234 resultados para F-8 aircraft Crusader


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半导体材料开放实验室基金,国家自然科学基金

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We demonstrate surface emitting distributed feedback quantum cascade lasers emitting at wavelengths from 8.1 mu m at 90 K to 8.4 mu m at 210 K. The second-order metalized grating is carefully designed using a modified coupled-mode theory and fabricated by contact lithography. The devices show single mode behavior with a side mode suppression ratio above 18 dB at all working temperatures. At 90 K, the device emits an optical power of 101 mW from the surface and 199 mW from the edge. In addition, a double-lobe far-field pattern with a separation of 2.2 degrees is obtained in the direction along the waveguide.

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Absence of gravity or microgravity influences the cellular functions of bone forming osteoblasts. The underlying mechanism, however, of cellular sensing and responding to the gravity vector is poorly understood. This work quantified the impact of vector-directional gravity on the biological responses of Ros 17/2.8 cells grown on upward-, downward- or edge-on-oriented substrates. Cell morphology and nuclear translocation, cell proliferation and the cell cycle, and cytoskeletal reorganization were found to vary significantly in the three orientations. All of the responses were duration-dependent. These results provide a new insight into understanding how osteoblasts respond to static vector-directional gravity.

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本文介绍了一种新型专用的多路电荷灵敏前置放大器,其路数最多为八路,这种电荷灵敏前置放大器采用新的设计方案,该前放主要采用低噪声场效应晶体管和集成运算放大器构成,其等效输入噪声小于等于2.2keV。该前放具有电路结构简单、体积小、输出信号上升时间快、噪声低、稳定性好等特点。并对它的设计以及特点作了较详细的阐述。

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IEECAS SKLLQG

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IEECAS SKLLQG