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101.
A. K. Osipov A. A. Anis’kov A. Yu. Yegorova 《Russian Journal of Organic Chemistry》2017,53(2):210-214
Convenient method of one-pot tricomponent synthesis of (arylamino)methylidene-3?-furan-2-ones was developed. Basing on combined spectral data and NOE-experiments the features of stereostructures of obtained arylaminomethylidenederivatives were revealed. 相似文献
102.
Lan Wu James A. Sawada Daniel B. Kuznicki Tetyana Kuznicki Steven M. Kuznicki 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(1):527-532
I-129 is a hazardous fission product due to its long half life and ability to bioaccumulate. Silver mordenite has been studied for the removal of I-129 because of its hydrothermal stability arising from a high Si/Al ratio which subsequently limits its silver loading and iodine capacity. Titanosilicate ETS-10 and the sodium nanotitanate ETS-2 were exchanged to over 35 wt % silver and exposed to saturated iodine vapour at 80 °C under dry and humid conditions. The results indicate that the silver on these materials is reactive toward iodine and that the majority of the silver ions are utilized. 相似文献
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104.
V. V. Alekseyev I. V. Lagoda S. I. Yakimovich M. B. Yegorova 《Chemistry of Heterocyclic Compounds》2010,46(8):971-982
The reaction of a series of 1,2-dicarbonyl compounds with thiocarbohydrazide and its 1- and 1,4-alkyl-(aryl)-substituted analogs
has been studied. Treatment of diacetyl with the polynucleophiles indicated gives monohydrazones and/or 5-methylene-4,5-dihydro-2H-[1,2,4]triazine-3-thiones.
Reaction of phenylglyoxal and benzil with thiocarbohydrazide yields 5-hydroxy- or 5-alkoxy-4,5-dihydro-2H-[1,2,4]triazine-3-thiones
depending on the nature of the solvent. The products of condensation with 1,1-dimethylthiocarbohydrazide showed a thiocarbonohydrazone
– 5-hydroxy-4,5-dihydro-2H-[1,2,4]tri-azine-3-thione ring-chain type equilibrium. 相似文献
105.
106.
We present a "basin-sampling" approach for calculation of the potential energy density of states for classical statistical models. It combines a Wang-Landau-type uniform sampling of local minima and a novel approach for approximating the relative contributions from local minima in terms of the volumes of basins of attraction. We have employed basin-sampling to study phase changes in atomic clusters modeled by the Lennard-Jones potential and for ionic clusters. The approach proves to be efficient for systems involving broken ergodicity and has allowed us to calculate converged heat capacity curves for systems that could previously only be treated using the harmonic superposition approximation. Benchmarks are also provided by comparison with parallel tempering and Wang-Landau simulations, where these proved feasible. 相似文献
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108.
Brian F. G. Johnson Tetyana Khimyak Florian W. Wansel Gillian Phillips Sophie Hermans 《Journal of Cluster Science》2004,15(3):315-329
The reactions of [Ru
m
C(CO)
n
] (m = 5, n = 15; 3
m = 6, n = 17; 4) with PCy2(CH2)3Ph afforded mono- and bis-substituted derivatives [Ru5C(CO)14PCy2 (CH2)3Ph] 13, [Ru5C(CO)13{PCy2(CH2)3Ph}2] 14, [Ru6C(CO)16PCy2(CH2)3Ph] 15 and [Ru6C(CO)15{PCy2(CH2)3Ph}2] 16. Compounds 13–16 were characterised spectroscopically and the molecular and crystal structures of compound 13, 13a ([Ru5C(CO)14PPh2(CH2)3Ph]), 14 and 16 were determined by single crystal X-ray crystallography. Compound [Ru6C(CO)15{PCy2(CH2)3Ph}2] 16 was subjected to a thermal treatment in dibutylether, however no reaction was observed. 相似文献
109.
Butcher CP Dyson PJ Johnson BF Khimyak T McIndoe JS 《Chemistry (Weinheim an der Bergstrasse, Germany)》2003,9(4):944-950
The anionic clusters [HOs(5)(CO)(15)](-), [PtRu(5)C(CO)(15)](2-), [Os(10)C(CO)(24)](2-), [Os(17)(CO)(36)](2-), [Os(20)(CO)(40)](3-), [Co(6)C(CO)(15)](2-), [Pt(3)Ru(10)C(2)(CO)(32)](2-) and [Pd(6)Ru(6)(CO)(24)](2-) have been analysed by energy-dependent electrospray ionisation mass spectrometry (EDESI-MS). Three main features have emerged. Firstly, carbonyl ligands are fragmented from clusters with compact metal cores in an orderly fashion, with each of the ions generated by CO loss having approximately equal intensity. Secondly, electron autodetachment takes place in multiply charged anionic clusters, but only after elimination of a large proportion of their carbonyl ligands. Thirdly, clusters with open metal cores do not undergo CO loss in an orderly fashion, but certain peaks are considerably less intense. The appearance of these low-intensity peaks is believed to signify polyhedral core rearrangements, with open clusters folding to form more compact geometries. In some cases, the gas-phase transformations observed by EDESI-MS mirror those that are known to take place in solution. 相似文献
110.
Viktor Yu. Kramarenko Tetyana A. Shantalil Iryna L. Karpova Kateryna S. Dragan Eleonora G. Privalko Valery P. Privalko Daniel Fragiadakis Polycarpos Pissis 《先进技术聚合物》2004,15(3):144-148
Polyimide (PI) nanocomposites prepared by the in situ generation of crosslinked organosilicon nanophase (ON) through the sol‐gel process were characterized by densities, thermally stimulated depolarization currents and dielectric relaxation spectroscopy. Both a looser molecular packing of PI chain fragments adjacent to the ON and a loose inner structure of the spatial aggregates of ON were assumed to be responsible for a non‐additive decrease of the experimental values of dielectric permittivity for the nanocomposites. The pattern of composition dependence of the apparent dielectric permittivity of the ON suggested a probability of a morphological change around the composition PAAS/MTS = 100/16 (presumably, a sort of percolation transition from small‐size, individual clusters into large‐size, infinite clusters). Thus, PI reinforced with the sol‐gel derived nanophase may have a reasonably good potential as low dielectric permittivity materials. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献