On Being an Entrepreneur: the Nigerian Perspective

It is common knowledge that the success of an economy rests on the strength of its entrepreneurs. Present-day challenges make it imperative for countries in the same bracket as Nigeria to deemphasize reliance on oil and government for social crumbs, to embrace innovative activities and deepen small and medium-scale enterprises (SMEs). SMEs are important drivers of economic growth but they face significant challenges as obtained in Nigeria where infrastructures such as power, transportation and financing needed to make entrepreneurship work seldom exists. With a high unemployment rate, young Nigerians are required to embrace entrepreneurship. The aim of this paper is to present the Nigerian entrepreneur within the country’s challenging business environment as a true definition of an entrepreneur despite the general definition. We presented a set of questions and gathered feedback through a set of questionnaires administered using purposive sampling on 6 trade associations in Iwo Town, Osun state, Nigeria

Facile Synthesis and Characterization of New 2,3-Disubstituted Benzimidazole Derivatives

Benzimidazoles are known to represent a class of medicinally important compounds which are extensively used as antibacterial agents. Hence, a series of five 2-substitutedbenzimidazole precursors (1a-e) were synthesized via [4 + 1] condensation and imino compound (1f) by simple condensation in the presence of Conc. HCl as catalyst. Synthetic modification of N-1 position was achieved in order to obtain new 5-chloro-2,4-dinitrophenyl bearing 1,2-disubstituted benzimidazole 2a-e and 2f, and 3-chlorobenzyl bearing 1,2-disubstituted benzimidazole 3a-e and 3f in good to excellent yields using a facile approach. The chemical structures of all synthesized compounds were confirmed using spectroscopic means such as UV-visible, IR, Mass spectra, 1H and 13C NMR as well as C, H, N elemental analytical data

Adsorption Behaviour of [(4-Hydroxy-6-methyl-2-oxo-2Hpyran- 3-yl)-(4-methoxy-phenyl)-1methyl]-urea on Stainless Steel in Phosphoric Media

The adsorption of [(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)-(4-methoxy-phenyl)- methyl]-urea on iron in phosphoric media was studied by using electrochemical technique. The adsorption mechanism was investigated using adsorption isotherms. The experimental data fit localized adsorption models. The values for free energy of adsorption, o DGads , were also calculated at each surface coverage, �, of the studied compound by applying the mathematical model of Bockris – Swinkels adsorption isotherm. The variation of free energy of adsorption o ads DG with surface coverage, �, was interpreted in terms of deviation from ideal condition assumed in Langmuir model. A possible adsorption model of HPU2 molecules on to the metal surface was suggested

Synthesis, characterization, antimicrobial activity and toxicology study of some metal complexes of mixed antibiotics

Mixed ligand metal complexes of ampicillin and chloramphenicol prepared by using Ni(II), Co(II) and Fe(III) metal chloride hexahydrate were reported and characterized based on some physical properties and spectroscopic analysis such as AAS, UV, and IR spectroscopy. The complexes were proposed to have the formulae [ML1L2](Cl)n ( where M= Ni(II), Co(II), Fe(III); L1 = ampicillin, L2 = chloramphenicol, and n=2-3). IR spectra suggested that both L1 and L2 coordinated to the metal ions in a terdentate manner with �(O-H), �(C=O) and �(N-H) as donor sites in each of the ligands. From analytical and spectroscopic data obtained, the complexes were proposed to be of octahedral. The synthesized complexes, in compares to their ligands, were also screened for their antibacterial activity against isolated strains of Escherichia coli, Staphylococcus aureus and Klebsiella pneumonia by using agar diffusion method. The activity data showed the metal complexes to be more potent antibacterial than the parent drugs against the three bacteria species. However, toxicology tests against some tissues of albino rat (Rattus novergicuss) revealed toxicity of the complexes as compared to the parent drugs because the complexes were found to significantly increase (P<0.05) alkaline phosphatase from homogenates of liver and kidney tissues of the tested doses. However, there was no significant difference (P>0.05) in ALP of rat serum. The results generally indicated that more potent compounds with better physical properties and enhanced antimicrobial activities upon complexation have been prepared

Fe(III) and Co(II) complexes of mixed antibiotics: synthesis, characterization, antimicrobial potential and their effect on alkaline phosphatase activities of selected rat tissues

Two new mixed ligand metal complexes of Fe(III) and Co(II) chloride hexahydrate salts were prepared using standard methods. Ampicillin trihydrate and oxytetracycline hydrochloride antibiotics were used as ligands. Chemical analysis including conductivity measurements, molecular weight determination and spectroscopic studies were used to propose the geometry and mode of binding of the ligands to metal ions. Both ligands were proposed to coordinate to metal ions in ratio 1:1:1 in the complexes. Each of the ligands acted as terdentate ligand. Inhibition properties as well as toxicity effect of administration of the metal complexes at the dose of 3.33 mg/kg body weight thrice daily for 5 days on the alkaline phosphatase (ALP) activities on rat kidney, liver and serum were evaluated. The inhibitory properties of the complexes were found to be significantly different (P<0.05) at the concentration of 1%(w/v) as compared to each of the ligands. The complexes were found to significantly increase (P0.05) in ALP from liver and kidney sera. The results indicated that more potent compounds with better physical properties and enhanced antimicrobial activities upon complexation have been prepared

Assessment of ground water pollution in the residential areas of Ewekoro and Shagamu due to cement production

Chemical and physico&ndash;chemical parameters of ground water samples from wells were analyzed by multivariate statistical tools to provide the characterisation of the ground water distribution of the settlements around cement factories in Ewekoro and Shagamu, Ogun State in Nigeria. The 17 parameters determined include: pH, conductivity, dissolved oxygen (DO), total dissolved solids (TDS), biochemical oxygen demand (BOD), total hardness, acidity, and alkalinity; anions such as chlorides, sulphates, phosphates and nitrates as well as potentially toxic metals such as copper, lead, zinc, iron and cadmium. The analytical data were obtained from 6 wells in Ewekoro and 11 wells in Shagamu sampled during three different periods along a year covering both the wet, break and dry seasons of 2009. The concentrations of lead and cadmium are above the World Health Organisation (WHO) standard in all three seasons investigated with lead having as high as 1.05 mg/L and maximum of 0.068 mg/L for cadmium. It was also observed that the levels of sulphate was higher that the WHO standard during the dry season with a maximum concentration of 623 mg/L. All other physicochemical parameters fell within the permissible range as stipulated by the WHO. There was no seasonal difference in the concentrations of the potentially toxic metals analysed in the ground water from the two sites, while for the physicochemical properties, there was a seasonal variation in the results of the ground water quality in the two sites studied with DO having a p-value of 0.009, BOD with p-value of 0.04 and Alkalinity of 0.044 p-value. An approach for the characterisation of the groundwater system of the neighbourhood of the cement factories is proposed on the basis of its physico-chemical composition, in order to detect multivariate patterns for unpolluted waters as well as for eventual polluted zones.Key words: Toxic metals, physico-chemical composition, multivariate, cement, ground water

Synthesis, physical properties, antimicrobial potentials of some mixed antibiotics complexed with transition metals and their effects on alkaline phosphatase activities of selected rat tissues

Mixed ligand metal complexes of chloramphenicol and oxytetracycline were prepared by using Ni(II), Co(II) and Fe(III) metal chloride hexahydrate. They were characterized based on some physical technique and spectroscopic analysis such as AAS, UV, and IR spectroscopy. Based on the analytical and spectroscopic data, the complexes were proposed to have the formulae [ML1L2](Cl)n (where M = Ni(II), Co(II), Fe(III); L1 = chloramphenicol, L2 = oxytetracycline and n = 2 - 3). IR spectra suggested that both L1 and L2 coordinated to the metal ions in a terdentate manner with �(O-H), �(C=O) and �(N-H) as donor sites in each of the ligands. The complexes were proposed to be of octahedral. The synthesized complexes, in compares to their ligands, were screened for their antibacterial activity against isolated strains of Escherichia coli, Staphylococcus aureus and Klebsiella pneumonia by using diffusion method. The activity data showed the metal complexes to be more potent antibacterial than the parent drugs against the three species. Toxicology tests against some tissues of albino rat (Rattus novergicuss) revealed toxicity of the complexes as compared to the parent drugs. Ni(II) complex was found to possess no significant difference (P > 0.05) in alkaline phosphatase from both homogenates of liver and kidney and rat serum. However, Co(II) and Fe(III) complexes were found to significantly increase (P < 0.05) alkaline phosphatase from homogenates of liver and kidney tissues of the tested doses but there was no significant difference (P > 0.05) in alkaline phosphatase from rat serum

Physicochemical characteristics and heavy metal levels in soil samples obtained from selected anthropogenic sites in Abeokuta, Nigeria

This study assessed the effect of heavy metals introduced into the soils through human activities which can bio-accumulate in plants and passed to man via the food chain that can pose health risk. Topsoil samples were collected from selected anthropogenic and control sites (dumpsites, mechanical workshops, abattoirs, fuel filling stations and hospital incinerators) in Abeokuta, Nigeria at the depths 0-5cm, 5-10cm and 10-15cm. Physicochemical parameters such as pH, moisture content, bulk density, organic matter, organic carbon, particle size distribution and Mn, Zn, Pb, and Cd were analyzed in soils using standard methods. Soil pH values ranged from 5.17 - 8.28, moisture content ranged from 3.50 - 28.55 %, bulk density ranged from 0.78 - 2.29 gcm-3, organic matter ranged from 0.09 - 16.01 %, organic carbon ranged from 0.02 % - 8.48 %. Mean concentrations of heavy metals (mgkg-1) ranged from 182.69 ± 61.95 - 697.06 ± 85.62; 122.69 ± 30.04 - 632.94 ± 508.79; 19.38 ± 6.72 - 158.50 ± 71.41; 0.25 ± 0.00 - 1.63 ± 1.38 for Mn, Zn, Pb and Cd respectively. Distribution pattern of heavy metals in petrol stations, abattoirs, mechanic workshops and hospital incinerator sites were Mn &gt; Zn &gt; Pb &gt; Cd, while for dumpsites Zn &gt; Mn &gt; Pb &gt; Cd. Pollution index indicated that soil qualities varied between slightly contaminated to severely polluted status. This showed that the heavy metal contamination of the soils does not call for any alarm; proactive measures must be taken to minimize accumulation of these metals.Keywords: Heavy metals, dumpsites, pollution, physicochemical parameters,  abattoirs and soil

Comparison of extraction and clean-up techniques for the determination of polycyclic aromatic hydrocarbons in contaminated soil samples

The development of a fast, efficient and quantitative technique for the extraction, clean-up, and preconcentration of the 16 United States Environmental Protection Agency (USEPA) priority polycyclic aromatic hydrocarbons (PAHs) was carried out on contaminated soils. The effect of Soxhlet, ultrasonication and mechanical shaking used in the extraction of a low-level PAH soil certified reference material (CRM131-100) was investigated. Six different extraction solvents: acetone, cyclohexane, 2- propanol, methanol, acetonitrile and dichloromethane, were tested to select the most suitable solvent for the extraction of the 16 PAHs from the certified soil reference material. The results were compared to determine the method with the highest extraction efficiency. The clean up and preconcentration procedures for the PAHs were optimised using the solid phase extraction (SPE). Acetonitrile, dichloromethane and tetrahydrofuran were tested as eluants for the optimisation of SPE clean up. Chromatographic conditions for the separation of PAHs using High Performance Liquid Chromatography (HPLC) using UV-DAD and fluorimetric detection with programmed excitation and emission wavelengths were also optimised. The optimised ultrasonic extraction procedure and SPE clean-up extracted the PAHs from the certified reference material with recoveries ranging from 63.6 % to over 100%.Key words: High Performance Liquid Chromatography (HPLC), mechanical shaking, polycyclic aromatic hydrocarbons (PAHs), soil, solid phase extraction (SPE), soxhlet extraction, ultrasonication

Transmission Network Enhancement with Renewable Energy

Wind and solar energy play an important role in the de - carbonization of electricity generation. However, high shares of these Variable Renewable Energies (VREs) challenge the power system considerably due to their temporal fluctuations and geographical dispersion. This paper systematically reviews and analyzes transmission grid extensions as an integration measure for VREs. Effects of grid extensions for fundamental properties of the power system as a function of the penetration and mix of wind coupled with solar energy were revealed in the study. The paper also provides an overview of the system implication of wind and solar PV energy and investigates a way to partly overcome transmission grid extension