Search results for "Solution"

Anomalies in the temperature dependence of the 1.2-? absorption of liquid water

1975

The weakly absorbed 1.2-μ combination band of water was accurately studied as a function of temperature, in both its profile and first derivative, to obtain information on the bulk properties of liquid water. Arrhenius plots of integrated component intensity ratios showed well aligned experimental points, except for a neatly defined break occurring in the 30 to 40°C temperature interval for pure water A similar break, shifted by some 18°C towards lower temperature, was found in the case of 1M NaClO4 aqueous solutions. The breaks are tentatively assumed to result from abrupt though subtle changes involving low-frequency modes. This tentative, assumption appears independent of specific models…

1989

The reaction kinetics for the group transfer polymerization (GTP) of tert-butyl methacrylate (TBMA) using a silyl ketene acetal initiator and a nucleophilic catalyst are investigated. The reaction is shown to be of first order in both monomer and catalyst concentrations. The “livingness” of this system appears to be influenced by the reaction temperature. At temperatures above −20°C, deactivation is observed, with its severity increasing with increasing temperature. This deactivation is attributed to a depletion of catalyst by side reactions. It was demonstrated that reactivation is made possible by the addition of more catalyst. This result is in contrast to the anionic polymerization of T…

The Electrical Properties of Ba1-ySryZrxTi1-xO3Solid Solution

2011

A lead-free solid solution Ba0.80Sr0.20Ti0.75Zr0.25O3 was prepared by a conventional technology. The structure and morphology of investgated samples were characterised by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The studies of electric conductivity were performed depending on temperature and frequency of electric measuring field. The activation energy was calculated from the Arrhenius plots.

Speciation and oxidation kinetics of arsenic in the thermal springs of Wiesbaden spa, Germany.

2001

Since 1886 arsenic has been known to be present as a trace component in the Wiesbaden thermal waters at concentrations of over 100 microg L(-1). In this study for the first time molecular level speciation of arsenic was measured both in the water (by HG-AAS) and in wellstone scale deposits (by XANES). Most of the arsenic in the anoxic NaCl-type waters is in the reduced arsenite form. Hydrous ferric oxide (HFO) precipitates in the scale deposits scavenge only the minor dissolved arsenate portion which is, however, accumulated up to 3% w/w. Isothermal precipitation experiments at in-situ temperatures showed a difference between the progress of both arsenic and iron oxidation and precipitation…

Composition et cognition musicales : création, perception, appréciation

2005

Ce texte est un rapport de fin de recherche issu de l'ACI cognitique.; Ce projet avait pour objet d'apporter des éléments objectifs de réflexion sur les possibilités et limites de la perception et de la compréhension des matériaux et des structures d'une oeuvre de musique contemporaine. Les buts spécifiques comprenaient l'étude : 1) des processus d'invention et de résolution de problèmes dans la composition musicale, 2) des processus de traitement perceptif et de mémorisation des matériaux musicaux, 3) du traitement perceptif et mnésique des variations ou transformations opérées sur ces matériaux et de l'intégration des matériaux et de leurs transformations dans une forme d'ensemble, 4) du …

Stability of impulsive differential systems

2013

The asymptotic phase property and reduction principle for stability of a trivial solution is generalized to the case of the noninvertible impulsive differential equations in Banach spaces whose linear parts split into two parts and satisfy the condition of separation.

Global exponential stability of delayed Markovian jump fuzzy cellular neural networks with generally incomplete transition probability

2014

The problem of global exponential stability in mean square of delayed Markovian jump fuzzy cellular neural networks (DMJFCNNs) with generally uncertain transition rates (GUTRs) is investigated in this paper. In this GUTR neural network model, each transition rate can be completely unknown or only its estimate value is known. This new uncertain model is more general than the existing ones. By constructing suitable Lyapunov functionals, several sufficient conditions on the exponential stability in mean square of its equilibrium solution are derived in terms of linear matrix inequalities (LMIs). Finally, a numerical example is presented to illustrate the effectiveness and efficiency of our res…

Effect of raster resolution and polygon-conversion algorithm on landslide susceptibility mapping

2016

The choice of the proper resolution in landslide susceptibility mapping is a worth considering issue. If, on the one hand, a coarse spatial resolution may describe the terrain morphologic properties with low accuracy, on the other hand, at very fine resolutions, some of the DEM-derived morphometric factors may hold an excess of details. Moreover, the landslide inventory maps are represented throughout geospatial vector data structure, therefore a conversion procedure vector-to-raster is required.This work investigates the effects of raster resolution on the susceptibility mapping in conjunction with the use of different algorithms of vector-raster conversion. The Artificial Neural Network t…

Solutions of the Einstein field equations for a bounded and finite discontinuous source, and its generalization: Metric matching conditions and jumpi…

2019

We consider the metrics of the General Relativity, whose energy-momentum tensor has a bounded support where it is continuous except for a finite step across the corresponding boundary surface. As a consequence, the first derivative of the metric across this boundary could perhaps present a finite step too. However, we can assume that the metric is ${\cal C}^1$ class everywhere. In such a case, although the partial second derivatives of the metric exhibit finite (no Dirac $\delta$ functions) discontinuities, the Dirac $\delta$ functions will still appear in the conservation equation of the energy-momentum tensor. As a consequence, strictly speaking, the corresponding metric solutions of the …

Search for correlations between the arrival directions of IceCube neutrino events and ultrahigh-energy cosmic rays detected by the Pierre Auger Obser…

2016

This paper presents the results of different searches for correlations between very high-energy neutrino candidates detected by IceCube and the highest-energy cosmic rays measured by the Pierre Auger Observatory and the Telescope Array. We first consider samples of cascade neutrino events and of high-energy neutrino-induced muon tracks, which provided evidence for a neutrino flux of astrophysical origin, and study their cross-correlation with the ultrahigh-energy cosmic ray (UHECR) samples as a function of angular separation. We also study their possible directional correlations using a likelihood method stacking the neutrino arrival directions and adopting different assumptions on the size…