Coupled cycles atmosphere

Chameides, W. L. and Stelson, A. W. (1992). Aqueous-phase chemical processes in deliquescent sea-salt aerosols a mechanism that couples the atmospheric cycles of S and sea salt. /. Geophys. Res. 97, 20565-20580. 

See also Hydrologic cycle chemical weathering in, 26 4-7 coupling of atmosphere, land, and water in, 26 7-12... 

Chameides, W. L., and A. W. Stelson, Aqueous Phase Chemical Processes in Deliquescent Sea-Salt Aerosols A Mechanism That Couples the Atmospheric Cycles of S and Sea Salt, J. Geophys. Res., 97, 20565-20580 (1992b). 

A synthetic coupled cycle of calcium and carbon through the oxalate-carbonate pathway is shown in Fig. 12.8. Atmospheric CO2 is fixed by the plants through photosynthesis to produce biomass. Inside the plant, oxalate crystals form. In addition, fungal mycelium may also accumulate oxalate. Mainly in the form of calcium oxalate (COM or COD), this carbon pool is used by oxalotrophic bacteria as a carbon, energy and electron source. The transformation of oxalate can occur in the soil... 

A mechanism that couples the atmospheric cycles of S and sea salt. J Geophys Res 97 20565-20580 Chameides WL, Lindsay RW, Richardson J, Kiang CS (1988) The role of biogenic hydrocarbons in urban photochemical smog Atlanta as a case study. Science 241 1473-1475 Charlesworth DH, Marshall WR (1960) Evaporation from drops containing dissolved sohds. Am Inst Chem Engin J 6 9-23... 

The reactions of the ozone cycle account for some, but not all, of the facts about the ozone layer. Many chemical reactions occur that involve substances other than oxygen. We must also consider the effects of turbulence and winds that mix up the stratosphere. A complicated picture results. The overall result of ozone formation and removal reactions, coupled with atmospheric turbulence and other factors, is to produce the upper-atmosphere ozone profile shown in FIGURE 18.4, with a maximum ozone concentration occurring at an altitude of about 25 km. This band of relatively high ozone concentration is referred to as the ozone layer or the ozone shield. ... 

Scheme 78) [89]. Aryl chlorides with activating as well as deactivating substituents could also be coupled under the same conditions in high yields, ranging from 60% to 95%, within 30-60 min of microwave irradiation. The process does not require an inert atmosphere. The increased conversion observed with the addition of the ionic liquid reveals that it might have an additional function besides simply acting as a molecular irradiator . It cannot be excluded for instance that carbene palladium complexes are formed in situ and implicated in the catalytic cycle. 

An important class of cycles with non-linear behavior is represented by situations when coupling occurs between cycles of different elements. The behavior of coupled systems of this type has been studied in detail by Prigogine (1967) and others. In these systems, multiple equilibria are sometimes possible and oscillatory behavior can occur. There have been suggestions that atmospheric systems of chemical species, coupled by chemical reactions, could exhibit multiple equilibria under realistic ranges of concentration (Fox et ai, 1982 White, 1984). However, no such situations have been confirmed by measurements. 

The cycles of carbon and the other main plant nutrients are coupled in a fundamental way by the involvement of these elements in photosynthetic assimilation and plant growth. Redfield (1934) and several others have shown that there are approximately constant proportions of C, N, S, and P in marine plankton and land plants ("Redfield ratios") see Chapter 10. This implies that the exchange flux of one of these elements between the biota reservoir and the atmosphere - or ocean - must be strongly influenced by the flux of the others. 

Tajika, E. (1992) Evolution of the atmosphere and ocean of the Earth global geochemical cycles of C,H,0,N, and S, and degassing history coupled with thermal history. Doctoral Thesis, University Tokyo, 416 pp. 

Coupling of organostannanes with halides in a carbon monoxide atmosphere leads to ketones by incorporation of a carbonylation step.249 The catalytic cycle is similar to that involved in the coupling of alkyl or aryl halides. These reactions involve Reactions involving a migration of one of the organic substituents to the carbonyl carbon, followed by... 

The research published in this book uses the presently most comprehensive multicompartment model, the first which comprises a coupled atmosphere-ocean general circulation model (GCM). GCMs are the state-of-the-art tools used in climate research. The study is on the marine and total environmental distribution and fate of two chemicals, an obsolete pesticide (DDT) and an emerging contaminant (perflu-orinated compound) and contains the first description of a whole historic cycle of an anthropogenic substance, i.e. from the introduction into the environment until its fading beyond phase-out. 

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