[en] The dynamic structure S(Q,ω) has been obtained on liquid Bismuth by means of neutron inelastic scattering technique. The measurements were performed at two temperatures T = 559 K, 675 K using a time of flight spectrometer. Two recent theoretical models on collective motions in simple liquids were used to compare the experimental results. A Lennard-Jones pair interaction potential is chosen to calculate the second and the fourth order energy momenta. (author)
Journal
Revue Roumaine de Physique; ISSN 0035-4090; 
; v. 23(4); p. 379-391
; v. 23(4); p. 379-391
[en] A new hybrid time-of-flight thermal neutron spectrometer has been installed at the 14 Mw TRIGA reactor in Pitesti. This spectrometer is intended to be used for the study of inelastic neutron scattering and time-of-flight diffraction. Two pairs of pyrolitic graphite or copper crystals allow a continuous wavelength variation within the limits (1;6) A. The pulsing of the neutrons as well as the elimination of the high order reflection is performed by a chopper with curved slits. The detection system consists of the He3 counters while the data handling is fulfiled by a computer PDP-11/04
Source
Anon; p. 875-879; ISBN 92-64-01870-0; ; 1978; p. 875-879; OECD; Paris, France; International conference on neutron physics and nuclear data for reactors and other applied purposes; Harwell, UK; 25 - 29 Sep 1978
; 1978; p. 875-879; OECD; Paris, France; International conference on neutron physics and nuclear data for reactors and other applied purposes; Harwell, UK; 25 - 29 Sep 1978
[en] The 'low-level methods' in gamma spectrometry are inefficient when many gamma rays are present, due to Compton continuum. In such cases an anti-Compton guard detector is necessary. In the Radionuclide Metrology Laboratory (RML) a NaI (Tl) guard detector was added to the usual Ge(Li) detector. It is provided by BICRON (USA) and has 230 mm in diameter and 230 mm long, with a hole for the Ge(Li) detector. Eight photomultipliers collect the light. Pulses from the guard detector are blocking the gate of the MCA. Spectra for 137 Cs, 60 Co and 152 Eu were studied. With Compton rejection, the Compton plateau practically disappears from the spectra, as well as the broad peak due to the backscattering. A rejection factor of 4 was obtained for 137 Cs. A complication arises from the coincidences between different gamma rays. The described method is useful when a high energy line is preponderant, as in biological and soil samples containing 40 K. The RML does routine work on such samples. (authors)
Source
Carstea, Stefan; Dragulici, Felicia; Enescu, Sanda-Elena; Oancea, Margareta; Preda, Mihaela; Prodan, Lucia; Raduta, Adriana; Sandu, Doina; Schiaua, Claudiu (Horia Hulubei National Institute for Physics and Nuclear Engineering, PO Box MG-6, RO-76900 -Bucharest-Magurele (Romania)); Horia Hulubei National Institute for Physics and Nuclear Engineering, IFIN-HH, PO Box MG-6, RO-76900 Bucharest-Magurele (Romania); 175 p; ISSN 1454-2714; ; 2000; p. 119; Available from author(s) or Office of Documentation, Publication and Printing, Horia Hulubei National Institute for Physics and Nuclear Engineering, PO Box MG-6, RO-76900 -Bucharest-Magurele (RO); Available from Office of Documentation, Publication and Printing, Horia Hulubei National Institute for Physics and Nuclear Engineering, PO Box MG-6, RO-76900 Bucharest-Magurele (RO); Short communication
; 2000; p. 119; Available from author(s) or Office of Documentation, Publication and Printing, Horia Hulubei National Institute for Physics and Nuclear Engineering, PO Box MG-6, RO-76900 -Bucharest-Magurele (RO); Available from Office of Documentation, Publication and Printing, Horia Hulubei National Institute for Physics and Nuclear Engineering, PO Box MG-6, RO-76900 Bucharest-Magurele (RO); Short communication
[en] The named diffractometer is described. The results of a test measurement on an Al2O3 sample concerning the resolution are presented. (HSI)
Source
Mainz Univ. (Germany). Inst. fuer Kernchemie; 233 p; ISBN 3-00-001449-7; ; 1996; 5 p; 14. European TRIGA conference; Mainz (Germany); 22-25 Sep 1996; Available from TIB Hannover
; 1996; 5 p; 14. European TRIGA conference; Mainz (Germany); 22-25 Sep 1996; Available from TIB Hannover