This page has only limited features, please log in for full access.
Acid mine drainage (AMD), red mud (RM) and coal fly ash (CFA) are potential high environmental pollution problems due to their acidity, toxic metals and sulphate contents. Treatment of acidic mine water requires the generation of enough alkalinity to neutralize the excess acidity. Therefore, red mud types from Germany and Greece were chosen for the neutralization of AMD from South Africa, where this problem is notorious. Because of the high alkalinity, German red mud is the most promising precipitation agent achieving the highest pH-values. CFA is less efficient for a neutralization and precipitation process. An increase in temperature increases the adsorption kinetics. The maximum pH-value of 6.0 can be reached by the addition of 100 g German red mud at 20 °C to AMD-water with an initial pH value of 1.9. German red mud removes 99% of the aluminium as aluminium hydroxide at pH 5.0. The rare earth elements (yttrium and cerium) are adsorbed by Greek red mud with an efficiency of 50% and 80% at 60 °C in 5 min, respectively.
Viktoria Keller; Srecko Stopic; Buhle Xakalashe; Yiqian Ma; Sehliselo Ndlovu; Brian Mwewa; Geoffrey Simate; Bernd Friedrich. Effectiveness of Fly Ash and Red Mud as Strategies for Sustainable Acid Mine Drainage Management. Minerals 2020, 10, 707 .
AMA StyleViktoria Keller, Srecko Stopic, Buhle Xakalashe, Yiqian Ma, Sehliselo Ndlovu, Brian Mwewa, Geoffrey Simate, Bernd Friedrich. Effectiveness of Fly Ash and Red Mud as Strategies for Sustainable Acid Mine Drainage Management. Minerals. 2020; 10 (8):707.
Chicago/Turabian StyleViktoria Keller; Srecko Stopic; Buhle Xakalashe; Yiqian Ma; Sehliselo Ndlovu; Brian Mwewa; Geoffrey Simate; Bernd Friedrich. 2020. "Effectiveness of Fly Ash and Red Mud as Strategies for Sustainable Acid Mine Drainage Management." Minerals 10, no. 8: 707.
This paper critically discusses the structure, properties and applications of ironmaking and steelmaking slags and their silicate-based variants as low-cost adsorbents for removing cations and anions from industrial effluents and wastewater. Undoubtedly, the performance of slag-based adsorbents depends on their physical, chemical and phase chemical properties. The presence of crystalline phases, for example, has a significant effect on the adsorption capacity. However, despite their low cost and ubiquity, their chemical and geometric heterogeneity significantly affects the performance and applications of slag-based adsorbents. These challenges notwithstanding, the efficacy of slag-based adsorbents can be significantly enhanced through purposeful activation to increase the specific surface area and density of adsorption sites on the surfaces of adsorbent particles. The synthesis of functionalised adsorbents such as geopolymers, zeolites and layered double hydroxides from silicate and aluminosilicate precursors can also significantly increase the performance of slag-based adsorbents. In addition, the ability to stabilise the dissolved and/or entrained toxic metal species in stable phases in slags, either through controlled post-process fluxing or crystallisation, can significantly enhance the environmental performance of slag-based adsorbents. Most critical in the design of future slag-based adsorbents is the integration of the engineered properties of molten and solidified slags to the recovery and stabilisation of dissolved and/or entrained metals.
James Manchisi; Elias Matinde; Neil A. Rowson; Mark J. H. Simmons; Geoffrey S. Simate; Sehliselo Ndlovu; Brian Mwewa. Ironmaking and Steelmaking Slags as Sustainable Adsorbents for Industrial Effluents and Wastewater Treatment: A Critical Review of Properties, Performance, Challenges and Opportunities. Sustainability 2020, 12, 2118 .
AMA StyleJames Manchisi, Elias Matinde, Neil A. Rowson, Mark J. H. Simmons, Geoffrey S. Simate, Sehliselo Ndlovu, Brian Mwewa. Ironmaking and Steelmaking Slags as Sustainable Adsorbents for Industrial Effluents and Wastewater Treatment: A Critical Review of Properties, Performance, Challenges and Opportunities. Sustainability. 2020; 12 (5):2118.
Chicago/Turabian StyleJames Manchisi; Elias Matinde; Neil A. Rowson; Mark J. H. Simmons; Geoffrey S. Simate; Sehliselo Ndlovu; Brian Mwewa. 2020. "Ironmaking and Steelmaking Slags as Sustainable Adsorbents for Industrial Effluents and Wastewater Treatment: A Critical Review of Properties, Performance, Challenges and Opportunities." Sustainability 12, no. 5: 2118.
The wastes generated from both operational and abandoned coal and metal mining are an environmental concern. These wastes, including acid mine drainage (AMD), are treated to abate the devastating effects they have on the environment before disposal. However, AMD contains valuable resources that can be recovered to subsidize treatment costs. Two of the major constituents of coal AMD are iron and aluminium, which can be recovered and engineered to function as coagulants. This work examines the potential of producing a poly-alumino-ferric sulphate (AMD-PAFS) coagulant from coal acidic drainage solutions. The co-precipitation of iron and aluminium is conducted at pH values of 5.0, 6.0 and 7.0 using sodium hydroxide in order to evaluate the recovery of iron and aluminium as hydroxide precipitates while minimizing the co-precipitation of the other heavy metals. The precipitation at pH 5.0 yields iron and aluminium recovery of 99.9 and 94.7%, respectively. An increase in the pH from 5.0 to 7.0 increases the recovery of aluminium to 99.1%, while the recovery of iron remains the same. The precipitate formed at pH 5.0 is used to produce a coagulant consisting of 89.5% and 10.0% iron and aluminium, respectively. The production of the coagulant is carried out by dissolving the precipitate in 5.0% (w/w) sulphuric acid. Subsequently, the treatment of the brewery wastewater shows that the AMD-PAFS coagulant is as efficient as the conventional poly ferric sulphate (PFS) coagulant. The turbidity removal is 91.9 and 87.8%, while the chemical oxygen demand (COD) removal is 56.0 and 64.0% for AMD-PAFS and PFS coagulants, respectively. The developed process, which can easily be incorporated into existing AMD treatment plants, not only reduces the sludge disposal problems but also creates revenue from waste.
Brian Mwewa; Srećko Stopić; Sehliselo Ndlovu; Geoffrey S. Simate; Buhle Xakalashe; Bernd Friedrich. Synthesis of Poly-Alumino-Ferric Sulphate Coagulant from Acid Mine Drainage by Precipitation. Metals 2019, 9, 1166 .
AMA StyleBrian Mwewa, Srećko Stopić, Sehliselo Ndlovu, Geoffrey S. Simate, Buhle Xakalashe, Bernd Friedrich. Synthesis of Poly-Alumino-Ferric Sulphate Coagulant from Acid Mine Drainage by Precipitation. Metals. 2019; 9 (11):1166.
Chicago/Turabian StyleBrian Mwewa; Srećko Stopić; Sehliselo Ndlovu; Geoffrey S. Simate; Buhle Xakalashe; Bernd Friedrich. 2019. "Synthesis of Poly-Alumino-Ferric Sulphate Coagulant from Acid Mine Drainage by Precipitation." Metals 9, no. 11: 1166.
Jun Zhang; Geoffrey S. Simate; Xiaodi Hu; Mena Souliman; Lubinda F. Walubita. Impact of recycled asphalt materials on asphalt binder properties and rutting and cracking performance of plant-produced mixtures. Construction and Building Materials 2017, 155, 654 -663.
AMA StyleJun Zhang, Geoffrey S. Simate, Xiaodi Hu, Mena Souliman, Lubinda F. Walubita. Impact of recycled asphalt materials on asphalt binder properties and rutting and cracking performance of plant-produced mixtures. Construction and Building Materials. 2017; 155 ():654-663.
Chicago/Turabian StyleJun Zhang; Geoffrey S. Simate; Xiaodi Hu; Mena Souliman; Lubinda F. Walubita. 2017. "Impact of recycled asphalt materials on asphalt binder properties and rutting and cracking performance of plant-produced mixtures." Construction and Building Materials 155, no. : 654-663.
This chapter contains sections titled: IntroductionSynthesis of Biodegradable Polymer–Carbon Nanotube CompositesApplications of Biodegradable Polymer–Carbon Nanotube Composites in Water and Wastewater TreatmentsConcluding Remarks
Geoffrey S. Simate. Biodegradable Polymer-Carbon Nanotube Composites for Water and Wastewater Treatments. Handbook of Composites from Renewable Materials 2017, 15 -33.
AMA StyleGeoffrey S. Simate. Biodegradable Polymer-Carbon Nanotube Composites for Water and Wastewater Treatments. Handbook of Composites from Renewable Materials. 2017; ():15-33.
Chicago/Turabian StyleGeoffrey S. Simate. 2017. "Biodegradable Polymer-Carbon Nanotube Composites for Water and Wastewater Treatments." Handbook of Composites from Renewable Materials , no. : 15-33.
Rhulani N. Ntimbani; Geoffrey S. Simate; Sehliselo Ndlovu. Removal of copper ions from dilute synthetic solution using staple ion exchange fibres: Dynamic studies. Journal of Environmental Chemical Engineering 2016, 4, 3143 -3150.
AMA StyleRhulani N. Ntimbani, Geoffrey S. Simate, Sehliselo Ndlovu. Removal of copper ions from dilute synthetic solution using staple ion exchange fibres: Dynamic studies. Journal of Environmental Chemical Engineering. 2016; 4 (3):3143-3150.
Chicago/Turabian StyleRhulani N. Ntimbani; Geoffrey S. Simate; Sehliselo Ndlovu. 2016. "Removal of copper ions from dilute synthetic solution using staple ion exchange fibres: Dynamic studies." Journal of Environmental Chemical Engineering 4, no. 3: 3143-3150.
Coal, just like other fossil fuels such as oil and natural gas, is mainly used as a non-renewable source of energy. It is a physically unique mineral resource almost totally composed of organic matter (carbon), and a smaller percentage of elements such as hydrogen, oxygen, sulphur, and nitrogen. It is believed that underground coal deposits formed about 250–300 million years ago, when much of the Earth was a swamp covered with thick forest and plant growth. This review explores the use of coal, not as an energy source used for generating electricity, but as a low cost adsorbent in water and wastewater treatment processes. In fact, today, coal-based adsorbents still attract considerable interest in their usage. The review critically analyses the chemical composition, ion-exchange and sorption properties of coal. The use of the as-received coals, demineralized coals, sulphonated coals, calcium-loaded coals, chitosan-doped coals, coal fly ash and coal fly ash derived-zeolite has also been extensively discussed. It is evident from this review that although the pollutant exchange capacities of various types of coal-based adsorbents are significantly lower in comparison to other forms of adsorbents, the substantially lower cost of coal shows a great potential for the utilization of coal as a means to remove a range of pollutants from water and wastewater effluents. However, due to the scarcity of consistent cost information, cost comparisons are difficult to make, and consequently, in this review, such comparisons were not done for the coal-based adsorbents.
Geoffrey S. Simate; Nthabiseng Maledi; Aoyi Ochieng; Sehliselo Ndlovu; Jun Zhang; Lubinda F. Walubita. Coal-based adsorbents for water and wastewater treatment. Journal of Environmental Chemical Engineering 2016, 4, 2291 -2312.
AMA StyleGeoffrey S. Simate, Nthabiseng Maledi, Aoyi Ochieng, Sehliselo Ndlovu, Jun Zhang, Lubinda F. Walubita. Coal-based adsorbents for water and wastewater treatment. Journal of Environmental Chemical Engineering. 2016; 4 (2):2291-2312.
Chicago/Turabian StyleGeoffrey S. Simate; Nthabiseng Maledi; Aoyi Ochieng; Sehliselo Ndlovu; Jun Zhang; Lubinda F. Walubita. 2016. "Coal-based adsorbents for water and wastewater treatment." Journal of Environmental Chemical Engineering 4, no. 2: 2291-2312.
Jun Zhang; Geoffrey S. Simate; Sang Ick Lee; Sheng Hu; Lubinda F. Walubita. Relating asphalt binder elastic recovery properties to HMA crack modeling and fatigue life prediction. Construction and Building Materials 2016, 111, 644 -651.
AMA StyleJun Zhang, Geoffrey S. Simate, Sang Ick Lee, Sheng Hu, Lubinda F. Walubita. Relating asphalt binder elastic recovery properties to HMA crack modeling and fatigue life prediction. Construction and Building Materials. 2016; 111 ():644-651.
Chicago/Turabian StyleJun Zhang; Geoffrey S. Simate; Sang Ick Lee; Sheng Hu; Lubinda F. Walubita. 2016. "Relating asphalt binder elastic recovery properties to HMA crack modeling and fatigue life prediction." Construction and Building Materials 111, no. : 644-651.
The rapid emergence of antimicrobial resistant strains to conventional antimicrobial agents has complicated and prolonged infection treatment and increased mortality risk globally. Furthermore, some of the conventional antimicrobial agents are unable to cross certain cell membranes thus, restricting treatment of intracellular pathogens. Therefore, the disease-causing-organisms tend to persist in these cells. However, the emergence of nanoparticle (NP) technology has come with the promising broad spectrum NP-antimicrobial agents due to their vast physiochemical and functionalization properties. In fact, NP-antimicrobial agents are able to unlock the restrictions experienced by conventional antimicrobial agents. This review discusses the status quo of NP-antimicrobial agents as potent broad spectrum antimicrobial agents, sterilization and wound healing agents, and sustained inhibitors of intracellular pathogens. Indeed, the perspective of developing potent NP-antimicrobial agents that carry multiple-functionality will revolutionize clinical medicine and play a significant role in alleviating disease burden.
Clarence Yah; Geoffrey S. Simate. Nanoparticles as potential new generation broad spectrum antimicrobial agents. DARU Journal of Pharmaceutical Sciences 2015, 23, 1 -14.
AMA StyleClarence Yah, Geoffrey S. Simate. Nanoparticles as potential new generation broad spectrum antimicrobial agents. DARU Journal of Pharmaceutical Sciences. 2015; 23 (1):1-14.
Chicago/Turabian StyleClarence Yah; Geoffrey S. Simate. 2015. "Nanoparticles as potential new generation broad spectrum antimicrobial agents." DARU Journal of Pharmaceutical Sciences 23, no. 1: 1-14.
Jun Zhang; Lubinda F. Walubita; Abu N.M. Faruk; Pravat Karki; Geoffrey S. Simate. Use of the MSCR test to characterize the asphalt binder properties relative to HMA rutting performance – A laboratory study. Construction and Building Materials 2015, 94, 218 -227.
AMA StyleJun Zhang, Lubinda F. Walubita, Abu N.M. Faruk, Pravat Karki, Geoffrey S. Simate. Use of the MSCR test to characterize the asphalt binder properties relative to HMA rutting performance – A laboratory study. Construction and Building Materials. 2015; 94 ():218-227.
Chicago/Turabian StyleJun Zhang; Lubinda F. Walubita; Abu N.M. Faruk; Pravat Karki; Geoffrey S. Simate. 2015. "Use of the MSCR test to characterize the asphalt binder properties relative to HMA rutting performance – A laboratory study." Construction and Building Materials 94, no. : 218-227.
Rhulani N. Ntimbani; Geoffrey S. Simate; Sehliselo Ndlovu. Removal of copper ions from dilute synthetic solution using staple ion exchange fibres: Equilibrium and kinetic studies. Journal of Environmental Chemical Engineering 2015, 3, 1258 -1266.
AMA StyleRhulani N. Ntimbani, Geoffrey S. Simate, Sehliselo Ndlovu. Removal of copper ions from dilute synthetic solution using staple ion exchange fibres: Equilibrium and kinetic studies. Journal of Environmental Chemical Engineering. 2015; 3 (2):1258-1266.
Chicago/Turabian StyleRhulani N. Ntimbani; Geoffrey S. Simate; Sehliselo Ndlovu. 2015. "Removal of copper ions from dilute synthetic solution using staple ion exchange fibres: Equilibrium and kinetic studies." Journal of Environmental Chemical Engineering 3, no. 2: 1258-1266.
Geoffrey S. Simate; Sehliselo Ndlovu. The removal of heavy metals in a packed bed column using immobilized cassava peel waste biomass. Journal of Industrial and Engineering Chemistry 2015, 21, 635 -643.
AMA StyleGeoffrey S. Simate, Sehliselo Ndlovu. The removal of heavy metals in a packed bed column using immobilized cassava peel waste biomass. Journal of Industrial and Engineering Chemistry. 2015; 21 ():635-643.
Chicago/Turabian StyleGeoffrey S. Simate; Sehliselo Ndlovu. 2015. "The removal of heavy metals in a packed bed column using immobilized cassava peel waste biomass." Journal of Industrial and Engineering Chemistry 21, no. : 635-643.
Jiusu Li; Jeongho Oh; Bhaven Naik; Geoffrey S. Simate; Lubinda F. Walubita. Laboratory characterization of cracking-resistance potential of asphalt mixes using overlay tester. Construction and Building Materials 2014, 70, 130 -140.
AMA StyleJiusu Li, Jeongho Oh, Bhaven Naik, Geoffrey S. Simate, Lubinda F. Walubita. Laboratory characterization of cracking-resistance potential of asphalt mixes using overlay tester. Construction and Building Materials. 2014; 70 ():130-140.
Chicago/Turabian StyleJiusu Li; Jeongho Oh; Bhaven Naik; Geoffrey S. Simate; Lubinda F. Walubita. 2014. "Laboratory characterization of cracking-resistance potential of asphalt mixes using overlay tester." Construction and Building Materials 70, no. : 130-140.
The inherent quality of perpetual pavement (PP) governs its performance, which consequently influences the frequency and level of the potential accidents during the whole service life. This paper presents the ground-penetrating radar (GPR) as a nondestructive testing (NDT) tool that was utilized for construction monitoring and evaluation of Texas (USA) perpetual pavements. The currently existing Texas PP sections typically consist of hot-mix asphalt layers of over 350-mm total thickness supported on a 200-mm-thick treated (6 % lime or 2 % cement) base, which is resting on a well-compacted in situ subgrade soil. Overall, the results indicate that the GPR has great potential as an effective NDT tool for aiding with the construction quality monitoring, forensic investigations, and structural/performance evaluation of PP structures. In particular, the GPR is useful in determining pavement layer thicknesses, assessing compaction uniformity, locating areas of moisture retention, identifying low-density spots and localized high voided areas, indicative assessment of vertical segregation and debonding, and quality assessment of construction joints. Additionally, the current GPR system has the advantage of rapidly and continuously collecting pavement data up to a depth of 610 mm, together with integrated video images and a GPS system, over any desired highway length while traveling at a nominal speed of about 113 km/h without disturbing conventional traffic.
Jiusu Li; Lubinda F. Walubita; Geoffrey S. Simate; Allex E. Alvarez; Wenting Liu. Use of ground-penetrating radar for construction monitoring and evaluation of perpetual pavements. Natural Hazards 2014, 75, 141 -161.
AMA StyleJiusu Li, Lubinda F. Walubita, Geoffrey S. Simate, Allex E. Alvarez, Wenting Liu. Use of ground-penetrating radar for construction monitoring and evaluation of perpetual pavements. Natural Hazards. 2014; 75 (1):141-161.
Chicago/Turabian StyleJiusu Li; Lubinda F. Walubita; Geoffrey S. Simate; Allex E. Alvarez; Wenting Liu. 2014. "Use of ground-penetrating radar for construction monitoring and evaluation of perpetual pavements." Natural Hazards 75, no. 1: 141-161.
The production of carbon nanostructures, including carbon nanotubes (CNTs), by chemical vapour deposition (CVD) occurs by thermally induced decomposition of carbon-containing precursors. The decomposition of the feedstock leading to intermediate reaction products is an important step, but rarely incorporated in rate equations, since it is generally assumed that carbon diffusion through or over the catalyst nanoparticles is the rate-limiting step in the production of CNTs. Furthermore, there is no kinetic model to date for the production of CNTs from carbon dioxide. These aspects are addressed in this study with the aid of a series of experiments conducted in a floating catalytic CVD reactor in which the effects of reactor temperature, concentration and flow rate of CO2 were investigated. A simple rate equation for the reductive adsorption of CO2 onto the catalyst surface followed by carbon diffusion leading to the production of CNTs is proposed as follows: d[CNT]/dt = K[CO2], where K is proportional to the diffusion coefficient of carbon. The derived kinetic model is used to calculate the amount of CNTs for a given concentration of CO2, and the experimentally measured data fits the simple rate equation very well at low carbon dioxide concentration.
Geoffrey S. Simate; Kapil Moothi; M. Meyyappan; Sunny E. Iyuke; Sehliselo Ndlovu; Rosemary Falcon; Mike Heydenrych. Kinetic model of carbon nanotube production from carbon dioxide in a floating catalytic chemical vapour deposition reactor. RSC Advances 2014, 4, 9564 .
AMA StyleGeoffrey S. Simate, Kapil Moothi, M. Meyyappan, Sunny E. Iyuke, Sehliselo Ndlovu, Rosemary Falcon, Mike Heydenrych. Kinetic model of carbon nanotube production from carbon dioxide in a floating catalytic chemical vapour deposition reactor. RSC Advances. 2014; 4 (19):9564.
Chicago/Turabian StyleGeoffrey S. Simate; Kapil Moothi; M. Meyyappan; Sunny E. Iyuke; Sehliselo Ndlovu; Rosemary Falcon; Mike Heydenrych. 2014. "Kinetic model of carbon nanotube production from carbon dioxide in a floating catalytic chemical vapour deposition reactor." RSC Advances 4, no. 19: 9564.
The volume of industrial and domestic wastewater is increasing significantly year by year with the change in the lifestyle based on mass consumption and mass disposal brought about by the dramatic development of economies and industries. Therefore, effective advanced wastewater treatment is required because wastewater contains a variety of constituents such as particles, organic materials, and emulsion depending on the resource. However, residual chemicals that remain during the treatment of wastewaters form a variety of known and unknown by-products through reactions between the chemicals and some pollutants. Chronic exposure to these by-products or residual chemicals through the ingestion of drinking water, inhalation and dermal contact during regular indoor activities (e.g., showering, bathing, cooking) may pose cancer and non-cancer risks to human health. For example, residual aluminium salts in treated water may cause Alzheimer's disease (AD). As for carbon nanotubes (CNTs), despite their potential impacts on human health and the environment having been receiving more and more attention in the recent past, existing information on the toxicity of CNTs in drinking water is limited with many open questions. Furthermore, though general topics on the human health impacts of traditional water treatment chemicals have been studied, no comparative analysis has been done. Therefore, a qualitative comparison of the human health effects of both residual CNTs and traditional water treatment chemicals is given in this paper. In addition, it is also important to cover and compare the human health effects of CNTs to those of traditional water treatment chemicals together in one review because they are both used for water treatment and purification.
Geoffrey S. Simate; Sunny E. Iyuke; Sehliselo Ndlovu; Mike Heydenrych; Lubinda F. Walubita. Human health effects of residual carbon nanotubes and traditional water treatment chemicals in drinking water. Environment International 2012, 39, 38 -49.
AMA StyleGeoffrey S. Simate, Sunny E. Iyuke, Sehliselo Ndlovu, Mike Heydenrych, Lubinda F. Walubita. Human health effects of residual carbon nanotubes and traditional water treatment chemicals in drinking water. Environment International. 2012; 39 (1):38-49.
Chicago/Turabian StyleGeoffrey S. Simate; Sunny E. Iyuke; Sehliselo Ndlovu; Mike Heydenrych; Lubinda F. Walubita. 2012. "Human health effects of residual carbon nanotubes and traditional water treatment chemicals in drinking water." Environment International 39, no. 1: 38-49.
Coagulation and flocculation treatment processes play a central role in the way wastewater effluents are managed. Their primary function is particle removal that can impart colour to a water source, create turbidity, and/or retain bacterial and viral organisms. This study was carried out to investigate whether carbon nanotubes (CNTs) can be used as heterogeneous coagulants and/or flocculants in the pretreatment of brewery wastewater. A series of experiments were conducted in which the efficiencies of pristine and functionalised CNTs were compared with the efficiency of traditional ferric chloride in a coagulation/flocculation process. Turbidity and chemical oxygen demand (COD), including the zeta potential were used to monitor the progress of the coagulation/flocculation process. Both pristine and functionalised CNTs demonstrated the ability to successfully coagulate colloidal particles in the brewery wastewater. Overall, ferric chloride was found to be a more effective coagulant than both the pristine and functionalised CNTs.
Geoffrey S. Simate; Sunny E. Iyuke; Sehliselo Ndlovu; Mike Heydenrych. The heterogeneous coagulation and flocculation of brewery wastewater using carbon nanotubes. Water Research 2011, 46, 1185 -1197.
AMA StyleGeoffrey S. Simate, Sunny E. Iyuke, Sehliselo Ndlovu, Mike Heydenrych. The heterogeneous coagulation and flocculation of brewery wastewater using carbon nanotubes. Water Research. 2011; 46 (4):1185-1197.
Chicago/Turabian StyleGeoffrey S. Simate; Sunny E. Iyuke; Sehliselo Ndlovu; Mike Heydenrych. 2011. "The heterogeneous coagulation and flocculation of brewery wastewater using carbon nanotubes." Water Research 46, no. 4: 1185-1197.
Clarence S. Yah; Kapil Moothi; Kwena S. Maphutha; Sunny E. Iyuke; Geoffrey S. Simate. Synthesis of Large Carbon Nanotubes from Ferrocene: The Chemical Vapour Deposition Technique. Trends in Applied Sciences Research 2011, 6, 1270 -1279.
AMA StyleClarence S. Yah, Kapil Moothi, Kwena S. Maphutha, Sunny E. Iyuke, Geoffrey S. Simate. Synthesis of Large Carbon Nanotubes from Ferrocene: The Chemical Vapour Deposition Technique. Trends in Applied Sciences Research. 2011; 6 (11):1270-1279.
Chicago/Turabian StyleClarence S. Yah; Kapil Moothi; Kwena S. Maphutha; Sunny E. Iyuke; Geoffrey S. Simate. 2011. "Synthesis of Large Carbon Nanotubes from Ferrocene: The Chemical Vapour Deposition Technique." Trends in Applied Sciences Research 6, no. 11: 1270-1279.
Based on a master-curve, mixture properties can be predicted or interpolated at different temperatures and loading times of interest from a limited set of laboratory test data. This paper presents a comparative assessment of three methods used for generating the relaxation modulus (E(t)) master-curves of hot-mix asphalt (HMA). These methods were the Arrhenius, the Williams–Landel–Ferry (WLF), and an optimization technique with the sum of square error (SSE) method. Experimental data (E(t) values) for different HMA mixtures were gathered by performing uniaxial loading (strain-controlled) relaxation modulus tests (RMT). The process for evaluating the three methods was based on using the same RMT laboratory data to generate E(t) master-curves and then comparing the best fit functions. Corresponding results suggested that the SSE method generated the best fit functions relative to the measured E(t) data. Unlike the Arrhenius and WLF models, the SSE is independent of external empirical material constants in its application and is universally applicable to any given material or HMA mix type. However, this study also demonstrated that both the Arrhenius and WLF methods can produce satisfactory (and in fact equivalent results) if appropriate constants, that are material or mix type specific, are used. Conclusively, the findings of this paper suggested that satisfactory application of the Arrhenius and WLF methods should be with caution, in particular with respect to the material constants. Otherwise, the SSE method proved to be more accurate and would be preferred.
Lubinda F. Walubita; Allex E. Alvarez; Geoffrey S. Simate. Evaluating and comparing different methods and models for generating relaxation modulus master-curves for asphalt mixes. Construction and Building Materials 2011, 25, 2619 -2626.
AMA StyleLubinda F. Walubita, Allex E. Alvarez, Geoffrey S. Simate. Evaluating and comparing different methods and models for generating relaxation modulus master-curves for asphalt mixes. Construction and Building Materials. 2011; 25 (5):2619-2626.
Chicago/Turabian StyleLubinda F. Walubita; Allex E. Alvarez; Geoffrey S. Simate. 2011. "Evaluating and comparing different methods and models for generating relaxation modulus master-curves for asphalt mixes." Construction and Building Materials 25, no. 5: 2619-2626.
Back matter pages come after the papers or chapters in a published work and may include appendixes, references, and indexes.
Lubinda F. Walubita; Louw Du Plessis; Shin-Che Huang; Geoffrey S. Simate; Zhaohui Liu. Back Matter. New Technologies in Construction and Rehabilitation of Portland Cement Concrete Pavement and Bridge Deck Pavement 2009, 1 .
AMA StyleLubinda F. Walubita, Louw Du Plessis, Shin-Che Huang, Geoffrey S. Simate, Zhaohui Liu. Back Matter. New Technologies in Construction and Rehabilitation of Portland Cement Concrete Pavement and Bridge Deck Pavement. 2009; ():1.
Chicago/Turabian StyleLubinda F. Walubita; Louw Du Plessis; Shin-Che Huang; Geoffrey S. Simate; Zhaohui Liu. 2009. "Back Matter." New Technologies in Construction and Rehabilitation of Portland Cement Concrete Pavement and Bridge Deck Pavement , no. : 1.