Journals: Department of Physical Sciences
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Effects of biocementation on some properties of cement-based materials incorporating Bacillus Species bacteria – a review
(Taylor and Francis, 2019-11)There is a growing need in the construction industry to improve transfer and durability aspects of Portland pozzolana cement. Ureolytic bacteria have recently emerged as potential micro-organisms well known for precipitation ... -
Influence of Lysinibacillus sphaericus on compressive strength and water sorptivity in microbial cement mortar
(Elsevier, 2019-11)Cement structures are subject to degradation either by aggressive media or development of micro/macro cracks which create external substance ingress pathways. Microbiocementation can be employed as a self-intelligent solution ... -
Effects of biocementation on some properties of cement-based materials incorporating Bacillus Species bacteria – a review
(Taylor and Francis, 2019-11)There is a growing need in the construction industry to improve transfer and durability aspects of Portland pozzolana cement. Ureolytic bacteria have recently emerged as potential micro-organisms well known for precipitation ... -
Influence of Lysinibacillus sphaericus on compressive strength and water sorptivity in microbial cement mortar
(Elsevier, 2019-11)Cement structures are subject to degradation either by aggressive media or development of micro/macro cracks which create external substance ingress pathways. Microbiocementation can be employed as a self-intelligent solution ... -
Copper extraction by wet chemical method
(Elsevier, 2018-07)In many countries large deposits of copper with no locally established copper based industries occur because known methods for extraction are prohibitively expensive and unaffordable. This study reports on an affordable and ... -
Properties of activated blended cement containing high content of calcined clay
(Elsevier, 2018-08)This paper presents findings of an experimental investigation on sodium sulphate (Na2SO4) activated calcined clay e Portland cement blends in sulphuric acid media. Calcined clays were blended with Ordinary Portland Cement ... -
Review of Carbonation Resistance in Hydrated Cement Based Materials
(Hindawi, 2019)Blended cements are preferred to Ordinary Portland Cement (OPC) in construction industry due to costs and technological and environmental benefits associated with them. Prevalence of significant quantities of carbon dioxide ... -
Properties of activated blended cement containing high content of calcined clay
(Elsevier, 2018-08)This paper presents findings of an experimental investigation on sodium sulphate (Na2SO4) activated calcined clay e Portland cement blends in sulphuric acid media. Calcined clays were blended with Ordinary Portland Cement ... -
Carbon storage in the seagrass meadows of Gazi Bay, Kenya
(2017-05-10)Vegetated marine habitats are globally important carbon sinks, making a significant contribution towards mitigating climate change, and they provide a wide range of other ecosystem services. However, large gaps in knowledge ... -
Effects of Temperature on Ilmenite During Concentration of Iron in Laterites Using Charcoal and Separation using Magnetic Separation
(IJSET, 2014-06)Effect of temperature on ilmenite minerals found in laterites has been investigated. It was found that during reduction of iron minerals in laterites to magnetite using charcoal at temperatures of about 500-700oC, ... -
Magnetic Concentration of Iron in Lateritic Soils from Kamahuha, Murang’a County, in Kenya using Carbon Monoxide Generated In-Situ
(IJSET, 2014-08)Chemical and Mineral Analyses of laterites from selected sites in Kamahuha area of Murang’a County, in the Republic of Kenya, have been carried out with particular interest in the levels of iron and the type of minerals ... -
Physicochemical Performance of Portland-Rice Husk Ash-Calcined Clay-Dried Acetylene Lime Sludge Cement in Sulphate and Chloride Media
(Hindawi, 2019-03)This paper reports leach and/or intake of SO42−, Cl−, Ca2+, Na+, and K+ from and/or into cement mortar cubes made from a novel cementious material in naturally encountered environmental simulated media. The paper also ... -
Effects of Chlorides on Corrosion of Simulated Reinforced Blended Cement Mortars
(Hindawi, 2019-03)Cementitious materials are subject to degradation when subjected to corrosive chloride media. This paper reports the experimental results on corrosion studies conducted on a potential cementitious material, PCDC, made ... -
Copper extraction by wet chemical method
(Elsevier, 2018-07)In many countries large deposits of copper with no locally established copper based industries occur because known methods for extraction are prohibitively expensive and unaffordable. This study reports on an affordable and ... -
Review of Carbonation Resistance in Hydrated Cement Based Materials
(Hindawi, 2019-01)Blended cements are preferred to Ordinary Portland Cement (OPC) in construction industry due to costs and technological and environmental benefits associated with them. Prevalence of significant quantities of carbon dioxide ... -
Equilibrium Studies for Adsorption of Zn2+ on to Acid Treated Kikuyu Grass Pennisetum Clandestinum Biomass
(2016-04)The feasibility of using Pennisetum clandestinum biomass as low-cost adsorbent for the removal of Zn2+ was investigated in batch studies. The Freundlich, Langmuir,Dubinin Raduskevich and Temkin adsorption isotherms were ... -
Thermoluminescence of SrAl2O4:Eu2þ, Dy3þ: Kinetic analysis of a composite-peak
(Elsevier, 2016-12)The kinetic analysis of thermoluminescence of beta-irradiated SrAl2O4:Eu2þ,Dy3þ is reported. The glowcurve is dominated by an apparently-single peak. It has been demonstrated using a number of tests including partial ... -
Effect of Ga3+ and Gd3+ ions substitution on the structural and optical properties of Ce3+-doped yttrium aluminium garnet phosphor nanopowders
(John Wiley & Sons, 2016-03)ABSTRACT: The structural and optical properties of commercially obtained Y3Al5O12:Ce3+ phosphor were investigated by replacing Al3+ with Ga3+ and Y3+ with Gd3+ in the Y3Al5O12:Ce3+ structure to form Y3(Al,Ga)5O12:Ce3+ and ... -
A preliminary study of Thermoluminescence of beta-irradiated SrAl2O4:Eu2+, Dy3+ phosphors
(2015)Eu2+ doped and Dy3+ co-doped strontium aluminate (SrAl2O4:Eu2+,Dy3+) phosphors were synthesized by the solution - combustion technique at 500 oC using urea as a reducer, a widely known method for preparing nano sized ... -
Characterization of cerium doped yttrium gadolinium aluminate garnet (Y-Gd)3Al5O12:Ce3+ phosphor thin films fabricated by pulsed laser deposition
(2015)Thin films of cerium doped yttrium gadolinium aluminate garnet (Y-Gd)3Al5O12:Ce3+ (YGAG:Ce) were grown on Si(100) substrates by a pulsed laser deposition (PLD) technique using a 266 nm Nd:YAG pulsed laser under varying ...