Nonlinear multiple objective optimization: An algorithm and some theory

This paper presents an algorithm and the supporting theory for solving a class of nonlinear multiple criteria optimization problems using Zionts—Wallenius type of interaction. The Zionts—Wallenius method, as extended in this paper, can be used for solving multiple criteria problems with concave objective and (implicit) value functions and convex feasible regions. Modifications of the method to handle nonconvex feasible regions and general nonlinear objective functions are also discussed.This research was supported, in part, by a Faculty Research Development Award and by a Council of 100 Research Grant from Arizona State University (Roy), and by a grant from Y. Jahnsson Foundation, Finland (Wallenius). The research was performed while the second author was a Visiting Professor at Arizona State University.     

Working group report: Neutrino and astroparticle physics

This is the report of neutrino and astroparticle physics working group at WHEPP-7. Discussions and work on CP violation in long baseline neutrino experiments, ultra high energy neutrinos, supernova neutrinos and water Cerenkov detectors are discussed.     

Röntgenstrahlenbeugung bei hohen Temperaturen zur Untersuchung der thermischen Ausdehnung von MnSe und MnSe2

Zusammenfassung Durch Röntgenstrahlenbeugung mit Hilfe einer 190 mm Unicam-Hochtemperaturkamera wurde die thermische Ausdehnung von MnSe und MnSe₂ von Zimmertemperatur bis 710° bzw. 522° C untersucht. Der thermische Ausdehnungskoeffizient wurde aus den Meßdaten nach der Methode der kleinsten Fehlerquadrate erhalten und beträgt für MnSe: =24,5·10^–6°C^–1 (94–450° C) und =14,3·10^–6°C^–1 (450–710° C). Die Ausdehnung von MnSe₂ verläuft bis zum Bereich, in dem Zersetzung eintritt, linear. Die Methode der kleinsten Fehlerquadrate ergibt den Wert =20,0·10^–6°C^–1 (73–522° C).

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High temperature X-ray studies of the thermal expansion ofMnSe andMnSe ₂

The thermal expansion of MnSe and MnSe₂ has been studied above room temperature up to 710° and 522° C, resp., by X-ray diffraction techniques using a 190 mm Unicam high temperature camera. The thermal expansion coefficients, , obtained from a linear least-squares analysis of the data are for MnSe: =24.5·10^–6°C^–1 (94–450° C) and =14.3·10^–6°C^–1 (450–710° C). The expansion of MnSe₂ is linear up to the temperature range of decomposition. A least-squares analysis yields a value for of 20.0·10^–6°C^–1 (73–522° C).

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Mit 2 Abbildungen

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Herrn Prof.H. Nowotny gewidmet.     

Free energies of transfer of alkali halides from water to urea-water mixtures at 25°C from EMF measurements

The standard potentials_s E ^o of M/M⁺ (M=Li, Na, K, Rb, and Cs) electrodes in aqueous urea solutions containing 12, 20, 30 and 37% by weight of urea have been determined at 25°C from emf measurements on the cell M(Hg)/MCl (m), solvent/AgCl–Ag, from the activities of metals in amalgams by use of a similar type of cell in water, and from the values of_s E ^o of the Ag/AgCl electrode determined earlier. The standard free energies of transfer of MCl, G _t ^o (MCl), from water to the mixed solvents, computed by use of these values and those for the Ag–AgCl electrode, rise sharply from Li⁺ to Na⁺ but fall from Na⁺ to K⁺ and rather sharply from K⁺ to Cs⁺ with a maximum at Na⁺ in all the solvent compositions. This has been attributed to the superimposition of soft-soft interactions on the electrostatic interactions between the ions and the negative charge centers of the possible hydrogen-bonded solvent complexes in the mixed solvents. Comparison of G _t ^o (i) values for individual ions, obtained by a simultaneous extrapolation procedure, with those in aqueous mixtures of methanol,t-butanol, and dimethyl sulfoxide leads to the conclusion that the solvation of these ions in all these solvents is chiefly dictated by the acid-base type of ion-solvent interactions.     

Kinetics and mechanism of oxidation of 8-hydroxyquinoline and its derivatives by cerium(IV) through precursor complex formation

Summary In acid (HClO₄) medium Ce^IV is reduced to Ce^III by 8-hydroxyquinoline (1) and its derivatives, the 5-sulphonate (2) and 7-iodo-5-sulphonate (3), through precursor complex formation. The rates of precursor complex formation have been studied by stopped-flow spectrophotometry for both (1) and (2). Formation of the precursor complex occurs in two concurrent paths involving Ce _aq ⁴⁺ and [Ce(OH)] _aq ³⁺ reacting by I_a and I_d processes respectively. The reaction with (3) is, however, too fast for the stopped-flow method. The rates for subsequent intramolecular electron transfer processes in the precursor complexes are sufficiently slow for all the three species(1)–(3) for evaluation by conventional spectrophotometry. For the electron transfer process the rate varies in the sequence:(2)>(1)(3) due to electron-withdrawing character of the substituent SO ₃ ^– and electron-releasing character of I.     

Oxofluorovanadates(V). IV. Dioxotetrafluorovanadates

Preparation and properties of the salts of the series MVO₂F₄, where M = NH, Na⁺, K⁺, 1/2 Ni²⁺, and 1/3 [Co(NH₃)₆]³⁺ are described. Molecular conductivity of Na₃VO₂F₄ at different dilutions indicates that Na₃VO₂F₄ dissociates into 3 Na⁺ and VOaF ions. Ion exchange study of (NH₄)₃VO₂F₄ solution through cation exchange resin (H⁺ form) suggests that the corresponding acid decomposes partly to vanadium pentoxide. Reaction between (NH₄)₃VO₂F₄ with BaCl₂ and AgNO₃ solutions shows the formation of BaVO₂F₃ and AgVO₃ respectively. Thermogravimetric study of (NH₄)₃VO₂F₄ shows the formation of impure vanadium pentoxide as the ultimate product on heating up to 450°C. X-ray powder diffraction data are given for (NH₄)₃VO₂F₄ and Na₃VO₂F₄.     

Studies on the kinetics and mechanism of dissociation of copper(II) and nickel(II) complexes of the macrocyclic ligand 1, 5, 9, 13-tetraaza-2, 4, 4, 10, 12, 12-hexamethyl-cyclohexadecane-1, 9-diene in perchloric acid media

Summary Acid catalysed dissociation of the copper(II) and nickel(II) complexes (ML²⁺ of the quadridentate macrocyclic ligand 1, 5, 9, 13-tetraaza-2, 4, 4, 10, 12, 12-hexamethyl-cyclohexadecane-1, 9-diene (L) has been studied spectrophotometrically. Both complexes dissociate quite slowly with the observed pseudo-first order rate constants (k_obs) showing acid dependence; for the nickel(II) complex (k_obs)=k_O+k_H[H⁺], the k_o path is however absent with the copper(II) complex. At 60°C (I=0.1M) the k_H values areca 10^–4 M^–1 s^–1 for both complexes; k _H ^Cu /k _H ^Ni =ca. 3.9, comparable to some other square-planar complexes of these metal ions. The rate difference is primarily due to H values [copper(II) complex, 29.4±0.5 kJ mol^–1; nickel(II) complex, 35.6±1.5 kJ mol^–1] with highly negative S values [for copper(II), –215.5 ±6.1 JK^–1 mol^–1 and for nickel(II), –208.1 ±5.6 JK^–1 mol^–1] which are much higher than the entropy of solvation of Ni²⁺ (ca. –160 JK^–1 mol^–1) and Cu²⁺ (ca. –99 JK^–1 mol^–1) ions; significant solvation of the released metal ions and the ligand is indicated.     

Kinetics and mechanism of reactions of bis(biguanide)copper(II) ion with 2,2′-bipyridyl and 1,10-phenanthroline in aqueous solution

Summary In aqueous solution [Cu(bigH)₂]²⁺ (bigH=biguanide) reacts with 2,2-bipyridyl (bipy) and 1,10-phenanthroline (phen) through intermediate formation of ternary complexes [Cu(bigH)(L)]²⁺ and [Cu(bipy)(phen)]²⁺ and binary complexes [CuL₂]²⁺ (L=bipy, phen). The rates of the different steps have been followed in borax buffer (pH 8.0±0.1) by stopped-flow spectrophotometry. For each step k_obs=k₀+k_L[L] and the k_L path appears to be associative. H and S values for the k_L path conform to an isokinetic trend.     

The microwave spectrum and structure of trifluoro-ethylene

The microwave spectrum of trifluoroethylene F₂C=CHF is reported, and a number of ground state and vibrationally excited state lines are assigned. The ground state rotational constants are: 10665.31, 3872.36, 2837.97 MHz. The dipole components are μ_a = 0.075 D, μ_b = 1.30 D, and μ_total = 1.30 D. Calculations of the inertia defect of the ground and excited states indicate that the equilibrium configuration is planar.