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The structures of the complexes formed between N-methylol ethanone(model molecule of ceramide) and azacyclopentane-2-one(the model molecule of azone) have been fully optimized at the B3LYP/6-311++G** level.The intermolecular hydrogen bonding interaction energies have been calculated by using the B3LYP/6-311++G**,B3LYP/6-311++G(2df,2p),MP2(full)/6-311++G** and MP2(full)/6-311++G(2df,2p) methods,respectively.The results show that strong O–H···O=C,N–H···O=C and C–H···O=C hydrogen bonds could exist between azacyclopentane-2-one and N-methylol ethanone.The formation of the complexes might change the conformation of ceramide molecule and thus cause better percutaneous permeation for the drugs.This is perhaps the origin of the permeation enhances the activity of azone for medicament,as is in accordance with the experimental results.The hydrogen-bonding interactions follow the order of(a) (c) (b) (d) (g) ≈(e) ≈(i) (h) (f).The analyses of frequency,NBO,AIM and electron density shift are used to further reveal the nature of the complex formation.In the range of 263.0~328.0 K,the complex is formed via an exothermic reaction,and the solvent with lower temperature and dielectric constant is favorable to this process. 相似文献
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发展一类新的光谱分析方法--声致发光法 总被引:1,自引:1,他引:0
声致发光是超声波空化效应在溶液中引发的次级效应,上个世纪80年代起,研究人员开始将这一新的发现应用于化学分析、医学检验与环境监测。本文论述了包括作者在内的研究者在该领域的研究进展,主要包括声致发光在癌症监测中的应用,作为一种新型的原子发射光谱在元素分析中的应用以及推广于环境监测分析中的情况。 相似文献
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