The development of a scientific approach to chemistry was, however, hampered by several factors. The most serious problem was the vast range of material available and the consequent difficulty of organizing it into some system. In addition, there 'were social and intellectual difficulties, chemistry is nothing if not practical, those who practice it must use their hands, they must have a certain practical flair. Yet in many ancient civilizations, practical tasks were primarily the province of a slave population. The thinker or philosopher stood apart from this mundane world, where the practical arts appeared to lack any intellectual content or interest.
The final problem for early chemical science was the element of secrecy. Experts in specific trades had developed their own techniques and guarded their knowledge to prevent others from stealing their livelihood. Another factor that contributed to secrecy was the esoteric nature of the knowledge of alchemists, who were trying to transform. base metals into gold or were concerned with the hunt for the elixir that would bestow the blessing of eternal life. In one sense, the second of these was the more serious impediment because the records of the chemical processes that early alchemists had discovered were often written down in symbolic language intelligible to very few or in symbols that were purposely obscure.
What is the passage mainly about?
A.The scientific revolution in the seventeenth century.
B.Reasons that chemistry developed slowly as a science.
C.The practical aspects of chemistry.
D.Difficulties of organizing chemical knowledge systematically.
第2题
A.支气管扩张
B.肺炎
C.慢性支气管炎继发感染
D.肺结核
E.肺化脓症
第3题
A.痰中带血
B.少量咯血
C.中等量咯血
D.大量咯血
E.不能确定,需进一步评估
第4题
A.慢性支气管炎
B.间质性肺炎
C.支气管扩张
D.肺结核
E.大叶性肺炎
第5题
A.慢性支气管炎
B.间质性肺炎
C.支气管扩张
D.肺结核
E.大叶性肺炎
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