不同相对分子质量的APAM的制备及其动力黏度性质研究

以丙烯酰胺(AM)为原料合成了不同相对分子质量的聚丙烯酰胺(PAM).通过碱性水解反应制备了阴离子聚丙烯酰胺(APAM).采用胶体滴定法测定了APAM的水解度,考察了碱的用量、聚合物的相对分子质量对水解度的影响.探讨了温度、pH值、相对分子质量和水解度等因素对APAM动力黏度的影响,并根据实验结果进行了应用实验.研究结果表明:当酰胺基与碱的比例在1∶3时聚合物水解度达到60%,增加碱的用量,其最终水解度保持不变;水解度60%的APAM在温度为25℃、pH=8～10、相对分子质量172×104时的动力黏度达到13 400 mPa·s,将它应用于涂料中,其黏度从57 mPa·s上升至299.5 mPa·s.     

新型耐温抗盐聚合物增黏剂的合成及性能评价

以丙烯酰胺(AM)和阳离子单体二甲基二烯丙基氯化铵(DMDAAC)为原料,在交联剂N,N'-亚甲基双丙烯酰胺和水溶性偶氮引发剂存在的条件下,采用溶液聚合法合成了阳离子型水凝胶。根据高分子间异性电荷静电相吸的分子复合原理,将阳离子型水凝胶溶液与阴离子型HPAM溶液复配成复合型聚合物。对复合型聚合物的增黏、耐温、热稳定、耐盐和剪切流变性进行了评价。结果表明,阳离子型水凝胶溶液的加入可以提高HPAM溶液的黏度,当阳离子型水凝胶溶液和HPAM溶液质量浓度均为2 000 mg/L、阳离子度为5%、体积比为1∶1时,其增黏效果最好。25℃时,在剪切速率为170 s-1的条件下,黏度由单一HPAM溶液的31.1 mPa·s增加到复合溶液的46.8 mPa·s。研究表明,复合溶液具有良好的耐温、耐盐性能,其热稳定和剪切流变性能都得到了明显的改善。     

聚合物溶液黏度对PDMS/PVDF复合膜微结构及渗透汽化性能的影响

采用不同黏度的聚二甲基硅氧烷(PDMS)溶液制备平板聚二甲基硅氧烷/聚偏二氟乙烯(PDMS/PVDF)复合膜,并比较膜对乙醇/水混合物的渗透汽化性能的影响。通过扫描电子显微镜(SEM)、接触角分析仪等表征手段研究聚合物溶液黏度对膜微结构的影响。结果表明:聚合物溶液黏度为90 mPa·s时制备的复合膜分离性能最佳,当进料温度为313 K时,膜对5%乙醇水溶液的通量可达761 g/(m2·h),分离因子为9.1。     

等粘度聚合物溶液对驱油效果影响研究

通过室内物理模拟实验,设计等黏度驱替实验中两种不同相对分子质量(1.9×107和2.5×107)聚合物溶液的黏度为78.9mPa·s(45℃下),对比了两者的黏弹性及其在等速注入和恒压注入下的驱油效果。实验结果表明,在等速注入和恒压注入,通过降低聚合物相对分子质量提高聚合物溶液浓度保持聚合物溶液黏度不变,低分子量高浓度方案化学驱采收率比高分子量低浓度方案提高近一个百分点;以等速方案最高压力恒定注入方案的化学驱采收率最高;在注入PV数相等时,相同黏度的两种不同聚合物交替注入驱方案驱油效果要优于这两种聚合物整体段塞驱方案。     

疏水缔合聚合物溶液性能及其驱油效果

针对胜利油田高温高盐的油藏环境,设计合成了一种具有梳型结构的疏水缔合聚合物,系统考察了该聚合物溶液的增黏性、耐温抗盐性、长期稳定性、注入性和驱油效果。实验结果表明,随着浓度的增加,溶液黏度呈指数增长,增黏性强。在高温高盐条件下,该疏水缔合聚合物溶液黏度均比常规聚丙烯酰胺溶液高,表现出优异的耐温抗盐性能。在90℃条件下,随老化时间增加,溶液黏度先增加后降低,60 d后溶液黏度值大于40 mPa·s,表现出优异的长期稳定性。随注入量增加,压力先增加后趋于平衡,达到0.5 MPa,表明其注入性良好。当注入浓度一定时,随着注入倍数的增加,提高原油采收率幅度先增大后趋于稳定;当注入倍数一定时,随疏水缔合聚合物浓度的增加,提高采收率幅度增大。     

电渗析回用聚驱污水为配聚用水的试验研究

由于大庆油田聚驱污水的矿化度较高(约4 000 mg/L),其中大量的K 、Na 、Ca2 、Mg2 等阳离子能引起聚合物较大的黏度损失,所以聚合物只能用低矿化度清水配制.选用电渗析来降低聚驱污水的矿化度,通过小型电渗析的现场试验,证明电渗析对矿化度的去除率可达90%以上,能显著改善聚驱污水的配聚性能,并且处理后的低矿化度聚驱污水能够达到或超过清水的配聚效果,从而可以代替清水用于现场配制聚合物溶液驱油;此外要使聚驱污水达到和清水一样的配聚效果,电渗析的脱盐能耗只为0.95 kW.h/m3,低于购买清水的价格,是一种经济有效的降矿化度技术,适用于处理聚驱污水.     

生化法处理油田采出水用于配聚保黏的技术研究

将油田采油污水处理后替代清水用于配制聚合物溶液,既节约淡水资源,又减少污水外排.以胜利油田某区块采出水为研究对象,采用生物氧化和生物竞争抑制集成工艺,有效去除污水中的硫酸盐还原菌及硫化氢等还原性物质,使处理后的污水直接用于配制聚合物溶液.室内和现场试验结果表明:该工艺对污水COD去除率达65％以上,对硫化氢等还原性物质去除率达100％,且有效抑制SRB的活性.用处理后的污水配制的聚合物溶液黏度维持在20 mPa·s以上达20 d,达到聚驱生产要求.     

高浓度聚驱采出污水降粘室内实验

目前高浓度聚合物驱注入2 500万分子量的超高分聚合物,严重影响水处理效果。用降黏剂对高浓度聚合物驱采出污水进行降黏处理。当污水pH值为7—8,温度20—35℃,降黏剂加药量为30 mg/L,沉降时间90 min时对含聚污水进行降黏处理后。污水中的聚合物浓度由570 mg/L降低到10 mg/L,聚合物去除率达98.2%;黏度由2.0 mPa.s降低到1.0 mPa.s,降黏率为83%。     

新型耐盐蠕虫状胶束体系的性能和驱油效果研究

利用两性表面活性剂十六烷基磺基甜菜碱(HDAPS)、阴离子表面活性剂十二烷基硫酸钠(SDS)和助剂在高盐条件下制备两种蠕虫状胶束体系,即HDAPS-SDS体系和HDAPS-SDS-0.2%助剂混合体系,研究体系的黏弹性能、降低油水界面张力性能和驱油效果。结果表明,质量分数为0.73%的HDAPS-SDS体系所形成的蠕虫状胶束在60℃时黏度为42.3 mPa·s,与原油界面张力最低值为6.0×10-2mN·m-1;加入0.2%助剂后,0.73%HDAPS-SDS体系的黏度提高到51 mPa·s,并可与原油达到6.7×10-3mN·m-1的超低界面张力;两种新型蠕虫状胶束具有流度控制和降低油水界面张力的双重作用,具有较好的驱油效果。     

聚丙烯酰胺降解菌的筛选及降解性能评价

油田聚合物驱的大面积推广应用导致聚合物驱产出水中含有大量的聚丙烯酰胺(PAM),含聚丙烯酰胺的产出液外排将对环境造成很大的危害,回注将对油层产生致命性伤害.从含聚丙烯酰胺的废水中初步筛选到一株以聚丙烯酰胺为碳源的降解菌,命名为PM-1.经生理生化鉴定,初步确定为芽孢杆菌属(Bacillussp.).实验结果表明:在温度为35℃,pH值为7.5的条件下,降解5d,500mg/L聚丙烯酰胺溶液的降解率最高可达到38.4%.     

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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