Aerosols cadmium

Only physisorption is expected between CsOH vapor and cadmium aerosols (which in many accident sequences are a major constituent of the aerosols during the period of cesium evolution from the fuel and of formation of cesium hydroxide) with no chemical interactions predicted (Bowsher, 1987). Beard et al. (19988 b) reported condensation to be the dominant mechanism in this system. 

The possible condensation of Csl onto cadmium aerosols may be an important mechanism for transport and/or attenuation, but no chemical reaction between these two partners is to be expected Beard et al. (1988 b) found only evidence at a microscopic level for a limited chemical reaction at the Cd-Csl interface. 

Beahm, E. C., Weber, C. F., Kress, T. S., Shockley, W. E., Daish, S. R. Chemistry and mass transport of iodine in containment. Proc. 2. CSNI Workshop on Iodine Chemistry in Reactor Safety, Toronto, Can., 1988 Report AECL-9923 (1989), p. 251—266 Beard, A. M., Bowsher, B. R., Nichols, A. L. Interaction of molecular iodine vapour with silver—indium—cadmium aerosol. Proc. International Symposium Severe Accidents in Nuclear Power Plants, Sorrento, Italy, 1988 IAEA-SM-298/108, Vol. 2, p. 201—213 Bell, J. T. Chemistry of iodine and cesium, in M. Silberberg (Report Coordinator) Technical Bases for Estimating Fission Product Behavior during LWR Accidents. Report NUREG-0772 (1981), Chapter 5... 

Air-poUutant effects on neural and sensory functions in humans vary widely. Odorous pollutants cause only minor annoyance yet, if persistent, they can lead to irritation, emotional upset, anorexia, and mental depression. Carbon monoxide can cause death secondary to the depression of the respiratory centers of the central nervous system. Short of death, repeated and prolonged exposure to carbon monoxide can alter sensory protection, temporal perception, and higher mental functions. Lipid-soluble aerosols can enter the body and be absorbed in the lipids of the central nervous system. Once there, their effects may persist long after the initial contact has been removed. Examples of agents of long-term chronic effects are organic phosphate pesticides and aerosols carrying the metals lead, mercury, and cadmium. 

As a rule, simulations consider emissions of heavy metals from anthropogenic and natural sources, transport in the atmosphere and deposition to the underlying surface (Figure 6). It is assumed that lead and cadmium are transported in the atmosphere only as a part of aerosol particles. Besides, chemical transformations of these metals do not change removal properties of their particles-carriers. On the contrary, mercury enters the atmosphere in different physical and chemical forms and undergoes numerous transformations during its pathway in the atmosphere (Ilyn et al., 2002 2004 Ilyin and Travnikov, 2003). 

Towey TF, Khanlodhi A, Robinson BH (1990) Kinetics and Mechanism of Formation of Quantiun-Sized Cadmium-Sulfide Particles in Water Aerosol-Ot Oil Microemulsions. J Chem Soc Faraday Trans 86 3757-3762... 

Thus some generalisations can be made as to the origins of aerosol particles based on their size (Fig. 7.1). Certain metals such as lead and cadmium tend to be associated with small particles as a result of their abundance in high-temperature combustion processes (smelting, incineration, fuel burning, etc.) and their... 

S. Takenaka, H. Oldiges, H. Konig, D. Hochrainer, and G. Oberdorster, Carcinogenicity of cadmium chloride aerosols in Wistar rats. J. Natl. Cancer Inst. 70 367, 1983. 

The haze which can be seen in fair weather is mainly due to submicron ammonium sulphate particles. This aerosol also contains soot, agglomerates of very small carbon particles with adsorbed high molecular weight organic compounds and appreciable amounts of certain trace elements, e.g. lead, zinc, iron, nickel, cadmium etc. 

A in particle size distribution curves. Colloidal gold, silver, platinum and platinized cadmium sulfide were generated in Aerosol-OT reversed micelles or in microemulsions by in situ photolysis of the appropriate ions (Figure 3.15). Under suitable conditions, each assembly contained approximately eight Au " ions, which firstly led to the formation of Aug clusters. ... 

The chemical features of tin(IV) alkoxides, such as pre-existing metal-oxygen bonds in molecular units, high volatility and low decomposition temperatures make them attractive precursors for deposihon of Sn02. The heterometallic complex [Sn(dmae)2Cd(acac)2],Figures.1.2, (acac = 2,4-pentanedionato dmae = N,N -dimethylamino-ethanoate) has been decomposed in aerosol-assisted chemical vapor deposition conditions, producing amorphous tin(IV) oxide films with no detectable cadmium. ... 

Thus there was a significant systemic exposure after inhalation of the aerosolized cadmium oxide. 

Disposition of inhaled cadmium oxide aerosol in the rat. Inhalation Toxicol 6 379-393, 1994. 

Harrison HE, Bunting H, Ordway N and Albrink WS (1947) The effects and treatment of inhalation of cadmium chloride aerosols in the dog. 

Cd has been emitted in greatly increased quantities after 1945 in the form of dusts and aerosols into the atmosphere, effluent into freshwater, and as solids from anthropogenic industrial activities (Stoeppler, 1991). Cd has a relatively high vapor pressure. The vapor is oxidized quickly to produce cadmium oxide in the air. When reactive gases or vapor, such as carbon dioxide, water vapor, sulfur dioxide, sulfur trioxide or hydrogen chloride, are present, the vapor reacts to produce cadmium carbonate, hydroxide, sulfite, sulfate or chloride, respectively. These salts may be formed in stacks and emitted into the environment (WHO, 1992b). 

Cadmium Oxide aerosol. LCgo BP Decomposes VP None... 

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