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81.
Polyfunctional activity of metal complexes containing 2,6-Di-tert-butylphenol in catalytic oxidation
Elena R. Milaeva Dmitry B. Shpakovsky Valery S. Petrosyan 《Macromolecular Symposia》2003,204(1):191-204
The results of the investigations of metal complexes containing 2,6-di-tert-butilphenol in the ligand environment in catalytic homogeneous oxidation of organic compounds are reviewed. The liquid-phase oxidation of hydrocarbons, olefins, aminophenol and unsaturated fatty acids by molecular oxygen in the presence of phthalocyanines, porphyrins, σ-aryl and π-allyl transition metal complexes is described. The change of the reactivity of organometallic and coordination compounds by oxidation of the redox active phenolic group opens up the possibility to use them as polyfunctional catalytic systems showing positive and/or negative catalytic effects. 相似文献
82.
83.
Kozhevnikova EF Derouane EG Kozhevnikov IV 《Chemical communications (Cambridge, England)》2002,(11):1178-1179
Heteropoly acid H3PW12O40 is a very efficient and environmentally benign catalyst for the Fries rearrangement of phenyl acetate in homogeneous or heterogeneous liquid-phase systems at 100-150 degrees C. 相似文献
84.
Elena Molteni Giovanni Onida Giancarlo Cappellini 《The European Physical Journal B - Condensed Matter and Complex Systems》2016,89(4):98
We study the electronic properties of the Si(001):Uracil, Si(001):Thymine, andSi(001):5-Fluorouracil systems, focusing on the Si dimer-bridging configuration withadsorption governed by carbonyl groups. While the overall structural and electronicproperties are similar, with small differences due to chemical substitutions, much largereffects on the surface band dispersion and bandgap show up as a function of the molecularorientation with respect to the surface. An off-normal orientation of the molecular planesis favored, showing larger bandgap and lower total energy than the upright position. Wealso analyze the localization of gap-edge occupied and unoccupied surface states. 相似文献
85.
86.
Vapor pressure osmometry was applied to the systems calcium l-aspartate ((S)-aminobutanedioic acid calcium salt)?+?water for varying molalities of Ca–l-Asp (mCa–l-Asp?=?0.01–1.02 mol·kg?1) and guanidinium hydrochloride (methanamidine hydrochloride)?+?sodium L–aspartate ((S)–aminobutanedioic acid sodium salt)?+?water, varying the molalities of GndmCl and Na–l-Asp (mNa–l-Asp?=?0.1, 0.25, 0.4, 0.57 mol·kg?1 and mGndmCl?=?0.1–1.1 mol·kg?1) at T?=?298.15 K and 310.15 K. From vapor pressure osmometry, activities of water, and the corresponding osmotic coefficients of the mixtures Ca–l-Asp?+?water and Na–l-Asp?+?GndmCl?+?water have been calculated, both being directly related to the chemical potentials of the different species and therefore to their Gibbs energy. Mean molal ion activity coefficients were obtained from experimental data fits with the Pitzer equations and the corresponding dual and triple interaction parameters were derived for the Ca–l-Asp?+?water binary system. β(2) Pitzer parameters different from zero are required for Ca–l-Asp in water to reproduce the osmotic coefficient decrease with increasing concentration. Mean Spherical Approximation parameters accounting for Coulomb and short range interactions that describe the calcium and magnesium aspartates and glutamates are given. The decrease in the chemical potential of the aspartates corresponds to the Hofmeister series: NaAsp?>?Mg(Asp)2?>?CaAsp. A strong interaction between amino acid and salt due to specific dispersion interactions in amino acid salt systems containing guanidinium based salt has been revealed that is in agreement with MD and half-empirical quantum-chemical calculations. 相似文献
87.
High‐Pressure Synthesis of a Nitrogen‐Rich Inclusion Compound ReN8⋅x N2 with Conjugated Polymeric Nitrogen Chains 下载免费PDF全文
Dr. Maxim Bykov Dr. Elena Bykova Egor Koemets Timofey Fedotenko Georgios Aprilis Dr. Konstantin Glazyrin Dr. Hanns‐Peter Liermann Dr. Alena V. Ponomareva Johan Tidholm Dr. Ferenc Tasnádi Prof. Dr. Igor A. Abrikosov Prof. Dr. Natalia Dubrovinskaia Prof. Dr. Leonid Dubrovinsky 《Angewandte Chemie (International ed. in English)》2018,57(29):9048-9053
A nitrogen‐rich compound, ReN8?x N2, was synthesized by a direct reaction between rhenium and nitrogen at high pressure and high temperature in a laser‐heated diamond anvil cell. Single‐crystal X‐ray diffraction revealed that the crystal structure, which is based on the ReN8 framework, has rectangular‐shaped channels that accommodate nitrogen molecules. Thus, despite a very high synthesis pressure, exceeding 100 GPa, ReN8?x N2 is an inclusion compound. The amount of trapped nitrogen (x) depends on the synthesis conditions. The polydiazenediyl chains [?N=N?]∞ that constitute the framework have not been previously observed in any compound. Ab initio calculations on ReN8?x N2 provide strong support for the experimental results and conclusions. 相似文献
88.
Kosyakov Dmitry S. Anikeenko Elena A. Ul’yanovskii Nikolay V. Khoroshev Oleg Yu Shavrina Irina S. Gorbova Natalya S. 《Analytical and bioanalytical chemistry》2018,410(28):7429-7439
Analytical and Bioanalytical Chemistry - The use of matrix-assisted laser desorption/ionization (MALDI) mass spectrometry for the study of lignin is still extremely limited due to its low... 相似文献
89.
Brandaleze Elena Bazán Vanesa Orozco Ivana Valentini Marcelo Gomez Giuliana 《Journal of Thermal Analysis and Calorimetry》2018,133(1):435-441
Journal of Thermal Analysis and Calorimetry - Rhenium production from copper and molybdenum sulphides involves the use of a pyrometallurgical process. In traditional pyrometallurgy processes, gases... 相似文献
90.
Lysenko Elena N. Surzhikov Anatoly P. Nikolaev Evgeniy V. Vlasov Vitaly A. Zhuravkov Sergey P. 《Journal of Thermal Analysis and Calorimetry》2018,134(1):307-312
Journal of Thermal Analysis and Calorimetry - The effect of mechanical milling on the oxidation kinetics of ultrafine iron powders was investigated by thermogravimetric (TG) analysis. The initial... 相似文献