Field Signature Method

The field signature method (FSM) is a relatively new mefliod developed by CorrOcean ASA from the principle commonly used in electrical resistance (ER) probes. An electric current is sent through the part of flic installation being tested (often a pipeline), and the potential differences between a considerable number of points on the external surface are measured. The potential differences depend on reduction of the material thickness and how this reduction is distributed along the pipe wall [9.12]. 

This comprises the measurement of the changes in an applied electric field within a pipe spool, caused by the loss of material from the inner wall due to internal corrosion. Field signature methods are commercially available. 

Computer applications allow for defining and managing several important nonclinical data types that are managed by the system itself. Such data are referred to as metadata or control data. These are information such as domain-specific descriptions, application conditions, parameters, and methods in a repository. Control data fields can be part of the data collection forms or in system-defined tables. Some of these control fields include electronic signatures, form status, transmission date, transmission number, field completed, and memo fields (large text format). The database contains tables for reference ranges, visit schedule, form schedule, labels, and drug codes. 

However, not all reactive intermediates are kind enough to provide spectroscopic signatures that allow their immediate and unambiguous identification, and it is therefore often necessary to compare those signatures to ones obtained by means of modeling calculations (the reader may note that with this we leave the realm of forensic analogy that we have perhaps already stretched too far). In fact, many recent matrix isolation studies owe their success to the tremendous advances in the field of computational chemistry, and to the increased availability of the hard- and software required to carry out such calculations. This simation provides an opportunity for much creative work in the field of reactive intermediates, but it also implies an obligation on the part of those who use such methods to apply them with due care and circumspection. 

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