Abstract: The wastewater treatment industry has identified the discharge of inorganic anions such as phosphate and fluoride into water as a risk to the natural environment and human health. Among various methods used to remove phosphate and fluoride anions, adsorption is widely used because of its low cost, ease of use and simplicity. In this study, cerium-based organic metal frameworks was proposed as adsorbent to remove phosphate and fluoride ions from water.. The aim of this work was to s...
Abstract: Correct identification of misconception is an important first step in order to gain an understanding of student learning. More recently, four- tire multiple choice test have been found to be effective in assessing students ’alternative conception. The purpose of this study was using a four tier test to assess and identify students’ alternative conceptions about chemical thermodynamics concepts. The study was carried out at two preparatory schools of Babile Woreda (Babile and Bi...
Abstract: Eucalyptus globulus is one of the abundant tree species in Ethiopia known for medicinal values of its essential oils. The essential oil composition of a given species may vary with environmental factors. In this study, leaf of essential oil compositions and their antimicrobial activities were analyzed from E. globulus sampled from Haramaya University (HU) and Entoto Park (EP). Essential oils were extracted by steam distillation method and their compositions were analyzed using GC. ...
Abstract: Fermentation is a metabolic process of microorganisms to obtain energy by breaking down organic compound. Sorghum straw was fermented with different concentration substrate (15gm, 30gm , 45g and 60gm) with 0.5% ,1% yeast in different fermentation period (4th day, 8th day, 12th and 16th days) with the aim of ethanol production from Sorghum straw. Among the different substrate concentration 15 gram of substrate mixed with 1% yeast produced high quantity of ethanol on 4th day of ferme...
Abstract: Irish Potato (Solanum tuberosum L.) is one of the world’s most economically important tuber crops belonging to the family Solanaceae. It is a versatile vegetable that is eaten all around the year. The objective of this study was to establish a protocol for in vitro micropropagation of Gudene and Belete Irish potato varieties from lateral bud explants. For shoot induction lateral buds of Gudene and Belete were cultured on MS basal medium that contained 30 g/l sucrose, 6 g/l agar, ...
Abstract: Papaya (C. papaya) is a medicinal plant due to its specific enzymes and bioactive compounds. Besides its nutritional properties, leaves and seeds are the most useful part among all used parts for the medicinal purpose. The present study is undertaken to investigate phytochemical screening, antioxidant and antimicrobial activities of aqueous and methanol extracts of papaya leaf and seed. The qualitative screening of phytochemicals was conducted using water and methanol as solvents. ...
Abstract: The emergence of increased multidrug resistant bacteria has initiated development of new antimicrobial agents. Essential oils from aromatic plants and herbal extracts have attracted scientific interest due to their potential use as antimicrobial and/or antioxidant compounds in foods.The present study was aimed to examine physicochemical properties and biological activities of essential oils extracted from sweet basil leaves and infloresence Evaluation of the Physicochemical propert...
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...
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...