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- The characteristic parameters for dusty plasmas of rocket exhaust plume and polar mesosphere are estimated and analyzed based on their practical data. 对火箭喷焰和地球极区中层大气尘埃等离子体的特征参量做了定量估计和分析。
- Polar Mesosphere Summer Echoes (PMSE) 极区中层夏季回波
- Hall, C. 1988: fist observations of summer polar mesospheric backscatter with a 224 MHz radar, Geophys. Res. Lett., 15, 18-31. 采用224兆赫雷达首次测得的夏季极地中间层大气的后向散射。“地球物理研究通讯”，第15卷28-31页。
- The two systems of government are polar opposites. 这两种政体正好相反。
- Neutral air turbulence and temperatures in the vicinity of polar mesosphere summer echoes 极地中层夏季回波附近中性大气湍流和温度
- STATISTICAL CHARACTERISTICS OF INERTIAL GRAVITY WAVES OBSERVED BY VHF RADAR IN THE POLAR MESOSPHERE 极区中层惯性重力波VHF雷达观测的统计特征
- Usually occurring at high latitudes in summer months, the diaphanous apparitions are also known as [url="]polar mesospheric clouds[/url] and may be connected to global change in the lower atmosphere. 夜光云通常出现在夏季的高纬度地区，这半透明的神奇现象也叫做极地中层云，可能与低层大气的全球变化有关。
- Seasonal variations of the Na and Fe layers at the South Pole and their implications for the chemistry and general circulation of the polar mesosphere 南极纳和铁层的季节性变化和它们对极地中层化学和大气环流的含义
- Most insect do not live in polar region. 大多数的昆虫不在极地地区生存。
- Are there any animals in the polar circles? 南极圈和北极圈内有动物存在吗？
- Polar mesosphere summer echoes 极区中层夏季回波
- polar mesosphere 极区中层大气
- Located or found in one of the Polar Regions. 环极的，围绕极地的位于或发现于一个极地区域中的
- In spite of vigilance a polar bear escape from the zoo. 尽管警戒很严，北极熊还是逃出了动物园。
- The polar region is the habitat of the polar bear. 北极地带为北极熊的栖息地。
- Although they can swim, the polar bears are terrestrial animals. 北极熊虽然会游泳，但也是陆栖动物。
- In spite of vigilance a polar bear escaped from the zoo. 尽管警戒很严，北极熊还是逃出了动物园。
- The polar bear's habitat is the icy waters of the Arctic. 北极熊的栖息地是冰冷的北极海域。
- Love and hatred are polar feelings. 爱与恨是完全相反的感情。
- Extending across or crossing either of the Polar Regions. 横越极地任一个横越或穿过两个极地地区中的
