Aerosol behaviour

A. Jansson. Local exhaust ventilation and aerosol behaviour in industrial workplace air.. rbete och Hdlsa, no. 43, 1990. 

Figure 11. Variation of unattached fraction of potential alpha-energy and equilibrium factor according to a model of room aerosol behaviour and the effect on bronchial dose rate per unit radon gas concentration.

Small amounts of surfactants may be used to prevent aggregation of proteins and may enhance the refolding process when the dried protein dissolves. Buffers may also help to prevent aggregation of the dissolved drug. Similarly, polymers may be used as aggregation inhibitors or to form matrices. Chan et al. [86] prepared crystalline powders of recombinant human deoxyribonuclease with high fractions of sodium chloride. These powders were formulated as adhesive mixtures on lactose and mannitol and showed improved aerosolization behaviour compared to the pure protein. 

Morrow, P.E. Yu, C.P. (1985) Models of aerosol behaviour in airways. In Aerosols in Medicine, Principles, Diagnosis and Therapy, ed. M.T. Newhouse M.B. Dolovich. Amsterdam Elsevier. 

Most research on Po has focussed on its application as a tracer of environmental processes, and its impact on human health through radiation exposureIt has featured particularly prominently in studies of marine sedimentation processes, foodchains, atmospheric circulation and aerosol behaviour. Dosimetric studies have shown it to be the largest contributor of natural radiation dose to marine organismsthrough ingestion, with resulting implications for human radiation exposure, particularly where seafoods are involved ... 

Shekunov, B.Y. Feeley, J.C. Chow, A.H.L. Tong, H.H.Y. York, P. Aerosolization behaviour of micronised and super-critically-processed powders. Aerosol Sci. 2003, 34, 553-569. 

Friedlander, S.K., "Smoke, Dust and Haze, Fundamental of Aerosol Behaviour", Wiley, N.Y., 1977. 

In addition, the cumulative size distribution obtained for pure micron-ized and supercritically produced powders, combined with computation of the aerodynamic diameter according to Eqs. (2) and (3), shows that FPF of supercritically produced particles is about 50%, twice as much as FPF for micronized powder and close to the dispersion efficiency found with lactose (76). The correct values for the total emitted dose of drug particles also were confirmed. In all cases, the state of dispersion for the different formulations was correctly predicted and the results obtained showed good agreement with the cascade impactor measurements made on the same samples. Therefore laser diffraction has distinct advantages over impactor techniques with respect to the speed and reproducibility of measurements and can be used as a complementary method for analysis of aerosol behaviour of different formulations. 

Shekunov BY, Feeley JC, Chow AHL, Tong HHY, York P. Aerosolization behaviour of micronised and supercritically-processed powders. J Aerosol Sci. In press. 

Friedlander, S.K., Smoke, Dust and Haze Fundamentals of Aerosol Behaviour, Wiley-Interscience, New York, 1977. 

In the upper troposphere the size distribution of large and giant particles was investigated by Soviet (Kondratyev et al.. 1969) and American (Blifford. 1970) research workers. Particles were collected by impactors in both cases. Figure 29 shows Blifford s size distributions for different altitudes, obtained over Nebraska, U.S.A. An interesting feature emerging from the distributions presented is the decrease in the steepness of the slope in the distributions (that is the value of fi in equation [4.12] decreases). It is very difficult to explain this peculiarity of aerosol behaviour. However, it is believed that the removal of aerosol particles by cloud elements (Chapter 5) plays an important role in control of the size distribution of aerosol particles in the troposphere. 

Aerosol behaviour in the containment is largely dictated by physical properties including ... 

V-3a. Workshop on Aerosol Behaviour and Thermal Hydraulics in the Containment, Committee on the Safety of Nuclear Installations, OECD Nuclear Energy Agency, Paris, France, 1990, CSNI Report 176. 

Sedimentation velocities of aerosol particles depend on particle shape. The models of aerosol behaviour that are now available are derived for perfect spheres that have no porosity. The deviations of real particles from this ideal are handled by correction factors called shape factors. In the case of gravitational settling, the dynamic shape factor is used to account for deviations from sphericity and for porosity. These shape factors are not known well and frequently are estimated by back calculation from experimental data for simulant aerosols. This, of course, is not a reliable procedure. There have been some attempts to predict shape factors based on the fractal nature of particles that have grown by coagulation [A-7b]. 

Bowsher, B. R. Fission-product chemistry and aerosol behaviour in the primary circuit of a pressurized water reactor under severe accident conditions. Progress in Nuclear Energy 20, 199-233 (1987)... 

Beard, A. M., Benson, C. G., Bowsher, B. R., Dickinson, S., Nichols, A. L. Fission product and aerosol behaviour within the containment. Report AEEW-R 2474 (1989)... 

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