Compensation for attenuation, scatter, and detector response in SPECT reconstruction via iterative FBP methods

The flame ionisation detector response to C6-C11 aliphatic hydrocarbon solutions in carbon disulphide in the concentration range between 1.3-9.5 mg ml-1 retained lineary despite the excess of solvent entering the detector simultaneously with the analyte. Pure carbon disulphide exhibited a small positive detector response which did not interfere in calibration procedure and which, under certain GC conditions, inverted to negative values. This response was not proportional to the injected volume and was strongly influenced by the column temperature and/or bleed. On the basis of these findings, a method compatible with the widely used charcoal tube carbon disulphide desorption procedure was developed and evaluated. It consists of static desorption of the sum of aliphatic alkanes and cycloalkanes from the activated charcoal after which an internal standard is added to the supernatant eluate. The resulting carbon disulphide solution is analysed on a highly polar stationary phase 1,2,3-tris(2-cyanoethoxy)propane where the solvent and the analyte coelute in a single peak, the height of which is practically proportional to the sum of alkanes and cycloalkanes present. This also makes determinations of other substances present in the sample more simple. The field test of the proposed method yielded values comparable in precision and accuracy with a control infrared spectrophotometric method.

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Screening and quantification of hypnotic sedatives in serum by capillary gas chromatography with a nitrogen-phosphorus detector, and confirmation by capillary gas chromatography-mass spectrometry.

Clinical Chemistry ◽

10.1093/clinchem/32.2.325 ◽

1986 ◽

Vol 32 (2) ◽

pp. 325-328 ◽

Cited By ~ 18

Author(s):

V A Soo ◽

R J Bergert ◽

D G Deutsch

Keyword(s):

Mass Spectrometry ◽

Gas Chromatography ◽

Capillary Gas Chromatography ◽

Gas Chromatography Mass Spectrometry ◽

Detector Response ◽

Capillary Gc ◽

Chromatography Mass Spectrometry ◽

Nitrogen Phosphorus Detector ◽

Sedative Drugs ◽

Nitrogen Phosphorus

Abstract We describe a quantitative screen for hypnotic-sedative drugs in which we use capillary gas chromatography with a nitrogen-phosphorus detector (GC/NPD) as the primary method and capillary gas chromatography-mass spectrometry (GC-MS) for confirmation. GC retention times of the acid-extracted underivatized drugs were stable (CVs less than 1%), and the detector response varied linearly over a 20-fold concentration range with a mean correlation coefficient for 11 drugs of 0.989. The limits of detection were satisfactory (0.5 mg/L in a 0.5-mL serum sample and 1-microL injection volume), as were precision (average CV 5.2% within day, 6.4% between day). The complementary use of capillary GC-MS not only unambiguously confirms presumptive peaks identified by GC, but also prevents reports of false positives and identifies compounds not included in the quantitative GC screen that may be listed in the GC-MS library.

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LR-115 detector response to 222Rn, 220Rn and their progenies, exposed to hemispherical surfaces in free air, and design of a system to calculate their concentrations

Radiation Measurements ◽

10.1016/j.radmeas.2008.03.047 ◽

2008 ◽

Vol 43 ◽

pp. S435-S439 ◽

Cited By ~ 3

Author(s):

D. Palacios ◽

F. Palacios ◽

L. Sajó-Bohus ◽

H. Barros ◽

E.D. Greaves

Keyword(s):

Detector Response ◽

Free Air

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Detector response and calibration of the cosmic-ray detector of the Sileye-3/Alteino experiment

Advances in Space Research ◽

10.1016/j.asr.2005.03.136 ◽

2006 ◽

Vol 37 (9) ◽

pp. 1691-1696 ◽

Cited By ~ 16

Author(s):

M. Casolino ◽

V. Bidoli ◽

M. Minori ◽

L. Narici ◽

M.P. De Pascale ◽

...

Keyword(s):

Cosmic Ray ◽

Detector Response

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