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161.
José Luiz Boldrini Luís H. de Miranda Gabriela Planas 《Journal of Evolution Equations》2013,13(3):535-560
This article considers the issues of existence and regularity of solutions to the following doubly nonlinear differential inclusion $$\omega_t+\alpha (\omega_t)-\Delta \omega-\Delta_p{\omega} \ni f$$ where α is a maximal monotone operator in ${\mathbb{R}^2}$ and Δ p denotes the p-Laplacian with p > 2. The investigation on fractional regularity is based on the Galerkin method combined with a suitable basis for W 1,p , which we exhibit as a preliminary result. This approach also allows the obtaining of estimates in the so-called Nikolskii spaces, since it balances the interplay between the maximal monotone operator with the appearing higher order nonlinear terms. 相似文献
162.
Lenize F. Maia Vanessa E. de Oliveira Maria E. R. Oliveira Felipe D. Reis Beatriz G. Fleury Howell G. M. Edwards Luiz F. C. de Oliveira 《Journal of Raman spectroscopy : JRS》2013,44(4):560-566
Polyenic pigments in octocorals have been investigated by Raman spectroscopy using laser excitation at 532, 785 and 1064 nm. The spectral features suggest the structural nature of carotenoids from Phyllogorgia dilatata, Leptogorgia punicea, Muricea atlantica, Carijoa riisei and conjugated polyenals from L. punicea, L. setacea, Muricea flamma and Renilla muelleri. The observed vibrational bands at ca. 1540–1520 ν1(C=C), 1159 ν2(C–C) and 1005 cm−1 ρ3(C–CH3) were assigned to carotenoids, whereas the identification of non‐methylated conjugated polyenals have been proposed due to two major Raman bands at ca. 1500 and 1120 cm‐1, assigned to ν(C=C) and ν(C–C), respectively. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
163.
Luiz F. Lepre Fabiana Inoue Paola Corio Paulo S. Santos Rmulo A. Ando 《Journal of Raman spectroscopy : JRS》2013,44(4):567-572
The spectroscopic characterization of cadion or 1‐(4‐nitrophenyl)‐3‐(4‐phenylazophenyl)triazene, its anionic species and its complexes with Hg2+, Cd2+ and Ni2+ in DMSO solution is presented. Resonance Raman (RR) and UV–vis spectroscopy were the techniques of choice with results supported by density functional theory calculations. As previously reported, the UV–vis data indicate distinct absorption spectra for the five species mentioned, allowing for spectrophotometric metal differentiation. In order to understand the electronic spectra of such species, we performed a detailed RR investigation, where the spectral profiles revealed the vibrational modes mainly involved in the chromophoric moieties. The distinct enhancement profile observed for each species suggests that the charge transfer from the π‐system to the electron withdrawing NO2 group is modulated by the electron donating triazene moiety, depending on the metal attached. The results reported herein show that RR spectroscopy can be potentially used in the metal detection of multicomponent samples by the proper choice of the excitation wavelength. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
164.
Lyn R. Watson Terry L. Thiem Rainer A. Dressler Richard H. Salter Edmond Murad 《光谱学快报》2013,46(4):661-676
Abstract A position-sensitive ion detection system for trace analysis with magnetic sector mass spectrometers is described in detail, with particular application to high temperature mass spectrometry. The detection system consists of two stacked microchannel plates (Chevron assembly) backed by a resistive anode encoder and associated electronics. The range of masses simultaneously detectable is m to 1.2m. For electron impact ionization of silver at an electron energy of 10.5 eV, the sensitivity is 1.6 × 10?7 Pa, and the mass resolution is 260 at mass 80 (valley 10% of the peak height definition). Additional applications for the detection system are discussed. 相似文献
165.
Let ${\mathcal P}$ be a partial order and ${\mathcal A}$ an arboreal extension of it (i.e. the Hasse diagram of ${\mathcal A}$ is a rooted tree with a unique minimal element). A jump of ${\mathcal A}$ is a relation contained in the Hasse diagram of ${\mathcal A}$ , but not in the order ${\mathcal P}$ . The arboreal jump number of ${\mathcal A}$ is the number of jumps contained in it. We study the problem of finding the arboreal extension of ${\mathcal P}$ having minimum arboreal jump number—a problem related to the well-known (linear) jump number problem. We describe several results for this problem, including NP-completeness, polynomial time solvable cases and bounds. We also discuss the concept of a minimal arboreal extension, namely an arboreal extension whose removal of one jump makes it no longer arboreal. 相似文献
166.
Cristiane Kalinke Paulo Roberto de Oliveira Marta Bonet San Emeterio Andreu Gonzlez‐Calabuig Manel del Valle Antonio Salvio Mangrich Luiz Humberto Marcolino Junior Mrcio F. Bergamini 《Electroanalysis》2019,31(11):2238-2245
Biochar is a charcoal produced from the biomass pyrolysis process that presents a highly porous and functionalized surface. In the present work an array of carbon paste electrodes (CPE) made of different forms of carbon (graphite, carbon nanotubes and activated biochar) was evaluated in the development of an electronic tongue for discrimination and stripping voltammetric determination of catechol (CAT), 4‐ethylcatechol (4‐EC) and 4‐ethylguaiacol (4‐EG) phenolic compounds. Morphological characterization of carbon materials and electrodes surfaces was performed by scanning electron microscopy (SEM) and semi‐quantitative elemental composition by energy dispersive spectroscopy (EDS). Electrochemical Impedance Spectroscopy (EIS) measurements were used for electrochemical characterization of electrodes. Cyclic voltammetry measurements were performed for the phenolic compounds evaluated using different concentrations. Principal component analysis (PCA) was performed to evaluate the qualitative analysis. Quantitative data modeling was done using artificial neural networks (ANN). The proposed sensor array presented analytical potentiality allowing the distinction and determination of CAT, 4‐EC and 4‐EG by using chemometric processing. The method showed sensibility, reproducibility and a good linearity (R2>0.9940) for three compounds evaluated. Spontaneous preconcentration of three compounds was possible using all three sensors, which can allow the application of these as passive samplers for remote determinations of phenolic compounds in wine and food samples. 相似文献
167.
Pires Osmar Antonio Baldo Alarcon Rafael Turra Gaglieri Caroline da Silva-Filho Luiz Carlos Bannach Gilbert 《Journal of Thermal Analysis and Calorimetry》2019,137(1):171-173
Journal of Thermal Analysis and Calorimetry - In the original publication of the article, the Figures 6, 7, and 8 are in disagreement with their figure captions. Moreover, in the result... 相似文献
168.
Issa JP Spadaro AC Bentley MV Iyomasa MM Siéssere S Regalo SC Defino HL 《Micron (Oxford, England : 1993)》2008,39(7):952-959
The purpose of this work was to evaluate the new bone tissue, comparing two different carriers for rhBMP-2, monoolein and chitosan gels, using the decortication and nondecorticatication surgical technique in rat mandibles, evaluated by histomorphometrical method. It was used 56 male Wistar rats (300g), divided into 8 groups according to the rhBMP-2 carrier used, monoolein or chitosan gels; surgical technique, bone decortication or nondecortication; and period of time, 3 or 6 weeks until the sacrifice by perfusion. Results obtained in this study showed that the rhBMP-2/monoolein and rhBMP-2/chitosan used in this experimental model was able to induce osteogenesis, contributing to the bone healing process. The bone repair process was time dependent, so that at 6 weeks there was an improved amount of new bone in relation to 3 weeks, considered each analyzed group, and the decortication was able to expose the bone marrow and speed up the bone healing process, which was showed by histomorphometrical methods. Both of carriers were capable to adapt to the bone surgical area, according to the clinical observations, and had favorable properties in relation to protein releasing, revealed by the amount of new bone tissue found in the histological analysis. 相似文献
169.
Marcos Malta Luiz Henrique Silva Andr Galembeck Mauro Korn 《Macromolecular rapid communications》2008,29(14):1221-1225
A single‐step sonochemical procedure to synthesize hybrid vanadium oxide/polyaniline nanowires starting from crystalline V2O5 and aniline in aqueous medium is presented. The synthesis explores the effect of high power ultrasounds on heterogeneous solid–aqueous phases, which leads to 30 nm width wires of 5 to 10 µm in length. Monomer intercalation and oxidative polymerization within the inorganic matrix proceed simultaneously with morphological changes. The electronic conductivity of hybrid nanowires reaches 0.8 S · cm−1 at room temperature.
170.
Juan Manuel Cornejo Luiz F. Monteiro Hanamantagouda P. Sankappanavar Ignacio D. Viglizzo 《Mathematical Logic Quarterly》2020,66(4):409-417
We determine the number of non-isomorphic semi-Heyting algebras on an n-element chain, where n is a positive integer, using a recursive method. We then prove that the numbers obtained agree with those determined in [1]. We apply the formula to calculate the number of non-isomorphic semi-Heyting chains of a given size in some important subvarieties of the variety of semi-Heyting algebras that were introduced in [5]. We further exploit this recursive method to calculate the numbers of non-isomorphic semi-Heyting chains with n elements such that removing the mth element () we are left with a subalgebra. We also solve a related problem posed in [1] of determining the number of ways a semi-Heyting chain with elements can be extended to a n element semi-Heyting chain by adding a new element in the mth place. Finally we combine these results by finding a second way to calculate the numbers that provides some extra information. 相似文献