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问题 单项选择题

关于胃小区的叙述正确的是

A．均为圆形或类圆形

B．不是胃的微皱襞

C．正常胃小区1～3mm

D．由胃小凹组成

E．胃底部没有胃小区

答案

参考答案：C

解析：双对比造影能显示的黏膜皱襞的微细结构即胃小区、胃小沟。正常胃小区为1～3mm，呈圆形、椭圆形或多角形大小相似的小隆起。

单项选择题

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 (51) on the individual suggest that children engage in criminal behavior (52) they were not sufficiently penalized for previous misdeeds or that they have learned criminal behavior through (53) with others. Theories focusing on the role of society suggest that children commit crimes in response to their failure to rise above their socioeconomic status, (54) as a rejection of middle-class values. Most theories of juvenile delinquency have focused on children from disadvantaged families, ignoring the fact that children from wealthy homes also commit crimes. The latter may commit crimes (55) lack of adequate parental control. All theories, however, are tentative and are (56) to criticism. Changes in the social structure may indirectly (57) juvenile crime rates. For example, changes in the economy that lead to fewer job opportunities for youth and rising unemployment (58) make gainful employment increasingly difficult to obtain. The resulting discontent may in turn lead more youths into criminal behavior. Families have also (59) changes these years. More families consist of one-parent households or two working parents; consequently, children are likely to have less supervision at home (60) was common in the traditional family structure. This lack of parental supervision is thought to be an influence on juvenile crime rates.

55().

A.on 

B.in 

C.for 

D.with
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填空题

为倡导“节能减排”和“低碳经济”，降低大气中CO2的含量及有效地开发利用CO2，科学家正在研究如何将CO2转化为可利用的资源．目前工业上有一种方法是用CO2来生产燃料甲醇．一定条件下发生反应：

CO2（g）+3H2（g）⇌CH3OH（g）+H2O（g），

（1）图1表示该反应过程中能量变化，则该反应为______反应（填“吸热”或“放热”），判断依据是______；

（2）某实验小组依据甲醇燃烧的反应原理，设计如图2所示的电池装置．

①该电池正极的电极反应式为：______；

②工作一段时间后，测得溶液的pH减小，该电池总反应的化学方程式为：______；

（3）已知在常温常压下：

①2CH3OH（l）+3O2（g）=2CO2（g）+4H2O（g）△H=-1275.6kJ/mol

②2CO（g）+O2（g）=2CO2（g）△H=-566.0kJ/mol

③H2O（g）=H2O（l）△H=-44.0kJ/mol

写出甲醇不完全燃烧生成一氧化碳和液态水的热化学方程式：______；

（4）为了消除污染，在一定条件下，向含有甲醇的废水中加入一定量的稀硝酸，会有N2等物质生成．若参加反应的氧化剂和还原剂的物质的量之比为6：5，写出该反应的化学方程式______；在此反应过程中若消耗32g 甲醇，将转移______mol 电子．
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