水是人类赖以生存必不可少的一种.下列关于水的说法中,缺乏科学依据的是( ) A.

题型:选择题

问题:

水是人类赖以生存必不可少的一种.下列关于水的说法中,缺乏科学依据的是(  )

A.将海水淡化解决人类面临的淡水危机

B.用水在一定条件下制取氢气解决能源危机

C.废水经处理后再利用以达到节约用水目的

D.将水变成油解决能源危机

考点:水污染与防治质量守恒定律
题型:选择题

有以下程序: #include <stdio.h> int fun(char s[]) { int n=0; while(*s<='9'&&*s>='0') {n=10*n+*s-'0';s++;} return(n); } main() { char s[10]={'6','1','*','4','*','9','*','0','*'};printf("%d\n",fun(s)); } 程序的运行结果是( )。

A.9

B.61490

C.61

D.5

题型:选择题

抑菌剂()。

A.盐酸普鲁卡因

B.苯甲醇

C.硫代硫酸钠

D.明胶

E.葡萄糖

题型:选择题

Situated in the Northeast region of Vietnam, Halong Bay is made up of 1,969 islands of various sizes, 989 of which have been given names. The concentrated zone of stone islands is famous for its spectacular scenery of caves, and forms the central zone of Halong Bay.

Seen from above, Halong Bay looks like a geographic work of art. While exploring the bay, you feel lost in a wonderful world. There is Man’s Head Island, which resembles a man standing and looking towards the mainland. Dragon Island looks like a dragon winding above the blue water. La Vong Island resembles an old man fishing. There are also the islands of the Sail, the Pair of Roosters, and the Incense Burner, which are all astonishingly like their names.

It has been proven by scientists that Halong Bay was one of the first places of human existence. It is also a region of highly-concentrated biological diversity with many ecosystems of coral reefs, and tropical forests, which are home to thousands of species of animals and rare plants.

The beach located along the coast of Halong Bay has a year-round average temperature of 20℃. Among the palm trees are large hotels. Visitors are seen on white sand and under the green trees are small family-run restaurants. After swimming, tourists can enjoy cold drinks. No wonder the 18h meeting of the Committee of the World Heritages of UNESCO officially recognized Halong Bay as a natural heritage site of worldwide importance.

小题1:What forms the central zone of Halong Bay?

A.1,969 islands of various sizes.

B.The concentrated zone of stone islands.

C.989 islands that have been given names.

D.Man’s Head Island.小题2:We can infer that the names of most islands ______.

A.have something to do with theirs shapes.

B.were given by the visitors in Halong Bay

C.were given by the geologists of Vietnam

D.are related to their history小题3: The author writes the passage mainly to_______.

A.tell some information about the history of Vietnam

B.introduce the average temperature in Vietnam

C.introduce the beach of Vietnam

D.tell readers something about Halong Bay

题型:选择题

要测得肺毛细血管楔嵌压(PAWP)的值,则需漂浮导管()。

A.在左心房内

B.在肺小动脉内

C.在下腔静脉内

D.在左心室内

E.在肺动脉主干内

题型:选择题

背景

由某企业承建某多功能现代化商务综合大厦,地上46层,地下3层,全现浇钢筋混凝土框架一剪力墙结构,主体结构采用泵送混凝土等新技术。建筑物周边都十分接近规划用地红线,周边建筑及地下管线对因工程基坑开挖引起地层变形移动影响十分敏感,且基坑北面邻近地铁。该工程地下室基坑开挖深度较大,为确保基坑开挖安全编制了专项施工方案,专家论证并由安全总监签字确认后实施。该地下室位于总厚度达40多米的淤泥质土之中,根据本工程的特点,经多方案比较,决定基坑围护结构采用80cm厚的地下连续墙,而支护结构则为五道钢筋混凝土水平支撑的总体方案。经验算,可以满足结构变形和稳定要求,确保地下室开挖施工不至于影响地铁的正常运行、周边道路、建筑物及各种地下管线的正常使用。在工程施工中发生如下事件:

事件一:本工程地下水位较高,约为-0.5m,开挖范围位于淤泥质土体内,含水量大,施工必须事前采取降水措施,因基坑围护是采用地下连续墙,具有较好的挡水和抗渗性能。结合实际情况,决定采用轻型井点降水并编制了降水施工方案。

事件二:根据地质勘察资料、上部结构形式、荷载和施工条件等情况,基础施工采用人工挖孔扩底灌注桩与平板式筏形基础,板厚2m,桩基承台连同地下室的筏形基础同时展开施工。基础底板厚2m,桩基承台厚1.8m,混凝土强度等级C40,抗渗等级P8。由于承台和筏板混凝土浇筑量大,在开始阶段施工中出现了少许裂缝。为确保施工质量,项目部制定了以下控制裂缝的措施:

(1)优先选用低水化热的普通硅酸盐水泥拌制混凝土,并适当加人木质素磺酸钙减水剂。

(2)在保证混凝土设计强度等级的前提下,适当提高水灰比,减少水泥用量。

(3)降低混凝土的浇筑温度,控制混凝土内外温差在30℃以内。

(4)分层分块逐步浇筑,加强养护,及时对混凝土进行覆盖保温、保湿材料。

(5)预埋冷却管,通人循环水将混凝土内部降温。

事件三:在进行办公楼大厅顶盖模板支架预应力混凝土空心板现场浇筑施工时,发生模板支撑体系坍塌事故,造成6人死亡、12人受伤。经有关部门调查,造成事故主要原因是模板支架搭设质量不符合要求;现场搭设模板支架中使用的部分钢管材料存在质量缺陷;施工现场管理存在严重问题。事后,建设行政主管部门对该施工企业作了相应的行政处罚,公安机关依法对有关责任单位的涉案人员追究刑事责任。

事件三工程事故可定为哪级事故?并说明理由。

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