Records |
Author |
Liu, S.; Cool, P.; Collart, O.; van der Voort, P.; Vansant, E.F.; Lebedev, O.I.; Van Tendeloo, G.; Jiang, M. |
Title |
The influence of the alcohol concentration on the structural ordering of mesoporous silica: cosurfactant versus cosolvent |
Type |
A1 Journal article |
Year |
2003 |
Publication |
The journal of physical chemistry : B : condensed matter, materials, surfaces, interfaces and biophysical |
Abbreviated Journal |
J Phys Chem B |
Volume |
107 |
Issue |
|
Pages |
10405-10411 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000185401900013 |
Publication Date |
2003-09-18 |
Series Editor ![sorted by Series Editor field, ascending order (up)](img/sort_asc.gif) |
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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 |
1520-6106;1520-5207; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.177 |
Times cited |
134 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.177; 2003 IF: 3.679 |
Call Number |
UA @ lucian @ c:irua:46264 |
Serial |
1643 |
Permanent link to this record |
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Author |
Liu, S.; Lebedev, O.I.; Mertens, M.; Meynen, V.; Cool, P.; Van Tendeloo, G.; Vansant, E.F. |
Title |
The merging of silica-surfactant microspheres under hydrothermal conditions |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Microporous and mesoporous materials: zeolites, clays, carbons and related materials |
Abbreviated Journal |
Micropor Mesopor Mat |
Volume |
116 |
Issue |
|
Pages |
141-146 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
Abstract |
Post-synthesis hydrothermal treatments have been used to improve the quality of MCM-41 materials. In our latest work, merging of surfactant-containing silica microspheres during the hydrothermal treatments was observed. Mechanistic insights and the different stages that are involved in the merging process can be summarized as follows. First, the surfaces of the starting microspheres open up due to the dissolution of silica. Then the dissolved silica species provide mass source for the formation of particle necks connecting two neighboring microspheres. Gradually, surfaces of the starting microspheres are flattened to meet the needs of further growth of the necks. Finally, some chain-like highly-ordered mesoporous structures up to several micrometers are formed. The observed merging of the surfactant-containing microspheres is a re-assembling process, which is under the control of electrostatic force between the dissolved silica species and the surfactant cations. The occluded surfactant cations in the precursor spheres play important roles in the merging process. |
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 |
000261133600021 |
Publication Date |
2008-04-13 |
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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 |
1387-1811; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.615 |
Times cited |
5 |
Open Access |
|
Notes |
Fwo; Goa |
Approved |
Most recent IF: 3.615; 2008 IF: 2.555 |
Call Number |
UA @ lucian @ c:irua:72021 |
Serial |
1997 |
Permanent link to this record |
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Author |
Lebedev, O.I.; Turner, S.; Liu, S.; Cool, P.; Van Tendeloo, G. |
Title |
New nano-architectures of mesoporous silica spheres analyzed by advanced electron microscopy |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Nanoscale |
Abbreviated Journal |
Nanoscale |
Volume |
4 |
Issue |
5 |
Pages |
1722-1727 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
Abstract |
Using template-containing silica microspheres as a precursor, novel ordered mesoporous silica nanoparticles with a narrow pore size distribution and high crystallinity have been synthesized by various hydrothermal merging processes. Several architectures like chains, dumbbells, triangles, squares and flowers have been discovered. The linking mechanisms of these interacting silica spheres leading to the formation of ordered nano-structures are studied by HRTEM, HAADF-STEM and electron tomography and a plausible model is presented for several merging processes. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000300433700051 |
Publication Date |
2011-12-21 |
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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 |
2040-3364;2040-3372; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
7.367 |
Times cited |
5 |
Open Access |
|
Notes |
Fwo |
Approved |
Most recent IF: 7.367; 2012 IF: 6.233 |
Call Number |
UA @ lucian @ c:irua:95038 |
Serial |
2328 |
Permanent link to this record |
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Author |
Liu, S.; Rao, J.; Sui, X.; Cool, P.; Vansant, E.F.; Van Tendeloo, G.; Cheng, X. |
Title |
Preparation of hollow silica spheres with different mesostructures |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Journal of non-crystalline solids |
Abbreviated Journal |
J Non-Cryst Solids |
Volume |
354 |
Issue |
10/11 |
Pages |
826-830 |
Keywords |
A1 Journal article; Laboratory of adsorption and catalysis (LADCA); Electron microscopy for materials research (EMAT) |
Abstract |
Hollow silica spheres were quickly synthesized by an octylamine (OA) templating method using tetraethyl orthosilicate (TEOS) as the silica source. N2-sorption results indicate that the hollow spheres have high surface areas and pore volumes. XRD and TEM measurements reveal that the structure of the hollow spheres depends on the amount of TEOS used in the synthesis. When low amount of TEOS is added, the template-containing precursor spheres depict an XRD pattern with two peaks, which can be indexed to a lamellar phase. After the removal of the template, the obtained hollow spheres show no diffraction peaks in the XRD pattern, suggesting that the nanopores in the silica shells are disordered. If increasing the amount of TEOS, either the uncalcined or the calcined sample gives an XRD pattern with a single diffraction peak. The mesostructure of these hollow silica spheres is typically as HMS materials. TGA analyses suggest that the interaction between the silica species and surfactant is stronger in the latter 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 |
Amsterdam |
Editor |
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Language |
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Wos |
000253216700003 |
Publication Date |
2007-09-17 |
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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 |
0022-3093; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.124 |
Times cited |
26 |
Open Access |
|
Notes |
Gao |
Approved |
Most recent IF: 2.124; 2008 IF: 1.449 |
Call Number |
UA @ lucian @ c:irua:72018 |
Serial |
2703 |
Permanent link to this record |
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Author |
Liu, S.; Wei, M.; Sui, X.; Cheng, X.; Cool, P.; Van Tendeloo, G. |
Title |
A scanning electron microscopy study on hollow silica microspheres: defects and influences of the synthesis composition |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of sol-gel science and technology |
Abbreviated Journal |
J Sol-Gel Sci Techn |
Volume |
49 |
Issue |
3 |
Pages |
373-379 |
Keywords |
A1 Journal article; Laboratory of adsorption and catalysis (LADCA); Electron microscopy for materials research (EMAT) |
Abstract |
Defects on hollow silica spheres synthesized in a tetraethylorthosilicate-octylamine-HCl-H2O system were recorded by scanning microscope. Based on the results, influences of synthesis composition on the formation of these defects are discussed. It is evidenced that products prepared with different octylamine-to-tetraethylorthosilicate ratios may have surface depressions, cracks and non-hollow microspheres. However, by changing water and acid additions, these defects could be reduced or eliminated. Generally, samples synthesized with a large octylamine addition commonly exhibit surface depressions. A small octylamine or a large water addition benefits the formation of solid silica microspheres among the product. Acid, although is not indispensable for the formation of hollow spheres, helps to eliminate or reduce depressions on the hollow shells. It is explained that the added acid gives rise to a relative localized fast hydrolysis versus condensation, facilitating an easy mobility of hydrolyzed silica species, and consequently the shell surface is smoothened. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Kluwer |
Place of Publication |
Dordrecht |
Editor |
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Language |
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Wos |
000263260100015 |
Publication Date |
2008-12-16 |
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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 |
0928-0707;1573-4846; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.575 |
Times cited |
1 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.575; 2009 IF: 1.393 |
Call Number |
UA @ lucian @ c:irua:74962 |
Serial |
2941 |
Permanent link to this record |
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Author |
Tan, X.; McCabe, E.E.; Orlandi, F.; Manuel, P.; Batuk, M.; Hadermann, J.; Deng, Z.; Jin, C.; Nowik, I.; Herber, R.; Segre, C.U.; Liu, S.; Croft, M.; Kang, C.-J.; Lapidus, S.; Frank, C.E.; Padmanabhan, H.; Gopalan, V.; Wu, M.; Li, M.-R.; Kotliar, G.; Walker, D.; Greenblatt, M. |
Title |
MnFe0.5Ru0.5O3 : an above-room-temperature antiferromagnetic semiconductor |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Journal of materials chemistry C : materials for optical and electronic devices |
Abbreviated Journal |
J Mater Chem C |
Volume |
7 |
Issue |
3 |
Pages |
509-522 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
A transition-metal-only MnFe0.5Ru0.5O3 polycrystalline oxide was prepared by a reaction of starting materials MnO, MnO2, Fe2O3, RuO2 at 6 GPa and 1873 K for 30 minutes. A combination of X-ray and neutron powder diffraction refinements indicated that MnFe0.5Ru0.5O3 adopts the corundum (alpha-Fe2O3) structure type with space group R (3) over barc, in which all metal ions are disordered. The centrosymmetric nature of the MnFe0.5Ru0.5O3 structure is corroborated by transmission electron microscopy, lack of optical second harmonic generation, X-ray absorption near edge spectroscopy, and Mossbauer spectroscopy. X-ray absorption near edge spectroscopy of MnFe0.5Ru0.5O3 showed the oxidation states of Mn, Fe, and Ru to be 2+/3+, 3+, and similar to 4+, respectively. Resistivity measurements revealed that MnFe0.5Ru0.5O3 is a semiconductor. Magnetic measurements and magnetic structure refinements indicated that MnFe0.5Ru0.5O3 orders antiferromagnetically around 400 K, with magnetic moments slightly canted away from the c axis. Fe-57 Mossbauer confirmed the magnetic ordering and Fe3+ (S = 5/2) magnetic hyperfine splitting. First principles calculations are provided to understand the electronic structure more thoroughly. A comparison of synthesis and properties of MnFe0.5Ru0.5O3 and related corundum Mn2BB'O-6 derivatives is discussed. |
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 |
000458780300004 |
Publication Date |
2018-11-27 |
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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 |
2050-7526; 2050-7534 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.256 |
Times cited |
1 |
Open Access |
Not_Open_Access |
Notes |
; M. G. thanks the NSF-DMR-1507252 grant of the United States. X. T. was supported by the “Center for Computational Design of Functional Strongly Correlated Materials and Theoretical Spectroscopy'' under DOE Grant No. DE-FOA-0001276. G. K. and C. J. K. were supported by the Air Force Office of Scientific Research. MRCAT operations are supported by the Department of Energy and the MRCAT member institutions. EEM is grateful to the Leverhulme Trust (RPG-2017-362). M. R. Li and M. X. Wu are supported by the ”One Thousand Youth Talents'' Program of China. Use of the Advanced Photon Source at Argonne National Laboratory was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. Part of this research used the ISS, 8-ID and TES, 8-BM beamlines at the National Synchrotron Light Source II (NSLS-II), a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Brookhaven National Laboratory under Contract No. DE-SC0012704. Without the valuable aid/support of the NSLS-II staff scientists Eli Stavitski, Klaus Attenkofer, and Paul Northrup this phase of the work could not have been performed. The work at IOPCAS was supported by NSF & MOST of China through research projects. H. R. and V. G. acknowledge NSF-MRSEC Center for Nanoscale Science at Penn State through the grant number DMR-1420620. The authors would like to thank Ms Jean Hanley at Lamont-Doherty Earth Observatory in Columbia University for making the high-pressure assemblies. The authors acknowledge the science and technology facility council (STFC) UK for the provision of neutron beam time. The authors would like to thank Daniel Nye for help on the Rigaku SmartLab X-ray diffractometer instrument in the Materials Characterization Laboratory at the ISIS Neutron and Muon Source. ; |
Approved |
Most recent IF: 5.256 |
Call Number |
UA @ admin @ c:irua:157564 |
Serial |
5264 |
Permanent link to this record |
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Author |
Zhang, Z.; Chen, X.; Shi, X.; Hu, Y.; Huang, J.; Liu, S.; Ren, Z.; Huang, H.; Han, G.; Van Tendeloo, G.; Tian, H. |
Title |
Morphotropic phase boundary in pure perovskite lead titanate at room temperature |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Materials Today Nano |
Abbreviated Journal |
|
Volume |
20 |
Issue |
|
Pages |
100275-5 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
For many decades, great efforts have been devoted to pursue a large piezoelectric response by an intelligent design of morphotropic phase boundaries (MPB) in solid solutions, where tetragonal (T) and rhombohedral (R) structures coexist. For example, classical PbZrxTi1-xO3 and Pb(Mg1/3Nb2/3)O-3-PbTiO3 single crystals demonstrate a giant piezoelectric response near MPB. However, as the end member of these solids, perovskite-structured PbTiO3 always adopts the T phase at room temperature. Here, we report a pathway to create room temperature MPB in a single-phase PbTiO3. The uniaxial stress along the c-axis drives a T-R phase transition bridged by a monoclinic (M) phase, which facilitates a polarization rotation in the monodomain PbTiO3. Meanwhile, we demonstrate that the coexistence of T and R phases at room temperature can be achieved via an extremely mismatched heterointerface system. The uniaxial pressure is proved as an efficient way to break the inherent symmetry and able to substantially tailor the phase transition temperature Tc. These findings provide new insights into MPB, offering the opportunity to explore the giant piezoelectric response in single-phase materials. (c) 2022 Elsevier Ltd. 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 |
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Editor |
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Language |
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Wos |
000906548600002 |
Publication Date |
2022-10-18 |
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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 |
2588-8420 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
10.3 |
Times cited |
|
Open Access |
Not_Open_Access |
Notes |
|
Approved |
Most recent IF: 10.3 |
Call Number |
UA @ admin @ c:irua:193477 |
Serial |
7324 |
Permanent link to this record |