oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2020 ( 2 )

2019 ( 193 )

2018 ( 254 )

2017 ( 276 )

Custom range...

Search Results: 1 - 10 of 194213 matches for " G. Gonzalez "
All listed articles are free for downloading (OA Articles)
Page 1 /194213
Display every page Item
Lagrangians and Hamiltonians for one-dimensional systems
G. Gonzalez
Physics , 2004, DOI: 10.1023/B:IJTP.0000048998.57747.99
Abstract: An equation is obtained to find the Lagrangian for a one-dimensional autonomous system. The continuity of the first derivative of its constant of motion is assumed. This equation is solved for a generic nonconservative autonomous system that has certain quasi-relativistic properties. A new method based on a Taylor series expansion is used to obtain the associated Hamiltonian for this system. These results have the usual expression for a conservative system when the dissipation parameter goes to zero. An example of this approach is given.
Relativistic motion with linear dissipation
G. Gonzalez
Physics , 2005,
Abstract: A general formalism for obtaining the Lagrangian and Hamiltonian for a one dimensional dissipative system is developed. The formalism is illustrated by applying it to the case of a relativistic particle with linear dissipation. The relativistic wave equation is solved for a free particle with linear dissipation.
Hamilton-Jacobi theory for one dimensional autonomous systems using parametric transformations
G. Gonzalez
Mathematics , 2005,
Abstract: A necessary and sufficient condition for a parameter transformation that leaves invariant the energy of a one dimensional autonomous system is obtained. Using a parameter transformation the Hamilton-Jacobi equation is solved by a quadrature. An example of this approach is given.
Effects on the eigenvalues of the quantum bouncer due to dissipation
G. Lopez,G. Gonzalez
Physics , 2003,
Abstract: Effects on the spectra of the quantum bouncer due to dissipation are given when a linear or quadratic dissipation is taken into account. Classical constant of motions and Hamiltonians are deduced for these systems and their quantized eigenvalues are estimated through perturbation theory. we found some differences when we compare the eigenvalues of these two quantities.
Susceptibilidad de Vasconcellea cauliflora al virus de la mancha anillada de la lechosa
Gonzalez,A; Trujillo,G;
Revista de la Facultad de Agronomía , 2005,
Abstract: this work demonstrated the susceptibility of vasconcellea cauliflora, a species considered as virus resistant to papaya ringspot virus (prsv-p). disease transmission by mechanical inoculation of prsv-p severe strain on 60 days old plants was corroborated. under greenhouse conditions with average values of 25.15oc and 78.68% rh, 8.3% of plants inoculated with the severe strain showed apical necrosis. at the facultad de agronomía (ucv), maracay (440 msnm) under field conditions, 8.6% of inoculated plants showed typical symptoms of the disease seven days after beings transplanted. subsequently, an inoculation test was done in three growth chamber conditions: t1=29oc and 6300 lux; t2= 27oc and 5500 lux and t3= 25oc and 4200 lux; the daily time was fixed at 16 h, and the relative humidity was about 75.5% on average. systemic symptoms were observed in 82, 86 and 47% of plants in treatments t1, t2 y t3 respectively. these results were consistent with the elisa test. the susceptibility of v. cauliflora to the local severe strain of prsv-p was influenced by temperature and light intensity conditions. this questions the role of this species in search for prsv-p resistance genes in papaya breeding programs.
Susceptibilidad de Vasconcellea cauliflora al virus de la mancha anillada de la lechosa Susceptibility of Vasconcellea cauliflora to Papaya ringspot virus
A Gonzalez,G Trujillo
Revista de la Facultad de Agronomía , 2005,
Abstract: Esta investigación demostró la susceptibilidad de Vasconcellea cauliflora, especie que ha sido considerada como resistente al virus de la mancha anillada de la lechosa (PRSV-P). La transmisión de la enfermedad se logró mediante la inoculación mecánica de una cepa severa del PRSV-P en plantas de 60 días de edad. Estas evidenciaron síntomas de necrosis del cogollo en 8,3% bajo condiciones de invernadero a 25,15oC y 78,68% HR promedio. Bajo condiciones de campo en la Facultad de Agronomía (UCV), Maracay (440 msnm), se contabilizó el 8,6% de plantas inoculadas con síntomas típicos de la enfermedad a los siete días del trasplante. Posteriormente se realizó un ensayo bajo condiciones controladas en cámara de crecimiento. Las plantas inoculadas fueron expuestas a tres tratamientos de temperatura e intensidad lumínica: T1= 29oC y 6300 lux; T2= 27oC y 5500 lux y T3= 25oC y 4200 lux; con fotoperiodo de 16 horas de luz y 75,5% HR promedio. Los resultados demostraron la transmisión del PRSV-P en 82, 86 y 47% respectivamente; la sintomatología viral se corroboró mediante el uso de ELISA. Estos resultados cuestionan el uso de esta especie como fuente de genes de resistencia al PRSV-P en los programas de mejoramiento de lechosa. This work demonstrated the susceptibility of Vasconcellea cauliflora, a species considered as virus resistant to Papaya ringspot virus (PRSV-P). Disease transmission by mechanical inoculation of PRSV-P severe strain on 60 days old plants was corroborated. Under greenhouse conditions with average values of 25.15oC and 78.68% RH, 8.3% of plants inoculated with the severe strain showed apical necrosis. At the Facultad de Agronomía (UCV), Maracay (440 msnm) under field conditions, 8.6% of inoculated plants showed typical symptoms of the disease seven days after beings transplanted. Subsequently, an inoculation test was done in three growth chamber conditions: T1=29oC and 6300 lux; T2= 27oC and 5500 lux and T3= 25oC and 4200 lux; the daily time was fixed at 16 h, and the relative humidity was about 75.5% on average. Systemic symptoms were observed in 82, 86 and 47% of plants in treatments T1, T2 y T3 respectively. These results were consistent with the ELISA test. The susceptibility of V. cauliflora to the local severe strain of PRSV-P was influenced by temperature and light intensity conditions. This questions the role of this species in search for PRSV-P resistance genes in papaya breeding programs.
EL CONSENSO SOBRE LA RACIONALIDAD ECONóMICA?
Natalia Gonzalez Gómez
Estudios Gerenciales , 2000,
Abstract: Este artículo examina la robustez que sostiene el núcleo teórico ortodoxo, más específicamente, los supuestos de información y racionalidad perfectas. Se hace alusión a un modelo de toma de decisiones bajo racionalidad acotada y perfecta información como alternativa teórica.
Regularized perturbative series for the ionization potential of atomic ions
G. Gil,A. Gonzalez
Physics , 2013,
Abstract: We study $N$-electron atoms with nuclear charge $Z$. It is well known that, in the cationic ($Z > N$) high-$Z$ region, the atom behaves as a weakly interacting system. The anionic ($Z < N$) regime, on the other hand, is characterized by an instability threshold at $Z_c \lesssim N-1$, below which the atom spontaneously emits an electron. We construct a regularized perturbative series (RPS) for the ionization potential of ions in an isoelectronic sequence that exactly reproduces both, the large $Z$ and the $Z$ near $Z_c$ limits. The large-$Z$ expansion coefficients are analytically computed from perturbation theory, whereas the slope of the energy curve at $Z=N-1$ is computed from a kind of zero-range forces theory that uses as input the electron affinity and the covalent radius of the neutral atom with $N-1$ electrons. Relativistic effects, at the level of first-order perturbation theory, are considered. Our RPS formula is to be used in order to check the consistency of the ionization potential values for atomic ions contained in the NIST database.
Stability of atoms in the anionic domain (Z
G. Gil,A. Gonzalez
Physics , 2013,
Abstract: We study the stability and universal behaviour of the ionization energy of N-electron atoms with nuclear charge Z in the anionic domain (Z
Parent Stars of Extrasolar Planets V: HD75289
G. Gonzalez,C. Laws
Physics , 1999, DOI: 10.1086/301176
Abstract: The results of a new spectroscopic analysis of HD75289, recently reported to harbor a Jovian-mass planet, are presented. From high-resolution, high-S/N ratio spectra, we derive [Fe/H] = +0.28 +/- 0.05 for this star, in agreement with the spectroscopic study of Gratton et al., published 10 years ago. In addition, we present a re-analysis of the spectra of Upsilon And and Tau Boo; our new parameters for these two stars are now in better agreement with photometrically-derived values and with the recent spectroscopic analyses of Fuhrmann, et al. We also report on extended abundance analyses of 14 Her, HD187123, HD210277, and Rho Cnc. If we include the recent spectroscopic analyses of HD217107 by Randich et al. and Sadakane et al., who both reported [Fe/H] ~ +0.30 for this star, we can state that all the "hot-Jupiter" systems studied to date have metal-rich parent stars. We find that the mean [C/Fe] and [Na/Fe] values among the stars-with-planets sample are smaller than the corresponding quantities among field stars of the same [Fe/H].
Page 1 /194213
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.