Search results for "Roca"
showing 10 items of 1893 documents
Critical analysis of the spin-rotation constants of CF2 and CCl2: A theoretical investigation
2005
Quantum chemical ab initio calculations for the spin-rotation constants of difluorocarbene (CF2) and dichlorocarbene (CCl2) were carried out using coupled-cluster techniques with sequences of correlation-consistent basis sets. Theoretical best estimates were obtained using extrapolation to the complete basis-set limit and taking into account corrections for core correlation, additional diffuse functions and zero-point vibrational effects. It is demonstrated that such accurate theoretical estimates can be used either to support or to challenge the analysis of the experimental spectra and the reliability of the resulting data. 2005 Elsevier B.V. All rights reserved.
Electro- and Photo-driven Reduction of CO 2 by a trans -(Cl)-[Os(diimine)(CO) 2 Cl 2 ] Precursor Catalyst: Influence of the Diimine Substituent and A…
2016
A series of [OsII(NN)(CO)2Cl2] complexes where NN is a 2,2′-bipyridine ligand substituted in the 4,4′ positions by H (C1), CH3 (C2), C(CH3)3 (C3), or C(O)OCH(CH3)2 (C4) has been studied as catalysts for the reduction of CO2. Electrocatalysis shows that the selectivity of the reaction can be switched toward the production of CO or HCOO− with an electron-donating (C2, C3) or -withdrawing (C4) substituent, respectively. The electrocatalytic process is a result of the formation of an Os0-bonded polymer, which was characterized by electrochemistry, UV/Visible and EPR spectroscopies. Photolysis of the complexes under CO2 in DMF+TEOA produces CO as a major product with a remarkably stable turnover…
Semi-compatible and reciprocally continuous maps in weak non-Archimedean Menger PM-spaces
2012
In this paper, we introduce semi-compatible maps and reciprocally continuous maps in weak non-Archimedean PM-spaces and establish a common fixed point theorem for such maps. Moreover, we show that, in the context of reciprocal continuity, the notions of compatibility and semi-compatibility of maps become equivalent. Our result generalizes several fixed point theorems in the sense that all maps involved in the theorem can be discontinuous even at the common fixed point.
Multialternating graded polynomials and growth of polynomial identities
2012
Let G be a finite group and A a finite dimensional G-graded algebra over a field of characteristic zero. When A is simple as a G-graded algebra, by mean of Regev central polynomials we construct multialternating graded polynomials of arbitrarily large degree non vanishing on A. As a consequence we compute the exponential rate of growth of the sequence of graded codimensions of an arbitrary G-graded algebra satisfying an ordinary polynomial identity. In particular we show it is an integer. The result was proviously known in case G is abelian.
Polynomial Identities and Asymptotic Methods
2005
Polynomial identities and PI-algebras $S_n$-representations Group gradings and group actions Codimension and colength growth Matrix invariants and central polynomials The PI-exponent of an algebra Polynomial growth and low PI-exponent Classifying minimal varieties Computing the exponent of a polynomial $G$-identities and $G\wr S_n$-action Superalgebras, *-algebras and codimension growth Lie algebras and nonassociative algebras The generalized-six-square theorem Bibliography Index.
The maximal coefficient of ternary cyclotomic polynomials with one free prime
2014
A cyclotomic polynomial Φn(x) is said to be ternary if n = pqr, with p, q and r distinct odd primes. Let M(p, q) be the maximum (in absolute value) coefficient appearing in the polynomial family Φpqr(x) with p < q < r, p and q fixed. Here a stronger version of the main conjecture of Gallot, Moree and Wilms regarding M(p, q) is established. Furthermore it is shown that there is an algorithm to compute M(p): = max {M(p, q): q > p}. Our methods are the most geometric used so far in the study of ternary cyclotomic polynomials.
Some Integral Type Fixed-Point Theorems and an Application to Systems of Functional Equations
2013
In this paper, we prove a new common fixed point theorem for four self mappings by using the notions of compatibility and subsequential continuity (alternate subcompatibility and reciprocal continuity) in metric spaces satisfying a general contractive condition of integral type. We give some examples to support the useability of our main result. Also, we obtain some fixed point theorems of Gregus type for four mappings satisfying a strict general contractive condition of integral type in metric spaces. We conclude the paper with an application of our main result to solvability of systems of functional equations.
Automated detection and localization system of myocardial infarction in single-beat ECG using Dual-Q TQWT and wavelet packet tensor decomposition.
2019
Abstract Background and objective It is challenging to conduct real-time identification of myocardial infarction (MI) due to artifact corruption and high dimensionality of multi-lead electrocardiogram (ECG). In the present study, we proposed an automated single-beat MI detection and localization system using dual-Q tunable Q-factor wavelet transformation (Dual-Q TQWT) denoising algorithm. Methods After denoising and segmentation of ECG, a fourth-order wavelet tensor (leads × subbands × samples × beats) was constructed based on the discrete wavelet packet transform (DWPT), to represent the features considering the information of inter-beat, intra-beat, inter-frequency, and inter-lead. To red…
El monasterio jerónimo de Santa María de la Murta (Valencia)
1995
El edificio se levantó sobre el solar que ocupaban las ermitas de San Jerónimo, Nuestra Señora y San Miguel y según Sigüenza era de reducido tamaño. "Edificose la casa entre las peñas de aquel valle, tan pequeña como agora se vee, aunque trapda con tan buen ingenio, que pone en admiracion a los que la veen por lo de fuera, y de repente, no pudiendo entender como en tan pequeño edificio y casa puede aver cumplimiento de casa de San Geronimo, claustro, celdas, dormitorio, refetorio, y otras oficinas, y ay todo esto tan bueno, que es de lo bueno".