Aerosols are harmful to human health and have both direct and indirect effects on climate. China is a major contributor to global emissions of sulfur dioxide (SO2), a sulfate (SO4 2 ) precursor, organic carbon (OC), and black carbon (BC) aerosols. Although increasingly examined, the effect of present and potential future levels of these emissions on global premature mortality and climate change...

Franzinite, ideally [(Na,K)30Ca10][Si30Al30O120](SO4)10•2H2O, a feldspathoid belonging to the cancrinite group, has a tenlayer stacking sequence. Its structure was solved in the space group P321 to an R value of 5.96%. Cell parameters are a 12.916(1), c 26.543(3) Å. The framework, characterized by the stacking sequence ABCABACABC, contains regular alternations of two “cancrinite” and two “sodal...

A large number of studies have indicated associations between particulate air pollution and adverse health outcomes. Wintertime air pollution in particular has been associated with increased mortality. Identification of causal constituents of inhalable particulate matter has been elusive, although one candidate has been the acidity of the aerosol. Here we report measurements of acidic aerosol s...

Water-soluble inorganic ions in aerosol samples have been studied. The sample collection took place during summer in 2003 at a European background site which is operating within the framework of the European Monitoring and Evaluation Program. Gent type PM10 stacked filter unit (SFU) samplers were operated in parallel on a day and night basis to collect particles in separate coarse (2.0-10 micro...

altogether 20 groundwater samples were collected around the lakan pb and zn mine in iran. samples were analyzed for 8 constituents including fe, pb, hg, mn, zn, cn, so4 and cl using standard method. the results show that the average concentrations of constituents were 0.01, 0.60, 0.10, 0.01, 0.40, 35, 0.01 and 5.95 mg/kg for fe, mn, pb, zn, hg, so4, cn and cl, respectively. the computed contami...

Introduction: The Mars Exploration Rover (MER) missions have stimulated considerable thinking about the surficial geochemical evolution of Mars [1-4]. Among the major MER findings is the presence of the mineral, jarosite (a ferric sulfate salt), which suggests formation from an acid-sulfate brine. The objectives of this work were to (1) add ferric iron chemistry to an existing ferrous iron mode...

An ambient particle monitoring study was conducted in Washington, D.C. during the summer of 1994 as part of the Metropolitan Acid Aerosol Characterization Study (MAACS). Acid aerosol and inhalable (particulate matter with aerodynamic diameters < 10 micron; PM10) and fine (particulate matter with aerodynamic diameters < 2.5 micron; PM2.5) particle samples were collected for 24-hr periods (9 A.M....

Pertussis toxin (Ptx) expression and secretion in Bordetella pertussis are regulated by a two-component signal transduction system encoded by the bvg regulatory locus. However, it is not known whether the metabolic pathways and growth state of the bacterium influence synthesis and secretion of Ptx and other virulence factors. We have observed a reduction in the concentration of Ptx per optical ...