Fallout mass-size distributions presently used at USNRDL are compared vith new distributions suggested by recent investigations. Available data is unable to define the distribution parameters well enough to distinguish between lognormal and power-law distribution models.,

introduction artificial and natural radionuclides are found in diverse environmental compartments, such as water, soil, rocks, vegetables, animals, and human body tissues. as such, humans and environments are at constant exposure of these radiation types. in this research investigated specific activities of radionuclide and dose assessment of some species of mushrooms. materials and methods in ...

statement of problem: condylar hyperplasia of the mandible is a self limiting abnormality which can cause facial asymmetry, temporomandibular joint (tmj) dysfunction and esthetic problems. treatment planning is based on the results of isotope scanning, clinical findings and patient age. single photon emission tomography (spect) is considered to be a sensitive method in the calculation of condyl...

The components and quantities of atmospheric dusts fallout has been reported to be the pollution indicator of large urban areas. The multiplicity and complexity of sources of atmospheric dusts in urban regions (e.g. industrial complexes composed of a variety of industrial processes, automobiles, construction activities etc.) has put forward the need of source apportionment of these sources indi...

Different approaches of source apportionment of dust fractions have been reported world-over. Predicting source categories within receptor chemical profiles using regression and factor analysis using PCA has been reported to evaluate possible source/routes of air pollution mass. The present study is focused on the application of all three approaches to investigate higher degrees of significance...

The Great Lakes basin is of radiologic interest due to the large population within its boundaries that may be exposed to various sources of ionizing radiation. Specific radionuclides of interest in the basin arising from natural and artificial sources include 3H, 14C, 90Sr, 129I, 131I, 137Cs, 222Rn, 226Ra, 235U, 238U, 239Pu, and 241Am. The greatest contribution to total radiation exposure is th...

We examine the settling of monodisperse heavy particles released into a fluid when the resulting motion is sufficiently vigorous that the particle cloud initially assumes the form of a turbulent thermal. A laboratory study is complemented by numerical simulations of particle cloud dynamics in both homogeneous and stratified ambients. In the homogeneous ambient, the cloud generated by a total bu...