986 resultados para 1995_01261852 CTD-60 4302601


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C-60 films, prepared by solution casting, were studied by means of in situ probe beam deflection (PBD) combined with cyclic voltammetry (CV). PBD is a powerful technique for investigation of phenomena at the electrode/electrolyte interface in acetonitrile with quaternary ammonium and alkali metal salts as supporting electrolytes. In tetra-n-butylammonium (TBA(+)) salt solution, a stable CV can be obtained during the first two reduction/reoxidation waves. On reduction, injection of cations to maintain charge balance and dissolution of small amount of C-60(-) (TEA(+)) and/or C-60(2-) (TBA(+))(2) are detected. During the reoxidation process ejection of cations and injection of anions occur simultaneously, especially for the second reoxidation wave. In the case where TBABr is the supporting electrolyte, the accompanied behavior is more complicated than in TBABF(4), TBAClO(4), and TBAPF(6) solutions. A small pair of prewaves in CV are proposed due to oxidation/reduction of C-60 domains but not dissolution/redeposition of C-60 film. Extending the potential scan range to the third reduction wave, no apparent corresponding reoxidation wave is related to the third reduction wave, the electroactivity of the film disappears rapidly and dissolution of C-60 film is observed. In tetraethylammonium (TEA(+)) and NAClO(4) solutions, the electrochemistry of the C-60 films is unstable, and potential scans lead to dissolution of flaking of the film.

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A new method for the preparation of polyalkyl and polyarenefullerene derivatives C-60(RH)(n)(R=Bu,n=1-3; R=Ph,n=1-10) by the reaction of C-60 with organotin hydride in toluene is described. Another series of products of stannanes R(a)Sn(b)H(c) (R=Bu, a=3-8, b=1-4, c=0-3 R=Ph, a=3-11, b=1-5, c=0-4) were also obtained, which shows that C-60 can catalyze polymerization of organic-tin. These products were determined by mass and infrared spectrometry. And the possible reaction mechanisms are discussed.

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The reaction of buckministerfullerene (C-60) with tri-n-blltyltin hydride(n-Bu(3)SnH) in toluene solution has been investigated. According to mass spectrometry analysis, the products of above reaction are C-60(BuH)(n)(n = 1 similar to 3) and Bu(x)Sn(y)H(x) (x = 3 similar to 8, y = 1 similar to 4,approximate to = 0 similar to 3). The reaction maybe provide a new method for the synthesis of alkylated fullerene derivatives. Where C-60 also takes a role of a catalysis of organtic-tin polymerization. The radical reaction mechanism has been discussed.

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In this paper, we introduce a very convenient method to produce water soluble C-60 derivatives- fullerols by the reaction of C-60 with potassium in toluene solution, FT-IR, H-1 NMR and FABMS proved the multi-hydroxyl and C-60 cage structures of the products, The properties of unstability to light, heat, basicity of aqueous solution and the solubility in some common polar solvents were also described.

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C_(60)(OH)_x的简便合成及性质孙大勇,刘子阳,郭兴华,佘益民,周雨,刘淑莹(中国科学院长春应用化学研究所应用谱学开放实验室,长春,130022)关键词C_(60),水溶性富勒醇,钾,不稳定性,溶解度水溶性C60化合物的合成及性质研究作为C60?..

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C_(60)与n-Bu_3SnH的自由基反应研究余益民,郭兴华,刘子阳,刘淑莹,傅芳信,钱明星(中国科学院长春应用化学研究所,长春,130022)(东北师范大学化学系)关键词自由基反应,富勒烯,三丁基锡氢化物,自由基海绵自Kratschmer等[1]实...

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本文简要回顾C(60)发展十年来在功能材科研究领域取得的进展,对一些具有潜在应用前景的研究方向加以简要介绍。

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C_(60)的聚合反应是一项十分有意义的研究课题。“珍珠项链”式的C_(60)聚合物将具有优良的导电和非线性光学性能,有可能成为新型功能高分子材料。自Yeretzian等人于1992年采用激光蒸发C_(60)膜率先在气相中实现C_(60)聚合以来,这一领域的研究一直方兴未艾。但总体来看,采用激光等手段尚不能得到宏观量的结构规整的聚合物。1994年瑞士科学家Pekker等人采用金属钾与C_(60)高温蒸气的反应,在特定的温区得到聚合度逾100000的C_(60)线性聚合物,表明钾对于

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研究了交联XE-60和PEG-20M极性固定相非晶硅膜改性弹性玻璃毛细管柱,在适当的温度下,用过氧化二异丙苯(DCUP)游离基引发交联,成功地制备了XE-60和PEG-20M极性柱,它们均具有柱效高、惰性好、化学稳定性好和耐溶剂、抗腐蚀、耐高温等性能,是一种新型的极性交联柱。

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综述近年在水溶性C_(60)衍生物合成及生物活性方面所取得的进展。

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The DCI MS of C-60 with the reactions of gaseous cyclohexane and cyclohexene have been studied. Several kinds reactions of C-60 have been observed. The results show that the gasphase C-60 has very active chemical properties. The adduct ions of [C60C4H7](+) and [C60C5H7](+) may be formed by [2+4] cycloaddition where one of double bonds of C-60 acted as a dienophilic unit.

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Gas phase ion-molecular reactions of C-60 with the ion system of CS2 have been studied in the ion source of mass spectrometer. It was found for the first time that the sulfuric derivative of C-60-C60S+ was the main ions in the ion source, they did not react with C-60 to form adduct ions due to their highly saturated structures. According to the dynamic analysis, the product ion came from the reaction of C-60 with the fragment ion S+. The adduct ion may have the structure of epsulfide that is advantageous in energy.

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In chemical ionization mass spectrometry (CIMS) gas phase C-60(+) or C-60 can react with fragment ions from three chloromethane and four multichloroethane molecular ions via ion-molecule reactions. A dozen of gas-phase adduct ions of C-60 are observed, and most of them contain chlorine atoms. The results of the comparison and analysis show that the relative intensities of adductions are not directly proportional to the corresponding fragment ions in the MS of reagents,which implies that some fragment ions containing radicals are more reactive with C-60(+) or C-60. This indicates that the alkene-like C-60(+) or C-60 can act as a radical sponge in addition reactions.

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Gas phase reactions of C-60 and C-70 with the ion system of acetone under chemical ionization conditions have been studied. C-60 and C-70 can react with acetyl and oxonium ions, which come from self-chemical ionization of acetone, to form adduct ions. In addition, C-60 and C-70 can accept protons to produce protonated ions. C-70 is more active in the above reactions than C-60 because of its stronger gas-phase basicity. A sigma-bond between C-60 and an acyl carbon atom can be formed to produce stable acetylated C-60 ions. The above results may be relevant to the acetylation reactions of C-60 in the condensed phase.

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Gas-phase ion-molecular reactions of C-60 and C-70 with the ion system of acetone have been studied in this paper. The ions of protoned and acetylized C-60 and C-70 were formed by the reactions of C-60 and C-70 with some ions which existed in the ion system when mass spectrometer worked on chemical ionization conditions. The reactivity of C-70 is greater than that of C-60. Results of quantum chemical calculation for the adduct ions showed a sigma bond between the acyl carbon atom and C-60 may be Formed. These results will provide some valuable informations on the condense-phase acetylization of C-60.