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341.
Time-dependent lattice fluctuations of an optically excited strongly confined quantum dot are investigated with the aim to analyze the characteristics commonly used for identifying the presence of squeezed phonon states. It is demonstrated that the appearance of fluctuations oscillating with twice the phonon frequency, commonly regarded as a clear indication of squeezed states, cannot be considered as such. The source of the discrepancy with earlier investigations is discussed. Conditions for generating a squeezed state by using a two-pulse excitation are analyzed. 相似文献
342.
A. Ekstr?m J. Cederk?ll C. Fahlander M. Hjorth-Jensen T. Engeland A. Blazhev P. A. Butler T. Davinson J. Eberth F. Finke A. G?rgen M. Górska A. M. Hurst O. Ivanov J. Iwanicki U. K?ster B. A. Marsh J. Mierzejewski P. Reiter S. Siem G. Sletten I. Stefanescu G. M. Tveten J. Van de Walle D. Voulot N. Warr D. Weisshaar F. Wenander M. Zielińska 《The European Physical Journal A - Hadrons and Nuclei》2010,44(3):355-361
The low-lying states in the odd-odd and unstable isotopes 106, 108In have been Coulomb excited from the ground state and the first excited isomeric state at the REX-ISOLDE facility at CERN. With the additional data provided here the $ \pi$ g 9/2 -1 ? $ \nu$ d 5/2 and $ \pi$ g 9/2 -1 ? $ \nu$ g 7/2 multiplets have been re-analyzed and are modified compared to previous results. The observed $ \gamma$ -ray de-excitation patterns were interpreted within a shell model calculation based on a realistic effective interaction. The agreement between theory and experiment is satisfactory and the calculations reproduce the observed differences in the excitation pattern of the two isotopes. The calculations exclude a 6+ ground state in 106In . This is in agreement with the conclusions drawn using other techniques. Furthermore, based on the experimental results, it is also concluded that the ordering of the isomeric and ground state in 108In is inverted compared to the shell model prediction. Limits on B(E2) values have been extracted where possible. A previously unknown low-lying state at 367keV in 106In is also reported. 相似文献
343.
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
344.
345.
A Long‐Life Lithium Ion Battery with Enhanced Electrode/Electrolyte Interface by Using an Ionic Liquid Solution
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Dr. Giuseppe Antonio Elia Ulderico Ulissi Franziska Mueller Dr. Jakub Reiter Dr. Nikolaos Tsiouvaras Prof. Yang‐Kook Sun Prof. Bruno Scrosati Prof. Stefano Passerini Prof. Jusef Hassoun 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(20):6808-6814
In this paper, we report an advanced long‐life lithium ion battery, employing a Pyr14TFSI‐LiTFSI non‐flammable ionic liquid (IL) electrolyte, a nanostructured tin carbon (Sn‐C) nanocomposite anode, and a layered LiNi1/3Co1/3Mn1/3O2 (NMC) cathode. The IL‐based electrolyte is characterized in terms of conductivity and viscosity at various temperatures, revealing a Vogel–Tammann–Fulcher (VTF) trend. Lithium half‐cells employing the Sn‐C anode and NMC cathode in the Pyr14TFSI‐LiTFSI electrolyte are investigated by galvanostatic cycling at various temperatures, demonstrating the full compatibility of the electrolyte with the selected electrode materials. The NMC and Sn‐C electrodes are combined into a cathode‐limited full cell, which is subjected to prolonged cycling at 40 °C, revealing a very stable capacity of about 140 mAh g?1 and retention above 99 % over 400 cycles. The electrode/electrolyte interface is further characterized through a combination of electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) investigations upon cell cycling. The remarkable performances reported here definitively indicate that IL‐based lithium ion cells are suitable batteries for application in electric vehicles. 相似文献
346.
347.
Cvetelin Vasilev Harry Heinzelmann Günter Reiter 《Journal of Polymer Science.Polymer Physics》2004,42(7):1312-1320
We demonstrate a possibility to create custom‐made surface patterns on multiple length scales by melting selected nano‐meter‐sized polymer crystals confined in a highly ordered, spherical mesostructure of a hydrogenated poly(butadiene‐block‐ethylene oxide) (PBh‐b‐PEO) block copolymer. With heatable probes of an atomic force microscope as a heat source, we succeeded to provide highly locally the thermal energy necessary to individually melt such crystals. Besides this possibility for modification of surface properties, we performed detailed in situ studies of thermally induced reorganization processes and subsequent melting of polymer crystals in confined volumes of a block copolymer mesostructure. Close to the melting point, the stability of the confined crystals could be improved by annealing. In addition, the crystal size increased at the expense of already‐molten crystals, indicating diffusion of PEO blocks across the highly incompatible PBh matrix. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 1312–1320, 2004 相似文献
348.
Sylvain Gabriele Pascal Damman Séverine Sclavons Sylvain Desprez Séverine Coppée Günter Reiter Moustafa Hamieh Samer Al Akhrass Thomas Vilmin Elie Raphaël 《Journal of polymer science. Part A, Polymer chemistry》2006,44(20):3022-3030
Thin films of fluids are playing a leading role in countless natural and industrial processes. Here we study the stability and dewetting dynamics of viscoelastic polymer thin films. The dewetting of polystyrene close to the glass transition reveals unexpected features: asymmetric rims collecting the dewetted liquid and logarithmic growth laws that we explain by considering the nonlinear velocity dependence of friction at the fluid/solid interface and by evoking residual stresses within the film. Systematically varying the time so that films were stored below the glass-transition temperature, we studied simultaneously the probability for film rupture and the dewetting dynamics at early stages. Both approaches proved independently the significance of residual stresses arising from the fast solvent evaporation associated with the spin-coating process. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 3022–3030, 2006 相似文献
349.
350.
Petra Gadler Tamara C. Reiter Kathrin Hoelsch Dirk Weuster-Botz Kurt Faber 《Tetrahedron: Asymmetry》2009,20(1):115-118
Whole resting cells of cyano- and thio-bacteria Synechococcus and Paracoccus spp. were shown to possess inverting alkylsulfatase activity for a broad spectrum of sec-alkylsulfate esters, which furnished either (R)- or (S)-sec-alcohols from the corresponding rac-sulfate esters in an enantiocomplementary fashion. Low enantioselectivities (E-values 1–4) could be dramatically improved by the addition of lower alcohols (e.g., t-BuOH) or by using a biphasic medium containing t-BuOMe (E >200). 相似文献