硬脂酸和氧化锌促进的CPE／NBR自硫化反应

在ＣＰＥ／ＮＢＲ共混物中加入氧化锌和硬脂酸后能显著促进硫化反应，提高硫化速度及交联密度，硬脂酸和氧化锌用量对ＣＰＥ／ＮＢＲ共混物的反应性和物理性能显著影响，当硬脂酸用量大于３份，氧化锌用量大于１份时，可得到综合性能良好的硫化胶，此外硫化温度和时间也影响自硫化共混物性能，该体系较适宜的硫化条件是１７０℃和３０ｍｉｎ，用硬脂酸和氧化锌促进的ＣＰＥ／ＮＢＲ自硫化共混物具有硫化速度快和硫化胶凝胶含量高的优     

PVC／SBR共混型热塑性弹性体的研究

主要介绍了增容剂的种类、用量对非相容性ＰＶＣ／ＳＢＲ共混体系改性的研究，并讨论了硫化剂、促进剂用量，返炼次数对共混体物性，挤出性能的影响。试验结果表明：ＮＢＲ－２６是ＰＶＣ／ＳＢＲ的优良增容剂，可以显著改善共混物的力学性能。通过对硫化剂、促进剂的适当选择，共混物可获得良好的综合性能。     

PVC／NBR／SBS三元共混物的形态结构与性能

本文通过冲击试验、动态力学分析（ＭＭＡ）、透射电镜（ＴＥＭ）和扫描电镜（ＳＥＭ）观察，研究了聚氯乙烯／丁腈橡胶／苯乙烯。丁二烯。苯乙烯嵌段共聚物（ＰＶＣ／ＮＢＲ／ＳＢＳ）三元共混物的形态结构和性能，并且讨论了两者之间的关系。ＮＢＲ－２９对ＰＶＣ和ＳＢＳ有较好的增容作用，与ＳＢＳ一起对ＰＶＣ有协同增韧效应。     

自硫化反应动力学的研究

以氯丁橡胶（ＣＲ）和羧基丁腈橡胶（ＸＮＢＲ）共混物为例，考察了硫化温度、时间对自硫化共混物凝胶含量（Ｇｃ）的影响．自硫化反应在很短时间内（１８５°Ｃ×５ｍｉｎ或１６０°Ｃ×１０ｍｉｎ）就达到很高的Ｇｃ．提出用Ｇｃ－ｔ曲线确定自硫化的正硫化时间；用橡胶体积分数（φｒ）表征自硫化橡胶交联密度，自硫化反应发生在两种橡胶的官能团之间，反应符合二级反应动力学．利用两个反应温度下的反应速率ｋ计算出自硫化反应的活化能Ｅａ．采用Ｅａ计算出不同温度下的ｋ值，可以预测出不同温度和时间的φｒ值．实验表明，φｒ的预测值和实验值较符合．     

PVC／SBS共混体系的增容技术研究

借助反应性挤出接枝的方法，在ＰＶＣ／ＳＢＳ动态硫化过程中引入顺丁烯二酯矸（ＭＡＡＮ），“就地”产生增容，以改装ＰＶＣ与ＳＢＳ间的相容性。用ＩＲ，ＳＥＭ，ＤＳＣ和力学方法对ＰＶＣ／ＳＢＳ共混体系进行表征，结果表明：此过程可以获得满意的共混效果，可以实现工业化生产．     

提高聚氯乙烯与丁苯橡胶共混相容性的研究

通过加入各种增容剂（Ｃｏｍｐａｔｉｂｉｌｉｚｅｒ）和采用粉末丁苯橡胶（ＰＳＢＲ）及经接枝、交联改性的粉末丁苯橡胶（ＰＭＳＢＲ），研究了提高聚氯乙烯／丁苯橡胶（ＰＶＣ／ＳＢＲ）共混相容性的途径。物理机械性能测试结果表明：五种增容剂对软质ＰＶＣ／ＳＢＲ共混物的改性效果以粉末丁腈Ｐ８３和丁腈－２６（ＮＢＲ－２６）最佳；粉末橡胶对ＰＶＣ的改性效果优于块状橡胶，ＰＭＳＢＲ对软质ＰＶＣ的改性效果优于以ＮＢＲ－２６作增容剂的块状ＳＢＲ和ＰＳＢＲ；用不同改性方法制得的四种ＰＭＳＢＲ中，以多层乳液接枝改性的ＰＭＳＢＲ－４对ＰＶＣ的改性效果最佳，用它改性硬质ＰＶＣ的缺口抗冲击强度和软质ＰＶＣ的耐寒性，效果皆超过粉末丁腈Ｐ８３。扫描电镜、透射电镜和动态力学谱分析表明：ＰＶＣ／ＰＭＳＢＲ－４共混材料呈良好的韧性断裂，橡胶粒子分散较均匀，相界面模糊，低温Ｔｇ升高，说明ＰＶＣ／ＳＢＲ的相容性获得显著提高     

PA／PP塑料合金的研制

研究了ＰＡ／ＰＰ合金体系的制备和力学性能，结果表明，加入马来酸酐对ＰＰ进行接枝改性后，与ＰＡ共混可以提高合金体系的力学性能。当引入第三组分ＥＰＤＭ或ＮＢＲ组成三元体系ＰＡ／ＰＰ／ＥＰＤＭ或ＰＡ／ＰＰ／ＮＢＲ，可以大幅度提高合金体系冲击强度，且三元组分ＰＡ／ＰＰ／ＥＰＤＭ与ＰＡ／ＰＰ／ＮＢＲ的力学性能接近，可以用ＮＢＲ替代ＥＰＤＭ混入ＰＡ／ＰＰ合金体系中，降低产品成本。     

PVC／NBR／PE反应性共混体系的研究

通过共交联反应使ＰＶＣ／ＮＢＲ－３１／Ｐ共混体系的相容性增加，机械性能得到改善，ＤＳＣ结果表明，交联使ＰＥ的结晶受到破坏，熔点下降。ＤＭＡ也证明交联增进了相应相互作用，使ＰＶＣ的Ｔｇ下降，ＰＥ的Ｔｇ上升，由于交联改变了共混体系的形态结构，使其冲击强度提高了一倍多。     

SBS与CPE熔融共混的研究

研究了ＳＢＳ（苯乙烯─丁二烯─苯乙烯嵌段共聚物）及ＳＢＳ／ＣＰＥ（氯化聚乙烯）共混体系的流变学行为。探讨了不同类型的ＳＢＳ，ＳＢＳ／ＣＰＥ比例、ＣＰＥ含氯量、增粘剂和增塑剂的含量等因素对粘接性能的影响。结果表明：ＳＢＳ／ＣＰＥ共混体系对ＰＶＣ人造革的粘接有正协同效应，并可以得到熔融粘度比ＳＢＳ小、而粘接力比ＳＢＳ大的热熔性压敏胶粘剂。     

MBS和PVC／MBS的形态,结构与性能

本文研究了三元共聚物ＭＢＳ树脂和ＰＶＣＮＢＳ共混物的形态、结构及其相关性能。采用间歇加料法得到形态规整的核壳型树脂。改变三元组分比例和玻璃化转变温度（Ｔｇ）能大大影响ＰＶＣ增韧效果，当Ｂ＝４２％时Ｓ：Ｍ＝（３４～３０）：（２４～２８）为宜。ＤＳＣ测定结果表明：ＰＶＣ与ＭＢＳ的壳层ＰＭＭＡ能很好相容，从二相间的相容结构形态证实，共混物间形成良好的粘合界面层，通过透射电镜（ＴＥＭ）和扫描电镜（ＳＥＭ）观察到ＰＶＣＮＢＳ共混体系由脆性转变为韧性的结构形态和形貌特征，抗冲击值可由纯ＰＶＣ时的４ｋＪ／ｍ２增到ＭＢＳ１５份时的５０ｋＪ／ｍ２以上。     

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.     

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     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

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

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