Browsing Faculty of Science by Issue Date
Now showing items 41-60 of 381
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The P wavespeed structure below and around the Kaapvaal craton to depths of 800 km, from traveltimes and waveforms of local and regional earthquakes and mining-induced tremors
(Oxford University Press, https://academic.oup.com/gji, 2002-10-01)An average P-wavespeed model from the surface to depths of 800 km was derived for southern Africa using traveltimes and waveforms from earthquakes recorded at stations of the Kaapvaal and South African National networks. ... -
Mantle structure and composition to 800-km depth beneath southern Africa and surrounding oceans from broadband body waves
(Elsevier Science Ltd. www.elsevier.com/locate/lithos, 2003)Average one-dimensional P and S wavespeed models from the surface to depths of 800 km were derived for the southern African region using travel times and waveforms from earthquakes recorded at stations of the Kaapvaal and ... -
Pn arrivals and lateral variations of Moho geometry beneath the Kaapvaal craton
(Elsevier Science Ltd. www.elsevier.com/locate/lithos, 2003)Pn arrivals from mining-induced earthquakes on the edge of the Witwatersrand basin show that the P wavespeeds in the uppermost mantle are almost constant throughout most of the Kaapvaal craton. The presence of only small ... -
Optimising growth conditions for the pectinolytic activity of Kluyveromyces wickerhamii by using response surface methodology
(Elsevier / www.elsevier.com/locate/ijfoodmicro, 2003)This present study was undertaken to find optimum conditions of pH, temperature and, period of incubation for the pectinolytic activity of Kluyveromyces wickerhamii isolated from rotting fruits and to assess the effect ... -
The influence of the Tbetta level upon fluorescence and laser properties of aromatic compounds
(Elsevier Science Ltd http:www.elsevier.com/locate/saa, 2003)Please refer to the attached article for an ABSTRACT. The abstract was not uploaded here due to formula appearance problem in UBRISA. -
Comprehensive study of solar conditions in Mozambique: the effect of trade winds on solar components
(Elsevier Science Ltd. www.elsevier.com/locate/renene, 2003)A new algorithm to simulate all solar components and optimum slopes, Bopt, based on new models for direct normal beam and diffuse radiation and an analytical model to predict Bopt, developed at the University of Botswana ... -
Influence of weak and strong donor groups on the fluorescence parameters and the intersystem crossing rate constant
(Elsevier Science Ltd. www.elsevier.com/locate/saa, 2003)Please refer to the attached article for an ABSTRACT. The abstract was not uploaded here due to formula appearance problem in UBRISA. -
Bivarate models: relationships between solar irradiation and either sunshine duration or extremum temperatures
(Elsevier Science Ltd. www.elsevier.com/locate/renene, 2003)The Republic of Botswana is one of the sunniest countries in Southern Africa. It has very little cloud cover, insufficient rainfall, very low humidity, and very low wind speed throughout the year for most parts of the ... -
Antioxidant activity of prenylated flavonoids from the West African medicinal plant Dorstenia mannii
(Elsevier Science Ireland Ltd. www.elsevier.com/locate/jethpharm, 2003)The antioxidant activities of three prenylated flavonoids from Dorstenia mannii (6,8-diprenyleriodictyol, dorsmanin C and dorsmanin F) were compared to the common, non-prenylated flavonoid, quercetin. The prenylated ... -
Phenylpropanoid glycosides of Gnidia polycephala
(Elsevier Ltd. www.elsevier.com/locate/phytochem, 2003)Two phenylpropanoid glucosides, 2-O-b-d-glucosyloxy-4-methoxybenzenepropanoic acid and its methyl ester, together with syringin and adicardin were isolated from the stem of Gnidia polycephala and characterized by physical ... -
Influence of seasonal flooding on soil total nitrogen, organic phosphorus and microbial populations in the Okavango Delta, Botswana
(Journal of Arid Environments. http://www.elsevier.com/wps/find/journaldescription.cws_home/622855/description#description, 2003)The effect of flooding on soil total nitrogen, phosphorus and microbial population in different vegetation zones (floodplain, island and woodland) and profile depth (0?1, 0?5, 2?0, 3?0, 4?0 and 5?0m) of the Okavango ... -
Building computer graphics education in southern Africa
(Elsevier Science Ltd, http://www.elsevier.com/locate/cag, 2003)This note discusses issues in building the educational base for computer graphics growth in developing countries, particularly in southern Africa. It is based on a delegation’s visit to southern Africa in the spring of ... -
Prenylated flavonoids, monoterpenoid furanocoumarins and other constituents from the twigs of Dorstenia elliptica (Moraceae)
(Elsevier Ltd. www.elsevier.com/locate/phytochem, 2003)A monoprenylated flavan and two monoterpenoid substituted furanocoumarins were isolated from the twigs of Dorstenia elliptica along with 3-(3,3-dimethylallyl)-4,20,40-trihydroxylchalcone, psoralen, bergapten, O-[3-(2,2- ... -
South African seismicity, April 1997 to April 1999, and regional variations in the crust and uppermost mantle of the Kaapvaal craton
(Elsevier Science Ltd. www.elsevier.com/locate/lithos, 2003)Events induced by deep gold-mining activity on the edge of the Witwatersrand basin dominate the seismicity of South Africa. The deployment of 54 broad-band seismic stations at 84 separate locations across southern Africa ... -
Environmental change and sustainability issues in the Kalahari region
(Elsevier Science Ltd, http://www.elsevier.com/wps/find/journaldescription.cws_home/622855/description#description, 2003)The collection of papers in this special edition of the Journal of Arid Environments is a sequel to a Workshop held in Maun, Botswana, in October 2000, on the theme Climate Change, Biodiversity and Multi-species Production ... -
Diprenylated chalcones and other constituents from the twigs of Dorstenia barteri var. subtriangularis
(Elsevier Ltd; www.elsevier.com/locate/phytochem, 2003)The twigs of Dorstenia barteri var. subtriangularis yielded three diprenylated chalcones: ( )-3-(3,3-dimethylallyl)-50-(2-hydroxy-3- methylbut-3-enyl)-4,20,40-trihydroxychalcone, (+)-3-(3,3-dimethylallyl)-40,50-[2000-(1 ... -
Fluorescence and laser properties of D2-, C2- and D3 symmetry series oligophenylenes
(Elsevier Science Ltd. www.elsevier.com/locate/saa, 2003) -
Resource use conflicts: the future of the Kalahari ecosystem
(Elsevier http://www.linkinghub.elsevier.com/retrieve/pii/S0140196302910992, 2003)The Kalahari ecosystem is characterized by natural resource conflicts and land-use pressure resulting from intensification of human activities. This paper addresses three issues of concern associated with the Kalahari ecosystem ... -
Major and trace element geochemistry of plutonic rocks from Francistown, NE Botswana: evidence for a Neoarchaean continental active margin in the Zimbabwe craton
(Elsevier www.elsevier.com/locate/lithos, 2003)The Neoarchaean Tati granite–greenstone terrane occurs within the southwestern part of the Zimbabwe craton in NE Botswana. It comprises 10 intrusive bodies forming part of three distinct plutonic suites: (1) an earlier ... -
Population, development, and waste management in Botswana: Conceptual and policy implications for climate change
(Springer http://www.springerlink.com/index/3NU5AFH2F999FM9P.pdf -, 2003)Based on government and other relevant documentation, this paper explores the conceptual linkage between population, development, and waste management in Botswana and the implications of this relationship for global climate ...