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1.
反应条件对聚苯胺—邻甲氧基苯胺性能的影响   总被引:2,自引:2,他引:2  
邻甲氧基苯胺与苯胺共聚能有效提高聚苯 溶解性和可加工性,所得的聚苯胺-邻甲氧基苯胺具有很好的电致变色性,通过考查单体摩尔配比、单体浓度、氧化剂用量、反应时间、反应温度、酸度对聚苯胺-邻甲氧基苯胺性能的影响,得到了在苯胺与邻甲氧基苯胺摩尔配比为3:1时,制得溶解性和电致变色性都很好且产率较高的聚苯胺-邻甲氧基苯胺的较佳合成反应条件,用红外光谱表征了各聚合物的结构。  相似文献   

2.
以苯胺为单体,过硫酸铵为氧化剂,通过化学氧化法合成聚苯胺,并以其为导电填料,以环氧树脂为成膜物,制备出一种电导率在0.04-0.05 S/cm范围内的新型导电防腐涂料。讨论了氧化剂的用量、盐酸的浓度、反应时间和反应温度等对聚苯胺涂料导电性的影响以及在盐雾、酸性、碱性和油水条件下,其腐蚀情况和电导率的变化。结果表明:实验最佳制备条件为:氧化剂与苯胺的摩尔比1∶1,反应温度小于5℃,反应时间4 h,盐酸浓度为2 mol/L,聚苯胺的质量分数为15%~20%;除碱性条件外,导电聚苯胺防腐涂料在油水、盐雾和酸性条件下均具有良好的导电性和防腐蚀性能。  相似文献   

3.
聚苯胺的化学合成、结构及导电性能   总被引:2,自引:0,他引:2  
导电聚苯胺是结构和性能最稳定的导电高分子材料,有较广泛的应用前景。本实验用化学氧化合成方法,较系统地研究了氧化剂种类、用量、介质酸的浓度以及聚合反应温度等因素对苯胺聚合反应及产物性能的影响;找出了最适宜的合成反应条件和特殊的后处理工艺,并合成出了电导率高达30.65S/cm,收率达127.8%的高性能导电聚苯胺  相似文献   

4.
研究了以二氧化锰为氧化荆,苯胺(An)化学氧化聚合的新型反应.探讨了氧化荆的用量、反应体系酸度、反应温度等条件对聚苯胺(PAn)的产率和电导率的影响.在2.7mol/L的盐酸介质中二氧化锰与苯胺摩尔比为0.7的条件下室温氧化聚合4h,可得到电导率为12.5S/cm的聚苯胺,产率为73%.对产物聚苯胺的结构用红外光谱进行了表征.  相似文献   

5.
双酚B的催化合成研究   总被引:2,自引:0,他引:2  
选用浓盐酸作催化剂合成了双酚B.双酚B的收率可达78.5%.并对影响合成过程的主要因素进行了研究.结果表明:主催化剂的类型及用量、助催化剂的用量、酚酮摩尔比、反应温度、反应时间等为主要影响因素.制备双酚B的最佳工艺条件为:主催化剂选用浓盐酸,其用量为33.3mL;助催化剂选用巯基乙酸,其用量为0.15mL;酚酮摩尔比为2.5∶1.0;反应温度为60~65℃;反应时间6h.  相似文献   

6.
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   

7.
掺杂聚苯胺复合材料电磁参数及吸波性能研究   总被引:5,自引:0,他引:5  
采用3cm波导式测量线在8~14GHz频率范围内,用多点拟合的实验和计算方法对掺杂聚苯胺的微波吸收特性及参量进行了研究.发现浓H2SO4掺杂本征态聚苯胺(PAn)所合成材料的电损耗很小、磁损耗较大(相对于HCI—PAn).FeCl2掺杂浓H2SO4-PAn材料可合成磁损耗较高、基本上有利于吸收微波的材料;更令人注意的是,将HCl—PAn与浓H2SO4-PAn—FeCl3按一定的比例混合,可以合成出平均衰减为13.37dB、最大衰减为26.7dB、密度为0.7g/cm^3、频宽为10.34~14GHz的很有利于吸收微波的材料.同时.比较了有机酸掺杂聚苯胺DBSA—PAn与HCI—PAn的吸波性能。  相似文献   

8.
温度对化学氧化法合成盐酸掺杂聚苯胺的影响   总被引:2,自引:0,他引:2  
研究了温度对化学氧化法合成HCl掺杂聚苯胺(PANI-HCl)结构与性能的影响,利用四探针电导率测量法、FTIR、Uv-Vis、 XRD等对产物进行表征.结果表明,反应温度升高,聚苯胺的结晶度随合成温度升高而提高,结晶性能变好,当反应温度40℃时,2θ=21.04°处出现明显衍射峰.PANI-HCl的电导率在半导体范围,20℃时具有较高的电导率0.54 S/cm.  相似文献   

9.
乳化剂复配制备羟基有机硅柔软剂   总被引:1,自引:0,他引:1  
羟基硅油乳液是一种无毒无污染的绿色产品,通过本体聚合,研究了阴离子/非离子乳化剂进行复配和羟基硅油乳液的合成。结果表明:SDBS/OP-10体系在表面张力和润湿力方面,都优于SDBS/TX-7和SDBS/TX-8体系;合成最佳工艺条件为SDBS与OP-10最佳比例为1~1.5时,表面活性剂用量为D4单体质量分数的1.5%左右,有机酸催化剂(DBSA)用量为D4单体质量分数的6%左右,反应温度在70℃左右,聚合反应时间3~5 h。  相似文献   

10.
以过氧化钨酸(TAP)为均相催化剂及过氧化氢(H2O2)为氧化剂,在十二烷基苯磺酸(DBSA)的存在下直接合成掺杂态导电性聚苯胺微粒子.研究了TAP-H2O2及DBSA的用量、反应温度和时间对聚苯胺的导电率及产率的影响.调查了生成的聚苯胺微粒子在有机溶剂中的溶解性能.通过红外、紫外及核磁共振对掺杂态聚苯胺微粒子的结构进行了鉴定.粒径分布在1.10-13.50μm范围内.  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.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

13.
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   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
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   

16.
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   

17.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

18.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

19.
20.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

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