Search results for "METHANE"

High diversity of methanotrophic bacteria in a geothermal site: Pantelleria island

2013

Model, software and database for line-mixing effects in the ν3 and ν4 bands of CH4 and tests using laboratory and planetary measurements-I: N2(and ai…

2006

International audience; Absorption spectra of the infrared ν3 and ν4 bands of CH4 perturbed by N2 over large ranges of pressure and temperature have been measured in the laboratory. A theoretical approach accounting for line mixing is proposed to (successfully) model these experiments. It is similar to that of Pieroni et al. [J Chem Phys 1999;110:7717–32] and is based on state-to-state rotational cross-sections calculated with a semi-classical approach and a few empirical parameters. The latter, which enable switching from the state space to the line space, are deduced from a fit of a single room temperature spectrum of the ν3 band at 50 atm. The comparisons between numerous measured and ca…

Biotic oxidation of methane in landfills in boreal climatic conditions

2010

 This study focused on the biotic oxidation of methane in landfill covers as a technology for reducing greenhouse gas emissions from landfills, particularly those located in the boreal climatic zone. First, methane oxidation was studied in laboratory batch assays in a landfill cover soil consisting of a composted mixture of sewage sludge and chemical sludge which had been installed on the landfill surface 4-5 years earlier. Second, methane oxidation was studied using mechanically-biologically treated municipal solid waste (MBT residual) as a material for methane-oxidizing landfill covers both in continuously methane-sparged laboratory columns and in an outdoor pilot lysimeter. Finally, meth…

Soils as natural filters for GHG: an imbalance between the expected CH4 fluxes and the direct measurements

2018

The final composition of the atmosphere results from several processes and exchanges between all the Earth’s spheres. Some of these are widely known and others, such as the methane degassing from hydrothermal areas, are still understudied. Methane plays a key role in climate change being an efficient greenhouse gas. Although it would be crucial, the total CH4 output from geogenic sources is still not well defined; limitations in CH4 output estimations are due to many factors concerning a scarce dataset availability, difficulty in direct measurements, and interaction with methane-consuming microbiota in the soil. Often, the CH4 flux estimation was obtained indirectly, e.g. cross-correlating …

Investigation of the methanotrophic activity in the soils of a geothermal site of Pantelleria Island (Italy)

2013

Profiling microbial communities in hyperalkaline waters of the Kizildag ophiolite complex (Turkey).

2016

It has recently been hypothesized that life on Earth could have been originated in hyperalkaline waters related to serpentinization of ophiolitic rocks, despite their extreme conditions (high pH and very low levels of nutrients). Five hyperalkaline springs of the Kizildag ophiolite complex (Turkey) were characterized. The dominant gases are either H2, CH4 or N2 . Bacterial diversity, analysed by RISA (Ribosomal Intergenic Spacer Analysis) revealed different profles for each spring. Sequencing of excised DNA bands allowed to identify the presence of Bacillus, Ralstonia, Pseudoalteromonas., Ureibacillus, Alicycliphilus, Anaerococcus. 16S ribosomal DNA sequencing by Illumina is in progress. Th…

CCDC 863441: Experimental Crystal Structure Determination

2012

Related Article: P.Svec, R.Olejnik, Z.Padelkova, A.Ruzicka, L.Plasseraud|2012|J.Organomet.Chem.|708|82|doi:10.1016/j.jorganchem.2012.02.022

Sensitivity analysis in investment project of biogas plant

2017

The article shows the practical value of biogas as the second generation biofuel. All the projects dealing with biogas are subjected to external risks, such as the change of market condition, customer needs, governmental regulation, etc. In conditions of uncertainty it is necessary for administration to concentrate on decisionmaking. Fluctuations of sales volume, energy resources and raw material prices, etc. should be taken into account. Sensitivity analysis can predict the result of negative external pheno mena. We developed the economic-mathematical model for the analysis of biogas complexes sensitivity. The profitability index as a criterion for the effectiveness of investment projects …

Anaerobic co-digestion of microalgae and primary sludge in an anaerobic membrane bioreactor for resource recovery (biogas and bionutrients) from urba…

2020

El consumo continuo de energía primaria ha motivado a la comunidad científica a buscar tecnologías que requieran un menor consumo de recursos y fuentes alternativas de energía renovable, que puedan sustituir a los combustibles fósiles. El cultivo de microalgas en combinación con tecnologías anaerobias surgió como una tecnología prometedora y sostenible en el ámbito del tratamiento de aguas residuales. La valorización de la biomasa de microalgas mediante la digestión anaerobia (AD) permite la producción de energía a partir de corrientes de residuos. Dado que la AD de microalgas presenta algunos inconvenientes que obstaculizan la eficiencia del proceso, se ha estudiado la co-digestión anaerob…

A stable isotope study of the hydrological and carbon cycle in meromictic lake, Lovojärvi

2012

Lake Lovojärvi, at its deepest point of 17.5 m, is permanently stratified forming two water layers. The mixolimnion (the upper layer, from 0 to 10 m depth) is affected by seasonal changes while the monimolimnion (bottom layer, from 10 to 17.5 m depth) does not mix and is not affected by seasonal changes. As a result, the lake stores large quantities of dissolved inorganic carbon and methane. I used a multiple stable isotope approach to gain insight into the carbon cycle and water balance of Lovojärvi. The δ18O and δ2H profiles reveal that at the 7 m depth in the mixolimnion, there is a sub-surface stream whose isotopic characteristics are similar to surface streams from a nearby mire, sugge…