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1.
以钠基蒙脱土为原料,使用不同结构的季鏻盐对其进行有机改性,得到多种结构的季鏻盐改性蒙脱土并对苯酚吸附性能进行研究。探讨了改性蒙脱土层间距、吸附接触时间、改性蒙脱土浓度、温度、溶液p H对苯酚吸附性能的影响,结果表明:对200mg/L的苯酚溶液,改性剂为十六烷基三苯基溴化鏻,吸附接触时间为30min,改性蒙脱土用量为20g/L,温度为30℃,溶液p H为6,苯酚的去除率可达87.9%。  相似文献   

2.
将铜离子和十六烷基三甲基溴化铵阳离子依次与龙岩改性蒙脱土进行离子交换反应,制备了季铵盐-铜-蒙脱土复合材料。X-射线衍射(XRD)和红外光谱分析结果表明铜离子和季铵阳离子已插入到蒙脱土层间。抗菌试验结果表明,复合抗菌剂具有良好的抗菌性能,其对大肠杆菌(E.coli)和金黄色葡萄球菌(S.aureus)的最小抑菌浓度分别为250和125μg·mL-1。  相似文献   

3.
将锌离子和季铵阳离子依次与蒙脱土进行离子交换反应,制备了新型改性蒙脱土复合抗菌剂,并探讨了其最佳制备工艺条件.所制备的复合抗菌剂中锌离子和十四烷基二甲基苄基季铵阳离子的质量分数分别为2.95%和12.18%.XRD和TG分析结果表明,锌离子和季铵阳离子已交换到蒙脱土中,且复合抗菌剂中季铵阳离子的热分解起始温度约为210℃.文中还研究了复合抗菌剂的抗菌活性,发现其对大肠杆菌(E.coli)、金黄色葡萄球菌(S.aureus)和绿脓杆菌(P.cteyttginosct)等几种典型细菌的最小抑菌浓度(MIC)均小于或等于300mg/L,具有良好的抗菌性能和比较广的抗菌谱;复合抗菌剂在50℃的去离子水中浸泡30h后,仍然保持较好的抗菌活性,显示出优异的耐水性能.  相似文献   

4.
分别将钠基蒙脱土(Na-MMT)和有机改性蒙脱土(OMMT)引入到聚氧化乙烯-聚硅氧烷(PEO-PDMS)聚合物电解质体系中,通过溶液浇铸法制备得到新型蒙脱土复合聚合物电解质材料.适量加入蒙脱土,可有效降低聚合物体系的结晶度,提高聚合物电解质的电导率,室温下样品Na-MMT-6%电导率达到2.24×10-5 S/cm.同时,蒙脱土质量分数的增高还有利于聚合物电解质体系的热稳定性及力学性能的提高.此外,由于有机改性蒙脱土片层间距较钠基蒙脱土大,因此相同添加量下,二者对聚合物电解质的材料性能的影响存在差异.   相似文献   

5.
聚氯乙烯/蒙脱土纳米复合材料的结构与力学性能   总被引:5,自引:1,他引:5  
选用钠基蒙脱土和2种烷基季铵盐(十八烷基季铵盐和双十八烷基季铵盐)改性的蒙脱土,采用熔融共混的方法制备聚氯乙烯/蒙脱土纳米复合材料,并通过广角X射线衍射和透射电镜对复合材料的结构进行了表征.研究了蒙脱土种类和用量对复合材料力学性能的影响.结果表明,3种复合材料均具有插层型结构,钠基蒙脱土用量在ω=0.5%-7.0%,有机蒙脱土用量在20=0.5%-3.0%时,复合材料的综合力学性能均有明显提高;有机蒙脱土用量ω>5.0%以后,材料的力学性能降低,热稳定性变差.  相似文献   

6.
有机蒙脱土的制备及其结构表征   总被引:25,自引:0,他引:25  
为增加蒙脱土与有机相的相容性,制备有机蒙脱土,并观察蒙脱土的层状结构在有机化前后的变化.以钠基蒙脱土为原料,用季铵盐、有机胺和复合试剂作为有机插层剂与蒙脱土层间的Na+交换,制备出一系列有机蒙脱土,并对其结构进行表征.FTIR证明有机插层剂已进入蒙脱土的层间.XRD结果表明蒙脱土的层间距由1.2 nm增加到1.7~4.2 nm.TEM观察也表明蒙脱土的层间距增大,粒层厚度约为50 nm左右.研究结果表明选择高交换容量的钠基蒙脱土和合适的插层剂,制备的有机蒙脱土层间距增加明显.  相似文献   

7.
以钠基蒙脱土为基体、γ-氨丙基三乙氧基硅烷(KH-550)为改性剂,采用研钵研磨法、溶液搅拌法、微波加热法制备了有机改性蒙脱土,通过FT-IR、XRD、TG、SEM、UV-Vis等分析方法,对改性前后的蒙脱土样品进行了研究.结果表明:研钵研磨法能够实现对蒙脱土的氨基化合物的插层改性;相比于溶液搅拌法、微波加热法,研钵研磨法改性效果更好;经研钵研磨法改性后,钠基蒙脱土(001)面层间距由未改性时的1.07nm增加到2.42nm;研钵研磨法制备的有机蒙脱土上有机物负载率最高,700℃下失重率达16%;经研钵研磨法改性的蒙脱土在有机介质中的分散性和稳定性最好.  相似文献   

8.
采用壳聚糖-银络合物对钠基蒙脱土进行改性,合成壳聚糖-银/蒙脱土纳米中间体,研究了Ag-NO3浓度、振荡吸附时间对壳聚糖-银络合物合成的影响,用原子吸收分光光度计测Ag(I)含量可达25.8 mg/g.C ts,以及反应温度、反应配比、反应时间对蒙脱土插层效果的影响.用XRD、FTIR及TG-DTA对合成的壳聚糖-银/蒙脱土复合物进行了表征,结果表明C ts-Ag络合物已进入了蒙脱土层间,层间距高达5.732 nm,且C ts-Ag络合物热稳定温度为235℃.  相似文献   

9.
以钠基膨润土为原料,用十六烷基三甲基溴化铵(CTAB)进行有机改性,制得有机蒙脱土.研究了有机蒙脱土对有机氯农药百菌清废水的吸附性能,考察了溶液pH、温度、吸附时间以及有机蒙脱土用量对吸附率的影响.结果表明:百菌清溶液浓度为0.30 g/L、蒙脱土用量为10 g/L、pH为7、温度25℃、吸附时间为30min时,百菌清的脱除率可达82%.  相似文献   

10.
以钠基膨润土为原料,用十六烷基三甲基溴化铵(CTAB)进行有机改性,制得有机蒙脱土.研究了有机蒙脱土对有机氯农药百菌清废水的吸附性能,考察了溶液pH、温度、吸附时间以及有机蒙脱土用量对吸附率的影响.结果表明:百菌清溶液浓度为0.30 g/L、蒙脱土用量为10 g/L、pH为7、温度25℃、吸附时间为30min时,百菌清的脱除率可达82%.  相似文献   

11.
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.  相似文献   

12.
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。  相似文献   

13.
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.  相似文献   

14.
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-  相似文献   

15.
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-  相似文献   

16.
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  相似文献   

17.
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  相似文献   

18.
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  相似文献   

19.
<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  相似文献   

20.
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