N2O4-O3硝化取代芳烃时取代基上的P轨道的邻位协助作用

对N2 O4 O3 硝化取代芳烃进行广泛的研究 ,发现其产物的异构体分布与传统的混酸硝化产物的异构体分布有很大差别 ,并对造成这种差别的原因进行了分析。分析表明 ,取代基上的P轨道的邻位协助作用是主要因素 ,电子密度分布计算及试验结果支持这种解释     

N2O4—O3硝化取代芳烃时取代基上的P轨道的邻拉协助作用

对N2O4－O3硝化取代芳烃进行广泛的研究，发现其产物的异构体分布与传统的混酸硝化产物的异构体分布有很大差别，并对造成这种差别的原因进行了分析。分析表明，取代基上的P轨道的邻位协助作用是主要因素，电子密度分布计算及试验结果支持这种解释。     

长链烷基苯胺的合成及其清洁生产研究

以烷基苯为原料，采用硝化、催化加氢工艺合成了烷基苯胺，通过对合成影响因素的分析，提出了长链烷基苯胺合成的清洁生产办法。实验结果表明硝硫混酸反应体系的烷基苯转化率远大于其它反应体系，产物对邻比可达３．１９，而采用醋硝混酸等硝化剂则主要获得邻位硝化产物。采用催化加氢工艺消除了用铁粉或硫化碱还原的污染。用本清洁工艺生产长链烷基苯胺，原料和能源消耗少，产率高，污染少。     

酸性皂土催化剂上硝酸对烷基苯的区域选择性硝化

芳烃硝化反应研究的目的是建立更具有选择性的硝化方法，以满足环境质量发展要求，在酸性皂土固体酸催化下，应用硝酸硝化甲苯、等烷基苯时，能够提高烷基苯的地位选择性硝化能力，邻对硝化产物异构体比例分别为０．６０、０．３９、０．４２和０．１１较经典硝化方法结果明显降低。     

十二烷基苯硝化选择性的测定

利用对位异构体的对称性由核磁共振氢谱测定了工业十二烷基苯在硝硫混酸中的硝化选择性，发现一硝化产物中对位异构体的比例为７５％￣８０％。以月桂酸和苯为原料，经氯化、酰化和还原合成了正十二烷基苯。在同样条件下研究了正十二烷基苯的硝化，由核磁共振氢谱和气相色谱分析，发现一硝化产物中对位异构体的比例仅为６０％。根据空间位阻效应，对结果进行了讨论，并与甲苯，乙苯，异丙苯等短链烷基苯的硝化结果进行了比较。     

溶剂对取代苯乙酰化反应的导构体比例影响

以正戊酸为原料,经过酰化,还原制得正戊苯。正戊苯进行乙酰反应时生成邻正戊基苯乙酮和对正戊基工苯乙。酮。较详细地研究了六种溶剂：１,２－二氯乙烷,二硫化碳,四氯化碳,环守,正已烷,氯苯对产物异构体邻／对比例的影响。研究表明,四氯化碳,二硫化碳,１,２－二氯乙烷作溶剂时,产物正戊基苯乙酮的邻位异构体最少,对位异构体最多。     

精馏硝化法制造TNT新工艺中关于MNT—DNT真空精馏分离的研究

精馏-硝化法是把甲苯硝化成TNT的一种新工艺。 本工艺利用近代高效的金属丝网波纹填料分离MNT的三种异构体(邻一、间一、对一),然后用硝硫混酸把邻一或对一MNT硝化成军品TNT,这样可避免亚硫酸钠溶液精制TNT的工序。精馏-硝化法有三个目的: (a)消除红水(它是一种精制工序产生的污染物)。 (b)MNT多种多样的利用。 (c)军民结合。 本报告研究了关于MNT—DNT精馏分离中的安全问题。藉助于精馏操作基本原理及高效的金属丝网波纹填料的低阻力可设计一套分离装置。通过实验室的试验和在9395厂中间试验的发现,DNT在塔釜中的浓度可以突破美国专利3620928[1]提出的爆炸极限值(10％),即MNT-DNT的分离工艺是安全的。结果为精馏-硝化法扫除了技术上的障碍。     

在硝酸-硫酸-废酸条件下合成硝基氯苯的反应动力学研究

通过对硝基氯苯动力学的研究，为根据市场变化适时调节邻位、对位硝基氯苯的生产提供理论依据。氯苯硝化反应为液液相反应，在硝酸-硫酸-废酸体系中，研究了氯苯硝化反应的反应过程，根据反应传质情况推导了氯苯硝化反应的动力学模型，并通过实验测得了氯苯在上述体系中硝化反应的宏观动力学方程。     

在醋酐中硝化甲苯的研究

本文指出,在醋酐中硝化甲苯获得的硝基甲苯中含有2～3％的间—硝基甲苯。观察到硝基甲苯的异构体在-30～ 25℃的范围内随温度的变化规律。在—30℃下的硝化产物中分离出1.4—加合物,我们用红外、核磁共振光谱核对了1.4—加合物的结构,它受热分解为对甲苯醋酸酯。     

雌甾2-或4-衍生物的红外光谱鉴定

近年来,在雌甾改造合成中,当在芳香A环上进行硝化,酰化,卤化和氧化等反应时,由于3-位酚羟基的影响,常导致2-和4-两种异构体。用红外光谱法简便地鉴别雌甾2-或4-衍生物,及时地提供化学合成的信息,具有一定的实用意义。     

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

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