Volume-9 , Issue-4 , Dec 2022, ISSN 2348-635X Go Back
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Open Access Article
N. Gandhi, Sree laxmi, D. Madhusudhan Reddy, Ch. Vijaya
Research Paper | Journal-Paper (WAJES)
Vol.9 , Issue.4 , pp.1-15, Dec-2022
Abstract
The current study describes a green method for synthesis of silica nanoparticles (SiNPs) from banana peels (Musa paradisiaca). Utilizing the Ultraviolet-Visible (UV-Vis) Spectrophotometer, Fourier Transform Infrared (FT-IR), Dynamic Light Scattering (DLS) and Zeta, X-ray Diffractometer (XRD), Scanning Electron Microscope (SEM), and Energy Dispersion Spectroscopy (EDS), these SiNPs were characterized and their effectiveness at inhibiting the growth of various microorganisms was when these SiNPs were synthesised, they displayed a colour change pattern, and a UV-Visible spectrophotometer analysis revealed a broad peak at 365 nm. The presence of Si content, as well as the appearance of phytochemicals such primary amines of proteins and significant amounts of fibre, were revealed by FT-IR analysis to be the essential factors in the capping and stabilisation of SiNPs. Nanoparticles had an average size of 45 nm and a zeta potential value of 21.3 mV, according to DLS and zeta potential measurements. An XRD analysis revealed a broad peak at 22o and 26o of 2? value, confirming the amorphous nature of the nanoparticles and their average size range of 35 nm. The particles were poly-dispersed, spherical in shape, and ranged in size from 7 to 60 nm with negligible agglomeration among the particles, according to higher magnification examinations with SEM analysis. A 45.22 weight percentage of silica was found in the sample by energy dispersive X-ray analysis, which points to the sample`s extreme purity. Gram positive and gram negative bacteria are used to test the produced nanoparticles for growth inhibitory action on various microorganisms, potentially showing inhibitory activity. The fruit peel of Musa paradisiaca was shown to be an effective and dependable green source for the manufacture of possible bio antibacterial SiNPs, according to the study`s findings. The current study also offers an accurate explanation of the physiochemical and biological approach of silica nanoparticles in plants, which promotes safer and more environmentally friendly agriculture and better plant growth.Key-Words / Index Term
Musa paradisiaca fruit peel (Banana), silica nanoparticles, microwave, FTIR, XRD, SEM, EDX, Uv-visible spectrophotometer, antimicrobial activity and physiological, biochemical analysis.References
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N. Gandhi, Sree laxmi, D. Madhusudhan Reddy, Ch. Vijaya, "Microwave Mediated Green Synthesis of Silica Nanoparticles, Characterization, Antimicrobial Activity, Promising Applications in Agriculture," World Academics Journal of Engineering Sciences, Vol.9, Issue.4, pp.1-15, 2022 -
Open Access Article
Performance Analysis of TCSC with Firing Angle Determination Based on Random Forest Algorithm
Niharika Agrawal, Faheem Ahmed Khan, Mamatha Gowda
Research Paper | Journal-Paper (WAJES)
Vol.9 , Issue.4 , pp.16-25, Dec-2022
Abstract
In order to meet the rising power demand, the options are to increase the generation and transmission facilities or to install more power plants. But installation of new power stations is costly matter and needs huge investment. So, it is desired to increase the power transfer capacity of the existing system. In the proposed work the use of fixed capacitors and Power -Electronics-based series FACTS device TCSC are done to increase the power transfer capacity of the system. The key contribution of this paper is the firing angle prediction by Random Forest Machine Learning Algorithm (RFMLA) for the various modes of TCSC. The trained data of input power and angle is loaded into the system and then firing angle prediction is done over the new data. Many decision trees are created for the input power and firing angle using MATLAB coding. The final value of firing angle is selected by the algorithm. The power flow and THD results are shown. FFT analysis tool in Powergui block is used to calculate THD voltage without compensation and then after using TCSC, combination of both FC and TCSC. The main issues and challenges in today’s smart power systems are meeting power demand and power quality problems like voltage sag and voltage swell created due to disturbances or faults, stability, contingency and congestion management with taking care of environment. The TCSC is capable of meeting all these challenges. The novelty here is the appropriate prediction of firing angle based on RFMLA.Key-Words / Index Term
Capacitor, Inductive ,Power quality, Total Harmonic Distortion, VoltageReferences
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Niharika Agrawal, Faheem Ahmed Khan, Mamatha Gowda, "Performance Analysis of TCSC with Firing Angle Determination Based on Random Forest Algorithm," World Academics Journal of Engineering Sciences, Vol.9, Issue.4, pp.16-25, 2022 -
Open Access Article
S.O. Okpo, I. Edeh
Research Paper | Journal-Paper (WAJES)
Vol.9 , Issue.4 , pp.26-33, Dec-2022
Abstract
Rubber seed husk is currently being discarded as agricultural waste, leading to economic loss. The current work assesses the possibility of converting this waste into activated carbon for potential use as an adsorbent. This was achieved using the physical method at 450oC for 1h and the chemical activation method through a one-step activation process with H3PO4 as the activating agent and an impregnation ratio of 1:1. The physicochemical properties of the formulated activated carbon were investigated, and functional groups were assessed using Fourier transform infrared spectroscopy (FTIR). The results of the physicochemical properties of the formulated activated carbon prepared using the physical method were: bulk density (0.4784 g/mL), pH (6.4), moisture content (0.730%), ash content (29.302%), volatile matter (21.66%), iodine number (16.624 mg/g), and surface area (525.4 m2/g). Results of the physicochemical properties of activated carbon prepared using chemical methods were: bulk density (0.4764 g/mL), pH (6.2), moisture content (0.2976%), ash content (29.302%), volatile matter (28.788%), iodine number (18.009 mg/g), and surface area (563.8m2/g). Regardless of method employed, FTIR investigations have revealed presence of alcohols, phenols, aldehydes, aromatics, amines, amides, carboxylic acids, esters, alkenes, and alkanes in manufactured activated carbon. The obtained result shows that high-quality activated carbon can be formulated from rubber seed husks using either physical or chemical methods.Key-Words / Index Term
Activated carbon; Adsorbent; Chemical activation; Physical activation; Pollution, Rubber seed husk; Wastewater.References
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S.O. Okpo, I. Edeh, "Formulation and Characterization of Activated Carbon from Rubber Seed Husk Using Physical and Chemical Methods," World Academics Journal of Engineering Sciences, Vol.9, Issue.4, pp.26-33, 2022 -
Open Access Article
Ship-Generated Marine Pollution and the Warri Port Environment
I. Njoku, E. M. Oluwaremi
Research Paper | Journal-Paper (WAJES)
Vol.9 , Issue.4 , pp.34-43, Dec-2022
Abstract
The study examines ship-generated marine pollution at Warri port with the intent of finding the cause and effect of such unwholesome practice. The primary and experimental data were employed for the study. The primary data were obtained through structured questionnaires administered to different categories of respondents including the crew, shippers, ship and port operators. Whereas the experimental data were generated from the wastewater collected from the port berthing areas where ships slated for cargo handling operations had anchored for more than 24 hours for one week. The research employed the use of descriptive statistics to analyse primary data while a physiochemical and microbiological analysis of samples of ships’ wastewater was conducted in Laboratory to determine the status of marine pollution in the Warri port environment. The Laboratory analysis comprises microbiological, chemical, and physical parameters of wastewater samples. The following parameters were tested: pH, total dissolved solids, total hetero-trophic bacteria, total hetero-trophic fungi, zinc, lead, iron, copper, total oil and grease, conductivity, etc. The result reveals that the port and its environs are polluted. It, therefore, suggests a synergy between regulatory agents and private cleaning companies for effective monitoring and controlling of pollution in seaports. The study also recommends that the government encourages public ownership and private sector operations of the port infrastructure in Nigeria.Key-Words / Index Term
marine pollution, ship-generated wastewater, physico-chemical and microbiological analysisReferences
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I. Njoku, E. M. Oluwaremi, "Ship-Generated Marine Pollution and the Warri Port Environment," World Academics Journal of Engineering Sciences, Vol.9, Issue.4, pp.34-43, 2022 -
Open Access Article
Y?ld?r?m Özüpak, Mehmet Ç?nar
Research Paper | Journal-Paper (WAJES)
Vol.9 , Issue.4 , pp.44-48, Dec-2022
Abstract
The increase in the use of portable electronic devices has increased the interest in studies on wireless charging applications technologies. The efficiency of this system is one of the most important parameters for the WPT system, which has become one of the popular research areas, especially in recent years, with technological developments. Many studies have been carried out using different techniques about the WPT system, which has advantages such as ease of use, no cable costs and freedom of movement. WPT systems, which are used in many application areas today, are considered to be the pioneers of the near future, especially for battery charging applications of electric vehicles. In this study, an application based on magnetic resonance coupling, which provides high efficiency wireless power transmission for electric vehicles, has been made. The analysis of the WPT transformer designed in the Finite Element Method (FEM) based ANSYS-Maxwell-3D environment has been made. The system parameters of the designed wireless power transmission system are obtained from an integrated platform ANSYS-Simplorer-Maxwell. It has been seen that the efficiency of the power obtained by integrated simulation studies is 88.6%.Key-Words / Index Term
WPT, Efficiency, Electric vehicles, FEM, ANSYS-Maxwell, TransformerReferences
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Y?ld?r?m Özüpak, Mehmet Ç?nar, "Analysis of Magnetic Resonance Coupled Wireless Power Transfer System Designed For Electric Vehicles With Finite Element Method Based ANSYS-Maxwell," World Academics Journal of Engineering Sciences, Vol.9, Issue.4, pp.44-48, 2022
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