由煤系高岭土原位合成NaY分子筛

以煤系高岭土为原料 ,经碱熔活化、补硅 ,在优化的合成条件下 ,可以原位水热合成NaY分子筛。详细考察了晶化温度、晶化时间、加水量、老化时间和合成体系中硅铝比等反应因子对合成产物的结构和热稳定性的影响。得出的最佳反应条件如下 :合成体系中硅铝经为 2 ,晶化温度 370K、晶化时间 10h、老化时间 12h、加水量 4 0～ 6 0mL。其中 ,晶化温度和加水量是影响结晶产物物理结构性能的主要因素。采用XRD、IR、N2 静态容量吸附法、DTA DTG等手段对结晶产物的晶态结构、比表面积及孔分布、热稳定性等进行了表征。结果表明 ,以高岭土为原料可以原位合成出结晶度较高、无杂晶的NaY分子筛。所得分子筛比表面积较高 (42 0m2 /g) ,孔径分布集中 (集中在 0 .6nm) ,热稳定性好。     

汽相转移法合成不同硅源的MCM-22分子筛

采用汽相转移(VPT)法合成出结晶度较高的纯MCM-22分子筛,并首次将硅酸钠应用于VPT法合成MCM-22分子筛;合成过程模板剂和Na⁺ 用量与水热合成法相比明显减少。用X射线衍射仪、扫描电子显微镜及BET比表面测定对产物作了表征,并重点对不同硅源对结晶产物的影响作了讨论.     

含钛电炉熔分渣制备4A分子筛及其吸附性能

以含钛电炉熔分渣提钛后的水浸液为原料,采用常压回流法和水热法分别合成了4A分子筛.在控制硅铝比(n(SiO2)/n(Al2O3)摩尔比)为2的条件下,系统探讨了水钠比(n(H2O)/n(Na2O)摩尔比)、反应时间和温度对合成4A分子筛物相和微观形貌的影响.当控制水钠比为80且反应时间为8 h时,采用常压回流法可以制备出尺寸均一且结晶完全的4A分子筛;而采用水热法在120℃条件下,3 h即可制备得到形状规则的4A分子筛.另外,探讨了水热法不同反应温度条件下制备的分子筛对硫酸铜溶液吸附性能的影响.结果表明:反应温度为120℃条件下合成的4A分子筛对铜离子的吸附效率最高,在150 min时其吸附率可达70%.     

PO_4~(3-)/Al-MCM-41介孔分子筛合成及表征

通过液晶模板机理合成了Al-MCM-41介孔分子筛,并用磷酸浸渍法制备PO43-/Al-MCM-41.通过X射线衍射(XRD)、氮气吸附-脱附、红外光谱、Hammett指示剂胺滴定等方法对所合成样品进行了表征.XRD和N2吸附脱附研究结果表明.PO43-/Al-MCM-41具有较规则的孔道结构.平均孔径3.10 nm,比表面积为560 m2/g.酸量滴定分析表明,PO43-/Al-MCM-41具有较强的酸性.     

高纯相X型分子筛的水热合成与表征

目的 合成高纯相X型分子筛,并对其进行了相关表征.方法 在不引入有机胺模板剂的条件下,通过水热法合成了X型分子筛;考察了反应温度、反应时间对合成X型分子筛的影响,并利用XRD,SEM等技术对所得产物进行了相关表征.结果与结论 优化了X型分子筛的合成条件,最终在100℃下晶化4h,得到了相应产物;通过XRD,SEM等技术对其进行了相关表征,证明所得产物为高结晶度、高纯相的X型分子筛.该分子筛具有明显的异向生长的特点,呈现出大面积暴露（111）晶面的正八面体结构.     

水热处理的HZSM-5分子筛的孔结构及活性研究

采用X 射线衍射 (XRD)、红外光谱 (IR)、NH3 TPD、真空重量吸附、静态吸附容量法以及正己烷的裂化反应等方法系统地研究了不同温度下用 10 0 %水蒸气处理的HZSM 5分子筛 (硅铝比为 2 5 ,直接法合成 )的结构、酸性、吸附性能和催化裂化性能。研究结果表明 ,随着水热处理温度的升高 ,HZSM 5分子筛的结晶度虽有下降趋势 ,但变化不显著 ,水热处理温度对正己烷吸附量的影响也不大 ,这说明水热处理后HZSM 5分子筛的结构没有发生明显的变化 ;随着水热处理温度的升高 ,HZSM 5分子筛的比表面积减小 ,二次孔或中孔有增大趋势 ,酸中心数目减少 ,活性降低 ,但其活性稳定性却较高。     

安徽钾长石资源概况及共烧结工艺探讨

我国是个严重缺钾的国家,安徽省钾长石矿资源储量大、品位高,易采易选,是非金属矿产资源之一,但尚未很好开发利用.国内外钾长石提钾工艺非常成熟,但还存在不足之处,现以宁国钾长石矿为主要原料,采用共烧结工艺提钾,研究钾长石共烧结温度、时间及添加剂CaCl2用量对钾溶出率的影响,从而确定共烧结工艺的最佳参数,即m(CaCl2)∶m(钾长石矿)≥0.809∶1,时间≥30 min,温度≥800 ℃,钾长石中K2O溶出率可达95%.     

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.     

高岭土为原料合成Y/MCM-41复合分子筛及其催化性能

以高岭土为原料,采用水热法合成了复合分子筛Y/MCM-41.采用X射线粉末衍射和氮气物理吸附等手段进行了表征,研究了各种因素对合成样品结构性能的影响,考察了该分子筛对苯酚与叔丁醇烷基化反应的催化性能.结果表明:120℃下水热反应24 h,成功合成了复合分子筛;复合分子筛具有介孔和微孔双重孔结构,比表面积为628.9 m2.g-1,平均孔径为2.73 nm;复合分子筛对苯酚与叔丁醇的烷基化反应具有良好的催化性能,最佳反应条件为n(叔丁醇)/n(苯酚)=2.0,空速为1.0 h-1,反应时间为1 h,反应温度为140℃,苯酚的转化率可达62.2%,4-叔丁基苯酚的选择性可达86.0%;反应温度对催化性能有明显影响,低温范围内升温有利于烷基化反应的进行,而温度过高时,脱烷基化反应为主要反应.     

乙醇-水体系中SAPO-5分子筛的合成与表征

目的合成SAPO-5分子筛,并对其结构进行表征。方法以三乙胺为模板剂,在乙醇-水体系中进行合成,考察了晶化时间、HF用量以及醇-水比例对合成SAPO-5分子筛的影响,并利用XRD,SEM,吡啶吸附FT-IR等技术对所得产物进行表征。结果合成了具有较高长径比(a/c)的SAPO-5分子筛。结论在醇-水体系中,在HF作用下,SAPO-5分子筛的结晶速度明显减缓;SAPO-5分子筛其长径比随醇-水比例改变发生明显变化,所得的SAPO-5分子筛产生了一定的BrΦnsted和Lewis酸中心。     

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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