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Miao Li Chuanping Feng Zhenya Zhang Zhaoli Shen Norio Sugiura 《Electrochemistry communications》2009,11(10):1853-1856
Electrochemical reduction of nitrate was studied using a Cu/Zn cathode and Ti/Pt, Ti/IrO2–Pt and Ti/RuO2–Pt anodes in an undivided and unbuffered cell. A novel condition for performing both cathodic reduction of nitrate and anodic oxidation of the ammonia and nitrite by-products was achieved using Ti/Pt and Ti/IrO2–Pt anodes in the presence of NaCl, especially with Ti/IrO2–Pt anode. Nitrate could be completely removed using the Ti/IrO2–Pt and Ti/Pt anode, with neither ammonia nor nitrite detected in the treated solution. A low nitrate reduction rate was observed when using a Ti/RuO2–Pt anode in the presence of NaCl. However, in the absence of NaCl, all anodes showed good performance for nitrate reduction, with the Ti/Pt anode having the highest selectivity for reducing nitrate to nitrogen. 相似文献
486.
Ken-Ichi Mitani Kichi-Suke Saito 《Nonlinear Analysis: Theory, Methods & Applications》2009,71(11):310-5247
In [M. Kato and L. Maligranda, On James and Jordan–von Neumann constants of Lorentz sequence spaces, J. Math. Anal. Appl. 258 (2001) 457–465], it is an open problem to compute the James constant of the dual space of two dimensional Lorentz sequence space d(2)(w,q). In this paper, we shall determine the dual norm of d(2)(w,q) and completely compute the James constant of d(2)(w,q). 相似文献
487.
Mori T Kodera T Yoshimine H Kakuta Y Sugiura N Kimata K Okahata Y 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(24):7388-7393
Using a highly sensitive flow-type 27?MHz quartz crystal microbalance, we could detect a small mass change during stepwise and alternating one-sugar transfer of glucuronic acid (GlcA) and N-acetylgalactosamine (GalNAc) to an acceptor, catalyzed by chondroitin polymerase from Escherichia coli strain K4 (K4CP), and analyze the elongation mechanism of K4CP. K4CP was found to bind strongly to a chondroitin acceptor (K(d)=0.97?μM). Although the binding affinity and the catalytic rate constant for each monomer were considerably different, the apparent catalytic efficiency (k(cat)/K(m)) was similar (6.3×10(4) M(-1) s(-1) for GlcA transfer and 3.4×10(4) M(-1) s(-1) for the GalNAc transfer). This is reasonable for the smooth alternating elongation of GlcA and GalNAc on the acceptor. This is the first study to report the determination of kinetic parameters for enzymatic, alternated, sugar elongation. 相似文献
488.
The well-known theorem of Erd?s-Pósa says that a graph G has either k disjoint cycles or a vertex set X of order at most f(k) for some function f such that G\X is a forest. Starting with this result, there are many results concerning packing and covering cycles in graph theory and combinatorial optimization. In this paper, we discuss packing disjoint S-cycles, i.e., cycles that are required to go through a set S of vertices. For this problem, Kakimura-Kawarabayashi-Marx (2011) and Pontecorvi-Wollan (2010) recently showed the Erd?s-Pósa-type result holds. We further try to generalize this result to packing S-cycles of odd length. In contrast to packing S-cycles, the Erd?s-Pósa-type result does not hold for packing odd S-cycles. We then relax packing odd S-cycles to half-integral packing, and show the Erd?s-Pósa-type result for the half-integral packing of odd S-cycles, which is a generalization of Reed (1999) when S=V. That is, we show that given an integer k and a vertex set S, a graph G has either 2k odd S-cycles so that each vertex is in at most two of these cycles, or a vertex set X of order at most f(k) (for some function f) such that G\X has no odd S-cycle. 相似文献
489.
Polymer incarcerated platinum catalysts (PI Pt) were conveniently prepared from PtCl(2)(COD) or H(2)PtCl(6).6H(2)O and styrene copolymers via reduction of the Pt sources with triethylamine, coacervation, and cross-linking. The Pt catalysts have been successfully applied to catalytic hydrogenation including saturation of heterocyclic compounds. 相似文献
490.
[reaction: see text]. Polymer-incarcerated (PI) palladium catalyst was practically prepared from inexpensive Pd(II) salts and a polystyrene-based copolymer under reducing conditions. Remarkable effects of alkali metal salts on the palladium loading were observed. PI Pd thus prepared showed high catalytic activity in Mizoroki-Heck reactions and Suzuki-Miyaura couplings with a range of substrates including an aryl chloride. In all cases, the Pd catalyst was recovered quantitatively without leaching, and reused several times without significant loss of activity. 相似文献