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21.
A series of cyano-bridged binuclear mixed valence complexes of the general formula M-Ru(III)(NH(3))(4)pyCOOH [pyCOOH = isonicotinic acid; M = cis-Ru(bpy)(2)(CN)(2), 1 (bpy = 2,2' bipyridine); trans-Ru(py)(4)(CN)(2), 2 (py = pyridine); [Ru(CN)(6)](4)(-), 3; [Fe(CN)(6)](4)(-), 4] have been prepared and anchored through the carboxylic function to nanocrystalline TiO(2) or SnO(2) electrodes. The complexes display a reversible electrochromic behavior in the range of applied potential from -0.5 to +0.5 V, versus SCE. Tuning of the electronic transitions in the visible and near-infrared spectral regions is achieved through changes of the solvent and of the cyano-bridged metal moiety M. 相似文献
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Even-numbered 1-alkanols from butanol to tetradecanol were evaluated for solubilizing and microemulsifying methanol in triolein and for their effectiveness on water tolerances of the hybrid fuels. Photon correlation spectroscopy determinations indicated molecular dispersions formed rather than nonaqueous microemulsions, but the addition of water to the solubilized systems did produce certain quarternary compositions that exhibited microemulsion properties. 1-Octanol imparted optimal, whereas 1-butanol and 1-tetradecanol imparted minimal, water tolerance for the hybrid fuels. Among four isomeric octanols studied, the 1- and 4-octanols were superior to the 2- and 3-octanols for water tolerance. This superiority is attributed to stronger hydrogen bonding and greater association in the 1-and 4-isomers compared to the 2- and 3-isomers. 相似文献
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Human Y‐chromosome SNP characterization by multiplex amplified product‐length polymorphism analysis 下载免费PDF全文
Laura Smeldy Jurado Medina Marina Muzzio Marisol Schwab María Leticia Bravi Costantino Guillermo Barreto Graciela Bailliet 《Electrophoresis》2014,35(17):2524-2527
We designed an allele‐specific amplification protocol to optimize Y‐chromosome SNP typing, which is an unavoidable step for defining the phylogenetic status of paternal lineages. It allows the simultaneous highly specific definition of up to six mutations in a single reaction by amplification fragment length polymorphism (AFLP) without the need of specialized equipment, at a considerably lower cost than that based on single‐base primer extension (SNaPshot?) technology or PCR‐RFLP systems, requiring as little as 0.5 ng DNA and compatible with the small fragments characteristic of low‐quality DNA. By designation of two primers recognizing the derived and ancestral state for each SNP, which can be differentiated by size by the addition of a noncomplementary nucleotide tail, we could define major Y clades E, F, K, R, Q, and subhaplogroups R1, R1a, R1b, R1b1b, R1b1c, J1, J2, G1, G2, I1, Q1a3, and Q1a3a1 through amplification fragments that ranged between 60 and 158bp. 相似文献
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Summary. The Galerkin discretization of a Fredholm integral equation of the second kind on a closed, piecewise analytic surface is analyzed. High order, -boundary elements on grids which are geometrically graded toward the edges and vertices of the surface give exponential convergence,
similar to what is known in the -Finite Element Method. A quadrature strategy is developed which gives rise to a fully discrete scheme preserving the exponential
convergence of the -Boundary Element Method. The total work necessary for the consistent quadratures is shown to grow algebraically with the
number of degrees of freedom. Numerical results on a curved polyhedron show exponential convergence with respect to the number
of degrees of freedom as well as with respect to the CPU-time.
Received April 22, 1996 相似文献
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Convergence rates for sparse chaos approximations of elliptic problems with stochastic coefficients 总被引:2,自引:0,他引:2
** Email: todor{at}math.ethz.ch*** Corresponding author. Email: schwab{at}math.ethz.ch A scalar, elliptic boundary-value problem in divergence formwith stochastic diffusion coefficient a(x, ) in a bounded domainD d is reformulated as a deterministic, infinite-dimensional,parametric problem by separation of deterministic (x D) andstochastic ( ) variables in a(x, ) via KarhúnenLoèveor Legendre expansions of the diffusion coefficient. Deterministic,approximate solvers are obtained by projection of this probleminto a product probability space of finite dimension M and sparsediscretizations of the resulting M-dimensional parametric problem.Both Galerkin and collocation approximations are considered.Under regularity assumptions on the fluctuation of a(x, ) inthe deterministic variable x, the convergence rate of the deterministicsolution algorithm is analysed in terms of the number N of deterministicproblems to be solved as both the chaos dimension M and themultiresolution level of the sparse discretization resp. thepolynomial degree of the chaos expansion increase simultaneously. 相似文献
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We analyze the quantum dynamics of a micromechanical resonator capacitively coupled to a Cooper-pair box. With appropriate quantum state control of the Cooper box, the resonator can be driven into a superposition of spatially separated states. The Cooper box can also be used to probe the decay of the resonator superposition state due to environmental decoherence. 相似文献