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121.
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123.
The extraction of Co(II) with mixtures of 1-phenyl-3-methyl-4-benzoyl-pyrazol-5-one ((H)PMBP) and tri-n-octylamine (TOA) is investigated in order to explore the influence of diluents and inorganic anions with synergistic acidic extractant + liquid anion exchanger systems. Although it is proved that the same species [HTOA]+ [Co(PMBP)3]? is extracted from various inorganic media, with toluene as the diluent, the presence of ClO4? SO42? or Cl? anion modifies the distribution of the anions which are associated to (HTOA)+ in the organic phase, leading to different synergistic equilibria; with Cl? or SO42?: + ,PMBP?) ?,Co(PMBP)3? (log K = 6.10) and with ClO4? : + + ,ClO4? ? ,Co(PMBP)3? + H+ + ClO4? (log K = 2.34) The same synergistic equilibrium is observed for the extraction of Ni(II) from ClO4? medium, with a comparable value of the constant (log K = 2.45). The synergistic effect is cancelled in n-octanol. 相似文献
124.
J.-M. Andr M. Cl. Andr G. Leroy J. Weiler 《International journal of quantum chemistry》1969,3(6):1013-1025
All-electron SCF –LCAO –MO computations for diazomethane, ketene and allene are presented. The basis functions are contracted Gaussian orbitals. Theoretical results are discussed and related to available experimental data. 相似文献
125.
We present a theoretical study of the propagation of a monochromatic pressure wave in an unbounded monodisperse bubbly liquid.
We begin with the case of a regular bubble array --a bubble crystal-- for which we derive a dispersion relation. In order
to interpret the different branches of this relation, we introduce a formalism, the radiative picture, which is the adaptation
to acoustics of the standard splitting of the electric field in an electrostatic and a radiative part in Coulomb gauge. In
the case of an irregular or completely random array --a bubble glass-- and at wavelengths large compared to the size of the
bubble array spatial inhomogeneities, the difference between order and disorder is not felt by the pressure wave: a dispersion
relation still holds, coinciding with that of a bubble crystal with the same bubble size and air volume fraction at the centre
of its first Brillouin zone. This relation is discussed and compared to that obtained by Foldy in the framework of his multiscattering
approach. 相似文献
126.
Dedryvère R Leroy S Martinez H Blanchard F Lemordant D Gonbeau D 《The journal of physical chemistry. B》2006,110(26):12986-12992
X-ray photoelectron valence spectra of lithium salts LiBF4, LiPF6, LiTFSI, and LiBETI have been recorded and analyzed by means of density functional theory (DFT) calculations, with good agreement between experimental and calculated spectra. The results of this study are used to characterize electrode/electrolyte interfaces of graphite negative electrodes in Li-ion batteries using organic carbonate electrolytes containing LiTFSI or LiBETI salts. By a combined X-ray photoelectron spectroscopy (XPS) core peaks/valence analysis, we identify the main constituents of the interface. Differences in the surface layers' composition can be evidenced, depending on whether LiTFSI or LiBETI is used as the lithium salt. 相似文献
127.
128.
We introduce the notion of predicted decrease approximation (PDA) for constrained convex optimization, a flexible framework which includes as special cases known algorithms such as generalized conditional gradient, proximal gradient, greedy coordinate descent for separable constraints and working set methods for linear equality constraints with bounds. The new scheme allows the development of a unified convergence analysis for these methods. We further consider a partially strongly convex nonsmooth model and show that dual application of PDA-based methods yields new sublinear convergence rate estimates in terms of both primal and dual objectives. As an example of an application, we provide an explicit working set selection rule for SMO-type methods for training the support vector machine with an improved primal convergence analysis. 相似文献
129.
130.
O. Bajeat N. Lecesne R. Leroy L. Maunoury B. Osmond M. Sjodin A. Maitre N. Pradeilles 《Hyperfine Interactions》2013,216(1-3):115-119
SPIRAL2 is the new project under construction at GANIL to provide radioactive ion beams to the Nuclear Physics Community and in particular neutron rich ion beams. For the production of condensable radioactive elements, a resonant ionization laser ion source is under development at GANIL. In order to generate the ions of interest with a good selectivity and purity, our group is studying the way to minimize surface ionization process by using refractory materials with low work function as ionizer tube. To do those investigations a dedicated ion source, called SOMEIL (Source Optimisée pour les Mesures d‘Efficacité d‘Ionisation Laser) is used. Numerous types of ionizer tubes made in various materials and geometry are tested. Surface ionization and laser ionization efficiencies can be measured for each of them. 相似文献