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Widening Synthesis Bottlenecks: Realization of Ultrafast and Continuous‐Flow Synthesis of High‐Silica Zeolite SSZ‐13 for NOx Removal 下载免费PDF全文
Zhendong Liu Prof. Dr. Toru Wakihara Dr. Kazunori Oshima Daisuke Nishioka Yuusuke Hotta Dr. Shanmugam P. Elangovan Yutaka Yanaba Prof. Dr. Takeshi Yoshikawa Dr. Watcharop Chaikittisilp Takeshi Matsuo Takahiko Takewaki Prof. Dr. Tatsuya Okubo 《Angewandte Chemie (International ed. in English)》2015,54(19):5683-5687
Characteristics of zeolite formation, such as being kinetically slow and thermodynamically metastable, are the main bottlenecks that obstruct a fast zeolite synthesis. We present an ultrafast route, the first of its kind, to synthesize high‐silica zeolite SSZ‐13 in 10 min, instead of the several days usually required. Fast heating in a tubular reactor helps avoid thermal lag, and the synergistic effect of addition of a SSZ‐13 seed, choice of the proper aluminum source, and employment of high temperature prompted the crystallization. Thanks to the ultra‐short period of synthesis, we established a continuous‐flow preparation of SSZ‐13. The fast‐synthesized SSZ‐13, after copper‐ion exchange, exhibits outstanding performance in the ammonia selective catalytic reduction (NH3‐SCR) of nitrogen oxides (NOx), showing it to be a superior catalyst for NOx removal. Our results indicate that the formation of high‐silica zeolites can be extremely fast if bottlenecks are effectively widened. 相似文献
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《中国化学》2017,35(7):1050-1056
Crown ether usually plays the role of macrocyclic host in supramolecular chemistry, but here the crown ether is also utilized as the stoppers in rotaxanes. In this work, we designed and synthesized two [3]rotaxanes containing four crown ether components by using an approach of template‐directed clipping reaction, of which, two crown ether components were employed as the macrocyclic hosts to assemble the mechanically interlocked framework while another two crown ether units located on the two ends of ammonium template acting as the stoppering groups of rotaxanes. Their self‐assembling process was monitored by the 1H NMR and one of the single crystal structures of [3]rotaxane was obtained. 相似文献
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由(+)-2-氨基丁醇合成氮杂手性冠醚 总被引:2,自引:0,他引:2
手性冠醚由于具有手性识别和不对称催化有机反应的性质而受到人们的重视,有关它们的合成及性质,已很多论述。氮杂冠醚则是合成穴醚、双冠醚、套索冠醚(LariatEther)等的重要中间体,也可与高分子材料(高分子载体或高分子基质)连接,用于有机化合物的色谱分离。氮杂手性冠醚兼备手性和氮杂冠醚两种特性,而可能具有广泛的用途。 相似文献
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Jordi Casanovas Dr. Julien Preat Dr. David Zanuy Dr. Carlos Alemán Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(18):4676-4684
Tuning sensing abilities! The affinity of three different [15]crown‐5 ether functionalized polythiophenes for alkali ions has been explored (see figure). Ab initio and DFT quantum mechanical calculations show that the binding energy between neutral conducting polymers and metallic ions, which interact attractively, decreases as the size of the ion increases. Oxidation of these polythiophene derivatives significantly reduces their affinity towards alkali ions, becoming low or even nonexistent.
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报道了4-氮杂15--5-4'-甲氮基偶氮苯和4-氮杂15-冠-5-4'-硝基偶氮苯的合成及其分子内扭曲电荷转移的光致变色机理。 相似文献
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高效液相色谱氮杂冠醚键合固定相的合成及性能研究 总被引:2,自引:0,他引:2
我们曾用γ-氯丙基键合硅胶(CPS),在氢化钠(NaH)作用下合成了3-(氮杂-18-冠-6)丙基键合固定相(BCP)[1].该固定相对碱基、核苷酸、硝基苯酚等有较好的分离选择性,但由于NaH对硅胶基质腐蚀作用较大,导致BCP柱效及渗透性较低.本文采... 相似文献
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二氧化硅固载硫、氮杂冠醚铂配合物的合成及其催化烯烃硅氢化性能 总被引:1,自引:0,他引:1
二(β-氯乙基)烯丙胺与3,6-二氧杂辛-1,8-二硫醇在乙醇钠存在下关环缩合,得到具有烯基侧链的1,7-二硫杂-10,13-二氧杂-4-氮杂-4-烯丙基环十五烷.后者通过硅氢加成、二氧化硅固载.再与氯亚铂酸钾反应,合成了一种新型有机硅聚合物负载硫、氮杂冠醚及其铂配合物.该配合物对于烯烃硅氢加成反应具有良好的催化性能. 相似文献
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合成了冠醚3,3′-二甲基二苯并-18-冠-6(MDB18-C-6),并以该化合物为配体分别与镍(Ⅱ)、钯(Ⅱ)和K2(i-mnt)作用,进一步合成了配合物[K(MDB18-C-6)(CH3COCH3)]2[Ni(i-mnt)2](1)及配合物[K(MDB18-C-6)(CH3SOCH3)]2[Pd(i-mnt)2](2)。通过元素分析、红外光谱、紫外光谱、核磁共振氢谱、质谱等测试手段对其结构进行表征,用X-射线单晶衍射测定了配合物1和配合物2的晶体结构。利用紫外吸收光谱、荧光光谱和圆二色光谱等光谱分析法研究了配合物与小牛胸腺DNA(CT-DNA)的作用,结果表明两种配合物与DNA都具有相互作用,配合物主要是通过影响DNA的螺旋结构,从而引起DNA的构象变化,并且配合物2的作用性能大于配合物1。 相似文献
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合成了冠醚3,3’-二甲基二苯并-18-冠-6(MDB18-C-6),并以该化合物为配体分别与镍(Ⅱ)、钯(Ⅱ)和K2(i-mnt)作用,进一步合成了配合物[K(MDB18-C-6)(CH3COCH3)]2[Ni(i-mnt)2](1)及配合物[K(MDB18-C-6)(CH3SOCH3)]2[Pd(i-mnt)2](2)。通过元素分析、红外光谱、紫外光谱、核磁共振氢谱、质谱等测试手段对其结构进行表征,用X-射线单晶衍射测定了配合物1和配合物2的晶体结构。利用紫外吸收光谱、荧光光谱和圆二色光谱等光谱分析法研究了配合物与小牛胸腺DNA(CT-DNA)的作用,结果表明两种配合物与DNA都具有相互作用,配合物主要是通过影响DNA的螺旋结构,从而引起DNA的构象变化,并且配合物2的作用性能大于配合物1。 相似文献
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Metal‐Free and Alkali‐Metal‐Catalyzed Synthesis of Isoureas from Alcohols and Carbodiimides 下载免费PDF全文
Arnaud Imberdis Dr. Guillaume Lefèvre Dr. Pierre Thuéry Dr. Thibault Cantat 《Angewandte Chemie (International ed. in English)》2018,57(12):3084-3088
The first addition of alcohols to carbodiimides catalyzed by transition‐metal‐free compounds employs 1,5,7‐triazabicyclo[4.4.0]dec‐5‐ene (TBD) and its alkali metal salts. Isoureas are obtained in short reaction times and high yields when TBDK is used as the catalyst. Control of the coordination sphere of potassium with exogenous chelating ligands, in combination with mechanistic DFT calculations, demonstrated the role and positive influence of the alkali‐metal cation on the kinetics. 相似文献
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WeiZENG ZhiHuaMAO MiGONG ChunChunZHANG ShengYingQIN JunSU 《中国化学快报》2003,14(8):786-789
N-pivot lariat ethers with picrylamino group as a chromophore (1, 2 and 3) have been prepared by reaction of N-(4-aminoaryl)monoaza crown ethers with picryl chrolide,and the selective coloration of 1, 2 and 3 for alkali metal salts and amines has been studied by UV-Vis spectra. 相似文献
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合成了开链冠醚Schiff碱配体H2L(H2L=N,N′-双(邻羟苯亚甲基)-3,6-二氧杂-1,8-二氨基辛烷).详细研究了该配体在不同溶剂中和过渡金属离子存在下的荧光光谱,探讨了溶剂极性和不同金属离子对其荧光光谱的影响.结果表明:溶剂的极性和金属离子对其荧光性质有较大影响,随着溶剂极性的减小,配体的荧光增强,且谱峰发生蓝移.金属离子Zn2+、Cd2+对配体具有荧光增敏作用,Ni2+、Cu2+具有荧光猝灭作用.探讨了配体与金属离子结合的pH范围,结果显示最佳pH值为7—8. 相似文献