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Laboratory model, photo

FIGURE 3.17 Typical device (Eppley Laboratories Model 8-48) used to measure solar irradiance. The detector consists of a differential thermopile with the hot junction receivers blackened with flat black coating and the cold junction receivers whitened with BaS04 (photo supplied courtesy of G. L. Kirk, Eppley Laboratories). [Pg.61]

Figure 17. Photo of laboratory model control station... Figure 17. Photo of laboratory model control station...
We discuss in this section four key aspects of heterogeneous reactions (1) theoretical and experimental structure and reactivity relationships (2) held measurements of relative and absolute PAH decay rates in near-source ambient air and during downwind transport (3) laboratory studies of the photolysis/photo-oxidation and gas-particle interactions with 03 and NOz of key 4- and 6-ring PAHs adsorbed on model substrates or ambient aerosols and (4) environmental chamber studies of the reactions of such PAHs associated with several physically and chemically different kinds of combustion-generated aerosols (e.g., diesel soot, wood smoke, and coal fly ash). Where such data are available, we also briefly consider some toxicological ramifications of these reactions. [Pg.505]

Bopp L, Boucher O, Aumont O, Belviso S, Dufresne JL, Pham M, Monfray P (2004) Will marine dimethylsulfide emissions amplify or alleviate global warming A model study. Can J Fish Aquat Sci 61 826-835 Bouillon RC, Miller WL (2004) Determination of apparent quantum yield spectra of DMS photo-degradation in an in situ iron-induced Northeast Pacific Ocean bloom. Geophys. Res. Lett. 31 Article no. L06310 Bouillon RC, Miller WL (2005) Photodegradation of dimethyl sulfide (DMS) in natural waters Laboratory assessment of the nitrate-photolysis-induced DMS oxidation. Environ Sci Technol 39 9471-9477... [Pg.272]

In addition to SO2 self-shielding many other possible sources of S-MIF can be identified. The model A S/results for the case of a I0W-O2 atmosphere (e.g.. Figure 5.7b) are in qualitative but not quantitative agreement with the ancient rock record. Elemental S, derived from S(D, is predicted here to have > 0 and < 0, which is consistent with observations of most pyrites [4], but the magnitude of the A S/A S ratio is about a factor of 2 to 3 too high ( -2.5 vs. 0.9). This is a significant discrepancy, and may indicate that MI processes in addition to SO2 photodissociation are at work. One such MI process almost certain to be important in a I0W-O2 atmosphere is SO photodissociation. Isotope-selective photolysis will occur in SO at wavelengths 190-230 nm, but rotationally-resolved spectra, either laboratory or synthetic, are needed to estimate the MI effect. In addition to S-MIF due to SO photolysis, SO2 photoexcitation ( 280-330 nm) and SO3 photolysis [18] must also be considered as possible contributors to S-MIF in the ancient atmosphere. S-MIF due to these photo-processes will be considered in future work. [Pg.71]

Laboratory data on the kinetics, reaction mechanisms and pathways of elementary reactions occurring in the atmosphere form the basis for models describing and predicting photo-oxidant formation. Experience in the incorporation of the chemical information into the models by the Chemical Mechanism Working Group (CMWG) has shown that critical evaluation of currently used chemistry is required. In this respect, a successful exercise was the evaluation and improvement carried out by LACTOZ of the chemistry contained within the EMEP MSC-W model of photo-oxidants. [Pg.11]

This high reactivity towards the important atmospheric photo-oxidants, probably valid also for similar isoprene oxidation products like unsaturated hydroxy carbonyls, hydroxy nitrates or hydroxy hydroperoxides, is an indication that these reactions need more consideration in laboratory experiments as well as photooxidation models. [Pg.86]

The photos show what we see in the laboratory. The ribbon of magnesium metal (left) is surrounded by oxygen in the air, and as it bums, an intense flame is produced. At the end of the reaction, a rather fragile ribbon of white solid, MgO, remains. The models shew the atomic-level view of the reactants and products. [Pg.81]


See other pages where Laboratory model, photo is mentioned: [Pg.380]    [Pg.314]    [Pg.541]    [Pg.149]    [Pg.284]    [Pg.481]    [Pg.106]    [Pg.157]    [Pg.148]    [Pg.248]    [Pg.291]    [Pg.15]    [Pg.317]    [Pg.172]    [Pg.55]    [Pg.43]    [Pg.626]    [Pg.350]    [Pg.50]    [Pg.27]    [Pg.270]   
See also in sourсe #XX -- [ Pg.380 ]




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