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381.
Gándara F Uribe-Romo FJ Britt DK Furukawa H Lei L Cheng R Duan X O'Keeffe M Yaghi OM 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(34):10595-10601
A new family of porous crystals was prepared by combining 1H-1,2,3-triazole and divalent metal ions (Mg, Mn, Fe, Co, Cu, and Zn) to give six isostructural metal-triazolates (termed MET-1 to 6). These materials are prepared as microcrystalline powders, which give intense X-ray diffraction lines. Without previous knowledge of the expected structure, it was possible to apply the newly developed charge-flipping method to solve the complex crystal structure of METs: all the metal ions are octahedrally coordinated to the nitrogen atoms of triazolate such that five metal centers are joined through bridging triazolate ions to form super-tetrahedral units that lie at the vertexes of a diamond-type structure. The variation in the size of metal ions across the series provides for precise control of pore apertures to a fraction of an Angstrom in the range 4.5 to 6.1??. MET frameworks have permanent porosity and display surface areas as high as some of the most porous zeolites, with one member of this family, MET-3, exhibiting significant electrical conductivity. 相似文献
382.
A metal-organic great rhombicuboctahedron (termed MOP-18) was functionalized with extended alkyl chains and crystallized. It has 12 rigid square-shaped Cu2(CO2)4 paddle-wheel building units and 24 5-dodecoxybenzene-1,3-dicarboxylate links. MOP-18 is soluble in a variety of organic solvents, such as tetrahydrofuran, chloroform, and toluene, which enabled its assembly on graphite substrate and its observation by scanning tunneling microscopy. 相似文献
383.
Hideki Taguchi Kazuhiro Hirata Hiroyasu Kido Yasuo Takeda Masaki Kato Ken Hirota 《Solid State Sciences》2009,11(7):1222-1225
Orthorhombic distorted K2NiF4-type (Ca1+xNd1?x)CrO4 (0.00 ≤ x ≤ 0.15) was synthesized using a standard ceramic technique. The cell parameters (a and c) decreased, whereas the cell parameter (b) increased with the increase in x. The variation in the global instability index (GII) indicated that the crystal stability of (Ca1+xNd1?x)CrO4 was not influenced by the Cr4+ ion content. At all temperatures, the electrical conductivity (σ) of (Ca1+xNd1?x)CrO4 increased with the increase in x. (Ca1+xNd1?x)CrO4 was a p-type semiconductor and exhibited hopping conductivity in a small-polaron model in the temperature range of 290 K ≤ T ≤ 713 K. The Cr4+ ion acts as an acceptor, and the electron transfer through the Cr3+–O–Cr4+ path becomes active as a result of the Cr4+ ion content and the Cr–O(1) distance. 相似文献
384.
385.
Hiyori Komatsu Shiharu Watanabe Shima Ito Kazuhiro Nagasaka Akihiro Nishiguchi Tetsushi Taguchi 《Macromolecular bioscience》2023,23(7):2300097
Adhesives/sealants are used after suturing to prevent leakage of cerebrospinal fluid from an anastomotic site. Commercial adhesives/sealants have been used to close the cerebral dura. However, swelling of the cured adhesives/sealants induces increased intracranial pressure and decreases the strength of the seal. In the present study, tissue adhesive hydrogels with improved swelling property using inclusion complex composed of α-cyclodextrin (αCD) and decyl group (C10)-modified Alaska pollock-derived gelatin (C10-ApGltn) with a high degree of substitution (DS) (>20 mol%) are developed. Viscosity of C10-ApGltn with a high DS solution remarkably decreased by the addition of αCD. The resulting αCD/C10-ApGltn adhesive hydrogel composed of αCD/C10-ApGltn inclusion complexes and poly(ethylene glycol) (PEG)-based crosslinker showed improved swelling property after immersion in saline. Also, the resulting adhesive has a significantly higher burst strength than fibrin-based adhesives and is as strong as a PEG-based adhesive. Quantitative analysis of αCD revealed that the improved swelling property of the resulting adhesive hydrogels is induced by the release of αCD from cured adhesive, and the subsequent assembly of decyl groups in the saline. These results suggest that adhesives developed using the αCD/C10-ApGltn inclusion complex can be useful for closing the cerebral dura mater. 相似文献
386.
Takumi Mizuno Ikuzo Nishiguchi Tsuneaki Hirashima Noboru Sonoda 《Heteroatom Chemistry》1990,1(2):157-159
Carbon oxide sulfide was easily generated upon heating of amine salts of carbamothioic acids at 85°C which were produced in situ from amines, carbon monoxide, and elemental sulfur in the presence of a catalytic amount of selenium under mild conditions. 相似文献