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The aim of this report is to demonstrate and evaluate the potential of tall wheatgrass (Elytrigia elongata) to avoid GHG emissions and obtain lower economic costs in marginal areas of Spain. Our research built scenarios based on experimental plots (2 and 3 years growth) in 3 locations of Spain with completely different climate conditions (provinces of Girona, Soria and Palencia). In our experiences, we achieved an adequate establishment and biomass production, and assumed a rank of biomass yields until the end of the life cycle that is usually accepted to be about 15 years in many other studies in United States, Argentina and Eastern Europe where tall wheatgrass is extensively cultivated in marginal areas for sheep livestock production. Using our experimental plots and statistical information for economic inputs costs, we built 5 different scenarios per region considering a large range of biomass yields of tall wheatgrass. The analysis included a comparison with annual grasses economic costs calculated for a wide range of biomass yields of a previous study. We estimated GHG emissions savings for tall wheatgrasses and used our previous study (which had GHG emissions savings as well). Savings were calculated replacing natural gas electricity with electricity from biomass combustion in real power plants in Spain. In a wide range of yields, the results suggest that marginal areas might present a better performance with tall wheatgrass compared to annual winter grasses (cereals whole plant cuttings), thus producing biomass yields with higher GHG savings and lower economic costs at the farm level. Proceedings of the 20th European Biomass Conference and Exhibition, 18-22 June 2012, Milan, Italy, pp. 217-229

In this study, air concentrations of BaP in two different seasons (winter 2015 and summer 2016) and BaP levels in ground vegetation from Tarragona County were used as control simulations performed with the WRF-CHIMERE air quality modelling system, in order to reproduce the incidence of that hazardous chemical in air and soils. The CTM was validated for the present climatology, showing a good ability to represent air and soil concentrations of BaP over the target domain (petrochemical, chemical, urban and background sites), particularly in the winter. Then, the variation of the BaP concentrations in air and soils were simulated for the time series 1996-2015 and for the climate change scenario RCP8.5 (2031-2050). While an increase is projected for the levels in air, particularly in chemical and remote sites where the variation can go up to 10%, in terms of soil deposition the findings are the opposite, with an evident decrease in soil BaP concentrations, particularly for background sites. Finally, a potential health effect of BaP for the local population (lung cancer) was assessed. Although according to the projections the EU threshold for BaP atmospheric incidence (1 ng m-3) will not be reached by 2050, there will be an increase in the life-time risk of lung cancer, particularly in the most populated areas within the simulation domain.

Abstract The Mediterranean region is one of the most vulnerable regions to climate change. The majority of climate models forecast a rise in temperatures and less rainfall, which have been observed in recent decades. These changes will affect several vegetation properties, especially phenological dynamics and traits, by increasing drought intensity and recurrence. In this climate change context, the present study aims to assess the evolution of vegetation state and its relation with the climate dynamics in the Mediterranean forest region of northeast Tunisia using Land Surface Phenology (LSP) metrics and the vegetation index (NDVI) analysis from 2000 to 2017. To conduct this work, we used precipitation and temperature data from the two closest weather stations and 16-day NDVI composite images from the MODIS satellite source, with 250-m spatial resolution. Three phenological metrics— start of season (SOS), end of season (EOS), and length of season (LOS) — were obtained and compared for different vegetation types. The LSP variation in response to climatic metrics was also analyzed. The results showed that the LSP in our study area changed significantly during the 2000–2017 period, which includes an average 7.8 days delay in the SOS, an average advance in the EOS by 5 days, and LOS shortened by an average 12.8 days. Autumn (Pr_9) and spring (Pr_3 and P3_4) precipitations, as well as maximum temperature (Tx9+10), represent the best climate parameters to explain the changes in LSP. Both the NDVI and SPEI showed a significant high correlation (p

The electronic energy loss of swift H and He ions in gold is studied, paying special attention to the contribution to the projectile energy loss due to the ionization of the target inner-shells. We calculate the stopping power and the energy-loss straggling as a function of the projectile energy, taking into account the different charge states that the projectile can acquire inside the target and using the dielectric formalism. The electronic response of gold is described by the MELF-GOS model, where the excitation of valence and N-shell electrons is characterized by a linear combination of Mermin-type energy-loss functions, whereas the contribution to the projectile energy loss due to the target K-, L-, and M-shell ionization is included through hydrogenic generalized oscillator strengths. Stopping powers and straggling are, respectively, systematically above and below the data in our linear response formulation when H and He ions are below 0.1 MeV/u. Our calculations show that the total contribution of K-, L-, and M-shells to stopping power and straggling is less than 0.5% and 3.5% below 1 MeV/u, respectively. For stopping powers, the contribution of these inner-shells increases to 9% at 10 MeV/u and continues to rise to 20% at 100 MeV/u. For straggling, it increases to 23% at 10 MeV/u and rises to 35% at 100 MeV/u.

Phosphorus was recovered from the ash obtained after combustion at different temperatures (600 °C, 750 °C, 900 °C) and gasification (obtained at 820 °C using a mixture of air and steam as fluidizing agent) of char from sewage sludge fast pyrolysis carried out at 530 ºC. Depending on the extraction conditions (type of acid, extraction time and acid concentration) phosphorus yields of 90% to 100% are reached. Char ash seems to be a renewable resource of phosphorus. It could be an alternative to rock phosphate for fertilizers production. The combination of these processes contributes to the integral exploitation of sewage sludge. Proceedings of the 21st European Biomass Conference and Exhibition, 3-7 June 2013, Copenhagen, Denmark, pp. 500-505

Abstract The Raman spectra and the Raman parameters have been correlated with changes in the structure of carbon materials, and most of the studies have revealed different development of the Raman spectrum. In the present study micro-Raman spectroscopy was conducted on coal bulk samples and on individual coal macerals (collotelinite, fusinite, and macrinite) from a set of Penn State Coal Bank coals of increasing rank to study the variation of their spectral parameters with rank, and considering coal heterogeneity. The spectral parameters that better correlate with the increasing coal rank, for the coals studied are the full width at half maximum of graphitic band (G: at ∼ 1580 cm− 1), the position of disordered band (D: at ∼ 1350 cm− 1), and the integrated intensity ratio of the D band to G band (ID/IG). With increasing coal rank a narrower G band, a shift of D band to lower wavenumber, and an increase of integrated intensity ratio ID/IG are observed. For each coal, the Raman parameters obtained on fusinites and macrinites are similar and differ from those obtained on coal bulk samples and collotelinites. The variation of the Raman parameters with rank is very well reflected on the analyses of collotelinites.

Abstract We report the electro deposition of In 2 S 3 buffer layers for CuInS 2 solar cells. All materials and deposition conditions were selected taking into account environmental, economic and technological aspects of a potential transfer to large volume industrial production. Different bath compositions and electro deposition parameters were studied. The obtained films exhibited complete substrate coverage, confirmed by SEM and XPS. In/S ratio close to 2/3 was obtained. XPS measurements detected the presence of indium hydroxide, transforming into oxide upon anneal at 200 °C. Maximum photoelectric conversion efficiency of 7.1% was obtained, limited mainly by a low fill factor (51%). Further process optimization is expected to lead to efficiencies comparable to CdS buffers. So far, open-circuit voltages as high as 660 mV were demonstrated.

AbstractThe optical energy‐loss function (ELF) of Au and Al, obtained from experiments, is extended to finite wavenumber k using three different widely used models, namely, with the Mermin type ELFs with generalized oscillator strengths (MELF‐GOS) model, the extended Drude model and the Penn model. The resulting ELFs show important differences but the MELF‐GOS model gives more realistic results when compared with the available experimental ELFs for finite k. These differences affect calculations of important parameters in projectile‐solid interaction. The calculated stopping power and energy‐loss straggling of Au and Al for H projectiles as well as the corresponding inelastic mean free path (IMFP) of electrons in Au and Al clearly show that the results depend on the model used for the ELF description. Comparison with experimental data gives support to the MELF‐GOS model, especially in a material with a complex energy‐loss spectrum such as Au. Copyright © 2008 John Wiley & Sons, Ltd.