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Author Vodolazov, D.Y.; Peeters, F.M.
Title Strong influence of nonlocal nonequilibrium effects on the dynamics of the order parameter in a phase-slip center: ring studies Type A1 Journal article
Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 81 Issue 18 Pages 184521,1-184521,7
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We study the influence of the inelastic relaxation time τ̃E of the quasiparticle distribution function f(E) on the phase slip process in quasi-one-dimensional superconducting rings at a temperature close to the critical temperature Tc. We find that the initial time of growth of the order parameter |Δ| in the phase slip core after the phase slip is a nonmonotonic function of τ̃E which has a maximum at τ̃E≃τ̃GL=πℏ/8kB(Tc−T) and has a tendency to saturate for large τ̃E⪢τ̃GL. The effective heating of the electron subsystem due to the increase in |Δ| in the phase slip center together with the above effect result in a nonmonotonic dependence of the number of subsequent phase slips on τ̃E in rings of relatively large radius (in which each phase slip reduces the current density to a small fraction of its initial value). During the phase slip process the order parameter distribution has two peaks near the phase slip core due to the diffusion of the nonequilibrium quasiparticles from that region.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000278141800100 Publication Date (up) 2010-05-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 5 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). D.Y.V. also acknowledges support from the Russian Foundation for Basic Research, Federal Target Programme “Scientific and scientific-pedagogical personnel of innovative Russia in 2009-2013” and Dynasty Foundation. ; Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:83305 Serial 3182
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Author Tsirlin, A.A.; Nath, R.; Abakumov, A.M.; Shpanchenko, R.V.; Geibel, C.; Rosner, H.
Title Frustrated square lattice with spatial anisotropy: crystal structure and magnetic properties of PbZnVO(PO4)2 Type A1 Journal article
Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 81 Issue 17 Pages 174424,1-174424,13
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Crystal structure and magnetic properties of the layered vanadium phosphate PbZnVO(PO4)2 are studied using x-ray powder diffraction, magnetization and specific-heat measurements, as well as band-structure calculations. The compound resembles AA′VO(PO4)2 vanadium phosphates and fits to the extended frustrated square-lattice model with the couplings J1, J1′ between nearest neighbors and J2, J2′ between next-nearest neighbors. The temperature dependence of the magnetization yields estimates of averaged nearest-neighbor and next-nearest-neighbor couplings, J̅ 1≃−5.2 K and J̅ 2≃10.0 K, respectively. The effective frustration ratio α=J̅ 2/J̅ 1 amounts to −1.9 and suggests columnar antiferromagnetic ordering in PbZnVO(PO4)2. Specific-heat data support the estimates of J̅ 1 and J̅ 2 and indicate a likely magnetic ordering transition at 3.9 K. However, the averaged couplings underestimate the saturation field, thus pointing to the spatial anisotropy of the nearest-neighbor interactions. Band-structure calculations confirm the identification of ferromagnetic J1, J1′ and antiferromagnetic J2, J2′ in PbZnVO(PO4)2 and yield (J1′−J1)≃1.1 K in excellent agreement with the experimental value of 1.1 K, deduced from the difference between the expected and experimentally measured saturation fields. Based on the comparison of layered vanadium phosphates with different metal cations, we show that a moderate spatial anisotropy of the frustrated square lattice has minor influence on the thermodynamic properties of the model. We discuss relevant geometrical parameters, controlling the exchange interactions in these compounds and propose a strategy for further design of strongly frustrated square-lattice materials.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000278141600082 Publication Date (up) 2010-05-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 27 Open Access
Notes Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:83384 Serial 1294
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Author Amin-Ahmadi, B.; Aashuri, H.
Title Semisolid structure for M2 high speed steel prepared by cooling slope Type A1 Journal article
Year 2010 Publication Journal of materials processing technology Abbreviated Journal J Mater Process Tech
Volume 210 Issue 12 Pages 1632-1635
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Effects of cooling slope angle and the temperature of molten metal on the globular structure of M2 high speed steel after holding at the semisolid state have been investigated. The globular structure was achieved by pouring the molten metal at 1595 °C on the ceramic cooling slope with the length of 200 mm and the angle of 25°. The globular structure of M2 high speed steel in the form of rolledannealed and as cast condition after holding at semisolid state has been achieved. The size of globular grains of cooling slope sample was smaller than that of the rolledannealed and as cast samples. Solid particles of rolledannealed sample after holding at semisolid state had better roundness compared with cooling slope sample. Dissolution of carbides in the austenite phase at grain boundaries leads to formation of globular particles in the semisolid state. MC-type and M6C-type eutectic carbides reprecipitate during cooling cycle along grain boundaries.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000280498200011 Publication Date (up) 2010-06-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0924-0136; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.147 Times cited 12 Open Access
Notes Approved Most recent IF: 3.147; 2010 IF: 1.570
Call Number UA @ lucian @ c:irua:122042 Serial 2983
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Author Goffin, A.-L.; Duquesne, E.; Raquez, J.-M.; Miltner, H.E.; Ke, X.; Alexandre, M.; Van Tendeloo, G.; van Mele, B.; Dubois, P.
Title From polyester grafting onto POSS nanocage by ring-opening polymerization to high performance polyester/POSS nanocomposites Type A1 Journal article
Year 2010 Publication Journal of materials chemistry Abbreviated Journal J Mater Chem
Volume 20 Issue 42 Pages 9415-9422
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Polyester-grafted polyhedral oligomeric silsesquioxane (POSS) nanohybrids selectively produced by ring-opening polymerization of ε-caprolactone and L,L-lactide (A.-L. Goffin, E. Duquesne, S. Moins, M. Alexandre, Ph. Dubois, Eur. Polym. Journal, 2007, 43, 4103) were studied as masterbatches by melt-blending within their corresponding commercial polymeric matrices, i.e., poly(ε-caprolactone) (PCL) and poly(L,L-lactide) (PLA). For the sake of comparison, neat POSS nanoparticles were also dispersed in PCL and PLA. The objective was to prepare aliphatic polyester-based nanocomposites with enhanced crystallization behavior, and therefore, enhanced thermo-mechanical properties. Wide-angle X-ray scattering and transmission electron microscopy attested for the dispersion of individualized POSS nanoparticles in the resulting nanocomposite materials only when the polyester-grafted POSS nanohybrid was used as a masterbatch. The large impact of such finely dispersed (grafted) nanoparticles on the crystallization behavior for the corresponding polyester matrices was noticed, as evidenced by differential scanning calorimetry analysis. Indeed, well-dispersed POSS nanoparticles acted as efficient nucleating sites, significantly increasing the crystallinity degree of both PCL and PLA matrices. As a result, a positive impact on thermo-mechanical properties was highlighted by dynamic mechanical thermal analysis.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000283264500017 Publication Date (up) 2010-06-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0959-9428;1364-5501; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 42 Open Access
Notes Fwo; Iap-6 Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:85784 Serial 1284
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Author Payette, C.; Amaha, S.; Yu, G.; Gupta, J.A.; Austing, D.G.; Nair, S.V.; Partoens, B.; Tarucha, S.
Title Coherent level mixing in dot energy spectra measured by magnetoresonant tunneling spectroscopy of vertical quantum dot molecules Type A1 Journal article
Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 81 Issue 24 Pages 245310,1-245310,15
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We study by magnetoresonant tunneling spectroscopy single-particle energy spectra of the constituent weakly coupled dots in vertical quantum dot molecules over a wide energy window. The measured energy spectra are well modeled by calculated spectra for dots with in-plane confinement potentials that are elliptical and parabolic in form. However, in the regions where two, three, or four single-particle energy levels are naively expected to cross, we observe pronounced level anticrossing behavior and strong variations in the resonant currents as a consequence of coherent mixing induced by small deviations in the nearly ideal dot confinement potentials. We present detailed analysis of the energy spectra, and focus on two examples of three-level crossings whereby the coherent mixing leads to concurrent suppression and enhancement of the resonant currents when the anticrossing levels are minimally separated. The suppression of resonant current is of particular interest since it is a signature of dark state formation due to destructive interference. We also describe in detail and compare two measurement strategies to reliably extract the resonant currents required to characterize the level mixing.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000278606100003 Publication Date (up) 2010-06-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 6 Open Access
Notes ; We thank A. Bezinger, D. Roth, and M. Malloy for assistance with some of the processing, and K. Ono, T. Kodera, T. Hatano, Y. Tokura, M. Stopa, M. Hilke, G.C. Aers, M. Korkusinski, and R. M. Abolfath for useful discussions. Part of this work is supported by NSERC (Discovery Grant No. 208201), Flemish Science Foundation (FWO-VI), Grant-in-Aid for Scientific Research S (Grant No. 191040070), B (Grant No. 18340081), and by Special Coordination Funds for Promoting Science and Technology, and MEXT. S.T. acknowledges support from QuEST program (BAA-0824). ; Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:83095 Serial 379
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Author Neek-Amal, M.; Peeters, F.M.
Title Nanoindentation of a circular sheet of bilayer graphene Type A1 Journal article
Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 81 Issue 23 Pages 235421,1-235421,6
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Nanoindentation of bilayer graphene is studied using molecular-dynamics simulations. We compared our simulation results with those from elasticity theory as based on the nonlinear Föppl-Hencky equations with rigid boundary condition. The force-deflection values of bilayer graphene are compared to those of monolayer graphene. Youngs modulus of bilayer graphene is estimated to be 0.8 TPa which is close to the value for graphite. Moreover, an almost flat bilayer membrane at low temperature under central load has a 14% smaller Youngs modulus as compared to the one at room temperature.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000278710800003 Publication Date (up) 2010-06-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 108 Open Access
Notes ; We gratefully acknowledge comments from R. Asgari. M.N.-A. would like to thank the Universiteit of Antwerpen for its hospitality where part of this work was performed. This work was supported by the Flemish science foundation (FWO-V1) and the Belgium Science Policy (IAP). ; Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:83093 Serial 2259
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Author Geurts, R.; Milošević, M.V.; Peeters, F.M.
Title Vortex matter in mesoscopic two-gap superconducting disks: influence of Josephson and magnetic coupling Type A1 Journal article
Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 81 Issue 21 Pages 15
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000278846600001 Publication Date (up) 2010-06-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 89 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vlaanderen), the Belgian Science Policy (IAP), the ESF “Nanoscience and Engineering in Superconductivity” (NES) program, and the ESF “Arrays of Quantum Dots and Josephson Junctions” network. ; Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:83933 Serial 3872
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Author Khalil-Allafi, J.; Amin-Ahmadi, B.; Zare, M.
Title Biocompatibility and corrosion behavior of the shape memory NiTi alloy in the physiological environments simulated with body fluids for medical applications Type A1 Journal article
Year 2010 Publication Materials science and engineering: part C: biomimetic materials Abbreviated Journal Mat Sci Eng C-Mater
Volume 30 Issue 8 Pages 1112-1117
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Due to unique properties of NiTi shape memory alloys such as high corrosion resistance, biocompatibility, super elasticity and shape memory behavior, NiTi shape memory alloys are suitable materials for medical applications. Although TiO2 passive layer in these alloys can prevent releasing of nickel to the environment, high nickel content and stability of passive layer in these alloys are very debatable subjects. In this study a NiTi shape memory alloy with nominal composition of 50.7 atom% Ni was investigated by corrosion tests. Electrochemical tests were performed in two physiological environments of Ringer solution and NaCl 0.9% solution. Results indicate that the breakdown potential of the NiTi alloy in NaCl 0.9% solution is higher than that in Ringer solution. The results of Scanning Electron Microscope (SEM) reveal that low pitting corrosion occurred in Ringer solution compared with NaCl solution at potentiostatic tests. The pH value of the solutions increases after the electrochemical tests. The existence of hydride products in the X-ray diffraction analysis confirms the decrease of the concentration of hydrogen ion in solutions. Topographical evaluations show that corrosion products are nearly same in all samples. The biocompatibility tests were performed by reaction of mouse fibroblast cells (L929). The growth and development of cells for different times were measured by numbering the cells or statistics investigations. The figures of cells for different times showed natural growth of cells. The different of the cell numbers between the test specimen and control specimen was negligible; therefore it may be concluded that the NiTi shape memory alloy is not toxic in the physiological environments simulated with body fluids.
Address
Corporate Author Thesis
Publisher Place of Publication Lausanne Editor
Language Wos 000282905600006 Publication Date (up) 2010-06-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0928-4931; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.164 Times cited 34 Open Access
Notes Approved Most recent IF: 4.164; 2010 IF: 2.180
Call Number UA @ lucian @ c:irua:122039 Serial 242
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Author Neek-Amal, M.; Peeters, F.M.
Title Linear reduction of stiffness and vibration frequencies in defected circular monolayer graphene Type A1 Journal article
Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 81 Issue 23 Pages 11
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000279336000001 Publication Date (up) 2010-06-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 44 Open Access
Notes ; Financial support was provided by the Hungarian Research Foundation (Contracts No. OTKA K68312, No. K77771, No. K73361, and No. F68726). ; Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:83857 Serial 1820
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Author Khalil-Allafi, J.; Amin-Ahmadi, B.
Title Multiple-step martensitic transformations in the Ni51Ti49 single crystal Type A1 Journal article
Year 2010 Publication Journal of materials science Abbreviated Journal J Mater Sci
Volume 45 Issue 23 Pages 6440-6445
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Multiple-step martensitic transformations of an aged Ni51Ti49 single crystal using calorimetric method were investigated. Results show that for short aging times (1045 min) multiple-step martensitic transformations on cooling occur in two steps. Applying intermediate aging times (1.254 h) results in three steps and long aging times (more than 8 h) lead to two-step martensitic transformations again. This behavior has not been recognized in NiTi single crystals in literatures. It can be related to the heterogeneity of composition and stress fields around Ni4Ti3 precipitates.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000282429400021 Publication Date (up) 2010-06-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-2461;1573-4803; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.599 Times cited 5 Open Access
Notes Approved Most recent IF: 2.599; 2010 IF: 1.859
Call Number UA @ lucian @ c:irua:122046 Serial 2231
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Author Cortes-Gil, R.; Parker, D.R.; Pitcher, M.J.; Hadermann, J.; Clarke, S.J.
Title Indifference of superconductivity and magnetism to size-mismatched cations in the layered iron arsenides Ba1-xNaxFe2As2 Type A1 Journal article
Year 2010 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 22 Issue 14 Pages 4304-4311
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The evolution of the structure, magnetic ordering, and superconductivity in the series Ba(1-x)Na(x)Fe(2)As(2) is reported up to the limiting Na-rich composition with x = 0.6; the more Na-rich compositions are unstable at high temperatures with respect to competing phases. The magnetic and superconducting behaviors of the Bai,Na,Fe,As, members are similar to those of the betterinvestigated Ba(1-x)Na(x)Fe(2)As(2) analogues. This is evidently a consequence of the quantitatively similar evolution of the structure of the FeAs layers in the two series. In Ba(1-x)Na(x)Fe(2)As(2) antiferromagnetic order and an associated structural distortion are evident for x <= 0.35 and superconductivity is evident when x exceeds 0.2. For 0.4 <= x <= 0.6 bulk superconductivity is evident, and the long-range antiferromagnetically ordered state is completely suppressed. The maximum T(c) in the Ba(1-x)Na(x)Fe(2)As(2) series, as judged by the onset of diamagnetism, is 34K in Ba(0.6)Na(0.4)Fe(2)As(2). Despite the large mis-match in sizes between the two electropositive cations which separate the FeAs layers, there is no evidence for ordering of these cations on the length scale probed by electron diffraction.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000280005300027 Publication Date (up) 2010-07-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 31 Open Access
Notes Approved Most recent IF: 9.466; 2010 IF: 6.400
Call Number UA @ lucian @ c:irua:95594 Serial 1601
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Author Roet, D.; van Espen, P.
Title Monte Carlo simulation of X-ray spectra from low energy electrons using optical data Type A1 Journal article
Year 2010 Publication Nuclear instruments and methods in physics research: B: beam interactions with materials and atoms Abbreviated Journal
Volume 268 Issue 17/18 Pages 2794-2800
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract An approach using optical data to simulate both the bremsstrahlung continuum and characteristic K and L X-ray lines generated by low energy electrons (cfr. electron microscopy) in solids is discussed in this paper. The necessary analytical expressions together with the data to calculate the relevant cross sections for elastic and inelastic interactions at these energies along with variance reduction techniques are given. The results of the Monte Carlo simulation are compared to experimental data measured with a JEOL 6300 electron microscope.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000281498900039 Publication Date (up) 2010-07-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-583x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:84261 Serial 8281
Permanent link to this record
 
 
Author Liu, Y.; Cheng, F.; Li, X.J.; Peeters, F.M.; Chang, K.
Title Tuning of the two electron states in quantum rings through the spin-orbit interaction Type A1 Journal article
Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 82 Issue 4 Pages 1-7
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The effect of the Coulomb interaction on the energy spectrum and anisotropic distribution of two electron states in a quantum ring in the presence of Rashba spin-orbit interaction (RSOI) and Dresselhaus SOI (DSOI) is investigated in the presence of a perpendicular magnetic field. We find that the interplay between the RSOI and DSOI makes the single quantum ring behaves like a laterally coupled quantum dot and the interdot coupling can be tuned by changing the strengths of the SOIs. The interplay can lead to singlet-triplet state mixing and anticrossing behavior when the singlet and triplet states meet with increasing magnetic field. The two electron ground state displays a bar-bell-like spatial anisotropic distribution in a quantum ring at a specific crystallographic direction, i.e., [110] or [11̅ 0], which can be switched by reversing the direction of the perpendicular electric field. The ground state exhibits a singlet-triplet state transition with increasing magnetic field and strengths of RSOI and DSOI. An anisotropic electron distribution is predicted which can be detected through the measurement of its optical properties.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000280234100006 Publication Date (up) 2010-07-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 14 Open Access
Notes ; This work was supported by NSFC under Grants No. 60525405 and No. 10874175 and the Belgium Science Policy (IAP). ; Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:84087 Serial 3756
Permanent link to this record
 
 
Author Maignan, A.; Lebedev, O.I.; Van Tendeloo, G.; Martin, C.; Hebert, S.
Title Metal to insulator transition in the n-type hollandite vanadate Pb1.6V8O16 Type A1 Journal article
Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 82 Issue 3 Pages 035122, 1-035122,5
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The transport and magnetic measurements of polycrystalline Pb1.6V8O16 hollandite reveal a concomitant metal to insulator and antiferromagnetic transition at TMI≈140 K. A clear localization is found below TMI, evidenced by a rapid increase in the absolute value of the negative Seebeck coefficient. The structural study by x-ray and transmission electron microscopy confirms the hollandite structure and shows that no structural transition occurs at TMI, ruling out a possible charge orbital ordering. The negative Seebeck coefficient observed from 50 K up to 900 K, with values reaching S=−38 μV K−1 at 900 K, is explained by the electron doping of ∼1.4e− in the V empty t2g orbitals responsible for the bad metal resistivity (ρ900 K∼2 mΩ cm). As this S value is close to that obtained by considering only the spin and orbital degeneracies, it is expected that |S| for such vanadates will not be sensitive at high temperature to the t2g band filling
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000280366300002 Publication Date (up) 2010-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 10 Open Access
Notes Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:84065 Serial 2009
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Author Yang, C.H.; Peeters, F.M.; Xu, W.
Title Landau-level broadening due to electron-impurity interaction in graphene in strong magnetic fields Type A1 Journal article
Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 82 Issue 7 Pages 075401:1-075401:6
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The effect of electron-impurity and electron-electron interactions on the energy spectrum of electrons moving in graphene is investigated in the presence of a high magnetic field. We find that the width of the broadened Landau levels exhibits an approximate 1/B dependence near half filling for charged impurity scattering. The Landau-level width, the density of states, and the Fermi energy exhibit an oscillatory behavior as a function of magnetic field. Comparison with experiment shows that scattering with charged impurities cannot be the main scattering mechanism that determines the width of the Landau levels.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000280553700008 Publication Date (up) 2010-08-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 38 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), the National Science Foundation of China under Grant No. 10804053, the Foundation of NUIST under Grant No. S8108062001, and the Chinese Academy of Sciences and Department of Science and Technology of Yunnan Province. ; Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:84043 Serial 1769
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Author Ao, Z.M.; Peeters, F.M.
Title Electric field activated hydrogen dissociative adsorption to nitrogen-doped graphene Type A1 Journal article
Year 2010 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 114 Issue 34 Pages 14503-14509
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Graphane, hydrogenated graphene, was very recently synthesized and predicted to have great potential applications. In this work, we propose a new promising approach for hydrogenation of graphene based on density functional theory (DFT) calculations through the application of a perpendicular electric field after substitutionally doping by nitrogen atoms. These DFT calculations show that the doping by nitrogen atoms into the graphene layer and applying an electrical field normal to the graphene surface induce dissociative adsorption of hydrogen. The dissociative adsorption energy barrier of an H2 molecule on a pristine graphene layer changes from 2.7 to 2.5 eV on N-doped graphene, and to 0.88 eV on N-doped graphene under an electric field of 0.005 au. When increasing the electric field above 0.01 au, the reaction barrier disappears. Therefore, N doping and applying an electric field have catalytic effects on the hydrogenation of graphene, which can be used for hydrogen storage purposes and nanoelectronic applications.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000281129100027 Publication Date (up) 2010-08-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447;1932-7455; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 110 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-VI) and the Belgian Science Policy (IAP). ; Approved Most recent IF: 4.536; 2010 IF: 4.524
Call Number UA @ lucian @ c:irua:84588 Serial 882
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Author Ding, F.; Akopian, N.; Li, B.; Perinetti, U.; Govorov, A.; Peeters, F.M.; Bufon, C.C.; Deneke, C.; Chen, Y.H.; Rastelli, A.; Schmidt, O.G.; Zwiller, V.
Title Gate controlled Aharonov-Bohm-type oscillations from single neutral excitons in quantum rings Type A1 Journal article
Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 82 Issue 7 Pages 8
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000280813100005 Publication Date (up) 2010-08-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 58 Open Access
Notes ; We acknowledge L. P. Kouwenhoven and Z. G. Wang for support, L. Wang, V. Fomin, S. Kiravittaya, M. Tadic, Wen-Hao Chang, I. Sellers, A. Avetisyan, and C. Pryor for fruitful discussions and the financial support of NWO (VIDI), the CAS-MPG program, the DFG (FOR730), BMBF (Grant No. 01BM459), NSFC (Grant No. 60625402), and Flemish Science Foundation (FWO-V1). Access to the TEM of B. Rellinghaus is acknowledged. ; Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:83992 Serial 1321
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Author Tsirlin, A.A.; Abakumov, A.M.; Van Tendeloo, G.; Rosner, H.
Title Interplay of atomic displacement in the quantum magnet (CuCI)LaNb2O7 Type A1 Journal article
Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 82 Issue 5 Pages 054107,1-054107,12
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We report on the crystal structure of the quantum magnet CuClLaNb2O7 that was controversially described with respect to its structural organization and magnetic behavior. Using high-resolution synchrotron powder x-ray diffraction, electron diffraction, transmission electron microscopy, and band-structure calculations, we solve the room-temperature structure of this compound -CuClLaNb2O7 and find two high-temperature polymorphs. The -CuClLaNb2O7 phase, stable above 640 K, is tetragonal with asub=3.889 Å, csub =11.738 Å, and the space group P4/mmm. In the -CuClLaNb2O7 structure, the Cu and Cl atoms are randomly displaced from the special positions along the 100 directions. The phase asub2asubcsub, space group Pbmm and the phase 2asub2asubcsub, space group Pbam are stable between 640 K and 500 K and below 500 K, respectively. The structural changes at 500 and 640 K are identified as order-disorder phase transitions. The displacement of the Cl atoms is frozen upon the → transformation while a cooperative tilting of the NbO6 octahedra in the phase further eliminates the disorder of the Cu atoms. The low-temperature -CuClLaNb2O7 structure thus combines the two types of the atomic displacements that interfere due to the bonding between the Cu atoms and the apical oxygens of the NbO6 octahedra. The precise structural information resolves the controversy between the previous computation-based models and provides the long-sought input for understanding CuClLaNb2O7 and related compounds with unusual magnetic properties.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000280849400001 Publication Date (up) 2010-08-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 13 Open Access
Notes Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:83991 Serial 1706
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Author Neek-Amal, M.; Peeters, F.M.
Title Graphene nanoribbons subjected to axial stress Type A1 Journal article
Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 82 Issue 8 Pages 085432-085432,6
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Atomistic simulations are used to study the bending of rectangular graphene nanoribbons subjected to axial stress both for free boundary and supported boundary conditions. The shapes of the deformations of the buckled graphene nanoribbons, for small values of the stress, are sine waves where the number of nodal lines depend on the longitudinal size of the system and the applied boundary condition. The buckling strain for the supported boundary condition is found to be independent of the longitudinal size and estimated to be 0.86%. From a calculation of the free energy at finite temperature we find that the equilibrium projected two-dimensional area of the graphene nanoribbon is less than the area of a flat sheet. At the optimum length the boundary strain for the supported boundary condition is 0.48%.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000281065100007 Publication Date (up) 2010-08-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 92 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). ; Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:84583 Serial 1373
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Author Pogosov, W.V.; Misko, V.R.; Peeters, F.M.
Title Geometry-induced localization of thermal fluctuations in ultrathin superconducting structures Type A1 Journal article
Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 82 Issue 5 Pages 054523-054523,6
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Thermal fluctuations of the order parameter in an ultrathin triangular-shaped superconducting structure are studied near Tc, in zero applied field. We find that the order parameter is prone to much larger fluctuations in the corners of the structure as compared to its interior. This geometry-induced localization of thermal fluctuations is attributed to the fact that condensate confinement in the corners is characterized by a lower effective dimensionality, which favors stronger fluctuations.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000281294700006 Publication Date (up) 2010-08-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 2 Open Access
Notes ; This work was supported by the “Odysseus” Program of the Flemish government, FWO-Vl, and the Belgian Science Policy (IAP). W. V. P. acknowledges supports from the RFBR [Project No. 09-02-00248] and the “Dynasty Foundation.” ; Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:84470 Serial 1334
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Author Afanasov, I.M.; Van Tendeloo, G.; Mateev, A.T.
Title Production and structure of exfoliated graphite/coke composites modified by ZrO2 nanoparticles Type A1 Journal article
Year 2010 Publication New carbon materials Abbreviated Journal
Volume 25 Issue 4 Pages 255-260
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Exfoliated graphite/coke composites modified by ZrO2 nanoparticles were produced using two different techniques and characterized by means of X-ray diffraction, scanning and transmission electron microscopy. In the first, low-density exfoliated graphite/coke blocks were dipped repeatedly and alternately in ZrO(NO3)2 and NH4OH solutions and subsequently heat treated at 1200°C in nitrogen to deposit thin layers of ZrO2 nanoparticles on the free surfaces of the carbon matrix. In the second, a mixture of expandable graphite, phenol-formaldehyde resin powder, and ZrOC2O4-modified fibrous cellulose in a sealed container was submitted to thermal shock at 900 °C followed by heat treatment at 1 200 °C in nitrogen to obtain the modified composites. The ZrO2 nanoparticles formed in the second technique were incorporated into the composites in three length scales: 6-30 nm-isolated nanoparticles and small blobs, 200-1000 nm-lengthy dendrite-like structures, and thin layer adhering to the surface of the 1-40 μm long cellulose carbon fibers.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000281534800003 Publication Date (up) 2010-09-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1872-5805; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Iap-Vi Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:84438 Serial 2721
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Author Xu, W.; Dong, H.M.; Li, L.L.; Yao, J.Q.; Vasilopoulos, P.; Peeters, F.M.
Title Optoelectronic properties of graphene in the presence of optical phonon scattering Type A1 Journal article
Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 82 Issue 12 Pages 125304-125304,9
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We study in detail the optoelectronic properties of graphene. Considering the electron interactions with photons and phonons, we employ the mass- and energy-balance equations to self-consistently evaluate the photoinduced carrier densities, the optical conductance, and the transmission coefficient in the presence of a linearly polarized radiation field. We demonstrate that the photoinduced carrier densities increase around the electron-photon-phonon resonant transition. They depend strongly on the radiation intensity and frequency, temperature, and dark carrier density. For short-wavelength radiation (L<3 μm), we obtain the universal optical conductance σ0=e2/(4ℏ). Importantly, there exists an optical-absorption window in the radiation wavelength range 4100 μm, which is induced by different transition energies required for interband and intraband optical absorption. The position and width of this window depend sensitively on the temperature and the carrier density of the system. These theoretical results are in line with recent experimental findings and indicate that graphene exhibits important features not only in the visible regime but also in the midinfrared bandwidth.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000281516500009 Publication Date (up) 2010-09-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 28 Open Access
Notes ; This work was supported by the Chinese Academy of Sciences, National Natural Science Foundation of China, and Department of Science and Technology of Yunnan Province. ; Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:84260 Serial 2496
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Author Földi, P.; Szaszkó-Bogár, V.; Peeters, F.M.
Title Spin-orbit interaction controlled properties of two-dimensional superlattices Type A1 Journal article
Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 82 Issue 11 Pages 115302-115302,4
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The band structure of two-dimensional artificial superlattices in the presence of (Rashba-type) spin-orbit interaction (SOI) is presented. The position and shape of the energy bands in these spintronic crystals depend on the geometry as well as the strength of the SOI, which can be tuned by external gate voltages. For finite mesoscopic arrays, we show that their conductance properties and possible applications can be understood from these spin-dependent band diagrams.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000281516300005 Publication Date (up) 2010-09-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 6 Open Access
Notes ; We thank M. G. Benedict and F. Bartha for useful discussions. This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP) and the Hungarian Scientific Research Fund (OTKA) under Contracts No. T81364 and No. M045596. P.F. was supported by a J. Bolyai grant of the Hungarian Academy of Sciences. ; Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:84259 Serial 3092
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Author Gehrke, K.; Moshnyaga, V.; Samwer, K.; Lebedev, O.I.; Verbeeck, J.; Kirilenko, D.; Van Tendeloo, G.
Title Interface controlled electronic variations in correlated heterostructures Type A1 Journal article
Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 82 Issue 11 Pages 113101,1-113101,4
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract An interface modification of (LaCa)MnO3-BaTiO3 superlattices was found to massively influence magnetic and magnetotransport properties. Moreover it determines the crystal structure of the manganite layers, changing it from orthorhombic (Pnma) for the conventional superlattice (cSL), to rhombohedral (R3̅ c) for the modified one (mSL). While the cSL shows extremely nonlinear ac transport, the mSL is an electrically homogeneous material. The observations go beyond an oversimplified picture of dead interface layers and evidence the importance of electronic correlations at perovskite interfaces.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000281643200001 Publication Date (up) 2010-09-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 9 Open Access
Notes This work was supported by DFG via SFB 602, TPA2. Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:84249UA @ admin @ c:irua:84249 Serial 1691
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Author Jain, R.; Rather, J.A.; Dwivedi, A.
Title Voltammetric behaviour of nitroxazepine in solubilized system and biological fluids Type A1 Journal article
Year 2011 Publication Materials science and engineering: part C: biomimetic materials Abbreviated Journal
Volume 31 Issue 2 Pages 230-237
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract This study reports the development and validation of sensitive and selective assay method for the determination of the antidepressant drug in solubilized system and biological fluids. Solubilized system of different surfactants including cationic, anionic and non-ionic influences the electrochemical response of drug. Addition of cationic surfactant cetrimide to the solution containing drug enhances the peak current signal while anionic and non-ionic showed an opposite effect. The current signal due to reduction process was function of concentration of nitroxazepine, pH, type of surfactant and preconcentration time at the electrode surface. The reduction process is irreversible and adsorption controlled at HMDE. Various chemical and instrumental parameters affecting the monitored electroanalytical response were investigated and optimized for niroxazepine hydrochloride determination. The proposed SWCAdSV and DPCAdSV methods are linear over the concentration range 2.0 × 10-7 5.0 × 10-9 mol/L and 6.1 × 10-7 1.0 × 10-8 mol/L with detection limit of 1.62 × 10-10 mo/L and 1.4 × 10-9 mo/L respectively. The method shows good sensitivity, selectivity, accuracy and precision that makes it very suitable for determination of nitroxazepine in pharmaceutical formulation and biological fluids.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000286707900024 Publication Date (up) 2010-09-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0928-4931 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:98685 Serial 8743
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Author Masir, M.R.; Vasilopoulos, P.; Peeters, F.M.
Title Fabry-Pérot resonances in graphene microstructures: influence of a magnetic field Type A1 Journal article
Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 82 Issue 11 Pages 115417-115417,12
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Fabry-Pérot resonances in the transmission through single and double, graphene-based barriers (of height V) and wells are investigated and their dependence on an applied perpendicular magnetic field. For rectangular barriers the conductance decreases with increasing magnetic field while the resonances weaken (become more pronounced) with increasing magnetic field for EF<V (EF>V). The position of the resonances exhibit a linear shift with magnetic field which move to lower (higher) energy for EF<V (EF>V). Compared to semielliptic- or Gaussian-shaped barriers they show a smaller number of resonances in the absence of a magnetic field and an overall lower conductance but the resonant structure is more pronounced. The conductance of asymmetric double barriers show two major regions of resonances while the symmetric ones show one, that of three asymmetric barriers three, and so on.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000281723100007 Publication Date (up) 2010-09-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 74 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP) and the Canadian NSERC under Grant No. OGP0121756. ; Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:84871 Serial 1167
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Author van den Heuvel, W.; Tikhomirov, V.K.; Kirilenko, D.; Schildermans, N.; Chibotaru, L.F.; Vanacken, J.; Gredin, P.; Mortier, M.; Van Tendeloo, G.; Moshchalkov, V.V.
Title Ultralow blocking temperature and breakdown of the giant spin model in Er3+-doped nanoparticles Type A1 Journal article
Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 82 Issue 9 Pages 094421-094421,8
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The magnetization of luminescent Er3+-doped PbF2 nanoparticles (formula Er0.3Pb0.7F2.3) has been studied. Despite the high concentration of the doping Er3+ ions and relatively large size (8 nm) of these nanoparticles we have found no deviation between field-cooled and zero-field-cooled magnetization curves down to T=0.35 K, which points out an ultralow blocking temperature for the reversal of magnetization. We also have found strongly deviating magnetization curves M(H/T) for different temperatures T. These results altogether show that the investigated nanoparticles are not superparamagnetic, but rather each Er3+ ion in these nanoparticles is found in a paramagnetic state down to very low temperatures, which implies the breakdown of the Néel-Brown giant spin model in the case of these nanoparticles. Calculations of magnetization within a paramagnetic model of noninteracting Er3+ ions completely support this conclusion. Due to the ultralow blocking temperature, these nanoparticles have a potential for magnetic field-induced nanoscale refrigeration with an option of their optical localization and temperature control.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000281773300005 Publication Date (up) 2010-09-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 11 Open Access
Notes Fwo Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:85423 Serial 3796
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Author Tsvyashchenko, A.V.; Nikolaev, A.V.; Velichkov, A.I.; Salamatin, A.V.; Fomicheva, L.N.; Ryasny, G.K.; Sorokin, A.A.; Kochetov, O.I.; Budzynski, M.; Michel, K.H.
Title Lowering of the spatial symmetry at the gamma ->alpha phase transition in cerium Type A1 Journal article
Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 82 Issue 9 Pages 1-4
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using time-differential perturbed angular correlation spectroscopy we have measured the electric field gradient (EFG) at 111Cd probe nuclei in solid Ce in a pressure range up to 8 GPa. Covering various allotropic phases of Ce, we find that the value of the EFG in the cubic α phase is almost four times larger than in the cubic γ phase and close to values in the noncubic phases α′ and α″. These results together with the differences in time modulation of the spectra are interpreted as evidence for quadrupolar electronic charge-density ordering and symmetry lowering at the γ→α transition while the lattice remains face-centered cubic
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000282004400001 Publication Date (up) 2010-09-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 11 Open Access
Notes ; This work is supported by the Program of the Presidium of the Russian Academy of Sciences “Physics of Strongly Compressed Matter.” We are grateful to S. M. Stishov, B. Verberck, A. N. Grum-Grzhimailo, V. B. Brudanin and G. Heger for support of this work and discussion of the results. ; Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:85464 Serial 1854
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Author Burriel, M.; Casa-Cabanas, M.; Zapata, J.; Tan, H.; Verbeeck, J.; Solis, C.; Roqueta, J.; Skinner, S.J.; Kilner, J.A.; Van Tendeloo, G.; Santiso, J.
Title Influence of the microstructure on the high-temperature transport properties of GdBaCo2O5.5+\delta epitaxial films Type A1 Journal article
Year 2010 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 22 Issue 19 Pages 5512-5520
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Epitaxial thin films of GdBaCo2O5.5+δ (GBCO) grown by pulsed laser deposition have been studied as a function of deposition conditions. The variation in film structure, domain orientation, and microstructure upon deviations in the cation composition have been correlated with the charge transport properties of the films. The epitaxial GBCO films mainly consist of single- and double-perovskite regions that are oriented in different directions depending on the deposition temperature. Additionally, cobalt depletion induces the formation of a high density of stacking defects in the films, consisting of supplementary GdO planes along the c-axis of the material. The presence of such defects progressively reduces the electrical conductivity. The films closer to the stoichiometric composition have shown p-type electronic conductivity at high pO2 with values as high as 800 S/cm at 330 °C in 1 atm O2, and with a pO2 power dependence with an exponent as low as 1/25, consistent with the behavior reported for bulk GBCO. These values place GBCO thin films as a very promising material to be applied as cathodes in intermediate temperature solid oxide fuel cells.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000282471000013 Publication Date (up) 2010-09-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 17 Open Access
Notes Fwo; Esteem 026019 Approved Most recent IF: 9.466; 2010 IF: 6.400
Call Number UA @ lucian @ c:irua:85412UA @ admin @ c:irua:85412 Serial 1648
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Author Čevik, U.; Damla, N.; Van Grieken, R.; Vefa Akpinar, M.
Title Chemical composition of building materials used in Turkey Type A1 Journal article
Year 2011 Publication Construction and building materials Abbreviated Journal
Volume 25 Issue 4 Pages 1546-1552
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract The main goal of this work was to determine the chemical composition of building materials used in Turkey by utilizing energy dispersive X-ray fluorescence (EDXRF) spectrometry. Gas concrete, cement, sand, bricks, roofing tiles, marble, lime and gypsum materials were selected as building materials for this research. The chemical contents and their trace concentrations of the selected samples were determined. The most abundant oxides measured were generally SiO2, Al2O3, CaO, MgO, Fe2O3, K2O and SO3 for all samples. While the main chemical component of gas concrete, cement, sand and marble samples were SiO2 and CaO, brick and roofing tile mainly consisted of SiO2 and Al2O3. CaO and SO3 were major component of lime and gypsum samples, respectively. For U and Th concentrations in the samples, activities of 226Ra and 232Th were measured by utilizing gamma spectrometry. ANOVA and Pearson correlation analyses were performed on the studied data for statistical analysis.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000287379300007 Publication Date (up) 2010-09-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0950-0618 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:86448 Serial 7653
Permanent link to this record