单词：cold stratification
单词：cold stratification 相关文章
In 1940, North American Aviation designed the legendary P-51 Mustang in response to the British need for a high-performance fighter aircraft. The Mustang featured the most advanced laminar flow wing and a ducted cooling radiator positioned under the
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Two pilots recently set a new altitude world record for gliders. A glider is an aircraft that does not have an engine. They are pulled into the air by powered airplanes and then released. They are designed to ride warm, rising air to gain altitude. T
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Iron Dome defense system uses cameras and radar to track incoming rockets and can shoot them down within seconds of their launch. The system was developed by Rafael, the Israel Military Industries, at a cost of $200 million. Robert Berger | Jerusalem
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U-2 Spy Plane Still Flying High One of the oldest planes the United States Air Force still flies is used to carry out some of America's most sensitive and critical missions. Whether it's aiding NATO troops in Afghanistan, providing surveillance over
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年底啦，如果你在计划过年去哪儿玩或是明年的出国游，不如看看权威旅游刊物Lonely Planet推荐的2017年十大旅游目的国！这些地方，好玩儿、人少、又不贵！跟Jenny, Spencer一起体验吧！ 关键词：
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Chinese Academy of Sciences successfully launched a new sounding rocket, Kunpeng-1B, in Hainan Danzhou early Wednesday. The rocket reached a flight height of 300 kilometers for the first time. Its arrow configuration of altitude control system and ca
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