Now showing items 1-20 of 98

    • Lead contamination of traditional hand-dug wells in parts of Kwale County, Kenya 

      Chege, M. W.; Hashim, N. O.; Merenga, Abdullah S.; Tschiersch, J. (International Journal of Physical Sciences, 201-05)
      People’s health, behavior and intellect to a certain extent are a function of their environment. One important component of this environment is water, a basic necessity that human beings cannot do without. The water ...
    • Beta-gamma-gamma directional correlation in103Rh 

      Rathore, I. V. S.; Singh, B P (Pramana, 1977)
      β-γ-γ directional correlation studies for the cascades (i)β-rays ofE max=0.12 MeV,γ-rays of 557 keV andγ-rays of 53 keV and (ii)β-rays ofE max=0.21 MeV,γ-rays of 444 keV andγ-rays of 53 keV have been made. The triple ...
    • Emergence of Advance Waves in a Steady-state Universe 

      Hobart, R. H. (Kluwer Academic Publishers, 1979)
      In standard Wheeler-Feynman electrodynamics advanced waves from any source are absolutely canceled by the advanced waves from the absorber responding to that source. The present work shows this cancellation fails over ...
    • Solar wind controlled pulsations: A review 

      Odera, T. J. (Reviews of Geophysics, 1986-02)
      Abstract Studies of the solar wind controlled Pc 3, 4 pulsations by early and recent researchers are highlighted. The review focuses on the recent observations, which cover the time during the International Magnetospheric ...
    • PC 3,4 magnetic pulsations observed simultaneously in the magnetosphere and at multiple ground stations 

      Odera, T.J.; Swol, D.V.; Russell, C.T.; Green, C.A. (Reviews of Geophysics, 1991-09)
      Periods of magnetic conjugacy between ISEE and the magnetometer array of the Institute for Geological Sciences have been examined to search for the simultaneous occurrence of Pc 3,4 magnetic pulsations. When compressional ...
    • Electrons, holes, and the hall effect in amorphous silicon 

      Okumu, John; Morgan, G.J.; Holender, J. M.; Weaire, D.; Hobbs, D. (Elsevier, 1993-12-02)
      The double sign anomaly in hydrogenated amorphous silicon, observed by LeComber et.al.in 1977, has remained puzzling ever since. Recently we attacked this problem from two different directions using the equation-of-motion ...
    • The Hall effect and electronic conduction in amorphous Si 

      Okumu, John; Holender, J. M.; Morgan, G. J. (Taylor &Francis, 1995-02-17)
      We show that the random-phase model for the electronic wavefunctions gives very reasonable agreement with recent computations of the conductivity for amorphous Si. Furthermore the model also yields the double-sign anomaly ...
    • A Preliminary Study of Relative Permeability in Geothermal Rocks Authors 

      Ambusso, W.; Satik, C.; Castanier, L.M.; Horne, R.N. (Geothermal Resources Council, Davis, CA (United States), 1995-12-31)
      This paper reports preliminary experimental and numerical efforts towards obtaining steam-water relative, permeability and capillary pressure functions under steady-state and adiabatic conditions. In the experimental ...
    • Determination of Relative Permeability for Steam-Water Flow in Porous Media 

      Ambusso, W.; Satik, C.; Horne, R.N. (Society of Petroleum Engineers, 1996-01-01)
      A set of relative permeability relations for simultaneous flow of steam and water in porous media were obtained from a steady state experiment. The experiment was conducted under conditions that minimize most of the ...
    • Alkaloids from Crinum kirkii 

      Bastida, J.; Codina, C.; Peeters, P.; Rubiralta, M.; Orozco, M.; Luque, F.J.; Chhabra, S. C. (Wiley Online Library, 1996-03)
      ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please ...
    • Analysis of Soil for Trace Elements along Two Highways of Kenya 

      Hashim, N.O.; Kinyua, A. M.; Mangala, M. J.; Rathore, I. V. S. (Faculty of Science Kenyatta University, 1998)
      Energy dispersive X-ray fluorescence technique has been used to study the levels of lead and other toxic trace elements in the soil samples collected along two major highways (Mombasa and Thika) of Kenya at the various ...
    • A generalized Coulomb-projected Born Calculation using Screened Coulomb Potential 

      Singh, C. S. (Faculty of Science Kenyatta University, 1998)
      The Coulomb-projected Born method proposed by Geltman has been generalized by using the screened Coulomb potential of the form in place of the nuclear potential experienced by the incident electron. The results obtained ...
    • Ohmic and Space-Charge-Limited Conduction in Doped Amorphous Arsenic Triselenide 

      Wafula, A. B. (Faculty of Science Kenyatta University, 1998)
      The electrical characteristics of asernic triselenide have been studied. A number of parameters is evaluated on the basis of the theory of space-charge limited conduction and the following values were obtained: hole ...
    • Steam - Water Relative Permeability 

      Ambusso, Willis Jakanyango; Horne, R. N.; Satik, C.; Mahiya, G.; Li, K.; Tovar, R.; Wang, C.; Nassori, H. (2000)
      Reliable measurement of steam-water relative permeability functions is of great importance for geothermal reservoir performance simulation. Despite their importance, these functions are poorly known due to the lack of ...
    • Optical studies of doped amorphous arsenic triselenide 

      Wafula, A.B.; Dod, T.S. (Faculty of Science Kenyatta University, 2000)
      Photoconductivity of As2Se3:Alx and As2Se3:Cux was investigated using light of visible spectrum of wavelengths A. = 0.67 um & 0.47 urn. Two regimes were observed: regime 1, the high temperature region above maximum ...
    • Physical properties of thin GeO2 films produced by reactive DC magnetron sputtering 

      Njoroge, W. K.; Lange, T.; Weis, H.; Beckers, M.; Wuttig, M. (Elsevier, 2000-04-03)
      We have studied optical and structural properties of GeOx films produced by reactive DC magnetron sputtering of Ge targets in an Ar/O2-mixture. Optical spectroscopy measurements of reflectance and transmittance of the films ...
    • Steam-Water Relative Permeability 

      Ambusso, W.; Horne, R.N.; Satik, C.; Mahiya, G.; Li, K.; Tovar, R.; Wang, C.; Nassori, H. (Davis, CA; The Geothermal Resources Council, 2000-05-28)
      A set of relative permeability relations for simultaneous ow of steam and water in porous media have been derived from experiments conducted under conditions that eliminate most errors associated with saturation and ...
    • Calculation of linear and non-linear optical properties of amorphous Silicon 

      Okumu, J.; Morgan, G.J. (Faculty of Science Kenyatta University, 2001)
      We have used the random phase model for the electronic wave functions to calculate the imaginary part of the dielectric function 82 (m) and the magnitude of the third harmonic generation, 11'3(OJ ~ using a model structure ...
    • Mechanical stresses upon crystallization in phase change materials 

      Njoroge, W. K.; Kalb, J.; Wamwangi, D.; Wuttig, M.; Spaepen, F. (American Institute of Physics, 2001)
      Crystallization processes in different Te alloys, employed in phase change materials for optical data storage, have been investigated by in situ mechanical stress measurements. Upon crystallization a considerable stress ...
    • Structural and optical properties of thin lead oxide films produced by reactive direct current magnetron sputtering 

      Njoroge, W. K.; Venkataraj, S.; Geurts, J.; Weis, H.; Kappertz, O.; Jayavel, R.; Wuttig, M. (American Vacuum Society, 2001)
      The structural and optical properties of thin lead oxide films were studied. Thin films were prepared by reactive dc magnetron sputtering of lead(Pb) targets in an Ar/O2 mixture. The structure has been determined by x-ray ...