Faculty of Science: Recent submissions
Now showing items 361-380 of 381
-
Work in Thermodynamics
(Chemic Publishing Co., http://www.asianjournalofchemistry.com/, 2006)The expression for mechanical work obtained in the expansion of a gas commonly used in physical chemistry textbooks is critically examined. The mathematical form of the first law of thermodynamics is arrived at by a procedure ... -
Antibacterial Diterpenes from the Roots of Ceriops tagal
(Natural Product Inc. http://www.naturalproduct.us/, 2008)Investigation of the roots of Ceriops tagal led to the isolation of a new isopimarane, together with the known diterpenes isopimar-8(14)-en-15,16-diol and erythroxyl-4(17),15(16)-dien-3-one. The structure of the new ... -
Antimicrobial and radical scavenging flavonoids from the stem wood of Erythrina latissima
(Elsevier Ltd; http://www.elsevier.com/wps/find/journaldescription.cws_home/273/description, 2004-11-20)From the stem wood of Erythrina latissima, two isoflavones and a flavanone were isolated and characterized as 7,3'-dihydroxy-4'-methoxy-5'-(y,y-dimethylallyl)isoflavone (erylatissin A), 7,3'-dihydroxy-6".6"-dimethyl-4".5 ... -
Evaluation of methods for the isolation, detection and quantification of cyanobacterial hepatotoxins
(Elsevier Ltd. http://www.elsevier.com/wps/find/journaldescription.cws_home/505509/description#description, 2006)Cyanobacterial hepatotoxins such as microcystins and nodularins have been responsible for the poisoning of both animals and humans who ingest or come into contact with toxic blooms. They are extremely stable in water due ... -
Type II superconducting disk in a spatially inhomogeneous applied magnetic field
(Elsevier Science Ltd. www.elsevier.com/locate/physc, 2003-01)The problem of a type II superconducting disk in a spatially inhomogeneous magnetic field is considered. The aim of the investigations undertaken here is to evaluate the effects of the spatial inhomogeneity of the parallel ... -
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 ... -
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 ... -
Inhibitory response of Raphanus sativus on lipid peroxidation in albino rats
(Oxford University Press, Oxford Journals; http://ecam.oxfordjournals.org/, 2008-03)In the present study, inhibitory effect of the methanol extract of Raphanus sativus root on lipid peroxidation has been carried out in normal rats. Graded doses of methanol extract of root of the plant (40, 80 and 120 ... -
Effects of different types of water decoctions of fruit of Melia azedarach on glucose induced hyperglycemia, liver transaminases, lipid peroxidation and reduced glutathione in normal albino rats
(Academic Journals http://www.academicjournals.org/SRE/index.htm, 2007)Four types of extracts were prepared from Melia azedarach fruits. These were methanol extract and three types of water decoctions; urine treated water decoction (UE), milk treated water decoction (ME) and plain water ... -
Homotopy Lie Algebra of Spaces for Hyperbolic Coformal 2-Cones
(International Press; http://www.intlpress.com/HHA/, 2004)In this paper, we show that the rational homotopy Lie algebra of classifying spaces for certain types of hyperbolic coformal 2-cones is not nilpotent. -
Improved particle swarm algorithms for global optimization
(Elsevier Ltd. www.elevier.com/locate/amc, 2008)Particle swarm optimization algorithm has recently gained much attention in the global optimization research community. As a result, a few variants of the algorithm have been suggested. In this paper, we study the efficiency ... -
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 ... -
Photochromism, anomalous multi-banded fluorescence and laser properties of some amino- and tosyl-amino derivative of oxadiazole
(Elsevier Ltd. www.elsevier.com/locate/saa, 2006)The multi-banded fluorescence and laser properties of 11 new amino- and tosylamino derivatives of 2,5-di(phenyl)-1,3,4-oxadiazole and oxadiazole in various solvents at 293 K are reported. All the compounds investigated ... -
String Homology of a Product of Spheres and the Witt Algebra
(Nova Science Publishers, Inc.; www.novapublishers.com; reprinted with permission from Nova Science Publishers, Inc., 2007)Let X be a finite product of even dimensional spheres, we show that the string homology of X contains a finite product of copies of the Witt Lie algebra. -
Trace enrichment of metal ions in aquatic environments by Saccharomyces cerevisiae
(Elsevier; www.elsevier.com/locate/talanta, 2004)[Please note that chemical formulae do not display correctly in this abstract]. Sorption properties of baker's yeast cells, characterised as Saccharomyces cerevisiae were evaluated for trace enrichment of metal ions: Cd2+, ... -
Investigation of sustainability of rain-fed agriculture through soil moisture modeling in the Pandamatenga Plains of Botswana
(Elsevier Ltd. http://www.elsevier.com/wps/find/journaldescription.cws_home/413/description#description, 2006)The agricultural economic sector of Botswana is limited mainly to range resources-based livestock and pockets of arable farming based on rainfall and limited irrigated agriculture at several places. In this study agricultural ... -
Deltamethrin in sediment samples of the Okavango Delta, Botswana
(Water SA Pretoria; Water Research Commission; http://www.wrc.org.za/, 2006-10)Deltamethrin concentrations were determined in 35 sediment samples collected from three different habitats: channel, lagoon and pool sites from Xakanaxa in the Okavango Delta, NW Botswana. The samples were Soxhlet-extracted ... -
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 ... -
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 ...