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1.
N. Stradling G. Etherington A. Hodgson M.R. Bailey S. Hodgson P. Pellow A.L. Shutt A. Birchall E. Rance D. Newton K. Fifield 《Journal of Radioanalytical and Nuclear Chemistry》2002,252(2):315-325
Due to the paucity of human data after inhalation of different chemical forms of radionuclides, the implications for human exposure are often based on animal studies. This paper describes biokinetic studies of plutonium nitrate and gadolinium oxide in human volunteers and rats. The results, together with information from other studies with radionuclides, suggests that animal studies can be used with advantage for assessing the biokinetic behavior in humans, and for providing guidance on the assessment of intake and optimal monitoring regimens. 相似文献
2.
Accelerator mass spectrometry (AMS) was used to measure 237Np in environmental water samples extracted from Irish Sea sediments. The samples were of limited volume (approximately 700 ml) and of low activity (0.06-0.79 mBq l-1; 2.30-30.3 pg l-1). AMS proved to have the required sensitivity for measuring these samples, and was in principle capable of measuring much smaller amounts, as low as 0.4 microBq (3.9 x 10(7) atoms). However, the background level in the procedural blanks showed that there was a systematic low level 237Np contamination of each sample, arising from the 239Np yield monitor used in the separations procedure, which effectively increased the detection limit of these analyses. 相似文献
3.
4.
The 13C(6Li, t)16O reaction has been studied at 34 MeV. Selective population of narrow states is observed up to 21 MeV excitation in 16O. This reaction populates strongly both unnatural-and natural-parity states that have little or no 12C + α0 width. The measured angular distributions are compared with Hauser-Feshbach and finite-range DWBA calculations. Reasonable agreement with the DWBA calculations is found for most of the states strongly populated. The widths of the narrow states populated in the 16–20 MeV excitation region are presented. Comparison of the present data with that from medium-energy inelastic scattering and other multiparticle transfer reactions is made. 相似文献
5.
L.K. Fifield M.J. Hurst E.F. Garman T.J.M. Symons F. Watt K.W. Allen 《Nuclear Physics A》1980,334(1):109-126
Nine levels in the range 8.7 to 12.5 MeV in 20Ne have been investigated with the 16O(α, γ)20Ne and 16O(α, α')16O1(6.13 MeV) reactions using a differentially pumped windowless gas target. Three of the levels have not been observed previously in these reactions, and new information has been obtained for most of the others. In particular, the 11.27 MeV 1? level is shown to have T = 1, a result of relevance to a proposed parity violation experiment, and the analogue of the 1.97 MeV (3?T = 1) level in 20F is shown to lie at 12.25 MeV in 20Ne rather than at 12.39 MeV as proposed previously. In addition, the 12.25 MeV level has a width Γ < 1 keV, in contrast to the value Γ ~ 5 keV reported in other work. The electromagnetic transition rates for positive parity T = 1 states in 20Ne are compared with shell-model calculations. 相似文献
6.
M.A.C. Hotchkis L.K. Fifield J.R. Leigh T.R. Ophel G.D. Putt D.C. Weisser 《Nuclear Physics A》1983,398(1):130-140
The neutron-rich nuclei 15B and 19N have been produced in reactions between 18O and 48Ca. Mass excesses of 28.968 ± 0.025 MeV and 15.872 ± 0.020 MeV respectively were deduced from the reaction Q-values. These results are compared with previous measurements and theoretical predictions. Updated predictions using two different mass formulae are presented. 相似文献
7.
Unambiguous spin and parity assignment have been made from angular correlation measurements to states in 20Ne at 15.18 MeV (6+) and 17.40 MeV (9?). Our results are in disagreement with an earlier 9? assignment to the 15.18 MeV state. The 17.40 MeV state is assigned to the K = 2? rotational band based on the 2? state at 4.97 meV. 相似文献
8.
P. P. Povinec M. K. Pham J. A. Sanchez-Cabeza G. Barci-Funel R. Bojanowski T. Boshkova W. C. Burnett F. Carvalho B. Chapeyron I. L. Cunha H. Dahlgaard N. Galabov L. K. Fifield J. Gastaud J. -J. Geering I. F. Gomez N. Green T. Hamilton F. L. Ibanez M. Ibn Majah M. John G. Kanisch T. C. Kenna M. Kloster M. Korun L. Liong Wee Kwong J. La Rosa S. -H. Lee I. Levy-Palomo M. Malatova Y. Maruo P. Mitchell I. V. Murciano R. Nelson A. Nouredine J. -S. Oh B. Oregioni G. Le Petit H. B. L. Pettersson A. Reineking P. A. Smedley A. Suckow T. D. B. van der Struijs P. I. Voors K. Yoshimizu E. Wyse 《Journal of Radioanalytical and Nuclear Chemistry》2007,273(2):383-393
A reference material designed for the determination of anthropogenic and natural radionuclides in sediment, IAEA-384 (Fangataufa
Lagoon sediment), is described and the results of certification are presented. The material has been certified for 8 radionuclides
(40K, 60Co, 155Eu, 230Th, 238U, 238Pu, 239+240Pu and 241Am). Information values are given for 12 radionuclides (90Sr, 137Cs, 210Pb (210Po), 226Ra, 228Ra, 232Th, 234U, 235U, 239Pu, 240Pu and 241Pu). Less reported radionuclides include 228Th, 236U, 239Np and 242Pu. The reference material may be used for quality management of radioanalytical laboratories engaged in the analysis of radionuclides
in the environment, as well as for the development and validation of analytical methods and for training purposes. The material
is available from IAEA in 100 g units.
Retired from IAEA in 2003. 相似文献
9.
L.K. Fifield J.L. Durell M.A.C. Hotchkis J.R. Leigh T.R. Ophel D.C. Weisser 《Nuclear Physics A》1982,385(3):505-515
The mass of 18C has been measured using the double-charge-exchange reaction 48Ca(18O, 18C)48Ti at an 18O energy of 112 MeV. The 18C ions were detected at the focal plane of a magnetic spectrometer. The mass excess of 18C was found to be 24.923 ± 0.030 MeV, and the first excited state was observed at an excitation energy of 1.62 ± 0.02 MeV. At the same time, an independent measurement of the mass excess of 17C was obtained from the 48Ca(18O, 17C)49Ti reaction, and the value 21.039 ± 0.020 MeV is in excellent agreement with an earlier measurement. The first excited state of 17C is at 295 ± 10 keV. 相似文献
10.
M. Chartier W. Mittig G. Auger B. Blank J. M. Casandjian M. Chabert J. Fermщ L. K. Fifield A. Gillibert A. S. Lalleman A. Lépine-Szily M. Lewitowicz M. Mac Cormick M. H. Moscatello F. de Oliveira N. A. Orr G. Politi F. Sarazin H. Savajols C. Spitaels P. Van Isacker A. C. C. Villari M. Wiescher 《Hyperfine Interactions》2001,132(1-4):273-279
The mass-measurement programme at GANIL aims to measure the masses of heavy nuclei close to the N=Z line which is the ideal region to study neutron-proton pairing. An original direct time-of-flight mass-measurement method
was developed at GANIL which uses the CSS2 cyclotron as a high-resolution spectrometer. The masses of ions of A=68,76,80 and 100 have been measured with a precision of a few 10−6. Mass measurements will be performed with the new CIME cyclotron of SPIRAL using a similar method based on the measurement
of the phase of the accelerated ions for different radio-frequencies. A recently approved experiment will help develop this
new technique and aims to measure the mass of 31Ar radioactive nuclei with a precision of 10−6.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献