Primary and secondary emissions

Step 1 Determine primary emission heat content. This step should be taken early in the design stage to determine if the enclosure will capture both primary and secondary emissions. The heat content of furnace emissions and the temperature limitation on the fume collector are considered for this task. The off-gas heat content is calculated for furnace reactions during melting and refining periods. The maximum heat content should be used for design. Assuming a fabric... 

For the remaining steps, a small, low-production furnace is under consideration with both primary and secondary emissions being captured by the enclosure. 

If CMBs can be used to distinguish between primary and secondary emissions from coal-fired plants, the results can be used in hybrid receptor models to determine important parameters such as distance scales for transport and transformation of S species. 

Fig. 6 Influence of test conditions on primary and secondary emission (substrate-adhesive-flooring material)...

Fig. 1.7. Instantaneous spectrum of the GC-AED photodiode array wavelength rang for tin detection, showing primary and secondary emissions. (Reproduced by permission from R.L. Firor, American Lo6., 1989, 21(5), 1989 copyright, 1989, International Scientific Communications, Inc.)...

Nonferrous metallurgy is as varied as the ores and finished products. Almost every thermal, chemical, and physical process known to engineers is in use. The general classification scheme that follows gives an understanding of the emissions and control systems aluminum (primary and secondary), beryllium, copper (primary and secondary), lead (primary and secondary), mercury, zinc, alloys of nonferrous metals (primary and secondary), and other nonferrous metals. 

Cell type Emissions with primary and secondary control ... 

Because the various types of particle can appear in both primary excitation and secondary emission, most authors and reviewers have found it convenient to group the techniques in a matrix, in which the columns refer to the nature of the exciting particle and the rows to the nature of the emitted particle [1.1-1.9]. Such a matrix of techniques is given in Tab. 1.1., which uses the acronyms now accepted. The meanings of the acronyms, together with some of the alternatives that have appeared in the literature, are given in Listing 1. 

A complete inventory analysis is conducted for each segment of the fluid milk supply chain to account for all the resource inputs and the primary and secondary sources of GHG emissions (CO2, CH4, and N2O) to air, water, and soil. The resource inputs include raw materials and energy. Their impact on GHG emissions are secondary sources of GHGs. The primary sources of GHG emissions are associated with farm operations. 

Despite the measurement of the emitted radiation by these means it is still possible for scattered or reflected incident radiation to reach the detector. To prevent this, fluorimeters require a second monochromating system between the sample and the detector. Many simple fluorimeters use filters as both primary and secondary monochromators but those instruments that use true optical monochromators for both components are known as spectrofluo-rimeters. Other instruments incorporate a simple cut-off filter system for the emitted radiation while retaining the optical monochromator for the excitation radiation. Because the wavelengths of both excitation and emission are characteristic of the molecule, it is debatable which monochromator is the most important in the design of a fluorimeter. 

Equation (4) states that, to quantify the combustion efficiency, the volume fractions of carbon monoxide and the total hydrocarbon (methane equivalents), the mass flow and the stoichiometry of conversion gas, and the volume flows of primary and secondary air need to be measured. The concept of combustion efficiency is a function of emissions, air dilution, and type of fuel. This concept can be applied to any type of continuous combustion system and any type of fuel. 

The relative contribution of primary and secondary carbon to urban aerosol is discussed in this paper. Some data from the ACKEX study in Los Angeles have been reexamined using new values for the carbon and lead emissions. Data on total carbon, elemental carbon and lead in fine particle samples collected in St. Louis are presented. Lead and elemental carbon have been shown to be useful tracers of primary carbonaceous aerosol. It is concluded that secondary carbon is most likely to be a significant portion of the urban carbonaceous aerosol in the summer and in the middle of the day. Secondary carbon can best be measured with short time resolution sampling (At 6h). 

From a detailed knowledge of the emissions, topography, meteorology, chemistry, and deposition processes, one can develop mathematical models that predict the concentrations of primary and secondary pollutants as a function of time at various locations. Depending on the particular model, these may describe pollutant concentrations over a variety of scales ... 

Particles may be either directly emitted into the atmosphere or formed there by chemical reactions we refer to these as primary and secondary particles, respectively. The relative importance of primary and secondary particles will clearly depend on the phenomena examined, the geographical location with its particular mix of emissions, and the atmospheric chemistry. 

The light, hv2, from F2 is of longer wavelength than hvx from F and is more efficiently detected by a PMT. Two widely used primary and secondary fluors are 2,5-diphenyloxazole (PPO) with an emission maximum of 380 nm and l,4-bis-2-(5-phenyloxazolyl)benzene (POPOP) with an emission maximum of 420 nm. 

Verma et al. [15] have shown for Los Angeles in summer that both primary and secondary particles possess high redox activity however, photochemical transformations of primary emissions with atmospheric aging enhance the toxicological potency of primary particles in terms of generating oxidative stress and leading to subsequent damage in cells. 

The fluorescence quenching experiments of aromatic hydrocarbons by tertiary amines, including /V,/V-dialkylanilincs, in less polar solvents show the typical exciplex emissions [382-384], but products are not obtained or inefficiently produced. On the other hand, in polar solvents such as acetonitrile or methanol, the photoinduced electron transfer from the amines to Aril efficiently occurs to give the addition products. Interestingly, some primary and secondary aliphatic and aromatic amines caused the photoinduced electron transfer even in nonpolar solvents. 

The EPA regulates aluminum and certain aluminum compounds under the Clean Air Act (CAA). They are not, however, designated as hazardous air pollutants (HAPs). The two stationary source categories for which EPA has promulgated performance standards in an effort to control emissions to the atmosphere are primary and secondary aluminum plants (EPA 1977a, 1982a). 

Both primary and secondary electron models (Atoyan Voelk 2000, Brunetti et al. 2001, Blasi Colafrancesco 1999, Miniati et al. 2001) have been analyzed to reproduce the spectral and spatial features of the EUV excess in Coma without a definite solution. Additional experimental information has been recently added to the complexity of the problem in particular, the EUV intensity distribution seems to be highly correlated with the thermal X-ray intensity and produce a constant ratio between the azimuthally averaged EUV and X-ray intensifies (Bowyer et al. 2004). Specific secondary models seem, at present, one of the few viable possibilities to reproduce the EUV emission features of Coma. 

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