pH值大小影响粘土水化分散程度。如果pH值过低，则（）。-我要搜题网

[填空题]Fifty years from now the world’s population will be declining, with no end in{{U}} (36) {{/U}}.Several centuries from now, unless people’s values changes{{U}} (37) {{/U}}, there could be fewer people living in the entire world than live in the United States today. The big{{U}} (38) {{/U}}of the past twenty years is that in not one country did fertility stop falling when it reached the{{U}} (39) {{/U}}rate -- 2.1 children per women. In Italy, for example, the rate has{{U}} (40) {{/U}}to 1.2. In Western Europe as a whole and in Japan it is down to 1.5. The evidence now{{U}} (41) {{/U}}that within fifty years or so world population will{{U}} (42) {{/U}}at about eight billion before starting a{{U}} (43) {{/U}}rapid decline. That has really posed a great deal of anxiety.{{U}} (44) {{/U}}, many people still fear that it will keep "exploding" until there are too many people for the earth to support. But{{U}} (45) {{/U}}. World population was growing by two percent a year in the 1960s; the r

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[单项选择]《山东省工业压力管道安全管理暂行规定》中所称的工业管道，不包括（）
A. 管道安全保护装置
B. 管道附属设施
C. 长输管道
D. 辅助管道

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[单选题]764.割心采用上提钻具拔断岩心时，应在钻完进尺后停止送钻，但不停泵，以原转速旋转(　　)左右，待重恢复后，停止转盘转动，缓慢上提钻具拔断岩心。
A.A、3min
B.B、5min
C.C、10min
D.D、15min

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[单项选择]舞蹈的整体结构即舞蹈的（）。
A. 效果
B. 内容
C. 语篇
D. 剧目

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[单选题]禁止作业人员越过（）的线路对上层线路、远侧进行验电。
A.未停电
B.未经验电、接地
C.未经验电
D.未停电、接地

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[单选题]线路平板车在线路上运行时，其最高运行速度是(　　)。　
A.A.10km/h
B.B.15km/h
C.C.20km/h
D.D.25km/h

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[简答题]

电动汽车的发展已成为新能源汽车发展的主流，各国将其纳入国家战略，电动汽车产业将成为新一轮产业竞争的战略高地。我国政府先后发布了《汽车产业调整和振兴规划》和《私人见习新能源汽车试点财政补助资金管理暂行办法》等政策文件，以大力推动新能源汽车产业，尤其是电动汽车产业的发展。
分别从政府职能和参与国际竞争的视角简要说明我国政府推动电动汽车产业发展的原因。

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[单选题]对脑和长骨的发育最为重要的激素是
A.生长素
B.性激素
C.甲状腺激素
D.促甲状腺激素
E. 1..,25..-二轻维生素D3..

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[判断题]停工或过夜时，应将起吊滑车组收紧在地面固定。不得悬吊构件在空中停留过夜。
A.正确
B.错误

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[多项选择]员工仪表形象包括（）
A. 容貌形象
B. 服饰形象
C. 体态形象
D. 货品陈列形象

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[单选题]下列各项中对变压器绕组直流电阻的测得值有影响的是( )。
A.环境空气湿度
B.变压器上层油温（或绕组温度）
C.变压器散热条件
D.变压器油质试验结果

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[填空题]四大危险是指()。

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[判断题]白肋烟质量随颜色变化规律为：近红黄、红黄～浅红黄、棕红～浅黄依次降低。(　　)
A.正确
B.错误

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[单选题]患者男性，44岁。扩大胰十二指肠术后，深静脉置管，鼻胃管、鼻空肠管及胃造瘘管，现为术后第3天，最好采取何种方式增加营养 A.静脉滴注高糖、脂肪乳剂及氨基酸
A.全营养混合液(TN
B.
C.鼻胃管滴注营养液
D.胃造瘘管注入营养液
E.鼻空肠管滴注营养液

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[单项选择]Space enthusiasts look to the day when ordinary people, as well as professional astronauts and members of Congress, can leave Earth behind and head for a space station resort, or maybe a base on the moon or Mars. The Space Transportation Association, an industry lobbying group, recently created a division devoted to promoting space tourism, which it sees as a viable way to spur economic development beyond Earth. The great stumbling block in this road to stars, however, is the sheer difficulty of getting anywhere in space. Merely achieving orbit is an expensive and risky proposition. Current space propulsion technologies make it a stretch to send probes to distant destinations within the solar system. Spacecraft have to follow multi-laver, indirect trajectories that loop around several planes in order to gain velocity from gravity assists. Then the craft lack the energy to come back. Sending spacecraft to other solar systems would take many centuries. Fortunately, engineers have no shortage of inventive plans for new propulsion systems that might someday expand human presence, literally or figuratively, beyond this planet. Some are radical refinements of current rockets or jet technologies. Others harness nuclear energies or would ride on powerful laser beams. Even the equivalents of "space elevators" for hoisting cargoes into orbit are on the drawing board. "Reach low orbit and you are halfway to anywhere in the Solar System", science-fiction author Robert A. Heinlein memorably wrote, and virtually all analysts agree that inexpensive access to low Earth orbit is a vital first step, because most scenarios for expanding humankind"s reach depend on the orbital assembly of massive spacecraft or other equipment, involving multiple hunches. The need for better launch systems is already immediate, driven by private and public sector demand. Most commercial payloads are destined either for the now crowed geo-stationary orbit, where satellites jostle for elbow room 36,000 kilometers above the equator, or for low-Earth or bit, just a few hundred kilometers up. Low-Earth orbit is rapidly becoming a space enterprise zone, because satellites that close can transmit signals to desktop or even handheld receivers. Scientific payloads are also taking off in a big way. More than 50 major observatories and explorations to other solar systems" bodies will lift off within the next decade. The pressing demand for launches has even prompted Boeing"s commercial space division to team up with RSC—Energia in Moscow and Kvaerner Maritime in Oslo to refurbish an oil rig and create a 34,000—ton displacement semi-submersible launch platform that will be towed to orbitally favorable launch sites.Which of the following is true, according to the passage
A. Current rockets are vulnerable and unstable.
B. New propulsion system has been developed.
C. People consider loser beams as a possible solution to developing new propulsion system.
D. At present, nuclear energies can be used in propulsion systems.

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[单项选择]下列哪种不是碱石灰中常用的指示剂（）
A. 酚酞
B. 溴甲酚绿
C. 陶土黄
D. 甲基橙
E. 乙酯紫

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[单项选择]黏液脓血便见于
A. 上消化道出血
B. 阿米巴痢疾
C. 痔或肛裂
D. 急性细菌性痢疾
E. 急性出血性坏死性肠炎

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[单项选择]国有土地使用权出让的，其契税的计税依据是
A. 土地的市场价格
B. 土地的成交价格
C. 土地的评估价格
D. 国土局确定的价格

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[单选题]主动转运是：（ C）。逆浓度梯度转运
A.从浓度高的一侧向浓度低的一侧扩散
B.耗能，不受饱和限速和竞争抑制的影响
C.逆浓度梯度转运
D.受脂溶性和极性等因素影响

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[单项选择]《房地产估价规范》条文说明中给出了钢结构房屋的经济耐用年限的参考值如下：生产用房70年，受腐蚀的生产用房50年，非生产用房（）年。
A. 50
B. 60
C. 70
D. 80

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[简答题]高血压病的临床分期标准如何？