Rivers State University of Science and Technology

About: Rivers State University of Science and Technology is a education organization based out in Port Harcourt, Rivers, Nigeria. It is known for research contribution in the topics: Population & Threatened species. The organization has 1826 authors who have published 1833 publications receiving 15183 citations.

A sustainable model for information and communication technology in Nigeria's tertiary educational transformation

Abstract: Information and Communication Technology (ICT) has revolutionalized and globalized all aspects of human endeavor. The effects of ICT in transforming the educational sector and contributions to the advancement of knowledge through teaching and learning is the rationale behind this study, which investigates the impact of ICT in transforming tertiary education in Nigeria. The study identified three key areas in addressing the transformation: expanding the access to teaching and learning; improving the quality of education; and making it affordable in terms of cost and time. A mixed methodology approach was adopted which involved the use of questionnaires and unstructured interviews administered on students and lecturers, using a case study survey strategy. A novel sustainable ICT model termed guided transformation was developed.

Predictive model for compressive strength of concrete made from recycled concrete coarse aggregates

Abstract: The objective of the study is to replace coarse natural aggregate with recycled concrete coarse aggregate (RCCA) for concrete production in order to determine the compressive strength of such concrete for different percentages of partial replacement using different water/cement ratios. Thereafter develop a predictive model for the compressive strength using different percentages of partial replacement and water/cement ratios. The polynomial regression model was applied to examine the correlation between the compressive strength of concrete, water cement ratio and %RCCA. The following regression models were established for 28 days at 0.4, 0.45 and 0.50 water cement ratio,f 28,0.4 = -0.000(%RCCA)²- 0.192(%RCCA) + 49.79 with R² = 1,f 28.0.45 = 0.000(%RCA )² - 0.371(%RCCA) + 44.29 with R² = 1, and f 28,0.50 = -0.001(%RCCA)² - 0.386(%RCA) + 41.91 with R² = 1. At 28days test for water cement ratios of 0.55, 0.6 and 0.65 as f 28,0.55 = -0.0001(%RCCA)² - 0.158(%RCCA ) + 38.26 with coefficient of determination of R² = 1, f 28,0.60 = 0.010(%RCCA )² - 0.1954 (%RCCA) + 28.29 with R² = 1, while for W/C ratio of 0.65 is given as f 28,0.65 = -0.001(%RCCA )² + 0.222(%RCCA) + 18.37 with coefficient of determination, R² = 1. It was concluded that the increase or decrease in compressive strength of concrete was dependent on percentage replacement ratio of natural aggregate to recycled concrete aggregate (%RCCA) and the amount of water to cement ratio (w/c) ratio of the mix. The significance of the study is that the compressive strength of concrete made with RCCA which is a waste product can be predicted by using the predictive model developed. Keywords : Concrete, Compressive strength, natural aggregate, Predictive model,Recycled concrete aggregate, Water/ cement ratio.

Accelerated Ripening Agents and Their Effect on the Quality of Avocado (Persia americana M.) and Mango (Mangifera indica L.) Fruits

Abstract: The natural process of fruit ripening is a combination of physiological, biochemical and molecular processes which can be activated or accelerated artificially by using different chemical agents. This study was carried out to examine the effects of three ripening process on the quality of avocado and mango fruits. Freshly unripe mango and avocado fruits were treated with calcium carbide powder, kerosene fumes and ripening in woven polypropylene bags. Calcium carbide treated fruits were stored for 48 hrs and all the samples were fully ripened except avocado fruit. The kerosene fumed fruits were stored for 24 hrs and then exposed to open air for another 24 hrs. Fruits ripened in empty plastic rice got ripened within 4 and 5 days for mango and avocado, respectively. The fruits were then analyzed for their physicochemical properties and sulphide and sulphate distributions using standard methods. The result revealed a decrease in TTA, pH, carbohydrate and vitamin C contents on ripening. On the other hand, moisture and TSS was observed to increase. However, accelerated ripening had no significant (p<0.05) effect on the moisture and Original Research Article Orisa et al.; AJAAR, 14(2): 29-40, 2020; Article no.AJAAR.59309 30 vitamin C content of the fruits. Mango samples treated with calcium carbide recorded higher acidity (0.92%) and low pH (3.08) than those treated with kerosene (0.29% and 3.71%, respectively). Sulphide and sulphate distribution of avocado was found to increase after accelerated ripening with kerosene fumes. A decrease for sulphate (outer distribution) and increase for sulphate (inner) and sulphide (outer) was observed for mango fruits. The results also showed that ripening in woven polypropylene had no significant (p<0.05) effect on the TTA of the fruits while pH, moisture and TSS varied significantly (p<0.05) with fruit type. The use of calcium carbide for fruit ripening is not advisable.

Long-Run Determinants of Nigerian Inflation Rate: ARDL Bounds Testing Approach

Abstract: Inflation is a problem in all facets of life and all economic entities. The government of any nation is concerned with ensuring that her plans are not frustrated by unpredictable and galloping prices. This paper studies the dynamic causal relationship between inflation rate (measured by consumer price index (CPI)), exchange rate, gross domestic product (GDP), money growth, and oil export in Nigerian during 2005: Q1 to 2019: Q4. The ARDL bounds testing approach and error correction model were used to verify whether there was a long-term relationship between the inflation rate and four determinants (exchange rate, GDP, money growth, and oil export). The results of our study showed that the current inflation CPI, the exchange rate, GDP, and money growth would still affect the next quarter's inflation rate in Nigeria. However, the oil export has no significant effect on the inflation rate. Moreover, we find the long-run cointegration relationship between inflation CPI, the exchange rate, and money. The cointegration relationship will be achieved in a short time (during the next two quarters of the year).