| Records |
| Author |
Burriel, M.; Casa-Cabanas, M.; Zapata, J.; Tan, H.; Verbeeck, J.; Solis, C.; Roqueta, J.; Skinner, S.J.; Kilner, J.A.; Van Tendeloo, G.; Santiso, J. |
| Title |
Influence of the microstructure on the high-temperature transport properties of GdBaCo2O5.5+\delta epitaxial films |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
| Volume |
22 |
Issue |
19 |
Pages |
5512-5520 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Epitaxial thin films of GdBaCo2O5.5+δ (GBCO) grown by pulsed laser deposition have been studied as a function of deposition conditions. The variation in film structure, domain orientation, and microstructure upon deviations in the cation composition have been correlated with the charge transport properties of the films. The epitaxial GBCO films mainly consist of single- and double-perovskite regions that are oriented in different directions depending on the deposition temperature. Additionally, cobalt depletion induces the formation of a high density of stacking defects in the films, consisting of supplementary GdO planes along the c-axis of the material. The presence of such defects progressively reduces the electrical conductivity. The films closer to the stoichiometric composition have shown p-type electronic conductivity at high pO2 with values as high as 800 S/cm at 330 °C in 1 atm O2, and with a pO2 power dependence with an exponent as low as 1/25, consistent with the behavior reported for bulk GBCO. These values place GBCO thin films as a very promising material to be applied as cathodes in intermediate temperature solid oxide fuel cells. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| Language |
|
Wos |
000282471000013 |
Publication Date  |
2010-09-20 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
9.466 |
Times cited |
17 |
Open Access |
|
| Notes |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 9.466; 2010 IF: 6.400 |
| Call Number |
UA @ lucian @ c:irua:85412UA @ admin @ c:irua:85412 |
Serial |
1648 |
| Permanent link to this record |
| |
|
| |
| Author |
Tian, H.; Schryvers, D.; Liu, D.; Jiang, Q.; van Humbeeck, J. |
| Title |
Stability of Ni in nitinol oxide surfaces |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Acta biomaterialia |
Abbreviated Journal |
Acta Biomater |
| Volume |
7 |
Issue |
2 |
Pages |
892-899 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The stability of Ni in titanium oxide surface layers on nitinol wires known to release certain amounts of Ni was investigated by first principles density functional theory and transmission electron microscopy. The oxides were identified as a combination of TiO and TiO2 depending on the thickness of the layer. The calculations indicate that free Ni atoms can exist in TiO at ambient temperature while Ni particles form in TiO2, which was confirmed by the transmission electron microscopy observations. The results are discussed with respect to surface stability and Ni release due to free Ni atoms and Ni particles. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
S.l. |
Editor |
|
| Language |
|
Wos |
000286707700047 |
Publication Date |
2010-09-17 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1742-7061; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
6.319 |
Times cited |
39 |
Open Access |
|
| Notes |
Fwo |
Approved |
Most recent IF: 6.319; 2011 IF: 4.865 |
| Call Number |
UA @ lucian @ c:irua:85998 |
Serial |
3128 |
| Permanent link to this record |
| |
|
| |
| Author |
Schapotschnikow, P.; van Huis, M.A.; Zandbergen, H.W.; Vanmaekelbergh, D.; Vlugt, T.J.H. |
| Title |
Morphological transformations and fusion of PbSe nanocrystals studied using atomistic simulations |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Nano letters |
Abbreviated Journal |
Nano Lett |
| Volume |
10 |
Issue |
10 |
Pages |
3966-3971 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Molecular dynamics simulations are performed on capped and uncapped PbSe nanocrystals, employing newly developed classical interaction potentials. Here, we show that two uncapped nanocrystals fuse efficiently via direct surface attachment, even if they are initially misaligned. In sharp contrast to the general belief, interparticle dipole interactions do not play a significant role in this oriented attachment process. Furthermore, it is shown that presumably polar, capped PbSe{111} facets are never fully Pb- or Se-terminated. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Washington |
Editor |
|
| Language |
|
Wos |
000282727600028 |
Publication Date |
2010-09-16 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1530-6984;1530-6992; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
12.712 |
Times cited |
59 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 12.712; 2010 IF: 12.219 |
| Call Number |
UA @ lucian @ c:irua:84902 |
Serial |
2205 |
| Permanent link to this record |
| |
|
| |
| Author |
Verbeeck, J.; Tian, H.; Schattschneider, P. |
| Title |
Production and application of electron vortex beams |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Nature |
Abbreviated Journal |
Nature |
| Volume |
467 |
Issue |
7313 |
Pages |
301-304 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Vortex beams (also known as beams with a phase singularity) consist of spiralling wavefronts that give rise to angular momentum around the propagation direction. Vortex photon beams are widely used in applications such as optical tweezers to manipulate micrometre-sized particles and in micro-motors to provide angular momentum1, 2, improving channel capacity in optical3 and radio-wave4 information transfer, astrophysics5 and so on6. Very recently, an experimental realization of vortex beams formed of electrons was demonstrated7. Here we describe the creation of vortex electron beams, making use of a versatile holographic reconstruction technique in a transmission electron microscope. This technique is a reproducible method of creating vortex electron beams in a conventional electron microscope. We demonstrate how they may be used in electron energy-loss spectroscopy to detect the magnetic state of materials and describe their properties. Our results show that electron vortex beams hold promise for new applications, in particular for analysing and manipulating nanomaterials, and can be easily produced. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000281824900033 |
Publication Date |
2010-09-14 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0028-0836;1476-4687; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
40.137 |
Times cited |
626 |
Open Access |
|
| Notes |
Esteem 026019; Fwo |
Approved |
Most recent IF: 40.137; 2010 IF: 36.104 |
| Call Number |
UA @ lucian @ c:irua:84878UA @ admin @ c:irua:84878 |
Serial |
2720 |
| Permanent link to this record |
| |
|
| |
| Author |
Yang, T.; Perkisas, T.; Hadermann, J.; Croft, M.; Ignatov, A.; Greenblatt, M. |
| Title |
B-site ordered perovskite LaSrMnNbO6 : synthesis, structure and antiferromagnetism |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
| Volume |
183 |
Issue |
11 |
Pages |
2689-2694 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
LaSrMnNbO6 has been synthesized by high temperature solid state reaction under 1% H2/Ar dynamic flow. The structure is determined by Rietveld refinement of the powder X-ray diffraction data. It crystallizes in the monoclinic space group P21/n with the unit cell parameters: a=5.69187(12), b=5.74732(10), c=8.07018(15) Å and β=90.0504(29)°, which were also confirmed by electron diffraction. The Mn2+ and Nb5+ ions, whose valence states are confirmed by X-ray absorption near-edge spectroscopy, are almost completely ordered over the B-site (<1% inversion) of the perovskite structure due to the large differences of both cationic size (0.19 Å) and charge. The octahedral framework displays significant tilting distortion according to Glazers tilt system a−b−c+. Upon heating, LaSrMnNbO6 decomposes at 690 °C under O2 flow or at 775 °C in air. The magnetic susceptibility data indicate the presence of long-range antiferromagnetic ordering at TN=8 K; the experimentally observed effective paramagnetic moment, μeff=5.76 μB for high spin Mn2+ (3d5, S=5/2) is in good agreement with the calculated value (μcalcd=5.92 μB). |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000284179800028 |
Publication Date |
2010-09-13 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0022-4596; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.299 |
Times cited |
13 |
Open Access |
|
| Notes |
Esteem 026019 |
Approved |
Most recent IF: 2.299; 2010 IF: 2.261 |
| Call Number |
UA @ lucian @ c:irua:85805 |
Serial |
212 |
| Permanent link to this record |
| |
|
| |
| Author |
van den Heuvel, W.; Tikhomirov, V.K.; Kirilenko, D.; Schildermans, N.; Chibotaru, L.F.; Vanacken, J.; Gredin, P.; Mortier, M.; Van Tendeloo, G.; Moshchalkov, V.V. |
| Title |
Ultralow blocking temperature and breakdown of the giant spin model in Er3+-doped nanoparticles |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
82 |
Issue |
9 |
Pages |
094421-094421,8 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The magnetization of luminescent Er3+-doped PbF2 nanoparticles (formula Er0.3Pb0.7F2.3) has been studied. Despite the high concentration of the doping Er3+ ions and relatively large size (8 nm) of these nanoparticles we have found no deviation between field-cooled and zero-field-cooled magnetization curves down to T=0.35 K, which points out an ultralow blocking temperature for the reversal of magnetization. We also have found strongly deviating magnetization curves M(H/T) for different temperatures T. These results altogether show that the investigated nanoparticles are not superparamagnetic, but rather each Er3+ ion in these nanoparticles is found in a paramagnetic state down to very low temperatures, which implies the breakdown of the Néel-Brown giant spin model in the case of these nanoparticles. Calculations of magnetization within a paramagnetic model of noninteracting Er3+ ions completely support this conclusion. Due to the ultralow blocking temperature, these nanoparticles have a potential for magnetic field-induced nanoscale refrigeration with an option of their optical localization and temperature control. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000281773300005 |
Publication Date |
2010-09-13 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
11 |
Open Access |
|
| Notes |
Fwo |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
| Call Number |
UA @ lucian @ c:irua:85423 |
Serial |
3796 |
| Permanent link to this record |
| |
|
| |
| Author |
Tikhomirov, A.S.; Sorokina, N.E.; Shornikova, O.N.; Morozov, V.A.; Van Tendeloo, G.; Avdeev, V.V. |
| Title |
The chemical vapor infiltration of exfoliated graphite to produce carbon/carbon composites |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
| Volume |
49 |
Issue |
1 |
Pages |
147-153 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Chemical vapor infiltration was used for the production of carbon/carbon composites based on exfoliated graphite and pyrolytic carbon Two different exfoliated graphites compacted to densities of 0 05-0 4 g/cm(3) were used as a preform The influence of the synthesis conditions (temperature, pressure, time etc) on the degree of infiltration, the pyrolytic carbon morphology and the C/C composite characteristics was examined using Raman spectroscopy, scanning electron microscopy and low-temperature nitrogen adsorption (C) 2010 Elsevier Ltd All rights reserved |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Oxford |
Editor |
|
| Language |
|
Wos |
000284977500021 |
Publication Date |
2010-09-08 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0008-6223; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
6.337 |
Times cited |
7 |
Open Access |
|
| Notes |
Iap |
Approved |
Most recent IF: 6.337; 2011 IF: 5.378 |
| Call Number |
UA @ lucian @ c:irua:99185 |
Serial |
354 |
| Permanent link to this record |
| |
|
| |
| Author |
Gehrke, K.; Moshnyaga, V.; Samwer, K.; Lebedev, O.I.; Verbeeck, J.; Kirilenko, D.; Van Tendeloo, G. |
| Title |
Interface controlled electronic variations in correlated heterostructures |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
82 |
Issue |
11 |
Pages |
113101,1-113101,4 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
An interface modification of (LaCa)MnO3-BaTiO3 superlattices was found to massively influence magnetic and magnetotransport properties. Moreover it determines the crystal structure of the manganite layers, changing it from orthorhombic (Pnma) for the conventional superlattice (cSL), to rhombohedral (R3̅ c) for the modified one (mSL). While the cSL shows extremely nonlinear ac transport, the mSL is an electrically homogeneous material. The observations go beyond an oversimplified picture of dead interface layers and evidence the importance of electronic correlations at perovskite interfaces. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000281643200001 |
Publication Date |
2010-09-07 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
9 |
Open Access |
|
| Notes |
This work was supported by DFG via SFB 602, TPA2. |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
| Call Number |
UA @ lucian @ c:irua:84249UA @ admin @ c:irua:84249 |
Serial |
1691 |
| Permanent link to this record |
| |
|
| |
| Author |
Delville, R.; Schryvers, D. |
| Title |
Transmission electron microscopy study of combined precipitation of Ti2Ni(Pd) and Ti2Pd(Ni) in a Ti50Ni30Pd20 alloy |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Intermetallics |
Abbreviated Journal |
Intermetallics |
| Volume |
18 |
Issue |
12 |
Pages |
2353-2360 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
We report a new mode of precipitation in a B19 martensitic Ti50Ni30Pd20 shape memory alloy consisting of a central Ti2Ni(Pd) precipitate surrounded by an austenite area containing Ti2Pd(Ni) precipitates. The morphology and crystallography of the precipitation area is investigated using conventional and high resolution electron microscopy. In particular, the orientation relationship and the coherency strain between the Ti2Pd(Ni) precipitate and the surrounding retained B2 matrix are discussed. A study of local composition in relation with a ternary phase diagram using X-ray energy dispersive spectroscopy with a nanoprobe gives evidences of the formation mechanism. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Chicago, Ill. |
Editor |
|
| Language |
|
Wos |
000284447500014 |
Publication Date |
2010-09-04 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0966-9795; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.14 |
Times cited |
9 |
Open Access |
|
| Notes |
Multimat; Iap |
Approved |
Most recent IF: 3.14; 2010 IF: 2.335 |
| Call Number |
UA @ lucian @ c:irua:84473 |
Serial |
3714 |
| Permanent link to this record |
| |
|
| |
| Author |
Afanasov, I.M.; Van Tendeloo, G.; Mateev, A.T. |
| Title |
Production and structure of exfoliated graphite/coke composites modified by ZrO2 nanoparticles |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
New carbon materials |
Abbreviated Journal |
|
| Volume |
25 |
Issue |
4 |
Pages |
255-260 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Exfoliated graphite/coke composites modified by ZrO2 nanoparticles were produced using two different techniques and characterized by means of X-ray diffraction, scanning and transmission electron microscopy. In the first, low-density exfoliated graphite/coke blocks were dipped repeatedly and alternately in ZrO(NO3)2 and NH4OH solutions and subsequently heat treated at 1200°C in nitrogen to deposit thin layers of ZrO2 nanoparticles on the free surfaces of the carbon matrix. In the second, a mixture of expandable graphite, phenol-formaldehyde resin powder, and ZrOC2O4-modified fibrous cellulose in a sealed container was submitted to thermal shock at 900 °C followed by heat treatment at 1 200 °C in nitrogen to obtain the modified composites. The ZrO2 nanoparticles formed in the second technique were incorporated into the composites in three length scales: 6-30 nm-isolated nanoparticles and small blobs, 200-1000 nm-lengthy dendrite-like structures, and thin layer adhering to the surface of the 1-40 μm long cellulose carbon fibers. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000281534800003 |
Publication Date |
2010-09-02 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1872-5805; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
|
Times cited |
|
Open Access |
|
| Notes |
Iap-Vi |
Approved |
Most recent IF: NA |
| Call Number |
UA @ lucian @ c:irua:84438 |
Serial |
2721 |
| Permanent link to this record |
| |
|
| |
| Author |
Fang, C.M.; van Huis, M.A.; Zandbergen, H.W. |
| Title |
Stability and structures of the \epsilon-phases of iron nitrides and iron carbides from first principles |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Scripta materialia |
Abbreviated Journal |
Scripta Mater |
| Volume |
64 |
Issue |
3 |
Pages |
296-299 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
First-principles calculations were performed for the ε-phases and other iron carbides/nitrides with hexagonal close-packed Fe sublattices. Although these nitrides/carbides have similar crystal structures, they exhibit different chemical and physical properties. Relative to α-Fe, graphite and N2, all the ε-type nitrides are stable, while all the carbides are metastable. The lattice parameters of the ε-iron nitrides vary differently from those of the ε-carbides, as a function of the concentration of X (Xdouble bond; length as m-dashN, C). The structural relationships of ε-Fe2X with η-Fe2X and ζ-Fe2X are discussed. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Oxford |
Editor |
|
| Language |
|
Wos |
000285323300022 |
Publication Date |
2010-09-02 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1359-6462; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.747 |
Times cited |
29 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 3.747; 2011 IF: 2.699 |
| Call Number |
UA @ lucian @ c:irua:86974 |
Serial |
3120 |
| Permanent link to this record |
| |
|
| |
| Author |
Verbeeck, J.; Van Aert, S.; Zhang, L.; Haiyan, T.; Schattschneider, P.; Rosenauer, A. |
| Title |
Computational aspects in quantitative EELS |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Microscopy and microanalysis |
Abbreviated Journal |
Microsc Microanal |
| Volume |
16 |
Issue |
S:2 |
Pages |
240-241 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
|
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Cambridge, Mass. |
Editor |
|
| Language |
|
Wos |
|
Publication Date |
2010-08-26 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1431-9276;1435-8115; |
ISBN |
|
Additional Links |
UA library record |
| Impact Factor |
1.891 |
Times cited |
|
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 1.891; 2010 IF: 3.259 |
| Call Number |
UA @ lucian @ c:irua:96556UA @ admin @ c:irua:96556 |
Serial |
454 |
| Permanent link to this record |
| |
|
| |
| Author |
Tsirlin, A.A.; Abakumov, A.M.; Van Tendeloo, G.; Rosner, H. |
| Title |
Interplay of atomic displacement in the quantum magnet (CuCI)LaNb2O7 |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
82 |
Issue |
5 |
Pages |
054107,1-054107,12 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
We report on the crystal structure of the quantum magnet CuClLaNb2O7 that was controversially described with respect to its structural organization and magnetic behavior. Using high-resolution synchrotron powder x-ray diffraction, electron diffraction, transmission electron microscopy, and band-structure calculations, we solve the room-temperature structure of this compound -CuClLaNb2O7 and find two high-temperature polymorphs. The -CuClLaNb2O7 phase, stable above 640 K, is tetragonal with asub=3.889 Å, csub =11.738 Å, and the space group P4/mmm. In the -CuClLaNb2O7 structure, the Cu and Cl atoms are randomly displaced from the special positions along the 100 directions. The phase asub2asubcsub, space group Pbmm and the phase 2asub2asubcsub, space group Pbam are stable between 640 K and 500 K and below 500 K, respectively. The structural changes at 500 and 640 K are identified as order-disorder phase transitions. The displacement of the Cl atoms is frozen upon the → transformation while a cooperative tilting of the NbO6 octahedra in the phase further eliminates the disorder of the Cu atoms. The low-temperature -CuClLaNb2O7 structure thus combines the two types of the atomic displacements that interfere due to the bonding between the Cu atoms and the apical oxygens of the NbO6 octahedra. The precise structural information resolves the controversy between the previous computation-based models and provides the long-sought input for understanding CuClLaNb2O7 and related compounds with unusual magnetic properties. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000280849400001 |
Publication Date |
2010-08-12 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
13 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
| Call Number |
UA @ lucian @ c:irua:83991 |
Serial |
1706 |
| Permanent link to this record |
| |
|
| |
| Author |
Chen, L.; Kirilenko, D.; Stesmans, A.; Nguyen, X.S.; Binnemans, K.; Goderis, B.; Vanacken, J.; Lebedev, O.; Van Tendeloo, G.; Moshchalkov, V.V. |
| Title |
Symmetry and electronic states of Mn2+ in ZnS nanowires with mixed hexagonal and cubic stacking |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
| Volume |
97 |
Issue |
4 |
Pages |
041918,1-041918,3 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Electron spin resonance and electronic spectroscopy techniques were used to study the symmetry and electronic structure of Mn2+ dopants in solvothermally synthesized ZnS nanowires. The average diameter of ∼ 5 nm leads to the observable quantum confinement effects in the photoluminescence excitation spectra. The results clearly demonstrate the three symmetry locations of Mn2+ incorporation. Together with the inferred Mn2+ center densities, these data indicate a much higher efficiency of Mn2+ substitution in the nanowire sample with about two times larger diameter. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
|
Wos |
000281059200038 |
Publication Date |
2010-08-02 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0003-6951; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.411 |
Times cited |
5 |
Open Access |
|
| Notes |
Methusalem |
Approved |
Most recent IF: 3.411; 2010 IF: 3.841 |
| Call Number |
UA @ lucian @ c:irua:84869 |
Serial |
3403 |
| Permanent link to this record |
| |
|
| |
| Author |
Fang, C.M.; Sluiter, M.H.F.; van Huis, M.; Ande, C.K.; Zandbergen, H.W. |
| Title |
Origin of predominance of cementite among iron carbides in steel at elevated temperature |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
| Volume |
105 |
Issue |
5 |
Pages |
4 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
A long-standing challenge in physics is to understand why cementite is the predominant carbide in steel. Here we show that the prevalent formation of cementite can be explained only by considering its stability at elevated temperature. A systematic highly accurate quantum mechanical study was conducted on the stability of binary iron carbides. The calculations show that all the iron carbides are unstable relative to the elemental solids, -Fe and graphite. Apart from a cubic Fe23C6 phase, the energetically most favorable carbides exhibit hexagonal close-packed Fe sublattices. Finite-temperature analysis showed that contributions from lattice vibration and anomalous Curie-Weis magnetic ordering, rather than from the conventional lattice mismatch with the matrix, are the origin of the predominance of cementite during steel fabrication processes. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
|
Wos |
000280472900008 |
Publication Date |
2010-07-30 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0031-9007;1079-7114; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
8.462 |
Times cited |
65 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 8.462; 2010 IF: 7.622 |
| Call Number |
UA @ lucian @ c:irua:84064 |
Serial |
2526 |
| Permanent link to this record |
| |
|
| |
| Author |
Maignan, A.; Lebedev, O.I.; Van Tendeloo, G.; Martin, C.; Hebert, S. |
| Title |
Metal to insulator transition in the n-type hollandite vanadate Pb1.6V8O16 |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
82 |
Issue |
3 |
Pages |
035122, 1-035122,5 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The transport and magnetic measurements of polycrystalline Pb1.6V8O16 hollandite reveal a concomitant metal to insulator and antiferromagnetic transition at TMI≈140 K. A clear localization is found below TMI, evidenced by a rapid increase in the absolute value of the negative Seebeck coefficient. The structural study by x-ray and transmission electron microscopy confirms the hollandite structure and shows that no structural transition occurs at TMI, ruling out a possible charge orbital ordering. The negative Seebeck coefficient observed from 50 K up to 900 K, with values reaching S=−38 μV K−1 at 900 K, is explained by the electron doping of ∼1.4e− in the V empty t2g orbitals responsible for the bad metal resistivity (ρ900 K∼2 mΩ cm). As this S value is close to that obtained by considering only the spin and orbital degeneracies, it is expected that |S| for such vanadates will not be sensitive at high temperature to the t2g band filling |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000280366300002 |
Publication Date |
2010-07-27 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
10 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
| Call Number |
UA @ lucian @ c:irua:84065 |
Serial |
2009 |
| Permanent link to this record |
| |
|
| |
| Author |
Hadermann, J.; Abakumov, A.M.; Perkisas, T.; d' Hondt, H.; Tan, H.; Verbeeck, J.; Filonenko, V.P.; Antipov, E.V.; Van Tendeloo, G. |
| Title |
New perovskite-based manganite Pb2Mn2O5 |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
| Volume |
183 |
Issue |
183 |
Pages |
2190-2195 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
A new perovskite based compound Pb2Mn2O5 has been synthesized using a high pressure high temperature technique. The structure model of Pb2Mn2O5 is proposed based on electron diffraction, high angle annular dark field scanning transmission electron microscopy and high resolution transmission electron microscopy. The compound crystallizes in an orthorhombic unit cell with parameters a=5.736(1)Å≈√2a p p p (a p the parameter of the perovskite subcell) and space group Pnma. The Pb2Mn2O5 structure consists of quasi two-dimensional perovskite blocks separated by 1/2[110] p (1̄01) p crystallographic shear planes. The blocks are connected to each other by chains of edge-sharing MnO5 distorted tetragonal pyramids. The chains of MnO5 pyramids and the MnO6 octahedra of the perovskite blocks delimit six-sided tunnels accommodating double chains of Pb atoms. The tunnels and pyramidal chains adopt two mirror-related configurations (left L and right R) and layers consisting of chains and tunnels of the same configuration alternate in the structure according to an -LRLR-sequence. The sequence is sometimes locally violated by the appearance of -LL- or -RR-fragments. A scheme is proposed with a JahnTeller distortion of the MnO6 octahedra with two long and two short bonds lying in the ac plane, along two perpendicular orientations within this plane, forming a d-type pattern. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000282139600041 |
Publication Date |
2010-07-25 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0022-4596; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.299 |
Times cited |
8 |
Open Access |
|
| Notes |
Fwo; Bof; Esteem 026019 |
Approved |
Most recent IF: 2.299; 2010 IF: 2.261 |
| Call Number |
UA @ lucian @ c:irua:85472UA @ admin @ c:irua:85472 |
Serial |
2332 |
| Permanent link to this record |
| |
|
| |
| Author |
Idrissi, H.; Renard, K.; Schryvers, D.; Jacques, P.J. |
| Title |
On the relationship between the twin internal structure and the work-hardening rate of TWIP steels |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Scripta materialia |
Abbreviated Journal |
Scripta Mater |
| Volume |
63 |
Issue |
10 |
Pages |
961-964 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
FeMnC and FeMnSiAl TWIP steels deformed under the same conditions exhibit different work-hardening rates. The present study investigates the microstructure of plastically deformed FeMnC and FeMnSiAl samples, particularly the internal structure of the mechanically generated twins and their topology at the grain scale. Twins in the FeMnC steel are finer and full of sessile dislocations, rendering this material distinctly stronger with an improved work-hardening rate. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Oxford |
Editor |
|
| Language |
|
Wos |
000282461800003 |
Publication Date |
2010-07-20 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1359-6462; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.747 |
Times cited |
145 |
Open Access |
|
| Notes |
Iap |
Approved |
Most recent IF: 3.747; 2010 IF: 2.820 |
| Call Number |
UA @ lucian @ c:irua:84472 |
Serial |
2452 |
| Permanent link to this record |
| |
|
| |
| Author |
Figuerola, A.; van Huis, M.; Zanella, M.; Genovese, A.; Marras, S.; Falqui, A.; Zandbergen, H.W.; Cingolani, R.; Manna, L. |
| Title |
Epitaxial CdSe-Au nanocrystal heterostructures by thermal annealing |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Nano letters |
Abbreviated Journal |
Nano Lett |
| Volume |
10 |
Issue |
8 |
Pages |
3028-3036 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
|
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Washington |
Editor |
|
| Language |
|
Wos |
000280728900049 |
Publication Date |
2010-07-16 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1530-6984;1530-6992; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
12.712 |
Times cited |
112 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 12.712; 2010 IF: 12.219 |
| Call Number |
UA @ lucian @ c:irua:83995 |
Serial |
1069 |
| Permanent link to this record |
| |
|
| |
| Author |
Van Aert, S.; Chen, J.H.; van Dyck, D. |
| 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 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
| 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. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
| Language |
|
Wos |
000282562100008 |
Publication Date |
2010-07-15 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| 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 |
| |
|
| |
| Author |
Meilikhov, M.; Yusenko, K.; Esken, D.; Turner, S.; Van Tendeloo, G.; Fischer, R.A. |
| Title |
Metals@MOFs – loading MOFs with metal nanoparticles for hybrid functions |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
European journal of inorganic chemistry |
Abbreviated Journal |
Eur J Inorg Chem |
| Volume |
2010 |
Issue |
24 |
Pages |
3701-3714 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Metalorganic frameworks (MOFs) as well as porous coordination polymers (PCPs) are porous, organicinorganic hybrid solids with zeolite-like structures and properties. Due to their extraordinarily high surface area and well defined pore structure MOFs can be used for the stabilization of metal nanoparticles with adjustable size. The embedded metal nanoparticles are still accessible for other reagents due to the high porosity of the MOF systems. This fact makes metal@MOF systems especially interesting for heterogeneous catalysis, gas storage and chemical sensing. This review compiles the cases of metal nanoparticles supported by or embedded into MOFs reported so far and the main aspects and problems associated with these novel nanocomposite systems. The determination of the dispersion and the location of the particles at the MOF support, the control of the loading degree and its effect on the catalytic activity of the system are discussed as well as the partial degradation of the MOF structure upon particle formation. Examples of the introduction of stabilizing groups into the MOF network that direct the loading and can influence the size and shape of the embedded particles are still rare and point into the possible direction of future investigations. Finally, the formation of bimetallic nanoparticles, which are stabilized and supported by a MOF network, will also be reviewed. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Weinheim |
Editor |
|
| Language |
|
Wos |
000281684300001 |
Publication Date |
2010-07-09 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1434-1948; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.444 |
Times cited |
366 |
Open Access |
|
| Notes |
Esteem 026019 |
Approved |
Most recent IF: 2.444; 2010 IF: 2.910 |
| Call Number |
UA @ lucian @ c:irua:85495 |
Serial |
2014 |
| Permanent link to this record |
| |
|
| |
| Author |
Felten, A.; Gillon, X.; Gulas, M.; Pireaux, J.-J.; Ke, X.; Van Tendeloo, G.; Bittencourt, C.; Najafi, E.; Hitchcock, A.P. |
| Title |
Measuring point defect density in individual carbon nanotubes using polarization-dependent X-ray microscopy |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
| Volume |
4 |
Issue |
8 |
Pages |
4431-4436 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The presence of defects in carbon nanotubes strongly modifies their electrical, mechanical, and chemical properties. It was long thought undesirable, but recent experiments have shown that introduction of structural defects using ion or electron irradiation can lead to novel nanodevices. We demonstrate a method for detecting and quantifying point defect density in individual carbon nanotubes (CNTs) based on measuring the polarization dependence (linear dichroism) of the C 1s → π* transition at specific locations along individual CNTs with a scanning transmission X-ray microscope (STXM). We show that STXM can be used to probe defect density in individual CNTs with high spatial resolution. The quantitative relationship between ion dose, nanotube diameter, and defect density was explored by purposely irradiating selected sections of nanotubes with kiloelectronvolt (keV) Ga+ ions. Our results establish polarization-dependent X-ray microscopy as a new and very powerful characterization technique for carbon nanotubes and other anisotropic nanostructures. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000281052700014 |
Publication Date |
2010-07-07 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
13.942 |
Times cited |
26 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 13.942; 2010 IF: 9.865 |
| Call Number |
UA @ lucian @ c:irua:84734 |
Serial |
1966 |
| Permanent link to this record |
| |
|
| |
| Author |
Bertoni, G.; Verbeeck, J.; Brosens, F. |
| Title |
Fitting the momentum dependent loss function in EELS |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Microscopy research and technique |
Abbreviated Journal |
Microsc Res Techniq |
| Volume |
74 |
Issue |
3 |
Pages |
212-218 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Theory of quantum systems and complex systems |
| Abstract |
Momentum dependent inelastic plasmon scattering can be measured by electron energy loss in a transmission electron microscope. From energy filtered diffraction, the characteristic angle of scattering and the cutoff angle are measured, using a thin film of aluminum as a model test. Rather than deconvolving the data (as done in previous works), a fitting technique is used to extract the loss function from angular resolved spectra, starting from a simple model simulation. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
|
Wos |
000288095200002 |
Publication Date |
2010-07-06 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1059-910X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
1.147 |
Times cited |
6 |
Open Access |
|
| Notes |
Fwo; Esteem; Iap; Goa |
Approved |
Most recent IF: 1.147; 2011 IF: 1.792 |
| Call Number |
UA @ lucian @ c:irua:88782UA @ admin @ c:irua:88782 |
Serial |
1222 |
| Permanent link to this record |
| |
|
| |
| Author |
Cortes-Gil, R.; Parker, D.R.; Pitcher, M.J.; Hadermann, J.; Clarke, S.J. |
| Title |
Indifference of superconductivity and magnetism to size-mismatched cations in the layered iron arsenides Ba1-xNaxFe2As2 |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
| Volume |
22 |
Issue |
14 |
Pages |
4304-4311 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The evolution of the structure, magnetic ordering, and superconductivity in the series Ba(1-x)Na(x)Fe(2)As(2) is reported up to the limiting Na-rich composition with x = 0.6; the more Na-rich compositions are unstable at high temperatures with respect to competing phases. The magnetic and superconducting behaviors of the Bai,Na,Fe,As, members are similar to those of the betterinvestigated Ba(1-x)Na(x)Fe(2)As(2) analogues. This is evidently a consequence of the quantitatively similar evolution of the structure of the FeAs layers in the two series. In Ba(1-x)Na(x)Fe(2)As(2) antiferromagnetic order and an associated structural distortion are evident for x <= 0.35 and superconductivity is evident when x exceeds 0.2. For 0.4 <= x <= 0.6 bulk superconductivity is evident, and the long-range antiferromagnetically ordered state is completely suppressed. The maximum T(c) in the Ba(1-x)Na(x)Fe(2)As(2) series, as judged by the onset of diamagnetism, is 34K in Ba(0.6)Na(0.4)Fe(2)As(2). Despite the large mis-match in sizes between the two electropositive cations which separate the FeAs layers, there is no evidence for ordering of these cations on the length scale probed by electron diffraction. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| Language |
|
Wos |
000280005300027 |
Publication Date |
2010-07-02 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
9.466 |
Times cited |
31 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 9.466; 2010 IF: 6.400 |
| Call Number |
UA @ lucian @ c:irua:95594 |
Serial |
1601 |
| Permanent link to this record |
| |
|
| |
| Author |
Gorlé, C.; van Beeck, J.; Rambaud, P. |
| Title |
Dispersion in the wake of a rectangular building : validation of two Reynolds-averaged Navier-Stokes modelling approaches |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Boundary-layer meteorology |
Abbreviated Journal |
Bound-Lay Meteorol |
| Volume |
137 |
Issue |
1 |
Pages |
115-133 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
When modelling the turbulent dispersion of a passive tracer using Reynolds-averaged Navier-Stokes (RANS) simulations, two different approaches can be used. The first consists of solving a transport equation for a scalar, where the governing parameters are the mean velocity field and the turbulent diffusion coefficient, given by the ratio of the turbulent viscosity and the turbulent Schmidt number Sc (t) . The second approach uses a Lagrangian particle tracking algorithm, where the governing parameters are the mean velocity and the fluctuating velocity field, which is determined from the turbulence kinetic energy and the Lagrangian time T (L) . A comparison between the two approaches and wind-tunnel data for the dispersion in the wake of a rectangular building immersed in a neutral atmospheric boundary layer (ABL) is presented. Particular attention was paid to the influence of turbulence model parameters on the flow and concentration field. In addition, an approach to estimate Sc (t) and T (L) based on the calculated flow field is proposed. The results show that applying modified turbulence model constants to enable correct modelling of the ABL improves the prediction for the velocity and concentration fields when the modification is restricted to the region for which it was derived. The difference between simulated and measured concentrations is smaller than 25% or the uncertainty of the data on 76% of the points when solving the transport equation for a scalar with the proposed formulation for Sc (t) , and on 69% of the points when using the Lagrangian particle tracking with the proposed formulation for T (L) . |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Dordrecht |
Editor |
|
| Language |
|
Wos |
000281712500006 |
Publication Date |
2010-06-30 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0006-8314;1573-1472; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.573 |
Times cited |
16 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 2.573; 2010 IF: 1.879 |
| Call Number |
UA @ lucian @ c:irua:95570 |
Serial |
736 |
| Permanent link to this record |
| |
|
| |
| Author |
Khalil-Allafi, J.; Amin-Ahmadi, B. |
| Title |
Multiple-step martensitic transformations in the Ni51Ti49 single crystal |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Journal of materials science |
Abbreviated Journal |
J Mater Sci |
| Volume |
45 |
Issue |
23 |
Pages |
6440-6445 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Multiple-step martensitic transformations of an aged Ni51Ti49 single crystal using calorimetric method were investigated. Results show that for short aging times (1045 min) multiple-step martensitic transformations on cooling occur in two steps. Applying intermediate aging times (1.254 h) results in three steps and long aging times (more than 8 h) lead to two-step martensitic transformations again. This behavior has not been recognized in NiTi single crystals in literatures. It can be related to the heterogeneity of composition and stress fields around Ni4Ti3 precipitates. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000282429400021 |
Publication Date |
2010-06-30 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0022-2461;1573-4803; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.599 |
Times cited |
5 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 2.599; 2010 IF: 1.859 |
| Call Number |
UA @ lucian @ c:irua:122046 |
Serial |
2231 |
| Permanent link to this record |
| |
|
| |
| 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 |
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 |
|
| Corporate Author |
|
Thesis |
|
| 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 |
| |
|
| |
| Author |
Bekermann, D.; Gasparotto, A.; Barreca, D.; Devi, A.; Fischer, R.A.; Kete, M.; Štangar, U.L.; Lebedev, O.I.; Maccato, C.; Tondello, E.; Van Tendeloo, G. |
| Title |
ZnO nanorod arrays by plasma-enhanced CVD for light-activated functional applications |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
ChemPhysChem : a European journal of chemical physics and physical chemistry |
Abbreviated Journal |
Chemphyschem |
| Volume |
11 |
Issue |
11 |
Pages |
2337-2340 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Switch of the surface properties: Supported ZnO nanorod arrays with tailored roughness and aspect ratios are successfully synthesized by plasma-enhanced chemical vapor deposition. Such nanostructures exhibit significant superhydrophilic and photocatalytic properties tunable as a function of their morphological organization (see picture). This renders them promising building blocks for the fabrication of stimuli-responsive materials. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Weinheim |
Editor |
|
| Language |
|
Wos |
000281061500008 |
Publication Date |
2010-06-16 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1439-4235;1439-7641; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.075 |
Times cited |
38 |
Open Access |
|
| Notes |
Esteem 026019 |
Approved |
Most recent IF: 3.075; 2010 IF: 3.340 |
| Call Number |
UA @ lucian @ c:irua:84594 |
Serial |
3935 |
| Permanent link to this record |
| |
|
| |
| Author |
Bezjak, J.; Abakumov, A.M.; Recnik, A.; Krzmanc, M.M.; Jancar, B.; Suvorov, D. |
| Title |
The local structure and composition of Ba4Nb2O9-based oxycarbonates |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
| Volume |
183 |
Issue |
8 |
Pages |
1823-1828 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
X-ray powder-diffraction(XRD),high-resolutiontransmissionelectronmicroscopy(HRTEM),electron diffraction(ED),infraredspectroscopy(IR),thermogravimetry(TG)andmassspectroscopy(MS)were performedtoinvestigatethecompositionandthecrystalstructureoftetra-bariumdi-niobate(V) Ba4Nb2O9. TheTG,MSandIRstudiesrevealedthatthecompoundisahydratedoxycarbonate.Assuming that thecarbonatestoichiometricallyreplacesoxygen,thecompositionofthelow-temperature a-modification,obtainedbyslowcoolingfrom1100 1C, correspondstoBa4Nb2O8.8(CO3)0.2 0.1H2O, while thequenchedhigh-temperature g-modificationhastheBa4Nb2O8.42(CO3)0.58 0.38H2O composi- tion. The a-phase hasacompositeincommensuratelymodulatedstructureconsistingoftwomutually interacting[Ba]N and the[(Nb,)O3]N subsystems.Thecompositemodulatedcrystalstructureofthe a-phase canbedescribedwiththelatticeparameters a¼10.2688(1) A˚ , c¼2.82426(8) A˚ , q¼0.66774(2)c* and asuperspacegroup R3m(00g)0s. TheHRTEManalysisdemonstratesthenanoscale twinningofthetrigonaldomainsparalleltothe{100}crystallographicplanes.Thetwinningintroduces a one-dimensionaldisorderintothe[(Nb,)O3]N subsystem,whichresultsinanaverage P62c crystal structureofthe a-phase. Possibleplacesforthecarbonategroupinthestructurearediscussedusinga comparisonwithotherhexagonalperovskite-basedoxycarbonates. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000280620300013 |
Publication Date |
2010-06-14 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0022-4596; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.299 |
Times cited |
10 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 2.299; 2010 IF: 2.261 |
| Call Number |
UA @ lucian @ c:irua:84046 |
Serial |
1830 |
| Permanent link to this record |
| |
|
| |
| Author |
King, G.; Abakumov, A.M.; Hadermann, J.; Alekseeva, A.M.; Rozova, M.G.; Perkisas, T.; Woodward, P.M.; Van Tendeloo, G.; Antipov, E.V. |
| Title |
Crystal structure and phase transitions in Sr3WO6 |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
| Volume |
49 |
Issue |
13 |
Pages |
6058-6065 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The crystal structures of the beta and gamma polymorphs of Sr3WO6 and the gamma <->beta phase transition have been investigated using electron diffraction, synchrotron X-ray powder diffraction, and neutron powder diffraction. The gamma-Sr3WO6 polymorph is stable above T-c approximate to 470 K and adopts a monoclinically distorted double perovskite A(2)BB'O-6= Sr2SrWO6 structure (space group Cc, a = 10.2363(1)angstrom, b= 17.9007(1)angstrom, c= 11.9717(1)angstrom, beta=125.585(1)degrees at T= 1373 K, Z=12, corresponding to a = a(p)+1/2b(p) – 1/2c(p), b =3/2b(p) + 3/2c(p), c =-b(p) + c(p), a(p),b(p), c(p), lattice vectors of the parent Fm (3) over barm double perovskite structure). Upon cooling it undergoes a continuous phase transition into the triclinically distorted beta-Sr3WO6 phase (space group Cl, a = 10.09497(3)angstrom, b = 17.64748(5)angstrom, c = 11.81400(3)angstrom, alpha = 89.5470(2)degrees, beta= 125.4529(2)degrees, gamma =90.2889(2)degrees at T= 300 K). Both crystal structures of Sr3WO6 belong to a family of double perovskites with broken corner sharing connectivity of the octahedral framework. A remarkable feature of the gamma-Sr3WO6 structure is a non-cooperative rotation of the WO6 octahedra. One third of the WO6 octahedra are rotated by 45 about either the bp or the cp axis of the parent double perovskite structure. As a result, the WO6 octahedra do not share corners but instead share edges with the coordination polyhedra of the Sr cations at the B positions increasing their coordination number from 6 to 7 or 8. The crystal structure of the beta-phase is very close to the structure of the gamma-phase; decreasing symmetry upon the gamma ->beta transformation occurs because of unequal octahedral rotation angles about the bp and cp axes and increasing distortions of the WO6 octahedra. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Easton, Pa |
Editor |
|
| Language |
|
Wos |
000279211500036 |
Publication Date |
2010-06-09 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0020-1669;1520-510X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.857 |
Times cited |
18 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 4.857; 2010 IF: 4.326 |
| Call Number |
UA @ lucian @ c:irua:83877 |
Serial |
562 |
| Permanent link to this record |
