Methane is a potent greenhouse gas, to which enteric fermentation from ruminants contributes significantly. Reliable and accurate predictions of methane (CH4) production from dairy cows would be of interest to develop mitigation strategies and for national inventories. Thus, the overall aim of this thesis was to predict CH4 production in dairy cows by modelling approaches. Predicted in vivo CH4...

the volumetric changes in the coal matrix (coal shrinkage), permeability under various gas environment conditions as well as perographical properties were studied in the laboratory. the shrinkage and permeability of coal were examined with respect to changing gas type and confining pressures. the shrinkage tests were carried out in high-pressure bombs while the permeability study was conducted ...

[1] Spatial variability of methane (CH4) on Mars suggests the presence of localized subsurface sources. Here, we show that olivine hydration in the Martian regolith and crust may be a major CH4 source, which contributed significantly to the warming of early Mars. Methane production is kinetically and thermodynamically favored during low-T aqueous alteration of olivine-rich rocks. Sustained rele...

The Aliso Canyon gas storage facility near Porter Ranch, California, produced a large accidental CH4 release from October 2015 to February 2016. The Hyperion imaging spectrometer on board the EO-1 satellite successfully detected this event, achieving the first orbital attribution of CH4 to a single anthropogenic superemitter. Hyperion measured shortwave infrared signatures of CH4 near 2.3 μm at...

M anagement of livestock wastes can affect greenhouse gas emissions through attenuating both methane and nitrous oxide emissions, as well as by displacing carbon dioxide emissions from fossil fuel use that can be avoided through biogas production and use. Methane is naturally produced from the anaerobic decomposition of livestock manure and is a potent greenhouse gas with 21 times the greenhous...

Effects of H2O on the activity and deactivation of Pd catalysts used for the oxidation of unburned CH4 present in the exhaust gas of natural-gas vehicles (NGVs) are reviewed. CH4 oxidation in a catalytic converter is limited by low exhaust gas temperatures (500–550 °C) and low concentrations of CH4 (400–1500 ppmv) that must be reacted in the presence of large quantities of H2O (10–15%) and CO2 ...

The gas push-pull test (GPPT) is a single-well gas-tracer method to quantify in situ rates of CH4 oxidation in soils. To improve the design and interpretation of GPPT field experiments, gas component transport during GPPTs was examined in abiotic porous media over a range of water saturations (0.0 < or = Sw < or = 0.61). A series of GPPTs using He, Ne, and Ar as tracers for CH4 were performed a...

Atmospheric methane (CH4) is the second strongest greenhouse gas and it is emitted to the atmosphere naturally by different sources. It is crucial to define the dimension of these natural emissions in order to forecast changes in atmospheric CH4 mixing ratio in future scenarios. However, CH4 emissions by seagrass ecosystems in shallow marine coastal systems have been neglected although their gl...

To get a mole of a gas, it is necessary to calculate the intermolecular interaction. Theseintermolecular interactions can be depicted by drawing the potential energy of a pair molecule inrelation to the distance. The intermolecular potential energy surface in the mixtures of CH4-H2COgases from ab initio calculations has been explored. In ab initio calculations the basis setsuperposition error (...

zno nanostructures of different methods and sizes were grown in a controlled manner using a simple hydrothermal and sonochemical technique. controlling the content of concentration and temperature of the reaction mixture, spherical nanoparticles zno structures could be synthesized at temperatures 100-150 °c with excellent reproducibility in solvothermal and at different power and time in sonoch...