非均相分离
（1）重力沉降
滞流区的沉降公式、降尘室的沉降条件、在降尘室中设置水平隔板（例3－3）、流型校核、降尘室的生产能力
（2）离心沉降
旋风分离器的压强降、旋风分离器的临界粒径、沉降流型校核（离心沉降速度、层流）、多个旋风分离器的并联（例3－5） 旋风分离器的操作原理
三、简答题（10分）
含尘气体通过降尘室后，固体颗粒浓度降低。若其它条件不变，且颗粒沉降处在层流区，试分析气体的温度升高时出口气体的含尘量如何变化？ 颗粒在层流区的沉降速度计算式为μ
ρρ18)(2g d u s t -= 而气体的黏度随温度的升高而增大，所以t u 会减小。 （5分）
含尘气体通过沉降室，颗粒得到分离的必需条件为 t u H u l ≥
对于临界最小沉降速度，由于气体黏度的增大，最小捕集颗粒直径增大，使得出口气体的含尘量增大（5分）
2． 临界粒径
3、分析颗粒的自由沉降过程
3、（10分）一种测定粘度的仪器由一钢球及玻璃筒组成。测试时筒内充被测液体，记录钢球下落一定距离的时间，球的直径为6mm ，下落距离为20cm ，测试一种糖浆时记下的时间间隔为7.32秒，此糖浆的密度为1300 kg/m 3，钢球的密度为7900 kg/m 3，求此糖浆的粘度。
七、计算题（10分）拟采用降尘室除去常压炉气中的球形尘粒。降尘室的宽和长分别为2m 和6m ,气体处理量为1标m 3/s ，炉气温度为427℃，相应的密度ρ=0.5kg/m 3，粘度μ=3.4×10-5Pa.s ，固体密度ρS =400kg/m 3操作条件下，规定气体速度不大于0.5m/s ，试求：
1．降尘室的总高度H ，m ； 2．理论上能完全分离下来的最小颗粒尺寸。
七、（10分） 解：1）降尘室的总高度H
s m t V V S /564.2273
427273127327330=+?=+= (1) m 564.25
.02564.2bu V H S -?=== (1)
2）理论上能完全出去的最小颗粒尺寸
用试差法由u t 求d min 。
s /m 214.06
2564.2bl V u s t =?== （2） ()()m 1078.5807
.95.04000214.0104.318g u 18d 55s t min --?=?-???=ρ-ρμ= （2） 假设沉降在斯托克斯区
()()
()s /m 103.0104.318807.95.04000104018g d u 526s 2t =???-?=μρ-ρ='-- (1) 1182.01014.35.0214.01078.5du Re 5
5t t <=????=μρ=-- (2) 核算沉降流型, ∴原假设正确，最小粒径为5.78*10-5m 。 （1）
二、（10分）某厂炉气中含有最小直径为10μm 的尘粒，尘粒的密度为4000kg/m 3，炉气温度为700K 。在此温度下，气体黏度为
3.4×10-5Pa.s ，密度为0.5kg/m 3。现要求炉气处理量为8000kg/h 。采用多层降尘室除尘粒，若降尘室中的隔板已选定长度为5m ，宽为3m ，且降尘室总高不超过
4.8m 。试计算降尘室中隔板间的距离。
二、（10分，05考研）一种测定粘度的仪器由一钢球及玻璃筒组成。测试时筒内充被测液体，记录钢球下落一定距离的时间，
球的直径为6mm ，下落距离为200mm ，测试一种糖浆时记下的时间间隔为7.32秒，此糖浆的密度为1300 kg/m 3，钢球的密度为7900 kg/m 3，求此糖浆的粘度是多少厘泊。
Section I Use of English Directions: Read the following text. Choose the best word(s) for each numbered blank and mark A, B, C or D on the ANSWER SHEET. (10 points) Weighing yourself regularly is a wonderful way to stay aware of any significant weight fluctuations. 1 , when done too often, this habit can sometimes hurt more than it 2 . As for me, weighing myself every day caused me to shift my focus from being generally healthy and physically active to focusing 3 on the scale. That was bad to my overall fitness goals. I had gained weight in the form of muscle mass, but thinking only of 4 the number on the scale, I altered my training program. That conflicted with how I needed to train to 5 my goals. I also found that weighing myself daily did not provide an accurate 6 of the hard work and progress I was making in the gym. It takes about three weeks to a month to notice any significant changes in your weight 7 altering your training program. The most 8 changes will be observed in skill level, strength and inches lost. For these 9 , I stopped weighing myself every day and switched to a bimonthly weighing schedule 10 . Since weight loss is not my goal, it is less important for me to 11 my weight each week. Weighing every other week allows me to observe and 12 any significant weight changes. That tells me whether I need to 13 my training program. I use my bimonthly weigh-in 14 to get information about my nutrition as well. If my training intensity remains the same, but I’m constantly 15 and dropping weight, this is a 16 that I need to increase my daily caloric intake. The 17 to stop weighing myself every day has done wonders for my overall health, fitness and well-being. I’m experiencing increased zeal for working out since I no longer carry the burden of a 18 morning weigh-in. I’ve also experienced greater success in achieving my specific fitness goals, 19 I’m trai ning according to those goals, not the numbers on a scale. Rather than 20 over the scale, turn your focus to how you look,
化工原理试题库 试题一 一：填空题（18分） 1、 某设备上，真空度的读数为80mmHg ，其绝压=________02mH =__________Pa. 该地区的大气压为 720mmHg 。 2、 常温下水的密度为1000 3m Kg ，粘度为1cp ，在mm d 100=内的管内以s m 3 速度流动，其流动类 型为 ______________。 3、 流体在管内作湍流流动时，从中心到壁可以__________.___________._ _________________. 4、 气体的粘度随温度的升高而_________，水的粘度随温度的升高_______。 5、 水在管路中流动时，常用流速范围为_______________s m ,低压气体在管路中流动时，常用流速范围 为_______________________s m 。 6、 离心泵与往复泵的启动与调节的不同之处是：离心泵_________________. __________________.往复泵___________________.__________________. 7、在非均相物糸中，处于____________状态的物质，称为分散物质，处于 __________状态的物质，称为分散介质。 8、 间竭过滤操作包括______._______.________._________.__________。 9、 传热的基本方式为___________.______________.__________________。 10、工业上的换热方法有_________.__________.__________.____________。 11、α称为_______________，其物理意义为____________________________. __________________________，提高管内α值的有效方法____________. 提高管外α值的有效方法______________________________________。 12、 蒸汽冷凝有二种方式，即_____________和________________ 。其中， 由于_________________________________________，其传热效果好。 二：问答题（36分） 1、 一定量的流体在圆形直管内作层流流动，若将其管径增加一倍，问能量损 失变为原来的多少倍？ 2、 何谓气缚现象？如何防止？ 3、何谓沉降？沉降可分为哪几类？何谓重力沉降速度？ 4、在列管式换热器中，用饱和蒸汽加热空气，问： （1） 传热管的壁温接近于哪一种流体的温度？ （2） 传热糸数K 接近于哪一种流体的对流传热膜糸数？ （3） 那一种流体走管程？那一种流体走管外？为什么？ 5、换热器的设计中为何常常采用逆流操作？ 6、单效减压蒸发操作有何优点？ 三：计算题(46分) 1、 如图所示，水在管内作稳定流动，设管路中所有直管管路的阻力糸数为03.0=λ，现发现压力表上 的读数为052mH ，若管径为100mm,求流体的流量及阀的局部阻力糸数？ 2、 在一 列管式换热器中，用冷却将C 0100的热水冷却到C 0 50，热水流量为h m 360，冷却水在管 内 流动，温度从C 020升到C 0 45。已 知传热糸数K 为C m w .20002， 换热管为mm 5.225?φ的钢管，长 为3m.。求冷却水量和换热管数 （逆流）。
化工原理-考研真题详解 1．某液体在内径为 的水平管路中作稳定层流流动其平均流速为u，当它以相同的体积流量通过等长的内径为 （ ）的管子时，则其流速为原来的U倍，压降 是原来的倍。[四川大学2008研] 【答案】4 16查看答案 【解析】由流量 可得，流速 ，因此有：
，即流速为原来的4倍。 根据哈根-泊肃叶（Hagen-Poiseuille）公式 （ 为压强降），则有： 因此，压降是原来的16倍。 2．一转子流量计，当通过水流量为1m3/h时，测得该流量计进、出间压强降为20Pa；当流量增加到1.5m3/h时，相应的压强降为。[四川大学2008研] 【答案】20Pa查看答案 【解析】易知 ，当转子材料及大小一定时，
、 及 为常数，待测流体密度可视为常数，可见 为恒定值，与流量大小无关。 3．油品在φ 的管内流动，在管截面上的速度分布可以表示为 ，式中y为截面上任一点至管内壁的径向距离（m），u为该点上的流速（m/s）；油的粘度为 。则管中心的流速为m/s，管半径中点处的流速为m/s，管壁处的剪应力为
。[清华大学2001研] 【答案】0.4968 0.3942 1查看答案【解析】管内径 。 在管中心处 ，则流速为 。 在管半径中心处 ，则流速为 。 由题意可知 ，则管壁处剪切力为：
4．某转子流量计，其转子材料为不锈钢，当测量密度为 的空气的流量时，最大流量为 。现用来测量密度为 氨气的流量时，其最大流量为 。[清华大学2000研] 【答案】490查看答案 【解析】对转子流量计，在同一刻度下有： 。 因此，其最大流量为
2005年4月高等教育自学考试全国统一命题考试 英语（二）试卷及答案 （课程代码：00015） PART ONE （50 POINTS） Ⅰ.Vocabulary and Structure (10 points, 1 point for each item) 从下列各句四个选项中选出一个最佳答案，并在答题卡上将相应的字母涂黑。 1.Would’t you rather your child ______ successful with his study and won the scholarship? A. became B. become C. would become D. becomes 2. Although Tom is satisfied with his academic achievement, he wonders _______will happen to his family life. A. it B. that C. what D. this 3. We hope that all the measures against sandstorms, ________ was put forward by the committee, will be considered seriously at the meeting . A. while B. after C. since D. as 4. We cannot leave this tough job to a person_________. A. who nobody has confidence B. in whom nobody has confidence C. for whom nobody has confidence D. who everyone has confidence of 5. You are the best for the job _____ you apply your mind to it . A. until B. if only C. in case D. unless 6.Hey, leave _____!I hate people touching my hair. A. behind B. out C. off D. over 7.I thought the problem of water shortage would ________ at the meeting but nobody mentioned it. A. come up B. come up to C. come over D. come to 8.Mr.Smith , can I ________ you for a minute? I’d like to hear your opinion on this issue. A. say a word with B. have words with C. mention a word with D. have a word with 9.There is a deadlock (僵局) in the discussion when neither side gives ________ to the over . A. a way B. way C. the way D. its way 10. This type of desk and chair can be adjusted ________ the height of students at different ages. A. with B. for C. to D. in Ⅱ.Cloze Test (10 points, 1 point for each item) 下列短文中有十个空白，每个空白有四个选项。根据上下文要求选出最佳答案，并在答题卡上将相应的字母涂黑。 For over a hundred years Japan has consistently spent large sums of money and considerable human resources in an effort to obtain technology. Her ability to negotiate __11___ by the fact most of the technology she wanted was no commercial secrets. Japan’s __12__ has also been strengthened by the fact that her internal market was large, so that __13__ to this market could be offered to multinational companies as an attraction to them to grant licenses. Besides, Japan’s work force was disciplined, so it was capable __14__ applying the information it acquired. Finally, American and European companies, who were __15__ licensers, felt that the
2002 Directions：Translate the following passage into Chinese and put your translation on the ANSWER SHEET． Since 1981，farmers in Holland have been encouraged to adopt“green”farming techniques that were thought to benefit plant and bird life．Farmers who have voluntarily adopted these measures are compensated by the European Union．The goal of the program is to work against the negative effects of modem fanning，such as declines in species diversity and the disturbance of local nesting grounds．The“green”methods of farming cost the European Union about 1.7 billion Euros annually．This is about 4 percent of the budget for“Common Agricultural Policy,”and the compensation is expected to rise to 10 percent within the next few years． Various forms of“green farming”employed around the world have proved successful, and all new methods thought to be environmentally sensitive should be subject to sound scientific evaluation to determine whether they are actually meeting the intended goals． Part V Writing(30 minutes，15 points) Directions：You are to write in no less than 120 words about the title “What I Consider Important in Life”．Your composition should be based on the Chinese outline given below．
1.用化工原理解释“开水不响，响水不开”的现象。 水中能溶有少量空气，容器壁的表面小空穴中也吸附着空气，这些小气泡起气化核的作用。水对空气的溶解 度及器壁对空气的吸附量随温度的升高而减少，当水被加热时，气泡首先在受热面的器壁上生成。气泡 生成之后 ,由于水继续被加热，在受热面附近形成过热水层，它将不断地向小气泡内蒸发水蒸汽,使泡内的 压强（空气压与蒸汽压之和）不断增大，结果使气泡的体积不断膨胀，气泡所受的浮力也随之增大，当气 泡所受的浮力大于气泡与壁间的附着力时，气泡便离开器壁开始上浮。 在沸腾前，窗口里各水层的温度不同,受热面附近水层的温度较高，水面附近的温度较低。气泡在上升过程中不仅泡内空气压强 P。随水温的降低而降低，泡内有一部分水蒸汽凝结成饱和蒸汽,压强亦在减小，而外界压强基本不变，此时，泡外压强大于内压强，于是上浮的气泡在上升过程中体积将缩小，当水温接近沸 点时，有大量的气泡涌现，接连不断地上升，并迅速地由大变小，使水剧烈振荡，产生" 嗡 ,嗡 " 的响声，这就是 "响水不开 " 的道理。 对水继续加热，由于对流和气泡不断地将热能带至中、上层,使整个溶器的水温趋于一致，此时，气泡脱 离器壁上浮，其内部的饱和水蒸汽将不会凝结，饱和蒸汽压趋于一个稳定值。气泡在上浮过程中，液体对气 泡的静压强随着水的深度变小而减小，因此气泡壁所受的外压强与其内压强相比也在逐渐减小，气泡液 --气分界面上的力学平衡遭破坏，气泡迅速膨胀加速上浮，直至水面释出蒸汽和空气，水开始沸腾了，也 就是人们常说的 "水开了 " ，由于此时气泡上升至水面破裂，对水的振荡减弱 ,几乎听不到 " 嗡嗡声 "，这就是 " 开水不响 " 的原因。 2.试举例说明分子动量扩散、热量扩散和质量扩散现象，并阐述三个过程的物理 本质和共性特征。 动量传递——在垂直于实际流体流动方向上，动量由高速度区向低速度区的转移。如：流体输送，过滤， 沉降。 热量传递——热量由高温度区向低温度区的转移。如：干燥，换热，蒸发。 质量传递——物系中一个或几个组分由高浓度区向低浓度区的转移。如：吸收，精馏，萃取，吸附、膜分 离。传质和传热：结晶、干燥。 由此可见，动量、热量与质量传递之所以发生，是由于物系内部存在着速度、温度和浓度梯度的缘故。可 以用类似的数学模型来描述，都可用传递方程遵维象方程：物理量的传递速率=推动力 / 阻力。牛顿粘性定律、傅里叶定律、费克扩散定律都是描述分子运动引起传递的现象定律，通量与梯度成正比。 3.简要阐述通过圆管内流体流动实验测定摩擦系数的方法。
山东大学837化工原理考研真题及笔记详解 2021年山东大学《837化工原理》考研全套 目录 ?山东大学《837化工原理》历年考研真题汇编 ?全国名校化工原理考研真题汇编（含部分答案） 说明：本部分收录了本科目近年考研真题，方便了解出题风格、难度及命题点。此外提供了相关院校考研真题，以供参考。 2．教材教辅 ?陈敏恒《化工原理》（第4版）笔记和课后习题（含考研真题）详解?[预售]陈敏恒《化工原理》（第4版）（上册）配套题库【考研真题精选＋章节题库】 ?[预售]陈敏恒《化工原理》（第4版）（下册）配套题库【考研真题精选＋章节题库】 ?夏清《化工原理》（第2版）（上册）配套题库【名校考研真题＋课后习题＋章节题库＋模拟试题】
?夏清《化工原理》（第2版）（下册）配套题库【名校考研真题＋课后习题＋章节题库＋模拟试题】 说明：以上为本科目参考教材配套的辅导资料。 ? 试看部分内容 名校考研真题 绪论 本章不是考试重点，暂未编选名校考研真题，若有将及时更新。 第1章流体流动 一、填空题 1．某液体在内径为的水平管路中作稳定层流流动其平均流速为u，当它以相同的体积流量通过等长的内径为（）的管子时，则其流速为原来的倍，压降是原来的倍。[四川大学2008研] 【答案】4 16查看答案 【解析】由流量可得，流速，因此有：，即流速为原来的4倍。 根据哈根-泊肃叶（Hagen-Poiseuille）公式（为压强降），则有：
因此，压降是原来的16倍。 2．一转子流量计，当通过水流量为1m3/h时，测得该流量计进、出间压强降为20Pa；当流量增加到1.5m3/h时，相应的压强降为。[四川大学2008研]【答案】20Pa查看答案 【解析】易知，当转子材料及大小一定时，、及为常数，待测流体密度可视为常数，可见为恒定值，与流量大小无关。 3．油品在φ的管内流动，在管截面上的速度分布可以表示为 ，式中y为截面上任一点至管内壁的径向距离（m），u为该点上的流速（m/s）；油的粘度为。则管中心的流速为 m/s，管半径中点处的流速为 m/s，管壁处的剪应力为。[清华大学2001研]【答案】0.4968 0.3942 1查看答案 【解析】管内径。 在管中心处，则流速为。 在管半径中心处，则流速为。 由题意可知，则管壁处剪切力为： 4．某转子流量计，其转子材料为不锈钢，当测量密度为的空气的流量时，最大流量为。现用来测量密度为氨气的流量时，其最大流量为。[清华大学2000研]
2011年研究生入学考试英语二真题 Section I Use of English Directions：Read the following text. Choose the best word(s) for each numbered black and mark A, B, C or D on ANSWER SHEET 1. (10 points) "The Internet affords anonymity to its users — a boon to privacy and freedom of speech. But that very anonymity is also behind the explosion of cybercrime that has 1 across the Web. Can privacy be preserved 2 bringing a semblance of safety and security to a world that seems increasingly 3 ? Last month, Howard Schmidt, t he nation’s cyberczar, offered the Obama government a4 to make the Web a safer place —a “voluntary identify” system that would be the high-tech 5 of a physical key, fingerprint and a photo ID card, all rolled 6 one. The system might use a smart identity card, or a digital credential 7 to a specific computer, and would authenticate users at a range of online services. The idea is to 8 a federation of private online identify systems. Users could 9 which system to join, and only registered users whose identities have been authenticated could navigate those systems. The approach contrasts with one that would require an Internet driver’s license10 by the government. Google and Microsoft are among companies that already have sign-on” systems that make it possible for users to 11 just once but use many different services. 12, the approach would create a “walled garden” in safe “neighborhoods” and bright “streetlights” to establish a sense of 13 community. Mr. Schmidt described it as a “voluntary ecosystem” in which individuals and organizations can complete online transactions with 14 ,trusting the identities of the infrastructure that the transaction runs 15 .'" Still, the administration’s plan has16 privacy rights activists. Some applaud the approach; others are concerned. It seems clear that such an initiative push toward what would 17be a license” mentality. The plan has also been greeted with 18by some experts, who worry that the “voluntary ecosystem” would still leave much of the Internet 19 .They argue that should be 20 to register and identify themselves, in drivers must be licensed to drive on public roads. 1． A.swept B.skipped C.walked D.ridden 2． A.for B.within C.while D.though 3． A.careless https://www.doczj.com/doc/8412422608.html,wless C.pointless D.helpless 4． A.reason B.reminder https://www.doczj.com/doc/8412422608.html,promise D.proposal 5． https://www.doczj.com/doc/8412422608.html,rmation B.interference C.entertainment D.equivalent 6． A.by B.into C.from D.over 7． A.linked B.directed C.chained https://www.doczj.com/doc/8412422608.html,pared 8． A.dismiss B.discover C.create D.improve 9． A.recall B.suggest C.select D.realize 10． A.relcased B.issued C.distributed D.delivered 11． A.carry on B.linger on C.set in D.log in 12． A.In vain B.In effect C.In return D.In contrast 13． A.trusted B.modernized C.thriving https://www.doczj.com/doc/8412422608.html,peting 14． A.caution B.delight C.confidence D.patience
全国至自学考试英语二历年真题及答案全集精 编W O R D版 IBM system office room 【A0816H-A0912AAAHH-GX8Q8-GNTHHJ8】
2014年4月高等教育自学考试全国统一命题考试 英语（二）试题答案及评分参考 第一部分：阅读选择（第1-10题，每题1分，共10分） 1.A 2.B 3.C 4.A 5.C 6.A 7.B 8.C 9.B 10.A 第二部分：阅读判断（第11-15题，每题2分，共10分） 11.C 12.A 13.A 14.D 15.B 第三部分：概括段落大意和补全句子（第16-25题，每题1分，共10分）16.C 17.B 18.A 19.D 20.F 21.D 22.F 23.B 24.C 25.A 第四部分：填句补文（第26-30题，每题1分，共10分） 26.F 27.A 28.C 29.B 30.D 第五部分：填词补文（第31-40题，每题1分，共10分） 31.G 32.K 33.I 34.J 35.A 36.B 37.L 38.D 39.H 40.E
第六部分：完型补文（第41-50题，每题1.5分，共15分） 41.planned 42.thoughs 43.worried 44.longer 45.really 46.unclear 47.behviour 48.done 49.hidden 50.easily 绝密★启用前 2014年10月高等教育自学考试全国统一命题考试 英语（二）试题答案及评分参考 （课程代码00015） 第一部分：阅读判断（第1~10题，每题1分，共10分） 1、B 2、B 3、A 4、C 5、B 6、C 7、A 8、A 9、B 10、A 第二部分：阅读选择（第11~15题，每题2分，共10分） 11、D 12、A 13、C 14、B 15、A 第三部分：概括段落大意和补全句子（第16~25题，每题1分，共10分） 16、C 17、D 18、A 19、B 20、F 21、D 22、F 23、E 24、A 25、C
山东省2011年4月高等教育自学考试(自考)英语二试卷英语（二）试题（课程代码：00015 考试时间：150分钟） 注意事项： 答案必须写在答题卡规定的区域内，未按要求在作答的答案无效。 PART ONE (50 POINTS) I. Vocabulary and Structure (10 points, 1 point for each item) 在每小题列出的四个备选项中只有一个是符合题目要求的，请将其选出并将答题卡的相应代码涂黑。错涂、多涂或未涂均无分。 1. It is obvious to the students they should get well prepared for their future. A. as B. which C. whether D. that 2. Don’t worry if you don’t understand everything. The teacher will the main points at the end. A. recover B. review C. require D. remember 3. by the advances in technology, many farmers have set up wind farms on their land. A. Being encouraged B. Encouraging C. Encouraged D. Having encouraged 4. The art show was being a failure；it was a great success. A. far from B. along with C. next to D. regardless of 5. Ricky caught a cold yesterday, he had to stay at home. A. because B. but C. or D. so
考研化工原理试题库（下） 第一章蒸馏 一、选择题 1.当二组分液体混合物的相对挥发度为（）时，不能用普通精馏方法分离。 A.3.0 B.2.0 C.1.0 D.4.0 2.某精馏塔用来分离双组分液体混合物，进料量为100Kmol/h，进料组成为0.6 ,要求塔顶产品浓度不小于0.9，以上组成均为摩尔分率，则塔顶产品最大产量为（）。 A.60.5kmol/h B.66.7Kmol/h C.90.4Kmol/h D.不能确定 3.在t-x-y相图中，液相与气相之间量的关系可按（）求出。 A.拉乌尔定律 B.道尔顿定律 C.亨利定律 D.杠杆规则 4.q线方程一定通过x－y直角坐标上的点（）。 A.(xW,xW) B(xF,xF) C(xDxD) D(0,xD/(R+1)) 5.二元溶液的连续精馏计算中，进料热状态参数q的变化将引起（）的变化。 A.平衡线 B.操作线与q线 C.平衡线与操作线 D.平衡线与q线 6.精馏操作是用于分离（）。 A.均相气体混合物 B.均相液体混合物 C.互不相溶的混合物 D.气—液混合物 7.混合液两组分的相对挥发度愈小，则表明用蒸馏方法分离该混合液愈（）。 A容易；B困难；C完全；D不完全 8.设计精馏塔时，若Ｆ、xF、xD、xW均为定值，将进料热状况从q=1变为q>1，但回流比取值相同，则所需理论塔板数将（），塔顶冷凝器热负荷（），塔釜再沸器热负荷（）。A变大，B变小，C不变，D不一定 9.连续精馏塔操作时，若减少塔釜加热蒸汽量，而保持馏出量Ｄ和进料状况（F, xF,q）不变时，则L/V______ ，L′/V′______，x D______ ，x W______ 。 A变大，B变小，C不变，D不一定 10.精馏塔操作时，若Ｆ、x F、q，加料板位置、Ｄ和Ｒ不变，而使操作压力减小，则x D______，x w______。 A变大，B变小，C不变，D不一定 11.操作中的精馏塔，保持F，x F，q，D不变，若采用的回流比R< Rmin，则x D ______，x w______。 A变大，B变小，C不变，D不一定
2015年硕士研究生入学统一考试 英语二真题及答案 Section I Use of English Directions: Read the following text. Choose the best word(s) for each numbered blank and mark A, B, C or D on ANSWER SHEET. (10 points) In our contemporary culture, the prospect of communicating with -- or even looking at —a stranger is virtually unbearable. Everyone around us seems to agree by the way they fiddle with their phones, even without a 1 underground. It's a sad reality —our desire to avoid interacting with other human beings —because there's 2 to be gained from talking to the stranger standing by you. But you wouldn't know it, 3 into your phone. This universal armor sends the 4 : "Please don't approach me." What is it that makes us feel we need to hide 5 our screens? One answer is fear, according to Jon Wortmann, executive mental coach. We fear rejection, or that our innocent social advances will be 6 as "creepy,” We fear we'll be 7 . We fear we'll be disruptive. Strangers are inherently 8 to us, so we are more likely to feel 9 when communicating with them compared with our friends and acquaintances. To avoid this anxiety, we 10 to our phones. "Phones become our security blanket," Wortmann says. "They are our happy glasses that protect us from what we perceive is going to be more 11 .” But once we rip off the Band-Aid, tuck our smartphones in our pockets and look up, it doesn't 12 so bad. In one 2011 experiment, behavioral scientists Nicholas Epley and Juliana Schroeder asked commuters to do the unthinkable: Start a 13 . They had Chicago train commuters talk to their fellow 14 . "When Dr. Epley and Ms. Schroeder asked other people in the same train station to 15 how they would feel after talking to a stranger, the commuters thought their 16 would be more pleasant if they sat on their own," the New York Times summarizes. Though the participants didn't expect a positive experience, after they 17 with the experiment, "not a single person reported having been snubbed." 18 , these commutes were reportedly more enjoyable compared with those sans communication, which makes absolute sense, 19 human beings thrive off of social connections. It's that 20 : Talking to strangers can make you feel connected. 1. [A] ticket [B] permit [C] signal [D] record 2. [A] nothing [B] link [C] another [D] much 3. [A] beaten [B] guided [C] plugged [D] brought 4. [A] message [B] cede [C] notice [D] sign 5. [A] under [B] beyond [C] behind [D] from 6. [A] misinterpret [B] misapplied [C] misadjusted [D] mismatched 7. [A] fired [B] judged [C] replaced [D] delayed 8. [A] unreasonable [B] ungrateful [C] unconventional [D] unfamiliar 9. [A] comfortable [B] anxious [C] confident [D] angry 10. [A] attend [B] point [C] take [D] turn 11. [A] dangerous [B] mysterious [C] violent [D] boring 12. [A] hurt [B] resist [C] bend [D] decay