Abstract: The quest for the design and synthesis of carbon dots with anti-counterfeit properties that are derived via green, environmentally friendly and economical procedures is a continuous process. Carbon dots (C-dots) derived from biowaste are cheap to synthesize, possess good photo-stabilityand high synthetic yield, making them applicable in the anti-counterfeiting of currency. Herein, we report a novel eco-friendly, cheaper, and faster method for the synthesis of carbon dots with stron...
Abstract: This study was conducted on the Ngaoundaba Crater Lake sediments to infer provenance, weathering conditions, organic matter accumulation, and trace metal concentrations. Ngaoundaba Lake sediments were collected using a manual core sampler at 5 to 8 m water depth. Two sediment cores from the littoral and center of the lake were analyzed for grain size distribution, water content (WC), organic matter content, mineralogy, and major and trace element concentrations. The Ngaoundaba sedi...
Abstract: The African mosquito species Anopheles gambiae and An. funestus are ranked high among the world's most efficient vectors of human malaria. Their juvenile stages develop in aquatic environments while adults are terrestrial. Chemical signals guide gravid females of these vectors to their egg-laying sites. Several attributes of a pond including presence of other organisms influence egg hatching success and larval survival. Gravid An. gambiae females strongly discriminate among potenti...
Abstract: This thesis describes the asymmetric phase-transfer catalysed (PTC) Darzens condensation of aldehydes and ketones with the chiral reagents 1-menthyl chloromethanesulphonate, (S)-(-)-N-chloromethylsulphony l-2 -thoxymethylpyrrolidine,(S)-(-)-tert-butyl N-(chloromethylsulphonyl)prolinate and (+)-0-methyl-N-(chloromethylsulphonyl)ephedrine using triethylbenzylammonium chloride (TEBA) as the phase-transfer catalyst.The chiral reagent 1-menthyl chloromethanesulphonate was obtained by th...
Abstract: Hexane, ethyl acetate and methanol extracts of Commiphora swynertonii Burtt., Turraea cormicopia (L), T abyssinica, T. floribunda and Melia volkensii Gurke were tested for anti-tick activity against the larvae and adult Rhipicephalus appendiculatus Neuman using the packet method bioassay. The hydrodistilled oil of the leaves of C. swynertonii was tested for acaricidal and repellency activities against ! adult R. appendiculatus using the packet and climbing bioassay method, respecti...
INTRODUCTION 1.1 Pheromones and related compounds It has long been known that animals communicate with each other. The communication becomes more important the more social the animal is. Even in microorganisms and plants communication seems important. For example, "biological communication" as broadly defined, 1 involves the release of one or more stimuli by an individual of a species to induce a reaction to the receiver and the benefit of such a reaction may be to the emitter, the receiver o...
Bush meat (Grass cutter) is one of the best natural meats with lots of nutritional advantages. The increase in consumption of bush meat serves as alternative which bridges the gap of the inadequacy of animal protein and other nutrition. The grass cutter (Thryonomys swinderianus) meat samples used in this research were collected from Emure Owo market, in Owo local government of Ondo state, Nigeria. The hairy skin of the fresh lifeless grass cutter was removed using hot water. The grass cutter ...
Bush meat (Grass cutter) is one of the best natural meats with lots of nutritional advantages. The increase in consumption of bush meat serves as alternative which bridges the gap of the inadequacy of animal protein and other nutrition. The grass cutter (Thryonomys swinderianus) meat samples used in this research were collected from Emure Owo market, in Owo local government of Ondo state, Nigeria. The hairy skin of the fresh lifeless grass cutter was removed using hot water. The grass cutter ...
Abstract: Maize is the main staple crop of most communities of the East African mountains but the yield is affected by both biotic and abiotic factors. While soil nutrients increase the maize yields, infestation of maize fields by Lepidopteran pests such as, Chilo partellus (Crambidae) and Busseola fusca (Noctuidae) generally reduces the yields. In addition to enhancing maize yields, some soil elements such as silicon (Si) aid plants in overcoming abiotic and biotic stresses. Hence, any fact...
Abstract: In this study, adsorption of heavy metals (copper, lead, zinc and cadmium) from aqueous solutions was investigated using mangrove biomass from the Kenyan Coast. The efficacy of mangrove biomass on the removal of divalent metal ions from aqueous solutions was investigated in single state in batch mode. Batch experiments involved the study of the effects of initial pH, temperature, initial concentration of the metal ion, adsorbent dosage and contact time on metal ions adsorption. The...
Abstract: The maize weevil, Sitophilus zeamais (Motchulsky), the lesser grain borer, Rhyzopertha dominica (Fabricius), and the Angoumois grain moth, Sitotroga cerealella (Oliver), are serious pests of stored grain in Kenya. The control of these insect pests relies heavily on the use of synthetic insecticides by better off farmers; but there is an increasing cost of application and erratic supply in developing countries. In addition, small-scale farmers cannot afford these commercial products...
Abstract: The adsorption of heavy metal ions (Cd2+), Cu2+), Pb2+) and Zn2+) by untreated water hyacinth Eichhornia crassipes obtained from Lake Victoria, Kenya was investigated under batch mode. A The effects of sample part, particle size, contact time, solution pH, and temperature, shaking speed, adsorbent dosage and initial metal ion concentration of aqueous solutions were investigated. The roots showed highest ability for the uptake of heavy metals (Cu, Zn, Cd and Pb) from aqueous solutio...
Abstract: Tomato is rated the second most important horticultural crop after potato in most parts of the world. However, its cultivation is threatened by infestations of Tuta absoluta (Lepidoptera: Gelechiidae). The pest originated from South America and is now invading fields and greenhouse production sites in the world. Tuta absoluta was first officially reported in Kenya in March 2014 at Isiolo and has spread to all parts where tomato is grown. The pest has been nicknamed tomato ‗Al–s...
ABSTRACT Ticks pose a major challenge and economic burden to livestock rearing as they inflict physical injury and transmit diseases resulting in heavy losses of livestock. Their control has relied mainly on the use of synthetic acaricides which are expensive and hazardous to the environment and non-target organisms. Intensive use of these acaricides has also resulted in tick resistance. Plant extracts could provide a viable alternative to tick control and management strategies. Calpurnia...
Table of Content List of Tables List of Schemes List of Figures Abstract Chapter One 1.1 General introduction 1.2 Malaria parasite 1.3 Malaria disease 1.4 Malaria vectors 1.5 Malaria control strategies 1.6 Significance of study 1.7 Hypothesis 1.8 Justification 1.9 Objectives of the Study Chapter Two: Literature Review 2.1 Uses of natural products in mosquito control 2.2 The Family Meliaceae 2.3 The Genius Turraea 2.4 Limonoids 2.5 Biosynthesis of limonoids Chapter Three: Experimental 3.1 G...