Browsing Articles: Department of Physical Sciences by Issue Date
Now showing items 21-40 of 59
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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 ... -
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 ... -
Concentration of Laterites Using Biomass
(Kenya Industrial Property Institute, 2015-06-11)A method of concentrating iron in laterites to make the iron extraction process economical is disclosed. Concentration using biomass yields higher levels of iron by using appropriate ratio of biomass: laterites. The ... -
Structure,morphologyandopticalpropertiesofundopedand MN-doped ZnO(1 x)Sx nano-powderspreparedbyprecipitation method
(Elsevier, 2015-08)The undopedandMn-dopedZnO(1 x)Sx nano-powders weresuccessfullysynthesizedbyprecipitation method withoutusinganycappingagent.Itsstructure,morphology,elementalanalysis,opticaland luminescence propertiesweredeterminedbysc ... -
Structural and luminescence properties of SrAl2O4:Eu2+,Dy3+,Nd3+ phosphor thin films grown by pulsed laser deposition
(Elsevier, 2015-09)Thin films of Eu2þ doped and Dy3þ,Nd3þ co-doped Strontium Aluminate (SrAl2O4:Eu2þ,Dy3þ,Nd3þ) phosphors were grown on Si(100) substrates by a pulsed laser deposition (PLD) technique using a 266 nm Nd:YAG pulsed laser under ... -
Trap characteristics of UV-activated Y3(Al,Ga)5O12:Ce3+phosphorsA
(Elsevier, 2015-12)tThis paper reports on the trap characteristics of commercially obtained Y3(Al,Ga)5O12:Ce3+phosphorpowder. The effects of UV irradiation time and different heating rates have been discussed using differentthermoluminescence ... -
Effect of Ga3+ and Gd3+ ions substitution on the structural and optical properties of Ce3+-doped yttrium aluminium garnet phosphor nanopowders
(John Wiley & Sons, 2016-01)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 ... -
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 ... -
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 ... -
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 ... -
Thermal Resistivity of Chemically Activated Calcined Clays-Based Cements
(Springer, 2017-10)The study investigated the effects of selected potential chemical activators on thermal resistivity of calcined clay based cement mortars. 0.5 M Na2SO4 and 0.5 M NaOH were used as activator solutions. The chemical ... -
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 ... -
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 ... -
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 ... -
Characterization of Prototype Formulated Particleboards from Agroindustrial Lignocellulose Biomass Bonded with Chemically Modified Cassava Peel Starch
(Hindawi, 2019)Conventional methods of making particleboards utilize wood chips. +is has resulted in a decrease in the tree cover due to the increase in wood demand. +e effect has been climatic change. Wood is bound using phenol ... -
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 ... -
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 ...