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61.
62.
The thermal decomposition studies for two palladium(II) complexes Pd(apyr)2Cl2 and Pd(pmpa)Cl2 (apyr=1–aminopyrene and pmpa=N–(2–pyridylmethylene)–1–pyrenylamine) were carried out in pure nitrogen using TG-DTG techniques. The non-isothermal kinetic parameters for the two complexes were evaluated employing the method suggested by Málek, esták, Koga et al. Based on the above results, thermal behaviour of the complexes were carefully discussed, which showed that not only the parameters value, but also the decomposition pattern and mechanism for complex 1 are different from complex 2.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
63.
Ceramic BaCe0.8Ho0.2O3-α with orthorhombic perovskite structure was prepared by conventional solid state reaction, and its conductivity and ionic transport number were measured by ac impedance spectroscopy and gas concentration cell methods in the temperature range of 600-1000 ℃ in wet hydrogen and wet air, respectively. Using the ceramics as solid electrolyte and porous platinum as electrodes, the hydrogen-air fuel cell was constructed, and the cell performance at temperature from 600-1000 ℃ was examined. The results indicate that the specimen was a pure protonic conductor with the protonic transport number of 1 at temperature from 600-900 ℃ in wet hydrogen, a mixed conductor of proton and electron with the protonic transport number of 0.99 at 1000 ℃. The electronic conduction could be neglected in this case, thus the total conductivity in wet hydrogen was approximately regarded as protonic conductivity. In wet air, the specimen was a mixed conductor of proton, oxide ion and electron hole. The protonic transport numbers were 0.01-0.09, and the oxide-ionic transport numbers were 0.27-0.32. The oxide ionic conductivity was increased with the increase of temperature, but the protonic conductivity displayed a maximum at 900 ℃, due to the combined increase in mobility and depletion of the carriers. The fuel cell could work stably. At 1000 ℃, the maximum short-circuit current density and power output density were 346 mA/cm^2 and 80 mW/cm^2, respectively. 相似文献
64.
A very simple, selective and sensitive method was developed for the spectrophotometric determination of Mo in the presence of W. The method was based on the formation of color charge transfer complex, molybdotungstophosphate-3,3',5,5'-tetramethylbezidine anion, which was solubilized and stabilized in PVA medium. Following the recommended procedure, molybdenum could be determined in the linear range of 0.04-2.5 mug ml(-1) and the molar absorptivity was 1.47x10(4) l mol(-1) cm(-1) at 660 nm. The proposed method had been applied to the determination of trace molybdenum in tungsten ore with satisfactory results. 相似文献
65.
Assembly of a supramolecular cube, [(Cp*WS3Cu3)8 Cl8(CN)12Li4] from a preformed incomplete cubane-like compound [PPh4][Cp*WS3(CuCN)3 总被引:2,自引:0,他引:2
Lang JP Xu QF Chen ZN Abrahams BF 《Journal of the American Chemical Society》2003,125(42):12682-12683
A supramolecular cube has been formed by linking WS3Cu3 clusters with bidentate ligands. Eight WS3Cu3 clusters, which have an incomplete cubane-like structure, serve as the three connecting nodes of the cube, while 12 bridging cyanide anions coordinated to copper centers lie along the edges of the cube. Eight chloride anions and four lithium cations are located inside the cube. 相似文献
66.
67.
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
68.
C.Akira Horiuchi Akinori Takeda Wen Chai Kishoh Ohwada Shun-Jun Ji T.Tomoyoshi Takahashi 《Tetrahedron letters》2003,44(52):9307-9311
A novel reaction of α-iodo ketone (α-iodocycloalkanone, α-iodo-β-alkoxy ester, and α-iodoacyclicketone) with irradiation under a high-pressure mercury lamp gave the corresponding α-hydroxyketone in good yields. In the case of α,α′-diiodo ketone, α,α′-dihydroxyketone which little has been reported until now was obtained. This reaction affords a new, clean and convenient synthetic method for α-hydroxy- and α,α′-dihydroxyketone. 相似文献
69.
HUA Guo-Pinga ZHU Xiao-Tongb ZHANG Jin-Pengb XU Jia-Ningb WANG Qianb JI Shun-Junc ZHANG Yongc TU Shu-Jiangb② a 《结构化学》2006,25(5):599-603
1 INTRODUCTION Various quinolone derivatives are known to dis- play interesting biological properties ranging from microbial activity to cytotoxicity[1]. They have been reported as antiviral (HIV-1)[2] and antitumor agents[3] as well as used as tubulin[4], topoisomerase[5] and thrombocyte inhibitors[6]. As a member of the quino- lone family, substituted N-phenyl-2-quinolones re-present the structural basis of many biologically active compounds, such as protein kinase inhibitors, immunodu… 相似文献
70.
Yuliang Jiang Sheng Zhang Bingxiang Wang Tao Qian Can Jin Shishan Wu Jian Shen 《Tetrahedron》2018,74(39):5733-5738
Hypochlorite (OCl?) plays important roles both in physiological and pathological processes, the detection of which is of great significance. Herein, a novel fluorescent probe based on the triphenylamine-type schiff base derivative (TPAD) was developed to detect OCl?. Probe TPAD exhibited specific fluorescence response toward ClO? with the fluorescence quenching rate up to 80%, and the detection limit was estimated to be 0.8?μM. The sensing mechanism study demonstrated that TPAD reacted with ClO?via an oxidation process, which was evidenced by MS and NMR characterization. Moreover, owing to the excellent sensing properties and negligible cytotoxicity, TPAD was successfully applied in the bioimaging of OCl? in living A549?cells. 相似文献