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61.
The Isbell, compact-open and point-open topologies on the set C(X,R) of continuous real-valued maps can be represented as the dual topologies with respect to some collections α(X) of compact families of open subsets of a topological space X. Those α(X) for which addition is jointly continuous at the zero function in Cα(X,R) are characterized, and sufficient conditions for translations to be continuous are found. As a result, collections α(X) for which Cα(X,R) is a topological vector space are defined canonically. The Isbell topology coincides with this vector space topology if and only if X is infraconsonant. Examples based on measure theoretic methods, that Cα(X,R) can be strictly finer than the compact-open topology, are given. To our knowledge, this is the first example of a splitting group topology strictly finer than the compact-open topology. 相似文献
62.
A new approach to the rapid determination of amoxicillin (AMO) in human plasma followed by solid phase microextraction (SPME) fiber coatings based on conducting polymers (polypyrrole and polythiophene) and high performance liquid chromatography (HPLC) has been described. The porous structures of the electrochemically deposited polymer coatings have been characterized by scanning electron microscopy (SEM). The experimental parameters relating to the extraction efficiency of the SPME fibers such as pH, extraction time and desorption conditions (solvents, time) were studied and selected. The SPME/HPLC-UV method was linear over a working range of 1-50 μg ml(-1). The inter-day accuracy (expressed as coefficients of variations, CVs) was less than 15% and precision (expressed as the relative standard deviations, RSDs) with percentage values was less than 5.9%. Amoxicillin was found to be stable in the human plasma at room temperature (20 °C) within 8 hours. The developed method was successfully applied to the analysis of real human plasma samples. The limit of detection and limit of quantification for amoxicillin in plasma were 1.21 μg ml(-1) and 3.48 μg ml(-1), respectively. 相似文献
63.
The framework of ab initio density-functional theory (DFT) has been introduced as a way to provide a seamless connection between the Kohn-Sham (KS) formulation of DFT and wave-function based ab initio approaches [R. J. Bartlett, I. Grabowski, S. Hirata, and S. Ivanov, J. Chem. Phys. 122, 034104 (2005)]. Recently, an analysis of the impact of dynamical correlation effects on the density of the neon atom was presented [K. Jankowski, K. Nowakowski, I. Grabowski, and J. Wasilewski, J. Chem. Phys. 130, 164102 (2009)], contrasting the behaviour for a variety of standard density functionals with that of ab initio approaches based on second-order M?ller-Plesset (MP2) and coupled cluster theories at the singles-doubles (CCSD) and singles-doubles perturbative triples [CCSD(T)] levels. In the present work, we consider ab initio density functionals based on second-order many-body perturbation theory and coupled cluster perturbation theory in a similar manner, for a range of small atomic and molecular systems. For comparison, we also consider results obtained from MP2, CCSD, and CCSD(T) calculations. In addition to this density based analysis, we determine the KS correlation potentials corresponding to these densities and compare them with those obtained for a range of ab initio density functionals via the optimized effective potential method. The correlation energies, densities, and potentials calculated using ab initio DFT display a similar systematic behaviour to those derived from electronic densities calculated using ab initio wave function theories. In contrast, typical explicit density functionals for the correlation energy, such as VWN5 and LYP, do not show behaviour consistent with this picture of dynamical correlation, although they may provide some degree of correction for already erroneous explicitly density-dependent exchange-only functionals. The results presented here using orbital dependent ab initio density functionals show that they provide a treatment of exchange and correlation contributions within the KS framework that is more consistent with traditional ab initio wave function based methods. 相似文献
64.
Aequationes mathematicae - We determine continuous bijections f, acting on a real interval into itself, whose k-fold iterate is the quasi-arithmetic mean of all its subsequent iterates from $$f^0$$... 相似文献
65.
A chemiluminescent flame was produced in the reaction between GeCl4 and an excited mixture of argon or helium with oxygen. Spectra of the reaction products were recorded and studied. Relative populations of the products in analyzed electronic, vibrational and rotational states corresponded to different temperatures. 相似文献
66.
P. Żenczykowski 《Zeitschrift fur Physik C Particles and Fields》1981,9(1):31-34
Properties of the decays of excited strange baryons into ground state baryon and pseudoscalar meson are examined in the framework of the linear baryonic string model. The agreement between the predictions and the data is good. The single model's parameter ε, the deviation of which from 1 measuresSU (3) breaking, is found to decrease with increasing internal orbital angular momentum of a baryon. 相似文献
67.
Antoni Gajewski Michal Życzkowski 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1970,21(5):806-818
Zusammenfassung Optimale Formen eines gedrückten elastischen Stabes werden bei allgemeinem Verhalten der Druckkraft nach dem Stabilitätsverlust untersucht. Als Zielfunktion wird das minimale Volumen angenommen unter der Nebenbedingung einer konstanten kritischen Belastung. Das konservative Verhalten der Kraft ist mit einer Beziehung verbunden, welche die allgemeine Euler-Lagrangesche Gleichung vereinfacht. Es werden räumlich sowie eben verjüngte Stäbe untersucht und die Resultate bei einigen Beispielen diskutiert. 相似文献
68.
U.J. Schrewe P. Tidemand-Petersson G.M. Gowdy R. Kirchner O. Klepper A. Płochocki W. Reisdorf E. Roeckl J.L. Wood J. Żylicz R. Fass D. Schardt 《Physics letters. [Part B]》1980,91(1):46-50
Using on-line mass separation of evaporation residues from heavy-ion-induced fusion reactions, three new isotopes were identified by their alpha decay, Eα given in keV: 183Pb, 6715(20), 184Pb, 6632(10) and 188Bi, 6820(20). Half-lives were determined for 184Pb, 0.55(6)s, 185Pb, 4.1(3)s and 183Tl, 0.060(15) s. The alpha branching ratios were re-measured for 182–184Hg and 178, 179Pt, the results are discussed within the framework of alpha width systematics. 相似文献
69.
P. Żenczykowski 《Physics letters. [Part B]》1979,80(3):298-301
A dynamical mechanism responsible for breaking of the SU(3) symmetry among various states from the s-u-d sector is proposed. In the case when SU(3) is dynamically maximally broken we obtain Λα - Λγ degeneracy and reproduce also other prominent features of the leading strange baryon trajectories. 相似文献
70.
A. Celler Ch. Briançon J.S. Dionisio A. Lefebvre Ch. Vieu J. Żylicz R. Kulessa C. Mittag J. Fernandez-Niello Ch. Lauterbach H. Puchta F. Riess 《Nuclear Physics A》1985,432(2):421-435
Yrast states in the nucleus 220Ra were studied by means of the 208Pb(14C, 2n) reaction at 61 and 64 MeV. A staggering sequence of levels of positive and negative parity has been observed up to spin and parity Iπ = 16+ (18 +) and from Iπ = 5? to Iπ = 17?, respectively. These states are connected by strong E1 transitions competing with the stretched E2 transitions, the ratio being ~ 10 ?6 fm?2. The ratio of the excitation energy of the 4+ state to that of the 2+ state is close to the vibrational limit. The moment of inertia associated with the negative-parity yrast states is slightly increasing with the rotational frequency ω. It is considerably higher than that of the positive-parity states at lower spins, the difference decreasing monotonically with increasing ω. The data are discussed with reference to the octupole vibrational picture as well as to the results of recent models predicting reflection-asymmetric shapes in the Ra-Th region. 相似文献