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61.
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Kazuki Nakanishi Yosuke Sato Yayat Ruyat Kazuyuki Hirao 《Journal of Sol-Gel Science and Technology》2003,26(1-3):567-570
Silica gels with hierarchical macropores and mesopores have been prepared by inducing phase separation in the alkoxide-based sol-gel system with an addition of alkyltrimethylammonium salt. Narrowly distributed mesopores were observed in the heat-treated gel samples possibly as a result of supramolecular templating of silica oligomers in the reacting solution. The ionic attractive interaction and hydrophobicity of the attached alkyl group cooperatively determined the phase separation tendency. No indication of long-range order of the mesopores was obtained. 相似文献
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This review supplied direct insight of host-guest molecule system by using COR as the guest molecule. 相似文献
65.
Yu Na Lim Soo Kyung Chae Woongbin Yim Ji‐Yong Park Woojin Yoon Hoseop Yun Eunha Kim Seung Uk Son Hye‐Young Jang 《应用有机金属化学》2019,33(3)
The reaction of [(domppp) Pd (OAc)2] [domppp = 1,3‐bis (di‐o‐methoxyphenylphosphino)propane] and imidazolium‐functionalized carboxylic acids containing various anions (Br?, PF6?, SbF6? and BF4?) resulted in the formation of nano‐sized Pd (II) aggregates under template‐free conditions. The rate of formation of aggregates can be modulated by changing the anion, affecting the rate of polymerization of CO and olefins without fouling. Herein, we describe the analysis of Pd (II) catalysts by dynamic light scattering, atomic force microscopy, X‐ray photoelectron spectroscopy and X‐ray crystallography, and co‐ and terpolymerization results including the catalytic activity, and bulk density and molecular weight of polymers. 相似文献
66.
以树形分子为模板制备银纳米颗粒 总被引:14,自引:3,他引:14
以硝酸银为原料,硼氢化钠为还原剂,PAMAM树形分子为模板兼稳定剂,制备出粒径分布范围在4~7mm的银纳米颗粒.实验发现,其他条件相同时,银纳米颗粒的粒径随着Ag^ /树形分子摩尔比的增加而增加,并且树形分子代数越高,所起的模板作用越显著.还研究了溶液pH值的影响,发现当溶液pH值在7左右时,可以制得粒径较小、分散性较好的银纳米颗粒.用紫外-可见光谱,透射电镜(TEM)以及原子力显微镜(AFM)等测试手段对所制得的银纳米颗粒进行了表征. 相似文献
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1 INTRODUCTION The crystal structures of several tetrahalogeno-mercurates (II) have been reported with a wide va-riety of stereochemical arrangements[1, . These stu- 2]dies have shown that the Hg atom… 相似文献
69.
The construction of two unique, high-nuclearity Cu(II) supramolecular aggregates with tetrahedral or octahedral cage units, [(mu(3)-Cl)[Li subset Cu(4)(mu-L(1))(3)](3)](ClO(4))(8)(H(2)O)(4.5) (1) and [[Na(2) subset Cu(12)(mu-L(2))(8)(mu-Cl)(4)](ClO(4))(8)(H(2)O)(10)(H(3)O(+))(2)](infinity) (2) by alkali-metal-templated (Li(+) or Na(+)) self-assembly, was achieved by the use of two newly designed carboxylic-functionalized diazamesocyclic ligands, N,N'-bis(3-propionyloxy)-1,4-diazacycloheptane (H(2)L(1)) or 1,5-diazacyclooctane-N,N'-diacetate acid (H(2)L(2)). Complex 1 crystallizes in the trigonal R3c space group (a = b = 20.866(3), c = 126.26(4) A and Z = 12), and 2 in the triclinic P1 space group (a = 13.632(4), b = 14.754(4), c = 19.517(6) A, alpha = 99.836(6), beta = 95.793(5), gamma = 116.124(5) degrees and Z = 1). By subtle variation of the ligand structures and the alkali-metal templates, different polymeric motifs were obtained: a dodecanuclear architecture 1 consisting of three Cu(4) tetrahedral cage units with a Li(+) template, and a supramolecular chain 2 consisting of two crystallographically nonequivalent octahedral Cu(6) polyhedra with a Na(+) template. The effects of ligand functionality and alkali metal template ions on the self-assembly processes of both coordination supramolecular aggregates, and their magnetic behaviors are discussed in detail. 相似文献
70.
Summary: A new calix[4]arene‐based periodic mesoporous organosilica has been synthesized using tetraethoxysilane (TEOS) and a calix[4]arene‐based silane monomer as the precursors and cetyltrimethylammonium bromide (CTAB) surfactant as the structure‐directing template, and is shown to be capable of visual detection and entrapment of NO2.