Evaluation of Geotechnical and Structural Performance of Cement-Stabilized Soil with Saw Dust Ash (SDA)

Availability of good soils for the construction of Civil engineering works is pivotal to the development and progress of any nation. Where good soils are lacking, it is necessary to make the soil fit through soil improvement methods. This study investigates the geotechnical performance of soil stabilized with the blend of cement and saw dust ash (SDA). The blend consists of 9% cement by weight and up to 10% of SDA at interval of 2%. The tests conducted on both stabilized and unstabilized soils samples at three different locations, identified as A, B, and C were: particle size distribution, natural moisture content, Atterberg’s limits, compaction, California Bearing Ratio (CBR) and Unconfined Compression Strength (UCS). The results showed decrease in plasticity index from high to medium, increase in CBR values: 4 – 10% for sample A, 2 – 12% for sample B and 5 – 8% for sample C, and increase in unconfined compression strength values: 45.23 – 65.88 kN/m2 for sample A, 34.01 – 59.18 kN/m2 for B and 41.80 – 63.94 kN/m2 for C. The results of this investigation showed that improvement of soil for construction purpose can be achieved when SDA is applied as a stabilizer in a cement-stabilized soil, up to 6% by weight of cement. Specifically, improved shear stress demonstrated up to 6% replacement is an indication of fitness for application of such soil in the design of footing, especially for columns, where shear stresses usually control the footing thickness

Nutritional Evaluation of Honey Bee Slum gum Meal as Replacement for Maize in the Feed of Growing Rabbits

As part of the efforts in developing alternative feed ingredients for feeding rabbits a feeding trial was conducted to investigate the nutritional potential of Honey Bee slum gum meal (HBSM) on the performance characteristics of growing rabbit. Thirty (30) growing rabbit of 7 weeks of age were weight-balanced and divided into three (3) dietary treatment groups of 10 rabbit each in a completely randomized designed experiment. Diet 1 had 0% inclusion of HBSM while 25 and 50% maize in diets 2 and 3 were replaced by HBSM respectively. Rabbits received feed and water ad libitum during the 12 weeks of the experiment. The final weights decrease linearly (P<0.05) as the level of inclusion increases (1663.20g 1630.00g and 1458.40g for rabbits on treatments 1, 2 and 3 respectively). Rabbit on diets 1 and 2 had higher (P<0.05) daily weight gains (13.59g and 13.15 respectively) compared with rabbits on diet 3 (11.1g). The digestibility of nutrients were not affected (P>0.05) by the dietary treatments. The values obtained for final weight, carcass weight, abdominal fat, kidney, liver and lungs were significantly (P<0.05) affected by dietary treatment. HBSM can be used as an alternative for substituting maize in growing rabbits diets up of 25% beyond which depression in performance is observed. Key words: Honey slum gum meal, Digestibility, Final weight, growing rabbits

Coal combustion models: a review

Abstract : Computational Fluid Dynamics has been used for optimisation of industrial applications with some level of success. The modest accuracy provided by some of the combustion models in use has left some room for research and improvement. Coal is presented as a fuel with complex chemical properties due to its fossil fuel nature. The devolatilization process of coal is investigated with special attention to the best models that can handle heavy and light volatiles found in coal. The heterogenous char combustion is also presented paying attention to the nature of the char particle during the combustion process. The other processes such as drying, homogenous volatile combustion, radiation models, particle tracking models and turbulent models are investigated in a general manner as they rarely vary with the type of fuel being investigated. A summary of the industrial applications that have successfully utilised the CFD models for optimisation of coal combustion are presented thus helping in drawing the final conclusion

Evaluation of Selected Cowpea Lines and Cultivars for Inherent Resistance against Cowpea Seed Beetle, Callosobruchus maculatus Fabricius (Coleoptera: Chrysomelidae: Bruchinae)

Four cowpea lines (IT99K-494-6, IT97K-390-2, IT84S-2246-4 and IT06K-141) obtained from the Genetic Resources Centre, International Institute of Tropical Agriculture (IITA), Ibadan Nigeria, one cultivar (Ife Brown) obtained from Institute of Agricultural Research and Training (IAR&T), Obafemi Awolowo University, Ibadan and two cultivars (Drum and Oloyin) obtained from Wazobia Market, Ogbomoso, Nigeria were screened for comparative susceptibility to the infestation of cowpea seed bruchid, Callosobruchus maculatus. The number of eggs laid on IT99K-494-6 (20.05) was significantly (p < 0.05) lower than the number laid on all the local cultivars (56.33-78.83). First filial progeny emergence (0.71) observed in IT99K-494-6 was significantly (p < 0.05) lower than 2.06 and 1.65 observed in Ife Brown and Drum cowpea cultivars, respectively. Percentage seed damage for 1T99k-49-6 (10.14) was significantly lower than the value obtained in 1T06K-141 (49.93) and Drum (47.74). Alkaloids content was significantly higher in IT06K–141 (31.67 mg/100 g) than in other lines and cultivars. Oloyin had the highest flavonoid (51.7 mg/100 g), tannins (43.3 mg/100 g) whereas 1T84S-2246-4 had the highest saponins (61.7 mg/100 g) Drum had the highest terpenoid (33.33 mg/100 g). Steroid was highest in Oloyin and 1T84S-2246-4 (11.67 mg/100 g). Reducing sugar was highest in Oloyin (5.33 mg/100 g) followed by 1T84S-2246–4 (4.3 mg/100 g) and IT06K–141 (4.0 mg/100 g). Significant and positive relationship exists between saponins content and the number of grains without exit holes (r = 0.46, p = 0.04), suggesting that high saponins was contributory to cowpea host plant resistance to the cowpea seed bruchid, C. maculatus. Keywords: cowpea cultivars, Drum, Oloyin, host plant resistanc

HOST PLANTS OF THE COTTON MEALYBUG, PHENACOCCUS SOLENOPSIS TINSLEY (HOMOPTERA: PSEUDOCOCCIDAE) IN THREE SELECTED TOWNS OF NIGERIA, AND ITS INFESTATION PATTERN

Reconnaissance surveys were carried out for field infestation of Phenacoccus solenopsis Tinsley from 2006 to 2010 in seventy five (75) vegetable gardens located in three (3) towns– Ogbomoso, Abeokuta and Ibadan in Nigeria. No cotton mealybug infestation was observed in Abeokuta and Ibadan, but twenty four (24) plants in 16 different families were observed as its hosts in Ogbomoso area. Of the 24 species, weeds constituted 45.8%, vegetables 29.1%, herbs 12.5%, cereals 4.2%, fruit trees 4.2% and pulse 4.2% each. Infestations started on the abasial leaf surface and advanced to the mid-ribs, petiole, young and succulent stems and buds. Corchorus olitorius and Amaranthus hybridus were the most susceptible of the trialled plant species with heavy root infestation in addition to that of the leaf. On heavily infested plants, certain ants were found together with P. solenopsis; on cowpea however, Aphis craccivora and the ants formed a complex with the mealybug on the flower buds. Of the three towns surveyed, P. solenopsis could be said to be restricted to backyard gardens around Ogbomoso at the moment. However, a nation-wide survey is very necessary now to determine the current status of the mealybug in Nigeria.Â

Performance evaluation of a plate encapsulated salt hydrate PCM mixed with a gel

Abstract : An alternative method of cooling is required to meet cooling demands and simultaneously decrease conventional energy consumption. The current research aimed to investigate the feasibility of using a phase change material (PCM) in the form of a salt hydrate mixed with a CSIR-developed gel for PCM based cold storage that used nighttime cold to cool ambient air during the day. The experiments were conducted over a time period of three hours between 12:00 pm and 15:00 pm in the afternoon. The total temperature drops were found to be 3.8, 2.9 and 2.6 degrees for air flow rates of 0.03, 0.05 and 0.06kg/s respectively. The total energy transferred for each of the mass flow rates averaged 140.9, 144.4 and 158.9J for air flow rates of 0.03, 0.05 and 0.06kg/s respectively

Thermal Evaluation of Some Locally Sourced Activated Carbons from Agricultural Residues

Activated carbons are progressively used as an economical and stable mass separation agent for eliminating surfactants to raise the final product property in many industrial processes. Activated carbon has various applications in different fields, and it performs differently at different temperatures; hence this paper presents a thermal experimental characterization of some locally produced activated carbon from agricultural residues. The experiment was done on the locally produced activated carbon from coconut shell, coconut husk, palm kernel shell, maize husk and imported activated carbons. The adsorbate used is Methylene Blue (MB), the samples were agitated in a water bath shaker at different concentration of adsorbate (50, 100, 150 and 200 ppm) and different temperatures (30 oC, 40 oC, and 50 oC). Adsorption isotherm study is carried out on two well-known isotherms; Langmuir and Freundlich isotherm models. The results revealed that the adsorption capacity of the five samples increased with temperature and initial dye concentration. The adsorption in the samples follows the Langmuir Isotherm model that implies homogenous adsorption and Maize husk has the highest monolayer adsorption capacity at 40 oC. Hence the carbons will perform satisfactorily under heat as the combination of adsorbent and adsorbate in adsorption refrigeration system. The locally produced activated carbons compared favourably with imported activated carbon, hence locally produced activated carbons can replace imported activated, to reduce dependency on foreign product and improve the economy of the country. Keywords: Evaluation, Activated carbon,Adsorption Isotherm, Agricultural Residue

Awareness and knowledge of the sustainable development goals in a University Community in Southwestern Nigeria

Background: The Sustainable Development Goals (SDGs) is a globally  accepted developmental agenda, and it is expected that everyone everywhere in the world would be aware, knowledgeable and be willing to contribute to its  attainment. This study aims to assess the level of awareness, knowledge of, and attitudes towards the SDGs among members of a university community. Methods: A cross-sectional survey was conducted on 450 students and staff of Osun State University, Southwestern Nigeria, selected from three of its six  multi-campuses via multi-stage sampling. Data were collected by means of  semi-structured questionnaire. Data were analysed using SPSS version 20.0. Results: The mean age for the respondents was 26(10.2) years. Only 43% of the respondents were aware of the SDGs and only 4.2% had good knowledge of the SDGs. However, 56.3% had positive attitude towards it. More respondents with good knowledge of the SDGs were either acadenic staff or those have been  enlightened via personal study of the SDGs or through other means. Similarly having a positive attitude was associated with being an academic staff/ high level of education as well as belonging to the middle age group. (p<0.05). Conclusion: The awareness of and attitudes towards the SDGs was just fair. However, the level of knowledge was abysmally low, and this has serious  negative implications for SDGs attainment. Pertinent individual and  population-level methods of enlightening people about the SDGs must be put in place in educational settings; curricular changes are imperative. Keywords: Attitudes, Awareness, Knowledge, MDGs, SDGs, University

Antioxidant and Hepatoprotective Potentials of Lemon Juice and Sorghum Ogi (lemon-ogi) Mixture against Paracetamol-Induced Liver Damage in Rats

This study is aimed to determine the hepatoprotective activity and antioxidant properties of aqeous extract of Sorghum porridge (Ogi), a Sorghum fermentation product, mixed with lemon to form Lemon-Ogi mixture at various concentrations after inducing liver injury in rats. Rats were divided into 9 groups (n=4) the positive control group, negative control group, normal control and the treated groups (which include extracts at varying concentrations between 0-50% v/v). Hepatotoxicity was induced in rats by oral administration of paracetamol (1 g/kg body weight) suspended in normal saline on the first day of the experiment. After 7 days of post-treatment with the test mixture (Lemon-Ogi), biochemical markers such as L-aspartate aminotransferase (AST), L-alanine aminotransferase (ALT), Gamma Glutamyl transferase (GGT) were estimated. This was followed by the measurement of liver cytosolic antioxidant enzymes such as superoxide dismutase, catalase, and peroxidase. The data were analyzed using one-way analysis of variance (ANOVA) followed by Duncan post hoc test. The test mixture at concentrations of 30-50%v/v significantly (P ≤ 0.05) reduced the elevated levels of AST, ALT, GGT when compared with the negative control animals. The Lemon-Ogi mixture also showed a significant (P ≤ 0.05) increase in the reduced levels of superoxide dismutase (SOD), catalase, and peroxidase when compared with the negative control. The effects of the Lemon-Ogi mixture on these parameters were comparable with those of the standard drug, Vitamin E at 50% (v/v) concentration. The findings of this study indicate that Lemon-Ogi mixture showed a potential hepatoprotective activity and the protective action might have manifested by restoring the hepatic SOD, catalase, and peroxidase levels. The results of this study validate the traditional use of Sorghum porridge steep water as a strong antioxidant. Keywords: Paracetamol-Hepatotoxicity, Biochemical Marker Enzymes, Antioxidant Enzymes, Lemon, Og

IMPACTS OF COAGULANTS ON QUALITY OF SOFT CHEESE PRODUCED FROM COW-SOY MILK BLENDS

Production of cheese at household level involved the use of different locally produced coagulants which include alum, Sodom apple and fermented maize liquor. Their effects on quality of cheese made from blends of cow-soy milk are sparse. This work investigated effect of coagulants on soft cheese produced from cow soy blends. Soft cheese samples were produced from cow-soy milk blends (90:10%). The cheese was coagulated using three locally available coagulants {juice of Sodom apple (Calotropis procera), aqueous solution of Potassium alum and fermented maize liquor}. Samples were analysed for yield, pH, proximate and mineral contents. Microbial analysis and sensory attributes were also determined. The yield obtained ranged from 38.7 to 39.0%. Highest yield was obtained from Sodom apple coagulated cheese sample. Cheese produced using fermented maize liquor had the highest pH (6.07) while Sodom apple and alum coagulated cheese had the pH values of 6.83 and 6.97, respectively.  The moisture contents of the produced cow-soy cheese ranged from 70.4 to 73.57%. The protein content of the cheese samples coagulated with alum had the highest (12.97%) in all the samples. There was no fiber in all the cheese samples produced. Calcium contents obtained from the three samples ranged between 171.67 and 185.00 mg/100 g. The iron content of cheese coagulated with fermented maize liquor (3.63 mg) was significantly (p < 0.05) higher than that of alum coagulated (3.23 mg/100 g) and Sodom apple coagulated cheese (3.33 mg/100 g). Higher microbial load was recorded in cheese samples coagulated with FML. The sensory attributes of the cheese samples varied with different coagulants. This indicates that the type of coagulant used in cheese-making has effect on the yield, pH some nutritional and sensory attributes of cheese