2004年研究生入学试题(A)

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2004年全国硕士研究生入学统一考试

2004年全国硕士研究生入学统一考试西医综合科目试题一、A型题：共92个小题，每小题1分，共92分。

在每小题给出的A、B、C、D、E五个选项中，只有一项是最符合试题要求的。

1.维持内环境稳态的重要调节方式是A.负反馈调节B.自身调节C.正反馈调节D.体液性调节E.前馈调节2.细胞膜内外正常Na+和K+浓度差的形成和维持是由于A.膜安静时K+通透性大B.膜兴奋时Na+通透性增加C.Na+易化扩散的结果D.膜上Na+泵的作用E.膜上Ca2+泵的作用3.运动神经纤维末稍释放ACh属于A.单纯扩散B.易化扩散C.主动转运D.出胞作用E.入胞作用4.与肠黏膜细胞吸收葡萄糖关系密切的转运过程是A.HCO3-的被动吸收B.Na+的主动吸C.K+的主动吸收D.C1-的被动吸收E.Ca2+的主动吸收5.肝素抗凝血的主要作用机理是A.抑制X因子激活B.增强抗凝血酶Ⅲ的活性C. 去除Ca2+D 促进纤维蛋白溶解E.抑制血小板的作用6.心细胞有效不应期特别长的生理意义是A.使心肌不发生强直性收缩B.使心肌“全或无”式收缩C.使心肌收缩更有力D.使心肌产生自动节律性兴奋E. 使心肌同步收缩7.CO2在血液是运输的主要形式是A.物理溶解B.H2CO3C.HCO3-D.HbNHCOOHE.HbCO28.肺通气的原动力是A.气体分压大小B.肺内压变化C.胸内压变化D.肺本身的舒缩活动E.呼吸肌的舒缩活动9.下列关于消化道平滑肌基本电节律的叙述,错误的是A.是指节律性去极化波B.又称慢波电位C.其产生不依赖于神经的存在D.节律不受神经和激素的影响E.浓缩在10mV-15mV之间K刺激胰液分泌的特点是A.水分少,HCO3-和酶含量多B.水分和HCO3-含量少,酶含量多C.水分和HCO3-含量多,酶含量少D.水分多,HCO3-和酶含量少E.水分、HCO3-和酶含量都多11.下列物质中,食物的特殊动力作用最强的是A.糖B.脂肪C.蛋白质D.维生素E.无机盐12.听觉感受器官位于A.耳蜗B.鼓膜C.半规管D.椭圆囊E.球囊13.下列关于视杆细胞的叙述,错误的是A.不能产生动作电位B.能产生感受器电位C.视敏度高D.光敏度高E.司暗视觉14.原尿在肾脏被生吸收的比率为A.67%B.85%C.89%D.95%E.99%15.下列哪种激素与水、钠代谢无关?A.氯化可的松B.醛固酮C.雌激素D.胰高血糖素E.抗利尿激素16.排卵后形成的黄体可分泌的激素是A.黄体生成素B.卵泡刺激素C.促进腺激素释放激素D.人绒毛膜生长素E.孕激素和雌激素17.睾丸间质细胞的生理功能是A.分泌雄激素B.营养和支持生殖细胞C.起血睾屏障作用D.产生精子E.分泌雄激素结合蛋白18.兴奋性突触后电位的电变化是A.极化B.去极化C.超极化D.反极化E.复极化19.含有两个氨基的氨基酸是A. LyaB.TrpC.ValD.GluE.Leu20.下列DNA双螺旋结构的叙述,正确的是A.一条链是左手螺旋,另一条链是右手螺旋B.双螺旋结构的稳定纵向靠氢键维系C.A+Y与G+C的比值为1D.两条链的碱基间以共价键相连E.磷酸、脱氧核糖构成螺旋的骨架21.磺胺类药物能竞争性抑制二氢叶酸还原酶是因为其结构相似于A.对氨基苯甲酸B.二氢蝶呤C.苯丙氨酸D.谷氨酸E.酪氨酸22.供氧不足时,3-磷酸甘油醛脱氢产生的NADH+H+的主要去路是A.参加脂肪酸的合成B.使丙醋酸还原生成乳酸C.维持GSH处于还原状态D.经α-磷酸甘油穿梭进入线粒体氧化E.经苹果酸-天冬氨酸穿梭进入线粒体氧化23.下列不参与糖异生作用的酶是A.丙酮酸羟化酶B.磷酸烯醇式丙酮酸羟激酶C.果糖双磷酸酶-1D.葡萄糖-6-磷酸酶E.6-磷酸果糖激酶-124.合成商磷脂需要的物质是A.CDP-乙醇胺B.CDP-胆碱C.UDP-胆碱D.UDP-乙醇胺E.GOP-乙醇胺25.合成嘌呤、嘧啶的共用原料是A.甘氨酸B.一磷单位C.谷氨酸D.天冬氨酸E.氨基甲酰磷酸26.脑中氨的主要去路是A.扩散入血B.合成尿素C.合成嘌呤D.合成氨基酸E.合成谷氨酰胺27.下列关于变构酶的叙述,错误的是A.变构酶催化非平衡反应B.多为代谢途径的关键酶C.与变构效应剂呈可逆结合D.都具有催化亚基和调节亚基E.酶构象变化后活性可升高或降低28.下列因子中,不参与原核生物翻译过程的是A.IFB.EF1C.EFTD.RFE.RR29.下列关于复制和转录过程异同点的叙述,错误的是A.复制和转录的合成方向均为5’→3’B.复制和转录过程均需以RNA为引物C.复制的原料dNTP,转录的原料为NTPD.二者的聚合酶均催化形成3’,5’磷酸二酯键E.DNA的双股链中只有一条链转录,两条链均可被复制30.直接影响细胞内cAMP含量的酶是A.磷脂酶B.蛋白激酶AC.腺背酸环化酶D.蛋白激酶CE.酪氨酸蛋白激酶31.能识别DNA特异序列并在识别位点或其周围切割双链DNA的一类酶是A.核酸外切酶B.核酸内切酶C.限制性核酸外切酶D.限制性核酸内切酶E.核酸末端转移酶32.真核生物RNA聚合酶1转录后可产生的是A.huRNAB.45S-rRNAC.t RNAD.5S-rRNAE.snRNA33.转移性钙化可发生于A.血栓B.肾小管C.干酪样坏死D.粥瘤E.死亡血吸虫卵34.与化生相关的癌是A.食管鳞癌B.皮肤鳞癌C.子宫颈鳞癌D.膀胱鳞癌E.阴茎鳞癌35.主要由纤维蛋白构成的血栓是A.透明血栓B.红色血栓C.混合血栓D.白色血栓E.附壁血栓36.产物为生长因子受体的癌基因是A.rasB.sisC.mycD.cydinDE.erb-B237.与DNA修复调节基因突变相关的肿瘤是A.遗传性非息肉病性大肠癌B.家族性腺瘤性息肉病C. Li-Fraumeni综合症D.神经纤维瘤病E.肾母细胞瘤38.造成动脉粥样硬化病灶中纤维增生的主要细胞是A.内皮细胞B.泡沫细胞C.平滑肌细胞D.纤维母细胞E.淋巴细胞39.非典型肺炎属于A.肺化脓性炎B.肺纤维素性炎C.肺泡性炎D.肺间质性炎E.肺出血性炎40.无淋巴结转移的癌是A.早期食管癌B.早期胃癌C.早期大肠癌D.肺鳞癌E.胰腺癌41.缺乏典型诊断性R-S细胞的霍奇金淋巴瘤亚型是A.结节硬化型B.混合细胞型C.淋巴细胞减少型D.弥漫性淋巴细胞为主型E.结节性淋巴细胞为主型42.致密沉积物病属于下列哪种肾小球肾炎?A.膜性肾小球肾炎B.快速进行性肾小球肾炎C.系膜增生性肾小球肾炎D.膜性增生性肾小球肾炎E.毛细血管内增生性肾小球肾炎43.下列关于梅毒树胶肿的叙述,正确的是A.大片酷样坏死B.类上皮细胞丰富C.大量郎罕巨细胞D.淋巴细胞、浆细胞少见E. 可见原有血管壁轮廓44.下列关于Kaposi肉瘤的叙述,正确的是A.来源于纤维组织的恶性肿瘤B.仅累及皮肤C.肿瘤边界清楚D.是由梭形细胞和血管构成的恶性肿瘤E. 80%以上艾滋病患者受累45.下列属于非浸润性乳腺癌的是A.粉刺癌B.黏液癌C.小管癌D.髓样癌E.硬癌46.皮肤活检时,SLE最典型的发现是A.真皮浅表部出血B.真皮深部出血C.真皮内色血素沉积D.真皮深部免疫复合物沉积E.真皮浅表部免疫复合物沉积47.下列关于心力衰竭概念的叙述,错误的是A.心排血量可维持正常B.通常伴有肺循环的主动充血C.是指伴有临床症状的心功能不全D.有心功能不全不一定有心力衰竭E.伴有体循环充血的心衰称为充血性心力衷竭48.关于心力衰竭时各种体液因子的改变,下列哪项正确?A.心衰时,缓激肽生成增加B.缓激肽有很强的利尿作用C.心衰早期,心钠素分泌减少D.内皮依赖性释放因子有强大的缩血管作用E.由于心排血量降低,引起血管加压素分泌减少49.下列符合心电图诊断窦性停搏的是A.心室率小于40次/分B.可见单个逸搏或逸搏心律C.长PP间期的时间大于1.5秒D.长PP间期与基本的窦性PP 间期无倍数关系E.PP间期进行性缩短,直到出现一次长PP间期50.男性,68岁,持续性心房颤动史10年,长期服用洋地黄、硫氮草酮，10天前腹泻伴恶心、食欲下降。

全国硕士研究生入学统一考试英语真题2004年

全国硕士研究生入学统一考试英语真题2004年(总分：80.00，做题时间：90分钟)一、{{B}}Section Ⅰ Listening Comprehension{{/B}}(总题数：20，分数：10.00)A.actingB.relyingC.centering √D.cemmenting解析：[试题分析] 这是一个同义短语理解和语法修饰题。

[详细解答] 本题即词汇复现。

focus on和center on是同义的动词短语。

意为“关注；强调”。

第一句总说，然后分说；但句式相同，“Theories”后现在分词作后置定语。

A.beforeB.unlessC.untilD.because √解析：[试题分析] 这是一个篇章照应和连词运用题。

[详细解答] 本题为前后照应。

强调个体的理论理由是为什么呢?显然应给出理由。

所以用because。

A.interactions √B.assimilationC.cooperationD.consultation解析：[试题分析] 这是一个短语搭配题。

[详细解答] 本题为前后照应题。

根据learn sth. through以及后面和with others搭配，很容易得出interactions。

A.returnB.replyC.referenceD.response √解析：[试题分析] 这是一个短语搭配题。

[详细解答] 本题为前后照应题。

根据句意，再加上in... to 的结构，同样不难选出正确答案。

A.or √B.but ratherC.butD.or else解析：[试题分析] 这是一个篇章发展技巧和连词运用题。

[详细解答] 它与本文第二句话的行文模式相同，也很容易选出or。

A.consideringB.ignoring √C.highlightingD.discarding解析：[试题分析] 这是一个篇章照应和词语辨析题。

[详细解答] 本题为前后照应。

2004年全国考研英语试题及答案.doc

2004年全国硕士研究生入学统一考试英语试题Section II Use of EnglishDirections:Read the following text. Choose the best word (s) for each numbered blank and mark [A], [B], [C] or [D] on ANSWER SHEET 1. (10 points)Many theories concerning the causes of juvenile delinquency (crimes committed by young people) focus either on the individual or on society as the major contributing influence. Theories 大21家on the individual suggest that children engage in criminal behavior 大22家they were not sufficiently penalized for previous misdeeds or that they have learned criminal behavior through 大23家with others. Theories focusing on the role of society suggest that children commit crimes in 大24家to their failure to rise above their socioeconomic status, 大25家as a rejection of middle-class values.Most theories of juvenile delinquency have focused on children from disadvantaged families, 大26家the fact that children from wealthy homes also commit crimes. The latter may commit crimes 大27家lack of adequate parental control. All theories, however, are tentative and are 大28家to criticism.Changes in the social structure may indirectly 大29家juvenile crime rates. For example, changes in the economy that 大30家to fewer job opportunities for youth and rising unemployment 大31家make gainful employment increasingly difficult to obtain. The resulting discontent may in 大32家lead moreyouths into criminal behavior.Families have also 大33家changes these years. More families consist of one-parent households or two working parents; 大34家, children are likely to have less supervision at home 大35家was common in the traditional family 大36家. This lack of parental supervision is thought to be an influence on juvenile crime rates. Other 大37家causes of offensive acts include frustration or failure in school, the increased 大38家of drugs and alcohol, and the growing 大39家of child abuse and child neglect. All these conditions tend to increase the probability of a child committing a criminal act, 大40家 a directcausal relationship has not yet been established.21. [A] acting[B] relying[C] centering[D] commenting22. [A] before[B] unless[C] until[D] because23. [A] interaction[B] assimilation[C] cooperation[D] consultation24. [A] return[B] reply[C] reference[D] response25. [A] or[B] but rather[C] but[D] or else26. [A] considering[B] ignoring[C] highlighting[D] discarding27. [A] on[B] in[C] for[D] with28. [A] immune[B] resistant[C] sensitive[D] subject29. [A] affect[B] reduce[C] check[D] reflect30. [A] point[B] lead[C] come[D] amount31. [A] in general[B] on average[C] by contrast[D] at length32. [A] case[B] short[C] turn[D] essence33. [A] survived[B] noticed[C] undertaken[D] experienced34. [A] contrarily[B] consequently[C] similarly[D] simultaneously35. [A] than[B] that[C] which[D] as36. [A] system[B] structure[C] concept[D] heritage37. [A] assessable[B] identifiable[C] negligible[D] incredible38. [A] expense[B] restriction[C] allocation[D] availability39. [A] incidence[B] awareness[C] exposure[D] popularity40. [A] provided[B] since[C] although[D] supposingSection III Reading ComprehensionPart ADirections:Read the following four texts. Answer the questions below each text by choosing [A], [B], [C] or [D]. Markyour answers on A NSWER SHEET 1. (40 points)Text 1Hunting for a job late last year, lawyer Gant Redmon stumbled across CareerBuilder, a job database onthe Internet. He searched it with no success but was attracted by the site’s “personal se interactive feature that lets visitors key in job criteria such as location, title, and salary, then E-mails themlegal, intellectual property,when a matching position is posted in the database. Redmon chose the keywordsand Washington, D.C. Three weeks later, he got his first notification of an open ing. “I struck g old,” says Redmon, who E-mailed his resume to the employer and won a position as in-house counsel for a company.With thousands of career-related sites on the Internet, finding promising openings can betime-consuming and inefficient. Search agents reduce the need for repeated visits to the databases. B ut although a search agent worked for Redmon, career experts see drawbacks. Narrowing your criteria, for example, may work against you: “Every time you answer a question you eliminate a possibility.expert.For any job search, you should start with a narrow concept—what you think you want to do -- then broaden it. “None of these programs do that,” says another expert. “There’s no career coe best strategy is to use the agent as a kind of tip service to keep abreast of jobs in aall of this.” Instead, thparticular database; when you get E-mail, consider it a reminder to check the database again. “rely on agents for finding everything that is added to a da tabase that might interest me,” says the author job-searching guide.agent sends out Some sites design their agents to tempt job hunters to return. When CareerSite’smessages to those who have signed up for its service, for example, it includes only three potential jobs --those it considers the best matches. There may be more matches in the database; job hunters will have tovisit the site again to find them -- and they do. “On the day after we send our messages, we see a sharp increase in our traffic,” says Seth Peets, vice president of marketing for CareerSite.Even those who aren’t hunting for jobs may find search agents worthwhile. Some use them to keep a close watch on the demand for their line of work or gather information on compensation to arm themselveswhen negotiating for a raise. Although happily employed, Redmon maintains his agent at CareerBuilder. “You always keep your eyes open,” he says. Working with a personal search agent means having anoth of eyes looking out for you.41. How did Redmon find his job?[A] By searching openings in a job database.[B] By posting a matching position in a database.[C] By using a special service of a database.[D] By E-mailing his resume to a database.42. Which of the following can be a disadvantage of search agents?[A] Lack of counseling.[B] Limited number of visits.[C] Lower efficiency.[D] Fewer successful matches.43. The expression “tip service” (Line 4, Paragraph 3) most probably means ________.[A] advisory[B] compensation[C] interaction[D] reminder44. Why does CareerSite’s agent offer each job hunter only three job options?[A] To focus on better job matches.[B] To attract more returning visits.[C] To reserve space for more messages.[D] To increase the rate of success.45. Which of the following is true according to the text?[A] Personal search agents are indispensable to job-hunters.[B] Some sites keep E-mailing job seekers to trace their demands.[C] Personal search agents are also helpful to those already employed.[D] Some agents stop sending information to people once they are employed.Text 2Over the past century, all kinds of unfairness and discrimination have been condemned or made illegal.But one insidious form continues to thrive: alphabetism. This, for those as yet unaware of such a disadvantage, refers to discrimination against those whose surnames begin with a letter in the lower half ofthe alphabet.It has long been known that a taxi firm called AAAA cars has a big advantage over Zodiac cars when customers thumb through their phone directories. Less well known is the advantage that Adam Abbott has inlife over Zo?Zysman. English names are fairly evenly spread between the halves of the alphabet. Yet a suspiciously large number of top people have surnames beginning with letters between A and K.Thus the American president and vice-president have surnames starting with B and C respectively; and26 of George Bush’s predecessors (including his father) had surnames in the first half of the alphabet agains just 16 in the second half. Even more striking, six of the seven heads of government of the G7 rich countriesare alphabetically advantaged (Berlusconi, Blair, Bush, Chirac, Chrétien and Koizumi). The world’top central bankers (Greenspan, Duisenberg and Hayami) are all close to the top of the alphabet, even if oneof them really uses Japanese characters. As are the world’s five richest men (Gates, Buffett, Alle and Albrecht).Can this merely be coincidence? One theory, dreamt up in all the spare time enjoyed by the alphabetically disadvantaged, is that the rot sets in early. At the start of the first year in infant school, teachers seat pupils alphabetically from the front, to make it easier to remember their names. Soshort-sighted Zysman junior gets stuck in the back row, and is rarely asked the improving questions posedby those insensitive teachers. At the time the alphabetically disadvantaged may think they have had a lucky escape. Yet the result may be worse qualifications, because they get less individual attention, as well as less confidence in speaking publicly.The humiliation continues. At university graduation ceremonies, the ABCs proudly get their awardsfirst; by the time they reach the Zysmans most people are literally having a ZZZ. Shortlists for job interviews, election ballot papers, lists of conference speakers and attendees: all tend to be drawn upalphabetically, and their recipients lose interest as they plough through them.46. What does the author intend to illustrate with AAA A cars and Zodiac cars?[A] A kind of overlooked inequality.[B] A type of conspicuous bias.[C] A type of personal prejudice.[D] A kind of brand discrimination.47. What can we infer from the first three paragraphs?[A] In both East and West, names are essential to success.[B] The alphabet is to blame for the failure of Zo? Zysman.[C] Customers often pay a lot of attention to companies’ names.[D] Some form of discrimination is too subtle to recognize.48. The 4th paragraph suggests that ________.[A] questions are often put to the more intelligent students[B] alphabetically disadvantaged students often escape from class[C] teachers should pay attention to all of their students[D] students should be seated according to their eyesight-3, Paragraph 5)?49. What does the author m ean by “most people are literally having a ZZZ” (Lines 2[A] They are getting impatient.[B] They are noisily dozing off.[C] They are feeling humiliated.[D] They are busy with word puzzles.50. Which of the following is true according to the text?[A] People with surnames beginning with N to Z are often ill-treated.[B] VIPs in the Western world gain a great deal from alphabetism.[C] The campaign to eliminate alphabetism still has a long way to go.[D] Putting things alphabetically may lead to unintentional bias.Text 3-year-old When it comes to the slowing economy, Ellen Spero isn’t biting her nails just yet. But the 47 manicurist isn’t cutting, filling or polishing as many nails as she’d like to, either. Most of $12 to $50 weekly, but last month two longtime customers suddenly stopped showing up. Spero blames thea good economic indicator,”　she says. “I provide a service that people can do softening economy. “I’mSo Spero is downscaling, shopping at without when they’re concerned about saving some dollars.”　middle-brow Dillard’s department store near her suburban Cleveland home, instead of Neiman Marcus. don’t know if other clients are going to abandon me, too.” she says.-hot economy is cooling, lots of working Even before Alan Greenspan’s admission that America’s redfolks had already seen signs of the slowdown themselves. From car dealerships to Gap outlets, sales havebeen lagging for months as shoppers temper their spending. For retailers, who last year took in 24 percent of their revenue between Thanksgiving and Christmas, the cautious approach is coming at a crucial time. Already, experts say, holiday sales are off 7 percent from last year’s pace. But don’t s yet. Consumers seem only mildly concerned, not panicked, and many say they remain optimistic about the economy’s long-term prospects, even as they do some modest belt-tightening.Consumers say they’re not in despair because, despite the dreadful headlines, their own fortunes still feel pretty good. Home prices are holding steady in most regions. In Manhattan, “there’s a happening in the $4 million to $10 million range, predominantly fed by Wall Street bonuses,Barbara Corcoran. In San Francisco, prices are still rising even as frenzied overbidding quiets. “Inst-estate broker. And20 to 30 offers, now maybe you only get two or three,” says John Tealdi, a Bay Area realmost folks still feel pretty comfortable about their ability to find and keep a job.Many folks see silver linings to this slowdown. Potential home buyers would cheer for lower interestrates. Employers wouldn’t mind a little fewer bubbles in the job market. Many consumers seem to have beeinfluenced by stock-market swings, which investors now view as a necessary ingredient to a sustained boom. Diners might see an upside, too. Getting a table at Manhattan’s hot new Alain Ducasse restaur impossible. Not anymore. For that, Greenspan & Co. may still be worth toasting.-2, Paragraph 1), the author means ________.51. By “Ellen Spero isn’t biting her nails just yet” (Lines 1[A] Spero can hardly maintain her business[B] Spero is too much engaged in her work[C] Spero has grown out of her bad habit[D] Spero is not in a desperate situation52. How do the public feel about the current economic situation?[A] Optimistic.[B] Confused.[C] Carefree.[D] Panicked.-4, Paragraph 3) the author is talking53. When mentioning “the $4 million to $10 million range” (Lines 3about ________.[A] gold market[B] real estate[C] stock exchange[D] venture investment54. Why can many people see “silver linings” to the economic slowdown?[A] They would benefit in certain ways.[B] The stock market shows signs of recovery.[C] Such a slowdown usually precedes a boom.[D] The purchasing power would be enhanced.55. To which of the following is the author likely to agree?[A] A new boom, on the horizon.[B] Tighten the belt, the single remedy.[C] Caution all right, panic not.[D] The more ventures, the more chances.Text 4Americans today don’t place a very high value on intellect. Our heroes are athletes, entertainers, and entrepreneurs, not scholars. Even our schools are where we send our children to get a practical education --not to pursue knowledge for the sake of knowledge. Symptoms of pervasive anti-intellectualism in our schools aren’t difficult to find.says “Schools have always been in a society where practical is more important than intellectual,”　Left Back: A education writer Diane Ravitch. “Schools could be a counterbalance.” Ravitch’s latest boo Century of Failed School Reforms, traces the roots of anti-intellectualism in our schools, concluding they are anything but a counterbalance to the American distaste for intellectual pursuits.But they could and should be. Encouraging kids to reject the life of the mind leaves them vulnerable to exploitation and control. Without the ability to think critically, to defend their ideas and understand the ideasof others, they cannot fully participate in our democracy. Continuing along this path, says writer Earl Shorris, “We will become a second-rate country. We will have a less civil society.”“Intellect is resented as a form of power or privilege,” writes historian and professor Ric in Anti-Intellectualism in American Life, a Pulitzer-Prize winning book on the roots of anti-intellectualism inUS politics, religion, and education. From the beginning of our history, says Hofstadter, our democratic and populist urges have driven us to reject anything that smells of elitism. Practicality, common sense, and native intelligence have been considered more noble qualities than anything you could learn from a book.Ralph Waldo Emerson and other Transcendentalist philosophers thought schooling and rigorous book learning put unnatural restraints on children: “We are shut up in schools and college recitation roMark Twain’sor 15 years and come out at last with a bellyful of words and do not know a thing.”　Huckleberry Finn exemplified American anti-intellectualism. Its hero avoids being civilized -- going to school and learning to read -- so he can preserve his innate goodness.Intellect, according to Hofstadter, is different from native intelligence, a quality we reluctantly admire. Intellect is the critical, creative, and contemplative side of the mind. Intelligence seeks to grasp, manipulate,re-order, and adjust, while intellect examines, ponders, wonders, theorizes, criticizes and imagines.School remains a place where intellect is mistrusted. Hofstadter says our country’s e is in the grips of people who “joyfully and militantly proclaim their hostility to intellect and their eagerne to identify with children who show the least intellectual promise.”56. What do American parents expect their children to acquire in school?[A] The habit of thinking independently.[B] Profound knowledge of the world.[C] Practical abilities for future career.[D] The confidence in intellectual pursuits.57. We can learn from the text that Americans have a history of ________.[A] undervaluing intellect[B] favoring intellectualism[C] supporting school reform[D] suppressing native intelligence58. The views of Ravitch and Emerson on schooling are ________.[A] identical[B] similar[C] complementary[D] opposite59. Emerson, according to the text, is probably ________.[A] a pioneer of education reform[B] an opponent of intellectualism[C] a scholar in favor of intellect[D] an advocate of regular schooling60. What does the author think of intellect?[A] It is second to intelligence.[B] It evolves from common sense.[C] It is to be pursued.[D] It underlies power.Part BDirections:Read the following text carefully and then translate the underlined segments into Chinese. Your translation should be written clearly on ANSWER SHEET 2. (10 points)The relation of language and mind has interested philosophers for many centuries. 61) The Greeks assumed that the structure of language had some connection with the process of thought, which took root in Europe long before people realized how diverse languages could be.Only recently did linguists begin the serious study of languages that were very different from their own.Two anthropologist-linguists, Franz Boas and Edward Sapir, were pioneers in describing many native languages of North and South America during the first half of the twentieth century. 62) We are obliged tothem because s ome of these languages have since vanished, as the peoples who spoke them died out or became assimilated and lost their native languages. Other linguists in the earlier part of this century, however,nguage, were not always so grateful. 63) Thewho were less eager to deal with bizarre data from “exotic” lanewly described languages were often so strikingly different from the well studied languages of Europe and Southeast Asia that some scholars even accused Boas and Sapir of fabricating their data. Native Americanlanguages are indeed different, so much so in fact that Navajo could be used by the US military as a code during World War II to send secret messages.pupil, Benjamin Lee Whorf, continued the study of American Indian languages. 64) Being Sapir’sinterested in the relationship of language and thought, Whorf developed the idea that the structure of language determines the structure of habitual thought in a society. He reasoned that because it is easier to formulate certain concepts and not others in a given language, the speakers of that language think along one track and not along another. 65) Whorf came to believe in a sort of linguistic determinism which, in its strongest form, states that language imprisons the mind, and that the grammatical patterns in a language can produce far-reaching consequences for the culture of a society. Later, this idea became to be known as the Sapir-Whorf hypothesis, but this term is somewhat inappropriate. Although both Sapir and Whorf emphasized the diversity of languages, Sapir himself never explicitly supported the notion of linguistic determinism.2004年考研英语真题答案Section II: Use of English (10 points)21. [C] 22. [D] 23. [A] 24. [D] 25. [A]26. [B] 27. [C] 28. [D] 29. [A] 30. [B]31. [A] 32. [C] 33. [D] 34. [B] 35. [A]36. [B] 37. [B] 38. [D] 39. [A] 40. [C]Section III: Reading Comprehension (50 points)Part A (40 points)41. [C] 42. [A] 43. [D] 44. [B] 45. [C]46. [A] 47. [D] 48. [C] 49. [B] 50. [D]51. [D] 52. [A] 53. [B] 54. [A] 55. [C]56. [C] 57. [A] 58. [D] 59. [B] 60. [C]Part B (10 points)61. 希腊人认为, 语言结构与思维过程之间存在着某种联系。

江苏大学2004年硕士研究生入学考试试题答案

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2004年硕士研究生入学考试试卷(A卷)基础英语

北京第二外国语学院2004 年硕士研究生入学考试试卷〔A 卷〕考试科目：根底英语总分值：150 分考试说明：请将答案写在答题卷上将代表正确答案的字母涂黑I.GRAMMAR (20 points, 1 point each)1.As far as we know, in this matter Jim seems .A.to be in no way to blameB.to in no wav be to be blamedC.to be to blame in no wayD.to be blamed in no way2., he might have retired before the end.A.Didn’t he enjoy the concertB.Has he not enjoyed the concertC.Were he not enjoy the concertD.Had he not enjoyed the concert3.I don’t see how you can stop your daughter , she is lawfully old enough to get married.A.onceB. thusC. yetD. since4.A long line of traffic at the level crossing until the train had passed.A.would have waitedB. had to waitC. must have waitedD. should have waitedthe 5.The developing countries are the richly mineralized districts in the worlddeveloped countries are the districts which are short of minerals.A.anywayB. neverthelessC. whileD. instead6.Jane rented novels from the circulating library yesterday afternoon.A.two interesting AmericanB. two American interestingC. interesting two AmericanD. American two interesting7.The manager his suitcase in which there is plenty of cash yet, for he is not sure where he left it behind.A.had not foundB. has not foundC. did not findD. cannot find8.The minister didn’t show any interest in the democratic reforms .A.all in allB. after allC. not at allD. at all9.I regret a present to my friend when he got married last month.A.to have not madeB. not makingC. not having madeD. having not made10.I haven’t seen her .A.since longB. long sinceC. long agoD. long before11.Why this way? to meet him?A.are you walking / Do you wantB.do you walk / Do you wantC.do you walk / Are you wantingD.are you walking / Did you want12.Art critics insisted he an illustrator rather than an mist.A.beB. would beC. should beD. was13.“Did the audience participate in the play?〞“Yes, those actors to involve the audience.〞A.whom it was the functionB. of whom the function wasC. whose function it wasD. whose were the function14.“Will a bus stop here soon?〞“No,〞A.ten minutes ago one just went byB. one just went by ten minutes agoC. ten minutes ago just one went byD. just one went by ten minutes ago15.It was cold winter night.A.the/The/theB. a / The / theC. a/The / aD. a / A / the16.The man under a big tree over there isA.no other butB. none other thanC. none other butD. no one than17.He did not turn up. No moreA.did his brotherB. his brother didC. did not his brotherD. his brother did too18.A.could loseB. would have lostC. might loseD. ought to have lost19.The lady over there isA.Jane and Mary motherB. Jane and Mary’s motherC. Jane’s and Mary’s motherD. Jane’s and Mary mother20.Not even a word concerning these important matters.A.he mentionedB. he mentionsC. did he mentionD. he does mentionII.VOCABULARY (30 points, 1 point each)Section ADirections: In this section, there are ten sentences each with one word or phrase underlined Choose one of the four choices marked A, B, C, and D that best keeps the meaning ofthe sentence. Then mark the corresponding letter on the ANSWER SHEET byblackening it.1.Intermittent showers were forecast for the day.A.HeavyB. RecurrentC. All-dayD. Instantaneous2.The saucy child protruded his tongue.A.propelledB. showedC. projectedD. hurt3.A.extemporaneousB. well-preparedC. eloquentD. carefully-designed4.His loud voice drowned what the girl was trying to tell us.A.undulatedB. surprisedC. inundatedD. overturned5.We adorned our room with new rugs, lamps and pictures.A.embroideredB. embellishedC. furnishedD. addressed6.I am glad to hear about the young man’s good convalescence.A.personalityB. responseC. temperD. recovery7.When the woman assembles and brings all these books, she musters them.A.bartersB. takesC. gathersD. counts8.It is now generally assumed that the planets were formed by the accretion of gas and dust in a cosmic cloud.A.separationB. motionC. progressionD. accumulation9.Ghost stories are vestiges of a widespread belief in ghosts.A.legendsB. remnantsC. residencesD. reflections10.The process of respiration consists of two independent actions, inhaling and exhaling.A.speakingB. marketingC. expandingD. breathingSection B11.There was a nobility, about this simple-minded person w hich was .A.most engagedB. to be most engagingC. the most engagingD. most engaging12.The writer was not used to speaking in public, but when the opportunity presented itself, herose to the .A.chanceB. eventC. occasionD. circumstance13.Most of the author’s earlier works were published under aA.pseudonymB. misnomerC. nicknameD. namesake14.The black boys and girls need not have felt for their dark skin in the summer camp.A.self-effacingB. self-consciousC. self-centeredD. self-evident15.If you keep on working too hard, your health will .A.degenerateB. degradeC. deteriorateD. deform16.Several of the advertising hoardings had been by anti-racist slogans.A.deletedB. erasedC. mutilatedD. defaced17.Before the conference begins, let’s take an of the present situation.A.overviewB. overallC. overtureD. oversight18.The dreadful scenes of the major skirmish the children off their dinner.A.tookB. putC. sentD. set19.The purpose of the survey was to the parents with the changes television has made infamily life.A.notifyB. tellC. acquaintD. inform20.They had not cleaned the house for weeks and the health inspector found them living in theutmost .A.contaminationB. pollutionC. decayD. squalor21.We must bring him to our point of view on that subject.A.outB. forwardC. aroundD. about22.The students wondered why the instructor in the middle of his speech.A.broke awayB. broke inC. broke offD. broke out23.The U.N Security Council makes an attempt to adjust the between Israeland Palestine.A.problemB. disputeC. questionD. matter24.While typing, Helen has a habit of stopping to give her long and flowing hair asmooth.A.occasionallyB. simultaneouslyC. eventuallyD. promptly25.The old lady can’t hope to her cold in a few days.A.hold backB. get offC. get overD. hole up26.The island where these rare birds nest has been declared a area.A.observationB. reservationC. preservationD. conservation27.I just managed to a quick breath before I was sucked under the water by thepassing boat.A.snatchB. scratchthem theC. scrapeD. stretch28.A.vibratingB. wavingC. fluctuatingD. swings29.My house is the only brick one on the street. It and you can’t miss it.A.stands upB. sticks outC. looks outD. make out30.Some teenagers harbor a generalized resentment against society, whichrights and privileges of adults, although physically they are mature.A.deprivesB. restrictsB.rejects D. deniesIII.CLOZE (30points, 1 point each)PASSAGE 11. A. unattended B. unguarded C. unhindered D. unopposed2. A. period B. shift C. time D. hour3. A. may B. should C. would D. can’t4. A. truly B. sincerely C. purely D. fully5. A. uttering B. informing C. speaking D. announcing6. A. pretend B. lie C. convince D. cheat7. A. duty B. loyalty C. respect D. faith8. A. viewed B. observed C. regarded D. considered9. A. large B. expensive C. high D. strong10. A. make B. put C. get D. havePASSAGE 2Macaulay had wealth and fame, rank and power, and yet he tells us in his biography that he owed the happiest hours of his life (23) books. In a charming letter to a little girl, he says: “Thank you for your very pretty, letter. I am always glad to make my little girl happy, and nothing pleases me so much (24) to see that she likes books, for when she is as old as I am. she will find that they are better than all the candies and cakes, toys and plays, and sights in the world. If anyone would make me the greatest king that ever lived on (25) that I should not read books, I (26) not be a king. I would (27) be a poor man in a garret with plenty of books than a king who did not love (28) .〞Books, indeed, endow us (29) a whole enchanted palace of thoughts. In one way they give us an even more vivid idea than the actual (30) , just as reflections are often more beautiful than real nature.IV.READING COMPREHENSION (30 points, 3 points each)PASSAGE 1As long as this eclectic strategy serves the instructional purpose well, and as long as the teacher has the ability to explain to the students how they can succeed under various teaching styles, the use of various styles can be advantageous. However, if the use of various styles is merely trying technique after technique with no knowledge of how these techniques relate to teaching philosophies, the result could be said to be a state of unhealthy eclecticism, which shouldbe avoided.Various state teacher certification programs include a course in the academic study of educational philosophy. When the prospective teachers enrolled in such courses have previously assessed behavioral emphases and preferences underlying a philosophical position, such courses are infinitely more valuable. While condensed explanations of teaching styles/philosophies run the inherent risks of oversimplification and of being too judgmental, our purpose is to provide prospective teachers with a working framework to help them avoid the meaningless stereotypes associated with various educational philosophies.Effective teaching is not a matter of authoritarian versus non-authoritarian methodologies, older versus newer theories, or controlled classrooms versus non-controlled classrooms. Rather, responsible use of any teaching style/philosophy yields benefits for learners, whereas irresponsible use of any teaching style/philosophy yields the reverse.Classroom teachers do borrow from different philosophical systems, primarily as a means to assure variety in methods of instruction. However. a philosophical position is actually indicated by emphases and preferences that translate themselves into behavior. Thus it is the behavioral emphasis or preferences that should be identified to reveal the underlying set of philosophical assumptions.1.A prospective teacher should have his own personal philosophy of e ducation because .A.a preferred teaching philosophy is necessaryB.his preferred teaching style is the most effective oneC.he should develop his own teaching styleD.his personal belief system determines his instructional practice2.According to the author, which of the following approaches is encouraged in a teacher-training program?A.To introduce various teaching theories and try them out in class.B.To help teachers master various teaching methodologies.C.To help teachers understand the real significance behind each teaching theory.D.A.newer teaching theoriesB.teacher’s responsibility in using any teaching philosophyC.non-controlled classroomsD.non-authoritarian methodologyPASSAGE 2There are several ways to think of politeness. These might involve ideas like being tactful, modest and nice to other people. In the study of linguistic politeness, the most relevant concept is ‘face’. Your face, in pragmatics, is your public self-image. This is the emotional and social sense of self that every person has and expects everyone else to recognize.Politeness is showing awareness of another person’s face. If you say someth ing that represents a threat to another person’s self-image, that is called a face-threatening act. For example, if you use a direct speech act to order someone to do something (Give me that paper!), you are acting as if you have more social power than the other person. If you do not actually have that social power, then you are performing a face-threatening act. An indirect speech act. in the form ofa question (Could you pass me that paper, please?), removes the assumption of social power. You appear to be asking about ability. This makes your request less threatening to the other person’s sense of self. Whenever you say something that lessens the possible threat to another’s face. It’s called a face-saving act.4.Which of the following is NOT an example of face-threatening act?A.You sit there.B.Why don’t you sit there?C.Would you sit there?D.You’re asked to sit there.5.Which of the following shows concern for a person’s negative face?A.I’m afraid you’re late.B.You’re late.C.You know you’re late.D.I sorry, to say you’re late.6.As is discussed in the passage, Pragmatics mainly studies .A.a speaker’s face-saving actB.a speaker’s positive face or negative faceC.what the speaker sayD.a speaker’s implied intentionsPASSAGE 3broadcast network had been sold, two networks were sold that year - ABC and NEC.The issue of media ownership is important. If only a few corporations direct the media industries in this country, the outlets for differing political viewpoints and innovative ideas could be limited.7.Which of the following is tree of the media?A.They used to sell and buy each other in great numbers.B.They are trading each other in greater numbers today.C.They used to be controlled by two networks - ABC and NBC.D.They have stopped the trend of acquisitions in the 1990s.8.According to the passage, what makes acquisitions easier?A.The changing technology employed by the media.B.The media’s increasing profits in the marketplace.C.The ever tougher regulations of the FCC on the media since 1980.D.The availability of the media’s stocks on stock exchanges.9.What is the FCC’s new policy regarding media alliances?A.B.C.D.10.The issue of media ownership is important because .A.it affects the amount of money the stockholders will makeB.it decides whether we can have different aspects of the mediaC.it concerns the channels through which to express opinionsD.it means that more and more people will hold onto only a few stationsV.PARAPHRASING (20 points, 4 points each)Explain the five underlined sentences in your own words, and give examples to illustrate your explanation if necessary. Write your answers on THE ANSWER SHEET.Culture, in anthropology, the patterns of behavior and thinking that people living in social groups learn, create, and share. (1) Culture distinguishes one human group from others. It alsodistinguishes humans from other animals. A people’s culture includes their beliefs, rules of behavior, language, rituals, art, technology, styles of dress, ways of producing and cooking food, religion, and political and economic systems.VI.WRITING (20 points)In today’s increasingly technological society, many students think that college courses in the liberal arts (art, music, philosophy, literature) should be cancelled, because they do not contribute much to their career preparation.Do you agree or disagree with the above statement?A 卷答案局部Ⅰ. Grammar (20 points, 1 point each)1. A2. D3. D4. B5. C6. A7. B8. D9. C 10. B11. A 12. D 13. C 14. B 15. D16. B 17. A 18. B 19. B 20. CⅡ. Vocabulary (30 points, 1 point each )1. B2. C3. A4. C5. B6. D7. C8. D9. B 10. D11. D 12. C 13. A 14. B 15. C16. D 17. A 18. B 19. C 20. D21. C 22. A 23. B 24. A 25. C26. D 27. A 28. C 29. B 30. DⅢ. Cloze (30 points, 1 point each blank)1. C2. D3. B4. A5. D6. C7. B8. D9. C 10. A11.what 21. may12.made 22. without13.in 23. to14.and 24. as15.into 25. earth16.fill 26. would17.out 27. rather18.who 28. reading/books19.other 29. with20.vivid 30. reality/world1.D2. C3. B4. C5.A6. D7. B8. D9. C 10. CⅤ. Paraphrasing (20 points, 4 points each sentence)1.2.Therefore, the terms culture and society can in a way be used instead of each other.3.4.A symbol might be related to the object, idea, feeling, or behavior it speaks about in an indirect way or they may have no relation at all.5.Ⅵ. Writing (20 points)The Importance of Liberal Arts for College Students Some college students believe that in an increasingly technological society courses in the liberal arts should be eliminated for they do not contribute much to their career preparation. I donot agree with them because I think knowledge gained from courses in liberal arts provides individuals with necessary guidelines and motivation for successful careers, well-developed personalities and happy lives.In sum, all the courses of liberal arts should be preserved and promoted for they are indispensable for individual progress, success and happiness.。

2004年研究生入学考试英语试题

Section Ⅰ Listening Comprehension Part A(每题1分，共20分)Directions: This section is designed to test your ability to understand spoken English. You will hear a selection of recorded materials and you must answer the questions that accompany them. There are three parts in this section, Part A, Part B, and Part C. Remember, you should first put down your answers in your test booklet. At the end of the listening comprehension section, you will have five minutes to transfer all your answers from your test booklet to ANSWER SHEET I. Now look at Part A in your test booklet. Part A Directions: For Quesstions1-5,you will hear a talk about Boston Museum of Fine Art. While you listen, fill out the table with the information you have heard. Some of the information has been given to you in the table. Write only 1 word or number in each numbered box. You will hear the recording twice. You now have 25 seconds to read the table below.(5 points) 1、Geography of BelgiumThree main regions coastal plaincentral plateau Highest 1 （本题分值：1分）【正确答案】 highlands 2、altitude of the coastal plain 2 m （本题分值：1分）【正确答案】 20 3、Climate near the sea 3 humid （本题分值：1分）【正确答案】 mild 4、Particularly rainy months of the years 4 April （本题分值：1分）【正确答案】 November 5、Average temperatures in July in Brussels low 13℃ high 5 ℃ （本题分值：1分）【正确答案】 22 Section Ⅰ Part B(每题1分，共5分)Directions: For Questions 6-10,you will hear an interview with Mr. Saffo from the Institute for the Future. While you listen, complete the sentences or answer the questions. Use not more than 3 words for each answer. You will hear the recording twice. You now have 25 seconds to read the sentences and questions below. ( 5 points ) 6、What is Saffo according to himself? （本题分值：1分）【正确答案】 A (technology)forecaster 7、The Institute for the Future provides services to private companies and （本题分值：1分）【正确答案】 government agencies 8、The Institute believes that to think systematically about the long-range future is （本题分值：1分）【正确答案】 (a)meaningful(exercise) 9、To succeed in anything, one should be flexible, curious and （本题分值：1分）【正确答案】 open to change 10、What does Saffo consider to be essential to the work of a team? （本题分值：1分） Section Ⅰ Part C（共三节，满分10分） Directions: You will hear three pieces of recorded material. Before listening to each one, you will have time to read the questions related to it. While listening, answer each question by choosing A,B,C or D . After listening, you will have time to check your answers. You will hear each piece once only. ( 10 points ) Questions 11-13 are based on the following talk about naming newborns. You now have 15 seconds to read questions 11-13. 11、What do we often do with the things we love? （本题分值：1分）【正确答案】 D A.Ask for their names. babies after them. C.Put down their names. D.Choose names for them. 12、 The unpleasant meaning of an old family name is often overlooked if （本题分值：1分）【正确答案】 B A. the family tree is fairly limited. B. the family tie is strong enough. C.the name is commonly used. D.nobody in the family complains. 13、 Several months after a baby's birth, its name will （本题分值：1分）【正确答案】 C A.show the beauty of its own. B.develop more associations. C.lose the original meaning. D.help form the baby's personality. Questions 14-16 are based on the biography of Bobby Moore, an English soccer player. You now have 15 seconds to read Questions 14-16. 14. How many matches did Moore play during his professional career? （本题分值：1分）【正确答案】 D A. 90. B .108. C.180. D. 668. 15、In 1964, Bobby Moore was made （本题分值：1分）【正确答案】 A A.England's footballer of the year. B.a soccer coach in West Germany. C.a medalist for his sportsmanship. D.a number of the Order of the British Empire. 16、After Moore retired from playing, the first thing he did was （本题分值：1分）【正确答案】 C A.editing Sunday Sport. B.working for Capital Radio. C.managing professional soccer teams. D.developing a sports marketing company. Questions 17-20 are based on the on the city of Belfast. You now have 20 seconds to read Questions 17-20. 17. Belfast has long been famous for its （本题分值：1分）【正确答案】 B A. oil refinery. B. linen textiles. C.food products. D. deepwater port. 18、Which of the following does Belfast chiefly export? （本题分值：1分）【正确答案】 A A. Soap. B. Grain. C.Steel. D.Tobacco. 19、When was Belfast founded? （本题分值：1分）【正确答案】 A A. In 1177. B. In 1315. C.In the 16th century. D. In the 17th century. 20、 What happened in Belfast in the late 18th century? （本题分值：1分）【正确答案】 C A. French refugees arrived. B. The harbor was destroyed. C.Shipbuilding began to flourish. D.The city was taken by the English. Section II Use of English（满分10分） Directions: Read the following text. Choose the best word(s) for each numbered blank and mark A,B,C or D on ANSWER SHEET 1. (10 points) Many theories concerning the causes of juvenile delinquency (crimes committed by young people) focus either on the individual or on society as the major contributing influence. Theories (21)[] on the individual suggest that children engage in criminal behavior (22)[] they were not sufficiently penalized for previous misdeeds or that they have learned criminal behavior through (23)[] with others. Theories focusing on the role of society that children commit crimes in (24)[] to their failure to rise above their socioeconomic status (25)[] as a rejection of middle-class values. Most theories of juvenile delinquency have focused on children from disadvantaged families, (26)[] the fact that children from wealthy homes also commit crimes. The latter may commit crimes (27)[] lack of adequate parental control. All theories, however, are tentative and are (28)[] to criticism. Changes in the social structure may indirectly (29)[] juvenile crime rates. For example, changes in the economy that (30) [] to fewer job opportunities for youth and rising unemployment (31)[] make gainful employment increasingly difficult to obtain. The resulting discontent may in (32)[] lead more youths into criminal behavior. Families have also(33)[] changes these years. More families consist of one parent households or two working parents;(34)[], children are likely to have less supervision at home (35)[] was common in the traditional family (36)[]. This lack of parental supervision is thought to be an influence on juvenile crime rates. Other (37)[] causes of offensive acts include frustration or failure in school, the increased (38)[] of drugs and alcohol, and the growing (39)[] of child abuse and child neglect. All these conditions tend to increase the probability of a child committing a criminal act, (40)[] a direct causal relationship has not yet been established. 21、（本题分值：0.5分）【正确答案】 C ［注释］"很多有关少年犯罪原因的理论，要么把个⼈当成主要的影响因素，要么把社会当成主要的影响因素。

2004年硕士入学考题-会计学

2004年硕士入学考题-会计学（a卷）专业：会计学考试科目：会计学、财务会计、财务管理、审计学重要提示：考生须将所有答案写在答题纸上，本试题上的任何标记不作判卷依据会计学部分（30分）一、名词解释(每题3分，共12分)1、复式记账凭证2、平行登记3、永续盘存制4、静态报表二、论述题（每题9分，共18分）1、试述会计对象的内容.2、什么是借贷记账法试算平衡?有哪几种计算方法?财务会计部分（40分）一、名词解释（每题3分，共9分）1．成本法 2．存货 3．无形资产二、论述题（共21分）1．利润表的性质和作用？（10分）2．为什么要将负债分为流动负债和长期负债？（11分）三、业务题（共10分）1．设某公司98年11月份有关存货资料如下：单位数量单位成本（元）月初结存 1000 511月2日购进 9000 5.411月5日销售（单位售价6.5） 350011月14日购进 4000 5.511月16日销售（单位售价6.3） 800011月29日购进 2000 6.04要求：分别采用定期盘存制的后进先出法、先进先出法计算该月的销售成本和期末存货结存成本。

财务管理部分（40分）一、名词解释（每题3分，共9分）1．风险报酬 2．现金流量 3．混合性融资二、简答题（每题8分，共16分）1．简述企业财务管理目标以及影响企业财务目标实现的因素。

2．为什么许多大公司愿意采用低正常股利加超额股利政策？三、计算、分析题（共15分）某公司有两个互相排斥的投资项目，项目a的投资额为150000元，寿命期为5年，5年中每年营业现金流量为58000元；项目b的投资额为200000元，寿命期为8年，8年中每年营业现金流量为55000元。

假设资本成本为15%。

该公司应如何进行决策。

（要求：计算a、b项目的净现值及年均净现值）fvifa15%，5 = 3.3522fvifa15%，8 = 4.4873审计学部分（40分）一、名词解释（每题3分，共12分）1、审计证据2、符合性测试3、审计报告4、内部审计二、论述题（每题14分，共28分）1、注册会计师对被审单位的会计报表认为存在哪些情况之一时，应当出具否定意见审计报告？应怎样表述？组成注册会计师职业道德规范有哪几个层次？试扼要地加以叙述。

2004年全国硕士研究生入学统一考试数学一真题及答案

2004年全国硕士研究生入学统一考试数学一试题答案一、填空题（本题共6小题，每小题4分，满分24分．把答案填在题中横线上．）（1）曲线ln y x =上与直线1x y +=垂直的切线方程为．【答案】1y x =- 【考点】导数的几何意义【难易度】★ 【详解】解析：由11)(ln =='='xx y ，得1x =, 可见切点为)0,1(，于是所求的切线方程为 )1(10-⋅=-x y ，即 1-=x y .（2）已知()x x f e xe -'=，且(1)0f =，则()f x = ．【答案】21ln 2x 【考点】不定积分的换元法【难易度】★★ 【详解】解析：令t e x=，则t x ln =，于是有t t t f ln )(='，即 .ln )(xxx f =' 积分得2ln 1()ln (ln )ln 2x f x dx xd x x C x ===+⎰⎰. 利用初始条件(1)0f =, 得0C =，故所求函数为()f x = 21ln 2x .（3）设L 为正向圆周222x y +=在第一象限中的部分，则曲线积分x y y x Ld 2d -⎰的值为．【答案】π23 【考点】第二类曲线积分的计算；格林公式【难易度】★★★ 【详解】解析：正向圆周222=+y x 在第一象限中的部分，可表示为.20:,sin 2,cos 2πθθθ→⎩⎨⎧==y x于是θθθθθπd ydx xdy L]sin 2sin 22cos 2cos 2[220⋅+⋅=-⎰⎰=.23sin 2202πθθππ=+⎰d （4）欧拉方程)0(02d d 4d d 222>=++x y xyx x y x 的通解为．【答案】221x C x C y+=，其中12,C C 为任意常数【考点】欧拉方程【难易度】★★ 【详解】解析：令te x =，则dtdy x dt dy e dx dt dt dy dx dy t 1==⋅=-，][11122222222dtdy dt y d x dx dt dt y d x dt dy x dx y d -=⋅+-=，代入原方程，整理得02322=++y dt dydty d ，解此方程，得通解为 .221221xc x c e c ec y t t+=+=-- （5）设矩阵210120001A ⎡⎤⎢⎥=⎢⎥⎢⎥⎣⎦，矩阵B 满足**2ABA BA E ＝＋，其中*A 为A 的伴随矩阵，E 是单位矩阵，则B = ．【答案】19【考点】抽象型行列式的计算；伴随矩阵【难易度】★★ 【详解】解析：方法1：已知等式两边同时右乘A ，得A A BA A ABA +=**2，而3=A ，于是有A B AB +=63，即 A B E A =-)63(，再两边取行列式，有363==-A B E A ，而 2763=-E A ，故所求行列式为.91=B 方法2：由题设条件**2ABA BA E =+ 得 *(2)A E B A E-=两边取行列式，得*21A E B A E -==其中 2101203001A ==， 312A A A -*===9 0102100001A E -==1故1192B A E A*==- （6）设随机变量X 服从参数为λ的指数分布，则{}P X DX >= ．【答案】e1【考点】指数分布【难易度】★★ 【详解】解析：由题设，知21λ=DX ，于是}{DX X P >=dx e X P x ⎰+∞-=>λλλλ1}1{=.11ee x=-∞+-λλ 二、选择题（本题共8小题，每小题4分，满分32分．在每小题给出的四个选项中，只有一项是符合题目要求的，把所选项前的字母填在题后的括号内．）（7）把0x +→时的无穷小量t t t t t t xxx d sin ,d tan ,d cos 3022⎰⎰⎰===γβα排列起来，使排在后面的是前一个的高阶无穷小，则正确的排列次序是（）（A ）,,αβγ （B ）,,αγβ （C ）,,βαγ （D ）,,βγα 【答案】（B ）【考点】无穷小量的比较【难易度】★★ 【详解】解析：方法1：0cos 2tan lim cos tan limlim 22002=⋅==+++→→→⎰⎰xxx dtt dt t x xx x x αβ，可排除(C),(D)选项，又 xx x x dtt dtt x xxx x tan 221sin lim tan sin limlim 2300302⋅==+++→→→⎰⎰βγ=∞=+→20lim 41x x x ，可见γ是比β低阶的无穷小量，故应选(B). 方法2：221000cos cos lim limlim ,x kkk x x x t dt t x x kxα+++-→→→=⎰洛欲使上式极限存在但不为0，应取1k =，0lim 1x xα+→=，所以（当+→0x 时）α与x 同阶.2120000tan tan 22tan lim limlim lim ,x kkk k x x x x tdt x x xx x kx kx β++++--→→→→⋅==⎰洛欲使上式极限存在但不为0，应取3k =,有302lim 3x x β+→=，所以（当+→0x 时）β与3x 同阶. 31322120000sin sin lim lim lim lim ,22xk k k k x x x x t dtx x xx x kx kx γ++++---→→→→==⎰洛欲使上式极限存在但不为0，应取2k =,有201lim 4x x γ+→=，所以（当+→0x 时）γ与2x 同阶.因此，后面一个是前面一个的高阶小的次序是,,αγβ，选（B ）.（8）设函数()f x 连续，且(0)0f '>，则存在0δ>，使得（）（A ）()f x 在(0,)δ内单调增加．（B ）()f x 在(,0)δ-内单调减少．（C ）对任意的(0,)x δ∈有()(0)f x f >．（D ）对任意的(,0)x δ∈-有()(0)f x f >．【答案】（C ）【考点】函数极限的局部保号性；导数的概念【难易度】★★ 【详解】解析：由导数的定义，知,0)0()(lim)0(0>-='→xf x f f x根据极限的保号性，知存在0>δ，当),0()0,(δδ -∈x 时，有0)0()(>-xf x f即当)0,(δ-∈x 时，()(0)f x f <; 而当),0(δ∈x 时，有()(0)f x f >. 故应选(C).（9）设n n a∑∞=1为正项级数，下列结论中正确的是（）（A ）若0lim =∞→n n na ，则级数n n a∑∞=1收敛．（B ）若存在非零常数λ ，使得λna nn =∞→lim ，则级数n n a ∑∞=1发散．（C ）若级数n n a∑∞=1收敛，则0lim 2=∞→n n a n ．（D ）若级数n n a∑∞=1发散，则存在非零常数λ ，使得λna n n =∞→lim ．【答案】（B ）【考点】比较审敛法的极限形式【难易度】★★ 【详解】解析：方法1：排斥法：取n n a n ln 1=，则n n na ∞→lim =0，但∑∑∞=∞==11ln 1n n n nn a 发散，排除(A)，(D)；又取nn a n 1=，则级数∑∞=1n na收敛，但∞=∞→n n a n 2lim ，排除(C), 故应选(B).方法2：证明(B)正确. lim n n na λ→∞=,即lim 1n n a nλ→∞=.因为11n n∞=∑发散，由比较判别法的极限形式知，1nn a∞=∑发散.（10）设()f x 为连续函数，1()d ()d t tyF t yf x x =⎰⎰,则(2)F '=（）（A ）2(2)f （B ）(2)f （C ）(2)f - （D ）0 【答案】（B ）【考点】积分上限的函数及其导数【难易度】★★★ 【详解】解析：方法1：交换积分次序，得⎰⎰=tt ydx x f dy t F 1)()(=⎰⎰⎰-=t x tdx x x f dx dy x f 111)1)((])([于是，)1)(()(-='t t f t F ，从而有 )2()2(f F ='，故应选(B). 方法2：设()()x f x Φ=111()()[()()]()(1)()t t t tyF t dy f x dx t y dy t t y dy ==Φ-Φ=Φ--Φ⎰⎰⎰⎰()()(1)()()()(1),F t t t t t f t t ''=Φ-+Φ-Φ=- (2)(2)F f '=，选(B).（11）设A 是3阶方阵，将A 的第1列与第2列交换得B ，再把B 的第2列加到第3列得C ，则满足AQ C =的可逆矩阵Q 为（）（A ）010100101⎡⎤⎢⎥⎢⎥⎢⎥⎣⎦．（B ）⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡100101010．（C ）⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡110001010．（D ）⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡100001110．【答案】（D ）【考点】矩阵的初等变换【难易度】★★ 【详解】解析：由题设，有B A =⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡100001010， 100010100011011100011100.001001001001B A A AQ ⎡⎤⎡⎤⎡⎤⎡⎤⎢⎥⎢⎥⎢⎥⎢⎥===⎢⎥⎢⎥⎢⎥⎢⎥⎢⎥⎢⎥⎢⎥⎢⎥⎣⎦⎣⎦⎣⎦⎣⎦故011100001Q ⎡⎤⎢⎥=⎢⎥⎢⎥⎣⎦，应选(D). （12）设A ，B 为满足0AB =的任意两个非零矩阵，则必有（）（A ） A 的列向量组线性相关，B 的行向量组线性相关．（B ） A 的列向量组线性相关，B 的列向量组线性相关．（C ） A 的行向量组线性相关，B 的行向量组线性相关．（D ） A 的行向量组线性相关，B 的列向量组线性相关．【答案】（A ）【考点】向量组线性相关的判别法【难易度】★★ 【详解】解析：方法1：设A 为n m ⨯矩阵，B 为s n ⨯矩阵，则由0AB =知，n B r A r <+)()(，其中n 是矩阵A 的列数，也是B 的行数又,A B 为非零矩阵，必有()0,()0r A r B >>. 可见(),()r A n r B n <<, 即A 的列向量组线性相关，B 的行向量组线性相关，故应选(A).方法2：由0AB =知，B 的每一列均为0Ax =的解，而B 为非零矩阵，即0Ax =存在非零解，可见A 的列向量组线性相关.同理，由0AB =知，O A B TT =，于是有T B 的列向量组线性相关，从而B 的行向量组线性相关，故应选(A).方法3：设 (),i j l m A a ⨯=()i j m n B b ⨯=, 记 ()12m A A A A =0AB =⇒()11121212221212n n m m m mn b b b b b b A A A bb b ⎛⎫⎪⎪⎪⋅⋅⋅ ⎪⎪⎝⎭()1111110mmn m n m b A b A b A b A =++++=（1）由于0B ≠, 所以至少有一 0i j b ≠(1,1i m j n ≤≤≤≤), 从而由（1）知, 112210j j i j i m m b A b A b A b A +++++= , 于是 12,,,m A A A 线性相关.又记 12m B B B B ⎛⎫⎪ ⎪= ⎪ ⎪ ⎪⎝⎭ ,则0AB =⇒11121121222212m m l l l m m a a a B a a a B a a a B ⎛⎫⎛⎫ ⎪ ⎪ ⎪ ⎪ ⎪ ⎪⋅⋅⋅ ⎪ ⎪ ⎪ ⎪⎝⎭⎝⎭ 1111221211222211220m m m m l l l m m a B a B a B a B a B a B a B a B a B +++⎛⎫⎪+++ ⎪== ⎪ ⎪ ⎪+++⎝⎭ 由于0A ≠,则至少存在一 0i j a ≠(1,1i l j m ≤≤≤≤),使 11220i i i j j im m a B a B a B a B ++++= , 从而 12,,,m B B B 线性相关,故应选（A ）.（13）设随机变量X 服从正态分布(0,1)N ，对给定的(01)αα<<，数u α满足{}P X u αα>=．若{}P X x α<= ，则x 等于（）（A ）2u α．（B ）21α-u．（C ）21αu -．（D ）u 1-α ．【答案】（C ）【考点】标准正态分布；分位数的概念【难易度】★★★ 【详解】解析：由标准正态分布概率密度函数的对称性知，αα=-<}{u X P ，于是}{2}{}{}{}{11x X P x X P x X P x X P x X P ≥=-≤+≥=≥=<-=-α即有21}{α-=≥x X P ，可见根据定义有21α-=u x ，故应选（C ）. （14）设随机变量12,,,(1)n X X X n > 独立同分布，且其方差为20σ>．令i ni X n Y ∑==11，则（）（A ）n Y X 21),(Cov σ=．（B ）21),(Cov σ=Y X ．（C ）212)(σn n Y X D +=+．（D ）211)(σnn Y X D +=-．【答案】（A ）【考点】随机变量的方差的性质；协方差的性质【难易度】★★ 【详解】解析：先计算1(,)Cov X Y ，因为11ni i Y X n ==∑，故1111112111(,)(,)(,)(,)n ni i i i Cov X Y Cov X X Cov X X Cov X X n n n ====+∑∑=.1121σnDX n = 三、解答题（本题共9小题，满分94分．解答应写出文字说明、证明过程或演算步骤．）（15）（本题满分12分）设2e a b e <<<，证明 )(e 4ln ln 222a b a b ->-．【考点】拉格朗日中值定理；函数单调性的判别【难易度】★★★ 【详解】解析：方法1：对函数x 2ln 在[,]a b 上应用拉格朗日中值定理，得.),(ln 2ln ln 22b a a b a b <<-=-ξξξ设t t t ln )(=ϕ，则2ln 1)(t tt -='ϕ，当t e >时， ,0)(<'t ϕ 所以)(t ϕ单调减少，从而)()(2e ϕξϕ>，即2222ln ln ee e =>ξξ，故 )(4ln ln 222a b e a b ->-. 方法2：设x e x x 224ln )(-=ϕ，则 24ln 2)(e x x x -='ϕ， 2ln 12)(xx x -=''ϕ, 所以当x e >时，,0)(<''x ϕ 故)(x ϕ'单调减少，从而当2e x e <<时， 044)()(222=-='>'e e e x ϕϕ，即当2e x e <<时，)(x ϕ单调增加.因此当2e x e <<时，)()(a b ϕϕ>，即 a ea b e b 22224ln 4ln ->-，故 )(4ln ln 222a b e a b ->-. 方法3：设2224()ln ln ()x x a x a e ϕ=---, 则 2ln 4()2x x x e ϕ'=-21l n ()2xx xϕ-''=,∴x e >时, ()0x ϕ''<()x ϕ'⇒ , 从而当2e x e <<时,22244()()0x e e eϕϕ''>=-=, 2e x e ⇒<<时, ()x ϕ单调增加.2e a b e ⇒<<<时, ()()0x a ϕϕ>=。

北京大学04年硕士研究生入学考试法学综合A及答案2004

北京大学2004年法学硕士试题和参考答案考试科目:法学综合A一,宪法1请简述我国公民的基本权利----平等权的基本内容.[参考答案] 公民在法律面前一律平等,是我国公民的一项基本权利,也是社会主义法制的一个基本原则.其内容是:第一,我国公民不分民族、种族、性别、职业、家庭出身、宗教信仰、教育程度、财产状况、居住期限，都一律平等地享有宪法和法律规定的权利，也平等地履行宪法和法律规定的义务。

第二，任何人的合法权益都一律平等地受到保护，对违法行为一律予以追究，决不允许任何违法犯罪分子逍遥法外。

第三，在法律面前，不允许任何公民享有法律以外的特权，任何人不得强迫任何公民承担法律以外的义务，不得使公民受到法律以外的惩罚。

就广义而言，我国公民的平等权还包括司法平等，即公民在适用法律上一律平等，又包括公民在守法上的平等。

与资本主义宪法中平等权不同，我国宪法的平等原则并不包括立法上的平等（个人认为：应该有相对的立法上的平等，不过这里不用深入讨论）。

因为我国是人民民主专政的国家，广大人民群众还需要对少数敌对分子实行阶级压迫，我国宪法中的平等原则就是肯定这种阶级秩序的基础上的平等。

[参考资料] 魏定仁主编：《宪法学》，北大出版社1994年版2，辨析：行宪政必有宪法，有宪法必有宪政。

[参考答案] 行宪政必有宪法，但有宪法未必有宪政。

宪政是宪法发展史上的一个重要概念，其主要内涵是指，依照宪法规定所产生的政治制度，使宪法规范与宪法实施的政治实践相结合的产物。

宪政是由意识形态和文化决定的一系列特殊道德的观点，如尊重人的尊严；宪法必须考虑到国家权力、公共政策和法律的“合法性”，以及人民对政府极其行为的“同意”。

第一，宪政必须是基于宪法。

作为宪法实践的基础，没有宪法的存在就谈不上宪政，也就是说，如果在一个国家中，不存在一个被称为宪法的根本法，或者是宪法的存在的权威被人们严重忽视，宪政是无从谈起的。

因此，要实现宪政，就必须要强化宪法作为根本法的权威，宪法是法，不是简单的政治纲领或者政策。

2004—数一真题标准答案及解析

2004年全国硕士研究生入学统一考试数学一真题一、填空题〔此题共6小题，每题4分，总分值24分. 把答案填在题中横线上〕〔1〕曲线y=lnx 上与直线1=+y x 垂直的切线方程为__________ . 〔2〕xxxee f -=')(，且f(1)=0, 那么f(x)=__________ .〔3〕设L 为正向圆周222=+y x 在第一象限中的局部，那么曲线积分⎰-Lydx xdy 2的值为__________.〔4〕欧拉方程)0(024222>=++x y dx dyx dxy d x 的通解为. __________ . 〔5〕设矩阵⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡=100021012A ，矩阵B 满足E BA ABA +=**2，其中*A 为A 的伴随矩阵，E 是单位矩阵，那么=B __________ .〔6〕设随机变量X 服从参数为λ的指数分布，那么}{DX X P >= __________ .二、选择题〔此题共8小题，每题4分，总分值32分. 每题给出的四个选项中，只有一项符合题目要求，把所选项前的字母填在题后的括号内〕〔7〕把+→0x 时的无穷小量dt t dt t dt t xx x⎰⎰⎰===302sin ,tan ,cos 2γβα，使排在后面的是前一个的高阶无穷小，那么正确的排列次序是(A) γβα,,. (B) βγα,,. (C) γαβ,,. (D) αγβ,,. [ ] 〔8〕设函数f(x)连续，且,0)0(>'f 那么存在0>δ，使得(A) f(x)在〔0，)δ内单调增加. 〔B 〕f(x)在)0,(δ-内单调减少. (C) 对任意的),0(δ∈x 有f(x)>f(0) .(D) 对任意的)0,(δ-∈x 有f(x)>f(0) . [ ]〔9〕设∑∞=1n na为正项级数，以下结论中正确的选项是(A) 假设n n na ∞→lim =0，那么级数∑∞=1n na收敛.〔B 〕假设存在非零常数λ，使得λ=∞→n n na lim ，那么级数∑∞=1n na发散.(C) 假设级数∑∞=1n na收敛，那么0lim 2=∞→n n a n .(D) 假设级数∑∞=1n na发散, 那么存在非零常数λ，使得λ=∞→n n na lim . [ ]〔10〕设f(x)为连续函数，⎰⎰=t tydx x f dy t F 1)()(，那么)2(F '等于(A) 2f(2). (B) f(2). (C) –f(2). (D) 0. [ ]〔11〕设A 是3阶方阵，将A 的第1列与第2列交换得B,再把B 的第2列加到第3列得C, 那么满足AQ=C 的可逆矩阵Q 为(A) ⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡101001010. (B) ⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡100101010. (C) ⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡110001010. (D) ⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡100001110. [ ]〔12〕设A,B 为满足AB=O 的任意两个非零矩阵，那么必有 (A) A 的列向量组线性相关，B 的行向量组线性相关. (B) A 的列向量组线性相关，B 的列向量组线性相关. (C) A 的行向量组线性相关，B 的行向量组线性相关.(D) A 的行向量组线性相关，B 的列向量组线性相关. [ ]〔13〕设随机变量X 服从正态分布N(0,1)，对给定的)10(<<αα，数αu 满足αα=>}{u X P ，假设α=<}{x X P ，那么x 等于(A) 2αu . (B) 21α-u. (C) 21α-u . (D) α-1u . [ ]〔14〕设随机变量)1(,,,21>n X X X n 独立同分布，且其方差为.02>σ 令∑==ni i X n Y 11，那么(A) Cov(.),21nY X σ= (B) 21),(σ=Y X Cov .(C) 212)(σn n Y X D +=+. (D) 211)(σnn Y X D +=-. [ ] 〔15〕〔此题总分值12分〕设2e b a e <<<, 证明)(4ln ln 222a b ea b ->-. 〔16〕〔此题总分值11分〕某种飞机在机场降落时，为了减少滑行距离，在触地的瞬间，飞机尾部张开减速伞，以增大阻力，使飞机迅速减速并停下.现有一质量为9000kg 的飞机，着陆时的水平速度为700km/h. 经测试，减速伞翻开后，飞机所受的总阻力与飞机的速度成正比〔比例系数为).100.66⨯=k 问从着陆点算起，飞机滑行的最长距离是多少？注kg 表示千克，km/h 表示千米/小时. 〔17〕〔此题总分值12分〕计算曲面积分其中∑是曲面)0(122≥--=z y x z 的上侧.〔18〕〔此题总分值11分〕设有方程01=-+nx x n，其中n 为正整数. 证明此方程存在惟一正实根n x ，并证明当1>α时，级数∑∞=1n n x α收敛.〔19〕〔此题总分值12分〕设z=z(x,y)是由0182106222=+--+-z yz y xy x 确定的函数，求),(y x z z =的极值点和极值. 〔20〕〔此题总分值9分〕设有齐次线性方程组试问a 取何值时，该方程组有非零解，并求出其通解.〔21〕〔此题总分值9分〕设矩阵⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡---=51341321a A 的特征方程有一个二重根，求a 的值，并讨论A 是否可相似对角化. (22)〔此题总分值9分〕设A,B 为随机事件，且21)(,31)(,41)(===B A P A B P A P ，令求：〔I 〕二维随机变量(X,Y)的概率分布；〔II 〕X 和Y 的相关系数.XY ρ〔23〕〔此题总分值9分〕设总体X 的分布函数为其中未知参数n X X X ,,,,121 >β为来自总体X 的简单随机样本，求：〔I 〕 β的矩估计量；〔II 〕 β的最大似然估计量.2004年数学一试题分析、详解和评注一、填空题〔此题共6小题，每题4分，总分值24分. 把答案填在题中横线上〕〔1〕曲线y=lnx 上与直线1=+y x 垂直的切线方程为1-=x y .【分析】此题为根底题型，相当于切线的斜率为1，由曲线y=lnx 的导数为1可确定切点的坐标. 【详解】由11)(ln =='='xx y ，得x=1, 可见切点为)0,1(，于是所求的切线方程为 )1(10-⋅=-x y ，即 1-=x y .【评注】此题也可先设切点为)ln ,(00x x ，曲线y=lnx 过此切点的导数为11=='=x y x x ，得10=x ，由此可知所求切线方程为)1(10-⋅=-x y ，即 1-=x y .此题比拟简单，类似例题在一般教科书上均可找到. 〔2〕xxxee f -=')(，且f(1)=0, 那么f(x)=2)(ln 21x . 【分析】先求出)(x f '的表达式，再积分即可. 【详解】令t e x=，那么t x ln =，于是有t t t f ln )(='，即 .ln )(x xx f =' 积分得 C x dx x x x f +==⎰2)(ln 21ln )(. 利用初始条件f(1)=0, 得C=0，故所求函数为f(x)=2)(ln 21x . 【评注】此题属根底题型，导函数求原函数一般用不定积分.〔3〕设L 为正向圆周222=+y x 在第一象限中的局部，那么曲线积分⎰-Lydx xdy 2的值为π23 . 【分析】利用极坐标将曲线用参数方程表示，相应曲线积分可化为定积分. 【详解】正向圆周222=+y x 在第一象限中的局部，可表示为于是θθθθθπd ydx xdy L]sin 2sin 22cos 2cos 2[220⋅+⋅=-⎰⎰=.23sin 2202πθθππ=+⎰d 【评注】此题也可添加直线段，使之成为封闭曲线，然后用格林公式计算，而在添加的线段上用参数法化为定积分计算即可.〔4〕欧拉方程)0(024222>=++x y dx dyx dxy d x 的通解为 221x c x c y +=.【分析】欧拉方程的求解有固定方法，作变量代换te x =化为常系数线性齐次微分方程即可. 【详解】令te x =，那么dtdyx dt dy e dx dt dt dy dx dy t 1==⋅=-， ][11122222222dt dydty d x dx dt dt y d x dt dy x dx y d -=⋅+-=，代入原方程，整理得02322=++y dt dydt y d ，解此方程，得通解为 .221221xc x c e c ec y t t+=+=-- 【评注】此题属根底题型，也可直接套用公式，令te x =，那么欧拉方程)(222x f cy dx dybx dx y d ax=++，可化为 ).(][22t e f cy dt dyb dt dy dty d a =++- 〔5〕设矩阵⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡=100021012A ，矩阵B 满足E BA ABA +=**2，其中*A 为A 的伴随矩阵，E 是单位矩阵，那么=B91 . 【分析】可先用公式E A A A =*进行化简【详解】等式两边同时右乘A ，得A A BA A ABA +=**2，而3=A ，于是有A B AB +=63，即 A B E A =-)63(，再两边取行列式，有363==-A B E A ，而 2763=-E A ，故所求行列式为.91=B 【评注】先化简再计算是此类问题求解的特点，而题设含有伴随矩阵*A ，一般均应先利用公式E A AA A A ==**进行化简.〔6〕设随机变量X 服从参数为λ的指数分布，那么}{DX X P >=e1 . 【分析】连续型随机变量X 的分布，求其满足一定条件的概率，转化为定积分计算即可. 【详解】由题设，知21λ=DX ，于是}{DX X P >=dx e X P x ⎰+∞-=>λλλλ1}1{=.11eex=-∞+-λλ 【评注】此题应记住常见指数分布等的期望与方差的数字特征，而不应在考试时再去推算.二、选择题〔此题共8小题，每题4分，总分值32分. 每题给出的四个选项中，只有一项符合题目要求，把所选项前的字母填在题后的括号内〕〔7〕把+→0x 时的无穷小量dt t dt t dt t xx x⎰⎰⎰===302sin ,tan ,cos 2γβα，使排在后面的是前一个的高阶无穷小，那么正确的排列次序是(A) γβα,,. (B) βγα,,. (C) γαβ,,. (D) αγβ,,. [ B ] 【分析】先两两进行比拟，再排出次序即可.【详解】 0cos 2tan lim cos tan limlim 202002=⋅==+++→→→⎰⎰x xx dtt dt t x xx x x αβ，可排除(C),(D)选项，又 xx xx dtt dtt x xxx x tan 221sin lim tan sin limlim 2300302⋅==+++→→→⎰⎰βγ=∞=+→20lim 41xxx ，可见γ是比β低阶的无穷小量，故应选(B). 【评注】此题是无穷小量的比拟问题，也可先将γβα,,分别与nx 进行比拟，再确定相互的上下次序. 〔8〕设函数f(x)连续，且,0)0(>'f 那么存在0>δ，使得(A) f(x)在〔0，)δ内单调增加. 〔B 〕f(x)在)0,(δ-内单调减少.(C) 对任意的),0(δ∈x 有f(x)>f(0) . (D) 对任意的)0,(δ-∈x 有f(x)>f(0) .[ C ]【分析】函数f(x)只在一点的导数大于零，一般不能推导出单调性，因此可排除(A),(B)选项，再利用导数的定义及极限的保号性进行分析即可.【详解】由导数的定义，知0)0()(lim)0(0>-='→xf x f f x ，根据保号性，知存在0>δ，当),0()0,(δδ -∈x 时，有即当)0,(δ-∈x 时，f(x)<f(0); 而当),0(δ∈x 时，有f(x)>f(0). 故应选(C). 【评注】题设函数一点可导，一般均应联想到用导数的定义进行讨论. 〔9〕设∑∞=1n na为正项级数，以下结论中正确的选项是(A) 假设n n na ∞→lim =0，那么级数∑∞=1n na收敛.〔B 〕假设存在非零常数λ，使得λ=∞→n n na lim ，那么级数∑∞=1n na发散.(C) 假设级数∑∞=1n na收敛，那么0lim 2=∞→n n a n .(E) 假设级数∑∞=1n na发散, 那么存在非零常数λ，使得λ=∞→n n na lim . [ B ]【分析】对于敛散性的判定问题，假设不便直接推证，往往可用反例通过排除法找到正确选项.【详解】取n n a n ln 1=，那么n n na ∞→lim =0，但∑∑∞=∞==11ln 1n n n n n a 发散，排除(A)，(D)；又取nn a n 1=，那么级数∑∞=1n n a 收敛，但∞=∞→n n a n 2lim ，排除(C), 故应选(B). 【评注】此题也可用比拟判别法的极限形式，01limlim ≠==∞→∞→λna na n n n n ，而级数∑∞=11n n 发散，因此级数∑∞=1n n a 也发散，故应选(B). 〔10〕设f(x)为连续函数，⎰⎰=t tydx x f dy t F 1)()(，那么)2(F '等于(A) 2f(2). (B) f(2). (C) –f(2). (D) 0. [ B ]【分析】先求导，再代入t=2求)2(F '即可.关键是求导前应先交换积分次序，使得被积函数中不含有变量t.【详解】交换积分次序，得⎰⎰=tt ydx x f dy t F 1)()(=⎰⎰⎰-=t x tdx x x f dx dy x f 111)1)((])([于是，)1)(()(-='t t f t F ，从而有 )2()2(f F ='，故应选(B).【评注】在应用变限的积分对变量x 求导时，应注意被积函数中不能含有变量x:否那么，应先通过恒等变形、变量代换和交换积分次序等将被积函数中的变量x 换到积分号外或积分线上.〔11〕设A 是3阶方阵，将A 的第1列与第2列交换得B,再把B 的第2列加到第3列得C, 那么满足AQ=C 的可逆矩阵Q 为(A) ⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡101001010. (B) ⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡100101010. (C) ⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡110001010. (D) ⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡100001110. [ D ]【分析】此题考查初等矩阵的的概念与性质，对A 作两次初等列变换，相当于右乘两个相应的初等矩阵，而Q 即为此两个初等矩阵的乘积.【详解】由题设，有B A =⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡100001010，C B =⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡100110001，于是， .100001110100110001100001010C A A =⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡=⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡可见，应选(D).【评注】涉及到初等变换的问题，应掌握初等矩阵的定义、初等矩阵的性质以及与初等变换的关系. 〔12〕设A,B 为满足AB=O 的任意两个非零矩阵，那么必有 (D) A 的列向量组线性相关，B 的行向量组线性相关. (E) A 的列向量组线性相关，B 的列向量组线性相关. (F) A 的行向量组线性相关，B 的行向量组线性相关.(D) A 的行向量组线性相关，B 的列向量组线性相关. [ A ]【分析】A,B 的行列向量组是否线性相关，可从A,B 是否行〔或列〕满秩或Ax=0〔Bx=0〕是否有非零解进行分析讨论.【详解1】设A 为n m ⨯矩阵，B 为s n ⨯矩阵，那么由AB=O 知，n B r A r <+)()(.又A,B 为非零矩阵，必有r(A)>0,r(B)>0. 可见r(A)<n, r(B)<n, 即A 的列向量组线性相关，B 的行向量组线性相关，故应选(A).【详解2】由AB=O 知，B 的每一列均为Ax=0的解，而B 为非零矩阵，即Ax=0存在非零解，可见A 的列向量组线性相关.同理，由AB=O 知，O A B TT=，于是有TB 的列向量组，从而B 的行向量组线性相关，故应选(A).【评注】 AB=O 是常考关系式，一般来说，与此相关的两个结论是应记住的： 1） AB=O ⇒n B r A r <+)()(; 2） AB=O ⇒B 的每列均为Ax=0的解.〔13〕设随机变量X 服从正态分布N(0,1)，对给定的)10(<<αα，数αu 满足αα=>}{u X P ，假设α=<}{x X P ，那么x 等于(A) 2αu . (B) 21α-u. (C) 21α-u . (D) α-1u . [ C ]【分析】此类问题的求解，可通过αu 的定义进行分析，也可通过画出草图，直观地得到结论. 【详解】由标准正态分布概率密度函数的对称性知，αα=-<}{u X P ，于是即有 21}{α-=≥x X P ，可见根据定义有21α-=u x ，故应选(C). 【评注】此题αu 相当于分位数，直观地有α 〔14〕设随机变量1(,,,21>n X X X n 令∑==ni i X n Y 11，那么(A) Cov(.),21nY X σ= (B) 21),(σ=Y X Cov .(C) 212)(σn n Y X D +=+. (D) 211)(σnn Y X D +=-. [ A ] 【分析】此题用方差和协方差的运算性质直接计算即可，注意利用独立性有：.,3,2,0),(1n i X X Cov i ==【详解】 Cov(∑∑==+==ni i n i i X X Cov n X X Cov n X n X Cov Y X 2111111),(1),(1)1,(),=.1121σnDX n = 【评注】此题(C),(D) 两个选项的方差也可直接计算得到：如=222233σσn n n n n +=+， =.222222σσn n n n n -=- 〔15〕〔此题总分值12分〕设2e b a e <<<, 证明)(4ln ln 222a b e a b ->-. 【分析】根据要证不等式的形式，可考虑用拉格朗日中值定理或转化为函数不等式用单调性证明. 【证法1】对函数x 2ln 在[a,b]上应用拉格朗日中值定理，得设t t t ln )(=ϕ，那么2ln 1)(t t t -='ϕ，当t>e 时， ,0)(<'t ϕ 所以)(t ϕ单调减少，从而)()(2e ϕξϕ>，即2222ln ln ee e =>ξξ，故 )(4ln ln 222a b e a b ->-. 【证法2】设x ex x 224ln )(-=ϕ，那么24ln 2)(e x x x -='ϕ， 2ln 12)(x xx -=''ϕ,所以当x>e 时，,0)(<''x ϕ 故)(x ϕ'单调减少，从而当2e x e <<时，044)()(222=-='>'ee e x ϕϕ，即当2e x e <<时，)(x ϕ单调增加.因此当2e x e <<时，)()(a b ϕϕ>，即 a ea b e b 22224ln 4ln ->-，故 )(4ln ln 222a b ea b ->-.【评注】此题也可设辅助函数为2222),(4ln ln )(e x a e a x ea x x <<<---=ϕ或 2222),(4ln ln )(e b x e x b ex b x <<<---=ϕ，再用单调性进行证明即可. 〔16〕〔此题总分值11分〕某种飞机在机场降落时，为了减少滑行距离，在触地的瞬间，飞机尾部张开减速伞，以增大阻力，使飞机迅速减速并停下.现有一质量为9000kg 的飞机，着陆时的水平速度为700km/h. 经测试，减速伞翻开后，飞机所受的总阻力与飞机的速度成正比〔比例系数为).100.66⨯=k 问从着陆点算起，飞机滑行的最长距离是多少？注kg 表示千克，km/h 表示千米/小时.【分析】此题是标准的牛顿第二定理的应用，列出关系式后再解微分方程即可.【详解1】由题设，飞机的质量m=9000kg ，着陆时的水平速度h km v /7000=. 从飞机接触跑道开始记时，设t 时刻飞机的滑行距离为x(t)，速度为v(t).根据牛顿第二定律，得kv dtdv m-=. 又 dx dv v dt dx dx dv dt dv =⋅=，由以上两式得dv k m dx -=，积分得 .)(C v k m t x +-= 由于0)0(,)0(0==x v v ，故得0v km C =，从而当0)(→t v 时， ).(05.1100.67009000)(60km k mv t x =⨯⨯=→所以，飞机滑行的最长距离为1.05km.【详解2】根据牛顿第二定律，得 kv dt dv m-=, 所以 .dt mk v dv -= 两端积分得通解t m k Cev -=，代入初始条件00v v t ==解得0v C =，故 .)(0t m k e v t v -=飞机滑行的最长距离为或由t m ke v dt dx -=0，知)1()(000--==--⎰t m k t t m k e m kv dt e v t x ，故最长距离为当∞→t 时，).(05.1)(0km mkv t x =→ 【详解3】根据牛顿第二定律，得 dt dx k dtx d m -=22, 022=+dt dx m k dtx d ，其特征方程为 02=+λλm k ，解之得mk -==21,0λλ，故 .21t mk e C C x -+= 由 002000,0v e m kC dt dx v x t t mk t t t =-====-===，得 ,021k mv C C =-= 于是 ).1()(0t m ke k mv t x --=当+∞→t 时，).(05.1)(0km kmv t x =→ 所以，飞机滑行的最长距离为1.05km.【评注】此题求飞机滑行的最长距离，可理解为+∞→t 或0)(→t v 的极限值，这种条件应引起注意. 〔17〕〔此题总分值12分〕计算曲面积分其中∑是曲面)0(122≥--=z y x z 的上侧.【分析】先添加一曲面使之与原曲面围成一封闭曲面，应用高斯公式求解，而在添加的曲面上应用直接投影法求解即可.【详解】取1∑为xoy 平面上被圆122=+y x 所围局部的下侧，记Ω为由∑与1∑围成的空间闭区域，那么由高斯公式知=rdz r z dr d r )(620101022⎰⎰⎰-+πθ=.2)]1()1(21[12232210ππ=-+-⎰dr r r r r 而 ⎰⎰⎰⎰≤+∑=--=-++123322133)1(322y x dxdy dxdy zdzdx y dydz x π，故 .32πππ-=-=I【评注】此题选择1∑时应注意其侧与∑围成封闭曲面后同为外侧〔或内侧〕，再就是在1∑上直接投影积分时，应注意符号(1∑取下侧，与z 轴正向相反，所以取负号).〔18〕〔此题总分值11分〕设有方程01=-+nx x n ，其中n 为正整数. 证明此方程存在惟一正实根n x ，并证明当1>α时，级数∑∞=1n nx α收敛. 【分析】利用介值定理证明存在性，利用单调性证明惟一性.而正项级数的敛散性可用比拟法判定.【证】记 .1)(-+=nx x x f n n 由01)0(<-=n f ，0)1(>=n f n ，及连续函数的介值定理知，方程01=-+nx x n 存在正实数根).1,0(∈n x当x>0时，0)(1>+='-n nx x f n n ，可见)(x f n 在),0[+∞上单调增加, 故方程01=-+nx x n 存在惟一正实数根.n x由01=-+nx x n 与0>n x 知n n x x n n n 110<-=<，故当1>α时，αα)1(0nx n <<. 而正项级数∑∞=11n n α收敛，所以当1>α时，级数∑∞=1n n x α收敛.【评注】此题综合考查了介值定理和无穷级数的敛散性，题型设计比拟新颖，但难度并不大，只要根本概念清楚，应该可以轻松求证.〔19〕〔此题总分值12分〕设z=z(x,y)是由0182106222=+--+-z yz y xy x 确定的函数，求),(y x z z =的极值点和极值.【分析】可能极值点是两个一阶偏导数为零的点，先求出一阶偏导，再令其为零确定极值点即可，然后用二阶偏导确定是极大值还是极小值，并求出相应的极值.【详解】因为 0182106222=+--+-z yz y xy x ，所以02262=∂∂-∂∂--xz z x z y y x ， 0222206=∂∂-∂∂--+-y z z y z yz y x . 令 ⎪⎪⎩⎪⎪⎨⎧=∂∂=∂∂0,0y z x z 得 ⎩⎨⎧=-+-=-,0103,03z y x y x 故 ⎩⎨⎧==.,3y z y x 将上式代入0182106222=+--+-z yz y xy x ，可得 ⎪⎩⎪⎨⎧===3,3,9z y x 或⎪⎩⎪⎨⎧-=-=-=.3,3,9z y x 由于 02)(22222222=∂∂-∂∂-∂∂-xz z x z x z y ， 02)(22222022222=∂∂-∂∂-∂∂-∂∂-∂∂-yz z y z y z y y z y z ，所以 61)3,3,9(22=∂∂=x z A ，21)3,3,9(2-=∂∂∂=y x z B ，35)3,3,9(22=∂∂=y z C ，故03612>=-B AC ，又061>=A ，从而点(9,3)是z(x,y)的极小值点，极小值为z(9,3)=3. 类似地，由 61)3,3,9(22-=∂∂=---x z A ，21)3,3,9(2=∂∂∂=---y x z B ，35)3,3,9(22-=∂∂=---y z C ，可知03612>=-B AC ，又061<-=A ，从而点(-9, -3)是z(x,y)的极大值点，极大值为 z(-9, -3)= -3.【评注】此题讨论由方程所确定的隐函数求极值问题，关键是求可能极值点时应注意x,y,z 满足原方程.〔20〕〔此题总分值9分〕设有齐次线性方程组试问a 取何值时，该方程组有非零解，并求出其通解.【分析】此题是方程的个数与未知量的个数相同的齐次线性方程组，可考虑对系数矩阵直接用初等行变换化为阶梯形，再讨论其秩是否小于n ，进而判断是否有非零解；或直接计算系数矩阵的行列式，根据题设行列式的值必为零，由此对参数a 的可能取值进行讨论即可.【详解1】对方程组的系数矩阵A 作初等行变换，有当a=0时， r(A)=1<n ，故方程组有非零解，其同解方程组为由此得根底解系为于是方程组的通解为,1111--++=n n k k x ηη 其中11,,-n k k 为任意常数.当0≠a 时，对矩阵B 作初等行变换，有可知2)1(+-=n n a 时，n n A r <-=1)(，故方程组也有非零解，其同解方程组为由此得根底解系为 T n ),,2,1( =η，于是方程组的通解为ηk x =，其中k 为任意常数.【详解2】方程组的系数行列式为1)2)1((22221111-++=+++=n a n n a an n n n aaA. 当0=A ，即a=0或2)1(+-=n n a 时，方程组有非零解. 当a=0时，对系数矩阵A 作初等行变换，有⎥⎥⎥⎥⎦⎤⎢⎢⎢⎢⎣⎡→⎥⎥⎥⎥⎦⎤⎢⎢⎢⎢⎣⎡=000000000111122221111 n n n n A ，故方程组的同解方程组为由此得根底解系为于是方程组的通解为,1111--++=n n k k x ηη 其中11,,-n k k 为任意常数. 当2)1(+-=n n a 时，对系数矩阵A 作初等行变换，有 ⎥⎥⎥⎥⎦⎤⎢⎢⎢⎢⎣⎡--→⎥⎥⎥⎥⎦⎤⎢⎢⎢⎢⎣⎡--+→1000012000010000121111 n n a ，故方程组的同解方程组为由此得根底解系为Tn ),,2,1( =η，于是方程组的通解为ηk x =，其中k 为任意常数.【评注】矩阵A 的行列式A 也可这样计算： ⎥⎥⎥⎥⎦⎤⎢⎢⎢⎢⎣⎡+++=a n n n n a a A 22221111=aE +⎥⎥⎥⎥⎦⎤⎢⎢⎢⎢⎣⎡n n n n 22221111，矩阵⎥⎥⎥⎥⎦⎤⎢⎢⎢⎢⎣⎡n n n n 22221111的特征值为2)1(,0,,0+n n ，从而A 的特征值为a,a,2)1(,++n n a , 故行列式.)2)1((1-++=n a n n a A 〔21〕〔此题总分值9分〕设矩阵⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡---=51341321a A 的特征方程有一个二重根，求a 的值，并讨论A 是否可相似对角化. 【分析】先求出A 的特征值，再根据其二重根是否有两个线性无关的特征向量，确定A 是否可相似对角化即可.【详解】 A 的特征多项式为=).3188)(2(51341011)2(2a a ++--=------λλλλλλ 当2=λ是特征方程的二重根，那么有,03181622=++-a 解得a= -2.当a= -2时，A 的特征值为2,2,6, 矩阵2E-A=⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡----321321321的秩为1，故2=λ对应的线性无关的特征向量有两个，从而A 可相似对角化.假设2=λ不是特征方程的二重根，那么a 31882++-λλ为完全平方，从而18+3a=16，解得 .32-=a 当32-=a 时，A 的特征值为2，4，4，矩阵4E-A=⎥⎥⎥⎥⎦⎤⎢⎢⎢⎢⎣⎡---1321301323秩为2，故4=λ对应的线性无关的特征向量只有一个，从而A 不可相似对角化.【评注】 n 阶矩阵A 可对角化的充要条件是：对于A 的任意i k 重特征根i λ，恒有.)(i i k A E r n =--λ 而单根一定只有一个线性无关的特征向量.(22)〔此题总分值9分〕设A,B 为随机事件，且21)(,31)(,41)(===B A P A B P A P ，令求：〔I 〕二维随机变量(X,Y)的概率分布；〔II 〕X 和Y 的相关系数.XY ρ【分析】先确定(X,Y)的可能取值，再求在每一个可能取值点上的概率，而这可利用随机事件的运算性质得到，即得二维随机变量(X,Y)的概率分布；利用联合概率分布可求出边缘概率分布，进而可计算出相关系数.【详解】〔I 〕由于121)()()(==A B P A P AB P ，所以， 121)(}1,1{====AB P Y X P ， 61)()()(}0,1{=-====AB P A P B A P Y X P ， =32)()()(1=+--AB P B P A P 〔或32121611211}0,0{=---===Y X P 〕，故(X,Y)的概率分布为YX 0 10 32 121 1 61 121 (II) X, Y 的概率分布分别为X 0 1 Y 0 1P43 41 P 65 61 那么61,41==EY EX ，163=DX ，DY=365, E(XY)=121, 故 241)(),(=⋅-=EY EX XY E Y X Cov ，从而【评注】此题尽管难度不大，但考察的知识点很多，综合性较强.通过随机事件定义随机变量或通过随机变量定义随机事件，可以比拟好地将概率论的知识前后连贯起来，这种命题方式值得注意.〔23〕〔此题总分值9分〕设总体X 的分布函数为其中未知参数n X X X ,,,,121 >β为来自总体X 的简单随机样本，求：〔I 〕 β的矩估计量；〔II 〕 β的最大似然估计量.【分析】先由分布函数求出概率密度，再根据求矩估计量和最大似然估计量的标准方法进行讨论即可.【详解】 X 的概率密度为〔I 〕由于1);(11-=⋅==⎰⎰+∞++∞∞-βββββdx x x dx x xf EX ，令X =-1ββ，解得 1-=X X β，所以参数β的矩估计量为〔II 〕似然函数为当),,2,1(1n i x i =>时，0)(>βL ，取对数得∑=+-=ni i x n L 1ln )1(ln )(ln βββ，两边对β求导，得∑=-=n i i x n d L d 1ln )(ln βββ，令0)(ln =ββd L d ，可得 ∑==n i ixn 1ln β，故β的最大似然估计量为【评注】此题是根底题型，难度不大，但计算量比拟大，实际做题时应特别注意计算的准确性.。

2004年全国攻读硕士学位研究生入学考试英语试题

2004年全国攻读硕士学位研究生入学考试英语试题Section I Use of EnglishDirections：Read the following text. Choose the best word(s) for each numbered blank and mark A, B, C or D on ANSWER SHEET 1. (10 points)Many theories concerning the causes of juvenile delinquency (crimes committed by young people) focus either on the individual or on society as the major contributing influence. Theories 1 on the individual suggest that children engage in criminal behavior 2 they were not sufficiently penalized for previous misdeeds or that they have learned criminal behavior through 3 with others. Theories focusing on the role of society suggest that children commit crimes in 4 to their failure to rise above their socioeconomic status, 5 as a rejection of middle-class values.Most theories of juvenile delinquency have focused on children from disadvantaged families, _ 6 the fact that children from wealthy homes also commit crimes. The latter may commit crimes 7 lack of adequate parental control. All theories, however, are tentative and are 8 to criticism.Changes in the social structure may indirectly 9 juvenile crime rates. For example, changes in the economy that 10 to fewer job opportunities for youth and rising unemployment 11 make gainful employment increasingly difficult to obtain. The resulting discontent may in 12 lead more youths into criminal behavior.Families have also 13 changes these years. More families consist of one-parent households or two working parents; 14 ，children are likely to have less supervision at home 15 was common in the traditional family 16 . This lack of parental supervision is thought to be an influence on juvenile crime rates. Other __17_ causes of offensive acts include frustration or failure in school, the increased __ 18 _ of drugs and alcohol, and the growing 19 of child abuse and child neglect. All these conditions tend to increase the probability of a child committing a criminal act, 20 a direct causal relationship has not yet been established.1. [A] acting [B] relying [C] centering [D] commenting2. [A] before [B] unless [C] until [D] because3. [A] interaction [B] assimilation [C] cooperation [D]consultation4. [A] return [B] reply [C] reference [D] response5. [A] or [B] but rather [C] but [D] or else6. [A] considering [B] ignoring [C] highlighting [D] discarding7. [A] on [B] in [C] for [D] with8. [A] immune [B] resistant [C] sensitive [D] subject9. [A] affect [B] reduce [C] chock [D] reflect10. [A] point [B] lead [C] come [D] amount11. [A] in general [B] on average [C] by contrast [D] at length12. [A] case [B] short [C] turn [D] essence13. [A] survived [B] noticed [C] undertaken [D] experienced14.[A] contrarily [B] consequently [C] similarly [D] simultaneously15. [A] than [B] that [C] which [D] as16. [A] system [B] structure [C] concept [D] heritage17. [A] assessable [B] identifiable [C] negligible [D] incredible18. [A] expense [B] restriction [C] allocation [D] availability19. [A] incidence [B] awareness [C] exposure [D] popularity20. [A] provided [B] since [C] although [D] supposingSection II Reading ComprehensionPart ADirections:Read the following four texts. Answer the questions below each text by choosing [A], [B], [C] or [D]. Mark your answers on ANSWER SHEET 1.(40 points)Text 1Hunting for a job late last year, lawyer Gant Redmon stumbled across CareerBuilder, a job database on the Internet. He searched it with no success but was attracted by t he site’s “per sonal search agent”. It’s an interactive feature that lets visitors key in job criteria such as location, title, and salary, then E-mails them when a matching position is posted in the database. Redmon chose the keywords legal, intellectual property and Washington, D.C.Three weeks later, he got his first notification of an opening. “I struck gold,” says Red mon, who E-mailed his resume to the employer and won a position as in-house counsel for a company.With thousands of career-related sites on the Internet, finding promising openings can he time-consuming and inefficient. Search agents reduce the need for repeated visits to the databases. But although a search agent worked for Redmon, career experts see drawbacks. Narrowing your criteria, for example, may work against you: “Every time you answer a question you el iminate a possibility,” says one expert.For any job search, you should start with a narrow concept—what you think you want to do—then broaden it. “None of these programs do that,” says another expert. “There’s no career counseling implicit in all of this.” Instead, the best strategy is to use the agent as a kind of tip service to keep abreast of jobs in a particular database; when you get E-m ail, consider it a reminder to check the database again. “I would not rely on agents for finding everything that is added to a database that might interest me,” says the author of a job-searching guide.Some sites design their agents to tempt job hunters to return. When CareerSite’s agent sends out messages to those who have signed up for its service, for example, it includes only three potential jobs—those it considers the best matches. There may be more matches in the database; job hunters will have to visit the site again to find them—and they do. “On the day after we send our messages, we see a sharp increase in our traffic,” says Seth Peets, vice president of marketing for CareerSite.Even those who aren’t hunting for jobs may find search agents worthwhile. Some use them to keep a close watch on the demand for their line of work or gather information on compensation to arm themselves when negotiating for a raise. Although happily employed, Redmon maintains his agent at CareerBuilder. “You always keep your eyes open,” he says. Working with a personal search agent means having another set of eyes looking out for you.21. How did Redmon find his job?[A] By searching openings in a job database.[B] By posting a matching position in a database.[C] By using a special service of a database.[D] By E-mailing his resume to a database.22. Which of the following can be a disadvantage of search agents?[A] Lack of counseling. [B] Limited number of visits.[C] Lower efficiency. [D] Fewer successful matches.23. The expression “tip service” (Line 4, Paragraph 3) most probablymeans .[A] advisory. [B] compensation.[C] interaction. [D] reminder.24. Why does CareerSite’s agent offer each job hunter only three joboptions?[A] To focus on better job matches.[B] To attract more returning visits.[C] To reserve space for more messages.[D] To increase the rate of success.25. Which of the following is true according to the text?[A] Personal search agents are indispensable to job-hunters.[B] Some sites keep E-mailing job seekers to trace their demands.[C] Personal search agents are also helpful to those already employed.[D] Some agents stop sending information to people once they areemployed.Text 2Over the past century, all kinds of unfairness and discrimination have been condemned or made illegal. But one insidious form continues to thrive: alphabetism. This, for those as yet unaware of such a disadvantage, refers to discrimination against those whose surnames begin with a letter in the lower half of the alphabet.It has long been known that a taxi firm called AAAA cars has a big advantage over Zodiac cars when customers thumb through their phone directories. Less well known is the advantage that Adam Abbott has in life over Zoë Zysman. English names are fairly evenly spread between the halves of the alphabet. Yet a suspiciously large number of top people have surnames beginning with letters between A and K.Thus the American president and vice-president have surnames starting with B and C respectively; and 26 of George Bush’s predecessors (including his father) had surnames in the first half of the alphabet against just 16 in the second half. Even more striking, six of the seven heads of government of the G7 rich countries are alphabetically advantaged (Berlusconi, Blair, Bush, Chirac, Chrétien and Koizumi). The world’s three top central bankers (Greenspan, Duisenberg and Hayami) are all close to the top of the alphabet, even if one of them really uses Japanesecharacters. As are the world's five richest men (Gates, Buffett, Allen, Ellison and Albrecht).Can this merely be coincidence? One theory, dreamt up in all the spare time enjoyed by the alphabetically disadvantaged, is that the rot sets in early. At the start of the first year in infant school, teachers seat pupils alphabetically from the front, to make it easier to remember their names. So short-sighted Zysman junior gets stuck in the back row, and is rarely asked the improving questions posed by those insensitive teachers. At the time the alphabetically disadvantaged may think they have had a lucky escape. Yet the result may be worse qualifications, because they get less individual attention, as well as less confidence in speaking publicly.The humiliation continues. At university graduation ceremonies, the ABCs proudly get their awards first; by the time they reach the Zysmans most people are literally having a ZZZ. Shortlists for job interviews, election ballot papers, lists of conference speakers and attendees: all tend to be drawn up alphabetically, and their recipients lose interest as they plough through them.26. What does the author intend to illustrate with AAAA cars and Zodiaccars?[A] A kind of overlooked inequality.[B] A type of conspicuous bias.[C] A type of personal prejudice.[D] A kind of brand discrimination.27. What can we infer from the first three paragraphs?[A] In both East and West, names are essential to success.[B] The alphabet is to blame for the failure of Zoë Zysman.[C] Customers often pay a lot of attention to companies’ names.[D] Some form of discrimination is too subtle to recognize.28. The 4th paragraph suggests that .[A] questions are often put to the more intelligent students[B] alphabetically disadvantaged students often escape from class[C] teachers should pay attention to all of their students[D] students should be seated according to their eyesight29. What does the author mean by “most people are literally having a ZZZ”(Lines 2-3, Paragraph 5)?[A] They are getting impatient.[B] They are noisily dozing off.[C] They are feeling humiliated.[D] They are busy with word puzzles.30. Which of the following is true according to the text?[A] People with surnames beginning with N to Z are often ill-treated.[B] VIPs in the Western world gain a great deal from alphabetism.[C] The campaign to eliminate alphabetism still has a long way to go.[D] Putting things alphabetically may lead to unintentional bias.Text 3When it comes to the slowing economy, Ellen Spero isn't biting her nails just yet. But the 47-year-old manicurist isn't cutting, filing or polishing as many nails as she'd like to, either. Most of her clients spend $12 to $50 weekly, but last month two longtime customers suddenly stopped showing up. Spero blames the softening economy. “I'm a good economic indicator,” she says. “I provide a service that people can do without when they're concerned about saving some dollars.” So Spero is downscaling, shopping at middle-brow Dillard's department store near her suburban Cleveland home, instead of Neiman Marcus. “I don't know if othe r clients are going to abandon me, too,” she says.Even before Alan Greenspan's admission that America's red-hot economy is cooling, lots of working folks had already seen signs of the slowdown themselves. From car dealerships to Gap outlets, sales have been lagging for months as shoppers temper their spending. For retailers, who last year took in 24 percent of their revenue between Thanksgiving and Christmas, the cautious approach is coming at a crucial time. Already, experts say, holiday sales are off 7 percent from last year's pace. But don't sound any alarms just yet. Consumers seem only mildly concerned, not panicked, and many say they remain optimistic about the economy's long-term prospects even as they do some modest belt-tightening.Consumers say they're not in despair because, despite the dreadful headlines, their own fortunes still feel pretty good. Home prices are holding steady in most regions. In Manhattan, “there's a new gold rush happening in the $4 million to $10 million range, predominantly fed by Wall Street bonuses,” says broker Barbara Corcoran. In San Francisco, prices are still rising even as frenzied overbidding quiets. “Instead of 20 to 30 offers, now maybe you only get two or three," says John Tealdi, a Bay Area real-estate broker. And most folks still feel pretty comfortable about their ability to find and keep a job.Many folks see silver linings to this slowdown. Potential home buyers would cheer for lower interest rates. Employers wouldn't mind a little fewer bubbles in the job market. Many consumers seem to have been influenced by stock-market swings, which investors now view as a necessary ingredient to a sustained boom. Diners might see an upside, too. Getting a table at Manhattan's hot new Alain Ducasse restaurant used to be impossible. Not anymore. For that, Greenspan & Co. may still be worth toasting.31. By “Ellen Spero isn’t biting her nails just yet” (Line 1, Paragraph1), the author means_____.[A] Spero can hardly maintain her business.[B] Spero is too much engaged in her work.[C] Spero has grown out of her bad habit.[D] Spero is not in a desperate situation.32. How do the public feel about the current economic situation?[A] Optimistic. [B] Confused. [C] Carefree. [D] Panicked.33. When mentioning “the $4 million to $10 million range”(Lines 3,Paragraph 3), the author is talking about _______[A] gold market.[B] real estate.[C] stock exchange.[D] venture investment.34. Why can many people see “silver linings” to the economic slowdown?[A] They would benefit in certain ways.[B] The stock market shows signs of recovery.[C] Such a slowdown usually precedes a boom.[D] The purchasing power would be enhanced.35. To which of the following is the author likely to agree?[A] A new boom, on the horizon.[B] Tighten the belt, the single remedy.[C] Caution all right, panic not.[D] The more ventures, the more chances.Text 4Americans today don't place a very high value on intellect. Our heroes are athletes, entertainers, and entrepreneurs, not scholars. Even our schools are where we send our children to get a practical education—not to pursue knowledge for the sake of knowledge. Symptoms of pervasive anti-intellectualism in our schools aren't difficult to find.“Schools have always been in a societ y where practical is more important than intellectual,” says education writer Diane Ravitch. “Schools could be a counterbalance.” Ravitch's latest book. Left Back: A Century of Failed School Reforms,traces the roots of anti-intellectualism in our schools, concluding they are anything but a counterbalance to the American distaste for intellectual pursuits.But they could and should be. Encouraging kids to reject the life of the mind leaves them vulnerable to exploitation and control. Without the ability to think critically, to defend their ideas and understand the ideas of others, they cannot fully participate in our democracy. Continuing along this path, says writer Earl Shorris, “We will become a second-rate country. We will have a less civil society.”“Intellect is resented as a form of power or privilege,” writes historian and professor Richard Hofstadter in Anti-intellectualism in American Life, a Pulitzer-Prize winning book on the roots of anti-intellectualism in US politics, religion, and education. From the beginning of our history, says Hofstadter, our democratic and populist urges have driven us to reject anything that smells of elitism. Practicality, common sense, and native intelligence have been considered more noble qualities than anything you could learn from a book.Ralph Waldo Emerson and other Transcendentalist philosophers thought schooling and rigorous book learning put unnatural restraints on children: “We are shut up in schools and college recitation rooms for 10 or 15 years and come out at last with a bellyful of words and do not know a thing.”Mark Twain's Huckleberry Finn exemplified American anti-intellectualism. Its hero avoids being civilized—going to school and learning to read—so he can preserve his innate goodness.Intellect, according to Hofstadter, is different from native intelligence, a quality we reluctantly admire. Intellect is the critical, creative, and contemplative side of the mind. Intelligence seeks to grasp, manipulate, re-order, and adjust, while intellect examines, ponders, wonders, theorizes, criticizes, and imagines.School remains a place where intellect is mistrusted. Hofstadter says our country's educational system is in the grips of people who “joyfully and militantly proclaim their hostility to intellect and their eagerness to identify with children who show the least intellectual promise.”36. What do American parents expect their children to acquire in school?[A] The habit of thinking independently.[B] Profound knowledge of the world.[C] Practical abilities for future career.[D] The confidence in intellectual pursuits.37. We can learn from the text that Americans have a history of________.[A] undervaluing intellect.[B] favoring intellectualism.[C] supporting school reform.[D] suppressing native intelligence.38. The views of Raviteh and Emerson on schooling are ______.[A] identical. [B] similar. [C] complementary. [D] opposite.39. Emerson, according to the text, is probably _________.[A] a pioneer of education reform.[B] an opponent of intellectualism.[C] a scholar in favor of intellect.[D] an advocate of regular schooling.40. What does the author think of intellect?[A] It is second to intelligence.[B] It evolves from common sense.[C] It is to be pursued.[D] It underlies powerPart BDirections:Read the following text carefully and then translate the underlined segments into Chinese. Your translation should be written clearly on ANSWER SHEET 2. (10 points)The relation of language and mind has interested philosophers for many centuries. (41) The Greeks assumed that the structure of language had some connection with the process of thought, which took root in Europe long before people realized how diverse languages could be.Only recently did linguists begin the serious study of languages that were very different from their own. Two anthropologist-linguists, Franz Boas and Edward Sapir, were pioneers in describing many native languages of North and South America during the first half of the twentieth century.(42) We are obliged to them because some of these languages have since vanished, as the peoples who spoke them died out or became assimilated and lost their native languages. Other linguists in the earlier part of this century, however, who were less eager to deal with bizarre data from “exotic” language, were not always so grateful. (43) The newly described languages were often so strikingly different from the well studied languages of Europe and Southeast Asia that some scholars even accused Boas and Sapir of fabricating their data. Native American languages are indeed different, so much so in fact that Navajo could be used by the US military as a code during World War II to send secret messages.Sapir’s pupil, Benjamin Lee Whorf, continued the study of American Indian languages. (44) Being interested in the relationship of language and thought, Whorf developed the idea that the structure of language determines the structure of habitual thought in a society. He reasoned that because it is easier to formulate certain concepts and not others in a given language, the speakers of that language think along one track and not along another. (45) Whorf came to believe in a sort of linguistic determinism which, in its strongest form, states that language imprisons the mind, and that the grammatical patterns in a language can produce far-reaching consequences for the culture of a society. Later, this idea became to be known as the Sapir-Whorf hypothesis, but this term is somewhat inappropriate. Although both Sapir and Whorf emphasized the diversity of languages, Sapir himself never explicitly supported the notion of linguistic determinism.Section III Writing46. Directions：Study the following drawing carefully and write an essay in which you should1. describe the drawing，2. interpret its meaning, and3. support your view with examples.You should write about 200 words neatly on ANSWER SHEET 2 (20 points)2004考研英语一解析第一部分英语知识运用试题解析一、文章总体分析文章主要探讨青少年犯罪的原因。

【数学三】2004年全国硕士研究生入学统一考试真题

2004年考研数学（三）真题一、填空题（本题共6小题，每小题4分，满分24分. 把答案填在题中横线上）(1) 若5)(cos sin lim 0=--→b x ae x x x ，则a =______，b =______. (2) 设函数f (u , v )由关系式f [xg (y ) , y ] = x + g (y )确定，其中函数g (y )可微，且g (y ) ≠ 0，则2f u v∂=∂∂. (3) 设⎪⎩⎪⎨⎧≥-<≤-=21,12121,)(2x x xe x f x ，则212(1)f x dx -=⎰.(4) 二次型213232221321)()()(),,(x x x x x x x x x f ++-++=的秩为 .(5) 设随机变量X 服从参数为λ的指数分布, 则=>}{DX X P _______.(6) 设总体X 服从正态分布),(21σμN , 总体Y 服从正态分布),(22σμN ,1,,21n X X X 和 2,,21n Y Y Y 分别是来自总体X 和Y 的简单随机样本, 则12221112()()2n n i j i j X X Y Y E n n ==⎡⎤-+-⎢⎥⎢⎥=⎢⎥+-⎢⎥⎢⎥⎣⎦∑∑.二、选择题（本题共6小题，每小题4分，满分24分. 每小题给出的四个选项中，只有一项符合题目要求，把所选项前的字母填在题后的括号内）(7) 函数2)2)(1()2sin(||)(---=x x x x x x f 在下列哪个区间内有界. (A) (-1 , 0).(B) (0 , 1). (C) (1 , 2). (D) (2 , 3). [ ] (8) 设f (x )在(-∞ , +∞)内有定义，且a x f x =∞→)(lim ， ⎪⎩⎪⎨⎧=≠=0,00,)1()(x x x f x g ，则 (A) x = 0必是g (x )的第一类间断点. (B) x = 0必是g (x )的第二类间断点.(C) x = 0必是g (x )的连续点.(D) g (x )在点x = 0处的连续性与a 的取值有关. [ ](9) 设f (x ) = |x (1 - x )|，则(A) x = 0是f (x )的极值点，但(0 , 0)不是曲线y = f (x )的拐点.(B) x = 0不是f (x )的极值点，但(0 , 0)是曲线y = f (x )的拐点.(C) x = 0是f (x )的极值点，且(0 , 0)是曲线y = f (x )的拐点.(D) x = 0不是f (x )的极值点，(0 , 0)也不是曲线y = f (x )的拐点. [ ](10) 设有下列命题：(1) 若∑∞=-+1212)(n n n u u 收敛，则∑∞=1n n u 收敛.(2) 若∑∞=1n n u 收敛，则∑∞=+11000n n u 收敛.(3) 若1lim 1>+∞→n n n u u ，则∑∞=1n n u 发散.(4) 若∑∞=+1)(n n n v u 收敛，则∑∞=1n n u ，∑∞=1n n v 都收敛.则以上命题中正确的是(A) (1) (2). (B) (2) (3). (C) (3) (4). (D) (1) (4). [ ](11) 设)(x f '在[a , b]上连续，且0)(,0)(<'>'b f a f ，则下列结论中错误的是(A) 至少存在一点),(0b a x ∈，使得)(0x f > f (a ).(B) 至少存在一点),(0b a x ∈，使得)(0x f > f (b ).(C) 至少存在一点),(0b a x ∈，使得0)(0='x f .(D) 至少存在一点),(0b a x ∈，使得)(0x f = 0. [ D ](12) 设n 阶矩阵A 与B 等价, 则必有(A) 当)0(||≠=a a A 时, a B =||. (B) 当)0(||≠=a a A 时, a B -=||.(C) 当0||≠A 时, 0||=B . (D) 当0||=A 时, 0||=B . [ ](13) 设n 阶矩阵A 的伴随矩阵,0*≠A 若4321,,,ξξξξ是非齐次线性方程组 b Ax =的互不相等的解，则对应的齐次线性方程组0=Ax 的基础解系(A) 不存在. (B) 仅含一个非零解向量.(C) 含有两个线性无关的解向量. (D) 含有三个线性无关的解向量. [ ](14) 设随机变量X 服从正态分布)1,0(N , 对给定的)1,0(∈α, 数αu 满足αu X P α=>}{,若αx X P =<}|{|, 则x 等于(A) 2αu . (B) 21αu -. (C) 21αu -.(D) αu -1. [ ]三、解答题(本题共9小题，满分94分. 解答应写出文字说明、证明过程或演算步骤.)(15) (本题满分8分)求)cos sin 1(lim 2220x xx x -→.(16) (本题满分8分)求⎰⎰++Dd y y x σ)(22，其中D 22122=所围成的平面区域(如图).(17) (本题满分8分)设f (x ) , g (x )在[a , b ]上连续，且满足⎰⎰≥xa x a dt t g dt t f )()(，x ∈ [a ,b )，⎰⎰=ba b a dt t g dt t f )()(.证明：⎰⎰≤ba ba dx x xg dx x xf )()(.(18) (本题满分9分)设某商品的需求函数为Q = 100 - 5P ，其中价格P ∈ (0 , 20)，Q 为需求量.(I) 求需求量对价格的弹性d E (d E > 0)；(II) 推导)1(d E Q dP dR-=(其中R 为收益)，并用弹性d E 说明价格在何范围内变化时，降低价格反而使收益增加.(19) (本题满分9分)设级数)(864264242864+∞<<-∞+⋅⋅⋅+⋅⋅+⋅x x x x的和函数为S (x ). 求：(I) S (x )所满足的一阶微分方程；(II) S (x )的表达式.(20)(本题满分13分)设T α)0,2,1(1=, T ααα)3,2,1(2-+=, T b αb α)2,2,1(3+---=, Tβ)3,3,1(-=, 试讨论当b a ,为何值时,(Ⅰ) β不能由321,,ααα线性表示;(Ⅱ) β可由321,,ααα唯一地线性表示, 并求出表示式;(Ⅲ) β可由321,,ααα线性表示, 但表示式不唯一, 并求出表示式.(21) (本题满分13分)设n 阶矩阵⎪⎪⎪⎪⎪⎭⎫ ⎝⎛=111 b b bb b b A .(Ⅰ) 求A 的特征值和特征向量;(Ⅱ) 求可逆矩阵P , 使得AP P 1-为对角矩阵.(22) (本题满分13分)设A ，B 为两个随机事件,且41)(=A P , 31)|(=A B P , 21)|(=B A P , 令⎩⎨⎧=不发生，，发生，A A X 0,1 ⎩⎨⎧=.0,1不发生，发生，B B Y求(Ⅰ) 二维随机变量),(Y X 的概率分布;(Ⅱ) X 与Y 的相关系数 XY ρ;(Ⅲ) 22Y X Z +=的概率分布.(23) (本题满分13分)设随机变量X 的分布函数为⎪⎩⎪⎨⎧≤>⎪⎭⎫⎝⎛-=，，，αx αx x αβαx F β0,1),,(其中参数1,0>>βα. 设n X X X ,,,21 为来自总体X 的简单随机样本,(Ⅰ) 当1=α时, 求未知参数β的矩估计量;(Ⅱ) 当1=α时, 求未知参数β的最大似然估计量; (Ⅲ) 当2=β时, 求未知参数α的最大似然估计量.。

2004年考研英语一真题答案解析

2004年全国攻读硕士学位研究生入学考试英语答案及解析第一部分英语知识运用试题解析一、文章总体分析文章主要探讨青少年犯罪的原因。

一开始，文章从现有的理论出发，指出这些理论集中把个人或社会看作主要影响因素。

接着文章又进一步谈到，现有理论只关注来自贫穷家庭的孩子，而忽视了来自富有家庭的孩子也犯罪这一事实。

总之，这些理论都是不确定的，容易受到批评和攻击。

从第三段开始，文章提出了新的见解：社会结构的变化可能间接地影响了青少年犯罪率。

这其中包括经济结构和家庭结构的变化。

除此之外，也有其他一些原因造成了青少年的犯罪行为。

最后，文章就以上提到的众多原因作了一个总结：所有上述情形都有可能促使青少年犯罪，但它们与青少年犯罪是否存在直接的因果关系还没有确定。

二、试题具体解析1. [A] acting (on) 对……起作用[B]relying (on) 依靠，指望[C]centering (on) 以……为中心，围绕；集中于……[D]commenting (on) 对……做出评论[答案] C[解析] 本题考核的知识点是：平行句子结构+分词短语辨析。

本题要求考生判断空格处应填入什么分词与on搭配，构成分词短语。

从结构上看，文章第一段由三个平行结构的长句子构成，其主要结构为Many theories concerning…focus on；Theories 1 on the individual suggest that；Theories focusing on the role of society suggest that。

三个句子的主语都是 theories，并都接有分词作定语。

因此空格处填入的分词应和前一句中的concerning、后一句中的focusing on遥相呼应，都表示“关于…的理论”的含义，从文意方面看，第一句话总述到，关于（concerning）青少年犯罪原由的理论集中研究两个方面，即个人因素和社会因素。

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东北大学2004年攻读硕士学位研究生试题
考试科目：化工原理
1概念题（任选8题，每题5分，计40分）
1.1聚式流态化
1.6深层过滤
1.2流动边界层
1.7等摩尔扩散
1.3助滤剂
1.8数学模型方法
1.4漂流因子
1.9离心泵的理论压头
1.5单效蒸发
1.10液膜控制
2简述题（任选5题，每题10分，计50分）
2.1层流与湍流的区别？
2.2离心泵的安装高度及其确定方法？
2.3气液传质的双膜理论？
2.4聚式流态化的特点？
2.5吸收过程的基本理论？
2.6 过滤介质的特点？
3计算题（任选4题，每题15分，计60分）
3．1 在φ45×3mm的管路上装一文丘里管，文丘里管的上游接一压强表，其读数为137.5kPa，管内水的流速u1=1.3m/s，文丘里管的喉径为10mm，文丘里喉径部接一内径为3mm玻璃管，玻璃管下端插入水中，池内水面到管中心线的垂直距离为3m。

如将水视为理想流体，试判断池内中的水能否被吸入管中。

3.1题示意图
3.2在实验室内用一片过滤面积为0.05㎡的滤叶在36kPa的绝压下进行实验（大气压为101kPa）。

于300s内共吸出400cm3的滤液，再过600s，又过滤出400cm3滤液。

（a）估算该过滤压力下的过滤常数K。

（b）估算再收集400 cm3滤液需要再用多少时间。

3.3某板框过滤机于进行恒压过滤1小时之后，共送出滤液11m3，停止过滤后用3 m3清水（其粘度与滤液相等）于同样压力下对滤饼进行横穿洗涤。

求洗涤时间，假设滤布阻力可以忽略。

3.4两无限大平行平面进行辐射传热，已知ε1=0.3，ε2=0.8，若在两平行面间放置一无限大遮光板（ε3=0.2），试计算传热量减少的百分数。

3.5 在一个填料吸收塔中，用清水吸收含有溶质A的气体混合物，两相逆流操作。

进塔气体初始浓度为3%（A体积%），在操作条件下相平衡关系为Y=1.75X，试分别计算液气比为4和2时出塔气体的极限浓度和液体出口浓度。

3.6 在填料塔内用稀硫酸吸收空气中的氨。

当溶液中存在游离酸时，氨的平衡分压为
零。

下列三种情况下的操作条件基本相同，试求所需填料高度的比例：
（1）混合气含氨1%，要求吸收率为90%；
（2）混合气含氨1%，要求吸收率为99%；
（3）混合气含氨5%，要求吸收率为99%；
对上述低气体，吸收率可按η=（y a - y b）/y b计算。