180 research outputs found
Rapid, 5 min, low temperature aqueous platinization for plastic substrates for dye-sensitized solar cells
This paper reports a rapid (5 min), low temperature (120 �C) method to platinize the counter electrodes
of dye-sensitized solar cell (DSC) devices. This new method uses aqueous solutions and is based on chemical
bath deposition of an activating Pd layer followed by Pt only using H2 gas as the reductant. This
method has been tested on flexible, plastic substrates (indium tin oxide-coated polyethylene terephthalate
or polyethylene naphthalate, ITO-PET or ITO-PEN, respectively). We report device efficiencies up to
7.2% on ITO-PET which is comparable to devices made using high temperature (400 �C) processing on
rigid, fluoride-doped tin oxide (FTO) glass counter electrodes. The method is scalable and suitable for continuous
roll-to-roll production
The presence of the brown bear (Ursus arctos, L.) in the north eastern Alps (Friuli Venezia Giulia region) in relation to the Alpine metapopulation
The North Eastern Alps (Friuli Venezia Giulia Region) represent a peripheral area of presence of the Dinaric population (for the North Dinaric population, Slovenia, 400-450 individuals estimated) of the Brown Bear; in this area in the last years some individuals has started to come from Trentino population (40-45 individuals estimated) and to use this areas. In previous 114 researches this area has been considered one of the most suitable areas, in the alps, for supporting the alpine brown bear population and for enhancing the creation of the alpine metapopulation. From 2004 to the 2013 in mountains areas of the Friuli Venezia Giulia has been studied (2500 km2) the presence of the Brown Bear with different techniques: the genetic sampling (by opportunistic and systematic methods), photo interpretation and behavioral analysis and radiotelemetry. The genetic samplings have been obtained by the hair traps (50 permanent hair traps plus 80 temporary and moving hair traps) and by opportunistic techniques. By the genetic analysis it has detected the presence, from 2004, of 21 different genotypes (4 from Trentino and 17 from the Dinaric population, 3 of them studied by telemetry), all of them were males. The number of genotypes detected in different year has showed a cyclic pattern, with a increment in the last year, due to dispersing individuals from Dinaric source population; in different years, from 3 to 8 (2013), different genotypes have been detected, with a evident turnover. The median time of presence (years of sampling), for each genotypes, was 2 years, and only 6 genotypes have been sampled for 3 or more years (1 from Trentino); 10 genotypes have been sampled in only one year. Despite to the increment of the Trentino population and the high density of the Dinaric populations, in the north eastern alps the process of immigration and colonization appears to be slow and intermittent and seems correlated more to the demographic aspects (i.e localization and philopatry of the females, now present only in the Alpine and Dinaric areas of Slovenia and on the right side of Adige river, in Trentino), management of the Dinaric population, dispersal behavior and presence of not permeable infrastructure (high way Ljubljana-Trieste) rather than the ecological values of the areas
Presence and distribution of the brown bear (Ursus arctos) in Friuli Venezia Giulia, from 2004 to 2011, through the non-invasive genetic monitoring ad conservation implications
After having disappeared at the beginning of 1900, the brown bear has started in a late 1960s a slow process of recolonization of the north-eastern Alps, through an expansion of Dinaric population. At the end of the 1990s the University of Udine began the occasional monitoring of the species and from 2004 non-invasive genetic monitoring became systematic. In the last 8 years 217 hair traps have been activated in the region to monitore: Natisone Valleys, the Julian and Carnic Alps and Prealps. Twenty-six hair traps were monitored in all years, whereas 40 were observed only in 2004, 2007 and 2011. The 26 hair traps constantly monitored from 2004 to 2011 showed 17% of average success of hair’s collecting (brown bear samples collected/day control: BBSD). The 40 hair traps, monitored in the window period, showed 12% of BBSD. The BBSD value varied in relation to both season (highest in spring) and year, with a dramatic decline from 2008, and interaction between year and area. From 2004, 13 genotypes, through systematic hair traps monitoring, were identified, while only 2 genotypes were sampled opportunistically. It was observed a high turnover of the genotypes: only 7 genotypes were sampled for more than 2 years (47% of total), 4 genotypes (27% of the total) were sampled for 3 years or more. The annual attendance of bear have been constant from 2004 to 2007, with 5-6 genotypes present every year. In the period between 2008 and 2010 there was a drastic decrease in the successful collection at the hair traps, with and average of 1-2 animals genotyped per year. However, opportunistic samples have increased in the recent times, probably due to the arrivals of 3 genotypes from Trentino (KJ2G2 in 2009 and DG2 and MJ4 in 2011). The year 2011 showed a further increase in the presence of bears with 5 animals genotyped in Friuli Venezia Giulia. Three of these animals belonged to the Slovenian population, while the other 2 genotypes were from the Trentino population. The results seem to confirm the exchange of some individuals between the Dinaric and central alpine population. As an example, the dinaric bear M5 was genotyped in Friuli Venezia Giulia in 2008 and then sampled in 2009 and captured in 2010 in Trentino and finally slot in Slovenia in 2011. The distribution in the alpine and prealpine areas has changed year by year: from the 2004 to 2007 the Natisone Valley and the Julian prealpine areas along the border with Slovenia were the areas more used, whilst from 2009 there was an apparent higher presence of bears in the Carnian Prealps and Alps, and in the Julian Alps. This shift could be due to human disturbance (i.e hunting management), control of the species carried out in neighbouring Slovenia, with a decreasing of immigrant from dinaric populations, and new immigration of bears from the central Alps. The present work has highlighted the necessity for a trans-regional and cross-border management of the species, especially in consideration to the population control applied in Slovenia, which seem to limit the Dinaric population expansion in the Alps, and furthermore the philopatry behaviour of bear females, which implies the absence of females in Friuli Venezia Giulia and induces a movement bach to Slovenia (at least 3 bears genotyped in Italy were shot in Slovenia). All these elements seem to exert important limitations to the consolidation and stabilization of the population of brown bears in north-eastern Alps. From the methodological point of view the protocol of systematic non-invasive genetic monitoring, shared at the trans-regional and trans-boundary level, is fundamental to monitore the dynamics and distribution of bear; the protocol should follow a systematic experimental design and should be integrated with a efficient opportunistic data collection
L\u2019uso dei dati di posizionamento e i ritmi di attivit\ue0 per la gestione conservativa dell\u2019Orso nell\u2019area compresa tra il Friuli Orientale e la Slovenia
5openopenCABONI A; VEZZARO S; SALERNO B; FATTORI U; FILACORDA SCaboni, A; Vezzaro, S; Salerno, B; Fattori, U; Filacorda, Stefan
Critical temperature of non-interacting Bose gases on disordered lattices
For a non-interacting Bose gas on a lattice we compute the shift of the
critical temperature for condensation when random-bond and onsite disorder are
present. We evidence that the shift depends on the space dimensionality D and
the filling fraction f. For D -> infinity (infinite-range model), using results
from the theory of random matrices, we show that the shift of the critical
temperature is negative, depends on f, and vanishes only for large f. The
connections with analogous results obtained for the spherical model are
discussed. For D=3 we find that, for large f, the critical temperature Tc is
enhanced by disorder and that the relative shift does not sensibly depend on f;
at variance, for small f, Tc decreases in agreement with the results obtained
for a Bose gas in the continuum. We also provide numerical estimates for the
shift of the critical temperature due to disorder induced on a non-interacting
Bose gas by a bichromatic incommensurate potential.Comment: 18 pages, 8 figures; Fig. 8 improved adding results for another value
of q (q=830/1076
First Dark Matter Results from the XENON100 Experiment
The XENON100 experiment, in operation at the Laboratori Nazionali del Gran
Sasso in Italy, is designed to search for dark matter WIMPs scattering off 62
kg of liquid xenon in an ultra-low background dual-phase time projection
chamber. In this letter, we present first dark matter results from the analysis
of 11.17 live days of non-blind data, acquired in October and November 2009. In
the selected fiducial target of 40 kg, and within the pre-defined signal
region, we observe no events and hence exclude spin-independent WIMP-nucleon
elastic scattering cross-sections above 3.4 x 10^-44 cm^2 for 55 GeV/c^2 WIMPs
at 90% confidence level. Below 20 GeV/c^2, this result constrains the
interpretation of the CoGeNT and DAMA signals as being due to spin-independent,
elastic, light mass WIMP interactions.Comment: 5 pages, 5 figures. Matches published versio
Material screening and selection for XENON100
Results of the extensive radioactivity screening campaign to identify
materials for the construction of XENON100 are reported. This Dark Matter
search experiment is operated underground at Laboratori Nazionali del Gran
Sasso (LNGS), Italy. Several ultra sensitive High Purity Germanium detectors
(HPGe) have been used for gamma ray spectrometry. Mass spectrometry has been
applied for a few low mass plastic samples. Detailed tables with the
radioactive contaminations of all screened samples are presented, together with
the implications for XENON100.Comment: 8 pages, 1 figur
Dark Matter Results from 100 Live Days of XENON100 Data
We present results from the direct search for dark matter with the XENON100
detector, installed underground at the Laboratori Nazionali del Gran Sasso of
INFN, Italy. XENON100 is a two-phase time projection chamber with a 62 kg
liquid xenon target. Interaction vertex reconstruction in three dimensions with
millimeter precision allows to select only the innermost 48 kg as ultra-low
background fiducial target. In 100.9 live days of data, acquired between
January and June 2010, no evidence for dark matter is found. Three candidate
events were observed in a pre-defined signal region with an expected background
of 1.8 +/- 0.6 events. This leads to the most stringent limit on dark matter
interactions today, excluding spin-independent elastic WIMP-nucleon scattering
cross-sections above 7.0x10^-45 cm^2 for a WIMP mass of 50 GeV/c^2 at 90%
confidence level.Comment: 5 pages, 5 figures; matches accepted versio
Implications on Inelastic Dark Matter from 100 Live Days of XENON100 Data
The XENON100 experiment has recently completed a dark matter run with 100.9
live-days of data, taken from January to June 2010. Events in a 48kg fiducial
volume in the energy range between 8.4 and 44.6 keVnr have been analyzed. A
total of three events have been found in the predefined signal region,
compatible with the background prediction of (1.8 \pm 0.6) events. Based on
this analysis we present limits on the WIMP-nucleon cross section for inelastic
dark matter. With the present data we are able to rule out the explanation for
the observed DAMA/LIBRA modulation as being due to inelastic dark matter
scattering off iodine at a 90% confidence level.Comment: 3 pages, 3 figure
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