Browsing Research Articles (University of Pretoria) by Title

Browsing Research Articles (University of Pretoria) by Title

Sort by: Order: Results:

  • Ab initio studies of bimetallic-doped {0001} hematite surface for enhanced photoelectrochemical water splitting 
    Simfukwe, Joseph; Mapasha, Refilwe Edwin; Braun, Artur; Diale, M. (Mmantsae Moche) (MDPI, 2021-08)
    First-principles calculations based on density functional theory (DFT) were carried out to study the energetic stability and electronic properties of a bimetallic-doped α-Fe2O3 photoanode surface with (Zn, Ti) and (Zn, ...
  • Ab initio studies of hydrogen adatoms on bilayer graphene 
    Mapasha, Refilwe Edwin; Ukpong, Aniekan M.; Chetty, Nithaya (American Physical Society, 2012-05)
    We present a comparative density functional study of the adsorption of hydrogen on bilayer graphene. Six different exchange-correlation functionals are employed to explore the possible configurations of hydrogen ad- sorption ...
  • Ab initio studies of isolated boron substitutional defects in graphane 
    Mapasha, Refilwe Edwin; Chetty, Nithaya (IOP Publishing Limited, 2017)
    We have systematically studied energetics, structural and electronic properties of di erent con gurations of the B atoms substituting C-H pairs located on a single hexagonal ring in a graphane system using the rst-principles ...
  • Ab initio studies of isolated hydrogen vacancies in graphane 
    Mapasha, Refilwe Edwin; Molepo, Mahlanga P.; Chetty, Nithaya (Elsevier, 2016-05)
    We present a density functional study of various hydrogen vacancies located on a single hexagonal ring of graphane (fully hydrogenated graphene) considering the e ects of charge states and the position of the Fermi level. ...
  • Ab initio studies of staggered Li adatoms on graphene 
    Mapasha, Refilwe Edwin; Chetty, Nithaya (Elsevier, 2010-06)
    We study Li on graphene using the Vienna ab initio Simulation Package employing the projector-augmented wave method within the generalized gradient approximation for the exchange-correlation potential. We give detailed ...
  • Ab initio study of aluminium impurity and interstitial-substitutional complexes in Ge using a hybrid functional (HSE) 
    Igumbor, Emmanuel; Mapasha, Refilwe Edwin; Meyer, Walter Ernst (Springer, 2017-07)
    The results of an ab initio modelling of aluminium substitutional impurity (AlGe), aluminium interstitial in Ge [IAl for the tetrahedral (T) and hexagonal (H) configurations] and aluminium interstitial-substitutional ...
  • Ab initio study of metastability of Eu3+ defect complexes in GaN 
    Ouma, C.N.M.; Meyer, Walter Ernst (Elsevier, 2014-04)
    Density functional theory (DFT) within the generalized gradient approximation (GGA) has been used to study the structural and electronic properties of Eu3þ defect complexes in GaN under Ga-rich conditions. Two distinct ...
  • Ab initio study of the effect of hydrogen passivation on boron-oxygen-carbon related defect complexes in silicon 
    Abdurrazaq, Abdulgaffar; Raji, Abdulrafiu T.; Meyer, Walter Ernst (Elsevier, 2020-05)
    Please read abstract in the article.
  • Ab Initio study of MgTe self-interstitial (Mgi and Tei) : a wide band gap semiconductor 
    Igumbor, Emmanuel; Omotoso, Ezekiel; Meyer, Walter Ernst (Trans Tech Publications, 2017-06)
    We present results of defect formation energies and charge state thermodynamic transition levels of Mg and Te interstitials in MgTe wurzite structure. We use the generalized gradient approximation and local density ...
  • Ab-initio study of germanium di-interstitial using a hybrid functional (HSE) 
    Igumbor, Emmanuel; Ouma, C.N.M.; Webb, Geoffrey; Meyer, Walter Ernst (Elsevier, 2016-01)
    In this work, we present ab-initio calculation results of Ge di-interstitials (I2(Ge)) in the framework of the density functional theory (DFT) using the Heyd, Scuseria, and Ernzerhof (HSE) hybrid functional. The formation ...
  • Ab-initio study of MgSe self-interstitial (Mgi and Sei) 
    Igumbor, Emmanuel; Obodo, Kingsley Onyebuchi; Meyer, Walter Ernst (Trans Tech Publications, 2016)
    We present detailed calculations of formation and thermodynamics transition state energies of Mgi and Sei interstitial defects in MgSe using generalized gradient approximation (GGA) and local density approximation (LDA) ...
  • An ab-initio study of P-type ZrCoY (Y[dbnd]Sb and Bi) half – Heusler semiconductors 
    Allan, Lynet; Mulwa, Winfred M.; Mwabora, Julius M.; Musembi, Robinson J.; Mapasha, Refilwe Edwin (Elsevier, 2023-08)
    Please read abstract in article.
  • Ab-initio study of the optical properties of beryllium-sulphur co-doped graphene 
    Olaniyan, Okikiola; Igumbor, Emmanuel; Khaleed, Abubakar A.; Mirghni, Abdulmajid Abdallah; Manyala, Ncholu I. (American Institute of Physics, 2019)
    Graphene is a carbon material with excellent properties, which makes it applicable in a myriad of applications. However, the range of the applications of graphene can be extended to the developing field of nanoelectronics ...
  • Abaxial tail implantation in the emu, Dromaius navaehollandiae : morphological characteristics and origin of a rare avian sperm defect 
    Du Plessis, Lizette; Soley, John Thomson (Elsevier, 2012-04)
    Abaxial tail implantation is a defect occurring in the neck region of spermatozoa and is characterized by misalignment of the centriolar complex relative to the head base. This defect has been described in a number of ...
  • The ABC of haemorrhagic shock in the pregnant woman 
    De Kock, J.; Heyns, Tanya; Van Rensburg, Gisela H. (Medpharm Publications, 2008)
    Haemorrhagic shock is more common in the pregnant woman than generally acknowledged in the clinical setting. In most cases antepartum and postpartum haemorrhage can be managed effectively by concentrating on the management ...
  • The ABCs of an NRF rating 
    Wingfield, Brenda D. (AOSIS Open Journals, 2014)
    I have now been awarded virtually every NRF (National Research Foundation) rating reasonably available. Many years ago at the start of my academic life I received a 'Y' label; I have recently been awarded an 'A' rating. ...
  • Abdication of responsibility or justifiable fear of Illegitimacy? The death penalty, gay rights, and the role of public opinion in judicial determinations in Africa 
    Abebe, Adem Kassie (The American Society of Comparative Law, 2012)
    This Article analyzes the extent to which some of the highest courts in Africa have tackled the potential conflict between the power of judicial review on the one hand, and public opinion on the other, by looking at two ...
  • Abelian Cayley graphs of given degree and diameter 2 and 3 
    Vetrik, Tomas (Springer, 2014-11)
    Please read abstract in the article.
  • Aberrant extradural spinal migration of Spirocerca lupi : four dogs 
    Du Plessis, C.J.; Keller, Ninette; Millward, Ian Ralph (Blackwell, 2007-05)
    Spirocerca lupi is a nematode mainly affecting dogs but has been found in other animals, particularly carnivores. Anatomical areas of typical and aberrant migration vary. This report describes four cases of Spirocerca lupi ...
  • Aberrant function of the C-terminal tail of HIST1H1E accelerates cellular senescence and causes premature aging 
    Flex, Elisabetta; Martinelli, Simone; Van Dijck, Anke; Ciolfi, Andrea; Cecchetti, Serena; Coluzzi, Elisa; Pannone, Luca; Andreoli, Cristina; Radio, Francesca Clementina; Pizzi, Simone; Carpentieri, Giovanna; Bruselles, Allessandro; Catanzaro, Giuseppina; Pedace, Lucia; Miele, Evelina; Carcarino, Elena; Ge, Xiaoyan; Chijiwa, Chieko; Lewis, M.E. Suzanne; Meuwissen, Marije; Kenis, Sandra; Van der Aa, Nathalie; Larson, Austin; Brown, Kathleen; Wasserstein, Melissa P.; Skotko, Brian G.; Begtrup, Amber; Person, Richard; Karayiorgou, Maria; Roos, J.L. (Johannes Louw); Van Gassen, Koen L.; Koopmans, Marije; Bijlsma, Emilia K.; Santen, Gijs W.E.; Barge-Schaapveld, Daniela Q.C.M.; Ruivenkamp, Claudia A.L.; Hoffer, Mariette J.V.; Lalani, Seema R.; Streff, Haley; Craigen, William J.; Graham, Brett H.; Van den Elzen, Annette P.M.; Kamphuis, Daan J.; Ounap, Katrin; Reinson, Karit; Pajusalu, Sander; Wojcik, Monica H.; Viberti, Clara; Di Gaetano, Cornelia; Bertini, Enrico; Petrucci, Simona; De Luca, Alessandro; Rota, Rossella; Ferretti, Elisabetta; Matullo, Giuseppe; Dallapiccola, Bruno; Sgura, Antonella; Walkiewicz, Magdalena; Kooy, R. Frank; Tartaglia, Marco (Elsevier, 2019-09)
    Histones mediate dynamic packaging of nuclear DNA in chromatin, a process that is precisely controlled to guarantee efficient compaction of the genome and proper chromosomal segregation during cell division and to accomplish ...