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Accurate quantifications of aerosol components are crucial to predict global atmospheric transport models. Recently developed International Monitoring System (IMS) network represents an opportunity to enhance comprehensive systematic aerosol observations on a global scale because it provides a global infrastructure. As such, a local pilot study utilizing several state-of-the-art instruments has been conducted at the peak of the Rattlesnake Mountain, Washington, USA, during three month periods (June-August) in 2003 to explore this opportunity. In this study, routine aerosol samples were collected using a 3-stage Cascade Impactor Beam Analyzer (0.07 to 2.5 µm) with time resolution about 6 hours on long Teflon strips while radionuclide aerosols were collected using Radionuclide aerosol sampler/analyzer (RASA) developed at Pacific Northwest National Laboratory. The elemental composition and hydrogen concentration were measured using proton induced x-ray emission (PIXE) and proton elastic scattering analysis (PESA), respectively. In addition, short and long-lived radionuclides that exist in nature were measured with same time resolution (6 hours) using RASA. In this method, high-resolution gamma-ray spectra were analyzed for radionuclide concentration. Combination of trace radioactive and non-radioactive element analysis in aerosols makes this investigation unique.

The size distributions of mass concentrations for 18 elements were obtained from a PIXE analysis of the atmospheric aerosol around the Great Wall Station in the Antarctic. The enrichment factors for various elements in the aerosol relative to the earth crust and sea water with a salinity of 3.5% were calculated. Comparisons were made between the coarse, fine and ultra-fine particles in the aerosol and those over the Pacific and in Beijing.

We observed the following: The atmospheric aerosol around the Great Wall Station comes mainly from marine aerosol, which is chiefly distributed at the particle size range of 0.5–8 μm and, to a lesser extent, from the local soil dust, which is distributed at particle sizes greater than 8 μm. Particles caused by human activities also come up to some proportions, and are distributed at sizes less than 0.5 μm. We conclude from analysis of size distribution spectra for aerosol mass concentrations that ultra-fine anthropogenic particles are mainly transported to the Great Wall Station from distant continents.

Atmospheric aerosol samples were collected with eight-stage cascade impactors at five typical sites in Guangzhou. The samples were analyzed by the proton-induced X-ray emission (PIXE) technique. The mass concentrations and their size distributions for near 20 elements were obtained. Enrichment factors for coarse and fine modes of the elements were calculated. The sources of the elements and characteristics of atmospheric aerosols at Guangzhou were discussed; the results of mass concentrations for 15 elements in atmospheric aerosols were also compared with those in some other cities in China.

Proton Induced X-ray Emission (PIXE) analysis has been performed to determine the longitudinal distribution of coarse- and fine-fraction as well as total aerosol concentrations at ground level in the neighbourhood of a single emission source situated in a valley in complex terrain. Average environmental impact on the quality of air can be guessed by the comparison of the total .concentration data obtained in two sampling stations with those of a reference background sampling station. Transport properties in the terrain were derived by comparing the measured distributions to the one calculated from a simplified version of the Gaussian plume formula apt for modelling short distance transport over a plane area.

Samples of atmospheric aerosol particles collected at various height over a suburban sampling site were analyzed with respect to 13 elements by PIXE method. Concentrations, enrichment factors, and fine-to-coarse concentration ratios of the fractions were obtained by averaging over height distribution. In one of the sampling experiments dry-deposition velocities were deduced for seven elements from the height distribution.

The atmospheric aerosol samples are collected in Beijing using a ten-stage cascade impactor sampler, and the elemental concentrations are analyzed by the PIXE analytical method. The parameters of particle size distributions are determined by the use of log-normal plots and the least-squares minimization. From these parameters the total amount of deposit in a day at the naso-pharyngeal, tracheo-bronchial and pulmonary are evaluated based on the deposition and retention models.

The study of atmospheric aerosols originating from natural and anthropogenic processes is of basic importance for a detailed understanding of the physics and chemistry of the atmosphere. Particle Induced X-ray Emission (PIXE) technique has been used by the authors for studying regularly the elemental composition of rural, suburban, and urban aerosols collected at six sampling sites in Hungary. Observed data presented in terms of concentrations and regional signature values and evaluated wind sector partition and in transport modelling revealed the natural/anthropogenic contribution to the moderate air pollution here. Dry deposition velocities have been deduced for elements V, Cr, Mn, Co, Ni, Cu, Zn, Cd, and Pb. Model calculations based on annual emission data and observed elemental concentrations resulted in total dry and wet deposition masses of the above elements to the territory of the country. At the same time, deduced budget data for the emission and deposition of the constituents indicated whether the country represents a net source or a sink for the above mentioned elements in the regional aerosol transport between neighbouring countries. Evidences have been found for intrusion events of Saharan aerosol to the atmosphere of Hungary. Part of the data collected recently will be evaluated in the frame-work of an international co-ordinated research programme.

Atmospheric aerosol samples were collected using an 8-stage cascade impactor or an automatic time sequence step sampler at Mount Qomolangma and Beijing. Element concentrations were analyzed by particle induced x-ray emission (PIXE) technique. Then the data were analyzed by the absolute principal factor analysis (APFA) to evaluate the principal components and the percent variance explained by them. As a result, it shows that the PIXE analysis combing with statistical method can effectively resolve the aerosol components in urban area and distinguish between local and remote area aerosol components in the area far from the pollution sources.

The formation of new atmospheric particles by gas-to-particle conversion leads to enhanced concentrations of nanoparticles. We have studied the formation and growth of new particles in urban Atlanta and in the remote atmosphere in locations ranging from the North Pole to Mauna Loa, Tasmania and the South Pole. Key to this work was our development of new measurement techniques for freshly formed nucleation mode particles between 3 and 10 nm. In this paper we show that measured aerosol size distributions in the 3–10 nm diameter range often increase with decreasing size down to our minimum detectable size of 3 nm, presumably because nucleation was occurring during the measurement. Furthermore, we show that the Atlanta nucleation mode size distributions are consistent with a collision-controlled nucleation process in which accommodation coefficients for all collisions between condensing molecules and molecular clusters and between molecular clusters are assumed to be equal to one, and in which evaporation from molecular clusters is neglected, as would be expected for a highly supersaturated vapour.