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121.
Sabri Messaoudi Bechir Bejaoui Fourat Akrout Malika Bel Hassen Cherif Sammari 《International journal of quantum chemistry》2013,113(11):1633-1640
The heterogeneous uptake of N2O5 on mineral dust particles may play an important role in the removal of nitrogen oxides from the atmosphere. However, the reaction of N2O5 with the mineral particles is not well understood. The reaction of N2O5 with two Si(OH)4 monomers is explored using theoretical methods. This study represents a first step towards understanding the interaction of N2O5 with the hydroxyl groups of silica particles. Energies are calculated using MP2 single point calculations on the B3LYP optimized geometries and including B3LYP thermodynamic corrections. Four mechanisms are considered for the formation of two HNO3 and one H6Si2O7. The rate limiting activation barrier of the most favorable path is found to be 12.5 kcal mol?1. This reaction appears to be more favorable than the hydrolysis of N2O5 with one water molecule. These results are in agreement with experimental observations, which show that N2O5 reacts with OH groups of Saharan dust to form nitrate. © 2012 Wiley Periodicals, Inc. 相似文献
122.
Mehroz Iqbal Jameela Fatheema Qandeel Noor Malika Rani Muhammad Mumtaz Ren-Kui Zheng Saleem Ayaz Khan Syed Rizwan 《Materials Today Chemistry》2020
This study reports first synthesis of MXene-derived co-existing magnetic phases. New family of two-dimensional (2D) materials such as Ti3C2 namely MXene, having transition metal forming hexagonal structure with carbon atoms have attracted tremendous interest now a days. We have reported structural, optical and magnetic properties of un-doped and La-doped Ti3C2Tx MXene, synthesized using co-precipitation method. The lattice parameter (LP) calculated for La-MXene are a = 5.36 Å, c = 18.3 Å which are slightly different from the parent un-doped MXene (a = 5.35 Å, c = 19.2 Å), calculated from X-ray diffraction data. The doping of La+3 ions shrinks Ti3C2Tx layers perpendicular to the planes. The band gap for MXene is calculated to be 1.06 eV which is increased to 1.44 eV after doping of La+3 ion that shows its good semiconducting nature. The experimental results and density functional theory (DFT) calculations for magnetic properties of both the samples have been presented and discussed, indicating the co-existence of ferromagnetic-antiferromagnetic phases. The results presented here are novel and is first report on co-existence of magnetic properties of 2D carbides for potential applications in two-dimensional spintronics. 相似文献
123.
Iyad Karamé Dr. Malika Boualleg Jean‐Michel Camus Dr. Tarun K. Maishal Dr. Johan Alauzun Dr. Jean‐Marie Basset Dr. Christophe Copéret Dr. Robert J. P. Corriu Prof. Dr. Erwan Jeanneau Dr. Ahmad Mehdi Prof. Dr. Catherine Reyé Prof. Dr. Laurent Veyre Chloé Thieuleux Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(44):11820-11823
124.
Solubilities and liquid-liquid equilibrium (LLE) data for (water + ethanol + fluorobenzene) solutions are determined at T = (288.15, 298.15, 308.15) K and atmospheric pressure. The titration method is used to construct the binodal curves. All
measured solubilities and liquid-liquid equilibrium data are reproduced quantitatively by empirical equations and the NRTL
activity coefficient model. The correlated data are consistent to better than 0.3% in phase composition.
The studied temperatures have a small effect on the phase equilibrium properties of the investigated systems. The influence
of water concentration on the distribution coefficient of ethanol in the coexistent liquid phases and on the fluorobenzene
selectivity is important. Practically, fluorobenzene may well be used to produce absolute alcohol. 相似文献
125.
Djamila Oukacha-Hikem Malika Makhloufi-Chebli Anissa Amar Houria Bouherrou Yahia Rachedi Hacène Meghezzi 《合成通讯》2017,47(6):590-598
The synthesis of new 2-pyrone-based hydrazones has been prepared by the coupling of 6-methyl-2H-furo[3,2-c]pyran-3,4-dione with diazonium salts, obtained by diazotization of aniline derivatives. The structure of all compounds was established by spectroscopic methods, and the structure of the more stable conformer was theoretically confirmed by the potential energy profile analysis. The prepared 2-pyrone-based hydrazone dyes were acetylated and both groups of compounds showed moderate to good radical scavenging activity. 相似文献
126.
127.
A new synthetic pathway towards pentacyclic steroids was described via a ring-closing metathesis reaction as the key step. 相似文献
128.
Nawel Khettache Amel Bendjeddou Malika Berredjem Zine Regainia Veronique Montero Chantal Menut 《合成通讯》2013,43(16):2299-2305
An efficient three‐step synthesis of chiral 1,1′‐(sulfonyl)bisaziridines is described. Preparation of these compounds was carried out easily starting from N,N′‐sulfonyl bis‐(α‐L‐aminoester) to afford the title compounds in very good yields. These 1,1′‐(sulfonyl)bisaziridines can constitute interesting synthetic building blocks. 相似文献
129.
Carole Barbey Radia Bouasla Malika Berredjem Nathalie Dupont Pascal Retailleau Nour-Eddine Aouf Marc Lecouvey 《Tetrahedron》2012,68(44):9125-9130
The synthesis of new series of oxazolidinones having sulfonamide moieties is described. These compounds are synthesized in good yield starting prochiral 1,3-dichloro-2-propanol and chlorosulfonyl isocyanate. This strategy involves the formation of carboxylsulfamide by carbamoylation–sulfamoylation reaction followed by intermolecular cyclization. In order to determine the enantioselectivity during the cyclization step, X-ray studies of products are performed. 相似文献
130.