Electrical Resistivity Survey on Two Waste Dumpsites at Nguru, Potiskum, Yobe State, Nigeria to Determine the Effect of Leachates on Ground Water Aquifer

The research intends to bring out the contribution of leachate on groundwater in two dumpsites in Nguru and Potiskum all in Yobe state, Nigeria. A total of seven (7) and eight (8) VES by Schlumberger electrode with the use of Wenner electrode configuration. The results were interpreted by the use of WinRESIST for VES and IPWIN2INV for ERT. The study pointed out that, the area in question is comprised of four layers of geoelectric such as the topsoil, clay, sand, sandy clay and sand. The range of the first resistivity layer was from 6.16 Ωm to 332 Ωm in the first geo-electric layer and its thickness range from 2.77 m to 37.7 m and a depth range of 2.77 m to 37.7 m. the range of the second resistivity layer was from 16.5 Ωm to 37.9 Ωm which has the range of its thickness from 4.1 m to 10.7 m. The range of the third resistivity layer was from 101.2 Ωm to 288.2 Ωm which has the range of its thickness from 38.9 m to 99.7 m, and the first aquifer in the area. The range of the first resistivity layer was from 100.7 Ωm to 214.3 Ωm which has the range of its thickness from 28.5 m to 94 m. The fifth layer which is the second aquifer and has resistivity from 254 Ωm to 350 Ωm with a very large thickness. The range of the first resistivity aquifer is from 101.2 Ωm to 288.2 Ωm and the range of the second resistivity aquifer is from 253.8 Ωm to 350.1 Ωm. The 2D ERT profiles unveiled areas with low resistant zones and later discussed as zones penetrated by contaminants originated from dumpsites whereas high resistant zones represent areas of low or non-conductive materials in the area. Data obtained from four dumpsites indicated that leachate of the waste dumpsites penetrated into aquifers and polluted the groundwater. The existence of contaminants in the water was noted by a decrease in the formation resistant values. It is seen, from the results of the survey (geophysical) that the water in the area is polluted and it accounts for the prevalence of any disease related to water that are common in the are

Occurrence of pathogenic bacteria associated with Clarias gariepinus in selected fish farms of Kumbotso local governement area of Kano state, Nigeria

With the diminishing rate of natural fish resources globally, a reasonable percentage of fish and fish products supply now comes from aquaculture. However, quality production is highly required for sustainable demand and supply. It is in view of the aforementioned that this study was designed to examine the quality status of Clarias gariepinus in relation to pathogenic bacteria in two fish farms in Kumbotso Local Government Area of Kano State, Nigeria. 66 Clarias gariepinus with bodyweight 17g - 215g were randomly sampled from July to December 2012 followed by the isolation and identification of different pathogenic bacteria from skin and gill. A total of 132 samples comprising skin (1cm2) and gill (1g) were subjected to microbiological assays in the laboratory following standard procedures. Nutrient Agar, MacConkey Agar, Eoisin Methylene blue, Salmonella Shigella Agar and Blood Agar were used for isolation and maintenance of cultures during the study. Lactose broth, Brilliant Green lactose bile broth (BGLB) was used for the estimation of Escherichia coli Most Probable Number per 1cm2 of skin and 1 gram of gill (MPN/ml and MPN/g). The highest mean of Aerobic Plate Count (APC) was 1.26 x 104 cfu/ml while the highest mean of Escherichia coli MPN/1cm2 was 8.75. Bacterial pathogens isolated and percentage occurrences in parenthesis were Escherichia coli (54.27 %); Stapholococcus aureus (22.48 %); Pseudomonas aeruginosa (10.85 %); Salmonella paratyphi (9.30 %) and Enterobacter aerogenes (3.10 %). There was no significant difference (χ2 = 3.42, P > 0.05) in bacteria isolates from the two fish farms. The result from this study indicated that the fishes were less contaminated with pathogenic bacteria, thus consumers are safe to eat fishes harvested from these farms since all the values are within the recommended limit of < 5 x 105 cfu/g for APC and, 11 for Escherichia coli MPN/ml by International Commission for Microbiological Specification for Food (ICMSF, 2007).Keywords: Fish farm, Clarias gariepinus, Microbiological assays, Pathogenic bacteria

Catalytic Transformations of Alkynes via Ruthenium Vinylidene and Allenylidene Intermediates

NOTICE: This is the peer reviewed version of the following book chapter: Varela J. A., González-Rodríguez C., Saá C. (2014). Catalytic Transformations of Alkynes via Ruthenium Vinylidene and Allenylidene Intermediates. In: Dixneuf P., Bruneau C. (eds) Ruthenium in Catalysis. Topics in Organometallic Chemistry, vol 48, pp. 237-287. Springer, Cham. [doi: 10.1007/3418_2014_81]. This article may be used for non-commercial purposes in accordance with Springer Verlag Terms and Conditions for self-archiving.Vinylidenes are high-energy tautomers of terminal alkynes and they can be stabilized by coordination with transition metals. The resulting metal-vinylidene species have interesting chemical properties that make their reactivity different to that of the free and metal π-coordinated alkynes: the carbon α to the metal is electrophilic whereas the β carbon is nucleophilic. Ruthenium is one of the most commonly used transition metals to stabilize vinylidenes and the resulting species can undergo a range of useful transformations. The most remarkable transformations are the regioselective anti-Markovnikov addition of different nucleophiles to catalytic ruthenium vinylidenes and the participation of the π system of catalytic ruthenium vinylidenes in pericyclic reactions. Ruthenium vinylidenes have also been employed as precatalysts in ring closing metathesis (RCM) or ring opening metathesis polymerization (ROMP). Allenylidenes could be considered as divalent radicals derived from allenes. In a similar way to vinylidenes, allenylidenes can be stabilized by coordination with transition metals and again ruthenium is one of the most widely used metals. Metalallenylidene complexes can be easily obtained from terminal propargylic alcohols by dehydration of the initially formed metal-hydroxyvinylidenes, in which the reactivity of these metal complexes is based on the electrophilic nature of Cα and Cγ, while Cβ is nucleophilic. Catalytic processes based on nucleophilic additions and pericyclic reactions involving the π system of ruthenium allenylidenes afford interesting new structures with high selectivity and atom economy

Synthesis and Evaluation of Antimicrobial Activity of Two Schiff Bases Derived From Cyclohexylamine

Design and development of novel materials with outstanding antimicrobial properties has transpired to hinder and regulate the growth of microorganisms. Indubitably, Schiff bases are the magic bullet that have efficient antimicrobial properties against various pathogenic strains. The Schiff bases, L1 and L2 reported herein were respectively synthesized by equimolar condensation of benzophenone with cyclohexylamine and 2,4-dihydroxybenzophenone with cyclohexylamine. The products were obtained in excellent yield of 66 and 75 %. The Schiff bases were subjected to solubility test, melting point determination and FT-IR spectroscopic analysis. They were found to show relative thermal stability with melting points of 220 and 195 oC and solubility in methanol, acetone and dimethylformamide of the solvents used. The FT-IR confirmed the formation of the Schiff bases with appearance of azomethine (C=N) peak at 1652 and 1592 cm-1. The in vitro antimicrobial activity of the Schiff bases was tested against two gram positive bacteria (Staphylococcus aureus and Streptococcus pyogens) and two gram negative (Pseudomonas aureginosa and Escherichia coli) as well as two fungi strains (Aspergillus Niger and Candida albicans). The results reveal that the Schiff base L2 shows promising activity against all the pathogen under investigation. However, no activity was observed for L1 against the microbes except Streptococcus pyogens

Determination of the yield of intercropped maize in Bauchi, Nigeria, using correlation and path coeffecient analysis

No Abstract. IJOTAFS Vol. 1 (2) 2007: pp. 110-11

Effect of maize-legume mixture and nitrogen rates on the n-uptake and fertilizer n-recovery by maize inercrop

No Abstract. IJOTAFS Vol. 1 (2) 2007: pp. 149-15