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51.
52.
Inside Cover: Advances on the Determination of the Astatine Pourbaix Diagram: Predomination of AtO(OH)2− over At− in Basic Conditions (Chem. Eur. J. 9/2016) 下载免费PDF全文
Dumitru‐Claudiu Sergentu Dr. David Teze Dr. Andréa Sabatié‐Gogova Dr. Cyrille Alliot Ning Guo Dr. Fadel Bassal Dr. Isidro Da Silva Prof. Dr. David Deniaud Dr. Rémi Maurice Dr. Julie Champion Dr. Nicolas Galland Dr. Gilles Montavon 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(9):2834-2834
53.
Borges KB Sánchez AJ Pupo MT Bonato PS Collado IG 《Journal of AOAC International》2010,93(6):1811-1820
A method was optimized for the analysis of omeprazole (OMZ) by ultra-high speed LC with diode array detection using a monolithic Chromolith Fast Gradient RP 18 endcapped column (50 x 2.0 mm id). The analyses were performed at 30 degrees C using a mobile phase consisting of 0.15% (v/v) trifluoroacetic acid (TFA) in water (solvent A) and 0.15% (v/v) TFA in acetonitrile (solvent B) under a linear gradient of 5 to 90% B in 1 min at a flow rate of 1.0 mL/min and detection at 220 nm. Under these conditions, OMZ retention time was approximately 0.74 min. Validation parameters, such as selectivity, linearity, precision, accuracy, and robustness, showed results within the acceptable criteria. The method developed was successfully applied to OMZ enteric-coated pellets, showing that this assay can be used in the pharmaceutical industry for routine QC analysis. Moreover, the analytical conditions established allow for the simultaneous analysis of OMZ metabolites, 5-hydroxyomeprazole and omeprazole sulfone, in the same run, showing that this method can be extended to other matrixes with adequate procedures for sample preparation. 相似文献
54.
Isidro Humberto Munive 《Potential Analysis》2012,37(4):333-352
We prove Fatou type theorems for solutions of the heat equation in sub-Riemannian spaces. The doubling property of L-caloric measure, the Dahlberg estimate, the local comparison theorem, among other results, are established here. A backward Harnack inequality is proved for non-negative solutions vanishing in the lateral boundary. 相似文献
55.
Isidro H. Munive 《manuscripta mathematica》2012,138(3-4):299-313
In this note we generalize A. Grigor’yan’s volume test for the stochastic completeness of a Riemannian manifold to a sub-Riemannian setting. As an application of this result, and of a new estimate of the growth of the volume of the metric balls at infinity, we give a different proof of (and extend) a theorem in Baudoin and Garofalo (Arxiv preprint, submitted paper, 2009) stating that when a smooth, complete and connected manifold satisfies the generalized curvature-dimension inequality introduced in that paper, then the manifold turns out to be stochastically complete. 相似文献
56.
Manuel Ferná ndez Isidro Palacios 《Proceedings of the American Mathematical Society》1997,125(5):1323-1328
A formula is given for the directional uniform rotundity modulus of , where is a normed space. Then a necessary and sufficient condition is provided for to be uniformly rotund in a direction.
57.
Mariano Matilla-García Isidro Morales Jose Miguel Rodríguez Manuel Ruiz Marín 《Entropy (Basel, Switzerland)》2021,23(2)
The modeling and prediction of chaotic time series require proper reconstruction of the state space from the available data in order to successfully estimate invariant properties of the embedded attractor. Thus, one must choose appropriate time delay and embedding dimension p for phase space reconstruction. The value of can be estimated from the Mutual Information, but this method is rather cumbersome computationally. Additionally, some researchers have recommended that should be chosen to be dependent on the embedding dimension p by means of an appropriate value for the time delay , which is the optimal time delay for independence of the time series. The C-C method, based on Correlation Integral, is a method simpler than Mutual Information and has been proposed to select optimally and . In this paper, we suggest a simple method for estimating and based on symbolic analysis and symbolic entropy. As in the C-C method, is estimated as the first local optimal time delay and as the time delay for independence of the time series. The method is applied to several chaotic time series that are the base of comparison for several techniques. The numerical simulations for these systems verify that the proposed symbolic-based method is useful for practitioners and, according to the studied models, has a better performance than the C-C method for the choice of the time delay and embedding dimension. In addition, the method is applied to EEG data in order to study and compare some dynamic characteristics of brain activity under epileptic episodes 相似文献
58.
A thermodynamic approach based on both the classical Flory-Huggins (FH) formalism and the association equilibria (AE) theory has been developed to study the solubility properties of a system formed by a proton-donor solvent (A), a proton-acceptor solvent (B) and a proton-acceptor polymer (C). The miscibility of this ternary system is attained by competitive specific interactions via hydrogen-bonding established between the hydroxyl and carbonyl interacting groups of either solvent-solvent (AB) or solvent-polymer (AC) system components. The binary AB and AC specific interactions and their dependence with the system composition as well as with the extent of the association equilibrium have been quantified by means of two new parameters, ΔgAB and ΔgAC. These excess functions have appeared to be equivalent to the combinatorial or entropic term of the Gibbs free energy of the complex formation process, which accounts for the entropy of mixing plus the intermolecular specific interactions. The theoretical predictions have reasonablely agreed with experimental data on preferential solvation of two systems taken from literature: methanol(A)/1,4-dioxane(B)/poly(alkyl methacrylate)(C) and n-alcohol(A)/heptan-3-one(B)/poly(vinyl pyrrolidone)(C). 相似文献
59.
60.
Veloso A Fernández R Astigarraga E Barreda-Gómez G Manuel I Giralt MT Ferrer I Ochoa B Rodríguez-Puertas R Fernández JA 《Analytical and bioanalytical chemistry》2011,401(1):89-101
The enormous abundance of lipid molecules in the central nervous system (CNS) suggests that their role is not limited to be
structural and energetic components of cells. Over the last decades, some lipids in the CNS have been identified as intracellular
signalers, while others are known to act as neuromodulators of neurotransmission through binding to specific receptors. Neurotransmitters
of lipidic nature, currently known as neurolipids, are synthesized during the metabolism of phospholipid precursors present
in cell membranes. Therefore, the anatomical identification of each of the different lipid species in human CNS by imaging
mass spectrometry (IMS), in association with other biochemical techniques with spatial resolution, can increase our knowledge
on the precise metabolic routes that synthesize these neurolipids and their localization. The present study shows the lipid
distribution obtained by MALDI-TOF IMS in human frontal cortex, hippocampus, and striatal area, together with functional autoradiography
of cannabinoid and LPA receptors. The combined application of these methods to postmortem human brain samples may be envisioned
as critical to further understand neurological diseases, in general, and particularly, the neurodegeneration that accompanies
Alzheimer’s disease. 相似文献