begins when the content of carbon in austenite, remained upon precipitation of excess ferrite or cementite, corresponds to 0.8% carbon.
The eutectoid which forms from undercooled austenite and has a concentration differing from the eutectoid value is called quasi-eutectoid in hypereutectoid steels contains more 0.8 percent carbon and that in hypoeutectoid steels, less than 0.8 percent, the deviation from this value being greater at lower temperature of transformation. Therefore, the lower the temperature of transformation, the less the excess ferrite (or cementite) precipitates before the pearlite transformation begins. At temperature near the bend of C curve and at lower temperature, decomposition of austenite begins without precipitation of excess phases.
If we take a hypereutectoid steel instead of hypoeutectoid, the decomposition of austenite at small degrees of undercooling will be preceded with precipitation of cementite.
7、Martensite Transformation
If the cooling rate is higher, the transformation has no time to proceed in the upper temperature range. The austenite will be undercooled to a low temperature and will transformation martensite. Such a cooling will result in hardening. Therefore, to harden steel, it should be cooled at a high rate so that austenite has no time decompose in the upper temperature range.
The lowest cooling rate needed to undercool austenite up to martensite transformation is called the critical rate of hardening. If steel is to be hardened, it should be cooled at a rate not less than the critical rate. The critical rate is lower for steels whose curve of the beginning of transformation passes farther to the right. In other words, with a lower rate of austenite to pearlite transformation, it is easier to undercool the austenite to the temperature of martensite transformation and the critical rate of hardening will be lower.
If cooling is done at a rate slightly below the critical rate, the austenite will undergo only a partial transformation in the upper temperature range and the structure will consist of the products of transformation in the upper temperature range (troostite) and martensite.
The critical rate of hardening can be determined from the diagram of isothermal decomposion of austenite. This analysis shows that a simple superposition of cooling curve on the isothermal diagram of austenite decomposition can give only an approximate quantitative estimation of a transformation occurring in continuous cooling.
钢的热处理原则
在现代机械工程中，热处理的作用不能被过高估计，但是，热处理使金属性能发生变化仍是具有重要意义的。
1、温度和时间
所有热处理工艺的目的都是通过加热温度和后期冷却获得所期望的金属结构变化。
因此，影响热处理的主要因素是温度和时间。所以，热处理过程可以用温度—时间坐标系来描述。
热处理条件可以用以下条件来描述：热处理时间、合金加热的最高温度及保温时间、加热速度和冷却速度。
如果加热或冷却连续进行，那么温度—时间曲线可以用各自的倾斜直线来描述。
在变化的加热或冷却速度下，实际的速度应归因于给定的温度，更严格的说是温度和时间的无限变化，也就是温度关于时间的一阶导数。
热处理可能是一个很复杂的过程，包括多个加热阶段或阶梯加热（或冷却），冷却至零度以下等。任何一种热处理工艺都可以用温度—时间坐标描述。
2、奥氏体的构成
根据铁碳相图，在很慢的加热速度下，珠光体向奥氏体转变，在通常条件下，转变被延迟，导致过热，即转变发生在比铁碳相图所示的温度较高一点的温度下。
当过热超过临界温度时，珠光体向奥氏体转变，转变的速度取决于过热度。
在各种温度下的转变时间显示，在较高的温度下转变的速度较快，而在较高的加热速度下发生转变的温度较高。
例如，快速加热并保温在780℃时，珠光体倒奥氏体的转变需2分钟，保温在740℃时，转变需要8分钟。
转变结束以奥氏体的形成和珠光体的消失为标准。然而，奥氏体时不均匀的，甚至含有大量的单晶体颗粒，在珠光体渗碳体的晶粒和片层占据的地方碳含量比铁素体片层的高，这就是为什么奥氏体的形成时不均匀的。
为了获得均匀的奥氏体组织，不仅要加热到珠光体到奥氏体转变结束点，还要过热并保温到奥氏体晶粒扩散过程结束。
奥氏体的均匀度取决于钢的原始结构，特别是渗碳体颗粒的形状和弥散度，渗碳体颗粒越细，接触面积就越大，转变发生的就越快。
3、奥氏体晶粒的长大
在珠光体到奥氏体转变之初，奥氏体首先是在铁素体和渗碳体的边界处产生的（这两种物质是珠光体的结构成分），因为这些边界对转变非常有利，转变以细小晶粒的形成开始，因此，在转变之末，奥氏体由大量细晶粒构成，这些细晶粒的尺寸叫做原始奥氏体晶粒尺寸。
在转变过程中进一步加热或保温会引起奥氏体晶粒的粗大，这些晶粒粗化过程是自发的，由于晶粒表面积的减小和高温条件能够加快这一过程的速度。
在那种条件下，两种钢的主要区别为：内部细晶粒和外部粗晶粒。前者晶粒粗大的倾向比后者小，这种通过加热处理在钢中形成的晶粒尺寸被叫做实际晶粒尺寸。
因此，他们的区别在于：（1）原始晶粒，即在珠光体向奥氏体转变刚结束时奥氏体的尺
寸；（2）固有（天然）晶粒，即奥氏体晶粒粗化的可能性（倾向）；和（3）实际晶粒，即在一定的珠光体转变条件下奥氏体晶粒之间的尺寸。
在奥氏体向珠光体转变的相同温度下，珠光体晶粒的尺寸取决于所形成的奥氏体晶粒。奥氏体晶粒的长大只发生在加热过程中（但没有在随后的冷却中被提纯），这是由于钢被加热到最高温度时，钢处在奥氏体状态，并且钢的本质晶粒度决定最终晶粒尺寸。
钢的性能只受实际晶粒度的影响，而不是本质晶粒度。如果两种相同品级（一种是固有的晶粒，另一种是细致纹理）的钢在不同的加热温度下，有相同的实际晶粒尺寸，他们也具有相同的性能；如果在其他条件下，这两种钢的性能将会不同。
4、奥氏体的分解
奥氏体到珠光体的转变，实际上是奥氏体分解为纯净的铁素体和渗碳体的过程。
在平衡温度下，转变是不可能发生的，因为原始奥氏体的自由能等于最终产物——珠光体的能量。只有当铁素体碳化物的混合物（珠光体）的自由能比奥氏体低，即具有一定过冷度时转变才会发生。当较低的转变温度，较高的过冷度和较大的自由能差时转变会在一个较高的速率下进行。
在珠光体转变中，新相与初始相有不同的成分；新相中大多是不含碳的铁素体，和含6.67%碳的渗碳体。基于这个原因，奥氏体到珠光体的转变，伴随着碳的扩散和再分配。扩散随着温度的降低而减小，因此，转变在一个较大过冷度下被延迟。
因此，我们得到一个重要结论，就是过冷度（低于转变温度）对转变速率具有双面的影响。一方面，较低的温度（较高的过冷度）使奥氏体的过冷度和珠光体有较大的不同；另一方面，随着碳扩散速率的降低，转变速率减慢。综上所述，转变速率由于过冷度增加到一个特定值而增加，然后，随着过冷度的降低而降低。
在727℃（A1线）到200℃之间，转变速率是0，因为727℃时的自由能是0，在200℃以下时的碳扩散速率是0（更严格的说，对转变来说太低）。
根据1939年Mirkin首先提出而后又在1941年被R.F. Mehl 发展的理论来看，珠光体的形成过程是珠光体形核及其晶粒的长大过程。因此，珠光体在不同的过冷度下有不同的转变速率，实际上是在A1线和200℃之间，不同的过冷度对形核速率和晶粒长大速度的影响，形核结晶化参数和晶粒长大速率都等于0，并且在150~200℃之间具有一个最大过冷度。
根据前面所说的，一旦条件具备，即奥氏体冷却至A1以下，碳的扩散速率将不再是0，并且结晶中心还会出现晶体，这一过程随时间的变化关系可以用转变动力曲线来描述，这条曲线显示的是珠光体数量和时间的关系。
起始阶段的特点是转变速率很低，这一阶段被称为孕育期。转变速率随着转变过程的进行而增加。他的最大值大约相当于50%的奥氏体转变成珠光体。然后，转变速率逐渐减小并最终停止。
转变速率依据过冷度而定。在较低或较高的过冷度下转变过程发生的很缓慢，因为结晶
速率和晶粒长大速度低，前者是由于自由能的不同，而后者是由于原子的流动扩散速率低。在动力曲线的顶点是转变速率的最大值，并且转变在一个很短的时间内完成。
在高温（略低于过冷度）的条件下，转变进行的缓慢，并且孕育期和转变时间很长。在较低的转变温度，即较大的过冷度下，转变速率很大，。并且孕育期和转变时间很短。
5、TTT图表或C曲线
在不同过冷度下奥氏体到珠光体的转变开始时间（孕育期）和转变的结束时间都已经确定。我们能够会出一个曲线图，曲线图的左支用来代表转变的起始时间，即在过冷状态下依然存在奥氏体，并且从纵坐标的轴心到曲线这一部分表示成分的稳定程度，这部分温度最少在500~600℃之间，即在那个温度下转变时间最短。
右支曲线描绘的是在给定的过冷度下转变完成所需要的时间，这个时间在相同温度（500~600℃）下是最短的。曲线以对数为横坐标。这样做较为方便，因为珠光体的转变略微有些差异（临界点在A1线上占据数千秒，而在曲线的最后只有一到两秒）。
在曲线下方的水平线确定的是马氏体转变的无扩散相变温度。下面将讨论使马氏体通过不同的方法发生转变。
我们讨论的图表通常被称为TTT图表（即时间、温度和转变的关系曲线）或曲线，是由于曲线的特殊形状。奥氏体分解的产物的结构和性能依据转变发生时的温度而定。
在高温条件下，即低的过冷度下，铁素体和渗碳体晶粒组成的混合物在显微镜下很容易被发现，这种结构被叫做珠光体。
因此，在较低温度下分散而质地较硬的产物将会形成，珠光体的这种细致型结构被叫做索氏体。
依旧在较低的温度下（接近C曲线的结尾），转变产物甚至会更分散，形成的铁素体的层片状结构和转变产物在电子显微镜下是可以分辨出来的，这种结构被称作屈氏体。
这样，珠光体、索氏体和屈氏体除了铁素体和渗碳体的弥散度不同外，就具有了相同的结构（铁素体+渗碳体）。
珠光体结构可能有两种类型：颗粒状（在晶粒的形成过程中渗碳体一直是存在的）和片层状（渗碳体层）。
均匀的奥氏体总是转变成层状珠光体，因此，加热到一个很高温度来为更多均匀结构的形成建立条件，也借此来提高片状结构的外观。不均匀的奥氏体在任何一个过冷度下都会产生颗粒状的珠光体，因此，加热到一个较低温度（Ac cm线以下）时，会导致在冷却时颗粒状珠光体的形成。通过控制奥氏体中未溶解碎颗粒的成分可能提高这种颗粒状珠光体的结构，而未溶解碎颗粒本身可以充当晶核。
6、伪共析钢
我们已经讨论过钢中奥氏体向珠光体的转变，产物的成分接近于共析结构。如果钢中碳含量与共析结构的不同，珠光体的转变将会发生在铁素体和渗碳体析出之前（从铁碳相图中
可以知道）。
在低碳钢中，奥氏体的转变开始于铁素体的形成和碳元素随着溶解而达到饱和情况下，而在过共析钢中，是随着渗碳体的析出和奥氏体中碳的溶解而发生的。在平衡条件下，当奥氏体中剩余碳的含量超过析出的铁素体和渗碳体时，大概相当于总含碳量的0.8%时，奥氏体分解成铁素体和渗碳体的过程才开始。
这类由过冷奥氏体组成的共熔体与真正意义上的共熔体有所不同，它在过共析钢中被称为伪共析，这种钢的含碳量超过0.8%，而在低碳钢中，含碳量低于0.8%，从这一层面讲在较低的转变温下意义就很重大了。因此，较低的转变温度下，多余的铁素体（或渗碳体）析出物较珠光体转变开始前的要少。在铁碳相图拐点附近的温度以及较低温度下，奥氏体的分解开始时并没有出现过多的析出物。
如果我们用过共析钢代替亚共析钢，奥氏体在小过冷度下的分解将会发生在渗碳体析出之前。
7、马氏体转变
如果冷却速率比较高，没有足够的时间在高温范围内发生转变，奥氏体将会过冷到一个较低的温度，并且转变成马氏体。这样的冷却将会导致硬化，因此，高硬度钢，将会以一个较高的速度冷却，以使奥氏体在高温范围内没有足够的时间发生分解。
最低的冷却速率使奥氏体发生马氏体转变，被称为硬化速率。如果钢发生硬化，冷却速度将会比临界速度高。因为钢的转变开始时的曲线延伸到右边，使得临界速度变得更低。换句话说，随着奥氏体到珠光体转变的速度越来越低，更容易使奥氏体过冷到向马氏体转变的温度，并且硬化临界速度更低。
如果冷却速度略低于临界速度，奥氏体将会经历在较高温度范围内发生局部转变，并且产物的结构将会由屈氏体和马氏体组成。
硬化临界速度可以由奥氏体转变的等温图来确定，这个分析结果只说明冷却曲线和奥氏体分解的等温图有一定的重合，也只能告诉我们在连续冷却时转变发生的近似的数量上的估计值。
2019考研英语一真题翻译参考答案及解析 考研历年真题一定要用好，研究好。结合大纲和真题来选择辅导用书是最明智的。本文带大家回顾2019考研英语一真题翻译参考答案及解析： Part C Directions: Read the following text carefully and then translate the underlined segments into Chinese. Your translation should be written neatly on the ANSWER SHEET. (10 points) It was only after I started to write a weekly column about the medical journals, and began to read scientific papers from beginning to end, that I realised just how bad much of the medical literature frequently was. I came to recognise various signs of a bad paper: the kind of paper that purports to show that people who eat more than one kilo of broccoli a week were 1.17 times more likely than those who eat less to suffer late in life from pernicious anaemia. (46) There is a great deal of this kind of nonsense in the medical journals which, when taken up by broadcasters and the lay press, generates both health scares and short-lived dietary enthusiasms. Why is so much bad science published? A recent paper, titled “The Natural Selection of Bad Science”, published on the Royal Society’s open science website, attempts to answer this intriguing and important question. It says that the problem is not merely that people do bad science, but that our current system of career advancement positively encourages it. What is important is not truth, but publication, which has become almost an end in itself. There has been a kind of inflationary process at work: (47) nowadays anyone applying for a research post has to have published twice the number of papers that would have been required for the same post only 10 years ago. Never mind the quality, then, count the number. (48) Attempts have been made to curb this tendency, for example, by trying to incorporate some measure of quality as well as quantity int o the assessment of an applicant’s papers. This is the famed citation index, that is to say the number of times a paper has been quoted elsewhere in the scientific literature, the assumption being that an important paper will be cited more often than one of small account. (49) This would be reasonable if it were not for the fact that scientists can easily arrange to cite themselves in their future publications, or get associates to do so for them in return for similar favours. Boiling down an individual’s o utput to simple metrics, such as number of publications or journal impacts, entails considerable savings in time, energy and ambiguity. Unfortunately, the long-term costs of using simple quantitative metrics to assess researcher merit are likely to be quite great. (50) If we are serious about ensuring that our science is both meaningful and reproducible, we must ensure that our institutions encourage that kind of science. 46-50参考答案及解析：
美国大学校名英文缩写 英文缩写英文全称中文全称 AAMU Alabama A&M 阿拉巴马农业机械大学ADELPHI Adelphi University 艾德菲大学AMERICAN American University 美国大学 ANDREWS Andrews University 安德鲁大学 ASU Arizona State University 亚利桑那州立大学AUBURN Auburn University 奥本大学 -B- BAYLOR Baylor University 贝勒大学 BC Boston College 波士顿学院 BGSU Bowling Green State University 博林格林州立大学BIOLA Biola University 拜欧拉大学BRANDEIS Brandeis University 布兰迪斯大学BROWN Brown University 布朗大学 BSU Ball State University 波尔州立大学 BU* Boston University 波士顿大学 BU SUNY Binghamton 纽约州立大学宾厄姆顿分校BYU Brigham Young Univ. Provo 百翰大学 *BU通常意义上指Boston University -C- CALTECH California Institute of Technology 加州理工大学 CAU Clark Atlanta University 克拉克亚特兰大大学 CLARKSON Clarkson University 克拉逊大学CLARKU Clark University 克拉克大学CLEMSON Clemson University 克莱姆森大学 CMU* Carnegie Mellon University 卡耐基梅隆大学CMU Central Michigan University 中央密歇根大学COLUMBIA Columbia University 哥伦比亚大学CORNELL Cornell University 康奈尔大学CSU* Colorado State 科罗拉多州立大学 CSU Cleveland State University 克里夫立大学CU* University of Colorado Boulder 科罗拉多大学波德分校 CU University of Colorado Denver 科罗拉多大学丹佛分校 CUA Catholic University of America 美国天主教大学 CWRU Case Western Reserve Univ. 凯斯西储大学*CMU 通常意义上指 Carnegie Mellon University *CSU 通用 *CU 通用
Aspen Plus常用词汇中英文对照表 A adiabatic 绝热的 adsorption 吸附 aircooler 空冷器 algorithm 算法 alias 又名，别名 align 使……排成直线 ambient temperature 环境温度 analysis 分析 annotation 注释 apparent component approach 表观组分方法approach 方法 aqueous 水溶液的，水的，含水的 assay化验（油品分析） ADA (assay data analysis)化验数据分析assign 指定 attach连接 attr-comps 组分属性 attr-scaling属性标量 available可用的 B backup (降液管内的清液层）高度 baffles 挡板 balance 平衡模块，平衡 base components 基准组分 base method 基本方法（包含了常见物性方法）batch 批量处理，一批 BatchFrac 间歇精馏 binary interaction 二元交互作用 blank simulation 空白模拟 block模块 Block-Var 模块变量boilup ratio 再沸比 bottoms rate 塔底产品流率 bottoms to feed ratio塔底产品流率与进料流率比brake power 轴功率 Broyden 布洛伊顿拟牛顿法 built-in 内置 C calculator 计算器 capacity 通量 capacity factor 通量负荷因子 cascade 层叠 case study 工况分析 category 类别，种类 chemical equilibrium 化学平衡 Chem-Var 化学变量 class分类 clearance 间隙 co-current 并流 coefficient 系数 column 塔 CGCCs (column grand composite curves)塔的总组合曲线 column specifications 塔设定 Compattr-Var 组分变量 component 组分 composition 组成 Compr 压缩机或涡轮机模块 comps-groups 组分分组 conceptual design 概念设计 condenser 冷凝器 condenser specification 冷凝器设定 configuration 配置
伪球迷biased fans 紧身服straitjacket 团购group buying 奉子成婚shortgun marriage 婚前性行为premartial sex 开博to open a blog 家庭暴力family volience 问题家具problem furniture 炫富flaunt wealth 决堤breaching of the dike 上市list share 赌球soccer gambling 桑拿天sauna weather 自杀Dutch act 假发票fake invoice 落后产能outdated capacity 二房东middleman landlord 入园难kindergarten crunch 生态补偿ecological compensation 金砖四国BRIC countries 笑料laughing stock 泰国香米Thai fragrant rice 学历造假fabricate academic credentials 泄洪release flood waters 狂热的gaga eg: I was gaga over his deep blue eyes when I first set eyes on him 防暑降温补贴high temperature subsidy 暗淡前景bleak prospects 文艺爱情片chick flick 惊悚电影slasher flick 房奴车奴mortgage slave 上课开小差zone out 万事通know-it-all 毕业典礼commencement 散伙饭farewell dinner 毕业旅行after-graduation trip 节能高效的fuel-efficient 具有时效性的time-efficient 死记硬背cramming 很想赢be hungry for success 面子工程face job 捉迷藏play tag 射手榜top-scorer list 学历门槛academic threshold 女学究blue stocking
2020年考研英语一翻译真题及答案解析 2017年考研英语考试已经结束!出国留学考研网在考后第一时间 为大家提供2017年考研英语一翻译真题及答案解析，更多考研资讯 请关注我们网站的更新! 2017年考研英语一翻译真题及答案解析 英语1文章明显偏学术，今年考察英语语言发展情况，文章选的英国文化教育协会，是雅思出题组织者。它的主席叫大卫格兰多的 一本书，叫《英语下一步》，他讲到整本书意思是英语将走向何处。 很有意思的是主席曾经这本书里说到了中文将以后成为世界语言。英语1考题作为序言部分作为考题。 今年英语1总体难度和去年相比，刚刚过去2016年考研题稳中 有一点点上升，没有任何难句出现，只是长句。我认为稳中上升。 第一句话有一个单词难一点，(英文)，英语全球性主导地位。翻译里没有考过。(英文)主导地位考过，但是是阅读里经常出现，翻 译都是可以的。这句话基本意思说到了，说英语的人进一步扩大， 这是一个(英文)状语从句。后面跟着有迹象表明，是主句，表明的 迹象是什么呢?从句，英语全球性主导地位在可预见地位将减弱。 fade(英文)略微有难度。我对考研阅读没有那么熟，但是2000 年出现过。如果按照新东方老师关注的精读方法来学习有很好的效果。 第二句话讲到了大卫这个人分析，会终结一些人的(英文)，他们或许会认为英语全球性地位是如此稳定。他们有一次词，是(英语) 如此稳定，英国年轻一代不需要额外学习其他的语言能力。但是会 终结年轻一代的能力。 但是组织的时候要注意一下，有些人认为英语语言地位如此稳定，英国年轻人没有必要学习什么，但是大卫的观点会终结这些人的想法。语序颠倒一下会更好。
发表日期：2015-09-29 07:48 来源：80后励志网编辑：80后点击：3321次 文章标签: 英语名言教育好文读书励志英语教育 文章导读:英语是国际性的语言，英语在我们的生活中使用率也越来越高，下面这50个很潮的英文单词，年轻人一定要学会哦！ 50个很潮的英文单词，年轻人一定要学会！ 1.预约券 reservation ticket 2.下午茶 high tea 3.微博 Microblog/ Tweets 4.裸婚 naked wedding 5.亚健康 sub-health 6.平角裤 boxers 7.愤青 young cynic 8.灵魂伴侣 soul mate 9.小白脸 toy boy 10.精神出轨 soul infidelity 11.人肉搜索 flesh search 12.浪女 dillydally girl 13.公司政治 company politics 14.剩女 3S lady(single，seventies,stuck)/left girls 15.山寨 copycat 16.异地恋 long-distance relationship 17.性感妈妈 yummy mummy ; milf(回复中指出的~) 18.钻石王老五 diamond bachelor;most eligible bachelor 20.时尚达人 fashion icon 21.御宅 otaku 22.上相的,上镜头的 photogenic 23.脑残体 leetspeak 24.学术界 academic circle 25.哈证族 certificate maniac 26.偶像派 idol type 27.住房公积金 housing funds 28.个税起征点 inpidual income tax threshold 29.熟女 cougar(源自电影Cougar Club) 30.挑食者 picky-eater 31.伪球迷 fake fans 32.紧身服 straitjacket 33.团购 group buying 34.奉子成婚 shotgun marriage 35.婚前性行为 premarital sex 36.开博 to open a blog 37.家庭暴力 family/domestic violence (由回复更正) 38.问题家具 problem furniture
2020年考研《英语一》翻译真题答案(跨考版) 文章来源于An Outline of American History，《美国历史纲要》，是一本历史学方面的专著。 46 We don’t have to learn how to be mentally healthy; it is built into us in the same way that our bodies know how to heal a cut or mend a broken bone. 【句子结构】分号连接的两个并列句，第一个并列句主干是 We don’t have to learn ，how引导宾语从句做learn的宾语，第二个 并列句主干是it is built into us in the same way，that引导定 语从句修饰先行词way，that定语从句中主干是our bodies know，how引导宾语从句做know的宾语。 【参考译文】我们无需刻意去了解学习才能让心理更健康，它正 如我们的身体知道怎样让伤口愈合和修复骨折一样，是根植于我们体 内的/是我们与生俱来的水平。 47 Our mental health doesn’t really go anywhere; like the sun behind a cloud, it can be temporarily hidden from view, but it is fully capable of being restored in an instant. 【句子结构】分号连接的两个并列句, 第一个并列句主谓结构， 很简单，第二个并列句中，like the sun behind a cloud是状语， but 连接两个并列分句，包括短语be hidden from 和be capable of. 涉及被动语态的翻译方法。 【参考译文】我们的心理健康并不是真的消失不见，就像云朵背 后的太阳，它也许暂时被遮挡，但是它也能够在瞬间重焕光芒。 48 Mental health allows us to view others with sympathy if they are having troubles, with kindness if they are in pain, and with unconditional love no matter who they are.
中外高校校名国内研究所中文全称和英文缩写 对照 集团文件发布号：（9816-UATWW-MWUB-WUNN-INNUL-DQQTY-
中文全称英文缩写 浙江大学ZHEJIANG UNIV 中国科学院CHINESE ACAD SCI 清华大学TSINGHUA UNIV 东南大学SOUTHEAST UNIV 大连理工大学DALIAN UNIV TECHNOL 南京大学NANJING UNIV 四川大学SICHUAN UNIV 上海交通大学SHANGHAI JIAO TONG UNIV 中山大学SUN YAT SEN UNIV 华中科技大学HUAZHONG UNIV SCI TECHNOL 北京大学PEKING UNIV 山东大学SHANDONG UNIV 复旦大学FUDAN UNIV 南开大学NANKAI UNIV 北京邮电大学BEIJING UNIV POSTS TELECOMMUN 中国科学技术大学UNIV SCI TECHNOL CHINA 吉林大学JILIN UNIV 西安交通大学XI AN JIAO TONG UNIV 哈尔滨工业大学HARBIN INST TECHNOL 天津大学TIANJIN UNIV 兰州大学LANZHOU UNIV 华南理工大学S CHINA UNIV TECHNOL 武汉大学WUHAN UNIV 湖南大学HUNAN UNIV 华南师范大学S CHINA NORMAL UNIV 北京航天航空大学BEIJING UNIV AERONAUT ASTRONAUT 东北大学NORTHEASTERN UNIV 电子科技大学UNIV ELECT SCI TECHNOL CHINA 华东科技大学 E CHINA UNIV SCI TECHNOL 中南大学CENT S UNIV 西安电子科技大学XIDIAN UNIV 同济大学TONGJI UNIV 厦门大学XIAMEN UNIV 北京交通大学BEIJING JIAOTONG UNIV 东吴大学SOOCHOW UNIV 安徽大学ANHUI UNIV 北京理工大学BEIJING INST TECHNOL 香港城市大学CITY UNIV HONG KONG 湘潭大学XIANGTAN UNIV 北京师范大学BEIJING NORMAL UNIV
第一单元 “一年365 天，一周7 天，一天24 小时，生意始终在进行，那意味着一年365 天，一周7 天，一天24 小时，竞争也同样在进行，”豪特说，“公司取胜的方法之一就是要更快地到达‘目的地’！这就是说，你不仅要把所有能支持公司快速运转的功能都调动起来，而且还得知道如何决定‘目的地’是哪里。这样，不仅对那些行动快速的人们，也对那些思维敏捷，并有勇气按自己的想法行事的人们都提出了要求。这需要全公司各部门的运作，而不仅仅是管理部门的工作。 “Business happens 24/7/365, which means that competition happens 24/7/365, as well,” says Haut. “One way that companies win is by getting …there? faster, which means that you not only have to mobilize all of the functions that support a business to move q uickly, but you have to know how t o decide where …there? is! This creates a requirement not only for people who can act quickly, but for those who can think fast with the courage to act on their convictions. This needs to run throughout an organization and is not exclusive to management.” 最后，职业地位包含对职业标准的遵守。很多律师通过在行业内外把自己塑造成一个具有良好职业道德的典范来找到自我价值。对那些在所有职业行为中都表现出极度正直和谦逊有礼的律师们来说，当管理阶层对他们理应受到的特别尊重表示肯定时，便又获得了另一种形式的精神报酬。 Lastly, professional status encompasses adherence to ethical standards. Most lawyers find self worth in setting an example—both within the profession and within the larger society—as ethical actors. When management affirms the special respect due to lawyers who act with the utmost integrity and civility in all of their professional dealings, it provides yet another form of compensation. 第四单元 很多研究发现婴儿获得关爱的质量会影响到他们以后的交友，在学校的表现，如何应对陌生的或可能充满压力的情况，以及他们成年后如何建立并且维系情感连系。正是因为这些原因，人们与家庭成员的早期亲密关系才如此至关重要。在人情冷漠的环境中(如孤儿院，某些寄养家庭，或缺乏关爱的家庭)长大的孩子会出现情感和社会性发育不良，语言和运动技能迟缓，以及精神健康问题。Much research shows that the quality of care infants receive affects how they later get along with friends, how well they do in school, how they react to new and possibly stressful situations, and how they form and maintain loving relationships as adults. It is for these reasons thatpeople's early intimate relationships within their family of origin1 are so critical. Children who are raised in impersonal environments (orphanage, some foster homes, or unloving families) show emotional and social underdevelopment, language and motor skills retardation, and mental health problems. 一开始让人相互吸引的是什么?许多人相信“世上有一个人是你为之而生的”，而且命运会将你俩带到一起。这样的想法很浪漫却不现实。实证研究发现，是文化标准和价值观而非命运，将人们连系在一起。我们错过了成千上万的可能的爱人，因为他们早就被正式的或非正式的挑选理想爱人的准则筛选出局，这些准则包括年龄、种族、地域、社会阶层、宗教、性倾向、健康状况或外表。 What attracts individuals to each other in the first place? Many people believe that "there's one person out there that one is meant for" and that destiny will bring them together. Such beliefs are romantic but unrealistic. Empirical studies show that cultural norms and values, not fate, bring people together We will never meet millions of potential lovers because they are "filtered out" by formal or informal rules on partner eligibility due ton factors such as age, race, distance, Social class, religion, sexual orientation, health, or physical appearanc e. 第五单元 做瑜伽没有场地的限制，一套瑜伽动作通常需要20 分钟到两个小时或者更多的时间，而一个小时左右的时间则是一系列动作和冥想的最佳选择。根据瑜伽师和学派的不同，一些瑜伽动作做起来辛苦异常，而另一些却只是在呼吸和心跳平稳的情况下调整和伸展肢体。每天练习瑜伽会达到最好的效果，随着动作越来越熟练，你就可以加大强度和难度这样瑜伽就能成为你相伴终生的日常锻炼方式了。练习基础的瑜伽动作即可收到增强力量，改善柔韧性并使人感到舒适的效果，但要想达到完美和高深的境界还是需要日积月累的练习，这也是瑜伽吸引人的地方之一。 Yoga routines can take anywhere from 20 minutes to two or more hours, with one hour being a good time investment to perform a sequence of postures and a meditation. Some yoga routines, depending on the teacher and school, can be as strenuous as the most difficult workout, and some routines merely stretch and align the body while the breath and heart rate are kept slow and steady. Yoga achieves its best results when it is practiced as a daily discipline, and yoga can be a life-long exercise routine, offering deeper and more challenging positions as a practitioner becomes more adept. The basic positions can increase a person?s strength, flexibility and sense of well-being almost immediately, but it can take years to perfect and deepen them, which is an appealing and stimulating aspect of yoga for many. 第七单元 人性的恒定性是众所周知的，因为没有人相信一个人能够从根本上改变他的本性。这就是为什么一个恶名远扬的人很难重建公众对他的信心。人们凭经验知道某一年中表现出无赖性格的人不太可能在第二年有任何改观。小偷也不会变成值得信赖的员工。吝
南京大学Nanjing University 东南大学Southeast University 南京航空航天大学Nanjing University of Aeronautics and Astronautics 南京理工大学Nanjing university ofscience ＆technology 南京工业大学Nanjing tech university 南京邮电大学Nanjing University of Posts and Telecommunications 南京林业大学Nanjing forestry university 南京信息工程大学Nanjing University of Information Science & Technology 南京农业大学Nanjing Agricultural University 南京医科大学Nanjing medical university 南京中医药大学Nanjing university of Chinese medicine 中国药科大学China Pharmaceutical University 南京师范大学Nanjing Normal University 南京财经大学Nanjing University Of Finance & Economics 江苏警官学院Jiangsu police institute 南京体育学院Nanjing Sport Institute 南京艺术学院Nanjing University of the Arts 三江学院Sanjiang university 南京工程学院Nanjing institute of technology 南京审计大学Nanjing audit university 南京晓庄学院Nanjing xiaozhuang university 南京特殊教育师范学院Nanjing Normal University Of Special Education 南京森林警察学院Nanjing forest police college 东南大学成贤学院southeast university chengxian college 金陵科技学院jinling institute of technology 南京大学金陵学院Nanjing university jinling college 南京理工大学紫金学院Nanjing University of Science and Technology ZiJin College 南京航空航天大学金城学院 nanhang Jincheng college 中国传媒大学南广学院Communication University of China, Nanguang College
atm 1atm为一个标准大气压 Bar 巴压力单位 BaseMethod 基本方法包含了一系列物性方程 Batch 批量处理 BatchFrac 用于两相或三相间歇式精馏的精确计算 Benzene 苯 Blocks 模型所涉及的塔设备的各个参数 Block-Var 模块变量 ChemVar 化学变量 Columns 塔 Columnspecifications 塔规格 CompattrVar 组分变量 Components 输入模型的各个组成 ComponentsId 组分代号 Componentsname 组分名称 Composition 组成 Condenser 冷凝器 Condenserspecifications 冷凝器规格 Constraint 约束条件 Conventional 常规的 Convergence 模型计算收敛时所涉及到的参数设置 Databrowser 数据浏览窗口 Displayplot 显示所做的图 Distl 使用Edmister方法对精馏塔进行操作型的简捷计算 DSTWU 使用Winn-Underwood-Gilliland方法对精馏塔进行设计型的简捷计算 DV精馏物气相摩尔分率 ELECNRTL 物性方程适用于中压下任意电解质溶液体系 Extract 对液体采用萃取剂进行逆流萃取的精确计算 Find 根据用户提供的信息查找到所要的物质 Flowsheetingoptions 流程模拟选项 Formula 分子式 Gasproc 气化 Heat Duty 热负荷 HeatExchangers 热交换器 Heavy key 重关键组分 IDEAL 物性方程适用于理想体系 Input summary 输入梗概 Key component recoveries 关键组分回收率 kg/sqcm 千克每平方厘米 Lightkey 轻关键组分 Manipulated variable 操作变量 Manipulators 流股调节器
50个很潮的英文单词，年轻人一定要学会！ 发表日期：2015-09-29 07:48 来源：80后励志网编辑：80后点击：3321次 文章标签: 英语名言教育好文读书励志英语教育 文章导读:英语是国际性的语言，英语在我们的生活中使用率也越来越高，下面这50个很潮的英文单词，年轻人一定要学会哦！ 50个很潮的英文单词，年轻人一定要学会！ 1.预约券 reservation ticket 2.下午茶 high tea 3.微博 Microblog/ Tweets 4.裸婚 naked wedding 5.亚健康 sub-health 6.平角裤 boxers 7.愤青 young cynic 8.灵魂伴侣 soul mate 9.小白脸 toy boy 10.精神出轨 soul infidelity 11.人肉搜索 flesh search 12.浪女 dillydally girl 13.公司政治 company politics 14.剩女 3S lady(single，seventies,stuck)/left girls 15.山寨 copycat 16.异地恋 long-distance relationship 17.性感妈妈 yummy mummy ; milf(回复中指出的~) 18.钻石王老五 diamond bachelor;most eligible bachelor
20.时尚达人 fashion icon 21.御宅 otaku 22.上相的,上镜头的 photogenic 23.脑残体 leetspeak 24.学术界 academic circle 25.哈证族 certificate maniac 26.偶像派 idol type 27.住房公积金 housing funds 28.个税起征点 inpidual income tax threshold 29.熟女 cougar(源自电影Cougar Club) 30.挑食者 picky-eater 31.伪球迷 fake fans 32.紧身服 straitjacket 33.团购 group buying 34.奉子成婚 shotgun marriage 35.婚前性行为 premarital sex 36.开博 to open a blog 37.家庭暴力 family/domestic violence (由回复更正) 38.问题家具 problem furniture 39.炫富 flaunt wealth 40.决堤 breaching of the dike 41.上市 list share 42.赌球 soccer gambling 43.桑拿天 sauna weather 44.自杀 Dutch act 45.假发票 fake invoice 46.落后产能 outdated capacity 47.二房东 middleman landlord 48.入园难 kindergarten crunch 49.生态补偿 ecological compensation 50.金砖四国 BRIC countrie
Unit One An Image or a Mirage V. Translation A. 从更大的范围上讲，选民们往往仅因为某个政客的外表整洁清秀而对他做出有利的反应。他的对手则因为没有生就一副令人信任的外表而常常遭到否定的评价。这种判断是错误的，其后果可能是灾难性的。就算许多选民投一位候选人的票完全是出于政治原因，但本不该当选的人，如果他有整洁清秀的形象，就会使他在势均力敌的选举中占有优势。 我们常常根据一个人的表达能力而做出轻率的判断。再回到政治这一话题上来，许多选民仅仅根据候选人公开演讲的方式就对他的能力做出判断。然而，一个候选人可能非常善于演说，但并不一定能胜任他所竞选的职位。我认识许多才能杰出的人物，他们只是没有培养自己在公开场合演讲的能力，但在与别人一对一的交流中却表现极为出色。这种能充分表达自己见解的能力，固然十分重要，但我们对于那些让人感觉善于辞令的人，往往产生错误的印象，因为很多情况下这种优点仅仅只是“表面现象”。不难想象，一位外表整洁清秀、讲话娓娓动听的政治家会轻而易举地战胜一位不事张扬但更为合格的对手。他之所以取胜仅仅是因为他的形象令人信服。 B. If you want a winning image with others, your first concern must be a winning self-image. The individual who has a losing self-image will never be able to project a winning image to others. He may be able to fool some people for a while, but his poor self-image will eventually make it impossible for him to relate favorably to others. Throughout the ages, great philosophers have stated, “Y ou are what you think you are.” It is imperative for you to have good image of yourself if you want to create the same impression in others. No matter who you are, everything worthwhile will depend on your own self-image. Y our happiness will be based on it. Y ou will live only one life, and in order to enjoy it, you must have a winning self-image. Since we can all choose how we want to think ourselves, we should try to have positive, winning thoughts. In your own attempt to build a winning image you must begin with the self — otherwise, the