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用^1H NMR测定吡啶和2,6—二甲基吡啶的pKα和热力学参数
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作者 杨绪杰 黄海荣 +3 位作者 刘劲松 刘孝恒 陆路德 汪信 《波谱学杂志》 CAS CSCD 北大核心 1997年第6期485-490,共6页
实验中配制一系列不同pH值的吡啶和2,6-二甲基吡啶的水溶液,用80MHz核磁共振谱仪测定每个pH点的核磁共振图谱.根据平衡常数与pH值及离子浓度的关系,可以计算出pKα的值.改变体系的实验温度,可以得到热力学参数△H、△S和△G的值... 实验中配制一系列不同pH值的吡啶和2,6-二甲基吡啶的水溶液,用80MHz核磁共振谱仪测定每个pH点的核磁共振图谱.根据平衡常数与pH值及离子浓度的关系,可以计算出pKα的值.改变体系的实验温度,可以得到热力学参数△H、△S和△G的值.研究结果表明,核磁共振的方法是可靠的,它比传统的pH滴定方法测定pKα值的方法简单得多. 展开更多
关键词 NMR 杂环碱化合物 pKα 热力学参数 吡啶
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Supercritical Water as a Reaction Medium for Nitrogen-Containing Heterocycles 被引量:1
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作者 Wahyudiono Yui Matsunaga +2 位作者 Siti Machmudah Mitsuru Sasaki Motonobu Gotol 《Journal of Chemistry and Chemical Engineering》 2012年第10期897-910,共14页
Supercritical water has been focused on as an environmentally attractive reaction media, in which organic materials can be decomposed into smaller molecules. The reaction behavior of pyrrole as a simple model compound... Supercritical water has been focused on as an environmentally attractive reaction media, in which organic materials can be decomposed into smaller molecules. The reaction behavior of pyrrole as a simple model compound of nonbasic nitrogen compounds found in petroleum residua was studied in supercritical water with a batch type reactor. The reaction was carried out at temperatures of 698-748 K and at various pressures under an argon atmosphere. The chemical species in the aqueous products were identified by GCMS (gas chromatography mass spectrometry) and quantified using GC-FID (gas chromatography flame ionization detector). The effect of temperature and reaction time on the conversion process of pyrrole is presented. Under supercritical water conditions, pyrrole underwent successful decomposition in water into its derived compounds. The conversion of pyrrole could approach 81.12 wt% at 723 K and 40 MPa within 240 min of reaction time. The decomposition process was accelerated with the existence of water at the same temperature. Ultimate analysis of solid products was also conducted using a CHN analyzer. The process investigated in this study may form the basis for an efficient method of nitrogen compound decomposition in future. 展开更多
关键词 Supercritical water PYRROLE HYDRODENITROGENATION non-basic aromatic nitrogen compound conversion.
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Molecular Simulation Studies on Basicity of Nitrogen-containing Compounds
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作者 Wang Lixin Zhou Han +1 位作者 Dai Zhenyu Shen Xizhou 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2009年第3期62-67,共6页
The DFT-based (density fimctional theory) ab initio quantum mechanical methods have been applied to study the basicity of the nitrogen-containing compounds in petroleum. The results have indicated that there is a di... The DFT-based (density fimctional theory) ab initio quantum mechanical methods have been applied to study the basicity of the nitrogen-containing compounds in petroleum. The results have indicated that there is a distinct relationship between the protonation energy of nitrogen-containing compounds and their basicity. The more negative the protonation energy, the stronger the basicity is. It has been also found that aliphatic amines are more basic than pyridines or aromatic amines, and all these compounds are more basic than pyrroles. The addition of the aromatic rings can influence the basicity of anilines, while the 5- and 6-membered heterocyclic compounds function differently. The solvent properties may affect the basicity of these nitrogen-containing compounds. 展开更多
关键词 nitrogen-containing compounds BASICITY quantum mechanics molecular simulation solvent effect
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