硬玉和软玉的区别     

《西部资源》2013,(4):69

硬玉即翡翠,是由一种钢和铝的硅酸盐矿物组成,纯净者无色或白色.其块体的化学成分为:二氧化硅占58.28％,氧化钠占13.94％,氧化钙占1.62％,氧化镁占0.91％,三氧化二铁占0.64％,此外还含有微量的铬、镍等.其中,铬是使翡翠具有翠绿色的主要因素.通常翡翠含氧化铬0.2～0.5％,个别达2～3.75％以上.  相似文献   

Study of the Factors Affecting the Abundance of Organic Matter in Jurassic Carbonate Rocks in Qiangtang Basin, Tibet     

文志刚  胡明毅  龚文平  肖传桃 《中国地球化学学报》2004,23(1):52-56

Field and laboratory analyses of carbonate rock samples from the Qiangtang Basin,Tibet, indicate that carbonate source rocks are mainly developed in the Middle Jurassic Xiali Formation and Upper Jurassic Suowa Formation. Comprehensive studies showed that the Suowa Formation carbonate source rocks have a favorable hydrocarbon-generating potential. The abundance of organic matter in the carbonate rocks is controlled mainly by sedimentary environment and inorganic compounds in the rocks, which is higher in the restricted platform facies than in the open platform facies. Organic carbon contents decrease with increasing CaO contents in the source rocks.  相似文献   

Water／Rock Interactions and Changes in Chemical Composition During Zeolite Mineralization   总被引：2，自引：0，他引：2  

张寿庭  赵鹏大等 《中国地球化学学报》2001,20(3):226-232

Systematic analysis and comparative study of the chemical compositons of rocks and ores from the main types of zeolite deposits in the surroundings of the Songliao Basic have shown that the process of formation of zeolite from volcanic and pyroclastic rocks is generally characterized by the relative purification of SiO2,i.e.,SiO2/Al2O3 ratios tend to increase,alkali eart elements (CaO MgO)and H2O are relatively enriched,and the alkali metals(K2O Na2O)are depleted in their total amount.The alkali metals K and Na follow different rules of migration and enrichment during the formation of mordenite and clinoptilolite.In the process of formation of mordenite more Na^ will be imported and K^ will be lost remarkably.On the contrary,in the process of formation clinoptilolite more K^ will be incorporated and Na^ will become obviously depleted.  相似文献   

冻融循环对钙剂改良土体分散性效果的影响     

苑晓青  吴泽炬  王清  陈慧娥  林森  牛岑岑  徐鑫 《吉林大学学报(地球科学版)》2023,(6):1812-1825

分散性土的水稳性极差,易形成管涌、洞穴、冲沟等破坏,季冻区土体在冻融循环过程所发生的冻胀融沉作用可能会增强土体的分散性。为了研究不同钙剂对土体分散性改良效果及冻融循环对改良效果的影响,先采用氧化钙和氯化钙两种钙离子剂对吉林西部地区分散性土体进行改良,确定最佳掺量后进行冻融循环试验;再分别通过分散性鉴定试验、无侧限抗压强度试验及微观结构试验探讨冻融循环对土体分散性改良效果的影响。试验结果表明,氯化钙对吉林西部土体分散性的改良效果优于氧化钙,氧化钙改良分散性土的最优掺量为1.6%,氯化钙改良分散性土的最优掺量为0.4%。冻融循环试验采用掺量为0.4%的氯化钙改良土。氯化钙改良土在经历不同次数的冻融循环后仍为非分散性土,其无侧限抗压强度在冻融循环次数0～5次有明显下降,但在冻融循环超过10次后下降趋势变缓且抗压强度基本保持在60 kPa;通过观察掺量为0.4%的氯化钙改良土在不同冻融循环次数的扫描电镜图像,推测冻融循环10次后其裂隙和孔隙的状态已趋于稳定。上述试验结果说明氯化钙可作为一种良好的改良剂对季冻区土体的分散性进行改良。  相似文献