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981.
Alexander Björling Elisabet Ahlberg Juan M. Feliu 《Electrochemistry communications》2010,12(3):359-361
Electrochemical oxygen adsorption/desorption below monolayer level leads to a disordering of platinum single-crystal surfaces vicinal to the (1 1 1) plane. The kinetics can be described by means of a consecutive reaction from (1 1 1)-terrace sites to (1 1 0)-defect sites, in which (1 0 0)-defects act as intermediates. The first oxidation of the electrode reflects independent contributions from terrace and step sites, the latter being structure sensitive. Oxygen adsorption charges amount to a mean value of one electron per step site. 相似文献
982.
Odysseas Paschos Alexander N. Simonov Alesya N. Bobrovskaya Moritz Hantel Matthias Rzepka Petra Dotzauer Anton N. Popov Pavel A. Simonov Valentin N. Parmon Ulrich Stimming 《Electrochemistry communications》2010,12(11):1490-1492
The electrocatalytic activity of bimetallic BiPd catalysts supported on Sibunit carbon towards hydrogen oxidation/evolution reactions (HOR/HER) was studied in a gas diffusion electrode (GDE) setup. Catalysts were synthesized by deposition of Pd on the carbon support, followed by impregnation of Pd/C precursor with Bi(NO3)3 solution and reduction in hydrogen. Transmission electron microscopy and local EDX elemental analysis revealed that BiPd/C catalysts contain bimetallic particles with narrow size distribution with maxima at 3.2–4.1 nm. X-ray diffraction evidenced that bimetallic particles are constituted by Pd–Bi solid solution. It was shown that modification of Pd/C by bismuth increases the specific activity of palladium towards HOR/HER by a factor of 3. 相似文献
983.
Anna K. Renfrew Alexander E. Egger Rosario Scopelliti Christian G. Hartinger Paul J. Dyson 《Comptes Rendus Chimie》2010,13(8-9):1144-1150
Metal complexes bearing phosphine ligands are attracting increasing attention for their applications in medicinal chemistry. In particular, organometallic ruthenium-phosphine complexes have been found to exhibit promising antitumour activity. The synthesis, anticancer activity and reactivity of a novel bis-phosphine complex, [Ru(η6-cymene)(PPh2(o-C6H4O)-κ2-P,O)(pta)]Cl (pta = 1,3,5-triaza-7-phosphatricyclo[3.3.1.1.]decane), is presented. The complex appears to exhibit its anticancer effect via a different mechanism to other ruthenium-arene pta complexes with labile co-ligands. 相似文献
984.
Rasheed AhmadKhera Rasheed Ahmad Ihsan Ullah Obaid‐Ur‐Rahman Abid Olumide Fatunsin Muhammad Sher Alexander Villinger Peter Langer 《Helvetica chimica acta》2010,93(9):1705-1715
2‐Aryl‐2,3‐dihydro‐4H‐pyran‐4‐ones were prepared in one step by cyclocondensation of 1,3‐diketone dianions with aldehydes. The use of HCl (10%) for the aqueous workup proved to be very important to avoid elimination reactions of the 5‐aryl‐5‐hydroxy 1,3‐diones formed as intermediates. The TiCl4‐mediated cyclization of a 2‐aryl‐2,3‐dihydro‐4H‐pyran‐4‐one with 1,3‐silyloxybuta‐1,3‐diene resulted in cleavage of the pyranone moiety and formation of a highly functionalized benzene derivative. 相似文献
985.
Asad Ali Munawar Hussain Imran Malik Alexander Villinger Christine Fischer Peter Langer 《Helvetica chimica acta》2010,93(9):1764-1772
Double Heck cross‐coupling reactions of 2,3‐ and 3,5‐dibromopyridine with various alkenes afforded the corresponding novel di(alkenyl)pyridines. The Heck reaction of 2,5‐dibromopyridine unexpectedly afforded 5,5′‐di(alkenyl)‐2,2′‐bipyridines by palladium‐catalyzed dimerization to give 5,5′‐dibromo‐2,2′‐bipyridine and subsequent twofold Heck reaction. 相似文献
986.
Jürgen Brüning Alexander Peters Jan W. Bats Martin U. Schmidt 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(1):o1-o4
Single crystals of the title compound, C9H10N3O3+·Cl−·H2O, were obtained by recrystallization from hydrochloric acid. The cations stack along the crystallographic a direction. The 2,3‐dioxo‐1,4‐dihydroquinoxaline group shows a significant deviation from planarity [r.m.s. deviation from the best plane = 0.063 (2) Å]. Hydrogen bonding links the cations, chloride anions and water molecules to form an extended three‐dimensional architecture. 相似文献
987.
Ganna A. Senchyk Andrey B. Lysenko Eduard B. Rusanov Alexander N. Chernega Konstantin V. Domasevitch 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(7):m180-m183
In the structures of the CdII pseudohalide coordination polymer poly[[diaquabis[μ2‐3,3′‐bis(1,2,4‐triazol‐4‐yl)‐1,1′‐biadamantane‐κ2N1:N1′]cadmium(II)] dithiocyanate dihydrate], {[Cd(C24H32N6)2(H2O)2](NCS)2·2H2O}n, (I), and the isomorphous selenocyanate analogue, {[Cd(C24H32N6)2(H2O)2](NCSe)2·2H2O}n, (II), the CdII cations occupy inversion centres and have octahedral CdN4O2 environments, completed by four N atoms of the organic ligands [Cd—N = 2.316 (2) and 2.361 (2) Å for (I), and 2.313 (3) and 2.372 (3) Å for (II)] and two trans‐coordinated aqua ligands [Cd—O = 2.3189 (15) Å for (I) and 2.323 (2) Å for (II)]. In each compound, the ligand displays a bidentate N1:N1′‐bridging mode, connecting the metal centres at a distance of 14.66 Å into two‐dimensional nets of (4,4)‐topology, while the uncoordinated thio(seleno)cyanate anions reside inside the net cavities. Hydrogen bonding between the water molecules, anions and 1,2,4‐triazole N atoms supports the tight packing, with an interlayer distance of 6.09 Å. 相似文献
988.
David Aebisher Matibur Zamadar Adaickapillai Mahendran Goutam Ghosh Catherine McEntee Alexander Greer 《Photochemistry and photobiology》2010,86(4):890-894
Traditionally, Type II heterogeneous photo-oxidations produce singlet oxygen via external irradiation of a sensitizer and external supply of ground-state oxygen. A potential improvement is reported here. A hollow-core fiber-optic device was developed with an “internal” supply of light and flowing oxygen, and a porous photosensitizer-end capped configuration. Singlet oxygen was delivered through the fiber tip. The singlet oxygen steady-state concentration in the immediate vicinity of the probe tip was ca 20 f m by N-benzoyl- dl -methionine trapping. The device is portable and the singlet oxygen-generating tip is maneuverable, which opened the door to simple disinfectant studies. Complete Escherichia coli inactivation was observed in 2 h when the singlet oxygen sensitizing probe tip was immersed in 0.1 mL aqueous samples of 0.1–4.4 × 107 cells. Photobleaching of the probe tip occurred after ca 12 h of use, requiring baking and sensitizer reloading steps for reuse. 相似文献
989.
990.