Analysis of time series of particle size distributions in nano exposure assessment

Ångström coefficient as an indicator of the atmospheric aerosol type for a well-mixed atmospheric boundary layer : Part 1: Model development

The physical and optical properties of an atmospheric aerosol mixture depend on a number of factors. The relative humidity influences the size of hydroscopic particles and the effective radius of an aerosol mixture. In consequence, values of the aerosol extinction, the aerosol optical thickness and the Ångström coefficient are modified. A...

Influence of aerosols on off-axis laser detection capabilities

The radiation coming from a laser which operates in the coastal zone can be detected not only when a detector is placed in front of the laser beam but also when it is located outside the main beam direction. The reason is that in a real detection scheme the power collected by a detector not only comes from direct radiation but also from other...

Measurement of optical refraction-, transmission- and turbulence effects in the False Bay, South Africa; June 2007

Complementary to a measurement campaign of small surface targets in the False Bay, South Africa [1], a set-up could be arranged of atmospheric propagation experiments. This opportunity allowed us to collect another set of transmission data in a coastal area, where the environmental conditions are generally non-homogeneous and rapidly changing....

Measurement of optical refraction-, transmission- and turbulence effects in the False Bay, South Africa; June 2007

Complementary to a measurement campaign of small surface targets in the False Bay, South Africa [1], a set-up could be arranged of atmospheric propagation experiments. This opportunity allowed us to collect another set of transmission data in a coastal area, where the environmental conditions are generally non-homogeneous and rapidly changing....

The use of multi-band transmission data collected at Scripps pier in November 2006 for the investigation of aerosol characteristics

The knowledge of the atmospheric aerosol characteristics is of great importance for the range performance of Infrared and Electro-Optical sensor systems. The composition, the concentration and the size distribution of aerosols determine their scattering behavior as function of wavelength and thus their attenuation of light beams. When studies...

Heat stress in wheat (Triticum aestivum L.): Effects on grain growth and quality traits

Heat stress effects on grain dry mass and quality were studied in spring wheat genotypes (Triticum aestivum L.). Three cultivars were chosen with respect to heat tolerance: Lavett (genotype 1), selected for temperate growing conditions and two CIMMYT cultivars, Ciano-79 (genotype 2) and Attila (genotype 3), respectively heat sensitive and heat...

Investigation of aerosol particle size distributions in the San Diego Bay area by means of multi-band transmissometry

The presence of atmospheric aerosols along the line of sight of infrared and electro-optical sensors greatly determines the range performance of these devices. On the one hand the aerosol particles scatter background (including sun) radiance into the field of view of the sensor, on the other hand they contribute to the atmospheric contrast...

Comparison of the particle size distribution and emissions from heavy-duty diesel engines and gas engines for urban buses

Relative contribution of submicron and supermicron particles to aerosol light scattering in the marine boundary layer

Measurements of the aerosol light scattering coefficient (σsp) at a wavelength of λ - 550 nm were conducted at a coastal atmospheric research station in the east Atlantic Ocean during June 1999. Size distribution measurements between diameters of 3 nm and 40 um (at ambient humidity) were used to derive scattering coefficients from Mie theory....

Electro-optical propagation assessment in coastal environments (EOPACE): Summary and accomplishments

EOPACE (electro-optical propagation assessment in coastal environments) was a 5-yr multinational and interdisciplinary effort to improve the performance assessment for electro-optical (EO) systems operating in coastal environments. The initial results of the EOPACE program include: (1) the parameterization of the surf-zone generated aerosol-size...

Extension of the Navy aerosol model to coastal areas

The performance assessment of electro-optical (EO) systems with propagation prediction codes requires accurate atmospheric models. The model that is most frequently used for the prediction of aerosols and their effect on extinction in the marine atmosphere is the U.S. Navy aerosol model (NAM) (Gathman, 1983). The NAM was developed for open ocean...

Ageing of magnesium; influence of particle size and particle shape

Evaluation of concurrent thermal IR atmospheric propagation and aerosol particle size distribution measurements at Gotland, Sweden

Measurements of spectrally resolved (2-14 pm) thermal infrared atmospheric transmission were made at the Swedish

Aerosol Particle Size Distributions at a Rural Coastal Site

Aerosol particle size distributions were measured on the Swedish island Ostergamsholm, about

Size distributions of bubbles and aerosols

Profiling of aerosol concentrations, particle size distributions and relative humidity in the atmospheric surface layer over the North Sea

Results are presented from measurements in the lower 15 m of the marine atmospheric surface layer. The paper is focussed on the comparison of the profile data obtained with the Rotorod and the optical scatterometer. These instruments are based on different physical principles. Results show that fluctuations of particle total area concentrations...

Protection against toxic compounds: chemical and technological aspects