阳离子聚丙烯酰胺微乳液的制备及其絮凝性能研究

以甲醛、二甲胺和丙烯酰胺为原料,通过Mannich反应首先合成阳离子单体N-(二甲氨基)甲基丙烯酰胺,然后用反相微乳液聚合制得不同阳离子度的阳离子聚丙烯酰胺乳液(CPAM).通过探讨反应过程的影响因素,确定了最佳的制备工艺,并对制成的产品进行了性能研究.当反应温度50℃,物质的量比n(丙烯酰胺)∶n(甲醛)∶n(二甲胺)=1∶1.2∶1,反应时间为2 h时,制备的阳离子单体可使乳液聚合的产品获得最佳的阳离子度.通过正交实验反映了单体质量分数、引发剂质量分数、油水相体积比以及反应温度对聚合反应的影响.结果表明,当单体质量分数为30%,引发剂质量分数为0.8%,油水相体积比1.2∶1,反应温度40℃时产品的絮凝效果最佳.在常温、酸性条件下,CPAM对硅藻土的絮凝效果良好.     

紫外引发合成三元阳离子聚丙烯酰胺及其对雌酮的絮凝去除

通过紫外引发聚合技术制备了具有疏水特性的三元阳离子聚丙烯酰胺,并用于典型环境雌激素雌酮(E1)的分离和去除。由丙烯酰胺(AM)、丙烯酰氧基乙基三甲基氯化铵(DAC)和丙烯酰氧基乙基二甲基苄基氯化铵(AODBAC)单体合成三元共聚物(PADA),并采用傅里叶变换红外光谱(FT-IR),核磁共振氢谱(~1H NMR)和热失重/差示扫描量热仪(TG/DSC)分别对聚合物的结构和热分解性能进行表征。FT-IR和~~1H NMR结果表明聚合物成功合成。通过引入疏水性基团(苯基),TG/DSC分析观察到PADA热稳定性能提高。在最佳条件下(p H=7,絮凝剂用量为4.0 mg/L),用高效絮凝剂PADA-3(阳离子度为40%,特性黏度为6.30 d L·g~(-1))得到最佳E1絮凝性能(E1去除率90.1%,絮凝体积18.3μm,絮凝动力学22.69×10~(-4)s~(-1))。Zeta电位和絮体尺寸分析用于探究E1去除的絮凝机理。结果表明,E1去除过程中,电中和、吸附和架桥效应占主导地位。     

壳聚糖-铁絮凝剂的制备及其絮凝性能

利用无机嵌入有机的方式改性壳聚糖制成壳聚糖-铁絮凝剂,使用高岭土悬浊液对其絮凝性能进行了考察。结果表明,当壳聚糖-铁絮凝剂（CTS-Fe）的投加量为5mg/L,m（CTS）∶m（Fe）=2∶1,pH=7时,絮凝效果最佳,沉降率为88.75%。并对壳聚糖-铁絮凝剂、壳聚糖、聚合氯化铁和壳聚糖-聚合氯化铁复合絮凝剂对高岭土悬浊液的处理效果进行了对比研究。结果表明,壳聚糖-铁絮凝剂的处理效果最好,且用量较少。     

基于压裂废水处理的三元两性聚合物絮凝剂的合成及性能

利用一种新的阳离子单体3-丙烯酰氧基-2-羟丙基三甲基氯化铵(AHPTAC)与丙烯酰胺(AM)和2-丙烯酰氨基-2-甲基丙磺酸(AMPS)通过水溶液聚合得到一种三元两性共聚物絮凝剂P(AM-AHPTAC-AMPS)(PAAA),将PAAA与聚合氯化铝铁(PAFC)复配用于处理两种压裂废水,并比较评价其与阳离子聚丙烯酰胺(CPAM)的絮凝性能。结果表明:合成PAAA的最适宜条件为AM、AHPTAC和AMPS的物质的量之比为1∶3∶2、单体总用量占反应体系的质量比为20%、复合引发剂VA-044与(NH 4)2S 2O 8-NaHSO 3质量比为1∶1、复合引发剂用量占反应体系的质量比为0.2%、反应温度为55℃;PAAA/PAFC复合絮凝剂具有较好的絮凝性能,对胜利孤岛压裂废水及涪陵页岩气压裂废水的COD Cr去除率分别为55.5%和82.7%;对水溶性有机污染物质含量高的废水去除效果更优,COD Cr去除率比CPAM/PAFC提高26%。     

改性膨润土矿物材料制备试验

以提纯后的钠基膨润土为原料，采用四氧化三铁磁体合成磁性膨润土，通过改变合成过程中的pH值、 温度、 搅拌聚合时间以及改性剂用量，根据改性磁性膨润土吸附铜离子的效果，判断实验条件对改性磁性膨润土的影响. 确定最佳的改性条件为合成时pH值12，合成过程温度40℃，搅拌聚合时间2.5h，吸附时间60min，改性剂(n_Fe∶n_Si=3∶1)用量30%(质量分数），产品最佳循环利用次数4次. 通过扫描电镜、 透射电镜、 XRD和电子探针等对产品进行表征分析，结果表明改性膨润土具有较好的吸附能力，利用四氧化三铁复合可以制备出性能优良的磁改性膨润土.     

稠油炼化污水处理用聚合硅磷硫酸铁的制备

以硫酸亚铁为主要材料,通过添加活化硅酸等组分,制备了一种新型的聚合硅磷硫酸铁絮凝剂.确定了其制备过程中的影响因素并通过实验确定了最佳制备条件:硫酸亚铁质量分数为55%,硅酸钠质量分数为15%,亚铁与双氧水用量的摩尔比为1.2∶1,氧化温度40℃,氧化时间4 h,聚合温度60℃,聚合时间2 h.通过均匀设计实验确定了制备聚合硅磷硫酸铁絮凝剂最佳组分:铁硅摩尔比为5.0∶1,铁酸摩尔比为3.2∶1,铁磷摩尔比为18.0∶1.在实验室最佳条件下,用制备得到的絮凝剂对稠油炼化污水进行絮凝处理,油的去除率可达到94.1%.     

硫酸钡阻垢剂的制备及性能评价

以丙烯酸(AA)、衣康酸(IA)、丙烯酸甲酯(MAC)及2-丙烯酰胺基-2-甲基丙磺酸(AMPS)为单体,过硫酸铵为引发剂,采用水溶液自由基聚合法制备了IA/AA/MAC/AMPS新型四元聚合物阻垢剂。在单因素实验条件下分析单体配比、引发剂用量、聚合温度及反应时间对阻垢性能的影响,并运用正交实验研究合成新型阻垢剂的最佳反应条件组合。确定最佳合成条件为:IA/AA/MAC/AMPS 4种单体质量配比为2∶1∶1∶0. 75,引发剂质量为4种单体总质量的8%,聚合温度为80℃,反应时间为3. 5 h。利用静态阻垢法对所研制的阻垢剂进行阻垢效果评价,研究了阻垢剂质量浓度、温度、pH值对阻垢效果的影响。实验结果表明,阻垢剂质量浓度为80 mg/L时,阻垢率为80. 46%,对硫酸钡的阻垢效果最好;在温度为85℃时,阻垢率可达82. 87%;随着pH值的增加,阻垢率变化趋势较明显,在pH值呈中性的溶液中阻垢效果最好。利用红外光谱对共聚物的结构进行了表征,并确定该共聚物分子链中含有所引入的官能团。     

两性离子聚合物硅垢阻垢剂的合成及阻垢性能

采用水溶液自由基聚合法,引入一种新型烯丙基型季铵盐阳离子——三羟乙基烯丙基季铵盐,与丙烯酰胺、2-丙烯酰胺-2-甲基丙磺酸(AMPS)在氧化-还原引发剂体系下合成一种两性三元共聚物。在静态条件下考察最佳合成条件:单体配比n(季铵盐阳离子)∶n(丙烯酰胺)∶n(AMPS)为1∶2∶1,聚合温度为60℃、反应时间为4 h、引发剂质量分数为4. 5%时,合成的聚合物阻垢性能最好。性能评价结果表明,阻垢剂质量浓度为120 mg/L时,对硅垢的阻垢率可达到78. 2%。通过加入阻垢剂前后垢样的电镜扫描图可知,加入阻垢剂的垢样疏松分散。     

绿色阻垢剂聚天冬氨酸的优化制备

以马来酸酐为原料制备聚天冬氨酸,并对聚合反应的质量配比、聚合温度和聚合时间三个反应条件进行了优化实验,对最优条件下合成的PASP与其它阻垢剂进行了性能对比。结果表明:合成PASP的最佳条件是:原料质量配比为1∶1.1,聚合温度为160℃,聚合时间为1h,阻垢率可以达到95%以上,生物降解性能达到70%。     

壳聚糖复合絮凝去除水源水中有机物与铝离子的实验研究

研究了壳聚糖与无机絮凝剂的复合效果,实验结果表明,复合絮凝能够相互促进壳聚糖与无机絮凝剂各自的絮凝性能,显著提高浊度与有机物的去除效果.在壳聚糖絮凝剂分别与三种常用无机絮凝剂(硫酸铝、氯化铁和聚合铝铁)的复合絮凝的效果表明,其中聚合铝铁跟壳聚糖的复合絮凝取得了更好的效果,在最佳条件下,其浊度、CODMN和UV254的去除率分别达到了97%、44%和55%.另外,无论是壳聚糖单独使用还是与聚合铝铁复合使用,在最佳的情况下,都使出水中的残留铝浓度小于检测方法的检出限.     

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.     

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