Records |
Author |
Fang, P.a.; Gu, H.; Wang, P.l.; Van Landuyt, J.; Vleugels, J.; Van der Biest, O.; |
Title |
Effect of powder coating on stabilizer distribution in CeO2-stabilized ZrO2 ceramics |
Type |
A1 Journal article |
Year |
2005 |
Publication |
Journal of the American Ceramic Society |
Abbreviated Journal |
J Am Ceram Soc |
Volume |
88 |
Issue |
7 |
Pages |
1929-1934 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The phase and microstructure relationship of 12 mol% CeO2-stabilized ZrO2 ceramics prepared from coated powder was investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersed Xray spectroscopy (EDS). As compared with the sample prepared with co-precipitated method, which exhibited a similar grain size distribution, the EDS analysis revealed that the powder coating induced a wide distribution of CeO2 solubility, which decreases monotonically with the increase of grain size. This variation of stabilizer content from grain to grain rendered many large grains in the monoclinic phase. Stronger cerium segregation to grain boundaries was observed between large grains, which often form thin amorphous films there. The inhomogeneous; CeO2 distribution keeps more tetragonal ZrO2 grains close to the phase boundary to facilitate the transforming toughness. Addition of an Al2O3 precursor in coated powders effectively raises the overall CeO2 stabilizer content in the grains and preserves more transformable tetragonal phase in the microstructure, which further enhanced the fracture toughness. The dependence of CeO2 solubility on grain size may be explained in a simple coating-controlled diffusion and growth process that deserves further investigation. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Columbus, Ohio |
Editor |
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Language |
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Wos |
000230128100040 |
Publication Date |
2005-06-23 |
Series Editor ![sorted by Series Editor field, ascending order (up)](img/sort_asc.gif) |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0002-7820;1551-2916; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.841 |
Times cited |
11 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.841; 2005 IF: 1.586 |
Call Number |
UA @ lucian @ c:irua:103156 |
Serial |
830 |
Permanent link to this record |
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Author |
Xu, T.; Wang, P.; Fang, P.; Kan, Y.; Chen, L.; Vleugels, J.; Van der Biest, O.; van Landuyt, J. |
Title |
Phase assembly and microstructure of CeO2-doped ZrO2 ceramics prepared by spark plasma sintering |
Type |
A1 Journal article |
Year |
2005 |
Publication |
Journal of the European Ceramic Society |
Abbreviated Journal |
J Eur Ceram Soc |
Volume |
25 |
Issue |
15 |
Pages |
3437-3442 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
CeO2-doped ZrO2, (8 mol%) starting powder was sintered by means of spark plasma sintering (SPS) at 1300 degrees C without holding time. The stability of the tetragonal ZrO2 phase in the Ce-ZrO2 ceramic sintered under strongly reducing conditions was investigated. The SPS sample consisted of monoclinic and tetragonal ZrO2 phase, with a volume ratio of two to one, as well as a trace amount of a Zr-Ce-O cubic solid solution phase. In contrast, the same powder sintered by hot-pressing in nitrogen at 1300 and 1500 degrees C for 1h showed no tetragonal ZrO2. Microstructural observation of the SPS ceramic by SEM and TEM revealed grains with and without twins. The reason for the appearance of the tetragonal phase in the SPS sample sintered under strongly reducing conditions is discussed. (c) 2004 Elsevier Ltd. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Barking |
Editor |
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Language |
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Wos |
000232172100006 |
Publication Date |
2004-12-16 |
Series Editor ![sorted by Series Editor field, ascending order (up)](img/sort_asc.gif) |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0955-2219; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.411 |
Times cited |
13 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.411; 2005 IF: 1.567 |
Call Number |
UA @ lucian @ c:irua:104065 |
Serial |
2576 |
Permanent link to this record |
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Author |
Shi, P.; Liu, M.; Ratkowsky, D.A.; Gielis, J.; Su, J.; Yu, X.; Wang, P.; Zhang, L.; Lin, Z.; Schrader, J. |
Title |
Leaf area-length allometry and its implications in leaf shape evolution |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Trees: structure and function |
Abbreviated Journal |
|
Volume |
33 |
Issue |
4 |
Pages |
1073-1085 |
Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
According to Thompson’s principle of similarity, the area of an object should be proportional to its length squared. However, leaf area–length data of some plants have been demonstrated not to follow the principle of similarity. We explore the reasons why the leaf area–length allometry deviates from the principle of similarity and examine whether there is a general model describing the relationship among leaf area, width and length. We sampled more than 11,800 leaves from six classes of woody and herbaceous plants and tested the leaf area–length allometry. We compared six mathematical models based on root-mean-square error as the measure of goodness-of-fit. The best supported model described a proportional relationship between leaf area and the product of leaf width and length (i.e., the Montgomery model). We found that the extent to which the leaf area–length allometry deviates from the principle of similarity depends upon the extent of variation of the ratio of leaf width to length. Estimates of the parameter of the Montgomery model ranged between 1/2, which corresponds to a triangular leaf with leaf length as its height and leaf width as its base, and π/4, which corresponds to an elliptical leaf with leaf length as its major axis and leaf width as its minor axis, for the six classes of plants. The narrow range in practice of the Montgomery parameter implies an evolutionary stability for the leaf area of large-leaved plants despite the fact that leaf shapes of these plants are rather different. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000475992600010 |
Publication Date |
2019-04-04 |
Series Editor ![sorted by Series Editor field, ascending order (up)](img/sort_asc.gif) |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0931-1890; 1432-2285 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:159970 |
Serial |
8170 |
Permanent link to this record |