An Assessment of Wetland Loss in Lagos Metropolis, Nigeria

Wetlands are a very important subsystem of the general ecosystem as they play vital roles in the sustenance of both the surface and groundwater resources of the earth. However, much of the world’s wetlands have been lost due to series of human activities which gradually cause the degradation of this distinct element of ecosystem. The foundation of this problem is based on public perception of wetlands as unproductive, unhealthy lands, full of disease carrying insects and reptiles such as snakes and crocodiles. Therefore, this study assessed the loss of wetlands in Lagos metropolis. Questionnaires were administered on 75 Estate Surveyors and Valuers located within the study area and 76% were successfully retrieved. Also, 20 questionnaires were administered on conservation officials while 50% were retrieved. Data collected was collated and anlysed using descriptive statistics and relative importance index (RII). The study revealed that wetlands in Lagos Metropolis are habitats for fishes, source of water supply, help in sustaining the food chain of various wetland animals and are inevitably useful in maintaining the integrity of the Lagos coastline. The study further revealed urbanisation as a major factor responsible for the loss and degradation of wetlands in Lagos. Construction activities such as sand-filling, converting and reclaiming wetlands for the purpose of housing construction and infrastructural development contribute to wetland loss in Lagos metropolis. The study therefore concluded that efforts should be geared towards giving this natural ecosystem its due consideration when taking economic decision that will impact on it. Keywords: Environment, Lagos Metropolis, Wetland Loss, Wetland Valuation, Nigeri

Effects of Sodium Iso-butyl Xanthate Dosage on The Froth Flotation of Bead Milled Middle Group 1-3 PGM Ore Blend

An investigation was carried out to determine the effects of collector concentration on the grade and recovery in the flotation of middle group 1-3 Platinum Group Metal (PGM) ore mixture. The ore mixture pulp at a relative density of 1.29 was subjected to “bead milling”  test, particle size distribution analysis  and the 55% passing 75 µm was froth floated at 180, 200 and 220 g/t dosages of sodium isobutyl xanthate (SIBX) and 30 and 80 g/t of Senfroth and Sendep 30D frother and depressant, respectively. The results obtained indicated the predominance of the 38 µm PGM values in the ore and confirmed the need for tertiary milling for better liberation of the PGMs. The grade of the PGM concentrate obtained when dosing at 200 g/t of sodium isobutyl xanthate was highest at 94 g/t and gave the lowest recovery of 53%. The 180 g/t SIBX dosage resulted in highest PGM recovery of 70% and lowest grade of 84 g/t, while dosing at 220 g/t SIBX gave average PGM grades of 90 g/t  and  recoveries of 60%. The results obtained thus showed that that an SIBX dosage of 180 g/t SIBX would be appropriate when higher recoveries are targeted, while 200 g/t dosage will yield higher grade

Effects of Sodium Iso-butyl Xanthate Dosage on the Froth Flotation of Bead Milled Middle Group 1-3 PGM Ore Blend

An investigation was carried out to determine the effects of collector concentration on the grade and recovery in the flotation of middle group 1-3 Platinum Group Metal (PGM) ore mixture. The ore mixture pulp at a relative density of 1.29 was subjected to “bead milling” test, particle size distribution analysis and the 55% passing 75 µm was froth floated at 180, 200 and 220 g/t dosages of sodium isobutyl xanthate (SIBX) and 30 and 80 g/t of Senfroth and Sendep 30D frother and depressant, respectively. The results obtained indicated the predominance of the <38 µm PGM values in the ore and confirmed the need for tertiary milling for better liberation of the PGMs. The grade of the PGM concentrate obtained when dosing at 200 g/t of sodium isobutyl xanthate was highest at 94 g/t and gave the lowest recovery of 53%. The 180 g/t SIBX dosage resulted in highest PGM recovery of 70% and lowest grade of 84 g/t, while dosing at 220 g/t SIBX gave average PGM grades of 90 g/t and recoveries of 60%. The results obtained thus showed that that an SIBX dosage of 180 g/t SIBX would be appropriate when higher recoveries are targeted, while 200 g/t dosage will yield higher grade

APPLICATION OF LINEAR PROGRAMMING MODEL TO UNSECURED LOANS AND BAD DEBT RISK CONTROL IN BANKS

Most banks fail as a result of mismanagement of credit risk. In this paper, the management of credit risk as it affects loan portfolio management and proactive strategy to seek out relative value opportunities are considered. An operational research technique, linear programming, is applied to the management of loan portfolio of banks. With the results obtained, using Simplex method, an answer is provided to the question of how to avoid possible occurrence of non-performing loans, bad and doubtful debts in banks when some percentage of the loans they give out are not secured

A Stable and Consistent Finite Difference Scheme for a Time-Dependent Schrodinger Wave Equation in a Finitely Low Potential Well

In this paper, we present a stable and consistent criterion to an explicit finite difference scheme for a time-dependent Schrodinger wave equation. This paper is a departure from the well-established time independent Schrodinger Wave Equation (SWE). We do this for a particular case of a finitely low potential wel

The Effect of Nucleotide Transfer from Some Microbes to Improve Plants for Biotechnological Advancement

The advance in plant biotechnology has some challenges with the evolutionary trend and methods adopted to resolve some of these problems: to improve the host morphological and genotypic features by nucleotide alteration leading to changes in mitochondrial molecular structure in the eukaryotic and prokaryotic plants. However, some biotechnological designs used in this research are DGGE, Phoretix 1D, and the Shannon-wiener index (H). While the microbial DNA concentration,&nbsp; virulent qualities coupled with the adaptative features of both the microbes and host plant and bioactive compounds reduction effects on the transformed host plant were the findings from this research

On a Block Integrator for the Solution of First Order Ordinary Differential Equations

An efficient one step Adam type implicit block numerical algorithm developed by simultaneous employment of interpolation and collocation techniques is proposed in this paper. Non mesh points were introduced to upgrade the order of consistency and improve the rate of convergence of the method. Further analysis revealed a wide interval of absolute stability. The method is implemented as a block to improve efficiency and reduce computational cost. Comparison of the new method with previous methods in terms of absolute errors of approximation established an improvement over those methods

Conjugate Gradient Method Approach to Multi-Channel Queuing Theory

In this paper we examine the application of the classical conjugate gradient method to queue theory. The parameters of the symmetric definite positive linear operator of a quadratic cost functional were obtained from the various characteristic features of a multi-channel queue system. The outcome was tested with numerical values and a comparison was made for systems with two, three and four service points. The numerical computations were carried out in a Maple 14 environment. The results obtained validate previous work done with a single-channel syste

Influence of Torrefaction on Lignocellulosic Woody Biomass of Nigerian Origin

Torrefaction process is a thermal treatment that can improve quality of lignocellulosic biomass into a carbon-rich and hydrophobic feedstock which is applicable as fuel and metallurgical reductant. Biomass (Melina and Teak wood) of Nigerian origin was subjected to mild (240o C) and severe (300o C) torrefaction treatment at different residence times (30 and 60 min) and particle sizes (+0.5 - 2 mm and +4 - 6.35 mm). Raw biomass and biochar from torrefaction were subjected to proximate, ultimate, higher heating value and SEM analyses. The mass yield obtained for mild treatment conditions for both biomass was in the range of 72 - 84 (wt. %) compared to 40 - 54 (wt. %) under severe treatment conditions. However, 33 - 56 % increment in higher hating value was observed for severe treatment conditions as against 11 - 17 % of mild treatment condition. This ultimately led to a 60 - 72 (wt. %) energy yield for severe treatment conditions and 73 - 94 (wt. %). The fixed carbon content increased from the range of 8 - 11 (wt. %) to 20 - 61 (wt. %) after torrefaction. The volatile matter content under mild condition was reduced by 7 - 10 % for both biomass as against 41 - 47 % under severe treatment condition. The fuel ratio increased from 0.11 and 0.15 for Melina and Teak woods respectively to a range of 0.22 - 0.25 for mild treatment conditions and 0.97 - 1.75 for severe treatment condition. The H/C and O/C atomic ratios of biochar were lowered towards that of sub-bituminous coal and peat. A honey-comb-like structure with cylindrical holes were observed for biochar compared to the fibrous and spongy nature of the raw biomass. Biomass of Nigerian origin were improved under torrefaction and thus can be suitable as feedstock in thermal or metallurgical applications