-
PREDICTED
Hour
(Local Daylight
Time)
Figure 15. Basin-wide average ozone concentrations in Los Angeles predicted by the carbon-bond mechanism (for two sets of initial pollutant concentrations) and measured on August 4, 1975
available photochemical kinetic mechanisms are sufficiently developed for most practical applications to the atmosphere. T o this end, we believe that the carbon-bond mechanism offers advantages in realism and ease of application. These advantages include carbon mass conservation, elimination of assumptions concerning average molecular weights, reduction of the span of rate constants covered by each grouped species, and reduced computing requirements. Whatever the particular needs of any modeling application, these are factors that should a t least be considered.
Acknowledgment We thank Marcia C. Dodge of the Environmental Protection Agency for many helpful discussions and advice in the review of this manuscript. We are also indebted to Mark Meldgin and Caroline Cochran for their editorial assistance. Literature Cited (1) Whitten, G. Z.; Hogo, H. “Mathematical Modeling of Simulated Photochemical Smog”, Systems Applications, Inc., San Rafael, Calif., EPA-600/3-77-011. (2) Benson, S. W. “Thermochemical Kinetics”; Wiley: New York, 1968. (3) Greiner, N. R. J . Chem. Phys. 1970,53, 1070-1076. (4) Hecht, T. A.; Seinfeld, J. H.; Dodge, M. C. Enuiron. Sci. Technol.
1974,8, 327-339. ( 5 ) Demerjian, K. L.; Kerr, J. A,; Calvert, J. G. In “Advances in Environmental Science Technology”, Pitts, J. N., Metcalf, R. L., Eds.; Wiley: New York, 1974. (6) Niki, H.; Daby, E. E.; Weinstock, B. Adu. Chem. Ser. 1972, No. 113. (7) Chameides, W. L.; Walker, J. C. G. J . Geophys. Res. 1973, 78, 8751-8760. (8) Graedel. T. E.: Farrow. L. A.: Weber. T. A. Enuiron. Sci. Technol. 1977,11, 690-694. (9) Hampson, R. F.; Garvin, D. Nutl. Bur. Stand. ( U S . ) ,Tech. Note 1975. No. 866. (10) Hknpson,R. F.;Garvin,D. Natl. Bur. Stand. (U.S.),Spec. Publ. 1978, No. 513. (11) Nlki, H., et al. Chem. Phys. Lett. 1977,45, 564-566. (12) Graham, R. A.; Winer, A. M.; Pitts, J. N., Jr. Chem. Phys. Lett. 1977,51, 215-220. (13) Cox, R. A. J . Photochem. 1974,3, 291-304. (14) Cox, R. A. Int. J . Chem. Kinet. 1975, S y m p . No. 1, 379-398. (15) Atkinson, R.; Hansen, D. A,; Pitts, J. N., Jr. J . Chem. Phys. 1975, 62, 3284-3288. (16) Cox, R. A.; Derwent, R. G. J . Photochem. 1975,4, 139-153. (17) Hamilton, E. J., Jr.; Lii, R. R. Int. J . Chem. Kinet. 1977, 9, 875-885. (18) Calvert, J. G. Enuiron. Sci. Technol. 1976,10, 256. (19) Whitten, G. Z., et al. “Modeling of Simulated Photochemical Smog with Kinetic Mechanisms”, Vol. I and 11,Systems Applications, Inc., San Rafael, Calif., 1979, EPA-600/3-79-001a, NTIS No. PB-290 507, PB-290 508. (20) Davis, D. D., private communication with Dr. M. Dodge of EPA, 1976. (21) Davis, D. D.; Heaps, W.; McGee, T. Geophys. Res. Lett. 1976, 3, 331-333. (22) Herron, J. T.; Penzhorn, R. D. J . Phys. Chem. 1969, 73, 191196. (23) Morris, E. D., Jr.; Niki, H. J . Chem. Phys. 1971, 55, 19911992. (24) Volman, D. H.; Gorse, R. A. “Photochemistry of the Gaseous Hydrogen Peroxide-Carbon Monoxide Systems: Rate Constants for Hydroxyl Radical Reactions by Competitive Kinetics”, University of California, Davis, Calif., 1972, Final Report, Project 5143-2. (25) Chan, W. H., et al. Enuiron. Sci. Technol. 1976,10, 674-682. (26) Finlayson, B. J.; Pitts, J. N., Jr. Science 1976,192, 111-119. (27) Whitten, G. Z.; Meyer, J. P. “CHEMK: A Computer Modeling Scheme for Chemical Kinetics”. Svstems ADDlications.~,Inc.. San Rafael, Calif., 1976, CS75-70. (28) Anderson, G. E.. et al. “Air Qualitv in the Denver MetroDolitan Region: 1974-2000”, Systems Applications, Inc., San Rafael; Calif., 1977, EPA-908/1-77-002. (29) Tesche. T. W.: Burton. C. S. “Simulated ImDact of Alternative Emissions Control Strategies on Photochemical Oxidants in Los Angeles”, Systems Applications, Inc., San Rafael, Calif.. 1978. EF78-22R. (30) Seinfeld, J. Enuiron. Sci. Technol. 1977,11, 248. I
