Records |
Author |
Morsdorf, L.; Kashiwar, A.; Kübel, C.; Tasan, C.C. |
Title |
Carbon segregation and cementite precipitation at grain boundaries in quenched and tempered lath martensite |
Type |
A1 Journal article |
Year |
2023 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Materials science and engineering: part A: structural materials: properties, microstructure and processing |
Abbreviated Journal |
|
Volume |
862 |
Issue |
|
Pages |
144369-21 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Tempering is widely applied to make carbon atoms beneficially rearrange in high strength steel microstructures after quenching; though the nano-scale interaction of carbon atoms with crystallographic defects is hard to experimentally observe. To improve, we investigate the redistribution of carbon atoms along martensite grain boundaries in a quenched and tempered low carbon steel. We observe the tempering-induced microstructural evolution by in-situ heating in a transmission electron microscope (TEM) and by compositional analysis through atom probe tomography (APT). Probe volumes for APT originate from a single martensite packet but in different tempering conditions, which is achieved via a sequential lift-out with in-between tempering treatments. The complementary use of TEM and APT provides crystallographic as well as chemical information on carbon segregation and subsequent carbide precipitation at martensite grain boundaries. The results show that the amount of carbon segregation to martensite grain boundaries is influenced by the boundary type, e.g. low-angle lath or high-angle block boundaries. Also, the growth behavior of cementite precipitates from grain boundary nucleation sites into neighboring martensite grains differs at low- and high-angle grain boundaries. This is due to the crystallographic constraints arising from the semi-coherent orientation relationship between cementite and adjacent martensite. We also show that slower quenching stabilizes thin retained austenite films between martensite grains because of enhanced carbon segregation during cooling. Finally, we demonstrate the effect of carbon redistribution along martensite grain boundaries on the mechanical properties. Here, we compare micro-scale Vickers hardness results from boundary-containing probe volumes to nanoindentation results from pure bulk martensite (boundary-free) probe volumes. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000905165700001 |
Publication Date |
2022-12-07 |
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 |
0921-5093 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.4 |
Times cited |
|
Open Access |
Not_Open_Access |
Notes |
|
Approved |
Most recent IF: 6.4; 2023 IF: 3.094 |
Call Number |
UA @ admin @ c:irua:192279 |
Serial |
7285 |
Permanent link to this record |
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Author |
Biró, L.P.; Khanh, N.Q.; Vértesy, Z.; Horváth, Z.E.; Osváth, Z.; Koós, A.; Gyulai, J.; Kocsonya, A.; Kónya, Z.; Zhang, X.B.; Van Tendeloo, G.; Fonseca, A.; Nagy, J.B.; |
Title |
Catalyst traces and other impurities in chemically purified carbon nanotubes grown by CVD |
Type |
A1 Journal article |
Year |
2002 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Materials science and engineering: part C: biomimetic materials
T2 – EMRS Spring Meeting, JUN 05-08, 2001, STRASBOURG, FRANCE |
Abbreviated Journal |
Mat Sci Eng C-Mater |
Volume |
19 |
Issue |
1-2 |
Pages |
9-13 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Multiwall carbon nanotubes grown by the catalytic decomposition of acetylene over supported Co catalyst were subjected to wet and dry oxidation in order to remove the unwanted products and the catalyst traces. The effects of the purification treatment on the Co content was monitored by physical methods: Rutherford Backscattering Spectrometry (RBS). Particle Induced X-Ray Emission (PIXE) and X-Ray Fluorescence (XRF). The purified products were investigated by microscopic methods: TEM. Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS) and STM. The KMnO4/H2SO4 aqueous oxidation procedure was found to be effective in reducing the Co content while damaging only moderately the outer wall of the nanotubes. Treatment in HNO3/H2SO4 yields a bucky-paper like product and produces the increase of the Si and S content of the sample. (C) 2002 Elsevier Science B.V. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lausanne |
Editor |
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Language |
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Wos |
000173080700003 |
Publication Date |
2002-07-25 |
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 |
0928-4931; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.164 |
Times cited |
36 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 4.164; 2002 IF: 0.734 |
Call Number |
UA @ lucian @ c:irua:102835 |
Serial |
289 |
Permanent link to this record |
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|
Author |
Khalil-Allafi, J.; Amin-Ahmadi, B.; Zare, M. |
Title |
Biocompatibility and corrosion behavior of the shape memory NiTi alloy in the physiological environments simulated with body fluids for medical applications |
Type |
A1 Journal article |
Year |
2010 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Materials science and engineering: part C: biomimetic materials |
Abbreviated Journal |
Mat Sci Eng C-Mater |
Volume |
30 |
Issue |
8 |
Pages |
1112-1117 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Due to unique properties of NiTi shape memory alloys such as high corrosion resistance, biocompatibility, super elasticity and shape memory behavior, NiTi shape memory alloys are suitable materials for medical applications. Although TiO2 passive layer in these alloys can prevent releasing of nickel to the environment, high nickel content and stability of passive layer in these alloys are very debatable subjects. In this study a NiTi shape memory alloy with nominal composition of 50.7 atom% Ni was investigated by corrosion tests. Electrochemical tests were performed in two physiological environments of Ringer solution and NaCl 0.9% solution. Results indicate that the breakdown potential of the NiTi alloy in NaCl 0.9% solution is higher than that in Ringer solution. The results of Scanning Electron Microscope (SEM) reveal that low pitting corrosion occurred in Ringer solution compared with NaCl solution at potentiostatic tests. The pH value of the solutions increases after the electrochemical tests. The existence of hydride products in the X-ray diffraction analysis confirms the decrease of the concentration of hydrogen ion in solutions. Topographical evaluations show that corrosion products are nearly same in all samples. The biocompatibility tests were performed by reaction of mouse fibroblast cells (L929). The growth and development of cells for different times were measured by numbering the cells or statistics investigations. The figures of cells for different times showed natural growth of cells. The different of the cell numbers between the test specimen and control specimen was negligible; therefore it may be concluded that the NiTi shape memory alloy is not toxic in the physiological environments simulated with body fluids. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Lausanne |
Editor |
|
Language |
|
Wos |
000282905600006 |
Publication Date |
2010-06-23 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0928-4931; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.164 |
Times cited |
34 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 4.164; 2010 IF: 2.180 |
Call Number |
UA @ lucian @ c:irua:122039 |
Serial |
242 |
Permanent link to this record |
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Author |
Neira, I.S.; Kolen'ko, Y.V.; Lebedev, O.I.; Van Tendeloo, G.; Gupta, H.S.; Matsushita, N.; Yoshimura, M.; Guitian, F. |
Title |
Rational synthesis of a nanocrystalline calcium phosphate cement exhibiting rapid conversion to hydroxyapatite |
Type |
A1 Journal article |
Year |
2009 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Materials science and engineering: part C: biomimetic materials |
Abbreviated Journal |
Mat Sci Eng C-Mater |
Volume |
29 |
Issue |
7 |
Pages |
2124-2132 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The rational synthesis, comprehensive characterization, and mechanical and micromechanical properties of a calcium phosphate cement are presented. Hydroxyapatite cement biomaterial was synthesized from reactive sub-micrometer-sized dicalcium phosphate dihydrate and tetracalcium phosphate via a dissolution-precipitation reaction using water as the liquid phase. As a result nanostructured, Ca-deficient and carbonated B-type hydroxyapatite is formed. The cement shows good processibility, sets in 22 ± 2 min and entirely transforms to the end product after 6 h of setting reaction, one of the highest conversion rates among previously reported for calcium phosphate cements based on dicalcium and tetracalcium phosphates. The combination of all elucidated physical-chemical traits leads to an essential bioactivity and biocompatibility of the cement, as revealed by in vitro acellular simulated body fluid and cell culture studies. The compressive strength of the produced cement biomaterial was established to be 25 ± 3 MPa. Furthermore, nanoindentation tests were performed directly on the cement to probe its local elasticity and plasticity at sub-micrometer/micrometer level. The measured elastic modulus and hardness were established to be Es = 23 ± 3.5 and H = 0.7 ± 0.2 GPa, respectively. These values are in close agreement with those reported in literature for trabecular and cortical bones, reflecting good elastic and plastic coherence between synthesized cement biomaterial and human bones. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lausanne |
Editor |
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Language |
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Wos |
000270159200008 |
Publication Date |
2009-04-20 |
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 |
0928-4931; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.164 |
Times cited |
18 |
Open Access |
|
Notes |
Esteem 026019 |
Approved |
Most recent IF: 4.164; 2009 IF: NA |
Call Number |
UA @ lucian @ c:irua:79312 |
Serial |
2812 |
Permanent link to this record |
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Author |
Voss, A.; Wei, H.Y.; Zhang, Y.; Turner, S.; Ceccone, G.; Reithmaier, J.P.; Stengl, M.; Popov, C. |
Title |
Strong attachment of circadian pacemaker neurons on modified ultrananocrystalline diamond surfaces |
Type |
A1 Journal article |
Year |
2016 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Materials science and engineering: part C: biomimetic materials |
Abbreviated Journal |
Mat Sci Eng C-Mater |
Volume |
64 |
Issue |
64 |
Pages |
278-285 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Diamond is a promising material for a number of bio-applications, including the fabrication of platforms for attachment and investigation of neurons and of neuroprostheses, such as retinal implants. In the current work ultrananocrystalline diamond (UNCD) films were deposited by microwave plasma chemical vapor deposition, modified by UV/O-3 treatment or NH3 plasma, and comprehensively characterized with respect to their bulk and surface properties, such as crystallinity, topography, composition and chemical bonding nature. The interactions of insect circadian pacemaker neurons with UNCD surfaces with H-, O- and NH2-terminations were investigated with respect to cell density and viability. The fast and strong attachment achieved without application of adhesion proteins allowed for advantageous modification of dispersion protocols for the preparation of primary cell cultures. Centrifugation steps, which are employed for pelletizing dispersed cells to separate them from dispersing enzymes, easily damage neurons. Now centrifugation can be avoided since dispersed neurons quickly and strongly attach to the UNCD surfaces. Enzyme solutions can be easily washed off without losing many of the dispersed cells. No adverse effects on the cell viability and physiological responses were observed as revealed by calcium imaging. Furthermore, the enhanced attachment of the neurons, especially on the modified UNCD surfaces, was especially advantageous for the immunocytochemical procedures with the cell cultures. The cell losses during washing steps were significantly reduced by one order of magnitude in comparison to controls. In addition, the integration of a titanium grid structure under the UNCD films allowed for individual assignment of physiologically characterized neurons to immunocytochemically stained cells. Thus, employing UNCD surfaces free of foreign proteins improves cell culture protocols and immunocytochemistry with cultured cells. The fast and strong attachment of neurons was attributed to a favorable combination of topography, surface chemistry and wettability. (C) 2016 Elsevier B.V. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lausanne |
Editor |
|
Language |
|
Wos |
000376547700033 |
Publication Date |
2016-03-26 |
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 |
0928-4931 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.164 |
Times cited |
7 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 4.164 |
Call Number |
UA @ lucian @ c:irua:134164 |
Serial |
4251 |
Permanent link to this record |
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|
|
Author |
Nowak, D.; Florek, M.; Nowak, J.; Kwiatek, W.; Lekki, J.; Chevallier, P.; Hacura, A.; Wrzalik, R.; Ben-Nissan, B.; Van Grieken, R.; Kuczumow, A. |
Title |
Morphology and the chemical make-up of the inorganic components of black corals |
Type |
A1 Journal article |
Year |
2009 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Materials science and engineering: part C: biomimetic materials |
Abbreviated Journal |
|
Volume |
29 |
Issue |
3 |
Pages |
1029-1038 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Black corals (Cnidaria, Antipatharia) from three different sources were investigated with the aim of detecting inorganic components and their morphology. In general, the skeleton of black corals was composed of the chitin fibrils admixed with peptides and the chitin presence was confirmed by the X-ray diffraction (XRD), Fourier Transformed Infrared Spectrometry (FTIR) and microRaman Microscopy, the latter giving the opportunity of tracing single fibrils and their location. The composition and concentrations of the inorganic components of the black corals were measured, using a scanning electron microprobe and micro-Particle Induced X-ray Emission (µ-PIXE). The application of such instruments enabled the estimation of the constituent distributions in a microscale. The mapping option was the most useful technique of making analyses in these studies, just to reveal the composition of chamber-like cells. Analysis of the morphology and microstructure showed that there were three distinct regions within the coral: a core and the cells encircled with adjacent interface gluing strips. The majority of the elements analyzed were selectively distributed and segregated in a striking way in mentioned distinctive zones of the skeleton and it was detected for the first time. The core area was characterized by the relatively elevated concentrations of Ca. The measurements gave extremely clear images of the distribution of particular elements in the skeletal tissue, with I, Ca, K and Fe much more concentrated in the gluing zones, while C, N, Na and Mg present in the interiors of particular skeletal cells. The distribution of some elements (Mg, Fe) and some compounds (chitin) and functional groups (SS, CI) allows differentiating the biological and mechanical functions of particular fragments of the rods. The kinds of elements and their concentrations measured were essentially in compliance with rare data available in the literature. The Raman technique gave the additional qualitative information about the structure of gluing zone and the chitin fibrils and surrounding matrix inside the cell interior. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000266520400065 |
Publication Date |
2008-09-10 |
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 |
|
ISSN |
0928-4931 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:76024 |
Serial |
8284 |
Permanent link to this record |
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Author |
Jain, R.; Rather, J.A.; Dwivedi, A. |
Title |
Voltammetric behaviour of nitroxazepine in solubilized system and biological fluids |
Type |
A1 Journal article |
Year |
2011 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Materials science and engineering: part C: biomimetic materials |
Abbreviated Journal |
|
Volume |
31 |
Issue |
2 |
Pages |
230-237 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
This study reports the development and validation of sensitive and selective assay method for the determination of the antidepressant drug in solubilized system and biological fluids. Solubilized system of different surfactants including cationic, anionic and non-ionic influences the electrochemical response of drug. Addition of cationic surfactant cetrimide to the solution containing drug enhances the peak current signal while anionic and non-ionic showed an opposite effect. The current signal due to reduction process was function of concentration of nitroxazepine, pH, type of surfactant and preconcentration time at the electrode surface. The reduction process is irreversible and adsorption controlled at HMDE. Various chemical and instrumental parameters affecting the monitored electroanalytical response were investigated and optimized for niroxazepine hydrochloride determination. The proposed SWCAdSV and DPCAdSV methods are linear over the concentration range 2.0 × 10-7 5.0 × 10-9 mol/L and 6.1 × 10-7 1.0 × 10-8 mol/L with detection limit of 1.62 × 10-10 mo/L and 1.4 × 10-9 mo/L respectively. The method shows good sensitivity, selectivity, accuracy and precision that makes it very suitable for determination of nitroxazepine in pharmaceutical formulation and biological fluids. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000286707900024 |
Publication Date |
2010-09-08 |
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 |
0928-4931 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:98685 |
Serial |
8743 |
Permanent link to this record |
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Author |
Vanhellemont, J.; Romano Rodriguez, A.; Fedina, L.; van Landuyt, J.; Aseev, A. |
Title |
Point defect reactions in silicon studied in situ by high flux electron irradiation in high voltage transmission electron microscope |
Type |
A1 Journal article |
Year |
1995 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Materials science and technology |
Abbreviated Journal |
Mater Sci Tech-Lond |
Volume |
11 |
Issue |
11 |
Pages |
1194-1202 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Results are presented of in situ studies of 1 MeV electron irradiation induced (113) defect generation in silicon containing different types and concentrations of extrinsic point defects. A semiquantitative model is developed describing the influence of interfaces and stress fields and of extrinsic point defects on the (113) defect generation in silicon during irradiation. The theoretical results obtained are correlated with experimental data obtained on silicon uniformly doped with boron and phosphorus and with observations obtained by irradiating cross-sectional samples of wafers with highly doped surface layers. It is shown that in situ irradiation in a high voltage election microscope is a powerful tool for studying local point defect reactions in silicon. (C) 1995 The Institute of Materials. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Inst Materials |
Place of Publication |
London |
Editor |
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Language |
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Wos |
A1995TQ95100016 |
Publication Date |
2014-01-09 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
ISSN |
0267-0836;1743-2847; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
0.995 |
Times cited |
7 |
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ lucian @ c:irua:95911 |
Serial |
2654 |
Permanent link to this record |
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Author |
Vanhellemont, J.; Romano-Rodriguez, A.; Fedina, L.; van Landuyt, J.; Aseev, A. |
Title |
Point defect reactions in silicon studies in situ by high flux electron irradiation in high voltage transmission electron microscope |
Type |
A3 Journal article |
Year |
1995 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Materials science and technology |
Abbreviated Journal |
|
Volume |
11 |
Issue |
|
Pages |
1194-1204 |
Keywords |
A3 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
A1995TQ95100016 |
Publication Date |
0000-00-00 |
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 |
|
ISSN |
|
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
7 |
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ lucian @ c:irua:13297 |
Serial |
2655 |
Permanent link to this record |
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Author |
Kuriplach, J.; van Petegem, S.; Hou, M.; Van Tendeloo, G.; Schryvers, D.; et al. |
Title |
Positron annihilation study of nanocrystalline Ni3Al : simulations and measurements |
Type |
A1 Journal article |
Year |
2001 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Materials science forum
T2 – 12th International Conference on Positron Annihilation (ICPA-12), AUG 06-12, 2000, UNIV BUNDERSWEHR MUNCHEN, NEUBIBERG, GERMANY |
Abbreviated Journal |
|
Volume |
363-3 |
Issue |
|
Pages |
94-96 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
A positron lifetime experiment is performed on samples produced by the compaction of nanocrystalline Ni3Al powder synthesized by the inert-gas condensation technique. In the lifetime spectrum we observe two components corresponding to defects. Computer (virtual) samples of n-Ni3Al are obtained using molecular dynamics combined with the Metropolis Monte Carlo technique. Positron lifetime calculations are then performed on selected regions of simulated samples. For this purpose, a new computational technique based on a generalization of the atomic superposition method for non-periodic systems was developed. Lifetimes calculated in this way are compared to experiment. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lausanne |
Editor |
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Language |
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Wos |
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Publication Date |
0000-00-00 |
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 |
0-87849-875-3 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:102865 |
Serial |
2681 |
Permanent link to this record |
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Author |
Schryvers, D.; Shi, H.; Martinez, G.T.; Van Aert, S.; Frenzel, J.; Van Humbeeck, J. |
Title |
Nano- and microcrystal investigations of precipitates, interfaces and strain fields in Ni-Ti-Nb by various TEM techniques |
Type |
P1 Proceeding |
Year |
2013 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Materials science forum
T2 – 9th European Symposium on Martensitic Transformations (ESOMAT 2012), SEP 09-16, 2012, St Petersburg, RUSSIA |
Abbreviated Journal |
|
Volume |
738/739 |
Issue |
|
Pages |
65-71 |
Keywords |
P1 Proceeding; Electron microscopy for materials research (EMAT) |
Abstract |
In the present contribution several advanced electron microscopy techniques are employed in order to describe chemical and structural features of the nano- and microstructure of a Ni45.5Ti45.5Nb9 alloy. A line-up of Nb-rich nano-precipitates is found in the Ni-Ti-rich austenite of as-cast material. Concentration changes of the matrix after annealing are correlated with changes in the transformation temperatures. The formation of rows and plates of larger Nb-rich precipitates and particles is described. The interaction of a twinned martensite plate with a Nb-rich nano-precipitate is discussed and the substitution of Nb atoms on the Ti-sublattice in the matrix is confirmed. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lausanne |
Editor |
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Language |
|
Wos |
000316089000011 |
Publication Date |
2013-03-11 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1662-9752; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
2 |
Open Access |
|
Notes |
Fwo |
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:104692 |
Serial |
2247 |
Permanent link to this record |
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|
|
Author |
Romano-Rodriguez, A.; Perez-Rodriguez, A.; Serre, C.; van Landuyt, J.; et al. |
Title |
Epitaxial growth of \beta-SiC on ion-beam synthesized \beta-SiC : structural characterization |
Type |
A1 Journal article |
Year |
2000 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Materials science forum
T2 – International Conference on Silicon Carbide and Related Materials, OCT 10-15, 1999, RES TRIANGLE PK, NORTH CAROLINA |
Abbreviated Journal |
Mater Sci Forum |
Volume |
338-3 |
Issue |
|
Pages |
309-312 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
In this work we present for the first time, to our knowledge, the CVD epitaxial growth of beta -SiC using an ion beam synthesized (IBS) beta -SiC layer as seed, which has been formed by multiple implantation into Si wafers at 500 degreesC. The ion beam synthesized continuous layer is constituted by beta -SiC nanocrystals that are well oriented relative to the silicon substrate. Comparison of the epitaxial growth on these samples with that on silicon test samples, both on and off-axis, is performed. The results show that the epitaxial growth can be achieved on the IBS samples without the need of the carbonization step and that the structural quality of the CVD layer is comparable to that obtained on a carbonized silicon sample. Improvement of the quality of the deposited layer is proposed. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
Trans tech publications ltd |
Place of Publication |
Zurich-uetikon |
Editor |
|
Language |
|
Wos |
000165996700075 |
Publication Date |
0000-00-00 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0255-5476 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
2 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:104262 |
Serial |
1071 |
Permanent link to this record |
|
|
|
Author |
Cao, S.; Tirry, W.; van den Broek, W.; Schryvers, D. |
Title |
3D reconstruction of Ni4Ti3 precipitates in a Ni51Ti49 alloy in a FIB/SEM dual-beam system |
Type |
A1 Journal article |
Year |
2008 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Materials science forum |
Abbreviated Journal |
|
Volume |
583 |
Issue |
|
Pages |
277-284 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
Abstract |
Ni4Ti3 precipitates play an important role in the shape memory and superelastic behaviour of thermo-mechanically treated Ni-Ti material. The 3D morphology and distribution of such precipitates with lenticular shape and rhombohedral atomic structure in the austenitic B2 matrix of a binary Ni-rich Ni-Ti alloy has been elucidated via a slice view procedure in a Dual-Beam FIB/SEM system. With the sequence of cross-section SE images obtained from the SEM, a 3D reconstruction has been achieved after proper alignment and image processing, from which both qualitative and quantitative analysis can be performed. Careful imaging is needed to ensure that all variants of the precipitates are observed with equal probability, regardless sample orientation. Moreover, due to the weak contrast of the precipitates, proper imaging conditions need to be selected to allow for semi-automated image treatment. Finally, a volume ratio of 10.2% for the Ni4Ti3 precipitates could be calculated, summed over all variants, which yields a net composition of Ni50.36Ti49.64 for the matrix, leading to an increase of 113 degrees for the martensitic start temperature Ms. Also, the expected relative orientation of the different variants of the precipitates could be confirmed. In the near future, other quantitative measures on the distribution of the precipitates can be expected. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lausanne |
Editor |
|
Language |
|
Wos |
|
Publication Date |
2009-03-11 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1662-9752; |
ISBN |
|
Additional Links |
UA library record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
Multimat; Fwo |
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:77454 |
Serial |
16 |
Permanent link to this record |
|
|
|
Author |
van Landuyt, J.; Van Tendeloo, G.; Amelinckx, S.; Zhang, X.F.; Zhang, X.B.; Luyten, W. |
Title |
Crystallography of fullerites and related graphene textures |
Type |
A1 Journal article |
Year |
1994 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Materials science forum |
Abbreviated Journal |
|
Volume |
150/151 |
Issue |
|
Pages |
53-64 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lausanne |
Editor |
|
Language |
|
Wos |
A1994BC12F00004 |
Publication Date |
0000-00-00 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0255-5476; 1662-9752 |
ISBN |
|
Additional Links |
UA library record; WoS full record; |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ lucian @ c:irua:10001 |
Serial |
590 |
Permanent link to this record |
|
|
|
Author |
Wang, X.; Amin-Ahmadi, B.; Schryvers, D.; Verlinden, B.; Van Humbeeck, J. |
Title |
Effect of annealing on the transformation behavior and mechanical properties of two nanostructured Ti-50.8at.%Ni thin wires produced by different methods |
Type |
A1 Journal article |
Year |
2013 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Materials science forum |
Abbreviated Journal |
|
Volume |
738/739 |
Issue |
|
Pages |
306-310 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
A Ti-50.8at.%Ni wire produced using a co-drawing method and a commercial Ti-50.8at.%Ni wire were annealed at different temperatures between 450°C and 700°C. Grains with diameter less than 100nm were revealed by transmission electron microscopy for both wires before annealing treatment. However, the microstructural heterogeneity of the co-drawn wire is more obvious than that of the commercial wire. Multi-stage martensitic transformation was observed in the co-drawn wire, compared with the one-stage A↔M transformation in the commercial wire after annealing at 600°C for 30min. The differences of total elongation, plateau strain and pseudoelastic recoverable strain between the commercial wire and the co-drawn wire were also observed. The differences of the transformation behavior and mechanical properties between the commercial wire and the co-drawn wire are attributed to the microstructural difference between these two wires. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lausanne |
Editor |
|
Language |
|
Wos |
000316089000055 |
Publication Date |
2013-03-11 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1662-9752; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
5 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:104691 |
Serial |
798 |
Permanent link to this record |
|
|
|
Author |
Shi, H.; Frenzel, J.; Schryvers, D. |
Title |
EM characterization of precipitates in as-cast and annealed Ni45.5Ti45.5Nb9 shape memory alloys |
Type |
P1 Proceeding |
Year |
2013 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Materials science forum |
Abbreviated Journal |
|
Volume |
738/739 |
Issue |
|
Pages |
113-117 |
Keywords |
P1 Proceeding; Electron microscopy for materials research (EMAT) |
Abstract |
Nb-rich precipitates in the matrix of as-cast and annealed Ni45.5Ti45.5Nb9 alloys are investigated by scanning and scanning transmission electron microscopy, including slice-and-view and geometric phase analysis (GPA). The Nb-rich bcc nano-precipitates in the as-cast alloy have a 10% lattice parameter difference with the B2 matrix and reveal compensating interface dislocations. The 3D reconstruction of the configuration of small Nb-rich precipitates in the annealed alloy reveals a wall-like distribution of precipitates, which may increase the thermal hysteresis of the material. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lausanne |
Editor |
|
Language |
|
Wos |
000316089000020 |
Publication Date |
2013-03-11 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1662-9752; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
1 |
Open Access |
|
Notes |
Fwo |
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:104690 |
Serial |
1028 |
Permanent link to this record |
|
|
|
Author |
Teodorescu, V.S.; Nistor, L.C.; van Landuyt, J. |
Title |
High resolution TEM observation of in situ colloid formation in CaF2 crystals |
Type |
A1 Journal article |
Year |
1997 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Materials science forum |
Abbreviated Journal |
|
Volume |
239-241 |
Issue |
|
Pages |
671-674 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lausanne |
Editor |
|
Language |
|
Wos |
A1997BH33W00145 |
Publication Date |
0000-00-00 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0255-5476; 1662-9752 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
3 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:21404 |
Serial |
1460 |
Permanent link to this record |
|
|
|
Author |
Veljkovic, D.; Tadić, M.; Peeters, F.M. |
Title |
Intersublevel absorption in stacked n-type doped self-assembled quantum dots |
Type |
A1 Journal article |
Year |
2005 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Materials science forum |
Abbreviated Journal |
Mater Sci Forum |
Volume |
494 |
Issue |
|
Pages |
37-42 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The intersublevel absorption in n-doped InAs/GaAs self-assembled quantum-dot molecules composed of three quantum dots is theoretically considered. The transition matrix elements and the transition energies are found to vary considerably with the spacer thickness. For s polarized light, decreasing the thickness of the spacer between the dots brings about crossings between the transition matrix elements, but the overall absorption is not affected by the variation of the spacer thickness. For p-polarized light and thick spacers, there are no available transitions in the single quantum dot, but a few of them emerge as a result of the electron state splitting in the stacks of coupled quantum dots, which leads to a considerable increase of the transition matrix elements, exceeding by an order of magnitude values of the matrix elements for s-polarized light. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lausanne |
Editor |
|
Language |
|
Wos |
|
Publication Date |
0000-00-00 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0255-5476; 1662-9752 |
ISBN |
|
Additional Links |
UA library record; WoS full record; |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:94746 |
Serial |
1715 |
Permanent link to this record |
|
|
|
Author |
Partoens, B.; Matulis, A.; Peeters, F.M. |
Title |
Magnetoplasma excitations in vertically coupled quantum dot systems |
Type |
A1 Journal article |
Year |
1999 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Materials science forum |
Abbreviated Journal |
Mater Sci Forum |
Volume |
297/298 |
Issue |
|
Pages |
225-228 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lausanne |
Editor |
|
Language |
|
Wos |
000080081600043 |
Publication Date |
0000-00-00 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0255-5476; 1662-9752 |
ISBN |
|
Additional Links |
UA library record; WoS full record; |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:24176 |
Serial |
1920 |
Permanent link to this record |
|
|
|
Author |
Krsmanovic, R.; Bertoni, G.; Van Tendeloo, G. |
Title |
Structural characterization of erbium doped LAS glass ceramics obtained by glass melting technique |
Type |
A1 Journal article |
Year |
2007 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Materials science forum |
Abbreviated Journal |
|
Volume |
555 |
Issue |
|
Pages |
377-381 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Samples of transparent glass-ceramics in the ternary system Li2O-Al2O3-SiO2 (LAS), with Er2O3 as a luminescent dopant, are investigated. The initial glass is obtained by the classical melting technique. In order to induce ceramization of the glass, TiO2 and ZrO2 are added in small amount as nucleating agents. The thermal treatments at 730 and 770 degrees C are carried out to promote formation of titanium zirconate solid solution precipitates. The spatial distribution of the precipitates in the material, their morphology, and their composition are investigated with TEM, HRTEM, HAADF-STEM, EELS and EFTEM. The results demonstrate that with the glass-melting preparation technique it is possible to achieve small nanoparticles with uniform distribution and higher number density than with the sol-gel glass preparation. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lausanne |
Editor |
|
Language |
|
Wos |
|
Publication Date |
0000-00-00 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0255-5476 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:94673 |
Serial |
3220 |
Permanent link to this record |
|
|
|
Author |
Nistor, L.C.; van Landuyt, J.; Ralchenko, V.G.; Obratzova, E.D.; Korothushenko, K.G.; Smolin, A.A. |
Title |
Structural studies of nanocrystalline diamond thin films |
Type |
A1 Journal article |
Year |
1997 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Materials science forum |
Abbreviated Journal |
|
Volume |
239-241 |
Issue |
|
Pages |
115-118 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lausanne |
Editor |
|
Language |
|
Wos |
A1997BH33W00026 |
Publication Date |
0000-00-00 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0255-5476; 1662-9752 |
ISBN |
|
Additional Links |
UA library record; WoS full record; |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:21403 |
Serial |
3260 |
Permanent link to this record |
|
|
|
Author |
Hens, S.; van Landuyt, J.; Bender, H.; Boullart, W.; Vanhaelemeersch, S. |
Title |
Chemical and structural analysis of etching residue layers in semiconductor devices with energy filtering transmission electron microscopy |
Type |
A1 Journal article |
Year |
2001 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Materials science in semiconductor processing |
Abbreviated Journal |
Mat Sci Semicon Proc |
Volume |
4 |
Issue |
1/3 |
Pages |
109-111 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The use of an energy-filtering held emission gun transmission electron microscope (CM30 FEG Ultratwin) allows, apart from imaging morphologies down to nanometer scale, the fast acquisition of high-resolution element distributions. Electrons that have lost energy corresponding to characteristic inner-shell loss edges are used to form the element maps. The production of Ultra Large-Scale Integration (ULSI) devices with dimensions below 0.25 mum requires among others the formation of a multilayer metallization scheme by means of repeatedly applying the deposition and etching of dielectrics and metals. In this work the evolution of the surface chemical species on etched Al lines in a post-etch cleaning process has been investigated by energy filtering transmission electron microscopy, with the aim to understand the role of each process step on the removal of the etching residues. (C) 2001 Elsevier Science Ltd. All rights reserved. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
Language |
|
Wos |
000167727200026 |
Publication Date |
2002-10-14 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1369-8001; |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
2.359 |
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.359; 2001 IF: 0.419 |
Call Number |
UA @ lucian @ c:irua:94967 |
Serial |
343 |
Permanent link to this record |
|
|
|
Author |
Stuer, C.; van Landuyt, J.; Bender, H.; Rooyackers, R.; Badenes, G. |
Title |
The use of convergent beam electron diffraction for stress measurements in shallow trench isolation structures |
Type |
A1 Journal article |
Year |
2001 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Materials science in semiconductor processing |
Abbreviated Journal |
Mat Sci Semicon Proc |
Volume |
4 |
Issue |
1/3 |
Pages |
117-119 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Shallow trench isolation (STI) is a promising technology for the isolation structures of the new generation of ULSI devices with dimensions below 0.18 mum. The various processing steps cause stress fields in STI structures, which can lead to defect formation in the silicon substrate. In their turn, stress fields affect the electrical parameters and the reliability of devices. Convergent beam electron diffraction (CBED) is used in this study to examine the influence of a wet and a dry pre-gate oxidation on the stress distribution around STI structures. The measurements are performed on STI structures with different width and spacing. CBED analysis is compared with bright-field TEM images. Defects are observed in high-strain areas of small isolated structures. (C) 2001 Elsevier Science Ltd. All rights reserved. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
Language |
|
Wos |
000167727200028 |
Publication Date |
2002-10-14 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1369-8001; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.359 |
Times cited |
6 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.359; 2001 IF: 0.419 |
Call Number |
UA @ lucian @ c:irua:94968 |
Serial |
3602 |
Permanent link to this record |
|
|
|
Author |
Gkanatsiou, A.; Lioutas, C.B.; Frangis, N.; Polychroniadis, E.K.; Prystawko, P.; Leszczynski, M.; Altantzis, T.; Van Tendeloo, G. |
Title |
Influence of 4H-SiC substrate miscut on the epitaxy and microstructure of AlGaN/GaN heterostructures |
Type |
A1 Journal article |
Year |
2019 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Materials science in semiconductor processing |
Abbreviated Journal |
Mat Sci Semicon Proc |
Volume |
91 |
Issue |
|
Pages |
159-166 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
AlGaN/GaN heterostructures were grown on “on-axis” and 2° off (0001) 4H-SiC substrates by metalorganic vapor phase epitaxy (MOVPE). Structural characterization was performed by transmission electron microscopy. The dislocation density, being greater in the on-axis case, is gradually reduced in the GaN layer and is forming
dislocation loops in the lower region. Steps aligned along [11̅00] in the off-axis case give rise to simultaneous defect formation. In the on-axis case, an almost zero density of steps is observed, with the main origin of defects probably being the orientation mismatch at the grain boundaries between the small not fully coalesced AlN grains. V-shaped formations are observed in the AlN nucleation layer, but are more frequent in the off-axis case, probably enhanced by the presence of steps. These V-shaped formations are completely overgrown by the GaN layer, during the subsequent deposition, presenting AlGaN areas in the walls of the defect, indicating an interdiffusion between the layers. Finally, at the AlGaN/GaN heterostructure surface in the on-axis case, V-shapes are observed, with the AlN spacer and AlGaN (21% Al) thickness on relaxed GaN exceeding the critical thickness for relaxation. On the other hand, no relaxation in the form of V-shape creation is observed in the off-axis case, probably due to the smaller AlGaN thickness (less than 21% Al). The AlN spacer layer, grown in between the heterostructure, presents a uniform thickness and clear interfaces. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000454537700022 |
Publication Date |
2018-11-26 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1369-8001 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.359 |
Times cited |
1 |
Open Access |
Not_Open_Access |
Notes |
Funding: This work was supported by the IKY Fellowships of Excellence for Postgraduate Studies in Greece-SIEMENS Program; the Greek General Secretariat for Research and Technology, contract SAE 013/8–2009SE 01380012; and the JU ENIAC Project LAST POWER Large Area silicon carbide Substrates and heteroepitaxial GaN for POWER device applications [grant number 120218]. Also part of the research leading to these results has received funding from the European Union Seventh Framework Program under Grant Agreement 312483 – ESTEEM2 (Integrated Infrastructure Initiative–I3). T.A. acknowledges financial support from the Research Foundation Flanders (FWO, Belgium) through a post-doctoral grant. |
Approved |
Most recent IF: 2.359 |
Call Number |
EMAT @ emat @UA @ admin @ c:irua:156200 |
Serial |
5149 |
Permanent link to this record |
|
|
|
Author |
Hoat, D.M.; Nguyen, D.K.; Bafekry, A.; Van On, V.; Ul Haq, B.; Rivas-Silva, J.F.; Cocoletzi, G.H. |
Title |
Strain-driven modulation of the electronic, optical and thermoelectric properties of beta-antimonene monolayer : a hybrid functional study |
Type |
A1 Journal article |
Year |
2021 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Materials Science In Semiconductor Processing |
Abbreviated Journal |
Mat Sci Semicon Proc |
Volume |
131 |
Issue |
|
Pages |
105878 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Electronic, optical, and thermoelectric properties of the beta-antimonene (beta-Sb) monolayer under the external biaxial strain effects are fully investigated through the first-principles calculations. The studied two-dimensional (2D) system is dynamically and structurally stable as examined via phonon spectrum and cohesive energy. At equilibrium, the beta-Sb single layer exhibits an indirect band gap of 1.310 and 1.786 eV as predicted by the PBE and HSE06 functionals, respectively. Applying external strain may induce the indirect-direct gap transition and significant variation of the energy gap. The calculated optical spectra indicate the enhancement of the optical absorption in a wide energy range from infrared to ultraviolet as induced by the applied strain. In the visible and ultraviolet regime, the absorption coefficient can reach values as large as 82.700 (10(4)/cm) and 91.458 (10(4)/cm). Results suggest that the thermoelectric performance may be improved considerably by applying proper external strain with the figure of merit reaching a value of 0.665. Our work demonstrates that the external biaxial strains may be an effective method to make the beta-Sb monolayer prospective 2D material for optoelectronic and thermoelectric applications. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000663422800002 |
Publication Date |
2021-04-23 |
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 |
1369-8001 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.359 |
Times cited |
|
Open Access |
Not_Open_Access |
Notes |
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Approved |
Most recent IF: 2.359 |
Call Number |
UA @ admin @ c:irua:179565 |
Serial |
7021 |
Permanent link to this record |
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Author |
Yorulmaz, B.; Ozden, A.; Sar, H.; Ay, F.; Sevik, C.; Perkgoz, N.K. |
Title |
CVD growth of monolayer WS2 through controlled seed formation and vapor density |
Type |
A1 Journal article |
Year |
2019 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Materials science in semiconductor processing |
Abbreviated Journal |
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Volume |
93 |
Issue |
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Pages |
158-163 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Large area, single layer WS2 has a high potential for use in optoelectrical devices with its high photo-luminescence intensity and low response time. In this work, we demonstrate a systematic study of controlled tungsten disulfide (WS2) monolayer growth using chemical vapor deposition (CVD) technique. With a detailed investigation of process parameters such as H-2 gas inclusion into the main carrier gas, growth temperature and duration, we have gained insight into two-dimensional (2D) WS2 synthesis through controlling the seed formations and the radical vapor density associated with WO3. We confirm that H-2 gas, when included to the carrier gas, is directly involved in WO3 reduction due to its reductive reagent nature, which provides a more effective sulfurization and monolayer formation process. Additionally, by changing the CVD growth configuration, hence, increasing the tungsten related vapor density and confining the reactant radicals, we succeed in realizing larger WS(2 )monolayers, which is still a technological challenge in order to utilize these structures for practical applications. Further optimization of the growth procedure is demonstrated by tuning the growth duration to prevent the excess seed formations and additional layers which will possibly limit the device performance of the monolayer flakes or films when applied. |
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Place of Publication |
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Language |
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Wos |
000457727300018 |
Publication Date |
2019-01-09 |
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 |
1369-8001 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:193782 |
Serial |
7748 |
Permanent link to this record |
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Author |
Akamine, H.; Mitsuhara, M.; Nishida, M.; Samaee, V.; Schryvers, D.; Tsukamoto, G.; Kunieda, T.; Fujii, H. |
Title |
Precipitation behaviors in Ti-2.3 Wt Pct Cu alloy during isothermal and two-step aging |
Type |
A1 Journal article |
Year |
2021 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Metallurgical And Materials Transactions A-Physical Metallurgy And Materials Science |
Abbreviated Journal |
Metall Mater Trans A |
Volume |
52 |
Issue |
|
Pages |
2760-2772 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Time evolution of precipitates related to age-hardening in Ti-2.3 wt pct Cu alloys was investigated by electron microscopy. In isothermal aging at 723 K, the hardness increases continuously owing to precipitation strengthening, whereas in two-step aging where the aging temperature is switched from 673 K to 873 K after 100 hours, the hardness is found to drastically drop after the aging temperature switches. In isothermal aging, metastable and stable precipitates are independently nucleated, whereas characteristic V-shaped clusters of precipitates are observed during the two-step aging. It is revealed by atomic-scale observations that the V-shaped clusters are composed of metastable and stable precipitates and each type of precipitate has a different orientation relationship with the alpha phase: (10 (3) over bar)//(0001)(alpha) and [0 (1) over bar0]//respectively. The drop in hardness during two-step aging can be explained by a synergistic effect of decreased precipitation strengthening and solid solution strengthening. (C) The Minerals, Metals & Materials Society and ASM International 2021 |
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Place of Publication |
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Language |
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Wos |
000644823000001 |
Publication Date |
2021-04-27 |
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 |
1073-5623 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
1.874 |
Times cited |
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Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 1.874 |
Call Number |
UA @ admin @ c:irua:178222 |
Serial |
6786 |
Permanent link to this record |
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Author |
Pittarello, L.; Ji, G.; Yamaguchi, A.; Schryvers, D.; Debaille, V.; Claeys, P. |
Title |
From olivine to ringwoodite : a TEM study of a complex process |
Type |
A1 Journal article |
Year |
2015 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Meteoritics and Planetary Science |
Abbreviated Journal |
Meteorit Planet Sci |
Volume |
50 |
Issue |
50 |
Pages |
944-957 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The study of shock metamorphism of olivine might help to constrain impact events in the history of meteorites. Although shock features in olivine are well known, so far, there are processes that are not yet completely understood. In shock veins, olivine clasts with a complex structure, with a ringwoodite rim and a dense network of lamellae of unidentified nature in the core, have been reported in the literature. A highly shocked (S5-6), L6 meteorite, Asuka 09584, which was recently collected in Antarctica by a Belgian-Japanese joint expedition, contains this type of shocked olivine clasts and has been, therefore, selected for detailed investigations of these features by transmission electron microscopy (TEM). Petrographic, geochemical, and crystallographic studies showed that the rim of these shocked clasts consists of an aggregate of nanocrystals of ringwoodite, with lower Mg/Fe ratio than the unshocked olivine. The clast's core consists of an aggregate of iso-oriented grains of olivine and wadsleyite, with higher Mg/Fe ratio than the unshocked olivine. This aggregate is crosscut by veinlets of nanocrystals of olivine, with extremely low Mg/Fe ratio. The formation of the ringwoodite rim is likely due to solid-state, diffusion-controlled, transformation from olivine under high-temperature conditions. The aggregate of iso-oriented olivine and wadsleyite crystals is interpreted to have formed also by a solid-state process, likely by coherent intracrystalline nucleation. Following the compression, shock release is believed to have caused opening of cracks and fractures in olivine and formation of olivine melt, which has lately crystallized under postshock equilibrium pressure conditions as olivine. |
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Publisher |
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Place of Publication |
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Language |
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Wos |
000354258400008 |
Publication Date |
2015-04-20 |
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 |
1086-9379; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.391 |
Times cited |
8 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.391; 2015 IF: 3.104 |
Call Number |
c:irua:126058 |
Serial |
1283 |
Permanent link to this record |
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Author |
Annegarn, H.J.; Storms, H.; Van Grieken, R.E.; Booth-Jones, P.A. |
Title |
Composition and size of individual particles from a gold mine atmosphere |
Type |
A3 Journal article |
Year |
1987 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Mining science & technology |
Abbreviated Journal |
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Volume |
5 |
Issue |
2 |
Pages |
111-119 |
Keywords |
A3 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Airborne dust particles were collected in a return airway of a South African gold mine using a 7-stage, single-orifice cascade impactor. Between 70 and 130 individual particles were analysed on each stage using automated electron-probe x-ray microanalysis (EPXMA). Particle size and shape parameters are given for different classes of particles sorted by elemental composition. Silicon-rich particles are the most abundant overall, while chlorine-rich particles dominate (up to 80%) in the range 0.21.0 μm. It is shown that EPXMA characterisation of particles can be used to infer relative contributions of various particle sources and dust generating processes to the total dust concentrations in mine atmospheres. An understanding of the nature and source of particles is essential for any source control strategy. We conclude that the EPXMA technique merits inclusion in the repertoire of techniques used for characterising underground dust. |
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Publication Date |
2004-12-15 |
Series Editor |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0167-9031 |
ISBN |
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Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:116777 |
Serial |
7701 |
Permanent link to this record |
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Author |
Orlinskii, S.B.; Bogomolov, R.S.; Kiyamova, A.M.; Yavkin, B.V.; Mamin, G.M.; Turner, S.; Van Tendeloo, G.; Shiryaev, A.A.; Vlasov, I.I.; Shenderova, O. |
Title |
Identification of substitutional nitrogen and surface paramagnetic centers in nanodiamond of dynamic synthesis by electron paramagnetic resonance |
Type |
A1 Journal article |
Year |
2011 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Nanoscience and nanotechnology letters |
Abbreviated Journal |
Nanosci Nanotech Let |
Volume |
3 |
Issue |
1 |
Pages |
63-67 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Production of nanodiamond particles containing substitutional nitrogen is important for a wide variety of advanced applications. In the current work nanodiamond particles synthesized from a mixture of graphite and hexogen were analyzed to determine the presence of substitutional nitrogen using pulsed electron paramagnetic resonance (EPR) spectroscopy. Nitrogen paramagnetic centers in the amount of 1.2 ppm have been identified. The spin relaxation characteristics for both nitrogen and surface defects are also reported. A new approach for efficient depletion of the strong non-nitrogen EPR signal in nanodiamond material by immersing nanodiamond particles into ice matrix is suggested. This approach allows an essential decrease of the spin relaxation time of the dominant non-nitrogen defects, while preserving the substitutional nitrogen spin relaxation time. |
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Wos |
000293211200012 |
Publication Date |
2011-09-19 |
Series Editor |
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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 |
1941-4900;1941-4919; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.889 |
Times cited |
14 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.889; 2011 IF: 0.528 |
Call Number |
UA @ lucian @ c:irua:91943 |
Serial |
1548 |
Permanent link to this record |