Nigerian Society of Physical Sciences

Joseph Folake Lois , Olagunju Adeyemi Sunday, Adeyefa Emmanuel Oluseye, James Adewale Adeyemi,

Abstract

In this work, an orthogonal polynomial with weight function w(x) =x² + x + 1 in the interval [-1, 1] was constructed and used as the basis function to develop block methods, using collocation and interpolation approach. An efficient class of continuous and discrete numerical integration schemes of implicit hybrid form for third-order problems were developed and successfully implemented. Three different problems were solved with these schemes and they performed favourably. The investigation, using the appropriate existing theorems, shows that the methods are consistent, zero-stable and hence, convergent.

Dairo O. F., Willoughby A. A., Sanyaolu M. E., Osinowo M. O., Soge A. O.,

Abstract

A data acquisition system that utilised the open-source Arduino platform was developed to take real-time ground measurements of primary radio climatological variables of pressure, temperature, and relative humidity at Ede, a tropical station in southwest Nigeria (7.7349^{o} N, 4.4439^{o} E). Surface radio refractivity was deduced from these variables and used to estimate refractivity gradients at 100 m and 1000 m heights from the exponential reference atmosphere model for terrestrial propagation. Secondary radio propagation parameters such as refractivity gradients, the effective-earth-radius-factor, k, and geoclimatic factor, K, essential parameters for quick application in the planning and design of line-of-sight radio link systems, were also deduced. Data acquired from the device were compared to those obtained from the Re-Analyses (ERA-5) satellite database of the European Centre for Medium-Range Weather Forecast (ECMWF) 2020/2021. Aside from logging data on a micro secure digital (SD) card, measurements were displayed on a liquid crystal display (LCD). The peripheral Arduino-compatible meteorological sensors were connected to the analog inputs of the ATMega328 in the Arduino independent development environment (IDE), and the unit was powered by a 12 V battery charged by a 50-watt solar module. Results showed that slightly higher values of the ERA-5 data characterise the dry months from November to March, while the wet months displayed higher values of the Arduino-derived measured data. The accuracies of the data collected were compared using Mean Percentage Error (MPE) performance indicator. The interpretation is that the mean difference between the Arduino inferred measurements and the ERA-5 data is less than 10%, which is an indication of the measurement accuracy.

Wahab O. T., Usamot I. F., Alata S. M., Tijani K. R. ,

Abstract

In this paper, we introduce nonexpansive and expansive semigroup of order-preserving total mappings (ONT_n) and (OET_n), respectively, to prove some fixed point theorems in waist metric spaces. We examine the existence of mappings that satisfy the conditions ONT_n and OET_n. We also prove that every semigroup of order-preserving total mappings OT_n has fixed point properties and that the set of fixed points is closed and convex. The present study generalised many previous results on semigroup of order-preserving total mappings OT_n. Efficacy of the results was justified with some practical examples.

Ogunyemi B. T., Ojo F. K.,

Abstract

The potentials of six thiosemicarbazide derivatives towards corrosion inhibition were investigated theoretically using density functional theory (DFT) and quantitative structural-activity relationships (QSARs) methods. Their performance as corrosion inhibitors were evaluated using their calculated quantum chemical parameters such as molecular weight, softness, electronegativity, dipole moments, hardness, bandgap energy (\Delta E), highest occupied molecular orbital energy (EHOMO), and the lowest unoccupied molecular orbital energy (ELUMO). Regression analysis was carried out using the ordinary least square method to develop a model that establishes the relationship between chemical parameters and inhibition efficiencies that have been measured experimentally. According to the results, quantum chemical parameters confirm the inhibition potential of TSC5 to be greater than TSC2, while the predicted inhibition efficiencies of the studied thiosemicarbazide derivatives correspond to experimentally reported values with a root mean square error (%) of 1.116 and correlation coefficient of 0.998. The high correlation demonstrates and validates the quantum chemical approach’s reliability in studying corrosion inhibition on a metal surface. The validation of the developed model internally and externally demonstrates that it is robust and stable, with high predictability

Oluwayemi M. O., Onate C. A. , Okon I. B.,

Abstract

The relativistic symmetries of the Dirac equation were investigated with an energy-dependent tensor potential interaction for two different energy-dependent potentials under parametric Nikiforov-Uvarov method and supersymmetric quantum mechanics and shape-invariance method. It is observed that the energy-dependent tensor interaction has stronger removal effect of the energy degeneracies in both the spin and pseudospin symmetries than the non-energy-dependent tensor interaction.

Ajaelu C. J., Ikotun A. A., Faboro E. O., Oyedele O.,

Abstract

The availability of potable water has decreased in recent times due to the extensive discharge of effluents from some industries. This contaminated water poses a great danger to both human and aquatic life. Senna fistula was activated using phosphoric acid, H₃PO₄ and its ability to remove Safranin O from aqueous solution was investigated. The characterization of Senna fistula activated carbon was done by Scanning Electron Microscopy and Fourier Transform Infrared Spectroscopy. The impacts of pH, initial dye concentration, contact time, and effect of temperature were investigated. Results showed that the optimum pH for the removal of Safranin O was 4.4. The adsorption capacity increased as the initial dye concentration increased from 30 - 130 mg/L. The dye adsorption equilibrium data were properly fitted to both Freundlich and Langmuir isotherms. The maximum uptake capacity for Safranin O was 22.1 mg/g. The kinetic studies indicated rapid sorption dynamics via a second-order kinetic model. The thermodynamic parameter shows that the sorption of Safranin O on Senna fistula activated carbon was feasible, spontaneous and endothermic. Senna fistula-activated carbon was found to be cheap and efficient adsorbents for the removal of Safranin O dye from aqueous solutions.

Enoch Opeyemi O., Adeniji Adejimi A., Salaudeen Lukman O.,

Abstract

The analysis of the derivation of the Riemann Analytic Continuation Formula from Euler’s Quadratic Equation is presented in this paper. The connections between the roots of Euler’s quadratic equation and the Analytic Continuation Formula of the Riemann Zeta equation are also considered. The method of partial summation is applied twice on the resulting series, thus leading to the Riemann Analytic Continuation Formula. A polynomial approach is anticipated to prove the Riemann hypothesis; thus, a general equation for the zeros of the Analytic Continuation Formula of the Riemann Zeta equation based on a polynomial function is also obtained. An expression in Terms of Prime numbers and their products is considered and obtained. A quadratic function, G(tn), that is required for Euler’s quadratic equation (EQE) to give the Analytic Continuation Formula of the Riemann Zeta equation (ACF) is presented. This function thus allows a new way of defining the Analytic Continuation Formula of the Riemann Zeta equation (ACF) via this equivalent equation. By and large, the Riemann Zeta function is shown to be a type of L function whose solutions are connected to some algebraic functions. These algebraic functions are shown and presented to be connected to some polynomials. These Polynomials are also shown to be some of the algebraic functions’ solutions. Conclusively, &(z) is redefined as the product of a new function which is called H(tn; z) and this new function is shown to be dependent on the polynomial function, G(tn).

Enoch Opeyemi O., Alakofa Catherine O. , Salaudeen Lukman O.,

Abstract

In this study, a numerical integrator that is based on a nonlinear interpolant, for the local representation of the theoretical solution is presented. The resulting integrator aims to solve second and higher-order initial value problems as systems of first-order initial value problems. The method is designed to have two complex functions as control parameters. The control parameters may become real, depending on the nature of the second-order initial value problems to be solved. The generalization and properties of the scheme are also presented.

Sunday Joshua, N. Ndam Joel, J. Kwari Lydia,

Abstract

It is a known fact that in most cases, to integrate an oscillatory problem, higher order A-stable methods are often needed. This is because such problems are characterized by stiffness, chaos and damping, thus making them tedious to solve. However, in this research, an accuracy-preserving relatively lower order Block Hybrid Algorithm (BHA) is proposed for solution of second-order physical systems with oscillatory solutions. The sixth order algorithm was derived using interpolation and collocation of power series within a single step interval [tn; tn+1]. In order to circumvent the Dahlquist-barrier and also obtain an accuracy-preserving algorithm, four o-step points were incorporated within the single step interval. A number of special cases of oscillatory problems were solved using the proposed method and the results obtained clearly showed that it outperformed other existing methods we compared our results with even though the BHA is of lower order relative to such methods. Some of the second-order physical systems considered were the Kepler, Bessel and damped problems. Some important properties of the BHA were also analyzed and the results of the analysis showed that it is consistent, zero-stable and convergent 

Babalola M. I., Iyorzor B. E., Ebuwa S. O.,

Abstract

The structural, electrical, magnetic, mechanical, and thermodynamic properties of some novel half-Heusler alloys QCrAs(Q=Hf, Ti and Zr) are investigated using first principles calculations. The results show that the three half Heusler alloys are half metals and they can find application in spintronics industries. They possess magnetic moment of 3\mu_B. The mechanical properties shows that they are mechanically stable. The B/G ratio of the three half-Heusler alloys show that they are ductile in nature and the Poisson’s ratio reveal that the plasticity of TiCrAs and ZrCrAs are higher than that of HfCrAs. The Debye temperature and average sound velocity of ZrCrAs is observed to be higher than the other two alloys. This implies that the thermal conductivity of ZrCrAs is the highest.

Abdurrahman Abdulwasiu, Waziri Saidu Muhammad , Ajayi Olusegun Ayoola , Dabai Fadimatu Nyako,

Abstract

Increasing energy demand necessitates the production of sustainable fuels, which can be in the form of bio-fuels. One of such bio-fuels is biodiesel, which is typically produced via transesterification. The development of homogeneous catalyst that is relatively easy to synthesize, cheap, reusable, and environmentally friendly, is a major issue in transesterification reaction. The use of Deep eutectic solvent (DES) as catalyst, is believed to be a significant step in the direction of attaining a sustainable bio-economy. In this study, deep eutectic solvent was synthesized from different mole ratios of K2CO3/glycerol. The synthesized DES was used as catalyst in the transesterification reaction to produce biodiesel from Jatropha curcas oil. Box-Behnken design (BBD) was used to determine the factors that significantly affect the biodiesel yield. Optimum fatty acid methyl ester (FAME) yield of 98.2845% was achieved at optimum conditions of 1:32.58 mole ratio of K2CO3/glycerol, 8.96% w/w concentration of DES, and 69.58 minutes. GC-MS analysis revealed that the produced biodiesel contained 98.87% ester content. The properties of the biodiesel produced were characterized and found to agree with those of ASTM D6751-12 standard. Thus, suggesting the synthesized DES is a promising catalyst in the transesterification reaction to produce biodiesel from Jatropha curcas oil.

Ramanuja M., Kavitha J., Sudhakar A., Radhika N.,

Abstract

In this analysis, a computational study is conducted to examine the two-dimensional flow of an incompressible MHD SWCNT-blood nanofluid, saturated mass and porous medium .In addition to viscous dissipation, thermal radiation is taken into consideration. We developed the mathematical model and useful boundary intensity approximations to diminish the structure of partial differential equations based on the fluid for blood-based SWCNT underflow assumptions. Converted the partial differential equations by applying corresponding transformations to arrive at ODE’s. The above results are solved numerically by the Runge-Kutta 4th order technique. Noticed that there is desirable conformity when interpolated with the numerical one. The effects exhibited the velocity of SWCNT-blood nanofluid enhanced for defined standards of the viscosity parameter. Rise in temperature when various parameters like Prandtl number, Eckert number, and slip parameter are applied on SWCNT-blood. The impact of fluid flow on blood-based SWCNT is discussed graphically, and our results are tabulated along with illustrations. The design concepts, such as the Nusselt quantity and the local skin friction, conform to the analytical approach. Velocity reductions with an increase in CNT’s volume fraction, whereas enhancement in the blood temperature, is noted, which is directed to the rise in the heat mass transfer rates.

Lawal Y. B., Omotoso E. T.,

Abstract

The quality of services provided via Inter-Terrestrial radio communication links such as GSM networks, Wide Area Network (WAN), Radio and TV broadcasts is largely influenced by some meteorological parameters such as temperature, pressure and humidity. Proper knowledge of these parameters, specifically at microwave antenna heights (about 70m) is important in order to maintain an effective line-of-sight (LOS) link even during the worst weather conditions. The geoclimatic factor is an important quantity that must be considered in the design of terrestrial links for effective wireless communication. This work utilized satellite data from the European Center for Medium-Range Weather Forecasts (ECMWF) to compute the point refractivity gradient and geoclimatic factor for Yenagoa and its environs. The research was necessitated by the paucity of research on this subject matter for Yenegoa. The results of the research show that point refractivity gradient and geoclimatic factor in the study area vary with season. The average point refractivity gradient and geoclimatic factor at 70 m above the ground level are:136.433 N-unit/Km and 6.638633E-05 respectively. This implies that radiowaves propagating in this region at the said altitude is most likely to be super refractive in both rain and clear air atmospheric conditions. Rain or worst condition refers to the period when atmospheric components such as hydrometeor, lithometeor, aerosol have significant effects on propagated radio signals. Clear-air conditions means when maximum possible signal is received such that the most threatening atmospheric components (rain drops) have negligible effects on propagated signal. The results will be useful for radio engineers in the design and configuration of inter-terrestrial microwave links in Yenagoa and Its environs for optimum quality of service.

Itas Y. S. , Aminu Yamusa Shehu, Isah Ibrahim, Shaari A, Bello Ibrahim Usama, I. Kunya Salisu , Abdulkarim Sani, Alsalamh M.,

Abstract

In this research, the effects of Van der Waals forces on the structural, elastic, electronic, and optical properties of bulk transition metals dichalcogenides (TMDs) were studied using a novel exchange-correlation functional, vdW-DF3. This new functional tries to correct the hidden Van der Waals problems which are not reported by the previous exchange functionals. Molybdenum dichalcogenide, MoX 2 (X = S, Se, Te) was chosen as a representative transition metal dichalcogenide to compare the performance of the newly designed functional with the other two popular exchange-correlation functional; PBE and rVV10. From the results so far obtained, the analysis of the structural properties generally revealed better performance by vdW-DF3 via the provision of information on lattice parameters very closer to the experimental value. For example, the lattice constant obtained by vdW-DF3 was 3.161 Å which is very close to 3.163 Å and 3.160 Å experimental and theoretical values respectively. Calculations of the electronic properties revealed good performance by vdW-DF3 functional. Furthermore, new electronic features were revealed for MoX₂ (X = S, Se, Te). In terms of optical properties, PBE functional demonstrates lower absorption than vdW-DF3, as such it can be reported that vdW-DF3 improves photon absorption by TMDs. However, our results also revealed that vdW-DF3 performed well for MoS₂ than for MoSe₂ and MoTe₂ because of the lower density observed for the S atom in MoS2.

Al-Ali Suha Ibrahim Salih, Abudi Zaidun Naji, Abbas Mohammed Nsaif,

Abstract

The possibility of recovering one of the famous heavy metal ions, divalent copper, from contaminated aqueous solutions (which simulates wastewater) was studied in this study. The removal method was adsorption technique using a laboratory batch-mode unit, while the used tea leaves were the adsorption media. The adsorption process was performed under various operating conditions and  ranges that simulate the natural environmental conditions to determine the ideal values that achieve the maximum removal of copper ions. The acquired results demonstrated that the maximum remediation efficiency was 85%, which was achieved at treatment time, shaking speed, initial concentration, temperature, acid function, and adsorption dose of  90 min, 250 rpm, 70 ppm, 25°C, 4, 4.5 g, respectively. The values of the thermodynamic properties demonstrated that adsorption is spontaneous, exothermic and has negative entropy, while adsorption follows Langmuir’s model and the second pseudo-model according to the isotherm and kinetic studies, respectively. To conduct the Zero Residues Level concept, the loaded used tea leaves were prepared to study it effect as a simple type of rodenticide by applying it to Sprague Dawley rats. The results of the test show that the effectiveness of utilizing the residues as rodenticide and the LD50 of the proposed rodenticide were identical to those mentioned in the literature. Based on these results, the current study sheds light on the possibility of converting used tea leaves from harmful solid waste to an environmentally friendly substance using it as an effective adsorbent medium for the treatment of water polluted with heavy metals.

Duru Chidi, Enyoh Christian, Duru Ijeoma Akunna, Enedoh Margaret Chinyelu,

Abstract

The versatility of Polyethylene terephthalate (PET) as a material with numerous applications in the food industry and its recalcitrance to chemical and microbial degradation has recently made it an environmental nuisance. In this study, we applied computational methods to ascertain the dependence of PET nanoplastic (NP) degradation on the chain length of the oligomer. The binding affinities of the NPs on the novel enzyme Polyester Hydrolase Leipzig 7 (PHL7) were used to relate their ease of degradation at the enzyme active site. The results revealed that the binding affinity of PET NPs at the enzyme target decreased from -5.2 kcal/mol to -0.8 kcal/mol, with an increase in PET chain length from 2.18 nm to 5.45 nm (2-5 PET chains). The binding affinities became positive at chain lengths 6.54 nm (6 PET chains) and above. These findings indicated that PET NP degradation at this enzyme’s active site is most efficient as chain length decreases from 5-2 units and is not likely to occur at longer PET chains. A feedforward Artificial Neutral Network (ANN) analysis predicted that the energy of the PET NPs is a very important factor in its degradation.

Adejumo T. J., Akomolafe A. A., Okegbade A. I., Gbolagade S. D.,

Abstract

Mixture distribution refers to the combination of more than one probability distribution. Meanwhile, non-normality of data set may be inevitable and the cause may be as a result of mixed distributions thereby renders parametric tests ineffective. Montecarlo experiment was performed 5000 times under twelve sample sizes where data were generated from Gaussian and Cauchy distributions using R-statistical packages. At three commonly used alpha levels (0.1, 0.05 and 0.01), the robustness of the test statistics (Rank transformation t-test, Wilcoxon sign test (Distribution and Asymptotic), Signed rank test (Distribution and Asymptotic) and Trimmed t-test) were examined. When the type I error rate of a statistic approximately equal to the true error rate then the statistic is considered robust. At 0.1 and 0.05, Rank transformation t-test, Wilcoxon sign test (distribution) and Trimmed t-test in this order are robust. Meanwhile, at 0.01 Rank transformation andWilcoxon sign test (distribution) were identified to be robust. Also, further counts at all levels of significance revealed that the Rank transformation test is robust and thereby recommended when data comes from a mixed distribution. Hence, this study has been able to identify test statistics that are robust when data comes from a mixed distribution in one sample problem.

Abubakar Abubakar Aminu, Sidi Mohammed, Ya'u Anas, Mansur Umar, Hassan Aliyu Abdullahi, Tijjani Usman,

Abstract

Over time x-ray department gains more patient throughput compared to when it was established, this may lead to changes in room usage, workload and occupancy factor. Therefore, it becomes imperative to re-evaluate the shielding adequacy of the facilities to ensure the appropriate shielding design goal is accomplished. The study was aimed at assessing the shielding adequacy of conventional x-ray rooms in ten radio diagnostic centres in Kano Metropolis using RADSHIELD software. This was a prospective, cross-sectional study. RadShield software version 1.1 was used in the study, parameters such as distances of each wall from a radiation source (D), the average number of patients per week (N), occupancy factor (T), and use factor (U) were inserted into the software together with the shielding design goal (P). Once the result was generated, the design and shielding variables were saved in .xml format. The data were analyzed using Excel 2016. Ten facilities were studied involving 14 x-ray rooms. Room III had the largest room size of 49.2 m2 while room X had the least room size of 12.8 m2. Room II had the longest source image distance (SOD) of 180cm while room IV had the shortest (120cm). The design barrier thickness was thickest (47 cm) in room II and thinnest (1.5 cm) in barrier 5 of room III. All the x-ray rooms had the ideal room size except facilities G and H. The design barrier thickness in the radiology department of all the conventional x-ray rooms involved in the study was adequate.

Otuokere Ifeanyi Edozie, Akoh Onyinye Uloma, Nwadire Felix Chigozie, Egbucha Joy Nwachukwu , Nwankwo Chinedum Ifeanyi, Wisdom Chiemela, Okwudiri Ogbonna Augustine ,

Abstract

The COVID-19 pandemic, caused by the SARS-CoV-2, has prompted international concern. The aim of this study is to identify SARS-CoV-2 nonstructural protein inhibitors-potentially bioactive phytocompounds from the traditional plant Psidium guajava. GC-MS analysis of P. guajava methanol leaves was investigated. In silico molecular docking, drug-likeness, toxicity, and prediction of the compounds’ substance activity spectra (PASS) were evaluated. GC-MS analysis identified thirty (30) phytocompounds. According to molecular docking, all the phytocompounds have strong binding energies. The phytocompound beta bisabolene gave the best binding affinity of -5.0 kcal/mole. The detected compounds were all in accordance with Lipinski’s Rule of Five (RO5). This showed that the identified P. guajava compounds would have lower attrition rates during clinical trials and thus have a better chance of being marketed. According to this research, a potential COVID-19 drug could be created using the newly identified
phytocompounds of P. guajava.

Bunonyo K. W., Amos E.,

Abstract

An inflammatory disease resulting in the pathological constriction of the intima and media of the arterial system, such as the aorta, causes symptoms like stroke, heart attack, or angina; This research investigates the convective flow of blood through a constricted cylinder and the effect of cholesterol growth rate on the motion in the presence of a magnetic field by transforming the problem into a system of time-dependent partial differential equations. The governing partial differential equations (PDEs) were transformed into dimensionless ordinary differential equations (ODEs) and solved using the Laplace method. After obtaining the analytical solution, Wolfram Mathematica was used to perform the numerical computation where the various physical parameters such as Soret number, radiation number, solutal Grashof number, Schmidt number, and Prandtl number were varied to their impact studied. The study discovered that increasing the Soret number causes an increase in blood velocity, whereas decreasing the Solutal Grashof number decreases blood velocity. Furthermore, an increase in radiation parameter increases the blood velocity, but a Soret number increase results in a decrease in the concentration of cholesterol in the fluid, a Schmidt number, and oscillatory frequency increase, causing the temperature to decrease. This research is useful for clinicians and mathematical modellers who are trying to understand the flow of cholesterol saturated fluid in the human vascular system and how best to proffer analytical and numerical solutions in synergy with laboratory investigation.

Owolabi Abiola Timothy, Idowu Janet Iyabo, Oladapo Olasunkanmi James, Ayinde Kayode,

Abstract

The most popularly used estimator to estimate the regression parameters in the linear regression model is the ordinary least-squares (OLS). The existence of multicollinearity in the model renders OLS inefficient. To overcome the multicollinearity problem, a new two-parameter estimator, a biased two-parameter (BTP), is proposed as an alternative to the OLS. Theoretical comparisons and simulation studies were carried out. The theoretical comparison and simulation studies show that the proposed estimator dominated some existing estimators using the mean square error (MSE) criterion. Furthermore, the real-life data bolster both the hypothetical and simulation results. The proposed estimator is preferred to OLS and other existing estimators when multicollinearity is present in the model.

Ajileye G., Aminu F. A.,

Abstract

This paper consider collocation approach for the numerical solution of Volterra-Fredholm Integro-differential equation using collocation method. We transformed the problem into a system of linear algebraic equations and matrix inversion is adopted to solve the algebraic equations. We substituted the solution algebraic equations into the approximate equation to obtain the numerical result. Some numerical problems are solved to demonstrate the efficiency and consistency of the method.

Owolabi Abiola T., Ayinde Kayode, Alabi Olusegun O.,

Abstract

Despite its common usage in estimating the linear regression model parameters, the ordinary least squares estimator often suffers a breakdown when two or more predictor variables are strongly correlated. This study proposes an alternative estimator to the OLS and other existing ridge-type estimators to tackle the problem of correlated regressors (multicollinearity). The properties of the proposed estimator were derived, and six forms of biasing parameter k (generalized, median, mid-range, arithmetic, harmonic and geometric means) were used in the proposed estimator to compare its performance with five other existing estimators through a simulation study. The proposed estimator dominated existing estimators when the mid-range, arithmetic mean, and median versions of k were used. However, the proposed estimator did not perform well when the generalized, harmonic, and geometric
mean versions were used.