Search results for "emission"
showing 10 items of 2441 documents
Action-oriented knowledge for sustainable management of organic soils in Finnish agriculture
2023
Agriculture is a contributing force to climate change due to unsustainable changes in land use with the usage of peatlands for food production in Finland. The use of organic soils in food production is a complex and politically driven issue, thus multistakeholder and participatory approaches to policy development, implementation and evaluation are essential. This study is integrating qualitative and quantitative methods in an iterative process to produce action-oriented knowledge for supporting actions to sustainably manage peatlands and reduce the enormous greenhouse gas emissions from agricultural peatlands. This study has engaged inter-disciplinary researchers and transdisciplinary actor…
Dynamical analysis of electron transport in RF cavities and photomultipliers tubes
2021
El objetivo de este trabajo es el estudio de la dinámica de haces y corrientes de electrones en cavidades aceleradoras de radiofrecuencia (RF) y en tubos fotomultiplicadores. Por una parte, los haces de electrones presentan una gran importancia histórica tanto en aplicaciones directas (televisiones, hornos de microondas, tratamiento del cáncer), como en la generación de radiación sincrotrón. La última generación de fuentes de rayos X muy brillantes se basa en los láseres de electrones libres (XFEL). No obstante, para producir los haces de electrones que emitirán dichos rayos X como radiación sincrotrón, se necesitan campos eléctricos de gran intensidad lo que produce que, debido a la emisió…
Inhibition of denitrification and N2O emission by urine-derived benzoic and hippuric acid
2006
Abstract Hippuric acid (HA) in cattle urine acts as a natural inhibitor of soil N2O emissions. As HA concentration varies with diet, we determined critical HA levels. We also tested the hypothesis that the inhibition occurs because the HA breakdown product benzoic acid (BA) inhibits denitrification rates. During a 64-day incubation, we quantified emissions from artificial urine varying in HA, BA and glycine (Gly) concentrations, added to a sandy pasture soil. Increasing HA concentration from 0.4 to 5.6 mmol kg−1 soil significantly decreased the average N2O flux by 54%. At 3.9 mmol kg−1 soil, denitrification levels were 50% reduced for BA as compared to Gly. We conclude that HA inhibits both…
Greenhouse gases from membrane bioreactor treating hydrocarbon and saline wastewater
2015
The effect of wastewater salinity and presence of petroleum hydrocarbon on N2O emission was investigated in a membrane bioreactor, in which the anoxic and aerobic zones were put in series according to a pre-denitrification scheme. The pilot plant, was continuously fed by a mixture of real and synthetic wastewater. It was operated with a first phase of acclimation of the biomass to a given salinity by gradually increasing the salt concentration from 10 gNaCl/L to 20 gNaCl/L, and to a second phase of petroleum hydrocarbon dosing at 2 g/L (as gasoline). The first phase revealed a clear relationship between nitrous oxide emissions and salinity due to the increased NO2-N production caused by the…
A Feasibility Study for the Transition to Electric Mobility in the Island of Favignana
2021
The energy transition and climate neutrality are a short time scenario as climate concerns are rising fast. Small islands are natural microgrids in which the energy transition is subjected to economic and regulatory constraints and highly challenged by technical issues. As a first step, the Mediterranean island of Favignana has been considered in this study, to assess how electric mobility could impact the power system. According to the plans from the local decision makers, the island is moving towards a full public electric mobility in the near term, also due to the participation in the BloRin project. For this reason, a feasibility study about the technical and environmental impact of ele…
Soil aggregates, organic matter turnover and carbon balance in a Mediterranean eroded vineyard
2014
The carbon cycle is being affected by the human impacts (Novara et al., 2011; Yan-Gui et al., 2013), and one of those is the intensification in the soil erosion in agriculture land (Cerdà et al., 2009; García Orenes et al., 2009). Vineyards also are affected by the human activities (Fernández Calviño, 2012). Vineyards in Sicily are cultivated on 110.000 ha, 10% of which on >10% slope. Deficiencies of soil organic matter are typical of the semi arid Mediterranean environment especially where traditional intensive cropping practices are adopted (Novara et al., 2012; 2013). These practices in vineyards could lead soil to intensive erosion processes (Novara et al., 2011). The fate of SOC under …
A Decade of GRB Follow-Up by BOOTES in Spain (2003–2013)
2016
This article covers ten years of GRB follow-ups by the Spanish BOOTES stations: 71 follow-ups providing 23 detections. Follow-ups by BOOTES-1B from 2005 to 2008 were given in a previous article and are here reviewed and updated, and additional detection data points are included as the former article merely stated their existence. The all-sky cameras CASSANDRA have not yet detected any GRB optical afterglows, but limits are reported where available.
Terahertz Spin‐to‐Charge Conversion by Interfacial Skew Scattering in Metallic Bilayers
2021
The efficient conversion of spin to charge transport and vice versa is of major relevance for the detection and generation of spin currents in spin‐based electronics. Interfaces of heterostructures are known to have a marked impact on this process. Here, terahertz (THz) emission spectroscopy is used to study ultrafast spin‐to‐charge‐current conversion (S2C) in about 50 prototypical F|N bilayers consisting of a ferromagnetic layer F (e.g., Ni81Fe19, Co, or Fe) and a nonmagnetic layer N with strong (Pt) or weak (Cu and Al) spin‐orbit coupling. Varying the structure of the F/N interface leads to a drastic change in the amplitude and even inversion of the polarity of the THz charge current. Rem…
Towards controlling PCDD/F production in a multi-fuel fired BFB boiler using two sulfur addition strategies
2014
Abstract PCDD/F abatement strategies – sulfur pellet addition and peat co-combustion – were tested for a BFB boiler facility utilizing SRF-bark-sludge as fuel. In this paper chemical and physical analyses of electrostatic precipitator (ESP) fly ashes were used to explain the differences in the performance of these strategies. These analyses revealed a difference between the coarse and fine fly ashes collected in the ESP. Chemical analysis of the fine fly ashes revealed high concentration of easily volatilized elements while the SEM micrographs showed that fine ash are composed of clusters of spherical particles, thereby leading to a conclusion that fine ashes were originally in a gas phase …
Integrating vehicle specific power methodology and microsimulation in estimating emissions on urban roundabouts
2021
In this study pollutant emissions were estimated from VSP modal emission rates and the distribution of time spent in each VSP mode obtained from the speed profiles both gathered in the field and simulated in AIMSUN at a sample of urban roundabouts. The versatility of the micro-simulation model for a calibration aimed at improving accuracy of emissions estimates was tested in order to ensure that second-by-second trajectories experienced in the field by a test vehicle through the sampled roundabouts properly reflected the simulated speed profiles. The first results which the thesis will refer, confirmed the feasibility of the smart approach that integrates the use of field-observed and simul…