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Author | Dinger, J.; Friedrich, T.; Reimann, T.; Toepfer, J. | ||||
Title | NiMn₂O₄ revisited : temperature-dependent cation distribution from in situ neutron diffraction and thermopower studies | Type | A1 Journal article | ||
Year | 2023 | Publication | Journal of the American Ceramic Society | Abbreviated Journal | |
Volume | 106 | Issue | 3 | Pages | 1834-1847 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The cation distribution of the negative temperature coefficient (NTC) thermistor spinel NiMn2O4 was studied in the temperature range from 55 to 900 degrees C, using a combined in situ neutron diffraction and thermopower study. Rietveld refinements of in situ neutron diffraction data reveal a temperature dependence of the degree of inversion with an inversion parameter of 0.70(1) at 900 degrees C and 0.87(1) at 55 degrees C. Thermopower measurements were evaluated using a modified Heikes formula, and the [Mn4+]/[Mn3+] ratio on octahedral sites of the spinel structure was calculated considering spin and orbital degeneracy. The inversion degree and disproportionation parameter, determined independently as function of temperature, were used to calculate the cation distribution of NiMn2O4 in the whole temperature range. At high temperature, within the stability range of the spinel, the cation distribution is characterized by a moderate degree of inversion with a concentration of NiB2+${\mathrm{Ni}}\mathrm{B}< | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000880360600001 | Publication Date | 2022-10-21 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0002-7820 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 3.9 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 3.9; 2023 IF: 2.841 | |||
Call Number | UA @ admin @ c:irua:192087 | Serial | 7326 | ||
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Author | Christiansen, T.; Cotte, M.; de Nolf, W.; Mouro, E.; Reyes-Herrera, J.; De Meyer, S.; Vanmeert, F.; Salvado, N.; Gonzalez, V.; Lindelof, P.E.; Mortensen, K.; Ryholt, K.; Janssens, K.; Larsen, S. | ||||
Title | Insights into the composition of ancient Egyptian red and black inks on papyri achieved by synchrotron-based microanalyses | Type | A1 Journal article | ||
Year | 2020 | Publication | Proceedings Of The National Academy Of Sciences Of The United States Of America | Abbreviated Journal | P Natl Acad Sci Usa |
Volume | 117 | Issue | 45 | Pages | 27825-27835 |
Keywords | A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
Abstract | A hitherto unknown composition is highlighted in the red and black inks preserved on ancient Egyptian papyri from the Roman period (circa 100 to 200 CE). Synchrotron-based macro-X-ray fluo-rescence (XRF) mapping brings to light the presence of iron (Fe) and lead (Pb) compounds in the majority of the red inks inscribed on 12 papyrus fragments from the Tebtunis temple library. The iron-based compounds in the inks can be assigned to ocher, notably due to the colocalization of Fe with aluminum, and the detection of hematite (Fe2O3) by micro-X-ray diffraction. Using the same techniques together with micro-Fourier transform infrared spectroscopy, Pb is shown to be associated with fatty acid phosphate, sulfate, chloride, and carboxylate ions. Moreover, microXRF maps reveal a peculiar distribution and colocalization of Pb, phosphorus (P), and sulfur (S), which are present at the micrometric scale resembling diffused “coffee rings” surrounding the ocher particles imbedded in the red letters, and at the submicrometric scale concentrated in the papyrus cell walls. A similar Pb, P, and S composition was found in three black inks, suggesting that the same lead components were employed in the manufacture of carbon-based inks. Bearing in mind that pigments such as red lead (Pb3O4) and lead white (hydrocerussite [Pb-3(CO3)(2)(OH)(2)] and/or cerussite [PbCO3]) were not detected, the results presented here suggest that the lead compound in the ink was used as a drier rather than as a pigment. Accordingly, the study calls for a reassessment of the composition of lead-based components in ancient Mediterranean pigments. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000590753400016 | Publication Date | 2020-10-27 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0027-8424; 1091-6490 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 11.1 | Times cited | Open Access | ||
Notes | Approved | Most recent IF: 11.1; 2020 IF: 9.661 | |||
Call Number | UA @ admin @ c:irua:174323 | Serial | 8107 | ||
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Author | Geerlings, N.M.J.; Karman, C.; Trashin, S.; As, K.S.; Kienhuis, M.V.M.; Hidalgo-Martinez, S.; Vasquez-Cardenas, D.; Boschker, H.T.S.; De Wael, K.; Middelburg, J.J.; Polerecky, L.; Meysman, F.J.R. | ||||
Title | Division of labor and growth during electrical cooperation in multicellular cable bacteria | Type | A1 Journal article | ||
Year | 2020 | Publication | Proceedings Of The National Academy Of Sciences Of The United States Of America | Abbreviated Journal | P Natl Acad Sci Usa |
Volume | 117 | Issue | 10 | Pages | 5478-5485 |
Keywords | A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
Abstract | Multicellularity is a key evolutionary innovation, leading to coordinated activity and resource sharing among cells, which generally occurs via the physical exchange of chemical compounds. However, filamentous cable bacteria display a unique metabolism in which redox transformations in distant cells are coupled via long-distance electron transport rather than an exchange of chemicals. This challenges our understanding of organismal functioning, as the link among electron transfer, metabolism, energy conservation, and filament growth in cable bacteria remains enigmatic. Here, we show that cells within individual filaments of cable bacteria display a remarkable dichotomy in biosynthesis that coincides with redox zonation. Nanoscale secondary ion mass spectrometry combined with 13 C (bicarbonate and propionate) and 15 N-ammonia isotope labeling reveals that cells performing sulfide oxidation in deeper anoxic horizons have a high assimilation rate, whereas cells performing oxygen reduction in the oxic zone show very little or no label uptake. Accordingly, oxygen reduction appears to merely function as a mechanism to quickly dispense of electrons with little to no energy conservation, while biosynthesis and growth are restricted to sulfide-respiring cells. Still, cells can immediately switch roles when redox conditions change, and show no differentiation, which suggests that the “community service” performed by the cells in the oxic zone is only temporary. Overall, our data reveal a division of labor and electrical cooperation among cells that has not been seen previously in multicellular organisms. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000519530400054 | Publication Date | 2020-02-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0027-8424; 1091-6490 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 11.1 | Times cited | 6 | Open Access | |
Notes | ; We thank Arnold van Dijk for helping with the GasBench isotope ratio mass spectrometry analysis. N.M.J.G. is the recipient of a Ph.D. scholarship for teachers from the Netherlands Organisation for Scientific Research (NWO) in the Netherlands (grant 023.005.049). K.S.A. received financial support from the Olaf Schuiling fund. F.J.R.M. was financially supported by the Research Foundation Flanders (FWO) via grant G043119N, and the Netherlands Organization for Scientific Research (VICI grant 016.VICI.170.072). J.J.M. was supported by the Ministry of Education via the Netherlands Earth System Science Centre. The NanoSIMS facility was partly supported by an NWO large infrastructure subsidy to J.J.M. (175.010.2009.011). ; | Approved | Most recent IF: 11.1; 2020 IF: 9.661 | ||
Call Number | UA @ admin @ c:irua:166452 | Serial | 6487 | ||
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Author | Liao, Z.; Gauquelin, N.; Green, R.J.; Müller-Caspary, K.; Lobato, I.; Li, L.; Van Aert, S.; Verbeeck, J.; Huijben, M.; Grisolia, M.N.; Rouco, V.; El Hage, R.; Villegas, J.E.; Mercy, A.; Bibes, M.; Ghosez, P.; Sawatzky, G.A.; Rijnders, G.; Koster, G. | ||||
Title | Metal–insulator-transition engineering by modulation tilt-control in perovskite nickelates for room temperature optical switching | Type | A1 Journal article | ||
Year | 2018 | Publication | America | Abbreviated Journal | P Natl Acad Sci Usa |
Volume | 115 | Issue | 38 | Pages | 9515-9520 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | In transition metal perovskites ABO3 the physical properties are largely driven by the rotations of the BO6 octahedra, which can be tuned in thin films through strain and dimensionality control. However, both approaches have fundamental and practical limitations due to discrete and indirect variations in bond angles, bond lengths and film symmetry by using commercially available substrates. Here, we introduce modulation tilt control as a new approach to tune the ground state of perovskite oxide thin films by acting explicitly on the oxygen octahedra rotation modes, i.e. directly on the bond angles. By intercalating the prototype SmNiO3 target material with a tilt-control layer, we cause the system to change the natural amplitude of a given rotation mode without affecting the interactions. In contrast to strain and dimensionality engineering, our method enables a continuous fine-tuning of the materials properties. This is achieved through two independent adjustable parameters: the nature of the tilt-control material (through its symmetry, elastic constants and oxygen rotation angles) and the relative thicknesses of the target and tilt-control materials. As a result, a magnetic and electronic phase diagram can be obtained, normally only accessible by A-site element substitution, within the single SmNiO3 compound. With this unique approach, we successfully adjusted the metal-insulator transition (MIT) to room temperature to fulfill the desired conditions for optical switching applications. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000447224900057 | Publication Date | 2018-09-05 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0027-8424 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 9.661 | Times cited | 50 | Open Access | OpenAccess |
Notes | We would like to acknowledge Prof. Z. Zhong for stimulated discussion. M.H., G.K. and G.R. acknowledge funding from DESCO program of the Dutch Foundation for Fundamental Research on Matter (FOM) with financial support from the Netherlands Organization for Scientific Research (NWO). This work was funded by the European Union Council under the 7th Framework Program (FP7) grant nr NMP3-LA-2010-246102 IFOX. J.V., S.V.A, N.G. and K.M.C. acknowledge funding from FWO projects G.0044.13N, G.0374.13N, G. 0368.15N, and G.0369.15N. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. N.G. acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant 278510 VORTEX. N.G. and J.V. acknowledge financial support from the European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure Initiative (Reference No. 312483- ESTEEM2). The Canadian work was supported by NSERC and the Max Planck-UBC Centre for Quantum Materials. Some experiments for this work were performed at the Canadian Light Source, which is funded by the Canada Foundation for Innovation, NSERC, the National Research Council of Canada, the Canadian Institutes of Health Research, the Government of Saskatchewan, Western Economic Diversification Canada, and the University of Saskatchewan. MB acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC CoG grant MINT #615759. A.M. and Ph.G. were supported by the ARC project AIMED and F.R.S-FNRS PDR project HiT4FiT and acknowledge access to Céci computing facilities funded by F.R.S-FNRS (Grant No 2.5020.1), Tier-1 supercomputer of the Fédération Wallonie-Bruxelles funded by the Walloon Region (Grant No 1117545) and HPC resources from the PRACE project Megapasta. | Approved | Most recent IF: 9.661 | ||
Call Number | EMAT @ emat @c:irua:154784UA @ admin @ c:irua:154784 | Serial | 5059 | ||
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Author | Kumar, J.; Eraña, H.; López-Martínez, E.; Claes, N.; Martín, V.F.; Solís, D.M.; Bals, S.; Cortajarena, A.L.; Castilla, J.; Liz-Marzán, L.M. | ||||
Title | Detection of amyloid fibrils in Parkinson’s disease using plasmonic chirality | Type | A1 Journal article | ||
Year | 2018 | Publication | Proceedings of the National Academy of Sciences of the United States of America | Abbreviated Journal | P Natl Acad Sci Usa |
Volume | 115 | Issue | 115 | Pages | 3225-3230 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Amyloid fibrils, which are closely associated with various neurodegenerative diseases, are the final products in many protein aggregation pathways. The identification of fibrils at low concentration is, therefore, pivotal in disease diagnosis and development of therapeutic strategies. We report a methodology for the specific identification of amyloid fibrils using chiroptical effects in plasmonic nanoparticles. The formation of amyloid fibrils based on α-synuclein was probed using gold nanorods, which showed no apparent interaction with monomeric proteins but effective adsorption onto fibril structures via noncovalent interactions. The amyloid structure drives a helical nanorod arrangement, resulting in intense optical activity at the surface plasmon resonance wavelengths. This sensing technique was successfully applied to human brain homogenates of patients affected by Parkinson’s disease, wherein protein fibrils related to the disease were identified through chiral signals from Au nanorods in the visible and near IR, whereas healthy brain samples did not exhibit any meaningful optical activity. The technique was additionally extended to the specific detection of infectious amyloids formed by prion proteins, thereby confirming the wide potential of the technique. The intense chiral response driven by strong dipolar coupling in helical Au nanorod arrangements allowed us to detect amyloid fibrils down to nanomolar concentrations. |
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Language | Wos | 000428382400032 | Publication Date | 2018-03-12 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0027-8424 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 9.661 | Times cited | 187 | Open Access | OpenAccess |
Notes | We thank Prof. Dr. J.-P. Timmermans and the Antwerp Centre of Advanced Microscopy for providing access to the Tecnai G2 Spirit BioTWIN TEM. We also thank the Basque Biobank (Basque Foundation for Health Innovation and Research, BIOEF) for providing us with Parkinson’s disease-affected brain samples. J.K. acknowledges financial support from the European Commission under Marie Sklodowska-Curie Program H2020- MSCA-IF-2015708321. S.B. and A.L.C. acknowledge European Research Council Grants 335078 COLOURATOM and 648071 ProNANO. S.B. and L.M.L.-M. acknowledge funding from European Commission Grant EUSMI 731019. A.L.C., J.C., and L.M.L.-M. acknowledge funding from Spanish Ministry of Economy and Competitiveness (MINECO) Grants MAT2013-46101- R, AGL2015-65046-C2-1-R, and BIO2016-77367-C2-1-R. (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:restricted); saraecas; ECASSara; | Approved | Most recent IF: 9.661 | ||
Call Number | EMAT @ emat @c:irua:150355UA @ admin @ c:irua:150355 | Serial | 4918 | ||
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Author | Xia, C.; Winckelmans, N.; Prins, P.T.; Bals, S.; Gerritsen, H.C.; de Mello Donegá, C. | ||||
Title | Near-Infrared-Emitting CuInS2/ZnS Dot-in-Rod Colloidal Heteronanorods by Seeded Growth | Type | A1 Journal article | ||
Year | 2018 | Publication | Journal of the American Chemical Society | Abbreviated Journal | J Am Chem Soc |
Volume | 140 | Issue | 140 | Pages | 5755-5763 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Synthesis protocols for anisotropic CuInX2 (X = S, Se, Te)-based heteronanocrystals (HNCs) are scarce due to the difficulty in balancing the reactivities of multiple precursors and the high solid-state diffusion rates of the cations involved in the CuInX2 lattice. In this work, we report a multistep seeded growth synthesis protocol that yields colloidal wurtzite CuInS2/ZnS dot core/rod shell HNCs with photoluminescence in the NIR (∼800 nm). The wurtzite CuInS2 NCs used as seeds are obtained by topotactic partial Cu+ for In3+ cation exchange in template Cu2–xS NCs. The seed NCs are injected in a hot solution of zinc oleate and hexadecylamine in octadecene, 20 s after the injection of sulfur in octadecene. This results in heteroepitaxial growth of wurtzite ZnS primarily on the Sulfur-terminated polar facet of the CuInS2 seed NCs, the other facets being overcoated only by a thin (∼1 monolayer) shell. The fast (∼21 nm/min) asymmetric axial growth of the nanorod proceeds by addition of [ZnS] monomer units, so that the polarity of the terminal (002) facet is preserved throughout the growth. The delayed injection of the CuInS2 seed NCs is crucial to allow the concentration of [ZnS] monomers to build up, thereby maximizing the anisotropic heteroepitaxial growth rates while minimizing the rates of competing processes (etching, cation exchange, alloying). Nevertheless, a mild etching still occurred, likely prior to the onset of heteroepitaxial overgrowth, shrinking the core size from 5.5 to ∼4 nm. The insights provided by this work open up new possibilities in designing multifunctional Cu-chalcogenide based colloidal heteronanocrystals. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000431600000016 | Publication Date | 2018-03-29 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0002-7863 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.858 | Times cited | 43 | Open Access | OpenAccess |
Notes | Chenghui Xia acknowledges China Scholarship Council (CSC) for financial support (NO. 201406330055). S.B and N.W. acknowledge funding from the European Research Council (Starting Grant No. COLOURATOMS 335078). C.d.M.D. acknowledge financial support from the division of Chemical Sciences (CW) of The Netherlands Organization for Scientific Research (NWO) under Grant Number ECHO.712.014.001. The authors thank Xiaobin Xie and Da Wang for some TEM measurements, Donglong Fu for XRD measurements, Christina H. M. van Oversteeg for ICP-OES measurements, and Chun-Che Lin for suggestions regarding the synthesis. ECAS_Sara (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); | Approved | Most recent IF: 13.858 | ||
Call Number | EMAT @ emat @c:irua:150362UA @ admin @ c:irua:150362 | Serial | 4917 | ||
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Author | van der Stam, W.; Geuchies, J.J.; Altantzis, T.; van den Bos, K.H.W.; Meeldijk, J.D.; Van Aert, S.; Bals, S.; Vanmaekelbergh, D.; de Mello Donega, C. | ||||
Title | Highly Emissive Divalent-Ion-Doped Colloidal CsPb1–xMxBr3Perovskite Nanocrystals through Cation Exchange | Type | A1 Journal article | ||
Year | 2017 | Publication | Journal of the American Chemical Society | Abbreviated Journal | J Am Chem Soc |
Volume | 139 | Issue | 139 | Pages | 4087-4097 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Colloidal CsPbX3 (X = Br, Cl, and I) perovskite nanocrystals (NCs) have emerged as promising phosphors and solar cell materials due to their remarkable optoelectronic properties. These properties can be tailored by not only controlling the size and shape of the NCs but also postsynthetic composition tuning through topotactic anion exchange. In contrast, property control by cation exchange is still underdeveloped for colloidal CsPbX3 NCs. Here, we present a method that allows partial cation exchange in colloidal CsPbBr3 NCs, whereby Pb2+ is exchanged for several isovalent cations, resulting in doped CsPb1−xMxBr3 NCs (M= Sn2+, Cd2+, and Zn2+; 0 < x ≤ 0.1), with preservation of the original NC shape. The size of the parent NCs is also preserved in the product NCs, apart from a small (few %) contraction of the unit cells upon incorporation of the guest cations. The partial Pb2+ for M2+ exchange leads to a blue-shift of the optical spectra, while maintaining the high photoluminescence quantum yields (>50%), sharp absorption features, and narrow emission of the parent CsPbBr3 NCs. The blue-shift in the optical spectra is attributed to the lattice contraction that accompanies the Pb2+ for M2+ cation exchange and is observed to scale linearly with the lattice contraction. This work opens up new possibilities to engineer the properties of halide perovskite NCs, which to date are demonstrated to be the only known system where cation and anion exchange reactions can be sequentially combined while preserving the original NC shape, resulting in compositionally diverse perovskite NCs. |
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000397477700027 | Publication Date | 2017-03-10 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0002-7863 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.858 | Times cited | 535 | Open Access | OpenAccess |
Notes | W.v.d.S. and C.d.M.D. acknowledge financial support from the division of Chemical Sciences (CW) of The Netherlands Organization for Scientific Research (NWO) under grant number ECHO.712.012.001. J.J.G. and D.V. acknowledge financial support from the Debye Graduate program. S.B. acknowledges financial support from the European Research Council (ERC Starting Grant # 335078-COLOURATOMS). K.H.W.v.d.B., S.B., S.V.A. and T.A. acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0374.13N, G.0368.15N, G.0369.15N), a Ph.D. grant to K.H.W.v.d.B, and a postdoctoral research grant to T.A. (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); ECAS_Sara | Approved | Most recent IF: 13.858 | ||
Call Number | EMAT @ emat @ c:irua:141754UA @ admin @ c:irua:141754 | Serial | 4482 | ||
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Author | Sánchez-Iglesias, A.; Winckelmans, N.; Altantzis, T.; Bals, S.; Grzelczak, M.; Liz-Marzán, L.M. | ||||
Title | High-Yield Seeded Growth of Monodisperse Pentatwinned Gold Nanoparticles through Thermally Induced Seed Twinning | Type | A1 Journal article | ||
Year | 2016 | Publication | Journal of the American Chemical Society | Abbreviated Journal | J Am Chem Soc |
Volume | 139 | Issue | 139 | Pages | 107-110 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | We show here that thermal treatment of small seeds results in extensive twinning and a subsequent drastic yield improvement (>85%) in the formation of pentatwinned nanoparticles, with pre-selected morphology (nanorods, bipyramids and decahedra) and aspect ratio. The “quality” of the seeds thus defines the yield of the obtained nanoparticles, which in the case of nanorods avoids the need for additives such as Ag+ ions. This modified seeded growth method also improves reproducibility, as the seeds can be stored for extended periods of time without compromising the quality of the final nanoparticles. Additionally, minor modification of the seeds with Pd allows their localization within the final particles, which opens new avenues toward mechanistic studies. All together, these results represent a paradigm shift in anisotropic gold nanoparticle synthesis. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000392036900025 | Publication Date | 2016-12-29 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 0002-7863 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.858 | Times cited | 267 | Open Access | OpenAccess |
Notes | Financial support is acknowledged from the European Research Council through ERC Advanced Grant Plasmaquo and the ERC Starting Grant COLOURATOM. T.A. acknowledges financial support from the Research Foundation Flanders (FWO, Belgium) through a postdoctoral grant. (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); ECAS_Sara | Approved | Most recent IF: 13.858 | ||
Call Number | EMAT @ emat @ c:irua:139018UA @ admin @ c:irua:139018 | Serial | 4339 | ||
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Author | Niu, H.; Pitcher, M.J.; Corkett, A.J.; Ling, S.; Mandal, P.; Zanella, M.; Dawson, K.; Stamenov, P.; Batuk, D.; Abakumov, A.M.; Bull, C.L.; Smith, R.I.; Murray, C.A.; Day, S.J.; Slater, B.; Cora, F.; Claridge, J.B.; Rosseinsky, M.J. | ||||
Title | Room Temperature Magnetically Ordered Polar Corundum GaFeO3 Displaying Magnetoelectric Coupling | Type | A1 Journal article | ||
Year | 2017 | Publication | Journal of the American Chemical Society | Abbreviated Journal | J Am Chem Soc |
Volume | 139 | Issue | 4 | Pages | 1520-1531 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The polar corundum structure type offers a route to new room temperature multiferroic materials, as the partial LiNbO3-type cation ordering that breaks inversion symmetry may be combined with long-range magnetic ordering of high spin d(5) cations above room temperature in the AFeO(3) system. We report the synthesis of a polar corundum GaFeO3 by a high-pressure, high-temperature route and demonstrate that its polarity arises from partial LiNbO3 -type cation ordering by complementary use of neutron, X-ray, and electron diffraction methods. In situ neutron diffraction shows that the polar corundum forms directly from AlFeO3-type GaFeO3 under the synthesis conditions. The A(3+)/Fe3+ cations are shown to be more ordered in polar corundum GaFeO3 than in isostructural ScFeO3. This is explained by DFT calculations which indicate that the extent of ordering is dependent on the configurational entropy available to each system at the very different synthesis temperatures required to form their corundum structures. Polar corundum GaFeO3 exhibits weak ferromagnetism at room temperature that arises from its Fe2O3-like magnetic ordering, which persists to a temperature of 408 K. We demonstrate that the polarity and magnetization are coupled in this system with a measured linear magnetoelectric coupling coefficient of 0.057 ps/m. Such coupling is a prerequisite for potential applications of polar corundum materials in multiferroic/magnetoelectric devices. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000393355600034 | Publication Date | 2016-12-25 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 0002-7863 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.858 | Times cited | 12 | Open Access | OpenAccess |
Notes | This work was funded by the EPSRC under EP/N004884. We thank the STFC for provision of beam time at ISIS and Diamond Light Source. We thank the Materials Chemistry Consortium (EPSRC, EP/L000202) for access to computer time on the ARCHER UK National Supercomputing Service (http://www.archer.ac.uk). A.M.A. is grateful to the Russian Science Foundation (Grant 14-13-00680) for financial support. MJ.R is a Royal Society Research Professor. We wish to thank Dr. Ming Li (University of Nottingham, UK) for helpful discussion and advice. Original data is available at the University of Liverpool's DataCat repository at DOI: 10.17638/datacat.liverpool.ac.uk/235. The supporting crystallographic information file may also be obtained from FIZ Karlsruhe, 76344 Eggenstein-Leopoldshafen, Germany (e-mail: crysdata@fiz-karlsruhe.de), on quoting the deposition number CSD-432419. | Approved | Most recent IF: 13.858 | ||
Call Number | EMAT @ emat @c:irua:147507 | Serial | 4777 | ||
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Author | Polavarapu, L.; Zanaga, D.; Altantzis, T.; Rodal-Cedeira, S.; Pastoriza-Santos, I.; Pérez-Juste, J.; Bals, S.; Liz-Marzán, L.M. | ||||
Title | Galvanic Replacement Coupled to Seeded Growth as a Route for Shape-Controlled Synthesis of Plasmonic Nanorattles | Type | A1 Journal article | ||
Year | 2016 | Publication | Journal of the American Chemical Society | Abbreviated Journal | J Am Chem Soc |
Volume | 138 | Issue | 138 | Pages | 11453-11456 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Shape-controlled synthesis of metal nanoparticles (NPs) requires mechanistic understanding toward the development of modern nanoscience and nanotechnology. We demonstrate here an unconventional shape transformation of Au@Ag core−shell NPs (nanorods and nanocubes) into octahedral nanorattles via roomtemperature galvanic replacement coupled with seeded growth. The corresponding morphological and chemical transformations were investigated in three dimensions, using state-of-the-art X-ray energy-dispersive spectroscopy (XEDS) tomography. The addition of a reducing agent (ascorbic acid) plays a key role in this unconventional mechanistic path, in which galvanic replacement is found to dominate initially when the shell is made of Ag, while seeded growth suppresses transmetalation when a composition of Au:Ag (∼60:40) is reached in the shell, as revealed by quantitative XEDS tomography. This work not only opens new avenues toward the shape control of hollow NPs beyond the morphology of sacrificial templates, but also expands our understanding of chemical transformations in nanoscale galvanic replacement reactions. The XEDS electron tomography study presented here can be generally applied to investigate a wide range of nanoscale morphological and chemical transformations. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000383410700008 | Publication Date | 2016-09-14 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0002-7863 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.858 | Times cited | 75 | Open Access | OpenAccess |
Notes | This work has been funded by the European Research Council (ERC Advanced Grant No. 267867- PLASMAQUO, ERC Starting Grant No. 335078-COLOURATOMS) and Spanish MINECO (Grants MAT2013-45168-R and MAT2013-46101-R); ECAS_Sara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); | Approved | Most recent IF: 13.858 | ||
Call Number | EMAT @ emat @ c:irua:137123 | Serial | 4329 | ||
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Author | Bladt, E.; van Dijk-Moes, R.J.A.; Peters, J.; Montanarella, F.; de Mello Donega, C.; Vanmaekelbergh, D.; Bals, S. | ||||
Title | Atomic Structure of Wurtzite CdSe (Core)/CdS (Giant Shell) Nanobullets Related to Epitaxy and Growth | Type | A1 Journal article | ||
Year | 2016 | Publication | Journal of the American Chemical Society | Abbreviated Journal | J Am Chem Soc |
Volume | 138 | Issue | 138 | Pages | 14288-14293 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Hetero-nanocrystals consisting of a CdSe core and a giant CdS shell have shown remarkable optical properties which are promising for applications in opto-electrical devices. Since these properties sensitively depend on the size and shape, a morphological characterization is of high interest. Here, we present a High Angle Annular Dark Field Scanning Transmission Electron Microscopy (HAADF-STEM) study of CdSe (core) / CdS (giant shell) hetero-nanocrystals. Electron tomography reveals that the nanocrystals have a bullet shape, either ending in a tip or a small dip, and that the CdSe core is positioned closer to the tip (or dip) than to the hexagonal base. Based on a high resolution HAADF-STEM study, we were able to determine all the surface facets. We present a heuristic model for the different growth stages of the CdS crystal around the CdSe core. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000387095000026 | Publication Date | 2016-11-02 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0002-7863 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.858 | Times cited | 28 | Open Access | OpenAccess |
Notes | S.B. acknowledges financial support from European Research Council (ERC Starting Grant #335078-COLOURATOMS). D.V. wishes to acknowledge the Dutch Foundation for Fundamental Research on Matter (FOM) in the programme ‘Designing Dirac Carriers in Semiconductor Superstructures’. E.B. gratefully acknowledges financial support by the Flemish Fund for Scientific Research (FWO Vlaanderen).; ECAS_Sara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); | Approved | Most recent IF: 13.858 | ||
Call Number | EMAT @ emat @ c:irua:138251 | Serial | 4325 | ||
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Author | Yang, Z.; Altantzis, T.; Zanaga, D.; Bals, S.; Van Tendeloo, G.; Pileni, M.-P. | ||||
Title | Supracrystalline Colloidal Eggs: Epitaxial Growth and Freestanding Three-Dimensional Supracrystals in Nanoscaled Colloidosomes | Type | A1 Journal article | ||
Year | 2016 | Publication | Journal of the American Chemical Society | Abbreviated Journal | J Am Chem Soc |
Volume | 138 | Issue | 138 | Pages | 3493-3500 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The concept of template-confined chemical reactions allows the synthesis of complex molecules that would hardly be producible through conventional method. This idea was developed to produce high quality nanocrystals more than 20 years ago. However, template-mediated assembly of colloidal nanocrystals is still at an elementary level, not only because of the limited templates suitable for colloidal assemblies, but also because of the poor control over the assembly of nanocrystals within a confined space. Here, we report the design of a new system called “supracrystalline colloidal eggs” formed by controlled assembly of nanocrystals into complex colloidal supracrystals through superlattice-matched epitaxial overgrowth along the existing colloidosomes. Then, with this concept, we extend the supracrystalline growth to lattice-mismatched binary nanocrystal superlattices, in order to reach anisotropic superlattice growths, yielding freestanding binary nanocrystal supracrystals that could not be produced previously. | ||||
Address | CEA/IRAMIS , CEA Saclay F-91191 Gif-sur-Yvette, France | ||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | English | Wos | 000372477700034 | Publication Date | 2016-02-24 |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0002-7863 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.858 | Times cited | 57 | Open Access | OpenAccess |
Notes | The research leading to these results has been supported by an Advanced Grant of the European Research Council under Grant 267129. The authors appreciate financial support by the European Union under the Framework 7 program under a contract for an Integrated Infrastructure Initiative (Reference No. 312483 ESTEEM2). The authors thank Dr. P. A. Albouy for the SAXS measurement.; esteem2_ta | Approved | Most recent IF: 13.858 | ||
Call Number | c:irua:131923 c:irua:131923 | Serial | 4018 | ||
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Author | Broers, F.T.H.; Janssens, K.; Weker, J.N.; Webb, S.M.; Mehta, A.; Meirer, F.; Keune, K. | ||||
Title | Two pathways for the degradation of orpiment pigment (As₂S₃) found in paintings | Type | A1 Journal article | ||
Year | 2023 | Publication | Journal of the American Chemical Society | Abbreviated Journal | |
Volume | 145 | Issue | 16 | Pages | 8847-8859 |
Keywords | A1 Journal article; Antwerp X-ray Imaging and Spectroscopy (AXIS) | ||||
Abstract | Paintings are complex objects containing many different chemical compounds that can react over time. The degradation of arsenic sulfide pigments causes optical changes in paintings. The main degradation product was thought to be white arsenolite (As2O3), but previous research also showed the abundant presence of As(V) species. In this study, we investigate the influence of the presence of a medium on the degradation mechanism of orpiment (As2S3) using synchrotron radiation (SR)-based tomographic transmission X-ray microscopy, SR-based micro-X-ray fluorescence, and Xray absorption near edge structure spectroscopy. Upon direct illumination of dry orpiment powder using UV-visible light, only the formation of As2O3 was observed. When As2S3 was surrounded by a medium and illuminated, As2O3 was only observed in the area directly exposed to light, while As(V) degradation species were found elsewhere in the medium. Without accelerated artificial light aging, As(V)(aq) species are formed and migrate throughout the medium within weeks after preparation. In both scenarios, the As(V) species form via intermediate As(III)(aq) species and the presence of a medium is necessary. As(V)(aq) species can react with available cations to form insoluble metal arsenates, which induces stress within the paint layers (leading to, e.g., cracks and delamination) or can lead to a visual change of the image of the painting. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000974346900001 | Publication Date | 2023-04-14 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0002-7863 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 15 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 15; 2023 IF: 13.858 | |||
Call Number | UA @ admin @ c:irua:196762 | Serial | 8948 | ||
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Author | Lopez-Garcia, C.; Canossa, S.; Hadermann, J.; Gorni, G.; Oropeza, F.E.; de la Pena O'Shea, V.A.; Iglesias, M.; Monge, M.A.; Gutierrez-Puebla, E.; Gandara, F. | ||||
Title | Heterometallic molecular complexes act as messenger building units to encode desired metal-atom combinations to multivariate metal-organic frameworks | Type | A1 Journal article | ||
Year | 2022 | Publication | Journal of the American Chemical Society | Abbreviated Journal | J Am Chem Soc |
Volume | 144 | Issue | 36 | Pages | 16262-16266 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | A novel synthetic approach is described for the targeted preparation of multivariate metal-organic frameworks (MTV-MOFs) with specific combinations of metal elements. This methodology is based on the use of molecular complexes that already comprise desired metal-atom combinations, as building units for the MTV-MOF synthesis. These units are transformed into the MOF structural constituents through a ligand/linker exchange process that involves structural modifications while preserving their origina l l y encoded atomic combination. Thus, through the use of heterometalli c ring-shaped molecules combining gallium and nickel or cobalt, we have obtained MOFs with identical combinations of the metal elements, now incorporated in the rod-shaped secondary building unit, as confirmed with a combination of X-ray and electron diffraction, electron microscopy, and X-ray absorption spectroscopy techniques. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000841435900001 | Publication Date | 2022-08-12 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0002-7863 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 15 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 15 | |||
Call Number | UA @ admin @ c:irua:190023 | Serial | 7169 | ||
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Author | Feng, X.; Jena, H.S.; Krishnaraj, C.; Arenas-Esteban, D.; Leus, K.; Wang, G.; Sun, J.; Rüscher, M.; Timoshenko, J.; Roldan Cuenya, B.; Bals, S.; Voort, P.V.D. | ||||
Title | Creation of Exclusive Artificial Cluster Defects by Selective Metal Removal in the (Zn, Zr) Mixed-Metal UiO-66 | Type | A1 Journal article | ||
Year | 2021 | Publication | Journal Of The American Chemical Society | Abbreviated Journal | J Am Chem Soc |
Volume | Issue | Pages | jacs.1c05357 | ||
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | The differentiation between missing linker defects and missing cluster defects in MOFs is difficult, thereby limiting the ability to correlate materials properties to a specific type of defects. Herein, we present a novel and easy synthesis strategy for the creation of solely “missing cluster defects” by preparing mixed-metal (Zn, Zr)-UiO-66 followed by a gentle acid wash to remove the Zn nodes. The resulting material has the reo UiO-66 structure, typical for well-defined missing cluster defects. The missing clusters are thoroughly characterized, including low-pressure Ar-sorption, iDPCSTEM at a low dose (1.5 pA), and XANES/EXAFS analysis. We show that the missing cluster UiO-66 has a negligible number of missing linkers. We show the performance of the missing cluster UiO-66 in CO2 sorption and heterogeneous catalysis. |
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000730569500001 | Publication Date | 2021-12-07 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0002-7863 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.858 | Times cited | 29 | Open Access | OpenAccess |
Notes | Agentschap Innoveren en Ondernemen, HBC.2019.0110 HBC.2021.0254 ; Universiteit Gent; Fonds Wetenschappelijk Onderzoek, 665501 ; Dalian University of Technology; China Scholarship Council, 201507565009 ; National Natural Science Foundation of China, 22101039 ; H2020 European Research Council, 815128 REALNANO ; sygmaSB | Approved | Most recent IF: 13.858 | ||
Call Number | EMAT @ emat @c:irua:183951 | Serial | 6833 | ||
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Author | Gonzalez-Nelson, A.; Mula, S.; Simenas, M.; Balciunas, S.; Altenhof, A.R.; Vojvodin, C.S.; Canossa, S.; Banys, J.; Schurko, R.W.; Coudert, F.-X.; van der Veen, M.A. | ||||
Title | Emergence of coupled rotor dynamics in metal-organic frameworks via tuned steric interactions | Type | A1 Journal article | ||
Year | 2021 | Publication | Journal Of The American Chemical Society | Abbreviated Journal | J Am Chem Soc |
Volume | 143 | Issue | 31 | Pages | 12053-12062 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The organic components in metal-organic frameworks (MOFs) are unique: they are embedded in a crystalline lattice, yet, as they are separated from each other by tunable free space, a large variety of dynamic behavior can emerge. These rotational dynamics of the organic linkers are especially important due to their influence over properties such as gas adsorption and kinetics of guest release. To fully exploit linker rotation, such as in the form of molecular machines, it is necessary to engineer correlated linker dynamics to achieve their cooperative functional motion. Here, we show that for MIL-53, a topology with closely spaced rotors, the phenylene functionalization allows researchers to tune the rotors' steric environment, shifting linker rotation from completely static to rapid motions at frequencies above 100 MHz. For steric interactions that start to inhibit independent rotor motion, we identify for the first time the emergence of coupled rotation modes in linker dynamics. These findings pave the way for function-specific engineering of gear-like cooperative motion in MOFs. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000684581100022 | Publication Date | 2021-07-29 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0002-7863 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.858 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 13.858 | |||
Call Number | UA @ admin @ c:irua:180504 | Serial | 6867 | ||
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Author | Imran, M.; Peng, L.; Pianetti, A.; Pinchetti, V.; Ramade, J.; Zito, J.; Di Stasio, F.; Buha, J.; Toso, S.; Song, J.; Infante, I.; Bals, S.; Brovelli, S.; Manna, L. | ||||
Title | Halide perovskite-lead chalcohalide nanocrystal heterostructures | Type | A1 Journal article | ||
Year | 2021 | Publication | Journal Of The American Chemical Society | Abbreviated Journal | J Am Chem Soc |
Volume | 143 | Issue | 3 | Pages | 1435-1446 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | We report the synthesis of colloidal CsPbX3-Pb4S3Br2 (X = Cl, Br, I) nanocrystal heterostructures, providing an example of a sharp and atomically resolved epitaxial interface between a metal halide perovskite and a non-perovskite lattice. The CsPbBr3-Pb4S3Br2 nanocrystals are prepared by a two-step direct synthesis using preformed subnanometer CsPbBr3 clusters. Density functional theory calculations indicate the creation of a quasi-type II alignment at the heterointerface as well as the formation of localized trap states, promoting ultrafast separation of photogenerated excitons and carrier trapping, as confirmed by spectroscopic experiments. Postsynthesis reaction with either Cl- or I- ions delivers the corresponding CsPbCI3-Pb4S3Br2 and CsPbI3-Pb4S3Br2 heterostructures, thus enabling anion exchange only in the perovskite domain. An increased structural rigidity is conferred to the perovskite lattice when it is interfaced with the chalcohalide lattice. This is attested by the improved stability of the metastable gamma phase (or “black” phase) of CsPbI3 in the CsPbI3-Pb4S3Br2 heterostructure. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000614064400024 | Publication Date | 2021-01-15 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0002-7863 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.858 | Times cited | 54 | Open Access | OpenAccess |
Notes | This work was performed on the Dutch national e-infrastructure with the support of SURF Cooperative. L.P. and J.S. are thankful for the support by the National Key R&D Program of China (2018YFC0910600) and the National Natural Science Foundation of China (61775145). F.D.S. and S.B. acknowledge support by the European Research Council via the ERC-StG “NANOLED” (851794) and the ERC-Cog “REALNANO” (815128). The authors acknowledge financial support from the European Commission under the Horizon 2020 Programme through Grant Agreement No. 731019 (EUSMI). S.B., A.P., and V.P. gratefully acknowledge the financial support from the Italian Ministry of University and Research (MIUR) through grant “Dipartimenti di Eccellenza2017 Materials For Energy”.; sygma | Approved | Most recent IF: 13.858 | ||
Call Number | UA @ admin @ c:irua:176584 | Serial | 6726 | ||
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Author | Toso, S.; Akkerman, Q.A.; Martin-Garcia, B.; Prato, M.; Zito, J.; Infante, I.; Dang, Z.; Moliterni, A.; Giannini, C.; Bladt, E.; Lobato, I.; Ramade, J.; Bals, S.; Buha, J.; Spirito, D.; Mugnaioli, E.; Gemmi, M.; Manna, L. | ||||
Title | Nanocrystals of lead chalcohalides : a series of kinetically trapped metastable nanostructures | Type | A1 Journal article | ||
Year | 2020 | Publication | Journal Of The American Chemical Society | Abbreviated Journal | J Am Chem Soc |
Volume | 142 | Issue | 22 | Pages | 10198-10211 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | We report the colloidal synthesis of a series of surfactant-stabilized lead chalcohalide nanocrystals. Our work is mainly focused on Pb4S3Br2, a chalcohalide phase unknown to date that does not belong to the ambient-pressure PbS-PbBr2 phase diagram. The Pb4S3Br2 nanocrystals herein feature a remarkably narrow size distribution (with a size dispersion as low as 5%), a good size tunability (from 7 to similar to 30 nm), an indirect bandgap, photoconductivity (responsivity = 4 +/- 1 mA/W), and stability for months in air. A crystal structure is proposed for this new material by combining the information from 3D electron diffraction and electron tomography of a single nanocrystal, X-ray powder diffraction, and density functional theory calculations. Such a structure is closely related to that of the recently discovered high-pressure chalcohalide Pb4S3I2 phase, and indeed we were able to extend our synthesis scheme to Pb4S3I2 colloidal nanocrystals, whose structure matches the one that has been published for the bulk. Finally, we could also prepare nanocrystals of Pb3S2Cl2, which proved to be a structural analogue of the recently reported bulk Pb3Se2Br2 phase. It is remarkable that one high-pressure structure (for Pb4S3I2) and two metastable structures that had not yet been reported (for Pb4S3Br2 and Pb3S2Cl2) can be prepared on the nanoscale by wet-chemical approaches. This highlights the important role of colloidal chemistry in the discovery of new materials and motivates further exploration into metal chalcohalide nanocrystals. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000538526500035 | Publication Date | 2020-05-06 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0002-7863 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 15 | Times cited | 32 | Open Access | OpenAccess |
Notes | ; We would like to thank Dr. A. Toma for the access to the IIT clean room facilities' SEM/FIB and evaporators, the Smart Materials group (IIT) for the access to the ATR-FTIR equipment, S. Marras for the support during XRPD measurements, G. Pugliese for help with the TGA measurements, M. Campolucci for help with the experiments on NC growth kinetics, S. Lauciello for help with the SEM-EDX analyses, and D. Baranov and R. Brescia for the helpful discussions. We also acknowledge funding from the Programme for Research and Innovation Horizon 2020 (2014-2020) under the Marie Sklodowska-Curie Grant Agreement COMPASS No. 691185. I.I. acknowledges the Dutch NWO for financial support under the Vidi scheme (Grant No. 723.013.002). S.B. acknowledges support by means of the ERC Consolidator Grant No. 815128 REALNANO. E. M. and M.G acknowledge the Regione Toscana for funding the purchase of the Timepix detector through the FELIX project (Por CREO FESR 2014-2020 action). ; sygma | Approved | Most recent IF: 15; 2020 IF: 13.858 | ||
Call Number | UA @ admin @ c:irua:170218 | Serial | 6566 | ||
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Author | Zaikina, J.V.; Batuk, M.; Abakumov, A.M.; Navrotsky, A.; Kauziarich, S.M. | ||||
Title | Facile synthesis of Ba1-xKxFe2As2 superconductors via hydride route | Type | A1 Journal article | ||
Year | 2014 | Publication | Journal of the American Chemical Society | Abbreviated Journal | J Am Chem Soc |
Volume | 136 | Issue | 48 | Pages | 16932-16939 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | We have developed a fast, easy, and scalable synthesis method for Ba1xKxFe2As2 (0 ≤ x ≤ 1) superconductors using hydrides BaH2 and KH as a source of barium and potassium metals. Synthesis from hydrides provides better mixing and easier handling of the starting materials, consequently leading to faster reactions and/or lower synthesis temperatures. The reducing atmosphere provided by the evolved hydrogen facilitates preparation of oxygen-free powders. By a combination of methods we have shown that Ba1xKxFe2As2 obtained via hydride route has the same characteristics as when it is prepared by traditional solid-state synthesis. Refinement from synchrotron powder X-ray diffraction data confirms a linear dependence of unit cell parameters upon K content as well as the tetragonal to orthorhombic transition at low temperatures for compositions with x < 0.2. Magnetic measurements revealed dome-like dependence of superconducting transition temperature Tc upon K content with a maximum of 38 K for x close to 0.4. Electron diffraction and high-resolution high-angle annular dark-field scanning transmission electron microscopy indicates an absence of Ba/K ordering, while local inhomogeneity in the Ba/K distribution takes place at a scale of several angstroms along [110] crystallographic direction. | ||||
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Publisher | Place of Publication | Washington, D.C. | Editor | ||
Language | Wos | 000345883900040 | Publication Date | 2014-11-11 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0002-7863;1520-5126; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.858 | Times cited | 13 | Open Access | |
Notes | Approved | Most recent IF: 13.858; 2014 IF: 12.113 | |||
Call Number | UA @ lucian @ c:irua:121331 | Serial | 1169 | ||
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Author | Pittarello, L.; Mckibbin, S.; Yamaguchi, A.; Ji, G.; Schryvers, D.; Debaille, V.; Claeys, P. | ||||
Title | Two generations of exsolution lamellae in pyroxene from Asuka 09545 : Clues to the thermal evolution of silicates in mesosiderite | Type | A1 Journal article | ||
Year | 2019 | Publication | The American mineralogist | Abbreviated Journal | Am Mineral |
Volume | 104 | Issue | 11 | Pages | 1663-1672 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Mesosiderite meteorites consist of a mixture of crustal basaltic or gabbroic material and metal. Their formation process is still debated due to their unexpected combination of crust and core materials, possibly derived from the same planetesimal parent body, and lacking an intervening mantle component. Mesosiderites have experienced an extremely slow cooling rate from ca. 550 degrees C, as recorded in the metal (0.25-0.5 degrees C/Ma). Here we present a detailed investigation of exsolution features in pyroxene from the Antarctic mesosiderite Asuka (A) 09545. Geothermobarometry calculations, lattice parameters, lamellae orientation, and the presence of clinoenstatite as the host were used in an attempt to constrain the evolution of pyroxene from 1150 to 570 degrees C and the formation of two generations of exsolution lamellae. After pigeonite crystallization at ca. 1150 degrees C, the first exsolution process generated the thick augite lamellae along (100) in the temperature interval 1000-900 degrees C. By further cooling, a second order of exsolution lamellae formed within augite along (001), consisting of monoclinic low-Ca pyroxene, equilibrated in the temperature range 900-800 degrees C. The last process, occurring in the 600-500 degrees C temperature range, was likely the inversion of high to low pigeonite in the host crystal, lacking evidence for nucleation of orthopyroxene. The formation of two generations of exsolution lamellae, as well as of likely metastable pigeonite, suggest non-equilibrium conditions. Cooling was sufficiently slow to allow the formation of the lamellae, their preservation, and the transition from high to low pigeonite. In addition, the preservation of such fine-grained lamellae limits long-lasting, impact reheating to a peak temperature lower than 570 degrees C. These features, including the presence of monoclinic low-Ca pyroxene as the host, are reported in only a few mesosiderites. This suggests a possibly different origin and thermal history from most mesosiderites and that the crystallography (i.e., space group) of low-Ca pyroxene could be used as parameter to distinguish mesosiderite populations based on their cooling history. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000494707400014 | Publication Date | 2019-08-22 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-004x | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.021 | Times cited | Open Access | ||
Notes | Approved | Most recent IF: 2.021 | |||
Call Number | UA @ admin @ c:irua:164645 | Serial | 6331 | ||
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Author | Bonroy, J.; Volckaert, M.; Seuntjens, P. | ||||
Title | Rapid automated measurement system for simultaneous determination of effective air-filled porosity and soil gas diffusivity | Type | A1 Journal article | ||
Year | 2011 | Publication | Soil Science Society of America journal | Abbreviated Journal | |
Volume | 75 | Issue | 2 | Pages | 408-417 |
Keywords | A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) | ||||
Abstract | The effective air-filled porosity and the gas diffusion coefficient are important soil parameters determining the success of soil bioremediation projects such as (bio)venting and (bio)sparging methods in combination with soil vapor extraction. We have developed a new method to sequentially measure the effective air-filled porosity and the soil gas diffusion coefficient of a soil sample. During the purging of the sample, a fast and accurate measurement of the effective air-filled porosity can be obtained. The subsequent diffusion measurement does not require a zero-O(2) concentration in the soil sample. The procedure further allows the calculation of the soil gas diffusion coefficient before an equilibrium O(2) concentration has been reached. The results are obtained by combining the data of the inlet and outlet compartment in a single equation. A stable reading is reached when the results for the inlet and outlet compartment coincide with the results from the combined equation. The analysis time is reduced by 89 to 96% compared with methods that run until an equilibrium concentration has been reached. Moreover, combining data from inlet and outlet compartments increases the accuracy of the diffusivity measurement by a factor of two compared with previous methods. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000288827000009 | Publication Date | 2012-09-19 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0361-5995 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | Times cited | Open Access | |||
Notes | Approved | no | |||
Call Number | UA @ admin @ c:irua:113062 | Serial | 8453 | ||
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Author | Matulis, A.; Peeters, F.M. | ||||
Title | Analogy between one-dimensional chain models and graphene | Type | A1 Journal article | ||
Year | 2009 | Publication | American journal of physics | Abbreviated Journal | Am J Phys |
Volume | 77 | Issue | 7 | Pages | 595-601 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | The electron and hole spectrum in single and bilayer graphene is derived from known one-dimensional models, and the relation between the spectrum and symmetry of the lattice is shown. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | New York, N.Y. | Editor | ||
Language | Wos | 000266976000003 | Publication Date | 2009-06-11 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0002-9505; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.069 | Times cited | 11 | Open Access | |
Notes | Approved | Most recent IF: 1.069; 2009 IF: 0.779 | |||
Call Number | UA @ lucian @ c:irua:77381 | Serial | 97 | ||
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Author | Ibrahim, I.S.; Peeters, F.M. | ||||
Title | The magnetic Kronig-Penney model | Type | A1 Journal article | ||
Year | 1995 | Publication | American journal of physics | Abbreviated Journal | Am J Phys |
Volume | 63 | Issue | Pages | 171-173 | |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | |||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | New York, N.Y. | Editor | ||
Language | Wos | A1995QC79100024 | Publication Date | 2005-03-31 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0002-9505; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 0.956 | Times cited | 21 | Open Access | |
Notes | Approved | no | |||
Call Number | UA @ lucian @ c:irua:12200 | Serial | 1883 | ||
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Author | Zhang, S.; Sahin, H.; Torun, E.; Peeters, F.; Martien, D.; DaPron, T.; Dilley, N.; Newman, N. | ||||
Title | Fundamental mechanisms responsible for the temperature coefficient of resonant frequency in microwave dielectric ceramics | Type | A1 Journal article | ||
Year | 2017 | Publication | Journal of the American Ceramic Society | Abbreviated Journal | J Am Ceram Soc |
Volume | 100 | Issue | 100 | Pages | 1508-1516 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | The temperature coefficient of resonant frequency ((f)) of a microwave resonator is determined by three materials parameters according to the following equation: (f)=-(1/2 (epsilon) + 1/2 + (L)), where (L), (epsilon), and are defined as the linear temperature coefficients of the lattice constant, dielectric constant, and magnetic permeability, respectively. We have experimentally determined each of these parameters for Ba(Zn1/3Ta2/3)O-3, 0.8 at.% Ni-doped Ba(Zn1/3Ta2/3)O-3, and Ba(Ni1/3Ta2/3)O-3 ceramics. These results, in combination with density functional theory calculations, have allowed us to develop a much improved understanding of the fundamental physical mechanisms responsible for the temperature coefficient of resonant frequency, (f). | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Columbus, Ohio | Editor | ||
Language | Wos | 000399610800034 | Publication Date | 2017-02-14 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0002-7820 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.841 | Times cited | 6 | Open Access | |
Notes | ; ; | Approved | Most recent IF: 2.841 | ||
Call Number | UA @ lucian @ c:irua:143682 | Serial | 4597 | ||
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Author | Abakumov, A.M.; Hadermann, J.; Van Tendeloo, G.; Antipov, E.V. | ||||
Title | Chemistry and structure of anion-deficient perovskites with translational interfaces | Type | A1 Journal article | ||
Year | 2008 | Publication | Journal of the American Ceramic Society | Abbreviated Journal | J Am Ceram Soc |
Volume | 91 | Issue | 6 | Pages | 1807-1813 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | |||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Columbus, Ohio | Editor | ||
Language | Wos | 000256410700010 | Publication Date | 2008-04-29 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0002-7820;1551-2916; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.841 | Times cited | 39 | Open Access | |
Notes | Approved | Most recent IF: 2.841; 2008 IF: 2.101 | |||
Call Number | UA @ lucian @ c:irua:70088 | Serial | 355 | ||
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Author | Fang, P.a.; Gu, H.; Wang, P.l.; Van Landuyt, J.; Vleugels, J.; Van der Biest, O.; | ||||
Title | Effect of powder coating on stabilizer distribution in CeO2-stabilized ZrO2 ceramics | Type | A1 Journal article | ||
Year | 2005 | Publication | Journal of the American Ceramic Society | Abbreviated Journal | J Am Ceram Soc |
Volume | 88 | Issue | 7 | Pages | 1929-1934 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The phase and microstructure relationship of 12 mol% CeO2-stabilized ZrO2 ceramics prepared from coated powder was investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersed Xray spectroscopy (EDS). As compared with the sample prepared with co-precipitated method, which exhibited a similar grain size distribution, the EDS analysis revealed that the powder coating induced a wide distribution of CeO2 solubility, which decreases monotonically with the increase of grain size. This variation of stabilizer content from grain to grain rendered many large grains in the monoclinic phase. Stronger cerium segregation to grain boundaries was observed between large grains, which often form thin amorphous films there. The inhomogeneous; CeO2 distribution keeps more tetragonal ZrO2 grains close to the phase boundary to facilitate the transforming toughness. Addition of an Al2O3 precursor in coated powders effectively raises the overall CeO2 stabilizer content in the grains and preserves more transformable tetragonal phase in the microstructure, which further enhanced the fracture toughness. The dependence of CeO2 solubility on grain size may be explained in a simple coating-controlled diffusion and growth process that deserves further investigation. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Columbus, Ohio | Editor | ||
Language | Wos | 000230128100040 | Publication Date | 2005-06-23 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0002-7820;1551-2916; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.841 | Times cited | 11 | Open Access | |
Notes | Approved | Most recent IF: 2.841; 2005 IF: 1.586 | |||
Call Number | UA @ lucian @ c:irua:103156 | Serial | 830 | ||
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Author | Bals, S.; Verbeeck, J.; Van Tendeloo, G.; Liu, Y.-L.; Grivel, J.-C. | ||||
Title | Quantitative electron microscopy of (Bi,Pb)2Sr2Ca2Cu3O10+\delta/Ag multifilament tapes during initial stages of annealing | Type | A1 Journal article | ||
Year | 2005 | Publication | Journal of the American Ceramic Society | Abbreviated Journal | J Am Ceram Soc |
Volume | 88 | Issue | 2 | Pages | 431-436 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The microstructural and compositional evolution during initial annealing of a superconducting (Bi,Pb)(2)Sr2Ca2Cu3O10+delta/Ag tape is studied using quantitative transmission electron microscopy. Special attention is devoted to the occurrence of Pb-rich liquids, which are crucial for the Bi2Sr2CaCu2O8+delta to (Bi,Pb)(2)Sr2Ca2Cu3O10+delta transformation. Ca and/or Pb-rich (Bi,Pb)(2)Sr2CaCu2O8+delta grains dissolve into a liquid, which reacts with Ca-rich phases to increase the liquid's Ca-content. This leads to (Bi,Pb)(2)Sr2Ca2Cu3O10+delta formation. Apparently, a Ca/Sr ratio of around I is sufficient to keep (Bi,Pb)(2)Sr2Ca2Cu3O10+delta nucleation going. It is confirmed that Ag particles are transported from the Ag-sheath into the oxide core by the liquid and not by mechanical treatment of the tape. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Columbus, Ohio | Editor | ||
Language | Wos | 000227510200030 | Publication Date | 2005-02-16 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0002-7820;1551-2916; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.841 | Times cited | 1 | Open Access | |
Notes | Approved | Most recent IF: 2.841; 2005 IF: 1.586 | |||
Call Number | UA @ lucian @ c:irua:54876UA @ admin @ c:irua:54876 | Serial | 2754 | ||
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Author | MacLennan, D.; Trentelman, K.; Szafran, Y.; Woollett, A.T.; Delaney, J.K.; Janssens, K.; Dik, J. | ||||
Title | Rembrandt's An Old Man in Military Costume : combining hyperspectral and MA-XRF imaging to understand how two paintings were painted on a single panel | Type | A1 Journal article | ||
Year | 2019 | Publication | Journal of the American Institute for Conservation | Abbreviated Journal | |
Volume | 58 | Issue | 1-2 | Pages | 54-68 |
Keywords | A1 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
Abstract | Over the past several decades the painting An Old Man in Military Costume by Rembrandt Harmensz van Rijn (ca. 1630-31; J. Paul Getty Museum, 78.PB.246) has been the subject of a number of investigations carried out in order to better visualize a second painting beneath the surface figure. The underlying image – the head and shoulders of a man wearing a cloak – is oriented 180 degrees from the upper image and appears to be fairly complete. Scanning macro x-ray fluorescence (XRF) spectroscopy reveals the face is painted with lead white and a mercury-containing pigment (likely vermilion), and the cloak is painted with a copper-containing pigment. Following the revelation and digital color reconstruction of the underlying figure, a number of questions still remained. Here, through the use of infrared reflectance imaging spectroscopy (i.e., hyperspectral imaging) and macro-XRF imaging spectroscopy, together with cross-sections taken from targeted areas, the sequence of painting in both compositions was explored. Of particular interest was the discovery of evidence of multiple attempts to situate the lower figure, and the subsequent application of a blocking-out layer over the lower figure before the artist rotated the panel and executed the upper figure. In addition, examination of the placement of the two images on the panel adds to our understanding of the subtle complexities of Rembrandt's working process. RESUMEAu cours des dernieres decennies, la peinture Le vieil homme en costume militaire de Rembrandt Harmensz van Rijn (ca. 1630-31; J. Paul Getty Museum, 78.PB.246) a fait l'objet de nombreuses investigations menees dans le but de mieux visualiser une seconde peinture dissimulee sous la surface. L'image sous-jacente – la tete et les epaules d'un homme vetu d'une cape – est orientee a 180 degres de de l'image du vieil homme, et elle semble assez complete. La spectroscopie a macro-balayage de fluorescence X (MA-XRF) revele que le visage est peint avec du blanc de plomb et un pigment contenant du mercure (comme le vermillon), et que la cape est peinte avec un pigment a base de cuivre. Plusieurs questions restaient en suspens suite a cette decouverte et a la reconstruction numerique en couleur de l'image sous-jacente. Grace a l'emploi de techniques d'imagerie comme la spectroscopie proche infrarouge (ex., imagerie hyperspectrale) et l'imagerie MA-XRF, combinees a l'analyse de coupes stratigraphiques prelevees a des endroits cibles, on a pu explorer la sequence d'application des couches picturales de chacune des deux compositions. Une decouverte particulierement interessante est la preuve que l'artiste a fait plusieurs tentatives pour positionner la figure sous-jacente puis, a ensuite applique une couche pour la recouvrir completement avant de faire pivoter le panneau et peindre la figure du vieil homme. De plus, l'examen du positionnement des deux images sur le panneau ajoute a notre comprehension de la subtile complexite du processus de creation de Rembrandt. Traduit par Elisabeth Forest. RESUMONas ultimas decadas, a pintura Um Velho em Traje Militar, de Rembrandt Harmensz van Rijn (ca. 1630-31; J. Paul Getty Museum, 78.PB.246), foi objeto de uma serie de investigacoes realizadas para visualizar melhor uma segunda pintura abaixo da figura aparente. A imagem subjacente – a cabeca e os ombros de um homem usando uma capa – e orientada a 180 graus da imagem superior e parece estar bastante completa. O macro mapeamento de imagem por espectroscopia de fluorescencia de raios X (FRX) revela que a face e pintada com branco de chumbo e um pigmento contendo mercurio (provavelmente vermelhAo), e a capa e pintada com um pigmento contendo cobre. Apos a descoberta e reconstrucAo digital da cor da figura subjacente, uma serie de questoes ainda permanecem. EntAo, atraves da utilizacAo do mapeamento por imagem de espectroscopia de refletancia por infravermelhos (i.e. mapeamento hiperespectral) e macro mapeamento por imagem de FRX, juntamente com cortes estratigraficos de amostras retiradas de areas de interesse, a pintura em ambas as composicoes foi explorada. De particular interesse foi a descoberta de evidencias de multiplas tentativas de posicionar a figura subjacente, e a subsequente aplicacAo de uma camada intermediaria de separacAo sobre a figura inferior antes do artista girar o painel e executar a figura superior. Alem disso, o exame da colocacAo das duas imagens no painel aumenta nossa compreensAo das sutis complexidades do processo de trabalho de Rembrandt. Traduzido por Marcia Rozzi e Beatriz Haspo. RESUMENA lo largo de las ultimas decadas, la pintura Un anciano con traje militar de Rembrandt Harmensz van Rijn (ca. 1630-31; J. Paul Getty Museum, 78.PB.246) ha sido objeto de varias investigaciones realizadas con el fin de visualizar mejor una segunda pintura debajo de la figura de la superficie. La imagen subyacente, la cabeza y los hombros de un hombre que lleva una capa, esta orientada a 180 grados de la imagen superior y parece estar bastante completa. La espectroscopia de fluorescencia de rayos X (XRF) de barrido revela que la cara esta pintada con blanco de plomo y un pigmento que contiene mercurio (probablemente bermellon), y la capa esta pintada con un pigmento que contiene cobre. Tras la revelacion y la reconstruccion digital del color de la figura subyacente, aun quedaban algunas preguntas. Aqui, por medio del uso de la espectroscopia de imagenes de reflectancia infrarroja (es decir, imagenes hiperespectrales) e imagenes macro-XRF, junto con las secciones transversales tomadas de areas especificas, se exploro la secuencia de pintura en ambas composiciones. De particular interes fue el descubrimiento de evidencia de multiples intentos de situar la figura inferior, y la aplicacion posterior de una capa de bloqueo sobre la figura inferior antes de que el artista rotara el panel y ejecutara la figura superior. Ademas, el examen de la colocacion de las dos imagenes en el panel contribuye a nuestra comprension de las sutiles complejidades del proceso de trabajo de Rembrandt. Traduccion: Amparo Rueda. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000468065200005 | Publication Date | 2018-12-18 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0197-1360 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | Times cited | 2 | Open Access | ||
Notes | ; ; | Approved | Most recent IF: NA | ||
Call Number | UA @ admin @ c:irua:160407 | Serial | 5811 | ||
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Author | Wang, Y.-L.; Glatz, A.; Kimmel, G.J.; Aranson, I.S.; Thoutam, L.R.; Xiao, Z.-L.; Berdiyorov, G.R.; Peeters, F.M.; Crabtree, G.W.; Kwok, W.-K. | ||||
Title | Parallel magnetic field suppresses dissipation in superconducting nanostrips | Type | A1 Journal article | ||
Year | 2017 | Publication | America | Abbreviated Journal | P Natl Acad Sci Usa |
Volume | 114 | Issue | 48 | Pages | E10274-E10280 |
Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
Abstract | <script type='text/javascript'>document.write(unpmarked('The motion of Abrikosov vortices in type-II superconductors results in a finite resistance in the presence of an applied electric current. Elimination or reduction of the resistance via immobilization of vortices is the \u0022holy grail\u0022 of superconductivity research. Common wisdom dictates that an increase in the magnetic field escalates the loss of energy since the number of vortices increases. Here we show that this is no longer true if the magnetic field and the current are applied parallel to each other. Our experimental studies on the resistive behavior of a superconducting Mo0.79Ge0.21 nanostrip reveal the emergence of a dissipative state with increasing magnetic field, followed by a pronounced resistance drop, signifying a reentrance to the superconducting state. Large-scale simulations of the 3D time-dependent Ginzburg-Landau model indicate that the intermediate resistive state is due to an unwinding of twisted vortices. When the magnetic field increases, this instability is suppressed due to a better accommodation of the vortex lattice to the pinning configuration. Our findings show that magnetic field and geometrical confinement can suppress the dissipation induced by vortex motion and thus radically improve the performance of superconducting materials.')); | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Washington, D.C. | Editor | ||
Language | Wos | 000416891600007 | Publication Date | 2017-11-13 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0027-8424; 1091-6490 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 9.661 | Times cited | 18 | Open Access | |
Notes | ; This work was supported by the US Department of Energy (DOE), Office of Science, Office of Basic Energy Sciences, Materials Sciences and Engineering Division. The simulation was supported by the Scientific Discovery through Advanced Computing program funded by US DOE, Office of Science, Advanced Scientific Computing Research and Basic Energy Science, Division of Materials Science and Engineering. L.R.T. and Z.-L.X. acknowledge support through National Science Foundation Grant DMR-1407175. Use of the Center for Nanoscale Materials, an Office of Science user facility, was supported by the DOE, Office of Science, Office of Basic Energy Sciences, under Contract DE-AC02-06CH11357. ; | Approved | Most recent IF: 9.661 | ||
Call Number | UA @ lucian @ c:irua:147697 | Serial | 4889 | ||
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Author | Tian, H.; Schryvers, D.; Claeys, P. | ||||
Title | Nanodiamonds do not provide unique evidence for a Younger Dryas impact | Type | A1 Journal article | ||
Year | 2011 | Publication | Proceedings of the National Academy of Sciences of the United States of America | Abbreviated Journal | P Natl Acad Sci Usa |
Volume | 108 | Issue | 1 | Pages | 40-44 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Microstructural, δ13C isotope and C/N ratio investigations were conducted on excavated material from the black Younger Dryas boundary in Lommel, Belgium, aiming for a characterisation of the carbon content and structures. Cubic diamond nanoparticles are found in large numbers. The larger ones with diameters around or above 10 nm often exhibit single or multiple twins. The smaller ones around 5 nm in diameter are mostly defect-free. Also larger flake-like particles, around 100 nm in lateral dimension, with a cubic diamond structure are observed as well as large carbon onion structures. The combination of these characteristics does not yield unique evidence for an exogenic impact related to the investigated layer. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Washington, D.C. | Editor | ||
Language | Wos | 000285915000012 | Publication Date | 2010-12-21 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0027-8424;1091-6490; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 9.661 | Times cited | 32 | Open Access | |
Notes | Approved | Most recent IF: 9.661; 2011 IF: 9.681 | |||
Call Number | UA @ lucian @ c:irua:88733 | Serial | 2254 | ||
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