硕士研究生入学考试试题.doc
全国硕士研究生入学考试政治试题及答案
全国硕士研究生入学考试政治试题及答案考试科目：政治考试时间：120分钟试题总分：150分考试类型：选择题、判断题第一部分：选择题（共100分）请根据题意选择最佳答案，并将其填写在答题卡上。
1. 下列哪个是中国共产党的最高纲领？A. 马克思主义基本原理B. 发展生产力C. 建设中国特色社会主义D. 党的总路线2. 全面建设社会主义现代化国家的目标是在什么基础上实现的？A. 全体人民自力更生B. 中国特色社会主义制度C. 民主政治制度D. 公有制经济3. 社会主义初级阶段的基本经济制度是什么？A. 公有制经济为主体B. 混合所有制经济C. 计划经济D. 市场经济4. 我国国家机关的性质是什么？A. 人民的工具B. 人民的服务者C. 资本主义D. 官僚主义5. 阶级斗争是马克思主义的核心观点之一，它的根本目的是什么？A. 保持社会稳定B. 实现社会平等C. 推动社会发展D. 实现无阶级社会......第二部分：判断题（共50分）请根据题意选择“正确”或“错误”，并将其填写在答题卡上。
1. 中国特色社会主义必须坚持党的领导，坚持以人为本，坚持经济持续发展，坚持改革开放，坚持科学发展观。
（）2. 中国共产党是中国工人阶级的先锋队，同时也是中国一切劳动者的先锋队。
（）3. 我国国家机关的任务是为人民服务，为人民维权。
（）4. 政治素质是指一个人具备政治觉悟、政治能力和运用政治方法处理社会问题的能力。
（）5. 中国特色社会主义制度是我国的根本制度，不可动摇。
（）......答案解析：第一部分：选择题1. A2. B3. A4. B5. C......第二部分：判断题1. 正确2. 正确3. 正确4. 正确5. 正确......注意：以上答案仅供参考，具体以考试或教师要求为准。
希望以上考试题目及答案能够帮助您更好地准备全国硕士研究生入学考试政治科目。
祝您考试顺利！。
2023年硕士研究生统一入学考试自命题试题4
35.水平肌链由口轮匝肌、颊肌和翼内肌构成（ ）
36.下颌边缘运动代表了下颌、颞下颌关节及其韧带和咀嚼肌旳功能潜能。（ ）
37.在ICP时, 下颌位置都居于正中, 不偏左不偏右（ ）
38.颈鞘位于颈交感干旳后方浅面（ ）
39.根管为位于牙根内旳大部分髓腔, 一般一种牙根内不一定只有一种根管（ ）
全国硕士硕士统一入学考试自命题试题
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学科与专业名称: 口腔基础医学 口腔临床医学 口腔医学（专业学位）
考试科目代码与名称: 352 口腔综合
二、判断题（你认为对旳, 用T表达, 错误旳用F表达。共50小题, 每题1分, 共50分）
1.根管长度电测量法旳原理是根据牙周膜与口腔黏膜简朴电阻恒定为, 设计出第一代旳根测仪牙周膜旳电阻值为40微安（ ）
2.弯曲根管旳器械制备原则是尽量将根管扩直（ ）
3.牙根尖形成术实际上是活髓疗法, 牙根尖成形术是对死髓旳年轻恒牙旳治疗（ ）
12.简述拔牙创骨组织修复重建过程？
13.试述颞下颌关节基本构成和形态特性？
14.请解释三个基本颌位及其三者旳关系？
15.描述上颌骨旳三大支柱以及支架构造？
16.何为面部旳危险三角区及其临床意义？
17.口腔黏膜旳非角质形成细胞有哪些？ 各有什么功能？
18.从病理学和生物学角度鉴别多形性腺瘤和腺淋巴瘤？
22.三角挺重要提供旳力是楔力（ ）
23.颞深间隙感染最轻易并发骨髓炎（ ）
24.临床创口分为无菌创口、污染创口、感染创口（ ）
2023年安徽大学硕士研究生入学354汉语基础考试试题
2023年安徽大学硕士研究生入学354汉语基础考试试题业务课名称：354汉语基础考生须知：1.答案必须写在答题纸上，写在其他纸上无效。
2.答题时必须使用蓝、黑色墨水笔或圆珠笔做答，用其他答题不给分，不得使用涂改液。
一、填空题1.语言符号有能指和所指之分，其中符号中的概念对应()2.上海话中，老年人对“烟”和“衣”的读音分的很清楚，但年轻人已经不分这属于语言变体中的()变体3.语流中，“早早儿”中第二个“早”的声调变调为()4.指称有定指和不定指之分，其中“领导来了”中的领导属于()5.“狗”有“狗仗人势”的用法，属于词义构成中的()意义6.从词义演变的角度分析，"其臭如兰”到"臭鸡蛋”,词义概念()了7.《葬花词》中“尔今死去依收葬，未卜依身何日丧”的方言词汇属于()方言8.“弓长张”中的“弓长”属于字形中的()9.发布《现代汉语通用字表》属于四定中的()10.“轻”“重”是一对反义词，其中属于有标记的是()11.“春分”和“蛋白”属于主谓式的是()12.“家家有本难念的经”属于熟语中的()13.“香喷喷”属于()形容词14.“不”和“没”中常用来表达主观意愿的是()15.在“木头桌子”“宽阔的马路”中，定语属于限定性的是()16.“病”是名词兼()17.“他圆圆的画了一个圈”和“她胆怯地看着领导”状语指向宾语的是()18."天黑了"属于()谓语句19.从复句类型看，“昨晚下了雨，地上全湿了”属于()复句20.“他参加不了”“他不参加了”其中含有情况有了变化的是()二、简答题1.写出下列儿化韵的国际音标1)“一块儿”中的“块儿”2)“瓜子儿”中的“子儿”2.加拼音我下午坐飞机回合肥3.改正下列词语中的错别字一张一弛声名雀起三、文言文阅读题1.请为() 中的古文加注标点(淳于晃者齐之赘婿也长不满七尺滑稽多辨数使诸候未尝屈辱齐威王之时喜隐好为淫乐长夜之饮沈湎不治) 委政卿大夫百官荒乱诸候并侵国且危亡在於旦暮左右莫敢谏淳于影说之以隐曰国中有大鸟止王之庭三年不蜚: 通“飞”)又不鸣王知此乌何也王日此鸟不蜚则已一蜚冲天不鸣则已一鸣惊人於是乃朝诸县令长七十二人赏一人诛一人奋兵而出诸侯振惊皆还齐侵地威行三十六年2. 根据这段古文填空1)“辨”的意思是2)“数”的意思是3)“旦”的意思是4)“以”的意思是5)“己”的意思是6)“还”的意思是四、辨析下列词语1.“据说”和“听说2.“对于”和“关于五、修改下列病句并说明理由1.既看不出他们有什么高明的知识，又看不出他们有丰富细致的感情2.生产衬衫有两道关键工序，一是上袖口，二是上领子。
中南财经政法大学硕士研究生入学考试法制史真题
2002年卷一：中国法制史学100分一、填空题（共20空，每空0 .5分，共10分。
）1、我国封建社会的五刑是--2、《法经》的编纂者是--3、唐朝的法律形式有--四种4、隋唐至明清中央三大司法机关是--5、《通制条格》是--朝的法律。
6、朱元璋为惩治贪官污吏，特意颁布了一部特别刑事法规，共四篇，史称《》。
7、明清时期，大理寺、刑部的职能发生了变化。
刑部负责--，大理寺负责--。
8、清末变法修律活动中，清廷颁布的第一部宪法性文件是《》。
9、近代中国第一部资产阶级宪法是--，它首次规定国家权力属于我国国民。
10、北齐律规定了十种严重罪行须受重惩，称为--。
二、标点下段古文，译成白话，并简述其法律思想要点。
（20分）其有情恣庸愚识沈愆戾大则乱其区宇小则睽其品式不立制度则未之前闻故曰以刑止刑以杀止杀刑罚不可驰于国笞捶不得废与家……德礼为政教之本刑罚政教之用犹昏晓阳秋相须而成者也[注：沈，通沉；愆：罪过；戾：暴戾；睽：违背]三、名词解释（每题5分，共50分）1、明德慎刑2、云梦秦简3、六礼4、亲亲得相首匿5、十恶6、张杜律7、鞫谳分司制8、宋慈9、沈家本10、马锡五审判方式四、简述题（20分，任选一题即可，两题都做不加分）1、简述唐宋两代法律中关于法官责任和审判回避的主要规定。
2、与中华法系的有关传统比较，试述我国诉讼制及司法制度在清末法制变革中发生的主要变革。
卷二：法理学一、辨析下列各组名词。
（每组5分，共25分）法律规则与法律原则法的效力与法的实效法的继承与法的移植法的规范作用与法的社会作用地方性法规与自治法规二、试述法制现代化及其基本特征（20分三、试述法对利益调整的方式方法（20分四、试述法律传统及其社会价值（20分）五、试述在我国法制建设中应坚持的法的评价标准。
（15分）卷三、综合课（中国法律思想史学40分）一、填空题（每空0.5分，共5分）1、战国时期的法家思想中，在"法"、"术"、"势"三种治国手段上，商鞅尤重于"法"，--侧重于"术"，--偏重于"势头"。
全国硕士学位研究生入学统一考试英语试题1-4答案
medals would be a pie in the sky. What’s more, the
international exchanges has brought about the growth of
Li Ming
(126 words)
52. 参考范文
As is vividly betrayed in the chart above, the number of gold
medals which are snatched by P.R. China has been climbing and
growth of Chinese sports. The Opening-up and Reform since 1978
has improved the development of economy in China, which has
laid a solid foundation for the development of sports in
university to make contribution to the development of my
hometown, which is still one of the ten counties in poverty.
Best wishes to you!
Sincerely Yours
Section Ⅰ Use of English
1. B
2. B
3. C
4. D
5. C
硕士研究生入学考试生物化学试题及答案
硕士研究生入学考试生物化学试题（A）一、选择题（选择1个正确答案，每题1分，共15分。
）1. 下列叙述中哪一个是正确的？（）A.线粒体内膜对H+离子没有通透性。
B.线粒体内膜能由内向外通透H+离子。
C.线粒体内膜能由外向内通透H+离子。
D.线粒体内膜能自由通透H+离子。
2. 下列有关RNA聚合酶的陈述中，哪一种是正确的？（）A. 合成多核苷酸链时，RNA聚合酶作用于核苷二磷酸。
B. RNA聚合酶作用时，需要引物。
C. RNA聚合酶在多核苷酸链的3' 端加上核苷酸。
D. RNA聚合酶可以在DNA模板的两条链上同时分别合成RNA。
3. 纤维素分子的糖苷键是（）糖苷键。
A.α(1→ 4)B. α(1→ 6)C. β(1→ 4)D. β(1→ 6)4. 前列腺素是一种（）。
A. 环羟脂酸B. 寡聚糖C. 多肽激素D. 氨基酸5. 要把膜蛋白完整地从膜上溶解下来，可以用（）。
A. 蛋白酶B. 透明质酸酶C. 去污剂D. 糖苷酶6. 形成蛋白质三级结构的驱动力是（）。
A. 离子键B. 疏水作用力C. 二硫键D. 氢键7. 真核生物mRNA的帽子结构中，m7G与多核苷酸链通过三个磷酸基连接，连接方式是（）。
A. 2ˊ-5ˊB. 3ˊ-5ˊC. 3ˊ-3ˊD. 5ˊ-5ˊ8. 在氧化脱羧反应中，需要下列哪一种辅酶？（）A. 磷酸吡哆醛B. 生物素C. 抗坏血酸D. 焦磷酸硫胺素9. 用下列方法测定蛋白质含量时，哪一种方法需要完整的肽键？（）A. 凯氏定氮法B. 紫外吸收法C. 茚三酮反应D. 双缩脲法10. 糖酵解的速度主要取决于（）的活性。
A. 磷酸葡萄糖变位酶B. 磷酸果糖激酶C. 醛缩酶D. 磷酸甘油激酶11. NADPH能为合成代谢提供还原势，NADPH中的氢主要来自（）。
A. 糖酵解B. 柠檬酸循环C. 氧化磷酸化D. 磷酸戊糖途径12. 生物体内甲基的直接供体是（）。
A. S-腺苷蛋氨酸B. 半胱氨酸C. 蛋氨酸D. 牛磺酸13. 酶催化反应中，决定酶促反应专一性的是（）。
2024年全国硕士研究生招生考试英语一真题考研英语一
2024年全国硕士研究生入学统一考试英语(一)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 the ANSWER SHEET.(10 points)There's nothing more welcoming than a door opening for you. 1 the need to be touched to open or close, automatic doors are essential in 2disabled access to buildings and helping provide general3to commercial buildings.Self-sliding doors began to emerge as a commercial product in 1960 after being invented six years4by Americans Dee Horton and Lew Hewitl. They5as a novelty feature, but as their use has grown, their 6 have extended within our technologically advanced world.Particularly7in busy locations or during times of emergency, the doors8crowdmanagement by reducing the obstacles put in people's way.9 making access both in and out of buildings easier for people, the difference in the way many of these doors open helps reduce the total area10 by them. Automatic doors often open to the side, with the panels sliding across one another. Replacing swing doors, these 11 smaller buildings to maximise the usable space inside without having to12 the way for a large, sticking-out door. There are many different types of automatic door, with each13 specific signals to tell them when to open.14 these methods differ, the main15 remain the same.Each automatic door system 16 the light, sound weight or movement in their vicinity as a signal to open. Sensor types are chosen to 17 the different environments they are needed in.18,a busy street might not19 a motion-sensored door, as it would constantly be opening for passers-by. A pressure sensitive mat would be more20 to limit the surveyed area.1.[A]Through [B]Despite [C]Besides [D]Without2.[A]revealing [B]demanding [C]improving[D]tracing3.[A]experience [B]convenience[C]guidance [D]reference4.[A]previously[B]temporarily [C]successively [D]eventually5.[A]held on [B]started out[C]settled down [D]went by6.[A]relations [B]volumes [C]benefits[D]sources7.[A]useful[B]simple [C]flexible [D]stable8.[A]call for [B]yield to [C]insist on [D]act as9.[A]As well as[B]In terms of [C]Thanks to [D]Rather than10.[A]connected[B]shared [C]represented [D]occupied11.[A]allow[B]expect [C]require [D]direct12.[A]adopt [B]lead [C]clear[D]change13.[A]adapting te [B]deriving from [C]relying on[D]pointing at14.[A]Once [B]Since [C]Unless [D]Although15.[A]records [B]positions [C]principles[D]reasons16.[A]controls [B]analyses[C]produces [D]mixes17.[A]decorate [B]compare [C]protect [D]complement18.[A]In conclusion [B]By contrast [C]For example[D]Above all19.[A]identify [B]suit[C]secure [D]include20.[A]appropriate[B]obvious [C]impressive [D]delicateSection 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 the ANSWER SHEET.(40 points)Text 1Nearly 2000 years ago, as the Romans began to pull out of Scotland, they left behind a curious treasure:10 tons of nails, nearly a million of the things. The nail hoard was discovered in 1960 in a four-metre-deep pit covered by two metres of gravel.Why had the Romans bunied a million nails? The likely explanation is that the withdrawal was rushed, and they didn't want the local Caledonians getting their hands on 10 tons of weapon-grade iron. The Romans buried the nails so deep that they would not be discovered for almost two millennia.Later civilisations would value the skilled blacksmith's labour in a nail even more than the raw material. As Roma Agrawal explains in her new delightful book Nuts and Bolts, early 17th-century Virginians would sometimes bum down their homes if they were planning to relocate. This was an attempt to recover the valuable nails, which could be reused after sifting the ashes. The idea that one might bum down an entire house just to reclaim the nails underlines how scarce, costly and valuable the simple-seeming technology was.The price of nails fell by 90%between the late 1700s and mid-1900s,as economist Daniel Sichel points out in a research paper. According to Sichel, although the falling price of nails was driven partly by cheaper iron and cheaper energy, most of the credit goes to nail manufactures who simply found more efficient ways to turn steel into nails.Nails themselves have changed over the years, but Sichel studied them because they haven't changed much. Roman lamps and Roman chariots are very different from LED strips and sports cars,but Roman nails are still clearly nails. It would be absurd to try to track the changing price of sports cars since 1695,but to ask the same question of nails makes perfect sense.I make no apology for being obsessed by a particular feature of these objects: their price. I am an economist, after all. After writing two books about the history of inventions, one thing Ive leamt is that while it is the enchantingly sophisticated technologies that get all the hype, it's thecheap technologies that change the world.The Gutenberg printing press transformed civilisation not by changing the nature of writing but by changing its cost-and it would have achieved little without a parallel collapse in the price of surfaces to write on, thanks to an often-overlooked technology called paper. Solar panels had few niche uses until they became cheap; now they are transforming the global energy system.21.The Romans buried the nails probably for the sake of[A]saving them for future use[B]keeping them from rusting[C]letting them grow in value[D]hiding them from the locals22.The example of early 17th-century Virginians is used to[A]highlight the thriftiness of early American colonists[B]illustrate the high status of blacksmiths in that period[C]contrast the attitudes of different civilisations toward nails[D]show the preciousness of nail-making technology at that time23.What played the major role in lowering the price of nails after the late 1700s?[A]Increased productivity.[B]Wider use of new energies.[C]Fiercer market competition.[D]Reduced cost of raw materials.24.It can be leamed from Paragraph 5 that nails[A]have undergone many technological improvements[B]have remained basically the same since Roman times[C]are less studied than other everyday products[D]are one of the world's most significant inventions25.Which of the following best summarises the last two paragraphs?[A]Cheap technologies bring about revolutionary change.[B]Technological innovation is integral to economic success.[C]Technology defines people's understanding of the world.[D]Sophisticated technologies develop from small inventions.Text 2Parenting tips obtained from hunter-gatherers in Africa may be the key to bringing up more contented children, researchers have suggested. The idea is based on studies of communities such as the Kung of Botswana, where each child is cared for by many adults. Kung children as young as four will help to look after younger ones and baby-wearing", in which infants are carried in slings, is considered the norm.According to Dr Nikhil Chaudhary, an evolutionary anthropologist at Cambridge University, these practices, Known as all oparenting, could lead to less anxiety for children and parents.Dr Annie Swanepoel, a child psychiatrist, believes that there are ways to incorporate them into western life. In Germany, one scheme has paired an old people's home with a nursery. The residents help to look after the children, an arrangement akin to alloparenting. Another measure could be encouraging friendships between children indifferent school years to miror the unsupervised mixed-age playgroups in hunter-gatherer communities.In a paper published in the Journal of Child Psychology and Psychiatry, researchers said that the western nuclear family was a recent invention which family broke with evolutionary history. This abrupt shift to an "intensive mothering narrative", which suggests that mothers should manage childcare alone, was likely to have been harmful. "Such narratives can lead to maternal exhaustion and have dangerous consequences, "they wrote.By contrast, in hunter-gatherer societies adults other than the parents can provide almost half of a child's care. One previous study looked at the Efe people of the Democratic Republic of Congo. It found that infants had an average of 14 alloparents a day by the time they were 18 weeks old and were passed between caregivers eight times an hour.Chaudhary said that parents now had less childcare support from family and social networks than during most of humans'evolutionary history,but introducing additional caregivers could reduce stress and maternal depression,which could have a“knock-on"benefit to a child's wellbeing.An infant bom to a hunter-gatherer society could have more than ten caregivers-this contrasts starkly to nursery settings in the UK where regulations call for a ratio of one carer to four children aged two to three.While hunter-gatherer children leamt from observation and imitation in mixed-age playgroups,researchers said that western"instructive teaching",where pupils are asked to sit still,may contribute to conditions such as attention deficit hyperactivity disorder.Chaudhary said that Britain should explore the possibility that older siblings helping their parents“might also enhance their own social development”26.According to the first two paragraph,alloparenting refers to the practice of[A]sharing child care among community members[B]assigning babies to specific adult caregivers[C]teaching parenting details to older children[D]carrying infants around by their parent27.The scheme in Germany is mentioned to illustrate[A]an attempt to facilitate intergenerational communication[B]an approach to integrating alloparenting into western culture[C]the conventional parenting style in western culture[D]the differences between western African ways ofliving28.According to Paragraph 4,the"intensive mothering narrative"_[A]alleviate parenting pressure[B]considerate family relationships[C]results in the child-centered family[D]departs from the course of evolution29.According to paragraph 6,what can we lean about nursery in the UK?[A]They tend to fall short of official requirements.[B]They have difficulty finding enough caregivers.[C]They ought to improve their carer-to-child ratio.[D]They should try to prevent parental depression.30.Which of the following would be the best title?[A]Instructive teaching:a dilemma for anxious parents[B]For a happier family,learn from the hunter-gatherers[C]Mix-aged playgroup,a better choice for lonely children[D]Tracing the history of parenting:from Africa to EuropeText 3Rutkowski is a Polish digital artist who uses classical painting styles to create dreamy fantasy landscapes.He has made illustrations for games such as Sony's Horizon Forbidden West,Ubisoft's Anno,Dungeons&Dragons,and Magic:The Gathering.And he's become a sudden hit in the new world of text-to-image AI generation.His distinctive style is now one of the most commonly used prompts in the new open-source AI art generator Stable Diffusion,which was launched late last month.The tool,along with other popular image-generation AI models,allows anyone to create impressive images based on text prompts.For example,type in"Wizard with sword and a glowing orb of magic fire fights a fierce dragon GregRutkowski,"and the system will produce something that looks not a milion miles away from works in Rutkowski's style.But these open-source programs are built by scraping images from the Internet,often without permission and proper attribution to artists.As a result,they are raising tricky questions about ethics and copyright.And artists like Rutkowski have had enough.According to the website Lexica,which tracks over 10 million images and prompts generated by Stable Diffusion,Rutkowski's name has been used as a prompt around 93,000 times.Some of the world's most famous artists,such as Michelangelo,Pablo Picasso,and Leonardo da Vinci,brought up around 2,000 prompts each or less.Rutkowski's name also features as a prompt thousands of times in the Discord of another text-to-image generator,Midjourney.Rutkowski was initially surprised but thought it might be a good way to reach new audiences.Then he tried searching for his name to see if a piece he had worked on had been published.The online search brought back work that had his name attached to it but wasn't his.“It's been just a month.What about in a year?I probably won't be able to find my work out there because[the internet]will be flooded with AI art,"Rutkowski says."That's concerning."“There is a coalition growing within artist industries to figure out how to tackle or mitigate this,"says Ortiz.The group is in its early days of mobilization,which could involve pushing for new policies or regulation.One suggestion is that AI models could be trained on images in the public domain,and AI companies could forge partnerships with museums and artists,Ortiz says.31.What can be leamed about Rutkowski from the first two paragraphs?[A]He is enthusiastic about AI generation painting.[B]He is popular with the users of an Al art generator.[C]He attracts admiration from other illustrators.[D]He specializes in classical painting digitalization.32.The problem with open-source AI art generators is that they[A]lack flexibility in responding to prompts[B]produce artworks in unpredictable styles[C]make unauthorized use of online images[D]collect user information without consent33.After searching online,Rutkowski found[A]a unique way to reach audiences[B]a new method to identify Al images[C]AI-generated work bearing his name[D]heated disputes regarding his copyright34.According to Ortiz,AI companies are advised to[A]campaign for new policies or regulations[B]offer their services to public institutions[C]strengthen their relationships with AI users[D]adopt a different strategy for Al model training35.What is the text mainly about?[A]Artists'responses to Al art generation.[B]AI's expanded role in artistic creation.[C]Privacy issues in the application of Al.[D]Opposing views on AI development.Text 4The miracle of the Chesapeake Bay lies not in its depths,but in the complexity of its natural construction,the interaction of fresh and saline water and the mix of land and water.The shallows provide homes for hundreds of species while storing floodwaters,filtering pollutants from water,and protecting nearby communities from potentially destructive storm surges.All this was put at great risk late last month,when the US Supreme Court issued a ruling in an Idaho case that provides the EPA far less authority to regulate wetlands and waterways.Specifically,a 5-4 majority decided that wetlands protected by the EPA under it Clean Water Act authority must have a“continuous surface connection”to bodies of water.This narrowing of the regulatory scope was a victory for builders,mining operators and other commercial interests often at odds with environmental rules.And it carries"significant repercussions for water quality and flood control throughout the US,"as Justice Brett Kavanaugh observed.In Maryland,the good news is that there are many state laws in place that provide wetlands protections.But that's a very shortsighted view,particularly when it comes to the Chesapeake Bay.The reality is that water and the pollutants that so often come with it,don't respect state boundaries.The Chesapeake draws from a 64000-square-mile watershed that extends to Virginia,Pennsylvania,New York,West Virginia,the District of Columbia and Delaware.Will thosejurisdictions extend the same protections now denied under Sackett V.EPA?Perhaps some,but all?That seems unlikely.It is too easy,and misleading,to see such court rulings as merely standing up for the rights of land owners when the consequences can be so dire for their neighbors.And it's reminder that they EPA's involvement in the Chesapeake Bay program has long been crucial as the means to transcend the influence of deep-pocketed special interests in neighboring states.Pennsylvania farmers,to use one telling example,aren't thinking about next year's blue crab harvest in Maryland when they decide whether to spread animal waste on their fields,yet the runoff into nearby creeks can have enormous impacts downstream.And so we would also call on state lawmakers from Richmond to Albany to consider reviewing their own wetlands protections and see for themselves the enormous stakes involved.We can't offer them a trip to the Chesapeake Bay model.It's been gone since the 1980s but perhaps a visit to Blackwater National Wildlife Refuge in Dorchester County where American bald eagles fly over tidal marshes so shallow you could not paddle a boat across them but teaming with aquatic life.It's worth the scenic drive.36.The Chesapeake Bay is described in Paragraph 1 as[A]a value natural environment[B]a controversial conservation area[C]a place with commercial potential[D]a headache for nearby communities37.The U.S.Supreme Court's ruling in the Idaho case[A]reinforces water pollution control[B]weakens the EPA's regulatory power[C]will end conflicts among local residents[D]may face opposition from mining operators38.How does the author feel about the future of the Chesapeake Bay?[A]Worried.[B]Puzzled.[C]Relieved[D]Encouraged.39.What can be inferred about the EPA's involvement in the Chesapeake BayProgram?[A]It has restored the balance among neighboring jurisdictions.[B]It has triggered a radical reform in commercial fisheries.[C]It has set a fine example of respecting state authorities.[D]It has ensured the coordination of protection efforts.40.The author holds that the state lawmakers should[A]be cautious about the influence of landowners[B]attach due importance to wetlands protections[C]recognize the need to expand wildlife refugesPart BDirections:Read the following comments on a report about American museums returning artifacts to their countries of origin and a list of statements summarizing the comments.Choose the best statement from the list A-G for each numbered name(41—45).There are two extra choices which you do not need to use.Mark your answers on the ANSWER SHEET.(10 points)(41)HannabSimply,there are people in Nigeria who cannot travel to the Smithsonian Institution to see that part of their history and culture represented by the Benin Bronzes.These should be available to them as part of their cultural heritage and history and as a source of national pride.There is no good reason that these artifacts should be beyond the ordinary reach of the educational objectives or inspiration of the generations to which they were left.They serve no purpose in a museum in the United States or elsewhere except as curious objects.They cannot be compared to works of art produced for sale which can be passed from hand to hand and place to place by purchase.(42)BuckWe know very exact reproductions of artwork can be and are regularly produced.Perhaps museums and governments might explore some role for the use of nearly exact reproductions as a means of resolving issues relating to returning works of art and antiquities.The context of any exhibit is more important to me than whether the object being displayed is 2,000 years old or 2 months old.In many cases the experts have a hard time agreeing on what is the real object and what is a forgery.Again,the story an exhibit is trying to tell is what matters.The monetary value of the objects on display is a distant second place in importance.(43)SaraWhen visiting the Baltimore Museum of Art,I came across a magnificentlSth-century Chinese sculpture.It inspired me to learm more about the culture that it represented.Artifacts in museums have the power to inspire,and perhaps spark that need to learn and understand the nature of their creators.Having said that,I do feel that whatever artifacts find their way to public museums should,in fact,be sanctioned as having been obtained on loan,legally purchased,or obtained by treaty.Stealing artifacts from other peoples'cultures is obscene;it robs not only the physical objects,but the dignity and spirit of their creators.(44)VictorAncient art that is displaced in foreign countries should be returned.…(缺失)(45)JuliaTo those of you in the comments section,by all means,who are having strong feeling about artifacts being removed from cities in the US and Britain,I would ask you to consider…(缺失)[A]It is clear that countries of origin have never been compensated for stolen artifacts.[B]It is a flawed line of reasoning to argue against returning artifacts to their countries of origin.[C]Museum visitor can still learn as much from artifacts copies after the originals are returmed.[D]Reproductions,even if perfectly made,cannot take the place of the authentic objects.[E]The real value of artifacts can only be recognized in their countries of origin rather than anywhere else[F]Ways to get artifacts from other countries must be decent and lawful.[G]Concern over security is no excuse for refusing to return artifacts to their countries of origin. 参考答案：41.E 42.C 43.F 44.G 45.BPart CDirections:Read the following text carefully and then translate the underlined segments into Chinese.Your translation should be written clearly on the ANSWER SHEET.(10 points)“Elephants never forget”—or so they say—and that piece of folklore seems to have some foundation.The African savanna elephant also known as the African bush elephant,is distributed across 37 African countries.(46)They sometimes travel more than sixty miles to find food or water,anc are very good at working out where other elephants are—even when they are out of ing tracking devices,researchers have shown that they have"remarkable spatial acuity",when finding their way to waterholes,they headed off in exactly the right direction,on one occasion from a distance of roughly thirty miles.What is more,they almost always seem to choose the nearest water hole.(47)The researchers are convinced that the elephants always know precisely where they are in relation to all the resources they need,and can therefore take shortcuts,as well as following familiar routes.Although the cues used by African elephants for long-distance navigation are not yet understood,smell may well play a part.Elephants are very choosy eaters,but until recently litle was known about how they selected their food.(48)One possibility was that they merely used their eyes and tried out the plants they found,but that would probably result in a lot of wasted time and energy,not least because their eyesight is actually not very good.(49)The volatile chemicals produced by plants can be carried a long way,and they are very characteristic:Each plant or tree has its own particular odor signature.What is more,they can be detected even when they are not actually visible.New research suggests that smell is a crucial factor in guiding elephants—and probably other herbivores—to the best food resources.The researchers first established what kinds of plant the elephants preferred either to eat or avoid when foraging freely.They then set up a“food station”experiment,in which they gave elephants a series of choices based only on smell.(50)The experiment showed that elephants may well use smell to identify patches of trees that are good to eat,and secondly to assess the quality ofthe trees within each patch.Free-ranging elephants presumably also use this information to locate their preferred food.参考译文：(46)它们有时跋涉六十多英里寻找食物或水，并且非常善于寻找其他大象的位置——即使它们不在视线范围内。
西安电子科技大学硕士研究生入学考试试题(含答案)
也可利用不进位乘法或列表法计算。 11、已知 H ( s ) 的零极点分布图如下图所示，单位冲激响应 h(t ) 的初始值 h(0 ) = 2 ，则该 系统的系统函数 H (s) = 。
+
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解：由零极点分布图可写出
s →∞
H ( s) =
H 0 ( s − 2) ( s + 2) 2 + 4
对应原函数为
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e2 t ε (−t ) + e − t ε (t )
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5
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0 (a)
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、 f (t ) = cos t + cos(8t )
B
、 f (t ) = sin(2t ) + sin(4t )
2
、 f (t ) = sin(2t ) sin(4t ) D、 f (t ) = cos (4t ) 解：选 B。由系统的幅频特性和相频特性可知：若输入信号的频率均处于 ω = −5 ∼ 5 之间， 既不产生幅度失真又不产生相位失真。只有 B 满足这一条件。 d 6、信号 f (t ) = [e ε (t )] 的傅里叶变换 F ( jω ) 等于 dt
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西北工业大学2012年硕士研究生入学考试试题试题名称：材料科学基础（A卷）试题编号：832说明：所有答题一律写在答题纸上第页共页一、简答题（每题10分，共50分）1.请简述滑移和孪生变形的特点？2.什么是上坡扩散？哪些情况下会发生上坡扩散？扩散的驱动力是什么？3.在室温下，多数金属材料的塑性比陶瓷材料好很多，为什么？纯铜与纯铁这两种金属材料哪个塑性好？说明原因。
4.请总结并简要回答二元合金平衡结晶过程中，单相区、双相区和三相区中，相成分的变化规律。
5.合金产品在进行冷塑性变形时会发生强度、硬度升高的现象，为什么？如果合金需要进行较大的塑性变形才能完成变形成型，需要采用什么中间热处理的方法？而产品使用时又需要保持高的强度、硬度，又应如何热处理？二、作图计算题（每题15分，共60分）1、在Fe-Fe3C相图中有几种类型的渗碳体？分别描述这些渗碳体的形成条件，并绘制出平衡凝固条件下这些不同类型渗碳体的显微组织形貌。
2、在两个相互垂直的滑移面上各有一条刃型位错AB、XY，如图所示。
假设以下两种情况中，位错线XY在切应力作用下发生运动，运动方向如图中v所示，试问交割后两位错线的形状有何变化（画图表示）？在以下两种情况下分别会在每个位错上形成割阶还是扭折？新形成的割阶或扭折属于什么类型的位错？3、已知H原子半径r为0.0406nm，纯铝是fcc晶体，其原子半径R为0.143nm，请问H原子溶入Al时处于何种间隙位置？4、柱状试样，当固溶体合金（k0＞1）从左向右定向凝固。
凝固过程中假设，凝固速度快，固相不扩散、液相基本不混合，α/L（固/液）界面前沿液体中的实际温度梯度为正温度梯度。
由于α/L界面前沿液体存在成分过冷区，晶体易以树枝状结晶生长。
当合金从左向右定向凝固，达到稳态凝固区时，请分析并画出：①k0＞1相图；②α/L界面处固体、液体的溶质浓度分布图；③液体中成分过冷区图三、综合分析题（共40分）1、试用位错理论解释低碳钢的应变时效现象。
2、如图所示，在立方单晶体中有一个位错环ABCDA，其柏氏矢量b平行于z轴1）指出各段位错线是什么类型的位错。
2）各段位错线在外应力τ作用下将如何运动？请绘图表示西北工业大学2012年硕士研究生入学考试试题答案试题名称：材料科学基础试题编号：832说明：所有答题一律写在答题纸上第页共页四、简答题（每题10分，共50分）6.请简述滑移和孪生变形的特点？答：滑移变形特点：1）平移滑动：相对滑动的两部分位向关系不变2）滑移线与应力轴呈一定角度3）滑移不均匀性：滑移集中在某些晶面上4）滑移线先于滑移带出现：由滑移线构成滑移带5）特定晶面，特定晶向孪生变形特点：1) 部分晶体发生均匀切变2) 变形与未变形部分呈镜面对称关系，晶体位向发生变化3) 临界切分应力大4) 孪生对塑变贡献小于滑移5) 产生表面浮凸7.什么是上坡扩散？哪些情况下会发生上坡扩散？答：由低浓度处向高浓度处扩散的现象称为上坡扩散。
应力场作用、电场磁场作用、晶界内吸附作用和调幅分解反应等情况下可能发生上坡扩散。
扩散驱动力来自自由能下降，即化学位降低。
8.在室温下，一般情况金属材料的塑性比陶瓷材料好很多，为什么？纯铜与纯铁这两种金属材料哪个塑性好？说明原因。
答：金属材料的塑性比陶瓷材料好很多的原因：从键合角度考虑，金属材料主要是金属键合，无方向性，塑性好；陶瓷材料主要是离子键、共价键，共价键有方向性，塑性差。
离子键产生的静电作用力，限制了滑移进行，不利于变形。
铜为面心立方结构，铁为体心立方结构，两者滑移系均为12个，但面心立方的滑移系分布取向较体心立方匀衡，容易满足临界分切应力。
且面心立方滑移面的原子堆积密度比较大，因此滑移阻力较小。
因而铜的塑性好于铁。
9.请总结并简要回答二元合金平衡结晶过程中，单相区、双相区和三相区中，相成分的变化规律。
答：单相区：相成分为合金平均成分，不随温度变化；双相区：两相成分分别位于该相区的边界，并随温度沿相区边界变化；三相区：三相具有确定成分，不随结晶过程变化。
10.合金产品在进行冷塑性变形时会发生强度、硬度升高的现象，为什么？如果合金需要进行较大的塑性变形才能完成变形成型，需要采用什么中间热处理的方法？而产品使用时又需要保持高的强度、硬度，又应如何热处理？答：合金进行冷塑性变形时，位错大量増殖，位错运动发生交割、缠结等，使得位错运动受阻，同时溶质原子、各类界面与位错的交互作用也阻碍位错的运动。
因此发生应变硬化，使强度、硬度升高。
较大的塑性变形产生加工硬化（应变硬化），如果需要继续变形就要进行中间热处理，即再结晶退火，使塑性恢复到变形前的状态，零件可继续进行塑性变形。
如果产品需要保持高的强度、硬度，可在最终热处理时采用去应力退火，去除残余应力，保持零件较高的强度、硬度。
五、作图计算题（每题15分，共60分）1、在Fe-Fe3C相图中有几种类型的渗碳体？分别描述这些渗碳体的形成条件，并绘制出平衡凝固条件下这些不同类型渗碳体的显微组织形貌。
答：渗碳体包括：初生（一次）渗碳体、二次渗碳体、三次渗碳体、共晶渗碳体、共析渗碳体，共五种。
（1）初生（一次）渗碳体：含碳量大于4.3%的Fe-C合金在平衡凝固时从液相结晶出来的渗碳体，形貌为板条状。
（2）二次渗碳体：含碳量0.77～2.11%的Fe-C合金，在1148℃冷却到727℃过程中，从γ相中脱溶的渗碳体。
（3）三次渗碳体：含碳量小于0.0218%时，低于727℃，从α相脱溶析出的渗碳体。
（4）共晶渗碳体：含碳量2.11～6.69%的Fe-C合金，在1148℃发生共晶反应时形成的渗碳体。
（5）共析渗碳体：含碳量0.0218～6.69%的Fe-C合金，在727℃发生共析反应时生成的渗碳体。
各渗碳体形貌见教材相关部分。
2、在两个相互垂直的滑移面上各有一条刃型位错AB、XY，如图所示。
假设以下两种情况中，位错线XY在切应力作用下发生运动，运动方向如图中v所示，试问交割后两位错线的形状有何变化（画图表示）？在以下两种情况下分别会在每个位错上形成割阶还是扭折？新形成的割阶或扭折属于什么类型的位错？答：a图：①XY向下运动与AB交割，产生PP′小台阶，宽度为|b1|②PP′的柏氏矢量仍为b2③PP′⊥b2为刃型位错④PP′不在原滑移面上，为割阶⑤XY平行于b2，不形成台阶b图：①AB位错线上出现PP′平行于b2，宽度为|b1|②PP′的柏氏矢量仍为b2③PP′∥b2为螺型位错④PP′在原滑移面上，为扭折⑤XY位错线上出现QQ′平行于b1，宽度为|b2|⑥QQ′的柏氏矢量仍为b1⑦QQ′∥b1为螺型位错⑧ QQ′在原滑移面上，为扭折3、已知H 原子半径r 为0.0406nm ，纯铝是fcc 晶体，其原子半径R 为0.143nm ，请问H 原子溶入Al 时处于何种间隙位置？答：fcc 晶体的八面体间隙414.0=R r ，四面体间隙225.0=Rr 。
根据题意知284.0143.00406.0==Al H R r ，因此H 原子应处于八面体间隙。
4、柱状试样，当固溶体合金（k 0＞1）从左向右定向凝固，凝固过程中假设，凝固速度快，固相不扩散、液相基本不混合，α/L （固/液）界面前沿液体中的实际温度梯度为正温度梯度。
由于α/L 界面前沿液体存在成分过冷区，晶体易以树枝状结晶生长。
当合金从左向右定向凝固，达到稳态凝固区时，请分析并画出：① k 0＞1相图；② α/L 界面处固体、液体的溶质浓度分布图；③ 液体中成分过冷区图。
答：柱状试样从左向右定向凝固，在固相不扩散、液相基本不混合、k 0＞1的条件下，在凝固达到稳态凝固区时，α/L 界面前沿液体溶质浓度分布C L 如图a 所示。
由于α/L 界面前沿液体中溶质浓度从左向右逐渐升高（与k 0＜1情况不同），成分与相图对应如图b 。
α/L 界面前沿液体中从左向右熔点逐渐升高（与k 0＜1情况相同）构成T L 曲线，加之界面前沿液体中的实际温度梯度为正温度梯度Tn ，即形成了由T L 、T N 两曲线组成的成分过冷区见图c ，在凝固过程中晶体易以树枝状结晶生长。
六、 综合分析题（共40分）1、试用位错理论解释低碳钢的应变时效现象。
答：将退火低碳钢进行少量塑性变形后卸载，然后立即加载，屈服现象不再出现。
如果卸载后在室温下放置较长时间或加热到一定温度保温，屈服现象再次出现，而且低碳钢的强度及硬度升高，这种现象称为应变时效或机械时效。
机理：柯垂尔理论认为，卸载后立即重新加载，位错已经脱钉，因此不再出现屈服现象。
放置或加热后再加载，位错被重新定扎，因此会再次出现屈服现象。
位错増殖理论认为，卸载后立即重新加载，位错已经増殖，因此不再出现屈服现象。
放置或加热后再加载，发生了回复，位错发生重排和抵消，因此会再次出现屈服现象。
两种理论均有实验依据，目前一般同时采用两理论解释应变时效的产生原因。
2、如图所示，在立方单晶体中有一个位错环ABCDA，其柏氏矢量b平行于z轴3）指出各段位错线是什么类型的位错。
4）各段位错线在外应力τ作用下将如何运动？请绘图表示答：1）AB、BC、CD、DA段都是刃位错2）AB和CD不动；BC向上滑移，AD向下滑移，如图所示。
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