Author:Thwala, Melusi; Musee, N; Sikhwivhilu, L; Wepener, VDate:Aug 2013The toxicity effects of silver (nAg) and zinc oxide (nZnO) engineered nanoparticles (ENPs) on the duckweed Spirodela punctuta were studied to investigate the potential risks posed by these ENPs towards higher aquatic plants. The influence of ...Read more
Author:Sevenster, PGDate:1951The primary objective of the present investigation was to ascertain the oxygen absorption characteristics of South African coals using a technique based on that developed by Winmill.Read more
Author:Tshilombo, KG; Pistorius, PCDate:2007The authors argue the possibility of using an oxygen probe to follow iron removal during converting, if local equilibrium is established between iron in the matte and the iron oxides in the fayalitic slag. The oxygen activity is expected to ...Read more
Author:Waterhouse, JS; Switsur, VR; Barker, AC; Carter, AHC; Robertson, IDate:30 Jul 2002Annual oxygen and hydrogen isotope ratios in the alpha-cellulose of the latewood of oak (Quercus robur L.) growing on well-drained ground in Norfolk, UK have been measured. The authors have compared the observed values of isotope ratios with ...Read more
Author:Heyes, AMDate:Apr 2001Examination of a failed roof tube from a bagasse boiler showed transverse through-cracks and extensive pitting. The pitting was typically oxygen induced pitting and numerous fatigue cracks had started within these pits. It is highly probable ...Read more
Author:Matseke, Mphoma SDate:Oct 2019The main aim of this work was to synthesize carbon supported CoFe(sub2-x) Ni(subx)o(sub4) nanoparticles with high catalytic activity for ORR in alkaline mediaRead more
Author:Zheng, Haitao; Rohwer, Mark B; Mathe, Mahlanyane KDate:31 Aug 2010Alloyed electrocatalysts such as PtNi/C[1-2], PtCo/C[3], PtCr/C[4], PtFe/C [5-6], and non-alloyed Pt-TiO2/C were reportedly investigated for methanol tolerance during Oxygen reduction reaction (ORR). The high methanol tolerance of these ...Read more
Author:Masa, J; Ozoemena, K; Schuhmann, W; Zagal, JHDate:Aug 2012In this review, we describe and discuss the developments in the use of metalloporphyrins and metallophthalocyanines as catalysts for oxygen reduction in aqueous electrolytes. The main goal of most researchers in this field has been to design ...Read more
Author:Andrew, JE; Johakimu, Jonas K; Ngema, NEDate:Aug 2013Ozone use in conjunction with chlorine dioxide during pulp bleaching offers several advantages over conventional bleaching sequences that make use of chlorine dioxide only. Despite this, in South Africa, only one mill uses ozone. The current ...Read more
Author:Zunckel, M; Emberson, LD; Sowden, MDate:Jun 2006The Cross Border Impact Assessment Project (CAPIA) was designed to develop an understanding of regional surface ozone concentrations and their potential risk to agriculture in southern Africa. Surface ozone concentrations were estimated using ...Read more
Author:Akpakwu, GA; Hancke, GP; Silva, BJ; Abu-Mahfouz, Adnan MIDate:Jul 2016The concept of data distribution within cluster of sensor nodes to the source sink has resulted to intense research in Wireless Sensor Networks (WSNs). In this paper, in order to determine the scheduling length of packet distribution, a ...Read more
Author:Freiboth, H; Goedhals-Gerber, LL; van Dyk, E; Dodd, MDate:Oct 2014A large amount of fruit and money is lost every season due to breaks in the South African fruit export cold chain. With food security becoming an ever growing concern, especially in developing countries like South Africa, a high percentage ...Read more
Author:Gerrand, Jonathan D; Williams, Quentin R; Lunga, D; Pantanowitz, A; Madhi, S; Mahomed, NDate:Jul 2017Within developing countries, there is a realistic need for technologies that can assist medical practitioners in meeting the increasing demand for patient screening and monitoring. To this end, computer aided diagnosis (CAD) based approaches ...Read more
Author:Vogt, T; Pieters, R; Newman, Brent KDate:Apr 2018Polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) were analysed from sediment samples collected in 2012 from rivers, surface runoff canals and estuaries in three highly urbanised ...Read more
Author:Forbes, A; Du Preez, NC; Belyi, VN; Botha, LRDate:Aug 2009In this paper the researchers present results on improved paint stripping performance with an intra-cavity generated Flattened Gaussian Beam (FGB). A resonator with suitable diffractive optical elements was designed in order to produce a ...Read more
Author:Modibedi, Remegia M; Ozoemena, KI; Mathe, Mahlanyane KDate:2013Direct alcohol alkaline fuel cells (DAAFCs) are potential power sources for a variety of portable applications as they provide unique advantages over hydrogen-based fuel cell devices. Alcohols (such as methanol, ethanol, ethylene glycol, and ...Read more
Author:Zeevaart, JG; Parkinson, CJ; De Koning, CBDate:24 May 2004The coupling reaction between ethyl acetoacetate and a number of aryl halides in the presence of palladium acetate, a bulky and electron rich phosphine and K3PO4 is described. The arylated acetoacetate ester is de-acylated under the reaction ...Read more
Author:Zeevaart, JG; Parkinson, CJ; De Koning, CBDate:07 Mar 2005Alpha-Arylation of inethanesulfonamides using palladium catalysis is described. For example, treatment of N-benzyl-Nmethylmethanesulfonamide with catalytic Pd (OAc) (2) in the presence of sodium tert-butoxide, triphenylphosphine and toluene ...Read more
Author:Henriques, R; Griffiths, C; Rego, EH; Mhlanga, MusaDate:May 2011Live-cell fluorescence light microscopy has emerged as an important tool in the study of cellular biology. The development of fluorescent markers in parallel with super-resolution imaging systems has pushed light microscopy into the realm of ...Read more