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排序方式: 共有1041条查询结果,搜索用时 15 毫秒
941.
The object of this paper is to describe some typical sections of theTriassic Chinglung limestone (青龙石灰岩) in the Lower Yangtze Valleyso that sections in other parts of South China may be compared, both asto stratigraphy and as to fauna, with that of the type area. The name, 相似文献
942.
The senior author has, since several years,~1 pointed out the high magnesian content in the upper Wutai formation in which frequently occur 相似文献
943.
C. Y. HSIEH 《地质学报》1942,(Z2):273-287
正 I. INTRODUCTION Iron deposits are widely distributed in western Kueichou. From the economic standpoint, only two or possibly three of them deserve special attention, and these are the Kuanyinshan deposit of Shuicheng,' the Tiehkuangshan and Tsaiyuantse 相似文献
944.
945.
一、引言 自1985年初以来,一个新的半球谱模式已在法国气象局的CRAY—Ⅰ计算机上业务化运行了。这个模式的目标是提供直到4天的准确的预报产品。尽管这个模式已经完成了它的任务,但还有几个问题必须逐步解决;热带附近的预报场和分析场之间的误差,由于变量从分析高度到模式高度来回插值引起的初始震荡以及在物理过程参数化中出现的缺陷,有关修改已在模式中采用并证明是有效的。这项工作很容易用纬向平均诊断的方法来做。这种诊断对于指出模式的缺陷和检验它们的订正是有用的工具。 相似文献
946.
A DECADE OF MARINE PHYTOPLANKTON RESEARCH IN CHINA 总被引:1,自引:0,他引:1
A brief account is given of the progress of marine phyto-plankton research in the People's Republic of China for the last ten years. Most of these studies have been carried out, particularly before 1957, in close connection with investigations on fishing grounds and sea-farming inshore waters. During the last two years the progress of marine phyto-plankton research has been especially rapid and the area investigated has been greatly enlarged in pace with the comprehensive oceanographic investigation of the four seas, Peihai, Yellow Sea, East China Sea and South China Sea. 相似文献
947.
Coal Oil Point (COP) is a natural oil seep off the coast of Santa Barbara, California. Although most studies examining the fate and effects of petroleum have focused upon urbanized or anthropogenic sources of inputs, few have examined the effects of polyaromatic hydrocarbons (PAHs) derived from natural seeps. In order to evaluate the effects of PAHs derived from COP on marine fish populations, hatchery-reared California Halibut (Platichthys californicus) were exposed for 30 days to seven dilutions of sediments collected from COP. Hepatic cytochrome P450 1A (CYP1A), biliary fluorescent aromatic compounds (FACs), gonadal somatic indices, and plasma steroid concentrations. Sixteen USEPA priority PAHs were targeted for analysis in each sediment dilution. In general, biochemical responses were somewhat recalcitrant to dose-response relationships and were less sensitive than the literature values established for the same indicators following exposure to urbanized PAHs. Trends toward reductions in plasma 17beta-estradiol concentrations were observed, but reductions in gonadal somatic indices were not observed. FAC values for naphthalene, benzo(a)pyrene, phenanthrene-related compounds reached maximums at 33-100% COP sediment. The resulting insensitivity may be unique for exposure to "natural" petroleum due to a higher concentration of lower molecular weight PAHs or uncharacterized inhibitors. 相似文献
948.
Shellfish samples were collected from seven inter-tidal and two sub-tidal sites between 23 May and 8 June 1999 in Vancouver Harbour and were analysed for paralytic shellfish poisoning (PSP) using a mouse bioassay. PSP was detected in mussels collected at four sampling sites in English Bay and Burrard Inlet, at a concentration below 20 microg saxitoxin equivalents (STXeq)/100 g wet weight. 相似文献
950.