托福阅读真题+题目+答案：Roman and Chinese Metalworking

托福阅读真题+题目+答案：Roman and Chinese Metalworking

Chinese steel was highly valued in the Roman Empire (which controlled much of the western world between 27 B.C.E. and 476 A..), since Roman workshops could not mass-produce metals with comparable strength and sharpness. Steel is a metal alloy (mixture)manufactured by heating iron ore(raw iron)to high temperatures, then combining the molten(melted) metal with carbon or other strengthening elements. ⬛ The quality of steel produced by these techniques depends on the sustained temperature of the furnace and the quantity and condition of the added compounds. ⬛ Good-quality steel is harder than iron and has much greater flexibility and strength. ⬛ Blades made from steel therefore maintain a sharper edge for a longer time and have a greater resistance to rust than their equivalent in iron. ⬛ Western civilizations did not have sufficient knowledge of the carbon compounds that need to be added to molten iron to produce reliable steel. Instead, the Romans produced wrought iron (iron with very low carbon content) by first heating iron ore in a furnace (oven) to separate metal from impurities in a process known as smelting. This technique was used throughout the Roman Empire to make tools and bladed weapons. The resultant iron also acquired a trace of strengthening carbon from the charcoal fueling the furnaces.

1.Paragraph 1 supports all of the following statements about steel EXCEPT:

O It can be made by combining liquid iron with carbon.

O Its strength and sharpness depend on its production method.

O Its quality depends on the flexibility of the iron ore from which it is made.

O TooIs made from it remain in their original condition longer than tools made from iron do.

2.Paragraph 1 suggests which of the following about Roman metalworkers?

O They did not have furnaces that could reach high enough temperatures to melt iron.

O They lacked the technology to remove the impurities in iron ore that made iron more likely to rust.

O They were not aware that the smelting process could improve the strength of iron.

O They were not fully informed about the strengthening elements that needed to be combined with iron ore to produce high-quality steel.

The situation was different in the Chinese Han Empire(206b.c.e.220a.d., where metalworkers using more advanced furnaces had identified the natural compounds that created better-quality iron during the smelting process. Through continual practice they had refined the measurements needed to ensure that the compounds added to iron ore introduced sufficient carbon to create a reliable quality of steel. The Chinese had developed large enclosed furnaces that included bamboo nozzles (round openings) to produce steady streams of air. This made it easier to keep the fire at a steady heat and control reactions within the furnace. Chinese furnaces also burned compressed coal, which further increased temperatures and reduced fuel costs. This was significant because mass-produced cast iron (iron with carbon content greater than 2 percent)could be transformed into steel by applying blasts of cool air that provided oxygen to the molten metal (the"Hundred Refinings Method"). The Chinese also knew how to turn wrought iron into steel. Blades were wrapped in fruit skins rich in carbon containing a small amount of impurities. These packages were then sealed in clay containers and heated at high temperatures over a sustained period(up to twenty-four hours) until the metal absorbed the necessary carbon and strengthening elements. In China, these techniques were used to mass-manufacture a variety of tools, including knives, hammers, and cooking pots.

3.The word “sealed" in the passage is closest in meaning to

O moved

O arranged

O closed

O combined

4.According to paragraph 2, all of the following are true about Chinese furnaces used in steel manufacture EXCEPT:

O They used bamboo nozzles to introduce carbon to the ore.

O They could maintain stable temperatures.

O They used an efficient type of fuel.

O They could turn cast iron into steel.

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