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401.
Chen Cao Hong Wu Jian-Ling Wang Cai-Na Hao Zu-Gan Deng Xiao-Yang Xia Zhen-Long Zou National Astronomical Observatories Chinese Academy of Sciences Beijing Graduate School of Chinese Academy of Sciences Beijing College of Physical Sciences Graduate School of Chinese Academy of Sciences Beijing Department of Physics Tianjin Normal University Tianjin 《中国天文和天体物理学报》2006,6(2):197-209
We selected a sample of luminous infrared galaxies by cross-identification of the Faint Source Catalogue (FSC) and Point Source Catalogue (PSC) of the IRAS Survey with the Second Data Release of the SDSS. The size of our sample is 1267 for FSC and 427 for PSC by using the 2σ significance level cross-section. The "likelihood ratio" method is used to estimate the individual's reliability and for defining two more reliable subsamples (908 for FSC and 356 for PSC). A catalog of infrared, optical and radio data is compiled and will be used in further work. Some statistical results show that luminous infrared galaxies are quite different from ultra-luminous infrared galaxies. The AGN fractions of galaxies at different infrared luminosities and the radio-infrared correlations are consistent with the previous studies. 相似文献
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手持式激光测距仪前级接收通道的相关问题研究 总被引:2,自引:0,他引:2
夏界宁 《大地测量与地球动力学》2007,27(Z1):93-95
介绍了手持式激光测距仪前置放大电路的设计方法,并且针对便携式设备供电的特殊性,给出了单电源供电放大电路的解决方案,较好地解决了前级接收通道电路设计的相关问题. 相似文献
405.
Steel piles at the tidal zone can be seriously corroded. Common protective methods such as painting or coating with rubber
or other protective materials, etc. cannot provide full protection when used as supplementary protection because these traditional
methods require strict pretreatment and sealing of the metallic surface from the corrosive mediums, and time for the protective
coatings to solidify. This is very difficult under the severe action of waves and surges on the sea.
With our oil-soluble DZ-2 tape, protection efficiency for hanging steel plates at the tidal and splash zones reaches to 82–99%.
The protection efficiency of water soluble DZ tape at the tidal zone reaches to 92.9%. The DZ and DZ-2 tapes can rapidly reduce
the original corrosion velocity to ten percent and one percent respectively as fully proved by the 500 hour rapid corrosion
testing with indoor salt fog and by the relevant electrochemical parameters of instantaneous corrosion velocity, etc.
DZ tape absorbs much OH− to cause a pH rise. A synergistic protective effect is gained when DZ tape is used together with cathodic protection of steel
piles at the tidal zone. The working principle of DZ tape is different from that of DZ-2 tape even though they are composed
of the same chemical materials. The latter provides protection because of the close affinity between metal and its carboxyl
group shields the active centre at the metal surface to reduce the activation energy of metal. The carbon chain forms a covering
oil film of netted structure.
Dai Tao, Dai Wei and Xia Caiyuan et al. participated in the research and made useful contribution. Contribution No. 1656 from
the Institute of Oceanology, Academia Sinica. 相似文献
406.
西北地区土壤资源特征及其开发利用与保护 总被引:10,自引:8,他引:2
在分析西北地区土壤分布规律的基础上,研究了不同类型区土壤的资源特征及其在开发利用中存在的问题,认为黄土地区土壤土质疏松、粉砂含量高、富含碳酸钙是水土流失的物质基础;干旱区广为分布的荒漠土壤资源的性能低劣、绿洲区水土资源的利用比例失调是造成土地荒漠化、土壤盐渍化的根本原因;而高原土壤的粗骨性、土层浅薄、有效肥力低则加速了草场的退化和沙漠化.提出了西北地区土壤资源的合理利用与生态环境保护相协调的途经,即搞好农田基本建设,采用旱作技术节水和合理用水,扩大林草植被,保护天然草场和林木.并认为西北土壤资源的开发利用要在充分发挥其生产潜力的同时,首先应遵循生态规律,开发与保护并重,防止土壤资源衰竭和破坏. 相似文献
407.
A morphological study of a marine red alga from China, previously identified by various authors as “Solieria mollis (Harv.) Kylin”, has been shown to be an undescribed species ofSolieria. The present new speciesSolieria tenuis is characterized by the slender branches, the unbranched and nonseptate connecting filament and the discoid holdfast surrounded
by prop branches resembling proproots of land plants.
Contribution No. 989 from the Institute of Oceanology, Academia Sinica. 相似文献
408.
Wu Chaoyuan Li Jiajun Xia Enzhan Peng Zhuosheng Tan Shuzhi Li Jun Wen Zongcun Huang Xiaohang Cai Zulin Chen Guojun 《中国海洋湖沼学报》1989,7(4):327-334
A 2-year study onKappaphycus alvarezii (Doty) Doty introduced to Hainan Island from the Philippines in 1985 showed promising results. The average daily growth in
weight reached 10% at a favourable temperature of about 26°C. Experimental results showed that timely cutting of the plant
was an effective way to obtain new cuttings for cultivation and accelerate growth. New cuttings 0.05 kg in weight are suggested
to be used as “seeds” and the old plant should be harvested. At present, artificial cultivation with a type of underwater
raft applicable in places where there is strong wind will expand cultivation to more regions in Hainan Province.
This paper was originally published in Chinese inOceanologia et Limnologia Sinica
19(5): 410–418, 1988. The plant under discussion wasEucheuma alvarezii Doty which was previously calledE. striatum in the article, and which now becomesKappaphycus alvarezii (Doty) Doty. To the original title, “in China” was added. Only the essence of the original article was presented. 相似文献
409.
410.
XPer的新发射相:光谱与红外观测 总被引:1,自引:0,他引:1
XPer的新发射相:光谱与红外观测杭恒荣,夏剑萍中国科学院紫金山天文台,南京210008中国科学院光学天文联合实验室关键词Be星/X射线双星,发射线,JHK测光1引言XPer是一颗Be/X射线双星(4U0352+30)的光学对应体[1-3],中子星的... 相似文献