In this study the distribution of silt, clay and exchangeable properties of aggregate sizes of four soils were evaluated. The four soils studied were Entisol at Nsukka, Ultisol at Nsukka, Inceptisol at Eha-Amufu and Inceptisol at Ikem, all collected from four different sites in Nsukka area of southeastern, Nigeria. The land use types considered were fallow and cultivated. Soil samples collected from 0-25mm depth were air-dried at room temperature and were separated into five aggregate fractions 2.0-5.0mm, 1.0-2.0mm, 0.5-1.0mm, 0.25-0.5mm and < 0.25mm. Changes in the distribution of silt, clay and exchangeable properties of aggregate sizes of the four soils under wet and dried sieving of the four soils following cultivation were determined. The result of the study showed that Inceptisol had the highest silt, clay content in all the aggregate sizes among the four soils. The trend is Inceptisol > Entisol > Ultisol. Cultivation decreased the exchangeable bases, CEC and percent base saturation of those soils and their values were higher in the dry-sieved samples than wet-sieved ones. On the average acidity value of the dry-sieved samples were found to be higher than those of the wet-sieved samples. The variation in pH values of the aggregate fractions was found to be associated with the total exchangeable bases and percentage base saturation of the aggregates. Results obtained showed relative changes in the properties of dry and wet-sieving, even though their diameters are the same, implying that their loss during erosion will have differing effects on the soils.
Aims: The aim of this study was to identify and map the vulnerability of the study area to climate change. Study Area: Located in the South Eastern coastal area of Nigeria, Akwa Ibom State is highly vulnerable to hazards that are associated with climate change – erosion, flooding and sea level rise. Methodology: In this research, some of the key determinants of vulnerability were identified and mapped based on recommendations in literature. Data on the three main vulnerability components of exposure, sensitivity and adaptive capacity were produce and combined in a Geographic Information System (GIS) environment to reveal the vulnerability of the study area to climate change. Results: The resultant vulnerability surface showed that the High vulnerability class covers an area of 616 km2 (9%), Medium 4996 km2 (73%), and Low 1232 km2 (18%). While High Vulnerability areas are found in parts of Uyo, Ikot Ekpene, Eket, Itu, Nsit Ibom, Okobo, Oron and Itu, Medium in the other North East and Southern LGAs, and the Low vulnerability are found in the North East portion of the study area. Conclusion: The study has revealed the ability of vulnerability maps to communicate information concerning environmental risks. In this way, disaster impact reduction can be communicated effectively to stake holders, hence leading to a better understanding of climate change mitigation.
Aims: To determine the gamma dose rates and radionuclide concentration levels in soil samples from the Federal University of Technology, Owerri, Nigeria. Study Design: Sixty (60) soil samples were collected at different locations in the Federal University of Technology, Owerri, Nigeria. Each prepared sample was placed symmetrically on top of a lead-shielded NaI (Tl) detector for measurement. Place and Duration of Study: Federal University of Technology, Owerri, Nigeria, between April 2013 and October 2013. Methodology: A γ-ray spectrometry in the Radiation and Health Physics Research Laboratory, University of Ibadan, Nigeria was employed to carry out the radioactivity measurement of the 60 soil samples. The activity concentrations, absorbed dose rate in air as well as annual effective dose equivalent were calculated. Results: The activity concentrations of 40K, 226Ra and 232Th ranged from 21.90±1.62Bqkg-1 – 142.45±1.37Bqkg-1, < 3.65Bqkg-1 - 36.01±2.25Bqkg-1 and <4.43Bqkg-1 – 43.87±0.75Bqkg-1 respectively. The average absorbed dose rate was calculated as 25.99±8.35nGyh-1 while the annual effective dose equivalent ranged between 9.39µSvy-1 and 56.83µSvy-1 with an average of 31.89±10.25µSvy-1. These values are less than the world average values of absorbed and effective doses which are 51nGyh-1 and 70µSvy-1 respectively. Conclusion: Human activities and the presence of radioactive minerals on the campus of the Federal University of Technology, Owerri, Nigeria have not increased the radionuclide concentrations in the University environment beyond safety limit.
The cocoa (Theobroma cocoa Linn.) is the main foreign exchange earner and the backbone of the Ghanaian economy. However, over the years the production levels begun to dwindle and in the attempt to resuscitate the industry, the government introduced a technology package and social intervention to address it. The technology package consists of 25 unique attributes (classes of characteristics or components), of which some farmers adopted test part of it and left out others. The study seeks to determine socioeconomic factors influencing farmers’ choice decision process and preferences for attributes of the technology packages. The results from the multinomial logit regression model revealed that availability of labour, gender, farm size, age of the cocoa farm, years of cocoa farm ownership and number of cocoa bags harvested per annum are the key variables influencing farmers’ choices. Moreover, farmers who have long experience in cocoa cultivation and have had some form of training on the technology packages have high probability to adopt entire categories or classes of the technology package. Thus, institutional policy arrangement which emphasizes on training and targeting experience farmers will go a long way to enhance production level in the country.
This work studies the physical properties of ceiling boards produced from waste paper. The ceiling boards were produced using waste paper, fire retardant and cement of varying quantities. The compression of the boards was done using hydraulic press. From the results, it was observed that the ceiling board produced with 100% fiber from waste paper met with the commercial fiber ceiling board standard to about 4/7 of both calculated and measured properties; giving 415kg/m3 density, 660kpa compressive strength, 809 hardness and 2.5KJ impact strength. The trend of quality of boards produced decreased as follows: 100>70>90>80>60.
Aims: A dissolved oxygen controller was designed to optimize photovoltaic energy and maintain minimum DO variations in the fish tanks, independent on environmental conditions. Study Design: Software critical parameters have to be tuned including discontinuous routine (DR) interval, use throughout the night and cloud sensing. Place and Duration of Study: Department of Irrigation at Tlapeaxco, Texcoco, Mexico at the Universidad Autonoma Chapingo, between April and July 2011. Methodology: The controller was assembled and its software tested to maintain the desired water dissolved oxygen concentration in the tanks. Solar radiation and clouds presented during May and June of 2011 were monitored correlating an infrared sensor with a sunshine indicator. Energy produced by the solar panels was acquired with a data logger together with the energy stored in the batteries; overvoltage and deep discharges were avoided by the battery. A discontinuous routine was turned on when clouds were present, evaluating whether it should operate during all the night. Results: May presented 26 cloudy days and 45% of these days presented less than 2 hours of more than 1000 W/m2 of irradiation. Cloud cover sensing correlation between the infrared and sunshine sensor has a R2=0.97. Cloud cover peaks can last from minutes to hours and using the one-hour discontinuous routine (DR) instantaneous peaks were avoided. Optimal DR period was ten minutes as it saves the same quantity of energy but maintains dissolved oxygen (DO) concentration over 4.1 ppm; hourly DR intervals, decreases DO to 2.4 ppm stressing the carps. Battery charge should be at least 39 Ah@19:00 to supply the energy required by the aerators during the night. Conclusion: A sunshine sensor was selected to detect cloud cover and its sampling period was decreased from ten to one minute. DO concentration on tanks became more stable when the ten minute discontinuous period was employed.
Aim: Conflict management is a factor that determines whether farmers production level increases or not since conflict is an inevitable phenomenon in the society. Oke-Ogun areas have been witnessing several violent conflicts of which farm settlements, properties and lives were destroyed. Quest for empirical data concerning effect of conflict management by farmers in the area necessitate this research. Study Design: Structured interview guide was used to elicit information from 120 respondents each from core conflict (CCA) and outside conflict areas (OCA). Place and Duration of Study: The study area Oke-Ogun area of Oyo State was chosen given its prevalent conflict occurrences. Study duration 2 years. Methodology: Using simple random sampling techniques respondents were sampled from four blocks as stratified by the Oyo State ADP. Data collected were analyzed using frequency counts, percentage and t-test analyses. Results: The result showed that 72.65% of the farmers in (CCA) and OCA (69.22%) were in the age category of 18-45 years. Farming was the main livelihood of respondents in CCA (83.76%) and OCA (77.88%). Prominent reason adduced for conflict by farmers is competition for natural resources (86.42%). Farmers in CCA recorded lower mean production level for maize 62.25 tones, yam 1152 tones and cassava 1232 tones as oppose to higher mean production level recorded for maize 310.5 tones, yam 3505 tones and cassava 11,185.6 tones OCA. Result of the t-test showed a significant difference in crops production level between CCA and OCA at p<0.05. Conclusion: The study therefore concluded that conflict management employed by farmers had negative influence on farmers production level. It is recommended that farmers should avail themselves of training opportunities on conflict management and resolution in order to ensure peaceful co-existence among themselves which is a factor for increase in production.
Monodispersed silica nanoparticles (SNPs) were synthesized by cost effective aqueous-ethanolic route. The particle size was controlled by optimizing the synthetic conditions. The synthesized different size SNPs were used to study the corrosion protection efficiency on aluminium (Al) in alkaline medium by weight loss, Potentiodynamic polarization and surface morphology examination methods. It was found that SNPs with smaller particle sizes showed better protection efficiency compared to those of larger particles. The results were explained in terms of effective surface coverage by smaller sized SNPs.
This research work compares the chemical, nutritional and anti-nutritional compositions of shea nut (Vitellaria paradoxa) with cocoa (Theobroma cacao), and the effect of roasting on these properties. The ash, crude fibre, fat and carbohydrate contents of the two seeds showed some similarities, while the theobromine content of the sheanut was higher than that of cocoa. The mineral compositions of the two seeds were very low but the effect of roasting on the mineral content followed the same trend of increasing both the macro and micro elements contents of the samples. The anti-nutrient compositions of the two seeds were similar, with roasting having an increasing effect on the anti-nutritional factors (phytic acid, oxalate and tannin) when compared with the raw samples. The results revealed that sheanut will be a suitable substitute for cocoa in industrial applications.
The use of clay and its minerals in vegetable oil purification has been tremendous. It has been discovered that surface modification or activation of this distinct adsorbent greatly increases its adsorptive capacity. Similarly, seed hulls also known as carbonaceous materials are being used as the only adsorbent or combined with activated clays for vegetable oil bleaching. Prominent among the modification methods is acid activation. Acid activated clay minerals and carbonaceous materials have been used extensively as adsorbent industrially for vegetable oil bleaching. However, some challenges have been identified with the use of acid activated adsorbent for vegetable oil cleansing. This paper made a review of activation of clay minerals and carbonaceous materials and its effect on micro structure, surface area and bleaching efficiency in vegetable oil refining.