有机改性膨润土的制备及甲基橙废水脱色工艺研究

以十八烷基三甲基氯化铵（1831）为改性剂,制得有机阳离子改性膨润土．研究了有机膨润土投加量、吸附时间、废水pH值及废水初始浓度对甲基橙废水脱色率的影响．实验结果表明,有机阳离子改性膨润土投加量为1．5g／L,吸附时间为60min,废水pH值为8．0,废水初始浓度为100mg／L时,有机阳离子改性膨润土对甲基橙废水的脱色率达到98．08％．     

十八烷基三甲基氯化铵/双十八烷基二甲基氯化铵修饰ATP的制备及其吸附重金属的性能

使用12 mol/L的盐酸对天然凹凸棒石晶体（ATP）进行粗提处理，再用十八烷基三甲基氯化铵（DOTAC）和双十八烷基二甲基氯化铵（DODMAC）分别对ATP进行接枝改性，得到十八烷基三甲基氯化铵改性凹土（1831-ATP）和双十八烷基二甲基氯化铵改性凹土（D1821-ATP）。通过红外光谱（FT-IR）、X射线衍射（XRD）和比表面积（BET）等表征手段对改性前后凹土的晶体结构变化进行分析比较，并利用扫描电镜（SEM）观察了ATP、1831-ATP和D1821-ATP的形貌变化。对比研究了ATP、1831-ATP和D1821-ATP对常见重金属Pb²⁺的吸附性能，吸附实验结果表明：吸附平衡时间为4 h；在pH 9时，Pb²⁺在ATP、1831-ATP和D1821-ATP上的吸附量达到最高，去除率均达到99%以上，去除效果好。动力学和热力学模型拟合结果表明，吸附数据符合准二级动力学方程和Freundlich等温吸附方程。     

有机膨润土对吡虫啉的吸附

缓释剂的使用是提高农药效率和减少环境污染的有效策略。以四甲基氯化铵、十二烷基三甲基氯化铵和十六烷基三甲基氯化铵为改性剂制备系列有机膨润土,研究其对吡虫啉的等温吸附,分析吡虫啉在有机膨润土的吸附机理和影响因素。结果显示,与未改性膨润土相比,有机改性膨润土极大增强了膨润土对吡虫啉的吸附性能。吡虫啉分子具有较强的极性,无论是短碳链有机膨润土还是长碳链有机膨润土,暴露的硅氧烷表面相对于碳氢基团具有更强的吸附作用,延长季铵盐改性剂的碳链长度增强了有机膨润土对吡虫啉的吸附系数,但是降低了标碳化吸附系数。季铵盐载量对有机膨润土吸附性能的影响与其在膨润土的负载机理有关,载量小于1.0 CEC时,季铵盐主要以离子交换方式吸附到膨润土层间域,增加季铵盐用量可增强有机膨润土对吡虫啉的吸附能力。随着载量的进一步增加,超过可交换阳离子总量的季铵盐以分子形式进入膨润土层间域,降低了膨润土层间域的疏水性及其对吡虫啉的吸附能力。     

有机改性膨润土吸附模拟染料废水的工艺条件

为提高天然膨润土的吸附性能,以十六烷基三甲基氯化铵（CTAC）为改性剂,制备有机阳离子改性膨润土,并通过吸附实验分析有机改性剂用量、吸附时间、改性膨润土投加量、废水pH及初始质量浓度对模拟染料废水脱色率的影响。结果表明：有机改性剂质量分数为20%,有机改性膨润土投加量为1.0 g/L,振荡时间为30 min,废水pH为6.0,初始质量浓度为40 mg/L时,有机改性膨润土对模拟染料废水的处理效果最佳,脱色率可达到95.66%。该研究为新型改性膨润土处理染料废水提供了技术参考。     

膨润土有机改性及其对含油废水的吸附性能

以十八烷基三甲基溴化铵(OTAB)为改性剂,对天然膨润土进行有机改性,并采用X射线衍射仪对样品进行表征.考察温度、吸附时间、有机改性膨润土投加量、pH对含油废水中COD去除效果的影响.结果表明:OTAB成功插入到膨润土层间,其层间距增加.在30℃、有机改性膨润土投加量9g/L、吸附时间45 min、pH 6.0的条件下,有机改性膨润土对含油废水中COD的去除率可达86.8％.该研究为膨润土表面改性方法改进提供了借鉴.     

有机改性膨润土对氧化乐果的吸附作用

以钙基膨润土为原料,经提纯钠化后用十二烷基三甲基溴化铵进行有机改性.探讨了有机膨润土对有机磷农药氧化乐果的吸附性能,考察了pH、温度、吸附时间以及有机膨润土用量对吸附效果的影响.结果表明,改性膨润土对水中氧化乐果的去除能力优于原土,对50 mL浓度为0.8 g/L的氧化乐果溶液,在pH值为7.0、温度25℃、吸附时间30 min、有机膨润土投加量10 g/L条件下,对氧化乐果的去除率可达80.6%.     

有机膨润土的制备及其测试表征

为使膨润土能够在塑料中应用,需对膨润土有机化处理．以山东潍坊膨润土为原料,采用湿法提纯得到高纯度的膨润土,经无水碳酸钠钠化后选择不同的改性剂对其有机化处理,最终制备出有机膨润土,经测试分析表明：采用湿法提纯后,在65℃下加入质量分数为10％的Na2CO3恒温反应2h可得到钠基膨润土;在70℃条件下加入质量分数为20％的十八烷基苄基二甲基氯化铵和己内酰胺复合改性剂,调节pH为6后反应1．5h抽滤、干燥、粉碎后可得到改性效果优良的有机膨润土,其层间距可达到2．44nm．     

丙草胺在有机膨润土上的吸附和释放性能研究

为减少丙草胺的用量及其对环境的影响,以十二烷基三甲基氯化铵（ DTMAC）改性有机膨润土为载体制备丙草胺缓释剂,利用傅立叶红外光谱和X-射线衍射分析了有机膨润土的结构变化,并分析丙草胺在有机膨润土上的等温吸附对其释放动力学的影响。结果表明,DTMAC改性有机膨润土对丙草胺具有良好的吸附能力,并减低其在水中的释放速率。在丙草胺吸附和释放过程中疏水相互作用起关键作用,增加改性剂载量有助于增强膨润土的疏水性及其对丙草胺的吸附能力,从而获得更好的缓释效果。50％的丙草胺从DTMAC用量为可交换阳离子总量的60％、80％、100％和120％的有机膨润土的释放时间T50分别为2.05、2.07、2.97、4.26 d,其与丙草胺在相应有机膨润土上吸附的Freundlich系数Kf存在良好的线性函数关系。     

四川龙泉山地区膨润土改性研究

对四川龙泉山地区膨润土经过提纯、钠化处理,再用十六烷基三甲基澳化铵(CTMAB)进行了有机化改性试验研究.对改性土的X射线衍射分析、红外光谱分析及TG-DTA分析证明改性成功.得出有机化膨润土的最佳工艺条件为:当钠化膨润土矿浆的质量浓度为129.6g/L时,CTMAB加入量为钠化膨润土质量的45％,反应温度为65℃,反...     

膨润土多孔有机改性及其影响因素

以信阳膨润土为原料,将碳粉和淀粉按一定比例混入其中,挤压造粒,高温灼烧,再进行有机物覆盖,得多孔有机膨润土.讨论了有机覆盖剂的种类、覆盖体系的温度、pH值及碳粉的含量对PO43-吸附性能的影响.当用十六烷基三甲基氯化铵做覆盖剂,碳粉的含量为3.5%时,溶液体系的pH值为7-8,覆盖温度80℃时,吸附率达91.2%.     

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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