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41.
熔融碳酸盐燃料电池(MCFC)电堆的电气与温度特性决定其性能和可靠性,立足于控制MCFC电堆的输出电压,从单体电池推及电堆,比较全面地对MCFC电堆输出电压以及与之相关的电流密度,燃料气体利用率等特性加以分析,在系统级上建立了由一组变系数偏微分方程和积分方程描述的动态模型,并以外部负载扰动为例讨论了各状态量之间的相互关系,分析和建模的正确性为仿真结果所证实,所得结论有助于控制方案和流场的设计,以及电池材料的选择。  相似文献   
42.
Based on detailed studies, this paper proposesthat in the Tarim Basin, hydrocarbon reservoirs widespreadeither in vertical sequences or in plane and high-porosity andhigh-permeability reservoirs are developed all over the basin.However, obvious difference and heterogeneity exist amongdifferent kinds of reservoirs. The lithologic characteristics,reservoir space types and reservoir properties in variousstrata have been probed. The result indicates that althoughthe Paleozoic carbonates have been deeply buried for a longperiod, high-quality reservoirs with the porosity of up to 5%—8% (12% as the maximum) and the permeability of10×10-3—100×10-3 μm2 (1000×10-3 μm2 as the maximum)can be found in certain areas. These include the area withthe development of reefs and carbonate beaches, the weath-ered-crust buried-hill belts that have undergone thelong-term exposure, weathering and leaching, the area withthe development of dolomitization, and those areas that haveexperienced the resolution of carbonic acid and organic acidgenerated by the maturity of the organic matter. Finally, thegenesis of the high-porosity and high-permeability reservoirsin deep-buried conditions (with the depth more than 3500 m)have been investigated thoroughly.  相似文献   
43.
本实验,首先根据铈易被氧化成四价铈的性质,使Ce(OH)3lfnywx o C(OH)4.须稀酸(PH≈2.5)中,Ce(OH)4不溶解,而E(OH)3能溶解,使铈与其他轻稀土元素得到初级分离,再根据四价铈容易被磷酸三丁酯(TBP)萃取的性质,使铈得到进一步纯化,后经草酸沉淀、过滤、灼烧得到纯的二氧化铈。  相似文献   
44.
鄂尔多斯盆地的早奥陶世沉积可划分为西缘末端变陡的碳酸盐岩缓坡、东缘蒸发-局限台地和南缘镶边碳酸盐岩台地3个沉积区。岩相古地理的发展可划分为3个阶段,即冶理—亮甲山期为稳定的发展阶段,早、晚马家沟期为岩相分异阶段,峰峰期为中奥陶世陆源浊积盆地这一新的发展阶段的前奏。其演化具有东升西降的特点,东部沉积区的沉积相演化为一个向上变浅的沉积序列,而西部为一个向上变深的沉积序列。  相似文献   
45.
<正> Hetianhe is a big carbonate gas field which isfound and demonstrated in the period of "Chinese NationalNinth 5-Year Plan". The proved reserve of Hetianhe gas fieldis over 600 ×108 m3. Its main producing layers are Carbon-iferous bioclastic limestone and Ordovician carbonate com-posed of buried hill. The former is stratified gas pool withwater around its side, and the latter is massive gas pool withwater in its bottom. The gases in the gas pools belong to drygases with normal temperature and pressure systems. Basedon the correlation of gas and source rock, the gases aremainly generated from Cambrian source rocks. According tothe researches on source rock and structure evolution, andthe observations on the thin section to reservoir bitumen andthe studies on homogenization temperature of fluid inclu-sions, the gas pool has been identified and divided into threeformation periods. The first is Late Caledonian when the oilgenerated from the Cambrian source rocks and migratedalong faults, as a form of liquid facies into Ordovician carbonate res-ervoir and accumulated there. After that, the crustuplifted, the oil reservoir had been destroyed. The second isLate Hercynian when condensate gases generated from theCambrian source rocks and migrated into Ordovician res-ervoir, as a form of liquid facies. Since the fractures hadreached P strata, so the trap might have a real poor preser-vation condition, and the large-scale gas pool formation hadnot happened. The third gas reservoir formation period oc-curred in Himalaya. The fractures on both sides of Hetianhegas field developed violently under the forces of compression,and thus the present fault horst formed. The dry gases gen-erated from Cambrian source rocks and migrated upwardsas the form of gas facies into Ordovician and Carboniferousreservoirs, and the large gas pool as discovered at presentwas formed finally.  相似文献   
46.
TCE的物理化学特性及其生物降解作用   总被引:3,自引:2,他引:1  
以加拿大一厂址区碳酸盐岩水是中地下受到三氯惭烯(TCE)化合物的污染作为实例,对TCE的物理化学特性及其降解作用进行论述,指出TCE污染物的生物降解作用的存在的,但是不完全,因此,当TCE污染物深度明显超标时,仍应考虑采取去除污染措施。  相似文献   
47.
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   
48.
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   
49.
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   
50.
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   
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