Environmental deterioration analysis

Figure 4.10 Environmental deterioration analysis logic diagram.

John Rosen (419 and 420) claimed that direct analysis (a psychoanalytic-like technique) produced improvement in 37 cases of deteriorated schizophrenia. He defined improvement as the ability to live comfortably outside of an institution, with the achievement of psychological integrity, emotional stability, and character structure such that a patient could withstand as much environmental stress as one who never experienced a psychotic episode. The credibility of this claim, however, was shattered by an independent evaluation of these patients outcome. Five years later, a follow-up of Rosen s group found that 37% had not been initially diagnosed as schizophrenic, but rather as psychoneurotic, manic-depressive, or possibly hyperthyroid (e.g., one patient recovered after her thyroid was removed). The remainder met criteria for schizophrenia, and during the next 10 years, 75% had between two and five subsequent readmissions. Thus, Rosen s initial claims were not substantiated because many did not have schizophrenia, and most of those who did were not able to sustain their improvement. 

The content of contaminants in foods is an altogether more demanding problem since contaminants are often present in trace quantities. Accordingly, it is necessary to resort to the sample preparation and trace enrichment techniques commonly used in environmental analysis. The types of problems that might be encountered include drug residues in meat products, furosine (known for its deteriorative and browning reaction) in... 

The full methodology of retrospective analysis was applied for the case of marble tombstone deterioration in an urban and a remote cemetery near New York City (8,9). In this exercise it was found that our technique may estimate rural SO2 concentrations acceptably well, but it does not reproduce detailed structure of urban concentrations adequately. The main reasons are uncertainty about the effective release heights of sources and a lack of detailed local emission Information. For the purposes of metal corrosion, the current state of the retrospective reconstruction of environmental histories is not sufficiently quantitative to warrant extraction of damage functions. 

The maximum performance period is the maximum practical amount of time expected from a given pavement structure or stage construction. Theoretically, the maximum performance period should be equal to the analysis period, but in practice, this rarely happens (taking into consideration the effect of environmental factors, surface deterioration, etc.). 

In this work, the potential for application of Mossbauer spectrometry to corrosion studies was demonstrated for three accelerated corrosion tests in chloride environments. This technique allowed retrieving maximum information from the inherent properties of the rust layers. With VT-MS, it was possible to identify and determine the relative iron phase abundances from which three parameters could be calculated (i) a, (ii) (A + S)/(A + L + S), and (iii) PAI. Moreover, with the physical properties retrieved from the analysis of the hyperfine parameters, it was possible to discuss prospective mechanisms of formation and therefore to contribute to the understanding of the deterioration progress. These studies showed that some corrosion product is lost and/or the conversion of metallic ions into iron oxides may be incomplete, and that the relative iron phase abundances pointed out to a nonprotective and active type of rusts. More work is required on other types and chemistry (composition and abundance of alloying elements) of steels, other environmental conditions, and different exposure times. More efforts are needed to improve the fitting models for nonstoichiometric and substituted iron oxides in rust layers. 

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