New Standardization Technique for X-Ray Absorption Measurements

>Tests of previously suggested methods of determining uranium in solution by x-ray absorption indicated that daily calibration of the photometer is necessary because of changes in response. It was found that by using machined aluminum plates as standards rather than uranium solutions, the time necessary for daily calibration can be reduced to about 15 minutes. The method was found to have a limit of error of plus or minus 0.25% at the 95% confidence level for a single determination of uranium in a solution equivalent to about 30 milligrams uranium dioxide per gram of solution. It was found difficult to obtain cells matched for x-ray absorption work, a point that has been insufficiently stressed in the past. (auth)