The grain size effects on the bremsstrahlung emission spectrum due to nonrelativisitc electrondust grain collisions are investigated in dusty plasmas. Using the Born approximation for the initial and final states of the projectile electron, the bremsstranhlung radiation cross section is obtained as a function of the grain size, dust charge, Debye radius, collision energy, and radiation photon e...

Dechlorane plus (DP), a flame retardant recently identified in the air and sediment of the Great Lakes region, has been detected in residential indoor dust in the city of Ottawa, Canada using gas chromatography-mass spectrometry under negative chemical ionization mode. DP was detected in all dust samples with a concentration range of 2.3 to 182 ng g(-1), except for one dust sample (5683 ng g(-1...

[1] The new Level 3 aerosol profile data derived from the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) provide a multiyear global aerosol distribution with high vertical resolution. We analyzed seasonal and diurnal variations of the vertical distributions of aerosol properties represented by 5-year CALIPSO data. Results show that dust, smoke, and polluted dust ar...

In a recent experiment a wake was created in a two-dimensional lattice of charged dust grains by a charge moving parallel to the lattice plane. Multiple ‘‘Mach cones’’ were observed in the wake. This paper describes a linear theory of the phonon wake caused by a charge moving relative to a crystalline lattice. The theory predicts multiple structures in the wake that are qualitatively similar to...

[1] Recent experimental and modeling studies show that large quasi-static electric fields (2–20 kV/m) can be developed in a Martian or terrestrial dust devil as a result of contact electrification and charge separation of dust grains with different sizes and compositions. Electric discharging occurs when the maximum electric field reaches breakdown values ( 20 kV/m on Mars and 3 MV/m on Earth, ...

The objective of this paper is to study the effect of different plasma and dust parameters on Polar Mesospheric Summer Echoes (PMSE) temporal behavior after turn-on and turn-off of radio wave heating and to use these responses to diagnose the properties of the dust layer. The threshold radar frequency and dust parameters for the enhancement or suppression of radar echoes after radio wave heatin...

The climate–growth relationships and the variation of the radial growth of Oxalis– Myrtillus-site type Norway spruce and Scots pine stands in conditions of different cement dust loads were investigated. The climate–growth relationships were studied during the period from 1946 to 2004. The variation of the mean tree-ring width was studied during three time periods, from 1941 to 1965, from 1966 t...

in this study, the removal of cd(ii) from aqueous solutions have been carried out using populusnigra saw dust as low-cost, readily available biosorbent. various physico-chemical parameters such as ph, initial metal ion concentration, and adsorbent dosage level and contact time were studied at room temperature to optimize the conditions for maximum adsorption. the central composite design was ca...

BACKGROUND In Hawai'i, mortality and morbidity from asthma are significant. In the 80's, there had been no local studies of topography folklore. There had been only one report of seasonal variation in house dust mite (HDM) density in Hawai'i, and this showed no significant variation in O'ahu's Manoa Valley but a definite variation in Waikiki. There were no studies of complete replacement of fur...