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Author Gou, H.; Tsirlin, A.A.; Bykova, E.; Abakumov, A.M.; Van Tendeloo, G.; Richter, A.; Ovsyannikov, S.V.; Kurnosov, A.V.; Trots, D.M.; Konôpková, Z.; Liermann, H.P.; Dubrovinsky, L.; Dubrovinskaia, N.;
Title Peierls distortion, magnetism, and high hardness of manganese tetraboride Type A1 Journal article
Year 2014 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 89 Issue 6 Pages 064108-64109
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We report crystal structure, electronic structure, and magnetism of manganese tetraboride, MnB4, synthesized under high-pressure, high-temperature conditions. In contrast to superconducting FeB4 and metallic CrB4, which are both orthorhombic, MnB4 features a monoclinic crystal structure. Its lower symmetry originates from a Peierls distortion of the Mn chains. This distortion nearly opens the gap at the Fermi level, but despite the strong dimerization and the proximity of MnB4 to the insulating state, we find indications for a sizable paramagnetic effective moment of about 1.7 mu(B)/f.u., ferromagnetic spin correlations, and, even more surprisingly, a prominent electronic contribution to the specific heat. However, no magnetic order has been observed in standard thermodynamic measurements down to 2 K. Altogether, this renders MnB4 a structurally simple but microscopically enigmatic material; we argue that its properties may be influenced by electronic correlations.
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Corporate Author Thesis
Publisher Place of Publication (down) Editor
Language Wos 000332405000002 Publication Date 2014-02-24
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 39 Open Access
Notes Approved Most recent IF: 3.836; 2014 IF: 3.736
Call Number UA @ lucian @ c:irua:115819 Serial 2571
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Author Tsirlin, A.A.; Nath, R.; Abakumov, A.M.; Furukawa, Y.; Johnston, D.C.; Hemmida, M.; Krug von Nidda, H.-A.; Loidl, A.; Geibel, C.; Rosner, H.
Title Phase separation and frustrated square lattice magnetism of Na1.5VOPO4F0.5 Type A1 Journal article
Year 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 84 Issue 1 Pages 014429-014429,16
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Crystal structure, electronic structure, and magnetic behavior of the spin-1/2 quantum magnet Na1.5VOPO4F0.5 are reported. The disorder of Na atoms leads to a sequence of structural phase transitions revealed by synchrotron x-ray powder diffraction and electron diffraction. The high-temperature second-order α↔β transition at 500 K is of the order-disorder type, whereas the low-temperature β↔γ+γ′ transition around 250 K is of the first order and leads to a phase separation toward the polymorphs with long-range (γ) and short-range (γ′) order of Na. Despite the complex structural changes, the magnetic behavior of Na1.5VOPO4F0.5 probed by magnetic susceptibility, heat capacity, and electron spin resonance measurements is well described by the regular frustrated square lattice model of the high-temperature α-polymorph. The averaged nearest-neighbor and next-nearest-neighbor couplings are J̅ 1≃−3.7 K and J̅ 2≃6.6 K, respectively. Nuclear magnetic resonance further reveals the long-range ordering at TN=2.6 K in low magnetic fields. Although the experimental data are consistent with the simplified square-lattice description, band structure calculations suggest that the ordering of Na atoms introduces a large number of inequivalent exchange couplings that split the square lattice into plaquettes. Additionally, the direct connection between the vanadium polyhedra induces an unusually strong interlayer coupling having effect on the transition entropy and the transition anomaly in the specific heat. Peculiar features of the low-temperature crystal structure and the relation to isostructural materials suggest Na1.5VOPO4F0.5 as a parent compound for the experimental study of tetramerized square lattices as well as frustrated square lattices with different values of spin.
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Corporate Author Thesis
Publisher Place of Publication (down) Editor
Language Wos 000293247400008 Publication Date 2011-07-28
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 47 Open Access
Notes Approved Most recent IF: 3.836; 2011 IF: 3.691
Call Number UA @ lucian @ c:irua:91770 Serial 2588
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Author Lin, N.S.; Heitmann, T.W.; Yu, K.; Plourde, B.L.T.; Misko, V.R.
Title Rectification of vortex motion in a circular ratchet channel Type A1 Journal article
Year 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 84 Issue 14 Pages 144511-144511,12
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We study the dynamics of vortices in an asymmetric (i.e., consisting of triangular cells) ring channel driven by an external ac current I in a Corbino setup. The asymmetric potential rectifies the motion of vortices and induces a net vortex flow without any unbiased external drive, i.e., the ratchet effect. We show that the net flow of vortices strongly depends on vortex density and frequency of the driving current. Depending on the density, we distinguish a single-vortex rectification regime (for low density, when each vortex is rectified individually) determined by the potential-energy landscape inside each cell of the channel (i.e., hard and easy directions) and multi-vortex, or collective, rectification (high-density case) when the inter-vortex interaction becomes important. We analyze the average angular velocity ω of vortices as a function of I and study commensurability effects between the numbers of vortices and cells in the channel and the role of frequency of the applied ac current. We have shown that the commensurability effect results in a stepwise ω-I curve. Besides the integer steps, i.e., the large steps found in the single-vortex case, we also found fractional steps corresponding to fractional ratios between the numbers of vortices and triangular cells. We have performed preliminary measurements on a device containing a single weak-pinning circular ratchet channel in a Corbino geometry and observed a substantial asymmetric vortex response.
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Corporate Author Thesis
Publisher Place of Publication (down) Editor
Language Wos 000295795500010 Publication Date 2011-10-07
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 27 Open Access
Notes ; We thank Peter Kes and Marcel Hesselberth for providing the superconducting films from which the Corbino ratchet sample was fabricated. This work was supported by the “Odysseus” Program of the Flemish Government and the Flemish Science Foundation (FWO-Vl), the Interuniversity Attraction Poles (IAP) Programme-Belgian State-Belgian Science Policy, and the FWO-Vl (Belgium). T. W. H., K.Y., and B. L. T. P acknowledge support from the National Science Foundation under Grant DMR-0547147 as well as the use of the Cornell NanoScale Facility, a member of the National Nanotechnology Infrastructure Network, which is supported by the National Science Foundation (Grant ECS-0335765). ; Approved Most recent IF: 3.836; 2011 IF: 3.691
Call Number UA @ lucian @ c:irua:92809 Serial 2848
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Author Tsirlin, A.A.; Abakumov, A.M.; Ritter, C.; Henry, P.F.; Janson, O.; Rosner, H.
Title Short-range order of Br and three-dimensional magnetism in (CuBr)LaNb2O7 Type A1 Journal article
Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 85 Issue 21 Pages 214427
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We present a comprehensive study of the crystal structure, magnetic structure, and microscopic magnetic model of (CuBr)LaNb2O7, the Br analog of the spin-gap quantum magnet (CuCl) LaNb2O7. Despite similar crystal structures and spin lattices, the magnetic behavior and even peculiarities of the atomic arrangement in the Cl and Br compounds are very different. The high- resolution x-ray and neutron data reveal a split position of Br atoms in (CuBr) LaNb2O7. This splitting originates from two possible configurations developed by [CuBr] zigzag ribbons. While the Br atoms are locally ordered in the ab plane, their arrangement along the c direction remains partially disordered. The predominant and energetically more favorable configuration features an additional doubling of the c lattice parameter that was not observed in (CuCl) LaNb2O7. (CuBr) LaNb2O7 undergoes long-range antiferromagnetic ordering at T-N = 32 K, which is nearly 70% of the leading exchange coupling J4 similar or equal to 48 K. The Br compound does not show any experimental signatures of low-dimensional magnetism because the underlying spin lattice is three-dimensional. The coupling along the c direction is comparable to the couplings in the ab plane, even though the shortest Cu-Cu distance along c (11.69 angstrom) is three times larger than nearest-neighbor distances in the ab plane (3.55 angstrom). The stripe antiferromagnetic long-range order featuring columns of parallel spins in the ab plane and antiparallel spins along c is verified experimentally and confirmed by the microscopic analysis.
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Corporate Author Thesis
Publisher Place of Publication (down) Editor
Language Wos 000305557600002 Publication Date 2012-06-22
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 5 Open Access
Notes Approved Most recent IF: 3.836; 2012 IF: 3.767
Call Number UA @ lucian @ c:irua:100289 Serial 2998
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Author Abakumov, A.M.; Tsirlin, A.A.; Perez-Mato, J.M.; Petřiček, V.; Rosner, H.; Yang, T.; Greenblatt, M.
Title Spiral ground state against ferroelectricity in the frustrated magnet BiMnFe2O6 Type A1 Journal article
Year 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 83 Issue 21 Pages 214402-214402,10
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The spiral magnetic structure and underlying spin lattice of BiMnFe2O6 are investigated by low-temperature neutron powder diffraction and density functional theory band structure calculations. In spite of the random distribution of the Mn3+ and Fe3+ cations, this centrosymmetric compound undergoes a transition into an incommensurate antiferromagnetically ordered state below TN≃220 K. The magnetic structure is characterized by the propagation vector k=[0,β,0] with β≃0.14 and the P221211′(0β0)0s0s magnetic superspace symmetry. It comprises antiferromagnetic helixes propagating along the b axis. The magnetic moments lie in the ac plane and rotate about π(1+β)≃204.8-deg angle between the adjacent magnetic atoms along b. The spiral magnetic structure arises from the peculiar frustrated arrangement of exchange couplings in the ab plane. The antiferromagnetic coupling along the c axis cancels the possible electric polarization and prevents ferroelectricity in BiMnFe2O6.
Address
Corporate Author Thesis
Publisher Place of Publication (down) Editor
Language Wos 000291197400001 Publication Date 2011-06-03
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 12 Open Access
Notes Approved Most recent IF: 3.836; 2011 IF: 3.691
Call Number UA @ lucian @ c:irua:90080 Serial 3107
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Author Mordvinova, N.; Emelin, P.; Vinokurov, A.; Dorofeev, S.; Abakumov, A.; Kuznetsova, T.
Title Surface processes during purification of InP quantum dots Type A1 Journal article
Year 2014 Publication Beilstein journal of nanotechnology Abbreviated Journal Beilstein J Nanotech
Volume 5 Issue Pages 1220-1225
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Recently, a new simple and fast method for the synthesis of InP quantum dots by using phosphine as phosphorous precursor and myristic acid as surface stabilizer was reported. Purification after synthesis is necessary to obtain samples with good optical properties. Two methods of purification were compared and the surface processes which occur during purification were studied. Traditional precipitation with acetone is accompanied by a small increase in photoluminescence. It occurs that during the purification the hydrolysis of the indium precursor takes place, which leads to a better surface passivation. The electrophoretic purification technique does not increase luminescence efficiency but yields very pure quantum dots in only a few minutes. Additionally, the formation of In(OH)(3) during the low temperature synthesis was explained. Purification of quantum dots is a very significant part of post-synthetical treatment that determines the properties of the material. But this subject is not sufficiently discussed in the literature. The paper is devoted to the processes that occur at the surface of quantum dots during purification. A new method of purification, electrophoresis, is investigated and described in particular.
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Publisher Place of Publication (down) Editor
Language Wos 000339912400002 Publication Date 2014-08-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2190-4286; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.127 Times cited 5 Open Access
Notes Approved Most recent IF: 3.127; 2014 IF: 2.670
Call Number UA @ lucian @ c:irua:118748 Serial 3397
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Author Shpanchenko, R.V.; Tsirlin, A.A.; Hadermann, J.; Antipov, E.V.
Title Synthesis and crystal structure of new titanyl phosphate Sr2TiO(PO4)2 Type A1 Journal article
Year 2008 Publication Russian chemical bulletin Abbreviated Journal Russ Chem B+
Volume 57 Issue 3 Pages 552-556
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract New strontium titanyl phosphate Sr2TiO(PO4)2 (1) was synthesized and characterized by X-ray powder diffraction, electron diffraction, high-resolution electron microscopy, and band structure calculations. Titanyl phosphate 1 is isostructural with vanadyl phosphate Sr2VO(PO4)2 and has a layered structure. The titanium atoms are shifted from the centers of the TiO6 octahedra and form short (1.74 Å) titanyl bonds. The structure of 1 is an unusual example of the disordered orientation of the chains formed by TiO6 octahedra in complex titanium phosphates.
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Corporate Author Thesis
Publisher Place of Publication (down) Editor
Language Wos 000263566900015 Publication Date 2009-03-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1066-5285;1573-9171; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 0.529 Times cited 2 Open Access
Notes Approved Most recent IF: 0.529; 2008 IF: 0.469
Call Number UA @ lucian @ c:irua:73712 Serial 3423
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Author Tsirlin, A.A.; Abakumov, A.M.; Ritter, C.; Rosner, H.
Title (CuCl)LaTa2O\text{7} and quantum phase transition in the (CuX)LaM2O7 family (X=Cl, Br; M=Nb, Ta) Type A1 Journal article
Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 86 Issue 6 Pages 064440-12
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We apply neutron diffraction, high-resolution synchrotron x-ray diffraction, magnetization measurements, electronic structure calculations, and quantum Monte-Carlo simulations to unravel the structure and magnetism of (CuCl)LaTa2O7. Despite the pseudo-tetragonal crystallographic unit cell, this compound features an orthorhombic superstructure, similar to the Nb-containing (CuX)LaNb2O7 with X = Cl and Br. The spin lattice entails dimers formed by the antiferromagnetic fourth-neighbor coupling J(4), as well as a large number of nonequivalent interdimer couplings quantified by an effective exchange parameter J(eff). In (CuCl)LaTa2O7, the interdimer couplings are sufficiently strong to induce the long-range magnetic order with the Neel temperature T-N similar or equal to 7 K and the ordered magnetic moment of 0.53 mu(B), as measured with neutron diffraction. This magnetic behavior can be accounted for by J(eff)/J(4) similar or equal to 1.6 and J(4) similar or equal to 16 K. We further propose a general magnetic phase diagram for the (CuCl)LaNb2O7-type compounds, and explain the transition from the gapped spin-singlet (dimer) ground state in (CuCl)LaNb2O7 to the long-range antiferromagnetic order in (CuCl)LaTa2O7 and (CuBr)LaNb2O7 by an increase in the magnitude of the interdimer couplings J(eff)/J(4), with the (CuCl)LaM2O7 (M = Nb, Ta) compounds lying on different sides of the quantum critical point that separates the singlet and long-range-ordered magnetic ground states.
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Corporate Author Thesis
Publisher Place of Publication (down) Editor
Language Wos 000308127600006 Publication Date 2012-08-29
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 6 Open Access
Notes Approved Most recent IF: 3.836; 2012 IF: 3.767
Call Number UA @ lucian @ c:irua:101886 Serial 3526
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Author Morozov, V.A.; Arakcheeva, A.V.; Pattison, P.; Meert, K.W.; Smet, P.F.; Poelman, D.; Gauquelin, N.; Verbeeck, J.; Abakumov, A.M.; Hadermann, J.
Title KEu(MoO4)2 : polymorphism, structures, and luminescent properties Type A1 Journal article
Year 2015 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 27 Issue 27 Pages 5519-5530
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract In this paper, with the example of two different polymorphs of KEu(MoO4)2, the influence of the ordering of the A-cations on the luminescent properties in scheelite related compounds (A′,A″)n[(B′,B″)O4]m is investigated. The polymorphs were synthesized using a solid state method. The study confirmed the existence of only two polymorphic forms at annealing temperature range 9231203 K and ambient pressure: a low temperature anorthic α-phase and a monoclinic high temperature β-phase with an incommensurately modulated structure. The structures of both polymorphs were solved using transmission electron microscopy and refined from synchrotron powder X-ray diffraction data. The monoclinic β-KEu(MoO4)2 has a (3+1)-dimensional incommensurately modulated structure (superspace group I2/b(αβ0)00, a = 5.52645(4) Å, b = 5.28277(4) Å, c = 11.73797(8) Å, γ = 91.2189(4)o, q = 0.56821(2)a*0.12388(3)b*), whereas the anorthic α-phase is (3+1)-dimensional commensurately modulated (superspace group I1̅(αβγ)0, a = 5.58727(22) Å, b = 5.29188(18)Å, c = 11.7120(4) Å, α = 90.485(3)o, β = 88.074(3)o, γ = 91.0270(23)o, q = 1/2a* + 1/2c*). In both cases the modulation arises due to Eu/K cation ordering at the A site: the formation of a 2-dimensional Eu3+ network is characteristic for the α-phase, while a 3-dimensional Eu3+-framework is observed for the β-phase structure. The luminescent properties of KEu(MoO4)2 samples prepared under different annealing conditions were measured, and the relation between their optical properties and their structures is discussed.
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Corporate Author Thesis
Publisher Place of Publication (down) Editor
Language Wos 000360323700011 Publication Date 2015-07-29
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 26 Open Access
Notes 278510 Vortex; Fwo G039211n; G004413n ECASJO_; Approved Most recent IF: 9.466; 2015 IF: 8.354
Call Number c:irua:127244 Serial 3537
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Author Shumilin, A.V.; Baranov, V.V.; Kabanov, V.V.
Title Upper critical field in the model with finite-range interaction between electrons Type A1 Journal article
Year 2016 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 94 Issue 94 Pages 174506
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We develop a theory of the upper critical field in a BCS superconductor with a nonlocal interaction between electrons. We have shown that the nonlocal interaction is characterized by the parameter k(F)rho(0), where k(F) is the Fermi momentum and rho(0) is the radius of electron-electron interaction. The presence of the external magnetic field leads to the generation of additional components of the order parameter with different angular momenta. This effect leads to the enhancement of the upper critical field above the orbital limiting field. In addition the upward curvature in the temperature dependence of H-c2 (T) in the clean limit is predicted. The impurity scattering suppresses the effect in the dirty limit.
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Corporate Author Thesis
Publisher Place of Publication (down) Editor
Language Wos 000387884100005 Publication Date 2016-11-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9950;2469-9969; ISBN Additional Links UA library record; WoS full record
Impact Factor 3.836 Times cited Open Access
Notes ; ; Approved Most recent IF: 3.836
Call Number UA @ lucian @ c:irua:139166 Serial 4365
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Author Sankaran, K.J.; Hoang, D.Q.; Srinivasu, K.; Korneychuk, S.; Turner, S.; Drijkoningen, S.; Pobedinskas, P.; Verbeeck, J.; Leou, K.C.; Lin, I.N.; Haenen, K.
Title Type A1 Journal article
Year 2016 Publication Physica status solidi : A : applications and materials science Abbreviated Journal Phys Status Solidi A
Volume 213 Issue 10 Pages 2654-2661
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Utilization of Au and nanocrystalline diamond ( NCD) as interlayers noticeably modifies the microstructure and field electron emission ( FEE) properties of hexagonal boron nitride nanowalls ( hBNNWs) grown on Si substrates. The FEE properties of hBNNWs on Au could be turned on at a low turn-on field of 14.3V mu m(-1), attaining FEE current density of 2.58mAcm(-2) and life-time stability of 105 min. Transmission electron microscopy reveals that the Au-interlayer nucleates the hBN directly, preventing the formation of amorphous boron nitride ( aBN) in the interface, resulting in enhanced FEE properties. But Au forms as droplets on the Si substrate forming again aBN at the interface. Conversely, hBNNWs on NCD shows superior in life-time stability of 287 min although it possesses inferior FEE properties in terms of larger turn-on field and lower FEE current density as compared to that of hBNNWs-Au. The uniform and continuous NCD film on Si also circumvents the formation of aBN phases and allows hBN to grow directly on NCD. Incorporation of carbon in hBNNWs from the NCD-interlayer improves the conductivity of hBNNWs, which assists in transporting the electrons efficiently from NCD to hBNNWs that results in better field emission of electrons with high life-time stability. (C) 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
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Corporate Author Thesis
Publisher Place of Publication (down) Editor
Language Wos 000388321500017 Publication Date 2016-09-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1862-6300 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.775 Times cited 5 Open Access
Notes The authors like to thank the financial support of the Research Foundation Flanders (FWO) via Research Projects G.0456.12 and G.0044.13N, the Methusalem “NANO” network. K. J. Sankaran, P. Pobedinskas, and S. Turner are FWO Postdoctoral Fellows of the Research Foundations Flanders (FWO). Approved Most recent IF: 1.775
Call Number UA @ lucian @ c:irua:144644UA @ admin @ c:irua:144644 Serial 4655
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Author Sankaran, K.J.; Duc Quang Hoang; Korneychuk, S.; Kunuku, S.; Thomas, J.P.; Pobedinskas, P.; Drijkoningen, S.; Van Bael, M.K.; D'Haen, J.; Verbeeck, J.; Leou, K.-C.; Leung, K.T.; Lin, I.-N.; Haenen, K.
Title Hierarchical hexagonal boron nitride nanowall-diamond nanorod heterostructures with enhanced optoelectronic performance Type A1 Journal article
Year 2016 Publication RSC advances Abbreviated Journal Rsc Adv
Volume 6 Issue 93 Pages 90338-90346
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A superior field electron emission (FEE) source made from a hierarchical heterostructure, where two-dimensional hexagonal boron nitride (hBN) nanowalls were coated on one-dimensional diamond nanorods (DNRs), is fabricated using a simple and scalable method. FEE characteristics of hBN-DNR display a low turn-on field of 6.0 V mu m(-1), a high field enhancement factor of 5870 and a high life-time stability of 435 min. Such an enhancement in the FEE properties of hBN-DNR derives from the distinctive material combination, i.e., high aspect ratio of the heterostructure, good electron transport from the DNR to the hBN nanowalls and efficient field emission of electrons from the hBN nanowalls. The prospective application of these heterostructures is further evidenced by enhanced microplasma devices using hBN-DNR as a cathode, in which the threshold voltage was lowered to 350 V, affirming the role of hBN-DNR in the improvement of electron emission.
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Corporate Author Thesis
Publisher Place of Publication (down) Editor
Language Wos 000385451800044 Publication Date 2016-09-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2046-2069 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.108 Times cited 8 Open Access
Notes The authors like to thank the financial support of the Research Foundation Flanders (FWO) via Research Projects G.0456.12 and G.0044.13N, the Methusalem “NANO” network. KJ Sankaran, and P Pobedinskas are Postdoctoral Fellows of the Research Foundation-Flanders (FWO). Approved Most recent IF: 3.108
Call Number UA @ lucian @ c:irua:144757UA @ admin @ c:irua:144757 Serial 4662
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Author Li, L.; Liao, Z.; Gauquelin, N.; Minh Duc Nguyen; Hueting, R.J.E.; Gravesteijn, D.J.; Lobato, I.; Houwman, E.P.; Lazar, S.; Verbeeck, J.; Koster, G.; Rijnders, G.
Title Epitaxial stress-free growth of high crystallinity ferroelectric PbZr0.52Ti0.48O3 on GaN/AlGaN/Si(111) substrate Type A1 Journal article
Year 2018 Publication Advanced Materials Interfaces Abbreviated Journal Adv Mater Interfaces
Volume 5 Issue 2 Pages 1700921
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract <script type='text/javascript'>document.write(unpmarked('Due to its physical properties gallium-nitride (GaN) is gaining a lot of attention as an emerging semiconductor material in the field of high-power and high-frequency electronics applications. Therefore, the improvement in the performance and/or perhaps even extension in functionality of GaN based devices would be highly desirable. The integration of ferroelectric materials such as lead-zirconate-titanate (PbZrxTi1-xO3) with GaN has a strong potential to offer such an improvement. However, the large lattice mismatch between PZT and GaN makes the epitaxial growth of Pb(Zr1-xTix)O-3 on GaN a formidable challenge. This work discusses a novel strain relaxation mechanism observed when MgO is used as a buffer layer, with thicknesses down to a single unit cell, inducing epitaxial growth of high crystallinity Pb(Zr0.52Ti0.48)O-3 (PZT) thin films. The epitaxial PZT films exhibit good ferroelectric properties, showing great promise for future GaN device applications.'));
Address
Corporate Author Thesis
Publisher Place of Publication (down) Editor
Language Wos 000423173800005 Publication Date 2017-11-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2196-7350 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.279 Times cited 15 Open Access Not_Open_Access
Notes ; L.L., Z.L.L., and N.G. contributed equally to this work. L.L. acknowledges financial support from Nano Next NL (Grant no. 7B 04). The authors acknowledge NXP for providing the GaN/AlGaN/Si (111) wafer. N.G. acknowledges funding from the Geconcentreerde Onderzoekacties (GOA) project “Solarpaint” of the University of Antwerp and J.V. acknowledges funding from the Research Foundation Flanders (FWO, Belgium) project 42/FA070100/6088 “nieuwe eigenschappen in complexe Oxides.” N.G. acknowledges the EUROTAPES project (FP7-NMP.2011.2.2-1 Grant no. 280432) which partly funded this study. ; Approved Most recent IF: 4.279
Call Number UA @ lucian @ c:irua:148427UA @ admin @ c:irua:148427 Serial 4872
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Author Fedoseeva, Y.V.; Orekhov, A.S.; Chekhova, G.N.; Koroteev, V.O.; Kanygin, M.A.; Seovskiy, B.V.; Chuvilin, A.; Pontiroli, D.; Ricco, M.; Bulusheva, L.G.; Okotrub, A.V.
Title Single-walled carbon nanotube reactor for redox transformation of mercury dichloride Type A1 Journal article
Year 2017 Publication ACS nano Abbreviated Journal Acs Nano
Volume 11 Issue 9 Pages 8643-8649
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract <script type='text/javascript'>document.write(unpmarked('Single-walled carbon nanotubes (SWCNTs) possessing a confined inner space protected by chemically resistant shells are promising for delivery, storage, and desorption of various compounds, as well as carrying out specific reactions. Here, we show that SWCNTs interact with molten mercury dichloride (HgCl2) and guide its transformation into dimercury dichloride (Hg2Cl2) in the cavity. The chemical state of host SWCNTs remains almost unchanged except for a small p-doping from the guest Hg2Cl2 nanocrystals. The density functional theory calculations reveal that the encapsulated HgCl2 molecules become negatively charged and start interacting via chlorine bridges when local concentration increases. This reduces the bonding strength in HgCl2, which facilitates removal of chlorine, finally leading to formation of Hg2Cl2 species. The present work demonstrates that SWCNTs not only serve as a template for growing nanocrystals but also behave as an electron-transfer catalyst in the spatially confined redox reaction by donation of electron density for temporary use by the guests.'));
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Publisher Place of Publication (down) Editor
Language Wos 000411918200012 Publication Date 2017-08-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1936-0851 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 13.942 Times cited 11 Open Access Not_Open_Access
Notes ; Collaboration between partner institutions was partially supported by European FP7 IRSES project 295180. We are grateful to the bilateral Program “Russian-German Laboratory at BESSY II” for the assistance in XPS and NEXAFS measurements. We acknowledge C. Tollan for proofreading the manuscript. We are grateful to Dr. Y.V. Shubin for XRD measurements of graphite with HgCl<INF>2</ INF>. ; Approved Most recent IF: 13.942
Call Number UA @ lucian @ c:irua:146770 Serial 4895
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Author Fridman, A.; Lin, A.; Miller, V.; Bekeschus, S.; Wende, K.; Weltmann, K.-D.
Title The plasma treatment unit : an attempt to standardize cold plasma treatment for defined biological effects Type A1 Journal article
Year 2018 Publication Plasma medicine Abbreviated Journal
Volume 8 Issue 2 Pages 195-201
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Plasma bioscience and medicine are both rapidly growing fields. Their aim is to utilize cold physical plasmas for desired biological outcomes in medicine, biotechnology, agriculture, and general hygienic purposes. Great success has been achieved in many applications with individually designed plasma sources and plasma parameters. Although lab and application-specific tuning of plasmas is a great advantage of this technology, standardized units to define plasma treatments are required to facilitate comparison of the effects found by different researchers who do not use the same plasma sources. By drawing conclusions from over a century of plasma biomedical research, we propose that all researchers adopt the use of a standardized value, the plasma treatment unit (PTU), to describe the biological effects of different cold plasma sources and treatment regimens. It quantifies a key plasma effector in biological systems as an indicator and may provide the foundation for an analogous and clinically relevant unit in the future.
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Publisher Place of Publication (down) Editor
Language Wos Publication Date 2018-06-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record
Impact Factor Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:155652 Serial 5123
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Author Lin, A.G.; Xiang, B.; Merlino, D.J.; Baybutt, T.R.; Sahu, J.; Fridman, A.; Snook, A.E.; Miller, V.
Title Non-thermal plasma induces immunogenic cell death in vivo in murine CT26 colorectal tumors Type A1 Journal article
Year 2018 Publication Oncoimmunology Abbreviated Journal
Volume 7 Issue 9 Pages e1484978
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Immunogenic cell death is characterized by the emission of danger signals that facilitate activation of an adaptive immune response against dead-cell antigens. In the case of cancer therapy, tumor cells undergoing immunogenic death promote cancer-specific immunity. Identification, characterization, and optimization of stimuli that induce immunogenic cancer cell death has tremendous potential to improve the outcomes of cancer therapy. In this study, we show that non-thermal, atmospheric pressure plasma can be operated to induce immunogenic cell death in an animal model of colorectal cancer. In vitro, plasma treatment of CT26 colorectal cancer cells induced the release of classic danger signals. Treated cells were used to create a whole-cell vaccine which elicited protective immunity in the CT26 tumor mouse model. Moreover, plasma treatment of subcutaneous tumors elicited emission of danger signals and recruitment of antigen presenting cells into tumors. An increase in T cell responses targeting the colorectal cancer-specific antigen guanylyl cyclase C (GUCY2C) were also observed. This study provides the first evidence that non-thermal plasma is a bone fide inducer of immunogenic cell death and highlights its potential for clinical translation for cancer immunotherapy.
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Publisher Place of Publication (down) Editor
Language Wos 000443993100030 Publication Date 2018-06-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2162-4011; 2162-402x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 28 Open Access Not_Open_Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:155651 Serial 5119
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Author Hu, L.; Amini, M.N.; Wu, Y.; Jin, Z.; Yuan, J.; Lin, R.; Wu, J.; Dai, Y.; He, H.; Lu, Y.; Lu, J.; Ye, Z.; Han, S.-T.; Ye, J.; Partoens, B.; Zeng, Y.-J.; Ruan, S.
Title Charge transfer doping modulated raman scattering and enhanced stability of black phosphorus quantum dots on a ZnO nanorod Type A1 Journal article
Year 2018 Publication Advanced Optical Materials Abbreviated Journal Adv Opt Mater
Volume 6 Issue 15 Pages 1800440
Keywords A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Black phosphorus (BP) has recently triggered an unprecedented interest in the 2D community. However, many of its unique properties are not exploited and the well-known environmental vulnerability is not conquered. Herein, a type-I mixed-dimensional (0D-1D) van der Waals heterojunction is developed, where three-atomic-layer BP quantum dots (QDs) are assembled on a single ZnO nanorod (NR). By adjusting the indium (In) content in ZnO NRs, the degree and even the direction of surface charge transfer doping within the heterojunction can be tuned, which result in selective Raman scattering enhancements between ZnO and BP. The maximal enhancement factor is determined as 4340 for BP QDs with sub-ppm level. Furthermore, an unexpected long-term ambient stability (more than six months) of BP QDs is revealed, which is ascribed to the electron doping from ZnO:In NRs. The first demonstration of selective Raman enhancements between two inorganic semiconductors as well as the improved stability of BP shed light on this emerging 2D material.
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Publisher Place of Publication (down) Editor
Language Wos 000440815200023 Publication Date 2018-05-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2195-1071 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.875 Times cited 37 Open Access Not_Open_Access
Notes ; L. Hu and M. N. Amini contributed equally to this work. This work was supported by the National Natural Science Foundation of China under Grant Nos. 51502178, 81571763 and 81622026, the Shenzhen Science and Technology Project under Grant Nos. JCYJ20150324141711644, JCYJ20170412105400428, KQJSCX20170727101208249 and JCYJ20170302153853962. Parts of the computational calculations were carried out using the HPC infrastructure at University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center VSC, supported financially by the FWO-Vlaanderen and the Flemish Government (EWI Department). L. H. acknowledges the PhD Start-up Fund of Natural Science Foundation of Guangdong Province under Grand No. 2017A030310072. J. Y. acknowledges the funding of Shanghai Jiao Tong University (Nos. YG2016MS51 and YG2017MS54). ; Approved Most recent IF: 6.875
Call Number UA @ lucian @ c:irua:153112UA @ admin @ c:irua:153112 Serial 5082
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Author Gan, Y.; Christensen, D.V.; Zhang, Y.; Zhang, H.; Krishnan, D.; Zhong, Z.; Niu, W.; Carrad, D.J.; Norrman, K.; von Soosten, M.; Jespersen, T.S.; Shen, B.; Gauquelin, N.; Verbeeck, J.; Sun, J.; Pryds, N.; Chen, Y.
Title Diluted oxide interfaces with tunable ground states Type A1 Journal article
Year 2019 Publication Advanced materials Abbreviated Journal Adv Mater
Volume 31 Issue 10 Pages 1805970
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The metallic interface between two oxide insulators, such as LaAlO3/SrTiO3 (LAO/STO), provides new opportunities for electronics and spintronics. However, due to the presence of multiple orbital populations, tailoring the interfacial properties such as the ground state and metal-insulator transitions remains challenging. Here, an unforeseen tunability of the phase diagram of LAO/STO is reported by alloying LAO with a ferromagnetic LaMnO3 insulator without forming lattice disorder and at the same time without changing the polarity of the system. By increasing the Mn-doping level, x, of LaAl1-xMnxO3/STO (0 <= x <= 1), the interface undergoes a Lifshitz transition at x = 0.225 across a critical carrier density of n(c) = 2.8 x 10(13) cm(-2), where a peak T-SC approximate to 255 mK of superconducting transition temperature is observed. Moreover, the LaAl1-xMnxO3 turns ferromagnetic at x >= 0.25. Remarkably, at x = 0.3, where the metallic interface is populated by only d(xy) electrons and just before it becomes insulating, a same device with both signatures of superconductivity and clear anomalous Hall effect (7.6 x 10(12) cm(-2) < n(s) <= 1.1 x 10(13) cm(-2)) is achieved reproducibly. This provides a unique and effective way to tailor oxide interfaces for designing on-demand electronic and spintronic devices.
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Publisher Place of Publication (down) Editor
Language Wos 000460329300004 Publication Date 2019-01-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0935-9648 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 19.791 Times cited 31 Open Access Not_Open_Access
Notes ; The authors thank the technical help from J. Geyti. J.R.S. acknowledges the support of the National Basic Research of China (2016YFA0300701, 2018YFA0305704), the National Natural Science Foundation of China (11520101002), and the Key Program of the Chinese Academy of Sciences. N.G., D.K., and J.V. acknowledge funding from the Geconcentreerde Onderzoekacties (GOA) project “Solarpaint” of the University of Antwerp, Belgium. ; Approved Most recent IF: 19.791
Call Number UA @ admin @ c:irua:158553 Serial 5245
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Author O'Donnell, D.; Hassan, S.; Du, Y.; Gauquelin, N.; Krishnan, D.; Verbeeck, J.; Fan, R.; Steadman, P.; Bencok, P.; Dobrynin, A.N.
Title Etching induced formation of interfacial FeMn in IrMn/CoFe bilayers Type A1 Journal article
Year 2019 Publication Journal of physics: D: applied physics Abbreviated Journal J Phys D Appl Phys
Volume 52 Issue 16 Pages 165002
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The effect of ion etching on exchange bias in IrMn3/Co70Fe30 bilayers is investigated. In spite of the reduction of saturation magnetization caused by the embedding of Tr from the capping layer into the Co70Fe30 layer during the etching process, the exchange bias in samples with the same thickness of the Co70Fe30 layer is reducing in proportion to the etching power. X-ray magnetic circular dichroism measurements revealed the emergence of an uncompensated Mn magnetization after etching, which is antiferromagnetically coupled to the ferromagnetic layer. This suggests etching induced formation of small interfacial FeMn regions which leads to the decrease of effective exchange coupling between ferromagnetic and antiferromagnetic layers.
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Publisher Place of Publication (down) Editor
Language Wos 000458524800001 Publication Date 2019-01-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-3727 ISBN Additional Links UA library record; WoS full record
Impact Factor 2.588 Times cited Open Access OpenAccess
Notes ; This work was supported by Seagate Technology (Ireland). Beamline I10, Diamond Light Source, is acknowledged for provided beamtime. ; Approved Most recent IF: 2.588
Call Number UA @ admin @ c:irua:157458 Serial 5247
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Author Behera, B.C.; Jana, S.; Bhat, S.G.; Gauquelin, N.; Tripathy, G.; Kumar, P.S.A.; Samal, D.
Title Evidence for exchange bias coupling at the perovskite/brownmillerite interface in spontaneously stabilized SrCoO3-\delta/SrCoO2.5 bilayers Type A1 Journal article
Year 2019 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 99 Issue 2 Pages 024425
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Interface effect in complex oxide thin-film heterostructures lies at the vanguard of current research to design technologically relevant functionality and explore emergent physical phenomena. While most of the previous works focus on the perovskite/perovskite heterostructures, the study of perovskite/brownmillerite interfaces remains in its infancy. Here, we investigate spontaneously stabilized perovskite-ferromagnet (SrCoO3-delta)/brownmillerite-antiferromagnet (SrCoO2.5) bilayer with T-N > T-C and discover an unconventional interfacial magnetic exchange bias effect. From magnetometry investigations, it is rationalized that the observed effect stems from the interfacial ferromagnet/antiferromagnet coupling. The possibility for coupled ferromagnet/spin-glass interface engendering such effect is ruled out. Strikingly, a finite coercive field persists in the paramagnetic state of SrCoO3-delta,whereas the exchange bias field vanishes at T-C . We conjecture the observed effect to be due to the effective external quenched staggered field provided by the antiferromagnetic layer for the ferromagnetic spins at the interface. Our results not only unveil a paradigm to tailor the interfacial magnetic properties in oxide heterostructures without altering the cations at the interface, but also provide a purview to delve into the fundamental aspects of exchange bias in such unusual systems, paving a big step forward in thin-film magnetism.
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Publisher Place of Publication (down) Editor
Language Wos 000456481900003 Publication Date 2019-01-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 2 Open Access OpenAccess
Notes ; We are grateful to Sachin Sarangi for his superb technical support during magnetic measurements. We thank Gopal Pradhan for fruitful discussion. We thank Zhicheng Zhong for reading the manuscript and for suggestions. We thank T. Som for extending laboratory facility. D.S. and B.C.B. acknowledge the financial support from Max-Planck Society through Max Planck Partner Group. S.G.B. acknowledges the INSPIRE Faculty Fellowship Programme (DSTO1899) for the financial support. ; Approved Most recent IF: 3.836
Call Number UA @ admin @ c:irua:157562 Serial 5248
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Author Tonkikh, A.A.; Tsebro, V.I.; Obraztsova, E.A.; Rybkovskiy, D.V.; Orekhov, A.S.; Kondrashov, I.I.; Kauppinen, E.I.; Chuvilin, A.L.; Obraztsova, E.D.
Title Films of filled single-wall carbon nanotubes as a new material for high-performance air-sustainable transparent conductive electrodes operating in a wide spectral range Type A1 Journal article
Year 2019 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 11 Issue 14 Pages 6755-6765
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract In this paper we show the advantages of transparent high conductive films based on filled single-wall carbon nanotubes. The nanotubes with internal channels filled with acceptor molecules (copper chloride or iodine) form networks demonstrating significantly improved characteristics. Due to the charge transfer between the nanotubes and filler, the doped-nanotube films exhibit a drop in electrical sheet resistance of an order of magnitude together with a noticeable increase of film transparency in the visible and near-infrared spectral range. The thermoelectric power measurements show a significant improvement of air-stability of the nanotube network in the course of the filling procedure. For the nanotube films with an initial transparency of 87% at 514 nm and electrical sheet resistance of 862 Ohm sq(-1) we observed an improvement of transparency up to 91% and a decrease of sheet resistance down to 98 Ohm sq(-1). The combination of the nanotube synthesis technique and molecules for encapsulation has been optimized for applications in optoelectronics.
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Publisher Place of Publication (down) Editor
Language Wos 000464454400024 Publication Date 2019-03-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2040-3364 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.367 Times cited 2 Open Access Not_Open_Access: Available from 06.09.2019
Notes ; The work was supported by the RFBR project 18-29-19113-mk, grant no. 311533 of Academy of Finland, Russian Federation President Program for young scientist MK-3140.2018.2. Also, the reported study was funded by RFBR and Moscow city Government according to the research project no. 19-32-70004. TEM measurements were performed with financial support from the Ministry of Science and Higher Education of the Russian Federation within the state assignment for the Federal Scientific Research Centre “Crystallography and Photonics” of the Russian Academy of Sciences. ; Approved Most recent IF: 7.367
Call Number UA @ admin @ c:irua:159339 Serial 5249
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Author Das, S.; Rata, A.D.; Maznichenko, I., V; Agrestini, I.S.; Pippel, E.; Gauquelin, N.; Verbeeck, J.; Chen, K.; Valvidares, S.M.; Vasili, H.B.; Herrero-Martin, J.; Pellegrin, E.; Nenkov, K.; Herklotz, A.; Ernst, A.; Mertig, I.; Hu, Z.; Doerr, K.
Title Low-field switching of noncollinear spin texture at La0.7Sr0.3MnO3-SrRuO3interfaces Type A1 Journal article
Year 2019 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 99 Issue 2 Pages 024416
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Interfaces of ferroic oxides can show complex magnetic textures which have strong impact on spintronics devices. This has been demonstrated recently for interfaces with insulating antiferromagnets such as BiFeO3. Here, noncollinear spin textures which can be switched in very low magnetic field are reported for conducting ferromagnetic bilayers of La0.7Sr0.3MnO3-SrRuO3 (LSMO-SRO). The magnetic order and switching are fundamentally different for bilayers coherently grown in reversed stacking sequence. The SRO top layer forms a persistent exchange spring which is antiferromagnetically coupled to LSMO and drives switching in low fields of a few milliteslas. Density functional theory reveals the crucial impact of the interface termination on the strength of Mn-Ru exchange coupling across the interface. The observation of an exchange spring agrees with ultrastrong coupling for the MnO2/SrO termination. Our results demonstrate low-field switching of noncollinear spin textures at an interface between conducting oxides, opening a pathway for manipulating and utilizing electron transport phenomena in controlled spin textures at oxide interfaces.
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Publisher Place of Publication (down) Editor
Language Wos 000455821400005 Publication Date 2019-01-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 19 Open Access OpenAccess
Notes ; The research in Halle was supported by Deutsche Forschungsgemeinschaft (DFG), SFB 762 Functional Oxide Interfaces (Projects No. A9 and No. B1). K.C. benefited from support of the DFG (Project 600575). Discussions with M. Trassin, M. Ziese, H. M. Christen, E.-J. Guo, F. Grcondciel, M. Bibes, and H. N. Lee are gratefully acknowledged. N. G. and J. V. acknowledge funding under the GOA project “Solarpaint” of the University of Antwerp. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. ; Approved Most recent IF: 3.836
Call Number UA @ admin @ c:irua:156717 Serial 5255
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Author Sankaran, K.J.; Deshmukh, S.; Korneychuk, S.; Yeh, C.-J.; Thomas, J.P.; Drijkoningen, S.; Pobedinskas, P.; Van Bael, M.K.; Verbeeck, J.; Leou, K.-C.; Leung, K.-T.; Roy, S.S.; Lin, I.-N.; Haenen, K.
Title Fabrication, microstructure, and enhanced thermionic electron emission properties of vertically aligned nitrogen-doped nanocrystalline diamond nanorods Type A1 Journal article
Year 2018 Publication MRS communications Abbreviated Journal Mrs Commun
Volume 8 Issue 3 Pages 1311-1320
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Vertically aligned nitrogen-doped nanocrystalline diamond nanorods are fabricated from nitrogen-doped nanocrystalline diamond films using reactive ion etching in oxygen plasma. These nanorods show enhanced thermionic electron emission (TEE) characteristics, viz.. a high current density of 12.0 mA/cm(2) and a work function value of 4.5 eV with an applied voltage of 3 Vat 923 K. The enhanced TEE characteristics of these nanorods are ascribed to the induction of nanographitic phases at the grain boundaries and the field penetration effect through the local field enhancement from nanorods owing to a high aspect ratio and an excellent field enhancement factor.
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Language Wos 000448887900089 Publication Date 2018-08-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2159-6859; 2159-6867 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.01 Times cited 1 Open Access
Notes The authors thank the financial support of the Research Foundation Flanders (FWO) via Research Grant 12I8416N and Research Project 1519817N, and the Methusalem “NANO” network. The Hercules Foundation Flanders is acknowledged for financial support of the Raman equipment. The Qu-Ant-EM microscope used for the TEM experiments was partly funded by the Hercules fund from the Flemish Government. S.K. and J.V. acknowledge funding from GOA project “Solarpaint” of the University of Antwerp. K.J. Sankaran and P. Pobedinskas are Postdoctoral Fellows of FWO. Approved Most recent IF: 3.01
Call Number UA @ admin @ c:irua:155521 Serial 5364
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Author Conings, B.; Babayigit, A.; Klug, M.; Bai, S.; Gauquelin, N.; Sakai, N.; Wang, J.T.-W.; Verbeeck, J.; Boyen, H.-G.; Snaith, H.
Title Getting rid of anti-solvents: gas quenching for high performance perovskite solar cells Type P1 Proceeding
Year 2018 Publication 2018 Ieee 7th World Conference On Photovoltaic Energy Conversion (wcpec)(a Joint Conference Of 45th Ieee Pvsc, 28th Pvsec & 34th Eu Pvsec) Abbreviated Journal
Volume Issue Pages
Keywords P1 Proceeding; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract As the field of perovskite optoelectronics developed, a plethora of strategies has arisen to control their electronic and morphological characteristics for the purpose of producing high efficiency devices. Unfortunately, despite this wealth of deposition approaches, the community experiences a great deal of irreproducibility between different laboratories, batches and preparation methods. Aiming to address this issue, we developed a simple deposition method based on gas quenching that yields smooth films for a wide range of perovskite compositions, in single, double, triple and quadruple cation varieties, and produces planar heterojunction devices with competitive efficiencies, so far up to 20%.
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Language Wos 000469200401163 Publication Date 2018-12-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 978-1-5386-8529-7 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:160468 Serial 5365
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Author Deshmukh, S.; Sankaran, K.J.; Korneychuk, S.; Verbeeck, J.; Mclaughlin, J.; Haenen, K.; Roy, S.S.
Title Nanostructured nitrogen doped diamond for the detection of toxic metal ions Type A1 Journal article
Year 2018 Publication Electrochimica acta Abbreviated Journal Electrochim Acta
Volume 283 Issue 283 Pages 1871-1878
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract This work demonstrates the applicability of one-dimensional nitrogen-doped diamond nanorods (N-DNRs) for the simultaneous electrochemical (EC) detection of Pb2+ and Cd2+ ions in an electrolyte solution. Well separated voltammetric peaks are observed for Pb2+ and Cd2+ ions using N-DNRs as a working electrode in square wave anodic stripping voltammetry measurements. Moreover, the cyclic voltammetry response of N-DNR electrodes towards the Fe(CN)(6)(/4-)/Fe(CN)(6)(/3-) redox reaction is better as compared to undoped DNR electrodes. This enhancement of EC performance in N-DNR electrodes is accounted by the increased amount of sp(2) bonded nanographitic phases, enhancing the electrical conductivity at the grain boundary (GB) regions. These findings are supported by transmission electron microscopy and electron energy loss spectroscopy studies. Consequently, the GB defect induced N-DNRs exhibit better adsorption of metal ions, which makes such samples promising candidates for next generation EC sensing devices. (C) 2018 Elsevier Ltd. All rights reserved.
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Publisher Place of Publication (down) Editor
Language Wos 000441077900203 Publication Date 2018-07-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4686 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.798 Times cited 22 Open Access
Notes Sujit Deshmukh indebted to Shiv Nadar University for providing Ph. D. scholarship. The FEI Quanta SEM and Qu-Ant-EM microscope used for the TEM experiments was partly funded by the Hercules fund from the Flemish Government. S. K. and J. V. acknowledge funding from GOA project “Solarpaint” of the University of Antwerp. Kamatchi Jothiramalingam Sankaran is a Postdoctoral Fellow of the Research Foundation-Flanders (FWO). Prof. Ken Haenen acknowledges the Methusalem “NANO” network for financial support. Approved Most recent IF: 4.798
Call Number UA @ admin @ c:irua:153072 Serial 5366
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Author Liao, Z.; Gauquelin, N.; Green, R.J.; Macke, S.; Gonnissen, J.; Thomas, S.; Zhong, Z.; Li, L.; Si, L.; Van Aert, S.; Hansmann, P.; Held, K.; Xia, J.; Verbeeck, J.; Van Tendeloo, G.; Sawatzky, G.A.; Koster, G.; Huijben, M.; Rijnders, G.
Title Thickness dependent properties in oxide heterostructures driven by structurally induced metal-oxygen hybridization variations Type A1 Journal article
Year 2017 Publication Advanced functional materials Abbreviated Journal Adv Funct Mater
Volume 27 Issue 17 Pages 1606717
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Thickness-driven electronic phase transitions are broadly observed in different types of functional perovskite heterostructures. However, uncertainty remains whether these effects are solely due to spatial confinement, broken symmetry, or rather to a change of structure with varying film thickness. Here, this study presents direct evidence for the relaxation of oxygen-2p and Mn-3d orbital (p-d) hybridization coupled to the layer-dependent octahedral tilts within a La2/3Sr1/3MnO3 film driven by interfacial octahedral coupling. An enhanced Curie temperature is achieved by reducing the octahedral tilting via interface structure engineering. Atomically resolved lattice, electronic, and magnetic structures together with X-ray absorption spectroscopy demonstrate the central role of thickness-dependent p-d hybridization in the widely observed dimensionality effects present in correlated oxide heterostructures.
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Publisher Place of Publication (down) Editor
Language Wos 000400449200011 Publication Date 2017-03-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1616-301x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.124 Times cited 55 Open Access
Notes M.H., G.K., and G.R. acknowledge funding from DESCO program of the Dutch Foundation for Fundamental Research on Matter (FOM) with financial support from the Netherlands Organization for Scientific Research (NWO). This work was funded by the European Union Council under the 7th Framework Program (FP7) Grant No. NMP3-LA-2010-246102 IFOX. J.V. and S.V.A. acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (Grant Nos. G.0044.13N, G.0374.13N, G.0368.15N, and G.0369.15N). The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. N.G. acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant No. 278510 VORTEX. N.G., J.G., S.V.A., and J.V. acknowledge financial support from the European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure Initiative (Reference No. 312483-ESTEEM2). The Canadian work was supported by NSERC and the Max Planck-UBC Centre for Quantum Materials. Some experiments for this work were performed at the Canadian Light Source, which was funded by the Canada Foundation for Innovation, NSERC, the National Research Council of Canada, the Canadian Institutes of Health Research, the Government of Saskatchewan, Western Economic Diversification Canada, and the University of Saskatchewan. Approved Most recent IF: 12.124
Call Number UA @ admin @ c:irua:152640 Serial 5367
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Author Ramaneti, R.; Sankaran, K.J.; Korneychuk, S.; Yeh, C.J.; Degutis, G.; Leou, K.C.; Verbeeck, J.; Van Bael, M.K.; Lin, I.N.; Haenen, K.
Title Vertically aligned diamond-graphite hybrid nanorod arrays with superior field electron emission properties Type A1 Journal article
Year 2017 Publication APL materials Abbreviated Journal Apl Mater
Volume 5 Issue 6 Pages 066102
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract A “patterned-seeding technique” in combination with a “nanodiamond masked reactive ion etching process” is demonstrated for fabricating vertically aligned diamond-graphite hybrid (DGH) nanorod arrays. The DGH nanorod arrays possess superior field electron emission (FEE) behavior with a low turn-on field, long lifetime stability, and large field enhancement factor. Such an enhanced FEE is attributed to the nanocomposite nature of theDGHnanorods, which contain sp(2)-graphitic phases in the boundaries of nano-sized diamond grains. The simplicity in the nanorod fabrication process renders the DGH nanorods of greater potential for the applications as cathodes in field emission displays and microplasma display devices. (C) 2017 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license.
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Language Wos 000404623000002 Publication Date 2017-06-08
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ISSN 2166-532x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.335 Times cited 16 Open Access
Notes The authors would like to thank the Methusalem “NANO” network for financial support and Mr. B. Ruttens and Professor Jan D'Haen for technical and experimental assistance. K.J. Sankaran is a Postdoctoral Fellow of the Research Foundation-Flanders (FWO). Approved Most recent IF: 4.335
Call Number UA @ admin @ c:irua:152633 Serial 5369
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Author Amato, S.R.; Burnstock, A.; Cross, M.; Janssens, K.; Rosi, F.; Cartechini, L.; Fontana, R.; Dal Fovo, A.; Paolantoni, M.; Grazia, C.; Romani, A.; Michelin, A.; Andraud, C.; Tournie, A.; Dik, J.
Title Interpreting technical evidence from spectral imaging of paintings by Edouard Manet in the Courtauld Gallery Type A1 Journal article
Year 2019 Publication X-ray spectrometry T2 – MA-XRF Workshop on Developments and Applications of Macro-XRF in, Conservation, Art, and Archeology, SEP 24-25, 2017, Trieste, ITALY Abbreviated Journal X-Ray Spectrom
Volume 48 Issue 4 Pages 282-292
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract The paintings by edouard Manet in The Courtauld Gallery Dejeuner sur l'herbe (1863-68), Marguerite de Conflans en Toilette de Bal (1870-1880), Banks of the Seine at Argenteuil (1874), and A Bar at the Folies-Bergere (1882) were investigated for the first time using a range of non-invasive in situ analyses. The aims of the study were to investigate the painting techniques and materials used for this group of works and to critically evaluate the technical evidence derived from the integrated use of imaging techniques and portable spectroscopic methods in this context. The paintings were investigated by means of macro X-ray fluorescence (MA-XRF), reflection spectral imaging, portable UV-Vis-NIR spectroscopy, portable Raman spectroscopy, and reflection FTIR. MA-XRF and reflection spectral imaging allowed visualising elements in the compositions that were not visible using traditional methods of technical study. For example, MA-XRF analysis of Dejeuner sur l'herbe revealed elements of the development of the composition that provided new evidence to consider its relationship to other versions of the composition. The study also highlighted questions about the interpretation of elemental distribution maps and spectral images that did not correspond to the reworking visible in X-radiographs. For example, in A Bar at the Folies-Bergere Manet made numerous changes during painting, which were not clearly visualised with any of the techniques used. The research has wider implications for the study of Impressionist paintings, as the results will support technical studies of works by other artists of the period who used similar materials and painting methods.
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Language Wos 000472210700005 Publication Date 2018-01-23
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ISSN 0049-8246 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.298 Times cited Open Access
Notes ; Financial support by the Access to Research Infrastructures activity in the Horizon 2020 Programme of the EU (IPERION CH Grant agreement 654028) is gratefully acknowledged. ; Approved Most recent IF: 1.298
Call Number UA @ admin @ c:irua:161296 Serial 5670
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Author Miliani, C.; Monico, L.; Melo, M.J.; Fantacci, S.; Angelin, E.M.; Romani, A.; Janssens, K.
Title Photochemistry of Artists' Dyes and Pigments : towards better understanding and prevention of colour change in works of art Type A1 Journal article
Year 2018 Publication Angewandte Chemie: international edition in English Abbreviated Journal Angew Chem Int Edit
Volume 57 Issue 25 Pages 7324-7334
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract The absorption of light gives a pigment its colour and its reason for being, but it also creates excited states, that is, new molecules with an energy excess that can be dissipated through degradation pathways. Photodegradation processes provoke long-term, cumulative and irreversible colour changes (fading, darkening, blanching) of which the prediction and prevention are challenging tasks. Of all the environmental risks that affect heritage materials, light exposure is the only one that cannot be controlled without any impact on the optimal display of the exhibit. Light-induced alterations are not only associated with the pigment itself but also with its interactions with support/binder and, in turn, are further complicated by the nature of the environmental conditions. In this Minireview we investigate how chemistry, encompassing multi-scale analytical investigations of works of art, computational modelling and physical and chemical studies contributes to improve our prediction of artwork appearance before degradation and to establish effective preventive conservation strategies.
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Language Wos 000434949200006 Publication Date 2018-04-26
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ISSN 1433-7851; 0570-0833 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 11.994 Times cited 10 Open Access
Notes ; We acknowledge: ACS and APS for the permission to adapt Figure 1c,d; RSC to adapt Figures 1e, 3c,d and 4a; Wiley and IUCr to adapt Figures 3b and 4b-d; for the detail of a Andean textile in Figure 5, Museum of Fine Arts, Boston, USA; for the illuminated initial in Figure 6, Torre do Tombo (ANTT). Financial support from the H2020 project IPERION-CH (GA. 654028) is gratefully acknowledged. ; Approved Most recent IF: 11.994
Call Number UA @ admin @ c:irua:153184 Serial 5769
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Author Ghanian, M.; Ghoochani, O.M.; Kitterlin, M.; Jahangiry, S.; Zarafshani, K.; Van Passel, S.; Azadi, H.
Title Attitudes of agricultural experts toward genetically modified crops : a case study in Southwest Iran Type A1 Journal article
Year 2016 Publication Science And Engineering Ethics Abbreviated Journal Sci Eng Ethics
Volume 22 Issue 2 Pages 509-524
Keywords A1 Journal article; Economics; Engineering Management (ENM)
Abstract The production of genetically modified (GM) crops is growing around the world, and with it possible opportunities to combat food insecurity and hunger, as well as solutions to current problems facing conventional agriculture. In this regard the use of GMOs in food and agricultural applications has increased greatly over the past decade. However, the development of GM crops has been a matter of considerable interest and worldwide public controversy. This, in addition to skepticism, has stifled the use of this practice on a large scale in many areas, including Iran. It stands to reason that a greater understanding of this practice could be formed after a review of the existing expert opinions surrounding GM crops. Therefore, the purpose of this study was to analyze the predictors that influence agricultural experts attitudes toward the development of and policies related to GM crops. Using a descriptive correlational research method, questionnaire data was collected from 65 experts from the Agricultural Organization in the Gotvand district in Southwest Iran. Results indicated that agricultural experts were aware of the environmental benefits and possible risks associated with GM crops. The majority of participants agreed that GM crops could improve food security and accelerate rural development, and were proponents of labeling practices for GM crops. Finally, there was a positive correlation between the perception of benefits and attitudes towards GM crops.
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Language Wos 000373378100011 Publication Date 2015-06-04
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ISSN 1353-3452 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.229 Times cited 5 Open Access
Notes ; ; Approved Most recent IF: 2.229
Call Number UA @ admin @ c:irua:136751 Serial 6158
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