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101.
102.
The evolution of a two-level system subjected to stimulated transitions which is undergoing a sequence of measurements of
the level occupation probability is evaluated. Its time correlation function is compared to the one obtained through the pure
Schr?dinger evolution. Systems of this kind have been recently proposed for testing the quantum mechanical predictions against
those of macrorealistic theories, by means of temporal Bell inequalities. The classical requirement of noninvasivity, needed
to define correlation functions in the realistic case, finds a quantum counterpart in the quantum nondemolition condition.
The consequences on the observability of quantum mechanically predicted violations to temporal Bell inequalities are drawn
and compared to the already dealt case of the rf-SQUID dynamics.
Received: 28 March 1996 / Revised version: 13 August 1996 相似文献
103.
Tommaso Schiavinotto Thomas Stützle 《Journal of Mathematical Modelling and Algorithms》2004,3(4):367-402
The linear ordering problem is an NP-hard problem that arises in a variety of applications. Due to its interest in practice, it has received considerable attention and a variety of algorithmic approaches to its solution have been proposed. In this paper we give a detailed search space analysis of available benchmark instance classes that have been used in various researches. The large fitness-distance correlations observed for many of these instances suggest that adaptive restart algorithms like iterated local search or memetic algorithms, which iteratively generate new starting solutions for a local search based on previous search experience, are promising candidates for obtaining high performing algorithms. We therefore experimentally compared two such algorithms and the final experimental results suggest that, in particular, the memetic algorithm is a new state-of-the-art approach to the linear ordering problem. 相似文献
104.
A rapid and very sensitive method for the accurate determination of free iodide in real samples is described. The method is based on anion-exchange chromatographic separation coupled with amperometric detection at a modified platinum electrode under constant applied potential (+0.85 V vs. Ag AgCl). An experimental setup with an in-line and very effective method of electrode modification is proposed using an amperometric thin-layer cross-flow detector and a flowing solution 300 mg/L of iodide; the working electrode is polarised to the limiting current for oxidation of iodide to iodine in acidic solutions with the consequent formation of an iodine-based film. The results indicated that the modified electrode exhibits high analytical response for iodide electrooxidation with good stability and long-life. The signal intensity of daily experimental sessions (8 h), during which standards and real samples were repeatedly injected, exhibits a moderate lowering (i.e. <6%). Using a mixture of 25 mM HNO3 and 50 mM NaNO3 as an eluent phase in ion-exchange chromatography, the detection limit of iodide was estimated to be 0.5 g/L (S/N=3) with an injection volume of 50 L. This method was applied successfully to quantify the iodide content of milk samples and in wastewaters as well as trace amounts in common vegetables and solutions containing high chloride levels. 相似文献
105.
The second dissociation constant of salicylic acid (H2L) has been determined, at 25 degrees C, in NaCl ionic media by UV spectrophotometric measurements. The investigated ionic strength values were 0.16, 0.25, 0.50, 1.0, 2.0 and 3.0 M. The protolysis constants calculated at the different ionic strengths yielded, with the Specific Interaction Theory, the infinite dilution constant, log beta1(0) = 13.62 +/- 0.03, for the equilibrium L2- + H+ <==> HL-. The interaction coefficient between Na+ and L2-, b(Na+, L2-) = 0.02 +/- 0.07, has been also calculated. 相似文献
106.
107.
108.
Dr. Alberto Verdini Dr. Prashant Shinde Dr. Gian Luca Montanari Dr. Simone Tommaso Suran‐Brunelli Dr. Marco Caputo Dr. Giovanni Di Santo Dr. Carlo A. Pignedoli Dr. Luca Floreano Prof. Daniele Passerone Dr. Andrea Goldoni 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(41):14672-14677
Herein the formation of water molecules in the intermediate step of the redox reaction of porphyrins self‐metalation on O/Cu(111) is demonstrated. Photoemission measurements show that the temperature on which porphyrins pick‐up a substrate metal atom on O/Cu(111) is reduced by about 185±15 K with respect to the pure Cu(111). DFT calculations clearly indicate that the formation of a water molecule is less expensive than the formation of H2 on the O/Cu(111) substrate and, in some cases, it can be also exothermic. 相似文献
109.
110.