PMS改性淀粉对滑石粉悬浮体的絮凝作用及机理的研究

本研究了在几种条件的影响下，PMS对滑石粉悬浮体的絮凝努力学曲线的影响，发现对絮凝能力来说，各种条件都存在一个最佳区域，即PMS取代度为0．02－0．04，PMS加入量为25－40mg,pH值为大于5。另外从大分子形态和分散相表面电性质出发。对结果进行了讨论，认为PMS改性淀粉对滑石粉悬浮体的絮凝机理符合高分子絮凝剂“桥架”机理模型。     

无机高分子复合絮凝剂的制备及絮凝性能研究

制备无机高分子絮凝剂＿硅钙复合型聚合氯化铝镁锌(SCPAMZC),考察了不同pH值条件下水玻璃的胶凝时间,SiO2/Al(硅铝比),Mg/Zn,Ca/Zn,Ca Mg Zn/SiO2等因素对其絮凝性能的影响,确定了最佳制备条件为pH值2～4,SiO2/Al为1/0.7左右,Mg/Zn和Ca/Zn分别为1,Ca Mg Zn/SiO2为0.3。经应用实验表明:SCPAMZC用于印染废水和生活污水处理,具有优异的絮凝性能。     

聚硅硫酸铁絮凝剂的制备与性能

研究了无机高分子复合絮凝剂——聚硅硫酸铁(PFSiS)的制备与絮凝性能，考察了SiO2浓度、Fe／Si(摩尔比)、pH值及硅酸活化时间对PFSiS絮凝性能的影响。通过对模拟废水浊度的测定，检验了各种条件下的絮凝效果。结果表明：ωSiO2＝0．014—0．020，Fe／Si为0．8-1．0，pH值1．5-1．8，硅酸活化时间在l-8h，可获得絮凝性能优异的PFSiS。将PFSiS用于实际废水样品处理，获满意效果。     

煤矸石制PACS及其性能研究

本文提出了一种以煤矸石为主要原料制备聚硫氯化铝（简称ＰＡＣＳ）的新方法，并研究了影响ＰＡＣＳ性能的主要因素。实验结果表明，当（摩尔比）为１４～１６，碱化度为６５％～７０％，ｐＨ值为６～９时，ＰＡＣＳ的絮凝效果最佳。     

高Al_b含量聚合氯化铝的制备及其絮凝性能的研究

采用快速二次加碱法,通过Al-Ferron逐时络合比色法测定溶液中铝的形态分布,以Alb含量为衡量指标,探索了制备PAC的最佳条件.并对影响PAC絮凝性能的因素进行了初步研究.结果表明,该方法可制备出AlT0.5 mol.L-1,Alb含量高于93%的PAC溶液.且当pH值为7.1,投加量在3.0×10-4mol.L-1左右时,PAC的絮凝效果最佳,CODCr和浊度去除率分别高达94.5%和99.1%.     

几种聚硅酸铝铁(PSAF)絮凝剂的性能比较

聚硅酸金属盐絮凝剂性能优良。本文用铝和铁的硫酸及盐酸盐通过共聚法获得了几种不同的聚硅酸铝铁。通过实验得到了各自的最佳絮凝性能的水解度值。然后对最佳产品进行不同浊度和水体酸度的絮凝性能比较,并且对它们性能上的差异作了简单分析。     

微生物絮凝剂产生菌筛选及絮凝条件优化

从空气和活性污泥中筛选出絮凝剂产生菌,并对其絮凝条件进行优化研究。实验共分离纯化出纯种菌株19株,经絮凝试验筛选得到有絮凝能力的菌株9株,复筛得到3株絮凝活性较高且稳定的菌株,分别命名为M-2、M-3、G-3。以M-3为例,研究了碳源、氮源、培养基初始pH值、培养时间、培养温度及通气量等对菌株絮凝性能的影响,结果表明玉米面、黄豆面分别为最佳碳源和氮源,M-3的最佳培养条件为：温度30℃,培养基初始pH值为8．5,培养时间为36或60小时,摇床转速为160r／min。     

复配型高分子絮凝剂对含油污水的絮凝性能研究

本文采用有机高分子阳离子聚丙烯酰胺和无机高分子聚硅进行复配,研究了复配高分子絮凝剂在不同温度、pH值以及不同时间下对模拟油田污水的絮凝性能,并应用于现场污水的絮凝实验.结果表明,阳离子聚丙烯酰胺同聚硅复配时,离子度对复配絮凝剂絮凝性能影响较大,其中中高离子度的聚丙烯酰胺与聚硅在1：20配比条件下,复配后絮凝性能较好处理后污水的透光率达90%以上.     

γ辐射法制备壳聚糖接枝共聚物及其絮凝性能

以壳聚糖(Cts)和甲基丙烯酸(MAA)为原料,应用γ射线辐射引发技术进行接枝共聚反应,制备了壳聚糖与甲基丙烯酸的接枝共聚产物(Cts-g-MAA),采用搅拌实验和测浊度法研究接枝改性壳聚糖对铅锌选矿废水的絮凝效果,其中考察了废水pH值、Cts-g-MAA的质量浓度、快速搅拌速度、慢速搅拌时间、静置时间对絮凝效果的影响,并将其与壳聚糖的絮凝能力进行了对比.实验结果表明,废水的pH值、絮凝剂质量浓度、搅拌速度、搅拌时间和静置时间均对絮凝效果产生影响,其最佳絮凝条件为pH值8.5、Cts-g-MAA浓度1.2mg/L、搅拌强度300 r/min、慢速搅拌时间为10 min、静置时间为11 min,此条件下的浊度去除率达98.6%.接枝改性壳聚糖的絮凝效果好于壳聚糖,且絮凝时的用量明显低于壳聚糖.     

以四甲氧基硅为前驱体的溶胶-凝胶材料研究

以四甲氧基硅（TMOS）为前驱体制备了SiO2溶胶－凝胶材料，研究了pH值，温度以及H2O与TMOS的摩尔比等因素对水解－缩聚体系凝胶时间的影响；利用红外光谱法对材料进行了结构表征；采用差示扫描量热法和紫外－可见光谱法考察了溶胶－凝胶材料的热性能和光学性能，并用扫描电子显微镜观察了其微观结构。结果显示：SiO2溶胶－凝胶材料具有优良的热稳定性和光学性能；pH值对溶胶－凝胶材料的微观结构影响较大。     

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