Institution
University of Johannesburg
Education•Johannesburg, South Africa•
About: University of Johannesburg is a education organization based out in Johannesburg, South Africa. It is known for research contribution in the topics: Population & Tourism. The organization has 8070 authors who have published 22749 publications receiving 329408 citations. The organization is also known as: UJ.
Topics: Population, Tourism, Large Hadron Collider, Adsorption, Higher education
Papers published on a yearly basis
Papers
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TL;DR: In this paper, a review discusses the synthesis and the possible applications of nitrogen-doped carbon nanotubes as supports for metal nanoparticles in heterogeneous catalysis, and discusses the applications of carbon-based supports for noble metal catalysts.
Abstract: The science and technology of catalysis is of fundamental importance to a national economy. Today about 90% of all technical chemicals are manufactured by the use of catalysts. Nanoparticles of noble metals are extremely important materials in the catalysis industry due to cost issues and properties that are not found in their bulk state. An efficient way to produce and stabilise noble metal nanoparticles is by dispersion on a suitable support. Carbon-based supports, such as carbon nanotubes, carbon spheres, carbon fibres, etc., have been found to be good supports for metal nanoparticles. However, to be used effectively, the carbon surface must be modified either by functionalisation or doping. This review discusses the synthesis and the possible applications of nitrogen-doped carbon nanotubes as supports for metal nanoparticles in heterogeneous catalysis.
144 citations
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TL;DR: In this article, a search for pair production of vector-like quarks, both up-type and down-type (B), as well as for four-top-quark production, is presented.
Abstract: A search for pair production of vector-like quarks, both up-type (T) and down-type (B), as well as for four-top-quark production, is presented. The search is based on pp collisions at TeV recorded in 2012 with the ATLAS detector at the CERN Large Hadron Collider and corresponding to an integrated luminosity of 20.3 fb(-1). Data are analysed in the lepton-plus-jets final state, characterised by an isolated electron or muon with high transverse momentum, large missing transverse momentum and multiple jets. Dedicated analyses are performed targeting three cases: a T quark with significant branching ratio to a W boson and a b-quark , and both a T quark and a B quark with significant branching ratio to a Higgs boson and a third-generation quark ( respectively). No significant excess of events above the Standard Model expectation is observed, and 95% CL lower limits are derived on the masses of the vector-like T and B quarks under several branching ratio hypotheses assuming contributions from T -> Wb, Zt, Ht and B -> Wt, Zb, Hb decays. The 95% CL observed lower limits on the T quark mass range between 715 GeV and 950 GeV for all possible values of the branching ratios into the three decay modes, and are the most stringent constraints to date. Additionally, the most restrictive upper bounds on four-top-quark production are set in a number of new physics scenarios.
144 citations
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TL;DR: In this paper, a paleomagnetic pole from the Neo-archean Ventersdorp supergroup of South Africa is reported, which provides quantitative support for Vaalbara's existence.
144 citations
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TL;DR: In this paper, the authors present Fe isotope data for bulk samples from 24 Archean and Proterozoic iron formations and eight Phanerozoic Fe oxide-rich deposits and find that the positive δ 56 Fe values in IF are best explained by delivery of particulate ferric oxides formed in the water column to the sediment-water interface.
144 citations
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TL;DR: A combined search for the Standard Model Higgs boson with the ATLAS detector at the LHC is presented in this article, where the data sets used correspond to integrated luminosities from 4.6 fb (-1) to 4.9 fb(-1) of proton-proton collisions collected at root s = 7 TeV in 2011.
Abstract: A combined search for the Standard Model Higgs boson with the ATLAS detector at the LHC is presented. The data sets used correspond to integrated luminosities from 4.6 fb(-1) to 4.9 fb(-1) of proton-proton collisions collected at root s = 7 TeV in 2011. The Higgs boson mass ranges of 111.4 GeV to 116.6 GeV, 119.4 GeV to 122.1 GeV, and 129.2 GeV to 541 GeV are excluded at the 95% confidence level, while the range 120 GeV to 560 GeV is expected to be excluded in the absence of a signal. An excess of events is observed at Higgs boson mass hypotheses around 126 GeV with a local significance of 2.9 standard deviations (sigma). The global probability for the background to produce an excess at least as significant anywhere in the entire explored Higgs boson mass range of 110-600 GeV is estimated to be similar to 15%, corresponding to a significance of approximately 1 sigma.
143 citations
Authors
Showing all 8414 results
Name | H-index | Papers | Citations |
---|---|---|---|
Vinod Kumar Gupta | 165 | 713 | 83484 |
Arnold B. Bakker | 135 | 506 | 103778 |
Trevor Vickey | 128 | 873 | 76664 |
Ketevi Assamagan | 128 | 934 | 77061 |
Diego Casadei | 123 | 733 | 69665 |
Michael R. Hamblin | 117 | 899 | 59533 |
E. Castaneda-Miranda | 117 | 545 | 56349 |
Xiaoming Li | 113 | 1932 | 72445 |
Katharine Leney | 108 | 459 | 52547 |
M. Aurousseau | 103 | 403 | 44230 |
Mika Sillanpää | 96 | 1019 | 44260 |
Sahal Yacoob | 89 | 408 | 25338 |
Evangelia Demerouti | 85 | 236 | 49228 |
Lehana Thabane | 85 | 994 | 36620 |
Sahal Yacoob | 84 | 399 | 35059 |