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641.
Bhattacharyya P Daly PJ Zhang CT Grabowski ZW Saha SK Broda R Fornal B Ahmad I Seweryniak D Wiedenhöver I Carpenter MP Janssens RV Khoo TL Lauritsen T Lister CJ Reiter P Blomqvist J 《Physical review letters》2001,87(6):062502
Prompt and delayed gamma-ray cascades in doubly magic 132Sn and its neighbor 131Sn have been studied at Gammasphere using a 248Cm fission source. Isotopic assignments of unknown gamma rays were based on coincidences with known transitions in A = 112-116 Pd fission partners. The yrast level spectra of both tin nuclei are interpreted using empirical nucleon-nucleon interactions from the 132Sn and 208Pb regions. Results include identification of the (nuf(7/2)h(-1)(11/2))9(+) aligned state in 132Sn and of extensive (nuf(7/2)h(-2)(11/2)), (nuf(7/2)d(-1)(3/2)h(-1)(11/2)) and (nuh(-1)(11/2)x3(-)) multiplets in 131Sn. The previously reported beta(-) decay of an unusual 131In high-spin isomer to levels in 131Sn is also elucidated. 相似文献
642.
H. Grawe M. Górska M. Lipoglavisek R. Schubart A. Ataç A. Axelsson J. Blomqvist J. Cederkäll G. de Angelis M. de Poli C. Fahlander A. Johnson K.H. Maier L.-O. Norlin J. Nyberg D. Foltescu M. Palacz J. Persson M. Rejmund H.A. Roth T. Shizuma Ö. Skeppstedt G. Sletten M. Weiszflog 《Zeitschrift für Physik A Hadrons and Nuclei》1997,358(2):185-190
The present status of experimental approach to 100Sn in the spectroscopy of excited states is landmarked by the Tz=3/2 nuclei between 95Pd and 101In and the Tz=1 nuclei 94Pd and 98Cd. The detection limits with Pre-EUROBALL γ-arrays and ancillary detectors are below the 10?5 level of the total fusion- evaporation residue cross section. A large scale shell model analysis of the existing data reveals the shell structure at 100Sn, which shows a remarkable similarity to 56Ni. Evidence for an increasing proton-neutron interaction in approaching the N=Z line is deduced from high spin isomers and spherical yrast lines. The effective E2 operator for protons and neutrons and implications for a low lying particle-hole (ph) E2 excitation in 100Sn are discussed. 相似文献
643.
644.
Analytical and Bioanalytical Chemistry - 相似文献
645.
Johanna Sepp 《Fresenius' Journal of Analytical Chemistry》1960,172(6):441
Ohne Zusammenfassung 相似文献
646.
647.
M. Lipoglavšek M. Górska J. Nyberg A. Atac A. Axelsson R. A. Bark J. Blomqvist J. Cederkäll B. Cederwall G. de Angelis C. Fahlander H. Grawe A. Johnson S. Leoni A. Likar M. Matiuzzi S. Mitarai L. -O. Norlin M. Palacz J. Persson H. A. Roth R. Schubart D. Seweryniak T. Shizuma Ö. Skeppstedt D. Sohler G. Sletten W. B. Walters M. Weiszflog 《Zeitschrift für Physik A Hadrons and Nuclei》1996,356(1):239-240
Excited states in102Sn have been identified for the first time, in an in-beamγ-ray spectroscopic experiment. Twoγ-ray transitions with energies 1472 and 497 keV following the decay of the seniority 6+ isomer with t1/2=1.0(5)μs were unambiguously assigned to102Sn. Due to the very low cross section of about 2µb for producing102Sn in the reaction50Cr(58Ni,1α2n), a highly selective detector setup utilizing NORDBALL ancillary detectors and a recoil catcher device was used. Highγ-ray detection efficiency was achieved with two EUROBALL Ge cluster detectors. 相似文献
648.
We present optical spectroscopy studies of the conjugated polymer poly(9,9-di-n-octylfluorene-alt-benzothiadiazole) (F8BT) at high pressure. The photoluminescence spectrum of F8BT in a dilute solid-state solution in polystyrene redshifts by 320 meV over 7.4 GPa, while that of a F8BT thin film redshifts 460 meV over a comparable pressure range. We attribute the redshift in solution to intrachain pressure effects, principally conformational planarization. The additional contribution from interchain pi-electron interactions accounts for the larger redshift of thin films. 相似文献
649.
Using a novel, string theory-inspired formalism based on a Hamiltonian constraint, we obtain a conformal mechanical system for the spatially flat four-dimensional Robertson-Walker Universe. Depending on parameter choices, this system describes either a relativistic particle in the Robertson-Walker background or metric fluctuations of the Robertson-Walker geometry. Moreover, we derive a tree-level M theory matrix model in this time-dependent background. Imposing the Hamiltonian constraint forces the spacetime geometry to be fuzzy near the big bang, while the classical Robertson-Walker geometry emerges as the Universe expands. From our approach, we also derive the temperature of the Universe interpolating between the radiation and matter dominated eras. 相似文献
650.
Naffziger MR Ashburn BO Perkins JR Carter RG 《The Journal of organic chemistry》2007,72(26):9857-9865
A rapid Diels-Alder approach to halogenated biaryl templates is described. These biaryl templates are available in two steps from the corresponding aromatic aldehydes. The scope of subsequent Suzuki couplings on the biaryl chlorides is explored. Good tolerance for both electron-donating and electron-withdrawing groups in the coupling process can be achieved. Further functionalization of the biaryl templates is described. Hydrogenation of the nitro moiety with concomitant removal of the benzyl ether yields the o-anilino, o-phenolic polyaryls. Selective reduction of the nitro group can be accomplished. Alternatively, the benzyl ether can be selectively removed under Lewis acidic conditions. The utilization of the Diels-Alder adducts for the synthesis of a series of chlorinated carbazoles via the Cadogan cyclization is also demonstrated. Finally, application of this technology to the total synthesis of siamenol, an anti-HIV agent, is reported. 相似文献