首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 305 毫秒
1.
研究了赖氨酸1,4-丁二醇酯(Lys-4)对聚苯胺(PANI)氨气敏感膜的影响.通过静电纺丝技术得到含有Lys-4的混纺聚丙烯腈(PAN)纳米纤维膜,之后在静电纺纤维膜表面聚合苯胺得到具有核壳结构的纳米纤维复合膜.研究表明,Lys-4的加入提高了PANI敏感膜对氨气的灵敏度及对氨气的选择性,对于浓度为100μL/L的氨气,敏感膜的响应值从1.55增加到2.38,氨气最低检测浓度也进一步降低,为更加准确地检测氨气提供了新方法.  相似文献   

2.
本文以活性中间相炭微球为基底,过硫酸铵(APS)为氧化剂,通过原位化学聚合法聚合苯胺,得到聚苯胺/活性中间相炭微球复合材料(PANI/A-MCMB),采用扫描电子显微镜(SEM)、X-射线衍射仪(XRD)对其形貌和结构进行表征。以PANI/A-MCMB复合物为电极活性物质,1.0 mol/L H_2SO_4水溶液为电解液,组装对称型超级电容器,用循环伏安法(CV)、电化学交流阻抗(EIS)、恒流充放电(GCD)等测试手段测试超级电容器的电化学性能。实验结果表明,电流密度恒为0.1A/g时,PANI/A-MCMB复合材料单电极比容量为301.6F/g,1 000次循环后比容量为276.3F/g,比电容保持率为91.6%,较PANI材料(比容量为228F/g,1 000次循环后比电容保持率为39.5%)具有更好的比容量和循环稳定性。  相似文献   

3.
以盐酸为掺杂剂,在苯胺单体氧化合成导电聚苯胺的聚合反应过程中,通过加入N-苯基对苯二胺,可以显著加快聚苯胺的合成反应速度,并提高聚苯胺的产率.经电子显微镜观察发现,生成的聚苯胺呈现出明显的纳米纤维形貌特征,直径约50 nm,长度可达微米.实验表明:聚苯胺的产率和电导率都是随着HCl浓度的增加呈先增大后减小的趋势,浓度1 mol/L的盐酸掺杂下合成的聚苯胺的电导率最大;在苯胺和酸浓度固定时,改变氧化剂过硫酸铵的量也会影响聚苯胺纳米纤维的产率和电导率,n(苯胺)∶n(过硫酸铵)=1∶1时,生成物聚苯胺的电导率最大.  相似文献   

4.
采用界面聚合法制备了聚苯胺纳米纤维,详细研究了不同氧化剂/单体摩尔比和盐酸浓度对制得聚苯胺的形貌、分子结构和电导率的影响。结果表明:界面聚合过程中,较低的氧化剂/单体摩尔比(≤1:4)和较高的盐酸浓度(≥1mol/L)有利于生成结构规整和较高电导率的聚苯胺纤维;而在氧化剂用量较高和盐酸浓度较低时,聚苯胺纤维形成的同时,伴随着吩嗪类物质和苯胺齐聚物的生成,产物呈现聚集结构,其电导率也较低。  相似文献   

5.
以苯胺(PANI)和多壁碳管(MWNTs)为原料,采用原位聚合法合成聚苯胺,使聚苯胺均匀包覆在碳管表面,得到PANI/MWNTs复合材料.在1mol/L H2SO4电解液中,以甘汞电极为参比电极,通过循环伏安、恒流充放电测试其电化学特性.结果表明,当电流密度在1A/g时,复合材料的比电容达到241.6F/g,远大于纯碳...  相似文献   

6.
在阳离子表面活性剂十六烷基三甲基溴化铵(CTAB)和阴离子表面活性剂十二烷基硫酸钠(SDS)存在的条件下,以过硫酸铵(APS)为氧化剂,15℃下氧化聚合吡咯得到了具有高结晶度的规整片状结构聚吡咯。研究了体系中表面活性剂浓度对所得聚吡咯形貌的影响,发现当CTAB,SDS,Py单体浓度分别为0.01,0.01,0.03mol/L时所得片状结构产物较规整。初步探讨了具有高结晶度片状结构聚吡咯的形成机理:两种表面活性剂形成CTAB-SDS双胶束,Py单体以其为模板氧化聚合得到了片状结构的聚吡咯。  相似文献   

7.
在不同磁场强度下,用苯胺单体(An)和氧化剂过硫酸铵(APS),掺杂剂磺基水杨酸(SSA),乳化剂十二烷基苯磺酸钠(SDBS)合成了导电聚苯胺(PAn)。研究了氧化剂和掺杂剂用量对PAn掺杂率和电导率性能的影响;并采用红外光谱、X射线衍射、粒径分析、腐蚀电位曲线表征了PAn结构与性能的关系。结果表明:磁场对苯胺聚合的影响是正向的,磁场能减少掺杂剂的用量、提高产物的电导率;在乳化剂n(SDBS)/n(An)=0.45,氧化剂n(APS)/n(An)=0.8,掺杂剂SSA 0.3 mol.L^-1时,合成的PAn电导率最大;在磁场环境中合成的PAn导电性、粒径、防腐性、规整性等各方面与无磁场作用的产品相比均具有明显的优势。  相似文献   

8.
以三氟化锑和钼酸铵为锑源和钼源,采用水热法制备出锑钼锑(Sb2MoO6)和Sb2MoO6/纳米碳管(CNTs)复合物,利用苯胺聚合在Sb2MoO6和Sb2MoO6/CNTs上继续包覆聚苯胺(PANI)得到Sb2MoO6@PANI (Sb2MoO6/CNT)@PANI。采用XRD、SEM、EDX等手段对样品结构和形貌进行表征,结果发现制备的Sb2MoO6为不均匀的长为10μm的棒状形貌,而CNTs复合后的Sb2MoO6形貌变成厚约为100 nm的片状。作为锂离子电池负极材料,对所有合成的样品进行电化学性能测试,探讨CNTs复合和聚苯胺(PANI)包覆对Sb2MoO6样品的电化学性能的影响。结果表明:...  相似文献   

9.
以盐酸为掺杂剂,过硫酸铵(APS)为氧化剂,采用原位聚合的方法制备了导电聚酯片(PET)。为了增大导电高分子聚苯胺(PANI)在合成基材聚酯片表面的吸附量和黏附性,在苯胺聚合前对聚酯片进行酸处理。酸处理对聚酯片表面润湿性、化学组成及形貌的影响分别采用接触角测试仪、X射线光电子能谱仪、扫描电镜进行表征。苯胺聚合后聚酯片质量变化用于评估聚苯胺在聚酯片表面吸附量的大小。1-甲基-2-吡咯烷酮清洗后导电聚酯片颜色和电导率的变化用于判断聚苯胺在聚酯片表面的黏附性大小。实验结果表明,酸处理有效地提高了聚苯胺在聚酯片表面的吸附量和黏附性。该方法制备的导电聚酯片有望直接作为导电器件使用,可在一定程度上提高聚苯胺的可加工性。  相似文献   

10.
采用化学氧化聚合法,以氯仿为溶剂、无水氯化铁为氧化剂,制得了聚噻吩样品,使用傅里叶变换红外光谱仪、紫外可见漫反射光谱仪和高阻计对样品结构和电导率进行了分析测试,考察了噻吩浓度(0.05~0.20mol/L)、反应时间(1~12h)、反应温度(-32~0℃)、氧化剂与噻吩摩尔比(2~5)、后处理方式对聚噻吩样品电导率的影响。研究表明:上述条件均会影响聚噻吩的聚合程度和连接方式,进而影响其电导率。当噻吩浓度由0.05mol/L增至0.20mol/L时,样品电导率从10~(-13) S/m降至10~(-8) S/m;反应时间为3h所得样品的电导率最大,为10~(-10) S/m;当反应温度在0~-32℃时,其电导率均在10~(-13) S/m数量级;氧化剂与噻吩摩尔比n(FeCl_3)/n(Th)的增大会使其电导率增加(10~(-13)~10~(-10) S/m);反应结束后直接对反应物进行过滤洗涤得到的样品比室温挥发完溶剂再洗涤得到样品的电导率高五个数量级。综合聚噻吩的电导率和原料成本,选定噻吩浓度为0.10mol/L、反应时间为3h、反应温度为0℃、n(FeCl_3)/n(Th)=2,对反应物直接过滤洗涤为最佳制备条件,该条件下所得聚噻吩样品的电导率高达2.49×10~(-8) S/m。  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.
何延凌 《科技信息》2008,(4):258-258
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.  相似文献   

13.
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   

14.
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   

15.
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   

16.
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   

17.
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   

18.
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   

19.
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   

20.
<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   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号