An Investigation of the Reaction between CH3Radicals and NO at High Temperatures
摘要:
AbstractThe reaction between CH3 radicals and NO was investigated behind incident shock waves at temperatures between 1800 and 2150 K and total densities near 2 · 10−6 mol cm−3. — The consumption of CH3 was followed by time‐resolved UV‐absorption measurements at λ = 216 nm. — A rate constant of 2·1010 cm3 mol−1 s−1 for the reactionat temperatures around 1900 K was determined. — An activation energy of about 85 kJ mol−1 is estimate
Association reaction of CH3 and NO: evidence for the involvement of the triplet surface
作者:Joanne W. Davies、Nicholas J. B. Green、Michael J. Pilling
DOI:10.1039/ft9918702317
日期:——
The rate constant for the CH3+ NO reaction has been measured by laser flash photolysis/absorption spectroscopy over the temperature range 296–509 K and at pressures of 25–600 Torr. The data have been analysed using a global variant of the Troe factorisation technique which provides parameters for the representation of k1(P, T) over the experimental range. In addition, a further global technique for analysing the experimental data, based on inverse Laplace transformation of k∞1(T), coupled with a master equation treatment, has been developed. The advantage of this approach is that it emphasises the relationship between the limiting high-pressure rate coefficient and the energy-dependent lifetime of the adduct. In the present reaction system, this approach enables the lowest triplet state to be implicated in the reaction; it is proposed that, following its formation, the triplet undergoes rapid intersystem crossing to the ground singlet state. The limiting rate parameters returned from the analysis are k∞1= 1.5 × 10–11 exp(–60 K/T) cm3 molecule–1 s–1, k01= 6.9 × 10–32 exp(1430 K/T) cm6 molecule–2 s–1, 〈ΔE〉down= 235 cm–1, for Ar as the diluent gas.
Gas phase reactions of Group 8-10 transition-metal ions with nitroalkanes
作者:C. J. Cassady、Ben S. Freiser
DOI:10.1021/ja00292a020
日期:1985.3
Les reactions de Fe + , Co + et Ni + avec les nitroalcanes sont etudiees par spectrometrie de masse avec transformee de Fourier
Les reactors de Fe + , Co + et Ni + avec les nitroalcanes sont etudiees par spectrometrie de masse avec transformee de Fourier
The reaction of nitromethane with hydrogen and deuterium atoms in the gas phase. A mechanistic study
作者:E. Lund Thomsen、Ole J. Nielsen、Helge Egsgaard
DOI:10.1016/0009-2614(93)89297-u
日期:1993.11
The mechanism of the reaction between H and CH3NO2, has been studied in a discharge flow system using electron paramagnetic resonance and modulated molecular beam mass spectrometry for the detection of reactants and products. Deuterium atoms have, in addition to CD3NO2, been used to support the proposed reaction mechanism. The reaction was studied with the atomic reactant in slight excess at 298 K
在放电流系统中,利用电子顺磁共振和调制分子束质谱法研究了H和CH 3 NO 2之间的反应机理,以检测反应物和产物。除了CD 3 NO 2以外,氘原子还用于支持拟议的反应机理。研究了在298 K和2 Torr的总压力下稍微过量的原子反应物对反应的研究。观察到两个同时发生的反应通道:(1a)H + CH 3 NO 2 →HONO + CH 3和(1b)H + CH 3 NO 2 →CH 3 NO + OH。支化比,k 1a/(k 1a + k 1b)为0.7±0.2
Quinazoline derivatives as acetylcholinesterase inhibitors
申请人:Warner-Lambert Company
公开号:US05486512A1
公开(公告)日:1996-01-23
A method of treating cognitive deficiencies is described by administering a quinazoline derivative of the general formula ##STR1## wherein A represents ##STR2## in which n is 1-10, P is a bond or (CH.sub.2).sub.m in which m is 0-10, and M is .dbd.O, .dbd.S, .dbd.NR, .dbd.CRR', ##STR3## novel compounds of the above are also described as well as methods of manufacture and pharmaceutical compositions.
Mechanistic Study of the Selective Catalytic Reduction of Nitric Oxide with Methane over Yttrium Oxide
作者:Mark D. Fokema、Jackie Y. Ying
DOI:10.1006/jcat.2000.2814
日期:2000.5
observed trends in catalyticproperties. Methyl radicals generated at the catalyst surface desorb into the gas phase, where they react with nitric oxide to form nitrosomethane. Nitrosomethane then decomposes in a series of homogeneous and heterogeneous reactions to produce nitrogen and nitrous oxide. Evidence for gas-phase reaction of methyl radicals with nitric oxide was found in the adsorption studies of