Sources and mechanisms

Decomposition Hazards. The main causes of unintended decompositions of organic peroxides are heat energy from heating sources and mechanical shock, eg, impact or friction. In addition, certain contaminants, ie, metal salts, amines, acids, and bases, initiate or accelerate organic peroxide decompositions at temperatures at which the peroxide is normally stable. These reactions also Hberate heat, thus further accelerating the decomposition. Commercial products often contain diluents that desensitize neat peroxides to these hazards. Commercial organic peroxide decompositions are low order deflagrations rather than detonations (279). 

There have been occasions in which relatively large quantities of dioxins were released as the result of chemical or industrial accidents. Explosions at chemical plants in Seveso, Italy, in 1976 and at Bhopal, India, in 1984 are examples of such incidents. High levels of dioxin have also been found in animal feed on a few occasions the source and mechanism of this contamination have not always been clear. 

Source and Mechanism of Action of Antimuscarinic Anticholinergic Drugs... 

Sources and mechanisms of trace element disturbances in uremia Trace metal accumulation/toxicity in uremic and dialysis patients References ... 

Sources and mechanisms of trace element disturbances in uremia... 

There are many types and modifications existing for the evaporation process. The text divides the evaporation process into natural evaporation and man-made evaporation. Please divide the evaporation process into other categories based on energy source and mechanical operation. 

This paper and a companion one (JO) address the general question of 3 the source and mechanism of formaldehyde emission from bonded wood... 

They have the ability to tolerate long periods of desiccation. This makes them able to colonize areas from north to south, with extreme environmental conditions. The main sources and mechanisms other than air pollution that influence the heavy metal content in mosses are ... 

While some sources and mechanisms of combustion-generated air pollution have been the subject of considerable study, other sources are poorly characterized and not very well understood. Examples are ... 

Analysis of RGA results provides a good indication of the sources and mechanisms for the generation of the outgassed materials. Table 6.4 shows RGA data of sealed packages containing various die-attachment materials and processing conditions. ... 

In a major effort to confirm that the source of this ubiquitous Hb adduct is indeed acrylamide and, if so, to determine acrylamide sources and mechanisms of formation, two independent analytical methods (Tareke 2002) were developed. With respect to sources, pre-existing evidence of acrylamide in tobacco smoke, which was reflected in increased levels of the Hb adduct of interest, suggested that acrylamide could be formed during incomplete combustion or heating of organic matter. Also, lower background levels of this Hb adduct were observed in wild animals than in humans and laboratory animals, hypothesized to be due to consumption of unheated food by wild animals. Previous laboratory animal experiments (Tareke 2000) had provided some confirmation that acrylamide is formed in fried rat food by verification of the identity of the marker Hb adduct acrylamide using MS/MS analysis, and by demonstration that the amounts of acrylamide determined in fried feed were correlated with the observed increases in adduct levels. 

Cheung, Y. S., and P. S. Nobel Amino acid uptake by pea leaf fragments. Specificity, energy sources, and mechanism. Plant Physiol. 52, 633 (1973). 

Sometimes, despite extensive corrosion testing, some components of the telecommuiucation cable plant may fail in the field. Often these failures are caused by unforeseen field conditions or by the presence of unexpected corrosives. To establish the source and mechanism of corrosion failure, these components are exposed to simulated field conditions, and the results are compared to the field failures. Some examples of simulated field failures are described below. 

The main differences between these two techniques are their ionization source and mechanism. The photoionization technique is a nondestructive method of detection, while flame ionization method destroys the sampled material. 

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