Browsing Faculty of Science by Issue Date
Now showing items 21-40 of 381
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Instruments for sustainable solid waste management in Botswana
(Sage http://wmr.sagepub.com/cgi/content/abstract/19/4/342, 2001)Sustainable solid waste management is a strategy for achieving environmental quality in both the developed and the developing world. Environmental quality is a necessary condition for an increase in per capita welfare over ... -
Human–computer interface design issues for a multi-cultural and multi-lingual English speaking country — Botswana
(Elsevier Science Ltd, www.elsevier.com/locate/intcom, 2001)This paper reports on research carried out to determine whether a localised interface is preferred by users in a multi-cultural and multi-lingual country where a non-local language is nationally used,. We attempted to ... -
Gaboroquinones A and B and 4'-O-demethylknipholone-4'-O-β-D-glucopyranoside, phenylanthraquinones from the roots of Bulbine frutescens
(American Chemical Society. http://pubs.acs.org/jnp/, 2002)The novel phenylanthraquinones 4'-O-demethylknipholone-4'-O-β-D-glucopyranoside (2) and gaboroquinones A (3) and B (4) were isolated from the African medicinal plant Bulbine frutescens. Biaryl 2 represents the first ... -
Origin and palaeo-environments of calcareous sediments' in the Moshaweng dry valley, Southeast Botswana
(John Wiley & Sons, Ltd. http://www3.interscience.wiley.com/journal/117935722/grouphome/home.html, 2002)Quaternary sedimentation in the Moshaweng dry valley of southeastern Botswana is evaluated on the basis of geomorphological evolution and sedimentological analyses. Stratigraphic evidence reveals an 'upper surface (1095 ... -
Stochastic models for sunshine duration and solar irradiation
(Elsevier Science Ltd: http://www.elsevier.com/wps/find/journaldescription.cws_home/969/description#description, 2002)Abstract Harmonic analysis of sunshine duration and solar irradiation measured at Sebele, Botswana is carried out. The data used consists of the monthly averages and the Julian-days averages of sunshine duration and solar ... -
Diterpenoids from the stem bark of Croton zambesicus
(Elsevier Science Ltd. www.elsevier.com/locate/phytochem, 2002)Three clerodane diterpenoids, crotozambefurans A, B and C were isolated from the stem bark of Croton zambesicus together with the known clerodane crotocorylifuran and two trachylobanes: 7b-acetoxytrachyloban-18-oic acid ... -
Homoisoflavonoids and xanthones from the tubers of wild and in vitro regenerated Ledebouria graminifolia and cytotoxic activities of some of the homoisoflavonoids
(Elsevier Ltd. www.elsevier.com/locate/phytochem, 2002)Eleven homoisoflavonoids and two xanthones were isolated and characterized from the bulbs of Ledebouria graminifolia. Five of the homoisoflavonoids are new compounds and were identified as: 5-hydroxy-7-methoxy-3-(40-hyd ... -
Dinklagins A, B and C: three prenylated flavonoids and other constituents from the twigs of Dorstenia dinklagei
(Elsevier Science Ltd. www.elsevier.com/locate/phytochem, 2002)Three prenylated flavonoids, dinklagins A, B and C identified, respectively, as ( )-6-(3,3-dimethylallyl)-7-hydroxy-6000, 6000-dimethylchromeno-( 40,30,2000,3000)-flavanone, (+)-5,40,500x-trihydroxy-600,600-dimethylchro ... -
The Free-Radical Copolymerization of Difurylmethane with Maleic anhydride
(South African Journal of Chemistry. <http://ejour.sabinet.co.za/images/ejour/chem/chem_v55_a1.pdf>., 2002)The copolymerization of difurylmethane with maleic anhydride in the presence of azobisisobutyronitrile as an initiator has been investigated at 65 °C, 72 °C and 85 °C in different solvents. Reaction feeds containing 85 ... -
Chalcones and other constituents of Dorstenia prorepens and Dorstenia zenkeri
(Elsevier Science Ltd. www.elsevier.com/locate/phytochem, 2002)The twigs of Dorstenia prorepens furnished the digeranylated chalcone, 5,30-(3,7-dimethyl-2,6-octadienyl)-3,4, 20,40-tetrahydroxychalcone while Dorstenia zenkeri yielded the 30,40-(3-hydroxy-2,2-dimethyldihydropyrano)-4 ... -
Gravity evidence for a larger Limpopo Belt in southern Africa and geodynamic implications
(Royal Astronomical Society. http://www.wiley.com/bw/journal.asp?ref=0956-540X&site=1, 2002)The Limpopo Belt of southern Africa is a Neoarchean orogenic belt located between two older Archean provinces, the Zimbabwe craton to the north and the Kaapvaal craton to the south. Previous studies considered the Limpopo ... -
Urban water scarcity management: civic vs. state response in Bulawayo
(Pergamon, www.elsevier.com/locate/habitatint, 2002)In most sub-Sahara African cities, rapid urbanization has placed a heavy burden on available human, financial and socioeconomic resources. The problem has been compounded by the intricate and interactive effects of rapid ... -
Energy sector policies in Botswana and their implications for global climate change
(Kluwer Academic Publishers, http://www.springerlink.com/content/102895/, 2002)Like most African countries, Botswana contributes almost insignificantly to global greenhouse emissions (GHGs). In this context, some have argued that energy policy and legislative measures to regulate emissions in Botswana ... -
Localized wood resource depletion in Botswana: Towards a demographic, institutional and cosmovisional explanation
(Taylor & Francis Ltd, http://www.tandf.co.uk/journals/cepe, 2002)In sub-Saharan Africa, communal land resource utilization and management has reflected changes in sociocultural belief systems, population dynamics, and modes of societal administration and regulation. This paper, based ... -
Antimicrobial Flavonoids from Bolusanthus speciosus
(Georg Thieme Verlag, https://www.thieme.com/, 2002)A new isoflavanone namely 3,5,7,2′,4′-pentahydroxy-8,3′-di(γ,γ-dimethylallyl)isoflavanone (bolusanthin II) and four new pterocarpans identified as 3-hydroxy-6′,6′-dimethylpyrano[2′,3′:1,2] [6aR,11aR]-8,9-methylenedioxypterocarpan ... -
Erythrinaline Alkaloids and Antimicrobial Flavonoids from Erythrina latissima
(Georg Thieme Verlag, https://www.thieme.com/books-main/biochemistry/product/3494-planta-medica, 2002)The seed pods of Erythrina latissima yielded erysotrine, erysodine, syringaresinol, vanillic acid, a new erythrina alkaloid, (+)-10,11-dioxoerysotrine, which was lethal to brine shrimp and 2-(5′-hydroxy-3′-methoxy ... -
Renewable energy education in Botswana: needs, status and proposed training programs
(Elsevier Science Ltd. http://www.sciencedirect.com/science/journal/09601481, 2002-01)Lack of trained manpower for repair and maintenance of solar energy devices in Botswana has resulted in failure of devices, loss of revenue, and dwindling of consumer faith in solar technologies. The government of Botswana ... -
Luminescence-laser classification of heteroaromatic and aromatic compounds
(Elsevier Science BV; www.elsevier.com/locate/saa, 2002-01-15)[Please note that the mathematical symbols have not transposed into this abstact].The luminescent and laser properties of heteroaromatic and aromatic compounds are reviewed and discussed on the basis of all possible mutual ... -
The theory of attenuated total reflection by surface polaritons on corrugated semi-infinite media
(Elsevier Science Ltd. www.elsevier.com/locate/physb, 2002-02)The experimental techniques of attenuated total reflection and grating-coupling were originally employed separately as probes for surface polaritons. However, as far back as the mid-1970s, some value was found in actually ... -
The current-induced critical field of a type II superconducting cylindrical filament
(Elsevier Science Ltd. www.elsevier.com/locate/physc, 2002-08-15)The azimuthal surface nucleation field of an infinitely long type II superconducting cylindrical filament is calculated from the linearized Ginzburg-Landau equation for the order parameter. A current is thought to be ...