Browsing by Author "Odhiambo, Jared Oloo"

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EDXRF spectroscopic elemental analysis for efficacy of Kibabii University sewage treatment System
(Open Access Library Journal, 2018-10-18) Situma, Yonah; Odhiambo, Jared Oloo; Makokha, John Wanjala
Elemental analysis of sewage effluents in Kibabii sewage treatment system was achieved via Energy-Dispersive X-Ray Fluorescence (EDXRF) spectroscopy with the aim of assessing the efficacy of the treatment system. Concentrations of lead (Pb), mercury (Hg), cadmium (Cd) and arsenic (As) were measured based on clay soil “standards” in concentration range for Pb, Hg and As as 12.7 ppm, 14.3 ppm and 8.83 ppm respectively for certification. Among other probable reference materials, clay soil “standards” were used for certification in this work because of similarity in matrix composition with the sediments. The concentration for Hg, Pb, and As in the sewage sediments were 10.65 ± 2.28 ppm, 8.86 ± 2.92 ppm and 3.41 ± 2.18 ppm respectively in lagoon A. In lagoon B the levels were 3.82 ± 0.56 ppm, 6.35 ± 1.50 ppm and 1.67 ± 0.53 ppm respectively. Lagoon C showed a reduction in the levels with 3.74 ± 1.39 ppm for Hg and 2.30 ± 0.27 ppm for Pb. As was not detected in lagoon C, on the other hand, Cd was not detected in all the lagoons. The efficacies in the treatment varied from 30.34% - 51.78%, 37.63% - 65.41% and 76.63% - 84.81% for lagoon A, B and C respectively. The study was successful in quantifying the heavy elements in the lagoons from which the efficacy in the treatment process was determined. The study provided awareness on the elemental concentration levels in the Kibabii University sewage treatment system, hence creating awareness on what is released into River Kibabii. With this information, the surrounding community and the University can partner in order to mitigate the effects of heavy metals in the effluents in future due to the growth of the University day by day.
Effect of duo fermion spin on the specific heat and entropy of a mixture of helium isotopes
(Journal of Multidisciplinary Engineering Science and Technology (, 2018-10-01) Lusamamba, Simon Mwatulo; Sakwa, Thomas W.; Odhiambo, Jared Oloo
Spin normally determines the character, rate of collision and subsequently the properties of ultracold systems. This study investigated the effect of double spin degeneracy on the thermodynamic properties of Helium-3 and Helium-4 isotopes specifically the specific heat and entropy of a grand canonical ensemble. The approach used was statistical in nature where permutation and exclusion was done on fermions and bosons. From thermodynamics, the expression of partition function which was used to derive other expressions of specific heat and entropy as temperature dependence. Specific heat and entropy were found to increase with temperature. The kink in specific heat at a temperature of 35K implied that there was a phase transition.
Internal energy of a grand canonical ensemble of a mixture of helium isotopes with duo-fermion spin degeneracy
(Centre for Info Biotechnology-IJPMS, 2015-12-01) Lusamamba, Simon Mwatulo; Sakwa, Thomas W.; Odhiambo, Jared Oloo; Oketch, Vincent O.; Ochola, Alphayo
We have considered a system consisting of a mixture of helium isotopes 3He-4He interacting weakly in pairs. The partition function of the system with duo-spin and varying number of bosons and fermions is developed to bring out the superfluid properties of the system. The study focused on a Grand Canonical ensemble of 3He - 4He isotopes whose superfluid properties have been determined by distinctively singling out the duo spin component. The internal energy was established algebraically, analyzed and found out to be increasing with temperature. For high temperatures, internal energy remains constant due to particle saturation.
Long term assessment of aerosol radiative forcing over selected sites of East Africa
(scientific Research Publishing, 2018-03-08) Makokha, John Wanjala; Odhiambo, Jared Oloo; shem, Godfrey Juma
Atmospheric aerosols have contributed to radiative forcing through direct and indirect mechanisms. Aerosol effects are important in computing radiative forcing estimates for the past, current and future climate. In this study, a comprehensive assessment of regional aerosol radiative forcing, Optical Properties of Aerosol and Clouds (OPAC) model (wavelength range of 0.25 - 4.0 μm) over selected sites in East Africa was done. Aerosol optical properties constituted the inputs of a Radiative Transfer Model (RTM). Optical properties investigated included Aerosol Optical Depth (AOD), Single Scattering Albedo (SSA) and Asymmetry Parameter (AP). Aerosol Radiative Forcing (ARF) during the study period at the surface (SFC), top of the atmosphere (TOA) and the atmosphere (ATM) was estimated to be –18.4 ± 1.4 W∙m−2, +1.1 ± 0.3 W∙m−2 and +19.5 ± 2.5 W∙m−2, respectively. This corresponds to an increment in net atmospheric forcing at a heating rate of about 0.55 ± 0.05 K/day (0.41 ± 0.03 to 0.78 ± 0.03 K/day) in the lower troposphere. The study points out the significant role played by atmospheric aerosols in climate modification over the area of study. It is recommended that a further assessment be done in view of uncertainties that may impact on the findings and which were not within the scope of this research.
Specific heat and entropy of a three electron model in bismuth based cuprate superconductor
(Science Publishing Group : World Journal of applied physics, 2018-06-11) Odhiambo, Jared Oloo; Makokha, John Wanjala
A theoretical study considering Bi2201, Bi2212 and Bi2223 bismuth based cuprates whose critical Temperatures (TC) are 20K, 95K and 110K with one, two and three CuO2 planes respectively; based on a three electron model in Bismuth based cuprates oxide shows that there is a direct correlation between energy of interaction and the number of CuO2 planes at the TC. The specific heat for a mole of Bismuth based cuprates at TC was found to be 7.471×10-24JK-1 regardless of the number of CuO2 planes; though the specific heat per unit mass, Sommerfeld coefficient as well as entropy per unit mass decreased with an increase in the number of CuO2 planes.The entropy of a mole of Bismuth based cuprates at TC was found to be 5.603×10-24JK-1 irrespective of the TC or mass. The peak Sommerfeld coefficient temperature was noted to occur at the ratio T/TC=0.66 in the bismuth based cuprates.
Thermodynamic properties of yttrium based cuprate due to electron-cooper pair interaction using BVT
(Open Access Library Journal, 2018-10-15) Mukubwa, Abel Wanjala; Odhiambo, Jared Oloo; Makokha, John Wanjala
Since the discovery of high temperature superconductivity (HTSC), there have been varied results concerning the high pairing energy in the unconventional superconductivity. In an attempt to unearth the mechanism behind the high pairing energy, we study a model in which an excited electron interacts with a Cooper pair. The interaction was studied earlier on using second quantization which depended on a wave function. We now use Bogoliubov- Valatini transformation (BVT) that is independent of the wave function to study the thermodynamic properties due to the interaction between an electron and a Cooper pair in a Yttrium based cuprate. The interaction energy increases with temperature and at T = 93 K ; we record the interaction energy of 2.173 meV and the specific heat of 4.669 J∙mol−1∙K−1. The entropy of this system is found to be 5.11 mJ∙g−1∙K−1. The Sommerfeld’s coefficient is maximum at T = 2/3 Tc where γ = 62.4 mJ ⋅mol−1 ⋅K−2 . It has also been observed, for the first time, that the thermodynamic quantities of YBCO123 are constant when temperature varies between 0 K and 18 K. Above 18 K, the thermodynamic quantities rise sharply. This observation has been attributed to the pairing of electrons in the singlet-s and singlet-p states.
Trend analysis of aerosol optical depth and angström exponent anomaly over East Africa
(scientific Research Publishing, 2017-10-31) Makokha, John Wanjala; Odhiambo, Jared Oloo; shem, Godfrey Juma
Trend analysis of atmospheric aerosols enhances confidence in the evaluation of both direct and indirect effects of aerosols on regional climate change. To comprehensively achieve this over East Africa, it’s important to understand aerosols temporal characteristics over well selected sites namely Nairobi (1˚S, 3 ˚E), Mbita (0˚S, 34˚E), Mau Forest (0.0˚S - 0.6˚S; 35.1˚E - 35.7˚E), Malindi (2˚S, 40˚E), Mount Kilimanjaro (3˚S, 37˚E) and Kampala (0˚N, 32.1˚E). In this context, trend analysis (annual (in Aerosol Optical Depth (AOD) at 550 nm and Angstrom Exponent Anomaly (AEA) at 470 - 660 nm) and seasonal (AOD)) from Moderate Resolution Imaging Spectroradiometer (MODIS) were performed following the weighted least squares (WLS) fitting method for the period 2000 to 2013. The MODIS AOD annual trends were ground-truthed by AErosol RObotic NETwork (AERONET) data. Tropical Rainfall Measurement Mission (TRMM) was utilized to derive rainfall rates (RR) in order to assess its influence on the observed aerosol temporal characteristics. The derived annual AOD trends utilizing MODIS and AERONET data were consistent with each other. However, monthly AOD and RR were found to be negatively correlated over Nairobi, Mbita, Mau forest complex and Malindi. There was no clear relationship between the two trends over Kampala and Mount Kilimanjaro, which may imply the role of aerosols in cloud modulation and hence RR received. Seasonality is evident between AOD and AEA annual trends as these quantities were observed to be modulated by RR. AOD was observed to decrease over East Africa except Nairobi during the study period as a result of RR during the study period. Unlike the other study sites, Nairobi shows positive trends in AOD that may be attributed to increasing populace and fossil fuel, vehicular-industrial emission and biomass and refuse burning during the study period. Negative trends over the rest of the study sites were associated to rain washout. The AOD and AEA derived annual trends were found to meet the statistical significance of 95% confidence level over each study site