如图所示,两根相距为l的平行直导轨ab、cd、b、d间连有一固定电阻R,导轨电阻

题型:选择题

问题:

如图所示,两根相距为l的平行直导轨ab、cd、b、d间连有一固定电阻R,导轨电阻可忽略不计;MN为放在ab和cd上的一导体杆,与ab垂直,其电阻也为R;整个装置处于匀强磁场中,磁感应强度的大小为B,磁场方向垂直于导轨所在平面(指向图中纸面内);现对MN施力使它沿导轨方向以速度v(如图)做匀速运动;令U表示MN两端电压的大小,则(  )

A.U=vBl,流过固定电阻R的感应电流由b到d

B.U=vBl,流过固定电阻R的感应电流由d到b

C.U=vBl,流过固定电阻R的感应电流由b到d

D.U=vBl,流过固定电阻R的感应电流由d到b

考点:右手定则导体切割磁感线时的感应电动势
题型:选择题

根据以下材料回答问题。

世界卫生组织最近公布,全球约有11亿人抽烟,其中男子9亿,女子2亿,约占全球l5岁以上人口的1/3。平均每位吸烟者每天消耗香烟15支,发达国家与发展中国家分别为22支和14支。

全球15岁以上的人口数为()。

A.27亿

B.6亿

C.21亿

D.33亿

题型:选择题

She devoted herself _____ to her research and it earned her a great reputation in her field. [ ]

A. strongly

B. extremely

C. entirely

D. freely

题型:选择题

阅读表达(共5小题;每小题3分, 共15分)

阅读下面短文, 请根据短文后的要求进行答题(请注意问题后的字数要求)。

〔1〕The harmful effects on children were summed up last year in a report by the National Research Council and Institute of Medicine. Problems begin early, as the infants of depressed mothers cry more than other babies. They have greater fear of strangers and less tolerance for frustration. Starting in preschool and across all stages of childhood, they have more behavior problems at school and higher rates of depression and anxiety disorders.

〔2〕By adolescence, children with depressed parents have poorer social relations than the teens of parents________, and they’ re more likely to be dependent on alcohol and drugs. Depression in parents also is linked to more behavior problems at school and higher rates of depression and anxiety disorders, according to studies in the report.

〔3〕And some harmful effects of growing up with a depressed parent appear to remain intoadulthood. A 20-year study on kids of depressed parents found that those with depressed parents suffered about three times the rate of anxiety disorders and depression by their 30s, and they were in poorer health than peers and much more likely to be dependent on drugs and alcohol. The study, believed to be the longest ever done, was published in the American Journal of Psychiatry in 2006. These effects may not only be longlasting but also farreaching. Serious depression affects about one in five American parents, and 15.6 million children live with an adult who has had major depression in the last year. 

〔4〕As knowledge about the effects of parental depression has grown, so too has research into how to fight those effects. Studies suggest, for example, that changing destructive parenting practices and teaching children good coping strategies can make a big, positive difference in kids.

76. What is mainly talked about in the text? (no more than 10 words)

_______________________________________________________________________________

77. Which sentence in the text is closest in meaning to the following one? 

With a better understanding of the effects of depressed parents, research is also being conducted on how to prevent those effects.

_______________________________________________________________________________

78. Fill in the blank in Paragraph 2 with proper words. (no more than 5 words)

_______________________________________________________________________________

79. List three negative effects of parental depression on children. (no more than 20 words)

①_______________________ ②_______________________ ③____________________

80. Translate the underlined sentence in Paragraph 3 into Chinese.

_______________________________________________________________________________

题型:选择题

新鲜冰冻血浆(FFP)、普通冰冻血浆(FP)的正确保存条件是()

A.0℃以下

B.-20℃以下

C.-25℃以下

D.-30℃以下

E.-80℃以下

题型:选择题

改革开放是前无古人的崭新事业,必须坚持正确的方法论。摸着石头过河,是富有中国特色、符合中国国情的改革方法。要鼓励大胆试验、大胆突破,不断把改革开放引向深入。摸着石头过河和加强顶层设计是辩证统一的,推进局部的阶段性改革开放要在加强顶层设计的前提下进行,加强顶层设计要在推进局部的阶段性改革开放的基础上来谋划。

结合材料,运用实践与认识辩证关系的知识,说明应如何深入推进改革开放。

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