1,613 research outputs found
The development of a resource-efficient photovoltaic system
This paper presents the measures taken in the demonstration of the photovoltaic case study developed within the European project ‘Towards zero waste in industrial networks’ (Zerowin), integrating the D4R (Design for recycling, repair, refurbishment and reuse) criteria at both system and industrial network level. The demonstration is divided into three phases. The first phase concerns the development of a D4R photovoltaic concept, the second phase focused on the development of a specific component of photovoltaic systems and the third phase was the demonstration of the D4R design in two complete photovoltaic systems (grid-connected and stand-alone). This paper includes a description of the installed photovoltaic systems, including a brief summary at component level of the lithium ion battery system and the D4R power conditioning system developed for the pilot installations. Additionally, industrial symbioses within the network associated with the photovoltaic systems and the production model for the network are described
The pre-outburst flare of the A 0535+26 August/September 2005 outburst
We study the spectral and temporal behavior of the High Mass X-ray Binary A
0535+26 during a `pre-outburst flare' which took place ~5 d before the peak of
a normal (type I) outburst in August/September 2005. We compare the studied
behavior with that observed during the outburst. We analyse RXTE observations
that monitored A 0535+26 during the outburst. We complete spectral and timing
analyses of the data. We study the evolution of the pulse period, present
energy-dependent pulse profiles both at the initial pre-outburst flare and
close to outburst maximum, and measure how the cyclotron resonance-scattering
feature (hereafter CRSF) evolves. We present three main results: a constant
period P=103.3960(5)s is measured until periastron passage, followed by a
spin-up with a decreasing period derivative of Pdot=(-1.69+/-0.04)x10^(-8)s/s
at MJD 53618, and P remains constant again at the end of the main outburst. The
spin-up provides evidence for the existence of an accretion disk during the
normal outburst. We measure a CRSF energy of Ecyc~50kev during the pre-outburst
flare, and Ecyc~46kev during the main outburst. The pulse shape, which varies
significantly during both pre-outburst flare and main outburst, evolves
strongly with photon energy.Comment: 4 pages, 4 figures, accepted for publication in A&A Letters. To be
published in parallel to Postnov et al. 200
Mitochondrial DNA variability in spanish sheep breeds
Mitochondrial DNA variability was studied in indigenous Iberian sheep and results analysed for each of the four morphological trunks. Three maternal lineages, B, A and C were identified. Mean nucleotide diversity for each of the ovine groups was estimated, showing a lower value for the churro trunk, intermediate values for entrefino and merino trunks, while the iberian group had the greatest mitochondrial diversity. Within the churro trunk all mitochondrial DNA sequences belonged to haplogroup B, also known as European type, and among churro breeds Latxa sheep showed the lowest diversity of all Iberian sheep analysed. A few animals of the entrefino trunk showed a maternal A, or Asiatic, lineage, namely Spanish Manchega and Portuguese Serra da Estrela sheep. In the merino group Merino Branco breed showed differences with the rest of sheep, particularly much greater nucleotide diversity and the presence of animals of maternal lineage A. On the other hand, moderate diversity was evident among the rest of merino populations, as it was the case of Spanish pure Merino for which all animals belonged to maternal lineage B. Finally, the iberian trunk showed the highest mean nucleotide diversity and in this group maternal lineage C was identified. The presence of this mitochondrial DNA type was evident in both breeds corresponding to this trunk: Montesina and Ojalada. This result is of particular relevance since this maternal lineage has been discovered quite recently and mainly in Asiatic ovines.Se estudió la variabilidad en el DNA mitocondrial en distintas razas ovinas ibéricas y los resultados obtenidos se analizaron para cada uno los cuatro troncos etnológicos. Se identificaron los tres linajes maternos conocidos como B, A y C. La diversidad nucleotÃdica promedio estimada para cada uno de los grupos ovinos fue menor para el tronco churro, intermedia para los grupos entrefino y merino, mientras que el tronco ibérico mostró la mayor diversidad mitocondrial. En el tronco churro todas las secuencias de DNA mitocondrial correspondieron al haplogrupo B, también denominado europeo, y entre sus razas la Latxa fue la de menor diversidad de todos las razas Ibéricas analizadas. En el tronco entrefino se identificaron unos pocos animales del linaje materno A, o asiático, en concreto en la raza española Manchega y en la portuguesa Serra da Estrela. En la agrupación merina se encontraron diferencias entre la raza Merino Branco y el resto, mostrando la primera una diversidad nucleotÃdica muy superior, asà como la presencia de algunos animales del linaje A. Por el contrario, en el resto de las poblaciones merinas, entre ellas el Merino puro español, se detectó una variabilidad moderada y sus animales pertenecÃan en todos los casos al linaje materno B. Finalmente, el tronco ibérico presentó el valor promedio más elevado de diversidad nucleotÃdica y en esta agrupación ovina se identificó el linaje materno C. La presencia de este tipo de DNA mitocondrial fue puesta de manifiesto en ambas razas representantes de este tronco, Montesina y Ojalada. Este resultado es de particular relevancia dado que este linaje materno ha sido descubierto no hace mucho tiempo y fundamentalmente en ovinos asiáticos
Quantum-well states in ultrathin Ag(111) films deposited onto H-passivated Si(111)-(1x1) surfaces
Ag(111) films were deposited at room temperature onto H-passivated
Si(111)-(1x1) substrates, and subsequently annealed at 300 C. An abrupt
non-reactive Ag/Si interface is formed, and very uniform non-strained Ag(111)
films of 6-12 monolayers have been grown. Angle resolved photoemission
spectroscopy has been used to study the valence band electronic properties of
these films. Well-defined Ag sp quantum-well states (QWS) have been observed at
discrete energies between 0.5-2eV below the Fermi level, and their dispersions
have been measured along the GammaK, GammaMM'and GammaL symmetry directions.
QWS show a parabolic bidimensional dispersion, with in-plane effective mass of
0.38-0.50mo, along the GammaK and GammaMM' directions, whereas no dispersion
has been found along the GammaL direction, indicating the low-dimensional
electronic character of these states. The binding energy dependence of the QWS
as a function of Ag film thickness has been analyzed in the framework of the
phase accumulation model. According to this model, a reflectivity of 70% has
been estimated for the Ag-sp states at the Ag/H/Si(111)-(1x1) interface.Comment: 6 pages, 6 figures, submitted to Phys. Rev.
Peculiar outburst of A 0535+26 observed with INTEGRAL, RXTE and Suzaku
A normal outburst of the Be/X-ray binary system A0535+26 has taken place in
August 2009. It is the fourth in a series of normal outbursts that have occured
around the periastron passage of the source, but is unusual by starting at an
earlier orbital phase and by presenting a peculiar double-peaked light curve. A
first "flare" (lasting about 9 days from MJD 55043 on) reached a flux of 440
mCrab. The flux then decreased to less than 220 mCrab, and increased again
reaching 440 mCrab around the periastron at MJD 55057. Target of Opportunity
observations have been performed with INTEGRAL, RXTE and Suzaku. First results
of these observations are presented, with special emphasis on the cyclotron
lines present in the X-ray spectrum of the source, as well as in the pulse
period and energy dependent pulse profiles of the source.Comment: 6 pages, Accepted for publication on PoS, Proceedings of "The Extreme
sky: Sampling the Universe above 10 keV", held in Otranto (Italy) in October
200
First DNA barcode reference library for the identification of South American freshwater fish from the lower Paraná river
Valid fish species identification is essential for biodiversity conservation and fisheries management. Here, we provide a sequence reference library based on mitochondrial cytochrome c oxidase subunit I for a valid identification of 79 freshwater fish species from the Lower Paraná River. Neighbour-joining analysis based on K2P genetic distances formed non-overlapping clusters for almost all species with a ≥99% bootstrap support each. Identification was successful for 97.8% of species as the minimum genetic distance to the nearest neighbour exceeded the maximum intraspecific distance in all these cases. A barcoding gap of 2.5% was apparent for the whole data set with the exception of four cases. Withinspecies distances ranged from 0.00% to 7.59%, while interspecific distances varied between 4.06% and 19.98%, without considering Odontesthes species with a minimum genetic distance of 0%. Sequence library validation was performed by applying BOLDs BIN analysis tool, Poisson Tree Processes model and Automatic Barcode Gap Discovery, along with a reliable taxonomic assignment by experts. Exhaustive revision of vouchers was performed when a conflicting assignment was detected after sequence analysis and BIN discordance evaluation. Thus, the sequence library presented here can be confidently used as a benchmark for identification of half of the fish species recorded for the Lower Paraná River.Instituto de LimnologÃa "Dr. Raul A. Ringuelet
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