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961.
962.
Intermolecular H···O═C bonds induced 2D self‐assembly of thiophene based diketopyrrolopyrrole derivative 下载免费PDF全文
Yican Wu Jinxing Li Bao Zha Xinrui Miao Lei Ying Wenli Deng 《Surface and interface analysis : SIA》2017,49(8):735-739
Compounds with diketopyrrolopyrrole (DPP) and thiophene moieties have attracted considerable attention because of their promising charge transport properties. The molecular conformation and self‐assembly of 2,5‐dihexadecyl‐3,6‐di(thiophen‐2‐yl)‐2,5‐dihydropyrrolo[3,4‐c]pyrrole‐1,4‐dione (TDPP‐C16) molecule have been investigated by scanning tunneling microscopy and density functional theory alculation. The TDPP‐C16 molecules adsorb with their optimized S‐shaped conformation and form a zipper‐like pattern on highly oriented pyrolytic graphite surface. R and S rotated structures are observed. The nanostructure is dominated by intermolecular double hydrogen bonds between C═O of the DPP units and hydrogen atom of thiophene rings in the neighboring molecules in each row. Atomic force microscopy and density functional theory calculation also display the existence of strong intermolecular hydrogen bonding. The results provide molecular evidence for the intermolecular interactions of the surface structure, which could benefit to the design of the organic semiconducting materials and understanding of underlying principle of charge transfer process. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
963.
Effect of cold plasma process on the surface wettability of NBR and the kerosene resistance of NBR/PTFE composites 下载免费PDF全文
In this study, first the acrylonitrile‐butadiene rubber (NBR5080) was modified by argon (Ar), air, and oxygen plasma at low temperature, and the effect of plasma process (power, time, and pressure) on the surface properties of NBR5080, the interfacial properties, physical properties, and the mechanical properties of NBR5080/polytetrafluoroethylene (PTFE) composites were investigated. The state contact angle and the surface free energy were applied to characterize the surface wettability of NBR5080. The scanning electron microscope and the atomic force microscope were used to observe the surface morphology of the NBR5080. The chemical changes on the NBR5080 surface were verified by X‐ray photoelectron spectroscopy. The average water contact angle the NBR5080 declined obviously when NBR5080 was treated by Ar (100 W/600 s/30 Pa). The active oxygen groups were introduced onto the surface of NBR5080 by cold plasma treatment and more active group containing oxygen were observed on the samples treated by Ar plasma. The peel strength between the NBR5080 and the PTFE was increased obviously, which increased from 0 to 44.2 N?m?1 for Ar plasma treatment. The mass and the dimension of NBR5080 increase sharply after immersing in kerosene, whereas the NBR5080/PTFE composites changed a little. The mechanical properties of NBR5080 and NBR5080/PTFE composites decreased as the immersion time in kerosene increased, but the decreased degree of NBR5080 is higher than NBR5080/PTFE composites. 相似文献
964.
965.
Convenient selective methods of synthesis of the title compounds, based on oxidation of di(propen-1-yl)sulfide with 30% H2O2, have been developed.Institute of Organic Chemistry, Siberian Branch, Russian Academy of Sciences, 664033 Irkutsk. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 3, pp. 675–679, March, 1992. 相似文献
966.
J. Bujdák H. Slosiariková B. Číčel 《Journal of inclusion phenomena and macrocyclic chemistry》1992,13(4):321-327
Reduced charge montmorillonites (RCM) were prepared using lithium thermal treatment. The sorption of octylammonium (OA), dodecylammonium (DDA) and hexadecylammonium ions (HDA) on differently charged samples were studied. The amounts of DDA and HDA sorbed on each RCM exceed the cation exchange capacity (CEC) but that of OA exceeds only the CEC of samples with the lowest CEC. The sorption is affected not only by the layer charge but also by the formation of collapsed interlayer spaces in the lowest charged montmorillonites. X-ray measurements confirmed the decrease of the layer charge after lithium thermal treatment and the layer charge heterogeneity in RCMs. 相似文献
967.
S. V. Koroteev D. S. Ermekov Z. V. Todres A. D. Malievskii 《Russian Chemical Bulletin》1992,41(1):60-64
Reaction of cis-,-dinitrostilbene (substrate) with morpholine (reagent) in n-hexane leads to cis--nitro--morpholinostilbene (end product). The process is of first order with respect to the substrate and second order with respect to the reagent. Possible reaction mechanisms are analyzed, and it is established that the following are most probable on the basis of kinetic patterns and stereochemistry: development of a charge transfer complex having a hydrogen bond between the substrate nitro group and reagent amino group; reaction of the complex with a second reagent molecule and formation of a carbanion (this stage determines the overall reaction rate); and detachment of a nitrite ion from the nitrocarbanion and its protonation to form the end product.N. N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, 117977 Moscow. A. N. Nesmeyanov Institute of Heteroorganic Compound, Russian Academy of Sciences, 117813 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 1, pp. 78–83, January, 1992. 相似文献
968.
硫酸氢铵分解动力学及其分解机理的研究 总被引:1,自引:0,他引:1
为了筛选适合的化学贮能系统,Wentworth等人曾提出了十项筛选标准。照此标准衡量,硫酸氢铵的分解-合成反应是一个十分理想的贮能系统: NH_4HSO_4(l)?NH_3(g)+H_2(g)+SO_3(g)Prengle也曾就此反应应用于太阳能电站贮能系统的可行性作过理论上的探讨.但是,有关该反应的基础研究进行的还很不够,特别有关分解动力学和分解机理的研究文献尚未见报导。本文用等温热重法和程序升温热重法对硫酸氢铵的热分解动力学进行了研究,并确定了分解机理,为贮能系统的实际应用提供了基础数据。 相似文献
969.
电化学法测定几种稀土贮氢合金的热力学函数 总被引:14,自引:0,他引:14
贮氢材料由于能可逆地吸放氢,得到了广泛地应用.特别是以贮氢材料为负极制成的氢镍二次电池,容量为同类型镉镍电池的1.5~2倍,且电压又相近,是镉镍电池的理想换代产品,受到人们普遍的关注。LaNi_(4.5)Mn_(0.5),LaNi_(4.9)Sn_(0.1)和La_(0.8)Nd_(0.2)Ni_(2.5)Co_(2.4)Al_(0.1)是电化学性能较优越的贮氢合金。LaNi_(4.5)Mn_(0.5)的电化学容量高,理论容量可达400mAh.g~(-1).LaNi_(4.9)Sn_(0.1)和La_(0.8) Nd_(0.2) 相似文献
970.
碲氢化钠是一个用途广泛的磁试剂,自作为有用的去溴试剂以来,日益受到化学工作者的关注,不断有文献报道它的合成及应用.例如能有效地还原卤代烃、硝基化合物、叠氮化合物和亚胺等.近年来,Katritzky报道了胺烷基化苯并三氮唑衍生物的合成及应用,此衍生物中的苯并三氮唑基是很好的离去基团,易被各种亲核试剂所取代.我们在前文中对硒氢化钠与胺烷基化苯并三氮唑反应生成二苄基二硒醚的合成进行了报道.本文用碲氢化钠与胺烷基化苯并三氮唑反应,结果生成还原产物N-取代胺. 相似文献