By Macatee S.R.

Naomi Pasachoff's Marie Curie and the science of radioactivity PDF

Examines the lifetime of the Polish-born scientist who, together with her husband Pierre, was once provided a 1903 Nobel Prize for locating radium.

At the present time, radar in a single shape or one other is probably going to show up in every single place: on the street, on the waterfront, in an underground motor-road. through a ways the widest use of radar is made by way of the army and scientists. In all of those fields millions upon hundreds of thousands of radar units are at paintings. a few of them are sufficiently small to be outfitted into spectacles, others weigh enormous quantities of lots.

Extra info for Considerations in grounding and shielding computer-controlled audio devices

Example text

Jones (1981b) suggests that changes in wind direction may only exert a small effect on the annual average concentration at long distances in a given sector for two reasons. Firstly, directional changes resulting in the transfer of material between sectors will tend to balance out. Secondly, concentrations at great distances are largely determined by neutral conditions in which the trajectories are likely to be approximately straight. Jones (1981b) suggests therefore that for releases in the UK, long range dispersion can be approximated by assuming that they occur in neutral stability with a boundary layer depth of 800 m, but allowing for a range of wind speeds.

Dry deposition is a complex process by which particulates and gases are removed from the air by impaction with the ground and vegetation. g. g. stability and friction velocity) and can be estimated using the concept of a deposition velocity (Vg ). Deposition velocity is deﬁned as the ratio of the amount of material deposited on the ground per unit area per unit time, to the air concentration per unit volume just above the ground (usually at 1 m height). Deposition velocity is often expressed in units of metres per second (m s−1 ).

The model aims to calculate the probability that material will be carried to the point of interest by considering the probability distributions of horizontal and vertical wind speed. 7. 1. 2 are plume models of various types and are primarily for use with distances over which it may be assumed that the mean wind direction and other meteorological parameters do not change. This is typically a few tens of kilometres and up to about 100 km. When modelling long range dispersion the assumption of constant meteorological conditions becomes less valid due to the increased likelihood of changes in meteorological conditions.