主要根据据分子大小进行物质分离的方法是() A.聚酰胺色谱法 B.凝胶过滤法 C.离

题型:单项选择题 B型题

问题:

主要根据据分子大小进行物质分离的方法是()

A.聚酰胺色谱法

B.凝胶过滤法

C.离子交换法

D.硅胶柱色谱法

E.纸色谱法

考点:中药执业药师中药学专业知识(二)2007年执业中药师专业知识二考试真题
题型:单项选择题 B型题
设两点A(3,1),B(-1,5),直线l通过线段AB的中点C.
(1)若l⊥AB,求直线l的倾斜角的大小;
(2)若l的倾斜角θ满足sinθ=
2
5
,求l的方程.
题型:单项选择题 B型题

下列变化中一定都属于化学变化的一组是(  )

A.瓷碗破碎,干冰升华

B.煤气燃烧,胆矾研碎

C.白磷自燃,菜刀生锈

D.铁制成铁锅,铁矿石炼铁

题型:单项选择题 B型题

下面描述的特性中,与高羊茅相符的是()

A、修剪高度通常在3cm以上

B、抗逆性较强

C、叶片质地粗糙

D、常用于高尔夫球场果岭

E、耐粗放管理

题型:单项选择题 B型题

营业厅信息安全的要求包括哪些?

题型:单项选择题 B型题

The "standard of living" of any country means the average person’s share of the goods and services which the country produces. A country’s standard of living, (1) , depends first and (2) on its capacity to produce wealth." Wealth" in this sense is not money, for we do not live on money (3) on things that money can buy. "Goods" such as food and clothing, and "services" such as transport and " (4) ". A country’s capacity to produce wealth depends upon many factors, most of (5) have an effect on one another. Wealth depends (6) a great extent upon a country’s natural resources. Some regions of the world are well supplied with coal and minerals, and have a fertile soil and a (7) climate; other regions possess none of them.

Next to natural resources (8) the ability to turn them to use. China is perhaps as well (9) as the USA in natural resources, but suffered for many years from civil and (10) wars, and (11) this and other reasons was (12) to develop her resources. (13) and stable political conditions, and (14) from foreign invasion, enable a country to develop its natural resources peacefully and steadily, and to produce more wealth than another country equally well (15) by nature but less well ordered.

A country’s standard of living does not only depend upon the wealth that is produced and consumed (16) its own borders, but also upon what is indirectly produced through international trade. (17) , Britain’s wealth in foodstuffs and other agricultural products would be much less if she had to depend only on (18) grown at home. Trade makes it possible for her surplus manufactured goods to be traded abroad for the agricultural products that would (19) be lacking. A country’s wealth is, therefore, much influenced by its manufacturing capacity, (20) that other countries can be found ready to accept its manufactures.

20()

A.provided

B.depended

C.given

D.supposed

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