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171.
In this paper, a new proposal of the quantum potential theory is presented, along with a discussion of the two-slit interference experiment and the Aharonov-Bohm effect, which are explicitly calculated within the scheme adopted. The present formulation holds the notion of particle trajectory and follows the interpretation suggested by de Broglie and Bohm, the quantum potential being a manifestation of the quantum wave. This wave always satisfies the Schrödinger equation and is considered as areal and separate entity from the particle with which is associated. In our approach we try to circumvent some conceptual difficulties that prevent the de Broglie-Bohm's theory from fulfilling a complete objective program. New effects are predicted, specially for the Aharonov-Bohm experiment in the regime of high magnetic fields, and a setup for their detection is proposed. 相似文献
172.
A. Calles E. Yepez J. J. Castro A. Salcido A. Cabrera R. Gomez S. Aburto V. Marquina M. L. Marquina M. Jimenez R. Escudero 《Hyperfine Interactions》1991,66(1-4):429-433
The Jahn-Teller distortion mechanism in the Nd2?x Ce x CuO4 is analyzed. This analysis is based on a quasi-molecular model for the CuO4 cluster havingD 4h symmetry. In order to compare with experimental Mössbauer measurements in the doped Nd1.85Ce0.15Cu0.99Fe0.01O4?δ superconductor, the FeO4 cluster is also analyzed for the case of Fe2+ in the high spin state. The results show not evidence of a Jahn-Teller effect in these superconductors. 相似文献
173.
Pankaj Sharma Armando Cabrera Cecilio Alvarez Noe Rosas Elizabeth Gomez Alfredo Toscano 《Analytical sciences》2003,19(9):1341-1342
Crystal structure of trans-dibromobis(triphenylphosphine)platinum(II) was determined by X-ray-crystallography. The complex crystallizes on an inversion center in distorted square planar coordination around platinum with triphenylphosphine ligands in trans positions to each other and with two molecules of dichloromethane as solvate. 相似文献
174.
J. M. Navarrete J. Campos T. Martínez L. Cabrera 《Journal of Radioanalytical and Nuclear Chemistry》2005,265(1):133-135
Summary After the Chernobyl accident in April 1986, Mexico imported from one European country a shipment of 28,000 tons of milk powder contaminated with the fission product 137Cs. Since then, the local authorities of Public Health have established as a compulsory condition to obtain through gamma-spectroscopy a certificate of no radioactive contamination either to imported or exported foodstuffs. But at the same time, the absence of long-lived, gamma-emitters fission products is certified, it is also possible to find the concentration of the important trace element K in foodstuffs, by the peak of 1461 keV from 40K, invariably present in the gamma-spectra. Taking advantage of the fact that it does not require any previous manipulation of the sample, this paper describes the general procedure in milk powder or any other foodstuff. 相似文献
175.
176.
Alvarez-Manzaneda EJ Chahboun R Cabrera E Alvarez E Haidour A Ramos JM Alvarez-Manzaneda R Hmamouchi M Bouanou H 《The Journal of organic chemistry》2007,72(9):3332-3339
A new synthetic strategy toward puupehenone-related bioactive metabolites from sclareol oxide, based on a Diels-Alder cycloaddition approach, is described. Utilizing this, marine ent-chromazonarol and the potent angiogenesis inhibitor 8-epipuupehedione have been synthesized. 相似文献
177.
Vélez Carlos A. Soto-Pérez Joesene J. Corchado-García Juan Larios Eduardo Fulvio Pasquale F. Echegoyen Luis Cabrera Carlos R. 《Journal of Solid State Electrochemistry》2021,25(1):207-217
Journal of Solid State Electrochemistry - The glucose oxidation reaction, at Pd on unsupported carbon nano-onions (Pd/CNOs), has been studied by using physical and electrochemical characterization... 相似文献
178.
Francesca Coppola Luigi Picariello Martino Forino Luigi Moio Angelita Gambuti 《Molecules (Basel, Switzerland)》2021,26(4)
Background: Three accelerated oxidation tests were proposed to simulate red wine oxidation thus providing information useful to correctly manage moderate oxygen exposure of wine during aging in regard to phenolic composition and wine color. Since the results of the tests have never been compared on wines with different initial composition, the aim of this study was to find a suitable method to simulate oxidation of any still red wine. Methods: Aglianico, Barbera, Gaglioppo, Magliocco, and Nerello wines were treated with (1) three cycles of air saturation, (2) the addition of hydrogen peroxide, and (3) the addition of acetaldehyde. Changes in chromatic characteristics and phenolic composition were determined by spectrophotometric and HPLC methods. Results: Important differences in the behavior of the different wines were detected: the highest formation of polymeric pigments was observed in Barbera and Aglianico wines. In contrast, Gaglioppo and Magliocco wines showed a lower variability before and after the oxidation probably due to the lower anthocyanin/tannin ratio. Among the accelerated oxidation tests applied, no significant differences in color parameters and phenolic composition were detected in samples treated with the addition of H2O2 and the air saturation method. Conclusion: The study demonstrated that H2O2 addition is a successful tool to predict the evolution of different phenolic compounds during the air saturation treatment of wines. 相似文献
179.
Hartman–Wintner‐type inequalities for a class of nonlocal fractional boundary value problems 下载免费PDF全文
In this paper, we establish new Hartman–Wintner‐type inequalities for a class of nonlocal fractional boundary value problems. As an application, we obtain a lower bound for the eigenvalues of corresponding equations. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
180.