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Thomas W. Bell Albert Firestone Frieda Guzzo Lain-Yen Hu 《Journal of inclusion phenomena and macrocyclic chemistry》1987,5(2):149-152
A series of macrocyclic ligands related to hexaaza[18]-annulene form stable complexes with alkali metal and alkaline earth ions. A planar, substituent-solubilized torand, consisting of multiply fused pyridine rings, has been synthesized and has been found to sequester calcium from a dilute source. 相似文献
13.
Highly effective direct synthesis of DMC from CH_3OH and CO_2 using novel Cu-Ni/C bimetallic composite catalysts 总被引:1,自引:0,他引:1
Novel Cu-Ni/C has been prepared and utilized as an efficient catalyst system in direct synthesis of DMC from CH3OH and CO2. 相似文献
14.
Poly(trimethylene terephthalate)(PTT) is an excellent fiber material.Its thermal degradation and isothermal crystalline behaviors were in this study investigated using thermogravimetric analysis(TGA),thermogravimetric analysis-Fourier transform infrared spectroscopy(TGA-FTIR) analysis,differential scanning calorimetry(DSC) and X-ray diffraction(XRD).The thermal degradation mechanism of PTT follows Mclafferty rearrangement principle.The PTTwithintrinsicviscosity(Ⅳ) of 0.74 dL/g has a maximum crystallinity... 相似文献
15.
Zhong Lv Zhang Zhi Jie Sun Fei Xue Xian Jin Luo Nai Yun Xiu Li Teng Zong Gen Peng 《中国化学快报》2009,20(8):921-923
A series of novel benzimidazole derivatives was synthesized and their anti-Coxsackie virus B_3(CVB_3) activity was evaluated in VERO cells.Compounds 9 and 10 exhibited better inhibitory activity than those of ribavirin(RBV) with IC_(50) values of 5.30 and 1.06μg/mL,respectively. 相似文献
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PEG-400 as an efficient reaction medium for the synthesis of 2,4,5-triaryl-1H-imidazoles and 1,2,4,5-tetraaryl-1H-imidazoles 总被引:1,自引:0,他引:1
An efficient protocol for the one-pot multicomponent synthesis of various 2,4,5-triaryl- IH-imidazoles and 1,2,4,5-tetraaryl-1H-imidazoles using PEG-400 as reaction medium is described. This method has the advantages of good yields, less pollution and simple reaction conditions. 相似文献
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Guzzo MR Uemi M Donate PM Nikolaou S Machado AE Okano LT 《The journal of physical chemistry. A》2006,110(36):10545-10551
In this work, the interaction between fisetin (3,3',4',7-tetrahydroxyflavone) (Fis) and cyclodextrins (CDs) (alpha and beta) was studied through UV-vis absorption, steady-state fluorescence, induced circular dichroism, and (1)H NMR experiments with dependence on temperature and pH. Some experimental data were compared with quantum-mechanics studies based on the SAM1 (AMPAC) semiempirical model, as well as with the B3LYP and MPW1PW91 functional models from density functional theory using the 6-311G and 3-21G basis sets. The spectroscopic measurements show that Fis does not form stable complexes with alpha-CD. On the other hand, at pH 4.0 and 6.5, the complex Fis-beta-CD is formed in a Fis:beta-CD 1:1 stoichiometry and an equilibrium constant (K) of 900 +/- 100 M(-1). In basic medium (pH 11.5), K decreases to 240 +/- 90 M(-1) because Fis deprotonation leads to its better solubilization in water. Molecular modeling points out that Fis is not totally inserted into the inner cavity of beta-CD. The formation of the inclusion complex renders an environment that enhances intramolecular excited state proton transfer. The inclusion complex is formed preferentially via entry of the Fis phenyl group into beta-CD. 相似文献
20.
Shape identities are certain multilinear nonassociative polynomials. In this paper we derive some properties of train algebras of rank 3 which satisfy some shape identity of degree at most 5. 相似文献