NEW RESULT ON A FLUID FLOW INDUCED BY A ROTATING MAGNETIC FIELD

This research paper provides a new result on induced fluid flow in a circular cylinder under the influence of a rotating magnetic field. Maxwell’s induction equation and asymptotic technique are used to obtain the new result and it is observed that the convective term which Mofatt neglected in his work is significant in the boundary layer

A SMART SYSTEM FOR MONITORING OIL PIPELINE INSTALLATIONS USING FIBER OPTIC SENSORS

Oil Pipeline installations are national infrastructures of high economic value. This makes monitoring and protection of such installations against the threat of economic saboteurs a national issue for any government. In this paper, a system for smart monitoring of oil pipeline using optical fiber cable is presented as a solution to the inadequacy of the traditional human and/or animal physical monitoring. The designed system employs fiber optic as sensor laid along the oil pipeline installation and a software that analyses the optical signal generated to determine the occurrence of threat to the installations. The smart system takes advantage of the effect of environmental phenomenon on optical signal traversing the optical fiber sensor in the automated monitoring of oil pipeline installations. On the basis of the mathematical relationship between light intensity and applied pressure, the system is able to determine (against a pre-set threshold), an attempt or the actual vandalization of oil pipeline installation

Hydrogen peroxide and lime based oxidative pretreatment of wood waste to enhance enzymatic hydrolysis for a biorefinery: Process parameters optimization using response surface methodology

Response surface methodology (RSM) was adopted for the optimization of process variables in the alkaline peroxide oxidation (APO) pretreatment of Vitellaria paradoxa sawdust based on central composite design (CCD) experiments. A 23 five level CCD with central and axial points was used to develop a statistical model for the optimization of process variables. Maximum response for the pretreatment was obtained when applying the optimum values for temperature (150 �C), time (45 min), and 1% (v/v) H2O2. At the optimum conditions, up to 70% of the initial hemicellulose was removed in treatments, which also caused some delignification (up to 11% of the initial lignin was removed), whereas cellulose was almost quantitatively retained in the solid phase. Alkaline peroxide assisted wet air oxidation (APAWAO) pretreatment at the optimum conditions resulted in enrichment up to 60% cellulose content along with solubilization of 80% hemicellulose and 17% of lignin initially present in the raw sawdust. Reducing sugars yield after 72 h enzymatic hydrolysis of pretreated biomass at optimized APO conditions was 177.89 mg equivalent glucose g�1 dry biomass. Addition of 10 bar air pressure at the optimized pretreatment conditions increased the sugars yield to 263.49 mg equivalent glucose g�1 dry biomass

The current pattern of facility-based perinatal and neonatal mortality in Sagamu, Nigeria

Background: Perinatal and neonatal mortality rates have been described as sensitive indices of the quality of health care services. Regular audits of perinatal and neonatal mortalities are desirable to evaluate the various global interventions. Objective: To describe the current pattern of perinatal and neonatal mortality in a Nigerian tertiary health facility. Methods: Using a prospective audit method, the socio-demographic parameters of all perinatal and neonatal deaths recorded in a Nigerian tertiary facility between February 2017 and January 2018 were studied. Results: There were 1,019 deliveries with stillbirth rate of 27.5/1000 total births and early neonatal death (END) rate among in-born babies of 27.2/1000 live births. The overall perinatal mortality rate for in-facility deliveries was 53.9/1000 total births and neonatal mortality (till the end of 28 days) rate of 27.2/1000 live births. Severe perinatal asphyxia and prematurity were the leading causes of neonatal deaths while obstructed labour and intra-partum eclampsia were the two leading maternal conditions related to stillbirths (25.0% and 21.4% respectively). Gestational age < 32 weeks, age < 24 hours and inborn status were significantly associated with END (p = 0.002, p <0.001 and p = 0.002 respectively). Conclusion: The in-facility perinatal mortality rate was high though stillbirth rate was relatively low. There is a need to improve the quality of emergency obstetric and neonatal services prior to referral to tertiary facilities

Modelling of sweet gas flaring and the resultant gaseous emissions with their emission factors

Data from literature and a stoichiometric material balance model were employed to estimate associated emissions with flaring of sweet gas in Nigerian oil and gas companies. Emission factors were obtained using AP 42 formula. Results showed that thousands of tonnes, ranging from 6500 to 22,000 tonnes of natural gas were flared from 1997 to 2016. At flaring stack efficiencies of 97% and 98%, the associated emissions are: CH4, C2H6, C3H8, iC4H10, nC4H10, iC5H12, nC5H12, C6H14, C7H16, C8H18, C9H20, CO2, and N2 from unburnt natural gas and in addition to CO2, CO, N2, NO, NO2, H2O and H2 from incomplete combustion. At both flaring stack efficiencies, the amount of emissions from unburnt condition ranged from1,608 tonnes N2 to 9,146 tonnes CO2 all higher than any emission standards in the world, while the amounts of emissions from incomplete combustion ranged from 467,964 tonnes for CO2 the lowest to 2,476,011 tonnes for N2 the highest all higher than any emission standards in the globe. Emission factors of emissions from unburnt natural gas ranged from 0.000090 tonne/tonne for C10H22 to 0.026235 tonne/tonne for CH4 while those of the emissions from incomplete combustion ranged from 0.10285 tonne/tonne for H2 to 1.13137 for CO2 tonne/tonne. It was observed that thousands of tonnes of emissions are released into the atmosphere during flaring of sweet natural gas either at complete or incomplete combustion. It is recommended that flaring of natural gas should be reduced to a minimal level to safeguard the environment

Efficiency of molecular markers to select for Striga gesnerioides resistance in cowpca [Vigna unguiculata (L.)Walp]

Striga gesnerioides (Willd) Vatke is a major biological constraint to cowpea productivity in the dl) savannas of sub-Saharan Africa. Over the last two decades, the use of molecular markers in crop improvemem has gained prominence owing to its ability to sh0l1en the breeding cycle. The available molecular markel techniques are being improved upon and continuously tested for higher preci sion, shOl1er duration of application and better cost effectiveness. [n the present study, a total of four molecular markers developed for selecting Slriga resistant cowpea were used to genotype F2 population derived from a cross between Borno Brown and [T97K-499-35 to identify markers more close ly linked to S. gesnerioides resistance. SSRI and 2 were found 10 be tight ly linked to Striga gesnerioides with a genetic distance of 1 and 2cM.The selection efficiency of SS~I and SSR-2 were 99 and 98 % and was better than that of C42-B 85.5%

Optimization of pretreatment conditions using full factorial design and enzymatic convertibility of shea tree sawdust

In this study alkaline wet air oxidation (WAO), alkaline peroxide assisted wet air oxidation (APAWAO), and enzymatic hydrolysis methods were evaluated for conversion of wood residue (sawdust) to reducing sugars. Cellulose content, hemicellulose solubilization, and lignin removal forWAOpretreatment conditions were optimized by statistical analysis using a 23-full factorial design with reaction temperature, air pressure, and reaction time as the process parameters. An optimum WAO condition of 170 �C, 1.0 MPa, 10 min was predicted and experimentally validated to give 518 g kg-1 cellulose content, 580 g kg-1 hemicellulose solubilization, and 171 g kg-1 lignin removal in the solid fraction. About 7 g L-1 reducing sugars was detected in the pretreated liquid fraction. Presoaking the dry raw biomass for 24 h in H2O2 followed by wet air oxidation (APAWAO) at the optimized conditions resulted in enrichment up to 683 g kg-1 cellulose content in the solid fraction along with solubilization of 789 g kg-1 hemicellulose and 280 g kg-1 lignin removal. The yield of reducing sugars from WAO optimized conditions by two enzyme preparations (cellulase and b-glucosidase) was 131mgg-1 of dry substrate, while the APAWAO yielded 274mgg-1. Pretreatments used in this study showed to have a disrupting effect on the lignocellulosic biomass, making the treated materials accessible for enzymatic hydrolysis. The combination of presoaking inH2O2 before WAO pretreatment and enzymatic hydrolysis was found to give the highest sugar yield

Evaluation of Methods for the Analysis of Untreated and Processed Lignocellulosic Biomasses

The overall efficiency of the transformation of lignocellulosic materials to usable products as chemicals and fuels must be governed by adequate analysis of products before and after treatments. Using some promising technologies, lignocelluloses which are biomasses from marine plant and trees, grains, food and non-food crops, and woodbased can give products as fuel alcohol and other chemicals. Various methods of transformation from feedstock to valuable end products are discussed in the scientific literature. Therefore, yields must justify methods used for biomass transformations. As a result, adequate compositional analysis of these processing stages is needed. In this chapter, standard common methods such as gravimetric, chromatography, spectroscopic and their variations for analysis on both untreated and treated lignocelluloses are highlighted. The ease of the use and challenges with recommendations to their applicability to quantifying lignocelluloses fractionations for reproducibility and to be representative are discussed. With biomass technology, virtually all and even more products that can be produced from fossil energy can also be produced from biomass energy. Adequate analysis is therefore necessary