“中国当代文学”

实验室制取氧气的实践与研究．

（1）过氧化氢是一种无色透明的无毒液体，过氧化氢溶液俗称“双氧水”，具有强氧化性．贮运过氧化氢的试剂箱上最适合粘贴的一张标识是______（从图1中选填字母序号）．

（2）过氧化氢溶液常用于实验室制取氧气．可供选择的仪器或装置如图2所示．

①要以过氧化氢为原料制取氧气，应选择气体发生装置为______（选填字母A～E）；反应的化学方程式为______．

②MnO₂可以连续反应使用，因为MnO₂在反应前后______和______都不变；

③用D收集氧气，验证收集的氧气是否满的方法是______．

（3）生产火箭燃料的工业废水中含有少量偏二甲肼X，可用双氧水处理排污，反应的化学方程式为X+8H₂O₂=2CO₂↑+N₂↑+12H₂O，则X的化学式为______．

我国纬度最高的盆地是柴达木盆地．______．

《江苏省电力公司农村供电所办公后勤管理办法》适用于农村供电所（）等的管理。

A.办公后勤设备

B.农电工服装

C.农村供电所就餐

D.农电员工劳动用品

绝缘栅型场效应管通常称为（）、存放时应将三个电极（）。

Although no longer slavers after the Civil War, American blacks took no significant part in the life of white America except as servants or laborers. Many thousands of them emigrated from the war-ravaged South to the North from 1865 to 1915 in the hope of finding work in the big industrial cities. Whole communities of blacks crowded together into ghettos in New York City, Chicago and Detroit, where once the poor white immigrants had lived. These ghettos, neglected by the city authorities, became slums. The schools to which black children went were hopelessly inadequate. Unemployment in black ghettos remained consistently higher than in white communities.
41. Serious problems with black ghettos. ______
Stable family life was difficult to maintain.
42. The extreme poverty of the blacks. ______
In the late 1970s, nearly a third of all blacks still belonged to the so-called "underclass", they are so " under-privileged " and poor that they cannot seize the opportunity for advancement.
43. Efforts to put an end to racial discrimination. ______
Race relations in the USA continue to be a thorny problem.
44. Improvements in lives of the blacks. ______
Despite some setbacks, race relations are improving.
45. Prevailing violence in solving racial problems. ______
It is said that television had an enormous influence on frustrated and bitter blacks, for it showed them bow much better whites on the whole lived than blacks. At the end of the 1960s, there were serious riots in many cities.
The violence quickly died down. Blacks began to use their votes to exert political pressure. Cities like Atlanta (Georgia), Gary (Indiana), and Los Angeles (California) elected black mayors. Integration of schools, despite resistance from white groups, goes on, and the proportion of blacks in American colleges has increased dramatically in the last 20 years. There are reasons to maintain a cautious optimism that progress in race relations will continue.
[A] It has been estimated that there are more than 20 million Americans in this category, 10% of the population, including many millions of whites.
[B] Blacks are gaining in self-confidence. In more and more areas, they are winning control of their communities, and their standard of living is going up faster than that of the poor whites. It is still a hard struggle. There is still prejudice and even some hatred, but in most walks of American life there are now more blacks than ever before.
[C] The era of blatant discrimination ended in the 1960s through the courageous actions of thousands of blacks participating in peaceful marches and sitins, to force Southern states to implement the Federal desegregation laws in schools and public accommodations. Down came the " whites only" notices in bused, hotels, trains, restaurants, sporting events, restrooms and on park benches that once could be found everywhere throughout the South. Gone were the restrictions that prevented blacks voting. Gone, too, were the hideous lynchings, which since the Civil War had caused the death of thousands of innocent blacks-- hanged without trial by white mobs. However, even today, poor, uneducated lacks do not always receive the same degree of justice that the more affluent and better educated can expect.
[D] Many blacks chose to keep silent about their unfairness instead of resorting to violence. But their silence was also problem provoking: on the one hand, silence would build up a lot of complaints and hatred in their minds, thus resulting in a negative approach to life and everything; on the other hand, silence would give the whites an impression that the blacks take the reality for granted and put more racial discrimination on them.
[E] Unemployed fathers would on occasion walk out of their homes and never return. Children neglected by their parents turned in some instances to drugs and crimes. There are more than 700 murders a year in cities like New York, Detroit, Los Angeles and Houston, and most of these deaths are of blacks killed by blacks. The black ghettos are dangerous both for blacks and non-blacks.
[F] Radical blacks like the Black Panthers demanded a free black state within the Union, and advocated violence to achieve that end and to protect themselves against what they felt was police brutality toward blacks. For a while, violence overshadowed the influence of the greatly respected pacifist black, Martin Luther King, Jr. , who had provided the inspiration and leadership for those devoted to a peaceful change and whose murder in 1968 stunned America.