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滇中地区元古代沉积盆地演化及动力学初探 总被引：5，自引：0，他引：5
滇中地区是扬子地台元古宙地层发育的典型地区,包括云南东川、罗（茨）武（定）、易门、元江４个区段。早元古代地层为大红山群,其与太古代底巴都组为角度不整合接触。中元古代地层为昆阳群,晚元古界包括青白口系和震旦系,其中中元古代昆阳群按“倒层”观点分为下亚群... 相似文献
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This study was performed in order to assess whether bisphenol (BPA) and diethylstilbestrol (DES) had agonistic or antagonistic effects on oocyte maturation using marine fish. We tested the effects of these chemicals on in vitro maturation, germinal vesicle breakdown (GVBD), assay using oocytes from the longchin goby, Chasmichthys dolichognathus. During the maturation process, low concentrations of BPA and DES triggered GVBD depending on the stage of oocyte development; BPA at 0.044 nM and DES at 0.037, 0.37, and 3.73 nM induced GVBD in 0.82-0.88 mm diameter oocytes (germinal vesicle located near the center of oocytes). In 0.76-0.80 mm diameter oocytes (fully vitellogenic oocytes), BPA induced GVBD at relatively higher concentrations (4.38, 43.8, and 438 nM). In 0.86-0.90 mm diameter oocytes, BPA and DES had no observable effect on GVBD at the concentrations tested. Oocytes with diameters between 0.82 and 0.88 mm appeared to be more sensitive to these chemicals. Moreover, our results showed that BPA and DES did not inhibit GVBD. 相似文献
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The aims of the present study were to investigate the effects of mariculture activities on inorganic mercury (Hg(2+)) adsorption/desorption on sediments and the distributions of newly adsorbed Hg(2+) on different chemical fractionations. The adsorption amount and binding energy of Hg(2+) on mariculture sediment (MS) were significantly higher (p<0.05) than reference sediment (RS). This may be explained by the strong complexation role that exists between Hg(2+) and organic matter (OM), which derived from unconsumed fish feed and fish metabolites. The reducible Hg(2+) in MS was significantly lower (p<0.01) than RS, which may have been caused by the decreasing amount of iron and manganese hydroxide in MS, lead to the decrease of Hg(2+) bound to them. On the contrary, the residual Hg(2+) was significantly higher (p<0.01) in MS than RS, which suggests that newly adsorbed Hg(2+) was more stable in MS than RS. 相似文献
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本文就如何提高地矿科技查新质量进行了三方面的探讨：首先阐述了文献检索“查全率”和“查准率”的具体措施；然后论述了地矿各类查新成果新颖性判别与其结论关系；最后提出查新工作中存在的问题与其对应的对策。 相似文献
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海沟中沉积充填物的几何形态总是趋向于动力平衡的，所以这个平衡系统没有沉积物的净输入或输出，假设在一个稳定态的海沟楔几何形态的情况下，如何其它的控制参数是已知的话，沉积速率和俯冲速率这些未知参数是能够被确定的。 相似文献
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滇中地区中元古代昆阳群落雪组叠层石礁的新发现及其意义 总被引：4，自引：0，他引：4
滇中地区中元古代昆阳群落雪组主要由白云岩组成,内含较多的硅质纹带、条带和团块。该白云岩以含叠层石为特色,叠层石包括Ｓｔｒａｔｉｆｅｒａｕｎｄａｔａ,Ｓ．ｂｉｗａｂｉｋｅｎｓｉｓ,Ｃｒｙｐｔｏｚｏｏｎｈａｐｌｕｍ,Ｃ．ｇｉｇａｎｔｅｕｍ,Ｃ．ｈａｐｌｕｍ,Ｃ．ｇｉｇａｎｔｅｕｍ,Ｋｕｓｓｉｅｌｌａｋｕｓｓｉｅｎｓｉｓ,Ｇｒｕｎｅｒｉａｓｉｎｅｎｓｉｓ,Ｎｕｃｌｅｅｌｌａ,Ｌｉｎｏｃｏｌｌｅｎｉａｘｉａｏｘｉｎｃｈａｎｇｅｎｓｉｓ,Ｇａｏｙｕｚｈｕａｎｇｉａｄｅｐｒｅｓｓａ等,还有较多纹层状叠层石。… 相似文献
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滇中中元古代昆阳群因民组碎屑风暴岩及其意义 总被引：16，自引：1，他引：15
滇中地区中元古代昆阳群因民组以碎屑岩为主,内发育典型的风暴沉积构造 (包括渠铸型、丘状交错层理和洼状交错层理、递变层理等 )。风暴沉积主要包括 4种岩相类型 :A -具口袋构造的递变层理砂岩段。B -具丘状或洼状交错层理的砂岩段。C -具均质层理的粉砂岩、泥质岩段。D -具水平层理的泥质岩段。上述岩相A、B、C分别代表风暴流作用 -风暴浪作用 -风暴后期的快速悬浮沉积 (事件沉积 ),D代表风暴过后缓慢悬浮沉积 (背景沉积 ),它们组合成不同的风暴沉积序列。滇中地区昆阳群风暴沉积的发现表明中元古代大气圈、水圈及其相互作用与现今近似;中元古代滇中地区位于低纬度 (5 - 30°)的风暴作用带。该沉积对于解释因民组递变层砂岩的成因、证实昆阳群的地层层序也具有重要意义。 相似文献