Nigerian Journal of Technological Research

Assessment of epiphytic algae community as bioindicator of organic pollution: A case study of Orokubu Creek, Bille, Rivers State, Nigeria

2022-12-21T06:35:04+00:00

Orokubu Creek, Bille, is a tidal estuary and tributary of the Centre of the New Calabar River, Niger Delta receiving organic anthropogenic effluents. The study investigated epiphyton assemblage from July to December 2019. Samples were collected from three stations (Frey-Boko, Oruama-Boko and Okpologio) and preserved. Epiphyton samples were identified microscopically. Phosphate (PO₄), Sulphate (SO₄) and nitrate (NO₃), were analyzed in the laboratory. PO₄ recorded (3.39±0.25 mg/L), SO₄ (457.34±20.47 mg/L), NO3 (4.33±0.19 mg/L) and total organic carbon (2.46±0.16 mg/L). Phosphate and Sulphate were higher than 0.1 mg/L, and 100 mg/L recommended international standard. A total of 5 families, 28 genera and 70 species of periphyton assemblage were observed [Bacillariophyceae (16.83%), Chlorophyceae (26.85%), Cyanophyceae (22.81%), Pyrrophyceae (27.43%) and Chrysophyceae (6.08%)] at p<0.05. Bioindicator species found were Raphidiopsis Mediterranea, Phormidiaspp, Microcystis aeruginosa, Nitzschia sigma N. lanceolate N. acicularis, Navicularostellata, Cyclotella comta (Bacillariophyceae), Anabaena spiroides, A. planctonica, Lyngbyahieronymusii, (Cyanophyceae) and Gonyaulaxpolyhedra, Gymnodinium catenatum, G. breve, Prorocentrummican, P. reiculatum (Pyrrophyceae). Bacillariophyceae correlated positively with nitrate. High levels of phosphate and nitrate showed the study area is organically polluted. The polluted wastewater contains detergents used in washing clothes, badges, bunker hose, faecal deposit, gas flaring, illegal local refinery ovens waste and decayed organic log woods. The study, therefore, suggests regular monitoring of the surface water and epiphyton community of Orokubu Creek because of the various industries and houses around this creek.

Germination patterns of some selected savannah seeds using various pre-sowing methods to assess seedlings growth responses in nursery

2022-12-21T06:40:57+00:00

The study was carried out at Forest Nursery, Federal University Dutsin-Ma to evaluate germination patterns of some savannah seeds using various pre-sowing methods to assess growth responses in nursery. The experiment was laid out as 5 x 5 factorial in Randomized Complete Block Design (RCBD) with four replicates. The factors were; agroforestry tree seeds (AFTS); Acacianilotica (AN); Parkiabiglobosa (PB); Diospyrosmespiliformis (DM^k); Detariummicrocapum (DM^t); Adansoniadigitata (AD) and pre-sowing treatments; Seeds soaked in 60 % diluted Tetraoxosulphate (VI) acid (H₂SO₄) (A); mechanical scarification (Ms); hot water at 60° C (HW); seeds soaked in water for 24 hours (W); control (C). The data were analyzed using ANOVA at p = .05. Seed emergence started 6 days after sowing (DAS) in AN seed treated with H₂SO₄ for 5 minutes (AAN) and DM_k seeds soaked in water for 24 hours (WDM_k). AN seed soaked in H2SO4 for 5 minutes (AAN) and DM_t seeds soaked in H₂SO₄ for 5 minutes (ADM_t) gave the highest (60 % and 50 %) germination percentage respectively. AN and DM_t seeds showed consistent significantly higher values (76.55, 187.50, 232.07, 325.50 and 506.05 and 0.34, 0.55, 0.63, 0.70 and 0.73) on number of leaves (NL) and collar diameters (CD) both at 2-10 WAS. A and W had significantly higher values (0.43, 0.50, and 0.56) and (0.40) on CD at 6-10 WAS and 4 WAS. In conclusion, AN and DM_t were the best performing seeds, AAN were the best pre-sowing treatment. They are therefore recommended for forest improvement and establishment.

Development and validation of correlations for liquid and vapour enthalpies and procedures for generating saturated vapour pressure for NH₃–H₂O solution

2022-12-21T07:07:08+00:00

Liquid and vapour enthalpies and saturated vapour pressure correlations were developed using the Chebychev series approach to curve fitting for the liquid and vapour phases of NH₃–H₂O(ammonia-water) solutions using experimental data. The average percentage deviations of the compared values were significantly low (±0.73925 for the liquid phase enthalpies, ±1.596 for the vapour phase enthalpies and ±0.513 for saturated vapour pressures). Therefore, the correlations derived can be used to calculate the Liquid and vapour enthalpies of NH₃–H₂O solution. Furthermore, data generated for the two phases were compared with values generated from the commonly used models of Patek and Klomfar (1995). While data generated for the liquid phase enthalpies were comparable for the two procedures (±0.08805 percentage deviation), the same conclusion could not be reached for the vapour phase as the deviation of calculated enthalpies from the model developed in this work increased with an increase in temperature. Since the generation and comparison of vapour enthalpies requires saturated vapour pressure values of the NH₃–H₂O solution, the paper has inadvertently provided a corresponding procedure and correlations for calculating this property. The paper further identified temperature and NH₃–H₂O concentration ranges that generate reliable enthalpies values for the three properties.

Determining the predictive model for drying characteristics of ripe plantain (Musa paradisiaca) slices using thin-layer models

2022-12-21T09:47:48+00:00

Vegetable drying is the most effective method for preserving agricultural products and is an energy-intensive process. The study investigated the effects of temperature and slice thick-ness on the moisture diffusivity effectiveness and the activation energy on dehydration kinetics of ripe plantain (Musa paradisiaca). Different slice thicknesses (3 mm, 4 mm and 5 mm) in a thin layer using a laboratory-convective oven dryer multiples of 10°C in the temperature range of 60 to 80°C were chosen and used. A suitable estimating thin-layer model was selected by fitting the results to the three thin-layer models of Lewis, Henderson, and Page. The parameters R², RMSE, and X², were used. It was observed that Henderson model R² ranged from 0.9064-0.996, RMSE ranged from 0.021838-0.000346 and X² ranged from 0.0017765712-0.0000000447730. Slice thickness increases with activation energy, and temperature increases with an increase in effective moisture diffusivity. As a result, the statistical analysis revealed that the Henderson model provided a reliable prediction for the drying characteristics of ripe plantain slices at the selected temperatures without a constant rate period but with the observed falling rate period.

Effect of periwinkle shell on the physical and mechanical properties of sandcrete block

2022-12-21T09:21:52+00:00

Periwinkle shells are waste products derived from Periwinkles. They can be recycled and processed either as fine aggregate, coarse aggregate, filler, or cement replacement. This study investigates crushed periwinkle shells' suitability as an alternate material for natural sand in sandcrete hollow blocks for sustainable infrastructure. Tests, including the chemical compositions and physical properties of the natural sand and periwinkle shells aggregate materials, were investigated. In addition, mechanical properties such as compressive strength, density, and water absorption of the sandcrete blocks using periwinkle shells as a replacement for sand at 5%, 10%, 30%, and 50% were evaluated. The result of 28 days compressive strength of sandcrete hollow blocks showed that 5%, 10 %, and 30% periwinkle shell partial replacement met the minimum requirement recommended for compressive strength for non-load bearing blocks by Nigeria Industrial Standard (NIS 87: 2000) specification. Also, 28 days bulk densities result of sandcrete hollow blocks ranged between 1860.97 and 2008.10 Kg/m3. The water absorption tendency of the sandcrete blocks reduces as the dosages of periwinkle increase from 0 to 30%. Utilising periwinkle as a replacement for fine natural aggregate will enhance green products' promotion for sustainable infrastructure and reduce the periwinkle pollution menace. Maximising waste periwinkle shells will foster the actualisation of the United Nations Sustainable Development Goals.

Evaluation of process parameters in the production of ethanol from agricultural waste

2022-12-21T09:25:48+00:00

The effect of temperature at which hydrolysis took place, hydrolysis and incubation times on percentage yield of ethanol using sawdust as biomass was investigated in this study. The collected sawdust was pretreated by soaking it in NaOH for 2 h and then boiled for 1 h at a temperature of 100°C. Enzymatic hydrolysis was thereafter carried out on the pretreated substrate by varying hydrolysis temperature (30-40°C), hydrolysis time (60-300 min). Thereafter, Saccharomyces cerevisiae was used for saccharification and fermentation which took place concurrently at varied incubation time (1-5 days). Box-Behnken design (BBD) in response surface methodology (RSM) using Design-Expert software was used to model and optimize the yield of ethanol using the selected process parameters. The production of ethanol from sawdust was positively influenced by all three process parameters. The optimum ethanol yield was 2.247 % at hydrolysis temperature, hydrolysis time, and an incubation time of 41.642 °C, 199.184 min and 3.546 days respectively. The very close values of the ethanol yields by the model and by the actual experiment performed at the optimal conditions validated the model.

Aquatic macrophytes diversity and distribution: a case study of Ifewara Reservoir, Osun State, Nigeria

2022-12-21T09:30:02+00:00

This study determined the species composition, diversity, distribution, spatio-temporal variations and community structure of macrophytes community in Ifewara reservoir, Osun State, Nigeria. Samples were collected from ten stations established over the three main basins of the reservoir (upper-flow, middle and lower basins). At each sampling station, plant species were collected and identified following standard procedures at the IFE Herbarium. The generated data were subjected to Clustal analysis, Principal Component Analysis (PCA) and Analysis of Variance (ANOVA). A total of 22 macrophytes species which belong to 17 genera and 13 families were recorded. The most dominant family was Onagraceae, which comprised four species. About two-thirds (65.2%) of the macrophtyes were of emergent form, with 30.4% as floating form, and 4.3% as submerged form. Azolla pinnata, Wolfia microscopica and Lemna minor were recorded only during the dry season with a record of about 22 species. PCA and Cluster analysis revealed a high correlation between upper and lower basins. The highest mean occurrence of 45.3±6.4% was recorded in the upper basin of the reservoir. The study concluded that the macrophytes community of the Ifewara reservoir was fairly diverse and most species were widely distributed.

Economic analysis of smoked – dried fish marketing in Akinyele Local Government Area of Oyo State, Nigeria

2022-12-21T09:33:50+00:00

Increased production of fish without increase in processing and marketing may lead to wastage of resources; therefore this study examined the economics analysis of smoked dried fish marketing in Akinyele LG, Oyo state, Nigeria. Multi-stage random sampling technique was used in data collection which was analyzed by descriptive and inferential statistics. The majority (90%) of the respondents were female with a mean age of 38 years; about 70% of the respondents were married and had formal education with an average household size of six persons. The majority did not belong to any marketing cooperative. The marketing margin was estimated at 42.43%, the gross margin profitability was N 913,000 per annum and the Benefit Cost Ratio was N 1.5. Major constraint include lack of capital, poor storage facility, poor transportation network while the size of production, cooperative association and educational level had a positive effect on the profitability of smoked fish marketing. Thus, marketers must form cooperative societies to get access to credit loans thereby increase profit. Also, provision of improved infrastructure such as modern processing equipment, good road network to increase the profitability of the marketers.

Investigation into the flow and stabilization of Cu-water and Cu-Gallium magneto nanofluid in a porous media

2022-12-21T09:40:46+00:00

The Rayleigh-Benard stability in liquid-metal nanofluids is investigated with somewhat emphasis on the behaviour of Brownian motion and thermophoresis of copper Cu nanoparticles. The critical Rayleigh number of the Cu-Ga decreases in not less than one order of magnitude as the modified magnetic Chandrasekhar number increases than that of the Cu-water nanofluids in Darcy and Darcy-Brinkman porous media. The Chebyshev spectral technique is used to resolved the resulting rigid-rigid boundary eigenvalue problem considered numerically. The numerical experimental results obtained for the effects of the modified magnetic Chandrasekhar number ?, Nanoparticle Rayleigh number ??, modified diffusivity ratio ??, modified specific heat increment ??, Lewis number ??, Darcy number ?? and porosity ?on the stabilization of both the water-based and liquid-metal based nanofluids with copper nanoparticle- results for Cu-water and Cu-Ga are presented graphically and tabularly.

Biochemicals extraction for sustainable feedstocks from dried leaves of Gmelina arborea

2022-12-21T09:46:15+00:00

Research on biomass for the production of biochemicals is getting more attention to find suitable feedstocks for our industries capable of replacement of petrochemicals that are not only hazardous to our environment but with diminishing sources. In this study, 50g of pulverized dead waste dried Gmelina arborea leaves were hydrothermally extracted with 500 mL of distilled water over 0.5, 0.75 and 1.5g of ZnCl₂ catalyst yielded 266 - 274.2g of fatty acids, 7.8 -18.5g 3-methyl butanol, 11.13 -16.09g furfural, 23.45 -26.32g α-farnesene, 20.8 -29.47 eugenol, 20.8 -25.26g phytol and 10.63 – 14.07g spathulenol. This method seems to be the cheapest for the production of biodiesel feedstock and feedstocks for food, agrochemicals, pharmaceuticals and cosmetic industries.