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731.
An. M. Kuznetsov A. N. Maslii L. I. Krishtalik 《Russian Journal of Electrochemistry》2009,45(1):87-92
Quantum-chemical calculations of solvation energy for ferrocene and cobaltocene molecules and their ionic forms in water, acetonitrile, methanol, acetone, and dimethylsulfoxide are performed in terms of the density functional method of the B3LYP type, taking into account the effect of solvent and using the Polarized Continuum Model (PCM). It is shown that the optimization of metallocene structure in liquid introduces only slight quantitative changes as compared with the data calculated for the structures optimized in the gas phase. It is shown that earlier observed deviation of experimental redox potentials of cobaltocene system in dimethylsulfoxide from the regularities of continuum electrostatics is caused by a stronger effect of this solvent on the distribution of electron density over the molecule of dissolved substance. 相似文献
732.
A novel chelated ferrocene‐based planar chiral N‐heterocyclic carbene‐Rh(I) complex was synthesized by a simple method. It was applied to the asymmetric transfer hydrogenation of prochiral ketones. Enantioselectivities of up to 67% ee were observed. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
733.
Abdullah Mohamed Asiri 《应用有机金属化学》2001,15(11):907-915
A novel series of organometallic donor–conjugated–acceptor dyes derived from ferrocene as the donor group have been synthesized via the Knoevenagel reaction of ferrocene carboxaldehyde and various active methylene compounds to give a range of dyes ranging from orange to blue–green in color. The most bathochromic dye is that derived from dialkyl thiobarbituric acid and the least is that derived from the tetralone. The dyes showed an unusual negative solvatochromism as the solvent polarity increased. All dyes synthesized are expected to have some non‐linear optical properties, as evidenced from the pronounced solvatochromism. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
734.
Multiwalled carbon nanotubes (MWCNTs) have been synthesized by the floating catalyst method using toluene as the carbon source and mixtures of ferrocene and ferrocenyl sulfide as the catalyst. Products were characterized by both low‐resolution and high‐resolution (HR) TEM analysis. It was found that the presence of large amounts of sulfur in the reactant mixture generated only amorphous carbon while lower amounts of sulfur led to mixtures of MWCNTs and carbon fibres. The product distribution, yield and the tube diameters varied with the sulfur content. HRTEM analysis revealed that the MWCNTs were poorly graphitized. Comparison with data using other sulfur sources (S8, thiophene) suggested that the proximity of the sulfur to the Fe catalyst in the gas phase did play a role in the CNT formation and provides a method of ‘carrying’ elements to a catalytic site. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
735.
Kowalska E. Byszewski P. Popławska M. Gładczuk L. Suwalski J. Diduszko R. Radomska J. 《Journal of Thermal Analysis and Calorimetry》2001,65(2):647-653
Journal of Thermal Analysis and Calorimetry - Properties of FeC60 solid samples were investigated by X-ray diffraction, 57Fe Mössbauer spectroscopy and magnetic measurements in order to... 相似文献
736.
Low‐temperature solution‐phase polycondensation of 1,1′‐ferrocenedicarboxylic acid chloride with newly synthesized aromatic diamines was carried out in tetrahydrofuran in the presence of triethylamine to form several new organometallic aromatic polyamides containing ferrocene units. The organometallic aromatic polyamides derived were in good yields ranging from 75 to 80%, amorphous with melting temperatures of > 350 °C. The monomers and the resulting polymers were characterized by their physical properties, elemental analysis, 1 H NMR and FTIR spectroscopy. The differential scanning calorimetry and thermogravimetric studies of the resulting aramids were also carried out. All the polymers were insoluble in common organic solvents. However, all dissolved in concentrated H2SO4 forming reddish brown solutions. Their glass transition temperatures were quite high, which is characteristic of aramids. They were also stable up to 450 °C with 10% mass losses (14–23%) recorded in the range 400–470 °C. The activation energies for decomposition of each aramid were also calculated using the Horowitz and Metzger method. All polymers showed reduced solution viscosities in concentrated sulphuric acid, which may be attributed to non‐Newtonian behavior. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
737.
二茂铁衍生物清除羟自由基的构效关系 总被引:1,自引:0,他引:1
采用化学发光法检测并比较了10种二茂铁衍生物清除羟自由基(·OH)活性,用循环伏安法研究了其电化学性质,进而探讨了取代基结构与清除·OH活性间的关系.结果表明,取代基共轭效应、诱导效应和体积都对衍生物清除·OH活性有明显影响.含共轭或吸电子取代基二茂铁衍生物,半波电位(E_(1/2))较高,清除·OH活性较弱;而含给电子取代基的二茂铁衍生物,E_(1/2)较低,清除·OH活性较强. 相似文献
738.
为了研究二茂铁类燃速催化剂对含镁铝富燃料推进剂一次燃烧性能的影响,设计了含不同种类、不同含量燃速催化剂的含镁铝富燃料推进剂配方,并对各配方的燃速、燃烧温度和爆热进行了测试。实验结果表明:叔丁基二茂铁、卡托辛和巴特辛均可明显提高含镁铝富燃料推进剂的燃速,其中巴特辛对含镁铝富燃料推进剂的燃速提升效果最为明显;加入叔丁基二茂铁和卡托辛后,含镁铝富燃料推进剂的燃速指数基本不变,但加入巴特辛后,推进剂的燃速与压强的关系背离指数关系;三种二茂铁类燃速催化剂均可通过提高一次燃烧过程中燃料和氧化剂的混合程度,使得推进剂的燃烧温度和放热量提高,其中巴特辛的效果最为明显。 相似文献
739.
Electrochemical detection of the specific gene carrying aberrant methylated cytosine was achieved by ferrocenyl naphthalene diimide carrying β‐cyclodextrin (β‐CD), FNC, coupled with the probe‐DNA‐immobilized electrode. The five CpG sites in a 24‐base sequence were selected as the target DNA on the CDH4 gene, which is associated with colorectal cancer. When methylated and unmethylated samples hybridized with the DNA probe (HS‐M24) immobilized on the electrode, an increased current signal was observed in the electrolyte containing FNC and correlated with the amount of target DNA. Furthermore, an increase in current (115 %) was observed when the PCR product of 105 bp was hybridized on the HS‐M24‐immobilized electrode, whereas a background level of current increase was observed in the case of unmethylated product. Such large discrimination ability might be due to the inter‐ and/or intra‐complex formation of ferrocene with β‐CD of FNC on the surface of the electrode. 相似文献
740.