水泥胶砂强度检验方法(ISO法)规定，制备水泥胶砂试样的比例为水泥：标-我要搜题网

[单项选择]The railroad industry could not have grown as large as it did without steel. The first rails were made of iron. But iron rails were not strong enough to support heavy trains running at high speeds. Railroad executives wanted to replace them with steel rails because steel was ten or fifteen times stronger and lasted twenty times longer. Before the 1870’s, however, steel was too expensive to be widely used. It was made by a slow and expensive process of heating, stirring, and reheating iron ore.
Then the inventor Henry Bessemer discovered that directing a blast of air at melted iron in a furnace would burn out the impurities that made the iron brittle (易碎的). As the air shot through the furnace, the bubbling metal would erupt in showers of sparks. When the fire cooled, the metal had been changed, or converted, to steel. The Bessemer Converter made possible the mass production of steel. Now three to five tons of iron could be changed into steel in a mater of minutes.
Just whe
A. It directed air at melted iron in a furnace, removing all impurities.
B. It slowly heated iron ore, then stirred it and heated it again.
C. It changed iron ore into iron, which was a substitute for’ steel.
D. It could quickly find deposits of iron ore under the ground.

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[判断题]导体对电流的阻碍作用祢为电阻。( )
A.正确
B.错误

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[多选题]当循环水泵的电动机发生（）时，可紧急停车。
A.故障
B.发热
C.着火
D.电流超过规定

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[简答题]任何组织和个人不得招用未满几周岁的未成年人？

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[判断题]强化上级纪委对下级纪委的领导,纪委发现同级党委主要领导干部的问题,可以直接向上级纪委报告。( )
A.正确
B.错误

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[单项选择]下列哪一种不是工艺专业化的特点（）。
A. 配备相同工种的工人
B. 集中了同类型的设备
C. 加工的工件相类似
D. 加工的工艺方法相同

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[判断题](判断题）
高利转贷罪的犯罪主体是特殊主体
正确︱错误
A.正确
B.错误

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[填空题]研究生读者撰写学位毕业论文阅读需要表现为学习型与（）相结合的阅读需要特点。

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[单选题]硫化氢的爆炸极限为()%。
A.12.5至74
B.4.3至46
C.4至74

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[简答题]试述腹外疝的术后护理。

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[单选题]足三阳经的走向规律是( )
A.从足走头
B.从头走足
C.从胸走手
D.从手走头
E.从足走腹

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[单项选择]
阅读下面短文，从短文后所给的[A]、[B]、[C]三个选项中选出能填人相应空白处的最佳选项。

It doesn’t matter when (Example: {{U}} (0) ){{/U}} {{U}} (41) {{/U}} a person sleeps, but everyone needs some rest to stay alive.
That’s {{U}} (42) {{/U}} all doctors thought, until they heard about A1 Herpin. People said he never {{U}} (43) {{/U}} . Could this be true’ . The doctors decided to see this strange man {{U}} (44) {{/U}} . A1 Herpin was 90 years old when doctors went to his home. They {{U}} (45) {{/U}} that he got some sleep of some kind. So they stayed with him and watched him. But they were {{U}} (46) {{/U}} . Though they watched him hour {{U}} (47) {{/U}} hour and day after day, they never saw Herpin sleeping. In fact, he did not even have a bed. He never needed one. The only rest he got was {{U}} (48) {{/U}} in a chair and reading newspapers. The doctors were puzzled(疑

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[单选题]下列哪项不是预防疲溃的原则( )
A.培养轻松、健康的业余爱好
B.每天坚持体育锻炼
C.支持系统,寻求可倾诉的对象
D.自信、自立、自强
E.克服失落感

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[单项选择]产后大约有2%〜4%的产妇会发生泌尿系统感染，感染途径主要为：（）
A. 上行性感染
B. 自身感染
C. 血行感染
D. 体液感染
E. 接触感染

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[单项选择]现行《选举法》规定的县级人大代表名额基数是（）
A. 80名
B. 100名
C. 120名
D. 150名

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[单项选择]根据有关规范要求,下列何值是建筑物室外通路上通行轮椅车的坡道宽度的最小限值?
A. 1.00m
B. 1.20m
C. 1.50m
D. 2.00m

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[判断题]只有沉淀称量法属于重量分析法。
A.正确
B.错误

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[判断题]弹条V型扣件系统由螺旋道钉、平垫圈、弹条、轨距挡板、轨下垫板和预埋套管等组成，此外，为高低调整需要，还包括调高垫板。
A.正确
B.错误

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[判断题]在我国及欧洲,燃料经济性指标的单位L/100km,即每行驶100km所消耗的燃料升数。它的数值越小,消防车燃料经济性越差。( )(中)
A.正确
B.错误

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[单项选择]下列关于淋巴按摩推抹颈肩部的说法，哪项是错误的（）。
A. 被按摩者取仰卧位
B. 反复操作5～8次
C. 按摩师用食、中、无名指自肩胛内上缘推抹至颈项部
D. 按摩师用食、中、无名指自腋下推抹至颈项部

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[单项选择]水泥胶砂强度检验方法(ISO法)规定，制备水泥胶砂试样的比例为水泥：标准砂：水=( )。
A. 1:3:0.5
B. 1:3:0.45
C. 1:2.5:0.5
D. 1:2.5:0.45

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[单项选择]水泥胶砂强度检验方法(ISO法)规定，制备水泥胶砂试样的比例为水泥：标准砂：水=( )。A. 1:3:0.5B. 1:3:0.45C. 1:2.5:0.5D. 1:2.5:0.45

热门试题:

[单项选择]水泥胶砂强度检验方法(ISO法)规定，制备水泥胶砂试样的比例为水泥：标准砂：水=( )。
A. 1:3:0.5
B. 1:3:0.45
C. 1:2.5:0.5
D. 1:2.5:0.45