Scintillator uses

The sensor is a crystal of Nal(TI) that transforms the 7 photon into luminescence whose intensity is proportional to the energy of the photon (assuming that the 7 photon is entirely absorbed by the crystal). The principle is similar to that of liquid scintillators used to measure 14C. If a Ge(Li) crystal is used, it behaves like the support gas in a Geiger-Muller tube. 

There are two ways to operate the stop-flow mode. The by-level mode, which is based upon the defined count zone(s), operates by signaling the instalment to continue running until a radioactive peak above a designated level is detected. The instrument will then stop and count the predefined fraction (in seconds), which is defined in the count zone. A second way to operate the stop-flow mode is the by-fraction mode. The instalment will stop and count every fraction (in seconds) within the predefined count zone, regardless of whether any radioactivity is detected or not. The fraction size in the stop-flow mode and the volume of liquid scintillant used for counting can be automatically calculated by the instalment or the parameters can be defined by the user. 

A thorough calibration of the ((-spectrometer regarding different sample matrices and sizes, the scintillator used, different dissolutions, different colorations of the samples, different amounts of CO2 after combustion and of course different radioactivity concentrations should be ensured. Calibration and control samples can be set up by using internal standard kits (for instance 14C-0 Standard from PerkinElmer Wallac GmbH D-79111 Freiburg). 

Thyroxine and thyroxine glucuronide were separated on a C]8 Ultrabase column (4.6 mm X 250 mm, 10 p.m). Solvent A was a 35 65 (v/v) mixture of methanol and 20 mM potassium phosphate buffer (pH 7.0) containing 1% triethylamine. Solvent B was methanol. A linear gradient from 0 to 100% B was run in 15 minutes. Elution was completed by maintaining 100% B for 5 minutes. Two methods of on-line radiochemical detection was used liquid scintillation using a 2 mL detection cell, and solid scintillation using lithium scintillator glass in an effective cell volume of 400 p-L. The latter method was most convenient. 

The sample container or vial must be transparent at the wavelength of the scintillator used and resistant to the solvent. Preferably it is put between two photomultipliers to obtain higher counting efficiency. Using this arrangement the thermal... 

Scintillators used for y-ray detection from TC43 (141 kev), kev) and Tlgi (75 kev), include NaI Tl and Bi GCgO available in 80 cm single-crystal plates, a form not easily achieved by other scintillator phosphor compositions. 

The basic structure of a phoswich detector is shown in Fig. 6.18. A thin scintillator (scintillator A) is coupled to a larger crystal (scintillator B), which in turn is coupled to the cathode of a single phototube. Two examples of scintillators used are these ... 

Organic Scintillators Used as Fast-Neutron Spectrometers... 

FIGURE 11.2 Inside view of the anticyclotron trap II, with the degraders and target in position. One of the degrader (horizontal, right) is a plastic scintillator used to monitor particle beam intensity. 

Yanagida, T., Fujimoto, Y, Kurosawa, S. et al. 2011a. Ultrafast transparent ceramic scintillators using the Yb charge transfer luminescence in REjOj Host. Applied Physics Express 4 126402. 

Commercial solgel (emulsion) scintillators used were Aquasol II and Biofluor (New England Nuclear), Beckman GP (Beckman Instr.), and PCS (Amersham Corp.). Solvents used were p-xylene (ICN spectral grade) and toluene (Packard "Puresolv") and the scintillators were p-bis-Co-methylstyryl)-benzene (bis-MSB from Eastman Kodak) and 2-(4 -t-butylphenyl)-5-(4"-biphenylyl)-1,3,4-oxadiazole (butyl-PBD from ICN). The chelating agent was di-2-ethylhexyl phosphoric acid (HDEHP) obtained from K K Laboratories and used without further purification. Radionuclide solutions of known radioactivity concentration were supplied by other workers in the NBS Radioactivity Group (Mann, 1979). 

Liquid scintillators, used in the experiment, were of standard commercial quality, such as Aqualuma Plus, Rialuma and Lumagel (Lumac Systems AG, Basel, Switzerland), and Triton - X 100 toluene scintillators prepared according to Patterson and Green (Patterson, 1965). Scintillation vials were from the same company as the liquid scintillators (Milli -6 / Milli-20 glass and polyethelene). 

An ultra-sensitive method was developed for U and Th as well as for determination in liquid scintillators used for neutrino and dark matter experiments. In the RNAA procedure, 250 ml of irradiated cocktail was chemically processed and indicator nuclides of U and Th, namely, Np and Pa were extracted with tributylphosphate (TBP). Using coincidence techniques, a sensitivity for U down to 10 g/g was realized (Goldbrunner et al. 1998). 

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