Browsing Faculty of Science & Technology (FST) by Title

Now showing items 1594-1613 of 4283

    • The flatness problem as a natural cosmological phenomenon 

      Maumba, G O; Monyonko, N M; Malo, J O (University of NairobiDepartment of physics, 2008)
      An interplay between elementary particle interactions at very high energies and the expansion of the Universe is studied in the context of the inflationary model to find a possible explanation for an observed flatness ...

    • Flavanols from Tetrapleura tetraptera with cytotoxic activities 

      Ayoolu, Oguntimehin S; Ogbole, Omonike O; Ajaiyeoba, Edith O; Nchiozem-Ngnitedem, Vaderament-A; Demissie, Taye B; Elbadawi, Mohamed; Efferth, Thomas; Bedane, Kibrom G; Spitelle, Michael (University of Nairobi, 2022-05)
      Tetrapleura tetraptera is a medicinal plant used in East and West Africa to treat inflammation and related diseases. From the stem bark of the plant, three previously undescribed flavan-3-ol derivatives named (2R,3S)-3,3 ...

    • Flavone C-glycosides of Phoradendron tomentosum from different host trees 

      Dossaji, SF; Becker, H; Exner, J (Elsevier, 1983)
      Apigenin, three known apigenin C-glycosides, vitexin, schaftoside and isoschaftoside together with apigenin 4′-O-glucoside have been identified in leaves of Phoradendron tomentosum growing on different hosts.

    • Flavones and phenylpropenoids in the surface exudate of Psiadia punctulata 

      Jumaa Benard F.; Yenesew Abiy.; Midiwo Jacob O.; Waterman Peter G. (University of NairobiDepartment of Chemistry, University of Nairobi, 2001-06)
      Three flavones, 5,7-dihydroxy-2′,3′,4′,5′-tetramethoxyflavone, 5,4′-dihydroxy-7,2′,3′,5′-tetramethoxyflavone, and 5,7,4′-trihydroxy-2′,3′,5′ -trimethoxyflavone were isolated from the leaf exudate of Psiadia punctulata, ...

    • Flavonoids and isoflavonoids from Tephrosia fulvinervis and Tephrosia pentaphylla 

      Dagne, Ermias; Yenesew, Abiy; Waterman, Peter G (University of NairobiCollege of Biological and Physical Sciences, 1989)
      From the roots, leaves and pods of Tephrosia pentaphylla three new 6-oxygenated rotenoids (dihydrostemonal, 9-demethyldihydrostemonal and 6-acetoxydihydrostemonal) were isolated and characterized. In addition six known ...

    • Flavonoids and isoflavonoids of Erythrina burttii 

      Martin G. Peter.; Yenesew Abiy.; Heydenreich Matthias.; Guchu Salome M.; lrungu Beatrice.; Derese Solomon.; Midiwo Jacob O. (Department of Chemistry, University of Nairobi,lnstitut fur Chemie, Universitat Potsdam, 2009)
      From the stem bark and root bark of Erythrina burttii twenty-three flavonoids and isoflavonoids, including some eight new compounds, have been isolated and characterised. The stem bark of this plant mainly produces isoflavanones ...

    • Flavonoids and Isoflavonoids with Antiplasmodial Activities from the Root Bark of Erythrina abyssinica 

      Yenesew Abiy.; Derese Solomon.; Irungu Beatrice.; Midiwo Jacob O.; Waters Norman C.; Liyala Pamela.; Akala Hoseah.; Heydenreich Matthias.; Peter Martin G. (University of NairobiDepartment of Chemistry, University of Nairobi, 2003-07)
      From the root bark of Erythrina abyssinica a new pterocarpene [3-hydroxy-9-methoxy-10-(3,3-dimethylallyl)pterocarpene] and a new isoflav-3-ene [7,4′-dihydroxy-2′,5′-dimethoxyisoflav-3-ene] were isolated. In addition, the ...

    • Flavonoids from Tephrosia aequilata 

      Tarus, Paul K.; Machocho, Alex K.; . Lang'at-Thoruwa, Caroline C; . Chhabra, Sumesh C (University of Nairobi, 2002-06)
      From the roots of the plant Tephrosia aequilata Baker, five flavonoids were isolated of which, 3,4:8,9-dimethylenedioxypterocarpan is reported for the first time. Its structure and those of the already known flavonoids ...

    • Flavonoids from Tephrosia interrupta and tephrosia linearis". Fitoterapia, LXI,372 

      Prof.Munavu, Raphael M (University of NairobiCollege of biological and physical science, 1990)

    • Flavonoids from the bark of Erythrina burttii and Erythrina sacleuxii 

      Yenesew, A (University of NairobiDepartment of Chemestry, 1997)

    • Flavonoids from the seed pods of Tephrosia pumila 

      Yenesew, Abiy; Dagne, Ermias; Waterman, Peter G (University of NairobiDepartment of Chemistry, Addis Ababa UniversityPhytochemistry Research Laboratories, Department of Pharmacy (Pharm. Chem.), University of StrathclydeCollege of Biological and Physical Sciences,University of Nairobi, 1989)
      Inaddition to the known pumilaisoflavones A and B two further isoflavonoids have been isolated from the seed pods of Tephrosia pumila collected in Ethiopia. These have been characterized, on the basis of spectral analysis, ...

    • Flavonoids of polygonum senegalense (MEISN) part II: More surface and internal tissue flavonoid aglycones 

      Midiwo, J Ogweno; Gikonyo, NK; Wanjau, DO; Matasi, JJ; Waterman, PG (Department of Chemistry, 1992)

    • Flavonoids of the roots and stem bark of erythrina burttii and erythrina abyssinica 

      Midiwo, J. O.; Derese, S.; Yenesew, A. (Department of Chemistry, University of Nairobi,, 2011)
      The genus Erythrina belongs to the subfamily paplinoideae of the family Leguninosae. This genus is widely distributed in tropical and subtropical regions of the world and is represented by 125-200 species. The presence ...

    • A flavonol glycoside from Myrsine africana leaves 

      Manguro, Lawrence O; Midiwo, Jacob Ogweno; Kraus, Wolfgang (College of Physical and Biological Sciences, 1996)
      Myricetin 3-(3″,4″-diacetylrhamnoside), a novel flavonol glycoside together with myricetin 3-rhamnoside, myricetin 7-rhamnoside, myricetin 3-xyloside, myricetin 3-arabinoside, quercetin 3-galactoside, 3′-O-methylquercetin ...

    • Flemingins G–O, Cytotoxic and Antioxidant Constituents of the Leaves of Flemingia grahamiana 

      Erdelyi, Mate; Yenesew, Abiy; Sunnerhagen, Per; Ndiege, Isaiah O; Alao, John P; Gumula, Ivan (2014)
      The known flemingins A–C (1–3) and nine new chalcones, named flemingins G–O (4–12), along with deoxyhomoflemingin (13) and emodin (14) were isolated from a leaf extract of Flemingia grahamiana. The isolated chalcones were ...

    • Flood Forecasting Over Lower Nzoia Sub-basin In Kenya 

      Ngaina, Joshua N; Mwaura, Njoroge James; Mutua, Francis; Kipkoech, Mutai Bethwel; Opere, Alfred Owuor (University of Nairobi, 2014)
      Real time flood forecasting is one of the most effective non- structural measures for flood management. In this study, Ensemble Kalman Filter (EnKF) is used with Probability Distributed Moisture model (PDM) to forecast ...

    • Flood frequency analysis in lake Victoria basin based on tail behaviour of distributions 

      Ndetei, CJ; Opere Alfred O.; Mutua, FM (University of NairobiDepartment of Meteorology, 2007)
      The primary objective of the study was to find a suitable distribution class for flood frequency analysis on the Kenyan side of Lake Victoria basin. This involved performing at-site analysis using Peak Over Thresh-old ...

    • Flow of a Viscous Incompressible Fluid Along an Impulsively started Infinite Plate with constant suction 

      Singh, CB; Pandey, KS; Chaturvedi, N (University of Nairobi.School of Mathematics, 1979-06)

    • Flow of electric currents of telluric origin in a long metal pipeline and their effect in relation to corrosion control 

      Skinner, N J; Barker, R H (1980)
      To determine the effects of telluric currents on the corrosion of a 280-mile (450-km) steel pipeline in Kenya, Spencer and Partners, London, and the University of Nairobi, Kenya, estimated the extent to which these currents ...

    • Flow routing in river Yala using the Muskingum technique (revised) 

      Opere, A. O; Owiti, Z. O (2007)
      Changes in hydrological regimes affect the socio-economic set up in a river basin. Understanding the availability and temporal characteristics of water in river systems can help in monitoring changes in a hydrologic regime. ...