2011年攻读硕士学位研究生入学考试试卷
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09-11华南理工854微生物生化试题854 华南理工大学2009 年攻读硕士学位研究生入学考试试卷(请在答题纸上做答,试卷上做答无效,试后本卷必须与答题纸一同交回)科目名称:微生物生化(含工业微生物学、生物化学) 适用专业:生物化工,发酵工程,生物制药共3 页第1 页一、填空题(每个空1分,共35分)1.侵染寄主细胞后暂不引起细胞裂解的噬菌体称为()。
2. 芽孢是芽孢细菌的()器官。
3.某些酵母在繁殖过程中,芽体不脱落,并相连接成藕节状,形似菌丝称()。
4.根瘤菌可与()植物共生固氮。
5. 荚膜的主要化学成分有()和()等,常采用()方法进行荚膜染色。
6.微生物的培养基按用途通常分为基础培养基、完全培养基、()、()、()五大类。
7.Lipopolysaccharides(LPSs) contain both lipid and carbohydrate, and consist of three parts: (), (), and (). (此题要求英语做答)8.Genetic recombination occurs in eucaryotes through sexual reproduction. In bacteria, recombination occurs through the processes of (),(), and (). (此题要求英语做答) 9.The multiplication cycle of bacteriophages, like that of all viruses, can be divided into five distinct stages: (), (), biosynthesis of viral components, (), and (). (此题要求英语做答)10.TCA循环中,α-酮戊二酸脱氢酶催化的反应需要的辅因子有:NAD +、TPP 、()、()、()和()。
河海大学历年攻读硕士学位研究生入学考试试题Ddaaa aa 2河海大学2000年攻读硕士学位研究生入学考试试题名称:材料力学一、概念题1.图示梁的四种截面形状,固定剪力沿铅垂方向。
横截面上最大剪应力(或剪应力铅垂分量的最大值)的位置,有四种答案:(5分) (A )全部在中性轴处; (B )全部不在中性轴处;(C )a 和b 在中性轴处,c 和d 不在中性轴处; (D )a 和b 不在中性轴处,c 和d 在中性轴处。
正确答案是:2.直径为d 的圆柱放在直径为D=3d 、厚为t 的圆形基座上,地基对 基座的支反力均匀分布,圆柱承受轴向压力P ,则基座剪切面的剪 力Q= (5分)3.图示车轴,n--n 截面周边上任一点处交变应力中的=m axσ=min σ循环特征r= (5分) 4.定性画出图示等截面梁的挠曲线形状(5分))(a )(b )(dz胶缝)(a )(b2.已知胶的许用剪应力][τ是许用正应力][σ的一半,问 ɑ为何值时,胶缝处的剪应力和正应力同时达到各自的 许用应力。
(10分)3.图(a )、(b )表示同一材料的两个单元体。
材料的屈 服极限MPa s 275=σ。
试根据第三强度理论求两个单元 体同时进入屈服极限时的拉应力σ与剪应力τ的值。
若σ>τ。
(10分)4.图示拐轴位于水平面内,受铅垂荷载1P 和水平荷载2P 试按第四强度理论确定圆轴AB 的直径。
已知:,kN P 201=, kN P 102=,mm l 1501=,mm l 1402=,MPa 160][=σ。
(155.图示1、2杆截面均为方形,边长分别是a 和a/3。
已知l =5a ,两杆材料相同,弹性模量为E 。
设材料能采用欧拉公式的临界柔度为100,试求2杆失稳时均布荷载q 的临界值。
(15分)6.AB 梁支承在两悬臂梁的端点,有重Q 的物体自H 高处自由下落在AB 梁的中点,三根梁的长度和刚度EI 均相同,AB 梁的抗弯截面系数为W ,求AB 梁的最大动应力m ax d 。
西北大学计算机专硕研究生入学考试历年真题集团文件发布号:(9816-UATWW-MWUB-WUNN-INNUL-DQQTY-西北大学2015年招收攻读硕士学位研究生试题(回忆版) 科目名称:数据结构科目代码:851适用专业:计算机技术、软件工程共2页答案请答在答题纸上,答在本试题上的答案一律无效。
一、简答 [每小题6分,共30分]1、简述四类基本的数据逻辑关系,并用图表示。
2、简述数组、广义表属于线性表原因。
3、算法的定义及特性。
4、什么是平衡二叉排序树平衡因子的取值范围是什么5、简述稳定排序含义,给出两种稳定排序方法以及两种不稳定排序方法名称并证明。
二、分析与方法选择 [每小题10分,共30分]1、折半查找法对待查找的列表哪两个要求?答:必须采用顺序存储结构;必须按关键字大小有序排列。
2、分析快速排序的性能(最好情况、最坏情况)。
3、关于二叉树结点度数的计算。
(牢记二叉树的5条性质,会计算二叉树及K叉树相关的计算。
)三、构造结果 [每小题8分,共40分]1、已知一棵二叉树的前序序列及后序序列,给出其对应的二叉树。
备注:西大历年试卷都是给出前序序列、中序序列或者中序序列、后序序列,写出对应的二叉树,这种题型很好做,且结果给出的二叉树唯一。
但是2015年试题给出的是已知前序序列、后序序列,求对应的二叉树,这题我们平时几乎都没做过,但是其实也不难,往往给出前序序列、后序序列,构造的二叉树不是唯一的,但是这次考题设置的巧妙,最后给出的结果二叉树应该是唯一的。
这道题具体我也不记得了,反正有点难,我也花了很长时间最后才做出来的。
2、图的两种存储结构及表示、深度优先搜索遍历、广度优先搜索遍历、最小生成树的生成。
3、依次输入(26,30,15,10,28,19,18,22),构造二叉排序树,并计算等概率情况下的查找成功的平均查找长度。
4、画出10个元素的折半判定树,并计算等概率情况下查找成功的平均查找长度。
5、最小生成树生成的两种算法:普里姆算法、克鲁斯卡尔算法。
全日制攻读教育硕士专业学位入学考试大纲(考试指导性意见)(科目:教育综合)一、考查目标全日制攻读教育硕士专业学位入学考试教育综合科目考试内容包括教育学原理、中国教育史、外国教育史和教育心理学四门教育学科基础课程,要求考生系统掌握相关学科的基本知识、基础理论和基本方法,并能运用相关理论和方法分析、解决教育实际问题。
二、考试形式与试卷结构(一)试卷成绩及考试时间本试卷满分为150分,考试时间为180分钟。
(二)答题方式答题方式为闭卷、笔试。
(三)试卷内容结构各部分内容所占分值为:教育学原理约60分中国教育史约30分外国教育史约30分教育心理学约30分(四)试卷题型结构名词解释题:6小题,每小题5分,共30分简答题: 4小题,每小题10分,共40分分析论述题:4小题,每小题 20分,共80分三、考查范围教育学原理一、考查目标1、系统掌握教育学原理的基础知识、基本概念、基本理论和现代教育观念。
2、理解教学、德育、管理等教育活动的任务、过程、原则和方法。
3、能运用教育的基本理论和现代教育理念来分析和解决教育的现实问题。
二、考查内容一、教育学概述(一)教育学的对象和任务教育学的研究对象是教育现象和教育问题;教育学的任务是揭示教育规律,探讨教育价值观念和教育艺术,指导教育实践。
(二)教育学的产生和发展教育学的萌芽、教育学的独立、教育学的发展多样化、教育学的理论深化等阶段有代表性、有影响的教育家、教育著作、教育思想和教育理论。
二、教育的概念(一)教育的质的规定性教育是有目的地培养人的社会活动。
有目的地培养人,是教育这一社会现象与其他社会现象的根本区别,是教育的本质特点。
(二)教育的基本要素教育者、受教育者、教育中介系统等要素的涵义、地位和作用。
(三)教育的历史发展古代教育的特点;现代教育的特点。
(四)教育概念的界定广义教育;狭义教育。
三、教育与人的发展(一)人的发展概述人的发展涵义;人的发展特点;人的发展的规律性。
河海大学2011年攻读硕士学位研究生入学考试试题解析科目代码:____813______ 科目名称:___材料力学_____ 满分:__________ 注意:1、认真阅读答题纸上的注意事项;2、所以答案必须写在答题纸上,写在本试题纸或草稿纸上均无效;3、本试题纸须随答题纸一起装入试题袋中交回。
一、基础题(50分)1、直径为d 的圆轴如图所示,AB=BC=CD=L ,切变(剪切)弹性模量为G ,画扭矩图并求AC 段的扭转角。
(15分)解:θBC 所以,θ2、悬臂梁说明解:a. b. c. d.3、组合变形矩形截面杆,横截面上的轴为F N ,弯矩y M 和z M 满足以下哪种情况时(选择题) (答案写在答题纸上) ,横截面的中性轴不过截面形心。
该杆件发生(填空题)(答案写在答题纸上) 变形(简要写出解答过程或原因)。
(6分) (1)横截面上的内力F 0≠N ,y M 0≠,z M 0≠ (2)横截面上的内力F =0N ,y M 0≠,z M 0≠ (3)横截面上的内力F =0N ,y M 0≠,z M 0≠ (4)横截面上的内力F =0N ,y M 0≠,z M 0≠解:F =0N ,y M 0≠,z M 0≠,弯曲变形4、总高度、材料均相同的圆截面柱子(柱子的自重不计),其中直径为D 部分的高度都相同,受到自由下落物体的竖向冲击,冲击五重为W ,试根据动荷系数,比较各杆的最大动应力dmax σ (排序)(简要写出解答过程或原因)。
(6分)解:d k 因为σ所以4σ5ν,求与轴线成45°解:x σ 4545-451=()εσνσ︒︒︒-E ,代入上述数据得 245=(1)d ενπ︒-FE 二、 综合题(共100分)1、图示槽形截面梁,已知:L=2m ,若材料的许用拉应力[]t =30a σMP ,许用压应力[]c =90a σMP ,对中性轴的惯性矩74z I =5.4910mm *,(1)画出弯矩图,(2)是根据正应力强度求梁的容许荷载[q]。
2013年河海大学全国研究生招生考试870管理学试题(整理版)一、名词解释以及解答(8*8=64分)1、公平理论2、管理创新3、法约尔的纪律原则4、管理方格理论5、波士顿矩阵6、人际关系学说7、管理的社会属性8、控制的原理二、阅读理解(16分)中国常用“领导”一词,许多人以身为领导为荣,许多人在为成为领导而努力,但是国外直接叫头衔,如某总,某经理,或者直接在名片上印有“协调人”字样,甚至什么都省了,直接叫名字,如“hi!Mike.”请问为何有这些差异?你会如何对待这种差异?三、案例分析(30分)主要讲的是稻盛和夫的“敬天爱人”管理哲学思想以及拯救日航(主营日本航空运输业),其中有涉及到他到海尔公司的参观。
【可以百度】问题:对“敬天爱人”的理解,结合海尔或其他企业的案例。
分析“敬天爱人”在拯救日航过程中如何发挥作用。
举例说明如何运用“敬天爱人”解决企业中的管理问题。
四、论述题(20*2=40分)1、毛泽东“管理也就是社会主义教育”和德鲁克“管理是一种以绩效责任为基础的专业职能”分析各自的内涵以及对两句话的比较分析。
2、如何管理企业文化。
2012年河海大学870管理学考研试题一,名词解释和简答(每小题7分,7*10=70)1、管理活动的基本职能2、决策的分类3、社会责任4、组织设计的扁平型结构5、期望理论6、创新职能的内容7、网络计划技术的内容8、沟通以及沟通的过程9、组织变革10、预算控制二、阅读理解(25)材料:管理创新需要充足的知识资源......问题是我们如何对待西方现代管理文化,你是否同意文中观点,说明理由。
用宽容的态度对待西方管理知识,对待古今中外一切管理知识三、案例分析(25)谷歌公司成功的经验材料是关于谷歌公司从创立到发展的过程,问题是分析谷歌快速发展的原因,并简单说明未来谷歌快速发展的方向(思路)四、论述题(30)举个例子,把管理学知识运用到学习、工作或生活中,使学习、工作或生活变的更轻松,更有效率河海大学2011年攻读硕士学位研究生入学考试试题(回忆版)一、名词解释与解答(每题满分8分,共64分)1、概念技能2、企业的社会责任3、扁平组织结构4、法约尔的统一命令原则5、阐述编制计划的步骤6、麦格雷戈X理论的主要观点7、控制的基本环节8、孔次管理定义二、阅读理解(满分16分)关于原则与原理的区别并举例说明(阅读材料和2001年真题一模一样,但问题有区别)一段材料,考查管理原理与管理原则的联系与区别。
目 录2012年河北工业大学825工程光学基础(I)考研真题2011年河北工业大学825工程光学基础考研真题2010年河北工业大学824工程光学基础考研真题2009年河北工业大学824工程光学基础考研真题2008年河北工业大学824工程光学基础考研真题2007年河北工业大学408工程光学基础考研真题2012年河北工业大学825工程光学基础(I)考研真题河3口2业大学2012年攻读硕士学位研究生入学考试试题[a]卷科目名称工程光学细{⑴科目代码B25共2恭适用专业'领域悦器科学与技术注:所有试题答案一律写在答题纸上.答案舄在试巍草稿纸上一律无她―、堵婿(共1S分,共5空,每空3分.答案T1*写在答题纸上.否则尤致.)1、椰寸于整个光涝系统而言,出射充瞄利___是共轴关系。
2、十人的远点此为眼JR0.5米.则这个人为反常眼中的,其时制S3眼统的度数为__*3、一个凸面健的半径为I加,剿怕的硼长度为_*4、巳制-块平如平板射归度为15烦,产生抽像移△〃=$;:用,则该平行平极的折射■率为.二、简答路简要W魂曲及证明题供84分,共14J®,每嫁6分*答案一够在谷题猊匕否则制奴)】、筒述全反射的定义,并给止厕个成用全反射的例f*2、人的K汕边观察水底的物体.感觉物惊比实际位置潦述是浅?说明理此3、分划给出理想光竽系统的勃IL放大率、铀时放大率点角放大亳的定义,并说明三曷之何的关系.4、祝域用昆微链的孑出光胡选在何她说明原琦并解释那ff的I作原m5'光学景湄姓如何忠义的?说明景深与榭对孔*汶「HJ的美系(假设堵距为定值〉.氏什么是迁续一次像,说明连鲤一粕象蚓物之间的坐标系关系.L什么始黄鸟原理,用更%原理征明光的由线传播定律.&、证明平而反射镀成完着像。
9、简述棱镜在光学系统中的作用。
10.忏女是鼓镜的汕J僦同知井荷述其作用.!|、反射定律为t=-r.耳中,为入肘:f t,-1"为反射仙,说明反射角为什么为负.也、证明平行平扳佝.三个成大军a、§、/均为L骂、一f光学系绍f-个像方麹距为lOOuini,门径为Mem的道镜,-个口符为1如的光孔,位于-透辎ti-边如血=匪,对无穷远姓的物制成像,求这个系统泡相对孔帝.14.说明炀镜在光学系统中的作用.三、作图求雌〈共11分,第一愚5分,第二翻6分.答案一律写在答题舐上否则无漱.)L在下图理想光哮春统中,尸为物泌林玲为像方域点,[为物方主点,H’为像方*瓶.求物点橹过理堂事£,学系统后所成的像4,(将下图光通在苔期瓠!-.然后在答峻flj上血出答案工A2、由给淀的物方擘标系,判断下面光学系统中慢方坐嫁系(但画出最后的橡方坐标系仰可),四、*獭(共40分,共4题,每题10分,答案一律写在答题心I舌则无效.〉1、f折射厥肮晚ffi左辿的指射率为L球曲右通的折射率为1.5,物体位于顶点左沾100m处,像镣『顶点右边1就w®甄求球面的半径,判断球面是凹面还是凸面并说明理总求醐放大率、轴向放大率及角放大率-分)M有一正透镜对某一^成倒立的安伽像制与物高相等。
厦门大学2011年招收攻读硕士学位研究生入学考试试题科目代码:832科目名称:生物化学考生须知:答案必须使用墨(蓝)色墨水(圆珠)笔;不得在试卷(草稿)纸上作答;凡未按规定作答均不予评阅、判分一、填空题(每空1分,共30分)1.在核酸中占9%-11%,且可用来计算核酸含量的是()。
2.用DNFB与Ala-Gly反应后,再用6mol/l的盐酸在110度下水解,所得产物是()和()。
3.酶的共价修饰调节中,最常见的调节方式是()负责催化该修饰方式的酶是()。
4.当酶促反应速度V达到最大反应速度的80%时,底物浓度为()。
5.糖的氧化分解、糖异生、和糖原合成的交叉点是()。
6.纤维素中的葡萄糖连接方式是(),直链淀粉中葡萄糖的连接方式是()。
7.用NaOH处理1-软脂酰-2-油酰磷脂酰丝氨酸得到的产物是(),(),()和甘油和丝氨酸。
8.在PH6-8是有缓冲能力的是(),而水溶液没有旋光的氨基酸是()。
9.引起蛋白质折叠的主要动力是()。
10.蛋白质通过Sephadex柱时,蛋白质从柱上洗脱的顺序是()。
11. TCA循环中不以NAD为辅酶的酶是()。
12.丙二酸对琥珀酸脱氢酶的抑制作用属于典型的()抑制。
13.生物素是()的辅基,在合成作用中起活性CO2的作用。
14.糖原在糖原磷酸化酶催化下从()端磷酸解。
15.脂肪酸在线粒体中的氧化称为().其特点是氧化从()开始,每氧化一次,减少一个二碳单位,生成一份子()。
16.直接参与糖原合成的三磷酸核苷是(),直接参与磷脂合成的三磷酸核苷是(),直接参与蛋白质合成肽链延长的三磷酸核苷是()。
17.尿素形成中,一个氮原子来自氮,另一个来自于()。
18.通过与DNA分子中的G-C顺序结合,阻止RNA聚合酶催化RNA 链延长的抗生素是()。
19.mRNA分子中密码子与氨基酰-tRNA中()配对。
20.脂肪酸生物合成中的限速反应是由()酶催化的反应。
二、选择题(单选每题1分,共30分)1. 不含糖苷键的化合物是()A.肝素B. 脑苷脂C. 半乳糖二脂酰甘油D. 胆固醇脂2. 哪个不是核苷酸()A. CoASHB. FADC. FH4 D . NADH3.葡萄糖有氧氧化过程中共有()A . 4次脱氢3次脱羧 B. 5次脱氢3次脱羧C. 6次脱氢2次脱羧 D. 6次脱氢3次脱羧4. 脂肪酸B-氧化中第一次脱氢反应受氢体是()A. NADB. FADC. NADPD. FMN5. 在糖、脂肪和蛋白质分解代谢中产生的CO2水、和ATP过程中都会有中间产物()A. 丙酮酸B. 氨基酸C. 乙酰-COAD. 甘油6. 含有疏水侧链氨基酸的是()A. 色氨酸、精氨酸B. 苯丙氨酸、异亮氨酸C. 精氨酸、亮氨酸D. 甲硫氨酸、组氨酸7. 糖酵解过程中哪种物质提供-P使ADP生成ATP()A. 3-磷酸甘油醛B. 2,3-而磷酸甘油醛C. 磷酸烯醇式丙酮酸D. 2-磷酸甘油酸8. 用重金属盐沉淀蛋白质时溶液PH应符合下列那个条件()A. 溶液的PH大于蛋白质的PI B . 溶液的PH小于蛋白质的PI C. 溶液的PH等于蛋白质的PI D. 溶液的PH等于7.49. 代谢调节最终是通过什么发挥作用的()A. 神经B. 激素C. 核酸D. 酶10.体内的CO2来自()A. 糖呼吸链中氧化还原 B . 脂肪酸的分解C. 糖原的分解D. 有机酸的脱羧11.蛋白质分子构想的结构单元是()A. 肽键 B . 二硫键 C. 肽键平面 D. 氨基酸残基12.丙二酸对琥珀酸脱氢酶的动力学特征是()A . Km上升Vmax不变B . Km下降Vmax不变C . Km不变Vmax上升D . Km上升Vmax不变13.那一种不属于二碳单位()A . COOH B. -CH3 C. =CH2 D. -CHO14.嘌呤环的N1来自于()A . NH3B . AspC . GlnD . Asn15.羧肽酶A对一小肽不起作用,此肽可能是()A. C-末端可能是碱性氨基酸B. Pro位于C-末端第二位C . 此肽为环状碱基修饰 D. 以上三种情况都可能16.若用电泳分离GLY-LYS、ASP-VAL 和ALA-HIS 在以下那个PH条件电泳最合适()A . PH 在2以下B . PH 2-4C . PH7-9 D. PH10-1217.氨基酸是通过下列哪种化学键与tRNA结合的()A. 糖苷键B. 酯键C. 酰胺键D. 氢键18. 从某种组织中提取一种酶,最理想的酶制剂是()A.蛋白质含量高B. 活力单位数最高C. 比活力最高D. Km最低19.当用C14标记乳酸的羧基碳原子时,并经受在细胞内的代谢转变.下列化合物除那种外都含有C14()A . a-酮戊二酸 B. 乙酰辅酶A C. 丙酮酸 D. 葡萄糖20. 反密码子IGC 可识别()A. GCA B . GCG C . ACG D. UCG21. DNA 连接酶在下列那一过程中不需要()A . DNA复制 B. 制备重组DNAC. DNA 修复 D . DNA断裂22.下列因素中能破坏蛋白质分子中二硫键的是()A. 处在8MOL/L的尿素溶液中B. 用水透析C. 加入二硫苏糖醇D. 蛋白质水解酶23.端粒酶是()A. 限制性内切酶 B . DNA聚合酶C . RNA聚合酶 D. 肽酰基转移酶24. m2Gs是()A. 含有2个甲吉的鸟嘌呤腺苷 B . 杂环上2位带有甲基的鸟苷C. 核糖2位带有甲基的鸟苷酸 D. 鸟漂亮核苷酸二甲脂25.性激素受体蛋白位于()A. 细胞核B. 细胞质膜C. 细胞质D. 微粒体26.如果一种化学修饰剂可以促进蛋白质的降解,则这种化学修饰剂可()A. 抑制蛋白质基因的表达B. 刺激蛋白质基因的表达C. 调节蛋白质基因的表达D. 与之无关27.当培养基中的色氨酸浓度较大时,色氨酸操纵子处于()A. 诱导表达B. 阻遏表达C. 基本表达D. 组成表达28.合成后无需进行转录后加工修饰就具有生物学活性的是()A . TRNA B. hnRNAC. 原核细胞MRNAD. 真核细胞MRNA29.下列几种酶,哪一个需要金属离子做辅基()A. 羧肽酶B. 核糖核酸酶C. 溶菌酶D. 胰凝乳蛋白酶30.八肽GLY-TYR-PRO-ARG-MET-ALA-PHE用那种方式处理不会产生任更小的肽()A. 溴化氢 B . 胰蛋白酶 C . 胰凝乳蛋白酶 D. 盐酸三、是非判断(每题1分,共20分)1.Edman降解法可以测定任何非封闭多肽的全部氨基酸序列。
南京财经大学2011年攻读硕士学位研究生入学考试(初试)试卷A考试科目:432统计学适用专业:应用统计硕士满分150分考试时间:2011年1月16日下午2:00——5:00注意事项:所有答案必须写在答题纸上,做在试卷或草稿纸上无效;请认真阅读答题纸上的注意事项,试题随答卷一起装入试题袋中交回。
注:答题过程中可能要用到的数据:u0.975=1.96,u0.95=1.65,t0.95(9)=1.833, t0.95(10)=1.812, t0.975(9)=2.262, t0.975(10)=2.228一、单项选择题(本题包括1-30题共30个小题,每小题1分,共30分。
在每小题给出的四个选项中,只有一个符合题目要求,把所选项前的字母填在答题纸相应的序号内)。
1.从含有N个元素的总体中,抽取n个元素作为样本,使得总体中的每一个元素都有相同的机会(概率)被抽中,这样的抽样方式称为()。
A.简单随机抽样B.分层抽样C.系统抽样D.整群抽样2.一家公司的人力资源部主管需要研究公司雇员的饮食习惯,改善公司餐厅的现状。
他将问卷发给就餐者,填上后再收上来。
他的收集数据的方法属于()。
A.自填式问卷调查B.面访式问卷调查C.实验调查D.观察式调查3.将全部变量值依次划分为若干个区间,并将这一区间的变量值作为一组,这样的分组方法称为()。
A.单变量值分组B.组距分组C.等距分组D.连续分组4.将某企业职工的月收入依次分为2000元以下、2000元-3000元、3000元-4000元、4000元-5000元。
5000元以上几个组。
第一组的组中值近似为()。
A.2000B.1000C.1500D.25005.经验法则表明,当一组数据对称分布时,在平均数加减1个标准差的范围内大约有()。
A.68%的数据B. 95%的数据C. 99%的数据D. 89%的数据6.在比较两组数据的离散程度时,不能直接比较它们的标准差,因为两组数据的()。
AGENERAL ENGLISH QUALIFYING TESTFOR NON-ENGLISH MAJOR GRADUATE STUDENTS(GETJun2511)PAPER ONEPART I LISTENING COMPREHENSION (25 minutes, 20 points)Section A ( 1 point each)1. A. Go shopping.B. Go car racing.C. Go to work.D. Go on a trip.2. A. Because she hasn‘t been on line lately.B. Because she has too much work to do.C. Because she is on a vacation.D. Because she has been busy typing.3. A. Go to an emergency exit.B. Enjoy herself in the park.C. Move her van right away.D. Try to find the road sign.4. A. A secretary.B. A salesperson.C. A tennis player.D. A receptionist.5. A. She deserves the promotion.B. She has to transfer to another job site.C. She‘ll pay for the dinner this time.D. She‘ll invite her parents over for a celebration.6. A. She should drop the biochemistry class.B. She should try harder.C. He prefers to learn rocket science.D. He can‘t understand it either.7. A. She totally dislikes it. B. She prefers the old one.C. It may lack practical value.D. It is much better than expected.8. A. 7: 00. B. 7: 30.C. 9: 00.D. 9:30.9. A. She was told about the trip beforehand.B. She was helped to pick up the beans.C. She was so excited that she revealed the news.D. She was not enthusiastic about the trip.Section B (1 point each)Directions:In this section you will hear two mini-talks. At the end of each talk, there will be some questions. Both the talks and the questions will be read to you only once. After eachquestion, there will be a pause. During the pause, you must choose the best answerfrom the four choices given by marking the corresponding letter with a single baracross the square brackets on your machine-scoring Answer Sheet.Mini-talk One10. A. High expectations.B. Excellence and value.C. Terror and violence.D. Strength and power.11. A. Attend a sleepover.B. Play a piece of music.C. Watch TV.D. Be in a school play.12. A. Her parenting methods are limited to Chinese families.B. She brought up her daughters with an extreme parenting method.C. Her daughters were given enough time to follow their own interests.D. She had low expectations of her children‘s abilities.Mini-talk Two13. A. 650 million dollars.B. 560 million dollars.C. 40 million dollars.D. 50 million dollars.14. A. Saint Paul.B. Chapel of Love.C. The Nickelodeon Universe.D. Underwater Adventures.15. A. Tasting the delicious food.B. Getting married.C. Visiting a campus.D. Seeing ocean animals.Section C (1 point each)Directions: In this section you will hear a short lecture. Listen to the recording and complete the notes about the lecture. You will hear the recording twice. After the recording you areasked to write down your answers on the Answer Sheet. You now have 25 seconds toread the notes below.(请在录音结束后把16-20题的答案抄写在答题纸上)16. The first tip on how to reduce your test stress is to use a little stress _______ (3 words).17. Good study (3 words) are important to learning effectively and doing well ontests.18. If you find yourself thinking negative thoughts, replace them with (2 words).19.Everyone makes mistakes. Learning to tolerate small ( 3 words) is a valuableskill.20. Taking care of your health can help keep your mind (4 words).PART II VOCABULARY (10 minutes, 10 points )Section A (0.5 point each)21. There used to be many guys who asserted themselves as all-powerful Chi Kung masters in China.A. conformedB. informedC. affirmedD. performed22. Children from an obscure family have to make greater efforts to climb the social ladder.A. unknownB. prominentC. controversialD. rural23. A permanent job plus a decent salary is what most of these young guys in China hope for.A. nobleB. adequateC. modestD. polite24. These transit workers went on strike in defiance of the relevant union policy.A. in line withB. in return forC. in response toD. in spite of25. This retired scientist takes on leadership roles with nearly every organization she is part of.A. assumesB. opposesC. pretendsD. desires26. Winslow Homer captured the look and spirit of American life with unparalleled eloquence.A. incredibleB. inevitableC. unmatchedD. unnoticed27. Many parents encounter occasions when their child doesn‘t turn in their homework assignments.A. participate inB. hand inC. engage inD. invest in28. The two elements of success that are intimately connected are creativity and innovation.A. familiarlyB. approximatelyC. looselyD. closely29. Jonathan Alter once said that admission of guilt tends to breed public sympathy.A. produceB. concealC. evadeD. combat30. Seawater near the Fukushima plant is showing elevated levels of radioactivity in Japan.A. stabilizedB. reducedC. increasedD. saturatedSection B (0.5 point each)31. The full impact of the recent tsunami caused by an earthquake in Japan is _______ to predict.A. unlikelyB. impossibleC. unableD. incapable32. A simple blood test may help identify those _______ high risk of dying from heart disease.A. inB. onC. atD. for33. Although US new home sales begin to _______ speed, the rate is still near historical lows.A. turn upB. pick upC. set upD. break up34. It was already dark _______ I got up from my seat and prepared to leave my office.A. by the timeB. since the timeC. until the timeD. during the time35. Health care providers wish to improve their _______ through regular continuing education.A. equivalenceB. competenceC. relevanceD. prevalence36. Auto makers should never _______the quality of products amid fierce competition.A. bring into playB. make sense ofC. lose sight ofD. end up with37. Mayor Pat Patterson said this new initiative _______ improving parking and pedestrian access.A. involvesB. evolvesC. dissolvesD. resolves38. Many of the foreign friends of the Chinese are _______ at the radical changes in China.A. dismayedB. amazedC. startledD. shocked39. These researchers intend to _______ this research until there is some substantial finding.A. insist onB. call onC. live onD. carry on40. Men and women of all ages can benefit from _______ amounts of daily physical exercise.A. considerateB. desperateC. moderateD. literatePART III CLOZE TEST (10 minutes, 10 points, 1 point each)What relationship is regarded as good for partners? There is no universal, ideal model ___41___ which a relationship can be evaluated. A ―good relationship‖ is one that works for both partners and effectively supports them in achieving their goals. If this is not working at some point, it does not ___42___ mean that the couple requires therapy. All relationships tend to encounter problems during ___43___ periods and at different stages, and many couples have a good ability ___44___ their difficulties without professional help. However, some may find that they are continually unhappy with their relationship. Sometimes one partner feels frustrated and misunderstood ___45___ his or her mate is totally unaware of the situation.If the couple are unable to resolve issues in a ___46___ that is acceptable to both partners, professional help should be considered. Many couples only consider therapy as a last ___47___. It may, however, be helpful at any time. ___48___, seeking therapy soon after things get ―stuck‖prevents a ___49___ of frustration and disappointment. The aim of couple therapy is not only to help the couple deal appropriately with immediate problems, but also to achieve better ways of relating ___50___.41. A. to B. against C. for D. at42. A. certainly B. definitely C. necessarily D. fundamentally43. A. fictional B. peaceful C. eventual D. stressful44. A. of solving B. to solving C. in solving D. to solve45. A. while B. so C. unless D. where46. A. respect B. manner C. method D. view47. A. resort B. creature C. meal D. beginning48. A. On the contrary B. On one hand C. For example D. First of all49. A. laptop B. jetlag C. takeoff D. buildup50. A. in detail B. in general C. in vain D. in forcePART IV READING COMPREHENSION (45 minutes, 30 points, 1 point each)Passage OneRemember Farid Seif? Mr Seif is the Houston Iranian-American businessman who mistakenly carried a Glock handgun through security, onto a plane, all the way from Houston to Indianapolis. When he got to his destination and realized his mistake, he alerted security officials. There was reportedly ―nothing else‖ in Mr Seif‘s carry-on besides the weapon. Yet the security screeners at George Bush International, America‘s eighth-busiest airport, missed it entirely. The scariest part of that story was that Transportation Security Administration officials told reporters that this type of incident was ―not uncommon.‖Now another Texas airport, Dallas-Fort Worth, is proving the point. This week, a high-level TSA source told the local NBC affiliate that ―An undercover TSA agent was able to get through security at Dallas/Fort Worth International Airport with a handgun during testing of the enhanced-imaging body scanners.‖The TSA insider who blew the whistle on the test also said that none of the TSA agents who failed to spot the gun on the scanned image were disciplined. The source said the agents continue to work the body scanners today.This is not confidence-inspiring. If TSA screeners can‘t even stop guns getting through security, why are they taking away our bottled water? Incidents like this only lend incentives to TSA critics who say the whole airport security apparatus is an enormous waste of time and money. The TSA‘s attitude towards the reporting of these sorts of messes isn‘t helpful, either. They only provided NBC with a brief statement claiming that they don‘t reveal the results of secret testing for ―security reasons‖and arguing that ―advanced imaging technology is an effective tool to detect both metallic and nonmetallic items hidden on passengers.‖ That‘s pretty much the public affairs equivalent of sticking their fingers in their ears and saying ―lalalalala we can‘t hear you!‖It is really hard to have an accountable TSA without greater transparency about the results ofsecret testing. Instead of leaking hints to the press that failure rates have decreased since the last public reports, the TSA should back up its whispering with actual data. If it won‘t, some enterprising congressional committee should order it. ―Trust us that this works‖ just isn‘t cutting it anymore.51. Mr. Seif‘s handgun ________.A. passed the check at the Houston airportB. caused big trouble for himself in HoustonC. was tracked down by officials in IndianapolisD. triggered a series of false alarms in Indianapolis52. What happened at Dallas-Fort Worth ________.A. helped rebuild public confidenceB. was merely an unusual accidentC. caused greater concern over securityD. resulted in unexpected disorder53. After the Dallas-Fort Worth report, TSA ________.A. reluctantly punished the relevant agentsB. allowed the relevant agents to stay in positionC. enhanced security check at relevant airportsD. began to reconsider relevant security methods54. The TSA‘s statement concerning the reported cases shows that they are ________.A. practicalB. uncooperativeC. reliableD. unpredictable55. What is the author‘s demand for TSA?A. No more secret testing.B. Promising to be responsible.C. Rapid response to emergency.D. Releasing results with evidence.56. The last sentence of the passage suggests that the author‘s attitude to the TSA is ________.A. appreciativeB. criticalC. tolerantD. indifferentPassage TwoOnce upon a time, staying a healthy weight was easy. To lose weight you simply had to practise the reverse of home economics—spend more than you earned. Unfortunately for many,but perhaps not surprisingly, it turns out that people are rather more complicated than bank accounts.To stay a healthy weight, you need a hormone called leptin to work properly. It sends ―I‘m full‖ messages from the fat cells up to the brain, where they go, among other places, to the same pleasure centers that respond to drugs like cocaine. Obese people produce plenty of leptin, but the brain doesn‘t seem to respond to it properly. Last year, researchers at the Oregon Research Institute scanned the brains of overweight people and found their reward circuits were underactive. They were eating more to try to get the enjoyment they were missing.There‘s a lot of evidence for the fact that most, if not all, of us have a set point around which our weight can vary by about seven to nine kilos, but anything beyond that is a real struggle. Making changes is hard, particularly if your body is working against you. So why not ditch the traditional approaches and try some new methods, based on the latest research, that work with your body rather than against it.Several years ago researchers at the National Institute on Aging in Baltimore reported that when they gave rats very little food one day and allowed them to eat plenty the next, they showed virtually all the benefits of a permanent calorie restriction diet. The same goes for humans, according to Dr James Johnson.How does it work? Besides forcing the body to burn fat, it may also trigger hormonal changes. Most people say that the diet takes a bit of getting used to, but is not as grinding as trying to cut back on an everyday basis.Older dieters may remember something called brown fat. Unlike the undesirable white stuff, this was a dieter‘s dream. Instead of storing excess energy as fat, brown-fat tissue burned it off to keep you warm—at least in mice. Brown fat fell out of favor because researchers couldn‘t find much in humans but now, thanks to the New England Journal of Medicine, it‘s back in fashion. The idea is to expose people to cold temperatures. They then make more brown fat and their weight drops.57. The last sentence in Paragraph 1 means that people‘s understanding of losing weight ________.A. seems rather unreasonableB. is unnecessarily complicatedC. used to be limitedD. can be partly justified58. According to the findings of the Oregon Research Institute, ________.A. overweight people get less pleasure from eating the same amountB. overweight people enjoy eating more than the others doC. people will become overweight if they eat more than they needD. people are more likely to be overweight if they produce less leptin59. The method used by the National Institute on Aging can be summarized as ―________‖.A. no diet at allB. diet on a daily basisC. diet every other dayD. diet permanently60. The word ―grinding‖ in the Paragraph 5 is closest in meaning to ________.A. effectiveB. realisticC. unreliableD. miserable61. It can be learned that brown fat ________.A. converts excess energy into fatB. works better in warm temperaturesC. burns extra energy to produce heatD. accumulates easily in human bodies62. The author‘s purpose in writing is to ________.A. compare the various ways of cutting caloriesB. recommend new methods of losing weightC. point out the misconceptions of losing weightD. clarify the common myth about weight lossPassage ThreeA study by Dr David Lewis from The University of Sussex, who coined the term ―road rage‖, found that motorists face a hidden mental health impact from the stresses of driving, while bus travel can produce long-term health benefits.For the experiment, the heart rate and EDR (Electro-Dermal Response) of 30 commuters was measured when taking similar journeys by car and bus. The findings reveal a vast difference in EDR, a form of biophysical measurement that indicates mental stress. The EDR results suggested that taking the car produced significantly more stress than taking the bus, which was 33% less stressful.―EDR can be a hidden stress - it‘s not as visible as intensely nervous driving or audible as road rage. This type of stress can have long-term physiological and emotional implications,‖ said Dr Lewis, who finds three key factors that increase the stresses of driving a car.Driving in heavy traffic - especially against a deadline - requires a high level of attention. This requires the brain to work especially hard processing a myriad of incoming information and making, often split-second, decisions.Congestion and delays can raise blood pressure and physical tension which may manifest itself as ‗road rage‘, having serious long-term health consequences and causing drivers sometimes to take reckless and foolish decisions. Driving in congested traffic now outweighs any previous benefits car-driving once gave.A sense of frustration of ‗wasting one‘s life‘behind the wheel of the car, unable to doanything more productive than casual conversations or listening to the radio. On a bus it is possible to fill the time more profitably by doing some work or reading.He also notes that highly trained, professional bus drivers are skilled in negotiating the challenges of the road, and the relief of trusting someone else to be in charge of the journey is a key part of what makes taking the bus less stressful.He encourages people to get out of their cars and on to the bus for trips where it makes sense - such as shopping in town or heading to a restaurant – so that you don‘t need to battle traffic or find parking. Switching simple journeys can help achieve the goal of taking a billion car journeys off the road. All it will take is everyone shifting around a trip a month.63. The finding of the study mentioned in this passage is that _______.A. cars cause more traffic accidents than busesB. driving a car is more stressful than taking a busC. high blood pressure is harmful to human healthD. car driving is accompanied by many distractions64. The term ―road rage‖ probably refers to ________.A. the sudden heart attack that drivers suffer fromB. the explosive outbursts of anger shown by motoristsC. traffic accidents arising from bad-tempered driversD. the panic caused by traffic congestions65. All of the following are considered a source of stress during car driving EXCEPT _______.A. heavy trafficB. traffic jamsC. unfamiliar roadsD. a sense of waste of time66. One of the advantages of a bus ride is that _______.A. you can do something productive on the roadB. there is no fear of taking the wrong roadC. no passenger suffers from high blood pressureD. you can get to your destination quickly67. This passage is intended to _______.A. urge the public to stop using cars altogetherB. advise people to take a bus instead of a car when possibleC. tell people how to ward off stress while driving a carD. highlight the causes of stress in a city68. Which of the following is an appropriate title for this passage?A. Car driving: a demanding but exciting jobB. Traffic jams: a source of diseases and conflictsC. Road rage: a frequent occurrence on the wayD. Bus travel: one third less stressful than the carPassage FourThe term ―g‖ (general intelligence) represents a measure of overall cognitive ability across a variety of tests. It‘s not the same as IQ but it does tend to correlate. Everyone agrees that ―g‖ tends to run in families. But is this down to genetics or to environmental influences?However, no single gene has yet been conclusively linked to intelligence. Rather it appears to be a case of complex interactions on many levels between many different genes.Identical twins have exactly the same genes, while non-identical twins share about half their genes. Another feature of twins that makes them an ideal choice for studies is that they tend to be raised in pretty much the same environment. If a particular feature is the same in identical twins, but not in non-identical twins, then chances are it‘s mainly genes that are controlling that feature.So what do the twin studies show? Well, first degree relatives tend to have ―g‖ correlation of about 0.4 -0.5. (Perfect correlation is 1; correlation of 0 means that the 2 things in question are totally unrelated). Identical twins have a correlation of 0.85, while for non–identical twins it‘s about 0.6. Which suggests that genes play a very important role, but are not the only factor, since if they were, the correlation between identical twins would be 1.Identical twins reared apart are almost as similar in ―g‖scores as those reared together. Adopted children and their adoptive parents have a ―g‖ correlation of zero, while adopted children and their biological parents tend to have the same correlations as any parent–child pair. So although genes don‘t seem to be the only thing affecting intelligence, their effects seem to be constant and apparently not overridden by environment.Does heritability of intelligence alter over a lifetime? Remarkably, it appears so. ―g‖heritability climbs gradually from 20% in babies to 40% in children, peaking at 60% in adults. Why this should be is still a matter of speculation. It‘s been suggested that as our cognitive abilities become more complex, new genes may come into play that were not needed when brain functions were less sophisticated. Or individuals may be drawn towards environments that fit with their genetic makeup, as time goes by and genetic effects that started out small in childhood build up together during adulthood.69. All of the following statements about ―g‖ are true EXCEPT _______.A. ―g‖ is to some extent inheritedB. ―g‖ correlates with IQC. ―g‖ can be attributed to a single geneD. ―g‖ is a measure of cognitive ability70. Identical twins are chosen as the subjects of the study because _______.A. they have the same genes and live in the same environmentB. they have some genes linked to general intelligenceC. they have the same heritability of intelligenceD. they are alike in everything except for intelligence71. The studies on twins‘ general intelligence show that _______.A. nothing but genes can determine ―g‖B. genes play an important role in ―g‖C. the correlation between identical twins is 1D. identical twins are more intelligent72. It can be inferred from Paragraph 5 that _______.A. environment plays a more important role in ―g‖ than genesB. an adopted child can become as clever as the step-parentsC. ―g‖ changes with the living environmentD. parenting has less effect on one‘s ―g‖ than genes73. It can be concluded from the passage that _______.A. it is easy to identify what determines our intelligenceB. genes are a more important determinant of ―g‖ than environmentC. identical twins have exactly the same IQD. IQ depends more on environment than on genes74. It seems that heritability of intelligence _______.A. has been clearly explainedB. declines as we grow upC. increases with our ageD. remains unchanged all our lifePassage FiveI was born on the last day of February. I‘ve always felt sorry for February, squeezed between the big months of January (named for the Roman god Janus, keeper of gateways) and March (after Mars, the god of war).The first Roman calendar, legend has it, had 10 months and no February. Beginning at the vernal equinox (春分) with March, it ended with December. In an agricultural society, winter wasof little importance, and thus went undivided.January and February were added about 700 B.C. by the second king of Rome, Numa Pompilius. He made all the months 29 or 31 days, but shortened February, the last month of the year, by giving it only 28.By the time of Julius Caesar, the calendar was three months out of sync with the solar year. This prompted Caesar to announce a new calendar in 46 B.C. Although there is some dispute—some historians say Caesar gave February 29 days—most believe his calendar preserved a 28-day February (with 29 days only in a leap year).Next, it was the church‘s turn. In 1582 Pope Gregory XIII decreed a new calendar in Europe. Many changes were made, but the Pope passed up yet another chance to grant February equality with the other months.It‘s messy, even dangerous, changing how we measure time, but Pope Gregory was hardly the last one to try. The League of Nations received over 150 new calendar designs, and the United Nations has considered more proposals since. Just to name a few, there‘s the 30x11 Calendar (which supersizes December to 35 or 36 days) and the Kluznickian Calendar (which adds the month of Aten, after an Egyptian sun god). Each proposal involves something that supposedly modernizes the calendar.But I have a simpler proposal that won‘t lead to chaos, and will correct the historical injustices against February: move the last day of January and the last day of March into February to make it a normal month with 30 days, and a respectable 31 on leap years. This would not add or subtract a single day from the calendar year.As an added benefit, making the first three months of the year each 30 days would bring them into closer alignment with the lunar cycle. It‘s a great idea. And unlike Julius and Augustus, I won‘t even demand a month named in my honor.75. It is said that in the first Roman calendar, ________.A. all months were equally dividedB. December was the longest monthC. February was the shortest monthD. January and February were merged into one76. The 12-month calendar was first announced by ________.A. Julius CaesarB. Pope Gregory XIIIC. AugustusD. Numa Pompilius77. According to most historians, the new calendar in 46 B.C. ________.A. gave February 29 days for the first timeB. unveiled many mysteries surrounding FebruaryC. followed the tradition on FebruaryD. made February equal with other months78. It is implied in the passage that ________.A. most people today are not interested in changing the calendarB. there is no point in changing the current calendarC. people have been trying to make changes to the calendarD. it is urgent for us to make improvements to the calendar79. The author suggests in the last paragraph that his proposal ________.A. is easy to carry outB. is simpler than the othersC. will trigger little disputeD. makes scientific sense80. The author‘s purpose in writing the passage is to ________.A. emphasize that February should be extendedB. rewrite the history of February in the calendarC. explain why February should be the shortest monthD. compare various proposals to make February longerPAPER TWOPART V TRANSLATION (30 minutes, 20 points)Section A (15 minutes, 10 points)No one is going to spend much time deciding whether to read a printed advertisement or listen to a spoken one. If their attention is not attracted in no time and held firmly for the short amount of time necessary to absorb what is being said, then the advertisement will have failed miserably. The language of advertising, therefore, must be a language of immediate impact and rapid persuasion. It must bring the advertised product into attention, highlight its qualities, clearly outline the reason for buying it, and, preferably, leave a memorable echo of what has been said about the product ringing in the reader‘s or listener‘s mind.Section B (15 minutes, 10 points)有些大学毕业生容易找到工作,他们的特点是学习成绩好,愿意从事低收入的工作。
2011年攻读硕士学位研究生入学考试试卷(陶瓷工艺原理)
一、名词解释(共30分,每题5分)
1. 陈腐:经过细磨后的坯料,陈放一段时间后可使水分均匀,提高性能。
2. 压力注浆:采用加大泥浆压力的方法,来加速水分扩散,从而加速吸浆速度。
3. 浸釉:将坯体浸入釉浆,利用坯体的吸水性或热坯对釉的粘附使釉料附着在坯体上
4. 泥浆的触变性:粘土泥浆或泥团受到振动或搅拌后黏度会降低而流动性增加,静置后逐渐恢复原状。
此外,泥浆静置一段时间后,在维持原有水分的情况下也会变稠和固化现象
5. 静电施釉:将釉浆喷至一个不均匀的电场,使厚为中性离子的釉料带有负电荷,随同压缩空气向带有正电荷的坯体移动。
从而达到施釉的目的。
6. 正釉与负釉前者:当釉的热膨胀系数小于坯的热膨胀系数时,坯体对釉产生压应力。
后者:当釉的热膨胀系数大于坯的热膨胀系数时,坯体对釉产生张应力。
二、简答题(共20分,每题5分)
1.可塑性指标是什么?
答:粘土泥团受外力作用下最初出现裂纹时应力与应变的乘积。
2.试列出二种辐射干燥的名称。
答:高频干燥,微波干燥,红外干燥。
3.烧成温度和烧结温度有何异同?
答:烧成温度指为了达到某种性能要求,应达到的最高温度。
烧结温度指材料加热过程达到气孔率、密度最大时的温度,是一定的范围。
4.分别简述一次莫来石与二次莫来石的形成机理及显微形貌。
答:1200℃左右,长石熔体中碱离子扩散到粘土分解区,促使粘土形成一次鳞片状莫来石。
1200℃~1250℃,莫来石和方石英突然增多,同时长石熔体中K2O降低,中心部位向莫来石析晶区变化,导致长石熔体中析出二次针状莫来石。
三、分析论述题(共100分)
1. 影响陶瓷材料强度的因素有哪些?(15分)
答:①气孔率:陶瓷材料的强度随气孔率的增加而降低,气孔的存在一方面使承受负荷的有效截面积减少;另一方面会引起应力集中而强度降低。
此外弹性模量会随气孔率增加而降低,间接影响强度
②晶粒的大小与裂纹:晶粒越大强度越小,陶瓷坯体出现的裂纹通常和晶粒尺寸成正比。
③晶相的数量和形貌:晶相的强度比玻璃相高,对于含玻璃相多的陶瓷来说,瓷坯中晶相含量愈多则其强度越大。
④晶界:由单一晶相组成的陶瓷材料在外力作用下扩展的裂纹遇到晶界往往会终止。
若晶界上有气孔存在而出现应力集中,则裂纹会沿晶界伸长。
2. 为什么干燥时希望温度梯度与湿度梯度的方向一致,如何实现?试举例说明。
(15分)答:如果温度梯度与湿度梯度方向一致,则内扩散速度将大大加快,采用电热干燥,微波干燥,远红外干燥等方法,可以向生坯中自由水直接提供热量使之转化为热能,达到热湿传导方向一致。
采用工频电干燥,对坯体端面间的整个厚度同时进行加热,热扩散与湿扩散方向一致。
3. 试述钾长石和钠长石在陶瓷制备中的作用,以及这两种长石在使用时的不同之处。
为什么利用辊道窑生产墙地砖时可以在坯体中使用含钠长石多的原料?(15分)
答:长石在陶瓷生产中的作用:①是坯料中氧化钾和氧化钠的主要来源;起熔
剂作用,有利于成瓷和降低烧成温度。
②长石熔体能溶解部分高岭土分解产物和石英颗粒,在液相中氧化铝和氧化硅相互作用,促进莫来石生成。
③长石熔体填充于各晶体颗粒之间,
提高坯体致密度,透明度等。
④是釉的主要熔剂⑤起瘠性物料作用。
瓷坯中主要采用钾长石,高温粘度大,随温度变化粘度变化速度慢,熔融范围宽,有利于瓷的形成。
保证在成瓷温度下提供足够的玻璃相,使坯体良好烧结。
钠长石高温粘度小,流动性大,产品易于变形,烧时不易控制。
辊道窑生产强度砖时,烧成温度较低,不需要很宽的熔融温度范围。
而钠长石熔融温度低,可以在较低温度下出现液相,可以使用含钠长石多的原料。
4. 如何实现陶瓷的低温快烧?(15分)
●坯釉料要适应低温烧成条件:①干燥收缩和烧成收缩小、②坯料热膨胀系数、③坯料的
热传导性、抗热震性能能好④坯料少含晶型转变的物质。
⑤釉料始熔温度高,高温粘度低。
●减少坯体入窑水分,提高坯体入窑温度。
●控制坯体形状、大小、厚度。
●选用温差小和保温性能良好的窑具。
5. 陶瓷材料的晶粒细小有什么好处?为什么?请说明要制备出晶粒细小的陶瓷材料应当采用什么措施?(20分)
答:①原料的晶粒应当更为细小或者在烧成时通过分解或者化学反应形成细小晶体;
②加入限制晶粒长大的物质;③非常短的时间内快速烧成,如等离子体烧结、微波烧结等;
④采取措施降低烧结温度,如通过加压(热等静压等)或者超细的原料、加入适当的烧结助剂等;⑤烧成制度要合理,适当减少在高温的时间,增加中温时间。
6. 试述氧化硅、氧化铝、氧化钾、氧化钠在陶瓷中的作用,它们通常分别由什么矿物获得?(20分)。