Advanced Journal of Graduate Research 2023-01-20T14:26:18+00:00 Adv. J. Grad. Research Open Journal Systems <p align="justify"><a title="Click for Journal homepage" href="" target="_blank" rel="noopener"><img style="float: right; padding-left: 15px; padding-right: 5px;" src="" alt="AJGR" /></a>Advanced Journal of Graduate Research is a multidisciplinary, international journal featuring the work of graduate students and young researchers. This journal seeks to disseminate the work of emerging students who focus on scientific/technical content, regardless of their academic discipline. <em>Adv. J. Grad. Res.</em> publishes research carried out by graduate students and young researchers (Bachelor's degree students and Master's degree students) that sound scientifically and technically valid. This journal will serve as a global platform to broadcast new research initiatives being carried out by today's brightest youths as part of their graduate project.<br />Advanced Journal of Graduate Research is published by AIJR publisher (India) and registered with CrossRef with doi: 10.21467/ajgr and ISSN of this journal is 2456-7108 [online].</p> Evaluation of Power Performance of Solar Module Using Two Diode Model with MATLAB Simulation 2023-01-20T14:26:18+00:00 Md. Hafizur Rahman Shahena Akter Suman Chowdhury <p>This paper tries to represent the difference between single diode and two diode photovoltaic models in terms of efficiency simulated by MATLAB. The research activities done earlier had shown a clear preview that the solar cell can act as concentrated solar cell for increasing the conversion efficiency to a great extant so that output power can be improved to a large scale. Here for showing the manner of concentrated solar action double diode model has been calculated for observing the power difference in comparison with the solar cell of single diode as a convenient one. It has been observed that the photovoltaic module with two diode model is observed as highly efficient in comparison with single diode model. And this two diode model can be treated as highly efficient to convert the solar energy in the electric energy. Also, the behavior of power performance is observed practically which is included in this paper. And finally, a comparison has been drawn out to exhibit the verification of power performance for two diode model using MATLAB simulation. The mostly impact factors considered in this paper are solar irradiance and temperature affecting the power output from PV module.</p> 2023-01-20T00:00:00+00:00 Copyright (c) 2022 Md. Hafizur Rahman, Shahena Akter, Suman Chowdhury Preparation and Evaluation the Efficacy of Combined Mixture of Finger Root and Robusta Coffee Extracts on Antioxidative Activity 2022-12-02T05:29:28+00:00 Chotirod Kitsomchip Ratana Indranupakorn <p>Finger Root (FR) and Robusta Coffee (RC) are natural substances known to be beneficial for human health and used as a traditional medicine in various parts of the world. The efficacy of two commonly used extraction techniques [Ultrasound-Assisted Extraction (UAE) and maceration with stirring (MR)] and four different extraction solvents (50% ethanol, 80% ethanol, 100% ethanol and acetone) on antioxidant activity and the Total Phenolic Content (TPC) in both herbs were investigated. The antioxidant potentials of the samples were determined by reducing capacity with Folin-Ciocalteu reagent, while the radical scavenging activity using 1,1-Diphenyl2-Picryl Hydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzothia zoline-6-sulfonic acid) (ABTS) assays. FR and RC extracts from UAE and using 80% and 50% ethanol as an extraction solvent, respectively, showed the highest antioxidant capacity compared to the other extraction processes. The combined mixtures of FR and RC (CFR) in the weight ratios of 1:1 was prepared and evaluated the antioxidant activity. The CFR extract showed a significant increase of TPC and resulted in its strong radical scavenging activity, quite the same level in comparison to the model antioxidant substance, ascorbic acid, compared to when they were assayed independently. Stability results indicated that the TPC of CFR extract was slightly decreased, by around 8.7% and the IC<sub>50</sub> values of CFR extract showed slightly increased from 7.13 to 9.06 µg/mL in DPPH assay and from 725.72 to 858.65 µg/mL ABTS assay after storage at room temperature over 1 month. Findings suggested that the extraction methods and different solvent polarity significantly affect polyphenol recovery. The combined mixture of FR and RC extracts, which is quite stable and enhances radical scavenging activity, is interesting to increase economic value and utilization in cosmetic industry.</p> 2022-12-01T00:00:00+00:00 Copyright (c) 2022 Chotirod Kitsomchip, Ratana Indranupakorn