北京科技大学2012年《871工程热力学》考研专业课真题试卷

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《工程热力学》课程硕士研究生招生入学考试试题1

《工程热力学》课程硕士研究生招生入学考试试题1

《工程热力学》课程硕士研究生招生入学考试试题
考试科目名称:工程热力学
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南京航空航天大学《817工程热力学》历年考研真题汇编

南京航空航天大学《817工程热力学》历年考研真题汇编

目 录2011年南京航空航天大学817工程热力学考研真题2012年南京航空航天大学817工程热力学考研真题2013年南京航空航天大学817工程热力学考研真题2014年南京航空航天大学817工程热力学考研真题2015年南京航空航天大学817工程热力学考研真题2018年南京航空航天大学817工程热力学考研真题2011年南京航空航天大学817工程热力学考研真题南京航空航天大学2011年硕士研究生入学考试初试试题(A卷)科目代码:W满分:150分科目名称:工程热力学,主意:①认真阅读答题纸上的注意事项;②所有答案必酒写在查通上.写在本试题纸或草稿纸上均无效;③本试瞰须随瓠起建入试题袋中交回!二^简答「(共35分)1、〈5分〉某闭口系统细i呵逆过程f是奔能用温度的上升取下降来判断过程热缺文换为正、为负?若用靖参数的变化能否判断?2、<5分)绝热15流后流体烙估不变,所以黄流过程井不造演能咕品政下降,这种说法是杏正确,如何理解?3、{8分)若空气比热容取定值,间在定压加热过程中,夺气对外做功吊:和热力学能改变ht分别占加给空%热试的比例?空气觇为理想H体“4、〈7分)一个门锐打升的房间.若度内空气温度上升而斥力不变.取房间为开口热力系,村房内空'(的总热力学能At/如何变化<空气现为理慰'〔伸,比然容按定值计L5、(5分)可逆循坏的靖变为0,不可逆循环中而不可逆性的燃增.是否的以队为不叮逆循环的炳变大于0?简单解移城因,6、〈5分)燃气轮机定用加热理想循环中,当循环增温比t…定时,随循r环增压:比TT的捷*‘4循环热效率不断增大,口单位质量「.应在循环中辎出的仔功w倾也不断增大-判断这种说法是否正础.并简要解样.二、作图分析题(共20分}h(12分}某理想气体从同-初态分别纾过可逆绝热压缩1-2和不可逆绝热依缩1-2’过程,达到相同终压。

谓在T-$坐标图上分颓出两个过程的过程践,并在图中用面积表示出两过程的技术功以及不再逆过程的蛹损失,(环境温度为7;.K7;>7;)2、(8分)己钮房间内湿空I的露点温度q、湿球温度上,试在h-d|^t定性地确定湿空气的状态点”三、E5分}从七在初参数p,=600^a、勺=21V状态下秘定流入无运动部件的绝热容器.假定其中半依T〔在p Y=100通、2三愈,另外半氟'〔在p§=100打由、t r=-40。

北京理工大学管理与经济学院871管理学历年考研真题及详解专业课考试试题

北京理工大学管理与经济学院871管理学历年考研真题及详解专业课考试试题

2013年北京理工大学管理与经济学院管理 学(代码871)考研真题(回忆版)
北京理工大学2013年攻读硕士学位研究生入学考试试题 科目代码:871 科目名称:管理学 一、名词解释(共5题,每题4分) 1.激励 2.领导 3.决策 4.事业部 5.企业再造 二、选择题(共20题,每题2分) 题目比较灵活。
一般而言,以下三类企业需要进行再造工程:① 身陷困境、准备背水一 战的企业;② 目前经营状况尚好但有下降趋势的企业;③ 无论从近期 还是从长远看都处于极佳状态的企业。
二、选择题(共20题,每题2分) 题目比较灵活。
三、简答题(共5题,每题10分) 1.简述目标管理的特点和优点。 答:目标管理是一种以工作和人为中心的综合管理方法,它首先由 组织的上级管理人员与下级管理人员、员工一起制定组织目标,并由此 形成组织内每个成员的责任和分目标,明确规定每个成员的职责范围, 最后又用这些目标来进行管理、评价和决定对每一个部门和成员的奖 惩。 (1)目标管理的特点 ① 组织目标是共同商定的,而不是上级下达指标,下级提出保证; ② 根据组织的总目标决定每个部门和个人的任务、责任及应达到的 分目标; ③ 总目标和分目标是组织部门和个人的活动依据,一切活动都围绕 这些目标展开,将履行的职责和实现的目标紧密结合; ④ 将目标作为对部门和个人的考核依据。 (2)目标管理的优点 ① 目标管理可使工作具有明确的目标和方向,避免工作的盲目性和 随意性,避免形式主义和做无用功;
5.试析管理沟通的作用。 答:管理沟通的作用有以下几个方面: (1)收集信息,使决策更加合理和有效; (2)改善人际关系、稳定员工的思想情绪,统一组织行动; (3)通过有效的沟通,可以使组织成员的行为与组织要求趋于一致。 特别是在组织变革时期,通过沟通可以消除组织成员的抵触情绪,采取 合作态度; (4)沟通对组织成员的行为具有控制作用; (5)沟通是组织与外部环境联系的桥梁。

【北京科技大学2012年考研专业课真题】基础英语2012

【北京科技大学2012年考研专业课真题】基础英语2012

北京科技大学2012年硕士学位研究生入学考试试题============================================================================================================= 试题编号: 618 试题名称:基础英语(共 10 页)适用专业:外国语言文学(包括外国语言学及应用语言学和英语语言文学)说明:所有答案必须写在答题纸上,做在试题或草稿纸上无效;请用蓝色或黑色钢笔或签字笔答题。

=============================================================================================================Part Ⅰ Vocabulary (30 minutes, 30 points, 1 point each)Section ADirections:There are fifteen incomplete sentences in this section. For each sentence there are four choices marked A, B, C and D. Choose the ONE that best completes the sentence.1. No one appreciated his work during his lifetime, but it is clear that he was a great artist.A. in the aftermathB. by the timeC. in retrospectD. in this eventuality2. He was facing charges on forgery in a court of law but he hired a good attorney to .A. get offB. get throughC. get byD. get away3. The campers their tent in a sheltered valley.A. establishedB. installedC. pitchedD. fixed4. This is work. It calls for a good eye and a steady hand.A. preciseB. precisionC. exactD. exactness5. I’m rather concerned how he will take his school.A. onB. upC. offD. to6. I don’t doubt the plan will be well received.A. thatB. whichC. ifD. whether7. Over a very large number of trials, the probability of an event is equal to the probability that it will not occur.A. occurringB. occurredC. occursD. occur8. We will not be held responsible for any damage which results rough handling.A. fromB. offC. inD. to9. Now a single cell phone is able to store a large of information about an individual life.A. dealB. numberC. amountD. account10. The long service of decades of the to-be-retired with the company was a present each from the President.A. confirmed byB. recorded inC. acknowledged withD. appreciated for11. Buildings in the southeast of the UK are going to have to be constructed those in Scotland if the report findings are correct.A. asB. likeC. likelyD. are like12. We cannot see any possibility of business your price is on the high side of theprevailing market trend.A. whichB. sinceC. thatD. though13. If out successfully, the plan will completely change the traffic conditions in the city.A. carriedB. is carriedC. having been carriedD. to carry14. We are conscious of the extent work provides the psychological satisfaction that can make the difference between a full and empty life.A. to whichB. in whichC. at whichD. by which15. This book is about how these basic beliefs and values affect important of American life.A. fashionsB. frontiersC. facetsD. formatsSection BDirections:There are ten sentences in this section with one word or phrase underlined in each sentence. From the four choices given, choose one that best explains or defines the underlined part in each sentence.16. So engrossed in his efforts would Gaugin become that he barely noticed the passing of time.A. delighted inB. frustrated byC. expanded byD. involved in17. Rain abates in the fall throughout most of the Appalachian Mountain region.A. poursB. accumulatesC. lessensD. evaporates18. When a hurricane is about to occur, the National Weather Bureau issues a warning.A. adjacentB. giganticC. perilousD. imminent19. Relaxation therapy teaches one not to fret over small problems.A. worry aboutB. get involved inC. get angry aboutD. look for20. Mark Anthony’s eulogy of Caesar at his funeral is memorably recorded in a play by Shakespeare.A. prayerB. praiseC. biographyD. denunciation21. We regret being unable to entertain your request for providing free boarding to 15 sportsmen for two weeks.A. receiveB. complyC. coincideD. consider22. The ancient Jewish people regarded themselves as the salt of the earth, the chosen few by God to rule the world.A. outcastB. eliteC. nomadD. disciple23. Soon comics were so prevalent as to attract the attention of serious critics.A. successfulB. prosperousC. widespreadD. persuasive24. The progress of civilization itself can be measured by its range of mathematics.A. consideredB. decidedC. assessedD. found out25. The artist spent years on his monumental painting, which covered the whole roof of the church, the biggest in the country.A. archaicB. sentimentalC. outstandingD. entireSection CDirections:Each of the following five sentences below has two blanks, each blank indicating that something has been omitted. Beneath the sentence are four lettered sets of words. Choose the setof words for the blanks that best fit the meaning of the sentence.26. To list Reilly’s achievements in a fragmentary way is , for it distracts our attention from the themes of her work.A. unproductive … disparateB. misleading … integratingC. pragmatic … comprehensiveD. logical … important27. That many of the important laws of science were discovered during experiments designedto other phenomena suggests that experimental results are the of inevitable natural forces rather than of planning.A. analyze … foundationsB. disprove … predecessorsC. alter … adjunctsD. illuminate … consequence28. The availability of oxygen is an essential for animal life, while carbon dioxide is equally for plant life.A. choice … optionalB. duplication … selectiveC. conversion … exchangeableD. condition … necessary29. Old beliefs die hard: even when jobs became , the long-standing fear that unemployment could return at a moment’s notice .A. vacant … perishedB. easier … changedC. plentiful … persistedD. protected … subsided30. Politeness is not a attribute of human behavior, but rather a central virtue, one whose very existence is increasingly being by the faddish requirement to ―speak one’s mind.‖A. superficial … threatenedB. pervasive … undercutC. worthless … forestalledD. precious … affectedPart ⅡProofreading and error correction (20 minutes, 20 points, 2 points each) Directions: The following passage contains TEN errors. Each indicated line contains a maximum of ONE error. In each case, only ONE word is involved. You should proof-read the passage and correct it in the following way.For a wrong word, underline the wrong word and write the correct one in the blankprovided at the end of the line.For a missing word, mark the position of the missing word with a “∧‖ sign and writethe word you believe to be missing in the blank provided at theend of the line.For an unnecessary word, cross out the unnecessary word with a slash ―/‖ and put the wordin the blank provided at the end of the line.ExampleWhen∧art museum wants a new exhibit, 1. anit never buys things in finished form and hangs 2. neverthem on the wall. When a natural history museumwants an exhibition, it must often build it. 3. exhibitThe Consumer Price Index (CPI) is a measure of the averagechange over time in the prices paid by urban consumers for a marketbasket of consumer good and services. The CPI affects nearly all 1.Americans because of the many ways which it is used. Its three major 2.uses are: Firstly, as an economic indicator, the CPI is the most widelyused measurement of inflation and is sometimes viewed as an indicator 3.of the effectiveness of government economic policy. It providesinformations about price changes in the nation’s economy to 4.government, business, labor, and other private citizens, and is used bythem as a guide to make economic decisions. Secondly, as a deflator 5.of other economic series. The CPI and its components are used toadjusting other economic series for price changes and to translate 6.these series into inflation-free dollars. An interesting example ofthese is the use of the CPI as a deflator of the value of the consumer’s 7.dollar to find its purchasing power. The purchasing power ofthe consumer’s dollar measures the change in the value to the consumerof goods and services that a dollar will buy at different dates.By other words, as prices increase, the purchasing power of the 8.consumer’s dollar declines. Third, as a means of adjusting dollar 9.values. The CPI is often used to adjust consumer’s income payments; 10.to adjust income eligibility levels for government assistance;and to automatically provide cost-of-living wage adjustments tomillions of American workers.Part III Reading Comprehension (50 minutes, 40 points, 2 points each)Directions:There are four passages in this part. Read each passage carefully and answer the questions following each passage as you are required.Passage One―What does the middleman do but add to the price of goods in the shops?‖ Such remarks are aimed at the intermediate operations between manufactures and final customers. This practice usually attracts a lot of attention from the public and the press and the operation most talked about is what is often called wholesaling.The wholesaler buys goods in large quantities from the manufacturers and sells them in smaller parcels to retailers, and for this service his selling price to the retailer is raised several percent higher. But his job is made more difficult by retail demand not necessarily running level with manufacturers’production. Because he adjusts or regulates the flow of goods by holding stock until required, he frees the manufacturer, to some extent, from the effect on production of changing demand and having to bear the whole risk.The manufacturer can then keep up a steady production flow, and the retailer has no need to hold heavy stocks, who can call on the wholesaler for supplies any time. This wholesale function is like that of a valve in a water pipe. The middleman also bears part of the risk that would otherwise fall on the manufacturer and also the retailer.The wholesaler provides a purely commercial service, for which he is too well rewarded. But the point that is missed by many people is that the wholesaler is not just someone adding to the cost of goods. It is true one could eliminate the wholesaler but one would still be left with hisfunction: that of making sure that goods find their way to the people who want them.1. ―Middleman‖ in the passage almost equals to all the following in meaning except .A. go-betweenB. intermediaryC. manufacturerD. wholesaler2. The wholesaler obtains higher selling prices for .A. small parcels he sellsB. goods he buys in bulkC. the service he providesD. the information he offers3. A middleman’s work may become difficult because .A. manufactures run their production on a much higher levelB. market demand may not be the same as industrial productionC. retailers are not necessary in running their retailing businessD. retailers demand lower levels than those demanded by manufacturers4. What function of the wholesaler is compared to a valve?A. Controlling the flow of goods.B. Pushing up demand from retailers.C. Bearing part of the risk for manufacturers.D. Selling goods to retailers.5. The author quite possibly believes that the function of the wholesaler is .A. good but too costlyB. necessary but harmfulC. removable but necessaryD. acceptable but unnecessaryPassage TwoEvery group has a culture, however uncivilized it may seem to us. To the professional anthropologist, there is no intrinsic superiority of one culture over another, just as to the professional linguist, there is no intrinsic hierarchy among languages.People once thought of the languages of backward groups as undeveloped. While it is possible that language in general began as a series of grunts and groans, it is a fact established by the study of ―backward‖languages that no spoken tongue answers that description today. Most languages of uncivilized groups are, by our most severe standards, extremely complex. They differ from Western languages not in their sound patterns or grammatical structures, which usually are fully adequate for all language needs, but only in their vocabularies, which reflect the objects and activities known to their speakers. Even in this aspect, two things are to be noted. First, all languages seem to possess the machinery for vocabulary expansion, either by putting together words already in existence or by borrowing them from other languages and adapting them to their own system. Second, the objects and activities requiring names and distinctions in ―backward‖languages, while different from the West, are often surprisingly numerous and complicated. A Western language distinguishes merely between two degrees of remoteness (―this‖ and ―that‖ ) . But some languages of the American Indians distinguish between what is close to the speaker, or to the person addressed, or removed from both, or out of sight, or in the past, or in the future.6. Every group of human beings has .A. its own set of ideas, beliefs and ways of lifeB. an extremely complex and delicate languageC. its own elegant music, literature, and other artsD. the process of growing crops or raising animals7. To the professional linguists, .A. there is no intrinsic superiority of culturesB. there is no intrinsic hierarchy of languagesC. all languages came from grunts and groansD. all languages are most severe and standard8. According to this passage, to learn a foreign language would require one to .A. do more activitiesB. learn about a new cultureC. meet more peopleD. need more names9. The author’s attitude shown in this passage toward ―backward‖ languages is .A. restrainedB. subjectiveC. objectiveD. resolute10. This passage is on the whole .A. narrativeB. instructiveC. prescriptiveD. argumentativePassage ThreeIs test anxiety destructive? Can we make test anxiety work for us? The answer to both of these questions is yes. Test anxiety often interferes with student performance but this same test anxiety, if channeled correctly, can help improve performance.In order to lessen the destructive elements of test anxiety, the approach should be to develop improved confidence and knowledge. As your knowledge of the course material increases, your confidence in your ability to succeed will increase. As your confidence increases, your anxiety will go down, allowing your knowledge to come through more efficiently. The way you prepare for a test can reduce anxiety during the test.You will be surprised how confident you will feel if you know the material. Studies of memory show if you want to be able to recall information from text or lecture you have to review that material several times. It is important to know your own abilities and operate accordingly. If you know that you learn best by listening, prepare a tape of significant material and listen to the tape.Study partners or study groups are often useful for self-testing. Experience in stressful situations tends to lessen anxiety in those situations. One way to help yourself retrieve material is through the use of mnemonic codes. Learn a code that lets you remember complex material. Developing an outline for an essay question that you know will be on the test or memorizing a formula are forms of code development.Students are often frustrated by the sheer volume of material that has to be studied in college. Many instructors conduct reviews, give hints, identify what is important to study, use handouts or overhead transparency outlines. These materials should be at the top of your study list. If the instructor took the time to identify them, you should assume that they will play an important part of the test. While knowledge acquired during test preparation can help reduce anxiety, it is another thing to take the test itself. Following are a few suggestions to help reduce anxiety during the test.When I arrive at a test, I often find students flipping test pages at the last minute trying to cram it all in at the end. You would be better off trying to relax, meditating a little, and clearing your mind to allow yourself the ability to concentrate on the question that are coming.As soon as the instructor gives you the signal to start, dump out formulas, codes, outlines from your memory onto the test answer sheets so that you will not have to worry about whether you will remember the codes long enough until you get to the appropriate test question.You can build your confidence if you go through the test and answer all of the questions that you know first. Go back and work on those questions that need greater analysis, or that need to be worked out or need to be guessed at and your anxiety will not kick in until later in the test.For those of you whose anxiety increases as study and preparation increase, your goal should be to start concentrating on things that take your mind off the test, i.e., television, books, hobbies, movies, etc. Meditation and aerobic exercise have proven to be very useful methods for reducing undesirable effects of stress.The solution to reducing the destructive influences of stress is to plan to study. Map out a schedule of when you will study each day. Identify the specific topics that you will study each day. Identify the areas of the material that you have had problems with and study those. Your plan should include reading the text material, reviewing notes and homework assignments, identifying the material that needs further explanation, developing codes for memory material and testing yourself. Once you have studied adequately, your confidence will be fairly high, your knowledge will be satisfactory to do well on the test and the stomach butterflies will help you focus on the task at hand.I’d wish you good luck on finals, but you and I both know that the more effectively you study, the luckier you will get.11. Which of the following statements is NOT mentioned as a good side of the test anxiety?A. It can help improve performance if channeled correctly.B. It motivates us to study and prepare for exam.C. It can help us to concentrate.D. It can always ensure a good score in the test.12. Which of the following test preparation ways cannot help one reduce anxiety during the test?A. You should know your own abilities and operate accordingly and learn as much as you can.B. Study partners or study groups are useful for self-testing.C. You can retrieve materials by using mnemonic codes.D. You should pay more attention to the materials identified by the teacher.13. What should be at the top of your study list when you prepare a test?A. The most complex materials.B. The questions asked by students.C. The materials reviewed and hints given by the teacher.D. The materials mastered by most students.14. The suggestions to help reduce anxiety during the test are .A. relaxing, mnemonic codes and easy questions firstB. relaxing, dumping and easy questions firstC. relaxing, easy questions first and extreme anxietyD. aerobic exercise, relax and dumping15. According to the passage, useful means for reducing undesirable effects of stress are .A. knowledge and confidenceB. learning ability and instructor’s hintsC. meditation and aerobic exerciseD. rest and meditationPassage FourNo revolutions in technology have as visibly marked the human condition as those in transport. Moving goods and people, they have opened continents, transformed living standards, spread diseases, fashions and folk around the world. Yet technologies to transport ideas and information across long distances have arguably achieved even more: they have spread knowledge, the basis of economic growth.The most basic of all these, the written word, was already ancient by 1000. By then China had, in basic form, the printing press, using carved woodblocks. But the key to its future, movable metal type, was four centuries away. The Chinese were hampered by their thousands of ideograms. Even so, they quite soon invented the primitive movable type, made of clay, and by the 13th century they had the movable wooden type. But the real secret was the use of an easily cast metal.When it came, Europe –aided by simple Western alphabets –leapt forward with it. One reason why Asia’s civilizations, in 1000 far ahead of Europe’s, then fell behind was that they lacked the technology to reproduce and diffuse ideas. On Johannes Gutenberg’s invention in the 1440s were built not just the Reformation and the Enlightenment, but Europe’s agricultural and industrial revolutions too.Yet information technology on its own would not have got far. Literally: better transport technology too was needed. That was not lacking, but there the big change came much later: it was railways and steamships that first allowed the speedy, widespread dissemination of news and ideas over long distances. And both technologies in turn required people and organizations to develop their use. They got them: for individual communication. The postal service: for wider publics, the publishing industry.Throughout the 19th century, the postal service formed the bedrock of national and international communications. Crucial to its growth had been the introduction of the stamp, combined with a low price, and payment by the sender. Britain put all three of these ideas into effect in 1840.By then, the world’s mail was taking off. It changed the world. Merchants in America’s eastern cities used it to gather information, enraging far-off cotton growers and farmers, who found that the New Yorkers knew more about crop prices than they did. In the American debate about slavery, it offered abolitionists a low-cost way to spread their views, just as later technologies have cut the cost and widened the scope of political lobbying. The post helped too to integrate the American nation, tying the newly opened west to the settled east.Everywhere, its development drove and was driven by those of transport. In Britain, travelers rode by mail coach to posting inns. In America, the post subsidized road-building. Indeed, argues Dan Schiller, a professor of communications at the University of California, it was the connection between the post, transport and national integration that ensured that the mail remained a public enterprise even in the United States, its first and only government-run communications medium, and until at least the 1870s, the biggest organization in the land.The change has not only been one of speed and distance, though, but of audience. About 200 years ago, a man’s words could reach no further than his voice, not just in range but in whom they reached. But, for some purposes, efficient communication is mass communication, regular, cheap,quick and reliable. When it became possible, it transformed the world.16. According to the passage, which of the following statements is true?A. Transporting goods and people is the most important technology in the history of mankind.B. Technology in transporting goods and people has changed human conditions more than anything else.C. Technology in spreading information has changed human conditions more than transportation technology.D. Technology in spreading information can’t change the ec onomic development of society.17. Johannes Gutenberg’s invention probably refers to .A. printing technologyB. transportation technologyC. the Reformation and the EnlightenmentD. industrial revolution18. Which of the following statements is NOT true about the postal service?A. American abortionists were not happy about it.B. The stamp was invented in Britain.C. It helped the independence of America.D. In the 1840s it was the major means of national communications in Britain.19. In the United States, the postal service belongs to .A. a private companyB. the governmentC. road-building enterprisesD. national integration20. Which of the following statements is NOT true about mass communication?A. It can reach no further than human voice.B. It can reach a large audience.C. It is rapid and efficient.D. It can be trusted.Part ⅣTranslation (40 minutes, 30 points, 15 points each)Directions: There are two passages here. Put the underlined part in the first one into Chinese and the underlined part in the second one into English.[1] It may seem an exaggeration to say that ambition is something that can hold many of the society’s disparate elements together, but it is not an exaggeration by much. Remove ambition and the essential elements of society seem to fly apart. Ambition, as opposed to mere fantasizing about desires, implies work and discipline to achieve goals, personal and social, which society cannot survive without. Ambition is intimately connected with family, for men and women not only work for themselves, but partly for their families; husbands and wives are often ambitious for each other, but harbor some of their most ardent ambitions for their children. Yet to have a family nowadays —with birth control readily available, and inflation a good economic argument against having children — is nearly an expression of ambition in itself. Finally, though ambition was once the domain chiefly of monarchs and aristocrats, it has, in more recent times, increasingly become the domain of the middle class. Ambition and futurity —a sense of building for tomorrow —are inextricable. Working, saving, planning —these, the daily aspects of ambition —have alwaysbeen the distinguishing marks of a rising middle class. The attack against ambition is not incidentally an attack on the middle class and what it stands for.[2] 世界是千变万化的,疑问是层出不穷的,答案是丰富多彩的,对问题评述的标准不同,答案就不同。

北科大2011-2012学年度第二学期高等数学期中试卷

北科大2011-2012学年度第二学期高等数学期中试卷

北京科技大学2011--2012学年第二学期高 等 数 学AII 期中试卷院(系) 班级 学号 姓名 考场说明: 1、要求正确地写出主要计算或推导过程, 过程有错或只写答案者不得分; 2、考场、学院、班、学号、姓名均需写全, 不写全的试卷为废卷; 3、涂改学号及姓名的试卷为废卷;4、请在试卷上答题,在其它纸张上的解答一律无效.一、填空题(本题共36分,每小题4分)1. 设a x x a y D ≤≤-≤≤0,0:22(a 为正常数),由二重积分的几何意义知:⎰⎰=--Ddxdy y x a 222 .2. 设23(,,)23A x y z zi x j y k =++, 则=-)3,1,2(A. 3. 设),(y x f 具有一阶连续导数,且⎪⎪⎭⎫⎝⎛=z y y x f u ,,则d u =. 4. 累次积分⎰⎰⎰=x d f d d I 0)(ξηζζηξ 的定积分表达式为 .5. 函数32yz xy u +=在点(1,2,-1)处最大方向导数的值为 . 6. 设π32),(,5,2===b a b a,向量b a A 17+=λ与b a B-=3垂直,则=λ . 7. 设f 为可微函数, 222z y x r ++=, 则=)(grad r f .8. 设Ω是由221x y +=与0z =, 2z =所围成的圆柱体,则⎰⎰⎰Ω=+dv y x)(22.9. 设可微函数),(y x f 对任意实数)0(>t t 满足),(),(y x tf ty tx f =,而(1,2,2)P -是),(y x f z =上一点,且4)2,1(1=-'f ,则此曲面在点P 处的切平面方程为 .装 订 线 内 不 得 答 题 自觉遵 守 考 试 规 则,诚 信 考 试,绝 不作 弊二、选择题(本题共36分,每小题4分)10. 已知),(y x f 在点),(00y x 的偏导数存在,则 【 】.(A) ),(y x f 在点),(00y x 连续 (B)),(y x f 在点),(00y x 可微.(C) ),(0y x f 在点0x 连续 (D)),(y x f 在点),(00y x 有任意方向的方向导数. 11. 设有闭区域1:22≤+y x D , 则二重积分d Dx y 的值等于 【 】.(A)π53. (B) π43. (C) π76. (D) π83. 12. 设),(v u f 具有二阶连续偏导数,且),(22y x xy f z =,则=∂∂∂yx z 2 【 】. (A) 12222231132152222f y x f y x f xy f x yf ''+''+''+'+'.(B) 122222311315222f y x f y x f xy yf ''+''+''+'. (C) 1222223113212222f y x f y x f xy f x yf ''+''+''+'+'.(D) 1222221132152222f y x f xy f xy f x yf ''+''+''+'+'.13. 曲线0,6222=++=++z y x z y x 在点)1,2,1(-处的切线方程为【 】.(A)112211--=+=-z y x . (B) 210211-=+=-z y x . (C) 110211-=+=-z y x . (D) 110211--=+=-z y x . 14. 双紐线22222)(y x y x -=+所围成区域的面积可用定积分表示为【 】.(A) ⎰402cos 2πθθd . (B) ⎰402cos 4πθθd . (C) ⎰402cos πθθd . (D)⎰42cos 21πθθd .15. 设函数),(y x f 连续,则二次积分1sin 2d (,)d xx f x y y ππ=⎰⎰【 】.(A) 10sin d (,)d xy f x y x ππ+⎰⎰. (B)10arcsin d (,)d yy f x y x ππ-⎰⎰.(C)1arcsin 02d (,)d xy f x y x ππ+⎰⎰. (D)1arcsin 02d (,)d yy f x y x ππ-⎰⎰.16. 设⎰⎰⎰Ω=dudvdw w v u f z y x F ),,(),,(, 其中{}(,,),,u v w a u x b v y c w z Ω=≤≤≤≤≤≤,则=∂∂∂∂zy x F 3 【 】. (A) (,,)f u v w . (B) (,,)f x v w . (C) (,,)f x y w . (D) (,,)f x y z .17. 三次积分⎰⎰⎰---+++=2222)(302221)(y y yy y x dz z y x f dx dyI 写成球面坐标的形式为【 】.(A)⎰⎰⎰πϕθππϕϕθsin sin 02224)(sin dr r f r d d . (B)⎰⎰⎰πϕθππϕϕθsin sin 0224)(sin dr r f r d d .(C)⎰⎰⎰πϕθππϕϕθsin sin 02226)(sin dr r f r d d . (D)⎰⎰⎰πϕθππϕϕθsin sin 0226)(sin dr r f r d d .若两直线λ12111-=+=-z y x 与z y x =-=+11相交 ,则=λ 【 】. (A) 1. (B) 32. (C) 45-. (D) 45.三、解答题(本题共2小题,每题9分,满分18分)19. 设),(y x u 具有二阶连续偏导数,它满足关系式22220u u x y∂∂-=∂∂, x x x u =)2,(, 2)x =,求 )2,(),2,(2211x x u x x u '''' ,)2,(12x x u ''. 22y x z +=被平面1=++z y x 截成一椭圆,求原点到这椭圆的最长与最短距离.装 订 线 内 不 得 答 题 自 觉遵 守考 试 规 则,诚 信 考 试,绝 不作 弊四、证明题(本题共2小题,每题5分,满分10分)21. 设0)0(,1)0(=='f f ,连续)(u f ',且2222222()()d x y z t F t f x y z v ++≤=++⎰⎰⎰,证明:π54)(lim 5=+→tt F t .22. 设)(x f 在闭区间],[b a 上连续,利用二重积分性质证明:()22()d ()()d bbaaf x xb a f x x ≤-⎰⎰.。

北京科技大学研究生考试初试-871工程热力学大纲

北京科技大学研究生考试初试-871工程热力学大纲

考试科目名称:871工程热力学《工程热力学》考试大纲工程热力学课程是热能与动力工程、建筑环境与设备专业的一门重要技术基础课,它的教学目的与任务是:让学生学习关于能量守恒与转换的理论基础,使学生牢固地掌握工程热力学的基本理论、基本知识和相应的热工分析、计算能力,并进一步得到基本技能的训练。

为学习专业课提供充分的理论准备,也为学生以后解决生产实际问题和参加科学研究打下必要的理论基础。

其考试大纲内容如下:一、第一章基本概念要求熟练掌握:系统,平衡状态和状态参数,温度温标,压力,状态方程,准静态过程和可逆过程,循环,功和热量;透彻理解以下的基本概念:热力系统,热力学状态、平衡状态、准静态过程、可逆过程和不可逆过程、功与热量。

二、第二章热力学第一定律要求熟练掌握热力学第一定律基本表达式——基本能量方程,总能,热力学能,焓,膨胀功,技术功,热力学第一定律的第一解析式和稳定流动能量方程式及其应用,循环功之间及循环净功与循环净热量之间关系,循环热效率概念与计算公式;透彻理解以下概念:热力学第一定律的实质—能量守衡与转换定律在热现象中的应用,能量方程的内在联系与共性,热变功的实质。

会进行功和热量的计算,以及功和热量在p-v图和T-s图上的表示。

三、第三章气体和蒸汽的性质要求熟练掌握理想气体和实际气体的概念、理想气体状态方程、理想气体的比热容和热力学能、焓、熵的定义、计算;水蒸气的性质:水蒸气的饱和状态、饱和温度、饱和压力、饱和湿蒸汽、干度、三相点,水蒸气状态的确定。

四、第四章气体和蒸汽的基本热力过程要求熟练掌握理想气体的基本热力过程:定温、定压、定容、定熵和多变过程的过程方程、参数变化和过程中功及热量的计算及其p-v图和T-s图。

水的定压加热汽化过程及其在p-v图和T-s上的表示;会计算水蒸气定压过程的热量,水蒸气绝热过程的功。

五、第五章热力学第二定律熟练掌握热过程的方向性、热力学第二定律的表述;卡诺循环和卡诺定理、克劳修斯积分不等式、熵流和熵产、熵方程、孤立系统的熵增原理;作功能力、作功能力损失与熵产和火用平衡方程。

【北京科技大学2012年考研专业课真题】暖通空调2012

【北京科技大学2012年考研专业课真题】暖通空调2012

北京科技大学2012年硕士学位研究生入学考试试题============================================================================================================= 试题编号: 840 试题名称:暖通空调(共 5 页)适用专业:供热、供燃气、通风及空调工程说明:所有答案必须写在答题纸上,做在试题或草稿纸上无效。

=============================================================================================================一、单项选择题(共30分,每小题2分)1. 低温热水地板辐射采暖计算热负荷时,将室内温度取值降低2℃,是因为()。

A.相同热舒适条件下地板辐射采暖比对流采暖方式室温低2℃B.地板辐射采暖效率高C.地板辐射采暖散热面积大D.地板辐射采暖水温低2. 在确定采暖房间所需柱型散热器面积时,当散热器组装片数大于测试片数时,应乘以()的散热器组装片数修正系数。

A.小于1 B.1 C.大于1 D.小于等于13. 对被楼梯、扶梯、天井等贯通的房间,散热器应在()多放置。

A.底层B.顶层C.中间层D.任一层4. 带有混合水泵的直接连接热水供暖系统,若网路的设计供回水温度为130/70℃,供暖用户的设计供回水温度95/70℃,则混合水泵的设计混合比为()A.0.42 B.0.58 C.1.4 D.2.45. 按户计量的热水采暖系统,户内系统不宜采用()A.单管水平跨越式B.单管水平顺流式C.上供下回双管水平式D.下供下回双管水平式6. 确定空调房间围护结构的传热系数时,可以不考虑的因素是()。

A. 室内外温差、恒温精度B. 建筑物的用途和空调的类别C. 空调制冷系统的投资和运行费用D. 空调新风量7. 下列关于空调舒适性的说法中,哪一项是正确的?()A. 舒适性空调的目的就是使人舒适B. 夏天空调房间室内温度降低,人体舒适度将提高C. 室内新风量越大越好D. 长期生活在舒适的室内环境中对人体健康不利8. 下列关于空调冷负荷的说法中正确的是()。

北京科技大学历年高等代数考研真题汇编(2003-2017)

北京科技大学历年高等代数考研真题汇编(2003-2017)

九.(本题 20 分)设线性空间V W1 W2 L Ws ,证明:存在V 的线性变换1, 2 ,L , s
使得(1)

2 i
i
,1
i

s
;(2) i
j

0
,i

j ;(3)1 2 L
s I 为恒等变
换;(4) Im i Wi ,1 i s 。
1 ( 1,2,1,3 ),2 ( 1,1,2,1 ),3 ( 1,3,0,5 ), 1 ( 1,0,4,2 ), 2 ( 0,5,9,14 ) .
求(1)V1 的维数与一组基;(2)V2 的维数与一组基;(3)V1 V2 的维数 与一组基;(4)V1 V2 的维数与一组基.
注意:第一、二大题不必抄题,在答题纸上写清题号即可。
一.填空题(本题 20 分,每小题 4 分)
1. 已知 A 为 n 阶方阵且 A 3 ,则 A1 2 A*

2 . 设 A是 3 阶 可 逆 矩 阵 , A的 第 1 行 与 第 2 行 交 换 后 得 到 矩 阵 B, 则
AB1
一(15 分)、判断 f ( x ) x5 3x4 5x3 7 x2 6 x 2 有无重因式,若有,请求出 f (x)
的所有重因式并指出其重数.
1
二(20
分)、设矩阵
A


2 1
1 1 1
1
0 1

,
B

2

1
1 1
2 1
.
(1)计算矩阵 ABT 以及行列式 ABT BAT ;
-3-
北京科技大学 2012 年硕士学位研究生入学考试试题

【北京科技大学2012年考研专业课真题】水处理原理2012

【北京科技大学2012年考研专业课真题】水处理原理2012

北京科技大学2012年硕士学位研究生入学考试试题============================================================================================================= 试题编号: 856 试题名称:水处理原理(共 2 页)适用专业:环境科学与工程环境工程(专业学位)说明:所有答案必须写在答题纸上,做在试题或草稿纸上无效。

=============================================================================================================一、解释下列名词(30分,每个2分;答案按编号写在答题纸上,根据需要可以画草图表示)1、吸附平衡;2、MLSS;3、沉淀池表面负荷;4、平衡接触角;5、硝化过程;6、滤料的不均匀系数;7、氧转移动力效率Ep;8、臭阈值;9、TOC;10、聚合氯化铝;11、菌胶团;12、推流式活性污泥曝气池;13、污泥沉降比;14、反渗透的级;15、污泥膨胀二、填空(40分,每空1分; 答案按编号写在答题纸上)1、(3分)颗粒在液体中自由沉降时所受的三个力为:、、。

2、(5分)电解过程的影响因素主要如下:、、、、。

3、(3分)厌氧消化过程可划分为、和等三个阶段。

4、(4分)固定床式离子交换柱的交换过程一般包括、、和四个主要的步骤。

5、(3分)曝气的目的在于向活性污泥絮体和,使之处于状态,以提高处理效果。

6、(3分)按照污染物从废水中除去的方式,废水处理方法可分为处理、处理和处理三种。

7、(4分)中空纤维膜组件的两个优点是:、和(答出其中任意两个都可以),缺点之一是:或或(答出其中任何两个都可以)。

8、(8分)废水的分类:①根据废水来源:分为和;②根据废水中成分分为:、、;③根据废水中酸碱性分:、、。

北京科技大学2020年研究生入学考试计算机专业课871真题回忆

北京科技大学2020年研究生入学考试计算机专业课871真题回忆

计算机组成部分一、填空(10空10分)1.计算机能处理的语言是,编程用的语言中最接近机器语言的是2.n个Cache块,在组相联映射中,当组数为n和组数为1时分别变为和3.一组微命令构成,进而构成4.半导体随机存储器中SRAM的原理是DRAM的原理是5.定点加法运算器中无论采用双符号位还是单符号位,必须有,用来实现(王道2.2.4选择题)二、填空题(15题15分)1.若采用偶校验且校验无误,那么下列校验码中正确的是A.10010010B.10000010C.00101100D.010001012.(王道2.2.4)对真值0表示形式唯一的机器数是A.原码B.补码和移码C.反码D.以上都不对3.浮点数表示中,用移码表示阶码,用补码表示尾数,现在改为用补码表示阶码,那么所能表示的数的范围和之前相比A.变大B变小C不变D不能确定4.(王道3.1.3)下列各类存储器中,不采用随机存取方式的是A.EPROMB.CD-ROMC.DRAMD.SRAM5.(王道4.2.3)偏移寻址通过将某个寄存器内容与一个形式地址相加而生成有效地址。

下列寻址方式中,不属于偏移寻址的是A.间接寻址B。

基址寻址 C.相对寻址 D.变址寻址三、综合题(3个题,50分)中断屏蔽字如下图,(1)用原始的中断屏蔽字,中断响应次序是?中断处理次序是?(2)用更改后的中断屏蔽字,中断响应次序是?中断处理次序是?(3)画出用更改后的中断屏蔽字时的CPU执行程序图想要全部内容和历年真题可以联系我~数据结构部分:一、选择题(5个5分)1.元素以1,2,3,4,5的顺序入栈,下列是正确的出栈序列的是A.3 2 5 4 1B.1 5 2 3 4C.5 1 4 3 2D. 3 5 2 1 42.分析下面算法的时间复杂度for(i=1;i≤n;i*=2){Count++;}A.O(n)B.O(nlog2 n)C.O(n2)D.O(log2 n)3.(王道4.3.3)若二叉树中结点的先序序列是...a...b...,中序序列是...b...a....,则A.结点a和结点b分别在某结点的左子树和右子树中B.结点b在结点a的右子树中C.结点b在结点a的左子树中D.结点a和结点b分别在某结点的两棵非空子树中4.快速排序在最差情况下的时间复杂度是A.O(n)B.O(nlog2 n)C.O(n2)D.O(log2 n)5.一颗二叉树有100叶子结点,至少有多少个结点A.199B.200C.201D.202二、简答题(3个15分)1.如果一个序列基本有序那么用什么交换排序比较有效,为什么2.拓扑排序和关键路径能够解决什么问题3.构造Hash表三、代码题(3个50分)1.一个饭店老板和多个商人有交易往来,有的商人欠饭店的钱,老板又欠着另一些商人的钱,现在老板把这些帐的数值都记下来,如果是商人欠饭店的钱,就用正值来记,如果老板欠商人的钱就用负值来记,一共写了n个账目。

《工程热力学》课程考试模拟试卷

《工程热力学》课程考试模拟试卷

工程热力学》课程考试模拟试卷考试时间: 120 分钟姓名专业班级学号得分、判断题(正确的打√,错误的打×,每题 1 分,共10 分)1.容器中气体压力不变,则安装在其上面的压力表读数也不会变化。

2.系统由某一初态可逆变化到某一终态,在这确定的两个状态之间所有过程的膨胀功都相等。

3.理想气体绝热自由膨胀过程是等内能过程。

4.理想气体向真空膨胀体积由v1 变化到v2,熵的变化为s Rln v2v15.工质完成一个不可逆循环,其熵的变化量必大于零。

6.如果从同一初态出发到同一终态有两个过程,一个是可逆过程,一个是不可逆过程,那么不可逆过程的Δ s 必大于可逆过程的Δ s7.知道了温度和压力就可以确定水蒸气的状态。

8.含湿量相同的两种空气,温度高者吸湿能力强。

9.由饱和蒸汽压不同的两个组分形成的理想溶液达到相平衡时,易挥发组分在汽相中的相对含量大于它在液相中的相对含量。

10.温度为绝对零度时,任何物质的熵都是零。

、选择题(每题2分,共20分)1.若工质经历一可逆过程和一不可逆过程,且初态和终态相同,则两过程中工质与外界交换的热量A:相同 B :不同 C :无法确定2.下面叙述正确的是:A:自由膨胀为可逆过程B:混合过程是不可逆过程C:准静态过程是不可逆过程3.气体在某一过程中吸入了100kJ 的热量,同时内能增加了150kJ,该过程是A :膨胀过程B :压缩过程C :定容过程4. 一绝热刚体容器用隔板分成两部分。

一部分盛有高压理想气体, 另一部分为真空,抽去隔板后容器内的气体温度将: A :升高 B :不变 C :降低 5. 可逆定压稳定流动过程中,系统A :焓不变B :与外界交换的热量为零C :技术功为零 6. 一热机按某种循环工作,从温度为 T 1=2000K 的高温热源吸收热量1000KJ ,向温度为 T 2=300K 的冷源放热 1000KJ ,则该热机是A :可逆热机B :不可逆热机C :不可能热机 某理想气体由状态 1 经过不可逆绝热过程变化到状态 中工质熵的变化为: A :含湿量 B :相对湿度 C :干球温度10. 在 298K 、101325Pa 下有下列反应, Q 1, Q 2,Q 3在这几个热效应中 是标准生成焓的为:三、 简答、辩析与证明题(每题 5 分,共 20分)1 指出下列各式的适用条件:a) qdu wb) qdu pdvc)qh2vdp1d)wsh7. 2,该过程 8. 9. A : s 0 B12T q C : 2dT s cv 1 vT12Rd v v 压力升高,水的汽化潜热A :升高B :降低湿空气的压力一定时,其中水蒸汽的分压C :不变 A : CO B : 2H C :H 21O 2 CO 2 Q 12 O H 2O(g) Q 21e ) w c v (T 1 T 2)2 如果单级活塞式压气机采用了某种冷却方法可以实现等温压 缩,是否还有必要采用多级压缩?为什么? 3 简述稀溶液的四个依数性。

北京科技大学2014年硕士学位研究生入学考试试题-811热工原理

北京科技大学2014年硕士学位研究生入学考试试题-811热工原理

1 北 京 科 技 大 学2014年硕士学位研究生入学考试试题============================================================================================================= 试题编号:811 试题名称:热工理论 (包括传热传质学、工程热力学)(共3 页) 适用专业: 动力工程及工程热物理、供热、供燃气、通风及空调工程 、 动力工程(专业学位)说明:① 所有答案必须写在答题纸上,做在试题或草稿纸上无效。

② 考试用具:考生自带计算器=============================================================================================================工程热力学部分一、 概念题(每题3分,共15分)1、 准静态过程及判定条件2、 容积膨胀功、内部功、轴功、流动功、技术功及其关系3、 水蒸气的干度、过热度和汽化潜热4、 结露、结雾与结霜5、 相对湿度、绝对湿度和含湿量二、 判断下述说法对错,并简述理由(每题3分,共30分)1. 湿空气中的水蒸气常常处于过热状态或未饱和状态。

2. 系统经历了一个不可逆过程,已知终态熵小于初态熵,则该过程一定放出热量。

3. 对于任意一个过程,热力学第二定律对系统的要求是熵变大于等于0。

4. 理想气体在绝热容器中作自由膨胀,则气体温度与压力的表达式为。

5. 对于过热水蒸气,干度 。

6. 水蒸气在定温汽化过程前后温度不变(ΔT = 0 ),其热力学能也不变。

7. 工质经过一个不可逆循环有 。

8. 焓是在开口系统能量方程中推导得到的,因此在闭口系统中焓不存在。

9. 孤立系统熵增原理表明:过程进行的结果是孤立系统内各部分的熵都是增加的。

10. 由于绝热压缩过程不向外散热,故绝热压缩过程所消耗的压缩轴功最少。

沈维道《工程热力学》考研考点精讲

沈维道《工程热力学》考研考点精讲

考点精讲工程热力学考试指导及课程说明主讲:程老师沈维道《工程热力学》考研辅导课程1、沈维道《工程热力学》考点精讲及复习思路2、沈维道《工程热力学》名校真题解析及典型题精讲精练3、沈维道《工程热力学》冲刺串讲及模拟四套卷精讲本课程使用教材《工程热力学》第三版作者:沈维道,蒋智敏,童钧耕主编出版社:高等教育出版社出版时间:2001-6-1《工程热力学》第4版作者:沈维道,童钧耕主编出版社:高等教育出版社出版时间:2007-6-1《工程热力学》第4版作者:曾丹岺主编出版社:高等教育出版社出版时间:2002-12-1《工程热力学》作者:朱明善等编著出版社:清华大学出版社出版时间:2011-6-1《工程热力学》作者:冯青,李世武,张丽编著出版社:西北工业大学出版社出版时间:2006-9-1《工程热力学》(第三版)作者:华自强,张忠进编出版社:高等教育出版社出版时间:2000-7-1《工程热力学》第二版作者:毕明树、冯殿义、马连湘编出版社:化学工业出版社出版时间:2008-1-1《工程热力学》作者:朱明善等编著出版社:清华大学出版社出版时间:1995-7-1《工程热力学》第四版作者:华自强等编出版社:高等教育出版社出版时间:2009-11-1《工程热力学》(第五版)作者:廉乐明等编出版社:中国建筑工业出版社出版时间:2007-1-1《工程热力学》作者:王修彦主编出版社:机械工业出版社出版时间:2008-1-1《工程热力学》作者:严家騄,王永青编著出版社:中国电力出版社出版时间:2007-9-1考试分值分布一般来说,在硕士研究生入学考试中,工程热力学专业课满分为150分。

大家首先要认真仔细地阅读自己打算报考院校的招生简章,确定考试教材,然后阅读考试大纲,确认考试范围。

尤其是,要根据近年(一般三年内)的真题,了解分值的分布、题型,以及该院校出题的倾向和偏好。

考试分值分布考研的工程热力学试题,一般来说题型分为两大类:概念题和计算题。

北京科技大学2013年811 热工理论(含传热传质学、工程热力学)考研试卷

北京科技大学2013年811 热工理论(含传热传质学、工程热力学)考研试卷

北京科技大学2013年硕士学位研究生入学考试试题============================================================================================================= 试题编号: 811 试题名称:热工理论(含传热传质学、工程热力学)(共4 页)适用专业:动力工程及工程热物理、动力工程(专业学位)供热、供燃气、通风机空调工程说明:①所有答案必须写在答题纸上,做在试题或草稿纸上无效②考试用具:考生自带计算器、直尺=============================================================================================================一、选择题(每题1分,共10分)1. 如果热机从热源吸热100kJ,对外作功100kJ,则()。

(A)违反热力学第一定律;(B)违反热力学第二定律;(C)不违反第一、第二定律;(D)A和B。

2.系统在可逆过程中与外界传递的热量,其数值大小取决于()。

(A)系统的初、终态;(B)系统所经历的过程;(C)(A)和(B);(D)系统的熵变。

3.不断对密闭刚性容器中的汽水混合物加热之后,其结果只能是()。

(A)全部水变成水蒸汽(B)部分水变成水蒸汽(C)部分或全部水变成水蒸汽(D)不能确定4.()过程是可逆过程。

(A)可以从终态回复到初态的(B)没有摩擦的(C)没有摩擦的准静态过程(D)没有温差的5.湿蒸汽经定温膨胀过程后其内能变化()。

(A)△U = 0 (B)△U >0(C)△U<0 (D)△U<0或△U >06.多级(共Z级)压气机压力比的分配原则应是()。

(A)βi = (P Z+1 +P1)/ Z (B)βi = (P Z+1 / P1)1 / Z (C)βi = P Z+1/P1 (D)βi =(P Z+1 / P1)/ Z 7.工质熵减少的过程()。

北京科技大学2012年考研《材料科学与基础》

北京科技大学2012年考研《材料科学与基础》

北京科技大学2012年硕士学位研究生入学考试试题=============================================================================================================试题编号: 814 试题名称:材料科学基础(共 3 页)适用专业:材料科学与工程材料工程(专业学位) 说明:所有答案必须写在答题纸上,做在试题或草稿纸上无效。

=============================================================================================================一、简答题(8分/题,共40分)1. 写出七种晶系的名称及点阵参数之间的关系;2. 简述临界分切应力的概念;3. 给出一级相变和二级相变的分类原则和相变特征;4. 分析金属或合金的结晶形态;5. 给出再结晶温度的定义。

二、纯Cu晶体在常温下的点阵常数为a=0.3615nm:1. 指出其晶体结构类型和配位数(3分);2. 简略计算Cu原子半径、原子致密度和两类间隙半径(6分);3. 画出Cu原子在(111)晶面的分布情况,并计算其晶面间距和原子在晶面上的致密度(6分)。

(共15分)三、分别画出下列离子晶体的布拉菲点阵(下图中的点阵参数均为a=b=c,α=β=γ=90º)。

(10分)NaCl CaF2CaTiO3四、示意画出下面的Ti-Zr体系中bcc和hcp相在1155、1139、1000和878K 时的Gibbs自由焓-成分曲线。

(15分)五、根据下面的Al-Zn相图,1. 写出其中的三相反应式(4分);2. 画出x(Zn)=0.80合金的缓慢冷却曲线,并写出各阶段相对应的组织(8分);3. 画出上述合金缓慢冷却到室温时的组织示意图,并计算各组织组成物的相对含量(8分)。

《工程热力学》课程试卷.doc - 副本

《工程热力学》课程试卷.doc - 副本

《工程热力学》课程试卷一、是非(共12道题,每题1分,共12分)(对者√,错者×)1.公式d u = c v d t适用理想气体的任何过程。

()2.孤立系统的熵与能量都是守恒的。

()3.焓h = u + p v,对闭口系统,没有流动功,所以系统不存在焓这个参数。

()4.当压力超过临界压力,温度低于临界温度,则H2O处在液态。

()5.实际气体在压力趋于零的极限状态就成为理想气体。

()6.容器中气体的压力不变则压力表的读数也绝对不会改变。

()7.在T—S图上,任意二条可逆绝热过程线不能相交。

()8.再热循环的主要目的是提高汽轮机尾部排汽干度。

()9.热能利用系数完全地说明了热电循环的经济性能。

()10.阴雨天中由于空气中增加了水蒸汽量,所以大气压力增大了。

()11.膨胀功与流动功都是过程的函数。

()12.水蒸汽在绝热节流前后,其温度可以发生变化。

()二、选择(共13题,每题1分,共13分)13.压力为10 bar的气体通过渐缩喷管流入1 bar的环境中,现将喷管尾部截去一段,其流速、流量变化为()。

(A)流速减小,流量不变(B)流速不变,流量增加(C)流速不变,流量不变(D)流速减小,流量增大14.P V = R T描述了()的变化规律。

(A)任何气体准静态过程中(B)理想气体任意过程中(C)理想气体热力平衡状态(D)任何气体热力平衡状态15.某制冷机在热源T1= 300 K,及冷源T2= 250K之间工作,其制冷量为1000 KJ,消耗功为250 KJ,此制冷机是()。

(C)(A)可逆的(B)不可逆的(C)不可能的(D)可逆或不可逆的16.系统的总储存能为()。

(A)U (B)U + p V(C)(C)U + 122m c+m g z (D)U + p V +122m c+m g z17.卡诺定理表明:所有工作于同温热源与同温泠源之间的一切热机的热效率为()。

(A)(A)都相等,可以采用任何循环(B)(B)不相等,以可逆热机的热效率为最高(C)(C)都相等,仅仅取决与热源和泠源的温度(D)(D)不相等,与所采用的工质有关系18.通过叶轮轴对绝热刚性容器中的气体搅拌,其参数变化为()。

工程热力学 期末试题 答案

工程热力学 期末试题 答案

中北大学《工程热力学》期末题笔记:目标院校目标专业本科生笔记或者辅导班笔记讲义:目标院校目标专业本科教学课件期末题:目标院校目标专业本科期末测试题2-3套模拟题:目标院校目标专业考研专业课模拟测试题2套复习题:目标院校目标专业考研专业课导师复习题真题:目标院校目标专业历年考试真题,本项为赠送项,未公布的不送!中北大学 工程热力学 试题(A )卷(闭卷)2013--2014学年第 一 学期学号: 姓名:一、单项选择题(本大题共15小题,每题只有一个正确答案,答对一题得1分,共15分)1、压力为10 bar 的气体通过渐缩喷管流入1 bar 的环境中,现将喷管尾部截去一段,其流速、流量变化为。

【 】 A.流速减小,流量不变 B.流速不变,流量增加 C.流速不变,流量不变 D.流速减小,流量增大 2、某制冷机在热源T 1= 300K ,及冷源T 2= 250K 之间工作,其制冷量为1000 KJ ,消耗功为250 KJ ,此制冷机是 【 】A.可逆的B.不可逆的C.不可能的D.可逆或不可逆的 3、系统的总储存能为 【 】 A. U B. U pV +C. 2/2f U mc mgz ++D. 2/2f U pV mc mgz +++4、熵变计算式2121(/)(/)p g s c In T T R In p p ∆=-只适用于 【 】 A.一切工质的可逆过程 B.一切工质的不可逆过程 C.理想气体的可逆过程 D.理想气体的一切过程5、系统进行一个不可逆绝热膨胀过程后,欲使系统回复到初态,系统需要进行一个【】过程。

【 】A.可逆绝热压缩B.不可逆绝热压缩C.边压缩边吸热D.边压缩边放热6、混合气体的通用气体常数,【 】。

【 】A.与混合气体的成份有关B.与混合气体的质量有关C.与混合气体所处状态有关D.与混合气体的成份、质量及状态均无关系7、贮有空气的绝热刚性密闭容器中装有电热丝,通电后如取空气为系统,则【 】A.Q >0,△U >0,W >0 B.Q=0,△U >0,W >0 C.Q >0,△U >0,W=0 D.Q=0,△U=0,W=0 8、未饱和空气具有下列关系 【 】A.t>tw >tdB.t>td>tw.C.t = td = twD.t = tw>td9、绝热节流过程是【】过程。

北科大《工程热力学》作业 非热力专业

北科大《工程热力学》作业  非热力专业
7.
8.
第五章气体的热力性质
9.
10.
11.
第六章蒸气的热力性质
12.
1)点p=0.5MPa,T=360K的比容v,比焓h和比熵s。
2)点p=0.5MPa,h=300kJ/kg的温度T,比容v,干度x和比熵s.
13.
(查图题,答案略)
第七章蒸汽动力循环
无作业,学习课件例题。
第八章制冷循环
14.
1)空气进入冷藏室的温度;
《工程热力学》作业参考答案
第一章热力学绪论
1.锅炉烟道中的烟气压力常用上部开口的斜管测量,如图所示。若已知斜管倾角α=30°,压力计中使用ρ=0.8g/cm3的煤油,斜管中液柱长度L=200mm,当地大气压力Pb=0.1MPa,求烟气的绝对压力(用MPa表示)。
解:
2.某容器被一刚性壁分为两部分,在容器的不同部位安装有压力表,如图1-9所示。压力表B上的读数为75kPa,压力表C上的读数为0.11MPa。如果大气压力为97kPa,试确定压力表A上的读数,及容器两部分内气体的绝对压力。
2)每千克空气由冷藏室吸取的热量;
3)循环消耗的净功;
4)循环的制冷系数。
《传热学》作业参考答案第Leabharlann 章导热15.16.
第二章对流换热
17.
18.
第三章辐射换热
19.
20.
第四章传热
21.
22.
3.把CO2压送到体积为3m3的贮气罐里,气罐内起始表压力pe1=30kPa,终了时表压力pe2=0.3MPa,温度由t1=45°C增加到t2=70°C。试求被压入的CO2的质量。当时当地的大气压pb=0.1MPa。
解:
第二章热力学第一定律
1.
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1 北 京 科 技 大 学
2012年硕士学位研究生入学考试试题
============================================================================================================= 试题编号: 871 试题名称: 工程热力学 (共 3 页)
适用专业: 动力工程及工程热物理、动力工程 (专业学位) 说明: 所有答案必须写在答题纸上,做在试题或草稿纸上无效。

=============================================================================================================
一、 判断是非题(每题1分,共15分)
1、 理想气体自由膨胀后熵增加。

( )
2、 闭口系统中发生放热过程,熵必减少。

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3、 工质放热,其熵不一定减少。

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4、 在相同热源间工作的一切热机,不论采用什么工质,其热效率均相同。

( )
5、 热源与冷源的温差越大,热效率越高,制冷系数也越大。

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6、 气体吸热一定膨胀作功。

( )
7、 流动功的大小仅取决于系统的进口和出口状态,而与经历的过程无关。

( )
8、 理想气体不可能进行放热而升温过程。

( )
9、 在压缩蒸汽制冷循环中,所选用的制冷剂液体比热越小,那么节流过程引起的损失就越小。

( )
10、 稳定流动能量方程不适用于有摩擦的情况。

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11、 用两个独立的状态参数就能确定混合气体的热力状态。

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12、 湿空气的相对湿度可用干-湿球温度计间接测量。

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13、 开口系统的质量一定是变化的。

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14、 闭口系统经过一个不可逆过程,其熵变化一定大于零。

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15、 回热循环的热效率比朗肯循环高,但比功比朗肯循环低。

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二、 名词解释(每题4分,共20分)
1. 理想气体与实际气体
2. 多变过程与多变指数
3. 热力学能与热量
4. 绝对湿度与相对湿度
5. 饱和湿蒸气与饱和湿空气
三、填空题(每题4分,共20分)
1、 提高动力(热机)循环热效率的途径,理念上最终可以归纳为两条:__ ___________________________和_________________________________
2、 已知某理想气体的()K kg kJ C p ⋅=866.01000;()K kg kJ C p ⋅=910.02000,。

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