Primary Organic Carbon

Primary carbonaceous particles are produced by combustion (pyrogenic), chemical (commercial products), geologic (fossil fuels), and natural (biogenic) sources. Rogge et al. 

Vehicle Sample Size Fuel Consumed FTP, mi gal-1 OC Emission, mg (C)km-1 EC Emission, mg (C)km-1 Total Particulate Emission, mg km-1 

Global primary OC emissions for 1996 were estimated as 17-77Tgyr-1 (Bond et al. 2004), with open burning contributing around 75% of this total, while fossil fuel combustion was estimated at 7%. 

TABLE 14.6 Fine (Dp 2 un) Particle Mass Emissions during Meat Cooking 

Wood combustion has been identified as a source that can contribute significantly to atmospheric particulate levels (Core et al. 1984 Ramdahl et al. 1984b Sexton et al. 1984 Standley and Simoneit 1987 Hawthorne et al. 1992). Fine-particle emission rates reported by Hildemann et al. (1991a) are shown in Table 14.7. 

Hildemann et al. (1991a) measured fine particle emissions from 15 different automobiles and trucks using the cold start Federal Test Procedure (FTP) to simulate urban driving conditions (Table 13.5). The reader should note that this is a very limited sample and such results should be extrapolated with caution to other situations. The noncatalyst automobiles 

There is strong evidence that plant leaves contribute a significant amount of leaf wax as primary organic aerosol particles (Simoneit, 1977, 1986, 1989 Gagosian et al., 1982 Simoneit and Mazurek, 1982 Wils et al., 1982 Doskey and Andren, 1986 Standley and 

TABLE 13.6 Fine Dp 2 jini) Aerosol Mass Emissions During Meat Cooking 

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The quantity of primary production that is exported from the upper ocean is said to be equivalent to new production (18, 19) New primary production is that associated with allocthonous nutrients (i.e., those upwelled or mixed into the euphotic zone or input via rivers and rain). In order for steady state to be maintained, an equivalent flux out of the euphotic zone is required. Earlier studies (19) suggested that sediment-trap measurements of particulate organic carbon (POC) flux were equivalent to new primary production however, recently it has become clear that these measurements probably represent only a... 

The annual primary production of organic carbon through photosynthesis is on the order of 70 Pg/yr. The major part of this carbon is decomposed or respired in a process that also involves the biogeochemical transformation of nitrogen, sulfur, and many other elements. Only a small part of the annual primary production of organic carbon escapes decomposition and is buried in marine sediments. On average. 

Sediment trap studies in the open ocean show that the flux of organic carbon at any depth is directly proportional to the rate of primary productivity in the surface water and inversely proportional to the depth of the water column (Suess, 1980) ... 

Fig. 10-15 Organic carbon fluxes with depth in the water column normalized to mean annual primary production rates at the sites of sediment trap deployment. The undulating line indicates the base of the euphotic zone the horizontal error bars reflect variations in mean annual productivity as well as replicate flux measurements during the same season or over several seasons vertical error bars are depth ranges of several sediment trap deployments and uncertainities in the exact depth location. (Reproduced with permission from E. Suess (1980). Particulate organic carbon flux in the oceans - surface productivity and oxygen utilization, Nature 288 260-263, Macmillan Magazines.)...

The two prime mechanisms of carbon transport within the ocean are downward biogenic detrital rain from the photic zone to the deeper oceans and advection by ocean currents of dissolved carbon species. The detrital rain creates inhomogeneities of nutrients illustrated by the characteristic alkalinity profiles (Fig. 11-9). The amount of carbon leaving the photic zone as sinking particles should not be interpreted as the net primary production of the surface oceans since most of the organic carbon is recycled... 

Water for injection (WFI) is the most widely used solvent for parenteral preparations. The USP requirements for WFI and purified water have been recently updated to replace the traditional wet and colorimetric analytical methods with the more modern and cost-effective methods of conductivity and total organic carbon. Water for injection must be prepared and stored in a manner to ensure purity and freedom from pyrogens. The most common means of obtaining WFI is by the distillation of deionized water. This is the only method of preparation permitted by the European Pharmacopoeia (EP). In contrast, the USP and the Japanese Pharmacopeias also permit reverse osmosis to be used. The USP has also recently broadened its definition of source water to include not only the U.S. Environmental Protection Agency National Primary Drinking Water Standards, but also comparable regulations of the European Union or Japan. 

The primary active surface that interacts with the chemical in the sorption process has been shown to be the organic fraction of the soil(6-10). Therefore, the sorption characteristics of a chemical can be normalized to obtain sorption constant based on organic carbon (K ) which is essentially independent of any soil. 

The Level I calculation suggests that if 100,000 kg (100 tonnes) of benzene are introduced into the 100,000 km2 environment, 99% will partition into air at a concentration of 9.9 x 10-7 g/m3 or about 1 pg/rn3. The water will contain nearly 1% at a low concentration of 4 pg/rn3 or equivalently 4 ng/L. Soils would contain 5 x 10-6 pg/g and sediments about 9.7 x 10 6 pg/g. These values would normally be undetectable as a result of the very low tendency of benzene to sorb to organic matter in these media. The fugacity is calculated to be 3.14 x 10-5 Pa. The dimensionless soil-water and sediment-water partition coefficients or ratios of Z values are 2.6 and 5.3 as a result of a Koc of about 55 and a few percent organic carbon in these media. There is little evidence of bioconcentration with a very low fish concentration of 3.0 x FT5 pg/g. The pie chart in Figure 1.7.6 clearly shows that air is the primary medium of accumulation. 

Phytoplankton as test organisms in toxicity bioassays with surfactants Microalgae are the basis of the aquatic trophic chain and at least 30% of the organic carbon planetary primary production is attributed to... 

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