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921.
The analytical results of the previous paper(Wu,1989)are used to study the properties of vertical veloc-ity distribution at the top of the boundary layer.The relative position of a jet like geostrophic flow and el-lipse-shaped orography will affect the characteristic feature of vertical motion at the top of the boundary layerwhen the contributions of friction and orography are taken into consideration simultaneously. 相似文献
922.
923.
我国沿海近岸带水域的悬沙分布特征 总被引:4,自引:1,他引:3
本文根据实测悬沙资料,阐述了我国沿海近岸带水域的悬沙浓度由黄河口和长江口-杭州湾为中心,分别向南、北递减,高低相间,构成波状起伏的分布特征,同时分析了径流输沙、潮流、波浪、海岸类型诸要素在悬沙浓度时空变化中的不同作用. 相似文献
924.
925.
Jiehao Huang Qiusheng Gu Hongjun Su Zhaohui Shang 《Astrophysics and Space Science》1996,235(1):109-116
We report on a new ESB source, as defined by Allenet al. (1991), with Wolf-Rayet (WR) bands in its optical spectrum. The WR bump at 4605-4686 is detected. The bump consists of broad HeII 4686, NV4605-4619, NIII4634-41, and possibly, CIII4647-52 emission. The narrow nebular lines are clearly discernable on our spectrum. The number of WR stars derived from the luminosity of HeII4686 is about 8100. The oxygen abundance is about 9.06×10–4, greater than the solar value. 相似文献
926.
An experimental study was carried out on a granitic mylonite (La Bresse, France) to analyze the influence of pore microstructure on transport properties. Different crack networks were obtained by a controlled thermal treatment. Microstructures were analyzed by means of gas adsorption and mercury porosimetry. Transport properties have been investigated by measuring gas permeability and electrical conductivity. The dependence of permeability on confining pressure shows an exponential decrease, characteristic of a porosity made of cracks. Correlations between measured parameters have been analyzed by comparing them with relations deduced from theoretical models. Linking the formation factor to the porosity leads to a rather low tortuosity value (about 2.4), characterizing a medium with a well connected porosity. Correlation between permeabilityk and formation factorF leads to a power-law relationk F
–n
wheren2.9, which is consistent with a crack model describing the behavior of the thermally treated rock. 相似文献
927.
GUO HUA FAN TONG QI YAO KE LI HAN KE JIA ZHU ZUO WEN GU Institute of Geophysics China Seismological Bureau Beijing China 《地震学报(英文版)》1998,11(6):719-727
ntroductionThevariationmagneticfieldoftheEarthcontainsabundantinformation,suchastheinformationrelativetosolaractivity,solarte... 相似文献
928.
Grey characteristics of microbanding of stalagmite in Shihua Cave, Beijing and its climatic signification(I) 总被引:2,自引:0,他引:2
Xiaoguang Qin Dongsheng Liu Ming Tan Tieying Li Jinpo Lü Zhaoyan Gu Houyuan Lü Zhongli Ding Zhengtang Guo Jiaqi Liu Gaozhong Nie 《中国科学D辑(英文版)》1998,41(2):151-157
Grey microstructure of microbanding in thin sections of stalagmite T9501 from Shihua Cave, Beijing was studied. The types
of grey and the morphologic features of organic material were classified. The signification of microbanding and annual layer
was discussed. The standard distinguishing the false annual layer and the multi-year layer is set up, which provides the theoretic
fundaments for paleoclimatic study.
Project supported by the National Natural Science Foundation of China (Grant No. 49672134). 相似文献
929.
Lianhong Gu 《Boundary-Layer Meteorology》1998,87(3):515-524
This paper considers a modification to the localized near-field (LNF) theory for predicting scalar concentrations from source distributions in plant canopies. It is argued that the non-diffusive, near-field part of the transition probability Pn, and thus the near-field contribution of the scalar concentration Cn, in the original theory are simply errors. The (approximate) equality of the sum of Cn and the diffusive, far-field contribution Cf with the total scalar concentration C is not guaranteed in general by this theory. A revision is suggested. 相似文献
930.