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441.
Darby IG Grzywacz RK Batchelder JC Bingham CR Cartegni L Gross CJ Hjorth-Jensen M Joss DT Liddick SN Nazarewicz W Padgett S Page RD Papenbrock T Rajabali MM Rotureau J Rykaczewski KP 《Physical review letters》2010,105(16):162502
By studying the (109)Xe→(105)Te→(101)Sn superallowed α-decay chain, we observe low-lying states in (101)Sn, the one-neutron system outside doubly magic (100)Sn. We find that the spins of the ground state (J=7/2) and first excited state (J=5/2) in (101)Sn are reversed with respect to the traditional level ordering postulated for (103)Sn and the heavier tin isotopes. Through simple arguments and state-of-the-art shell-model calculations we explain this unexpected switch in terms of a transition from the single-particle regime to the collective mode in which orbital-dependent pairing correlations dominate. 相似文献
442.
Hildebrand WK Cobus LA Page JH 《The Journal of the Acoustical Society of America》2010,127(5):2819-2824
A statistical method for measuring the modal density of elastic waves through direct mode counting in strongly scattering disordered systems is presented. To illustrate this approach, the results of ultrasonic experiments in a highly porous sintered glass bead network are reported. This method is shown to yield a reliable and robust measurement of the density of states, enabling mode-counting techniques to be applied to increasingly complex systems, where modal overlap and sensitivity to experimental conditions have previously hampered definitive results. 相似文献
443.
Stuart M. MacDonald John D. Watkins Stephen D. Bull Iwan R. Davies Yunfeng Gu Kamran Yunus Adrian C. Fisher Philip C. Bulman Page Yohan Chan Claire Elliott Frank Marken 《Journal of Physical Organic Chemistry》2009,22(1):52-58
A microfluidic double channel device is employed to study reactions at flowing liquid–liquid junctions in contact with a boron‐doped diamond (BDD) working electrode. The rectangular flow cell is calibrated for both single‐phase liquid flow and biphasic liquid–liquid flow for the case of (i) the immiscible N‐octyl‐2‐pyrrolidone (NOP)–aqueous electrolyte system and (ii) the immiscible acetonitrile–aqueous electrolyte system. The influence of flow speed and liquid viscosity on the position of the phase boundary and mass transport‐controlled limiting currents are examined. In contrast to the NOP–aqueous electrolyte case, the acetonitrile–aqueous electrolyte system is shown to behave close to ideal without ‘undercutting’ of the organic phase under the aqueous phase. The limiting current for three‐phase boundary reactions is only weakly dependent on flow rate but directly proportional to the concentration and the diffusion coefficient in the organic phase. Acetonitrile as a commonly employed synthetic solvent is shown here to allow effective three‐phase boundary processes to occur due to a lower viscosity enabling faster diffusion. N‐butylferrocene is shown to be oxidised at the acetonitrile–aqueous electrolyte interface about 12 times faster when compared with the same process at the NOP–aqueous electrolyte interface. Conditions suitable for clean two‐phase electrosynthetic processes without intentionally added supporting electrolyte in the organic phase are proposed. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
444.
T. Grahn A. Dewald P. T. Greenlees U. Jakobsson J. Jolie P. Jones R. Julin S. Juutinen S. Ketelhut T. Kr?ll R. Krücken M. Leino P. Maierbeck B. Melon M. Nyman R. D. Page P. Peura Th. Pissulla P. Rahkila J. Sarén C. Scholey J. Sorri J. Uusitalo 《The European Physical Journal A - Hadrons and Nuclei》2009,39(3):291-294
The lifetime of the 17/2+ yrast state in 195Po has been measured using the recoil distance Doppler-shift technique to be = 43(11) ps. The lifetime was extracted from the singles -ray spectra obtained by using the recoil-decay tagging method. The present work provides more information of the coupling
schemes, shapes and configuration mixing in neutron-deficient odd-mass Po nuclei. 相似文献
445.
R. -D. Herzberg S. Moon S. Eeckhaudt P. T. Greenlees P. A. Butler T. Page A. V. Afanasjev N. Amzal J. E. Bastin F. Becker M. Bender B. Bruyneel J. F. C. Cocks I. G. Darby O. Dorvaux K. Eskola J. Gerl T. Grahn C. Gray-Jones N. J. Hammond K. Hauschild P. -H. Heenen K. Helariutta A. Herzberg F. Hessberger M. Houry A. Hürstel R. D. Humphreys G. D. Jones P. M. Jones R. Julin S. Juutinen H. Kankaanp?? H. Kettunen T. L. Khoo W. Korten P. Kuusiniemi Y. LeCoz M. Leino A. -P. Lepp?nen C. J. Lister R. Lucas M. Muikku P. Nieminen M. Nyman R. D. Page T. Page J. Pakarinen A. Pritchard P. Rahkila P. Reiter M. Sandzelius J. Saren Ch. Schlegel C. Scholey Ch. Theisen W. H. Trzaska J. Uusitalo A. Wiens H. J. Wollersheim 《The European Physical Journal A - Hadrons and Nuclei》2009,42(3):333-337
In-beam gamma-ray and conversion electron spectroscopic studies have been performed on the 253 No nucleus. A strongly coupled rotational band has been identified and the improved statistics allows an assignment of the band structure as built on the $\ensuremath 9/2^-[734]_{\nu}$ ground state. The results agree with previously known transition energies but disagree with the tentative structural assignments made in earlier work. 相似文献
446.
447.
448.
Measurements have been made, with high statistical accuracy, of the differential scattering cross-section for 1·06 Å neutrons by light water and a special mixture of light and heavy water at 22°C. For light water, the structure in the scattering pattern is attributed mainly to coherent scattering; a structure factor has been obtained over a limited range of momentum transfer. For the chosen mixture, the protons and deuterons give no contribution to the coherent scattering and a structure factor has been obtained which corresponds very well to the oxygen-nucleus structure factor obtained from X-ray data. The results show the desirability of extending these high accuracy measurements using isotopic substitution methods as a means of obtaining the three partial structure factors for water. The method of isotopic mixtures is applicable to a wide range of proton containing liquids. 相似文献
449.
K. V. R. Murthy Y. S. Patel A. S. Sai Prasad V. Natarajan A. G. Page 《Radiation measurements》2003,36(1-6):483-485
The present paper reports studies on the applicability of fluorescent lamp phosphors in accidental radiation dosimetry. Strontium orthophosphate, which is used as one of the components in the fluorescent lamps, has been studied for its thermo-luminescence (TL) characteristics on exposure to different doses of beta irradiation. The analysis of the TL glow curve of the phosphor, with a well-defined glow peak at 553 K, and other experiments carried out have proved the utility of strontium orthophosphate as dosimetric material in the range of 10–200 Gy. It has been observed that the material satisfies most of the fundamental criteria for a good TLD-material. A fluorescent lamp developed with this material as TLD grade lamp phosphor is thus expected to serve twin purposes of providing illumination and monitoring the radiation released during a nuclear accident. 相似文献
450.
EH. Miller und R. W. Page 《Fresenius' Journal of Analytical Chemistry》1903,42(4-5):322-324
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