| Records |
| Author |
He, Z.; Maurice, J.-L.; Gohier, A.; Lee, C.S.; Pribat, D.; Cojocaru, C.S. |
| Title |
Iron catalysts for the growth of carbon nanofibers : Fe, Fe3C or both? |
Type |
A1 Journal article |
Year  |
2011 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
| Volume |
23 |
Issue |
24 |
Pages |
5379-5387 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Iron is a widely used catalyst for the growth of carbon nanotubes (CNTs) or carbon nanofibers (CNFs) by catalytic chemical vapor deposition. However, both Fe and FeC compounds (generally, Fe3C) have been found to catalyze the growth of CNTs/CNFs, and a comparison study of their respective catalytic activities is still missing. Furthermore, the control of the crystal structure of iron-based catalysts, that is α-Fe or Fe3C, is still a challenge, which not only obscures our understanding of the growth mechanisms of CNTs/CNFs, but also complicates subsequent procedures, such as the removal of catalysts for better industrial applications. Here, we show a partial control of the phase of iron catalysts (α-Fe or Fe3C), obtained by varying the growth temperatures during the synthesis of carbon-based nanofibers/nanotubes in a plasma-enhanced chemical vapor deposition reactor. We also show that the structure of CNFs originating from Fe3C is bamboo-type, while that of CNFs originating from Fe is not. Moreover, we directly compare the growth rates of carbon-based nanofibers/nanotubes during the same experiments and find that CNFs/CNTs grown by α-Fe nanoparticles are longer than CNFs grown from Fe3C nanoparticles. The influence of the type of catalyst on the growth of CNFs is analyzed and the corresponding possible growth mechanisms, based on the different phases of the catalysts, are discussed. |
| Address |
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| Corporate Author |
|
Thesis |
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| Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| Language |
|
Wos |
000298197300014 |
Publication Date |
2011-11-10 |
| 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 |
91 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 9.466; 2011 IF: 7.286 |
| Call Number |
UA @ lucian @ c:irua:94297 |
Serial |
1748 |
| Permanent link to this record |
| |
|
| |
| Author |
Gasparotto, A.; Barreca, D.; Bekermann, D.; Devi, A.; Fischer, R.A.; Fornasiero, P.; Gombac, V.; Lebedev, O.I.; Maccato, C.; Montini, T.; Van Tendeloo, G.; Tondello, E. |
| Title |
F-doped Co3O4 photocatalysts for sustainable H2 generation from water/ethanol |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Journal of the American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
| Volume |
133 |
Issue |
48 |
Pages |
19362-19365 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
p-Type Co3O4 nanostructured films are synthesized by a plasma-assisted process and tested in the photocatalytic production of H2 from water/ethanol solutions under both near-UV and solar irradiation. It is demonstrated that the introduction of fluorine into p-type Co3O4 results in a remarkable performance improvement with respect to the corresponding undoped oxide, highlighting F-doped Co3O4 films as highly promising systems for hydrogen generation. Notably, the obtained yields were among the best ever reported for similar semiconductor-based photocatalytic processes. |
| Address |
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| Corporate Author |
|
Thesis |
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| Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| Language |
|
Wos |
000297606500027 |
Publication Date |
2011-11-04 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0002-7863;1520-5126; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
13.858 |
Times cited |
114 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 13.858; 2011 IF: 9.907 |
| Call Number |
UA @ lucian @ c:irua:93628 |
Serial |
1164 |
| Permanent link to this record |
| |
|
| |
| Author |
Novitskaya, M.; Makhnach, L.; Ivashkevich, L.; Pankov, V.; Klein, H.; Regeau, A.; David, J.; Gemmi, M.; Hadermann, J.; Strobel, P. |
| Title |
Synthesis, crystal structure and physico-chemical properties of the new quaternary oxide Sr5BiNi2O9.6 |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
| Volume |
184 |
Issue |
12 |
Pages |
3262-3268 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
A new black quaternary oxide Sr5BiNi2O9.6 was synthesized by solid state reaction at 1200 °C. Its structure was solved by electron crystallography and X-ray powder refinement, yielding a tetragonal structure with space group I4/mmm, a=5.3637 (2) Å, c=17.5541(5) Å, Z=4. The structure can be described as a stacking of (Bi,Sr)O rocksalt slabs and SrNiO3−δ perovskite slabs. The initial nickel valence is close to +3.1. Thermogravimetry and high-temperature oxygen coulometry showed that this compound has variable oxygen content as a function of temperature and oxygen pressure, and ultimately decomposes when heated in low oxygen pressure above 800 °C. It is a metallic conductor with n-type conduction. Its thermoelectric power was determined and found to be −20 and −38 μV/K at 300 and 650 °C, respectively. Magnetic measurements confirm the nickel valence close to +3 and show evidence of magnetic ordering at 20 K. |
| Address |
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| Corporate Author |
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Thesis |
|
| Publisher |
|
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000297662500021 |
Publication Date |
2011-10-20 |
| 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 |
4 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 2.299; 2011 IF: 2.159 |
| Call Number |
UA @ lucian @ c:irua:94016 |
Serial |
3451 |
| Permanent link to this record |
| |
|
| |
| Author |
Dixon, E.; Hadermann, J.; Ramos, S.; Goodwin, A.L.; Hayward, M.A. |
| Title |
Mn(I) in an extended oxide : the synthesis and characterization of La1-xCaxMnO2+\delta (0.6\leq x\leq1) |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Journal of the American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
| Volume |
133 |
Issue |
45 |
Pages |
18397-18405 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Reduction of La1xCaxMnO3 (0.6 ≤ x ≤ 1) perovskite phases with sodium hydride yields materials of composition La1xCaxMnO2+δ. The calcium-rich phases (x = 0.9, 1) adopt (La0.9Ca0.1)0.5Mn0.5O disordered rocksalt structures. However local structure analysis using reverse Monte Carlo refinement of models against pair distribution functions obtained from neutron total scattering data reveals lanthanum-rich La1xCaxMnO2+δ (x = 0.6, 0.67, 0.7) phases adopt disordered structures consisting of an intergrowth of sheets of MnO6 octahedra and sheets of MnO4 tetrahedra. X-ray absorption data confirm the presence of Mn(I) centers in La1xCaxMnO2+δ phases with x < 1. Low-temperature neutron diffraction data reveal La1xCaxMnO2+δ (x = 0.6, 0.67, 0.7) phases become antiferromagnetically ordered at low temperature. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| Language |
|
Wos |
000297381200065 |
Publication Date |
2011-10-14 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0002-7863;1520-5126; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
13.858 |
Times cited |
33 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 13.858; 2011 IF: 9.907 |
| Call Number |
UA @ lucian @ c:irua:94030 |
Serial |
2094 |
| Permanent link to this record |
| |
|
| |
| Author |
Romero-Pastor, J.; Duran, A.; Rodríguez-Navarro, A.B.; Van Grieken, R.; Cardell, C. |
| Title |
Compositional and quantitative microtextural characterization of historic paintings by micro-X-ray diffraction and Raman microscopy |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Analytical chemistry |
Abbreviated Journal |
|
| Volume |
83 |
Issue |
22 |
Pages |
8420-8428 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
This work shows the benefits of characterizing historic paintings via compositional and microtextural data from micro-X-ray diffraction (μ-XRD) combined with molecular information acquired with Raman microscopy (RM) along depth profiles in paint stratigraphies. The novel approach was applied to identify inorganic and organic components from paintings placed at the 14th century Islamic UniversityMadrasah Yusufiyyain Granada (Spain), the only Islamic University still standing from the time of Al-Andalus (Islamic Spain). The use of μ-XRD to obtain quantitative microtextural information of crystalline phases provided by two-dimensional diffraction patterns to recognize pigments nature and manufacture, and decay processes in complex paint cross sections, has not been reported yet. A simple Nasrid (14th century) palette made of gypsum, vermilion, and azurite mixed with glue was identified in polychromed stuccos. Here also a Christian intervention was found via the use of smalt, barite, hematite, Brunswick green and gold; oil was the binding media employed. On mural paintings and wood ceilings, more complex palettes dated to the 19th century were found, made of gypsum, anhydrite, barite, dolomite, calcite, lead white, hematite, minium, synthetic ultramarine blue, and black carbon. The identified binders were glue, egg yolk, and oil. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000296830200011 |
Publication Date |
2011-10-10 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0003-2700; 5206-882x |
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:92679 |
Serial |
7715 |
| Permanent link to this record |
| |
|
| |
| Author |
Smeulders, G.; van Oers, C.; Van Havenbergh, K.; Houthoofd, K.; Mertens, M.; Martens, J.A.; Bals, S.; Maes, B.U.W.; Meynen, V.; Cool, P. |
| Title |
Smart heating profiles for the synthesis of benzene bridged periodic mesoporous organosilicas |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Chemical engineering journal |
Abbreviated Journal |
Chem Eng J |
| Volume |
175 |
Issue |
|
Pages |
585-591 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA); Organic synthesis (ORSY) |
| Abstract |
In this study the effects of the heating rate and heating time on the formation of crystal-like benzene bridged periodic mesoporous organosilicas (PMOs) are investigated. The time needed to heat up an autoclave during the hydrothermal treatment has shown to be crucial in the synthesis of PMOs, while the total duration of heating gave rise to only minor differences. By choosing a smart heating profile, superior PMO materials can be obtained in a short time. Different heating profiles in a range from one minute to one hour are adopted by microwave equipment and compared with conventional heating methods. The heating rate has a large influence on the porosity characteristics and the uniformity of the obtained particles. Moreover, two new alternative synthetic strategies to adopt the smart heating profile are presented, in order to give some possible solutions for the expensive microwave equipment. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Lausanne |
Editor |
|
| Language |
|
Wos |
000297875900069 |
Publication Date |
2011-10-07 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1385-8947; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
6.216 |
Times cited |
7 |
Open Access |
|
| Notes |
Fwo; Goa-Bof |
Approved |
Most recent IF: 6.216; 2011 IF: 3.461 |
| Call Number |
UA @ lucian @ c:irua:93630 |
Serial |
3044 |
| Permanent link to this record |
| |
|
| |
| Author |
Neyts, E.C.; van Duin, A.C.T.; Bogaerts, A. |
| Title |
Changing chirality during single-walled carbon nanotube growth : a reactive molecular dynamics/Monte Carlo study |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Journal of the American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
| Volume |
133 |
Issue |
43 |
Pages |
17225-17231 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
The growth mechanism and chirality formation of a single-walled carbon nanotube (SWNT) on a surface-bound nickel nanocluster are investigated by hybrid reactive molecular dynamics/force-biased Monte Carlo simulations. The validity of the interatomic potential used, the so-called ReaxFF potential, for simulating catalytic SWNT growth is demonstrated. The SWNT growth process was found to be in agreement with previous studies and observed to proceed through a number of distinct steps, viz., the dissolution of carbon in the metallic particle, the surface segregation of carbon with the formation of aggregated carbon clusters on the surface, the formation of graphitic islands that grow into SWNT caps, and finally continued growth of the SWNT. Moreover, it is clearly illustrated in the present study that during the growth process, the carbon network is continuously restructured by a metal-mediated process, thereby healing many topological defects. It is also found that a cap can nucleate and disappear again, which was not observed in previous simulations. Encapsulation of the nanoparticle is observed to be prevented by the carbon network migrating as a whole over the cluster surface. Finally, for the first time, the chirality of the growing SWNT cap is observed to change from (11,0) over (9,3) to (7,7). It is demonstrated that this change in chirality is due to the metal-mediated restructuring process. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| Language |
|
Wos |
000297380900026 |
Publication Date |
2011-10-06 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0002-7863;1520-5126; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
13.858 |
Times cited |
116 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 13.858; 2011 IF: 9.907 |
| Call Number |
UA @ lucian @ c:irua:92043 |
Serial |
309 |
| Permanent link to this record |
| |
|
| |
| Author |
Bittencourt, C.; Navio, C.; Nicolay, A.; Ruelle, B.; Godfroid, T.; Snyders, R.; Colomer, J.-F.; Lagos, M.J.; Ke, X.; Van Tendeloo, G.; Suarez-Martinez, I.; Ewels, C.P. |
| Title |
Atomic oxygen functionalization of vertically aligned carbon nanotubes |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
| Volume |
115 |
Issue |
42 |
Pages |
20412-20418 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Vertically aligned multiwalled carbon nanotubes (v-MWCNTs) are functionalized using atomic oxygen generated in a microwave plasma. X-ray photoelectron spectroscopy depth profile analysis shows that the plasma treatment effectively grafts oxygen exclusively at the v-MWCNT tips. Electron microscopy shows that neither the vertical alignment nor the structure of v-MWCNTs were affected by the plasma treatment. Density functional calculations suggest assignment of XPS C 1s peaks at 286.6 and 287.5 eV, to epoxy and carbonyl functional groups, respectively. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| Language |
|
Wos |
000296205600009 |
Publication Date |
2011-10-04 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1932-7447;1932-7455; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.536 |
Times cited |
31 |
Open Access |
|
| Notes |
Iap |
Approved |
Most recent IF: 4.536; 2011 IF: 4.805 |
| Call Number |
UA @ lucian @ c:irua:91890 |
Serial |
174 |
| Permanent link to this record |
| |
|
| |
| Author |
Korneychik, O.E.; Batuk, M.; Abakumov, A.M.; Hadermann, J.; Rozova, M.G.; Sheptyakov, D.V.; Pokholok, K.V.; Filimonov, D.S.; Antipov, E.V. |
| Title |
Pb2.85Ba2.15Fe4SnO13 : a new member of the AnBnO3n-2 anion-deficient perovskite-based homologous series |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
| Volume |
184 |
Issue |
12 |
Pages |
3150-3157 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Pb2.85Ba2.15Fe4SnO13, a new n=5 member of the anion-deficient perovskite based AnBnO3n−2 (A=Pb, Ba, B=Fe, Sn) homologous series, was synthesized by the solid state method. The crystal structure of Pb2.85Ba2.15Fe4SnO13 was investigated using a combination of neutron powder diffraction, electron diffraction, high angle annular dark field scanning transmission electron microscopy and Mössbauer spectroscopy. It crystallizes in the Ammm space group with unit cell parameters a=5.7990(1) Å, b=4.04293(7) Å and c=26.9561(5) Å. The Pb2.85Ba2.15Fe4SnO13 structure consists of quasi two-dimensional perovskite blocks separated by 1/2[110](1̄01)p crystallographic shear (CS) planes. The corner-sharing FeO6 octahedra at the CS planes are transformed into edge-sharing FeO5 distorted tetragonal pyramids. The octahedral positions in the perovskite blocks between the CS planes are jointly taken up by Fe and Sn, with a preference of Sn towards the position at the center of the perovskite block. The chains of FeO5 pyramids and (Fe,Sn)O6 octahedra of the perovskite blocks delimit six-sided tunnels at the CS planes occupied by double chains of Pb atoms. The compound is antiferromagnetically ordered below TN=368±15 K. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000297662500003 |
Publication Date |
2011-09-30 |
| 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 |
7 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 2.299; 2011 IF: 2.159 |
| Call Number |
UA @ lucian @ c:irua:94013 |
Serial |
3550 |
| Permanent link to this record |
| |
|
| |
| Author |
Belik, A.A.; Abakumov, A.M.; Tsirlin, A.A.; Hadermann, J.; Kim, J.; Van Tendeloo, G.; Takayama-Muromachi, E. |
| Title |
Article Structure and magnetic properties of BiFe0.75Mn0.25O3 perovskite prepared at ambient and high pressure |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
| Volume |
23 |
Issue |
20 |
Pages |
4505-4514 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Solid solutions of BiFe1xMnxO3 (0.0 ≤ x ≤ 0.4) were prepared at ambient pressure and at 6 GPa. The ambient-pressure (AP) phases crystallize in space group R3c similarly to BiFeO3. The high-pressure (HP) phases crystallize in space group R3c for x = 0.05 and in space group Pnma for 0.15 ≤ x ≤ 0.4. The structure of HP-BiFe0.75Mn0.25O3 was investigated using synchrotron X-ray powder diffraction, electron diffraction, and transmission electron microscopy. HP-BiFe0.75Mn0.25O3 has a PbZrO3-related √2ap × 4ap × 2√2ap (ap is the parameter of the cubic perovskite subcell) superstructure with a = 5.60125(9) Å, b = 15.6610(2) Å, and c = 11.2515(2) Å similar to that of Bi0.82La0.18FeO3. A remarkable feature of this structure is the unconventional octahedral tilt system, with the primary ab0a tilt superimposed on pairwise clockwise and counterclockwise rotations around the b-axis according to the oioi sequence (o stands for out-of-phase tilt, and i stands for in-phase tilt). The (FeMn)O6 octahedra are distorted, with one longer metaloxygen bond (2.222.23 Å) that can be attributed to a compensation for covalent BiO bonding. Such bonding results in the localization of the lone electron pair on Bi3+ cations, as confirmed by electron localization function analysis. The relationship between HP-BiFe0.75Mn0.25O3 and antiferroelectric structures of PbZrO3 and NaNbO3 is discussed. On heating in air, HP-BiFe0.75Mn0.25O3 irreversibly transforms to AP-BiFe0.75Mn0.25O3 starting from about 600 K. Both AP and HP phases undergo an antiferromagnetic ordering at TN ≈ 485 and 520 K, respectively, and develop a weak net magnetic moment at low temperatures. Additionally, ceramic samples of AP-BiFe0.75Mn0.25O3 show a peculiar phenomenon of magnetization reversal. |
| Address |
|
| Corporate Author |
|
Thesis |
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| Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| Language |
|
Wos |
000295897400015 |
Publication Date |
2011-09-29 |
| 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 |
57 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 9.466; 2011 IF: 7.286 |
| Call Number |
UA @ lucian @ c:irua:93581 |
Serial |
151 |
| Permanent link to this record |
| |
|
| |
| Author |
Kontozova-Deutsch, V.; Deutsch, F.; Bencs, L.; Krata, A.; Van Grieken, R.; De Wael, K. |
| Title |
Optimization of the ion chromatographic quantification of airborne fluoride, acetate and formate in the Metropolitan Museum of Art, New York |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Talanta : the international journal of pure and applied analytical chemistry |
Abbreviated Journal |
Talanta |
| Volume |
86 |
Issue |
|
Pages |
372-376 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
Ion chromatographic (IC) methods have been compared in order to achieve an optimal separation of fluoride, acetate and formate under various elution conditions on two formerly introduced analytical columns (i and ii) and a novel one (iii): (i) an IonPac AS14 (250 mm × 4 mm I.D.), (ii) Allsep A-2 (150 mm × 4.6 mm I.D.), and (iii) an IC SI-50 4E (250 mm (length) × 4 mm (internal diameter – I.D.)). The IC conditions for the separation of the anions concerned were optimized on the IC SI-50 4E column. A near baseline separation of these anions was attained on the IonPac AS14, whereas the peaks of fluoride and acetate could not be resolved on the Allsep A-2. A baseline separation for the three anions was achieved on the IC SI-50 4E column, when applying an eluent mixture of 3.2 mmol/L Na2CO3 and 1.0 mmol/L NaHCO3 with a flow rate of 1.0 mL/min. The highest precision of 1.7, 3.0 and 2.8% and the best limits of detection (LODs) of 0.014, 0.22 and 0.17 mg/L for fluoride, acetate and formate, respectively, were obtained with the IC SI-50 4E column. Hence, this column was applied for the determination of the acetic and formic acid contents of air samples taken by means of passive gaseous sampling at the Metropolitan Museum of Art in New York, USA. Atmospheric concentrations of acetic and formic acid up to 1050 and 450 μg/m3, respectively, were found in non-aerated showcases of the museum. In galleries and outdoors, rather low levels of acetic and formic acid were detected with average concentrations of 50 and 10 μg/m3, respectively. The LOD data of acetate and formate on the IC SI-50 4E column correspond to around 0.5 μg/m3 for both acetic and formic acid in air samples. |
| Address |
|
| Corporate Author |
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Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000298126300048 |
Publication Date |
2011-09-24 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0039-9140; 1873-3573 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.162 |
Times cited |
19 |
Open Access |
|
| Notes |
; The authors gratefully acknowledge the support of Marco Leona and the staff of the Metropolitan Museum of Art in New York during the sampling campaigns. The technical assistance and advice by Dr. Takashi Kotsuka and Shodex Benelux are acknowledged as well. ; |
Approved |
Most recent IF: 4.162; 2011 IF: 3.794 |
| Call Number |
UA @ admin @ c:irua:92066 |
Serial |
5762 |
| Permanent link to this record |
| |
|
| |
| Author |
Verbruggen, S.W.; Ribbens, S.; Tytgat, T.; Hauchecorne, B.; Smits, M.; Meynen, V.; Cool, P.; Martens, J.A.; Lenaerts, S. |
| Title |
The benefit of glass bead supports for efficient gas phase photocatalysis : case study of a commercial and a synthesised photocatalyst |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Chemical engineering journal |
Abbreviated Journal |
Chem Eng J |
| Volume |
174 |
Issue |
1 |
Pages |
318-325 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Laboratory of adsorption and catalysis (LADCA); Sustainable Energy, Air and Water Technology (DuEL) |
| Abstract |
In the field of photocatalytic air purification, the immobilisation of catalyst particles on support surfaces without loss of photon efficiency is an important challenge. Therefore, an immobilisation method involving a one-step suspension coating of pre-synthesised photocatalysts on glass beads was applied. The various benefits are exemplified in the gas phase photodegradation of ethylene. Coating of glass beads is easy, fast, cheap and offers a more efficient alternative to bulk catalyst pellets. Furthermore, this coating procedure allows to use porous, pre-synthesised catalysts to their full potential, as the surface area and morphology of the initial powder is barely altered after coating, in strong contrast to pelletising. With this technique it became possible to study the gas phase photocatalytic activity of commercial titanium dioxide, trititanate nanotubes and mixed phase anatase/trititanate nanotubes in a packed bed reactor towards the degradation of ethylene without changing the catalyst properties. Coating of glass beads with the photocatalyst revealed the superior activity of the as-prepared nanotubes, compared to TiO2 Aerolyst® 7710 in gaseous phase. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000296950300041 |
Publication Date |
2011-09-17 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1385-8947; 1873-3212 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
6.216 |
Times cited |
39 |
Open Access |
|
| Notes |
; The author wishes to acknowledge the Research Foundation of Flanders (FWO) for the financial support. Evonik is greatly thanked for supplying the TiO<INF>2</ INF> Aerolyst (R) 7710 pellets. ; |
Approved |
Most recent IF: 6.216; 2011 IF: 3.461 |
| Call Number |
UA @ admin @ c:irua:93364 |
Serial |
5929 |
| Permanent link to this record |
| |
|
| |
| Author |
Kazakov, S.M.; Abakumov, A.M.; Perz-Mato, J.M.; Ovchinnikov, A.V.; Roslova, M.V.; Boltalin, A.I.; Morozov, I.V.; Antipov, E.V.; Van Tendeloo, G. |
| Title |
Uniform patterns of Fe-vacancy ordering in the Kx(Fe,Co)2-ySe2 superconductors |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
| Volume |
23 |
Issue |
19 |
Pages |
4311-4316 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The Fe-vacancy ordering patterns in the superconducting KxFe2ySe2 and nonsuperconducting Kx(Fe,Co)2ySe2 samples have been investigated by electron diffraction and high angle annular dark field scanning transmission electron microscopy. The Fe-vacancy ordering occurs in the ab plane of the parent ThCr2Si2-type structure, demonstrating two types of patterns. Superstructure I retains the tetragonal symmetry and can be described with the aI = bI = as√5 (as is the unit cell parameter of the parent ThCr2Si2-type structure) supercell and I4/m space group. Superstructure II reduces the symmetry to orthorhombic with the aII = as√2, bII = 2as√2 supercell and the Ibam space group. This type of superstructure is observed for the first time in KxFe2ySe2. The Fe-vacancy ordering is inhomogeneous: the disordered areas interleave with the superstructures I and II in the same crystallite. The observed superstructures represent the compositionally dependent uniform ordering patterns of two species (the Fe atoms and vacancies) on a square lattice. More complex uniform ordered configurations, including compositional stripes, can be predicted for different chemical compositions of the KxFe2ySe2 (0 < y < 0.5) solid solutions. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| Language |
|
Wos |
000295487800005 |
Publication Date |
2011-09-13 |
| 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 |
20 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 9.466; 2011 IF: 7.286 |
| Call Number |
UA @ lucian @ c:irua:92805 |
Serial |
3810 |
| Permanent link to this record |
| |
|
| |
| Author |
Esken, D.; Turner, S.; Wiktor, C.; Kalidindi, S.B.; Van Tendeloo, G.; Fischer, R.A. |
| Title |
GaN@ZIF-8 : selective formation of gallium nitride quantum dots inside a zinc methylimidazolate framework |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Journal of the American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
| Volume |
133 |
Issue |
41 |
Pages |
16370-16373 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The microporous zeolitic imidazolate framework [Zn(MeIM)2; ZIF-8; MeIM = imidazolate-2-methyl] was quantitatively loaded with trimethylamine gallane [(CH3)3NGaH3]. The obtained inclusion compound [(CH3)3NGaH3]@ZIF-8 reveals three precursor molecules per host cavity. Treatment with ammonia selectively yields the caged cyclotrigallazane intermediate (H2GaNH2)3@ZIF-8, and further annealing gives GaN@ZIF-8. This new composite material was characterized with FT-IR spectroscopy, solid-state NMR spectroscopy, powder X-ray diffraction, elemental analysis, (scanning) transmission electron microscopy combined with electron energy-loss spectroscopy, photoluminescence (PL) spectroscopy, and N2 sorption measurements. The data give evidence for the presence of GaN nanoparticles (13 nm) embedded in the cavities of ZIF-8, including a blue-shift of the PL emission band caused by the quantum size effect. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| Language |
|
Wos |
000295997500014 |
Publication Date |
2011-09-13 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0002-7863;1520-5126; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
13.858 |
Times cited |
82 |
Open Access |
|
| Notes |
Hercules |
Approved |
Most recent IF: 13.858; 2011 IF: 9.907 |
| Call Number |
UA @ lucian @ c:irua:93582 |
Serial |
1315 |
| Permanent link to this record |
| |
|
| |
| Author |
Vernimmen, J.; Meynen, V.; Herregods, S.J.F.; Mertens, M.; Lebedev, O.I.; Van Tendeloo, G.; Cool, P. |
| Title |
New insights in the formation of combined zeolitic/mesoporous materials by using a one-pot templating synthesis |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
European journal of inorganic chemistry |
Abbreviated Journal |
Eur J Inorg Chem |
| Volume |
|
Issue |
27 |
Pages |
4234-4240 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
| Abstract |
Zeolitic growth is often absent or occurs in separate phases when synthetic strategies based on the combination of zeolite templates and mesopore templating agents are applied. In this work, zeolitic growth and mesopore formation have been investigated at different temperatures by applying a one-pot templating approach, based on a TS-1 zeolite synthesis whereby part of the microtemplate (tetrapropylammonium hydroxide, TPAOH) is replaced by a mesotemplate (hexadecyltrimethylammonium bromide, CTMABr). Moreover, the synthesis duration and the molar ratio of the microtemplate/mesotemplate have also been studied. The different syntheses clearly show the inherent competitive mechanism between zeolitic growth and mesopore formation. These insights have led to the conclusion that by following a one-pot templating strategy with standard, nonexotic commercial templates, i.e. CTMABr and TPAOH, it is not possible to develop a true hierarchical mesoporous zeolite, meaning a mesoporous siliceous material with highly crystalline zeolitic walls. The resultant materials are instead combined zeolitic/mesoporous composite structures with, however, highly tuneable and controllable porosity characteristics. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
Weinheim |
Editor |
|
| Language |
|
Wos |
000296143500014 |
Publication Date |
2011-08-17 |
| 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 |
7 |
Open Access |
|
| Notes |
Fwo |
Approved |
Most recent IF: 2.444; 2011 IF: 3.049 |
| Call Number |
UA @ lucian @ c:irua:91574 |
Serial |
2315 |
| Permanent link to this record |
| |
|
| |
| Author |
Chen, L.-H.; Li, X.-Y.; Tian, G.; Li, Y.; Tan, H.-Y.; Van Tendeloo, G.; Zhu, G.-S.; Qiu, S.-L.; Yang, X.-Y.; Su, B.-L. |
| Title |
Multimodal zeolite-beta-based catalysts with a hierarchical, three-level pore structure |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Chemsuschem |
Abbreviated Journal |
Chemsuschem |
| Volume |
4 |
Issue |
10 |
Pages |
1452-1456 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Hole diggers: The hierarchically structured porous solid-acid catalyst described in this report possess a remarkable pore system, encompassing well-defined macrochannels, interconnected mesopores, intracrystalline mesopores, and tunable zeolite micropores. Importantly, the catalyst exhibits very strong acidity and superior catalytic activity for esterification reactions. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
Weinheim |
Editor |
|
| Language |
|
Wos |
000296497400009 |
Publication Date |
2011-08-16 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1864-5631; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
7.226 |
Times cited |
33 |
Open Access |
|
| Notes |
Iap |
Approved |
Most recent IF: 7.226; 2011 IF: 6.827 |
| Call Number |
UA @ lucian @ c:irua:93675 |
Serial |
2223 |
| Permanent link to this record |
| |
|
| |
| Author |
Delabie, A.; Sioncke, S.; Rip, J.; van Elshocht, S.; Caymax, M.; Pourtois, G.; Pierloot, K. |
| Title |
Mechanisms for the trimethylaluminum reaction in aluminum oxide atomic layer deposition on sulfur passivated germanium |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
| Volume |
115 |
Issue |
35 |
Pages |
17523-17532 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
Germanium combined with high-κ dielectrics is investigated for the next generations of CMOS devices. Therefore, we study reaction mechanisms for Al2O3 atomic layer deposition on sulfur passivated Ge using calculations based on density functional theory and total reflection X-ray fluorescence (TXRF). TXRF indicates 6 S/nm2 and 4 Al/nm2 after the first TMA/H2O reaction cycle, and growth inhibition from the second reaction cycle on. Calculations are performed on molecular clusters representing −GeSH surface sites. The calculations confirm that the TMA reaction does not affect the S content. On fully SH-terminated Ge, TMA favorably reacts with up to three −GeSH sites, resulting in a near tetrahedral Al coordination. Electron deficient structures with a GeS site shared between two Al atoms are proposed. The impact of the cluster size on the structures and reaction energetics is systematically investigated. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
|
| Language |
|
Wos |
000294386000037 |
Publication Date |
2011-08-01 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1932-7447;1932-7455; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.536 |
Times cited |
9 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 4.536; 2011 IF: 4.805 |
| Call Number |
UA @ lucian @ c:irua:91714 |
Serial |
1980 |
| Permanent link to this record |
| |
|
| |
| Author |
Lindner, H.; Murtazin, A.; Groh, S.; Niemax, K.; Bogaerts, A. |
| Title |
Simulation and experimental studies on plasma temperature, flow velocity, and injector diameter effects for an inductively coupled plasma |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
| Volume |
83 |
Issue |
24 |
Pages |
9260-9266 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
An inductively coupled plasma (ICP) is analyzed by means of experiments and numerical simulation. Important plasma properties are analyzed, namely, the effective temperature inside the central channel and the mean flow velocity inside the plasma. Furthermore, the effect of torches with different injector diameters is studied by the model. The temperature inside the central channel is determined from the end-on collected line-to-background ratio in dependence of the injector gas flow rates. Within the limits of 3% deviation, the results of the simulation and the experiments are in good agreement in the range of flow rates relevant for the analysis of relatively large droplets, i.e., 50 μm. The deviation increases for higher gas flow rates but stays below 6% for all flow rates studied. The velocity of the gas inside the coil region was determined by side-on analyte emission measurements with single monodisperse droplet introduction and by the analysis of the injector gas path lines in the simulation. In the downstream region significantly higher velocities were found than in the upstream region in both the simulation and the experiment. The quantitative values show good agreement in the downstream region. In the upstream region, deviations were found in the absolute values which can be attributed to the flow conditions in that region and because the methods used for velocity determination are not fully consistent. Eddy structures are found in the simulated flow lines. These affect strongly the way taken by the path lines of the injector gas and they can explain the very long analytical signals found in the experiments at low flow rates. Simulations were performed for different injector diameters in order to find conditions where good analyte transport and optimum signals can be expected. The results clearly show the existence of a transition flow rate which marks the lower limit for effective analyte transport conditions through the plasma. A rule-of-thumb equation was extracted from the results from which the transition flow rate can be estimated for different injector diameters and different injector gas compositions. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| Language |
|
Wos |
000297946900013 |
Publication Date |
2011-07-29 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0003-2700;1520-6882; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
6.32 |
Times cited |
34 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 6.32; 2011 IF: 5.856 |
| Call Number |
UA @ lucian @ c:irua:94001 |
Serial |
3009 |
| Permanent link to this record |
| |
|
| |
| Author |
Kontozova-Deutsch, V.; Deutsch, F.; Godoi, R.H.M.; Van Grieken, R.; De Wael, K. |
| Title |
Urban air pollutants and their micro effects on medieval stained glass windows |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Microchemical journal |
Abbreviated Journal |
Microchem J |
| Volume |
99 |
Issue |
2 |
Pages |
508-513 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
Levels of urban gaseous and particulate pollutants were investigated in the Cathedral of Cologne, Germany in the framework of the EU-project VIDRIO. The purpose of this study was to evaluate the influence of a protective double glazing system on the preservation of ancient stained glass windows by sampling at protected and unprotected windows (indoors, in the interspace and outdoor of the Cathedral). The interspace between the ancient stained glass window and the protective glazing is flushed in the Cathedral by indoor air, hence isolating the historic glass from the outdoor air and exposing it to indoor air on both sides of the glass panels. Concentrations of aggressive gaseous pollutants such as NO2, SO2, O3 and CO2 as well as elemental concentrations of bulk particles and relative abundances of single particles were surveyed at all sampling locations. Elemental concentrations in bulk particulate matter were found to be significantly lower inside the Cathedral in comparison to the outdoor air. This result is advantageous for the stained glass windows. Single particle analysis of the samples from Cologne showed also soil dust and organic particles as well as sulphates and nitrates, from which the latter two compounds are dangerous for the stained glass windows. On the base of the obtained results, it can be concluded that the protective glazing system in the Cathedral of Cologne can be considered as predominantly advantageous from both the gases' point of view (except for NO2-candles burning) and from the particles' point of view. |
| 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 |
|
| Language |
|
Wos |
000295770700053 |
Publication Date |
2011-07-23 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0026-265x; 0026-265x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.034 |
Times cited |
6 |
Open Access |
|
| Notes |
; This research was supported by the European Commission through the “VIDRIO-project”, contract no. EVK4-CT-2001-00045. Financial support is gratefully acknowledged. The authors acknowledge the assistance and advice during the experimental work given by the Dombauhutte team in Cologne, especially by Dr. Ulrike Brinkman and Gunter Hettinger. ; |
Approved |
Most recent IF: 3.034; 2011 IF: 3.048 |
| Call Number |
UA @ admin @ c:irua:91078 |
Serial |
5889 |
| Permanent link to this record |
| |
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| |
| Author |
Quintana, M.; Montellano, A.; Esau del Rio Castillo, A.; Van Tendeloo, G.; Bittencourt, C.; Prato, M. |
| Title |
Selective organic functionalization of graphene bulk or graphene edges |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Chemical communications |
Abbreviated Journal |
Chem Commun |
| Volume |
47 |
Issue |
33 |
Pages |
9330-9332 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Graphene sheets have been functionalized with a PAMAM dendron, finding that graphene can be efficiently functionalized all over the surface, or only at the edges, depending on the reactions used in the functionalization process. |
| Address |
|
| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000293648200010 |
Publication Date |
2011-07-20 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1359-7345;1364-548X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
6.319 |
Times cited |
84 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 6.319; 2011 IF: 6.169 |
| Call Number |
UA @ lucian @ c:irua:91892 |
Serial |
2968 |
| Permanent link to this record |
| |
|
| |
| Author |
King, G.; Abakumov, A.M.; Woodward, P.M.; Llobet, A.; Tsirlin, A.A.; Batuk, D.; Antipov, E.V. |
| Title |
The high-temperature polymorphs of K3AlF6 |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
| Volume |
50 |
Issue |
16 |
Pages |
7792-7801 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The crystal structures of the three high-temperature polymorphs of K3AlF6 have been solved from neutron powder diffraction, synchrotron X-ray powder diffraction, and electron diffraction data. The β-phase (stable between 132 and 153 °C) and γ-phase (stable between 153 to 306 °C) can be described as unusually complex superstructures of the double-perovskite structure (K2KAlF6) which result from noncooperative tilting of the AlF6 octahedra. The β-phase is tetragonal, space group I4/m, with lattice parameters of a = 13.3862(5) Å and c = 8.5617(3) Å (at 143 °C) and Z = 10. In this phase, one-fifth of the AlF6 octahedra are rotated about the c-axis by 45° while the other four-fifths remain untilted. The large 45° rotations result in edge sharing between these AlF6 octahedra and the neighboring K-centered polyhedra, resulting in pentagonal bipyramidal coordination for four-fifths of the K+ ions that reside on the B-sites of the perovskite structure. The remaining one-fifth of the K+ ions on the B-sites retain octahedral coordination. The γ-phase is orthorhombic, space group Fddd, with lattice parameters of a = 36.1276(4) Å, b = 17.1133(2) Å, and c = 12.0562(1) Å (at 225 °C) and Z = 48. In the γ-phase, one-sixth of the AlF6 octahedra are randomly rotated about one of two directions by 45° while the other five-sixths remain essentially untilted. These rotations result in two-thirds of the K+ ions on the B-site obtaining 7-fold coordination while the other one-third remain in octahedral coordination. The δ-phase adopts the ideal cubic double-perovskite structure, space group Fmm, with a = 8.5943(1) Å at 400 °C. However, pair distribution function analysis shows that locally the δ-phase is quite different from its long-range average crystal structure. The AlF6 octahedra undergo large-amplitude rotations which are accompanied by off-center displacements of the K+ ions that occupy the 12-coordinate A-sites. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
Easton, Pa |
Editor |
|
| Language |
|
Wos |
000293493100052 |
Publication Date |
2011-07-11 |
| 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 |
19 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 4.857; 2011 IF: 4.601 |
| Call Number |
UA @ lucian @ c:irua:91131 |
Serial |
1468 |
| Permanent link to this record |
| |
|
| |
| Author |
Hadermann, J.; Abakumov, A.M.; Turner, S.; Hafideddine, Z.; Khasanova, N.R.; Antipov, E.V.; Van Tendeloo, G. |
| Title |
Solving the structure of Li ion battery materials with precession electron diffraction : application to Li2CoPo4F |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
| Volume |
23 |
Issue |
15 |
Pages |
3540-3545 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The crystal structure of the Li2CoPO4F high-voltage cathode for Li ion rechargeable batteries has been completely solved from precession electron diffraction (PED) data, including the location of the Li atoms. The crystal structure consists of infinite chains of CoO4F2 octahedra sharing common edges and linked into a 3D framework by PO4 tetrahedra. The chains and phosphate anions together delimit tunnels filled with the Li atoms. This investigation demonstrates that PED can be successfully applied for obtaining structural information on a variety of Li-containing electrode materials even from single micrometer-sized crystallites. |
| Address |
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| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| Language |
|
Wos |
000293357100019 |
Publication Date |
2011-07-11 |
| 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 |
46 |
Open Access |
|
| Notes |
Fwo; Bof |
Approved |
Most recent IF: 9.466; 2011 IF: 7.286 |
| Call Number |
UA @ lucian @ c:irua:90357 |
Serial |
3053 |
| Permanent link to this record |
| |
|
| |
| Author |
Prituzhalov, V.A.; Ardashnikova, E.I.; Vinogradov, A.A.; Dolgikh, V.A.; Videau, J.-J.; Fargin, E.; Abakumov, A.M.; Tarakina, N.V.; Van Tendeloo, G. |
| Title |
New anion-conducting solid solutions Bi1-xTex(O,F)2+\delta (x > 0.5) and glassceramic material on their base |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Journal of fluorine chemistry |
Abbreviated Journal |
J Fluorine Chem |
| Volume |
132 |
Issue |
12 |
Pages |
1110-1116 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The anion-excess fluorite-like solid solutions with general composition Bi1−xTex(O,F)2+δ (x > 0.5) have been synthesized by a solid state reaction of TeO2, BiF3 and Bi2O3 at 873 K with following quenching. The homogeneity areas and polymorphism of the I ↔ IV Bi1−xTex(O,F)2+δ phases were investigated. The crystal structure of the low temperature IV-Bi1−xTex(O,F)2+δ phase has been solved using electron diffraction and X-ray powder diffraction (a = 11.53051(9) Å, S.G. Ia-3, RI = 0.046, RP = 0.041). Glass formation area in the Bi2O3BiF3TeO2 (10% TiO2) system was investigated. IVBi1−xTex(O,F)2+δ phase starts to crystallize at short-time (0.53 h) annealing of oxyfluoride glasses at temperatures above Tg (600615 K). The ionic conductivity of the crystalline Bi1−xTex(O,F)2+δ phase and corresponding glass-ceramics was investigated. Activation energy of conductivity Ea = 0.41(2) eV for the IV-Bi1−xTex(O,F)2+δ crystalline samples and Ea = 0.73 eV for the glass-ceramic samples were obtained. Investigation of the oxyfluoride samples with a constant cation ratio demonstrates essential influence of excess fluorine anions on the ionic conductivity. |
| Address |
|
| Corporate Author |
|
Thesis |
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| Publisher |
|
Place of Publication |
Lausanne |
Editor |
|
| Language |
|
Wos |
000296936300011 |
Publication Date |
2011-07-07 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0022-1139; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.101 |
Times cited |
2 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 2.101; 2011 IF: 2.033 |
| Call Number |
UA @ lucian @ c:irua:93687 |
Serial |
2305 |
| Permanent link to this record |
| |
|
| |
| Author |
Horemans, B.; Cardell, C.; Bencs, L.; Kontozova-Deutsch, V.; De Wael, K.; Van Grieken, R. |
| Title |
Evaluation of airborne particles at the Alhambra monument in Granada, Spain |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Microchemical journal |
Abbreviated Journal |
Microchem J |
| Volume |
99 |
Issue |
2 |
Pages |
429-438 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
As a part of an ongoing investigation regarding the air quality at the Alhambra monument (UNESCO World Cultural Heritage), indoor and outdoor atmospheric aerosols (PM1 and PM10-1) and pollutant gases (O3, NO2, SO2 and NH3) were studied during summer and winter. Bulk elements, ionic compounds and black carbon (BC) in aerosols were analyzed with X-ray fluorescence spectrometry, ion chromatography and aethalometry/reflectometry, respectively. Natural PM10-1 aerosols, such as carbonate-rich soil and sea salts, reacted with a typical urban atmosphere, producing a mixture of particulates with diverse chemical composition. The content/formation of secondary inorganic aerosols depended on the air temperature and absolute humidity. Ratios of typical mineral elements (i.e., Ti/Fe and Si/Fe) showed that Saharan dust events contribute to the composition of the observed mineral aerosol content. BC, V and Ni originated from diesel exhaust, while Cu, Cr, Pb and Zn came mainly from non-exhaust vehicular emissions. Weathering phenomena, such as blackening and pigment discoloration, which could arise from gradual aerosol deposition indoors, are discussed. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000295770700042 |
Publication Date |
2011-06-28 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0026-265x; 0026-265x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.034 |
Times cited |
39 |
Open Access |
|
| Notes |
; ; |
Approved |
Most recent IF: 3.034; 2011 IF: 3.048 |
| Call Number |
UA @ admin @ c:irua:91720 |
Serial |
5611 |
| Permanent link to this record |
| |
|
| |
| Author |
Alejo, ellys; Morales, M.C.; Nuñez, V.; Bencs, L.; Van Grieken, R.; van Espen, P. |
| Title |
Monitoring of tropospheric ozone in the ambient air with passive samplers |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Microchemical journal |
Abbreviated Journal |
|
| Volume |
99 |
Issue |
2 |
Pages |
383-387 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
Two sampling campaigns in suburban places in the north zone of Santa Clara city, Cuba, have been carried out on a weekly base with the use of Radiello passive diffusion tubes in order to monitor the tropospheric ozone (O3) levels in 2010. The first campaign was scheduled from February to April (cold season) and the second one in August and October (warm season), both of them at two sampling sites, i.e., Farm and School of Art Instructors. After aqueous extraction, the samples were analyzed by UVVIS spectrophotometry. A seasonal trend was observed with the maximum O3 concentrations in the cold season and the minimum levels in the warm season. Samples collected during the cold season showed the highest O3 levels. Higher levels were reached at the Farm site with average values of about 58 ± 12 μg/m3, which exceeded the limit of the Cuban Standard 99:1999. In the warm season, the O3 concentrations were similar for both sites, but lower than those observed in the cold season. The overall, seasonal average value was found to be 24 μg/m3. Despite the higher weekly average temperatures in August, the O3 concentrations during this month showed the lowest values of the whole sampling period, which finding is in agreement with that reported by the Meteorological Institute of Cuba. Mathematical models, based on the Cochrane-Orcutt algorithm, were fitted to the acquired data set to explain the change in the tropospheric ozone concentrations under various meteorological conditions during the two campaigns. The correlation coefficients for both the cold and the warm seasons demonstrated a strong correlation, i.e., 0.779 and 0.951, respectively. The high correlation of wind speed in the model from the first sampling campaign explains the sharp decrease in O3 concentrations at the SAI sampling site from the sixth week of sampling. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000295770700034 |
Publication Date |
2011-06-26 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0026-265x; 0026-265x |
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:93294 |
Serial |
8277 |
| Permanent link to this record |
| |
|
| |
| Author |
Nourbakhsh, A.; Cantoro, M.; Klekachev, A.V.; Pourtois, G.; Vosch, T.; Hofkens, J.; van der Veen, M.H.; Heyns, M.M.; de Gendt, S.; Sels, B.F. |
| Title |
Single layer vs bilayer graphene : a comparative study of the effects of oxygen plasma treatment on their electronic and optical properties |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
| Volume |
115 |
Issue |
33 |
Pages |
16619-16624 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
This contribution presents the effects of a mild O2 plasma treatment on the structural, optical, and electrical properties of single-layer (SLG) and bilayer graphene (BLG). Unexpectedly, we observe only photoluminescence in the SLG parts of a graphene flake composed of regions of various thickness upon O2 plasma treatment, whereas the BLG and few-layer graphene (FLG) parts remain optically unchanged. Confirmed with X-ray photoelectron spectroscopy (XPS) that O2 plasma induces epoxide and hydroxyl-like groups in graphene, density functional theory (DFT) calculations are carried out on representative epoxidized and hydroxylated SLG and BLG models to predict density of states (DOS) and band structures. Sufficiently oxidized SLG shows a bandgap and thus loss of semimetallic behavior, while oxidized BLG maintains its semimetallic behavior even at high oxygen density in agreement with the results of the photoluminescence spectroscopy (PL) experiments. DFT calculations confirm that the Fermi velocity in epoxidized BLG is remarkably comparable with that of pristine SLG, pointing to a similarity of electronic band structure. The similarity is also experimentally demonstrated by the electrical characterization of a plasma-treated BLG-FET. As expected from the electronegative oxygen adatoms in the graphene, epoxidized BLG presents conductive features typical of hole doping. Moreover, the electrical characteristics suggest band structures closely related to that of epoxidized graphene while deviating from that of hydroxylated graphene. Finally, upon O2 plasma treatment of BLG, the four-component 2D peak around 2700 cm1 in the Raman spectrum evolves into a single Lorentzian line, very like the 2D peak of pristine SLG. Summarizing, the data in this contribution recommend that a controlled O2 plasma treatment, which is compatible with CMOS process flow in contrast to wet chemical oxidation methods, provides an efficient and valuable technique to exploit the transport properties of the bottom layer of BLG. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| Language |
|
Wos |
000294077000047 |
Publication Date |
2011-06-24 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1932-7447;1932-7455; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.536 |
Times cited |
46 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 4.536; 2011 IF: 4.805 |
| Call Number |
UA @ lucian @ c:irua:91715 |
Serial |
3024 |
| Permanent link to this record |
| |
|
| |
| Author |
Shenderova, O.A.; Vlasov, I.I.; Turner, S.; Van Tendeloo, G.; Orlinskii, S.B.; Shiryaev, A.A.; Khomich, A.A.; Sulyanov, S.N.; Jelezko, F.; Wrachtrup, J. |
| Title |
Nitrogen control in nanodiamond produced by detonation shock-wave-assisted synthesis |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
| Volume |
115 |
Issue |
29 |
Pages |
14014-14024 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Development of efficient production methods of nanodiamond (ND) particles containing substitutional nitrogen and nitrogen-vacancy (NV) complexes remains an important goal in the nanodiamond community. ND synthesized from explosives is generally not among the preferred candidates for imaging applications owing to lack of optically active particles containing NV centers. In this paper, we have systematically studied representative classes of NDs produced by detonation shock wave conversion of different carbon precursor materials, namely, graphite and a graphite/hexogen mixture into ND, as well as ND produced from different combinations of explosives using different cooling methods (wet or dry cooling). We demonstrate that (i) the N content in nanodiamond particles can be controlled through a correct selection of the carbon precursor material (addition of graphite, explosives composition); (ii) particles larger than approximately 20 nm may contain in situ produced optically active NV centers, and (iii) in ND produced from explosives, NV centers are detected only in ND produced by wet synthesis. ND synthesized from a mixture of graphite/explosive contains the largest amount of NV centers formed during synthesis and thus deserves special attention. |
| Address |
|
| Corporate Author |
|
Thesis |
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| Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| Language |
|
Wos |
000292892500009 |
Publication Date |
2011-06-08 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1932-7447;1932-7455; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.536 |
Times cited |
54 |
Open Access |
|
| Notes |
Esteem 026019; Fwo |
Approved |
Most recent IF: 4.536; 2011 IF: 4.805 |
| Call Number |
UA @ lucian @ c:irua:91259 |
Serial |
2342 |
| Permanent link to this record |
| |
|
| |
| Author |
György, K.; Ajtony, Z.; van Meel, K.; Van Grieken, R.; Czitrovszky, A.; Bencs, L. |
| Title |
Fast heating induced impulse halogenation of refractory sample components in electrothermal atomic absorption spectrometry by direct injection of a liquid halogenating agent |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Talanta : the international journal of pure and applied analytical chemistry |
Abbreviated Journal |
|
| Volume |
85 |
Issue |
3 |
Pages |
1253-1259 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
A novel electrothermal atomic absorption spectrometry (ETAAS) method was developed for the halogenation of refractory sample components (Er, Nd and Nb) of lithium niobate (LiNbO3) and bismuth tellurite (Bi2TeO5) optical single crystals to overcome memory effects and carry-over. For this purpose, the cleaning step of a regular graphite furnace heating program was replaced with a halogenation cycle. In this cycle, after the graphite tube cooled to room temperature, a 20 μL aliquot of liquid carbon tetrachloride (CCl4) was dispensed with a conventional autosampler into the graphite tube. The CCl4 was partially dried at 80 °C under the mini-flow (40 cm3 min−1) condition of the Ar internal furnace gas (IFG), then the residue was decomposed (pyrolyzed) by fast furnace heating at 19002100 °C under interrupted flow of the IFG. This step was followed by a clean-out stage at 2100 °C under the maximum flow of the IFG. The advantage of the present method is that it does not require any alteration to the graphite furnace gas supply system in contrast to most of the formerly introduced halogenation techniques. The effectiveness of the halogenation method was verified with the determination of Er and Nd dopants in the optical crystals. In these analyses, a sensitivity decrease was observed, which was likely due to the enhanced deterioration of the graphite tube surface. Therefore, the application of mathematical correction (resloping) of the calibration was also required. The calibration curves were linear up to 1.5 and 10 μmol L−1 for Er and Nd, respectively. Characteristic masses of 18 and 241 pg and the limit of detection (LOD) values of 0.017 and 0.27 μmol L−1 were found for Er and Nd, respectively. These LOD data correspond to 0.68 μmol mol−1 Er and 11 μmol mol−1 Nd in solid bismuth tellurite samples. The analytical results were compared with those obtained by a conventional ETAAS method and validated with X-ray fluorescence spectrometry analysis. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000294092800006 |
Publication Date |
2011-05-27 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0039-9140; 1873-3573 |
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:91721 |
Serial |
7960 |
| Permanent link to this record |
| |
|
| |
| Author |
Jochems, P.; Satyawali, Y.; Diels, L.; Dejonghe, W. |
| Title |
Enzyme immobilization on/in polymeric membranes : status, challenges and perspectives in biocatalytic membrane reactors (BMRs) |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Green chemistry : cutting-edge research for a greener sustainable future |
Abbreviated Journal |
|
| Volume |
13 |
Issue |
7 |
Pages |
1609-1623 |
| Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
| Abstract |
Immobilization of enzymes is beneficial in terms of improving the process economics by enabling enzyme re-use and enhancing overall productivity and robustness. Increasingly, membranes are thought to be good supports for enzyme immobilization. These resulting biocatalytic membranes are integrated in reactors known as biocatalytic membrane reactors (BMRs) which enable the integration of biocatalysis and separation. Often the available commercial membranes require modifications to make them suitable for enzyme immobilization. Different immobilization techniques can be used on such suitable membranes, but no general rules exist for making a choice between them. Despite the advantages of BMR application, there are some issues which need to be addressed in order to achieve up-scaling of such systems. In this review, the different aspects of enzyme immobilization on membranes are discussed to show the complexity of this interdisciplinary technology. In addition, the existing issues which require further investigation are highlighted. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000292450600002 |
Publication Date |
2011-05-26 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1463-9262; 1463-9270 |
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:89567 |
Serial |
7930 |
| Permanent link to this record |
| |
|
| |
| Author |
Dixon, E.; Hadermann, J.; Hayward, M.A. |
| Title |
The synthesis and complex anion-vacancy ordered structure of La0.33Sr0.67MnO2.42 |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
| Volume |
184 |
Issue |
7 |
Pages |
1791-1799 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The low-temperature topotactic reduction of La0.33Sr0.67MnO3 with NaH results in the formation of La0.33Sr0.67MnO2.42. A combination of neutron powder and electron diffraction data show that La0.33Sr0.67MnO2.42 adopts a novel anion-vacancy ordered structure with a 6-layer OOTOOT' stacking sequence of the octahedral and tetrahedral layers (Pcmb, a=5.5804(1) Å, b=23.4104(7) Å, c=11.2441(3) Å). A significant concentration of anion vacancies at the anion site, which links neighbouring octahedral layers means that only 25% of the octahedral manganese coordination sites actually have 6-fold MnO6 coordination, the remainder being MnO5 square-based pyramidal sites. The chains of cooperatively twisted apex-linked MnO4 tetrahedra adopt an ordered -LRLR- arrangement within each tetrahedral layer. This is the first published example of a fully refined structure of this type which exhibits such intralayer ordering of the twisted tetrahedral chains. The rationale behind the contrasting structures of La0.33Sr0.67MnO2.42 and other previously reported reduced La1−xSrxMnO3−y phases is discussed. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000292718500032 |
Publication Date |
2011-05-26 |
| 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 |
|
Approved |
Most recent IF: 2.299; 2011 IF: 2.159 |
| Call Number |
UA @ lucian @ c:irua:90885 |
Serial |
3600 |
| Permanent link to this record |
