专业英语课件chapter1.ppt

另一个原理是，即使反应是有利的，产物的能量比起始物质低，混乱度比起始物质大，反应也不一定必须进行得很快。 * 最后的一个例子反映了另一条有关的原理：即使反应以低能量的产物为终止，仍需要一些额外的能量以便通过不稳定的过渡阶段。 * 事实上，人类的每项活动都用到一些由化学提供或加工的物质，同时在许多活动中也包含着化学变化。 * 1995年，这一年中在世界范围内，化学家创造了100万种以上的新化合物。这个步伐还在加快。有些新分子正在考察作为新药物的可能性（参看第2章），另外一些则被用于制造新材料，如有用的塑料等。 * 新近发明的化学反应用于生产药用化合物和其他化学物质时常常使效率更高。 * 一些化学家在从事新分子的创造性的合成工作，一些化学家献身于测定新发现的或新合成的化学物质的详细结构。 * 生物化学和分子生物学处于药学和生物学的边缘。现在科学家正在从事揭示生命与疾病的化学工作。利用这些信息，药物化学家可以设计新的药物 * 另外一些化学家在做环境方面的工作，研究正在发生些什么（例如，使臭氧产生空洞的化学反应）和探索如何使制造过程有利于环境。 * 开发这类过程是化学和制药工业的主要方向，他们曾发誓要使现代工业充分地考虑环境，而成为“绿色化学”的一部分。例如，在Tennessee有一个新的化学工厂，它放回河中的水竟比它取用时还洁净。 * In 1995, more than one million new chemicals were created worldwide by chemists. The pace is accelerating. Some of the new molecules are examined as possible new medicine, and others are used to make new materials such as useful plastics. 1.7 How large a field is chemistry? Newly invented chemical reactions are often applied to manufacture pharmaceutical compounds and other chemicals more efficiently. 1.7 How large a field is chemistry? Some chemists are involved in the creative synthesis of new molecules, some chemists devote themselves to determining the detailed structures of newly discovered or newly created chemicals. 1.7 How large a field is chemistry? Biochemistry and molecular biology are on the borderline with medicine and biology. Here scientists work to unravel the chemistry of life and disease. With this information , medicinal chemists can design new medicines. 1.7 How large a field is chemistry? Other chemists work on the environment, studying what is happening (e.g., the chemical reactions that have caused the creation of the ozone hole) and learning how to make manufacturing processes environmentally friendly. 1.7 How large a field is chemistry? Developing such process is a major activity in the chemical and pharmaceutical industries, which have pledged to see that modern manufacturing fully respects the environment as part of “green chemistry”. For example, a new chemical pl