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Scientists have traveled to the mountains of Oman to find a way to remove carbon dioxide gas from the atmosphere. 科学家们前往阿曼山寻找去除大气中的二氧化碳气体的方法。 The geologists hope to find an effective and low-cost
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By David Gollust State Department 20 April 2007 Many fear Nigeria elections will be chaotic On the eve of Nigeria's presidential election, the United States is appealing to Nigerian authorities to make the voting as free, fair and transparent as poss
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This is the VOA Special English Agriculture Report. Rice hulls, or husks, are the protective coverings on grains of rice. Rice with just its hull removed is brown rice. Rice without its hull or bran is white rice. Once rice is harvested, the hulls ar
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自然探索
Cement is a major component of concrete, the world's most widely used man-made material, an integral part of roads, bridges and buildings. But making cement requires heating limestone and other materials to very high temperatures, a process that rele
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Researchers around the world are trying to find alternative fuels to replace fossil fuels, which are finite and might not be available in sufficient quantities in coming decades to meet the growing world demand for energy. In addition, burning fossi
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