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61.
Discussion of gas enrichment mechanism and natural gas origin in marine sedimentary basin,China 总被引:4,自引:0,他引:4
《科学通报(英文版)》2007,52(Z1)
There are abundant natural gas resources in Chinese marine sedimentary basin. The exploration hot shots of natural gas are the Palaeozoic marine strata here in recent years, and several large scale gas fields have been discovered. Chinese Palaeozoic high-post matured and coal measure hydrocarbon source rocks are mainly prone to gas generation in the present. This research considered that gas source rocks and TSR are the key cause of gas enrichment of marine strata. High-quality argillaceous and coal measure hydrocarbon rocks are distributed widely in the Palaeozoic marine strata, which have been in highly matured phase in the present. The argillaceous source rock generally contains various sulfates that could accelerate crude oil cracking to gas for TSR occurrence, and coal measure source rock mainly generates gas, so Chinese marine basin gives priority to accumulating gas. Marine strata have not founded oil reservoirs in the Sichuan Basin and Ordos Basin, and they consist mainly of dry gas. Marine natural gases are the mixed gases of oil cracking gas and coal-formed gas in a general way, oil cracking gases contain usually some H2S and CO2. Hydrocarbon carbon isotopes are very complicated, and methane and ethane isotopic values bear apparent reversal caused by thermal evolution and mixing among different genetic types of natural gas. Coal-formed gases are the main component of Chinese marine natural gas. The Upper Permian of the Sichuan Basin and the Carboniferous-Permian of the Ordos Basin coal measure hydrocarbon source rock present large hydrocarbon generation potential, which are the prospecting highlight of marine natural gas hereafter. Oil cracking gas exploration will be paid much attention to in the Tarim Basin because of the lack of coal measure hydrocarbon source rock. 相似文献
62.
《科学通报(英文版)》2007,52(Z1)
Generally, there are some anhydrites in carbonate reservoir, as H2S is also familiar in carbonate oil and gas reservoirs. Nowadays, natural gas with high H2S concentration is usually considered as TSR origin, so there is close relationship between H2S and anhydrite. On the contrary, some carbonate rocks with anhydrite do not contain H2S. Recently, researches show that H2S is only a necessary condition of H2S formation. The reservoir porosity, sulfate ion content within formation water, reservoir temperature, oil/gas and water interface, hydrocarbon and some elements of reservoir rock have great controlling effects on the TSR occurrence. TSR deoxidizes hydrocarbon into the acidic gas such as H2S and CO2, and the H2S formation is controlled by TSR occurrence, so the relationship among reaction room, the contact chance of sulfate ion and hydrocarbon, the reservoir temperature has great influence on the TSR reaction. H2S has relatively active chemical quality, so it is still controlled by the content of heavy metal ion. Good conditions of TSR reaction and H2S preservation are the prerequisite of H2S distribution prediction. This paper builds a predictive model based on the characteristic of natural gas reservoir with high H2S-bearing. In the porosity reservoir with anhydrite, the formation water is rich in sulfate and poor in heavy metal ion. Oil and gas fill and accumulate in the gas reservoir with good preservation conditions, and they suffered high temperature later, which indicates the profitable area of natural gas with high H2S-bearing. 相似文献
63.
生物可降解性聚碳酸亚丙酯/有机蒙脱土纳米复合材料的热氧老化 总被引:1,自引:0,他引:1
通过熔融插层法制备了聚碳酸亚丙酯(PPC)/有机蒙脱土(OMMT)纳米复合材料。研究了OMMT对PPC/OM-MT纳米复合材料热氧老化的影响。结果表明,老化以后复合材料的拉伸强度以及断裂伸长率的保留率均高于纯PPC。加入OMMT后,复合材料的热老化性能明显改善。 相似文献
64.
标准态下碳酸二甲酯合成体系热力学分析 总被引:1,自引:0,他引:1
用Benson基团贡献法计算了碳酸二甲酯(DMC)的热力学数据标准摩尔生成焓ΔfHmθ、标准摩尔生成吉布斯自由能ΔfHmθ和等压摩尔热容Cp,m;在标准态下,300~1 000 K温度范围内对比了甲醇或二甲醚(DME)氧化羰化合成DMC,甲醇或DME与CO2直接合成DMC,由合成气合成DMC,DME,甲醛或甲醇这些反应的焓变ΔfHmθ、吉布斯自由能变ΔfHmθ和平衡常数lnKθ.计算结果表明:在讨论的条件范围内,由DME氧化羰化合成DMC是热力学上可自发进行的反应,但DME和CO2反应合成DMC与甲醇和CO2反应合成DMC,均不能自发进行(需要通过耦合等方式来改变反应途径或重构反应体系,该反应才有可能进行).此计算将为合成DMC的反应路线设计以及新催化剂体系的探索提供热力学依据. 相似文献
65.
循环法制备高纯碳酸钙工艺研究 总被引:1,自引:0,他引:1
目的制备电子陶瓷工业用高纯碳酸钙。方法以工业碳酸钙为原料,采用改进的氢氧化物沉淀法,经过煅烧、浸出、沉淀、碳化等步骤制备高纯碳酸钙,并用原子吸收分光光度法和电位滴定法对杂质进行了分析,用粒度分析仪对产品粒度分布进行了测定。结果得到一条循环法生产高纯碳酸钙的优化工艺路线,该工艺过程如下:原料经煅烧后与氯化铵反应,加入沉淀剂过滤,除去杂质;将前工序煅烧时产生的CO2气体通入过滤后的滤液中,进行碳化反应;生成物经过滤干燥后即得到高纯碳酸钙;滤液循环使用。结论浸出温度,浸出时间,pH,pH调节试剂,碳化温度,洗涤水温等对产品均有影响。 相似文献
66.
贺干武 《邵阳学院学报(自然科学版)》2007,4(1):90-92
以碳酸铯作催化剂,碳酸钾作碱,以乙腈作溶剂,在回流的条件下酚与卤代烃反应高产率得到烷基芳醚. 相似文献
67.
基于化工生产中大量副产氯化钙,以氯化钙、氨水和二氧化碳为原料,在添加剂条件下对制备纳米碳酸钙进行了研究。实验研究了添加剂种类和用量、反应温度和二氧化碳流量等工艺条件对产物粒径的影响,采用XRD和TEM对产物进行了分析。实验结果表明:在添加剂条件下,以氯化钙、氨水和二氧化碳为原料可以制备纳米碳酸钙,反应条件温和能耗低;实验条件下制备的产物为方解石型近球状纳米碳酸钙。 相似文献
68.
Q.Xia Y.P.Wu 《复旦学报(自然科学版)》2007,46(5)
1 Results In order to overcome the inherent incompatibility of PC with graphite in the lithium ion battery system, improve their electrochemical performance at low temperature,phenyl tris-2-methoxydiethoxy silane (PTMS) has been studied as an additive to the PC-based electrolyte of lithium ion batteries with graphite anode. From the cyclic voltammogram for the graphite anode in the PC-based electrolyte,we find that in the case of the electrolyte without the additive,there is a large irreversible peak ne... 相似文献
69.
碳酸盐岩流体包裹体(NaCl-H2O)的合成及捕获机理分析 总被引:1,自引:0,他引:1
对碳酸盐岩原生、次生流体包裹体的形成机理进行了分析,并分别在压力为100MPa、温度为400—300℃和350℃条件下,利用高温高压釜合成了碳酸盐岩原生、次生流体包裹体(NaCl-H2O),模拟了包裹体的形成过程,并利用激光拉曼光谱及显微测温技术对合成包裹体的成分、均一温度、盐度等参数进行了定量分析。结果表明,合成的原生、次生包裹体气相与空气成分相符,其均一温度分别为372.8℃和321.02℃,盐度分别为23.22%和19.54%.与实验前设定的条件相符,从而验证了合成包裹体的准确性,并为进一步分析包裹体相态奠定了基础。 相似文献
70.
Summary Analog bile supersaturated with cholesterol was constituted, filtered and divided into equal portions containing no calcium or calcium, 2.5–15 mM. Aliquots were removed over the next 48 h and filtrates analyzed for cholesterol, bile acid and lecithin. Calcium accelerated cholesterol loss from solution in a dose-related fashion. 相似文献