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。     

对微孔AlPO_4-5分子筛水热合成中部分影响因素的研究

微孔磷酸铝分子筛AlPO4-5是一种具有代表性的磷酸盐分子筛,其优良的催化性能已得到广泛的肯定.其凝胶的组成直接影响到产品的组成和性质.以三乙胺为模板剂,拟薄水铝石、分析纯磷酸为原料,180℃下晶化36 h水热合成AlPO4-5分子筛.并以X-射线粉末衍射(XRD)对其进行结构鉴定、电子显微技术对其进行形貌表征.分别考察了水量改变、模板剂量改变及水量和模板剂量同时改变对AlPO4-5分子筛合成的影响.     

生物催化中固载酶的高效载体MCM-41的低温合成与表征

以正硅酸乙酯为硅源,十六烷基三甲基溴化铵为模板剂,氢氧化钠为碱源,在碱性条件下合成了纯硅超大孔分子筛Ｓｉ ＭＣＭ ４１;以四水合二氯化锰为锰源在酸性条件下合成了锰硅超大孔分子筛Ｍｎ ＭＣＭ ４１;并用Ｘ射线衍射(ＸＲＤ)、傅立叶变换红外光谱(ＦＴ ＩＲ)、透射电子显微镜(ＴＥＭ)等手段对其进行了表征·低温常压下在酸性介质中合成的ＭＣＭ ４１分子筛比在碱性介质中合成的ＭＣＭ ４１结晶度高、孔径大,更适合作为酶的载体·ＴＥＭ照片显示Ｓｉ ＭＣＭ ４１的粒径为０１μｍ,已达到超微分子筛的粒径范围·     

一种合成大孔径SBA-15介孔分子筛的新方法

通过加入无机盐硝酸铵辅助合成大孔径介孔分子筛SBA-15,用小角X-射线粉末衍射(SAXS)、透射电子显微镜(TEM)、N_2吸附脱附等手段对分子筛进行了表征.结果表明:合成的大孔径分子筛SBA-15具有高度有序的介孔结构,孔径约12 nm,比表面积894 m~2·g~(-1),孔容为2.6 cm~3·g~(-1);不加硝酸铵则不能得到具有高有序度的介孔材料.     

新显色剂TAMB分光光度法测钯的研究

研究了2-(2-噻唑偶氮)-5-二甲基氨基苯甲酸(TAMB)与钯的显色反应,其灵敏度为4.68×10~4dm~3·mol~(-1)·cm~(-1),反应具有良好的选择性,用于分子筛、蒙脱土、钢样及某些合成样品的测定,获得了令人满意的结果。     

氮化改性的SAPO-34分子筛的MTO性能研究

为了提高SAPO-34分子筛的低碳烯烃选择性級抗结焦性能,以三乙胺为模板剂,在正磷酸-拟薄水铝石-氢氟酸体系中合成了小粒径SAPO-34分子筛;以氨为氮源,采用高温氮化法对分子筛进行了改性。以XRD、NH3-TPD、BET等手段对分子筛样品进行了表征;在固定床反应器上测定了SAPO-34分子筛对MTO反应的催化性能。结果表明,添加氢氟酸有利于提高SAPO-34分子筛的结晶度,并且得到小而均匀的分子筛,其比表面积、孔体积分别由318m2/g、0.187 cm3/g增大到456 m2/g、0.294 cm3/g;经氮化改性后SAPO-34分子筛表面的酸强度及酸量减小,从而使其催化性能得到改善,烯烃选择性提高(乙烯+丙烯总选择性由70.91%提高到85.55%),尤其是乙烯选择性提高(乙烯/丙烯由1.58提高到1.87),催化剂的抗积碳性能提高(>6.5h),催化剂寿命也延长(>6.5h)。     

CoAPO-5分子筛的结构表征及其催化氧化特性研究

利用三乙胺(TEA)为有机模板剂,在水热体系中合成了具有不同Co含量的杂原子微孔磷铝分子筛CoAPO-5,并通过XRD、ICP、TG、N2吸附、UV-Vis DRS、H2-TPR和O2-TPO等技术对CoAPO-5分子筛的结构、过渡金属的存在状态以及氧化还原性等进行了表征和揭示.结果表明,所合成的CoAPO-5具有典型的AlPO4-5微孔分子筛结构,n(Co)/n(P)比小于0.1时结晶度较高;分子筛原粉中存在四配位的Co(Ⅱ),经焙烧可部分氧化为催化活化中心Co(Ⅲ),Co(Ⅱ)和Co(Ⅲ)在连续的氧化还原循环过程中可逆,且骨架Co物种的含量对CoAPO-5分子筛的结构及其氧化性能有较大的影响.     

模板剂用量对微波水热法制备ZSM-5分子筛的影响研究

以四丙基氢氧化铵(TPAOH)为模板剂,采用微波水热法制备ZSM-5分子筛。考察模板剂用量对微波水热法合成ZSM-5分子筛物化性质的影响,采用XRD、BET、SEM、NH3-TPD等手段对合成样品的微观结构、孔结构及表面化学性质进行分析表征,在MTO工艺中评价合成分子筛的催化性能。结果表明:模板剂用量对合成ZSM-5分子筛晶相组成、微观形貌、比表面积、孔径分布及表面酸性质具有较大的影响。改变模板剂用量会影响分子筛结晶度和孔结构,可通过模板剂用量调控制备不同酸性质ZSM-5分子筛。模板剂用量为n(TPAOH)∶n(Si O2)=0.35时,ZSM-5分子筛孔结构和表面酸性适中,形貌规整,MTO催化性能最佳,甲醇转化率为98.4%,低碳烯烃收率为75.39%。     

MeAPO-5(Me=Fe、Co、Mn)分子筛的制备、表征及催化环己烷氧化性能

以拟薄水铝石、正磷酸、九水合硝酸铁、硝酸锰、四水合乙酸钴为原料,三乙胺(Et3N)为模板剂,水热晶化法合成了一系列具有不同金属质量分数的FeAPO-5、CoAPO-5和MnAPO-5分子筛.采用XRD,UV-Vis,SEM及氮气物理吸附-脱附等手段对分子筛的结构、形貌以及金属原子在分子筛骨架中的存在状态进行了表征.结果...     

三种新偶氮安替比林显色剂的合成及分析应用

合成 3种新的偶氮安替比林显色剂 :5 - (4-安替比林偶氮 ) - 8-羟基喹啉 (AAHQ)、1- (4-安替比林偶氮 ) - 2 -萘酚 (AANP)和 3,6 -二 (4-安替比林偶氮 ) - H酸 (AAHA)。分析其与 5种金属离子的显色反应 ,建立了 AAHQ测定微量 Cu( )的新方法 ,其摩尔吸光系数ε为 1.6 7× 10 4 L· mol- 1 · cm- 1 ,Sandell灵敏度为 0 .0 0 38μg.cm- 2 ,Cu( )在 0～ 30 μg/ 2 5 ml范围内符合比耳定律。方法用于生物样中 Cu( )的测定 ,结果满意     

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

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     

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