Vaal University of Technology is a tertiary institution in South Africa. It attracts students from all over the country. It is one of the largest residential Universities of Technology, with about 15,000 students, 300 programs, all primarily taught in English. The campus and facilities are conducive to learning, research, recreation and sport, art and culture, and community service. The campuses have lecture halls, laboratories, a number of auditoriums and office space situated on 46 000 square metres. Four Satellite campuses extend the services of the University, at Secunda, Kempton Park, Klerksdorp and Upington. Besides the four faculties, various departments serve its students, catering for their needs. Wikipedia.
News Article | October 25, 2016
All eyes on Mars Planetary scientists are expecting the first successful landing of a European spacecraft on Mars. As Nature went to press, the Schiaparelli lander — part of the ExoMars joint mission with the Russian Space Agency, Roscosmos — was expected to touch down on the red planet on 19 October. The craft, which launched from Kazakhstan in March on a Russian rocket and separated from its mothership on 16 October, is intended to demonstrate landing technology, but it will also study dust storms that are expected to rage on Mars. The mission’s second component, an orbiter, will begin orbiting Mars on the same day and will analyse the composition of the planet’s thin atmosphere next year. See go.nature.com/2eduxjh for more. Protests at South African universities Student protests over tuition fees continue to disrupt teaching and academic life at South African universities. Violent clashes between students and police have been raging on campuses for several weeks despite calls from university officials to save the academic year from breakdown. Last week, protesters threw petrol bombs at buildings in the University of KwaZulu-Natal in Durban, where a library was torched last month. At the University of Cape Town, teaching resumed on 17 October. But other campuses, including the University of the Western Cape and the Cape Peninsula University of Technology, both in Cape Town, remain closed (pictured is Vaal University of Technology near Johannesburg). Green millions The Green Climate Fund, the United Nations’ financial mechanism for helping developing countries to deal with climate change, approved US$745 million in funding proposals on 14 October. The money will go towards 10 new projects involving 27 nations. The Fund, which six years after it was launched has not yet disbursed any money, has now earmarked a total of $1.17 billion for developing countries. At its meeting in Songdo, South Korea, the Fund’s governing board also selected Howard Bamsey, former director-general of the Global Green Growth Institute and Australia’s special envoy on climate change, as new executive director. Bamsey will replace Héla Cheikhrouhou, who has taken over as Tunisia’s minister for energy, mining and renewables. Big climate win Almost 200 nations have agreed to substantially curb their emissions of chemicals used in refrigeration and air conditioning that act as potent greenhouse gases in the atmosphere. An expansion of the Montreal Protocol, signed on 15 October at a United Nations meeting in Kigali, Rwanda, aims to reduce projected emissions of hydrofluorocarbons (HFCs) by almost 90% over the course of the twenty-first century. The protocol was created in 1987 to halt the destruction of Earth’s protective ozone layer. If left unchecked, heat-trapping HFCs, which have since replaced ozone-depleting chemicals, might have contributed up to 0.5 °C of warming by the end of the century (see go.nature.com/2doehrn). Moonshot report The US Cancer Moonshot Task Force released a report on 17 October detailing its accomplishments and goals. The task force, which is led by US Vice President Joseph Biden, continued its call for data sharing, increased clinical trial participation and molecular tumour profiling. The moonshot aims to double the pace of cancer research. Obama’s Mars plan US President Barack Obama reiterated his goals to send NASA astronauts to Mars in the 2030s. In an 11 October op-ed piece for CNN and at a conference in Pittsburgh, Pennsylvania, Obama said the space agency would work with private companies to develop deep-space habitats for astronauts. This includes asking companies for ideas about attaching privately built modules for living and working to the International Space Station. But with Obama leaving office in three months, the direction of NASA is up to the next president and Congress, so the goals remain uncertain at best. Comet hunter dies Klim Churyumov, co-discoverer of the rubber-duck-shaped comet studied by the European Space Agency’s Rosetta mission, has died aged 79. Working with fellow astronomer Svetlana Gerasimenko, the Ukrainian spotted the comet using a Maksutov telescope in 1969. The space agency selected the body, known as 67P/Churyumov–Gerasimenko, as Rosetta’s target in 2003, and Churyumov followed the mission closely. He lived to see its finale, a crash-landing of the mothership on the comet on 30 September. As well as being an accomplished astronomer who co-discovered a second comet in 1986, Churyumov was an avid popularizer of science and published a series of poetry books for children. Next UN chief Former prime minister of Portugal António Guterres (pictured, left) will be the next secretary-general of the United Nations, taking the helm after Ban Ki-moon (pictured, right) steps down on 31 December. He was appointed by the General Assembly in New York City on 13 October. Guterres, 67, studied engineering and physics in Lisbon, and had a brief career in academia before going into politics. He was high commissioner of the UN’s refugee agency for ten years until 2015, and said that alleviating the suffering of vulnerable people, and gender equality, would be key priorities for his five-year tenure as secretary-general. Galaxy glut With the help of tens of thousands of citizen scientists from around the world, astronomers on 12 October released two data sets on the shapes of some 168,000 galaxies. The catalogues are part of the Galaxy Zoo project, which began in 2007 and has enlisted volunteers to classify nearly 1 million galaxies from the Sloan Digital Sky Survey. The latest projects (described in two papers at https://arxiv.org/abs/1610.03070; 2016 and https://arxiv.org/abs/1610.03068; 2016) include galaxies that are farther away, with images from the Hubble Space Telescope that show galaxies up to 3.6 billion parsecs (12 billion light years) away. The results could help astrophysicists understand how galaxies have evolved. AI manifesto Artificial intelligence (AI) and machine learning hold significant potential for innovation and economic growth, a White House report published on 12 October concludes. Calling for government and private sector investment in research and development, the report says that regulations and standards must keep pace with the conceivable benefits of using AI technology in finance, health care, aviation and self-driving cars. Impacts on the economy and workforce must be scrutinized because automation in industry might particularly affect low-wage jobs, the report argues. Weighing neutrinos The Karlsruhe Tritium Neutrino (KATRIN) experiment in Germany, which is designed to establish the elusive mass of neutrino particles, was switched on for the first time on 14 October. Neutrinos are known to have non-zero masses, but the actual values of those masses have been difficult to measure. KATRIN will weigh the extremely light particles indirectly by measuring the energies of electrons shooting out from the nuclear decay of tritium, an isotope of hydrogen. Researchers have now started beaming electrons inside the 70-metre-long, €60-million (US$66-million) machine, and plan to begin the tritium experiment — expected to last five years — in late 2017. Bob Dylan, who on 13 October became a Nobel laureate in literature, might be scientists’ favourite musician. A 2015 analysis found that Dylan’s song names were mentioned in at least 213 article titles (C. Gornitzki, A. Larsson and B. Fadeel Br. Med. J. 351, h6505; 2015); numerous fields were found to be “a-changin’”. The authors concluded that Dylan’s respect for the medical profession — as evidenced by his lyric “I wish I’d have been a doctor” — is reciprocated. 24–26 October Bill Gates and Richard Branson join 1,000 scientists from around the world for the Grand Challenges conference in London to share ideas on topics from crop research to menstrual hygiene. go.nature.com/2e75xb3 2–4 November The Africa Renewable Energy Forum meets in Marrakesh, Morocco, ahead of the COP22 climate meeting. africa-renewable-energy-forum.com
Ofomaja A.E.,Vaal University of Technology
Industrial Crops and Products | Year: 2011
Kinetic models alone are usually applied to describe adsorption onto porous materials, but little attention is given to the fact that diffusion of pollutants especially large organic pollutant molecules may also control the reaction rates. In this investigation, the kinetics and pseudo-isotherm studies of an organic pollutant, 4-nitrophenol from aqueous solution on mansonia sawdust was examined. The intraparticle diffusion particle plots revealed three distinct sections representing sorption into external diffusion, intraparticle diffusion and diffusion to a biosorption site within the particles. The fractional removal of pollutant versus square root of time plots further revealed three sectional straight lines whose slope may represent the rates of pollutant sorption into macro-, meso- and micropores. The equilibrium capacities determined using four forms of the Ho's pseudo-second order model and the Type-1 pseudo second-order expression was also used to evaluate equilibrium concentrations and pseudo-isotherms were obtained by changing initial concentration, C0. © 2010 Elsevier B.V.
Tengen T.B.,Vaal University of Technology
Nanoscale Research Letters | Year: 2011
Grain shapes are acknowledged to impact nanomaterials' overall properties. Research works on this issue include grain-elongation and grain-strain measurements and their impacts on nanomaterials' mechanical properties. This paper proposes a stochastic model for grain strain undergoing severe plastic deformation. Most models deal with equivalent radii assuming that nanomaterials' grains are spherical. These models neglect true grain shapes. This paper also proposes a theoretical approach of extending existing models by considering grain shape distribution during stochastic design and modelling of nanomaterials' constituent structures and mechanical properties. This is achieved by introducing grain 'form'. Example 'forms' for 2-D and 3-D grains are proposed. From the definitions of form, strain and Hall-Petch-Relationship to Reversed-Hall-Petch-Relationship, data obtained for nanomaterials' grain size and conventional materials' properties are sufficient for analysis. Proposed extended models are solved simultaneously and tested with grain growth data. It is shown that the nature of form evolution depends on form choice and dimensional space. Long-run results reveal that grain boundary migration process causes grains to become spherical, grain rotation coalescence makes them deviate away from becoming spherical and they initially deviate away from becoming spherical before converging into spherical ones due to the TOTAL process. Percentage deviations from spherical grains depend on dimensional space and form: 0% minimum and 100% maximum deviations were observed. It is shown that the plots for grain shape functions lie above the spherical (control) value of 1 in 2-D grains for all considered grain growth mechanisms. Some plots lie above the spherical value, and others approach the spherical value before deviating below it when dealing with 3-D grains. The physical interpretations of these variations are explained from elementary principles about the different grain growth mechanisms. It is observed that materials whose grains deviate further away from the spherical ones have more enhanced properties, while materials with spherical grains have lesser properties. It is observed that there exist critical states beyond which Hall-Petch Relationship changes to Reversed Hall-Petch Relationship. It can be concluded that if grain shapes in nanomaterials are constrained in the way they evolve, then nanomaterials with desired properties can be designed. © 2011 Tengen; licensee Springer.
Ofomaja A.E.,Vaal University of Technology
Bioresource Technology | Year: 2010
The overall biosorption rate of lead(II) onto mansonia wood sawdust has been determined. Kinetic modeling revealed that pseudo-second-order kinetics described the experimental data fully while pseudo-first kinetics followed for only 5 min. Ion-exchange constant, S, was similar to the pseudo-first-order rate constant, k1, indicating that ion-exchange is important only in the first 5 min. Intraparticle diffusion increased with lead(II) concentration while film and pore diffusion decreased. The initial biosorption factor, Ri, showed that initial biosorption was intermediate. Addition of calcium ions reduced initial biosorption almost completely, reduced the amounts of lead(II) removed and increased ion-exchange phenomenon indicating significance of ion-exchange. Increase in temperature was found to increase intraparticle diffusion rate and reduce film and pore diffusion. Activation energy of film diffusion and pseudo-second-order kinetics were highest indicating that film diffusion-controlled the overall rate with active participation of ion-exchange from pseudo-second-order model. © 2010 Elsevier Ltd. All rights reserved.
Osifo P.O.,Vaal University of Technology |
Masala A.,Vaal University of Technology
Journal of Power Sources | Year: 2010
Chitosan (Chs) flakes were prepared from chitin materials that were extracted from the exoskeleton of Cape rock lobsters in South Africa. The Chs flakes were prepared into membranes and the Chs membranes were modified by cross-linking with H2SO4. The cross-linked Chs membranes were characterized for the application in direct methanol fuel cells. The Chs membrane characteristics such as water uptake, thermal stability, proton resistance and methanol permeability were compared to that of high performance conventional Nafion 117 membranes. Under the temperature range studied 20-60 °C, the membrane water uptake for Chs was found to be higher than that of Nafion. Thermal analysis revealed that Chs membranes could withstand temperature as high as 230 °C whereas Nafion 117 membranes were stable to 320 °C under nitrogen. Nafion 117 membranes were found to exhibit high proton resistance of 284 s cm-1 than Chs membranes of 204 s cm-1. The proton fluxes across the membranes were 2.73 mol cm-2 s-1 for Chs- and 1.12 mol cm-2 s-1 Nafion membranes. Methanol (MeOH) permeability through Chs membrane was less, 1.4 × 10-6 cm2 s-1 for Chs membranes and 3.9 × 10-6 cm2 s-1 for Nafion 117 membranes at 20 °C. Chs and Nafion membranes were fabricated into membrane electrode assemblies (MAE) and their performances measure in a free-breathing commercial single cell DMFC. The Nafion membranes showed a better performance as the power density determined for Nafion membranes of 0.0075 W cm-2 was 2.7 times higher than in the case of Chs MEA. © 2010 Elsevier B.V. All rights reserved.
Dikio E.D.,Vaal University of Technology
International Journal of Electrochemical Science | Year: 2011
Diesel oil used as fuel in motor engines has been used as a precursor for the production of carbon nanomaterial without a catalyst precursor. Nanomaterials formed in the process were analysed by High resolution transmission electron microscope, (HR-TEM), Raman spectroscopy, scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), thermogravimetric analysis (TGA) and X-ray diffraction (XRD). Carbon nanomaterial produced from diesel soot show the morphology of carbon nanospheres mixed with carbon nanotubes. The results obtained are presented. © 2011 by ESG.
Shaw I.,Vaal University of Technology
Lung | Year: 2011
This study investigated the effect of 8 weeks, three times weekly, of aerobic exercise (AE), diaphragmatic inspiratory resistive breathing (DR), and aerobic exercise combined with diaphragmatic inspiratory resistive breathing (CE) on pulmonary function and abdominal and thoracic dimensions and kinematics in asthmatics. Eighty-eight inactive, moderate-persistent asthmatics were matched and randomly assigned to AE, DR, CE, or nonexercise control (NE) groups (n = 22 each). AE subjects walked and/or jogged at 60% of age-predicted maximum heart rate. DR subjects performed diaphragmatic breathing combined with inspiratory resistive breathing at varying inspiration, expiration ratios. CE subjects utilized a combination of the AE and DR programs. AE, DR, and CE significantly (p ≤ 0.05) improved chest dimensions and kinematics during inspiration at the height of the second intercostal space, during inspiration and expiration at the height of the xiphoid process, and during inspiration and expiration at the height of the midpoint between the xiphoid process and umbilicus. All exercise interventions significantly improved FVC, FEV 1, PEF, and IVC, while MVV improved following AE and CE. However, CE proved superior to AE at improving FVC (p = 0.001), FEV1 (p = 0.001), and IVC (p = 0.009). There were no significant changes (p > 0.05) in any of the measured parameters in the NE group. CE produces adaptations greater than those for single-mode training in moderate-persistent asthmatics. The results suggest synergy rather than interference between aerobic exercise and diaphragmatic inspiratory resistive breathing and that this mode of training might be useful as an adjunct therapy in asthmatic patients. © 2011 Springer Science+Business Media, LLC.
Pitso T.,Vaal University of Technology
International Journal of Engineering Education | Year: 2013
This article describes the TRIZ-based Creativity model whose prototype was iteratively tested for efficacy in closing the transactional space between undergraduate classroom activities and industrial processes with the purpose of advancing undergraduates' creativity and innovation. The testing of this creativity model included presentations in two conferences of the International Multi-Conference on Engineering and Technological Innovation (IMETI) organised under the auspices of the International Institute of Informatics and Systematics (IIIS) and received excellent reviews (an average of 85%). The effectiveness of this creativity model in developing students' creative abilities was also tested on twenty-four, final-year Process Instrumentation undergraduates after two iterative pilot studies. The pre- and post-test results derived from evaluating students' creative abilities through the standardised Torrance's Tests of Creative Thinking (TTCT) show significance as measured through the t-test. Given the establishment of statistical significance in this study, it can reasonably be inferred that the TRIZ-based Creativity model with its leveraging of the university-industry nexus had a positive effect on increasing undergraduates' creative abilities and sets conducive conditions for students' innovativeness. The design and testing of this creativity model needs to be understood within the framework of the emerging synergistic connection among universities, industry and government which seeks to drive greater innovation and technological advancements for which the university-industry nexus was accentuated in this study. © 2013 TEMPUS Publications.
Swart A.J.,Vaal University of Technology
IEEE Transactions on Education | Year: 2010
Questions are used to obtain information, stimulate thinking, and redirect reasoning. Academics in higher education use questions on a daily basis to stimulate thinking and reasoning in students. Final examination papers are used by academics to assess the retention and application skills of students. The assumption, however, exists that questions relating to application skills at universities of technology should start to dominate the higher academic levels in education, with a subsequent drop in questions regarding retention skills. These questions may be categorized as either higher order or lower order questions. This article attempts to distinguish between these two types of questions in light of Bloom's taxonomy, with similar concepts such as deep and surface learning being examined. The literature review is applied to an electrical engineering module titled Electronics, which serves as the case study. The results of this study indicate that a high percentage of the final examination papers dealt with the objective Application, where students had to make use of numerous mathematical equations to solve various unknowns. The results also indicated that academics in electronics are using more lower order than higher order questions in their final examination papers. A balance is suggested between these two types of questions for various academic levels at universities of technology. © 2009 IEEE.
Enweremadu C.C.,Vaal University of Technology |
Rutto H.L.,Vaal University of Technology
Renewable and Sustainable Energy Reviews | Year: 2010
As the environment degrades at an alarming rate, there have been steady calls by most governments following international energy policies for the use of biofuels. One of the biofuels whose use is rapidly expanding is biodiesel. One of the economical sources for biodiesel production which doubles in the reduction of liquid waste and the subsequent burden of sewage treatment is used cooking oil (UCO). However, the products formed during frying, such as free fatty acid and some polymerized triglycerides, can affect the transesterification reaction and the biodiesel properties. This paper attempts to collect and analyze published works mainly in scientific journals about the engine performance, combustion and emissions characteristics of UCO biodiesel on diesel engine. Overall, the engine performance of the UCO biodiesel and its blends was only marginally poorer compared to diesel. From the standpoint of emissions, NOx emissions were slightly higher while un-burnt hydrocarbon (UBHC) emissions were lower for UCO biodiesel when compares to diesel fuel. There were no noticeable differences between UCO biodiesel and fresh oil biodiesel as their engine performances, combustion and emissions characteristics bear a close resemblance. This is probably more closely related to the oxygenated nature of biodiesel which is almost constant for every biodiesel (biodiesel has some level of oxygen bound to its chemical structure) and also to its higher viscosity and lower calorific value, which have a major bearing on spray formation and initial combustion. © 2010 Elsevier Ltd. All rights reserved.