Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2020 ( 7 )

2019 ( 858 )

2018 ( 1081 )

2017 ( 1099 )

Custom range...

Search Results: 1 - 10 of 624033 matches for " M. S. CORSINI "
All listed articles are free for downloading (OA Articles)
Page 1 /624033
Display every page Item
Altera § μes oxidativas em 3leos de algod £o, girassol e palma utilizados em frituras de mandioca palito congelada
Alimentos e Nutri??o , 2008,
Abstract: O presente trabalho teve como objetivo avaliar as altera § μes oxidativas produzidas nos 3leos de algod £o, girassol e palma, durante o processo de fritura descont -nua de mandioca palito congelada. As frituras foram conduzidas em uma fritadeira el trica dom stica, onde o 3leo foi aquecido, temperatura de 180 °C, por 25 horas, com reposi § £o de 3leo fresco. Os resultados obtidos das determina § μes anal -ticas foram submetidos s an lises de vari ¢ncia, em esquema fatorial, no delineamento inteiramente casualizado, de modo a determinar a influ ancia dos fatores 3leos e tempos de fritura sobre as altera § μes nos 3leos e no produto. Os resultados mostraram que as menores altera § μes ocorreram para o 3leo de palma, mais saturado. Para os 3leos de algod £o e girassol, mais insaturados, verificou-se que ao longo dos tempos de frituras ocorreu um aumento da forma § £o dos compostos de degrada § £o e diminuiu a estabilidade oxidativa. Apesar das diferen §as na composi § £o em cidos graxos, os 3leos estudados n £o apresentaram, em nenhuma an lise, valores acima dos limites recomendados, independentemente do tempo de aquecimento. PALAVRAS-CHAVE: “leos vegetais; altera § μes oxidativas; estabilidade oxidativa; frituras.
On the Correlations between Galaxy Properties and Supermassive Black Hole Mass
A. Beifiori,S. Courteau,E. M. Corsini,Y. Zhu
Physics , 2011, DOI: 10.1111/j.1365-2966.2011.19903.x
Abstract: We use a large sample of upper limits and accurate estimates of supermassive black holes masses coupled with libraries of host galaxy velocity dispersions, rotational velocities and photometric parameters extracted from Sloan Digital Sky Survey i-band images to establish correlations between the SMBH and host galaxy parameters. We test whether the mass of the black hole, MBH, is fundamentally driven by either local or global galaxy properties. We explore correlations between MBH and stellar velocity dispersion sigma, bulge luminosity, bulge mass Sersic index, bulge mean effective surface brightness, luminosity of the galaxy, galaxy stellar mass, maximum circular velocity Vc, galaxy dynamical and effective masses. We verify the tightness of the MBH-sigma relation and find that correlations with other galaxy parameters do not yield tighter trends. We do not find differences in the MBH-sigma relation of barred and unbarred galaxies. The MBH-sigma relation of pseudo-bulges is also coarser and has a different slope than that involving classical bulges. The MBH-bulge mass is not as tight as the MBH-sigma relation, despite the bulge mass proving to be a better proxy of MBH than bulge luminosity. We find a rather poor correlation between MBH and Sersic index suggesting that MBH is not related to the bulge light concentration. The correlations between MBH and galaxy luminosity or mass are not a marked improvement over the MBH sigma relation. If Vc is a proxy for the dark matter halo mass, the large scatter of the MBH-Vc relation then suggests that MBH is more coupled to the baryonic rather than the dark matter. We have tested the need for a third parameter in the MBH scaling relations, through various linear correlations with bulge and galaxy parameters, only to confirm that the fundamental plane of the SMBH is mainly driven by sigma, with a small tilt due to the effective radius. (Abridged)
Disk Galaxies and Galaxy Disks
J. G. Funes S. J,E. M. Corsini
Physics , 2000, DOI: 10.1086/317703
Abstract: The conference Galaxy Disks and Disk Galaxies, sponsored by the Vatican Observatory, was held in June 12-16, 2000 at the Pontifical Gregorian University, in Rome (Italy). The meeting hosted about 230 participants coming from 30 countries. The very full program consisted of 29 review papers, 34 invited talks, and more than 180 posters. The meeting covered topics regarding the structure, formation and evolution of galaxies with disks. Particular attention was dedicated to the stellar and gaseous disk of the Milky Way, the global characteristics of galaxy disks, their structure, morphology and dynamics, the gaseous components, star formation, and chemical evolution, the interactions, accretion, mergers and starbursts, the dark and luminous matter, the establishment of the scaling laws, and the formation and evolution of disk galaxies from a theoretical and observational point of view.
The Circumnuclear Ring of Ionized Gas in NGC3593
E. M. Corsini,A. Pizzella,J. G. Funes S. J.,J. C. Vega Beltran,F. Bertola
Physics , 1998,
Abstract: We present the results of narrow-band Halpha+NII imaging of the early-type spiral NGC3593 in combination with a study of the flux radial profiles of the NII (lambda: 654.80, 658.34 nm), Halpha, and SII (lambda: 671.65, 673.08 nm) emission lines along its major axis. The galaxy is known to contain two counterrotating stellar discs of different size and luminosity. We find that the Halpha emission mainly derives from a small central region of 57 arcsec x 25 arcsec. It consists of a filamentary pattern with a central ring. This has a diameter of about 17 arcsec (~ 0.6/h kpc) and it contributes about half of the total Halpha flux. The ring is interpreted as the result of the interaction between the acquired retrograde gas which later formed the smaller counterrotating stellar disc and the pre-existing prograde gas of the galaxy.
Further evidence for large central mass-to-light ratios in early-type galaxies: the case of ellipticals and lenticulars in the Abell~262 cluster
G. A. Wegner,E. M. Corsini,J. Thomas,R. P. Saglia,R. Bender,S. B. Pu
Physics , 2012, DOI: 10.1088/0004-6256/144/3/78
Abstract: We present radially resolved spectroscopy of 8 early-type galaxies in Abell~262, measuring rotation, velocity dispersion, $H_3$ and $H_4$ coefficients along three axes, and line-strength index profiles of Mg, Fe and H$\beta$. Ionized-gas velocity and velocity dispersion is included for 6 galaxies. We derive dynamical mass-to-light ratios and dark matter densities from orbit-based dynamical models, complemented by the galaxies' ages, metallicities, and $\alpha$-elements abundances. Four galaxies have significant dark matter with halos about 10 times denser than in spirals of the same stellar mass. Using dark matter densities and cosmological simulations, assembly redshifts $\zdm\approx 1-3$, which we found earlier for Coma. The dynamical mass following the light is larger than expected for a Kroupa stellar IMF, especially in galaxies with high velocity dispersion $\sigeff$ inside the effective radius $\reff$. This could indicate a `massive' IMF in massive galaxies. Alternatively, some dark matter in massive galaxies could follow the light closely. Combining with our comparison sample of Coma early-types, we now have 5 of 24 galaxies where (1) mass follows light to $1-3\,\reff$, (2) the dynamical mass-to-light ratio {of all the mass that follows the light is large ($\approx\,8-10$ in the Kron-Cousins $R$ band), (3) the dark matter fraction is negligible to $1-3\,\reff$. Unless the IMF in these galaxies is particularly `massive' and somehow coupled to the dark matter content, there seems a significant degeneracy between luminous and dark matter in some early-type galaxies. The role of violent relaxation is briefly discussed.
Further evidence for large central mass-to-light ratios in massive early-type galaxies
E. M. Corsini,G. A. Wegner,J. Thomas,R. P. Saglia,R. Bender,S. B. Pu
Physics , 2012, DOI: 10.1017/S1743921313004833
Abstract: We studied the stellar populations, distribution of dark matter, and dynamical structure of a sample of 25 early-type galaxies in the Coma and Abell 262 clusters. We derived dynamical mass-to-light ratios and dark matter densities from orbit-based dynamical models, complemented by the ages, metallicities, and \alpha-elements abundances of the galaxies from single stellar population models. Most of the galaxies have a significant detection of dark matter and their halos are about 10 times denser than in spirals of the same stellar mass. Calibrating dark matter densities to cosmological simulations we find assembly redshifts z_{DM} \approx 1-3. The dynamical mass that follows the light is larger than expected for a Kroupa stellar initial mass function, especially in galaxies with high velocity dispersion \sigma_{eff} inside the effective radius r_{eff}. We now have 5 of 25 galaxies where mass follows light to 1-3 r_{eff}, the dynamical mass-to-light ratio of all the mass that follows the light is large (\approx 8-10 in the Kron-Cousins R band), the dark matter fraction is negligible to 1-3 r_{eff}. This could indicate a "massive" initial mass function in massive early-type galaxies. Alternatively, some of the dark matter in massive galaxies could follow the light very closely suggesting a significant degeneracy between luminous and dark matter.
NGC 4672: a new case of an early-type disk galaxy with an orthogonally decoupled core
M. Sarzi,E. M. Corsini,A. Pizzella,J. C. Vega Beltran,M. Cappellari,J. G. Funes S. J.,F. Bertola
Physics , 2000,
Abstract: We report the case of the early-type disk galaxy NGC 4672 as a new example of a galaxy characterized by the orthogonal geometrical decoupling between bulge and disk. The morphological features of this galaxy are discussed as well as the velocity curves and velocity dispersion profiles of stars and ionized gas along both its major and minor axis. We conclude that NGC 4672 has structural (i.e., a bulge elongated perpendicularly to the disk) and kinematical (i.e., a stellar core rotating perpendicularly to the disk) properties similar to those of the Sa NGC 4698. The presence of the isolated core suggests that the disk component is the end result of the acquisition of external material in polar orbits around a pre-existing oblate spheroid as in the case of the ring component of AM 2020-504, the prototype of polar ring ellipticals.
Direct measurements of bar pattern speeds
E. M. Corsini
Physics , 2010,
Abstract: The dynamics of a barred galaxy depends on the angular velocity or pattern speed of its bar. Indeed, it is related to the location of corotation where gravitational and centrifugal forces cancel out in the rest frame of the bar. The only direct method for measuring the bar pattern speed is the Tremaine-Weinberg technique. This method is best suited to the analysis of the distribution and kinematics of the stellar component in absence of significant star formation and patchy dust obscuration. Therefore, it has been mostly used for early-type barred galaxies. The main sources of uncertainties on the directly-measured bar pattern speeds are discussed. There are attempts to overcome the selection bias of the current sample of direct measurements by extending the application of the Tremaine-Weinberg method to the gaseous component. Furthermore, there is a variety of indirect methods which are based on the analysis of the gas distribution and kinematics. They have been largely used to measure the bar pattern speed in late-type barred galaxies. Nearly all the bars measured with direct and indirect methods end close to their corotation radius, i.e., they are as rapidly rotating as they can be.
Counter-Rotation in Disk Galaxies
E. M. Corsini
Physics , 2014,
Abstract: Counter-rotating galaxies host two components rotating in opposite directions with respect to each other. The kinematic and morphological properties of lenticulars and spirals hosting counter-rotating components are reviewed. Statistics of the counter-rotating galaxies and analysis of their stellar populations provide constraints on the formation scenarios which include both environmental and internal processes.
Small-sized Dichroic Atomic Vapor Laser Lock (DAVLL)
Changmin Lee,G. Z. Iwata,E. Corsini,J. M. Higbie,S. Knappe,M. P. Ledbetter,D. Budker
Physics , 2010, DOI: 10.1063/1.3568824
Abstract: Two, lightweight diode laser frequency stabilization systems designed for experiments in the field are described. A significant reduction in size and weight in both models supports the further miniaturization of measurement devices in the field. Similar to a previous design, magnetic-field lines are contained within a magnetic shield enclosing permanent magnets and a Rb cell, so that these DAVLL systems may be used for magnetically sensitive instruments. The Mini-DAVLL system (49 mm long) uses a vapor cell (20 mm long), and does not require cell heaters. An even smaller Micro-DAVLL system (9mm long) uses a micro-fabricated cell (3 mm square), and requires heaters. These new systems show no degradation in performance with regard to previous designs, while considerably reducing dimensions.
Page 1 /624033
Display every page Item

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