Water standard pattern analyses

For the confirmatory procedure, it is recommended that the sponsor develop spectral data based on at least three structurally specific ions that completely define the marker residue molecule. These ions may or may not include the molecular ion. The use of water loss and isotopic ions is usually unacceptable and CVM concurrence should be sought when water loss ions or isotopic ions are selected for the confirmatory analysis. The proposed fragment ion structures should be consistent with the fragmentation pattern, and justification for specificity of selected ions or scan range should be included. All confirmation criteria should be specified in the standard operating procedure. 

Materials. Na-Kaolinite A homoionic sample of kaolinite was prepared from a well-crystallized sample purchased from Source Clays, University of Missouri, using a standardized technique (14) which involved repeated washing with distilled water and by treatment with NaCl solutions to remove exchangeable ions such as Ca, and freeze-drying of the final product. Nitrogen specific surface area of this kaolinite was estimated to be 9.4nr/g and X-ray analysis showed the characteristic pattern of kaolinite. 

In some wells, it is possible to obtain an indication of downhole corrosion by analysis of produced fluids for iron. This method is described in NACE Standard Practice for Monitoring Corrosion in Oil and Gas Production with Iron Counts (RP0192). It has been used effectively for monitoring inhibition in wells where corrosion follows a general, nonlocalized pattern, and where the corrosion products are water-soluble (e.g., in sweet wells). 

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