Results 251 to 260 of about 1,726,040 (290)

Dry and Wet Deposition

1990
Deposition phenomena are the way in which the atmosphere cleans itself. The process is efficient as only a few gases (most notably CO 2) show signs of global increase in spite of the large emission of pollutants from both natural and anthropogenic sources.
openaire   +1 more source

Deposition by Rain and Snow - Dry Deposition on Snow

1989
A comparative investigation of winter rain and snow is based on a sampling period from November 1986 until April 1987 at two stations at different altitudes. The average element concentrations were enhanced for snow samples. The element specific enrichment factors range from 1.1 to 4.5.
S. Grosch, H.-W. Georgii
openaire   +1 more source

Dry deposition of 214Pb to conifers

Atmospheric Environment, 1997
Abstract The dry deposition of 214Pb was investigated by measuring airborne activity and activity accumulated on Douglas fir branches. This radioisotope is a natural tracer for submicron aerosol. The correlation of the deposition velocity with turbulence intensity is poor.
G.P. Wyers, A.C. Veltkamp
openaire   +1 more source

Dry deposition of nitrates on the Parthenon

Science of The Total Environment, 1991
Abstract The surface density of nitrates on the columns of the Parthenon, Greece, was determined at the end of the Athenian dry season. It is highly probable that this is a measure of the corrosion of marble by photochemically formed nitric acid and nitrates in the atmosphere of Athens.
Photini Delopoulou, Denis Sikiotis
openaire   +1 more source

Measurement of Dry Deposition to Vegetative Surfaces

Water, Air, and Soil Pollution, 1986
The importance of dry deposition was assessed to oak and pine trees, in a hardwood and coniferous canopy, respectively. In both canopies, ambient particle and gas concentrations on the interior were decreased relative to perimeter concentrations due to dry deposition scavenging by the canopy.
openaire   +1 more source

Dry Deposition of Trace Elements

1989
This chapter reviews current knowledge of dry deposition of trace elements from the atmosphere. The process of dry deposition is presented through descriptions of physical processes and mathematical relations. Semi-empirical models are discussed and compared.
Cliff I. Davidson, Yee-Lin Wu
openaire   +1 more source

Dry Deposition of NoX

1982
ABSTRACT The available information regarding deposition of NOX is very limited. Estimates, however, indicate that dry deposition of NO2 and of nitrates may give a significant contribution to the removal of NOX from the lower troposphere, on a global scale as well as in industrialised zonis.
openaire   +1 more source

Dry Deposition to Snowpacks

1991
Dry deposition refers to the transfer of gases and particles to ground-based surfaces, where they are removed. The two main reasons for studying dry deposition are: (1) The determination of the quantity of a species entering the environment. Interest usually centers on species such as SO4 −2 or toxic trace metals that may harm components of aquatic or ...
openaire   +1 more source

Discussion of “Dry Deposition to Snowpacks”

1991
Dry deposition is part of the overall atmosphere-surface exchange process and is the result of a net balance between the atmosphere-to-surface fluxes and the surface-to-atmospheric fluxes. In the overall process, gasses can be reversibly absorbed or adsorbed deposited and particulate matter can be resuspended.
openaire   +1 more source

Automated dry deposition sampler

, 1995
A dry deposition sampling apparatus having at least one thin dry deposition plate with sample collection film is maintained on a support structure which is rotatable about a vertical axis and has a vane to maintain the sharp leading edge of the dry ...
HOLSEN THOMAS M, NOLL KENNETH E
openaire   +2 more sources