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991.
Chun Li 《Tetrahedron》2004,60(37):8037-8041
It has been confirmed that octasulfonatocalix[8]arene (Calx-S8) and tris(2,2′-bipyridine)ruthenium (II) (Ru(bpy)32+) can form a stable host-guest complex in aqueous solution. The binding constant for 1:1 [Calx-S88−·Ru(bpy)32+]6− complex formation was estimated to be (2.4±0.8)×104 dm3 mol−1 by fluorescence titration, which indicates that the [Calx-S88−·Ru(bpy)32+]6− complex is the main species in 1:1 molar ratio aqueous solution of Calx-S8 and Ru(bpy)32+. In situ UV-Vis spectroscopic measurements indicated that Ru(bpy)32+ complexes can be readily deposited onto ITO electrode through electrochemical polymerization of 3,4-ethylenedioxythiophene (EDOT) using [Calx-S88−·Ru(bpy)32+]6− host-guest complex as a dopant anion owing to the electrostatic interaction between the cationic conductive polymer and the anionic host-guest complex. The loading degree of the composite film with Ru(bpy)32+ can be determined by Lambert-Beer law modified for the two-dimensional concentration. The obtained composite film showed good photoelectric conversion properties in response to visible light irradiation. This is a novel photocurrent generation system in which the photoexcited state energy is efficiently collected by the conductive polymeric layer. 相似文献
992.
采用非晶态多核配合的方法合成了La1-xCuxMnO3(x=0、0.05、0.1、0.2、0.3、0.4、0.5)系列催化剂, 并用X射线衍射(XRD)、透射电镜(TEM)、比表面测定仪(BET)等手段对催化剂的微观结构进行了表征. 研究了Cu掺杂对钙钛矿结构及其对CO催化氧化发光性能及催化氧化CO、CH4性能的影响规律. 结果表明, 当x≤0.1 时, Cu掺杂仍可形成单相的钙钛矿结构; 当x>0.1时, 过量掺杂的Cu以CuO杂相存在. Cu掺杂可改善La1-xCuxMnO3催化剂对CO和CH4的催化氧化活性. 经700 ℃焙烧3 h制备的La0.9Cu0.1MnO3催化剂具有最高CO催化氧化活性(T100%=170 ℃), 该结果与CO催化氧化发光结果一致.而La0.95Cu0.05MnO3催化剂对CH4的催化氧化活性最高(T95%=705 ℃). 相似文献
993.
I. V. Ukrainets E. V. Mospanova L. V. Sidorenko 《Chemistry of Heterocyclic Compounds》2007,43(7):863-870
An improved method is reported for the synthesis of a series of 1-hydroxy-3-oxo-5,6-dihydro-3H-pyrrolo[3,2,1-ij]quinoline-2-carboxylic
acid hetarylamides. The antitubercular activity of all of the compounds prepared has been studied. The structure-biological
activity dependence revealed is discussed.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 1023–1033, July, 2007. 相似文献
994.
G. Kumaraswamy A. Pitchaiah G. Ramakrishna D.S. Ramakrishna K. Sadaiah 《Tetrahedron letters》2006,47(12):2013-2015
An efficient protocol for the benzylation or allylation of amides using the corresponding benzyl or allyl chlorides as electrophiles under basic conditions with commercially available 5 mol % of [Cu(OH)TMEDA]2Cl2 as catalyst was developed. Under these conditions, unprotected amino acids were benzylated without any racemization. 相似文献
995.
A new ion-pair complex, [1-(4′-chlorobenzyl)-4-aminopyridinium](+)bis(maleonitrile-dithiolato)nickel(−),[ClbzPyNH2][Ni(mnt)2] (1), has been prepared and characterized. X-ray single crystal structure conforms that the Ni(mnt)2− anions and [ClbzPyNH2]+ cations of 1 form completely segregated uniform stacking columns with the Ni?Ni distance 3.944 Å in the Ni(mnt)2− stacking column. The temperature dependence of the magnetic susceptibility reveals that 1 undergoes a magnetic transition, and exhibits ferromagnetic interaction in the high-temperature phase and spin gap system in the low-temperature phase. 相似文献
996.
298.15K下Li2B4O7-H2O体系水蒸汽分压及渗透系数的等压测定和离子相互作用模型 总被引:2,自引:0,他引:2
在已有研究含硼体系的文献中仅考虑了硼酸根B4O7^-2或B(OH)4^-和H3BO3的存在,而对Li2B4O7-H2O体系具有多种硼物种聚合平衡体系的热力学性质的研究尚未见报道.本文用等压法研究了Li2B4O7-H2O体系于298.15K下浓度由稀到过饱和溶液的平衡气相蒸汽压及渗透系数.考虑了水溶液中多种硼物种的存在,以Pitzer方程为基础,建立了可描述该含硼体系的离子相互作用模型。 相似文献
997.
Catalytic Enantioselective Reduction of Prochiral Ketones with Chiral Ferrocenyl Amino Alcohols 总被引:1,自引:0,他引:1
The asymmetric reduction of prochiral ketones was catalyzed by a class of recoverable and highly stable chiral ferrocenyl amino alcohols derived from natural amino acids to yield optically active secondary alcohols in high chemical yields and moderate to good enantiomeric excesses. 相似文献
998.
Malose J. Mphahlele Ahmed M. El-Nahas Tarek M. El-Gogary 《Journal of Molecular Structure》2004,690(1-3):151-157
The geometries of the title compounds were probed in solution, solid and gas states using spectroscopic methods, X-ray crystallography and quantum chemical techniques. The exclusive existence of the NH-4-thiones in solution (NMR and PCM-B3LYP(MP2)/6-31+G(d) calculations) and solid state (FT-IR and X-ray) is also corroborated by comparison of their spectroscopic data with those of the corresponding 2-aryl-1-methylquinoline-4(1H)-thione derivatives. The co-existence of the quinoline-4-thione and quinoline-4-thiol (4-mercaptoquinoline) isomers in the gas phase is confirmed by mass spectrometry and the preponderance of the 4-thiol is supported by quantum chemical techniques (PM3, MP2 and B3LYP). 相似文献
999.
Dhanpat Rai Yuanxian Xia Linfeng Rao Nancy J. Hess Andrew R. Felmy Dean A. Moore David E. McCready 《Journal of solution chemistry》2005,34(4):469-498
The objectives of this study were to address uncertainties in the solubility product of (UO2)3(PO4)2⋅4H2O(c) and in the phosphate complexes of U(VI), and more importantly to develop needed thermodynamic data for the Pu(VI)-phosphate system in order to ascertain the extent to which U(VI) and Pu(VI) behave in an analogous fashion. Thus studies were conducted on (UO2)3(PO4)2⋅4H2O(c) and (PuO2)3(PO4)2⋅4H2O(am) solubilities for long-equilibration periods (up to 870 days) in a wide range of pH values (2.5 to 10.5) at fixed phosphate concentrations of 0.001 and 0.01 M, and in a range of phosphate concentrations (0.0001–1.0 M) at fixed pH values of about 3.5. A combination of techniques (XRD, DTA/TG, XAS, and thermodynamic analyses) was used to characterize the reaction products. The U(VI)-phosphate data for the most part agree closely with thermodynamic data presented in Guillaumont et al.,(1) although we cannot verify the existence of several U(VI) hydrolyses and phosphate species and we find the reported value for formation constant of UO2PO−4 is in error by more than two orders of magnitude. A comprehensive thermodynamic model for (PuO2)3(PO4)2⋅4H2O(am) solubility in the H+-Na+-OH−-Cl−-H2PO−4-HPO2−4-PO3−4-H2O system, previously unavailable, is presented and the data shows that the U(VI)-phosphate system is an excellent analog for the Pu(VI)-phosphate system. 相似文献
1000.
L. I. Belen’kii A. V. Kolotaev V. Z. Shirinyan M. M. Krayushkin Yu. P. Strokach T. M. Valova Z. O. Golotyuk V. A. Barachevskii 《Chemistry of Heterocyclic Compounds》2005,41(1):86-92
The polar [4+2] cycloaddition reaction of 1,2-bis(2,5-dimethyl-3-thienyl)acetylene with thiobenzamide and certain aldehydes of the thiophene and furan series catalyzed by boron trifluoride etherate gives the corresponding 4-hetaryl-5,6-di(2,5-dimethyl-3-thienyl)-2-phenyl-4H-1,3-thiazines. The photochromic properties of the products have been studied.__________Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 100–106, January, 2005. 相似文献