共查询到20条相似文献,搜索用时 78 毫秒
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取代苯乙炔的简便合成方法 总被引:2,自引:0,他引:2
取代苯乙炔的简便合成方法刘林,刘智勇,余俊梅,单书香(四川大学生物工程系,成都610064)苯乙炔及取代苯乙炔是一类重要的电子化工原料和有机合成中间体。随着研究的不断深入,近年来发现此类化合物在生物医学、医药和农药等领域有着十分广阔的应用前景。它们在... 相似文献
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本文介绍了羧酸或其酯还原成醇类的一些还原剂,主要介绍了环己甲醇的一些合成方法和其主要应用考虑到经济性问题,提出了由硼氢化钾或钠作为还原剂的合成路线。 相似文献
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在水相介质中,利用重氮化反应,研究了2,5-二氯苯胺与5-(2′-羟基-3′-萘甲酰胺基)-苯并咪唑-2-酮一步合成得到颜料棕25的制备工艺,并采用正交设计方案讨论了分散剂用量、反应温度和时间、介质的pH等因素对颜料着色力和色光的影响,得到的最佳工艺条件为:偶合过程中,分散剂的质量分数为2%(反应物总质量计),偶合介质的pH=6.5;颜料化过程中,温度为115 ℃,时间为15 h。该方法是一种清洁生产技术。 相似文献
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对催化剂醋酸锌负载体进行了筛选,并考察了CO2的通入、不同负载量以及催化剂用量对反应的影响,并对比固定化前后Zn(OAc)2/AC反应相同次数后的催化效果。通过实验确定活性炭为醋酸锌的最佳负载体,CO2的通入能够抑制副反应,且能够促进主反应,使苯氨基甲酸甲酯(MPC)选择性提高。同时确定Zn(OAc)2在活性炭上的最佳负载量为10%;当催化剂质量分数达到约7%时,转化率和产物的选择性达到最大值。与未固定化的Zn(OAc)2/AC的催化效果相比,固定化Zn(OAc)2/AC在苯胺转化率和产物的选择性方面都有显著的提高。 相似文献
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概述了分散聚合的特点及其机理,重点介绍了以水为介质的阳离子聚丙烯酰胺分散聚合研究进展。详细探讨了阳离子聚丙烯酰胺水分散聚合体系的组成,即单体、分散介质、分散剂、引发剂等因素对分散聚合的影响以及各组分之间的相互关系。 相似文献
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Synthesis of ZnO Microtubes by a Facile Aqueous Solution Process 总被引:1,自引:0,他引:1
Liwei Lin Hideo Watanabe Masayoshi Fuji Takeshi Endo Seiji Yamashita Minoru Takahashi 《Journal of the American Ceramic Society》2009,92(S1):S165-S167
Zinc oxide (ZnO) microtubes 1.0–2.5 μm in length, 300–500 nm in outer diameter, and 50–80 nm in wall thickness have been synthesized by a facile aqueous solution process, by simply dropping ammonia water into zinc chloride aqueous solution. This new method shows some advantages, such as synthesis under atmospheric pressure at a glass flask, low cost and easy control. The growth mechanism of ZnO microtubes is discussed in this paper. The different growth rates of ZnO crystal facets create the different crystallographic facets of hexagonal microtubes. And the polar structure results in the formation of ZnO microtubes for minimizing the spontaneous polarization energy. The dependence of morphologies of ZnO particles on the reaction temperature is also investigated. The scanning electron microscopy results show that the reaction temperature plays an important role in the morphologies of ZnO particles. 相似文献
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Ezgi Akceylan 《Polycyclic Aromatic Compounds》2016,36(5):801-816
This article demonstrates the synthesis of new water soluble calix[4]arenes (8) based catalyst and application in one-pot, three component Mannich reactions to catalyze reaction between aromatic ketones/aldehyde and amines to acquire β-Amino carbonyl compounds in appreciable yields at room temperature in aqueous media. 相似文献
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N-羟基邻苯二甲酰亚胺的简便合成 总被引:2,自引:1,他引:1
N-羟基邻苯二甲酰亚胺(NHPI)是一种重要的化工原料;文章以盐酸羟胺、甲醇钠和邻苯二甲酸酐为原料,以甲醇为溶剂,合成了NHPI;该法合成和分离步骤简单,合成产率高(84%),产物纯度高(98.5%);简要讨论了合成反应的原理,分析了影响合成和产物分离提纯的一些因素。 相似文献
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The starch-stabilized Ag nanoparticles were successfully synthesized via a reduction approach and characterized with SPR UV/Vis
spectroscopy, TEM, and HRTEM. By utilizing the redox reaction between Ag nanoparticles and Hg2+, and the resulted decrease in UV/Vis signal, we develop a colorimetric method for detection of Hg2+ ion. A linear relationship stands between the absorbance intensity of the Ag nanoparticles and the concentration of Hg2+ ion over the range from 10 ppb to 1 ppm at the absorption of 390 nm. The detection limit for Hg2+ ions in homogeneous aqueous solutions is estimated to be ~5 ppb. This system shows excellent selectivity for Hg2+ over other metal ions including Na+, K+, Ba2+, Mg2+, Ca2+, Fe3+, and Cd2+. The results shown herein have potential implications in the development of new colorimetric sensors for easy and selective
detection and monitoring of mercuric ions in aqueous solutions. 相似文献
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Komban Rajesh Kizhakkekilikoodayil Vijayan Baiju Mani Jayasankar Krishna Gopakumar Warrier 《Journal of the American Ceramic Society》2008,91(7):2415-2418
A facile aqueous sol–gel process is being reported for the first time for the synthesis of alumina–lanthanum phosphate (Al2 O3 –LaPO4 ) nanocomposite. X-ray diffraction (XRD) analysis confirms the absence of any reactive phase even after heating to 1600°C. Microstructural analysis reveals a mutually controlled grain growth and the XRD analysis shows that the crystallite size of LaPO4 is in the range of 5–7 nm, indicating the exceptional inhibition of grain growth as well as the nanostructure of the sintered composite. 相似文献