Records |
Author |
Samal, D.; Tan, H.; Takamura, Y.; Siemons, W.; Verbeeck, J.; Van Tendeloo, G.; Arenholz, E.; Jenkins, C.A.; Rijnders, G.; Koster, G. |
Title |
Direct structural and spectroscopic investigation of ultrathin films of tetragonal CuO: Six-fold coordinated copper |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Europhysics letters |
Abbreviated Journal |
Epl-Europhys Lett |
Volume |
105 |
Issue |
1 |
Pages |
17003-17005 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Unlike other 3d transition metal monoxides (MnO, FeO, CoO, and NiO), CuO is found in a low-symmetry distorted monoclinic structure rather than the rocksalt structure. We report here of the growth of ultrathin CuO films on SrTiO3 substrates; scanning transmission electron microscopy was used to show the stabilization of a tetragonal rocksalt structure with an elongated c-axis such that c/a similar to 1.34 and the Cu-O-Cu bond angle similar to 180 degrees, pointing to metastable six-fold coordinated Cu. X-ray absorption spectroscopy demonstrates that the hole at the Cu site for the CuO is localized in 3d(x2-y2) orbital unlike the well-studied monoclinic CuO phase. The experimental confirmation of the tetragonal structure of CuO opens up new avenues to explore electronic and magnetic properties of six-fold coordinated Cu. Copyright (C) EPLA, 2014 |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Paris |
Editor |
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Language |
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Wos |
000331197100015 |
Publication Date |
2014-01-30 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0295-5075;1286-4854; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.957 |
Times cited |
15 |
Open Access |
|
Notes |
This work was carried out with financial support from the AFOSR and EOARD projects (project No.: FA8655-10-1-3077) and also supported by funding from the European Research Council under the 7th Framework Program (FP7), ERC grant No. 246791 – COUNTATOMS, ERC Starting Grant 278510 VORTEX, Grant No. NMP3-LA-2010-246102 IFOX and an Integrated Infrastructure Initiative, reference No. 312483-ESTEEM2. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. Advanced Light Source is supported by the Office of Science, Office of Basic Energy Sciences of the U.S. Department of Energy (DOE) under Contract No. DE-AC02-05CH11231. YT acknowledges support from the National Science Foundation (DMR-0747896). WS was supported by the US DOE, Basic Energy Sciences, Materials Sciences and Engineering Division. ECASJO_; |
Approved |
Most recent IF: 1.957; 2014 IF: 2.095 |
Call Number |
UA @ lucian @ c:irua:115806UA @ admin @ c:irua:115806 |
Serial |
722 |
Permanent link to this record |
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Author |
Spreitzer, M.; Egoavil, R.; Verbeeck, J.; Blank, D.H.A.; Rijnders, G. |
Title |
Pulsed laser deposition of SrTiO3 on a H-terminated Si substrate |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Journal of materials chemistry C : materials for optical and electronic devices |
Abbreviated Journal |
J Mater Chem C |
Volume |
1 |
Issue |
34 |
Pages |
5216-5222 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Interfacing oxides with silicon is a long-standing problem related to the integration of multifunctional oxides with semiconductor devices and the replacement of SiO2 with high-k gate oxides. In our study, pulsed laser deposition was used to prepare a SrTiO3 (STO) thin film on a H-terminated Si substrate. The main purpose of our work was to verify the ability of H-termination against the oxidation of Si during the PLD process and to analyze the resulting interfaces. In the first part of the study, the STO was deposited directly on the Si, leading to the formation of a preferentially textured STO film with a (100) orientation. In the second part, SrO was used as a buffer layer, which enabled the partial epitaxial growth of STO with STO(110)parallel to Si(100) and STO[001]parallel to Si[001]. The change in the growth direction induced by the application of a SrO buffer was governed by the formation of a SrO(111) intermediate layer and subsequently by the minimization of the lattice misfit between the STO and the SrO. Under the investigated conditions, approximately 10 nm thick interfacial layers formed between the STO and the Si due to reactions between the deposited material and the underlying H-terminated Si. In the case of direct STO deposition, SiOx formed at the interface with the silicon, while in the case when SrO was used as a buffer, strontium silicate grew directly on the silicon, which improves the growth quality of the uppermost STO. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000322911900005 |
Publication Date |
2013-07-12 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
2050-7526;2050-7534; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.256 |
Times cited |
23 |
Open Access |
|
Notes |
Ifox; Esteem2; Vortex; Countatoms; esteem2jra3 ECASJO; |
Approved |
Most recent IF: 5.256; 2013 IF: NA |
Call Number |
UA @ lucian @ c:irua:110798UA @ admin @ c:irua:110798 |
Serial |
2739 |
Permanent link to this record |
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Author |
Egoavil, R.; Tan, H.; Verbeeck, J.; Bals, S.; Smith, B.; Kuiper, B.; Rijnders, G.; Koster, G.; Van Tendeloo, G. |
Title |
Atomic scale investigation of a PbTiO3/SrRuO3/DyScO3 heterostructure |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
102 |
Issue |
22 |
Pages |
223106-5 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
An epitaxial PbTiO3 thin film grown on self-organized crystalline SrRuO3 nanowires deposited on a DyScO3 substrate with ordered DyO and ScO2 chemical terminations is investigated by transmission electron microscopy. In this PbTiO3/SrRuO3/DyScO3 heterostructure, the SrRuO3 nanowires are assumed to grow on only one type of substrate termination. Here, we report on the structure, morphology, and chemical composition analysis of this heterostructure. Electron energy loss spectroscopy reveals the exact termination sequence in this complex structure. The energy loss near-edge structure of the Ti-L-2,L-3, Sc-L-2,L-3, and O K edges shows intrinsic interfacial electronic reconstruction. Furthermore, PbTiO3 domain walls are observed to start at the end of the nanowires resulting in atomic steps on the film surface. (C) 2013 AIP Publishing LLC. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000320621600070 |
Publication Date |
2013-06-05 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0003-6951; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.411 |
Times cited |
12 |
Open Access |
|
Notes |
Ifox; Esteem2; Countatoms; Vortex; esteem2jra3 ECASJO; |
Approved |
Most recent IF: 3.411; 2013 IF: 3.515 |
Call Number |
UA @ lucian @ c:irua:109606UA @ admin @ c:irua:109606 |
Serial |
185 |
Permanent link to this record |
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Author |
Samal, D.; Tan, H.; Molegraaf, H.; Kuiper, B.; Siemons, W.; Bals, S.; Verbeeck, J.; Van Tendeloo, G.; Takamura, Y.; Arenholz, E.; Jenkins, C.A.; Rijnders, G.; Koster, G. |
Title |
Experimental evidence for oxygen sublattice control in polar infinite layer SrCuO2 |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
Volume |
111 |
Issue |
9 |
Pages |
096102-96105 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
A recent theoretical study [ Phys. Rev. B 85 121411(R) (2012)] predicted a thickness limit below which ideal polar cuprates turn nonpolar driven by the associated electrostatic instability. Here we demonstrate this possibility by inducing a structural transformation from the bulk planar to chainlike structure upon reducing the SrCuO2 repeat thickness in SrCuO2/SrTiO3 superlattices with unit-cell precision. Our results, based on structural investigation by x-ray diffraction and high resolution scanning transmission electron microscopy, demonstrate that the oxygen sublattice can essentially be built by design. In addition, the electronic structure of the chainlike structure, as studied by x-ray absorption spectroscopy, shows the signature for preferential hole occupation in the Cu 3d3z2-r2 orbital, which is different from the planar case. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000323610800023 |
Publication Date |
2013-08-27 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0031-9007;1079-7114; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.462 |
Times cited |
29 |
Open Access |
|
Notes |
This work was carried out with financial support from AFOSR and EOARD project (Project No. FA8655-10-1-3077) and also supported by funding from the European Research Council under the 7th Framework Program (FP7), ERC Grant No. 246791-COUNTATOMS and ERC Starting Grant No. 278510 VORTEX. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. This work was partially funded by the European Union Council under the 7th Framework Program (FP7) Grant No. NMP3-LA-2010-246102 IFOX. The authors acknowledge financial support from the European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure No. 312483-ESTEEM2. Advanced Light Source is supported by the Office of Science, Office of Basic Energy Sciences of the U.S. Department of Energy (DOE) under Contract No. DE-AC02-05CH11231. Y. T. acknowledges support from the National Science Foundation (DMR-0747896). W. S. was supported by the US DOE, Basic Energy Sciences, Materials Sciences and Engineering Division. D. S. thanks Z. Zhong from Vienna University of Technology, Austria for scientific discussion. ECASJO_; |
Approved |
Most recent IF: 8.462; 2013 IF: 7.728 |
Call Number |
UA @ lucian @ c:irua:109452UA @ admin @ c:irua:109452 |
Serial |
1140 |
Permanent link to this record |
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Author |
Huijben, M.; Koster, G.; Kruize, M.K.; Wenderich, S.; Verbeeck, J.; Bals, S.; Slooten, E.; Shi, B.; Molegraaf, H.J.A.; Kleibeuker, J.E.; Van Aert, S.; Goedkoop, J.B.; Brinkman, A.; Blank, D.H.A.; Golden, M.S.; Van Tendeloo, G.; Hilgenkamp, H.; Rijnders, G.; |
Title |
Defect engineering in oxide heterostructures by enhanced oxygen surface exchange |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Advanced functional materials |
Abbreviated Journal |
Adv Funct Mater |
Volume |
23 |
Issue |
42 |
Pages |
5240-5248 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The synthesis of materials with well-controlled composition and structure improves our understanding of their intrinsic electrical transport properties. Recent developments in atomically controlled growth have been shown to be crucial in enabling the study of new physical phenomena in epitaxial oxide heterostructures. Nevertheless, these phenomena can be influenced by the presence of defects that act as extrinsic sources of both doping and impurity scattering. Control over the nature and density of such defects is therefore necessary to fully understand the intrinsic materials properties and exploit them in future device technologies. Here, it is shown that incorporation of a strontium copper oxide nano-layer strongly reduces the impurity scattering at conducting interfaces in oxide LaAlO3SrTiO3(001) heterostructures, opening the door to high carrier mobility materials. It is proposed that this remote cuprate layer facilitates enhanced suppression of oxygen defects by reducing the kinetic barrier for oxygen exchange in the hetero-interfacial film system. This design concept of controlled defect engineering can be of significant importance in applications in which enhanced oxygen surface exchange plays a crucial role. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Weinheim |
Editor |
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Language |
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Wos |
000327480900003 |
Publication Date |
2013-06-10 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1616-301X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.124 |
Times cited |
87 |
Open Access |
|
Notes |
Countatoms; Vortex; Fwo; Ifox ECASJO_; |
Approved |
Most recent IF: 12.124; 2013 IF: 10.439 |
Call Number |
UA @ lucian @ c:irua:109273UA @ admin @ c:irua:109273 |
Serial |
615 |
Permanent link to this record |
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Author |
Koster, G.; Verbist, K.; Rijnders, G.; Rogalla, H.; Van Tendeloo, G.; Blank, D.H.A. |
Title |
Structure and properties of (Sr,Ca)CuO2-BaCuO2 superlattices grown by pulsed laser interval deposition |
Type |
A1 Journal article |
Year |
2001 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
Volume |
353 |
Issue |
3-4 |
Pages |
167-183 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We report on the preparation of CuBa(2)(Sr(x)Ca(1-x))(n)Cu(n-1)O(y) compounds by fabrication of (Ba,Sr,Ca)CuO(2) superlattices with pulsed laser deposition (PLD). A technique called interval deposition is used to suppress multi-level or island growth resulting in high-quality superlattice structures. Both, the applicability of PLD to atomic engineering as well as the fabrication of artificial superconductors is demonstrated. The (Sr,Ca)CuO(2)-BaCuO(2) superlattices are characterized by X-ray diffraction, high-resolution electron microscopy (HREM) and selected area electron diffraction. The superlattice period has been deduced from electron diffraction patterns and XRD measurements. For Sr containing films, the best growth behavior is observed and films with the highest degree of crystallinity are obtained, whereas superconductivity is only found in less crystalline, Ca containing films. Under some deposition conditions and depending on the amount of Ba containing layers in the superlattice, it was observed that the BaCuO(2) material is converted to Ba(2)CuO(4-delta). Image simulations to interpret the HREM contrast are performed. (C) 2001 Elsevier Science B.V. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000168861100003 |
Publication Date |
2002-07-25 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0921-4534; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.404 |
Times cited |
8 |
Open Access |
|
Notes |
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Approved |
Most recent IF: 1.404; 2001 IF: 0.806 |
Call Number |
UA @ lucian @ c:irua:103417 |
Serial |
3293 |
Permanent link to this record |
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Author |
Bals, S.; Van Tendeloo, G.; Rijnders, G.; Huijben, M.; Leca, V.; Blank, D.H.A. |
Title |
Transmission electron microscopy on interface engineered superconducting thin films |
Type |
A1 Journal article |
Year |
2003 |
Publication |
IEEE transactions on applied superconductivity |
Abbreviated Journal |
Ieee T Appl Supercon |
Volume |
13 |
Issue |
2:3 |
Pages |
2834-2837 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Transmission electron microscopy is used to evaluate different deposition techniques, which optimize the microstructure and physical properties of superconducting thin films. High-resolution electron microscopy proves that the use of an YBa2Cu2Ox buffer layer can avoid a variable interface configuration in YBa2Cu3O7-delta thin films grown on SrTiO3. The growth can also be controlled at an atomic level by, using sub-unit cell layer epitaxy, which results in films with high quality and few structural defects. Epitaxial strain in Sr0.85La0.15CuO2 infinite layer thin films influences the critical temperature of these films, as well as the microstructure. Compressive stress is released by a modulated or a twinned microstructure, which eliminates superconductivity. On the other hand, also tensile strain seems to lower the critical temperature of the infinite layer. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000184242400101 |
Publication Date |
2003-07-16 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1051-8223; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
13 |
Open Access |
|
Notes |
Iuap V-1; Fwo |
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:103292 |
Serial |
3712 |
Permanent link to this record |