如图是上海世博会使用的两种降温方法:冰块降温和喷雾降温.工作人员刚从冷库中搬出的

题型:填空题

问题:

如图是上海世博会使用的两种降温方法:冰块降温和喷雾降温.工作人员刚从冷库中搬出的冰块放在排队区,______(选填“会”或“不会”)立即熔化,当冰块熔化时要______热,从而起到降温作用;喷雾降温,是因为水雾在______过程中要从周围吸收大量的热.

考点:熔化的规律及其特点汽化及汽化的特点
题型:填空题

甲、 乙、丙、丁、戊五人并排站成一排,如果甲必须站在乙的右边(甲、乙可以不相邻)那么不同的排法共有  ( )

A.24种

B.60种

C.90种

D.120种

题型:填空题

夏天的长江水浑浊不堪,是因为水流量增大,引起河床的泥沙悬浮.自来水厂取水后要除去河水中的泥沙,采用的方法是______;要除去水中的异味,可用的方法是______;若水中含有较多的______则称为硬水,通过______可以降低水的硬度.

题型:填空题

某同学作引体向上运动时,处于如图的平衡状态,两手臂和单杠的夹角均为45°已知该同学体重为60Kg,同学两手臂受到的拉力分别为(g=10m/s2)(  )

A.600N,600N

B.300

2
N,300
2
N

C.300N,300N

D.600

2N,600
2
N

题型:填空题

Kofi Annan says helping survivors of last week’’s earthquake and (1)________in the Indian Ocean is (2)________. The United Nations secretary-general says countries that have offered aid must (3)________and provide it. The offers add up to around (4)________dollars. United Nations officials say (5) ________of that is needed during the next six months.The concern about offers of international aid is (6)________. For example, the earthquake in Bam, Iran, in (7)________of 2003 killed more than (8) ________people. Countries and groups offered hundreds of millions of dollars (9) ________. The United Nations says it has (10)________only about (11)________dollars in aid received so far. Governments and organizations that offered help (12) ________that, however.On (13)________Mr. Annan met with world leaders in Jakarta, Indonesia to discuss aid for (14)________. The leaders discussed and (15)________the idea of (16)________owed by affected nations. But the leaders did not say they would do so. Some said that (17)________to survivors would be more helpful.Representatives of (18)________countries and international organizations attended the meeting in Jakarta. Officials say they will cooperate to develop (19)________ for the Indian Ocean and the (20)________.

题型:填空题

水溶性维生素摄入过多时()

A.可在体内大量贮存

B.可经尿液排出体外

C.极易引起中毒

D.通过胆汁缓慢排出体外

E.通过汗腺排出体外

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