排序方式: 共有32条查询结果,搜索用时 19 毫秒
1.
3.
4.
锶,硼和氟联合作用的亚急性毒理实验及环境意义 总被引:1,自引:0,他引:1
本文以自由饮水给药方式进行了锶、硼和氟联合作用的亚急性实验,以探讨锶、硼对氟的拮抗作用。实验结果,给予小鼠200×l0^-6 F 六个月后,可使其骨氟含量显著升高(P<0.01),肾碱性磷酸酶活力(ALP)显著增高(P<0.01),4、5个月后血清碱性磷酸酶(ALP)活力亦显著增高(P<0.O1),同时给予80×l0^-1 B3+、100×l0^-6Sr2+ 时,可以显著降低骨氟含量,抑制血清、肾碱性磷酸酶的活力,表明锶与硼对氟存在拮抗作用。 相似文献
5.
6.
瓦窑堡煤系有机岩石学特征及煤成烃潜力研究 总被引:3,自引:0,他引:3
瓦窑堡煤系是我国重要的含煤岩系之一,陆相生油的观点最早可能源于瓦窑堡煤系含油性特征。通过对瓦窑堡煤系煤和暗色泥岩有机质的显微岩石学和宏观煤岩学特征的分析,提出了瓦窑堡煤系煤主要形成于深覆水森林泥炭沼泽相,类脂组含量高,且镜质组的主要类型为富氢的基质镜质体,有机地球化学结果表明瓦窑堡煤系煤具有Ⅱ型有机质的特征,处于低熟-成熟阶段,热模拟实验证明其具有良好的油气生成潜力。但由于瓦窑堡煤系规模小,煤层厚度薄,煤系泥岩有机质类型偏差,且煤中主要生油显微组分尚末进入大量生油期,因此难以形成油藏。 相似文献
7.
Six elemental groups in the gold deposits in the study region have been distinguished:( 1 ) tungsten-antimony-gold; (2) tungsten-gold; (3) antimony-gold; (4) lead-zinosilvergold; (5) uranium-silver-gold; (6) simple gold. Discussed in the present paper are the distribution, source, mineralization, migration and concentration of gold. The resuhs show that the ore-controlling strata or source beds related to gold deposits all show high background values of gold; the gold and other associated ore-forming dements are obviously derived from the country rocks. Mineralization is related chiefly to regional metamorphism in the ore-controlling strata, or alkali-pervasing metasomatism. During metamorphism in the orecontrolling strata, gold was released into solutions, and then transported and deposited in some localities. Gold carried in hydrothermal solutions occurs mainly in the form of Na[Au(SH)2]. Native gold or electrum were precipitated from the ore solutions and concen.trated into ore deposits with the decrease of T, pH and fO2. 相似文献
8.
9.
华南花岗岩类中金的丰度 总被引:2,自引:0,他引:2
Gold abundances iu granitic rocks of differeat geological periods of Southern China were estimated. A review of the quantitave data now availabe indicates that unaltered granitic rocks have a rather restricted range in gold content, rarely exceeding 4 ppb and generally range from 1.4 to 3.3 ppb.Mean gold content tends to decrease from basic to acid granitoids. This tendency suggests that gold is not concentrated in the residual silieate melt during the formation of granitic rocks. Abundance dtata for granitoids in Southern China provide no geochemical clues or guides to distinguish areas favorable or unfavorable for gold mineralization, but they are necessary to establish background values for various rock types. 相似文献
10.