甲壳质乙酰基脱除规律的研究

论述了甲壳质和壳聚糖的制备方法，着重研究了碱量、质量分布、反应时间及温度对甲壳质乙酰脱除率的影响。得到了甲壳质的乙酰基脱除规律和需要的最佳实验条件。结果表明，上述影响因素均有一个最佳范围。实际生产中应加以控制，其中以碱淮质量分率和反应温度对乙酰基脱除的影响最大。     

催化剂催化聚酯的大分子酰胺化反应制备尼龙6T

以聚对苯二甲酸乙二醇酯(PET)和己二胺为原料,在溶剂环丁砜中进行大分子酰胺化反应制备一种半芳香聚酰胺(尼龙6T)。研究了不同反应温度和催化剂用量分别与产品的反应产率、酯-酰胺基团的转化率和特性粘度的关系,得到制备较高产率、酯-酰胺基团的转化率和特性粘度的尼龙6T产品所需的最佳反应条件,并进一步研究了催化剂催化大分子酰胺化反应的作用。     

甲壳质乙酰基脱除规律的研究

论述了甲壳质和壳聚糖的制备方法。着重研究了碱量、质量分率、反应时间及温度对甲壳质乙酰脱除率的影响，得到了甲壳质的乙酰基脱除规律和需要的最佳实验条件。研究结果表明。上述影响因素均有一个最佳范围，实际生产中应加以控制，其中以碱液质量分率和反应温度对乙酰基脱除的影响最大，试验还证实，制备壳聚糖分离出的浓碱液可以循环使用，以降低生产成本。     

新型水性聚氨酯乳液的合成及其性能影响因素的研究

采用预聚法合成了一新型的水性聚氨酯乳液，研究了配方中异氰酸酯基和羟基的物质的量的比（-NCO／-OH）、反应温度、羧基含量对水性聚氨酯的粘度、粒径和吸水率等性能的影响。表明，随着-NCO／-OH比的增大，粘度下降，粒径增加，吸水率下降；预聚反应温度越高，越快达到异氰酸酯基的理论值，但是温度越高越易发生副反应；随着羧基含量的增加，粘度升高，粒径起初下降，最终趋于平衡，吸水率升高。     

双(2-苯并咪唑基)乙烷的合成工艺研究

以邻苯二胺和丁二酸为原料,在多聚磷酸存在下微波辐射得到双(2-苯并咪唑基)乙烷,考查了原料配比、温度、反应时间等条件对产率的影响.结果表明:胺酸物质的摩尔比为2.2:1、酰化反应温度180℃、酰化反应时间3.5 h、微波辐射时间10 min是最适宜的反应条件,其产率可达50.0%.     

新型水性聚氨酯乳液的合成及其性能影响因素的研究

采用预聚法合成了一新型的水性聚氨酯乳液,研究了配方中异氰酸酯基和羟基的物质的量的比(-NCO/-OH)、反应温度、羧基含量对水性聚氨酯的粘度、粒径和吸水率等性能的影响。表明,随着-NCO/-OH比的增大,粘度下降,粒径增加,吸水率下降;预聚反应温度越高,越快达到异氰酸酯基的理论值,但是温度越高越易发生副反应;随着羧基含量的增加,粘度升高,粒径起初下降,最终趋于平衡,吸水率升高。     

醋酸麦迪霉素合成工艺研究

对用麦迪霉素为原料直接合成醋酸麦迪霉素的工艺进行研究－ 用ＤＭＡＰ作酰化反应催化剂时,可以避免分子内异构化和过度酰化等副反应－ 考察了原料配比、反应温度、反应时间等因素对酰化产物收率的影响－ 用正交试验发现选择工艺条件为：麦迪霉素与乙酰氯的摩尔比１∶３ ．３,反应温度６０ ℃,反应时间１０ ｈ 时,酰化反应收率为９７ ．５ ％ ,经醇解后,反应总收率为８４％ － 具有良好的工业化前景－ 表３,参５－     

高粘度磷酸酯淀粉的工艺研究

以玉米淀粉为原材料、三聚磷酸钠为酯化剂、碳酰二胺为催化剂，半干法制备了高粘度磷酸酯淀粉。实验研究了pH值、碳酰二胺添加量、反应温度和反应时间对磷酸酯淀粉峰值粘度的影响，并通过正交实验选取最佳反应条件。Brabender曲线显示磷酸酯淀粉的糊化温度降低，而峰值粘度远高于玉米原淀粉。     

脂肪族双取代二酰二肼化合物的合成

选用了丁二酸二乙酯和戊二酸二乙酯为代表，在一定反应条件下合成酰肼，并以此为原料。用酸酐作为酰化剂，进一步合成了N，N′-二乙酰基丁二酰二肼、N，N′-二乙酰基戊二酰二肼和N，N′-二丙酰基戊二酰二肼三种酰基化的双酰肼，探索了实验最佳条件，并对所合成的化合物进行了表征．     

无毒增塑剂乙酰柠檬酸三丁酯的合成研究

以柠檬酸、正丁醇和乙酸酐为原料,经酯化、酰化两步反应合成乙酰柠檬酸三丁酯,考察了催化剂、原料配比、反应时间、温度等因素对合成反应的影响,确定最佳反应条件.     

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