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Author |
Batuk, M.; Vandemeulebroucke, D.; Ceretti, M.; Paulus, W.; Hadermann, J. |
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Title |
Topotactic redox cycling in SrFeO2.5+δ explored by 3D electron diffraction in different gas atmospheres |
Type |
A1 Journal article |
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Year |
2022 |
Publication |
Journal of materials chemistry A : materials for energy and sustainability |
Abbreviated Journal |
J Mater Chem A |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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For oxygen conducting materials applied in solid oxide fuel cells and chemical-looping processes, the understanding of the oxygen diffusion mechanism and the materials’ crystal structure at different stages of the redox reactions is a key parameter to control their performance. In this paper we report the first ever in situ 3D ED experiment in a gas environment and with it uncover the structure evolution of SrFeO2.5 as notably different from that reported from in situ X-ray and in situ neutron powder diffraction studies in gas environments. Using in situ 3D ED on submicron sized single crystals obtained from a high quality monodomain SrFeO2.5 single crystal , we observe the transformation under O2 flow of SrFeO2.5 with an intra- and interlayer ordering of the left and right twisted (FeO4) tetrahedral chains (space group Pcmb) into consecutively SrFeO2.75 with space group Cmmm (at 350°C, 33% O2) and SrFeO3-δ with space group Pm3 ̅m (at 400°C, 100% O2). Upon reduction in H2 flow, the crystals return to the brownmillerite structure with intralayer order, but without regaining the interlayer order of the pristine crystals. Therefore, redox cycling of SrFeO2.5 crystals in O2 and H2 introduces stacking faults into the structure, resulting in an I2/m(0βγ)0s symmetry with variable β. |
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000891928400001 |
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0000-00-00 |
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ISSN |
2050-7488 |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
11.9 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
Financial support is acknowledged from the FWO-Hercules fund I003218N ‘Infrastructure for imaging nanoscale processes in gas/vapor or liquid environments’, from the University of Antwerp through grant BOF TOP 38689. This work was supported by the European Commission Horizon 2020 NanED grant number 956099. Financial support from the French National Research Agency (ANR) through the project “Structural induced Electronic Complexity controlled by low temperature Topotactic Reaction” (SECTOR No. ANR-14-CE36- 0006-01) is gratefully acknowledged. |
Approved |
Most recent IF: 11.9 |
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Call Number |
EMAT @ emat @c:irua:192325 |
Serial |
7229 |
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Author |
van der Sluijs, M.M.; Salzmann, B.B.V.; Arenas Esteban, D.; Li, C.; Jannis, D.; Brafine, L.C.; Laning, T.D.; Reinders, J.W.C.; Hijmans, N.S.A.; Moes, J.R.; Verbeeck, J.; Bals, S.; Vanmaekelbergh, D. |
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Title |
Study of the Mechanism and Increasing Crystallinity in the Self-Templated Growth of Ultrathin PbS Nanosheets |
Type |
A1 Journal article |
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Year |
2023 |
Publication |
Chemistry of materials |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Colloidal 2D semiconductor nanocrystals, the analogue of solid-state quantum wells, have attracted strong interest in material science and physics. Molar quantities of suspended quantum objects with spectrally pure absorption and emission can be synthesized. For the visible region, CdSe nanoplatelets with atomically precise thickness and tailorable emission have been (almost) perfected. For the near-infrared region, PbS nanosheets (NSs) hold strong promise, but the photoluminescence quantum yield is low and many questions on the crystallinity, atomic structure, intriguing rectangular shape, and formation mechanism remain to be answered. Here, we report on a detailed investigation of the PbS NSs prepared with a lead thiocyanate single source precursor. Atomically resolved HAADF-STEM imaging reveals the presence of defects and small cubic domains in the deformed orthorhombic PbS crystal lattice. Moreover, variations in thickness are observed in the NSs, but only in steps of 2 PbS monolayers. To study the reaction mechanism, a synthesis at a lower temperature allowed for the study of reaction intermediates. Specifically, we studied the evolution of pseudo-crystalline templates towards mature, crystalline PbS NSs. We propose a self-induced templating mechanism based on an oleylamine-lead-thiocyanate (OLAM-Pb-SCN) complex with two Pb-SCN units as a building block; the interactions between the long-chain ligands regulate the crystal structure and possibly the lateral dimensions. |
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Wos |
000959572100001 |
Publication Date |
2023-03-25 |
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ISSN |
0897-4756 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
8.6 |
Times cited |
2 |
Open Access |
OpenAccess |
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Notes |
H2020 Research Infrastructures, 731019 ; H2020 European Research Council, 692691 815128 ; Nederlandse Organisatie voor Wetenschappelijk Onderzoek, 715.016.002 ; |
Approved |
Most recent IF: 8.6; 2023 IF: 9.466 |
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Call Number |
EMAT @ emat @c:irua:195894 |
Serial |
7255 |
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Author |
de la Encarnación, C.; Jungwirth, F.; Vila-Liarte, D.; Renero-Lecuna, C.; Kavak, S.; Orue, I.; Wilhelm, C.; Bals, S.; Henriksen-Lacey, M.; Jimenez de Aberasturi, D.; Liz-Marzán, L.M. |
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Title |
Hybrid core–shell nanoparticles for cell-specific magnetic separation and photothermal heating |
Type |
A1 Journal article |
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Year |
2023 |
Publication |
Journal of materials chemistry B : materials for biology and medicine |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Hyperthermia, as the process of heating a malignant site above 42 °C to trigger cell death, has emerged as an effective and selective cancer therapy strategy. Various modalities of hyperthermia have been proposed, among which magnetic and photothermal hyperthermia are known to benefit from the use of nanomaterials. In this context, we introduce herein a hybrid colloidal nanostructure comprising plasmonic gold nanorods (AuNRs) covered by a silica shell, onto which iron oxide nanoparticles (IONPs) are subsequently grown. The resulting hybrid nanostructures are responsive to both external magnetic fields and near-infrared irradiation. As a result, they can be applied for the targeted magnetic separation of selected cell populations – upon targeting by antibody functionalization – as well as for photothermal heating. Through this combined functionality, the therapeutic effect of photothermal heating can be enhanced. We demonstrate both the fabrication of the hybrid system and its application for targeted photothermal hyperthermia of human glioblastoma cells. |
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Wos |
000968908400001 |
Publication Date |
2023-04-05 |
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ISSN |
2050-750X |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
7 |
Times cited |
1 |
Open Access |
OpenAccess |
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Notes |
Ministerio de Ciencia e Innovación, PID2019-108854RA-I00 ; H2020 European Research Council, ERC AdG 787510, 4DBIOSERS ERC CoG 815128, REALNANO ; Fonds Wetenschappelijk Onderzoek, PhD research grant 1181122N ; |
Approved |
Most recent IF: 7; 2023 IF: 4.543 |
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Call Number |
EMAT @ emat @c:irua:195879 |
Serial |
7261 |
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Author |
Tampieri, F.; Espona-Noguera, A.; Labay, C.; Ginebra, M.-P.; Yusupov, M.; Bogaerts, A.; Canal, C. |
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Title |
Does non-thermal plasma modify biopolymers in solution? A chemical and mechanistic study for alginate |
Type |
A1 Journal Article |
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Year |
2023 |
Publication |
Biomaterials Science |
Abbreviated Journal |
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Keywords |
A1 Journal Article; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; |
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Abstract |
In the last decades, non-thermal plasma has been extensively investigated as a relevant tool for various biomedical applications, ranging from tissue decontamination to regeneration and from skin treatment to tumor therapies. This high versatility is due to the different kinds and amount of reactive oxygen and nitrogen species that can be generated during a plasma treatment and put in contact with the biological target. Some recent studies report that solutions of biopolymers with the ability to generate hydrogels, when treated with plasma, can enhance the generation of reactive species and influence their stability, resulting thus in the ideal media for indirect treatments of biological targets. The direct effects of the plasma treatment on the structure of biopolymers in water solution, as well as the chemical mechanisms responsible for the enhanced generation of RONS, are not yet fully understood. In this study, we aim at filling this gap by investigating, on the one hand, the nature and extent of the modifications induced by plasma treatment in alginate solutions, and, on the other hand, at using this information to explain the mechanisms responsible for the enhanced generation of reactive species as a consequence of the treatment. The approach we use is twofold: (i) investigating the effects of plasma treatment on alginate solutions, by size exclusion chromatography, rheology and scanning electron microscopy and (ii) study of a molecular model (glucuronate) sharing its chemical structure, by chromatography coupled with mass spectrometry and by molecular dynamics simulations. Our results point out the active role of the biopolymer chemistry during direct plasma treatment. Short-lived reactive species, such as OH radicals and O atoms, can modify the polymer structure, affecting its functional groups and causing partial fragmentation. Some of these chemical modifications, like the generation of organic peroxide, are likely responsible for the secondary generation of long-lived reactive species such as hydrogen peroxide and nitrite ions. This is relevant in view of using biocompatible hydrogels as vehicles for storage and delivery reactive species for targeted therapies. |
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Wos |
000973699000001 |
Publication Date |
2023-04-11 |
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Edition |
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ISSN |
2047-4830 |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.6 |
Times cited |
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Open Access |
Not_Open_Access |
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Notes |
Agència de Gestió d’Ajuts Universitaris i de Recerca, SGR2022-1368 ; H2020 European Research Council, 714793 ; European Cooperation in Science and Technology, CA19110 CA20114 ; Secretaría de Estado de Investigación, Desarrollo e Innovación, PID2019-103892RB-I00/AEI/10.13039/501100011033 ; We thank Gonzalo Rodríguez Cañada and Xavier Solé-Martí (Universitat Politècnica de Catalunya) for help in collecting some of the experimental data and for the useful discussions. This work has been primarily funded by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant agreement no. 714793). The authors acknowledge MINECO for PID2019103892RB-I00/AEI/10.13039/501100011033 project (CC). The authors belong to SGR2022-1368 (FT, AEN, CL, MPG, CC) and acknowledge Generalitat de Catalunya for the ICREA Academia Award for Excellence in Research of CC. We thank also COST Actions CA20114 (Therapeutical Applications of Cold Plasmas) and CA19110 (Plasma Applications for Smart and Sustainable Agriculture) for the stimulating environment provided. |
Approved |
Most recent IF: 6.6; 2023 IF: 4.21 |
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Call Number |
PLASMANT @ plasmant @c:irua:196773 |
Serial |
8794 |
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Permanent link to this record |
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Author |
Vlasov, E.; Skorikov, A.; Sánchez-Iglesias, A.; Liz-Marzán, L.M.; Verbeeck, J.; Bals, S. |
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Title |
Secondary electron induced current in scanning transmission electron microscopy: an alternative way to visualize the morphology of nanoparticles |
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A1 Journal article |
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Year |
2023 |
Publication |
ACS materials letters |
Abbreviated Journal |
ACS Materials Lett. |
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Volume |
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Issue |
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Pages |
1916-1921 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Electron tomography (ET) is a powerful tool to determine the three-dimensional (3D) structure of nanomaterials in a transmission electron microscope. However, the acquisition of a conventional tilt series for ET is a time-consuming process and can therefore not provide 3D structural information in a time-efficient manner. Here, we propose surface-sensitive secondary electron (SE) imaging as an alternative to ET for the investigation of the morphology of nanomaterials. We use the SE electron beam induced current (SEEBIC) technique that maps the electrical current arising from holes generated by the emission of SEs from the sample. SEEBIC imaging can provide valuable information on the sample morphology with high spatial resolution and significantly shorter throughput times compared with ET. In addition, we discuss the contrast formation mechanisms that aid in the interpretation of SEEBIC data. |
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Wos |
001006191600001 |
Publication Date |
2023-06-12 |
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Edition |
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ISSN |
2639-4979 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
1 |
Open Access |
OpenAccess |
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Notes |
The funding for this project was provided by European Research Council (ERC Consolidator Grant 815128, REALNANO). J.V. acknowledges the eBEAM project, which is supported by the European Union’s Horizon 2020 research and innovation program under grant agreement no. 101017720 (FET-Proactive EBEAM). L.M.L.-M. acknowledges funding from MCIN/AEI/10.13039/501100011033 (grant # PID2020-117779RB-I00). |
Approved |
Most recent IF: NA |
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Call Number |
EMAT @ emat @c:irua:197004 |
Serial |
8795 |
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Author |
Carrasco, S.; Orcajo, G.; Martínez, F.; Imaz, I.; Kavak, S.; Arenas-Esteban, D.; Maspoch, D.; Bals, S.; Calleja, G.; Horcajada, P. |
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Title |
Hf/porphyrin-based metal-organic framework PCN-224 for CO2 cycloaddition with epoxides |
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A1 Journal article |
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Year |
2023 |
Publication |
Materials Today Advances |
Abbreviated Journal |
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Volume |
19 |
Issue |
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Pages |
100390 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Herein, we describe for the first time the synthesis of the highly porous Hf-tetracarboxylate porphyrin-based metal-organic framework (MOF) (Hf)PCN-224(M) (M = H2, Co2+). (Hf)PCN-224(H2) was easily and efficiently prepared following a simple microwave-assisted procedure with good yields (56–67%; space-time yields: 1100–1270 kg m−3·day−1), high crystallinity and phase purity by using trifluoromethanesulfonic acid and benzoic acid as modulators in less than 30 min. By simply introducing a preliminary step (10 min), 5,10,15,20-(tetra-4-carboxyphenyl)porphyrin linker (TCPP) was quantitatively metalated with Co2+ without additional purification and/or time consuming protection/deprotection steps to further obtain (Hf)PCN-224(Co). (Hf)PCN-224(Co) was then tested as catalyst in CO2 cycloaddition reaction with different epoxides to yield cyclic carbonates, showing the best catalytic performance described to date compared to other PCNs, under mild conditions (1 bar CO2, room temperature, 18–24 h). Twelve epoxides were tested, obtaining from moderate to excellent conversions (35–96%). Moreover, this reaction was gram scaled-up (x50) without significant loss of yield to cyclic carbonates. (Hf)PCN-224(Co) maintained its integrity and crystallinity even after 8 consecutive runs, and poisoning was efficiently reverted by a simple thermal treatment (175 °C, 6 h), fully recovering the initial catalytic activity. |
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Wos |
001025764000001 |
Publication Date |
2023-06-19 |
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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 |
2590-0498 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
10 |
Times cited |
1 |
Open Access |
OpenAccess |
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Notes |
S.C. acknowledges the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie (MSCA-COFUND) grant agreement No 754382 (GOT Energy Talent). S.C. and P.H. acknowledge “Comunidad de Madrid” and European Regional Development Fund-FEDER 2014-2020-OE REACT-UE 1 for their financial support to VIRMOF-CM project associated to R&D projects in response to COVID-19. The authors acknowledge H2020-MSCA-ITN-2019 HeatNMof (ref. 860942), the M-ERA-NET C-MOF-cell (grant PCI2020-111998 funded by MCIN/AEI /10.13039/501100011033 and European Union NextGenerationEU/PRTR) project, and Retos Investigación MOFSEIDON (grant PID2019-104228RB-I00 funded by MCIN/AEI/10.13039/501100011033) project. This work has been also supported by the Regional Government of Madrid (Project ACES2030-CM, S2018/EMT-4319) and the Universidad Rey Juan Carlos IMPULSO Project (grant MATER M − 3000). S.K acknowledges the Flemish Fund for Scientific Research (FWO Vlaanderen) through a PhD research grant (1181122 N). |
Approved |
Most recent IF: 10; 2023 IF: NA |
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Call Number |
EMAT @ emat @c:irua:197198 |
Serial |
8800 |
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Permanent link to this record |
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Author |
Sa, J.; Hu, N.; Heyvaert, W.; Van Gordon, K.; Li, H.; Wang, L.; Bals, S.; Liz-Marzán, L.M.; Ni, W. |
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Title |
Spontaneous Chirality Evolved at the Au–Ag Interface in Plasmonic Nanorods |
Type |
A1 Journal article |
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Year |
2023 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem. Mater. |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Chiral ligands are considered a required ingredient during the synthesis of dissymmetric plasmonic metal nanocrystals. The mechanism behind the generation of chiral structures involves the formation of high Miller index chiral facets, induced by the adsorption of such chiral ligands. We found however that, chirality can also evolve spontaneously, without the involvement of any chiral ligands, during the co-deposition of Au and Ag on Au nanorods. When using a specific Au/Ag ratio, phase segregation of the two metals leads to an interface within the obtained AuAg shell, which can be exposed by removing the Ag component via oxidative etching. Although a close-to-racemic mixture of chiral Au nanorods with right and left handedness is found in solution, electron tomography analysis evidences left- and righthanded helicities, both at the Au-Ag interface and at the exposed surface of Au NRs after Ag etching. The helicity profile of the NRs indicates dominating inclination angles in a range from 30° to 60°. Single-particle optical characterization also reveals random handedness in the plasmonic response of individual nanorods. We hypothesize that, the origin of chirality is related with symmetry breaking during the co-deposition of Au and Ag, through an initial perturbation in a small region on the Au-Ag interface that eventually leads to chiral segregation throughout the nanocrystal. |
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Wos |
001052093300001 |
Publication Date |
2023-08-21 |
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ISSN |
0897-4756 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
8.6 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
The authors acknowledge the financial support from the National Natural Science Foundation of China (grant 22074102). LMLM acknowledges funding from 26 MCIN/AEI/10.13039/501100011033 and “ESF Investing in your future” (Grant PID2020- 117779RB-I00). This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 823717 – ESTEEM3.; Ministerio de Ciencia e Innovaci?n, PID2020-117779RB-I00 ; H2020 Research Infrastructures, 823717 ; European Social Fund, PID2020-117779RB-I00 ; National Natural Science Foundation of China, 22074102 ; |
Approved |
Most recent IF: 8.6; 2023 IF: 9.466 |
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Call Number |
EMAT @ emat @c:irua:198151 |
Serial |
8810 |
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Permanent link to this record |
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Author |
Filez, M.; Feng, J.-Y.; Minjauw, M.M.; Solano, E.; Poonkottil, N.; Van Daele, M.; Ramachandran, R.K.; Li, C.; Bals, S.; Poelman, H.; Detavernier, C.; Dendooven, J.; Filez, M.; Minjauw, M.; Solano, E.; Poonkottil, N.; Li, C.; Bals, S.; Dendooven, J. |
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Title |
Shuffling atomic layer deposition gas sequences to modulate bimetallic thin films and nanoparticle properties |
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A1 Journal article |
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Year |
2022 |
Publication |
Chemistry of materials |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Atomic layer deposition (ALD) typically employs metal precursors and co-reactant pulses to deposit thin films in a layer-by-layer fashion. While conventional ABAB-type ALD sequences implement only two functionalities, namely, a metal source and ligand exchange agent, additional functionalities have emerged, including etching and reduction agents. Herein, we construct gas-phase sequences-coined as ALD+-with complex-ities reaching beyond the classic ABAB-type ALD by freely combining multiple functionalities within irregular pulse schemes, e.g., ABCADC. The possibilities of such combinations are explored as a smart strategy to tailor bimetallic thin films and nanoparticle (NP) properties. By doing so, we demonstrate that bimetallic thin films can be tailored with target thickness and through the full compositional range, while the morphology can be flexibly modulated from thin films to NPs by shuI 1ing the pulse sequence. These complex pulse schemes are expected to be broadly applicable but are here explored for Pd-Ru bimetallic thin films and NPs. |
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000823205700001 |
Publication Date |
2022-06-29 |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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ISSN |
0897-4756; 1520-5002 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
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Times cited |
2 |
Open Access |
OpenAccess |
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Notes |
This research was funded by the Research Foundation, Flanders (FWO) , and the Special Research Fund BOF of Ghent University (GOA 01G01019) . M.F. and M.M.M. acknowledge the FWO for a postdoctoral research fellowship (1280621N) . N.P. acknowledges the European Union's Horizon 2020 research and innovation program under the Marie Skiodowska-Curie grant agreement no. 765378. For the GISAXS measurements, the author s received funding from the European Community's Transnational Access Program CALIPSOplus. E.S. acknowledges the Spanish project RTI2018-093996-B-C32 MICINN/FEDER funds. Air Liquide is acknowledged for supporting this research. The authors acknowledge SOLEIL for the provision of synchrotron radiation facilities and would like to thank Dr. Alessandro Coati for assistance in using beamline SiXS. The GIWAXS experiments were performed at NCD-SWEET beamline at ALBA Synchrotron with the collaboration of ALBA staff . |
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no |
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Call Number |
UA @ admin @ c:irua:189541 |
Serial |
8928 |
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Author |
Grünewald, L.; Chezganov, D.; De Meyer, R.; Orekhov, A.; Van Aert, S.; Bogaerts, A.; Bals, S.; Verbeeck, J. |
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|
Title |
In Situ Plasma Studies Using a Direct Current Microplasma in a Scanning Electron Microscope |
Type |
A1 Journal Article |
|
Year |
2024 |
Publication |
Advanced Materials Technologies |
Abbreviated Journal |
Adv Materials Technologies |
|
|
Volume |
|
Issue |
|
Pages |
|
|
|
Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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|
Abstract |
Microplasmas can be used for a wide range of technological applications and to improve the understanding of fundamental physics. Scanning electron microscopy, on the other hand, provides insights into the sample morphology and chemistry of materials from the mm‐ down to the nm‐scale. Combining both would provide direct insight into plasma‐sample interactions in real‐time and at high spatial resolution. Up till now, very few attempts in this direction have been made, and significant challenges remain. This work presents a stable direct current glow discharge microplasma setup built inside a scanning electron microscope. The experimental setup is capable of real‐time in situ imaging of the sample evolution during plasma operation and it demonstrates localized sputtering and sample oxidation. Further, the experimental parameters such as varying gas mixtures, electrode polarity, and field strength are explored and experimental<italic>V</italic>–<italic>I</italic>curves under various conditions are provided. These results demonstrate the capabilities of this setup in potential investigations of plasma physics, plasma‐surface interactions, and materials science and its practical applications. The presented setup shows the potential to have several technological applications, for example, to locally modify the sample surface (e.g., local oxidation and ion implantation for nanotechnology applications) on the µm‐scale. |
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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 |
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Editor |
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Language |
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Wos |
001168639900001 |
Publication Date |
2024-02-25 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
2365-709X |
ISBN |
|
Additional Links |
UA library record; WoS full record |
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|
Impact Factor |
6.8 |
Times cited |
|
Open Access |
OpenAccess |
|
|
Notes |
L.G., S.B., and J.V. acknowledge support from the iBOF-21-085 PERsist research fund. D.C., S.V.A., and J.V. acknowledge funding from a TOPBOF project of the University of Antwerp (FFB 170366). R.D.M., A.B., and J.V. acknowledge funding from the Methusalem project of the University of Antwerp (FFB 15001A, FFB 15001C). A.O. and J.V. acknowledge funding from the Research Foundation Flanders (FWO, Belgium) project SBO S000121N. |
Approved |
Most recent IF: 6.8; 2024 IF: NA |
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|
Call Number |
EMAT @ emat @c:irua:204363 |
Serial |
8995 |
|
Permanent link to this record |
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Author |
Vandemeulebroucke, D.; Batuk, M.; Hajizadeh, A.; Wastiaux, M.; Roussel, P.; Hadermann, J. |
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|
Title |
Incommensurate Modulations and Perovskite Growth in LaxSr2–xMnO4−δAffecting Solid Oxide Fuel Cell Conductivity |
Type |
A1 Journal Article |
|
Year |
2024 |
Publication |
Chemistry of Materials |
Abbreviated Journal |
Chem. Mater. |
|
|
Volume |
|
Issue |
|
Pages |
|
|
|
Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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|
Abstract |
Ruddlesden-Popper La????Sr2−????MnO4−???? materials are interesting symmetric solid oxide
fuel cell electrodes due to their good redox stability, mixed ionic and electronic conducting behavior and thermal expansion that matches well with common electrolytes. In reducing environments – as at a solid oxide fuel cell anode – the x = 0.5 member, i.e. La0.5Sr1.5MnO4−????, has a much higher total conductivity than compounds with a different La/Sr ratio, although all those compositions have the same K2NiF4-type I4/mmm structure. The origin for this conductivity difference is not yet known in literature. Now, a combination of in-situ and ex-situ 3D electron diffraction, high-resolution imaging, energy-dispersive X-ray analysis and electron energy-loss spectroscopy uncovered clear differences between x=0.25 and x=0.5 in the pristine structure, as well as in the transformations upon high-temperature reduction. In La0.5Sr1.5MnO4−????, Ruddlesden-Popper n=2 layer defects and an amorphous surface layer are present, but not in La0.25Sr1.75MnO4−????. After annealing at 700°C in 5% H2/Ar, La0.25Sr1.75MnO4−???? transforms to a tetragonal 2D incommensurately modulated structure with modulation vectors ⃗????1 = 0.2848(1) · (⃗????* +⃗????*) and ⃗????2 =0.2848(1) · (⃗????* – ⃗????*), whereas La0.5Sr1.5MnO4−???? only partially transforms to an orthorhombic 1D incommensurately modulated structure,
with ⃗???? = 0.318(2) · ⃗????*. Perovskite domains grow at the crystal edge at 700°C in 5%
H2 or vacuum, due to the higher La concentration on the surface compared to the bulk, which leads to a different thermodynamic equilibrium. Since it is known that a lower degree of oxygen vacancy ordering and a higher amount of perovskite blocks enhance oxygen mobility, those differences in defect structure and structural transformation upon reduction, might all contribute to the higher conductivity of La0.5Sr1.5MnO4−???? in solid oxide fuel cell anode conditions compared to other La/Sr ratios. |
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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 |
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Editor |
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Language |
English |
Wos |
001174840900001 |
Publication Date |
2024-02-20 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0897-4756 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
|
|
Impact Factor |
8.6 |
Times cited |
|
Open Access |
Not_Open_Access |
|
|
Notes |
Universiteit Antwerpen, BOF TOP 38689 ; Fonds Wetenschappelijk Onderzoek, I003218N ; European Commission NanED, 956099 ; |
Approved |
Most recent IF: 8.6; 2024 IF: 9.466 |
|
|
Call Number |
EMAT @ emat @c:irua:204354 |
Serial |
8997 |
|
Permanent link to this record |
|
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|
Author |
Chakraborty, J.; Chatterjee, A.; Molkens, K.; Nath, I.; Arenas Esteban, D.; Bourda, L.; Watson, G.; Liu, C.; Van Thourhout, D.; Bals, S.; Geiregat, P.; Van der Voort, P. |
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Title |
Decoding Excimer Formation in Covalent–Organic Frameworks Induced by Morphology and Ring Torsion |
Type |
A1 Journal Article |
|
Year |
2024 |
Publication |
Advanced Materials |
Abbreviated Journal |
Advanced Materials |
|
|
Volume |
|
Issue |
|
Pages |
|
|
|
Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
|
|
Abstract |
A thorough and quantitative understanding of the fate of excitons in covalent–organic frameworks (COFs) after photoexcitation is essential for their augmented optoelectronic and photocatalytic applications via precise structure tuning. The synthesis of a library of COFs having identical chemical backbone with impeded conjugation, but varied morphology and surface topography to study the effect of these physical properties on the photophysics of the materials is herein reported. The variation of crystallite size and surface topography substantified different aggregation pattern in the COFs, which leads to disparities in their photoexcitation and relaxation properties. Depending on aggregation, an inverse correlation between bulk luminescence decay time and exciton binding energy of the materials is perceived. Further transient absorption spectroscopic analysis confirms the presence of highly localized, immobile, Frenkel excitons (of diameter 0.3–0.5 nm) via an absence of annihilation at high density, most likely induced by structural torsion of the COF skeletons, which in turn preferentially relaxes via long‐lived (nanosecond to microsecond) excimer formation (in femtosecond scale) over direct emission. These insights underpin the importance of structural and topological design of COFs for their targeted use in photocatalysis. |
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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 |
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Editor |
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Language |
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Wos |
001206226700001 |
Publication Date |
2024-04-22 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0935-9648 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
|
|
Impact Factor |
29.4 |
Times cited |
|
Open Access |
|
|
|
Notes |
PVDV, JC, AC, and IN acknowledge the FWO-Vlaanderen for research grant G020521N and the research board of UGent (BOF) through a Concerted Research Action (GOA010-17). JC acknowledges UGent for BOF postdoctoral grant (2022.0032.01). AC acknowledges FWO- Vlaanderen for postdoctoral grant (12T7521N). KM, DVT and PG acknowledges FWO- Vlaanderen for research grant G0B2921N. SB and DAE acknowledge financial support from ERC Consolidator Grant Number 815128 REALNANO. CHL acknowledges China Scholarship Council doctoral grant (201908110280). PVDV acknowledges Hercules Project AUGE/17/07 for the UV VIS DRS spectrometer and UGent BASBOF BOF20/BAS/015 for the powder X-Ray Diffractometer. PG thanks UGent for support of the Core Facility NOLIMITS. |
Approved |
Most recent IF: 29.4; 2024 IF: 19.791 |
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|
Call Number |
EMAT @ emat @c:irua:205967 |
Serial |
9118 |
|
Permanent link to this record |
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Author |
Guerrero, R.M.; Lemir, I.D.; Carrasco, S.; Fernández-Ruiz, C.; Kavak, S.; Pizarro, P.; Serrano, D.P.; Bals, S.; Horcajada, P.; Pérez, Y. |
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Title |
Scaling-Up Microwave-Assisted Synthesis of Highly Defective Pd@UiO-66-NH2Catalysts for Selective Olefin Hydrogenation under Ambient Conditions |
Type |
A1 Journal Article |
|
Year |
2024 |
Publication |
ACS Applied Materials & Interfaces |
Abbreviated Journal |
ACS Appl. Mater. Interfaces |
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Volume |
|
Issue |
|
Pages |
|
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Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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|
Abstract |
The need to develop green and cost-effective industrial catalytic processes has led to growing interest in preparing more robust, efficient, and selective heterogeneous catalysts at a large scale. In this regard, microwave-assisted synthesis is a fast method for fabricating heterogeneous catalysts (including metal oxides, zeolites, metal–organic frameworks, and supported metal nanoparticles) with enhanced catalytic properties, enabling synthesis scale-up. Herein, the synthesis of nanosized UiO-66-NH2 was optimized via a microwave-assisted hydrothermal method to obtain defective matrices essential for the stabilization of metal nanoparticles, promoting catalytically active sites for hydrogenation reactions (760 kg·m–3·day–1 space time yield, STY). Then, this protocol was scaled up in a multimodal microwave reactor, reaching 86% yield (ca. 1 g, 1450 kg·m–3·day–1 STY) in only 30 min. Afterward, Pd nanoparticles were formed in situ decorating the nanoMOF by an effective and fast microwave-assisted hydrothermal method, resulting in the formation of Pd@UiO-66-NH2 composites. Both the localization and oxidation states of Pd nanoparticles (NPs) in the MOF were achieved using high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and X-ray photoelectron spectroscopy (XPS), respectively. The optimal composite, loaded with 1.7 wt % Pd, exhibited an extraordinary catalytic activity (>95% yield, 100% selectivity) under mild conditions (1 bar H2, 25 °C, 1 h reaction time), not only in the selective hydrogenation of a variety of single alkenes (1-hexene, 1-octene, 1-tridecene, cyclohexene, and tetraphenyl ethylene) but also in the conversion of a complex mixture of alkenes (i.e., 1-hexene, 1-tridecene, and anethole). The results showed a powerful interaction and synergy between the active phase (Pd NPs) and the catalytic porous scaffold (UiO-66-NH2), which are essential for the selectivity and recyclability. |
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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 |
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Editor |
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Language |
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Wos |
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Publication Date |
2024-04-26 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
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ISSN |
1944-8244 |
ISBN |
|
Additional Links |
|
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|
Impact Factor |
9.5 |
Times cited |
|
Open Access |
|
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|
Notes |
The authors gratefully acknowledge financial support from “Comunidad de Madrid” and European Regional Development Fund-FEDER through the project HUB MADRID+CIRCULAR; the State Research Agency (MCIN/AEI /10.13039/501100011033) through the grant with reference number CEX2019-000931-M received in the 2019 call for “Severo Ochoa Centres of Excellence” and “María de Maeztu Units of Excellence” of the State Programme for Knowledge Generation and Scientific and Technological Strengthening of the R&D&I System; and MICIU through the project “NAPOLION” (PID2022-139956OB-I00). S.K. acknowledges the Flemish Fund for Scientific Research (FWO Vlaanderen) through a PhD research grant (1181124N). |
Approved |
Most recent IF: 9.5; 2024 IF: 7.504 |
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|
Call Number |
EMAT @ emat @ |
Serial |
9126 |
|
Permanent link to this record |
|
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Author |
Chakraborty, J.; Chatterjee, A.; Molkens, K.; Nath, I.; Arenas Esteban, D.; Bourda, L.; Watson, G.; Liu, C.; Van Thourhout, D.; Bals, S.; Geiregat, P.; Van der Voort, P. |
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|
Title |
Decoding Excimer Formation in Covalent–Organic Frameworks Induced by Morphology and Ring Torsion |
Type |
A1 Journal Article |
|
Year |
2024 |
Publication |
Advanced Materials |
Abbreviated Journal |
Advanced Materials |
|
|
Volume |
|
Issue |
|
Pages |
|
|
|
Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
|
|
Abstract |
A thorough and quantitative understanding of the fate of excitons in covalent–organic frameworks (COFs) after photoexcitation is essential for their augmented optoelectronic and photocatalytic applications via precise structure tuning. The synthesis of a library of COFs having identical chemical backbone with impeded conjugation, but varied morphology and surface topography to study the effect of these physical properties on the photophysics of the materials is herein reported. The variation of crystallite size and surface topography substantified different aggregation pattern in the COFs, which leads to disparities in their photoexcitation and relaxation properties. Depending on aggregation, an inverse correlation between bulk luminescence decay time and exciton binding energy of the materials is perceived. Further transient absorption spectroscopic analysis confirms the presence of highly localized, immobile, Frenkel excitons (of diameter 0.3–0.5 nm) via an absence of annihilation at high density, most likely induced by structural torsion of the COF skeletons, which in turn preferentially relaxes via long‐lived (nanosecond to microsecond) excimer formation (in femtosecond scale) over direct emission. These insights underpin the importance of structural and topological design of COFs for their targeted use in photocatalysis. |
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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 |
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Editor |
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Language |
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Wos |
001206226700001 |
Publication Date |
2024-04-22 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0935-9648 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
|
|
Impact Factor |
29.4 |
Times cited |
|
Open Access |
|
|
|
Notes |
PVDV, JC, AC, and IN acknowledge the FWO-Vlaanderen for research grant G020521N and the research board of UGent (BOF) through a Concerted Research Action (GOA010-17). JC acknowledges UGent for BOF postdoctoral grant (2022.0032.01). AC acknowledges FWOVlaanderen for postdoctoral grant (12T7521N). KM, DVT and PG acknowledges FWOVlaanderen for research grant G0B2921N. SB and DAE acknowledge financial support from ERC Consolidator Grant Number 815128 REALNANO. CHL acknowledges China Scholarship Council doctoral grant (201908110280). PVDV acknowledges Hercules Project AUGE/17/07 for the UV VIS DRS spectrometer and UGent BASBOF BOF20/BAS/015 for the powder X-Ray Diffractometer. PG thanks UGent for support of the Core Facility NOLIMITS. |
Approved |
Most recent IF: 29.4; 2024 IF: 19.791 |
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Call Number |
EMAT @ emat @c:irua:205967 |
Serial |
9130 |
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Permanent link to this record |
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Author |
Arisnabarreta, N.; Hao, Y.; Jin, E.; Salame, A.; Muellen, K.; Robert, M.; Lazzaroni, R.; Van Aert, S.; Mali, K.S.; De Feyter, S. |
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Title |
Single-layered imine-linked porphyrin-based two-dimensional covalent organic frameworks targeting CO₂ reduction |
Type |
A1 Journal article |
|
Year |
2024 |
Publication |
Advanced energy materials |
Abbreviated Journal |
|
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|
Volume |
|
Issue |
|
Pages |
|
|
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
The reduction of carbon dioxide (CO2) using porphyrin-containing 2D covalent organic frameworks (2D-COFs) catalysts is widely explored nowadays. While these framework materials are normally fabricated as powders followed by their uncontrolled surface heterogenization or directly grown as thin films (thickness >200 nm), very little is known about the performance of substrate-supported single-layered (approximate to 0.5 nm thickness) 2D-COFs films (s2D-COFs) due to its highly challenging synthesis and characterization protocols. In this work, a fast and straightforward fabrication method of porphyrin-containing s2D-COFs is demonstrated, which allows their extensive high-resolution visualization via scanning tunneling microscopy (STM) in liquid conditions with the support of STM simulations. The as-prepared single-layered film is then employed as a cathode for the electrochemical reduction of CO2. Fe porphyrin-containing s2D-COF@graphite used as a single-layered heterogeneous catalyst provided moderate-to-high carbon monoxide selectivity (82%) and partial CO current density (5.1 mA cm(-2)). This work establishes the value of using single-layered films as heterogene ous catalysts and demonstrates the possibility of achieving high performance in CO2 reduction even with extremely low catalyst loadings. |
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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 |
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Editor |
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Language |
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Wos |
001177577200001 |
Publication Date |
2024-02-28 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
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ISSN |
1614-6832; 1614-6840 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
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Impact Factor |
27.8 |
Times cited |
|
Open Access |
|
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|
Notes |
N.A. acknowledges a postdoctoral fellowship from the Research Foundation- Flanders (FWO) via grant 12ZS623N. S.D.F. acknowledges support from FWO (G0A4120N, G0H2122N, G0A5U24N), KU Leuven Internal Funds (grants C14/18/06, C14/19/079, C14/23/090), European Union under the Horizon Europe grant 101046231 (FantastiCOF), and M-ERA.NET via FWO (G0K9822N). S.D.F., K.M., Y.H., R.L., and S.V.A. were thankful to the FWO and FNRS for the financial support through the EOS program (grant 30489208, 40007495). Research in Mons was also supported by the Belgian National Fund for Scientific Research (FRS-FNRS) within the Consortium des Équipements de Calcul Intensif- CÉCI, and by the Walloon Region (ZENOBE and LUCIA Tier-1 supercomputers). E.J. appreciated the support from the Alexander von Humboldt Foundation, the Max Planck Society, the FLAG-ERA Grant OPERA by DFG 437130745, the National Natural Science Foundation of China (22288101), and the 111 Project (B17020). Partial financial support to M.R. from the Institut Universitaire de France (IUF) was warmly thanked. |
Approved |
Most recent IF: 27.8; 2024 IF: 16.721 |
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Call Number |
UA @ admin @ c:irua:204856 |
Serial |
9172 |
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Permanent link to this record |
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Author |
Dadsetani, M.; Titantah, J.T.; Lamoen, D. |
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Title |
Ab initio calculation of the energy-loss near-edge structure of some carbon allotropes: comparison with n-diamond |
Type |
A1 Journal article |
|
Year |
2010 |
Publication |
Diamond and related materials |
Abbreviated Journal |
Diam Relat Mater |
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Volume |
19 |
Issue |
1 |
Pages |
73-77 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The energy-loss near-edge structure (ELNES) spectra of several carbon allotropes (non-hydrogenated and hydrogenated face-centered cubic (FCC) carbon, rhombohedral carbon, glitter, hexagonite and lonsdaleite) are calculated within the supercell-core-excited density functional theory approach. In particular an experimental ELNES spectrum of new diamond (n-diamond) [Konyashin et al., Diamond Relat. Mater. 10, (2001) 99102] is compared with the ELNES spectra of FCC carbon, rhombohedral carbon and the so-called glitter structure. Our calculations show that the ELNES spectrum considered in that publication cannot be that of FCC carbon. |
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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 |
Amsterdam |
Editor |
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Language |
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Wos |
000274234500013 |
Publication Date |
2009-11-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
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ISSN |
0925-9635; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.561 |
Times cited |
11 |
Open Access |
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|
Notes |
Goa; Esteem 026019 |
Approved |
Most recent IF: 2.561; 2010 IF: 1.825 |
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Call Number |
UA @ lucian @ c:irua:79444 |
Serial |
29 |
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Permanent link to this record |
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Author |
Schryvers, D.; Cao, S.; Tirry, W.; Idrissi, H.; Van Aert, S. |
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Title |
Advanced three-dimensional electron microscopy techniques in the quest for better structural and functional materials |
Type |
A1 Journal article |
|
Year |
2013 |
Publication |
Science and technology of advanced materials |
Abbreviated Journal |
Sci Technol Adv Mat |
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Volume |
14 |
Issue |
1 |
Pages |
014206-14213 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
After a short review of electron tomography techniques for materials science, this overview will cover some recent results on different shape memory and nanostructured metallic systems obtained by various three-dimensional (3D) electron imaging techniques. In binary NiTi, the 3D morphology and distribution of Ni4Ti3 precipitates are investigated by using FIB/SEM slice-and-view yielding 3D data stacks. Different quantification techniques will be presented including the principal ellipsoid for a given precipitate, shape classification following a Zingg scheme, particle distribution function, distance transform and water penetration. The latter is a novel approach to quantifying the expected matrix transformation in between the precipitates. The different samples investigated include a single crystal annealed with and without compression yielding layered and autocatalytic precipitation, respectively, and a polycrystal revealing different densities and sizes of the precipitates resulting in a multistage transformation process. Electron tomography was used to understand the interaction between focused ion beam-induced Frank loops and long dislocation structures in nanobeams of Al exhibiting special mechanical behaviour measured by on-chip deposition. Atomic resolution electron tomography is demonstrated on Ag nanoparticles in an Al matrix. |
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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 |
Sendai |
Editor |
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Language |
|
Wos |
000316463800008 |
Publication Date |
2013-03-13 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
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ISSN |
1468-6996;1878-5514; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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|
Impact Factor |
3.798 |
Times cited |
6 |
Open Access |
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|
|
Notes |
Fwo; Iap; Esteem |
Approved |
Most recent IF: 3.798; 2013 IF: 2.613 |
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Call Number |
UA @ lucian @ c:irua:107343 |
Serial |
77 |
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Permanent link to this record |
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Author |
Blumenau, A.T.; Jones, R.; Frauenheim, T.; Willems, B.; Lebedev, O.I.; Van Tendeloo, G.; Fisher, D.; Martineau, P.M. |
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Title |
Dislocations in diamond : dissociation into partials and their glide motion |
Type |
A1 Journal article |
|
Year |
2003 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
68 |
Issue |
1 |
Pages |
014115-14119 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The dissociation of 60degrees and screw dislocations in diamond is modeled in an approach combining isotropic elasticity theory with ab initio-based tight-binding total-energy calculations. Both dislocations are found to dissociate with a substantial lowering of their line energies. For the 60degrees dislocation, however, an energy barrier to dissociation is found. We investigate the core structure of a screw dislocation distinguishing “shuffle,” “mixed,” and “glide” cores. The latter is found to be the most stable undissociated screw dislocation. Further, the glide motion of 90degrees and 30degrees partials is discussed in terms of a process involving the thermal formation and subsequent migration of kinks along the dislocation line. The calculated activation barriers to dislocation motion show that the 30degrees partial is less mobile than the 90degrees partial. Finally, high-resolution electron microscopy is performed on high-temperature, high-pressure annealed natural brown diamond, allowing the core regions of 60degrees dislocations to be imaged. The majority of dislocations are found to be dissociated. However, in some cases, undissociated 60degrees dislocations were also observed. |
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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 |
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Editor |
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Language |
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Wos |
000184582900050 |
Publication Date |
2003-08-01 |
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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 |
0163-1829;1095-3795; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
39 |
Open Access |
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|
Notes |
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Approved |
Most recent IF: 3.836; 2003 IF: NA |
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Call Number |
UA @ lucian @ c:irua:103800 |
Serial |
734 |
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Permanent link to this record |
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Author |
Scalise, E.; Houssa, M.; Cinquanta, E.; Grazianetti, C.; van den Broek, B.; Pourtois, G.; Stesmans, A.; Fanciulli, M.; Molle, A. |
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Title |
Engineering the electronic properties of silicene by tuning the composition of MoX2 and GaX (X = S,Se,Te) chalchogenide templates |
Type |
A1 Journal article |
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Year |
2014 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
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Volume |
1 |
Issue |
1 |
Pages |
011010 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
By using first-principles simulations, we investigate the interaction of a 2D silicon layer with two classes of chalcogenide-layered compounds, namely MoX2 and GaX (X = S, Se, Te). A rather weak (van der Waals) interaction between the silicene layers and the chalcogenide layers is predicted. We found that the buckling of the silicene layer is correlated to the lattice mismatch between the silicene layer and the MoX2 or GaX template. The electronic properties of silicene on these different templates largely depend on the buckling of the silicene layer: highly buckled silicene on MoS2 is predicted to be metallic, while low buckled silicene on GaS and GaSe is predicted to be semi-metallic, with preserved Dirac cones at the K points. These results indicate new routes for artificially engineering silicene nanosheets, providing tailored electronic properties of this 2D layer on non-metallic substrates. These non-metallic templates also open the way to the possible integration of silicene in future nanoelectronic devices. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000353649900011 |
Publication Date |
2014-05-29 |
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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 |
2053-1583; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.937 |
Times cited |
49 |
Open Access |
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|
Notes |
|
Approved |
Most recent IF: 6.937; 2014 IF: NA |
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Call Number |
UA @ lucian @ c:irua:126032 |
Serial |
1048 |
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Permanent link to this record |
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Author |
Hamelet, S.; Casas-Cabanas, M.; Dupont, L.; Davoisne, C.; Tarascon, J.M.; Masquelier, C. |
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Title |
Existence of superstructures due to large amounts of Fe vacancies in the LiFePO4-type framework |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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Volume |
23 |
Issue |
1 |
Pages |
32-38 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
LiFePO4 has been under intense scrutiny over the past decade because it stands as an attractive positive electrode material for the next generation of Li-ion batteries to power electric vehicles and hybrid electric vehicles, hence the importance of its thermal behavior. The reactivity of LiFePO4 with air at moderate temperatures is shown to be dependent on its particle size. For nanosized materials, a progressive displacement of Fe from the core structure leading to a composite made of nanosize Fe2O3 and highly defective, oxidized LixFeyPO4 compositions, among which the “ideal” formula LiFe2/3PO4. Herein we report, from both temperature-controlled X-ray diffraction and electronic diffraction microscopy, that these off-stoichiometry olivine-type compounds show a defect ordering resulting in the formation of a superstructure. Such a finding shows striking similarities with the temperature-driven oxidation of fayalite Fe2SiO4 (another olivine) to structurally defective laihunite, reported in the literature three decades ago. |
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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 |
000285726900007 |
Publication Date |
2010-12-14 |
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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 |
0897-4756;1520-5002; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.466 |
Times cited |
30 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 9.466; 2011 IF: 7.286 |
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Call Number |
UA @ lucian @ c:irua:105605 |
Serial |
1130 |
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Permanent link to this record |
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Author |
Vagov, A.V.; Shanenko, A.A.; Milošević, M.V.; Axt, V.M.; Peeters, F.M. |
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Title |
Extended Ginzburg-Landau formalism : systematic expansion in small deviation from the critical temperature |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
85 |
Issue |
1 |
Pages |
014502-014502,17 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Based on the Gor'kov formalism for a clean s-wave superconductor, we develop an extended version of the single-band Ginzburg-Landau (GL) theory by means of a systematic expansion in the deviation from the critical temperature T(c), i.e., tau = 1 – T/T(c). We calculate different contributions to the order parameter and the magnetic field: the leading contributions (proportional to tau(1/2) in the order parameter and. t in the magnetic field) are controlled by the standard GL theory, while the next-to-leading terms (proportional to tau(3/2) in the gap and proportional to tau(2) in the magnetic field) constitute the extended GL (EGL) approach. We derive the free-energy functional for the extended formalism and the corresponding expression for the current density. To illustrate the usefulness of our formalism, we calculate, in a semianalytical form, the temperature-dependent correction to the GL parameter at which the surface energy becomes zero, and analytically, the temperature dependence of the thermodynamic critical field. We demonstrate that the EGL formalism is not just a mathematical extension to the theory: variations of both the gap and the thermodynamic critical field with temperature calculated within the EGL theory are found in very good agreement with the full BCS results down to low temperatures, which dramatically improves the applicability of the formalism compared to its standard predecessor. |
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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 |
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Editor |
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Language |
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Wos |
000298985100002 |
Publication Date |
2012-01-10 |
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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 |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
36 |
Open Access |
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Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). A. V. V. is grateful to V. Zalipaev for important comments. A. A. S. thanks W. Pogosov for helpful notes. Discussions with E. H. Brandt and A. Perali are appreciated. ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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Call Number |
UA @ lucian @ c:irua:96232 |
Serial |
1155 |
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Permanent link to this record |
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Author |
Savchenko, D.V.; Serdan, A.A.; Morozov, V.A.; Van Tendeloo, G.; Ionov, S.G. |
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Title |
Improvement of the oxidation stability and the mechanical properties of flexible graphite foil by boron oxide impregnation |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
New carbon materials |
Abbreviated Journal |
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Volume |
27 |
Issue |
1 |
Pages |
12-18 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Flexible graphite foil produced by rolling expanded graphite impregnated with boron oxide was analyzed by laser mass spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy and thermogravimetry. It was shown that the modification of the graphite foil by boron oxide increases the onset temperature of oxidation by ∼ 150 °C. Impregnation of less than 2 mass% boron oxide also increased the tensile strength of the materials. The observed improvement was attributed to the blocking of active sites by boron oxide, which is probably chemically bonded to the edges of graphene sheets in expanded graphite particles. |
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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 |
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Editor |
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Language |
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Wos |
000304742100002 |
Publication Date |
2012-03-21 |
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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 |
1872-5805; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
5 |
Open Access |
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|
Notes |
Iap |
Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:96958 |
Serial |
1569 |
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Permanent link to this record |
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Author |
de Witte, K.; Busuioc, A.M.; Meynen, V.; Mertens, M.; Bilba, N.; Van Tendeloo, G.; Cool, P.; Vansant, E.F. |
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Title |
Influence of the synthesis parameters of TiO2-SBA-15 materials on the adsorption and photodegradation of rhodamine-6G |
Type |
A1 Journal article |
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Year |
2008 |
Publication |
Microporous and mesoporous materials: zeolites, clays, carbons and related materials |
Abbreviated Journal |
Micropor Mesopor Mat |
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Volume |
110 |
Issue |
1 |
Pages |
100-110 |
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Keywords |
A1 Journal article; Laboratory of adsorption and catalysis (LADCA); Electron microscopy for materials research (EMAT) |
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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 |
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Editor |
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Language |
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Wos |
000254056200013 |
Publication Date |
2007-10-02 |
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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 |
1387-1811; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.615 |
Times cited |
54 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.615; 2008 IF: 2.555 |
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Call Number |
UA @ lucian @ c:irua:68280 |
Serial |
1654 |
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Permanent link to this record |
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Author |
Ignatova, V.A.; Möller, W.; Conard, T.; Vandervorst, W.; Gijbels, R. |
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Title |
Interpretation of TOF-SIMS depth profiles from ultrashallow high-k dielectric stacks assisted by hybrid collisional computer simulation |
Type |
A1 Journal article |
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Year |
2005 |
Publication |
Applied physics A : materials science & processing |
Abbreviated Journal |
Appl Phys A-Mater |
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Volume |
81 |
Issue |
1 |
Pages |
71-77 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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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 |
Heidelberg |
Editor |
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Language |
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Wos |
000228794000013 |
Publication Date |
2005-04-11 |
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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 |
0947-8396;1432-0630; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.455 |
Times cited |
4 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.455; 2005 IF: 1.990 |
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Call Number |
UA @ lucian @ c:irua:60085 |
Serial |
1711 |
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Permanent link to this record |
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Author |
Zha, G.-Q.; Covaci, L.; Peeters, F.M.; Zhou, S.-P. |
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Title |
Majorana fermion states and fractional flux periodicity in mesoscopic d-wave superconducting loops with spin-orbit interaction |
Type |
A1 Journal article |
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Year |
2014 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
90 |
Issue |
1 |
Pages |
014522 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We numerically investigate the spin-orbit (SO) coupling effect on the magnetic flux evolution of energy and supercurrent in mesoscopic d-wave superconducting loops by solving the spin-generalized Bogoliubov-de Gennes equations self-consistently. It is found that the energy spectrum splits when the SO interaction is involved and the Majorana zero mode can be realized in the [100] edges of square systems for an appropriate SO coupling strength. Superconducting phase transitions appear when the energy gap closes, accompanied by energy jumps between different energy parabolas in the ground state, which provides a possible mechanism to support fractional flux periodicity of supercurrent. Moreover, in the case of rectangular loops with SO coupling, the jumps of the ground-state energy gradually disappear by increasing the ratio of length to height of the sample, and a paramagnetic response with opposite direction of the screening current around zero flux value can occur in such systems. |
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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 |
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Editor |
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Language |
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Wos |
000341233800010 |
Publication Date |
2014-07-31 |
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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 |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
7 |
Open Access |
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Notes |
; This work was supported by National Natural Science Foundation of China under Grants No. 61371020 and No. 61271163, by Visiting Scholar Program of Shanghai Municipal Education Commission, by Innovation Program of Shanghai Municipal Education Commission under Grant No. 13YZ006, and by the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 3.836; 2014 IF: 3.736 |
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Call Number |
UA @ lucian @ c:irua:119266 |
Serial |
1938 |
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Permanent link to this record |
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Author |
Stevens, W.J.J.; Meynen, V.; Bruijn, E.; Lebedev, O.I.; Van Tendeloo, G.; Cool, P.; Vansant, E.F. |
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Title |
Mesoporous material formed by acidic hydrothermal assembly of silicalite-1 precursor nanoparticles in the absence of meso-templates |
Type |
A1 Journal article |
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Year |
2008 |
Publication |
Microporous and mesoporous materials: zeolites, clays, carbons and related materials |
Abbreviated Journal |
Micropor Mesopor Mat |
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Volume |
110 |
Issue |
1 |
Pages |
77-85 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
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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 |
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Editor |
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Language |
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Wos |
000254056200010 |
Publication Date |
2007-09-13 |
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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 |
1387-1811; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.615 |
Times cited |
21 |
Open Access |
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Notes |
Fwo; Crp; Inside-Pores |
Approved |
Most recent IF: 3.615; 2008 IF: 2.555 |
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Call Number |
UA @ lucian @ c:irua:68229 |
Serial |
1998 |
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Permanent link to this record |
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Author |
Cheng, J.P.; Zhang, X.B.; Ye, Y.; Tao, X.Y.; Liu, F.; Li, Y.; Van Tendeloo, G. |
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Title |
Natural mineral-marine manganese nodule as a novel catalyst for the synthesis of carbon nanotubes |
Type |
A1 Journal article |
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Year |
2006 |
Publication |
Journal of Wuhan University of Technology: materials science edition |
Abbreviated Journal |
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Volume |
21 |
Issue |
1 |
Pages |
29-31 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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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 |
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Editor |
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Language |
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Wos |
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Publication Date |
0000-00-00 |
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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 |
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ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:57740 |
Serial |
2286 |
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Permanent link to this record |
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Author |
Shanenko, A.A.; Croitoru, M.D.; Peeters, F.M. |
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Title |
Oscillations of the superconducting temperature induced by quantum well states in thin metallic films: numerical solution of the Bogoliubov-de Gennes equations |
Type |
A1 Journal article |
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Year |
2007 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
75 |
Issue |
1 |
Pages |
014519,1-9 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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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 |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000243894600126 |
Publication Date |
2007-01-17 |
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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 |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
85 |
Open Access |
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Notes |
Fwo-Vi; Bof-Top; Iap |
Approved |
Most recent IF: 3.836; 2007 IF: 3.172 |
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Call Number |
UA @ lucian @ c:irua:63749 |
Serial |
2535 |
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Permanent link to this record |
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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. |
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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 |
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Volume |
84 |
Issue |
1 |
Pages |
014429-014429,16 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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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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Address |
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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 |
000293247400008 |
Publication Date |
2011-07-28 |
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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 |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
47 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
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Call Number |
UA @ lucian @ c:irua:91770 |
Serial |
2588 |
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Permanent link to this record |
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Author |
Shanenko, A.A.; Croitoru, M.D. |
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Title |
Shape resonances in the superconducting order parameter of ultrathin nanowires |
Type |
A1 Journal article |
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Year |
2006 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
73 |
Issue |
1 |
Pages |
012510,1-4 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Electron microscopy for materials research (EMAT) |
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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 |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000235009000033 |
Publication Date |
2006-01-17 |
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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 |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
41 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.836; 2006 IF: 3.107 |
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Call Number |
UA @ lucian @ c:irua:56613 |
Serial |
2990 |
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Permanent link to this record |
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Author |
Fang, C.M.; van Huis, M.A.; Zandbergen, H.W. |
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Title |
Stability and structures of the CFCC-TmC phases : a first-principles study |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Computational materials science |
Abbreviated Journal |
Comp Mater Sci |
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Volume |
51 |
Issue |
1 |
Pages |
146-150 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The η-M6C, γ-M23C6, and π-M11C2 phases (M = Cr, Mn and Fe) have complex cubic lattices with lattice parameters of approximately 1.0 nm. They belong to the CFCC-TmC family (complex face-centered cubic transition metal carbides), display a rich variety of crystal structures, and play in important role in iron alloys and steels. Here we show that first-principles calculations predict high stability for the γ-M23C6 and η-M6C phases, and instability for the π-M11C2 phases, taking into account various compositional and structural possibilities. The calculations also show a wide variety in magnetic properties. The Cr-containing phases were found to be non-magnetic and the Fe-phases to be ferromagnetic, while the Mn-containing phases were found to be either ferrimagnetic or non-magnetic. Details of the local atomic structures, and the formation and stability of these precipitates in alloys are discussed. |
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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 |
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Editor |
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Language |
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Wos |
000296214300020 |
Publication Date |
2011-08-29 |
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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 |
0927-0256; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.292 |
Times cited |
18 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.292; 2012 IF: 1.878 |
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Call Number |
UA @ lucian @ c:irua:93277 |
Serial |
3119 |
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Permanent link to this record |