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931.
Recent advances in the study of short-lived reactive resonances are reviewed. Special emphasis is given to addressing the
question of how reactive resonances might be observed in molecular beam scattering experiments. Three case studies are presented
for simple triatomic systems that are believed to exhibit resonance phenomena: F + HD → D + HF, F + H2 → H + HF, and H + HD → D + H2. It is seen that reactive resonances do strongly influence collision observables, but in a different way for each case. At
this stage, there does not appear to be a unique resonance signature that can be applied to all reactions.
Received: 2 March 2002 / Accepted: 2 June 2002 / Published online: 17 October 2002
Acknowledgements. For their valuable input into the research discussed here, we are grateful to our collaborators, K. Liu, S.H. nk;Lee, F.
Dong, D.E. Manolopoulos, D, Skouteris, X. Yang, S. Harich, D. Dai, and C.C. Wang. This work was supported by the National
Science Foundation.
Correspondence to: R. T. Skodje e-mail: skokje@spot.colorado.edu 相似文献
932.
933.
盛平兴 《应用数学与计算数学学报》1996,10(1):67-72
本文讨论两点边值问题解的存在性,在没有孤立性条件下,获得了不动点定理,作为应用实例,给出了反应扩散方程稳态解的存在性证明。 相似文献
934.
935.
Gui Sheng DENG Ming Yi LIAO Xue TIAN Jian Bo WANG Key Laboratory of Bioorganic Chemistry Molecular Engineering of Ministry of Education College of Chemistry Peking University Beijing 《中国化学快报》2005,(5)
The nucleophilic addition to α, β-unsaturated carbonyl compounds is a fundamental C-C bond forming reaction in organic chemistry1. Since there are two reaction sites in the α, β–unsaturated carbonyl group, the regioselectivity of the nucleophilic addition (1, 2 vs. 1, 4 addition) is of primary importance when applying this type of reaction in organic synthesis. Factors that control the regioselectivity include the softness and hardness of the attacking nucleophiles2, solvent and temperatu… 相似文献
936.
A New Alkaloid from Sinomenium acutum 总被引:2,自引:0,他引:2
Wei Ming CHENG Feng QIU Li Jun WU Xin Sheng YAO 《中国化学快报》2005,16(11):1481-1483
Sinomenium acutum is widely used in East and South Asia for the treatment of many diseases, especially rheumatoid arthritis (RA). The chemical research on Sinomenium acutum led to the isolation of a new alkaloid compound (1). On the basis of chemical evidences and spectral analysis, 1 was identified as N-(1, 7-dimethoxylphenanthren-2-yl)acetamide. 相似文献
937.
Wei XIE Fu Sheng NIE Meng Long LI Guang Ming LI Min Chun LU 《中国化学快报》2006,17(7):929-932
This paper studies various classifiers to identify primary, secondary or tertiary alcohols by using segmental spectra and their combinations to support vector machines (SVMs). The results showed that the O-H in-plane bending absorption contributed most to identification their substitute. This conclusion disagrees with related known research results. 相似文献
938.
The electric transport character in heterojunction composed of a La0.7Ce0.3MnO3 film and a 0.5 wt% Nb-doped SrTiO3 substrate (LCEM/STON) is investigated. It is found that the energy band gap (Eg) between LCEM and STON decreases with increasing temperatures. The most striking observation of present work is that there exists a variation of reverse transport mechanism from ionization to tunneling at the temperature of 175 K. We attribute the temperature dependence of reverse transport mechanism to co-work of Eg and the ferromagnetic (FM) insulting phase in the heterojunction. These results are helpful in configuring artificial devices using manganites. 相似文献
939.
940.
Using orthogonal protection-deprotection glycosylation strategy, a series of diosgenyl glycosides with same of monosaccharides component but different in sequence were synthesized. The antitumor activity in vitro of synthesized diosgenyl glycosides was evaluated by standard MTT assay. It was observed that diosgenyl glycosides with a rhamnopyranosyl at C2′ of glucopyranosyl residue show potent antitumor activity in vitro. 相似文献