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11.
Summary
Applications of Catalytic Reactions. Kinetic Microdetermination of W(VI) and V(V)
A kinetic method is described for the microdetermination of tungsten and vanadium. The method is based on the catalytic action of tungstate and vanadate ions on the oxidation of 2,4-diaminophenol with hydrogen peroxide. The effect of reagent concentration is studied and the maximum tolerable amounts of interfering ions are determined. Procedures for the determination of 0.46 to 73.5g/ml tungsten are given with a relative error of about 1.5%. Quantities of 2.02·10–2 to 2.5g/ml vanadium could be determined with a relative error of about 2%.Furthermore a kinetic determination of tungstate and vanadate ions in their mixtures is proposed.Part of PhD Thesis-University of Thessaloniki, 1975. 相似文献
12.
Under high pressure conditions, cycloheptatriene reacts with methyl propiolate to afford mono-, bis- and trisadducts all retaining, the norcaradiene structure. The four new compounds are formed via [4+21] and [2+2+2] cycloadditions. The latter are examples for the high pressure extension of the scope of homo-Diels-Alder reactions. 相似文献
13.
By showing that the imaginary part of a suitable QCD amplitude, after extrapolation up to the cut, exhibits indeed a prominent bump structure where the -resonance is expected to be, a rather direct indication for the generation of the -resonance by QCD is given. This is achieved by using a mathematically rigorous method of stable analytic extrapolation, based on the theory of maximally converging sequences of polynomials and the application of conformal mappings.Supported in part by BMFT contract 06 MZ 758 and by the PROCOPE program 相似文献
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Angappa Gunasekaran Zahir Irani Thanos Papadopoulos 《The Journal of the Operational Research Society》2014,65(6):806-823
Sustainable operations management (SOM) can be defined as the operations strategies, tactics and techniques, and operational policies to support both economic and environmental objectives and goals. The subject of sustainability has gained much attention from both researchers and practitioners in the past 6–8 years. Most of the articles deal with sustainability from environmental perspectives, but a limited number of them integrate both economic and environmental implications or focus on trading-off between profitability, competitiveness and environmental dimensions. Moreover, there is a limited focus on modelling and analysis (MA) of SOM integrating and balancing the interests of both economic and environmental interests. Therefore, an attempt has been made in this paper to review the extant literature on SOM. The objective is to understand the definition of SOM and present the current status of research in MA, as well as future research directions in the field. Considering the recent focus of the subject, we review the literature on MA of SOM beginning in 2000 in order to make our study current and more relevant for both researchers and practitioners. Finally, a summary of findings and conclusions is reported. 相似文献
19.
E. N. Argyres C. G. Papadopoulos M. T. M. van Kessel R. H. P. Kleiss 《The European Physical Journal C - Particles and Fields》2009,61(3):495-518
We show how to transform a d-dimensional Euclidean path integral in terms of two (Cartesian) fields to a path integral in terms of polar field variables.
First we present a conjecture that states how this transformation should be done. Then we show that this conjecture is correct
in the case of two toy models. Finally the conjecture will be proven for a general QFT model with two fields. 相似文献
20.
Ireneusz W. Bulik Robert Zaleśny Wojciech Bartkowiak Josep M. Luis Bernard Kirtman Gustavo E. Scuseria Aggelos Avramopoulos Heribert Reis Manthos G. Papadopoulos 《Journal of computational chemistry》2013,34(20):1775-1784
A set of exchange‐correlation functionals, including BLYP, PBE0, B3LYP, BHandHLYP, CAM‐B3LYP, LC‐BLYP, and HSE, has been used to determine static and dynamic nonresonant (nuclear relaxation) vibrational (hyper)polarizabilities for a series of all‐trans polymethineimine (PMI) oligomers containing up to eight monomer units. These functionals are assessed against reference values obtained using the Møller–Plesset second‐order perturbation theory (MP2) and CCSD methods. For the smallest oligomer, CCSD(T) calculations confirm the choice of MP2 and CCSD as appropriate for assessing the density functionals. By and large, CAM‐B3LYP is the most successful, because it is best for the nuclear relaxation contribution to the static linear polarizability, intensity‐dependent refractive index second hyperpolarizability, static second hyperpolarizability, and is close to the best for the electro‐optical Pockels effect first hyperpolarizability. However, none of the functionals perform satisfactorily for all the vibrational (hyper)polarizabilities studied. In fact, in the case of electric field‐induced second harmonic generation all of them, as well as the Hartree–Fock approximation, yield the wrong sign. We have also found that the Pople 6–31+G(d) basis set is unreliable for computing nuclear relaxation (hyper)polarizabilities of PMI oligomers due to the spurious prediction of a nonplanar equilibrium geometry. © 2013 Wiley Periodicals, Inc. 相似文献