Search results for "solution"
showing 10 items of 5638 documents
Representation of solutions and large-time behavior for fully nonlocal diffusion equations
2017
Abstract We study the Cauchy problem for a nonlocal heat equation, which is of fractional order both in space and time. We prove four main theorems: (i) a representation formula for classical solutions, (ii) a quantitative decay rate at which the solution tends to the fundamental solution, (iii) optimal L 2 -decay of mild solutions in all dimensions, (iv) L 2 -decay of weak solutions via energy methods. The first result relies on a delicate analysis of the definition of classical solutions. After proving the representation formula we carefully analyze the integral representation to obtain the quantitative decay rates of (ii). Next we use Fourier analysis techniques to obtain the optimal dec…
Crystal structure and microstructure of synthetic hexagonal magnesium–cobalt cordierite solid solutions (Mg2−2xCo2xAl4Si5O18)
2013
Co2+-containing cordierite glasses, of nominal compositions (Mg1−xCox)2Al4Si5O18(withx= 0, 0.2, 0.4, 0.6, 0.8 and 1), were prepared by melting colloidal gel precursors. After isothermal heating at 1273 K for around 28 h, a single-phase α-cordierite (high-temperature hexagonal polymorph) was synthesized. All materials were investigated using X-ray powder diffraction and field-emission scanning electron microscopy. The crystal structure and microstructure were determined from X-ray diffraction patterns. Rietveld refinement confirmed the formation of magnesium–cobalt cordierite solid solutions. The unit-cell volume increased with the increase of cobalt content in the starting glass. The crysta…
X-ray powder diffraction study of monoclinic V4+-ZrO2 solid solutions obtained from gels
2003
Abstract Rietveld refinement of six monoclinic V x Zr 1− x O 2 solid solutions, with x =0, 0.01, 0.02, 0.05, 0.075 and 0.1, prepared by heating dried gel precursors at 1300°C in air atmosphere, has been characterized using X-ray powder diffractometer data. The present results confirm that crystal structure of these solid solutions contain V 4+ (Zr 4+ ) cations surrounded by seven oxygens, four at a distance between 2.13 and 2.28 A (referred as to O(2) in the tetrahedrally coordinated oxygens) and other three at a distance between 2.03 and 2.20 A (denoted as O(1) in the triangularly coordinated oxygens). The trends in the lattice parameter variation of V x Zr 1− x O 2 solid solutions specime…
X-ray absorption spectroscopic study of trivalent and tetravalent actinides in solution at varying pH values
2009
Abstract We perform X-ray absorption spectroscopy (XAS) investigations to monitor the stabilization of redox sensitive trivalent and tetravalent actinide ions in solution at acidic conditions in a pH range from 0 to 3 after treatment with holding reductants, hydroxylamine hydrochloride (NH2OHHCl) and Rongalite (sodium hydroxymethanesulfinate, CH3NaO3S). X-ray absorption near edge structure (XANES) measurements clearly demonstrate the stability of the actinide species for several hours under the given experimental conditions. Hence, structural parameters can be accurately derived by extended X-ray absorption fine structure (EXAFS) investigations. The coordination structure of oxygen atoms be…
Decalcifying effects of antimicrobial irrigating solutions on root canal dentin
2012
Objective: The aim of this study was to determine the decalcifying efficacy of 7% maleic acid (MA), 2% chlorhexidine (CHX), and combinations of 7% MA + 0.2% cetrimide (CTR) and 2% CHX + 0.2% CTR, in four time periods. Study Design: Four specimens per tooth were obtained from a 2-mm thick slice of the cervical third of the root of ten human incisors. At 1, 2, 3 and 5 minutes of immersion, the concentrations of Ca2+ were measured by atomic absorption spectrophotometry. The results were analyzed using the Mann-Whitney U-test. Results: Statistically significant differences were seen for the extracted calcium in all time periods. The amount of calcium extracted by 7% MA was the highest at all fo…
Stan techniczny i wykorzystanie zabudowań po klasztorach skasowanych w guberni wołyńskiej w latach 1832–1853 w świetle raportu wołyńskiego gubernator…
2019
W trakcie XIX-wiecznych kasat klasztorów na obszarze cesarstwa rosyjskiego względy ekonomiczne stanowił istotny, może najważniejszy, ale niejedyny czynnik, uwzględniany przy podejmowaniu decyzji o zniesieniu domu zakonnego. Oficjalnie władze rosyjskie głosiły, że cały majątek klasztorny miał być wykorzystany na utrzymanie szkół oraz instytucji opiekuńczych i charytatywnych. W rzeczywistości przejęte ziemskie dobra klasztorne zasiliły skarb publiczny, a mienie z różnych powodów niezbywalne powiększyło majątek, pozostający w dyspozycji władz gubernialnych oraz Cerkwi prawosławnej. Władze długo nie doceniały znaczenia zabudowań poklasztornych. Dla większości z nich nie znaleziono nowego użytko…
Crystallization and Preliminary X-Ray Analysis of Rotavirus Protein VP6
1998
ABSTRACT As a first step to gain insight into the structure of the rotavirus virion at atomic resolution, we report here the expression, purification, and crystallization of recombinant rotavirus protein VP6. This protein has the property of polymerizing in the form of tubular structures in solution which have hindered crystallization thus far. Using a combination of electron microscopy and small-angle X-ray scattering, we found that addition of Ca 2+ at concentrations higher than 100 mM results in depolymerization of the tubes, leading to an essentially monodisperse solution of trimeric VP6 even at high protein concentrations (higher than 10 mg/ml), thereby enabling us to search for crysta…
Découverte des relations dans les réseaux sociaux
2011
In recent years, social network sites exploded in popularity and become an important part of the online activities on the web. This success is related to the various services/functionalities provided by each site (ranging from media sharing, tagging, blogging, and mainly to online social networking) pushing users to subscribe to several sites and consequently to create several social networks for different purposes and contexts (professional, private, etc.). Nevertheless, current tools and sites provide limited functionalities to organize and identify relationship types within and across social networks which is required in several scenarios such as enforcing users’ privacy, and enhancing t…
Cautionnement. Portée de l'engagement de la caution devant garantir les annuités de remboursement des créanciers en cas de défaillance du débiteur ay…
2008
International audience; (Com. 8 juill.2008, pourvoi n° 07-13.274, arrêt n°809 FS-P+B, Fischer c/ Moyrand, ès-qual., D. 2008. AJ. 1991, obs. A. Lienhard, et Chron. C. cass. 2749, spéc. 2751, obs. M.-L. Bélaval)
Déclaration et vérification des créances. Déclaration dans la deuxième procédure ouverte à la suite de la résolution du plan de redressement
2017
International audience; (Com. 4 mai 2017, n° 15-15.390, arrêt n° 642 F-P+B+I, M. Alain A. c/ Sté UHR Limited et Me Aubert, ès.qual., D. 2017. 975, et les obs. ; Gaz. Pal. 27 juin 2017, p. 58, note P.-M. Le Corre ; RJDA 2017, n° 481)