Hβ沸石上甲苯歧化和C_9芳烃烷基转移反应

:研究了不同表面酸度的 Hβ沸石上甲苯歧化和 C9芳烃烷基转移反应。结果表明 :随 Hβ沸石表面酸度增加 ,甲苯转化率逐渐增大 ,C9芳烃转化率先增大后逐渐下降 ,芳烃总转化率先增大后趋于稳定 ;苯和二甲苯选择性随表面酸度增加而逐渐下降 ,产物中的 C 1 0 芳烃量逐渐增多 ,反应产物中甲乙苯、三甲苯异构体比例偏离热力学平衡值 ,二甲苯异构体比例与热力学平衡值一致。反应产物中二甲苯与苯间的摩尔比均大于 4 ,Hβ沸石具有优异的甲苯或苯与 C9芳烃烷基转移性能。     

Hβ沸石上甲苯和C_9芳烃歧化与烷基转移反应

研究了不同表面酸度的 Hβ沸石上甲苯和 C9芳烃歧化与烷基转移反应。结果表明 :随 Hβ沸石表面酸度增加 ,甲苯转化率逐渐增大 ,C9芳烃转化率先增大后逐渐下降 ,芳烃总转化率先增大后趋于稳定 ;苯和二甲苯选择性随表面酸度增加而逐渐下降 ,产物中的 C 10 芳烃量逐渐增多 ,反应产物中甲乙苯、三甲苯异构体比例偏离热力学平衡值 ,二甲苯异构体比例与热力学平衡值一致。反应产物中二甲苯与苯之摩尔比均大于 4,Hβ沸石具有优异的甲苯或苯与 C9芳烃烷基转移性能。     

Hβ沸石上甲苯歧化和C9芳烃烷基转移反应

研究了不同表面酸度的Ｈβ沸石上甲苯歧化和Ｃ９芳烃烷基转移反应。结果表明：随Ｈβ沸石表面酸度增加,甲苯转化率逐渐增大,Ｃ９芳轻转化率先增大后逐渐下降,芳烃总转化率先增大后趋于稳定;苯和二甲苯选择性随表面酸度增另而逐渐下降,产物中的Ｃ１０芳烃量逐渐增多,反应产物中甲乙苯,三甲苯异构体比例偏离热力学平衡值,二甲苯异构体比例与热力学平衡值一致。反应产物中二甲苯与苯间的摩尔比均大于４,Ｈβ沸石具有优异的甲苯     

N,N-二乙基甲酰胺与C6-C8芳烃二元混合溶液体系的体积性质研究

利用振动管密度计在 2 98.15K下测定了 N,N-二乙基甲酰胺 (DEF)分别与苯、甲苯、对二甲苯、间二甲苯、邻二甲苯、乙苯、苯乙烯构成的二元溶液体系的过量摩尔体积 (Vm E) ,在全部浓度范围内 ,Vm E均为负值 ,|Vm E (极值 ) |和 |Vm E(x =0 .5) |大致有如下顺序 :苯乙烯 >甲苯 >对二甲苯 >苯 >邻二甲苯≈乙苯 >间二甲苯 .实验结果表明 DEF分子与芳烃分子之间有相当强的相互作用 .     

神东煤粉粒流化床催化热解特性研究

采用等体积浸渍法制备Ni/γ-Al_2O_3(Ni的负载量9%,质量分数)和Ce-Ni/γ-Al_2O_3(CeO_2和Ni的负载量分别为2%和9%,质量分数)催化剂,并通过XRD,BET,H_2-TPR和NH_3-TPD对催化剂进行表征分析,以轻质芳烃苯、甲苯和二甲苯为目标产物,利用自主设计与搭建而成的粉-粒流化床快速热解实验装置,探究神东煤的催化热解特性。结果表明,无催化剂下,焦油中BTX质量分数为1.52%,单环芳烃质量分数为4.96%;在Ni/γ-Al_2O_3催化剂作用下焦油中BTX质量分数提高了29.61%,达到2.69%,单环芳烃质量分数增加了2.14倍,达到15.55%;在Ce-Ni/γ-Al_2O_3催化剂作用下焦油中BTX质量分数提高了76.97%,达到2.99%,单环芳烃质量分数增加了1.80倍,达到13.88%;Ce的加入可以使得Ni颗粒更加分散,同时抑制由于Ni颗粒聚集而产生强的酸位点,从而提高其催化活性。     

紫外线作用于氨基酸的电子自旋共振波谱

各种氨基酸粉末状样品在室温下经主要波长为2537A的紫外光照射,一般均能得到相当稳定的共振吸收波谱。紫外辐射的含硫氨基酸形成与RS·自由基有关的ESR信号,某些含硫氨基酸的紫外线信号与γ-射线信号类似,另一些含硫氨基酸在两种辐射条件下产生完全不同的波谱。与电离辐射结果不同,不含硫脂肪族氨基酸除亮氨酸外,经紫外线作用后一般产生幅度不大,无明显超精细结构的ESR信号。酪氨酸、色氨酸等环状氨基酸受紫外线作用后得到宽度稍有不同的单峰信号。     

黄酮类化合物清除对苯半醌负离子自由基研究(Ⅰ)

以对苯半醌负离子自由基为模型 ,利用ESR技术研究黄酮类化合物清除自由基的作用 ,初步获得一些构效关系。     

1,3,5-三甲苯联产1,2,4,5-四甲苯生产工艺的研究

开发了异构化和烷基化反应联合生产高纯1,3,5－三甲苯联产1,2,4,5－四甲苯的新工艺,确定了异构化和烷基化反应的最佳工艺条件,主要研究了三甲苯异构化的初始反应速率,化学反应平衡和烷基化反应对甲乙苯的消除作用,在此基础上,提出了以混合芳烃为原料进行异构化和烷基化反应联合法生产1,3,5－三甲苯联产1,2,4,5－四甲苯的新工艺。此工艺已实现了1,3,5－三甲苯600t／年的工业化生产,产品纯度为98．5％,效益显。     

降低卷烟烟气中多环芳烃和自由基的中药添加剂

研究了降低卷烟烟气中多环芳烃和自由基的中药添加剂。通过正交实验优化条件提取有效成分为添加剂 ,采用邻苯三酚自氧化紫外方法和荧光法筛选中药 ,得几种中草药的复方 ,喷洒于烟丝卷制成烟支后 ,利用电子自旋共振波谱仪 ( ESR)及气相色谱 /质谱法 ( GC/MS) ,对卷烟焦油中多环芳烃和焦油及烟气中自由基含量进行测定分析。实验结果表明 ,该添加剂对卷烟焦油中多环芳烃和焦油及烟气中的自由基含量具有良好的降低作用     

ππ电荷转移络合物的理论研究

用量子化学CNDO/2方法对顺丁烯二酸酐与甲苯、苯、丁二烯和异戊二烯的电子施受络合物的构象进行了研究。结果表明,最稳定的络合物构象是相互作用的两个分子平面互相平行的重叠式,平面间距在0.165～0.178nm之间。构象优化的能量极小对应着电荷转移的极大,因此,在电子施受络合物中,电荷转移起着决定性作用。计算的络合物的稳定性与络合常数的实验值的顺序一致。     

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

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.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Jane Eyre——A Feminist In The 19th Century

In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.     

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-