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991.
992.
Afrodita Liliana Boldea 《Central European Journal of Physics》2010,8(6):995-1000
The paper presents a concrete study of the existence of generalized and potential symmetries for the 1+1 dimensional version
of the Rudenko-Robsman equation, an interesting fourth-order partial differential equation that describes the evolution of
nonlinear waves in a dispersive medium. As the main results, the existence of a two-parameter algebra of generalized symmetries
and of an infinite-dimensional algebra when potential symmetries are taken into account is proven. 相似文献
993.
Agnieszka Grzelińska 《中国物理C(英文版)》2010,34(6)
We discuss interference effects important for the form factors extraction in the vicinity of J/ψ andψ(2S)resonances in combination with resonance parameters determination.The implementation to the Monte Carlo event generator PHOKHARA of the J/ψ and ψ(2S)contributions to the muon,pion and kaon pairs production associated with a photon at next-to-leading order is also described. 相似文献
994.
?. T. St?pień 《Physics of Particles and Nuclei》2010,41(6):987-989
Some classes of exact solutions of scalar Born-Infeld equation have been found. Certain selected properties of these solutions
have been presented. 相似文献
995.
In this paper we present a design of a compact, low power diode-pumped CW Nd:YAG laser operating at 946 nm with intracavity
blue light generation at 473 nm for battery operated applications. The nonlinear crystal used in the experiment is a BiBO
crystal cut for phase-matching type I. Using 0.8 W of pumping power, 20-mW stabile output power of blue light was achieved.
The second harmonic generation conversion efficiency was 2.5%. 相似文献
996.
A. Chru?cińska 《Radiation measurements》2010,45(9):991-999
The influence of electron–phonon interaction on the shape of the optically stimulated luminescence decay curve has been examined. The formula describing the dependence of optical cross-section on stimulation energy and temperature has been applied in a computer simulation of optically stimulated luminescence process. Computer simulations have been carried out for different temperatures using both one-trap and two-trap models. The ideas of an OSL measurement with continuously increasing energy of stimulation have been tested via computer simulations. The outcomes of this technique have been presented for a wide range of material parameters. 相似文献
997.
HfO2 and HfO2:Eu powders were synthesized with Pechini method at temperatures in the range of 600–1500 °C. Structural, radioluminescence and photoluminescence properties of the powders were investigated. The highest light output of about 20% of the efficiency of commercial GOS:Eu was found for materials containing 0.5% of Eu and prepared at 1500 °C. The data shows, that further improvement of light output could be obtained if materials are processed at yet higher temperatures. Emission spectra indicate that Eu3+ experiences variety of symmetries of its surroundings. Undoped materials produce broad band emission peaking at 480 nm and showing a significant afterglow. 相似文献
998.
L. Stolarczyk P. Olko T. Cywicka-Jakiel M. Ptaszkiewicz J. Swakoń B. Dulny T. Horwacik B. Obryk M.P.R. Waligórski 《Radiation measurements》2010,45(10):1441-1444
Radiotherapy with a proton beam of initial energy 55–80 MeV is presently the clinically recommended therapy for some cases of intraocular melanoma such as large melanomas or tumours adjacent to critical organs. Evaluation and optimization of radiation doses outside the treatment volume may contribute to reducing undesirable side-effects and decreasing the risk of occurrence of secondary cancers, particularly for paediatric patients. In this work the undesired doses to organs were assessed basing on Monte Carlo calculation of secondary radiation transport and on results of measurements of neutron and γ-ray doses at the proton therapy facility of the Institute of Nuclear Physics at Kraków. Dosimetry was performed using a He-3-based FHT 762 neutron monitor (Wendi II), a FH40G proportional counter (for γ-rays), and MTS-7 (LiF:Mg,Ti) thermoluminescence detectors (TLDs). Organ doses were calculated in the ADAM anthropomorphic phantom using the MCNPX Monte Carlo transport code and partly verified, for γ-ray doses, with TLD measurements in the RANDO Anderson anthropomorphic phantom. The effective dose due to undesired radiation, including exposure from scattered radiation during the entire process of proton radiotherapy and patient positioning using X-rays, does not exceed 1 mSv. 相似文献
999.
P. Moskal R. Czy?ykiewicz E. Czerwiński D. Gil D. Grzonka L. Jarczyk B. Kamys A. Khoukaz J. Klaja P. Klaja W. Krzemień W. Oelert J. Ritman T. Sefzick M. Siemaszko M. Silarski J. Smyrski A. T?schner M. Wolke P. Wüstner J. Zdebik M. J. Zieliński W. Zipper 《The European Physical Journal A - Hadrons and Nuclei》2010,43(2):131-136
Proton-proton and proton- $ \eta$ invariant-mass distributions and the total cross-section for the pp $ \rightarrow$ pp $ \eta$ reaction have been determined near the threshold at an excess energy of Q = 10 MeV. The experiment has been conducted using the COSY-11 detector setup and the cooler synchrotron COSY. The determined invariant-mass spectra reveal significant enhancements in the region of low proton-proton relative momenta, similarly as observed previously at higher excess energies of Q = 15.5 MeV and Q = 40 MeV. 相似文献
1000.
T. Domański 《The European Physical Journal B - Condensed Matter and Complex Systems》2010,74(4):437-445
Development of the STM and ARPES spectroscopy enabled to reach
the resolution sufficient for probing the particle-hole entanglement
in superconducting materials, even above the critical temperature
Tc. On a quantitative level one can characterize such
entanglement in terms of the Bogoliubov angle which determines
to what extent the particles and holes constitute the effective
quasiparticles.
In classical superconductors, where the phase transition is related
to formation of the Cooper pairs almost simultaneously accompanied
by onset of their long-range phase coherence, the Bogoliubov angle
is slanted (due to finite particle-hole mixing) all the way up to Tc.
In the high temperature superconductors and in superfluid ultracold
fermion atoms near the Feshbach resonance the situation is different
because the preformed pairs can exist above Tc albeit
loosing coherence due to the strong quantum fluctuations. We
discuss a generic temperature dependence of the Bogoliubov angle
in such pseudogap state indicating a novel, non-BCS behavior. For
analysis we use the two-component model describing the pairs
coexisting with single fermions and study selfconsistently
their feedback effects by the similarity transformation
originating from the renormalization group approach. 相似文献