在Fe_2O_3－K_2O催化剂上乙苯程序升温脱附研究──探讨乙苯脱氢反应机理

乙苯在Ｆｅ＿２Ｏ＿３－Ｋ＿２Ｏ催化剂上的ＴＰＤ研究表明，新鲜催化剂表面有α和β两种活性位，均具脱氢、脱乙基和裂解活性．乙苯吸附后能脱氢生成苯乙烯和脱乙基生成苯，若预先吸附水亦可脱甲基生成甲苯，新鲜催化剂表面氧化能力较强，脱下的的氢或烷基会立即与表面晶格氧作用生成Ｈ＿２Ｏ和ＣＯ＿２，并致使催化剂表面被还原产生新的γ活性位．γ位裂解性能较强，但在吸附水后也具有脱氢和脱烷基活性，水对甲苯的生成起着重要的作用，α活性位可能是Ｋ＿２Ｆｅ＿２Ｏ＿４相，β和γ位可能是Ｆｅ＿２Ｏ＿３和Ｆｅ＿３Ｏ＿４（部分还原的氧化铁）相．     

丙烯氨氧化催化剂物化性能研究：Ⅱ.催化剂失活前后的结构表征

采用ＸＲＤ，ＩＲ，Ｍｏｂａｕｅｒ ＥＳＲ，ＸＰＳ，ＳＥＭ和孔结构分析等分析测试手段，对比研究了新鲜，失活和再生三种丙烯氨氧化催化剂的体相结构和表面性质。结果表明，新鲜催化剂中各元素以Ｆｅ２（ＭｏＯ４），α－ＣｏＭｏＯ４，ＮｉＭｏＯ４，γ－Ｂｉ２Ｏ３．ＭｏＯ３，α－Ｂｉ２Ｏ３．３ＭｏＯ３，η－ＭｏＯ３，α－Ｂｉ２Ｏ３和β－Ｂｉ２Ｏ３形式存在２；失活催化剂中，部分Ｆｅ２（ＭｏＯ４）３转变为α－Ｆｅ－Ｍ     

H(PyH)_3[Mo_2O_4(C_2O_4)_2(H_2O)_2]_2·2H_2O的晶体结构

Ｈ（ＰｙＨ）_３［Ｍｏ_２Ｏ_４（Ｃ_２Ｏ_４）_２（Ｈ_２Ｏ）_２］_２·２Ｈ_２Ｏ的晶体结构采用。射线衍射法测定．晶体属单斜 晶系，空间群Ａ２／ｍ，ａ＝９．１１４（８）、ｂ＝１８．９４５（６）、Ｃ＝１１．４３（２）Ａ，＝１０２．３（１），Ｚ＝２，Ｄｅａｌｃ ＝２．０９，Ｄｏｂｓ＝２．０８。ｇ·ｃｍ－３。研究表明，络合物具有双氧桥双核钼Ｍｏ２Ｏ４２＝核心，Ｍｏ－Ｍｏ金属键长２．５６４Ａ．Ｍｏ为扭歪的八面体配位，二聚体由两个用的配位多面体通过共边相联系，络阴离子具有Ｃ２对称性。     

异核有机金属配合物［dpeNi］［FcCOSCH_2CO_2］NO_3的合成及性质研究

［ｄｐｅＮｉ］［ＦｃＣＯＳＣＨ_２ＣＯ_２］ＮＯ_３是黄绿色晶体，溶于ＣＨ_２Ｃｌ_２，石油醚等有机溶剂。它可由α—二戊铁基硫代乙酸［ｄｐｅＮｉ］［ＦｃＣＯＳＣＨ_２ＣＯ_２Ｈ］和ｄｐｅＮｉＣｌ_２［Ｐｈ_２ＰＣＨ_２ＣＨ_２·ＰＰｈ_２］ＮｉＣｌ_２及ＴＩＮＯ_３经长时间搅拌生成，ＩＲ谱表明，配合物金属Ｎｉ（Ⅱ）分别和ｄｐｅ中磷，ＦｃＣＯＳＣＨ_２ＣＯ_２Ｈ中硫及羧基中氧结合形成四配位双五员环平面正方形结构。ＣＶ法研究表明Ｎｉ（Ⅱ）氧化态呈多样性变化。     

甲烷作为化工原料直接转化生成芳烃和乙烯新催化过程的研究：———？…

采用程序升温表面反应方法研究甲烷在Ｍｏ／ＨＺＳＭ－５催化剂上的反应过程,在反应初始阶段发现有Ｈ２Ｏ,ＣＯ２和ＣＯ生成。随着这些产物的消失,乙烯和苯和含量达到最大值。认为在反应初始阶段,甲烷与催化剂发生氧化还原相互作用形成新的活性相,从而使甲烷催化转化为乙烯苯。活性相的形成需要Ｍｏ和ＨＺＳＭ－５同时存在。当Ｍｏ含量为２％￣３％时,对生成乙烯和苯最为有利。     

氧缺位铁酸锰分解CO_2成C的研究

空气氧化湿法制备的ＭｎＦｅ２Ｏ４在Ｈ２还原下，生成氧缺位铁酸锰ＭｎＦｅ２Ｏ４－δ（０＜δ＜１），利用ＸＲＤ和Ｍｏｓｓｂａｕｅｒ谱等技术，对它的性质（还原性，晶格常数稳定性）进行了详细地研究，考查了在氧缺位铁酸锰（ＭｎＦｅ２Ｏ４－δ，δ＞１）及ＭｎＯ－ＦｅＯ固溶体下ＣＯ２分解成Ｃ的活性，结果表明（ＭｎＦｅ２Ｏ４－δ，δ＞１）能够有效地分解ＣＯ２成Ｃ，并且在反应以后自身转变成了化学计量的ＭｎＦｅ２Ｏ４，ＭｎＯ－ＦｅＯ分解ＣＯ２以后，一部分变为ＭｎＦｅ２Ｏ４，一部分仍然保持ＭｎＯ－ＦｅＯ固溶体结构     

CoFe－γ－Fe_2O_3磁粉Hc增大机理的研究

本文从实验与理论上探讨了ＣｏＦｅ－γ－Ｆｅ＿２Ｏ＿３磁粉的矫顽力Ｈｃ增大的机理，其原因在于包钴包亚铁后，同内核γ－Ｆｅ＿２Ｏ＿３相比较，表面晶格结构发生变化，产生了较强的表面单轴各向异性所致。     

可调谐激光材料－掺杂铝酸铍单晶的生长及其光谱特性

先使用烧结法合成掺杂铝酸铍（ＢｅＡｌ_２Ｏ_４）多晶体，然后采用熔盐法从三元系熔剂中生长出掺ｃｒ^３＋和Ｔｉ^３＋的ＢｅＡｌ_２Ｏ_４单晶。通过控制熔剂成份的摩尔比，溶质与混合溶剂的配比以及降温速率，获得尺寸分别为１０ｍｍ×５ｍｍ×４ｍｍ和８ｍｍ×４ｍｍ×３ｍｍ的透明Ｃｒ（３＋）：ＢｅＡｌ_２Ｏ_４和Ｔｉ^３＋：ＢｅＡ１_２Ｏ_４单晶。并讨论了它们的光谱特征和激光性能。     

纺锤形铁黄α－FeOOH微晶合成动力学研究

本文对纺锤形α－ＦｅＯＯＨ微晶合成动力学过程进行了研究．利用复相反应经验动力学方程，考察了初始浓度、反应温度和空气流量对Ｆｅ（ＯＨ）２－ＰｅＣＯ３悬浮液氧化速率的影响，确定了α－ＦｅＯＯＨ成核－生长速率方程，证实了晶粒生长阶段存在溶解－氧化的动态平衡，根据活化能大小，推断相界面氧化反应为该复相反应的控制步骤，还对α－ＦｅＯＯＨ成核生长微观机理作了初步探讨．     

MTPP－CeO_x－SiO_2催化NO_x还原

在密闭循环反应器中，于２９０℃下研究了ＣＯ存在下催化剂ＭＴＰＰ－ＣｅＯ＿ｘ－ＳｉＯ＿２（Ｍ＝Ｃｏ￣（２＋）、Ｎｉ￣（２＋）、Ｃｕ￣（２＋））催化还原ＮＯ或Ｎ＿２Ｏ的反应。催化ＮＯ还原的活性顺序是ＮｉＴＰＰ＞ＣｏＴＰＰ＞ＣｕＴＰＰ，而Ｎ＿２Ｏ还原和ＮＯ深度还原为Ｎ＿２的顺序是ＮｉＴＰＰ＞ＣｕＴＰＰ＞ＣｏＴＰＰ。ＮＯ＿ｘ还原的催化特性和ＭＴＰＰ的电化学氧化机理有关（取决于中心金属或卟啉环被氧化的次序）。ＣＯ不仅还原ＮＯ＿ｘ而且还促进载体Ｃｅ＿２Ｏ＿３物种的形成。探讨了ＮＯ催化还原的机理。     

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     

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

正~~     

Brief Introduction to “Journal of Jilin University( Science Edition) ”

<正>"Journal of Jilin University(Science Edition)"is a comprehensive academic journal in the fields of science sponsored by Jilin University and administrated by the Ministry of Education of the Peoples Republic of China.The journal started publication in 1955.The original name at starting publication was"Journal of Natural Science of Northeast People University",which was changed into"Acta Scientiarum Naturalium Universitatis Jilinensis"in 1958 owing to the name change of the university.The present journal name has