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Determination of 36Cl in biological shield concrete using pyrohydrolysis and liquid scintillation counting

“…In the determination of 36 Cl in soil, Cl was recovered as an AgCl precipitate after alkali fusion of the sample. 5 It took more than 1 d to prepare the sample for LSC. The extraction techniques reported are tedious and time consuming and they do not appear to be suitable for routine analysis of concrete samples.…”

Atomic spectrometry update. Atomic mass spectrometry

“…303 Instead of using hazardous CO as the reference standard, CO 2 was used as an alternative with CO 1 fragment ions acting as the running standard. The CO 2 was introduced into the mass spectrometer just before and after the CO peak and the 28 CO, 29 CO and 30 CO species monitored simultaneously and continuously. The SD was 0.2 and 0.4% for d 13 C and d 18 O, respectively, for as little as 300 pmol CO.…”

“…A Si(Li) detector was mounted at 90u to the incident beam in order to minimize Doppler broadening and avoid the Bremsstrahlung background from the electrostatic detector. The PXD technique achieved almost total separation of 36 Cl and 36 S in the determination of 36 Cl in soil samples, even in the presence of high concentrations of S. 29 Although the LOD for 36 Cl : Cl of 1 6 10 211 was sufficient for analysis of soils from a nuclear test site, further developments would be required to measure the level generally found in the environment ( 36 Cl:Cl ~1 6 10 213 ).…”

“…The method was tested using RM TORT-2, BCR 463 and DORM-2. Resano et al 122 investigated the direct determination of trace amounts of Si in polyamides by solid sampling ETV-ICP-MS. Optimized analytical conditions included a vaporization temperature of 2400 uC, the use of 1 mg of Pd as a chemical modifier and the monitoring of 29 Si 1 . Advantages of the technique were considered to be the low LOD of 0.3 mg g 21 , the use of aqueous standard solutions for calibration, low sample consumption (few mg), high sample throughput (20 min per sample) and the minimal risk of sample loss and contamination.…”

“…170 Although the use of a fluorinating gas in the conventional determination of Si isotope ratios can be avoided, long rinsing and sample introduction times, high backgrounds and interferences were significant difficulties. Solving these problems led to measurement of d 29 Si with a precision of 0.01%…”