Search results for " Emissions"
showing 10 items of 260 documents
Intercomparison of SO2 camera systems for imaging volcanic gas plumes
2015
Abstract SO 2 camera systems are increasingly being used to image volcanic gas plumes. The ability to derive SO 2 emission rates directly from the acquired imagery at high time resolution allows volcanic process studies that incorporate other high time-resolution datasets. Though the general principles behind the SO 2 camera have remained the same for a number of years, recent advances in CCD technology and an improved understanding of the physics behind the measurements have driven a continuous evolution of the camera systems. Here we present an intercomparison of seven different SO 2 cameras. In the first part of the experiment, the various technical designs are compared and the advantage…
Trace elements mobility in soils from the active hydrothermal area of Nisyros (Greece)
2014
Nisyros Island, Greece, is a stratovolcano known for its intense hydrothermal activity. On June 2013, during a multidisciplinary field campaign, soil samples were collected in the caldera area to determinate the main mineralogical paragenesis and to investigate the distribution of trace elements concentrations and the possible relationship to the contribution of deep originated fluids. Soil samples were analysed with XRD and for the chemical composition of their leachable (deionized water) and near total (microwave digestion) fraction both for major and trace elements. All data were compared to a local background soil. The results allow to divide the samples in 2 groups: Lakki Plain and Ste…
The Effect of Electric Field Configuration on the Thermo-Chemical Conversion of Straw Pellets
2020
Abstract With the aim to control and improve the thermo-chemical conversion of straw pellets, the experimental investigations of the DC electric field effect on the combustion dynamics and heat energy production were made. The electric field effect on the gasification/combustion characteristics was studied using three different positions of the positively charged electrode in flame. First, the electrode was positioned coaxially downstream the flame flow. Next, the electrode was positioned coaxially upstream the flame flow and, finally, the electrode was positioned across the downstream flow. The bias voltage of the electrode varied in the range from 0.6 up to 1.8 kV, while the ion current i…
La evolución energética del sector español de baldosas cerámicas
2014
espanolEl presente texto analiza como ha ido evolucionando el consumo y la eficiencia energetica de la industria espanola de baldosas ceramicas durante el siglo XX, y explora las posibilidades que se le plantean en el siglo XXI. Durante el pasado siglo este sector industrial acometio tres transiciones radicales al pasar de los combustibles tradicionales de biomasa a los hidrocarburos liquidos (fueloleo y gasoleo), y posteriormente a los gaseosos, principalmente gas natural. Aunque la informacion que permite evaluar de manera fiable la eficiencia energetica real en las plantas de fabricacion no es facil de obtener, los datos disponibles indican que se ha llegado a una elevada eficiencia con …
Nitrous oxide emissions in a membrane bioreactor treating saline wastewater contaminated by hydrocarbons
2016
The joint effect of wastewater salinity and hydrocarbons on nitrous oxide emission was investigated. The membrane bioreactor pilot plant was operated with two phases: i. biomass acclimation by increasing salinity from 10 gNaCl L−1 to 20 gNaCl L−1 (Phase I); ii. hydrocarbons dosing at 20 mg L−1 with a constant salt concentration of 20 gNaCl L−1 (Phase II). The Phase I revealed a relationship between nitrous oxide emissions and salinity. During the end of the Phase I, the activity of nitrifiers started to recover, indicating a partial acclimatization. During the Phase II, the hydrocarbon shock induced a temporary inhibition of the biomass with the suppression of nitrous oxide emissions. The r…
Self-enforcing international environmental agreements revisited
2004
In Barrett's (1994) paper on transboundary pollution abatement is shown that if the signatories of an international environmental agreement act in a Stackelberg fashion, then, depending on parameter values, a self-enforcing IEA can have any number of signatories between two and the grand coalition. Barrett obtains this result using numerical simulations and also ignoring the fact that emissions must be non-negative. Recent attempts to use analytical approaches and to explicitly recognize the non-negativity constraints have suggested that the number of signatories of a stable IEA may be very small. The way such papers have dealt with non-negativity constraints is to restrict parameter values…
Management of Greenhouse Gas Emissions for Airport Inventories
2020
Greenhouse gases retain heat in the atmosphere since they absorb most of the Earth's outgoing long wave infrared radiation. The energy trapping alters the radiative balance that, in turn, modifies weather patterns at a global scale, progressively increasing the natural greenhouse effect. Heattrapping ability of some pollutants and primarily the carbon overload in the atmosphere as a result of human activities which have been protracted over a long period of time, has led to climate change and increase in global average temperature. In a long-term perspective, emission abatement from aviation sector has needed wide-ranging strategies. In this view an inventory of greenhouse gases can be a be…
Replacing short-haul flights with land-based transportation modes to reduce greenhouse gas emissions: the case of Finland
2019
Even though air travel often provides the fastest transport option, it also has the highest climate impact. Especially on long-haul trips, an aircraft usually represents the only feasible option. Nevertheless, aircraft are more often used on short-haul routes as well. It is the short-haul flights that produce the highest emissions per passenger. These are also the ones that could be replaced the most easily by land-based transportation modes. This study investigates the greenhouse gas emissions reduction potential of replacing short-haul flights with train, coach and car travel within Finland while also taking into account real travel times from door to door. Our results showed that replaci…
Carbon emissions by Ssouth american companies: driving factors for reporting decisions and emissions reduction
2018
In the last decade, companies have started to disclose information on carbon emissions. To our knowledge, this is the first paper to look into this phenomenon in South America, which is a very important geographical area regarding climate change because of the local nature and developing economies. This paper explores the relationships between some corporate variables and two important decisions: (i) whether to report carbon emissions, and (ii) the impact on the evolution of carbon emissions. Logit and linear panel data models are used to determine the driving factors for decisions (i) and (ii). Our results show that regarding the carbon reporting decision, a company&rsquo
Biogenic Fenton process - A possible mechanism for the mineralization of organic carbon in fresh waters.
2020
To explore the mechanisms that mineralize poorly bioavailable natural organic carbon (OC), we measured the mineralization of OC in two lake waters over long-term experiments (up to 623 days) at different pH and iron (Fe) levels. Both the microbial and photochemical mineralization of OC was higher at pH acidified to 4 than at the ambient pH 5 or an elevated pH 6. During 244 days, microbes mineralized up to 60% of OC in the 10-mu m filtrates of lake water and more than 27% in the 1-mu m filtrates indicating that large-sized microbes/grazers enhance the mineralization of OC. A reactivity continuum model indicated that the acidification stimulated the microbial mineralization of OC especially i…