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131.
A novel inorganic-organic hybrid compound, {[Co(dien)]4[0aO4)MoV8(wV10.56MoV10.44)4- O33(OH)3]}'nH20 (1, n = 1, dien = diethylenetriamine), has been synthesized hydrothermally and characterized by single-crystal X-ray diffraction. Compound 1 crystallizes in the triclinic system with a = 11.927(2), b = 13.328(3), c = 19.306(4)A, a = 93.76(3), β = 94.14(3), γ = 109.99(3)°, V= 2863.2(12) A3, space group P1 and Z = 2 at 173 K. The final full-matrix least-squares refinement converged to R = 0.049 for 9621 observed reflections with 1 〉 2σ(I) and wR = 0.139 for all data (9871) and S = 1.073. Crystal structure analysis shows that 1 contains a kind of the first reported mixed-valence and molybdenum-tungsten mixed-distributed e-Keggin structural polyanion capped by four Co(dien) fragments with the main group element P occupying the center site. These results were further confirmed by energy-dispersive X-ray spectroscopy (EDS), X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, Thermogravimetry (TG) and X-ray photoelectron spectroscopy (XPS) analyses. 相似文献
132.
Xiao‐Lan Wei Rong Han Xiao Hu Li‐Hui Quan Chun‐Yu Liu Qi Chang Yong‐Hong Liao 《Biomedical chromatography : BMC》2013,27(5):636-640
Six esterase inhibitors, namely EDTA·2Na+, NaF, phenylmethanesulfonyl fluoride, dichlorvos, bis‐nitrophenyl phosphate (BNPP) and thenoyltrifluoroacetone, and the mixture of NaF and BNPP, were evaluated for the stabilization of labile benzoate containing zeylenone in rat plasma. The mixture appeared to exhibit the most effectively stabilizing effect with the degraded content of zeylenone decreasing from >60% (in the absence of inhibitors) to <6%. Following the stabilization by the addition of NaF (5 mm ) and BNPP (5 mm ), the analytes in rat plasma were acidified by formic acid and extracted into ethyl acetate at 0°C. After chromatographic separation, the detection of zeylenone was performed on a 3200 Q‐Trap with positive ion electrospray mode, monitoring the ion transition m/z 383.2 → 105.0. The method was validated over the range from 2.68 to 1340 ng/mL with inter‐ and intra‐run precision for the quality control samples being less than 6.8%. The assay accuracy was within 100 ± 7.0%. The validated method was successfully applied to a pharmacokinetic study in rats after the intratracheal administration of zeylenone in free drug or polymeric micellar solutions. The results showed that the pulmonary absorption of zeylenone loaded in micelles was significantly retarded compared with that of free drug solutions. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
133.
O. M. Hemeda M. A. Henaish S. A. Olofa B. Y. Baradie A. Tawfik 《Journal of Thermal Analysis and Calorimetry》1992,38(10):2291-2299
Sodium acetylacetonate was prepared by the interaction of acetyl acetone with sodium hydroxide. The thermal conductivity, phonon velocity, mean free path, Yong's modulus, and the thermal expansion coefficient were studied. The thermal conductivity of the material decreases with increasing temperature due to the thermal lattice scattering of phonons. The velocity of phonons is also decreased due to the perturbation of thermal phonons. The linear thermal expansion coefficient increases with temperature due to the weakness of the attractive forces between the small Na+ cations and bulkier acetylacetonate anions in the lattice.
Zusammenfassung Natriumacetylacetonat wurde durch die Wechselwirkung zwischen Acetylaceton und Natriumhydroxid gewonnen. Es wurde die Wärmeleitfähigkeit, die Phononengeschwindigkeit, die mittlere freie Wegstrecke, das Elastizitätsmodul und der Wärmeausdehnungskoeffizient untersucht. Die Wärmeleitfähigkeit der Substanz nimmt wegen der thermischen Gitterstreuung der Phononen mit steigender Temparatur ab. Die Geschwindigkeit der Phononen nimmt auf Grund der Perturbierung der thermischen Phononen ebenfalls ab. Der lineare Wärmeausdehnungskoeffizient steigt mit zunehmender Temperatur an, was auf die schwachen Anziehungskräfte zwischen den kleinen Na+ Ionen und den massigen Acetylacetonat-Anionen im Gitter zurückzuführen ist.相似文献
134.
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136.
用L-B膜方法在SnO2电极上修饰了不同链长烷氧基取代的酞菁锌化合物(ZnPc CnH2n+1,n=3,9,12,16),分别研究了它们单分子膜成膜性能和转移性能,并测定了修饰在SnO2电极上的单多层分子膜的光电性能和吸收光谱。研究结果指出链短的取代基即异丙氧基取代的酞菁锌(ZnPcC3H7(i))具有较高的转移比及较好的光电性能。 相似文献
137.
本工作合成了数种带不同取代苯基的羟基喹啉偶氮类化合物。对它们在不同溶剂。不同酸碱度溶液中的偶氮式及腙式间互变异构平衡进行了研究。苯环上不同取代基的引入可引起平衡发生变化。拉电子基的引入有利于腙式结构的形成,而推电子基的引入则对偶氮的生成影响不大。此外,工作中还发现:羟基喹啉偶氮化合物在光照下存在着以偶氮顺-反异构化反应为主的变化过程。 相似文献
138.
A two-dimensional (2D) 3,3,3,4,5,5,6-connected ZnⅡ coordination compound [Zn5(L)2(OH)6]∞ (L=9,10-dioxo-9,10-dihydroanthracene-1,8-dicarboxylate) has been synthesized and characterized by IR, elemental analysis, X-ray powder diffraction and single crystal X-ray diffraction analysis. Moreover, the luminescent properties of the ligand and corresponding compound have been briefly investigated. 相似文献
139.
一种新型黄色荧光类水滑石材料的制备及表征 总被引:1,自引:0,他引:1
用适量的Zn(Ⅱ)取代镁铝水滑石中的Mg(Ⅱ),同时将一定量的2-对联苯基-8-羟基喹啉分散到类水滑石层间的亲油性阴离子中,使其与层板表面上的Zn(Ⅱ)配位,用一步法合成、组装得到一类新型黄色荧光类水滑石复合物(Zn-(HQ-4-biPh)-HTlc)。采用荧光光谱、红外光谱、X射线衍射、扫描电子显微镜和热分析等对其进行了表征。研究结果表明,Zn-(HQ-4-biPh)-HTlc在蓝光(481 nm)激发下可发出黄色荧光(554 nm),与其相应的含锌配合物(Zn[2-(p-biph)-8-Q-O]2)相比,不仅可节省配体用量,而且具有更高的发光强度和更好的热稳定性,有望在白光LED等光电领域得到应用。 相似文献
140.
M. R. Caira A. Coetzee L. R. Nassimbeni E. Weber A. Wierig 《Supramolecular chemistry》2013,25(4):235-241
Abstract This study dealt mainly with the structure-reactivity relationship of selected organic inclusion compounds. The crystal structures of the inclusion compounds of three related hosts, 2,2′–bis(2,7–di-tert-butyl-9–hydroxy-9–fluorenyl)biphenyl, 2,2′–bis (2,7–dichloro-9–hydroxy-9–fluoienyl)biphenyl and 2, 2′–bis(2,7-dibromo-9–hydroxy-9–fluorenyl)biphenyl with 1,4–dioxane (Compound 1), 1,3–dioxane (Compound 2) and 1,3–dioxolane (Compound 3) respectively were elucidated, using single crystal X-ray crystallography. It was found that the guests were either located in channels or constricted channels (cavities), formed by the host framework. The kinetics of desolvation of these compounds were studied and their activation energies were compared. 相似文献