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51.
基于石英包裹体成分测定、容矿断裂形成机制的理论分析、高温高压实验研究、动力学数学公式举例、含金流体瞬间就位过程及容矿断裂形成环境的探讨 ,提出了幔源含金流体主动就位机制。幔源流体萃取围岩金质并由导矿构造进入容矿断裂过程中 ,依自身扩张力或贯入力使岩石发生破裂 ,容矿断裂的产生和含矿流体沉淀近于同时形成。这为金矿脉与基性 -超基性脉岩的关系、金矿脉在空间呈有规律性分布和建立模式的研究增加了新的内容。  相似文献   
52.
本文论述了中国东南大陆中、新生代岩浆作用的多旋回性和迁移性,构造演化与岩石系列和岩石组合的关系。前寒武纪岩石圈制约本区中、新生代岩浆作用和成矿作用,并在三种岩石围岩石学一地球物理综合模型中反映。总结了四个主要构造期岩浆作用源区特征和构造背景,并根据不同大地构造单元在碰撞造山后近南北向刊近北东向伸展裂解,从造山带挤压碰撞向伸展裂解机制转换过程探讨了中、新生代岩浆作用和壳幔演化动力学。  相似文献   
53.
滇西地区基性 超基性岩、碱性岩中的长石、石榴子石、橄榄石等单矿物及羊拉铜矿区二叠世海相玄武岩的铅同位素组成可以代表原始地幔的铅同位素组成 ,由此确定的该区上地幔铅同位素组成变化范围为 2 0 6Pb/2 0 4Pb =1 7.877~1 8.5 0 6,平均 1 8.1 0 8,2 0 7Pb/2 0 4Pb=1 5 .470~1 5 .5 87,平均 1 5 .479,2 0 8Pb/2 0 4Pb=3 7.797~ 3 8.5 67,平均 3 8.1 77。研究发现 ,由于受地壳物质的混染和成岩后U、Th衰变产生的放射成因铅的影响 ,这些幔源岩石全岩铅同位素组成已不能代表原始上地幔的铅同位素组成 ;金顶铅锌矿床的铅并非上地幔来源 ,而是相当于下地壳来源的铅与兰坪盆地沉积岩铅二者的混合铅。  相似文献   
54.
A new biotechnological synthetic approach to 4-hydroxybenzoic acid is reported. Thauera aromatica cells produce the phenylphosphate carboxylase enzyme that selectively carboxylates phenylphosphate in the para position, without any formation of the ortho isomer. Here we show that the enzyme also works in supercritical carbon dioxide, opening a new technological solution to the recovery of the products that is a key problem when aqueous media are used. The enzyme shows an activity comparable with that shown under CO2 pressure in aqueous media and does not require the presence of NaHCO3.  相似文献   
55.
地幔流体基本特征及成因   总被引:5,自引:0,他引:5  
与构造环境密切相关的氧逸度是控制地幔流体成分的最根本因素CO2和H2O为大多数地幔流体的主要成分。俯冲板块的脱水脱气作用、地幔原始残留挥发份及地幔部分熔融作用是地幔流体的主要来源。  相似文献   
56.
Two marine bacterial isolates from drill mud cuttings obtained from Agbara oilfield,Staphylococcus sp. andBacillus sp., were cultured aerobically in the presence of varying concentrations (0, 25, 50, and 75 μg/ml) of drilling fluids to determine the effects of concentration of toxicants on their growth. With the exception of Clairsol, Enviromul, and Baroid mineral oil, which had little or no effect, the exponential growth ofBacillus sp. was depressed by all other test chemicals. Additionally, all test chemicals except Clairsol had no effect on lag phase of growth ofBacillus sp. WithStaphylococcus sp. the depressive effect on the exponential phase of growth was shown by almost all test chemicals. There was enhancement of both growth rate and generation times ofStaphylococcus sp. and decrease of those ofBacillus sp. with increasing concentrations of drilling fluids. These results show that while some drilling fluids may be stimulatory or depressive to bacterial growth, others may be without effect.  相似文献   
57.
Changes in Tilapia guineensis gonads exposed for 12 weeks to XP-07 at a concentration of 2.5, 1.25, 0.63, or 0.32% were investigated using a static renewal method. The histological changes noted in the gonads of the exposed fish were inhibition of maturation in oocytes or spermatogenesis. In contrast, the four stages of sperm or ova development were present in the control fish and spawning occurred. The increasing degeneration (artesia) of maturing egg resulted in complete absence of matured eggs in the female gonads of fish exposed to highest concentration (2.5%) of drilling fluid. The gonadal somatic index (GSI) values were recorded in a decreasing order towards the higher tested concentrations. The GSI values ranged from 3.11 to 1.47% in females and from 0.42 to 0.16% in males, whereas in control, it was 3.18% for females and 0.52% for males. Data showed that XP-07 exerted adverse effects on reproductive processes, which led to impairment in the reproductive success of T. guineensis.  相似文献   
58.
Significant amount of work is reported on development of vegetable oil based metalworking fluids (MWFs). Many also report on development and performance evaluation of vegetable based oils. For many of these water-based MWFs with vegetable oils, much effort is focused on stable emulsification of vegetable oil in water using a variety of surfactants. It has been found that surfactant-free stable emulsification of oil in water is possible through ultrasonic vibration. However, emulsification through ultrasonic atomization has not yet been considered, and the feasibility of emulsified metalworking fluids through ultrasonic atomization has not been investigated. In this paper, stable emulsification of vegetable oil in water has been achieved through ultrasonic atomization without using any surfactant. The emulsified vegetable oil in water is directly used to investigate its effectiveness as MWF in milling operations. Lower cutting forces, chip thickness, and burr amount are observed with vegetable oil-in-water emulsion compared to conventional MWF. The experimental results show strong potential for vegetable oil-in-water emulsion obtained through ultrasonic atomization as an effective MWF.  相似文献   
59.
近年来,随着对环保的重视,钻井过程中产生的废弃钻井液的处理也越来越受到钻井人的关注.文章针对国内废弃钻井液处理方法的发展现状,从中国海上和陆地废弃钻井液着手,分别论述了海上和陆地废弃钻井液处理中,水基和油基废弃钻井液的处理方法,以及现场应用情况.并对海上以及陆地废弃钻井液的处理进行对比分析,可以更直观的选出适合某地区的废弃钻井液处理方法,对现场工作有一定的帮助.  相似文献   
60.
为了明确压裂返排液中影响回用的突出污染物,从而针对性地研究现场处理技术,采用水质矩阵法对苏里格气田常用的两种体系压裂返排液的水质特性进行评价。结果表明:影响胍胶压裂返排液回用的污染物重要程度排序为钙镁离子、铁离子、悬浮物和pH值;影响可回收体系压裂返排液回用的污染物重要程度排序为悬浮物、pH值、钙镁离子和铁离子,两者差异明显。以此为基础,针对胍胶压裂返排液,提出“化学絮凝、离子控制、金属网过滤”的现场处理工艺,钙镁离子降低了83.7%,铁离子降低了79.6%,悬浮物降低了85.0%;针对可回收体系压裂返排液,提出“重力沉降、金属网过滤”的现场处理工艺,悬浮物降低了81.0%,处理后水质达到重复配液要求。  相似文献   
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