Records |
Author |
Gebrehiwot, N.T.; Azadi, H.; Taheri, F.; Van Passel, S. |
Title |
How participation in vegetables market affects livelihoods : empirical evidence from Northern Ethiopia |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Journal of international food and agribusiness marketing |
Abbreviated Journal |
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Volume |
30 |
Issue ![sorted by Issue field, descending order (down)](img/sort_desc.gif) |
2 |
Pages |
107-131 |
Keywords |
A1 Journal article; Economics; Engineering Management (ENM) |
Abstract |
Vegetable farmers face a number of challenges in marketing. Having first-hand information about vegetable marketing is essential to devise appropriate strategies aimed at enhancing the value of the vegetable chain. It was in line with this view that the study was conducted to characterize vegetable markets in Northern Ethiopia. In an effort to identify the factors influencing vegetable marketing among farmers, data were collected from 283 farm households who were selected using stratified random sampling. Furthermore, the data were triangulated through focus group discussion (FGD) and key informant interviews. Descriptive statistics and the binary logistic regression model were used to identify the variables and test the probability of their influence in regard to farmers decisions in vegetable marketing. From the 13 explanatory variables included in the binary logistic regression model, six predictors were found to be statistically significant in determining the effects of participation decision on vegetable market. These variables are as follows: household family size, total land holding of the household, amount of vegetable produced and marketed, use of irrigation technologies, contact with extension agents, and access to market information. Relying on a survey result and observations, the findings of the study indicated that vegetable marketing is significantly improving the livelihood of smallholder producers. |
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Place of Publication |
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Wos |
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Publication Date |
2017-12-01 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0897-4438 |
ISBN |
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Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:154141 |
Serial |
6210 |
Permanent link to this record |
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Author |
Dattoli, G.; Di Palma, E.; Gielis, J.; Licciardi, S. |
Title |
Parabolic trigonometry |
Type |
A1 Journal article |
Year |
2020 |
Publication |
International journal of applied and computational mathematics |
Abbreviated Journal |
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Volume |
6 |
Issue ![sorted by Issue field, descending order (down)](img/sort_desc.gif) |
2 |
Pages |
37 |
Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
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Corporate Author |
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Place of Publication |
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Wos |
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Publication Date |
2020-03-04 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2349-5103 |
ISBN |
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Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:167049 |
Serial |
6578 |
Permanent link to this record |
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Author |
Zhao, H.; Li, C.-F.; Yong, X.; Kumar, P.; Palma, B.; Hu, Z.-Y.; Van Tendeloo, G.; Siahrostami, S.; Larter, S.; Zheng, D.; Wang, S.; Chen, Z.; Kibria, M.G.; Hu, J. |
Title |
Coproduction of hydrogen and lactic acid from glucose photocatalysis on band-engineered Zn1-xCdxS homojunction |
Type |
A1 Journal article |
Year |
2021 |
Publication |
iScience |
Abbreviated Journal |
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Volume |
24 |
Issue ![sorted by Issue field, descending order (down)](img/sort_desc.gif) |
2 |
Pages |
102109 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Photocatalytic transformation of biomass into value-added chemicals coupled with co-production of hydrogen provides an explicit route to trap sunlight into the chemical bonds. Here, we demonstrate a rational design of Zn1-xCdxS solidsolution homojunction photocatalyst with a pseudo-periodic cubic zinc blende (ZB) and hexagonal wurtzite (WZ) structure for efficient glucose conversion to simultaneously produce hydrogen and lactic acid. The optimized Zn0.6Cd0.4S catalyst consists of a twinning superlattice, has a tuned bandgap, and displays excellent efficiency with respect to hydrogen generation (690 +/- 27.6 mu mol.h(-1).g(cat).(-1)), glucose conversion (similar to 90%), and lactic acid selectivity (similar to 87%) without any co-catalyst under visible light irradiation. The periodic WZ/ZB phase in twinning superlattice facilitates better charge separation, while superoxide radical (center dot O-2(-)) and photogenerated holes drive the glucose transformation and water oxidation reactions, respectively. This work demonstrates that rational photocatalyst design could realize an efficient and concomitant production of hydrogen and value-added chemicals from glucose photocatalysis. |
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Corporate Author |
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Wos |
000621266700080 |
Publication Date |
2021-01-28 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2589-0042 |
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 |
OpenAccess |
Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:176744 |
Serial |
6720 |
Permanent link to this record |
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Author |
Chen, L.; Elibol, K.; Cai, H.; Jiang, C.; Shi, W.; Chen, C.; Wang, H.S.; Wang, X.; Mu, X.; Li, C.; Watanabe, K.; Taniguchi, T.; Guo, Y.; Meyer, J.C.; Wang, H. |
Title |
Direct observation of layer-stacking and oriented wrinkles in multilayer hexagonal boron nitride |
Type |
A1 Journal article |
Year |
2021 |
Publication |
2d Materials |
Abbreviated Journal |
2D Mater |
Volume |
8 |
Issue ![sorted by Issue field, descending order (down)](img/sort_desc.gif) |
2 |
Pages |
024001 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Hexagonal boron nitride (h-BN) has long been recognized as an ideal substrate for electronic devices due to its dangling-bond-free surface, insulating nature and thermal/chemical stability. These properties of the h-BN multilayer are mainly determined by its lattice structure. Therefore, to analyse the lattice structure and orientation of h-BN crystals becomes important. Here, the stacking order and wrinkles of h-BN are investigated by transmission electron microscopy. It is experimentally confirmed that the layers in the h-BN flakes are arranged in the AA ' stacking. The wrinkles in a form of threefold network throughout the h-BN crystal are oriented along the armchair direction, and their formation mechanism was further explored by molecular dynamics simulations. Our findings provide a deep insight about the microstructure of h-BN and shed light on the structural design/electronic modulations of two-dimensional crystals. |
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Corporate Author |
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Place of Publication |
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Editor |
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Language |
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Wos |
000605937500001 |
Publication Date |
2020-12-16 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2053-1583 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.937 |
Times cited |
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Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 6.937 |
Call Number |
UA @ admin @ c:irua:174950 |
Serial |
6723 |
Permanent link to this record |
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Author |
Kashiwar, A.; Hahn, H.; Kubel, C. |
Title |
In situ TEM observation of cooperative grain rotations and the Bauschinger effect in nanocrystalline palladium |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Nanomaterials |
Abbreviated Journal |
Nanomaterials-Basel |
Volume |
11 |
Issue ![sorted by Issue field, descending order (down)](img/sort_desc.gif) |
2 |
Pages |
432 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
We report on cooperative grain rotation accompanied by a strong Bauschinger effect in nanocrystalline (nc) palladium thin film. A thin film of nc Pd was subjected to cyclic loading-unloading using in situ TEM nanomechanics, and the evolving microstructural characteristics were investigated with ADF-STEM imaging and quantitative ACOM-STEM analysis. ADF-STEM imaging revealed a partially reversible rotation of nanosized grains with a strong out-of-plane component during cyclic loading-unloading experiments. Sets of neighboring grains were shown to rotate cooperatively, one after the other, with increasing/decreasing strain. ACOM-STEM in conjunction with these experiments provided information on the crystallographic orientation of the rotating grains at different strain levels. Local Nye tensor analysis showed significantly different geometrically necessary dislocation (GND) density evolution within grains in close proximity, confirming a locally heterogeneous deformation response. The GND density analysis revealed the formation of dislocation pile-ups at grain boundaries (GBs), indicating the generation of back stresses during unloading. A statistical analysis of the orientation changes of individual grains showed the rotation of most grains without global texture development, which fits to both dislocation- and GB sliding-based mechanisms. Overall, our quantitative in situ experimental approach explores the roles of these different deformation mechanisms operating in nanocrystalline metals during cyclic loading. |
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 |
000622951500001 |
Publication Date |
2021-02-14 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2079-4991 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.553 |
Times cited |
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Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 3.553 |
Call Number |
UA @ admin @ c:irua:176770 |
Serial |
6729 |
Permanent link to this record |
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Author |
Yin, L.; Juneja, R.; Lindsay, L.; Pandey, T.; Parker, D.S. |
Title |
Semihard iron-based permanent-magnet materials |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Physical Review Applied |
Abbreviated Journal |
Phys Rev Appl |
Volume |
15 |
Issue ![sorted by Issue field, descending order (down)](img/sort_desc.gif) |
2 |
Pages |
024012 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Permanent magnets generally require a favorable, but difficult-to-achieve combination of high magnetization, Curie point, and magnetic anisotropy. Thus there have been few, if any, viable permanent magnets developed since the 1982 discovery of Nd2Fe14B [M. Sagawa, S. Fujimura, H. Yamamoto, Y. Matsuura, and S. Hirosawa, J. Appl. Phys. 57, 4094 (1985)]. Here we point out, both by direct first-principles calculations on the iron carbides and silicides Fe5C2, Fe5SiC, and Fe7C3 as well as a discussion of recent experimental findings, that there are numerous rare-earth-free iron-rich potential permanent-magnet materials with sufficient intrinsic magnetic properties to reasonably achieve room-temperature energy products of 20-25 MG Oe. This is substantially better than the performance of the best available rare-earth-free magnets based on ferrite, as well as shape-anisotropy-employing alnico. These magnets could plausibly fill, at low cost, the present performance “gap” [J. M. D. Coey, Scr. Mater. 67, 524 (2012)] between the best rare-earth-free magnets and rare-earth magnets such as Nd2Fe14B and Sm-Co. |
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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 |
000614707800002 |
Publication Date |
2021-02-05 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2331-7019 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.808 |
Times cited |
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Open Access |
Not_Open_Access |
Notes |
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Approved |
Most recent IF: 4.808 |
Call Number |
UA @ admin @ c:irua:176624 |
Serial |
6734 |
Permanent link to this record |
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Author |
van der Jeught, S.; Muyshondt, P.G.G.; Lobato, I. |
Title |
Optimized loss function in deep learning profilometry for improved prediction performance |
Type |
A1 Journal article |
Year |
2021 |
Publication |
JPhys Photonics |
Abbreviated Journal |
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Volume |
3 |
Issue ![sorted by Issue field, descending order (down)](img/sort_desc.gif) |
2 |
Pages |
024014 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Single-shot structured light profilometry (SLP) aims at reconstructing the 3D height map of an object from a single deformed fringe pattern and has long been the ultimate goal in fringe projection profilometry. Recently, deep learning was introduced into SLP setups to replace the task-specific algorithm of fringe demodulation with a dedicated neural network. Research on deep learning-based profilometry has made considerable progress in a short amount of time due to the rapid development of general neural network strategies and to the transferrable nature of deep learning techniques to a wide array of application fields. The selection of the employed loss function has received very little to no attention in the recently reported deep learning-based SLP setups. In this paper, we demonstrate the significant impact of loss function selection on height map prediction accuracy, we evaluate the performance of a range of commonly used loss functions and we propose a new mixed gradient loss function that yields a higher 3D surface reconstruction accuracy than any previously used loss functions. |
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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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Language |
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Wos |
000641030000001 |
Publication Date |
2021-03-18 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2515-7647 |
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 |
OpenAccess |
Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:178171 |
Serial |
6797 |
Permanent link to this record |
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Author |
Sebhatu, K.T.; Taheri, F.; Berhanu, T.; Maertens, M.; Van Passel, S.; D'Haese, M. |
Title |
Beyond focus : exploring variability of service provision of agricultural cooperatives |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Annals of public and cooperative economics |
Abbreviated Journal |
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Volume |
92 |
Issue ![sorted by Issue field, descending order (down)](img/sort_desc.gif) |
2 |
Pages |
207-231 |
Keywords |
A1 Journal article; Economics; Engineering Management (ENM) |
Abstract |
The wide array of services provided by agricultural cooperatives for their members is often not considered in academic studies. Addressing this gap in the literature, our paper explores the wide array of services provided by agricultural cooperatives and how these extend beyond those they were initially intended to provide. We study the extent and characteristics of service portfolios from 511 agricultural cooperatives in the Tigray region of Ethiopia. Results from two-limit Tobit models confirm that government and NGO-initiated cooperatives have a wide service portfolio compared to member-initiated cooperatives. In many of the studied cooperatives, the services they provide and their portfolios are more diverse than expected. Cooperatives seem to go beyond their focal areas of intervention. Also, those cooperatives that are more outward-oriented and where the chair has contact with other cooperatives or businesses, have a wider service portfolio. These results may help to explain the mixed findings on the impact of cooperative membership. |
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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 |
000583855500001 |
Publication Date |
2020-10-27 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1370-4788; 1467-8292 |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
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Times cited |
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Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:173574 |
Serial |
6916 |
Permanent link to this record |
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Author |
Tessema, G.A.; van der Borg, J.; Minale, A.S.; Van Rompaey, A.; Adgo, E.; Nyssen, J.; Asrese, K.; Van Passel, S.; Poesen, J. |
Title |
Inventory and assessment of geosites for geotourism development in the eastern and southeastern Lake Tana Region, Ethiopia |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Geoheritage |
Abbreviated Journal |
Geoheritage |
Volume |
13 |
Issue ![sorted by Issue field, descending order (down)](img/sort_desc.gif) |
2 |
Pages |
43 |
Keywords |
A1 Journal article; Engineering Management (ENM) |
Abstract |
Geotourism is a niche form of sustainable tourism that focuses on the geological and geomorphological features of an area, and the associated culture and biodiversity. Geosites are important resources for geotourism development. The eastern and southeastern Lake Tana region in Ethiopia has several geosites with a potential for geotourism development. Despite the diversity of potential geosites and the strategic location of the area in the Northern Tourist Circuit of Ethiopia, only a few attractions such as Lake Tana and the Blue Nile Falls are currently being visited. The objective of this paper is twofold: to inventory geosites in the eastern and southeastern Lake Tana region and assess their potential for geotourism development; and to propose a geosite inventory and assessment methodology for geotourism purposes with adaptations from previous studies. Several studies were reviewed and finally nine of them used as the main references to prepare the criteria, indicators, and sub-indicators for this study. The indicators used for assessing the potential of geosites relate to scientific, educational, scenic, recreational, protection, functional, and ecological values. This research presents the first inventory of geosites in the Lake Tana basin. A first list of 120 geosites has been inventoried. Further screening and clustering resulted in 61 geosites, of which 17 are viewpoints. Among the major geosites are waterfalls, a lake with islands and island monasteries, a flood plain, caves and cave churches, lava tubes, a mountain (shield volcano), volcanic plugs, volcanic cones, rock-hewn churches, and viewpoints. Quantitative assessment of the geotouristic potential of these geosites revealed that clustered (complex area) geosites received higher scientific, scenic, and recreational value scores. |
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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 |
000646574000002 |
Publication Date |
2021-05-03 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1867-2477 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.472 |
Times cited |
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Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 1.472 |
Call Number |
UA @ admin @ c:irua:178962 |
Serial |
6933 |
Permanent link to this record |
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Author |
Gezahegn, T.W.; Van Passel, S.; Berhanu, T.; D'Haese, M.; Maertens, M. |
Title |
Structural and institutional heterogeneity among agricultural cooperatives in Ethiopia : does it matter for farmers' welfare? |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Journal Of Agricultural And Resource Economics |
Abbreviated Journal |
J Agr Resour Econ |
Volume |
46 |
Issue ![sorted by Issue field, descending order (down)](img/sort_desc.gif) |
2 |
Pages |
325-342 |
Keywords |
A1 Journal article; Economics; Engineering Management (ENM) |
Abstract |
This paper analyzes how structural and institutional heterogeneity among irrigation cooperatives shapes the impact of membership on farmers' welfare in northern Ethiopia, using a novel heteroskedasticity-based identification strategy. More specifically, we estimate how cooperative characteristics influence members' income and poverty level. We find that stricter water use regulations have income-enhancing and poverty-reducing effects for farmers. We also find that farmers benefit more from membership in larger, younger, and bottom-up cooperatives initiated through grassroots collective action. Our findings have implications for irrigation development in Ethiopia and call for a better deliberation of organizational heterogeneity in cooperative impact studies |
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Place of Publication |
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Wos |
000656121100010 |
Publication Date |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1068-5502; 2327-8285 |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
1 |
Times cited |
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Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 1 |
Call Number |
UA @ admin @ c:irua:179190 |
Serial |
6945 |
Permanent link to this record |
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Author |
Wambacq, E.; Alloul, A.; Grunert, O.; Carrette, J.; Vermeir, P.; Spanoghe, J.; Sakarika, M.; Vlaeminck, S.E.; Haesaert, G. |
Title |
Aerobes and phototrophs as microbial organic fertilizers : exploring mineralization, fertilization and plant protection features |
Type |
A1 Journal article |
Year |
2022 |
Publication |
PLoS ONE |
Abbreviated Journal |
Plos One |
Volume |
17 |
Issue ![sorted by Issue field, descending order (down)](img/sort_desc.gif) |
2 |
Pages |
e0262497-15 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
Organic fertilizers and especially microbial biomass, also known as microbial fertilizer, can enable a paradigm shift to the conventional fertilizer-to-food chain, particularly when produced on secondary resources. Microbial fertilizers are already common practice (e.g. Bloom® and Synagro); yet microbial fertilizer blends to align the nutrient release profile to the plant’s needs are, thus far, unexplored. Moreover, most research only focuses on direct fertilization effects without considering added value properties, such as disease prevention. This study has explored three promising types of microbial fertilizers, namely dried biomass from a consortium of aerobic heterotrophic bacteria, a microalga (Arthrospira platensis) and a purple non-sulfur bacterium (Rhodobacter sphaeroides). Mineralization and nitrification experiments showed that the nitrogen mineralization profile can be tuned to the plant’s needs by blending microbial fertilizers, without having toxic ammonium peaks. In a pot trial with perennial ryegrass (Lolium perenne L.), the performance of microbial fertilizers was similar to the reference organic fertilizer, with cumulative dry matter yields of 5.6–6.7 g per pot. This was confirmed in a pot trial with tomato (Solanum lycopersicum L.), showing an average total plant length of 90–99 cm after a growing period of 62 days for the reference organic fertilizer and the microbial fertilizers. Moreover, tomato plants artificially infected with powdery mildew (Oidium neolycopersici), a devastating disease for the horticultural industry, showed reduced disease symptoms when A. platensis was present in the growing medium. These findings strengthen the application potential of this novel class of organic fertilizers in the bioeconomy, with a promising match between nutrient mineralization and plant requirements as well as added value in crop protection. |
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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 |
000775890100025 |
Publication Date |
2022-02-02 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1932-6203 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.7 |
Times cited |
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Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 3.7 |
Call Number |
UA @ admin @ c:irua:185568 |
Serial |
7122 |
Permanent link to this record |
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Author |
Van Winckel, T.; Ngo, N.; Sturm, B.; Al-Omari, A.; Wett, B.; Bott, C.; Vlaeminck, S.E.; De Clippeleir, H. |
Title |
Enhancing bioflocculation in high-rate activated sludge improves effluent quality yet increases sensitivity to surface overflow rate |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Chemosphere |
Abbreviated Journal |
Chemosphere |
Volume |
308 |
Issue ![sorted by Issue field, descending order (down)](img/sort_desc.gif) |
2 |
Pages |
136294-11 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
High-rate activated sludge (HRAS) relies on good bioflocculation and subsequent solid-liquid separation to maximize the capture of organics. However, full-scale applications often suffer from poor and unpredictable effluent suspended solids (ESS). While the biological aspects of bioflocculation are thoroughly investigated, the effects of fines (settling velocity < 0.6 m3/m2/h), shear and surface overflow rate (SOR) are unclear. This work tackled the impact of fines, shear, and SOR on the ESS in absence of settleable influent solids. This was assessed on a full-scale HRAS step-feed (SF) and pilot-scale HRAS contact-stabilization (CS) configuration using batch settling tests, controlled clarifier experiments, and continuous operation of reactors. Fines contributed up to 25% of the ESS in the full-scale SF configuration. ESS decreased up to 30 mg TSS/L when bioflocculation was enhanced with the CS configuration. The feast-famine regime applied in CS promoted the production of high-quality extracellular polymeric substances (EPS). However, this resulted in a narrow and unfavorable settling velocity distribution, with 50% ± 5% of the sludge mass settling between 0.6 and 1.5 m3/m2/h, thus increasing sensitivity towards SOR changes. A low shear environment (20 s−1) before the clarifier for at least one min was enough to ensure the best possible settling velocity distribution, regardless of prior shear conditions. Overall, this paper provides a more complete view on the drivers of ESS in HRAS systems, creating the foundation for the design of effective HRAS clarifiers. Tangible recommendations are given on how to manage fines and establish the optimal settling velocity of the sludge. |
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Publisher |
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Place of Publication |
|
Editor |
|
Language |
|
Wos |
000863979600006 |
Publication Date |
2022-09-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0045-6535; 1879-1298 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
8.8 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 8.8 |
Call Number |
UA @ admin @ c:irua:190187 |
Serial |
7154 |
Permanent link to this record |
|
|
|
Author |
Cui, Z.; Meng, S.; Yi, Y.; Jafarzadeh, A.; Li, S.; Neyts, E.C.; Hao, Y.; Li, L.; Zhang, X.; Wang, X.; Bogaerts, A. |
Title |
Plasma-catalytic methanol synthesis from CO₂ hydrogenation over a supported Cu cluster catalyst : insights into the reaction mechanism |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Acs Catalysis |
Abbreviated Journal |
Acs Catal |
Volume |
12 |
Issue ![sorted by Issue field, descending order (down)](img/sort_desc.gif) |
2 |
Pages |
1326-1337 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Plasma-catalytic CO, hydrogenation for methanol production is gaining increasing interest, but our understanding of its reaction mechanism remains primitive. We present a combined experimental/computational study on plasma-catalytic CO, hydrogenation to CH3OH over a size-selected Cu/gamma-Al2O3 catalyst. Our experiments demonstrate a synergistic effect between the Cu/gamma-Al2O3 catalyst and the CO2/H-2 plasma, achieving a CO2 conversion of 10% at 4 wt % Cu loading and a CH3OH selectivity near 50% further rising to 65% with H2O addition (for a H2O/CO2 ratio of 1). Furthermore, the energy consumption for CH3OH production was more than 20 times lower than with plasma only. We carried out density functional theory calculations over a Cu-13/gamma-Al2O3 model, which reveal that the interfacial sites of the Cu-13 cluster and gamma-Al2O3 support show a bifunctional effect: they not only activate the CO2 molecules but also strongly adsorb key intermediates to promote their hydrogenation further. Reactive plasma species can regulate the catalyst surface reactions via the Eley-Rideal (E-R) mechanism, which accelerates the hydrogenation process and promotes the generation of the key intermediates. H2O can promote the CH3OH desorption by competitive adsorption over the Cu-13/gamma-Al2O3 surface. This study provides new insights into CO2 hydrogenation through plasma catalysis, and it provides inspiration for the conversion of some other small molecules (CH4, N-2, CO, etc.) by plasma catalysis using supported-metal clusters. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000742735600001 |
Publication Date |
2022-01-07 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2155-5435 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.9 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 12.9 |
Call Number |
UA @ admin @ c:irua:186416 |
Serial |
7192 |
Permanent link to this record |
|
|
|
Author |
Byrnes, I.; Rossbach, L.M.; Jaroszewicz, J.; Grolimund, D.; Sanchez, D.F.; Gomez-Gonzalez, M.A.; Nuyts, G.; Reinoso-Maset, E.; Janssens, K.; Salbu, B.; Brede, D.A.; Lind, O.C. |
Title |
Synchrotron XRF and histological analyses identify damage to digestive tract of uranium NP-exposed Daphnia magna |
Type |
A1 Journal article |
Year |
2023 |
Publication |
Environmental science and technology |
Abbreviated Journal |
|
Volume |
57 |
Issue ![sorted by Issue field, descending order (down)](img/sort_desc.gif) |
2 |
Pages |
1071-1079 |
Keywords |
A1 Journal article; Antwerp X-ray Imaging and Spectroscopy (AXIS) |
Abstract |
Micro-and nanoscopic X-ray techniques were used to investigate the relationship between uranium (U) tissue distributions and adverse effects to the digestive tract of aquatic model organism Daphnia magna following uranium nanoparticle (UNP) exposure. X-ray absorption computed tomography measure-ments of intact daphnids exposed to sublethal concentrations of UNPs or a U reference solution (URef) showed adverse morphological changes to the midgut and the hepatic ceca. Histological analyses of exposed organisms revealed a high proportion of abnormal and irregularly shaped intestinal epithelial cells. Disruption of the hepatic ceca and midgut epithelial tissues implied digestive functions and intestinal barriers were compro-mised. Synchrotron-based micro X-ray fluorescence (XRF) elemental mapping identified U co-localized with morphological changes, with substantial accumulation of U in the lumen as well as in the epithelial tissues. Utilizing high-resolution nano-XRF, 400-1000 nm sized U particulates could be identified throughout the midgut and within hepatic ceca cells, coinciding with tissue damages. The results highlight disruption of intestinal function as an important mode of action of acute U toxicity in D. magna and that midgut epithelial cells as well as the hepatic ceca are key target organs. |
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000910915100001 |
Publication Date |
2023-01-04 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0013-936x; 1520-5851 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
11.4 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 11.4; 2023 IF: 6.198 |
Call Number |
UA @ admin @ c:irua:193478 |
Serial |
7342 |
Permanent link to this record |
|
|
|
Author |
Siriwardane, E.M.D.; Demiroglu, I.; Sevik, C.; Cakir, D. |
Title |
Achieving Fast Kinetics and Enhanced Li Storage Capacity for Ti3C2O2 by Intercalation of Quinone Molecules |
Type |
A1 Journal article |
Year |
2019 |
Publication |
ACS applied energy materials |
Abbreviated Journal |
|
Volume |
2 |
Issue ![sorted by Issue field, descending order (down)](img/sort_desc.gif) |
2 |
Pages |
1251-1258 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Using first-principles calculations, we demonstrated that high lithium storage capacity and fast kinetics are achieved for Ti3C2O2 by preintercalating organic molecules. As a proof-of-concept, two different quinone molecules, namely 1,4-benzoquinone (C6H4O2) and tetrafluoro-1,4-benzoquinone (C6F4O2) were selected as the molecular linkers to demonstrate the feasibility of this interlayer engineering strategy for energy storage. As compared to Ti3C2O2 bilayer without linker molecules, our pillared structures facilitate a much faster ion transport, promising a higher charge/discharge rate for Li. For example, while the diffusion barrier of a single Li ion within pristine Ti3C2O2 bilayer is at least 1.0 eV, it becomes 0.3 eV in pillared structures, which is comparable and even lower than that of commercial materials. At high Li concentrations, the calculated diffusion barriers are as low as 0.4 eV. Out-of-plane migration of Li ions is hindered due to large barrier energy with a value of around 1-1.35 eV. Concerning storage capacity, we can only intercalate one monolayer of Li within pristine Ti3C2O2 bilayer. In contrast, pillared structures offer significantly higher storage capacity. Our calculations showed that at least two layers of Li can be intercalated between Ti3C2O2 layers without forming bulk Li and losing the pillared structure upon Li loading/unloading. A small change in the in-plane lattice parameters (<0.5%) and volume (<1.0%) and ab initio molecular dynamics simulations prove the stability of the pillared structures against Li intercalation and thermal effects. Intercalated molecules avoid the large contraction/expansion of the whole structure, which is one of the key problems in electrochemical energy storage. Pillared structures allow us to realize electrodes with high capacity and fast kinetics. Our results open new research paths for improving the performance of not only MXenes but also other layered materials for supercapacitor and battery applications. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000459948900037 |
Publication Date |
2019-01-04 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2574-0962 |
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:193759 |
Serial |
7414 |
Permanent link to this record |
|
|
|
Author |
Rojas, C.M.; Artaxo, P.; Van Grieken, R. |
Title |
Aerosols in Santiago de Chile : a study using receptor modeling with X-ray fluorescence and single particle analysis |
Type |
A1 Journal article |
Year |
1990 |
Publication |
Atmospheric environment: part B : urban atmosphere |
Abbreviated Journal |
|
Volume |
24 |
Issue ![sorted by Issue field, descending order (down)](img/sort_desc.gif) |
2 |
Pages |
227-241 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Between 15 January and 26 February 1987, 51 fine and coarse mode aerosol samples were collected at the Universidad de Santiago de Chile Planetarium using a dichotomous sampler. The samples were analyzed by X-ray fluorescence for up to 17 elements (Mg, Al, Si, P, S, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br and Pb). Aerosol particles were individually studied by Electron Probe Microanalysis (EPMA) and Laser Microprobe Mass Analysis (LAMMA). The data set consisting of aerosol elemental concentrations and meteorological variables was subjected to Principal Factor Analysis (PFA), allowing the identification of six fine mode particle source classes (soil, industrial, sulfate particles, traffic, residual oil, wood-burnings), and five coarse mode particle source classes (soil, industrial, traffic, residual oil, sulfate particles). Both PFA solutions explained about 81 and 90% of the total variance in the data set, respectively. The regression of elemental mass concentrations on the Absolute Principal Factor Scores allowed the estimation of the contribution of the different source classes to the Santiago aerosol. Within the fine fraction, secondary SO42− particles were responsible for about 49% of the fine mode aerosol mass concentration, while 26, 13, 6.4 and 5.6% were attributed to wood-burning/car exhausts, residual oil combustion, soil dust/metallurgical, and soil dust/wood-burning releases, respectively. The coarse fraction source apportionment was mainly dominated by soil dust, accounting for 74% of the coarse mode aerosol mass concentration. A composite of soil dust and industrial release accounted for 13%; a composite of secondary sulfates contributed with 9%; a composite of soil dust and automotive emissions, and secondary sulfates were responsible for 4 and 0.03% of the coarse aerosol mass concentration, respectively. EPMA results are in satisfactory agreement with those from the bulk analysis and allowed the identification of eight particle types in both fine and coarse mode aerosols, pertaining to different source classes, namely soil, seaspray, secondary SO42−, metallurgical emissions and biomass burning release. EPMA also evidenced that one of the most abundant particle types corresponded to marine aerosol, having an average diameter of 0.7 μm for the fine mode and 2.2 μm for the coarse mode aerosol. LAMMA results indicate that, in fact, seaspray has been transported into the city of Santiago de Chile airshed, suffering several transformations and a sulfur enrichment. This analytical technique also provided evidence of the abundance of carbon-rich particles, which were not detected by either the bulk X-ray analysis or EPMA; they are probably due to fossil-fuel combustion releases. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
|
Publication Date |
2003-08-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0957-1272; 1878-2132 |
ISBN |
|
Additional Links |
UA library record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:116456 |
Serial |
7427 |
Permanent link to this record |
|
|
|
Author |
LaBrecque, J.J.; Beusen, J.M.; Van Grieken, R.E. |
Title |
Analysis of lateritic material from Cerro impacto by instrumental neutron activation employing a low-energy photon semiconductor and a high-energy Ge(Li) detector |
Type |
A1 Journal article |
Year |
1986 |
Publication |
Applied spectroscopy |
Abbreviated Journal |
|
Volume |
40 |
Issue ![sorted by Issue field, descending order (down)](img/sort_desc.gif) |
2 |
Pages |
140-144 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Nineteen elements were determined in four different grain size fractions of a bulk geological material from Cerro Impacto for a study of the physical (mechanical) concentration process of different elements based upon the hardness of the different minerals. The analysis was performed by excitation of the sample with a high, slow neutron flux followed by gamma-ray spectroscopy with both a conventional Ge(Li) high-energy detector and a low-energy photon detector (LEPD). The accuracy of this method was studied with the use of two standard reference materials, SY-2 and SY-3, which are similar to the real samples. The values determined were also compared with a secondary target x-ray fluorescence method for all the elements that were suitable to both methods. Actually, the x-ray fluorescence method was found to be more complementary than competitive. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
A1986A085900003 |
Publication Date |
2005-07-21 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0003-7028 |
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:116768 |
Serial |
7448 |
Permanent link to this record |
|
|
|
Author |
Truong, B.; Siegert, K.; Lin, A.; Miller, V.; Krebs, F.C. |
Title |
Apical application of nanosecond-pulsed dielectric barrier discharge plasma causes the basolateral release of adenosine triphosphate as a damage-associated molecular pattern from polarized HaCaT cells |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Plasma medicine |
Abbreviated Journal |
|
Volume |
7 |
Issue ![sorted by Issue field, descending order (down)](img/sort_desc.gif) |
2 |
Pages |
117-131 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Promising biomedical uses for nonthermal plasma (NTP) in the fields of regenerative medicine, cancer therapy, and vaccine delivery involve the noninvasive application of uniform nonequilibrium plasma (including dielectric barrier discharge plasma) to living skin. Whereas most investigations have focused on achieving desired therapeutic outcomes, fewer studies have examined the mechanisms and pathways by which epithelial cells respond to NTP exposure. Using a transwell apical-basolateral-chambered system to culture the human keratinocyte HaCaT cell line, in vitro experiments were performed to demonstrate the effects of nanosecond-pulsed dielectric barrier discharge (nsDBD) plasma on polarized epithelial cell viability, monolayer permeability, intracellular oxidative stress, and the release of adenosine triphosphate (ATP). Application of nsDBD plasma at 60 Hz or below had minimal or no effect on HaCaT monolayer viability or permeability. nsDBD plasma exposure did, however, result in frequency-dependent reductions in intracellular glutathione (indicating direct induction of oxidative stress by nsDBD plasma) and increased extracellular ATP concentrations in the ba-solateral (subepithelial) media, which are indicators of cellular stress and an NTP-induced inflammatory response. These studies provide new insights into nsDBD plasma-induced inflammation and local innate immune responses initiated by polarized epithelial tissues. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
|
Publication Date |
2017-02-24 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
|
ISBN |
|
Additional Links |
UA library record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:155656 |
Serial |
7465 |
Permanent link to this record |
|
|
|
Author |
Idris, A.M.; Eltayeb, M.A.H.; Potgieter-Vermaak, S.S.; Van Grieken, R.; Potgieter, J.H. |
Title |
Assessment of heavy metals pollution in Sudanese harbours along the Red Sea Coast |
Type |
A1 Journal article |
Year |
2007 |
Publication |
Microchemical journal |
Abbreviated Journal |
|
Volume |
87 |
Issue ![sorted by Issue field, descending order (down)](img/sort_desc.gif) |
2 |
Pages |
104-112 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000251750000003 |
Publication Date |
2007-07-05 |
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:66067 |
Serial |
7504 |
Permanent link to this record |
|
|
|
Author |
Buczyńska, A.J.; Krata, A.; Stranger, M.; Godoi, A.F.L.; Kontozova-Deutsch, V.; Bencs, L.; Naveau, I.; Roekens, E.; Van Grieken, R. |
Title |
Atmospheric BTEX-concentrations in an area with intensive street traffic |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Atmospheric environment : an international journal |
Abbreviated Journal |
|
Volume |
43 |
Issue ![sorted by Issue field, descending order (down)](img/sort_desc.gif) |
2 |
Pages |
311-318 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
The major threat to clean air in developed and industrializing countries is now posed by traffic emissions. The effects of traffic road modifications on the air quality are, however, rarely reported in the literature. The aim of this study was to determine the influence of the modernization and renovation of a traffic artery in the region of Mortsel (Antwerp, Belgium) on the concentration of volatile organic compounds such as: benzene, toluene, ethylbenzene and m-, p-, o-xylenes (BTEX). The original goal of the reconstruction works was to reduce the traffic lanes of one of the busiest streets in Antwerp, in order to discourage the road traffic and in consequence also to improve the air quality in this region. The average concentrations of BTEX before these works in 2003 were: 1.6, 7.0, 0.9, 2.3, and 0.9 ìg/m3, for benzene, toluene, ethylbenzene, m + p xylenes, and o-xylene, respectively. However, after the completion of the works, in 2005, they were slightly higher: 2.5, 9.5, 1.6, 3.4, and 1.3 ìg/m3, respectively. The scatter plots of benzene against toluene, ethylbenzene and xylenes in 2003 and 2005 showed very good correlations. This fact indicated that all of the measured compounds originated from the same source, namely the road traffic. Moreover, the data obtained from an air-monitoring station at less than 6 km distance from the sampling site (operated by the Flemish Environment Agency, and located in Borgerhout, Antwerp), confirmed the lack of influence of background concentrations of BTEX. The obtained results led to the conclusion that the reduction of the number of traffic lanes had apparently increased the traffic jams and also increased the emission from cars. Therefore, these modernization works had even a negative impact on the local concentration of traffic-related pollutants as BTEX. |
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000262956500011 |
Publication Date |
2008-10-18 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1352-2310 |
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:72925 |
Serial |
7518 |
Permanent link to this record |
|
|
|
Author |
Van Dyck, P.; Markowicz, A.; Van Grieken, R. |
Title |
Automatic absorption correction in x-ray fluorescence analysis of intermediate thickness samples using a dual external reference signal |
Type |
A1 Journal article |
Year |
1980 |
Publication |
X-ray spectrometry |
Abbreviated Journal |
|
Volume |
9 |
Issue ![sorted by Issue field, descending order (down)](img/sort_desc.gif) |
2 |
Pages |
70-76 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
A method has been investigated which allows calculations from the X-ray fluorescence spectra of the absorption coefficients at any energy for any sample, without any additional measurement. Use is made of the ratio of the characteristic X-ray signals from a Zr wire positioned in front of the sample and from a Pd foil placed behind the sample, both in a fixed geometry. From the experimentally measured absorption coefficient at the Pd L energy (2.9 keV), the coefficients for higher energies are calculated. By the use of an iterative computer routine in which corrections for the enhancement of the Pd foil by the sample are also included, an accuracy of 2% or better on the absorption coefficient determination can be reached for homogenous samples in one measurement. Grain-size and heterogeneity effects induce inaccuracies on the absorption coefficient determinations which might well reach 20% for particulate samples like intermediate thickness deposits of geological materials. This approach thus has the same limitations as the classical transmission method for such heterogeneous samples. |
Address |
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Corporate Author |
|
Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
A1980JN16500007 |
Publication Date |
2005-05-28 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0049-8246 |
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:116483 |
Serial |
7541 |
Permanent link to this record |
|
|
|
Author |
Van Grieken, R. |
Title |
Awards for best referees of X-ray Spectrometry |
Type |
Editorial |
Year |
2014 |
Publication |
X-ray spectrometry |
Abbreviated Journal |
|
Volume |
43 |
Issue ![sorted by Issue field, descending order (down)](img/sort_desc.gif) |
2 |
Pages |
68-69 |
Keywords |
Editorial; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
|
Publication Date |
2014-02-07 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0049-8246 |
ISBN |
|
Additional Links |
UA library record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:114471 |
Serial |
7542 |
Permanent link to this record |
|
|
|
Author |
Annegarn, H.; Van Grieken, R.; van Espen, P.; von Blottnitz, F.; Sellschop, J.; Winchester, J.; Maenhaut, W. |
Title |
Background aerosol composition at Gobabeb, South West Africa |
Type |
A3 Journal article |
Year |
1976 |
Publication |
Madoqua |
Abbreviated Journal |
|
Volume |
|
Issue ![sorted by Issue field, descending order (down)](img/sort_desc.gif) |
2 |
Pages |
107-118 |
Keywords |
A3 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3) |
Abstract |
|
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
|
Publication Date |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1011-5498 |
ISBN |
|
Additional Links |
UA library record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:116512 |
Serial |
7544 |
Permanent link to this record |
|
|
|
Author |
Bencs, L. |
Title |
Calculation of the spectral line profile broadening parameter in graphite furnace atomic absorption spectrometry |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Canadian Journal Of Analytical Sciences And Spectroscopy |
Abbreviated Journal |
|
Volume |
53 |
Issue ![sorted by Issue field, descending order (down)](img/sort_desc.gif) |
2 |
Pages |
52-58 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
A polynomial approach is applied for a number of data from the Posener-tables to calculate the values of the intensity distribution function of atomic absorption lines – H(a, 0.726a) – at the tabulated damping-parameter values with an error not worse than 0.044 %. For the resultant H(a, 0.726a) data, the ninth and sixth order polynomials can be fitted according to the damping parameter range of 0-2, and 2-10, respectively, which results in a minimal error of approximation. The derived functions are simply applicable to the calculation of any H(a, 0.726a) value belonging to a damping-parameter of any arbitrarily selected spectral line, implying the influence of Doppler- and Lorentz-broadening. The overall error of the described method is lower than 0.4 %. |
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000260130600002 |
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ISSN |
1205-6685 |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Open Access |
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no |
Call Number |
UA @ admin @ c:irua:103094 |
Serial |
7571 |
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Author |
Fuoco, T.; Cuartero, M.; Parrilla, M.; García-Guzmán, J.J.; Crespo, G.A.; Finne-Wistrand, A. |
Title |
Capturing the real-time hydrolytic degradation of a library of biomedical polymers by combining traditional assessment and electrochemical sensors |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Biomacromolecules |
Abbreviated Journal |
Biomacromolecules |
Volume |
22 |
Issue ![sorted by Issue field, descending order (down)](img/sort_desc.gif) |
2 |
Pages |
949-960 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
We have developed an innovative methodology to overcome the lack of techniques for real-time assessment of degradable biomedical polymers at physiological conditions. The methodology was established by combining polymer characterization techniques with electrochemical sensors. The in vitro hydrolytic degradation of a series of aliphatic polyesters was evaluated by following the molar mass decrease and the mass loss at different incubation times while tracing pH and l-lactate released into the incubation media with customized miniaturized electrochemical sensors. The combination of different analytical approaches provided new insights into the mechanistic and kinetics aspects of the degradation of these biomedical materials. Although molar mass had to reach threshold values for soluble oligomers to be formed and specimens’ resorption to occur, the pH variation and l-lactate concentration were direct evidence of the resorption of the polymers and indicative of the extent of chain scission. Linear models were found for pH and released l-lactate as a function of mass loss for the l-lactide-based copolymers. The methodology should enable the sequential screening of degradable polymers at physiological conditions and has potential to be used for preclinical material’s evaluation aiming at reducing animal tests. |
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Publication Date |
2021-01-27 |
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ISSN |
1525-7797 |
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Additional Links |
UA library record |
Impact Factor |
5.246 |
Times cited |
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Open Access |
OpenAccess |
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Approved |
Most recent IF: 5.246 |
Call Number |
UA @ admin @ c:irua:175296 |
Serial |
7575 |
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Author |
Serneels, S.; Faber, K.; Verdonck, T.; van Espen, P.J. |
Title |
Case specific prediction intervals for tri-PLS1 : the full local linearisation |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Chemometrics and intelligent laboratory systems |
Abbreviated Journal |
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Volume |
108 |
Issue ![sorted by Issue field, descending order (down)](img/sort_desc.gif) |
2 |
Pages |
93-99 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
A new method to estimate case specific prediction uncertainty for univariate trilinear partial least squares (tri-PLS1) regression is introduced. This method is, from a theoretical point of view, the most exact finite sample approximation to true prediction uncertainty that has been reported up till now. Using the new method, different error sources can be propagated, which is an advantage that cannot be offered by data driven approaches such as the bootstrap. In a concise example, it is illustrated how the method can be applied. In the Appendix, efficient algorithms are presented to compute the estimates required. |
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000295310000002 |
Publication Date |
2011-05-12 |
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ISSN |
0169-7439; 1873-3239 |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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no |
Call Number |
UA @ admin @ c:irua:92788 |
Serial |
7580 |
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Author |
Bencs, L.; Szakács, O.; Szoboszlai, N.; Ajtony, Z.; Bozsai, G. |
Title |
Characteristics of atomic absorption calibration curves with the transversely heated graphite furnace |
Type |
A1 Journal article |
Year |
2003 |
Publication |
Journal of analytical atomic spectrometry |
Abbreviated Journal |
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Volume |
18 |
Issue ![sorted by Issue field, descending order (down)](img/sort_desc.gif) |
2 |
Pages |
105-110 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Calibration curves with two quasi-linear sections ("double sloping'') were observed for the medium volatile elements, Cr and Cu, with the use of a SIMAA 6000 graphite furnace atomic absorption spectrometer under interrupted internal gas flow conditions. If a standard transversally heated graphite atomizer (THGA) tube was shortened by 0.5 mm at both of its ends, (i.e. the gaps were enlarged between graphite furnace housing and tube ends), a stronger declination of the calibration curves resulted. Elements with fairly high diffusion coefficients (>5.8 cm(2) s(-1)) and with short appearance time of their transients (<0.6 s), such as Cr and Cu, have shown the most characteristic sensitivity drop towards higher concentrations. This anomalous feature could be eliminated in three different ways; (1) by applying end-capped THGA tubes, (2) using mini-flow (50 cm(3) min(-1)) conditions during the atomization stage, and (3) by adding Pd-Mg chemical modifier. For the low volatile Mo and V, the calibration curves had no irregular shape. For Ag, Co, Cr, Cu, Mn and Ni, the mini-flow settings improved the linearity of the calibration curves and extended the upper limit of the linear calibration range by a factor of 1.5-2.0. The irregular characteristic of the analytical curves was interpreted as an increased vapour loss at higher analyte concentrations through the opened ends of the standard THGA tubes. This vapour loss was associated with the significantly diverse expulsion velocities of atoms, caused by the difference in temperature and concentration gradients, when evaporating amounts of analytes with more than one order of magnitude difference. |
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000180666600003 |
Publication Date |
2003-01-28 |
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ISSN |
0267-9477 |
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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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no |
Call Number |
UA @ admin @ c:irua:103320 |
Serial |
7606 |
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Author |
Palacios, O.M.; van Meel, K.; Van Grieken, R.; Marcó P., L.-M.; Vázquez, C. |
Title |
Characterization of black volcanites from the Limay river basin, Patagonia, Argentina, using energy dispersive X-ray fluorescence spectrometry : an aid to infer human group mobility |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Journal of radioanalytical and nuclear chemistry |
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Volume |
298 |
Issue ![sorted by Issue field, descending order (down)](img/sort_desc.gif) |
2 |
Pages |
1245-1255 |
Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
The investigation of hunter-gatherers archaeological sites in the Limay river basin, Patagonia, Argentina, raised questions concerning the lithic technology. The chemical characterization of artifacts, rocks and possible sources of provenances could help to elucidate the hunter-gatherer mobility. In three archaeological sitesRincón Chico 2 (RCh2/87; 14C 710 ± 60 BP), Cueva Traful I (CTI; 14C 9430 ± 230 BP) and Casa de Piedra de Ortega (CPO; 14C 2840 ± 80 BP), tools and debitage or discarded flakes made in black volcanic rock have been found. Nearby an extensive rock outcrop of black volcanite, Paso Limay quarry (CPL), with similar characteristics was located. Samples coming from these four sites were analyzed by energy dispersive X-ray fluorescence spectrometry. This characterization allowed the geochemical classification of the lithic material and to correlate the samples with the suspected source after a previous statistical analysis. The majority of the samples were classified as dacites and rhyolites. Only samples coming from CPO site, the closest place to CPL were made exclusively with the quarry rocks. A set of five samples from RCh2/87 and two samples from CTI appear to have same chemical composition as CPL in spite of this site is placed in the opposite bank of the Limay river suggesting that hunter-gatherers could accede to the quarry, eventually. Finally, only a set of five samples coming from RCh2/87 and CTI do not group with the quarry. This fact evidences the existence of secondary sources of supply. The information of this research allowed inferring ancient human mobility patterns in the region. |
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000325624300061 |
Publication Date |
2013-07-25 |
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ISSN |
0236-5731; 1588-2780 |
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UA library record; WoS full record |
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no |
Call Number |
UA @ admin @ c:irua:109743 |
Serial |
7619 |
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Author |
Smits, J.; Van Grieken, R. |
Title |
Chelating 2,2′-diaminodiethylamine cellulose filters and X-ray fluorescence for preconcentration and trace analysis of natural waters |
Type |
A1 Journal article |
Year |
1981 |
Publication |
International journal of environmental analytical chemistry |
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Volume |
9 |
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2 |
Pages |
81-92 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
The 2,2′-diaminodiethylamine (DEN) functional group can be expected to have ideal properties for the chelation of transition metals and their collection from aqueous solutions, independent of the alkali and alkaline earth ions concentration. Introducing DEN into cellulose filters allows straightforward preconcentration of trace cations by a simple filtration step, and the DEN-filter constitutes a suitable target for X-ray fluorescence (XRF) analysis. The linearity between the XRF-response on the loaded DEN-filter and the trace cation concentration in the solution appears excellent, up to a total filter capacity of ca. 3 μeq.cm−2. The detection limits are around 0.5 μg. l−1 in most practical cases. Accuracy and precision are around 10%. The applicability of the proposed procedure is illustrated on a comparative basis by XRF-analysis of drinking water and surface water, after preconcentration by DEN-filtration and by alternative procedures. |
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A1981LF48000001 |
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2007-07-07 |
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0306-7319 |
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UA library record; WoS full record; WoS citing articles |
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Call Number |
UA @ admin @ c:irua:116571 |
Serial |
7638 |
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Author |
Osán, J.; Török, S.; Alföldy, B.; Alsecz, A.; Falkenberg, G.; Baik, S.Y.; Van Grieken, R. |
Title |
Comparison of sediment pollution in the rivers of the Hungarian Upper Tisza Region using non-destructive analytical techniques |
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A1 Journal article |
Year |
2007 |
Publication |
Spectrochimica acta: part B : atomic spectroscopy |
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Volume |
62 |
Issue ![sorted by Issue field, descending order (down)](img/sort_desc.gif) |
2 |
Pages |
123-136 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
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000246087100006 |
Publication Date |
2007-02-23 |
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ISSN |
0584-8547; 1873-3565 |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Call Number |
UA @ admin @ c:irua:63420 |
Serial |
7696 |
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