School of Pure and Applied Sciences: Recent submissions
Now showing items 81-100 of 171
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Effects of Biocementation on some Properties of Cement-Based Materials Incorporating Bacillus Species Bacteria
(Taylor & Francis, 2019)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 ... -
Review of Carbonation Resistance in Hydrated Cement Based Materials
(Elsevier, 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 Composite Material from the Copolymerized Polyphenolic Matrix with treated Cassava Peels Starch
(Elsevier, 2020)Conventional binders in the particleboards formulation involve use of formaldehyde resins. Epidemiologic studies show that formaldehyde is carcinogenic. Efforts to reduce formaldehyde emissions by use of scavengers has not ... -
Chloride Diffusivity in Blended Cement Made from Selected Industrial and Agrowastes
(Hindawi, 2020)This paper reports study findings on the diffusivity of chloride ions in potential blended cement. The cement, abbreviated as PCDC, was made from blending ordinary Portland cement (OPC) with dried calcium carbide residue ... -
A Review on Pyroprocessing Techniques for Selected Wastes Used for Blended Cement Production Applications
(Elsevier, 2020)Pyroprocessing is an important stage in cement manufacturing. In this process, materials are subjected to high temperatures so asto cause a chemical or physical change. Its control improves efficiency in energy utilization ... -
Study on the Effect of Thiobacillus Intermedius Bacteria on the Physico-Mechanical Properties of Mortars of Ordinary Portland Cement
(PubMed, 2020)Most of concrete structural failures are attributed to poor workmanship and poor engineering designs. Some microorganisms present in sewer systems can degrade the concrete and/or mortar. Concrete failures due to microbial ... -
Physico-Chemical Properties of Kenyan made Calcined Clay-Limestone Cement (LC3).
(Elsevier, 2020)In Kenya fired clay bricks are mainly used as construction materials. However, vast quantities of these Fired Rejected Clay Bricks (FRCB) generated are rejected annually as a result of improper calcination or demolition ... -
Prediction of Compressive Strength of Calcined Clay Based Cement Mortars Using Support Vector Machine and Artificial Neural Network Techniques
(Research Gate, 2020)Prediction of strength in cement based materials is vital in construction industry as it forms the basis upon which important tasks can be performed such as the time for mortar form removal, project scheduling and quality ... -
Effects of Sulfuric Acid Attack on Hydrated Calcined Clay Limestone Cement Mortars
(Taylor & Francis, 2020)The paper presents experimental findings on the performance of Limestone Calcined Clay Cement (LC3) in acidic media. LC3 was made by inter-grinding a blend of 50 % clinker with ground 30 % Fired Rejected Clay Bricks (FRCB), ... -
A numerical investigation of the effect of curvature and Reynolds number to radial velocity in a curved porous pipe
(International Journal of Advances in Applied Mathematics and Mechanics, 2017)Different irrigation methods are being used in agriculture. However, due to scarcity of water, irrigation methods that use water efficiently are needed. The motivation of this study is the increasing use of porous pipes ... -
Estimation of Non-smooth Functionals in Hilbert Sample Space Using the Edgeworth Expansions
(Asian Journal of Probability and Statistics, 2019)An arbitrary non-smooth functional is estimated using a nonparametric set-up. Exploratory data analysis methods are relied on to come up with the functional form for the sample to allow both robustness and optimality to ... -
The Possibility of Angle Trisection (A Compass-Straightedge Construction)
(Journal of Mathematics and System Science, 2017)The objective of this paper is to provide a provable solution of the ancient Greek problem of trisecting an arbitrary angle employing only compass and straightedge (ruler).(Pierre Laurent Wantzel, 1837) obscurely presented ... -
The Cube Duplication Solution (A Compass-straightedge (Ruler) Construction)
(International Journal of Mathematics Trends and Technology, 2017)This paper objectively presents a provable construction of generating a length of magnitude;, as the geometrical solution for the ancient classical problem of doubling the volume of a cube. Cube duplication is believed to ... -
Material Properties of RE-Doped Ln (Ln= Y, La) oxides and oxysulfides phosphors for red-emitting devices
(University of the Free State, 2015)Structural and optical properties of Eu3+-doped Ln (Ln=Y, La) oxide and oxysulfide nano crystals synthesized by sol-combustion method were analysed as a function of host to fuel ratio. Structural characterization shows ... -
Effects of Grafting Azacrown Ether on Thermal and Swelling Properties of Chitosan Films
(Multidisciplinary Digital Publishing Institute, 2017-11-17)The thermal and swelling properties of a series of azacrown ether-crosslinked chitosans prepared with varying molar amounts of N, N-diallyl-7, 13-diaza-1, 7, 10, 16-tetraoxa-dibenzo-18-crown-6 (molar equivalents ranging ... -
Robust Variance Estimation by Linearization Techniques for Poverty Indicators
(Southern Africa Mathematical Sciences Association, 2018)The need for a reliable and equitable means of measuring population disparity and providing guidelines on implementation of policy decisions has necessitated the search for a precise estimating scheme for poverty indicators. ... -
Robust Estimation of Finite Population Totals Using a Model Based Approach in the Presence of Two Auxiliary Variables
(International Journal of Data Science and Analysis, 2018)The utilization of auxiliary information during surveys increases the accuracy of estimators, thereby giving more reliable estimates of the population parameters of interest. It has been established that the presence of ... -
Bayesian Estimation of Survivor Function for Censored Data Using Lognormal Mixture Distributions
(IOSR Journal of Mathematics, 2017)We use Bayesian methods to fit a lognormal mixture model with two components to right censored survival data to estimate the survivor function. This is done using a simulation-based Bayesian framework employing a prior ... -
Longitudinal Survey, Nonmonotone, Nonresponse, Imputation, Nonparametric Regression
(Scientific Research Publishing, 2016)The study focuses on the imputation for the longitudinal survey data which often has nonignorable nonrespondents. Local linear regression is used to impute the missing values and then the estimation of the time-dependent ... -
Investigating the Asymptotic Properties of Some Estimators for Panel Data Regression Model with Individual Effects
(International Journal of Statistics & Economics, 2015)