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991.
Mego Pinandito Imam Rosananto Ii Hidayat Muharyan Syamsudin Nobuo Sugimoto Ichiro Matsui Shigeru Murata Takakazu Ishii Noboru Yasuda Takao Kobayashi 《Optical Review》1998,5(4):252-256
A lidar network system consisting of two Mie scattering lidars and one differential absorption lidar was developed to measure the atmospheric environment in Jakarta. The three lidars were installed at three locations in Jakarta to study atmospheric boundary layer structure and transportation of atmospheric pollutants. The Mie scattering lidars employ compact flashlamp pumped Nd:YAG lasers operated at 1064 nm fundamental. They are installed in shelters and directed vertically. One of the Mie lidar has a rotating wedged window for scanning conically to measure wind velocity using a correlation method. The DIAL system employs two Nd:YAG laser-pumped optical parametric oscillators. The DIAL is designed to measure distribution of ozone and SO2 in the near UV region, and NO2 in the 450-nm region. The system is installed in a shelter and has a full scanning capability. 相似文献
992.
The destructive determination method of alpha emitters in various combustible solid materials has been investigated by a combination of acid digestion and coprecipitation with barium sulfate. It was consequently established that the method described in the paper may be applicable to determine alpha activities in the practical wastes. 相似文献
993.
Hideshi Nakamura Houming Wu Junichi Kobayashi Yoichi Nakamura Yasushi Ohizumi Yoshimasa Hirata 《Tetrahedron letters》1985,26(37):4517-4520
Purealin , a novel secondary metabolite, which modurates enzymic reactions of ATPases, has been isolated from the okinawan marine sponge and the structure has been determined by the 1H-1H homonuclear and 1H-13C heteronuclear NMR chemical shift correlations and CD spectra. 相似文献
994.
Solar cells are based on the photovoltaic effect of converting solar energy into electric energy. The mechanism for solar cells is divided into steps, that is, electron-hole pair generation by absorption of light in semiconductors, separation of electron-hole pairs by built-in potential, electron-hole recombination, collection of charge carriers by metal electrodes, etc. In this article, the principle and the theories of these basic steps are presented. On the basis of these steps, methods to improve the efficiency for solar cells are discussed. The fabrication process and the situation of currently produced solar cells are also presented. Solar cells having no p-n junction, that is, photoelectrochemical solar cells and MIS solar cells, are discussed from the perspective of low-cost solar cells. 相似文献
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