Photographic quantitation in spark source mass spectrography using an on-line densitometer and ion intensity areas

Microphotometer modification for automatic recording of spark source mass spectra

“…The computed normalized abundance data are listed next followed by the error and percent relative error between computed and reported abundance data at the far right of the table. The average relative error of 5.4% and median relative error of 3.6% indicate that relative line intensities are being determined with accuracies very close to limitations imposed by emulsion variations and calibration techniques (1,7). The time required for data recording is of considerable interest.…”

“…Unless standardization techniques are used the area/minima difference will generally introduce much smaller errors than other associated uncertainties such as assumed elemental sensitivities. For quantitative work, line intensity profiles should be constant (6) and if they are constant then transmission minima are accurate indicators of line intensity (1). 4) Background (fog level) reading is recorded as the level of photoplate transmission in a region of the plate selected by the operator.…”

“…Figure 1 is a schematic diagram depicting the construction of the sample tube cracker. The sealed end of a 6-mm quartz or Pyrex sample tube (H) is shown inserted into the cracker 1 Present address, Chemical Evolution Branch, Ames Research Center N239-9, National Aeronautics and Space Administration, Moffett Field, Calif. 94035. and fastened by the V^in. Viton O-ring vacuum fitting of a Cajon Ultra Torr reducing union (G) (Cajon Company, 32550 Old South Miles Road, Cleveland, Ohio 44139).…”

Solid-state isotope dilution in spark source mass spectrometry

“…The photoplates were read using a Jarrell-Ash Model 23-100 scanning microdensitometer interfaced with a PDP 11/20 minicomputer. The system has been recently described (9). Peak areas were used in all calculations to eliminate errors due to line-width fluctuations.…”

Improvement in the analysis of ashes from coal by spark source mass spectrography

“…These formulae are especially useful for computer application (38). The Hull equation (225) (198,(226)(227)(228)(229)(230) and an improvement over other methods of calibration (231,232). The Kinoshita equation (233) is derived theoretically.…”