Institution
University of Saskatchewan
Education•Saskatoon, Saskatchewan, Canada•
About: University of Saskatchewan is a education organization based out in Saskatoon, Saskatchewan, Canada. It is known for research contribution in the topics: Population & Health care. The organization has 25021 authors who have published 52579 publications receiving 1483049 citations. The organization is also known as: USask.
Papers published on a yearly basis
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TL;DR: These findings explained in part why many clinical cases of immature teeth with apical periodontitis or abscess may gain root thickness and apical length after conservative treatment with the revitalization procedure.
394 citations
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TL;DR: A new type of compact layer free bilayer perovskite solar cell is reported and it is conclusively demonstrated that the ETL is not a prerequisite for obtaining excellent device efficiencies.
Abstract: The recent breakthrough of organometal halide perovskites as the light harvesting layer in photovoltaic devices has led to power conversion efficiencies of over 16%. To date, most perovskite solar cells have adopted a structure in which the perovskite light absorber is placed between carrier-selective electron- and hole-transport layers (ETLs and HTLs). Here we report a new type of compact layer free bilayer perovskite solar cell and conclusively demonstrate that the ETL is not a prerequisite for obtaining excellent device efficiencies. We obtained power conversion efficiencies of up to 11.6% and 13.5% when using poly(3-hexylthiophene) and 2,2′,7,7′-tetrakis(N,N-di(4-methoxyphenyl)amino)-9,9′-spirobifluorene, respectively, as the hole-transport material. This performance is very comparable to that obtained with the use of a ZnO ETL. Impedance spectroscopy suggests that while eliminating the ZnO leads to an increase in contact resistance, this is offset by a substantial decrease in surface recombination.
393 citations
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TL;DR: Exogenous control of luteal and follicular development facilitates the application of assisted reproductive technologies in B. indicus cattle by offering the possibility of planning AI programs without the necessity of oestrus detection and without sacrificing the overall results.
392 citations
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TL;DR: This paper considers the graph of the Delaunay triangulation ofS, DT, and definesθ(S), the fixed-angleθ-graph and shows thatθ (S) ((1/cosθ)(1/(1−tanθ)))-approximates the complete Euclidean graph.
Abstract: LetS be a set ofN points in the Euclidean plane, and letd(p, q) be the Euclidean distance between pointsp andq inS. LetG(S) be a Euclidean graph based onS and letG(p, q) be the length of the shortest path inG(S) betweenp andq. We say a Euclidean graphG(S)t-approximates the complete Euclidean graph if, for everyp, q ?S, G(p, q)/d(p, q) ≤t. In this paper we present two classes of graphs which closely approximate the complete Euclidean graph. We first consider the graph of the Delaunay triangulation ofS, DT(S). We show that DT(S) (2?/(3 cos(?/6)) ? 2.42)-approximates the complete Euclidean graph. Secondly, we define?(S), the fixed-angle?-graph (a type of geometric neighbor graph) and show that?(S) ((1/cos?)(1/(1?tan?)))-approximates the complete Euclidean graph.
391 citations
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TL;DR: In this article, two characteristic Li2O2 morphologies are formed in carbon nanotube (CNT) electrodes in a 1,2-dimethoxyethane (DME) electrolyte: discs/toroids (50-200 nm) at low rates/overpotentials (10 mA gC−1 or E > 2.7 V vs. Li), or small particles (<20 nm), while discs exhibit a sloping profile with low overpotential (<4 V).
Abstract: Understanding the origins of high overpotentials required for Li2O2 oxidation in Li–O2 batteries is critical for developing practical devices with improved round-trip efficiency. While a number of studies have reported different Li2O2 morphologies formed during discharge, the influence of the morphology and structure of Li2O2 on the oxygen evolution reaction (OER) kinetics and pathways is not known. Here, we show that two characteristic Li2O2 morphologies are formed in carbon nanotube (CNT) electrodes in a 1,2-dimethoxyethane (DME) electrolyte: discs/toroids (50–200 nm) at low rates/overpotentials (10 mA gC−1 or E > 2.7 V vs. Li), or small particles (<20 nm) at higher rates/overpotentials. Upon galvanostatic charging, small particles exhibit a sloping profile with low overpotential (<4 V) while discs exhibit a two-stage process involving an initially sloping region followed by a voltage plateau. Potentiostatic intermittent titration technique (PITT) measurements reveal that charging in the sloping region corresponds to solid solution-like delithiation, whereas the voltage plateau (E = 3.4 V vs. Li) corresponds to two-phase oxidation. The marked differences in charging profiles are attributed to differences in surface structure, as supported by X-ray absorption near edge structure (XANES) data showing that oxygen anions on disc surfaces have LiO2-like electronic features while those on the particle surfaces are more bulk Li2O2-like with modified electronic structure compared to commercial Li2O2. Such an integrated structural, chemical, and morphological approach to understanding the OER kinetics provides new insights into the desirable discharge product structure for charging at lower overpotentials.
390 citations
Authors
Showing all 25277 results
Name | H-index | Papers | Citations |
---|---|---|---|
Tomas Hökfelt | 158 | 1033 | 95979 |
Frederick Wolfe | 119 | 417 | 101272 |
Christopher G. Goetz | 116 | 651 | 59510 |
John P. Giesy | 114 | 1162 | 62790 |
Helmut Kettenmann | 104 | 380 | 40211 |
Paul M. O'Byrne | 104 | 605 | 56520 |
Susan S. Taylor | 104 | 518 | 42108 |
Keith A. Hobson | 103 | 653 | 41300 |
Mark S. Tremblay | 100 | 541 | 43843 |
James F. Fries | 100 | 369 | 83589 |
Gordon McKay | 97 | 661 | 61390 |
Jonathan D. Adachi | 96 | 589 | 31641 |
Wenjun Zhang | 96 | 976 | 38530 |
William C. Dement | 96 | 340 | 43014 |
Chris Ryan | 95 | 971 | 34388 |