含介孔结构ZSM-5沸石分子筛的制备及其催化应用

先以硅烷偶联剂3 氨丙基三乙氧基硅烷（APTES）为软模板剂, 用软模板法制备含介孔结构的ZSM-5沸石分子筛; 然后用Fourier变换红外光谱(FT-IR)、 X射线衍射(XRD)、 N₂吸附脱附及透射电镜(TEM)等方法对制备的样品进行表征, 考察APTES添加量对合成样品孔结构的影响; 最后用模型反应苯酚分析其酸催化性能.     

SnO_2-SBA-15介孔分子筛的制备与表征

首先以P123、正硅酸乙酯为原料合成了SBA-15介孔分子筛,然后利用氯化亚锡的水解反应在SBA-15介孔分子筛表面及孔道内部沉积纳米SnO_2,对其进一步功能化,成功制备出了SnO_2-SBA-15介孔分子筛.采用多晶X射线衍射(XRD)、傅里叶变换红外光谱分析、同步热分析、氮气吸脱附等技术手段对材料的结构组成进行了表征,结果表明纳米二氧化锡成功负载到了SBA-15介孔分子筛表面和孔道内部.     

三聚氰胺热解产物的特性分析

以有机物三聚氰胺为初始原料, 在真空条件下使其热解（1 000 K）. 采用X射线衍射（XRD）、 透射电子显微镜（TEM）、 X射线光电子能谱(XPS)、 化学元素分析（EA）和傅里叶红外光谱(FT-IR) 分析样品的形貌、 成分和结构. 结果表明, 在真空条件下, 三聚氰胺全部分解, 分解产物为片层石墨相C₃N₄.      

干胶-水蒸汽辅助晶化法合成多级孔ZSM-5分子筛

采用干胶-水蒸汽辅助晶化法,通过优化制备条件,合成了粒径约80 nm的表面多孔纳米球形ZSM-5.考察了结构导向剂质量分数、硅源、铝源、沉淀剂种类、晶核形成时间及老化温度对纳米ZSM-5晶体形貌的影响.采用X射线衍射(XRD)、傅里叶变换红外光谱(FT-IR)、N_2物理吸附-脱附及透射电子显微镜(TEM)等表征手段对合成的分子筛进行了表征.结果表明:结构导向剂的质量分数、铝源的类型和晶核形成时间均能明显影响分子筛晶体形貌;结构导向剂质量分数的降低有助于提高ZSM-5微孔结构的长程有序性;优化合成条件可制备出具有约介孔2 nm、比表面积357.1 m~2/g、由80 nm的晶粒堆积形成的多级孔ZSM-5分子筛材料.     

特定酸度条件下的有序介孔SiO_2的制备与表征

采用水解缩合法在不同酸度条件下制备了介孔SiO2材料,研究了特定酸度条件下有序介孔SiO2的制备条件及不同酸度对有序介孔SiO2孔径大小的影响,并通过小角X-射线衍射(XRD)、傅立叶变换红外光谱(FT-IR)、透射电镜(TEM)和扫描电镜手段对制备的样品进行了表征.结果表明,控制酸度范围可以得到所需孔结构的有序介孔SiO2纳米材料,最佳酸度条件为1~2 mol/L,0.01 mol/L~0.5 mol/L时,介孔有序度降低,孔径变大,小于0.001 mol/L时,SiO2介孔消失.     

介孔分子筛Ti—AIMSU—Y后合成法制备及其催化性能

以介孔分子筛AlMSU-Y为载体,钛酸四丁酯、二氯二茂钛、四氯化钛为钛源,采用合成后嫁接法合成了3种Ti-AlMSU-Y介孔分子筛样品．用傅立叶变换红外光谱（FT-IR）、X射线粉末衍射（XRD）、N2吸附-脱附、固体核磁（MASNMR）、紫外一可见漫反射（UV_vis）和能谱（EDS）进行了表征,并以环己醇氧化反应考察了样品的催化性能．实验结果表明,样品Ti-AlMsU-Y仍保持了基体A1MSu—Y介孔孔道结构,钛原子进入分子筛骨架且以骨架四面体钛的形式存在,同时分子筛中非骨架铝的含量相对减少．在环己醇氧化反应中,骨架四面体Ti和骨架四面体A1存在明显的协同作用,表现出较高的催化活性．3种Ti—AIMSU-Y样品中,以钛酸四丁酯为钛源制得的样品Ti（z）-AIMSU-Y对环己醇的催化活性最好,在80℃反应24h,环己醇转化率为43．1％,环己酮选择性为100％．     

铁柱撑蒙脱石表面介导的Fe(Ⅱ)还原体系对邻硝基苯酚的高效去除

通过引入铁氧化物并煅烧处理对蒙脱石进行优化设计,成功合成了铁柱撑蒙脱石复合催化剂(FPMt).采用X射线衍射(XRD)、热重分析(TG)、透射电子显微镜(TEM)、傅里叶变换红外光谱(FT-IR)、N2吸附-脱附(BET)等分析方法对FPMt样品结构与表面性质进行表征,以邻硝基苯酚(2-NP,22μmol/L)作为代表...     

尿素辅助模板法合成介孔氮掺杂CeO2及其CO2捕获应用研究

以硝酸铈为前驱物,以尿素为助剂,采用一种简单的模板法合成了介孔氮掺杂CeO₂材料.利用X射线衍射仪(XRD)、吸附-脱附仪(BET)、透射电子显微镜(TEM)和傅里叶变换红外光谱(FT-IR)等设备对合成材料进行表征.多种测试结果证明:试验得到的纳米材料具有均一的介孔结构和较高的比表面积(124.8 m²·g^-1)并掺杂了氮元素.同时,测定了介孔CeO₂材料对于CO₂的吸附性能,并研究了氮掺杂对CeO₂材料的CO₂吸附性能的影响.结果表明:相比未掺杂氮的介孔CeO₂,氮掺杂的介孔CeO₂具有更好的CO₂吸附性能和循环吸附脱附性能.     

新型介孔材料的热及水热稳定性

以柠檬酸为成孔剂, 正硅酸乙酯为硅源, 硫酸铝为铝源, 在水热条件下合成一种新型介孔硅铝材料, 并采用X射线衍射（XRD）和透射电镜（TEM）对样品进行表征. N₂吸附 脱附结果表明, 新型介孔材料在1 173 K的高温条件下焙烧5 h以及在沸水中分别处理48,96,192,288 h后, 样品依然保持较好的介孔结构, 表明样品具有较好的热及水热稳定性.     

含Nb介孔Al2O3分子筛的合成及其性质研究

将过渡金属元素Nb嵌入介孔Al2O3中以期改变Al2O3表面酸性。以三嵌段共聚物P123为模板剂,无水AlCl3和草酸铌为前驱物,在乙醇溶剂中采用溶胶-凝胶法合成含Nb介孔Al2O3分子筛,并用X-射线粉末衍射(XRD)、傅里叶变换红外光谱(FT-IR)、低温氮气吸附-脱附等方法对其结构进行表征,采用Hammett指示剂法对其表面酸量、酸强度分布进行表征。结果表明,Nb嵌入介孔Al2O3骨架中,形成Nb-O-Al键,改变了介孔Al2O3分子筛孔径,使表面出现了较强的酸中心,提高了表面酸强度和总酸量。     

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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