Characteristics of Gas Condensate

The characteristic features of Oso condensate and Delta condensate samples, including their gasoline potential, were determined using gas chromatographic integrator techniques. The analysis revealed that these condensate samples have recoverable gasoline of 41.65% wt and 49.82% wt., respectively. Both samples are from Cross-River and Delta regions of the Nigerian oil fields, respectively. Two other crude oil samples from the Delta region, Forcados and Bonny light, were also analyzed alongside the two-condensate samples for comparative study. These analytical results show that the two crude oil samples are less rich in light fractions than the condensate samples. The results of the analysis of the four oil samples lend support to the earlier report that Nigerian crude oils are mostly paraffinic in nature.     

Delineation of mineral potential zone using high resolution aeromagnetic data over part of Nasarawa State,North Central,Nigeria

Qualitative analysis of aeromagnetic data of part of Nasarawa State had been carried out with the aim of delineating mineral potential zone. The study area is bounded by Longitude 8.0°E – 9.0°E and Latitude 8.0°N – 9.5°N with an estimated total area of 18,150?km². Different filters were used to enhance the short wavelength anomalies which could give preliminary information about the magnetic minerals present in the study area. The total magnetic intensity map shows variation of both highs and lows magnetic signature ranges from ?51.2?nT to 110.4?nT after the removal of IGRF value of 33,000?nT; the highs which is basement dominates the north-eastern and north-western part of the study area which corresponds to Akwanga, Wamba and Nasarawa Eggon; these are areas with promising solid minerals of economic potentials like, gold at Wamba; Tin, Columbite and Tantalite at Akwanga while Granite rocks with possible radioactive elements are in abundance at Nasarawa Eggon. The low magnetic values on the other hand, which is made up of sediment deposition also dominates the southern part of the study area, this area corresponds to Lafia, Doma and Keana; Lafia and Doma host some industrial minerals like Clay, glass Sands and the Salt Brines at Keana. The major high magnetic signature trends east-west. The greenish part of the study area indicates alluvium deposition. The filters used are vertical derivatives, downward continuation and analytic signal. The first and second vertical derivatives; shows structures like lineament that could be the host to minerals present in the study area and it trends NE-SW. The downward continued at the depth of 50?m and 100?m shows the veins where magnetic minerals most especially gold are known to settle along igneous and metamorphic rocks. The analytic signal map shows that magnetic amplitude highs could be found at the northern end with most lineaments delineated also conform to other filter used. The tilt derivative map enhances short wavelength anomalies which could be used to mapped shallow basement structures and mineral exploration targets. The results of these filters agreed largely and since most magnetic minerals are structural controls, it is expected that those lineaments identified, most especially at the northern part, could play host to those minerals aforementioned.     

Genome Subtyping of Autochthonous Bacillus Species Isolated from Iru,a Fermented Parkia biglobosa Seed

Phylogenetic relationship and strains sub-typing of Bacillus species isolated from iru, a traditional fermented condiment in Africa were studied using polyphasic genomic approaches and the profiles compared with bacilli isolated from similar Asian condiments. The 16S rRNA gene sequencing identified the strains as Bacillus subtilis, Bacillus amyloliquefaciens, Bacillus cereus, Bacillus licheniformis, Bacillus pumilus, and Brevibacillus formosus. The phylogenetic analysis conducted showed five distinct clusters with genetic relatedness among B. subtilis and B. amyloliquefaciens strains from Africa and Asia. Amplified ribosomal DNA restriction analysis (ARDRA) successfully differentiated species of B. subtilis phylogeny from B. cereus. Combined analyses of ARDRA, internal transcribed spacer-polymerase chain reaction (ITS-PCR), ITS-PCR-restriction fragment length polymorphism (ITS-PCR-RFLP) and randomly amplified polymorphic DNA (RAPD-PCR) further confirmed B. subtilis and B. amyloliquefaciens as the dominant Bacillus species associated with fermentation of iru, and revealed high strains genetic diversity, while multilocus sequence analysis (MLSA) data distinguished B. cereus from B. thuringiensis. This information is essential for selection of starter cultures with desirable functional attributes to guarantee product consistency and safety quality of traditional fermented foods.     

FOSSES: Framework for open-source software evaluation and selection

A plethora of approaches exists for the evaluation and selection of open-source software (OSS) in the literature. However, these approaches are hardly ever used in practice for the following reasons: first, the lack of a situational-based procedure to define the evaluation criteria for OSS given its varied and dynamic nature; second, the inability of existing evaluation techniques, such as the analytic hierarchy process, to cope well with uncertainty factors, thus producing misleading results that affect the quality of decisions made; and third, a significant number of existing approaches require the prototyping of alternatives being considered in order to facilitate evaluation and decision-making. This study addresses the aforementioned challenges by evolving a process framework for evaluating and selecting OSS. The proposed framework is validated by applying it to a case study. In addition, expert opinion was elicited via questionnaires from 10 experts, and overall feedback suggests that 80% of them are willing to adopt the approach.     

Sun drying of cocoa with firebrick thermal storage materials

The thin-layer drying process of N38 cocoa beans using open-sun and a solar drying (SD) system with firebrick heat storage materials (FTSM) has been modeled. The 10 kg capacity force convective SD system was developed and used to carry out the experiments. The choice of the best model was based on a comparison of statistical indicators including determination coefficient (R²), reduced chi-square (χ²), root mean square error (RMSE), sum of square error (SSE), and normalized root mean square error (NRMSE) after fitting the experimental results to 11 common thin layer models in the literature. The results revealed that under open-sun drying and SD processes, the Midilli et al model provided the best drying characteristics of cocoa beans. Therefore, in the experimental context, this model can be assumed to reflect the solar/sun drying behavior of cocoa. The effective diffusivity values for the open-sun and SD of cocoa with FTSMA and FTSMB were 4.25× 10⁻¹¹, 6.64× 10⁻¹¹, and 5. 95 × 10⁻¹¹ m²/s respectively. The predicted pre-exponential factor and activation energy were 5.81 × 10⁻¹¹ m²/s and 22.79 kJ/mol respectively.