Measurement and Modeling of Particle Radiation in Coal Flames

This work aims at developing a methodology that can provide information of in-flame particle radiation in industrial-scale flames. The method is based on a combination of experimental and modeling work. The experiments have been performed in the high-temperature zone of a 77 kWth swirling lignite flame. Spectral radiation, total radiative intensity, gas temperature, and gas composition were measured, and the radiative intensity in the furnace was modeled with an axisymmetric cylindrical radiation model using Mie theory for the particle properties and a statistical narrow-band model for the gas properties. The in-flame particle radiation was measured with a Fourier transform infrared (FTIR) spectrometer connected to a water-cooled probe via fiber optics. In the cross-section of the flame investigated, the particles were found to be the dominating source of radiation. Apart from giving information about particle radiation and temperature, the methodology can also provide estimates of the amount of soot radiation and the maximum contribution from soot radiation compared to the total particle radiation. In the center position in the flame, the maximum contribution from soot radiation was estimated to be less than 40% of the particle radiation. As a validation of the methodology, the modeled total radiative intensity was compared to the total intensity measured with a narrow angle radiometer and the agreement in the results was good, supporting the validity of the used approach

Electrical ignition energies and thermal autoignition temperatures for evaluating explosion hazards of dusts /

Includes bibliographical references (p. 36-39).Mode of access: Internet

Spectroscopic evidence of hippocampal abnormalities in neocortical epilepsy

Lesional neocortical epilepsy (NE) can be associated with hippocampal sclerosis or hippocampal spectroscopic abnormalities without atrophy (dual pathology). In this study, magnetic resonance spectroscopic imaging (MRSI) was used to determine the frequency of hippocampal damage/dysfunction in NE with and without structural lesion. Sixteen patients with NE [seven temporal NE (NE-T), nine extratemporal (NEET)] and 16 controls were studied with a 2D MRSI sequence (Repetition time/echo time (TR/TE) = 1800/135 ms) covering both hippocampi. Seven NE patients had MR visible lesions (NE-Les), nine had normal MRI (NE-no). In each hippocampus, 12 voxels were uniformly selected. In controls, mean (SD) NAA/(Cr + Cho) values for each voxel were calculated and voxels with NAA/(Cr + Cho) <= (mean in controls - 2SD in controls) were defined as 'pathological' in patients. Eight of 16 NE patients had at least two 'pathological' voxel (mean 2.5, range 2-5) in one hippocampus. Four were NE-Les and four NE-no. Three (43%) NE-T patients, had evidence for hippocampal damage/dysfunction and five (56%) had NE-ET. The ipsilateral hippocampus was affected in six of eight NE patients. Evidence for unilateral hippocampal damage/dysfunction was demonstrated in 50% of the NE patients. The type of NE, i.e. NE-Les or NE-no, NE-T or NE-ET, had no influence on the occurrence of hippocampal damage/dysfunction

Ignitability testing for core drilling system. Final report

As part of a study of the hazards of the inspection of nuclear waste material stored at the Hanford, WA site, the Department of Energy (DOE) and Westinghouse Hanford Company (WHC) have developed a core drilling system to sample the material in large waste storage tanks. In support of this work, the US Bureau of Mines has studied the probability of ignition while core drilling into simulated salt cake that was permeated with a flammable gas mixture. No ignitions were observed while core drilling into the saltcake with or without a purge gas and no ignitions were observed while drilling into a steel plate

Improved 6.8-L furnace for measuring the autoignition temperatures of dust clouds /

Includes bibliographical references (p. 17).Mode of access: Internet