共查询到20条相似文献，搜索用时 453 毫秒
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杯芳烃作为第三代超分子主体化合物,近20年来引起了广泛的研究.由于杯芳烃的研究领域十分广泛,为更深入全面地理解杯芳烃的结构、选择性的关系和起源,为合成更为有效的杯芳烃受体,本文仅就杯芳烃母体、上下缘修饰杯芳烃和阴阳离子、中性有机分子的配位作用的热力学行为及应用的相关技术进行述评. 相似文献
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杯芳烃及其衍生物能选择性地与某些分子、阳离子、阴离子发生分子识别作用。本文综述了近年来开拓的杯芳烃及其衍生物的手性识别性能,预期了其应用前景。 相似文献
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通过杯[6]芳烃六乙酸乙酯与多乙烯多胺进行氨解反应,合成了系列酰胺型杯[6]芳烃聚合物,它们对软金属离子具有较高的吸附容量,其吸附能力与聚合物中杯芳烃的含量成正比,在吸附过程中杯芳烃单元起决定性作用． 相似文献
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对叔丁基杯芳烃合成及性能研究的综合实验 总被引：3，自引：0，他引：3
文中对叔丁基杯芳烃的合成和性质研究设计为本科生综合实验。用对叔丁基苯酚和37%的甲醛在碱性条件下合成了对叔丁基杯[4]芳烃、对叔丁基杯[6]芳烃和对叔丁基杯[8]芳烃,并对三种产物进行了结构检测,还比较了三种杯芳烃对铜离子萃取能力的大小。 相似文献
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研究了乙酰异丙胺基取代和丁基取代杯[4]芳烃聚硅氧烷固定相的合成.按此合成路线得到的杯芳烃衍生物产率高,约为60%. 相似文献
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林洪梅 《沈阳教育学院学报》1999,(Z1)
杯芳烃是由苯酚和甲醛在酚羟基邻位缩合而成的一类大环化合物.因为它是由多个苯环构成的芳香族分子,且分子形状酷似希腊圣杯,由此得名杯芳烃.杯芳烃的命名习惯上写成“杯[n]芳烃”.n为苯酚环的个数.例如对位由特丁基取代的环状四聚体写成“对特丁基杯[4]芳烃”.如果取代基较复杂时,可根据Chemical Abstract方式,按图1中的编号进行命名.如上述化合物可命名为“5,11,17,23—四特丁 相似文献
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以Pn^2＋为模板分子，以巯基壳聚糖为功能单体合成了交联巯基壳聚糖分子印迹聚合物．并研究其合成、吸附和洗脱条件，结果表明：合成的分子印迹聚合物抗酸性提高了，且保留了对Pb^2＋良好的吸附性和识别选择性． 相似文献
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近年来形成了以选择性分子识别为主要内容的“主—客体化学”和“超分子化学”.美国加州大学的克拉姆教授是“主—客化学”的创立者;法国路易·巴斯德大学的莱蒽教授是“超分子化学” 的创立者.他们为此而荣获1987年诺贝尔化学奖.本文介绍了“环糊精”、“大环多醚”、“杯芳烃”、“卟啉”四类能形成主客体配合物,具有选择性识别功能的大环化合物及其应用. 相似文献
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《海外英语》2007,(5):10-11
Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help? 相似文献
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邱崇丙 《唐山师范学院学报》2014,(1):21-23
汉字的六书,《说文》对“转注”一类,语焉不详。后世学者提及转注,也仅限于许慎所举出的例字。《汉字例说》一文,作者从转注的角度综合考虑,对部分现代常用字作了分析,跟传统的解释有所不同。希望能抛砖引玉,互相切磋,以推进学术研究。 相似文献
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《海外英语》2007,(4):36
There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love. 相似文献
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Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject. 相似文献
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Rachel Zupek 《海外英语》2007,(11):40-41
我们绝大部分人都同意一件事情——我们喜欢金钱。但是你对金钱的喜欢之情足够到让你创立一份事业么?.财富通常被人忽视,主要在于人们不能真正了 相似文献
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Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities. 相似文献
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RUZBEHANI Mohsen 《重庆大学学报(英文版)》2004,3(1):20-25
1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec… 相似文献