稀土金属助催的甲醇水蒸汽重整制氢催化剂的研究

制备稀土金属离子助催的铜锌基醇水蒸汽重整催化剂并分别比较了铜锌和两种以稀土Ce^3 ,Zr^4 为助催剂的铜锌催化剂上甲醇水蒸汽重整制氢的催化性能：在220℃反应条件下，Cu-ZnO,Cu-ZnO-Ce2O3和Cu-ZnO-ZrO2的甲醇转化率分别为28.1%、37.3%和51.6%，后两个催化剂的氢选择性高达100％，CO的选择性为0。Cu-ZnO-ZrO2催化剂经60h的运转后，催化剂的性能不变，触氧实验表明该催化剂能满足甲醇燃料电池电动车启动温度低、CO2选择性高的要求。     

CuMn2O4/HZSM-5催化二甲醚水蒸气重整制氢的试验研究

摘要： 搭建了二甲醚水蒸气重整制氢的小样模拟台架,并制备了二甲醚重整制氢催化剂.研究了不同水解活性组分、甲醇重整活性组分和煅烧温度下的尖晶石复合催化剂对二甲醚水蒸气催化重整制氢性能的影响.结果发现：不同水解活性组分中,HZSM 5（硅铝摩尔比r=n(SiO2)/n(Al2O3)=38）的双功能催化剂的H2产率最高;甲醇重整活性组分中,铜锰尖晶石结构催化组分（CuMn2O4）的双功能催化剂的H2产率最高;煅烧温度对CuMn2O4双功能催化剂的催化效果有明显影响,其中煅烧温度为700 °C时H2产率最高.     

醇盐法制备Cu—ZnO／SiO2催化剂及其活性

用醇盐法制备Cu-ZnO/SiO2催化剂，该催化剂在甲醇脱氢合成甲酸甲酯反应中的活性和稳定性均优于浸渍法和离子交换法制备的Cu-ZnO/SiO2催化剂，根据差示扫描量热图谱和程序升温还原图图的测定，研究了焙烧温度及还原温度对催化活性的影响，并对ZnO的助催化性能进行了研究。     

CeO2对甲醇水蒸汽重整反应催化剂的影响

研究了Cu/Zn/Ce/Al催化剂上甲醇水蒸汽重整反应，采用X射线衍射分析和程序升温 试验等技术对催化剂的物相结构和还原特性进行了探讨。结果表明：添加CeO2增加CuO的分散性，提高催化剂的稳定性。     

黄铜矿制备铜基催化剂催化甲醇水蒸气重整制氢的研究

以黄铜矿为原料,采用高温焙烧处理制备铜基催化剂用于催化甲醇水蒸气重整制氢反应,借助X射线粉末衍射仪、场发射扫描电子显微镜、H₂程序升温还原、甲醇水蒸气重整制氢试验以及原位漫反射傅里叶变换红外光谱仪等对所制催化剂进行表征。结果表明,改变焙烧温度可调节铜基催化剂中铜位点的配位结构,黄铜矿在800℃下焙烧所得催化剂的催化性能最佳。     

甲醇裂解的创新实验

为了全面掌握流动法—甲醇裂解实验中催化剂的活性,采用浸渍法制备了Pd/CeO2-ZrO2(Pd/CZ)和Pd-Co/CeO2-ZrO2(Pd-Co/CZ)催化剂。运用X射线衍射、N2吸附-脱附、储氧量测定、CO化学吸附、H2程序升温还原(H2-TPR)和X射线光电子能谱对催化剂进行了表征,考察了其催化甲醇裂解反应活性。结果表明,Co的添加不仅提高了催化剂的储氧性能,而且大大提高了催化剂活性组分的分散程度,同时,使得金属和载体间相互作用增强,增加了Pd周围的电子密度,使Pd保持在部分氧化状态Pdδ+(0δ2),进而提高了甲醇催化裂解反应的活性,280℃时甲醇能达到完全裂解,实验效果得到明显改善。     

Co-Mo_2C/AC催化剂催化甲醇水蒸气重整的性能

本文研究Co掺杂Mo_2C/AC(AC为活性炭)催化剂的催化甲醇重整制氢性能。利用粉末X线衍射仪(XRD)、比表面积分析仪和扫描电子显微镜(SEM)对Co掺杂Mo_2C/AC催化剂进行分析表征。结果表明:适量Co的掺杂可以提高甲醇水蒸气重整后产物中H_2的含量和甲醇转化率,掺杂1%Co时催化剂活性最高。在焙烧温度为725℃,负载量为10%时,催化甲醇水蒸气重整制氢效果最佳。当反应温度为450℃,甲醇溶液质量分数10%,液时空速为2 h-1时,甲醇转化率接近100%,催化产物中H2约占70%,CO控制在1%左右。     

富氧条件下In2O3／A12O3催化剂C3H6选择性还原NO

以碳氢化合物作为还原刑的选择性催化还原法(SCR)被认为是净化稀燃汽车尾气中NO的最有效途径之一．采用深胶—凝胶法制备了In2O3／Al2O3氧化物催化剂，对其进行了BET、XRD、XPS及TPD表征．在固定床反应器上用C3H6作还原剂，考察了不同焙烧温度，H2O及SO2对催化剂活性的影响．结果发现，催化剂的最佳焙烧温度为600℃，在反应温度为400℃时，NO最大转化率为95％．水蒸汽存在下，NO转化活性温度窗口向高温方向移动，NO最大转化率下降到90％，对应的反应温度为450℃．添加φ(SO2)＝0．009％后，催化剂在低于350℃的区间还原NO的活性得到一定程度的提高，表现出促进作用．当反应温度大于350℃后，催化活性明显下降，NO最大转化率下降到58％．     

流化床上甲烷催化转化制合成气Ni/SiO2催化剂性能研究

考察了流化床上Ni／SiO2催化剂对甲烷部分氧化和甲烷二氧化碳重整耦合反应的催化性能．研究了Ni负载量，反应温度、预还原温度对催化性能的影响．结果表明，镍基催化剂具有很高的初活性，但是在线反应6h后催化剂很快失活．TG、XRD和TEM分析结果显示高温下镍晶粒的聚集长大是催化剂活性显著下降的主要原因．     

完全液相法AlOOH催化甲醇脱水行为研究

用完全液相法制备了用于甲醇脱水合成二甲醚的羟基氧化铝催化剂,对催化剂进行活性评价,并与共沉淀法、溶胶凝胶法制备的催化剂进行了对比,用XRD、NH3-TPD、XPS、氮吸附等方法对催化剂进行了表征。活性评价结果显示,完全液相法制备的催化剂用于甲醇脱水反应,催化剂的诱导期较长,经过诱导期后甲醇转化率可以达到80%,与传统法相同热处理温度下制备的催化剂活性相当。XRD显示,经过500℃焙烧的催化剂以γ-Al2O3形态存在;但当热处理温度为300℃时,无论焙烧还是液相热处理,催化剂均以AlOOH形式存在。XPS结果表明,完全液相法制备的催化剂表面碳含量高于传统法制备的催化剂。NH3-TPD结果表明,完全液相法制备的催化剂表面强酸中心较多,与表面碳物种有关。反应过程中甲醇和二甲醚的洗脱作用使反应后催化剂表面的碳含量有所下降,弱酸中心增加,催化活性提高。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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