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181.
Extraction studies of uranium(VI) by the binary mixture of PC88A and benzimidazole show an antagonistic behavior in the concentration range 10−5–10−6M of PC88A and 0.005M of benzimidazole. Antagonism is observed due to the deprotonation of PC88A by benzimidazole forming an adduct resulting in the virtual removal of PC88A from the system.  相似文献   
182.
We consider all Test matches played between 1877 and 2010 and One Day International (ODI) matches played between 1971 and 2010. We form directed and weighted networks of teams and also of their captains. The success of a team (or captain) is determined by the ‘quality’ of the wins, not simply by the number of wins. We apply the diffusion-based PageRank algorithm to the networks to assess the importance of the wins, and rank the respective teams and captains. Our analysis identifies Australia as the best team in both forms of cricket, Test and ODI. Steve Waugh is identified as the best captain in Test cricket and Ricky Ponting is the best captain in the ODI format. We also compare our ranking scheme with an existing ranking scheme, the Reliance ICC ranking. Our method does not depend on ‘external’ criteria in the ranking of teams (captains). The purpose of this paper is to introduce a revised ranking of cricket teams and to quantify the success of the captains.  相似文献   
183.
Cetylpyridinium chloride (CPC) inhibits the Cr(VI) oxidation of ethanol and propan-1-ol while sodium dodecyl sulfate (SDS) catalyzes the title reactions. At higher values of the [surfactant], the rate attains a limiting value. The micellar effect has been explained by considering the preferential partitioning of the reactants in terms of the suggested mechanism. Applicability of the Menger-Portnoy model and Piszkiewicz model to explain the observed micellar effect has been examined. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
184.
We define equivariant cyclic and Hochschild cohomology modules of a cyclic objectX in the category ofG-sets and relate them with the Bredon cohomologies of the cyclic geometric realization |X|cy.  相似文献   
185.
Equilibrium study on the mixed ligand complex formation of CuII with biguanide(Bg) and glycine (HG), indicated the formation of the complexes: Cu(Bg)2+, Cu(Bg) 2 2+ , Cu(Bg-H)(Bg)+, Cu(Bg-H)2, Cu(Bg)(OH)+, Cu(Bg-H)(OH); Cu(G)+, Cu(G)(OH), Cu(G)2; Cu(G)(Bg)+, Cu(G)(Bg-H); (G)Cu(Bg)Cu(G)2+, (G)Cu(Bg-H)Cu(G)+, and (G)Cu(Bg-2H)Cu(G). From the deprotonation constants of coordinated biguanide (Bg) in the complexes Cu(Bg)(OH)+, Cu(Bg-H)(Bg)+ and Cu(G)(Bg)+, the Lewis basicities of the coordinated ligand species (Bg-H)-, OH- and glycinate (G-) were found to be of the order: (Bg-H)-≫ OH- > G-. Bridging (N1-N4, N2-N5) tetradentate mode of coordination by biguanide species Bg, (Bg-H)- and (Bg2H)2- was indicated from the occurrence of biguanide-bridged dinuclear mixed ligand complexes (G)Cu(Bg)Cu(G)2+, (G)Cu(Bg-H)Cu(G)+, (G)Cu(Bg-2H)Cu(G) in the complexation equilibria.  相似文献   
186.
This paper presents a translation of a theorem of Cartan into an equivariant setting. This work is largely based on the study of the homotopical algebra in the sense of Quillen of the category of simplicial objects over the category of rationalO g-vector spaces. The application is a solution to the equivariant commutative cochain problem. This solution is slightly better than the solution obtained earlier by Triantafillou in that the transformation groupG need not be finite.  相似文献   
187.
Ab initio calculations have been carried out to study the magnetic dipole and electric quadrupole hyperfine structure constants of 205Pb+. Many-body effects have been considered to all orders using the relativistic coupled-cluster theory in the singles, doubles and partial triples approximation. The trends of these effects are found to be different from atomic systems that have been studied earlier.  相似文献   
188.
Sayak Mukherjee 《Physica A》2007,384(1):80-82
Starting from the well-known field theory for directed percolation (DP), we describe an evolving population, near extinction, in an environment with its own nontrivial spatio-temporal dynamics. Here, we consider the special case where the environment follows a simple relaxational (Model A) dynamics. Two new operators emerge, with upper critical dimension of four, which couple the two theories in a nontrivial way. While the Wilson-Fisher fixed point remains completely unaffected, a mismatch of time scales destabilizes the usual DP fixed point, suggesting a crossover to a first-order transition from the active (surviving) to the inactive (extinct) state.  相似文献   
189.
The synthesis of silicon nanowires that are densely coated with silicon nanoparticles is reported. These structures were produced in a two-step process, using a method known as hypersonic plasma particle deposition. In the first step, a Ti–Si nanoparticle film was deposited. In the second step the Ti-source was switched off, and nanoparticle-coated nanowires grew under the simultaneous action of Si vapor deposition and bombardment by Si nanoparticles. Total process time, including both steps, equaled 5 min, and resulted in formation of a dense network of randomly oriented nanowires covering1.5 cm2 of substrate area. The nanowires are composed of single-crystal Si. The diameters of the nanowires vary over the range 100–800 nm. Each nanowire has a crystalline TiSi2 catalyst particle, believed to have been solid during nanowire growth, at its tip.  相似文献   
190.
We investigate the relation between the local variables of a discrete integrable lattice system and the corresponding separation variables, derived from the associated spectral curve. In particular, we have shown how the inverse transformation from the separation variables to the discrete lattice variables may be factorized as a sequence of canonical transformations.  相似文献   
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