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91.
Bound state solutions of D‐dimensional schrödinger equation with exponential‐type potentials
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José Juan Peña Jesús García‐Martínez Jesus García‐Ravelo Jesus Morales 《International journal of quantum chemistry》2015,115(3):158-164
In this article, using an exactly‐solvable multiparameter exponential‐type potential we propose a unified treatment of the analytical bound—state solutions of the Schrödinger equation for exponential‐type potentials in D‐dimensions. Our proposal accepts different approximations to the centrifugal term; however, its usefulness is exemplified in the frame of the Green and Aldrich approach. This fact enables us to compare our results with specific potentials found in the literature and that are obtained here as particular cases of our proposal. That is, instead of solving a specific exponential‐type potential, by resorting each time to a specialized method, the energy spectra and wavefunctions are derived straightforward from the proposed approach. Furthermore, our proposal can be used as an alternative way in the search of solutions to new exponential‐type potentials besides that one can study different approximations to the term . © 2014 Wiley Periodicals, Inc. 相似文献
92.
Maria Jesus Jimnez‐Come Ignacio J. Turias Juan Jesus Ruiz‐Aguilar Francisco J. Trujillo 《Journal of Chemometrics》2014,28(3):181-191
The breakdown potential is a crucial factor in the study of pitting corrosion resistance of stainless steel. This work aims to demonstrate the advantage of different chemometric techniques to estimate the breakdown potential of austenitic stainless steel. In order to predict pitting corrosion behaviour of stainless steel, a total of 60 samples of this alloy were subjected to electrochemical tests varying chloride ion concentration, pH and temperature. The experimental values of the breakdown potential, in addition to the tested environmental factors, were used to construct the predictive models based on support vector machines and artificial neural networks. A multiple‐comparison study based on statistic tests was applied to determine the optimal configuration for each technique. According to the results, support vector machines became a suitable and reliable technique to be applied in the modelling of the breakdown potential of austenitic stainless steels. This technique outperformed the models based on artificial neural networks and provided a useful tool to compare the pitting corrosion resistance of stainless steel in different environmental conditions without recourse to polarization tests. Therefore, this model presented a relevant meaning in science and engineering applications. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
93.
A new approach for target quantitative analysis for comprehensive two-dimensional gas chromatography (GC × GC), interval Multi-way Partial Least Square (iNPLS) is presented and evaluated in this paper. In iNPLS, the two-dimensional chromatogram is split in small sections; each of these pieces is treated as an independent new chromatogram. Separated conventional NPLS calibration models for the concentration of the target analyte are built for each of the pieces of the whole chromatogram, and the best model is selected for quantitative analysis. An algorithm for iNPLS running on MatLab platform was written, preliminarily evaluated with using solutions of model compounds with different chemical properties and subsequently applied to quantify some allergens in perfume samples. The results were found to be adequate, and good precision and accuracy was obtained even for poorly resolved peaks. 相似文献
94.
Singh P Toma FM Kumar J Venkatesh V Raya J Prato M Verma S Bianco A 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(24):6772-6780
Single‐walled carbon nanotubes (SWCNTs) have been covalently functionalized with uracil nucleobase. The hybrids have been characterized by using complementary spectroscopic and microscopic techniques including solid‐state NMR spectroscopy. The uracil‐functionalized SWCNTs are able to self‐assemble into regular nanorings with a diameter of 50–70 nm, as observed by AFM and TEM. AFM shows that the rings do not have a consistent height and thickness, which indicates that they may be formed by separate bundles of CNTs. The simplest model for the nanoring formation likely involves two bundles of CNTs interacting with each other via uracil–uracil base‐pairing at both CNT ends. These nanorings can be envisaged for the development of advanced electronic circuits. 相似文献
95.
De Jesus RM Junior MM Matos GD Dos Santos AM Ferreira SL 《Journal of AOAC International》2011,94(3):942-946
This paper presents the validation of a system for sample digestion using a digester block/cold finger to determine the lead content in vegetables by electrothermal atomic absorption spectrometry (ETAAS). After mineralization, lead contents were determined by ETAAS using a calibration curve based on aqueous standards prepared in 2.60 M nitric acid solutions containing 5 microg ammonium phosphate as chemical modifier. A pyrolysis temperature of 900 degrees C and atomization temperature of 2000 degrees C were used. This method allowed the determination of lead with a characteristic mass of 35 pg; LOD and LOQ of 0.6 and 2 nglg, respectively, were found. The precision was investigated in terms of reproducibility and repeatability. Reproducibility was estimated by analysis of nine different portions of a certified reference material (CRM) of spinach leaves, and the repeatability was determined through the analysis of nine aliquots of the same solution. The reproducibility and repeatability were found to be 4.27 and 2.94% RSD, respectively. The accuracy was confirmed by analysis of whole meal flour, spinach leaves, and orchard leaves CRMs, all furnished by the National Institute of Standards and Technology. Lead contents were measured using the newly developed technique in 11 different potato samples. The lead contents ranged from 12.80 to 69.27 ng/g, with an average value of 28.59 ng/g. These values were in agreement with data reported in the literature. 相似文献
96.
Lalueza P Monzón M Arruebo M Santamaria J 《Chemical communications (Cambridge, England)》2011,47(2):680-682
We show that Ag-containing zeolites are highly effective against Staphylococcus aureus (SA) bacteria even at low Ag loadings and in the presence of high (10(9) CFU per mL) bacterial concentrations. At short contact times the bactericidal efficiency correlates strongly with Ag(+) release. At longer times data dispersion is higher, probably as a consequence of bacterial metabolism. 相似文献
97.
We study large time asymptotic behavior of solutions to the periodic problem for the nonlinear Burgers type equation
$ \left\{ {l} \psi_{t}=\psi_{xx}+\lambda \psi +\psi \psi_{x},\quad x\in \Omega, \quad t >0 , \\ \psi (0,x)=\widetilde{\psi}(x), \quad x\in \Omega, \right. $ \left\{ \begin{array}{l} \psi_{t}=\psi_{xx}+\lambda \psi +\psi \psi_{x},\quad x\in \Omega, \quad t >0 , \\ \psi (0,x)=\widetilde{\psi}(x), \quad x\in \Omega, \end{array} \right. 相似文献
98.
Among the most frequent protein binding sites served by Mg(II), we identify those which have higher affinity towards Al(III). We also estimate the free energies of metal exchange for all these binding sites taking into account solvent effects explicitly. The obtained results show that thermodynamically favored Mg(II)/Al(III) exchange reactions take place at a number of these metal binding sites, which could possibly be related to some dysfunctions of Mg(II)-dependent biological processes. Additionally, they shed light on the molecular basis of the toxicity of Al(III) in living organisms. 相似文献
99.
F. Raiola B. Burchard Zs. Fülöp Gy. Gyürky S. Zeng J. Cruz A. Di Leva B. Limata M. Fonseca H. Luis M. Aliotta H. W. Becker C. Broggini A. D'Onofrio L. Gialanella G. Imbriani A. P. Jesus M. Junker J. P. Ribeiro V. Roca C. Rolfs M. Romano E. Somorjai F. Strieder F. Terrasi 《The European Physical Journal A - Hadrons and Nuclei》2006,27(1):79-82
100.
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