Records |
Author |
Annegarn, H.J.; Storms, H.; Van Grieken, R.E.; Booth-Jones, P.A. |
Title |
Composition and size of individual particles from a gold mine atmosphere |
Type |
A3 Journal article |
Year |
1987 |
Publication |
Mining science & technology |
Abbreviated Journal |
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Volume |
5 |
Issue |
2 |
Pages |
111-119 |
Keywords |
A3 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Airborne dust particles were collected in a return airway of a South African gold mine using a 7-stage, single-orifice cascade impactor. Between 70 and 130 individual particles were analysed on each stage using automated electron-probe x-ray microanalysis (EPXMA). Particle size and shape parameters are given for different classes of particles sorted by elemental composition. Silicon-rich particles are the most abundant overall, while chlorine-rich particles dominate (up to 80%) in the range 0.21.0 μm. It is shown that EPXMA characterisation of particles can be used to infer relative contributions of various particle sources and dust generating processes to the total dust concentrations in mine atmospheres. An understanding of the nature and source of particles is essential for any source control strategy. We conclude that the EPXMA technique merits inclusion in the repertoire of techniques used for characterising underground dust. |
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Wos |
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Publication Date |
2004-12-15 |
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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 |
0167-9031 |
ISBN |
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Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:116777 |
Serial |
7701 |
Permanent link to this record |
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Author |
Annegarn, H.J.; Van Grieken, R.E.; Dibby, D.M.; Von Blottnitz, F. |
Title |
Background aerosol composition in the Namib Desert, South West-Africa (Namibia) |
Type |
A1 Journal article |
Year |
1983 |
Publication |
Atmospheric environment : an international journal |
Abbreviated Journal |
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Volume |
17 |
Issue |
10 |
Pages |
2045-2053 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
A remote site in the Namib Desert was selected for sampling background aerosols in southern Africa, as one of a wide network of stations spanning the Southern Hemisphere in a programme designed to measure the background concentrations of trace elements in the atmosphere. A series of samples was collected over a 6-month period using a single-orifice cascade impactor, which fractionated the particles into six size groups. Analysis was performed using particle-induced X-ray emission (PIXE), yielding results for S, Cl, K, Ca, Ti, Mn, Fe, Br and Sr, and occasionally also for V, Cr, Ni, Cu, Zn and Pb. No direct correlations with wind direction were observed excluding strong local or regional sources of particles. K, Ca, Ti, Mn and Fe can be identified with a dust dispersion source. Cl, large particle S and Br, and part of the K and Sr are derived from sea spray. Relative to the soil components small particle K is not enriched as it normally is in regions with less scarce vegetation. Cr, V, Ni, Cu, Zn and Pb concentrations and enrichments in the aerosol are lower than practically all values measured at any other location hitherto. The concentration of the small particle sulphur, 200 ng m−3, is believed to be related to anaerobic conditions and plankton blooms in the ocean upwelling zones off Namibia. |
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Wos |
A1983RP58300017 |
Publication Date |
2003-08-06 |
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 |
1352-2310 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:113623 |
Serial |
7545 |
Permanent link to this record |
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Author |
Annegarn, H.J.; Van Grieken, R.E.; Winchester, J.W.; Sellschop, J.P.F.; von Blottnitz, F. |
Title |
Background aerosol concentrations at the Namib-Atlantic interface |
Type |
P3 Proceeding |
Year |
1979 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
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Keywords |
P3 Proceeding; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
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Edition |
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ISBN |
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Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:117465 |
Serial |
7546 |
Permanent link to this record |
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Author |
Annys, A.; Jannis, D.; Verbeeck, J. |
Title |
Core-loss EELS dataset and neural networks for element identification |
Type |
Dataset |
Year |
2023 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
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Keywords |
Dataset; Electron microscopy for materials research (EMAT) |
Abstract |
We present a large dataset containing simulated core-loss electron energy loss spectroscopy (EELS) spectra with the elemental content as ground-truth labels. Additionally we present some neural networks trained on this data for element identification. The simulated dataset contains zero padded core-loss spectra from 0 to 3072 eV, which represents 107 core-loss edges through all 80 elements from Be up to Bi. The core-loss edges are calculated from the generalised oscillator strength (GOS) database presented by Zhang et al.[1] Generic fine structures using lifetime broadened peaks are used to imitate fine structure due to solid-state effects in experimental spectra. Generic low-loss regions are used to imitate the effect of multiple scattering. Each spectrum contains at least one edge of a given query element and possibly additional edges depending on samples drawn from The Materials Project [2]. The dataset contains for each of the 80 elements: 7000 training spectra, 1500 test spectra, 600 validation spectra and 100 spectra representing only the query element. This results in a total 736 000 labeled spectra. Code on how to – read the simulated data – transform HDF5 format to TFRecord format – train and evaluate neural networks using the simulated data – use the trained networks for automated element identification is available on GitHub at arnoannys/EELS_ID A full report on the simulation of the dataset and the training and evaluation of the neural networks can be found at: Annys, A., Jannis, D. & Verbeeck, J. Deep learning for automated materials characterisation in core-loss electron energy loss spectroscopy. Sci Rep 13, 13724 (2023). https://doi.org/10.1038/s41598-023-40943-7 [1] Zezhong Zhang, Ivan Lobato, Daen Jannis, Johan Verbeeck, Sandra Van Aert, & Peter Nellist. (2023). Generalised oscillator strength for core-shell electron excitation by fast electrons based on Dirac solutions (1.0) [Data set]. Zenodo. https://doi.org/10.5281/zenodo.7729585 [2] Anubhav Jain, Shyue Ping Ong, Geoffroy Hautier, Wei Chen, William Davidson Richards, Stephen Dacek, Shreyas Cholia, Dan Gunter, David Skinner, Gerbrand Ceder, Kristin A. Persson; Commentary: The Materials Project: A materials genome approach to accelerating materials innovation. APL Mater 1 July 2013; 1 (1): 011002. [https://doi.org/10.1063/1.4812323](https://doi.org/10.1063/1.4812323) |
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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 |
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 |
Call Number |
UA @ admin @ c:irua:203391 |
Serial |
9015 |
Permanent link to this record |
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Author |
Annys, A.; Jannis, D.; Verbeeck, J.; Annys, A.; Jannis, D.; Verbeeck, J. |
Title |
Deep learning for automated materials characterisation in core-loss electron energy loss spectroscopy |
Type |
A1 Journal article |
Year |
2023 |
Publication |
Scientific reports |
Abbreviated Journal |
|
Volume |
13 |
Issue |
1 |
Pages |
13724 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Electron energy loss spectroscopy (EELS) is a well established technique in electron microscopy that yields information on the elemental content of a sample in a very direct manner. One of the persisting limitations of EELS is the requirement for manual identification of core-loss edges and their corresponding elements. This can be especially bothersome in spectrum imaging, where a large amount of spectra are recorded when spatially scanning over a sample area. This paper introduces a synthetic dataset with 736,000 labeled EELS spectra, computed from available generalized oscillator strength tables, that represents 107 K, L, M or N core-loss edges and 80 chemical elements. Generic lifetime broadened peaks are used to mimic the fine structure due to band structure effects present in experimental core-loss edges. The proposed dataset is used to train and evaluate a series of neural network architectures, being a multilayer perceptron, a convolutional neural network, a U-Net, a residual neural network, a vision transformer and a compact convolutional transformer. An ensemble of neural networks is used to further increase performance. The ensemble network is used to demonstrate fully automated elemental mapping in a spectrum image, both by directly mapping the predicted elemental content and by using the predicted content as input for a physical model-based mapping. |
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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 |
001052937600046 |
Publication Date |
2023-08-22 |
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 |
2045-2322 |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
4.6 |
Times cited |
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Open Access |
OpenAccess |
Notes |
A.A. would like to acknowledge the resources and services used in this work provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation – Flanders (FWO) and the Flemish Government. J.V. acknowledges the IMPRESS project. The IMPRESS project has received funding from the HORIZON EUROPE framework program for research and innovation under grant agreement n. 101094299. |
Approved |
Most recent IF: 4.6; 2023 IF: 4.259 |
Call Number |
UA @ admin @ c:irua:198647 |
Serial |
8846 |
Permanent link to this record |
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Author |
Annys, S.; Adgo, E.; Ghebreyohannes, T.; Van Passel, S.; Dessein, J.; Nyssen, J. |
Title |
Impacts of the hydropower-controlled Tana-Beles interbasin water transfer on downstream rural livelihoods (northwest Ethiopia) |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Journal Of Hydrology |
Abbreviated Journal |
J Hydrol |
Volume |
569 |
Issue |
569 |
Pages |
436-448 |
Keywords |
A1 Journal article; Economics; Engineering sciences. Technology; Engineering Management (ENM) |
Abstract |
Despite public awareness of unintended impacts (1980s) and well-developed international standards (2000s), downstream impacts of large hydropower projects still very often are not properly assessed. Impacts of (hydropower-regulated) interbasin water transfers (IBWTs) are considered self-evidently positive, although they can have far-reaching consequences for hydrogeomorphological systems and consequently river-dependent communities. In this study, the downstream direct and indirect impacts of the Ethiopian hydropower-regulated Tana-Beles IBWT are evaluated in an interdisciplinary way. The components of the framework of rural livelihoods are considered and changing contexts, resources availabilities and livelihood strategies are analysed. Mixed methods are applied, combining hydrogeomorphological field observations, GIS analyses, scientific literature, policy documents, and semi-structured interviews with local people and local to federal authorities. Results show that the IBWT drastically increased the Beles rivers discharge (with an average release of +92 m3 s−1 at the outlet; *2 in rainy season and *12 in dry season 100 km downstream of the water release) and introduced dangerous situations for local communities (over 250 people drowned in the river). River bank erosion resulted in the uncompensated loss of farmland (163 ha) and the establishment of large-scale commercial farms increased the pressure on land and led to the impoverishment of displaced communities (4310 households). The project was implemented top-down, without any transparency, benefit sharing or compensation for external costs. This stresses the importance of downstream interdisciplinary impact assessments and highlights the need for decent in-depth ex post-analyses of hydropower projects. Environmental impact assessments should be taken seriously and cannot be considered a formality. In Ethiopia and in many developing countries, the hydropower industry is booming. Although dams and IBWTs can be the best solution for water-related problems in specific contexts, national development goals (such as the expansion of the electricity network) should not be at the expense of rural livelihoods. |
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Language |
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Wos |
000457952900032 |
Publication Date |
2018-12-15 |
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 |
0022-1694 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.483 |
Times cited |
2 |
Open Access |
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Notes |
; This study was funded by the Flemish Research Foundation (FWO, Belgium), through project No. G022217N and a specific travel grant for a long stay abroad (No. V445417N). We acknowledge the cooperation with the Bahir Dar University VLIR-UOS IUC programme. All support given by Bahir Dar University has been greatly appreciated and many thanks go to Yonnas Shawul and Deribew Fenetie, for assisting and translating in the field. Staff of various ranks in administrative offices are thanked for their cooperation and mostly openness during interviews. Special thanks go to the local farmers and other rural dwellers, for their cooperation and contribution to this research. We thank the two anonymous reviewers for their constructive comments. ; |
Approved |
Most recent IF: 3.483 |
Call Number |
UA @ admin @ c:irua:156935 |
Serial |
6215 |
Permanent link to this record |
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Author |
Annys, S.; Van Passel, S.; Dessein, J.; Adgo, E.; Nyssen, J. |
Title |
From fast-track implementation to livelihood deterioration: The dam-based Ribb Irrigation and Drainage Project in Northwest Ethiopia |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Agricultural Systems |
Abbreviated Journal |
Agr Syst |
Volume |
184 |
Issue |
|
Pages |
102909-102913 |
Keywords |
A1 Journal article; Engineering Management (ENM) |
Abstract |
The 21st century revival of large-scale water resources development projects makes it important to keep assessing their impacts – preferably from an interdisciplinary perspective – in order to not repeat past mistakes and explore whether they could improve livelihood conditions for rural communities. In this study, costs and benefits of the World Bank-funded Ribb Irrigation and Drainage Project (RIDP) were investigated using a unique systems approach. The impact for farmers with different initial farming systems (rainfed – residual moisture – irrigated) was studied using field observations, document analyses, remote sensing, agronomic data and semi-structured interviews (n = 165). Data on project-induced changes to land and water availability, cropping patterns, farming systems and farm-level economics were collected. The results show that dam and dyke construction has reduced flooding, which has resulted in declining rice productivity ( – 42%) and concomitant shifts to lower value cropping systems. Results also reveal that the land redistribution has caused widespread livelihood deterioration as households had to give up 25% of their farmland and the communal grazing land was fully converted into farmland. Due to top-down implementation, nontransparent communication, delayed construction and lagging financial compensation, social resistance has appeared in the command area, impeding the construction works. In addition to these problems, if no rapid change to higher value crops can be realized, 20.5% of the farmers (those who already irrigate) will experience a loss of livelihood, 64.1% of the farmers (those with rainfed and residual moisture cultivation) will be on the verge of livelihood deterioration and only 13.5% of the farmers (those with solely rainfed cultivation) will enjoy RIDP-induced improved livelihoods. The fate of this project stresses the importance of investigating initial farming systems, exploring worthy project alternatives, improving participation, communication and benefit-sharing and strengthening the institutional capacity of implementing authorities. |
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Thesis |
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Place of Publication |
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Language |
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Wos |
000564756600013 |
Publication Date |
2020-08-08 |
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 |
0308-521x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.6 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 6.6; 2020 IF: 2.571 |
Call Number |
UA @ admin @ c:irua:172030 |
Serial |
6927 |
Permanent link to this record |
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Author |
Annys, S.; Van Passel, S.; Dessein, J.; Ghebreyohannes, T.; Adgo, E.; Nyssen, J. |
Title |
Small-scale irrigation expansion along the dam-regulated Tekeze River in Northern Ethiopia |
Type |
A1 Journal article |
Year |
2020 |
Publication |
International Journal Of Water Resources Development |
Abbreviated Journal |
Int J Water Resour D |
Volume |
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Issue |
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Pages |
1-22 |
Keywords |
A1 Journal article; Engineering Management (ENM) |
Abstract |
Based on extensive field information, farmer-led small-scale irrigation systems along the dam-regulated Tekeze River is investigated and the likelihood of future irrigation expansion within the area with modelled potential is discussed, considering facilitating and hampering factors. Due to dam-induced hydrologic alterations, downstream socio-ecological systems have strongly transformed as the irrigated area has quadrupled and the post-dam potential for perennial crop cultivation has attracted numerous migrant investors to the area, inducing inequalities but also providing opportunities. Future dam construction should involve tailored policy interventions to facilitate irrigation expansion, while safeguarding equal and sustainable access to water and land. |
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Place of Publication |
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Wos |
000569995600001 |
Publication Date |
2020-09-16 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0790-0627 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.1 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 3.1; 2020 IF: 2.088 |
Call Number |
UA @ admin @ c:irua:171952 |
Serial |
6943 |
Permanent link to this record |
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Author |
Antipov, E.V.; Abakumov, A.M.; Alekseeva, A.M.; Rozova, M.G.; Hadermann, J.; Lebedev, O.I.; Van Tendeloo, G. |
Title |
Oxygen and fluorine doping in Sr2MnGaO5 brownmillerite |
Type |
A1 Journal article |
Year |
2004 |
Publication |
Physica status solidi: A: applied research |
Abbreviated Journal |
Phys Status Solidi A |
Volume |
201 |
Issue |
7 |
Pages |
1403-1409 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Berlin |
Editor |
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Language |
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Wos |
000221836300008 |
Publication Date |
2004-04-21 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0031-8965;1521-396X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
9 |
Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:49464 |
Serial |
2544 |
Permanent link to this record |
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Author |
Antipov, E.V.; Khasanova, N.R.; Pshirkov, J.S.; Putilin, S.N.; Bougerof, C.; Lebedev, O.I.; Van Tendeloo, G.; Baranov, A.; Park, Y.W. |
Title |
The superconducting bismuth-based mixed oxides |
Type |
A1 Journal article |
Year |
2003 |
Publication |
Journal of low temperature physics
T2 – International Conference on Physics and Chemistry of Molecular and Oxide, Superconductors (MOS2002), AUG 13-18, 2002, HSINCHU, TAIWAN |
Abbreviated Journal |
J Low Temp Phys |
Volume |
131 |
Issue |
3-4 |
Pages |
575-587 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The present paper describes the synthesis, characterization of mixed-valence bismuthates with 3- or 2-dimensional perovskite-like structures and structural criteria that influence superconductivity in these compounds. Single-phase samples of Sr1-xKxBiO3 were prepared for the broad range of K-content: 0.25 less than or equal to x less than or equal to 0.65. For these bismuthates the symmetry of the structure changes from monoclinic to orthorhombic and finally to tetragonal upon increasing the K-content thus resulting in the decrease of the Bi-O distances and reduction of the network distortions. Superconductivity with maximum T-c = 12K exists in the narrow range (x approximate to 0.5 – 0.6) within the stability field of the tetragonal phase (0.33 less than or equal to x less than or equal to 0.65), when the 3-dimensional octahedral framework has close to the ideal perovskite structure arrangement. At the same time compositions with close to optimal Bi-valence (x = 0.33 and 0.43) do not show any sign of superconductivity, probably, due to structural distortions. The layered type (BaK)(3)Bi2O7 and (Ba,K)(2)BiO4 bismuthates belonging to the A(n+1)B(n)O(3n+1) homologous series were investigated Buckling of the (BiO2) layers in the structure of the n = 2 member was revealed The formation of the n=1 bismuthate was found by Electron Microscopy and X-ray powder diffraction studies. Both types of compounds are considered to be possible candidates for new superconducting materials among bismuthates. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York |
Editor |
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Language |
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Wos |
000181768000061 |
Publication Date |
2003-04-07 |
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 |
0022-2291; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.3 |
Times cited |
3 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.3; 2003 IF: 1.171 |
Call Number |
UA @ lucian @ c:irua:102803 |
Serial |
3597 |
Permanent link to this record |
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Author |
Antipov, E.V.; Khasanova, N.R.; Pshirkov, J.S.; Putilin, S.N.; Bougerol, C.; Lebedev, O.I.; Van Tendeloo, G.; Baranov, A.N.; Park, Y.W. |
Title |
The superconducting bismuth-based mixed oxides |
Type |
A1 Journal article |
Year |
2002 |
Publication |
Current applied physics
T2 – QTSM and QFS 02 Symposium, MAY 08-10, 2002, SEOUL, SOUTH KOREA |
Abbreviated Journal |
Curr Appl Phys |
Volume |
2 |
Issue |
5 |
Pages |
425-430 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The present paper describes the synthesis, characterization of mixed-valence bismuthates with three- or two-dimensional perovskite-like structures and structural criteria that influence superconductivity in these compounds. Single-phase samples of Sr1-xKxBiO3 were prepared for the broad range of K-content: 0.25 less than or equal to x less than or equal to 0.65. For these bismuthates the symmetry of the structure changes from monoclinic to orthorhombic and finally to tetragonal upon increasing the K-content thus resulting in the decrease of the Bi-O distances and reduction of the network distortions. Superconductivity with maximum T-c = 12 K exists in the narrow range (x approximate to 0.5-0.6) within the stability field of the tetragonal phase (0.33 less than or equal to x less than or equal to 0.65), when the three-dimensional octahedral framework has close to the ideal perovskite structure arrangement. The layered type (Ba,K)(3)Bi2O7 and (Ba,K)(2)BiO4 bismuthates belonging to the A(n+1)B(n)O(3n+1) homologous series were investigated. Buckling of the (BiO2) layers in the structure of the n = 2 member occurs due to the ordering of alkaline- and alkaline-earth cations between two independent positions. The formation of the one-layer bismuthate was revealed by Electron Microscopy and XRPD studies. Both types of compounds are considered to be possible candidates for new superconducting materials among bismuthates. (C) 2002 Published by Elsevier Science B.V. |
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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 |
000179330900015 |
Publication Date |
2002-11-04 |
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 |
1567-1739; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.971 |
Times cited |
2 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.971; 2002 IF: NA |
Call Number |
UA @ lucian @ c:irua:103336 |
Serial |
3598 |
Permanent link to this record |
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|
Author |
Antipov, E.V.; Putilin, S.N.; Shpanchenko, R.V.; Alyoshin, V.A.; Rozova, M.G.; Abakumov, A.M.; Mikhailova, D.A.; Balagurov, A.M.; Lebedev, O.; Van Tendeloo, G. |
Title |
Structural features, oxygen and fluorine doping in Cu-based superconductors |
Type |
A1 Journal article |
Year |
1997 |
Publication |
Physica: C : superconductivity
T2 – International Conference on Materials and Mechanisms of, Superconductivity – High Temperature Superconductors V, Feb. 28-Mar. 04, 1997, Beijing, Peoples R. China |
Abbreviated Journal |
Physica C |
Volume |
282 |
Issue |
Part 1 |
Pages |
61-64 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The variation of structures and superconducting properties by changing extra oxygen or fluorine atoms concentration in Hg-based Cu mixed oxides and YBa2Cu3O6+delta was studied. The data obtained by NPD study of Hg-1201 can be considered as an evidence of the conventional oxygen doping mechanism with 2 delta holes per (CuO2) layer. The extra oxygen atom was found to be located in the middle of the Hg mesh only. Different formal charges of oxygen and fluorine inserted into reduced 123 structure results in its distinct variations. The fluorine incorporation into strongly reduced YBa2Cu3O6+delta causes a significant structural rearrangement and the formation of a new compound with a composition close to YBa2Cu3O6F2 (tetragonal alpha = 3.87 Angstrom and c approximate to 13 Angstrom), which structure was deduced from the combined results of X-ray diffraction, electron diffraction and high resolution electron microscopy. Fluorination treatment by XeF2 of nonsuperconducting 123 samples causes an appearance of bulk superconductivity with T-c up to 94K. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
Elsevier Science |
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
A1997XZ90400019 |
Publication Date |
2002-07-25 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0921-4534; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.404 |
Times cited |
10 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.404; 1997 IF: 2.199 |
Call Number |
UA @ lucian @ c:irua:95866 |
Serial |
3237 |
Permanent link to this record |
|
|
|
Author |
Anđelković, M. |
Title |
O(N) numerical methods for investigating graphene heterostructures and moiré patterns |
Type |
Doctoral thesis |
Year |
2019 |
Publication |
|
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
207 p. |
Keywords |
Doctoral thesis; Condensed Matter Theory (CMT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
|
Publication Date |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
|
ISBN |
|
Additional Links |
UA library record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:165205 |
Serial |
6315 |
Permanent link to this record |
|
|
|
Author |
Ao, Z.; Jiang, Q.; Li, S.; Liu, H.; Peeters, F.M.; Li, S.; Wang, G. |
Title |
Enhancement of the stability of fluorine atoms on defective graphene and at graphene/fluorographene interface |
Type |
A1 Journal article |
Year |
2015 |
Publication |
ACS applied materials and interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
Volume |
7 |
Issue |
7 |
Pages |
19659-19665 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Fluorinated graphene is one of the most important derivatives of graphene and has been found to have great potential in optoelectronic and photonic nanodevices. However, the stability of F atoms on fluorinated graphene under different conditions, which is essential to maintain the desired properties of fluorinated graphene, is still unclear. In this work, we investigate the diffusion of F atoms on pristine graphene, graphene with defects, and at graphene/fluorographene interfaces by using density functional theory calculations. We find that an isolated F atom diffuses easily on graphene, but those F atoms can be localized by inducing vacancies or absorbates in graphene and by creating graphene/fluorographene interfaces, which would strengthen the binding energy of F atoms on graphene and increase the diffusion energy barrier of F atoms remarkably. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000361252400018 |
Publication Date |
2015-08-24 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1944-8244 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
7.504 |
Times cited |
35 |
Open Access |
|
Notes |
; We acknowledge the financial supports from the Chancellor's Research Fellowship Program of the University of Technology Sydney, the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish Government. This research was also supported by the National Computational Infrastructure (NCI) through the merit allocation scheme and used the NCI resources and facilities in Canberra, Australia. ; |
Approved |
Most recent IF: 7.504; 2015 IF: 6.723 |
Call Number |
UA @ lucian @ c:irua:128703 |
Serial |
4177 |
Permanent link to this record |
|
|
|
Author |
Ao, Z.M.; Hernández-Nieves, A.D.; Peeters, F.M.; Li, S. |
Title |
Enhanced stability of hydrogen atoms at the graphene/graphane interface of nanoribbons |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
97 |
Issue |
23 |
Pages |
233109,1-233109,3 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The thermal stability of graphene/graphane nanoribbons (GGNRs) is investigated using density functional theory. It is found that the energy barriers for the diffusion of hydrogen atoms on the zigzag and armchair interfaces of GGNRs are 2.86 and 3.17 eV, respectively, while the diffusion barrier of an isolated H atom on pristine graphene was only ∼ 0.3 eV. These results unambiguously demonstrate that the thermal stability of GGNRs can be enhanced significantly by increasing the hydrogen diffusion barriers through graphene/graphane interface engineering. This may provide new insights for viable applications of GGNRs. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000285364000067 |
Publication Date |
2010-12-11 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0003-6951; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.411 |
Times cited |
43 |
Open Access |
|
Notes |
; The financial supports by the Vice-Chancellor's Postdoctoral Research Fellowship Program of the University of New South Wales (SIR50/PS19184), the Flemish Science Foundation (FWO-VI), and the Belgian Science Policy (IAP) are acknowledged. A.D.H. acknowledges also support from ANPCyT (Grant No. PICT2008-2236) and the collaborative project FWO-MINCyT (FW/08/01). ; |
Approved |
Most recent IF: 3.411; 2010 IF: 3.841 |
Call Number |
UA @ lucian @ c:irua:86972 |
Serial |
1056 |
Permanent link to this record |
|
|
|
Author |
Ao, Z.M.; Hernández-Nieves, A.D.; Peeters, F.M.; Li, S. |
Title |
The electric field as a novel switch for uptake/release of hydrogen for storage in nitrogen doped graphene |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
Volume |
14 |
Issue |
4 |
Pages |
1463-1467 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Nitrogen-doped graphene was recently synthesized and was reported to be a catalyst for hydrogen dissociative adsorption under a perpendicular applied electric field (F). In this work, the diffusion of H atoms on N-doped graphene, in the presence and absence of an applied perpendicular electric field, is studied using density functional theory. We demonstrate that the applied field can significantly facilitate the binding of hydrogen molecules on N-doped graphene through dissociative adsorption and diffusion on the surface. By removing the applied field the absorbed H atoms can be released efficiently. Our theoretical calculation indicates that N-doped graphene is a promising hydrogen storage material with reversible hydrogen adsorption/desorption where the applied electric field can act as a switch for the uptake/release processes. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
000298754500018 |
Publication Date |
2011-11-21 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1463-9076;1463-9084; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.123 |
Times cited |
67 |
Open Access |
|
Notes |
; Financial support of the Vice-Chancellor's Postdoctoral Research Fellowship Program (SIR50/PS19184) and the ECR grant (SIR30/PS24201) from the University of New South Wales are acknowledged. This work is also supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). ; |
Approved |
Most recent IF: 4.123; 2012 IF: 3.829 |
Call Number |
UA @ lucian @ c:irua:96266 |
Serial |
3578 |
Permanent link to this record |
|
|
|
Author |
Ao, Z.M.; Peeters, F.M. |
Title |
Electric field: A catalyst for hydrogenation of graphene |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
96 |
Issue |
25 |
Pages |
3 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Due to the importance of hydrogenation of graphene for several applications, we present an alternative approach to hydrogenate graphene based on density functional theory calculations. We find that a negative perpendicular electric field F can act as a catalyst to reduce the energy barrier for molecular H<sub>2</sub> dissociative adsorption on graphene. Increasing -F above 0.02 a.u. (1 a.u.=5.14×10<sup>11</sup> V/m), this hydrogenation process occurs smoothly without any potential barrier. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000279168100052 |
Publication Date |
2010-06-23 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0003-6951; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.411 |
Times cited |
88 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). ; |
Approved |
Most recent IF: 3.411; 2010 IF: 3.841 |
Call Number |
UA @ lucian @ c:irua:83924 |
Serial |
881 |
Permanent link to this record |
|
|
|
Author |
Ao, Z.M.; Peeters, F.M. |
Title |
Electric field activated hydrogen dissociative adsorption to nitrogen-doped graphene |
Type |
A1 Journal article |
Year |
2010 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
Volume |
114 |
Issue |
34 |
Pages |
14503-14509 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Graphane, hydrogenated graphene, was very recently synthesized and predicted to have great potential applications. In this work, we propose a new promising approach for hydrogenation of graphene based on density functional theory (DFT) calculations through the application of a perpendicular electric field after substitutionally doping by nitrogen atoms. These DFT calculations show that the doping by nitrogen atoms into the graphene layer and applying an electrical field normal to the graphene surface induce dissociative adsorption of hydrogen. The dissociative adsorption energy barrier of an H2 molecule on a pristine graphene layer changes from 2.7 to 2.5 eV on N-doped graphene, and to 0.88 eV on N-doped graphene under an electric field of 0.005 au. When increasing the electric field above 0.01 au, the reaction barrier disappears. Therefore, N doping and applying an electric field have catalytic effects on the hydrogenation of graphene, which can be used for hydrogen storage purposes and nanoelectronic applications. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
Language |
|
Wos |
000281129100027 |
Publication Date |
2010-08-09 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1932-7447;1932-7455; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.536 |
Times cited |
110 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-VI) and the Belgian Science Policy (IAP). ; |
Approved |
Most recent IF: 4.536; 2010 IF: 4.524 |
Call Number |
UA @ lucian @ c:irua:84588 |
Serial |
882 |
Permanent link to this record |
|
|
|
Author |
Ao, Z.M.; Peeters, F.M. |
Title |
High-capacity hydrogen storage in Al-adsorbed graphene |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
81 |
Issue |
20 |
Pages |
205406,1-205406,7 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
A high-capacity hydrogen storage mediumAl-adsorbed grapheneis proposed based on density-functional theory calculations. We find that a graphene layer with Al adsorbed on both sides can store hydrogen up to 13.79 wt % with average adsorption energy −0.193 eV/H2. Its hydrogen storage capacity is in excess of 6 wt %, surpassing U. S. Department of Energy (DOEs) target. Based on the binding-energy criterion and molecular-dynamics calculations, we find that hydrogen storage can be recycled at near ambient conditions. This high-capacity hydrogen storage is due to the adsorbed Al atoms that act as bridges to link the electron clouds of the H2 molecules and the graphene layer. As a consequence, a two-layer arrangement of H2 molecules is formed on each side of the Al-adsorbed graphene layer. The H2 concentration in the hydrogen storage medium can be measured by the change in the conductivity of the graphene layer. |
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000278144500082 |
Publication Date |
2010-05-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
219 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO) and the Belgian Science Policy (IAP). ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
Call Number |
UA @ lucian @ c:irua:83386 |
Serial |
1422 |
Permanent link to this record |
|
|
|
Author |
Apolinario, S.W.S.; Aguiar, J.A.; Peeters, F.M. |
Title |
Angular melting scenarios in binary dusty-plasma Coulomb balls : magic versus normal clusters |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Physical review : E : statistical, nonlinear, and soft matter physics |
Abbreviated Journal |
Phys Rev E |
Volume |
90 |
Issue |
6 |
Pages |
063113 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Molecular-dynamic simulations were performed in order to investigate the melting processes of isotropically confined binary systems. We considered two species of particles, which differ by their amount of electric charge. A Lindemann type of criterion was used to determine the angular melting temperature. We demonstrate that the magic-to-normal cluster transition can evolve in two distinct ways, that is, through a structural phase transition of the first order or via a smooth transition where an increase of the shells' width leads to a continuous decreasing mechanical stability of the system. Moreover, for large systems, we demonstrate that the internal cluster exerts a minor effect on the mechanical stability of the external shell. Furthermore, we show that highly symmetric configurations, such as those found for multiple ring structures, have large mechanical stability, i.e., high angular melting temperature. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
Woodbury (NY) |
Editor |
|
Language |
|
Wos |
000347207000027 |
Publication Date |
2014-12-29 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1539-3755;1550-2376; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.366 |
Times cited |
1 |
Open Access |
|
Notes |
; This work was supported by FACEPE (Fundacao de Amparo a Ciencia e Tecnologia do Estado de Pernambuco) Grant No. APQ-1800-1.05/ 12, the bilatera project between CNPq and FWO-VL, and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 2.366; 2014 IF: 2.288 |
Call Number |
UA @ lucian @ c:irua:122828 |
Serial |
116 |
Permanent link to this record |
|
|
|
Author |
Apolinario, S.W.S.; Partoens, B.; Peeters, F.M. |
Title |
Inhomogeneous melting in anisotropically confined two-dimensional clusters |
Type |
A1 Journal article |
Year |
2006 |
Publication |
Physical review : E : statistical physics, plasmas, fluids, and related interdisciplinary topics |
Abbreviated Journal |
Phys Rev E |
Volume |
74 |
Issue |
3 |
Pages |
031107,1-11 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000240870100019 |
Publication Date |
2006-09-12 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1539-3755;1550-2376; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.366 |
Times cited |
25 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.366; 2006 IF: 2.438 |
Call Number |
UA @ lucian @ c:irua:60998 |
Serial |
1668 |
Permanent link to this record |
|
|
|
Author |
Apolinario, S.W.S.; Partoens, B.; Peeters, F.M. |
Title |
Multiple rings in a 3D anisotropic Wigner crystal: structural and dynamical properties |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
77 |
Issue |
3 |
Pages |
035321,1-9 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000252862900102 |
Publication Date |
2008-01-16 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
17 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2008 IF: 3.322 |
Call Number |
UA @ lucian @ c:irua:67821 |
Serial |
2229 |
Permanent link to this record |
|
|
|
Author |
Apolinario, S.W.S.; Partoens, B.; Peeters, F.M. |
Title |
Structural and dynamical aspects of small three-dimensional spherical Coulomb clusters |
Type |
A1 Journal article |
Year |
2007 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
Volume |
9 |
Issue |
|
Pages |
283,1-29 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000249112500001 |
Publication Date |
2007-08-25 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1367-2630; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.786 |
Times cited |
44 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.786; 2007 IF: 3.264 |
Call Number |
UA @ lucian @ c:irua:66120 |
Serial |
3193 |
Permanent link to this record |
|
|
|
Author |
Apolinario, S.W.S.; Partoens, B.; Peeters, F.M. |
Title |
Structure and spectrum of anisotropically confined two-dimensional clusters with logarithmic interaction |
Type |
A1 Journal article |
Year |
2005 |
Publication |
Physical review : E : statistical physics, plasmas, fluids, and related interdisciplinary topics |
Abbreviated Journal |
Phys Rev E |
Volume |
72 |
Issue |
|
Pages |
046122,1-7 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We studied the structural and spectral properties of a classical system consisting of a finite number of particles, moving in two dimensions, and interacting through a repulsive logarithmic potential and held together by an anisotropic harmonic potential. Increasing the anisotropy of the confinement potential can drive the system from a two-dimensional (2D) to a one-dimensional (1D) configuration. This change occurs through a sequence of structural transitions of first and second order which are reflected in the normal mode frequencies. Our results of the ground state configurations are compared with recent experiments and we obtained a satisfactory agreement. The transition from the 1D line structure to the 2D structure occurs through a zigzag transition which is of second order. We found analytical expressions for the eigenfrequencies before the zigzag transition, which allowed us to obtain an analytical expression for the anisotropy parameter at which the zigzag transition occurs as a function of the number of particles in the system. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000232931200034 |
Publication Date |
2005-10-18 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1539-3755;1550-2376; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.366 |
Times cited |
22 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.366; 2005 IF: 2.418 |
Call Number |
UA @ lucian @ c:irua:62448 |
Serial |
3295 |
Permanent link to this record |
|
|
|
Author |
Apolinario, S.W.S.; Peeters, F.M. |
Title |
Binary dusty plasma Coulomb balls |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review : E : statistical physics, plasmas, fluids, and related interdisciplinary topics |
Abbreviated Journal |
Phys Rev E |
Volume |
83 |
Issue |
4 |
Pages |
041136,1-041136,8 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We investigated the mixing and segregation of a system consisting of two different species of particles, having different charges, interacting through a pure Coulomb potential, and confined in a three-dimensional parabolic trap. The structure of the cluster and its normal mode spectrum are analyzed as a function of the relative charge and the relative number of different types of particles. We found that (a) the system can be in a mixed or segregated state depending on the relative charge ratio parameter and (b) the segregation process is mediated by a first or second order structural phase transition which strongly influences the magic cluster properties of the system. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000290154900004 |
Publication Date |
2011-04-29 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1539-3755;1550-2376; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.366 |
Times cited |
10 |
Open Access |
|
Notes |
; This work was supported by FACEPE (Fundacao de Amparo a Ciencia e Tecnologia do Estado de Pernambuco) and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 2.366; 2011 IF: 2.255 |
Call Number |
UA @ lucian @ c:irua:89716 |
Serial |
236 |
Permanent link to this record |
|
|
|
Author |
Apolinario, S.W.S.; Peeters, F.M. |
Title |
Melting of anisotropically confined Coulomb balls |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
78 |
Issue |
2 |
Pages |
024202,1-6 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000258190200049 |
Publication Date |
2008-07-07 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
10 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2008 IF: 3.322 |
Call Number |
UA @ lucian @ c:irua:70557 |
Serial |
1986 |
Permanent link to this record |
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|
|
Author |
Apolinario, S.W.S.; Peeters, F.M. |
Title |
Melting transitions in isotropically confined three-dimensional small Coulomb clusters |
Type |
A1 Journal article |
Year |
2007 |
Publication |
Physical review : E : statistical physics, plasmas, fluids, and related interdisciplinary topics |
Abbreviated Journal |
Phys Rev E |
Volume |
76 |
Issue |
3 |
Pages |
031107,1-13 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Molecular dynamic simulations are performed to investigate the melting process of small three-dimensional clusters (i.e., systems with one and two shells) of classical charged particles trapped in an isotropic parabolic potential. The confined particles interact through a repulsive potential. We find that the ground-state configurations for systems with N=6, 12, 13, and 38 particles interacting through a Coulomb potential are magic clusters. Such magic clusters have an octahedral or icosahedral symmetry and are found to have a large stability against intrashell diffusion leading to an intershell melting transition prior to the intrashell and radial melting process. For systems with two shells a local radial melting of subshells is found at low temperatures resulting in a structural transition leading to an increased symmetry of the ordered system. Using Lindemanns criterion the different melting temperatures are determined and the influence of the screening of the interparticle interaction was investigated. A normal mode analysis is performed and some of the normal modes are found to be determinantal for the melting process. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000249785800015 |
Publication Date |
2007-09-10 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1539-3755;1550-2376; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.366 |
Times cited |
28 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.366; 2007 IF: 2.483 |
Call Number |
UA @ lucian @ c:irua:65693 |
Serial |
1990 |
Permanent link to this record |
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|
|
Author |
Araizi-Kanoutas, G.; Geessinck, J.; Gauquelin, N.; Smit, S.; Verbeek, X.H.; Mishra, S.K.; Bencok, P.; Schlueter, C.; Lee, T.-L.; Krishnan, D.; Fatermans, J.; Verbeeck, J.; Rijnders, G.; Koster, G.; Golden, M.S. |
Title |
Co valence transformation in isopolar LaCoO3/LaTiO3 perovskite heterostructures via interfacial engineering |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Physical review materials |
Abbreviated Journal |
Phys. Rev. Materials |
Volume |
4 |
Issue |
2 |
Pages |
026001 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We report charge transfer up to a single electron per interfacial unit cell across nonpolar heterointerfaces from the Mott insulator LaTiO3 to the charge transfer insulator LaCoO3. In high-quality bi- and trilayer systems grown using pulsed laser deposition, soft x-ray absorption, dichroism, and scanning transmission electron microscopy-electron energy loss spectroscopy are used to probe the cobalt-3d electron count and provide an element-specific investigation of the magnetic properties. The experiments show the cobalt valence conversion is active within 3 unit cells of the heterointerface, and able to generate full conversion to 3d7 divalent Co, which displays a paramagnetic ground state. The number of LaTiO3/LaCoO3 interfaces, the thickness of an additional, electronically insulating “break” layer between the LaTiO3 and LaCoO3, and the LaCoO3 film thickness itself in trilayers provide a trio of control knobs for average charge of the cobalt ions in LaCoO3, illustrating the efficacy of O−2p band alignment as a guiding principle for property design in complex oxide heterointerfaces. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
|
Editor |
|
Language |
|
Wos |
000513551200007 |
Publication Date |
2020-02-10 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2475-9953 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.4 |
Times cited |
13 |
Open Access |
OpenAccess |
Notes |
Nederlandse Organisatie voor Wetenschappelijk Onderzoek; Universiteit Antwerpen; Horizon 2020, 730872 ; Department of Science and Technology, Ministry of Science and Technology, SR/NM/Z-07/2015 ; Jawaharlal Nehru Centre for Advanced Scientific Research; |
Approved |
Most recent IF: 3.4; 2020 IF: NA |
Call Number |
EMAT @ emat @c:irua:167787 |
Serial |
6376 |
Permanent link to this record |
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|
Author |
Arakcheeva, A.; Pattison, P.; Chapuis, G.; Rossell, M.; Filaretov, A.; Morozov, V.; Van Tendeloo, G. |
Title |
KSm(MoO4)2, an incommensurately modulated and partially disordered scheelite-like structure |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Acta crystallographica: section B: structural science |
Abbreviated Journal |
Acta Crystallogr B |
Volume |
64 |
Issue |
Part 2 |
Pages |
160-171 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The incommensurately modulated scheelite-like KSm( MoO4)(2) structure has been refined in the monoclinic superspace group I2/b(alpha beta 0)00 by the Rietveld method on the basis of synchrotron radiation powder diffraction data. The systematic broadening of satellite reflections has been accounted for by applying anisotropic microstrain line-broadening. The microstructure has been studied by transmission electron microscopy (TEM). The partial disorder of the K and Sm cations in the A position is best approximated by a combination of harmonic and complex crenel functions with (0.952Sm + 0.048K) and (0.952K + 0.048Sm) atomic domains. This combination yields a compositional wave distribution from {KMoO4} to {SmMoO4} observed in the ab structure projection along q. The specific features of KSm(MoO4)(2) and degree of the A-cation ordering are discussed in comparison with the previously reported structure of KNd(MoO4)(2). |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Copenhagen |
Editor |
|
Language |
|
Wos |
000253992600004 |
Publication Date |
2008-03-28 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0108-7681; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
23 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:102618 |
Serial |
3539 |
Permanent link to this record |
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|
Author |
Arana, A.; Loureiro, A.L.; Barbosa, H.M.J.; Van Grieken, R.; Artaxo, P. |
Title |
Optimized energy dispersive X-ray fluorescence analysis of atmospheric aerosols collected at pristine and perturbed Amazon Basin sites |
Type |
A1 Journal article |
Year |
2014 |
Publication |
X-ray spectrometry |
Abbreviated Journal |
|
Volume |
43 |
Issue |
4 |
Pages |
228-237 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Elemental composition of aerosols is important to source apportionment studies and to understand atmospheric processes that influence aerosol composition. Energy dispersive X-ray fluorescence spectroscopy was applied for measuring the elemental composition of Amazonian atmospheric aerosols. The instrument used was a spectrometer Epsilon 5, PANalytical B. V., with tridimensional geometry that reduces the background signal with a polarized X-ray detection. The measurement conditions were optimized for low-Z elements, e. g. Mg, Al, Si, that are present at very low concentrations in the Amazon. From Na to K, our detection limits are about 50% to 75% lower than previously published results for similar instrument. Calibration was performed using Micromatter standards, except for P whose standard was produced by nebulization of an aqueous solution of KH2PO4 at our laboratory. The multi-element reference material National Institute of Standards and Technology-2783 (air particulate filter) was used for evaluating the accuracy of the calibration procedure of the 22 elements in our standard analysis routine, and the uncertainty associated with calibration procedures was evaluated. The overall performance of the instrument and validation of our measurements were assessed by comparison with results obtained from parallel analysis using particle-induced X-ray emission and another Epsilon 5 spectrometer. The elemental composition in 660 samples collected at a pristine site in the Amazon Basin and of 1416 samples collected at a site perturbed by land use change was determined. Our measurements show trace elements associated with biogenic aerosols, soil dust, biomass burning, and sea-salt, even for the very low concentrations as observed in Amazonia. Copyright (C) 2014 John Wiley & Sons, Ltd. |
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 |
000337724600006 |
Publication Date |
2014-06-09 |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0049-8246 |
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:118419 |
Serial |
8342 |
Permanent link to this record |