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91.
在油井开采原油时,会产生伴生气,而在高压和低温环境中会生成天然气水合物,进而堵塞运输管道,因此研究油砂体系(含原油的体系)和纯石英砂体系(不含原油的体系)中水合物生成情况具有重要意义。在初始压力为4.00、6.00、8.00 MPa,石英砂粒径为20、30、60、80目,温度恒定的条件下,研究了油砂体系和纯石英砂体系中甲烷水合物的生成情况以及最终耗气量。结果表明,在初始压力相同的油砂体系中,石英砂粒径越小,水合物生成诱导期越短,水合物生成速率越大。研究石英砂粒径对水合物生成最终耗气量的影响发现,随着石英砂粒径的减小,耗气量先增加后减少,当石英砂粒径为60目时,耗气量达到最大,其值为0.19 mol。同时,对油砂体系和纯石英砂体系中水合物生成情况进行了对比。结果表明,由于两种体系中都存在SDS(十二烷基硫酸钠)溶液,因此水合物生成速率相差不大;在石英砂粒径相同的条件下,油砂体系中最终耗气量小于纯石英砂体系中的最终耗气量,这说明原油对水合物生成具有抑制作用。在油砂体系中,压力越大,越有利于水合物的生成。 相似文献
92.
In the chemical looping with oxygen uncoupling (CLOU) process,CuO is a promising material due to the high oxygen carrier capacity and exothermic reaction in fuel reactor but limited by the low melting point.The combustion rate of carbon is faster than the decoupling rate of oxygen carrier (OC).Hence,high tem-perature tolerance and rapid oxygen release rate of CuO modified by three different ores were investi-gated in this study.The kinetics analysis of oxygen decoupling with Cu-based oxygen carriers was also evaluated.Results showed that CuO modified by chrysolite had faster oxygen release rate than that of CuO.Limestone showed obvious positive effect on the oxidization process.The selected OCs could keep stable in at least 20 cycles,for about 1200 min.Shrinking core model (SCM) fitted well for the decoupling process in the temperature range of 1123-1223 K.Reduction rate kinetic information may aid in the development of chemical looping with oxygen uncoupling (CLOU) technologies during reactor design and process modeling.Ternary doped copper oxide with chrysolite and limestone could improve the reactivity of CuO in decoupling and coupling process and also improve the high temperature tolerance. 相似文献
93.
通过熔融共混方法制备导电高分子复合材料丙烯腈-苯乙烯-丙烯酸酯共聚物(ASA)/天然石墨(NGR)/炭黑(CB),采用电磁屏蔽测量仪、四探针电阻率测量仪和动态热机械分析仪对复合材料的电性能和力学性能进行详细研究。结果表明,ASA/NGR复合材料的体积电阻率随着炭黑含量增加而增加;同时在30 MHz~1500 MHz范围内,复合材料的电磁屏蔽性能从28 dB提高到38 dB,符合商业要求。炭黑的加入大大改善了材料力学性能,弯曲强度从31 MPa增加到41 MPa;动态储能模量从4.6 GPa增加到14.5 GPa。 相似文献
94.
Rizwana Begum Syed Nabi Rupesh Tayade Adil Hussain Arjun Adhikari In-Jung Lee Gary J. Loake Byung-Wook Yun 《International journal of molecular sciences》2021,22(10)
In the last two decades, global environmental change has increased abiotic stress on plants and severely affected crops. For example, drought stress is a serious abiotic stress that rapidly and substantially alters the morphological, physiological, and molecular responses of plants. In Arabidopsis, several drought-responsive genes have been identified; however, the underlying molecular mechanism of drought tolerance in plants remains largely unclear. Here, we report that the “domain of unknown function” novel gene DUF569 (AT1G69890) positively regulates drought stress in Arabidopsis. The Arabidopsis loss-of-function mutant atduf569 showed significant sensitivity to drought stress, i.e., severe wilting at the rosette-leaf stage after water was withheld for 3 days. Importantly, the mutant plant did not recover after rewatering, unlike wild-type (WT) plants. In addition, atduf569 plants showed significantly lower abscisic acid accumulation under optimal and drought-stress conditions, as well as significantly higher electrolyte leakage when compared with WT Col-0 plants. Spectrophotometric analyses also indicated a significantly lower accumulation of polyphenols, flavonoids, carotenoids, and chlorophylls in atduf569 mutant plants. Overall, our results suggest that novel DUF569 is a positive regulator of the response to drought in Arabidopsis. 相似文献
95.
国家自然科学基金对学科发展具有扶持、引导作用, 其资助情况能反映出学科发展态势、研究前沿和热点。以2010—2019年国家自然科学基金对盐湖研究的资助项目数据为分析对象, 利用EXCEL、R Studio、VOSviewer等软件对资助年度、资助金额、依托单位、资助类别、项目名称、关键词等内容进行统计分析, 揭示了国家自然科学基金对盐湖基础研究的资助力度、趋势、研究团队分布, 发现当前盐湖热点研究方向包括盐湖相化学与溶液化学、盐湖资源分离与利用技术、盐湖资源综合利用技术、盐湖成盐规律与机制、盐湖锂资源利用技术、盐湖化学性质研究。 相似文献
96.
详细介绍了2000m^3高压天然气球罐工程的制造、安装过程,并指出每个环节的控制要点。球罐投入运行后,工作状况良好。 相似文献
97.
98.
Conversion of natural gas to liquid fuels is a challenging issue. In SMDS process natural gas is first partially oxidized with pure oxygen to synthesis gas (a mixture of H2 and CO) which is then converted to high quality liquid transportation fuels by utilizing a modernized version of the Fischer-Tropsch reaction. This paper presents a computer simulation of the first stage of the process, i.e. the synthesis gas production from natural gas. ASPEN PLUS equipped with a combustion databank was used for calculations. Concentrations of over 30 combustion species and radicals expected in the synthesis gas have been calculated at equilibrium and several non-equilibrium conditions. Using a sensitivity analysis tool, the relative feed flow rates and reactor parameters have been varied searching to maximize the CO/O2 yield as well as to minimize the undesired nitrogen compounds in the product stream. The optimum reactor temperature for maximizing the CO mole fraction in the synthesis gas was also calculated. 相似文献
99.
聚合物防老化稳定剂的协同作用机理 总被引:18,自引:0,他引:18
从聚合物热氧老化和光氧老化机理出发,介绍了不同稳定剂间的相互作用,可能产生的协同及反协同作用机理以及一些实用实例。 相似文献
100.
Effect of additives on formation of natural gas hydrate 总被引:1,自引:0,他引:1
The formation of natural gas hydrate (NGH) is studied in this work. Kinetics data of hydrate formation with no agitation were collected at various concentrations of the aqueous solutions with different additives such as alkylpolyglucside, sodium dodecyl benzene sulfonate and potassium oxalate monohydrate. Various kinds of additive increased the formation rates of NGH and its storage capacity and reduced the induction time of NGH formation. Moreover, the storage capacity, the induction time and the hydrate formation rate were influenced by the concentration of the aqueous solution. 相似文献