北京奥委会接受专家的建议,大量采用对环境有益的新技术.如奥运会场馆周围80%~9

题型:选择题

问题:

北京奥委会接受专家的建议,大量采用对环境有益的新技术.如奥运会场馆周围80%~90%的路灯将利用太阳能发电技术、奥运会90%的洗浴热水将采用全玻真空太阳能集热技术.太阳能的产生是由于太阳内部高温高压条件下的热核聚变反应形成的,其核反应方程是(  )

A.+

B.++

C.+++10

D.+

考点:天然放射现象核反应
题型:选择题

茶是我国人民喜爱的饮品,其中含有多种有益于人体健康的成分,据测定茶叶中含有450种以上的有机成分与15种以上的元素.某化学研究小组欲探究茶叶中钙元素的含量,设计了探究实验方案如下:(已知茶叶中的铝、铁元素对钙离子的测定有影响)

步骤1:称取500克干燥的茶叶,置于通风橱中,充分灼烧使茶叶灰化,再用研钵磨细后移入烧杯中,然后将200mL 1mol•L-1盐酸加入灰中搅拌、过滤、洗涤.

步骤2:向步骤1所得滤液中逐滴加入稀氢氧化钠溶液,调节溶液的pH为6~7左右,使铝、铁的氢氧化物完全沉淀,再加热煮沸30min,加入7.95g无水碳酸钠,充分搅拌,待沉淀完全后,过滤,洗涤,过滤后得到滤液和沉淀.

步骤3:将步骤2所得的滤液稀释至500mL,取其中的20.00mL溶液以甲基橙作指示剂,用0.1000mol.L-1的HCl标准溶液滴定,终点时消耗盐酸的体积为20.00mL,计算结果.请回答下列问题:

(1)步骤 1中,使茶叶灰化需要三角架、泥三角、酒精喷灯、______、______等仪器.

(2)步骤2中,判断沉淀已经洗涤干净的方法是______.

(3)步骤3中,滴定操作时,眼睛注视______.被滴定的20mL滤液中 CO32-的物质的量为______mol,原茶叶中钙离子的质量分数为______.

题型:选择题
Reading comprehension.

    Personal computers and the Internet give people new choices about how to spend their time.
    Some may use this freedom to share less time with certain friends or family members, but new technology
will also let them stay in closer touch with those they care most about. I know this from personal experience.
    E-mail makes it easy to work at home, which is where I now spend most weekends and evenings. My
working hours aren't necessarily much shorter than they once were but I spend fewer of them at the office.
This lets me share more time with my young daughter than I might have if she'd been born before electronic
mail became such a practical tool.
    The Internet also makes it easy to share thoughts with a group of friends. Say you do something fun-see a
great movie perhaps-and there are four or five friends who might want to hear about it. If you call each one,
you may tire of telling the story.
     With E-mail, you just write one note about your experience, at your convenience, and address it to all the
friends you think might be interested. They can read your message when they have time, and read only as
much as they want to. They can reply at their convenience, and you can read what they have to say at your
convenience.
     E-mail is also an inexpensive way to stay in close touch with people who live far away. More than a few
parents use E-mail to keep in touch, even daily touch, with their children off at college.
     We just have to keep in mind that computers and the Internet offer another way of staying in touch. They
don't take the place of any of the old ways.

1. The purpose of this passage is to _____.
[ ]
A. explain how to use the Internet
B. describe the writer's joy of keeping up with the latest technology
C. tell the merits (价值) and usefulness of the Internet
D. introduce the reader to basic knowledge about personal computers and the Internet
2. The use of E-mail has made it possible for the writer to _____.
[ ]
A. spend less time working
B. have more free time with his child
C. work at home on weekends
D. work at a speed comfortable to him
3. According to the writer, E-mail has an obvious advantage over the telephone because E-mail helps one _____.
[ ]
A. reach a group of people at one time conveniently
B. keep one's communication as personal as possible
C. pass on much more information than the telephone
D. get in touch with one's friends faster than the telephone
4. The best title for this passage is _____.
[ ]
A. Computer: New Technological Advances
B. Internet: New Tool to Maintain Good Friendship
C. Computers Have Made Life Easier
D. Internet: a Convenient Tool for Communication
题型:选择题

下列选项中,不属于社区党组织主要职责的是()

A.领导社区居民自治组织

B.做好党的教育管理工作

C.联系群众,反映群众的意见和要求

D.组织居民参与公共政策的听证活动

题型:选择题

十八届四中全会对法治体系的内涵做出明确规定,即()

A.形成高效的的法律规范体系、完备的法治实施体系、有力的法治监督体系、严密的法治保障体系,形成完善的党内法规体系

B.形成有力的法律规范体系、高效的法治实施体系、完善的法治监督体系、完备的法治保障体系,形成严密的党内法规体系

C.形成完备的法律规范体系、高效的法治实施体系、严密的法治监督体系、有力的法治保障体系,形成完善的党内法规体系

D.形成完善的法律规范体系、高效的法治实施体系、严密的法治监督体系、完备的法治保障体系,形成有力的党内法规体系

题型:选择题

患者,男,32岁。既往有胃病史,近1周来,常感上腹部不适,4小时前突发上腹部剧烈疼痛,伴有恶心、呕吐,体格检查:腹部压痛、肌紧张,肝浊音界缩小,X线检查可见膈下游离气体,首先应考虑为()

A.急性阑尾炎穿孔

B.胆囊炎穿孔

C.急性胰腺炎

D.溃疡病穿孔

E.急性肠梗阻

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