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Barreca, D.; Carraro, G.; Maccato, C.; Altantzis, T.; Kaunisto, K.; Gasparotto, A. | ||||
Title | Controlled Growth of Supported ZnO Inverted Nanopyramids with Downward Pointing Tips | Type | A1 Journal article | ||
Year | 2018 | Publication | Crystal growth & design | Abbreviated Journal | Cryst Growth Des |
Volume | Issue | Pages | acs.cgd.8b00198 | ||
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | High purity porous ZnO nanopyramids with controllable properties are grown on their tips on Si(100) substrates by means of a catalyst-free vapor phase deposition route in a wet oxygen reaction environment. The system degree of preferential [001] orientation, as well as nanopyramid size, geometrical shape and density distribution, can be finely tuned by varying the growth temperature between 300 and 400°C, whereas higher temperatures lead to more compact systems with a three-dimensional (3D) morphology. A growth mechanism of the obtained ZnO nanostructures based on a self-catalytic vapor-solid (VS) mode is proposed, in order to explain the evolution of nanostructure morphologies as a function of the adopted process conditions. The results obtained by a thorough chemico-physical characterization enable to get an improved control over the properties of ZnO nanopyramids grown by this technique. Taken together, they are of noticeable importance not only for fundamental research on ZnO nanomaterials with controlled nano-organization, but also to tailor ZnO functionalities in view of various potential applications. |
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000429508200073 | Publication Date | 2018-03-06 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1528-7483 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.055 | Times cited | 6 | Open Access | OpenAccess |
Notes | This work has been supported by Padova University ex-60% 2015–2017, P-DiSC #03BIRD2016-UNIPD projects and ACTION post-doc fellowship. T. A. acknowledges a postdoctoral grant from the Research Foundation Flanders (FWO, Belgium). Thanks are also due to Dr. Rosa Calabrese (Department of Chemical Sciences, Padova University, Italy) and to Dr. T.-P. Ruoko (Department of Chemistry and Bioengineering, Tampere University of Technology, Finland) for skilful technical support. | Approved | Most recent IF: 4.055 | ||
Call Number | EMAT @ emat @c:irua:149514 | Serial | 4904 | ||
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Barreca, D.; Gasparotto, A.; Maccato, C.; Tondello, E.; Lebedev, O.I.; Van Tendeloo, G. | ||||
Title | CVD of copper oxides from a \beta-diketonate diamine precursor: tailoring the nano-organization | Type | A1 Journal article | ||
Year | 2009 | Publication | Crystal growth & design | Abbreviated Journal | Cryst Growth Des |
Volume | 9 | Issue | 5 | Pages | 2470-2480 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | A copper(II) hexafluoroacetylacetonate (1,1,1,5,5,5-hexafluoro-2,4-pentanedionate, hfa) adduct with N,N,N¡ä,N¡ä-tetramethylethylenediamine (TMEDA) [Cu(hfa)2¡¤TMEDA] is used for the first time as precursor for the chemical vapor deposition (CVD) of copper oxide nanosystems. The syntheses are carried out under both O2 and O2+H2O reaction atmospheres on Si(100) substrates, at temperatures ranging between 250 and 550 ¡ãC. Subsequently, the interrelations between the preparative conditions and the system composition, nanostructure, and morphology are elucidated by means of complementary analytical techniques [Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron and X-ray excited auger electron spectroscopies (XPS and XE-AES), glancing incidence X-ray diffraction (GIXRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM)]. The obtained data revealed a gradual transformation from Cu2O, to Cu2O + CuO, to CuO nanosystems upon increasing the deposition temperature from 250 to 550 ¡ãC under both growth atmospheres. Such a phenomenon was accompanied by a progressive morphological evolution from continuous films to 1D hyperbranched nanostructures. Water vapor introduction in the deposition environment enabled to lower the deposition temperature and resulted in a higher aggregate interconnection, attributed to a higher density of nucleation centers. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000265892200066 | Publication Date | 2009-05-06 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1528-7483;1528-7505; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.055 | Times cited | 60 | Open Access | |
Notes | Esteem 026019 | Approved | Most recent IF: 4.055; 2009 IF: 4.162 | ||
Call Number | UA @ lucian @ c:irua:77053 | Serial | 597 | ||
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Bekermann, D.; Gasparotto, A.; Barreca, D.; Bovo, L.; Devi, A.; Fischer, R.A.; Lebedev, O.I.; Maccato, C.; Tondello, E.; Van Tendeloo, G. | ||||
Title | Highly oriented ZnO nanorod arrays by a novel plasma chemical vapor deposition process | Type | A1 Journal article | ||
Year | 2010 | Publication | Crystal growth & design | Abbreviated Journal | Cryst Growth Des |
Volume | 10 | Issue | 4 | Pages | 2011-2018 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Strongly c-axis oriented ZnO nanorod arrays were grown on Si(100) by plasma enhanced-chemical vapor deposition (PE-CVD) starting from two volatile bis(ketoiminato) zinc(II) compounds Zn[(R′)NC(CH3)═C(H)C(CH3)═O]2, with R′ = -(CH2)xOCH3 (x = 2, 3). A systematic investigation of process parameters enabled us to obtain the selective formation of ZnO nanorods with tailored features, and provided an important insight into their growth mechanism. The morphology, structure, and composition of the synthesized ZnO nanosystems were thoroughly analyzed by field emission-scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDXS), glancing incidence X-ray diffraction (GIXRD), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). Photoluminescence (PL) measurements were carried out to gain information on the optical properties. Specifically, one-dimensional (1D) ZnO architectures could be grown on Si(100) substrates at temperatures as low as 200−300 °C and radio frequency (RF)-power values of 20 W, provided that a sufficiently high mass supply to the growth surface was maintained. To the best of our knowledge, the present work reports the mildest preparation conditions ever appeared in the literature for the PE-CVD of ZnO nanorods, a key result in view of potential large-scale technological applications. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000276234500080 | Publication Date | 2010-03-18 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1528-7483;1528-7505; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.055 | Times cited | 75 | Open Access | |
Notes | Esteem 026019 | Approved | Most recent IF: 4.055; 2010 IF: 4.390 | ||
Call Number | UA @ lucian @ c:irua:82311 | Serial | 1472 | ||
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Drijkoningen, S.; Pobedinskas, P.; Korneychuk, S.; Momot, A.; Balasubramaniam, Y.; Van Bael, M.K.; Turner, S.; Verbeeck, J.; Nesladekt, M.; Haenen, K. | ||||
Title | On the Origin of Diamond Plates Deposited at Low Temperature | Type | A1 Journal article | ||
Year | 2017 | Publication | Crystal growth & design | Abbreviated Journal | Cryst Growth Des |
Volume | 17 | Issue | 8 | Pages | 4306-4314 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The crucial requirement for diamond growth at low temperatures, enabling a wide range of new applications, is a high plasma density at a low gas pressure, which leads to a low thermal load onto sensitive substrate materials. While these conditions are not within reach for resonance cavity plasma systems, linear antenna microwave delivery systems allow the deposition of high quality diamond films at temperatures around 400 degrees C and at pressures below 1 mbar. In this work the codeposition of high quality plates and octahedral diamond grains in nanocrystalline films is reported. In contrast to previous reports claiming the need for high temperatures (T >= 850 degrees C), low temperatures (320 degrees C <= T <= 410 degrees C) were sufficient to deposit diamond plate structures. Cross-sectional high resolution transmission electron microscopy studies show that these plates are faulty cubic diamond terminated by large {111} surface facets with very little sp(2) bonded carbon in the grain boundaries. Raman and electron energy loss spectroscopy studies confirm a high diamond quality, above 93% sp(3) carbon content. Three potential mechanisms, that can account for the initial development of the observed plates rich with stacking faults, and are based on the presence of impurities, are proposed. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000407089600031 | Publication Date | 2017-06-30 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1528-7483 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.055 | Times cited | 23 | Open Access | Not_Open_Access |
Notes | ; The Research Foundation – Flanders (FWO) is gratefully acknowledged for financial support in the form of the Postdoctoral Fellowships of P.P. and S.T., contract G.0044.13N “Charge ordering” (S.K., J.V.), the Methusalem “Nano” network, and the Hercules-linear antenna and Raman equipment. ; | Approved | Most recent IF: 4.055 | ||
Call Number | UA @ lucian @ c:irua:145735UA @ admin @ c:irua:145735 | Serial | 4746 | ||
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Eckert, M.; Neyts, E.; Bogaerts, A. | ||||
Title | Differences between ultrananocrystalline and nanocrystalline diamond growth: theoretical investigation of CxHy species at diamond step edges | Type | A1 Journal article | ||
Year | 2010 | Publication | Crystal growth & design | Abbreviated Journal | Cryst Growth Des |
Volume | 10 | Issue | 9 | Pages | 4123-4134 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | The behavior of hydrocarbon species at step edges of diamond terraces is investigated by means of combined molecular dynamics−Metropolis Monte Carlo simulations. The results show that the formation of ballas-like diamond films (like UNCD) and well-faceted diamond films (like NCD) can be related to the gas phase concentrations of CxHy in a new manner: Species that have high concentrations above the growing UNCD films suppress the extension of step edges through defect formation. The species that are present above the growing NCD film, however, enhance the extension of diamond terraces, which is believed to result in well-faceted diamond films. Furthermore, it is shown that, during UNCD growth, CxHy species with x ≥ 2 play an important role, in contrast to the currently adopted CVD diamond growth mechanism. Finally, the probabilities for the extension of the diamond (100) terrace are much higher than those for the diamond (111) terrace, which is in full agreement with the experimental observation that diamond (100) facets are more favored than diamond (111) facets during CVD diamond growth. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000281353900042 | Publication Date | 2010-08-16 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1528-7483;1528-7505; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.055 | Times cited | 11 | Open Access | |
Notes | Approved | Most recent IF: 4.055; 2010 IF: 4.390 | |||
Call Number | UA @ lucian @ c:irua:83696 | Serial | 694 | ||
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Eckert, M.; Neyts, E.; Bogaerts, A. | ||||
Title | Insights into the growth of (ultra)nanocrystalline diamond by combined molecular dynamics and Monte Carlo simulations | Type | A1 Journal article | ||
Year | 2010 | Publication | Crystal growth & design | Abbreviated Journal | Cryst Growth Des |
Volume | 10 | Issue | 7 | Pages | 3005-3021 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | In this paper, we present the results of combined molecular dynamics−Metropolis Monte Carlo (MD-MMC) simulations of hydrocarbon species at flat diamond (100)2 × 1 and (111)1 × 1 surfaces. The investigated species are considered to be the most important growth species for (ultra)nanocrystalline diamond ((U)NCD) growth. When applying the MMC algorithm to stuck species at monoradical sites, bonding changes are only seen for CH2. The sequence of the bond breaking and formation as put forward by the MMC simulations mimics the insertion of CH2 into a surface dimer as proposed in the standard growth model of diamond. For hydrocarbon species attached to two adjacent radical (biradical) sites, the MMC simulations give rise to significant changes in the bonding structure. For UNCD, the combinations of C3 and C3H2, and C3 and C4H2 (at diamond (100)2 × 1) and C and C2H2 (at diamond (111)1 × 1) are the most successful in nucleating new crystal layers. For NCD, the following combinations pursue the diamond structure the best: C2H2 and C3H2 (at diamond (100)2 × 1) and CH2 and C2H2 (at diamond (111)1 × 1). The different behaviors of the hydrocarbon species at the two diamond surfaces are related to the different sterical hindrances at the diamond surfaces. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000279422700032 | Publication Date | 2010-05-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1528-7483;1528-7505; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.055 | Times cited | 13 | Open Access | |
Notes | Approved | Most recent IF: 4.055; 2010 IF: 4.390 | |||
Call Number | UA @ lucian @ c:irua:83065 | Serial | 1675 | ||
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Georgieva, V.; Voter, A.F.; Bogaerts, A. | ||||
Title | Understanding the surface diffusion processes during magnetron sputter-deposition of complex oxide Mg-Al-O thin films | Type | A1 Journal article | ||
Year | 2011 | Publication | Crystal growth & design | Abbreviated Journal | Cryst Growth Des |
Volume | 11 | Issue | 6 | Pages | 2553-2558 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | It is known that film structure may change dramatically with the extent of surface diffusion during the film growth process. In the present work, surface diffusion, induced thermally or activated by energetic impacts, is investigated theoretically under conditions appropriate for magnetron sputter-deposition of MgAlO thin films with varying stoichiometry. The distribution of surface diffusion energy barriers available to the system was determined for each stoichiometry, which allowed assessing in a qualitative way how much surface diffusion will take place on the time scale available between deposition events. The activation energy barriers increase with the Al concentration in the film, and therefore, the surface diffusion rates in the time frame of typical deposition rates drop, which can explain the decrease in crystallinity in the film structure and the transition to amorphous structure. The deposition process and the immediate surface diffusion enhanced by the energetic adatoms are simulated by means of a molecular dynamics model. The longer-time thermal surface diffusion and the energy landscape are studied by the temperature accelerated dynamics method, applied in an approximate way. The surface diffusion enhanced by the energetic impacts appears to be very important for the film structure in the low-temperature deposition regime. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000291074600068 | Publication Date | 2011-04-11 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1528-7483;1528-7505; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.055 | Times cited | 14 | Open Access | |
Notes | Approved | Most recent IF: 4.055; 2011 IF: 4.720 | |||
Call Number | UA @ lucian @ c:irua:89566 | Serial | 3806 | ||
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Hoang, D.-Q.; Pobedinskas, P.; Nicley, S.S.; Turner, S.; Janssens, S.D.; Van Bael, M.K.; D'Haen, J.; Haenen, K. | ||||
Title | Elucidation of the Growth Mechanism of Sputtered 2D Hexagonal Boron Nitride Nanowalls | Type | A1 Journal article | ||
Year | 2016 | Publication | Crystal growth & design | Abbreviated Journal | Cryst Growth Des |
Volume | 16 | Issue | 7 | Pages | 3699-3708 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Hexagonal boron nitride nanowall thin films were deposited on Si(100) substrates using a Ar(51%)/N-2(44%)/H-2(5%) gas mixture by unbalanced radio frequency sputtering. The effects of various target-to-substrate distances, substrate temperatures, and substrate tilting angles were investigated. When the substrate is close to the target, hydrogen etching plays a significant role in the film growth, while the effect is negligible for films deposited at a farther distance. The relative quantity of defects was measured by a non-destructive infrared spectroscopy technique that characterized the hydrogen incorporation at dangling nitrogen bonds at defect sites in the deposited films. Despite the films deposited at different substrate tilting angles, the nanowalls of those films were found to consistently grow vertical to the substrate surface, independent of the tilting angle. This implies that chemical processes, rather than physical ones, govern the growth of the nanowalls. The results also reveal that the degree of nanowall crystallization is tunable by varying the growth parameters. Finally, evidence of hydrogen desorption during vacuum annealing is given based on measurements of infrared stretching (E-1u) and bending (A(2u)) modes of the optical phonons, and the H-N vibration mode. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000379456700020 | Publication Date | 2016-05-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1528-7483 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.055 | Times cited | 8 | Open Access | |
Notes | Approved | Most recent IF: 4.055 | |||
Call Number | UA @ lucian @ c:irua:144690 | Serial | 4652 | ||
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Li, Y.; Tan, H.; Lebedev, O.; Verbeeck, J.; Biermans, E.; Van Tendeloo, G.; Su, B.-L. | ||||
Title | Insight into the growth of multiple branched MnOOH nanorods | Type | A1 Journal article | ||
Year | 2010 | Publication | Crystal growth & design | Abbreviated Journal | Cryst Growth Des |
Volume | 10 | Issue | 7 | Pages | 2969-2976 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Multiple branched manganese oxide hydroxide (MnOOH) nanorods prepared by a hydrothermal process were extensively studied by transmission electron microscopy (TEM). A model of the branch formation is proposed together with a study of the interface structure. The sword-like tip plays a crucial role for the nanorods to form different shapes. Importantly, the branching occurs at an angle of around either 57 degrees or 123 degrees. Specifically, a (111) twin plane can only be formed at the interface with a 123 degrees angle. The interfaces formed with a 57 degrees angle usually contain edge dislocations. Electron energy loss spectroscopy (EELS) demonstrates that the whole crystal has a uniform chemical composition. Interestingly, an epitaxial growth of Mn3O4 at the radial surface was also observed under electron beam irradiation; this is because of the rough purification of the products. The proposed mechanism is expected to shed light on the branched/dendrite nanostructure growth and to provide opportunities for further novel nanomaterial structure growth and design. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000279422700027 | Publication Date | 2010-06-08 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1528-7483;1528-7505; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.055 | Times cited | 41 | Open Access | |
Notes | Fwo; Esteem 026019 | Approved | Most recent IF: 4.055; 2010 IF: 4.390 | ||
Call Number | UA @ lucian @ c:irua:83886UA @ admin @ c:irua:83886 | Serial | 1672 | ||
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Neira, I.S.; Kolen'ko, Y.V.; Lebedev, O.I.; Van Tendeloo, G.; Gupta, H.S.; Guitián, F.; Yoshimura, M. | ||||
Title | An effective morphology control of hydroxyapatite crystals via hydrothermal synthesis | Type | A1 Journal article | ||
Year | 2009 | Publication | Crystal growth & design | Abbreviated Journal | Cryst Growth Des |
Volume | 9 | Issue | 1 | Pages | 466-474 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | A facile urea-assisted hydrothermal synthesis and systematic characterization of hydroxyapatite (HA) with calcium nitrate tetrahydrate and diammonium hydrogen phosphate as precursors are reported. The advantage of the proposed technique over previously reported synthetic approaches is the simple but precise control of the HA crystals morphology, which is achieved by employing an intensive, stepwise, and slow thermal decomposition of urea as well as varying initial concentrations of starting reagents. Whereas the plate-, hexagonal prism- and needle-like HA particles preferentially growth along the c-axis, the smaller and fine-plate-like HA crystals demonstrate crystal growth along the (102) and (211) directions, uncommon for HA. Furthermore, it was established that the hydrothermally derived powdered products are phase-pure HA containing CO32− anions in the crystal lattice, that is, AB-type carbonated hydroxyapatite. Transmission electron microscopy (TEM) and electron diffraction (ED) of selected samples reveal that the as-prepared HA crystals are single-crystalline and exhibit a nearly defect-free microstructure. The hardness and elastic modulus of the hexagonal prism-like HA crystals have been investigated on a nanoscale using the nanoindentation technique; the observed trends are discussed. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000262332700073 | Publication Date | 2008-11-21 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 1528-7483;1528-7505; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.055 | Times cited | 183 | Open Access | |
Notes | Esteem 026019 | Approved | Most recent IF: 4.055; 2009 IF: 4.162 | ||
Call Number | UA @ lucian @ c:irua:75740 | Serial | 853 | ||
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