Open Access Original Research Article

A New Accurate Formula for the Large-angle Period of a Simple Pendulum

Mohammed Bechiri

Asian Journal of Physical and Chemical Sciences, Page 1-10
DOI: 10.9734/ajopacs/2022/v10i130146

This paper presents a numerical solution of the nonlinear differential equation governing the non-sinusoidal oscillatory motion for the large angle period of a simple pendulum. The numerical method is based on the discretization of motion equation according to an explicit finite difference scheme. Also, an approximation formula giving the period on the large oscillations amplitude is developed and compared with the numerical model. The results showed a good agreement with a deviation less than 0.063%. The simple pendulum consists of a point mass attached to a massless and inextensible wire that is fixed at the upper end. The oscillations period value is calculated with a precision order of the one-tenth of the millisecond. The approximation formula developed in this work is simple, flexible and more accurate than other formula available in literature.

Open Access Original Research Article

Optimization of Acid Activated Ngbo Clay Catalysts in Esterification Reaction Using Response Surface Methodology

Veronica Nnenna Nwobasi, Philomena K. Igbokwe, Chijioke Elijah Onu

Asian Journal of Physical and Chemical Sciences, Page 11-27
DOI: 10.9734/ajopacs/2022/v10i130147

In this study, Box-Behnken”s Response Surface Methodology (RSM) was applied to study the esterification reaction effectiveness of acid activated Ngbo clay catalyst. The esterification were monitored based on the process conditions of temperature, duration, amount of reactant, catalyst weight and particle size. The Box--Behnken’s Response Surface Methodology indicates that the acid clay-catalysed esterification reactions proceed through dual mechanisms of Acid-complex and Alcohol-complex mechanisms with the Alcohol mechanism dominating. The esterification efficiencies of acetic acid and ethanol by acid activated Ngbo clay catalyst optimized using RSM models indicated the estimated esterification percentage of ˃99%. The predicted and experimental values under the same conditions showed less than 5% difference thereby making the Box-Behnken design approach an efficient, effective and reliable method for the esterification of acetic acid with ethanol. The produced catalyst was optimized using A-One way ANOVA modelling, which indicated correlation coefficient of the regression of 0.9940, which implies that 99.40% of the total variation in the esterification reaction was attributed to the experimental variables. The result obtained indicated that the process could be applied in the esterification of acetic acid to avoid the drawbacks of corrosion, loss of catalyst and environmental problems.

Open Access Original Research Article

Analysis of Movements in Spinal Cord Hemisection Treatment with Amniotic Membrane – Preclinical Study

M. F. Neves, J. L. R. Fonseca, P. C. S. Carvalho, A. P. C. Pereira, E. H. P. Polisel, S. M. P. Pröglhöf, L. B. Sant´Anna, M. O. Lima, E. A. L. Arisawa

Asian Journal of Physical and Chemical Sciences, Page 28-37
DOI: 10.9734/ajopacs/2022/v10i130148

Aims: This study aimed to evaluate the efficacy of Amniotic Membrane application in rats with Spinal Cord Injury induced by transverse hemisection using kinematic analysis and Sciatic Functional Index.

Study design: True experimental research design.

Place and Duration of Study: Instiuto de Pesquisa e Desenvolvimento (IP&D) of Universidade do Vale do Paraíba (UNIVAP), between September 2016 and December 2017.

Methodology: Fifteen adult male rats were used, allocated into three equal groups: Control (the spinal cord injury and Amniotic Membrane application were simulated), Lesion (spinal cord injury not treated), Amniotic membrane (spinal cord injury treated by amniotic membrane). All animals underwent surgical procedures. A transverse hemisection was performed in groups Lesion and Amniotic Membrene. A fragment of the biomaterial was applied in group AM covering the hemisection area.

Results: Sciatic Functional Index and motion analysis were performed by comparing images taken at pre- and postoperative time at 7, 14, 21, and 28 days. The kinematic analysis showed a significant difference between groups Control and Lesion at 7 days (p = 0.023) and 14 days (p = 0.015), and between groups Lesion and Amniotic Membrane at 14 days (p = 0.039), comparing the postoperative periods. The Sciatic Functional Index revealed significant differences between Groups Control and Lesion at 7 (p = -0.002), 14 (p = 0.003), and 21 days (p = 0.009), between Groups Control and Amniotic Membrane at 7 (p = 0.014), 14 (p = 0.007), and 28 days (p = 0; 013), and between Groups Lesion and Amniotic Membrane only at 14 days (p = 0.039).

Conclusion: Application of amniotic membrane in spinal cord hemisection in rats induced gait recovery and improvement in SFI compared to the untreated group.

Open Access Original Research Article

Radiological Health Risk from Gamma Radiation of Coastal Communities in Okrika Local Government Area of Rivers State, Nigeria

Sokari S. A., Ononugbo C. P., Gbarato O. L.

Asian Journal of Physical and Chemical Sciences, Page 38-59
DOI: 10.9734/ajopacs/2022/v10i130149

In-situ measurement of background ionization radiation was carried out in coastal communities of Okrika Local Government Area. This field work was achieved with the use of Digilert 200 to record the background ionization radiation and global positioning system in taking the coordinates of the sampled Locations. The exposure rate ranged from 0.010  to 0.017 with a mean value of 0.0122+ 0.03, which is quite lower than the acceptable limit of 0.0133 . The absorbed dose varied from 85.70 nGy/h to 140.9 nGy/h with a mean value of 108.3+23.34 nGy/h. The mean value was a little higher than the world average of 89.0 nGy/h. The annual effective dose ranged from 0.13 mSv/y to 0.23 mSv/y with an overall mean of 0.1611+0.04 mSv/y. The overall mean value obtained was found to be lesser that the acceptable limit of 1.0 ms/y . The excess life cancer risk ranged from 0.47 x  to 0.79 x   with overall mean of 0.57+ 0.12 which is higher than the world average of 0.29 x . The study area is free from radiological hazards, even though there is no visible adverse effect on the populace, it is strongly recommended that companies and oil activities within the study area should be properly monitored to ensure that the populace and environment are free from radiological hazards, by ensuring that all forms of radiation exposure to both man and the environment should be kept as low as reasonably achievable.

Open Access Original Research Article

An Experimental Case Study on Generation of Bio-Energy as Clean Technology Initiative in a Food Industry

Rishiparna Guha, Susanta Podder, Tania Bhattacharjee, Sayantani Ghosh, Amitlal Bhattacharya

Asian Journal of Physical and Chemical Sciences, Page 60-66
DOI: 10.9734/ajopacs/2022/v10i130150

India is a country with huge potential for Biomass Energy (BE) generation numerically estimated as 20GW. The country is making some serious efforts in terms of both scientific interventions and fiscal incentives to economically attract more projects of BE for its renewability properties. Ministry of New and Renewable Energy (MNRE) Government of India is encouraging clean technologies (CT) to get adopted by revenue generating organizations through provisions of certificates for emission reduction, Carbon-Credits or giving preferential tariffs. These initiatives have been welcomed by industries as they often have large amount of bio-degradable waste to send to treatment facilities. Anaerobic Digestion (AD) process has got much attention in industrial waste treatment ventures in this framework. Bio-chemical breakdown process of waste releases biogas that can be utilized in electricity and steam generation and simultaneously landfill expenses can be avoided. Present study is based on an experiment of converting potato peels of a food industry to generate biogas. Standard AD process is utilized with a suitably selected pre-treatment mechanism to make the process of BE generation more efficient according to the scale of industrial dimensions. This venture is one of the many CT initiatives taken by the industry for achieving sustainability goals of the EHS (Environment-Health-Safety) division. The process is estimated to produce 16 lt methane gas per 1 kg of potato peel waste. This process of generation of BE is capable to off-set of 3000 Kcal amount of energy required for industrial operation. Further a SWOT analysis has been carried out to critically analyze the suitability of the experiment as per industrial scale.