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Preparation and Spectroscopic Study of Different Stoichiometric Solid Supramolecular Inclusion Complexes of β-Cyclodextrin with Short Chain Aliphatic Amines 被引量:1
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作者 Le-xin Song Chuan-feng Teng +1 位作者 Hai-ming Wang Lei Bai 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2008年第2期174-180,共7页
The solid Supramolecular complexes of β-cyclodextrin (β-CD) with ethylenediamine 1, diethylenetriamine 2 and triethylamine 3 were obtained and characterized using elemental analysis, powder X-ray diffraction, infr... The solid Supramolecular complexes of β-cyclodextrin (β-CD) with ethylenediamine 1, diethylenetriamine 2 and triethylamine 3 were obtained and characterized using elemental analysis, powder X-ray diffraction, infrared spectroscopy, thermogravimetric analysis, and ^1H nuclear magnetic resonance spectroscopy. Based on the results of elemental analysis and ^1H NMR, the guest-host stoichiometries of the three solid complexes were determined to be 5:2 for 1-β-CD, hl for 2-β-CD, and 1:3 for 3-β-CD. The yields were relative to the molar volume ratio of guest to β-CD cavity, and increased in the order: 1-β-CD〈2-3-CD〈3-β-CD. X-ray diffraction patterns of the inclusion complexes gave very good exhibitions not only in location of diffraction peaks but also in shape and diffraction intensity of the peaks due to the intermolecular complexations between β-CD and the guests. The formation of host-guest inclusion complexes exhibited obviously enhanced phase change temperatures of the complexed guests such as 1 and 3. The H-5 protons located at the narrower rim inside the CD cavity experienced a higher shift upon inclusion while all other protons experienced lower shifts. 展开更多
关键词 Β-CYCLODEXTRIN Inclusion complex ETHYLENEDIAMINE SUPRAMOLECULAR
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答案题丰富多彩
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作者 徐金明 《数理化学习(高中版)》 2004年第11期45-46,共2页
“物质结构 元素周期律”一章中有许多习题的答案是不唯一的。它不仅能考查学生思维能力的深刻性,而且能培养学生的思维品质。有利于教学,也有利于高校选拔人才.下面举例说明.
关键词 “物质结构 元素周期律” 化合物化学式 习题 高中 化学 解法 答案
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