tpo9
Both
ofthe professor and the writer explore the issue about whether hydrogen based fuel engine has advantages over the internal combustion engine for cars. The author lists three aspects of advantages to support that the hydrogen based fuel engine is a good solution. The speaker, on the contrary, insists that the writer is too optimistic in the hydrogen based engine because hydrogen is not the solution.
First, hydrogen is not as easily available as the writer described in the passage, claims the professor, its common present -water- is not the usable form of hydrogen to produce energy. The energy can only be produced through the pure liquid state of hydrogen, which is a highly artificial process. Besides, it is difficult to produce and store, which has to be kept in extremely cold environment that is -253 Degree Celsius
听的好细节啊. Imagine how complex the technology could be, the fuel cell engine is not that practical and hydrogen is also not an easy approached substance. Therefore, this disproves its counterpart in the reading directly.
Moreover, the speaker declares that hydrogen is not the solution to the pollution problem. He explains that producing the pure hydrogen creates pollution. Purification technology is required to generate pure hydrogen, which needs energy that is provided by the burning of coals and oil. Accordingly, although cars are not the origin of pollution, the factories produce pure hydrogen are. Consequently, this is another place where experiences the contradicted theory.
At last, the lecturer asserts that hydrogen based fuel cell engine does not cost less. The reason is that platum, a kind of rare and expensive metal, is required in this engine. Without that the hydrogen cannot go through the process of chemical reaction in order to produce energy. Furthermore, the replacement of another cheaper material has so far been unsuccessful. Accordingly, the last point is rebutted.
In conclusion, the professor clearly identifies the weaknesses in the passage and convincingly shows that the central argument in the reading, the advantage of hydrogen based fuel cell engine overweighs that of internal combustion engine, is incorrect.
哈哈,其实每段后面总结我也抄别人的
-- by 会员 qianjun06 (2012/7/20 8:05:13)