Sulphuric Acid Corrosion of Mild Steel in Leave Extracts of Cnidoscolus aconitifolius Plant

Alkaloid and nonalkaloids extracts of Cnidoscolus aconitifolius leaves is reported as corrosion inhibitor of mild steel in HCl. Conventional weight loss measurements and Tafel polarization techniques are employed to study the effect on mild steel corrosion in H2SO4 solutions. The weight loss result revealed that both plant extracts are excellent corrosion inhibitors. Electrochemical polarization data revealed that mixed mode of inhibition. The increase in %IE with change in concentration of the extracts suggests the strong adsorption of active molecules leading to the formation of a protective layer on the mild steel surface.  It was found that adsorption of both leaf extracts followed Langmuir adsorption isotherm model. Keywords: Weight loss, Langmuir isotherm, activation energy, corrosion current density, inhibition efficiency, Cnidoscolus aconitifolius

Inhibition and Adsorption impact of Leave Extracts of Cnidoscolus Aconitifolius on Corrosion of Aluminium Sheet in 1 M Hcl Medium

Corrosion inhibition in the presence of alokaloid and non alkaloid extracts of Cnidoscolus aconitifolius in 1M HCl was studied using the weight loss and hydrogen evolution techniques at 303, 313 and 333 K. The results obtained revealed that the inhibition efficiency decreased with increase in temperature. Inhibition occurred through adsorption of the alokaloid and non alkaloid extracts molecules on the metal surface. The apparent activation energies, enthalpies and entropies of the dissolution process and the free energies and enthalpies for the adsorption process were determined and discussed. The fundamental thermodynamic functions were used to evaluate important inhibitive properties of Cnidoscolus aconitifolius.Keywords: Activation energy; Gibb’s Free Energy; Langmuir adsorption; Cnidoscolus aconitifolius; Aluminium sheet

FORMULATION AND IN-VITRO EVALUATION OF THEOPHYLLINE HYDROCHLORIDE EFFERVESCENT FLOATING TABLETS: EFFECT OF POLYMER CONCENTRATION ON TABLET BUOYANCY

Objective: This study was undertaken to formulate a floating drug delivery system of theophylline hydrochloride using different concentrations of a chosen polymer and then investigate how polymer concentration affects buoyancy and drug release properties of the tablets. Methods: Hydroxypropyl methylcellulose (HPMC) at different concentration levels of 15% (F1), 20% (F2) and 30% (F3) was used to form the three formulation batches of floating tablets. Wet granulation method was used for the granule preparation while Sodium bicarbonate and citric acid were used as the gas generating agent. The physical properties of the granules and the floating tablets were evaluated. Also determined were the physicomechanical properties, buoyancy and swelling characteristics of the tablets. The in vitro drug release study was carried out according to the USP I (basket method) for 8h in 900 ml 0.1N HCl at 50 rpm. Samples withdrawn at the regular predetermined time were analyzed spectrophotometrically at a wavelength of 271 nm and data obtained statistically analyzed by one-way analysis of variance (ANOVA). The differences between means were considered significant at P<0.05. Results: The result showed that polymer (HPMC) concentration significantly (p>0.05) increased swelling index and improved floating lag time, it had no significant effect on the total floating time. Percentage drug release at the end of 8 h was 100%, 98.2% and 96.13% for formulation F1, F2 and F3, respectively. All three formulations followed the Higuchi drug release kinetics model and the mechanism of drug release was the non Fickian diffusion with exponents of 0.46, 0.51 and 0.56 for the respective batch. Conclusion: Batch F3 gave a better-controlled drug release and floating properties in comparison to batch F1 and F2 thus Polymer concentration influenced the onset of floating and controlled the release of Theophylline

Empirical Analysis of Egg Production Functions: A Case Study of Ikot Ekpene and Uyo Metropolis of Akwa Ibom State, Nigeria

The study carried out an empirical analysis of egg production functions, a case Study of Ikot Ekpene and Uyo Metropolis of Akwa Ibom State, Nigeria. Specifically, this study was carried out to estimate the egg production functions in the study area, determine the resource use efficiency of egg producers in the study area and to make recommendations based on the findings. Data for this study were obtained from primary source collected from thirty – seven (37) purposively selected poultry farmers using personal observations and interview method while the secondary data were obtained from farm records kept by the farmers. Regression analysis was carried out to show the relationship between egg lay and several input explanatory variables namely; feed intake, mortality rate, culling rate, labour and floor space. Resource use efficiency analysis was used to determine the rationality of the firms in their use of resources. The result showed that the effect of feed intake and labour on egg lay was significant at 0.01% level, Floor space was also significant at 0.01. Further analysis showed that sum of elasticities for feed, labour and floor (EP) is1.59 indicating an increasing return to scale scenario, implying that a 1% increase in the variables; feed, labour, and floor space will lead to a 1.59% increase in egg lay. Of all the four egg production function estimated in this study, it became clear that the exponential function was found to be the lead equation since four out of the five variables employed in this study were significant where as other forms had less numbers of significant variables. The analysis with respect to resource use showed that feed, labour and floor space were over utilized during the period of egg lay

PRELIMINARY INVESTIGATIONS INTO THE PHYSICOCHEMICAL AND COMPACTION CHARACTERISTICS OF MODIFIED STARCH OF DISCOREA ALATA USING DICLOFENAC SODIUM TABLET

Objective: This work focused on evaluating the micromeritic and compressional properties of pregelatinized African water yam (Discorea alata) starch and its modified forms with comparison to pregelatinized corn starch and microcrystalline cellulose.Methods: Two modifications of the water yam starch were prepared; acetone dehydrated pregelatinized form (DSA) and an admixture of DSA and pregelatinized corn starch (CDSA). A third form of starch is the acetone dehydrated pregelatinized corn starch (CSA). These were used to form batches compacted as tablets using diclofenac sodium as the active moiety. Physicochemical and flow characteristics of the starch powders were elucidated, and the drug starch compatibility studies done using the Fourier transform Infra-red (FTIR) technique. Compaction studies were investigated on tablets formed at different compression pressures and Heckel plots were prepared.Results: The slope of the straight line (K) of 0.8959 was greatest for F1 while yield pressure (Py) value of 10.965 was highest for F3. These values from the Heckel plot suggest that while the tablets of control batch of microcrystalline cellulose (F4) and a batch of pregelatinized corn starch (F2) formed harder compacts, less likely deformed plastically, the Discorea alata batch (F1) and the admixed batch (F3) were likely to deform plastically. Also, the binding efficiency of the compact was significantly high (47.81%Kgscm-1) for F4 at 56.5Kpas compaction pressure, higher than that obtainable for any of the other formulations at the compaction pressures under consideration. All starches formed had similar moisture content (of 10%) despite the different sources but the interaction between the water molecule and pregelatinized water yam starch improved as revealed by viscosity(7.18mPas), hydration capacity(3.27%) and swelling index (250%) of CDSA.Conclusion: It could be concluded that pregelatinized water yam starch could be used as a substitute for corn starch or microcrystalline cellulose as a pharmaceutical excipient (binder/filler) in tablets formulation

Response of Late Season Maize/Soybean Intercropping to Nitrogen in the Humid Environment of South Southern Nigeria

Intensification of maize/legume production during early rains in the High Rainforest region of South Southern Nigeria is limited by heavy rainfall. Production of late season maize/legume by peasant farmers is gaining prominence though yields are low due to low soil fertility and improper crop arrangement. The objective of this research was to investigate the yield performance of late season maize/soybean intercropping in response to nitrogen fertilization and spatial arrangement of the intercrops. The trial was a split-plot design in randomized complete block with three replications. Treatments consisted of five rates of nitrogen (0, 25, 50, 75 and 100 kg ha-1) and five crop arrangements (sole maize at 53,333 plants ha-1, sole soybean at 266,666 plants ha-1 and maize: soybean additive mixture arrangements of 1:1, 2:2 and 1:2). Nitrogen fertilization increased yield in both maize and soybean at all the treatment levels, when grown sole or in mixtures. Application of 100 kg N ha-1 to maize increased number of ears per plant, 100-grain weight, cob yield and grain yield by 46, 35, 138 and 153 percents, respectively in 2007, and by 15, 48, 88 and 109 percents, respectively in 2008, over no nitrogen application. Similarly, application of 100 kg N ha-1 to soybean increased number of pods per plant, number of barren pods and 1000-seed weight by 53, 120 and 16 percents, respectively in 2007, and by 55, 99 and 14 percents, respectively in 2008, over no nitrogen application. Optimum seed yield in soybean was obtained at 50 kg N ha-1. The yield values of 1,352.8 and 1,158.2 kg ha-1 were higher than those obtained at 0 kg N ha-1 by 31 and 21 percent in 2007 and 2008. Increasing the nitrogen level further to 100 kg ha-1 depressed seed yield by 8 percent in 2007 over 0 kg ha-1. The nitrogen x crop arrangement interaction effects on grain yield and all other parameters were not significant (p< 0.05). Late season maize and soybean populations may be superimposed on each other and fertilized with 50 kg N ha-1 to take advantage of optimum soybean seed yield and 66-76 percent of the maize grain yield. Key words: maize, soybean, intercropping, additive mixtures, nitrogen fertilize

Inhibition and Adsorption impact of Leave Extracts of Cnidoscolus Aconitifolius on Corrosion of Aluminium Sheet in 1 M Hcl Medium

Corrosion inhibition in the presence of alokaloid and non alkaloid extracts of Cnidoscolus aconitifolius in 1M HCl was studied using the weight loss and hydrogen evolution techniques at 303, 313 and 333 K. The results obtained revealed that the inhibition efficiency decreased with increase in temperature. Inhibition occurred through adsorption of the alokaloid and non alkaloid extracts molecules on the metal surface. The apparent activation energies, enthalpies and entropies of the dissolution process and the free energies and enthalpies for the adsorption process were determined and discussed. The fundamental thermodynamic functions were used to evaluate important inhibitive properties of Cnidoscolus aconitifolius

Nutrient Status and Ameliorating Effects of Poultry Droppings on Soil pH and Sustainable Production of Garden Egg

Sustainable production of crops on tropical soils requires soil amendment to remediate soil acidity status and raise fertility level. Industrial lime and inorganic fertilizers are either not available or too expensive to buy. This study was carried out with the objective of investigating the effects of poultry droppings on soil acidity amelioration and increased fertility for sustained production of garden egg (Solanum aethiopicum L.).The field trials were conducted at the Teaching and Research Farms of the University of Agriculture, Makurdi, and the Faculty of Agriculture, Cross River University of Technology, Obubra in 2009 and 2010. Two varieties of African garden egg (Gilo and Kumba) and three rates of poultry droppings (5, 10 and 15 t ha-1) were in factorial combinations. The experiment was laid out in a Randomized Complete Block Design with three replications.  The results obtained showed that all rates of the manure reduced the soil pH within 30 days after incorporation in both years and locations. At 60 days after application, and up to 140 days after incorporation, all manure rates increased the soil pH in both locations and years. The highest increase occurred with 15 t ha-1 poultry droppings at 140 days after incorporation. With no manure application, there was a steady decrease in pH up to the harvest time. All manure rates significantly (P<0.05) increased the yield of the garden egg varieties over when no manure was used. Poultry droppings at 15 t ha-1 produced the highest fruit yield in both years and locations. The crop yields were significantly (p<0.05) higher in Makurdi than Obubra in both years. Yield for 2010 was significantly higher than 2009 in both locations. Poultry dropping at the rate of 15 t ha-1 may be used to remediate soil pH and improve fertility for sustainable production of garden egg in the Guinea savanna or the Rainforest agro-ecologies