聚合氯化铝铁的性质与羟铁比的关系及其混凝除藻性能的研究

对聚合氯化铝铁溶液的pH值、可见光OD460、形态分布等性质随羟铁比BFe=[OH-] [Fe3+]的变化规律进行了研究。结果表明,BFe能有效地统一聚合氯化铝铁溶液中的铝铁比和碱化度两参数,且可以表征铝铁共聚物的聚合程度;BFe与铝铁多核羟基络合物的含量Mb呈一定的线性关系,BFe越大,Mb越大,混凝除藻效果亦越好。提出在聚合氯化铝铁的制备过程中BFe是一个至关重要的控制参数。只有当BFe>3时,铝铁体系中才能形成稳定的、高聚合度的铝铁共聚物。     

高岭土尾矿制备聚合氯化铝铁絮凝剂及性能研究

利用苏州高岭土尾矿制备聚合氯化铝铁絮凝剂,对聚合氯化铝铁的理化和电化学性能进行了分析检测.研究表明：pH＜8时,聚合氯化铝铁（PAFC）溶液均保持正电性.通过傅里叶红外光谱分析了产品的结构,研究了Zeta电位与COD除去率的关系,探讨其絮凝机理,并应用于实际印染废水的处理,取得了满意的效果.     

Ferron逐时络合比色法的改进实验研究

改进了经典的Ferron逐时络合比色法，使其能定量测定铝铁共存溶液的形态分布；分析了该实验方法中比色一缓冲溶液的成分和pH值的影响，确定以铝、铁与Ferron反应的等吸收点362nm为测定波长．实验表明，总浓度相同而铝铁比不同的铝铁共存溶液，与Ferron溶液反应后其吸光值都大致相等，且在实验浓度范围内符合朗伯一比尔定律．     

用铝酸钙粉制备聚合氯化铝铁絮凝剂的研究

以一种新的原料－－铝酸钙和盐酸反应制备聚合氯化铝铁，找出了最佳制备条件，并对其性能进行了考察。结果表明，碱基度、pH值对PAFC的絮凝性能有较大影响，当碱基度为75％左右，水样的pH值为7－9时，该产品的絮凝性能最佳。     

赤泥制备的聚合氯化铝铁处理高岭土废水

为回收赤泥中的铝铁成分,解决赤泥污染和占地问题,提出了利用赤泥制备聚合氯化铝铁(PAFC)的新方法.以废水中高岭土为处理对象,与聚合氯化铝(PAC)进行了混凝对比实验,考察了混凝剂投加量、废水pH值、废水浓度、废水温度、盐基度等因素对絮凝效果的影响.实验结果表明:混凝剂的投加量、废水pH值、盐基度、废水浓度等对混凝效果有明显影响,温度对混凝效果的影响较小,PAC最高去浊率为93%,PAFC最高去浊率达到96%.     

低温地表水高效除浊工艺

采用无机高分子混凝剂聚合氯化铝铁（PAFC）,并结合管式微涡混合器、网格反应池、小间距斜板沉淀池、快滤池组合而成的一体化净水装置,对北方地区低温地表水的除浊进行试验研究.试验结果表明,当混合时间为3s,PAFC投药量为60mg/L,反应时间10min,沉淀池上升流速高达3.5mm/s时,低温低浊及高浊地表水经本工艺净化后,水浊度依然小于2NTU,并可降低工艺投资及运行费用,具有明显的经济效益.     

两种铝盐混凝剂对不同原水最佳混凝效果研究

目的研究不同铝盐混凝剂对不同原水水质的混凝效果,并对其结果进行比较。方法取宝鸡渭河原水、清姜河原水为水样,以PAC和PAFC为混凝剂,分别进行最佳投加量和最佳pH的单因素混凝实验,选用混凝效果较好的PAFC进行正交实验,分析混凝后水样浊度与UV254。结果渭河原水中,PAC最佳投加量为4~8mL,PAFC最佳投加量为4~6mL,PAC的最佳pH值为6~8,PAFC的最佳pH值为5~8;在清姜河原水中,PAC的最佳投加量为2~8mL,PAFC的最佳投加量为2~6mL,PAC,PAFC的最佳pH值均为6~8。结论渭河原水浊度与UV254较高,混凝剂投加量比pH值更能影响高浊度原水的混凝效果;清姜河原水浊度与UV254较低,pH值比混凝剂投加量更能影响低浊度原水的混凝效果。PAFC混凝效果的影响因素依次为:搅拌时间、PAFC投加量、pH值;PAFC的混凝最佳操作条件为:PAFC的投加量为6mL,pH值为6,快速搅拌时间为60s。     

硅酸对聚铁溶液形态分布及转化规律的影响

针对聚铁硅絮凝剂的稳定性问题,研究了硅酸对Fe(Ⅲ)溶液水解的影响.实验结果表明:硅酸的存在使Fe(Ⅲ)水解溶液的pH弛豫特征产生了一定的改变,表现出低OH/Fe摩尔比时的阻聚效应和高OH/Fe摩尔比时初期的促聚效应,并使Fe(Ⅲ) 在溶液中的形态分布及转化特征发生了一定的改变.但硅酸的存在并不能使Fe(Ⅲ)水解溶液的形态分布及转化等化学特征发生根本性的改变.     

复合型生物絮凝剂去除低浊水源水中铝的研究

针对传统无机铝盐絮凝剂在处理低温低浊水时残余铝过高的问题,采用中试装置,应用复合型生物絮凝荆(CBF)处理北方地区冬季低温低浊水源水,考察了在不同混凝条件下处理后水中残余铝浓度的变化.结果表明:复合型生物絮凝剂对水中残余铝有很好的效果,在与聚合氯化铝铁复配进行强化混凝的试验当中,混凝效果提高36.1%,总投药量降低了15%,并且消除了聚合氯化铝铁(PAFC)导致的残余铝升高的现象,出水残余铝浓度仅为0.016 mg/L.综合考虑处理效果与投药量,建议复合型微生物絮凝剂与聚合氯化铝铁的最佳复配比为2 mg/L:15 mg/L.     

铝硅合金中的六角形铁相

研究了亚共晶成分的铝硅合金Al-4%Si-2?-1%Mn中铁相形态与熔体处理的关系,发现六氯气烷精炼强烈促进初生α铁相的产生。在未经精炼处理时,合金微观组织中的铁相基本呈发达的树枝状,只有少量为初生汉字状铁相。用六氯乙烷精炼后,合金的组织中开始出现大量六角形的初生相。这种六角形铁相的形貌受冷却速度的影响较大。在精炼以后对合金长时间保温对该六角形铁相的出现和形态没有影响。由六氯乙烷精炼导致合金中大量六角形初生α铁相出现,可能是六氯乙烷精炼提高了α铁相的形核温度。     

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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