Bulk solution temperature, effect

The effect of the bulk solution temperature lies primarily in its influence on the bubble content before collapse. With increasing temperature, in general, sonochemical reaction rates are slower. This reflects the dramatic influence which solvent vapor pressure has on the cavitation event the greater the solvent vapor pressure found within a bubble prior to collapse, the less effective the collapse. In fact, one can quantitate this relationship rather well (89). From simple hydrodynamic models of the cavitation process, Neppiras, for example, derives (26) the peak temperature generated during collapse of a gas-filled cavity as... 

Dias RMB, Vieira AJSC (1997) Substituent effect on superoxide elimination from peroxyl radicals of adenine and methylated derivatives. J Photochem Photobiol AChem 117 217-222 Didenko YT, Nastish DN, Pugach SP, Polovinka YA, Kvochka VI (1994) The effect of bulk solution temperature on the intensity and spectra of water sonoluminescence. Ultrasonics 32 71-76 Dillon D, Combes R, McConville M, Zeiger E (1992) Ozone is mutagenic in Salmonella. Environ Mol Mutagen 19 331-337... 

What characterises the different incubation steps is the time required to reach thermodynamic equilibrium between an antibody and an antigen in the standard format of microtitre plates. In fact the volume used in each of the incubation steps has been fixed between 100 and 200 pL to be in contact with a surface area of approx. 1 cm2 where the affinity partner is immobilised. The dimensions of the wells are such that the travel of the molecule from the bulk solution to the wall (where the affinity partner is immobilised) is in the order of 1 mm. It must be taken into account that the generation of forced convection or even of turbulence in the wells of a microtitre plate is rather difficult due to the intrinsic dimensions of the wells [10]. Indeed, even if some temperature or shaking effects can help the mass transport from the solution to the wall, the main mass transport phenomenon in these dimensions is ensured by diffusion. 

Let us summarize here this part of the study, since it is published elsewhere (25). First, it is important to ascertain the fast exchange of the sodium counterions between the bulk solution and the vicinity of the platelets. This is done by checking the effect of temperature on relaxation rates. For instance, for a sample of the Ecca Gum BP bentonite (44.2 mg/mL water) the sodium-23... 

Saturated salt solutions and sulfuric acid solutions establish relative humidity by reducing the vapor pressure above an aqueous solution (a colligative effect). Saturated salt solutions at controlled temperature maintain a constant relative humidity as long as excess salt and bulk solution are present. As water is added or removed from the solution, moisture from the head-space will either condense or evaporate (as appropriate), with subsequent dissolution or precipitation of salt to maintain the equilibrium vapor pressure. Because the degree of vapor pressure depression is dependent on the number of species in solution and, further, since the solubility of most salts is somewhat dependent on temperature, the relative humidity generated is also temperature dependent. Hence, use of the same salt at different temperatures can result in different relative humidities. Refs. can be consulted for specific saturated salt solutions that result in defined relative humidities as a function of... 

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