Reservoir molecules

The flow is induced in the following way. External forces are applied on the particles of each reservoir In order to ke p the average y velocities of the reservoirs constant. The Imposed motion of the reservoirs shears the liquid slab. The work supplied In order to keep the reservoirs moving eventually Is dissipated and heats up the liquid. In order to remove this extra heat from the system the velocities of the reservoir molecules are scaled at each time step so as to keep the average reservoir temperatures constant. The Imposed shear rate Is obviously... 

The release of man-made CFCs in the atmosphere has lead to an increase of chlorine containing reservoir molecules such as CIONO, (chlorine nitrate) and HC1 in the stratosphere. Under normal nonpolar conditions, the reaction between both species is extremenly slow. However in the presence of cold surfaces, the following reactions are believed to occur on the PSCs [33] ... 

Fig. 1. Box model of the middle and lower atmosphere indicating the major removal processes for source molecules carried upward from the surface. The small complement of molecules which actually reach the lower stratosphere then become the precursors for free radical chain carrying reactions which are terminated by radical-radical recombination reactions to form reservoir molecules. Downward transport to the tropopause of these reservoir molecules maintains mass continuity.

In the CO oxidation cycle, hydrogen peroxide, H202, is a reservoir molecule for HO, ... 

First of all, it is important to know that free, ozone-threatening chlorine is not normally present in the stratosphere. Instead, most of the time, it is tied up in chlorine reservoirs containing relatively inactive or inert (at least toward ozone) molecular forms of chlorine. Equations (18.66) and (18.67) show how these reservoir molecules are formed ... 

Chlorine nitrate CIONO2 and bromine nitrate B1ONO2 are important reservoir molecules formed by the chain termination reactions, CIO + NO2 and BrO + NO2, in the CIO and BrOx cycles in the stratosphere, respectively. Iodine nitrate IONO2 plays a similar role in the in the iodine chemistry in the troposphere. 

Chlorine peroxide ClOOCl is formed by the termolecular recombination reaction of CIO radicals when the concentration of CIO radicals is high. Among the reservoir molecules in the stratosphere over the Antarctica in wintertime, ClOOCl has the highest concentration, and its photolysis in springtime is very important for the formation of the ozone hole. 

Chlorine dioxide OCIO is formed by the bimolecular cross reactions of CIO by themselves and is a reservoir molecule of chlorine in the stratosphere over wintertime Antarctica the same as ClOOCl. Since OCIO has the strong absorption in the visible region, it is photolyzed instantaneously when the solar light starts to irradiate in spring. 

The reaction of OH radical with nitric acid (HONO2, HNO3) in the stratosphere is important as it reproduces active nitrogen from the reservoir molecule HONO2 in the NOx cycle. Although in the troposphere, water-soluble nitric acid is mainly removed by wet deposition into cloud and fog, and dry deposition on earth s surface, the OH reaction as well as photolysis are also important as removal processes and as active nitrogen regenerating process in the upper troposphere where clouds are not abundant. 

The time dependent relaxation of the hot atom momentum distribution is followed with the aid of the Boltzmann equation. We begin with the formulation of the laboratory momentum distribution for hot atoms (a) undergoing relaxation in a bath of pure reservoir molecules (r) that are in thermal and mechanical equilibrium with each other and with their surroundings. For simplicity the reservoir species are assumed to be initially present in a single quantum state designated by subscript J. 

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