问题 单项选择题

难溶性药物在表面活性剂的作用下溶解度增加的现象称为()

A.絮凝

B.增溶

C.助溶

D.潜溶

E.盐析

答案

参考答案:B

解析:增溶是指难溶性药物在表面活性剂的作用下,在溶剂中增加溶解度并形成溶液的过程。难溶性药物与加入的第三种物质在溶剂中形成可溶性分子间的络合物、缔合物或复盐等,以增加药物在溶剂中的溶解度。这第三种物质称为助溶剂。助溶剂多为某些有机酸及其盐类如苯甲酸、碘化钾等。潜溶剂系指能形成氢键以增加难溶性药物溶解度的混合溶剂。能与水形成潜溶剂的有乙醇、丙二醇、甘油、聚乙二醇等。

单项选择题

Questions 61—65 are based on Passage Two:Passage TwoAs the 21st century begins, a number of leaders in politics, education, and other professions believe that the US must adopt some new values to go along with the old traditional ones. What new values should Americans adopt This is a very difficult question to answer. Certainly, a greater value should be placed on the conservation of natural reasources; Americans should learn to use less and waste less. But conservation has never been a p value to Americans, who have believed that their country offered an endless,abundant supply of natural resources.Recently, progress has been made—more and more Americans are recycling their paper,cans,bottles,and other goods—but old wasteful habits died hard. Furthermore,the need to protect the environment may conflict with the need for jobs,as in the Northwest ,where conservationists battle lumber companies that want to cut down ancient redwood trees. A belief in the value of conservation is still compared with other American values; it can become per only as Americans see the need for it more clearly.In addition,Americans may need to place a p value on cooperation on a national scale to achieve important national objectives. The American idea of the national good has never been based on national cooperation but rather on the freedom of the individual, maintaining those conditions that provide the greatest freedom and prosperity for the individual . It is far more difficult for Americans to accept shared sacrifice for the common good and wellbeing of the entire country. For example ,although the majority of Americans believe that it is extremely important to balance the national budget and reduce the deficit, they do not want to see cuts in government programs that benefit them personally.The American value of competition also hinders the development of a spirit of national cooperation. Competition sometimes encourages feelings of suspicion rather than the mutual trust that is necessary for successful national cooperation.Although Americans often cooperate successfully on the local level—in neighborhood groups and churches, for example, on the national level, they may see themselves as part of an interest group that is competing with other interest groups for government funds. A request by the national government for shared sacrifice may be seen as coercive and destructive rather than voluntary and constructive. However, the demands for the 21st century may compel Americans to place a greater value on national cooperation to solve problems that affect them all, directly and indirectly.

The value of competition works against the spirit of national cooperation in that ().

A.it makes people not believe in the government

B.it causes people to suspect but not to trust each other

C.it makes people even unable to cooperate well on local levels

D.it encourages people to gain success through individual hard work

单项选择题 A1/A2型题