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Author |
Huyskens, C.; Brauns, E.; van Hoof, E.; Diels, L.; de Wever, H. |
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Title |
Validation of a supervisory control system for energy savings in membrane bioreactors |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Water research |
Abbreviated Journal |
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Volume |
45 |
Issue |
3 |
Pages |
1443-1453 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
The application of fixed operational protocols and settings for membrane bioreactors (MBR) often leads to suboptimal filtration conditions due to the dynamic nature of mixed liquor characteristics. With regard to process optimization and energy savings, the potential benefits of a dynamic control system, enabling to adapt fouling control actions (ACS outputs) in an automated way to the actual mixed liquor fouling propensity, are thus obvious. In this paper, the pilot-scale validation of such an advanced control system (ACS) is elaborated. A specific on-line fouling measurement method, the MBR-VFM (VITO Fouling Measurement), was used for the evaluation of the mixed liquors reversible fouling propensity, which was used as a primary ACS input parameter. A first series of tests with a gradual increase in complexity of the selected input and output parameters indicated the functionality of the ACS and demonstrated a substantial reduction of aeration, however sometimes at the expense of a higher fouling rate. The ACS was further fine-tuned and subsequently tested for a longer period under more dynamic operating conditions. A significant correlation was found between the reversible fouling potential measured by the MBR-VFM and the on-line permeability, indicating that the MBR-VFM is a suitable ACS input. Furthermore, an average 22% reduction in aeration flow to the membranes could be achieved without any obvious negative effect on filtration performance. This indicates that this approach is promising to optimize energy consumption in MBRs. |
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Wos |
000287054500047 |
Publication Date |
2010-11-11 |
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Series Issue |
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Edition |
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ISSN |
0043-1354; 1879-2448 |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
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Open Access |
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no |
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Call Number |
UA @ admin @ c:irua:88400 |
Serial |
8728 |
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Author |
Larraín, M.; Billen, P.; Van Passel, S. |
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Title |
The effect of plastic packaging recycling policy interventions as a complement to extended producer responsibility schemes : a partial equilibrium model |
Type |
A1 Journal article |
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Year |
2022 |
Publication |
Waste Management |
Abbreviated Journal |
Waste Manage |
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Volume |
153 |
Issue |
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Pages |
355-366 |
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Keywords |
A1 Journal article; Engineering Management (ENM); Intelligence in PRocesses, Advanced Catalysts and Solvents (iPRACS) |
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Abstract |
Extended producer responsibility (EPR) schemes have effectively increased the plastic waste that is separately collected. However, due to the structure of the recycling industry, EPR cannot increase recycling rates up to the target levels.Additional policy instruments to increase recycling rates such as recycled content targets, green dot fees bonus for recycled content, recycling targets and taxes on non-recycled plastic packaging have been discussed on a political level in the last years. However, very little research has quantitatively studied the effectiveness of these policy interventions.Using a partial equilibrium model, this paper examines the effectiveness of the implementation of the aforementioned policy instruments to increase recycling rates and the impact on different stakeholders of the value chain: plastic producers, consumers, producer responsibility organization and recyclers.Results show that direct interventions (recycled content standards and recycling targets) have the benefit of decoupling the recycling industry from external markets such as the oil market. They can be a good starting point to increase recycling, but in the long term they may be restricting by not presenting incentives to achieve recycling levels beyond the targeted amounts and by limiting technological innovation. On the contrary, eco-nomic interventions such as a green dot fee bonus or a packaging tax create economic incentives for recycling. However, these incentives are diminished by the lower perceived quality of packaging with higher recycled content levels. |
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Wos |
000868915000004 |
Publication Date |
2022-09-30 |
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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 |
0956-053x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
8.1 |
Times cited |
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Open Access |
Not_Open_Access |
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Notes |
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Approved |
Most recent IF: 8.1 |
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Call Number |
UA @ admin @ c:irua:191367 |
Serial |
7370 |
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Author |
Thomassen, G.; Van Passel, S.; Alaerts, L.; Dewulf, J. |
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Title |
Retrospective and prospective material flow analysis of the post-consumer plastic packaging waste management system in Flanders |
Type |
A1 Journal article |
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Year |
2022 |
Publication |
Waste Management |
Abbreviated Journal |
Waste Manage |
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Volume |
147 |
Issue |
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Pages |
10-21 |
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Keywords |
A1 Journal article; Engineering Management (ENM) |
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Abstract |
The post-consumer plastic packaging waste management in Flanders was analyzed by performing a retrospective material flow analysis, covering an extensive period from 1985 to 2019. In addition, a prospective material flow analysis of 32 improvement scenarios was performed, based on expected changes in the waste management system. Mass recovery rates were calculated based on different interpretations of the calculation rules. Moreover, various cascading levels were identified to differentiate between the quality level of the secondary applications. The mass recovery rate including only recycling evolved from a value of 0% in 1985 to 31% in 2019 and could be increased to 36-62% depending on the improvement scenario selected. However, the different interpretations of the calculation rules led to a variation of up to 20 and 41% on this mass recovery rates for the retrospective and prospective analysis, respectively. The introduction of monostream recycling for additional post-consumer plastic packaging flows, such as low-density polyethylene, did not lead to increasing mass recovery rates, if no differentiation for the cascading levels was made. The Belgian recycling target of 65% for 2023 will be challenging if the strictest calculation method needs to be followed or if the improvements in the Flemish postconsumer plastic packaging waste system do not follow the best-case collection scenarios under the given assumptions. To harmonize the calculation and monitoring of these targets, clear calculation rules need to be accompanied with a harmonized monitoring system over the entire waste management system. |
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Thesis |
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Wos |
000802961100002 |
Publication Date |
2022-05-17 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0956-053x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
8.1 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 8.1 |
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Call Number |
UA @ admin @ c:irua:188651 |
Serial |
7367 |
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Author |
Hoogmartens, R.; Eyckmans, J.; Van Passel, S. |
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Title |
Landfill taxes and enhanced waste management : combining valuable practices with respect to future waste streams |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Waste Management |
Abbreviated Journal |
Waste Manage |
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Volume |
55 |
Issue |
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Pages |
345-354 |
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Keywords |
A1 Journal article; Engineering Management (ENM) |
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Abstract |
Both landfill taxes and Enhanced Waste Management (EWM) practices can mitigate the scarcity issue of landfill capacity by respectively reducing landfilled waste volumes and valorising future waste streams. However, high landfill taxes might erode incentives for EWM, even though EWM creates value by valorising waste. Concentrating on Flanders (Belgium), the paper applies dynamic optimisation modelling techniques to analyse how landfill taxation and EWM can reinforce each other and how taxation schemes can be adjusted in order to foster sustainable and welfare maximising ways of processing future waste streams. Based on the Flemish simulation results, insights are offered that are generally applicable in international waste and resource management policy. As shown, the optimal Flemish landfill tax that optimises welfare in the no EWM scenario is higher than the one in the EWM scenario (93 against (sic)50/ton). This difference should create incentives for applying EWM and is driven by the positive external effects that are generated by EWM practices. In Flanders, as the current landfill tax is slightly lower than these optimal levels, the choice that can be made is to further increase taxation levels or show complete commitment to EWM. A first generally applicable insight that was found points to the fact that it is not necessarily the case that the higher the landfill tax, the more effective waste management improvements can be realised. Other insights are about providing sufficient incentives for applying EMW practices and formulating appropriate pleas in support of technological development. By these insights, this paper should provide relevant information that can assist in triggering the transition towards a resource efficient, circular economy in Europe. (C) 2016 Elsevier Ltd. All rights reserved. |
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Corporate Author |
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Wos |
000381535200036 |
Publication Date |
2016-04-05 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0956-053x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles; WoS full record; WoS citing articles |
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Impact Factor |
4.03 |
Times cited |
5 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 4.03 |
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Call Number |
UA @ admin @ c:irua:137150 |
Serial |
6222 |
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Author |
Danthurebandara, M.; Van Passel, S.; Vanderreydt, I.; Van Acker, K. |
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Title |
Assessment of environmental and economic feasibility of Enhanced Landfill Mining |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Waste Management |
Abbreviated Journal |
Waste Manage |
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Volume |
45 |
Issue |
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Pages |
434-447 |
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Keywords |
A1 Journal article; Economics; Engineering Management (ENM) |
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Abstract |
This paper addresses the environmental and economic performance of Enhanced Landfill Mining (ELFM). Based on life cycle assessment and life cycle costing, a detailed model is developed and is applied to a case study, i.e. the first ELFM project in Belgium. The environmental and economic analysis is performed in order to study the valorisation of different waste types in the landfill, such as municipal solid waste, industrial waste and total waste. We found that ELFM is promising for the case study landfill as greater environmental benefits are foreseen in several impact categories compared to the landfills current situation (the Do-nothing scenario). Among the considered processes, the thermal treatment process dominates both the environmental and economic performances of ELFM. Improvements in the electrical efficiency of thermal treatment process, the calorific value of refuse derived fuel and recovery efficiencies of different waste fractions lead the performance of ELFM towards an environmentally sustainable and economically feasible direction. Although the environmental and economic profiles of ELFM will differ from case to case, the results of this analysis can be used as a benchmark for future ELFM projects. |
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Wos |
000364796800048 |
Publication Date |
2015-02-21 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0956-053x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.03 |
Times cited |
30 |
Open Access |
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Notes |
; The authors would like to acknowledge the funding of this study by the IWT-O&O ELFM project 'Closing the Circle & Enhanced Landfill Mining as part of the Transition to Sustainable Materials Management' and the valuable discussions with Group Machiels (Belgium). ; |
Approved |
Most recent IF: 4.03; 2015 IF: 3.220 |
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Call Number |
UA @ admin @ c:irua:129878 |
Serial |
6156 |
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Author |
Kalitzova, M.; Vlakhov, E.; Marinov, Y.; Gesheva, K.; Ignatova, V.A.; Lebedev, O.; Muntele, C.; Gijbels, R. |
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Title |
Effect of high-frequency electromagnetic field on Te+-implanted (001) Si</tex> |
Type |
A1 Journal article |
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Year |
2004 |
Publication |
Vacuum: the international journal and abstracting service for vacuum science and technology |
Abbreviated Journal |
Vacuum |
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Volume |
76 |
Issue |
2-3 |
Pages |
325-328 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
The analysis of high-frequency electromagnetic field (HFEMF) effects on the microstructure and electrical properties of Te+ implanted (0 0 1) Si is reported. Cross-sectional high-resolution transmission electron microscopy (XHRTEM) demonstrates the formation of Te nanoclusters (NCs) embedded in the Si layer amorphized by implantation (a-Si) at fluences greater than or equal to 1 x 10(16) cm(-2). Post-implantation treatment with 0.45 MHz HFEMF leads to enlargement of Te NCs, their diffusion and accumulation at the a-Si surface and formation of laterally connected extended tellurium structures above the percolation threshold, appearing at an ion fluence of 1 x 10(17) cm(-2). AC electrical conductivity measurements show nearly four orders of magnitude decrease of impedance resistivity in this case, which is in good agreement with the results of our structural studies. The results obtained are discussed in terms of the two-phase isotropic spinodal structure. (C) 2004 Elsevier Ltd. All rights reserved. |
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Corporate Author |
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Place of Publication |
Oxford |
Editor |
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Language |
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Wos |
000224890100048 |
Publication Date |
2004-08-21 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0042-207X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.53 |
Times cited |
2 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.53; 2004 IF: 0.902 |
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Call Number |
UA @ lucian @ c:irua:95105 |
Serial |
814 |
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Author |
Gorji, S.; Kashiwar, A.; Mantha, L.S.; Kruk, R.; Witte, R.; Marek, P.; Hahn, H.; Kübel, C.; Scherer, T. |
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Title |
Nanowire facilitated transfer of sensitive TEM samples in a FIB |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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Volume |
219 |
Issue |
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Pages |
113075 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
We introduce a facile approach to transfer thin films and other mechanically sensitive TEM samples inside a FIB with minimal introduction of stress and bending. The method is making use of a pre-synthetized flexible freestanding Ag nanowire attached to the tip of a typical tungsten micromanipulator inside the FIB. The main advantages of this approach are the significantly reduced stress-induced bending during transfer and attachment of the TEM sample, the very short time required to attach and cut the nanowire, the operation at very low dose and ion current, and only using the e-beam for Pt deposition during the transfer of sensitive TEM samples. This results in a reduced sample preparation time and reduced exposure to the ion beam or e-beam for Pt deposition during the sample preparation and thus also reduced contamination and beam damage. The method was applied to a number of thin films and different TEM samples in order to illustrate the advantageous benefits of the concept. In particular, the technique has been successfully tested for the transfer of a thin film onto a MEMS heating chip for in situ TEM experiments. |
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Place of Publication |
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Wos |
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Publication Date |
2020-07-15 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0304-3991 |
ISBN |
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Additional Links |
UA library record |
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Impact Factor |
2.2 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 2.2; 2020 IF: 2.843 |
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Call Number |
UA @ admin @ c:irua:183618 |
Serial |
6871 |
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Author |
Leuthner, G.T.; Hummel, S.; Mangler, C.; Pennycook, T.J.; Susi, T.; Meyer, J.C.; Kotakoski, J. |
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Title |
Scanning transmission electron microscopy under controlled low-pressure atmospheres |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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Volume |
203 |
Issue |
203 |
Pages |
76-81 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Transmission electron microscopy (TEM) is carried out in vacuum to minimize the interaction of the imaging electrons with gas molecules while passing through the microscope column. Nevertheless, in typical devices, the pressure remains at 10(-7) mbar or above, providing a large number of gas molecules for the electron beam to crack, which can lead to structural changes in the sample. Here, we describe experiments carried out in a modified scanning TEM (STEM) instrument, based on the Nion UltraSTEM 100. In this instrument, the base pressure at the sample is around 2 x 10(-10 )mbar, and can be varied up to 10(-6) mbar through introduction of gases directly into the objective area while maintaining atomic resolution imaging conditions. We show that air leaked into the microscope column during the experiment is efficient in cleaning graphene samples from contamination, but ineffective in damaging the pristine lattice. Our experiments also show that exposure to O(2 )and H2O lead to a similar result, oxygen providing an etching effect nearly twice as efficient as water, presumably due to the two 0 atoms per molecule. H(2 )and N-2 environments have no influence on etching. These results show that the residual gas environment in typical TEM instruments can have a large influence on the observations, and show that chemical etching of carbon-based structures can be effectively carried out with oxygen. |
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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 |
000465021000010 |
Publication Date |
2019-02-04 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0304-3991 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.843 |
Times cited |
4 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.843 |
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Call Number |
UA @ admin @ c:irua:165937 |
Serial |
6321 |
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Author |
Susi, T.; Madsen, J.; Ludacka, U.; Mortensen, J.J.; Pennycook, T.J.; Lee, Z.; Kotakoski, J.; Kaiser, U.; Meyer, J.C. |
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Title |
Efficient first principles simulation of electron scattering factors for transmission electron microscopy |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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Volume |
197 |
Issue |
197 |
Pages |
16-22 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Electron microscopy is a powerful tool for studying the properties of materials down to their atomic structure. In many cases, the quantitative interpretation of images requires simulations based on atomistic structure models. These typically use the independent atom approximation that neglects bonding effects, which may, however, be measurable and of physical interest. Since all electrons and the nuclear cores contribute to the scattering potential, simulations that go beyond this approximation have relied on computationally highly demanding all-electron calculations. Here, we describe a new method to generate ab initio electrostatic potentials when describing the core electrons by projector functions. Combined with an interface to quantitative image simulations, this implementation enables an easy and fast means to model electron scattering. We compare simulated transmission electron microscopy images and diffraction patterns to experimental data, showing an accuracy equivalent to earlier all-electron calculations at a much lower computational cost. |
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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 |
000456311700003 |
Publication Date |
2018-11-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0304-3991 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.843 |
Times cited |
3 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.843 |
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Call Number |
UA @ admin @ c:irua:165938 |
Serial |
6296 |
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Author |
Pennycook, T.J.; Martinez, G.T.; Nellist, P.D.; Meyer, J.C. |
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Title |
High dose efficiency atomic resolution imaging via electron ptychography |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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Volume |
196 |
Issue |
196 |
Pages |
131-135 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Radiation damage places a fundamental limitation on the ability of microscopy to resolve many types of materials at high resolution. Here we evaluate the dose efficiency of phase contrast imaging with electron ptychography. The method is found to be far more resilient to temporal incoherence than conventional and spherical aberration optimized phase contrast imaging, resulting in significantly greater clarity at a given dose. This robustness is explained by the presence of achromatic lines in the four dimensional ptychographic dataset. |
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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 |
000451180800018 |
Publication Date |
2018-10-18 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0304-3991 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.843 |
Times cited |
1 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.843 |
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Call Number |
UA @ admin @ c:irua:165939 |
Serial |
6301 |
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Author |
Grieb, T.; Tewes, M.; Schowalter, M.; Müller-Caspary, K.; Krause, F.F.; Mehrtens, T.; Hartmann, J.-M.; Rosenauer, A. |
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Title |
Quantitative HAADF STEM of SiGe in presence of amorphous surface layers from FIB preparation |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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Volume |
184 |
Issue |
B |
Pages |
29-36 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
<script type='text/javascript'>document.write(unpmarked('The chemical composition of four Si1-xGex layers grown on silicon was determined from quantitative scanning transmission electron microscopy (STEM). The chemical analysis was performed by a comparison of the high-angle annular dark field (HAADF) intensity with multislice simulations. It could be shown that amorphous surface layers originating from the preparation process by focused-ion beam (FIB) at 30 kV have a strong influence on the quantification: the local specimen thickness is overestimated by approximately a factor of two, and the germanium concentration is substantially underestimated. By means of simulations, the effect of amorphous surface layers on the HAADF intensity of crystalline silicon and germanium is investigated. Based on these simulations, a method is developed to analyze the experimental HAADF-STEM images by taking the influence of the amorphous layers into account which is done by a reduction of the intensities by multiplication with a constant factor. This suggested modified HAADF analysis gives germanium concentrations which are in agreement with the nominal values. The same TEM lamella was treated with low-voltage ion milling which removed the amorphous surface layers completely. The results from subsequent quantitative HAADF analyses are in agreement with the nominal concentrations which validates the applicability of the used frozen-lattice based multislice simulations to describe the HAADF scattering of Si1-xGex in STEM. (C) 2017 Elsevier B.V. All rights reserved.')); |
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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 |
000417779800004 |
Publication Date |
2017-10-14 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.843 |
Times cited |
7 |
Open Access |
Not_Open_Access |
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| |
Notes |
; This work was supported by the German Research Foundation (DFG) under Contract No. RO2057/11-1. ; |
Approved |
Most recent IF: 2.843 |
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| |
Call Number |
UA @ lucian @ c:irua:148500 |
Serial |
4893 |
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| Permanent link to this record |
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Author |
Vatanparast, M.; Egoavil, R.; Reenaas, T.W.; Verbeeck, J.; Holmestad, R.; Vullum, P.E. |
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Title |
Bandgap measurement of high refractive index materials by off-axis EELS |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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| |
Volume |
182 |
Issue |
|
Pages |
92-98 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
In the present work Cs aberration corrected and monochromated scanning transmission electron microscopy electron energy loss spectroscopy (STEM-EELS) has been used to explore experimental setups that allow bandgaps of high refractive index materials to be determined. Semi-convergence and collection angles in the mu rad range were combined with off-axis or dark field EELS to avoid relativistic losses and guided light modes in the low loss range to contribute to the acquired EEL spectra. Off-axis EELS further supressed the zero loss peak and the tail of the zero loss peak. The bandgap of several GaAs-based materials were successfully determined by simple regression analyses of the background subtracted EEL spectra. The presented set-up does not require that the acceleration voltage is set to below the. Cerenkov limit and can be applied over the entire acceleration voltage range of modern TEMs and for a wide range of specimen thicknesses. (C) 2017 Elsevier B.V. All rights reserved. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000413436500013 |
Publication Date |
2017-06-21 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.843 |
Times cited |
3 |
Open Access |
Not_Open_Access |
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Notes |
; The authors would like to thank Professor Shu Min Wang and Mahdad Sadeghi at the Nanofabrication Laboratory at Chalmers University, Sweden for providing the samples. The Norwegian Research Council is acknowledged for funding the HighQ-IB project under contract no. 10415201. M.V. and T.W.R. acknowledge funding from the EEA Financial Mechanism 2009-2014 under the project contract no 23SEE/30.06.2014. The research leading to these results has received funding from the European Union Seventh Framework Programme under Grant Agreement 312483 – ESTEEM2(Integrated Infrastructure Initiative-I3) through the system of transnational access. R.E. and J.V. acknowledge funding from GOA project “Solarpaint” of the University of Antwerp. ; |
Approved |
Most recent IF: 2.843 |
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| |
Call Number |
UA @ lucian @ c:irua:146639UA @ admin @ c:irua:146639 |
Serial |
4778 |
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Author |
Grieb, T.; Krause, F.F.; Mahr, C.; Zillmann, D.; Müller-Caspary, K.; Schowalter, M.; Rosenauer, A. |
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Title |
Optimization of NBED simulations for disc-detection measurements |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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| |
Volume |
181 |
Issue |
|
Pages |
50-60 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Nano-beam electron diffraction (NBED) is a method which can be applied to measure lattice strain and polarisation fields in strained layer heterostructures and transistors. To investigate precision, accuracy and spatial resolution of such measurements in dependence of properties of the specimen as well as electron optical parameters, simulations of NBED patterns are required which allow to predict the result of common disc-detection algorithms. In this paper we demonstrate by focusing on the detection of the central disc in crystalline silicon that such simulations require to take several experimental characteristics into account in order to obtain results which are comparable to those from experimental NBED patterns. These experimental characteristics are the background intensity, the presence of Poisson noise caused by electron statistics and blurring caused by inelastic scattering and by the transfer quality of the microscope camera. By means of these optimized simulations, different effects of specimen properties on disc detection – such as strain, surface morphology and compositional changes on the nanometer scale – are investigated and discussed in the context of misinterpretation in experimental NBED evaluations. It is shown that changes in surface morphology and chemical composition lead to measured shifts of the central disc in the NBED pattern of tens to hundreds of grad. These shifts are of the same order of magnitude or even larger than shifts that could be caused by an electric polarisation field in the range of MV/cm. (C) 2017 Elsevier B.V. All rights reserved. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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| |
Language |
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Wos |
000411170800006 |
Publication Date |
2017-05-03 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
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| |
ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.843 |
Times cited |
6 |
Open Access |
Not_Open_Access |
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| |
Notes |
; This work was supported by the German Research Foundation (DFG) under Contract No. R02057/11-1, R02057/4-2 and MU3660/1-1. ; |
Approved |
Most recent IF: 2.843 |
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| |
Call Number |
UA @ lucian @ c:irua:146725 |
Serial |
4792 |
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| Permanent link to this record |
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Author |
Javon, E.; Lubk; Cours, R.; Reboh, S.; Cherkashin, N.; Houdellier, F.; Gatel, C.; Hytch, M.J. |
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Title |
Dynamical effects in strain measurements by dark-field electron holography |
Type |
A1 Journal article |
| |
Year |
2014 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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| |
Volume |
147 |
Issue |
|
Pages |
70-85 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Here, we study the effect of dynamic scattering on the projected geometric phase and strain maps reconstructed using dark-field electron holography (DFEH) for non-uniformly strained crystals. The investigated structure consists of a {SiGe/Si} superlattice grown on a (001)-Si substrate. The three dimensional strain held within the thin TEM lamella is modelled by the finite element method. The observed projected strain is simulated in two ways by multiplying the strain at each depth in the crystal by a weighting function determined from a recently developed analytical two-beam dynamical theory, and by simply taking the average value. We demonstrate that the experimental results need to be understood in terms of the dynamical theory and good agreement is found between the experimental and simulated results. Discrepancies do remain for certain cases and are likely to be from an imprecision in the actual two-beam diffraction conditions, notably the deviation parameter, and points to limitations in the 2-beam approximation. Finally, a route towards a 3D reconstruction of strain fields is proposed. (C) 2014 Elsevier B.V. All rights reserved. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000343157400009 |
Publication Date |
2014-07-02 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0304-3991; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.843 |
Times cited |
10 |
Open Access |
|
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Notes |
|
Approved |
Most recent IF: 2.843; 2014 IF: 2.436 |
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Call Number |
UA @ lucian @ c:irua:121108 |
Serial |
769 |
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| Permanent link to this record |
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Author |
Niermann, T.; Verbeeck, J.; Lehmann, M. |
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Title |
Creating arrays of electron vortices |
Type |
A1 Journal article |
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Year |
2014 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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| |
Volume |
136 |
Issue |
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Pages |
165-170 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We demonstrate the production of an ordered array of electron vortices making use of an electron optical setup consisting of two electrostatic biprisms. The biprism filaments are oriented nearly orthogonal with respect to each other in a transmission electron microscope. Matching the position of the filaments, we can choose to form different topological features in the electron wave. We outline the working principle of the setup and demonstrate fist experimental results. This setup partially bridges the gap between angular momentum carried by electron spin, which is intrinsic and therefore present in any position of the wave, and angular momentum carried by the vortex character of the wave, which can be extrinsic depending on the axis around which it is measured. (C) 2013 Elsevier B.V. All rights reserved. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000327884700021 |
Publication Date |
2013-10-15 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.843 |
Times cited |
9 |
Open Access |
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Notes |
FP7; Countatoms; Vortex ECASJO_; |
Approved |
Most recent IF: 2.843; 2014 IF: 2.436 |
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Call Number |
UA @ lucian @ c:irua:112837UA @ admin @ c:irua:112837 |
Serial |
538 |
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Author |
Béché, A.; Rouviere, J.L.; Barnes, J.P.; Cooper, D. |
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Title |
Strain measurement at the nanoscale : comparison between convergent beam electron diffraction, nano-beam electron diffraction, high resolution imaging and dark field electron holography |
Type |
A1 Journal article |
| |
Year |
2013 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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| |
Volume |
131 |
Issue |
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Pages |
10-23 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Convergent beam electron diffraction (CBED), nano-beam electron diffraction (NBED or NBD), high resolution imaging (HRTEM and HRSTEM) and dark field electron holography (DFEH or HoloDark) are five TEM based techniques able to quantitatively measure strain at the nanometer scale. In order to demonstrate the advantages and disadvantages of each technique, two samples composed of epitaxial silicon-germanium layers embedded in a silicon matrix have been investigated. The five techniques are then compared in terms of strain precision and accuracy, spatial resolution, field of view, mapping abilities and ease of performance and analysis. (C) 2013 Elsevier By. All rights reserved. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000322631200002 |
Publication Date |
2013-04-06 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.843 |
Times cited |
73 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 2.843; 2013 IF: 2.745 |
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Call Number |
UA @ lucian @ c:irua:109774 |
Serial |
3171 |
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| Permanent link to this record |
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Author |
Wang, A.; Chen, F.R.; Van Aert, S.; van Dyck, D. |
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Title |
Direct structure inversion from exit waves : part 2 : a practical example |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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| |
Volume |
116 |
Issue |
|
Pages |
77-85 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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Abstract |
This paper is the second part of a two-part paper on direct structure inversion from exit waves. In the first part, a method has been proposed to quantitatively determine structure parameters with atomic resolution such as atom column positions, surface profile and the number of atoms in the atom columns. In this part, the theory will be demonstrated by means of a Au[110] exit wave reconstructed from a set of focal-series images. The procedures to analyze the experimentally reconstructed exit wave in terms of quantitative structure information are described in detail. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000304473700011 |
Publication Date |
2012-03-28 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.843 |
Times cited |
8 |
Open Access |
|
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Notes |
Fwo |
Approved |
Most recent IF: 2.843; 2012 IF: 2.470 |
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Call Number |
UA @ lucian @ c:irua:96660 |
Serial |
724 |
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| Permanent link to this record |
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Author |
Tan, H.; Verbeeck, J.; Abakumov, A.; Van Tendeloo, G. |
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Title |
Oxidation state and chemical shift investigation in transition metal oxides by EELS |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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| |
Volume |
116 |
Issue |
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Pages |
24-33 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Transition metal L2,3 electron energy-loss spectra for a wide range of V-, Mn- and Fe-based oxides were recorded and carefully analyzed for their correlation with the formal oxidation states of the transition metal ions. Special attention is paid to obtain an accurate energy scale which provides absolute energy positions for all core-loss edges. The white-line ratio method, chemical shift method, ELNES fitting method, two-parameter method and other methods are compared and their validity is discussed. Both the ELNES fitting method and the chemical shift method have the advantage of a wide application range and good consistency but require special attention to accurately measure the core-loss edge position. The obtained conclusions are of fundamental importance, e.g., for obtaining atomic resolution oxidation state information in modern experiments. |
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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 |
000304473700004 |
Publication Date |
2012-03-10 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.843 |
Times cited |
413 |
Open Access |
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Notes |
Fwo |
Approved |
Most recent IF: 2.843; 2012 IF: 2.470 |
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Call Number |
UA @ lucian @ c:irua:96959UA @ admin @ c:irua:96959 |
Serial |
2541 |
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| Permanent link to this record |
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Author |
Lobato, I.; van Dyck, D. |
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Title |
Improved multislice calculations for including higher-order Laue zones effects |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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| |
Volume |
119 |
Issue |
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Pages |
63-71 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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Abstract |
A new method for including higher-order Laue zones (HOLZs) effects in an efficient way in electron scattering simulations has been developed and tested by detail calculations. The calculated results by the conventional multislice (CMS) method and the improved conventional multislice (ICMS) method using a large dynamical aperture to avoid numerical errors are compared with accurate results. We have found that the zero-order Laue zones (ZOLZs) reflection cannot be properly described only using the projected potential in the whole unit cell; in general, we need to subslice the electrostatic potential inside the unit cell. It is shown that the ICMS method has higher accuracy than the CMS method for the calculation of the ZOLZ, HOLZ and Pseudo-HOLZ reflections. Hence, ICMS method allows to use a larger slice thickness than the CMS method and reduces the calculation time. (C) 2012 Elsevier B.V. All rights reserved. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000308079200011 |
Publication Date |
2012-01-14 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.843 |
Times cited |
6 |
Open Access |
|
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| |
Notes |
|
Approved |
Most recent IF: 2.843; 2012 IF: 2.470 |
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Call Number |
UA @ lucian @ c:irua:101902 |
Serial |
1567 |
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| Permanent link to this record |
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Author |
Roelandts, T.; Batenburg, K.J.; Biermans, E.; Kübel, C.; Bals, S.; Sijbers, J. |
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Title |
Accurate segmentation of dense nanoparticles by partially discrete electron tomography |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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| |
Volume |
114 |
Issue |
|
Pages |
96-105 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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Abstract |
Accurate segmentation of nanoparticles within various matrix materials is a difficult problem in electron tomography. Due to artifacts related to image series acquisition and reconstruction, global thresholding of reconstructions computed by established algorithms, such as weighted backprojection or SIRT, may result in unreliable and subjective segmentations. In this paper, we introduce the Partially Discrete Algebraic Reconstruction Technique (PDART) for computing accurate segmentations of dense nanoparticles of constant composition. The particles are segmented directly by the reconstruction algorithm, while the surrounding regions are reconstructed using continuously varying gray levels. As no properties are assumed for the other compositions of the sample, the technique can be applied to any sample where dense nanoparticles must be segmented, regardless of the surrounding compositions. For both experimental and simulated data, it is shown that PDART yields significantly more accurate segmentations than those obtained by optimal global thresholding of the SIRT reconstruction. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000301954300011 |
Publication Date |
2012-01-06 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.843 |
Times cited |
34 |
Open Access |
|
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| |
Notes |
Fwo |
Approved |
Most recent IF: 2.843; 2012 IF: 2.470 |
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| |
Call Number |
UA @ lucian @ c:irua:97710 |
Serial |
52 |
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| Permanent link to this record |
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Author |
Wang, A.; Van Aert, S.; Goos, P.; van Dyck, D. |
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Title |
Precision of three-dimensional atomic scale measurements from HRTEM images : what are the limits? |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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| |
Volume |
114 |
Issue |
|
Pages |
20-30 |
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Keywords |
A1 Journal article; Engineering Management (ENM); Electron microscopy for materials research (EMAT); Vision lab |
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Abstract |
In this paper, we investigate to what extent high resolution transmission electron microscopy images can be used to measure the mass, in terms of thickness, and surface profile, corresponding to the defocus offset, of an object at the atomic scale. Therefore, we derive an expression for the statistical precision with which these object parameters can be estimated in a quantitative analysis. Evaluating this expression as a function of the microscope settings allows us to derive the optimal microscope design. Acquiring three-dimensional structure information in terms of thickness turns out to be much more difficult than obtaining two-dimensional information on the projected atom column positions. The attainable precision is found to be more strongly affected by processes influencing the image contrast, such as phonon scattering, than by the specific choice of microscope settings. For a realistic incident electron dose, it is expected that atom columns can be distinguished with single atom sensitivity up to a thickness of the order of the extinction distance. A comparable thickness limit is determined to measure surface steps of one atom. An increase of the electron dose shifts the limiting thickness upward due to an increase in the signal-to-noise ratio. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000301954300003 |
Publication Date |
2012-01-06 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.843 |
Times cited |
5 |
Open Access |
|
|
| |
Notes |
Fwo |
Approved |
Most recent IF: 2.843; 2012 IF: 2.470 |
|
| |
Call Number |
UA @ lucian @ c:irua:94116 |
Serial |
2692 |
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| Permanent link to this record |
| |
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| |
|
Author |
Goris, B.; van den Broek, W.; Batenburg, K.J.; Heidari Mezerji, H.; Bals, S. |
|
| |
Title |
Electron tomography based on a total variation minimization reconstruction technique |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
| |
Volume |
113 |
Issue |
|
Pages |
120-130 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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| |
Abstract |
The 3D reconstruction of a tilt series for electron tomography is mostly carried out using the weighted backprojection (WBP) algorithm or using one of the iterative algorithms such as the simultaneous iterative reconstruction technique (SIRT). However, it is known that these reconstruction algorithms cannot compensate for the missing wedge. Here, we apply a new reconstruction algorithm for electron tomography, which is based on compressive sensing. This is a field in image processing specialized in finding a sparse solution or a solution with a sparse gradient to a set of ill-posed linear equations. Therefore, it can be applied to electron tomography where the reconstructed objects often have a sparse gradient at the nanoscale. Using a combination of different simulated and experimental datasets, it is shown that missing wedge artefacts are reduced in the final reconstruction. Moreover, it seems that the reconstructed datasets have a higher fidelity and are easier to segment in comparison to reconstructions obtained by more conventional iterative algorithms. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
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| |
Language |
|
Wos |
000300554400006 |
Publication Date |
2011-11-14 |
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| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.843 |
Times cited |
171 |
Open Access |
|
|
| |
Notes |
Fwo |
Approved |
Most recent IF: 2.843; 2012 IF: 2.470 |
|
| |
Call Number |
UA @ lucian @ c:irua:93637 |
Serial |
987 |
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| Permanent link to this record |
| |
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| |
|
Author |
Wang, A.; Chen, F.R.; Van Aert, S.; van Dyck, D. |
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| |
Title |
A method to determine the local surface profile from reconstructed exit waves |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
| |
Volume |
111 |
Issue |
8 |
Pages |
1352-1359 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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| |
Abstract |
Reconstructed exit waves are useful to quantify unknown structure parameters such as the position and composition of the atom columns at atomic scale. Existing techniques provide a complex wave in a flat plane which is close to the plane where the electrons leave the atom columns. However, due to local deviation in the flatness of the exit surface, there will be an offset between the plane of reconstruction and the actual exit of a specific atom column. Using the channelling theory, it has been shown that this defocus offset can in principle be determined atom column-by-atom column. As such, the surface roughness could be quantified at atomic scale. However, the outcome strongly depends on the initial plane of reconstruction especially in a crystalline structure. If this plane is further away from the true exit, the waves of the atom columns become delocalized and interfere mutually which strongly complicates the interpretation of the exit wave in terms of the local structure. In this paper, we will study the delocalization with defocus using the channelling theory in a more systematic way. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
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| |
Language |
|
Wos |
000300461100049 |
Publication Date |
2011-05-03 |
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| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.843 |
Times cited |
3 |
Open Access |
|
|
| |
Notes |
Fwo |
Approved |
Most recent IF: 2.843; 2011 IF: 2.471 |
|
| |
Call Number |
UA @ lucian @ c:irua:88941 |
Serial |
2017 |
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| Permanent link to this record |
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| |
|
Author |
Goris, B.; Bals, S.; van den Broek, W.; Verbeeck, J.; Van Tendeloo, G. |
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| |
Title |
Exploring different inelastic projection mechanisms for electron tomography |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
| |
Volume |
111 |
Issue |
8 |
Pages |
1262-1267 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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| |
Abstract |
Several different projection mechanisms that all make use of inelastically scattered electrons are used for electron tomography. The advantages and the disadvantages of these methods are compared to HAADFSTEM tomography, which is considered as the standard electron tomography technique in materials science. The different inelastic setups used are energy filtered transmission electron microscopy (EFTEM), thickness mapping based on the log-ratio method and bulk plasmon mapping. We present a comparison that can be used to select the best inelastic signal for tomography, depending on different parameters such as the beam stability and nature of the sample. The appropriate signal will obviously also depend on the exact information which is requested. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
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| |
Language |
|
Wos |
000300461100039 |
Publication Date |
2011-03-07 |
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| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.843 |
Times cited |
21 |
Open Access |
|
|
| |
Notes |
Fwo; Iap; Esteem 026019 |
Approved |
Most recent IF: 2.843; 2011 IF: 2.471 |
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| |
Call Number |
UA @ lucian @ c:irua:91260UA @ admin @ c:irua:91260 |
Serial |
1151 |
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| Permanent link to this record |
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| |
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Author |
Verbeeck, J.; Bertoni, G.; Lichte, H. |
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| |
Title |
A holographic biprism as a perfect energy filter? |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
| |
Volume |
111 |
Issue |
7 |
Pages |
887-893 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
It has often been stated that a holographic biprism represents a near perfect energy filter and only elastically scattered electrons can participate in the interference fringes. This is based on the assumption that the reference wave does not contain inelastically scattered electrons. In this letter we show that this is not exactly true because of the delocalised inelastic interaction of the reference wave with the sample. We experimentally and theoretically show that inelastic scattering plays a role in the fringe formation, but it is shown that this contribution is small and can usually be neglected in practice. (C) 2011 Elsevier B.V. All rights reserved. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
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Place of Publication |
Amsterdam |
Editor |
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| |
Language |
|
Wos |
000300461000021 |
Publication Date |
2011-02-05 |
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| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.843 |
Times cited |
13 |
Open Access |
|
|
| |
Notes |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 2.843; 2011 IF: 2.471 |
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| |
Call Number |
UA @ lucian @ c:irua:97250UA @ admin @ c:irua:97250 |
Serial |
1482 |
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| Permanent link to this record |
| |
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| |
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Author |
Xu, Q.; Zandbergen, H.W.; van Dyck, D. |
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| |
Title |
Applying an information transmission approach to extract valence electron information from reconstructed exit waves |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
| |
Volume |
111 |
Issue |
7 |
Pages |
912-919 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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| |
Abstract |
The knowledge of the valence electron distribution is essential for understanding the properties of materials. However this information is difficult to obtain from HREM images because it is easily obscured by the large scattering contribution of core electrons and by the strong dynamical scattering process. In order to develop a sensitive method to extract the information of valence electrons, we have used an information transmission approach to describe the electron interaction with the object. The scattered electron wave is decomposed in a set of basic functions, which are the eigen functions of the Hamiltonian of the projected electrostatic object potential. Each basic function behaves as a communication channel that transfers the information of the object with its own transmission characteristic. By properly combining the components of the different channels, it is possible to design a scheme to extract the information of valence electron distribution from a series of exit waves. The method is described theoretically and demonstrated by means of computer simulations. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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| |
Language |
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Wos |
000300461000024 |
Publication Date |
2011-02-02 |
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| |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.843 |
Times cited |
1 |
Open Access |
|
|
| |
Notes |
Fwo |
Approved |
Most recent IF: 2.843; 2011 IF: 2.471 |
|
| |
Call Number |
UA @ lucian @ c:irua:93623 |
Serial |
146 |
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| Permanent link to this record |
| |
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| |
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Author |
Heidari Mezerji, H.; van den Broek, W.; Bals, S. |
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| |
Title |
A practical method to determine the effective resolution in incoherent experimental electron tomography |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
| |
Volume |
111 |
Issue |
5 |
Pages |
330-336 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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| |
Abstract |
It is not straightforward to determine resolution for a 3D reconstruction when performing an electron tomography experiment. Different contributions such as missing wedge and misalignment add up and often influence the final resolution in an anisotropic manner. The conventional resolution measures can not be used for all of the reconstruction techniques, especially for iterative techniques which are more commonly used for electron tomography in materials science. Here we define a quantitative resolution measure that determines the resolution in three orthogonal directions of the reconstruction. As an application we use this measure to determine the optimum number of simultaneous iterative reconstruction technique (SIRT) iterations to reconstruct the gold nanoparticles, based on a high angle annular dark field STEM (HAADF-STEM) tilt series. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
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| |
Language |
|
Wos |
000289396900005 |
Publication Date |
2011-01-24 |
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| |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.843 |
Times cited |
26 |
Open Access |
|
|
| |
Notes |
Esteem 026019; Fwo |
Approved |
Most recent IF: 2.843; 2011 IF: 2.471 |
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| |
Call Number |
UA @ lucian @ c:irua:87606 |
Serial |
2688 |
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| Permanent link to this record |
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| |
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Author |
Béché, A.; Rouvière, J.L.; Barnes, J.P.; Cooper, D. |
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| |
Title |
Dark field electron holography for strain measurement |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
| |
Volume |
111 |
Issue |
3 |
Pages |
227-238 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Dark field electron holography is a new TEM-based technique for measuring strain with nanometer scale resolution. Here we present the procedure to align a transmission electron microscope and obtain dark field holograms as well as the theoretical background necessary to reconstruct strain maps from holograms. A series of experimental parameters such as biprism voltage, sample thickness, exposure time, tilt angle and choice of diffracted beam are then investigated on a silicon-germanium layer epitaxially embedded in a silicon matrix in order to obtain optimal dark field holograms over a large field of view with good spatial resolution and strain sensitivity. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Amsterdam |
Editor |
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| |
Language |
|
Wos |
000288638200007 |
Publication Date |
2010-12-01 |
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| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.843 |
Times cited |
31 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 2.843; 2011 IF: 2.471 |
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| |
Call Number |
UA @ lucian @ c:irua:136368 |
Serial |
4496 |
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| Permanent link to this record |
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| |
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Author |
van den Broek, W.; Van Aert, S.; Goos, P.; van Dyck, D. |
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| |
Title |
Throughput maximization of particle radius measurements by balancing size and current of the electron probe |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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| |
Volume |
111 |
Issue |
7 |
Pages |
940-947 |
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| |
Keywords |
A1 Journal article; Engineering Management (ENM); Electron microscopy for materials research (EMAT); Vision lab |
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| |
Abstract |
In thispaperweinvestigatewhichprobesizemaximizesthethroughputwhenmeasuringtheradiusof nanoparticlesinhighangleannulardarkfieldscanningtransmissionelectronmicroscopy(HAADFSTEM). The sizeandthecorrespondingcurrentoftheelectronprobedeterminetheprecisionoftheestimateofa particlesradius.Maximizingthroughputmeansthatamaximumnumberofparticlesshouldbeimaged withinagiventimeframe,sothataprespecifiedprecisionisattained.WeshowthatBayesianstatistical experimentaldesignisaveryusefulapproachtodeterminetheoptimalprobesizeusingacertainamount of priorknowledgeaboutthesample.Thedependenceoftheoptimalprobesizeonthedetectorgeometry and thediameter,variabilityandatomicnumberoftheparticlesisinvestigated.Anexpressionforthe optimalprobesizeintheabsenceofanykindofpriorknowledgeaboutthespecimenisderivedaswell. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
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| |
Language |
|
Wos |
000300461000026 |
Publication Date |
2010-11-25 |
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| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.843 |
Times cited |
7 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 2.843; 2011 IF: 2.471 |
|
| |
Call Number |
UA @ lucian @ c:irua:89657 |
Serial |
3659 |
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| Permanent link to this record |
| |
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| |
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Author |
Van Aert, S.; Chen, J.H.; van Dyck, D. |
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| |
Title |
Linear versus non-linear structural information limit in high-resolution transmission electron microscopy |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
| |
Volume |
110 |
Issue |
11 |
Pages |
1404-1410 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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| |
Abstract |
A widely used performance criterion in high-resolution transmission electron microscopy (HRTEM) is the information limit. It corresponds to the inverse of the maximum spatial object frequency that is linearly transmitted with sufficient intensity from the exit plane of the object to the image plane and is limited due to partial temporal coherence. In practice, the information limit is often measured from a diffractogram or from Young's fringes assuming a weak phase object scattering beyond the inverse of the information limit. However, for an aberration corrected electron microscope, with an information limit in the sub-angstrom range, weak phase objects are no longer applicable since they do not scatter sufficiently in this range. Therefore, one relies on more strongly scattering objects such as crystals of heavy atoms observed along a low index zone axis. In that case, dynamical scattering becomes important such that the non-linear and linear interaction may be equally important. The non-linear interaction may then set the experimental cut-off frequency observed in a diffractogram. The goal of this paper is to quantify both the linear and the non-linear information transfer in terms of closed form analytical expressions. Whereas the cut-off frequency set by the linear transfer can be directly related with the attainable resolution, information from the non-linear transfer can only be extracted using quantitative, model-based methods. In contrast to the historic definition of the information limit depending on microscope parameters only, the expressions derived in this paper explicitly incorporate their dependence on the structure parameters as well. In order to emphasize this dependence and to distinguish from the usual information limit, the expressions derived for the inverse cut-off frequencies will be referred to as the linear and non-linear structural information limit. The present findings confirm the well-known result that partial temporal coherence has different effects on the transfer of the linear and non-linear terms, such that the non-linear imaging contributions are damped less than the linear imaging contributions at high spatial frequencies. This will be important when coherent aberrations such as spherical aberration and defocus are reduced. |
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| |
Address |
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| |
Corporate Author |
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Thesis |
|
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| |
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
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| |
Language |
|
Wos |
000282562100008 |
Publication Date |
2010-07-15 |
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| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.843 |
Times cited |
6 |
Open Access |
|
|
| |
Notes |
Fwo |
Approved |
Most recent IF: 2.843; 2010 IF: 2.063 |
|
| |
Call Number |
UA @ lucian @ c:irua:83689 |
Serial |
1821 |
|
| Permanent link to this record |
