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781.
Shu‐Jin Li De‐Chun Zhang Zhong‐Lin Huang Yan‐Qiu Zhang Kai‐Bei Yu 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(9):1122-1123
In the cation of the title compound, C15H16NO+·C24H20B?, the pyridyl ring makes a dihedral angle of 14.03° with the phenyl ring. The anion has a slightly distorted tetrahedral geometry and forms honeycomb‐like sheets which extend along the b axis, forming channels containing the cations. A comparison of packing energies reveals a difference between the title compound and a similar material which has non‐linear optical properties. 相似文献
782.
Uwe‐Christoph Knig Michael Berkei Claudia Hirsch Hans Preut Terence Nigel Mitchell 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(12):e550-e551
The preparation and X‐ray analysis of the title compound, [Sn2Br4(CH3)4(C5H9NO)], are described. The compound contains two Sn atoms in the asymmetric unit, that complexed by N‐methylpyrrolidin‐2‐one being hexacoordinated (a), the other exhibiting pentacoordination (b). The most important features are three different Sn—Br bond lengths at both Sn atoms with the following values: (a) 2.5060 (9), 2.7152 (10) and 3.7118 (10) Å; (b) 2.5084 (10), 2.5279 (9) and 3.5841 (10) Å. 相似文献
783.
Hao Zhang Jiwen Cai Guang Yang Gen‐Qiang Xue Liang‐Nian Ji 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(12):e562-e563
Colourless prismatic crystals of the title compound, [Cd(tren)(phen)](NO3)2·H2O [phen = 1,10‐phenanthroline, C12H8N2; tren = tris(2‐aminoethyl)amine, C6H18N4], form from an aqueous solution of equivalent amounts of Cd(NO3)2, tren and phen. Infinite one‐dimensional polymeric zigzag motifs, constructed via alternating hydrogen‐bonding and π–π interactions, are further mediated by nitrate–amine hydrogen bonds to create three‐dimensional networks. 相似文献
784.
785.
Hongyuan Wang Toshinari Ugomori Yong Wang Kazuhiro Tanaka Hidetoshi Kita Ken‐Ichi Okamoto Yasunori Suma 《Journal of Polymer Science.Polymer Physics》2000,38(13):1800-1811
Poly(ethylene oxide imide) segmented copolymer (PEO‐PI) membranes were crosslinked by the chemical reaction between ethylene glycol diglycidyl ether and benzylalcohol groups of diamine moieties in polyimide segments at high temperatures. Sorption and diffusion of penetrants took place in poly(ethylene oxide) segment microdomains. Sorption and desorption behavior of pure vapors such as benzene (Bz), cyclohexane (Cx) and n‐hexane (Hx) was classified as the Fickian diffusion. Sorption isotherms of binary liquid mixtures could be represented by the Flory–Rehner model, but the model overpredicted the sorption amounts of Cx and Hx, leading to small predictions of sorption selectivity αS for Bz/Cx and Bz/Hx systems. UNIFAC‐FV model fairly well predicted the sorption amounts of aromatic hydrocarbons, but significantly overestimated those of nonaromatic ones, leading to too small predictions of αS. Pervaporation (PV) behavior of PEO‐PI membranes was governed by sorption behavior followed by membrane swelling. Diffusion coefficient weakly depended on the minimum cross section of a penetrant. The diffusivity selectivity αD hardly depended on the feed composition and was about 1.4 and 0.75 for Bz/Cx and Bz/Hx, respectively. PV selectivity αPV was larger for Bz/Hx than for Bz/Cx because of larger αS. PEO‐PI membranes displayed high specific permeation flux Ql and reasonably high αPV for aromatic/nonaromatic hydrocarbons; for example, Ql = 60 Kg μm/(m2 h) and αPV = 8 for a feed mixture containing Bz, Tol, Hx, n‐Ot and i‐Ot of 20 wt % at 353 K. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 1800–1811, 2000 相似文献
786.
787.
788.
Jae Hee Song Jong Ryoung Park Yeong-Joon Kim 《Colloids and surfaces. A, Physicochemical and engineering aspects》2008,324(1-3):155-158
We describe a synthetic route for the high yield production of Au nanomaterials via a simple one step reduction process. Thenoyltrifluoroacetone was used as a reducing and stabilizing agent as well for the synthesis of gold nanoparticles. The reaction rate for the formation of Au nanoparticles using thenoyltrifluoroacetone was much faster than that of any other β-diketones such as acetylacetone. By simply varying the reaction temperature and the concentration, the shape and size of the resulting Au nanocrystals were easily controlled. The colloidal state of the Au nanocrystals in water lasts several weeks without any spectral changes. 相似文献
789.
Gombojav B Park H Kim JI Ju YS Sung J Cho SI Lee MK Ohrr H Radnaabazar J Seo JS 《Experimental & molecular medicine》2008,40(5):558-564
Elevated heart rate has been proposed as an independent risk factor for cardiovascular diseases, but their interrelationships are not well understood. In this study, we performed a genome-wide linkage scan in 1,026 individuals (mean age 30.6 years, 54.5% women) from 73 extended families of Mongolia and determined quantitative trait loci that influence heart rate. The DNA samples were genotyped using deCODE 1,039 microsatellite markers for 3 cM density genome-wide linkage scan. Correlation analysis was carried out to evaluate the correlation of the covariates and the heart rate. T-tests of the heart rate were also performed on sex, smoking and alcohol intake. Consequently, this model was used in a nonparametric genome-wide linkage analysis using variance component model to create a multipoint logarithm of odds (LOD) score and a corresponding P value. In the adjusted model, the heritability of heart rate was estimated as 0.32 (P<.0001) and a maximum multipoint LOD score of 2.03 was observed in 77 cM region at chromosome 18. The second largest LOD score of 1.52 was seen on chromosome 5 at 216 cM. Genes located on the specified locations in chromosomes 5 and 18 may be involved in the regulation of heart rate. 相似文献
790.
We investigated electronically excited states of caffeine and its 1:1 complex with water by using resonant two-photon ionization (R2PI) and UV-UV hole-burning techniques. Strong vibronic coupling between a pair of close-lying pi-pi* and n-pi* transitions is proposed to be responsible for the broad spectral feature observed. By comparing the experimental results with those of theoretical calculations, both the O-bonded and N-bonded forms were suggested to be initially produced for the 1:1 complex. The electronic transitions of the O-bonded complex were blueshifted in the R2PI spectrum. For the N-bonded complex, the excited state undergoes an ultrafast decay process, followed by dissociation on a repulsive potential energy surface, which gives rise to a characteristically anomalous cluster distribution in nanosecond experiments. 相似文献