| 1. |
- Grahn, T., et al.
(författare)
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Collectivity and configuration mixing in Pb186,188 and Po194
- 2006
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Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 97:6
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Tidskriftsartikel (refereegranskat)abstract
- Lifetimes of prolate intruder states in Pb186 and oblate intruder states in Po194 have been determined by employing, for the first time, the recoil-decay tagging technique in recoil distance Doppler-shift lifetime measurements. In addition, lifetime measurements of prolate states in Pb188 up to the 8+ state were carried out using the recoil-gating method. The B(E2) values have been deduced from which deformation parameters |β2|=0.29(5) and |β2|=0.17(3) for the prolate and the oblate bands, respectively, have been extracted. The results also shed new light on the mixing between different shapes.
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| 2. |
- Joss, D. T., et al.
(författare)
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Yrast states and band crossings in the neutron-deficient platinum isotopes Pt169-173
- 2006
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Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 74:1
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Tidskriftsartikel (refereegranskat)abstract
- The yrast states in the light platinum isotopes Pt169-173 have been investigated in a recoil-decay tagging experiment using the JUROGAM gamma-ray spectrometer in conjunction with the RITU gas-filled recoil separator and the GREAT tagging spectrometer. Gamma-ray transitions have been established for the first time in the odd-N isotopes, Pt-169 and Pt-173, and the yrast sequences in Pt-170 and Pt-172 have been extended. We discuss the possibility that the weakly deformed yrast structures of Pt-170, Pt-172, and Pt-173 are crossed by a deformed intruder configuration at spin similar to 8h.
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| 3. |
- Joss, D. T., et al.
(författare)
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Yrast structures in the light Pt isotopes Pt169-173
- 2005
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Ingår i: Journal of Physics G. - : IOP Publishing. - 0954-3899 .- 1361-6471. ; 31:10, s. S1715-S1718
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Tidskriftsartikel (refereegranskat)abstract
- The exploitation of the recoil-decay tagging (RDT) technique has reinvigorated experimental investigations of the shape coexistence phenomenon in heavy neutron-deficient nuclei. In a recent experiment using the JUROGAM and GREAT spectrometers in conjunction with the RITU gas-filled separator, excited states have been investigated in the light platinum isotopes. In addition to extending the yrast sequences in Pt-170 and Pt-172, the first observation of excited states in the odd-N isotopes, Pt-169 and Pt-173, is reported. The bands are discussed in terms of trends in level excitation energies as a function of neutron number.
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| 4. |
- Lagergren, Karin, et al.
(författare)
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High-spin states in the proton-unbound nucleus Re-161
- 2006
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Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 74:2, s. 024316-
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Tidskriftsartikel (refereegranskat)abstract
- Excited states in Re-161 were populated using the Cd-106(Ni-58, p2n) reaction at a beam energy of 270 MeV, resulting in the first observation of gamma rays emitted from this nucleus. The reaction products were separated from scattered beam and fission fragments by the gas-filled recoil separator RITU, and were implanted in the double-sided silicon strip detectors of the GREAT spectrometer. Prompt gamma rays were detected by the JUROGAM Ge detector array and were assigned to Re-161 based on alpha- and proton-decay tagging of the implanted reaction products. The near-yrast high-spin level structure, which was delineated to spins around 39/2, is discussed in the context of the total Routhian surface formalism. The level scheme is interpreted in terms of the alignment of h(9/2)/f(7/2) neutrons at lower spins, followed by excitations involving the pi h(11/2) subshell at higher spins.
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| 5. |
- Medina-Gomez, Gema, et al.
(författare)
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The link between nutritional status and insulin sensitivity is dependent on the adipocyte-specific peroxisome proliferator-activated receptor-gamma2 isoform
- 2005
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Ingår i: Diabetes. - : American Diabetes Association. - 0012-1797 .- 1939-327X. ; 54:6, s. 1706-1716
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Tidskriftsartikel (refereegranskat)abstract
- The nuclear receptor peroxisome proliferator-activated receptor-gamma (PPARgamma) is critically required for adipogenesis. PPARgamma exists as two isoforms, gamma1 and gamma2. PPARgamma2 is the more potent adipogenic isoform in vitro and is normally restricted to adipose tissues, where it is regulated more by nutritional state than PPARgamma1. To elucidate the relevance of the PPARgamma2 in vivo, we generated a mouse model in which the PPARgamma2 isoform was specifically disrupted. Despite similar weight, body composition, food intake, energy expenditure, and adipose tissue morphology, male mice lacking the gamma2 isoform were more insulin resistant than wild-type animals when fed a regular diet. These results indicate that insulin resistance associated with ablation of PPARgamma2 is not the result of lipodystrophy and suggests a specific role for PPARgamma2 in maintaining insulin sensitivity independently of its effects on adipogenesis. Furthermore, PPARgamma2 knockout mice fed a high-fat diet did not become more insulin resistant than those on a normal diet, despite a marked increase in their mean adipocyte cell size. These findings suggest that PPARgamma2 is required for the maintenance of normal insulin sensitivity in mice but also raises the intriguing notion that PPARgamma2 may be necessary for the adverse effects of a high-fat diet on carbohydrate metabolism.
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| 6. |
- Nevalainen, H., et al.
(författare)
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Firing of coal and biomass and their mixtures in 50 kW and 12 MW circulating fluidized beds - Phenomenon study and comparison of scales
- 2007
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Ingår i: Fuel. - : Elsevier BV. - 0016-2361. ; 86:14, s. 2043-2051
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Tidskriftsartikel (refereegranskat)abstract
- The combustion dynamics of coal, wood chips and their mixture is investigated. Load change capability and the effect of the individual control variables, for example the mixture ratio of different fuels, on pilot-scale CFB boiler dynamics were also studied. Disturbances in fuel feeding cause fluctuations in the flue gas concentrations. Changes in the heating value are possible due to varying moisture content of the fuel. Both these disturbances affect the instantaneous firing rate in a boiler. Also the characteristics of the fuels have to be taken into consideration when designing boiler control systems. When co-firing two fuels with clearly distinct combustion characteristics, direct assumptions based on each fuel's characteristies cannot be made about combustion behaviour of their mixture. Combustion experiments with coal and wood chips and their co-firing were carried out in a pilot-scale CFB reactor (VTT) and a large-scale CFB boiler (Chalmers). A comparison of the combustion in the two different size reactors, provides information about scaling. The combustion responses due to changes in the fuel feeding of the two circulating fluidized beds are analyzed by a dynamic model. (c) 2007 Elsevier Ltd. All rights reserved.
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| 7. |
- Wiseman, D. R., et al.
(författare)
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In-beam gamma-ray spectroscopy of Po-190,Po-197
- 2007
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Ingår i: European Physical Journal A. - : Springer Science and Business Media LLC. - 1434-6001 .- 1434-601X. ; 34:3, s. 275-281
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Tidskriftsartikel (refereegranskat)abstract
- gamma-ray transitions in the neutron-deficient nuclei Po-190,Po-197 have been identified using the JUROGAM Ge detector array coupled to the RITU gas-filled separator and the GREAT spectrometer. The yrast band of Po-190 has been firmly established through gamma-gamma coincidences and extended up to a spin and parity of 14(+). It displays similar behaviour to its isotones Hg-186 and Pb-188 above the 4(+) level, thus confirming its prolate nature. In Po-197 the band built upon the 13/2(+) isomer has been extended up to a spin and parity of 33/2(+), while the non-yrast band has been observed for the first time. The behaviour of Po-197 is found to be similar to that of the nearby even-mass isotopes, which is consistent with the model in which the i(13/2) neutron is weakly coupled to the states in the even-even core.
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| 8. |
- Wiseman, D. R., et al.
(författare)
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Probe of triple shape coexistence in neutron deficient polonium nuclei
- 2006
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Ingår i: AIP Conf. Proc.. - : AIP. - 0735403236 - 9780735403239 ; , s. 560-562
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Konferensbidrag (refereegranskat)abstract
- γ-ray transitions in the neutron deficient 190,197Po nuclei have been identified. The yrast band of 190Po has been extended up to a spin and parity of 14+ and is found to display similar systematic behaviour to isotones 186Hg and 188Pb above the 4+ level, thus confirming its prolate nature. In 197Po the band built upon the 13/2+ isomer has been extended up to a spin and parity of 33/2+, while the non-yrast side-band has been observed for the first time. The behaviour of 197Po is found to be similar to that of the nearby even-mass isotopes, which is consistent with the model in which the i13/2 neutron is weakly coupled to the states in the even-even core.
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