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La conexión Levantino-Chipriota. Indicios de comercio Atlántico con el Mediterráneo Oriental durante el Bronce Final (1150-950 a.C.)
Mederos Martín, Alfredo
Trabajos de Prehistoria , 1996,
Abstract: Starting from an analysis of the trade and the chronological sequence between the Iberian Peninsula and the Cypro-Philistinian area during part of the Late Bronze Age (1150-950 BC), we can recognize, in the most peripheral territories of the Eastern Mediterranean, the presence at least of some exports of manufactured products in the form of articulated spits and knobbed fibulas of the Huelva type, and imports of bronze bowls. These artefacts appear in small hoards (Berzocana, Spain) or in tombs (Amathus, Cyprus), associated with members of the leading elites. This suggests an exchange of gifts in order to establish trade ties. We also evaluate the historic and economical aims of this trade. A partir de un análisis del comercio y de las secuencias cronológicas de la Península Ibérica y el área Chipro-Filistea durante parte del Bronce Final (1150-950 AC), se puede reconocer en los territorios más periféricos del Mediterráneo Oriental, la presencia de, al menos, algunas exportaciones de productos manufacturados como asadores articulados y fíbulas de codo tipo Huelva y de importaciones de vasos metálicos. Dichos productos aparecen en peque os depósitos (Berzocana, Espa a) o enterramientos (Amathus, Chipre) asociados a miembros de las élites dirigentes, insinuando un intercambio de regalos para establecer lazos comerciales. Se evalúan las implicaciones históricas y económicas que incentivaron dicho comercio.
A.C. Conductivity of a Disordered Metal  [PDF]
Girish S. Setlur
Physics , 2003,
Abstract: The degenerate free Fermi gas coupled to a random potential is used to compute a.c. conductivity in various dimensions. We first formally diagonalise the hamiltonian using an appropriate basis that is a functional of the disorder potential. Then we compute the a.c. conductivity at zero temperature using the Kubo formula. This a.c. conductivity is a functional of the disordered potential. The wavefunction of extended states is written as exponential of the logarithm. We use the cumulant expansion to compute the disordered averaged a.c. conductivity for Gaussian disorder. The formula is valid if a certain linearization approximation is valid in the long-wavelength limit.
Moneda ibérica y gens mariana (107-90 a.C.)
López Sánchez, Fernando
Gladius , 2010, DOI: 10.3989/gladius.2010.0009
Abstract: The division between domi/rider reverses with a palm and armed militiae/rider in (Celt)iberian currency leads us to establish a link between certain mints and military camps. An example of this can be found in the Ikale (n) sken denarii, which must be related to the troops sent in the direction of Córdoba by Kese, in support of Sertorius (97-93 B.C.). The Sekobirikes denarii, on the other hand, were the coins used by the troops of Sekaisa while in the territory of the Arevaci with T. Didius and V. Flaccus (98-92 B.C.), and all of the bronze Catalan series corresponds with the start of the Bellum Sociale (90 B.C.). During the second century B.C., Rome waged war in Hispania on the invitation of cities such as Osca, Turiasu or Segeda-Sekaisa, which were threatened by powerful enemies. In the period of Marius the (Celt)iberian armies adopted a Roman approach to warfare. All of the (Celt)iberian currency was minted between the years 107 and 90 B.C., and as such it reflects not the Roman conquest of Hispania, but the formation of a Hispanic branch of the Roman army. La división entre reversos domi/jinete con palma y militiae/jinete armado en la moneda (celt)ibérica permite afi rmar que algunas cecas hispanas se corresponden con campamentos militares. Así, los denarios Ikale(n)sken deben ponerse en relación con las tropas enviadas por Kese hacia Córdoba en apoyo de Sertorio (97-93 a.C.). Los denarios Sekobirikes, por su parte, son las monedas de las tropas de Sekaisa en territorio arévaco con T. Didio y V. Flaco (98-92 a.C.). Las series catalanas en bronce se corresponden todas con el inicio del Bellum Sociale (90 a.C.). Roma luchó en Hispania durante el siglo II a.C. por invitación de ciudades como Segeda-Sekaisa, amenazadas por enemigos demasiado poderosos. Los ejércitos (celt)ibéricos combatían a la romana en tiempos de Mario. La moneda (celt)ibérica clásica fue toda ella acu ada entre los a os 107 y 90 a.C. Refleja, no la conquista romana de Hispania, sino la conformación de una rama hispana del ejército romano. [fr] La représentation des branches de palmiers (domi) et des armes (militiae) sur le type de revers monétaire au cavalier ibérique permet d’affi rmer la relation de certaines frappes monétaires hispaniques avec des campements militaires. Ainsi, les deniers Ikale(n)sken peuvent être mis en relation avec les troupes envoyées par Kese à Cordoue pour venir en aide à Sertorius (97-93 avant J.-C.). Les deniers Sekobirikes sont, de leur c té, les monnaies des cavaliers de Sekaisa installés en terre arévaque par T. Didius et V. Flaccus (98-82 avant J.-C.)
El depósito de armas del bronce final de Los Cascajos , Gra ón (La Rioja)
Alonso Fernández, Carmen,Jiménez Echevarría, Javier
Gladius , 2009, DOI: 10.3989/gladius.2009.214
Abstract: The until now unpublished hoard of weapons from Los Cascajos is exceptional in its geographical context, since it is the only one recovered in the province of La Rioja, and it is also exceptional at the Peninsular level for the pieces that make it up: number, typology, origin and conservation. It’s a set of metal pieces from the transit of the Late Bronze Age I to the Late Bronze Age II (1200-1000 B.C.), some of them unpublished in the Peninsula, since they are not of local manufacture but imported from other territories of the Atlantic Bronze Age. The formal characteristics of some pieces point to the Thames Valley as place of origin, although it is not possible to dismiss the Gallic origin of others. El hasta ahora inédito depósito de armas de Los Cascajos es excepcional dentro de su contexto geográfico, ya que es el único recuperado en la provincia de La Rioja, pero también a nivel peninsular por las piezas que lo integran: por su número, tipología, origen y conservación. Se trata de un conjunto de metales del tránsito del BFI al BFII (1200-1000 a.C.), algunos de ellos inéditos en la Península, ya que no son de factura local, sino importados de otros territorios del Bronce Atlántico. Las características formales de algunas piezas se alan el Valle del Támesis como lugar de procedencia, aunque sin descartar el origen galo de otras.
Discovery of an ultra-cool subdwarf: LSR1425+7102, first star with spectral type sdM8.0  [PDF]
Sebastien Lepine,Michael M. Shara,R. Michael Rich
Physics , 2003, DOI: 10.1086/374210
Abstract: We report the discovery of the coolest subdwarf reported to date. The star LSR1425+7102 was discovered in our survey for faint high proper motion stars in the northern sky. Follow-up spectroscopy revealed the star to be a very red object with the characteristic signature of M subdwarfs: strong CaH bands but relatively weaker TiO bands. The CaH molecular band at $\approx\lambda$6900\AA\ is particularly strong. By extrapolating the empirical relationship between the strength of the CaH molecular band and the subdwarf subtype, we conclude that LSR1425+7102 is the first star to be discovered with spectral type sdM8.0.
Una nueva perspectiva de la Edad del Bronce
Vázquez Varela, J. M.,Cano Pan, J. A.
Trabajos de Prehistoria , 1988,
Abstract: Based on information from excavations in the Late Bronze Age settlement of Portecelo in the North-West of Spain it is suggested a new perspective about the Bronze Age and the Pebble Culture. La presencia de elementos típicos de la Cultura de los cantos tallados en el yacimiento del Bronce Final de Portecelo, Pontevedra, plantea problemas sobre la visión tradicional de la Edad del Bronce y de la Cultura de los cantos tallados . Se propone la elaboración de un modelo interpretativo más amplio para esta época y un uso más critico del término Cultura de los cantos tallados .
Development of Nano-Structured AA1050 by ECAE and Thermal Treatments  [PDF]
Carmelo J. Luis, Javier León, Rodrigo Luri, Ignacio Puertas, Ivan Pérez, Daniel Salcedo
Soft Nanoscience Letters (SNL) , 2011, DOI: 10.4236/snl.2011.14019
Abstract: In this present work, a study regarding the change in the mechanical properties and in the microstructure of the aluminium alloy AA1050 is made after being processed by severe plastic deformation (SPD) with Equal Channel Angular Extrusion (ECAE). Optical and scanning electron microscopy techniques will be employed in order to determine the evolution of the microstructure after different thermal treatments, subsequent to the severe plastic deformation process. This present work involves a profound study on the change in the mechanical properties for an alloy which has a very low value of strain hardening at room temperature. With this, it is demonstrated that it is possible to improve its mechanical properties significantly with an adequate combination of ECAE processing and thermal treatments.
Los primeros objetos de bronce en el occidente de Europa
Fernández-Miranda, Manuel,Montero Ruiz, Ignacio,Rovira Llorens, Salvador
Trabajos de Prehistoria , 1995,
Abstract: The alloy of copper with tin is used to show cultural relations and exchanges between Bronze Age cultures in western and central Europe. At the beginning, the distribution and location of tin resources explains the variations in bronze composition, but interregional ex-change leads later to a more homogeneous alloy. During the Early Bronze Age the Iberian Peninsula was not connected to the exchange networks of western Europe, and the first true bronzes appear at least two centuries la ter. The tin alloy spread over Iberia from north to south, and arrive to South-east at the end of the Middle Brome Age, due to the isolation of this region. A través del uso de la aleación de cobre y esta o en la tecnología metalúrgica de la Edad del Bronce europea se analizan las relaciones culturales e intercambios que tienen lugar entre los diversos grupos culturales. Al principio la disponibilidad de recursos minerales de esta o condicionó la composición de la aleación, pero más tarde el establecimiento de relaciones comerciales condujo a una mayor homogeneización en la producción. La Península Ibérica aparece durante el Bronce Antiguo desconectada de las interacciones actuantes en el Occidente de Europa, acusando un retraso en el conocimiento del bronce de al menos dos siglos. La difusión de la aleación se produce de norte a sur, llegando al Sureste a fines del Bronce Medio como consecuencia de su aislamiento.
Two in one? A possible dual radio-emitting nucleus in the quasar SDSS J1425+3231  [PDF]
S. Frey,Z. Paragi,T. An,K. E. Gabanyi
Physics , 2012, DOI: 10.1111/j.1365-2966.2012.21491.x
Abstract: The radio-emitting quasar SDSS J1425+3231 (z=0.478) was recently found to have double-peaked narrow [O III] optical emission lines. Based on the analysis of the optical spectrum, Peng et al. (2011) suggested that this object harbours a dual active galactic nucleus (AGN) system, with two supermassive black holes (SMBHs) separated on the kpc scale. SMBH pairs should be ubiquitous according to hierarchical galaxy formation scenarios in which the host galaxies and their central black holes grow together via interactions and eventual mergers. Yet the number of presently-confirmed dual SMBHs on kpc or smaller scales remains small. A possible way to obtain direct observational evidence for duality is to conduct high-resolution radio interferometric measurements, provided that both AGN are in an evolutionary phase when some activity is going on in the radio. We used the technique of Very Long Baseline Interferometry (VLBI) to image SDSS J1425+3231. Observations made with the European VLBI Network (EVN) at 1.7 GHz and 5 GHz frequencies in 2011 revealed compact radio emission at sub-mJy flux density levels from two components with a projected linear separation of \sim2.6 kpc. These two components support the possibility of a dual AGN system. The weaker component remained undetected at 5 GHz, due to its steep radio spectrum. Further study will be necessary to securely rule out a jet--shock interpretation of the less dominant compact radio source. Assuming the dual AGN interpretation, we discuss black hole masses, luminosities, and accretion rates of the two components, using available X-ray, optical, and radio data. While high-resolution radio interferometric imaging is not an efficient technique to search blindly for dual AGN, it is an invaluable tool to confirm the existence of selected candidates.
Nova V1425 Aquilae 1995 - The Early Appearance of Accretion Processes in An Intermediate Polar Candidate  [PDF]
A. Retter,E. M. Leibowitz,O. Kovo-Kariti
Physics , 1997, DOI: 10.1046/j.1365-8711.1998.01058.x
Abstract: Continuous CCD photometry of Nova Aquilae 1995 was performed through the standard B,V,R and I filters during three nights in 1995 and with the I filter during 18 nights in 1996. The power spectrum of the 1996 data reveals three periodicities in the light curve: 0.2558 d, 0.06005 d and 0.079 d, with peak-to-peak amplitudes of about 0.012, 0.014 and 0.007 mag. respectively. The two shorter periods are absent from the power spectrum of the 1995 light curve, while the long one is probably already present in the light curve of that year. We propose that V1425 Aql should be classified as an Intermediate - Polar CV. Accordingly the three periods are interpreted as the orbital period of the underlying binary system, the spin period of the magnetic white dwarf and the beat period between them. Our results suggest that no later than 15 months after the outburst of the nova, accretion processes are taking place in this stellar system. Matter is being transferred from the cool component, most likely through an accretion disc and via accretion columns on to the magnetic poles of the hot component.
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