聚四氟乙烯微孔膜表面亲水改性研究

用化学法对PTFE微孔膜表面进行亲水改性,利用红外光谱（ATR—FTIR）和扫描电镜（SEM）观察了改性膜表面形态和微观结构的变化,FTIR图表明膜的表面产生了极性基团,SEM图显示膜的孔径和孔隙率发生了变化。研究了钠萘处理液浓度与膜改性效果的关系,结果表明：随着钠萘处理液浓度的提高,膜表面接触角减小,亲水性增强。钠萘处理液浓度以0．6mol／L为最佳。     

聚乳酸膜表面氨等离子体改性

为研究氨等离子体对聚乳酸膜表面进行改性以及改性时发生的化学变化，采用接触角和XPS来表征．实验结果表明，氨等离子体能对聚乳酸膜表面进行改性，氨主要以-NH-CO-或C-N和-NH3^ 基团形式接枝在聚乳酸膜表面的链段上，并且随着等离子体处理时间从5min延长到20min，聚乳酸膜表面N元素的含量也从3.2％增加至5.2％(P=80W，而接触角则随聚乳酸膜表面接枝上亲水性极强的-NH3基团含量而变化．     

氩等离子体射流对聚四氟乙烯表面改性的研究

采用氩等离子体射流对有机材料聚四氟乙烯(PTFE)进行表面改性,通过接触角测量、扫描电子显微镜(SEM)观察、X射线光电子能谱(XPS)和衰减全反射红外光谱(ATR-FTIR)分析,以及表面电阻率和沿面闪络电压等参量的测量,研究了等离子体射流处理前后PTFE的表面特性。实验结果表明:氩等离子体射流产生的粒子主要有OH、N*、Ar和少量的O。PTFE经大气压氩等离子体射流处理后,其表面水接触角下降,表面粗糙度变大,表面突起和裂痕显著增加,且表面有新的含氧基团生成;增加表面改性时间,表面改性效果会达到饱和状态;另一方面,表面改性后的PTFE存在微弱的老化效应,当在空气中放置10d后,其表面水接触角为66.2°,仍然低于表面处理前的值。由于等离子体改性使PTFE表面形态及化学成分发生变化,粗糙度增加,使PTFE表面电阻率降低,导致其沿面闪络电压升高。     

NH3等离子体处理的PET表面接枝氨基酸的研究

用氨气等离子体处理聚对苯二甲酸乙二醇酯（PET）膜，在表面引入活性基团氨基，并通过戊二醛接枝谷氨酸。利用接触角、全反射傅里叶红外光谱（ATR-FTIR）、光电子能谱（XPS）和体外血液相容性实验(APTT)表征接枝改性后的膜的表面结构和性能，比较了只用氨气等离子体处理的膜和接枝谷氨酸后的膜的性能。结果表明，两种改性膜亲水性均提高，70W放电功率下改性的膜血液相容性改善效果最好。与未处理的膜相比，用氨气等离子体处理的膜的APTT延长了5.9s,接枝了谷氨酸的膜的APTT延长了3.2s。     

低温等离子体表面改性提高聚四氟乙烯黏结性能

探究不同气体氛围、等离子体放电功率和处理时间对聚四氟乙烯(polytetrafluoroethylene,PTFE)表面黏附性和亲水性的影响,以表征其黏结性能。使用场发射扫描电子显微镜(field emission scanning electron microscopy,FE-SEM)和X射线光电子能谱(X-ray photoelectron spectroscopy,XPS)表征分析PTFE膜黏结性能改善的机理。结果表明,等离子体处理能提高PTFE膜的表面亲水性,经不同气体等离子体处理后PTFE表面黏附性均有显著提升。FE-SEM分析表明PTFE膜表面粗糙度增加,这是促使其黏结性能提升的原因之一;XPS显示等离子体处理后PTFE膜表面引入新的含氧、含氮基团,这是黏结性能提升的主要原因。     

基于有限元方法的CF/PTFE复合材料界面应力

经表面改性和未经改性的碳纤维（CF）增强聚四氟乙烯（PTFE）复合材料的弹性强度均随着碳纤维含量的增加而增强．以碳纤维增强聚四氟乙烯（CF／PTFE）复合材料弯曲强度试验结果作为依据,开展CF／PTFE复合材料界面应力的研究工作．采用各向异性等参单元,推导出在平面载荷作用下多层纤维增强复合板的层间应力分布．进一步利用有限元方法对CF／PT—FE复合材料的界面进行应力分析,并得到与试验结果相一致的结论．     

铁氧体构成磁控管的磁场分析及它对PET表面改性的影响

在铁氧体磁场存在的情况下,通过研究涤纶膜（PET）表面的碳氟等离子体的改性效果受磁场的影响,讨论了带电粒子的行为及磁场对改性的影响．结果发现：磁场的存在使得PET表面的聚合区域向刻蚀区域位移,且主要依赖于磁场的强度．     

聚四氟乙烯的表面改性及粘接性能研究

采用Ar等离子体技术对聚四氟乙烯(PTFE)片材表面预处理,再用热接枝的方法引发甲基丙烯酸缩水甘油酯(GMA)对其表面进行接枝改性.考察不同等离子体处理条件及接枝单体体积分数对PTFE与钢粘接强度和与水接触角的影响.同时,对接枝后的PTFE用x射线光电子能谱(XPS)进行分析表征.研究结果表明,GMA单体成功地接枝到PTFE表面,当等离子体处理时间为5min、功率为50W、气氛压力为50Pa、单体接枝体积分数为20%时,改性后的PTFE与钢的拉剪强度由处理前的24.6N·cm-2增加到处理后的284.6N·cm-2.     

利用远程Ar等离子体引发聚四氟乙烯膜接枝丙烯酸的研究

利用远程Ar等离子体对聚四氟乙烯(PTFE)膜进行预处理,与空气接触氧化后接枝丙烯酸(AA).用碘化钠法测定膜表面过氧基团的浓度,探讨等离子体放电时间和功率对膜表面过氧基团浓度的影响,以及过氧基团浓度对接枝率的影响.通过接触角测定分析了接枝PTFE表面的亲水性变化,利用衰减全反射傅里叶变换红外光谱(ATR-FTIR)和X射线光电子能谱图(XPS)对接枝膜进行结构表征.研究结果表明:在放电功率为100 W、放电时间为100 s和氩气流量为20 cm3/min的条件下,过氧基团浓度为2.87×1013个/cm2;过氧基团越多,越有利于AA在PTFE表面发生接枝反应;随着接枝率的增加,PTFE表面接触角呈下降趋势.     

二氧化硫等离子体处理聚乙烯膜表面及抗凝血性能

目的 研究等离子改性低密度聚乙烯（ＬＤＰＥ）膜表面的抗凝血性能,方法 用二氧化硫（ＳＯ２）气体等离子体处理ＬＤＰＥ膜表面,通过接触角预测,研究磺酸基与表面浸润性,表面自由能之间的关系．用ＸＰＳ能谱,ＡＴＲ－ＦＴＩＲ对表面组成及结构进行表征,体外凝血试验分析抗凝血性能。结果 ＳＯ２气体等离子体处理ＬＤＰＥ膜表面,可使磺酸基与ＬＤＰＥ表面分子共价结合,获得了具有抗凝血性能的表面分子结构。结论 ＳＯ２气     

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     

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     

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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