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Multi-shelled cuO microboxes for carbon dioxide reduction to ethylene

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Nano Research 2020年第3期13卷 768-774页

作者： Dongxing Tan Jianling Zhang Lei Yao Xiuniang Tan Xiuyan cheng Qiang Wan Buxing han Lirong Zheng Jing Zhang Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of ColloidInterface and Chemical ThermodynamicsCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing100190China School of chemical Sciences University of Chinese Academy of SciencesBeijing100049China Physical Science Laboratory Huairou National Comprehensive Science CenterBeijing101400China Beijng Synchrotron Radiation Facility(BSRF) Institute of High Energy PhysicsChinese Academy of SciencesBeijing100049China

The electroreduction of cO2 to valuable chemicals and fuels offers an effective mean for energy storage.Although cO2 has been efficiently converted into c1 products(e.g.,carbon monoxide,formic acid,methane and methanol),its convention into high value-added multicarbon hydrocarbons with high selectivity and activity still remains challenging.here we demonstrate the formation of multi-shelled cuO microboxes for the efficient and selective electrocatalytic cO2 reduction to c2h4.Such a structure favors the accessibility of catalytically active sites,improves adsorption of reaction intermediate(cO),inhibits the diffusion of produced Oh−and promotes c-c coupling reaction.Owing to these unique advantages,the multi-shelled cuO microboxes can effectively convert cO2 into c2h4 with a maximum faradaic efficiency of 51.3%in 0.1 M K2SO4.This work provides an effective way to improve cO2 reduction efficiency via constructing micro-and nanostructures of electrocatalysts.

关键词： multi-shelled cuO microboxes nanocrystals cO2 reduction c2h4

h2 production by ethanol decomposition with a gliding arc discharge plasma reactor

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Frontiers of chemical Science and Engineering 2013年第2期7卷 145-153页

作者： Baowei WANG Wenjie GE Yijun LV Wenjuan YAN Key Laboratory for Green chemical Technology of the Ministry of Education School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China

一个滑行的弧分泌物(GRD ) 反应堆被用来把乙醇分解成首先有 ch4， c2h2， c2h4，和 c2h6 的小数量的 h2 和公司。乙醇集中，电极差距，输入电压和 Ar 流动率都影响了乙醇的变换，结果从 40.7% ～ 58.0%。有趣地，为所有试验性的条件， ... 详细信息

一个滑行的弧分泌物(GRD ) 反应堆被用来把乙醇分解成首先有 ch4， c2h2， c2h4，和 c2h6 的小数量的 h2 和公司。乙醇集中，电极差距，输入电压和 Ar 流动率都影响了乙醇的变换，结果从 40.7% ～ 58.0%。有趣地，为所有试验性的条件， Sh2/ScO 选择比率在约 1.03 点是相当稳定的。为乙醇的分解的机制也被描述。

关键词：等离子体反应器乙醇浓度滑动弧放电 c2h2 分解生产 c2h4 电极间隙

Effect of cO_2 on the structural variation of Na_2WO_4/Mn/SiO_2 catalyst for oxidative coupling of methane to ethylene

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Journal of Energy chemistry 2015年第4期24卷 394-400页

作者： Jia Shi Lu Yao changwei hu Key Laboratory of Green chemistry and Technology Ministry of EducationCollege of ChemistrySichuan University

In this work,the influence of cO2 on the structural variation and catalytic performance of Na2WO4/Mn/Si O2 for oxidative coupling of methane to ethylene was investigated. The catalyst was prepared by impregnation method and characterized by XRD,Raman and XPS techniques. Appropriate amount of cO2 in the reactant gases enhanced the formation of surface tetrahedral Na2WO4 species and promoted the migration of O in MOx,Na,W from the catalyst bulk to surface,which were favorable for oxidative coupling of methane. When the molar ratio of ch4/O2/cO2 was 3/1/2,enriched surface tetrahedral Na2WO4 species and high surface concentration of O in MOx,Na,W were detected,and then high ch4 conversion of 33.1% and high c2h4 selectivity of 56.2% were obtained. With further increase of cO2 in the reagent gases,the content of active surface tetrahedral Na2WO4 species and surface concentration of O in MOx,Na,W decreased,while that of inactive species（Mn WO4 and Mn2O3） increased dramatically,leading to low ch4 conversion and low c2h4 selectivity. It could be speculated that Na2WO4 crystal was transformed into Mn WO4 crystal with excessive cO2 added under the reaction conditions. Pretreatment of Na2WO4/Mn/Si O2 catalyst by moderate amount of cO2 before OcM also promoted the formation of Na2WO4 species.

关键词： Oxidative coupling of methane cO2 c2h4 Na2WO4/Mn/SiO2catalyst Structural variation

Theoretical study of the mechanism for c-h bond activation in spin-forbidden reaction between Ti^+ and c_2h_4

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Science china chemistry 2009年第3期52卷 295-303页

作者： LV LingLing1, LIU XinWen1, YUAN Kun1, WANG XiaoFang1 & WANG Yongcheng2 1 college of Life Science and chemistry, Tianshui Normal University, Tianshui 741001, china 2 college of chemistry and chemical Engineering, Northwest Normal University, Lanzhou 730070, china college of Life Science and chemistry Tianshui Normal University Tianshui China college of chemistry and chemical Engineering Northwest Normal University Lanzhou China

The mechanism of the spin-forbidden reaction Ti+(4F, 3d24s1) + c2h4 → Tic2h2+ (2A2) + h2 on both doublet and quartet potential energy surfaces has been investigated at the B3LYP level of theory. crossing points between the potential energy surfaces and the possible spin inversion process are discussed by means of spin-orbit coupling (SOc) calculations. The strength of the SOc between the low-lying quartet state and the doublet state is 59.3 cm-1 in the intermediate complex IM1-4B2. Thus, the changes of its spin multiplicity may occur from the quartet to the doublet surface to form IM1- 2A1, leading to a sig-nificant decrease in the barrier height on the quartet PES. After the insertion intermediate IM2, two dis-tinct reaction paths on the doublet PES have been found, i.e., a stepwise path and a concerted path. The latter is found to be the lowest energy path on the doublet PES to exothermic Tic2h2+ (2A2) + h2 products, with the active barrier of 4.52 kcal/mol. In other words, this reaction proceeds in the following way: Ti++c2h4 →4Ic→IM1-4B2→4,2ISc→IM1- 2A1→[2TSins]→IM2→[2TSMcTS]→IM5→Tic2h2+(2A2)+h2.

关键词： Ti+(4F) and c2h4 spin-forbidden reaction mechanism spin-orbit coupling (SOc) concerted path

Molecular Simulations of Fcc Dry Gas components Adsorption in Zeolite Y

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china Petroleum Processing & Petrochemical Technology 2016年第1期18卷 100-107页

作者： Ding Xue Liu Yibin Yang chaohe Shan honghong chen Fangwen State Key Laboratory of heavy Oil Processing China University of Petroleum Institute of Unconventional hydrocarbon and New Energy Sources China University of Petroleum

Adsorption of Fcc dry gas components, hydrogen(h_2), nitrogen(N_2), methane(ch_4), ethane(c_2h_6) and ethylene(c_2h_4) in zeolite Y was studied by performing the Grant canonical Monte carlo(GcMc) simulations at 298K and 823K and under a pressure range up to 10 MPa. Simulation results were analyzed using the Langmuir model, which presented fitting of dry gas components adsorption to be suggested as the monolayer adsorption. c_2h_4 presented most single adsorption amount, which reached 7.63 mol/kg at 298K under a pressure of 200kPa. Thermodynamic parameters of the Gibbs free energy change, enthalpy change and entropy change were analyzed based on adsorption equilibrium constant obtained from the GcMc simulations. The results suggested that it was more favorable for c_2h_4 to be adsorbed in zeolite Y. Adsorption molecules were in ordered arrangement in the zeolite, and c_2h_4 exhibited a more orderly arrangement than other components. Additionally, a competition in the adsorption of a mixture of dry gas components was found, and supercages were the priority adsorption space. The competition was favorable to ch_4 and c_2h_6, and the competitive power was affected by temperature.

关键词：催化裂化干气分子模拟 Y型沸石吸附量组分吸附平衡常数 GcMc c2h4

chemical Dynamics Simulations of the hydroxyl Radical Reaction with Ethene

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chinese Journal of chemical Physics 2013年第6期26卷 765-773,I0005页

作者： Jiaxu Zhang Li Yang Diego Troya Beijing National Laboratory for Molecular Sciences Institute of Chemistry Chinese Academy ofSciences Beifing 100190 China Technical Institute of Physics and chemistry Chinese Academy of Sciences Beijing 100190 China Department of chemistry Virginia Tech Blacksburg VA 24051 USA

我们在场有用电子结构计算和 directdynamics 模拟的 ethene 的氢氧根激进分子的反应的理论研究。在 ccSD (T)/augccpVTZ//MP2/augccpVDZ 水平的 highaccuracy 电子结构计算被执行了描绘各种各样的反应小径的势能表面的代表性的区域，包... 详细信息

我们在场有用电子结构计算和 directdynamics 模拟的 ethene 的氢氧根激进分子的反应的理论研究。在 ccSD (T)/augccpVTZ//MP2/augccpVDZ 水平的 highaccuracy 电子结构计算被执行了描绘各种各样的反应小径的势能表面的代表性的区域，包括 Ohaddition 和 habstraction。这些 ab initio 计算被采用了为对 Oh+c2h4 反应特定的 MSINDO semiempirical hamiltonian 导出参数的一个改进集合。specificreactionparameter hamiltonian 精确地捕获 ab initio 数据，并且被用来在 210 kcal/mol 的范围在碰撞精力执行 Oh+c2h4 反应的直接 quasiclassical 轨道模拟。计算的生气的节表明 Ohaddition 反应根本在 habstraction 上统治精力。另外，当那为抽象对应于激活的，和这些趋势时，增加的刺激功能使人想起一个无障碍的俘获过程能被连接到两反应的 transitionstate 精力。我们注意为在这个工作的 Oh+c2h4 反应的精确 semiempirical hamiltonian 的开发要求了实验分散修正的包括，它将在为 longrange，分子间的吸引力变得重要的未来应用程序是重要的。

关键词：化学动力学模拟自由基反应羟基自由基乙烯反应 ccSD(T) 结构计算 c2h4 碰撞能量

Thermodynamic Analysis of Formation of Low-carbon Olefins via coal Gasification coupling c_1 Reaction

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china Petroleum Processing & Petrochemical Technology 2018年第3期20卷 24-31页

作者： Xu Jing Tu Nan Liu Tong college of Mechanical and Electrical Engineering Xi'an Polytechnic University

The complex reaction system of the coal gasification coupling c1 reaction was analyzed based on the principles of thermodynamics. The results show that an increase in the temperature is beneficial to the generation of hydrocarbons with high carbon-atom contents, in which the alkane yield is higher than the alkene yield. The complex reaction system consisting of c, h_2O, cO, cO2, h_2, c_2h_4, c_3h_6 and c_4h_8 was studied, and the obtained results indicated that when the maximum mole fraction content of c_2―c4 olefins was regarded as the optimized objective function, the optimum temperature was approximately 648 K, the pressure was 0.1 MPa, the feed ratio was approximately 0.6, and the maximum mole fraction content of c_2―c_4 olefins was approximately 28.24%. The thermodynamic simulation and calculation of the complex reaction system can provide a basis for the determination and optimization of actual process conditions and are therefore of great theoretical and practical significance.

关键词：复杂反应系统热力学煤气化石蜡低碳最佳温度 c2h4 c3h6

O3和c2h4在介质阻挡放电转化NO中的作用

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高电压技术 2008年第1期34卷 103-106页

作者：钟侃聂勇汪晶毅王黎明关志成贾志东清华大学深圳研究生院

放电等离子体结合选择催化还原脱除NOx是一项很有前景的贫燃尾气治理技术,其预处理过程中,尾气中NO会向NO2转化。为了解重要的活性中间产物O3的作用和生成特性以及常见的烃类添加剂c2h4的作用,在介质阻挡放电等离子体反应器内进行了相... 详细信息

放电等离子体结合选择催化还原脱除NOx是一项很有前景的贫燃尾气治理技术,其预处理过程中,尾气中NO会向NO2转化。为了解重要的活性中间产物O3的作用和生成特性以及常见的烃类添加剂c2h4的作用,在介质阻挡放电等离子体反应器内进行了相关实验研究。监测N2/O2,N2/O2/NO,N2/O2/c2h4,N2/O2/NO/c2h4共4个体系下的O3产生特性,并通过N2/O2/NO和N2/O2/NO/c2h4体系的比较考察c2h4对NO转化影响的结果表明:除N2/O2体系外,其它体系中都不会产生大量的O3;c2h4不但提高了NO的转化率,还明显地抑制放电过程NO的生成。可以推断,O3作为氧化剂能促进NO向NO2的转化,c2h4添加剂可以提高NO的转化率。

关键词： O3 c2h4 贫燃发动机尾气氮氧化物介质阻挡放电等离子体

ceO_2对cucl/活性炭吸附剂c_2h_4/c_2h_6吸附分离性能促进作用（英文）

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物理化学学报 2015年第11期31卷 2158-2164页

作者：邢建东敬方梨储伟孙红丽喻磊张欢罗仕忠四川大学化学工程学院成都610065 四川大学新能源与低碳技术研究院成都610207

通过等体积浸渍方法制备了添加ceO2助剂的用于c2h4/c2h6吸附分离的cucl/活性炭(Ac)吸附剂,使用氮气吸附-脱附曲线、X射线衍射(XRD)、X射线光电子能谱(XPS)、扫描电子显微镜(SEM)、能量分散X射线光谱(EDX)等分析方法对吸附剂进行了表征.... 详细信息

通过等体积浸渍方法制备了添加ceO2助剂的用于c2h4/c2h6吸附分离的cucl/活性炭(Ac)吸附剂,使用氮气吸附-脱附曲线、X射线衍射(XRD)、X射线光电子能谱(XPS)、扫描电子显微镜(SEM)、能量分散X射线光谱(EDX)等分析方法对吸附剂进行了表征.结果表明,吸附剂表面cu(II)在氮气气氛焙烧过程中被部分还原成cu(I).重点研究了ce元素的添加对于吸附剂的c2h4/c2h6吸附分离性能的影响,等温吸附曲线结果表明添加了ceO2的吸附剂通过降低乙烷的吸附容量从而显著提高了吸附分离性能.XRD及XPS结果表明,和未添加助剂样品相比,其表面晶体团簇较小,分散性更好,cu(II)还原程度更高.添加ceO2的吸附剂样品5ce50cu(ceO2和cucl2的质量分数(w)分别为5%和50%)获得了最好的吸附分离效果,相对于未添加ceO2的样品50cu,其在660 kPa下的吸附选择性由4.2提升到8.7.

关键词： c2h4 变压吸附吸附选择性 ceO2助剂 cu(I)活性位表面表征