Interfacial behavior of selected biologically and technologically relevant ions is studied using molecular dynamics simulations employing polarizable potentials. Propensities of choline, tetraalkylammonium (TAA), and sodium cations, and sulfate and chloride anions for the air/water interface are analyzed by means of density profiles. Affinity of TAA ions for the interface increases with their i...

background: air pollution and concerns about health impacts have been raised in metropolitan cities like tehran. trend and prediction of air pollutants can show the effectiveness of strategies for the management and control of air pollution. artificial neural network (ann) technique is widely used as a reliable method for modeling of air pollutants in urban areas. therefore, the aim of current ...

We present results from theoretical studies of aqueous ionic solvation of alkali halides aimed at developing a microscopic description of structure and dynamics at the interface between air and salt solutions. The traditional view has depicted the air/solution interface of simple electrolytes as being devoid of ions. However, it is now firmly established that polarizable anions, such as the hea...

the main objective of a research program, whose output is presented here, has been to estimate “ventilation coefficients”, a critical parameter in determining air pollution concentration near the surface ground which signifies the ability for natural ventilation of an air shed in an urban or rural area. relevant measured data from the city of tehran has been used to calibrate and further de...

although water and land pollution are very dangerous, air pollution has its own peculiarities due to its transboundary dispersion of pollutants over the entire world. in any well planned urban set up, industrial pollution takes a back seat and vehicular emissions take precedence as the major cause of urban air pollution. in the present study, air pollution tolerance index was calculated for var...

Tree planting has been proposed by the municipal government as a measure to alleviate air pollution in Beijing, the capital of China. This study examines that proposal. It is based on the analyses of satellite images and field surveys to establish the characteristics of current urban forest in the central part of Beijing. The influence of the urban forest on air quality was studied using the Ur...

Air quality information such as the concentration of PM2.5 is of great significance for human health and city management. It affects the way of traveling, urban planning, government policies and so on. However, in major cities there is typically only a limited number of air quality monitoring stations. In the meantime, air quality varies in the urban areas and there can be large differences, ev...

considering rapid growth and migration, higher accumulation of communities along with the high number of shopping trips in mega cities such as tehran brings environmental consequences like excessive amounts of energy use, air pollution and massive urban congestions in all urban trips ending to shopping areas. the present study has been performed in tehran, capital of iran in 2009-2010. with the...

background: the activity concentrations of some radionuclides in soil samples collected from 20 locations in 8 major towns in oyo state, southwestern nigeria have been determined by gamma-ray spectrometry technique. materials and methods: the activity concentrations were determined using high-purity germanium (hpge) detector (canberra industries inc.). the outdoor absorbed dose rates in air at ...