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Now showing items 21-40 of 15021
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Reactions of Lead Tetraacetate. II. Formation of Carbamic Acid Esters from Primary Carboxamides
(CSIRO Publishing, 1968)Treatment of primary carboxamides with lead tetraacetate in benzene-alcohol mixtures or neat alcohol affords a convenient, flexible, and efficient method for the preparation of N-substituted carbamic acid esters. The ... -
Reactions of Lead Tetraacetate. I. Formation of Acylamines from Primary Carboxamides
(CSIRO Publishing, 1968)Pentanamide, when treated with lead tetraacetate in hot benzene, affords a mixture of N-butylacetamide and N,N?-dibutylurea. Examples of similar transformations of a number of primary carboxamides are described. The reaction, ... -
The Structure and Synthesis of Barakol: a Novel Dioxaphenalene Derivative from Cassia siamea
(Royal Society of Chemistry, 1970)Barakol, from the leaves of Cassia siamea, is shown to be a novel dioxaphenalene derivative. A synthesis from 3,5-dihydroxyphenylacetic acid is described. -
Correlation of melting temperature and cesium chloride buoyant density of bacterial deoxyribonucleic acid.
(American Society for Microbiology, 1970)Samples of bacterial deoxyribonucleic acid from bacteria having guanine plus cytosine (GC) contents in the range of 27 to 72 moles per cent GC were analyzed by optical melting (T(m)) and equilibrium buoyant density methods. ... -
The method of the false transient for the solution of coupled elliptic equations
(Elsevier, 1973-08-04)A method for the numerical solution of a system of coupled, nonlinear elliptic partial differential equations is described, and the application of the method to the equations governing steady, laminar natural convection ... -
Land, labour and capital in Natal: The Natal Land and Colonisation Company 1860–19481
(Cambridge University Press, 1975-04)The history of the London-based Natal Land and Colonisation Company is explored against the background of the evolving political economy of rural Natal. In the early years of the colony, white-controlled farming operations ... -
Some effects of mound-building termites on soils in Uganda
(Bioinfo Publications, 1976-09)Most large mounds in Uganda are built by termites of the genus Macrotermes. Except for those in valley bottoms they are composed of subsoil which is thought to be collected mainly from depths of 0.5 to 1.0 m, although the ... -
Histological observations on the changes in thyroid activity in the scincid lizard, Mabuya striata, during different phases of tail regeneration
(Zoological Society of Southern Africa, 1977)Measurements of the follicle cells of the thyroid during different phases of regeneration of the tail in the scincid lizard. Mabuya striata. indicate a decrease in thyroid activity during the wound-healing phase and an ... -
Effects of temperature on growth in the regenerating tail of the scincid lizard, Mabuya striata
(Zoological Society of Southern Africa, 1977)Experiments on effects of temperature on growth in the regenerating tail of Mabuya striata, artificially autotomized, suggest a faster rate of regeneration during hot weather than cold weather. limbs of newts and ... -
Reaction of some arylacetic acids and related compounds with alkaline sodium hypochlorite solution
(Royal Society of Chemistry, 1978) -
Pea Aphid: Interaction of Insecticides and Alfalfa Varieties
(Entomological Society of America, 1978-02)Carbofuran, methoxychlor, Mobile MCA-600 (benzo [b]thien-4-yl methylcarbamate), leptophos, methidathion, and dialifor were evaluated for control of Acyrthosiphon pisum (Harris) on the alfalfa varieties `Cody', `Dawson',` ... -
Reproductive Biology of Tilapia zillii (Gervais) in Lake Naivasha, Kenya
(Kluwer Academic Publishers, 1979)Tilapia zillii breeds all year round in the equatorial Lake Naivasha with slightly high breeding intensity during wet months (March, May and July–August). A sex ratio of 1 : 1.28 was found between males and females. The ... -
Emergence of Advance Waves in a Steady-state Universe
(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 ... -
Changes in Fish Species Composition in Lake Naivasha, Kenya
(Kluwer Academic Publishers, 1979)The fish species composition in Lake Naivasha has been modified during recent years. Out of seven introduced and one indigenous species reported in 1962, only three introduced ones are found today. The elimination of species ... -
Short Essays on Education in Kenya
(Kenya Literature Bureau, 1980)The essays deal with a wide range of subjects and discuss a number of problems in Kenyan education in depth. Subjects include: problems of policy in African education in the colonial days, highlighting the Christian ... -
Synthesis, Spectral and Structural Studies, and an Evaluation of the Hydrogen Bonding of Some Phenylhydrazone
(Royal Society of Chemistry, 1980)A series of 46 phenylhydrazones, soms novel, containing a variety of structural types has been synthesised. These have been studied by lH n.m.r. and i.r. spectroscopy with respect to potential inter- and intra-mslecular ... -
The inhibition of germination of bidens pilosa seeds by leaf canopy shade in some natural vegetation types
(Wiley, 1980-01)The inhibition of germination by leaf canopies was investigated in Bidens pilosa, a widespread tropical colonizing weed species. Seeds of this species were sown in the shade of four natural vegetation types: early colonizing ... -
The induction of a light requirement in bidens pilosa seeds by leaf canopy shade
(Wiley, 1980-01)The aim of these experiments was to determine whether exposure to leaf-canopy shade induces a light requirement for germination in Bidens pilosa seeds. Seeds of this species were pretreated by placing them in the shade ... -
Control of the potato tuber moth (Phthorimaea operculella) (zell) in storage using dust formulated insecticides.
(Ministry of Agriculture, 1980-01)Tubers of potato variety Roslin Gucha were dusted with the followign insecticides:- Pirimiphosmethyl (1 percent, permethrin (1 percent) cypermethrin (0.5 percent), Fenvalarate (1 percent) and etrimfos. The adult moths were ... -
Germination tests on thirty-two East African weed species
(Wiley, 1980-06)The seeds of thirty-two species of common East African weeds were set to germinate in the light and in the dark. Eighteen species with more than 40% germination in the light were also germinated in leaf shade and in neutural ...
