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761.
Nishimura S Li Z Watanabe H Yoshinaga K Sumikama T Tachibana T Yamaguchi K Kurata-Nishimura M Lorusso G Miyashita Y Odahara A Baba H Berryman JS Blasi N Bracco A Camera F Chiba J Doornenbal P Go S Hashimoto T Hayakawa S Hinke C Ideguchi E Isobe T Ito Y Jenkins DG Kawada Y Kobayashi N Kondo Y Krücken R Kubono S Nakano T Ong HJ Ota S Podolyák Z Sakurai H Scheit H Steiger K Steppenbeck D Sugimoto K Takano S Takashima A Tajiri K Teranishi T Wakabayashi Y Walker PM Wieland O Yamaguchi H 《Physical review letters》2011,106(5):052502
The β-decay half-lives of 38 neutron-rich isotopes from (36)Kr to (43)Tc have been measured; the half-lives of (100)Kr, (103-105)Sr, (106-108)Y, (108-110)Zr, (111,112)Nb, (112-115)Mo, and (116,117)Tc are reported here. The results when compared with previous standard models indicate an overestimation in the predicted half-lives by a factor of 2 or more in the A≈110 region. A revised model based on the second generation gross theory of β decay better predicts the measured half-lives and suggests a more rapid flow of the rapid neutron-capture process (r-matter flow) through this region than previously predicted. 相似文献
762.
Nara Singh BS Liu Z Wadsworth R Grawe H Brock TS Boutachkov P Braun N Blazhev A Górska M Pietri S Rudolph D Domingo-Pardo C Steer SJ Ataç A Bettermann L Cáceres L Eppinger K Engert T Faestermann T Farinon F Finke F Geibel K Gerl J Gernhäuser R Goel N Gottardo A Grębosz J Hinke C Hoischen R Ilie G Iwasaki H Jolie J Kaşkaş A Kojouharov I Krücken R Kurz N Merchán E Nociforo C Nyberg J Pfützner M Prochazka A Podolyák Z Regan PH Reiter P Rinta-Antila S Scholl C Schaffner H Söderström PA Warr N 《Physical review letters》2011,107(17):172502
A β-decaying high-spin isomer in (96)Cd, with a half-life T(1/2)=0.29(-0.10)(+0.11) s, has been established in a stopped beam rare isotope spectroscopic investigations at GSI (RISING) experiment. The nuclei were produced using the fragmentation of a primary beam of (124)Xe on a (9)Be target. From the half-life and the observed γ decays in the daughter nucleus, (96)Ag, we conclude that the β-decaying state is the long predicted 16(+) "spin-gap" isomer. Shell-model calculations, using the Gross-Frenkel interaction and the πν(p(1/2),g(9/2)) model space, show that the isoscalar component of the neutron-proton interaction is essential to explain the origin of the isomer. Core excitations across the N=Z=50 gaps and the Gamow-Teller strength, B(GT) distributions have been studied via large-scale shell-model calculations using the πν(g,d,s) model space to compare with the experimental B(GT) value obtained from the half-life of the isomer. 相似文献
763.
Makk P Visontai D Oroszlány L Manrique DZ Csonka S Cserti J Lambert C Halbritter A 《Physical review letters》2011,107(27):276801
We demonstrate a self-contained methodology for predicting conductance histograms of atomic and molecular junctions. Fast classical molecular-dynamics simulations are combined with accurate density functional theory calculations predicting both quantum transport properties and molecular-dynamics force field parameters. The methodology is confronted with experiments on atomic-sized indium nanojunctions. Beside conductance histograms the distribution of individual channel transmission eigenvalues is also determined by fitting the superconducting subgap features in the I-V curves. The remarkable agreement in the evolution of the channel transmissions demonstrates that the simulated ruptures are able to reproduce a realistic statistical ensemble of contact configurations, whereas simulations on selected ideal geometries show strong deviations from the experimental observations. 相似文献
764.
S.J. Dilworth E. Odell Th. Schlumprecht A. Zsák 《Journal of Approximation Theory》2011,163(9):1049-1075
We continue the study of -greedy bases initiated by Albiac and Wojtaszczyk (2006) [1]. We answer several open problems that they raised concerning symmetry properties of -greedy bases and the improving of the greedy constant by renorming. We show that -greedy bases need not be symmetric or subsymmetric. We also prove that one cannot in general make a greedy basis -greedy as demonstrated for the Haar basis of the dyadic Hardy space and for the unit vector basis of Tsirelson space. On the other hand, we give a renorming of () that makes the Haar basis -unconditional and -democratic. Other results in this paper clarify the relationship between various basis constants that arise in the context of greedy bases. 相似文献
765.
A. Eremin L. Naji A. Nemes R. Stannarius M. Schulz K. Fodor‐Csorba 《Liquid crystals》2013,40(7):789-794
A wide variety of morphologies, such as screw‐like filaments, ribbons, etc., have been observed in polarizing microscopy studies of the B7 phase in a melt or with free surface. In this paper, we present the results of AFM and scanning electron microscopy measurements of structures formed by a columnar‐type B7 phase. These measurements are aimed at elucidating the three‐dimensional structure of the observed patterns. 相似文献
766.
Abstract The living polymerization of styrene was achieved with the 2,4,4-trimethyl-2-pentyl chloride/TiCl4/MeCl:methylcyclohexane 40:60 v:v/?80°C polymerization system in the presence of di-tert-butylpyridine in concentrations comparable to the concentration of protic impurities. It was determined that the living nature of the polymerization is not due to carbocation stabilization. The polymerization is second order in TiCl4. Side reactions, namely polymerization by direct initiation and intermolecular alkylation, are operational, and a careful selection of experimental conditions is necessary to minimize their effect and obtain apparently living behavior. Polymerization by direct initiation can be minimized by increasing the initiator concentration, and intermolecular alkylation can be reduced by quenching the polymerization system when the conversion reaches close to 100%. 相似文献
767.
The characteristic fragmentation pattern of six reducing and two non reducing type disaccharides-(neohesperidose, acuminose, sambubiose, rutinose, vicianose, primverose, and two arabinosyl-inositols) has been described. These saccharides have not been previously identified by on-line chromatographic techniques. Unambiguous specific characteristics of the TMS (oxime)s such as mass distribution, syn/anti oximes ratios and elution order proved to be associated with their reducing or non reducing character, with their aldosyl property and with the position of their O-glycosidic linkages. The practical utility of the mass fragmentation study of these rare disaccharides was demonstrated, at the first time, by the simultaneous, on-line identification and quantification of the acuminose, vicianose, primverose and arabinosyl-inositol contents of tea leaves, from green and black tea blends of Indian and Chinese origin. 相似文献
768.
Lajos Fodor Péter Csomós Tamás HolczbauerAlajos Kálmán Antal CsámpaiPál Sohár 《Tetrahedron letters》2011,52(2):224-227
The ring-enlargement reactions of monochloro-β-lactam-fused 2-aryl-1,3-benzothiazines revealed that the reactions of ortho-nitro aryl-substituted derivatives with sodium methoxide in methanol provided two products, depending on the amount of the base. With 2 equiv of reagent, the expected 1,4-benzothiazepines were obtained. Somewhat surprisingly, treatment with a large excess of sodium methoxide led to the formation of indolo-1,4-benzothiazepines via a novel rearrangement. The structures of the new ring systems were determined by means of X-ray crystallography and NMR spectroscopy. 相似文献
769.
M. Kmiecik A. Maj J. Gerl G. Neyens L. Atanasova D. L. Balabanski F. Becker P. Bednarczyk G. Benzoni N. Blasi A. Bracco S. Brambilla L. Caceres F. Camera M. Ciema?a F. C. L. Crespi S. K. Chamoli S. Chmel J. M. Daugas P. Detistov P. Doornenbal G. Georgiev K. Gladnishki M. Górska H. Grawe J. Gr?bosz M. Hass R. Hoischen G. Ilie M. Ionescu-Bujor J. Jolie I. Kojuharov A. Krasznahorkay R. Kulessa M. Lach S. Lakshmi S. Leoni G. Lo Bianco R. Lozeva K. H. Maier S. Mallion K. Mazurek W. M?czyński B. Million D. Montanari S. Myalski C. Petrache M. Pfützner S. Pietri Zs. Podolyák W. Prokopowicz D. Rudolph N. Saito T. R. Saito A. Saltarelli G. S. Simpson J. Styczeń N. Vermeulen E. Werner-Malento O. Wieland H. J. Wollersheim M. Zi?bliński 《The European Physical Journal A - Hadrons and Nuclei》2010,43(2):153-158
Reactions of a 16.8 MeV 6He beam with a 9Be target have been investigated using highly segmented detector setup covering a large solid angle. Data on elastic and quasi-free scattering, as well as two-neutron transfer, are reported. The results for elastic scattering are fairly well reproduced by a CDCC calculation, in agreement with the interpretation of a breakup effect already observed for the scattering of 6He on other light targets. Exotic quasi-free scattering of 6He on $ \alpha$ -cluster in 9Be is clearly observed. Inclusive and coincident events were used to extract information on the two-neutron transfer reaction 9Be(6He, $ \alpha$ )11Be . Sequential decay of the 11Be state at the excitation energy $\ensuremath E_x = 10.6$ MeV through different channels is discussed. 相似文献
770.
Sandra Demel Christian Slugovc Franz Stelzer Katalin Fodor‐Csorba Giancarlo Galli 《Macromolecular rapid communications》2003,24(10):636-641
Perfectly alternating copolymers can be synthesised by reacting diacrylates with terminal dienes using alternating diene metathesis polycondensation (ALTMET). This novel method is very versatile and allows preparation of diverse structures of polymers, including main‐chain liquid crystalline polymers.