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Pile burns as a proxy for high severity wildfire impacts on soil microbiomes
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Unveiling dark brown carbon: The hidden light-absorbing aerosols from biomass burning
The global rise in wildfire severity highlights the significant warming impact of brown carbon aerosols. Further, new findings reveal water-insoluble “dark brown carbon” tar balls that absorb far more light than the previously studied water-soluble brown carbon, representing a major unaccounted factor in global Earth System Models.
Revisiting the 3α reaction rates in helium burning stars
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Hot-spot initiated burn waves in heterogeneous-explosive detonation reaction zones: Mixed-mode reaction and the reactive-thermal wave model
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Identifying Waste Burning Plumes Using High-Resolution Satellite Imagery and Machine Learning: A Case Study in the Maldives
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Bioaerosol Emission Characteristics from Laboratory Burns
Combustion processes can aerosolize and transport particles both from nonbiological and biological origin, with the latter termed bioaerosol particle (BAP). Previous work has shown an increase in the level of BAP in smoke plumes. The mechanism of their emission, whether from combustion of biological material or coemission with dust and soil from fire-driven winds, has yet to be examined. Here, we carried out a series of controlled combustion experiments to understand the role of vegetation type and combustion conditions in the direct emission of BAP. The fuels we used included broadleaf, evergreen, and grass. We measured the emitted fluorescent BAP using a wideband integrated bioaerosol system (WIBS), and we measured the viability of filter-collected BAP using flow cytometry. Our measurements showed that the size and absolute concentration of the fluorescent BAP, and the viability of the BAP emitted during combustion, depend on the combustion conditions. In addition, the type of fuel impacted the type of emitted fluorescent BAP fraction relative to the total concentration of the emitted aerosol.
Multi-day photochemical evolution of organic aerosol from biomass burning emissions
Our work highlights how organic compounds in smoke particles will undergo physical and chemical transformations in the presence of sunlight as the smoke is transported over long distances.
Comparison of Reactive Burn Equilibrium Closure Assumptions in CTH.
Abstract not provided.
Extension of the xHVRB Reactive Burn Model for Graded Density Explosives.
Abstract not provided.
Uncertainty Quantification for a TNT Equation of State Including the Kinetic Burn Model
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A thermodynamic condition for ignition and burn-propagation in cryogenic layer inertially confined fusion implosions
A Lawson-like criterion for ignition (where self-heating dominates over all energy losses) in a dynamic implosion is developed, which accounts for asymmetry and for differences in an implosion x-ray confinement quality. It is shown that the thermodynamic ignition condition is equivalent to yield amplification levels of 16–32. Since negative pdV work of expansion after stagnation increases energy losses above that of x-ray and electron-conduction losses, the Lawson-like ignition criterion is necessary but not sufficient for igniting the hot spot to propagate into the DT fuel with sufficient vigor to generate high gain. Additionally, a higher dimensional generalization of the Lawson-like criterion, which includes the cooling of the implosion upon disassembly, does provide the needed criteria, and it shows that significantly higher temperature is needed for very high levels of yield amplification compared to what traditional ignition metrics imply.
Reaching a burning plasma and ignition using smaller capsules/ Hohlraums , higher radiation temperatures, and thicker ablator/ice on the national ignition facility
In indirect-drive implosions, the final core hot spot energy and pressure and, hence, neutron yield attainable in 1D increase with increasing laser peak power and, hence, radiation drive temperature at the fixed capsule and Hohlraum size. Here we present simple analytic scalings validated by 1D simulations that quantify the improvement in performance and use this to explain existing data and simulation trends. Extrapolating to the 500 TW National Ignition Facility peak power limit in a low gas-fill 5.4 mm diameter Hohlraum based on existing high adiabat implosion data at 400 TW, 1.3 MJ and 1 × 10 16 yield, we find that a 2–3 × 10 17 yield (0.5–0.7 MJ) is plausible using only 1.8 MJ of laser energy. Based on existing data varying deuterium–tritium (DT) fuel thickness and dopant areal density, further improvements should be possible by increasing DT fuel areal density, and hence confinement time and yield amplification.