Carbon aerosols

Considerable developmental effort is being devoted to aerosol formulations using the compressed gases given in Table 4. These propellants are used in some food and industrial aerosols. Carbon dioxide and nitrous oxide, which tend to be more soluble, are often preferred. When some of the compressed gas dissolves in the product concentrate, there is partial replenishment of the headspace as the gas is expelled. Hence, the greater the gas solubiUty, the more gas is available to maintain the initial conditions. 

Acroldn concentration, 186,187 Adenosine triphosphate, effect of ozone on lung concentration of, 354 Aerosol carbon balance, 50 Aerosol formation, 4, 14, 674-76 ability index, 61 diemical medianisms of, 72 hydrox]4 radical-aromatic hydrocar> bon reaction, 76-81 ozone-olefin reaction, 72-76 condensable species vapor pressure and, 86-90,101... 

Although carbon has long been recognized as an important constituent of ambient aerosols, the analysis of carbon in its many molecular forms has presented formidable obstacles. An approach taken by many investigators (1-12) has been to separate aerosol carbon into organic, elemental, and carbonate classes. However, at the present time only carbonate carbon has an unequivocal analytical definition. Speciation between organic and elemental car-... 

The carbon analyzer has been used to analyze filters from 42 urban sites and 22 non-urban sites in the United States. These filters were obtained from the National Air Surveillance Network (NASN) filter bank for 1975. Carbon concentrations and mass fractions for Detroit, Michigan, are shown in Figures 5 and 6. Both the organic and elemental carbon concentrations are highly variable, and no seasonal trends are apparent. For this site elemental carbon constituted 38% of total aerosol carbon. Typical values for other sites ranged between 35 and 55%. 

Aerosol carbon concentrations have been measured at two sites in the Los Angeles basin. Samples were analyzed for total carbon content and for elemental carbon content by the Gamma Ray Analysis of Light Elements technique and by several optical methods. Elemental carbon was shown to constitute a substantial fraction of total carbonaceous aerosol mass in the wintertime in Los Angeles. 

Pierson, W.R. Russell, P.A., Aerosol Carbon in the Denver Area in November 1973, Atmospheric Environment. 1979, 13. 1623-1628. 

This was calculated in the same manner as that described by Cass, Boone and Macias (9). The carbon to lead ratio determined from this inventory can be examined for several limiting cases ranging from the output of an automobile using leaded fuel (C/Pb /2) to aerosol in the well mixed LA air basin with significant secondary conversion of carbon (C/Pb>7). This approach assumes, of course, that lead is present only as a primary pollutant. For highway traffic composed of vehicles and fuel types in the same proportions as for the entire urban area, the ratio of aerosol carbon to lead was calculated to be about 4. 

Chen, S.-J., S.-H. Liao, W.-J. Jian, S.-C. Chiu, and G.-C. Fang, Particle-Bound Composition of Polycyclic Aromatic Hydrocarbons and Aerosol Carbons in the Ambient Air, J. Environ. Sci. Health, A32, 585-604 (1997). 

Summaries of the aerosol carbon data obtained as part of the POLTERCAIST I and II conducted at the National Oceanographic and Atmospheric Administration (NOAA) Atmospheric Turbulence and Diffusion Laboratory (ATDL) Walker Branch site near Oak Ridge, TN, in cooperation with NOAA-ATDL and Oak Ridge National Laboratory (ORNL) staff are reported in Tables I and II. Concentrations of... 

Adsorbents, extraction procedures, organic pollutants, 113 Aerosol, problems in measuring, coal combustion, 312-317 Aerosol carbon data, results and discussion, carbon isotope tracers, 270-275... 

Many aerosol materials have been used, and the aerosol material can be specifically chosen to minimize interference with the chemical separation being conducted. Widely used were KC1 aerosols which can easily be generated by sublimation of KC1 from a porcelain boat within a tube furnace. By choosing a temperature between 650°C and 670°C, specially tailored aerosols with a mean mobility diameter of about 100 nm and number concentrations of few times 106 particles/cm3 could be generated. The same technique could be applied to produce MoOj aerosols. Carbon aerosol particles of similar dimensions were generated by spark discharge between two carbon electrodes. 

Diesel engine Gas furnace 80% of aerosol 90% of aerosol carbon ... 

Carvalho A., Putaud J.-P., Toom-Sauntry D., and Puxbaum H. (2001) Results of the Carbon Conference international aerosol carbon round robin test stage I. Atmos. Environ. 35, 2111-2121. 

TABLE 13.1 Estimates of Fuel-Specific Aerosol Carbon Emission Rates (g(C) (kg fuel) )... 

Fig. 10. Seasonal changes in (a) concentrations of total diacids in the Asian aerosol samples and (b) relative abundance of total diacid-carbon in total aerosol carbon.

As seen in Fig. 10b, total diacids accounted for 0.8-6.2% of TC (av. 3.1%, median 3.0%) with a maximum in August. These values are consistent with those (1.1-4.9%, av. 3.2%) reported in the western Pacific at 35°N to 40°S (Sempere and Kawamura, 2003). However, they are three times higher than those (0.18-1.8%, av. 0.95%) obtained in Tokyo (Kawamura and Ikushima, 1993), although a summer time maximum was found in Tokyo. Higher values for Jeju Island indicate that diacid carbon contributes more to the total aerosol carbon possibly due to higher emissions of organic precursor compounds in the source areas than in Tokyo and their subsequent conversion to dicarboxylic acids in the atmosphere. 

Fig. 12. Seasonal changes in the relative abundances of (a) oxalic acid, (b) malonic acid, (c) succinic acid, (d) glutaric acid, (e) adipic acid, (f) azelaic acid, (g) 4-ketopimelic acid, (h) malic acid, (i) phthalic acid, and (j) maleic (hydroxysuccinic) acid in the total aerosol carbon (TC) in the aerosol samples from Jeju Island.

Aerosols Carbon black and fumed silica dusts S/G... 

Butane, Propane, Triethylamine propellant, aerosol paints Dimethyl ether, Isobutane, Propane propellant, aerosols Carbon dioxide, ttl-TrIchloroelhane propellant, paint aerosols Methylene chloride property enhancer, latoi Vicron 15-15 Vicron 25-11 property enhancer, paintsfcoatings Vicron 10-20 Vicron 15-15 Vicron 25-11 Vicron 31-6 Vicion 41-8 Vicron 45-3... 

Aerosols Carbon Cycle Cloud Physics Environmental Geochemistry Greenhouse Warming Research Meteorology, Dynamic (Troposphere) Nitrogen Cycle, Atmospheric Ozone Measurements AND Trends (Troposphere) Radiation, Atmospheric... 

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