A survey of the northern hemisphere for astrophysical point sources with continuous emission of high-energy cosmic rays is presented. Around 4:7 ; 10 extensive air showers with primary energies above 300 TeV measured by the KASCADE detector field are selected for this analysis. Besides the sky survey, a search for signal excess in the regions of the Galactic plane and of selected point-source c...

this study, combustion in a 5kW porous burner is simulated. The two dimensional Navier-Stokes, the energy and the chemical species transport equations are solved and a multistep kinetics mechanism (5 reactions and 7 species) is employed. Finite volume method is used for simulation. Thermal nonequilibrium is accounted for gas and solid temperature and radiation heat transfer is considered for so...

[1] Observation-based surface ocean DC distributions and regional inventories for excess, bomb-produced radiocarbon are compared with results of two ocean models of intermediate complexity. By applying current descriptions of the air-sea gas exchange the models produce similar column inventories for excess C among all basins. This result is robust across a wide range of transport parameter sett...

Purpose of this study is to numerically investigate combustion within a porous channel, which has three layers with different pore densities. Non-premixed inside the channel modelled thermal non-equilibrium energy equations. Flow and chemistry are decoupled tabulated using flamelets, thereby reducing computational cost. GRI 3.0 mechanism used account for methane/air combustion. Simulations perf...

Historical records show that the A.D. 1783-1784 Laki eruption in Iceland caused severe environmental stress and posed a health hazard far beyond the borders of Iceland. Given the reasonable likelihood of such an event recurring, it is important to assess the scale on which a future eruption could impact society. We quantify the potential health effects caused by an increase in air pollution dur...

This paper presents an analytical system for analysis of all single substituted isotopologues (COO, COO, COO) in nanomolar quantities of CO2 extracted from stratospheric air samples. CO2 is separated from bulk air by gas chromatography and CO2 isotope ratio measurements (ion masses 45 / 44 and 46 / 44) are performed using isotope ratio mass spectrometry (IRMS). The O excess (1O) is derived from...

In order to demonstrate that the frequency blue-shift corresponds mainly to the existence of thin air layers, simulations including these layers have been carried out. To this end, the thickness of the stacked hole array was measured with a caliper. The result obtained was 140 μm excess of thickness. This excess of thickness can be judiciously attributed to thin air gaps between the four joints...