Journal of Energy, Material, and Instrumentation Technology

Enhancement of Metal Electrode Corrosion Resistance through the Synergistic Effects of Three Organic Inhibitors: Jatropha Leaf, Tea Leaf, and Orange Peel Extracts

2026-07-09T04:33:52+00:00

Corrosion of metal electrodes is a major challenge in energy storage systems due to its impact on performance and service life. This study investigates the synergistic effect of Jatropha curcas leaf extract, Camellia sinensis leaf extract, and Citrus sinensis peel extract on the corrosion resistance of zinc (Zn) electrodes. The active compounds were characterized using UV–Vis and FTIR spectroscopy, while functional groups were identified through deconvolution analysis. Corrosion performance was evaluated using immersion tests and Linear Sweep Voltammetry (LSV). Results showed the presence of hydroxyl and phenolic groups capable of forming a protective layer on the Zn surface. LSV analysis confirmed that the combined extracts exhibited a synergistic effect, significantly reducing the corrosion rate compared to individual extracts. These findings indicate that natural extract combinations have potential as environmentally friendly corrosion inhibitors for zinc-based energy storage applications.

Influence of Cassava Starch Content on the Physical, Mechanical, and Structural Properties of Silica Aerogel-Containing Biofoam

2025-09-05T04:48:01+00:00

Cassava-starch-based biofoam is a promising biodegradable alternative to petroleum-based packaging materials. This study investigated the effect of cassava starch content on the physical, mechanical, and structural properties of biofoam containing corn cob fiber, polyvinyl alcohol (PVA), and silica aerogel. Four formulations were prepared by varying the cassava starch content from 48.75 to 56.25 g, while the amounts of corn cob fiber, PVA, and silica aerogel were kept constant. The samples were characterized in terms of density, water absorption, compressive strength, Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). The density remained approximately 0.6 g/cm³ for samples A–C and increased to 0.7 g/cm³ for sample D. Water absorption increased from 1.3% to 3.2% with increasing cassava starch content, indicating a higher hydrophilic character. Compressive strength varied considerably, with sample A showing the highest measured value of 6.09 MPa, whereas samples B–D exhibited values of 0.10–0.15 MPa. This substantial difference suggests that compressive strength was influenced by factors beyond starch content, including pore structure, fiber distribution, matrix formation, and sample homogeneity. The anomalously high value for sample A therefore requires verification through repeated testing. FTIR analysis confirmed functional groups associated with starch, PVA, corn cob fiber, and silica aerogel, while XRD indicated both crystalline and amorphous contributions. Overall, sample A exhibited the most favorable measured properties, although further verification is required before confirming it as the optimum formulation. The developed biofoam shows potential for biodegradable packaging applications, but further characterization is necessary to establish its suitability as a direct replacement for commercial styrofoam

Utilization of a Cyclone Turbine Ventilator as a Wind Turbine for Battery Charging Using a Spur Gear Transmission System

2024-01-08T03:49:39+00:00

This study investigated the use of a cyclone turbine ventilator-type wind turbine for battery charging through a spur gear transmission system. The study aimed to determine the relationship between wind speed and turbine speed, investigate the effect of the driven-gear tooth ratio on generator speed, and evaluate the efficiency of the wind turbine in converting wind energy into electrical energy. Three driven gears with 10, 15, and 20 teeth were used, while the drive gear had 80 teeth. The experiment was conducted at Tanjung Tua Beach, Bakauheni, South Lampung, on January 8, 2023, from 12:00 p.m. to 3:00 p.m. The battery voltage increased by a total of 5 V during the 3-hour charging period, during which the three gear ratios were used alternately. The highest turbine efficiency was 1.843%, obtained when the 10-tooth driven gear was used. The results indicate that the gear-tooth ratio affects the transmission of turbine speed to the generator and consequently influences the electrical output and charging performance. The cyclone turbine ventilator-type wind turbine with a spur gear transmission system therefore has potential as a small-scale renewable energy system for battery charging.

Physicochemical and Mechanical Characterization of Hydroxyapatite-Chitosan- PVA Composite Scaffolds Based on Marine Fish Bone Sources

2026-07-09T04:38:52+00:00

Design and Development of an IoT-Based Monitoring and Control System for Dual Lithium-Ion Battery Charging Using Photovoltaic Energy

2023-01-31T03:19:32+00:00

Despite the growing demand for eco-friendly electric vehicles powered by renewable solar energy, conventional battery management systems do not offer effective remote tracking nor do they efficiently handle charging path switching between dual batteries. To resolve this limitation, an Internet of Things (IoT)-based monitoring and control system was developed for dual Lithium-ion batteries (48 V 20 Ah) powered by a 100 Wp solar panel. The architecture utilizes a NodeMCU ESP32 microcontroller, a ThingSpeak platform, and a Twilio-based WhatsApp Bot for remote execution. Experimental evaluations spanning 390-minute daily cycles demonstrated that measurement errors did not exceed 3.35% (Voltage Sensor I and II achieved 97.53% and 96.65% accuracy, respectively). Furthermore, data transmission on ThingSpeak did not cause operational instability with an average latency of 10.3 seconds, while WhatsApp Bot commands took no longer than 3.72 seconds on average to activate relay responses (2.31–7.40 seconds). During charge–discharge cycles, Battery I gained +4.99 V during charging and lost -5.14 V during discharging, whereas Battery II lost -4.76 V during discharging and gained +5.40 V during charging. Overall, the designed prototype encountered no failures in tracking voltage dynamics or executing automated path switching, confirming its viability for smart renewable energy management.

Design and Experimental Evaluation of a 2.4 GHz Circular Microstrip Patch Rectenna with a Three-Stage Voltage Doubler for RF Energy Harvesting

2024-10-12T08:58:02+00:00

This study presents the design and experimental evaluation of a 2.4 GHz rectenna for radio-frequency (RF) energy harvesting. The system integrates a circular microstrip patch antenna fabricated on an FR-4 epoxy substrate with a three-stage voltage-doubler rectifier employing BAT17 Schottky diodes. Antenna parameters were optimized using ANSYS HFSS, and the selected configuration comprised an 18 mm patch radius, 24 mm feedline length, and 5 mm feedline width. The simulated antenna exhibited a VSWR of 12.7312 and a return loss of -4.0849 dB. The fabricated rectenna was experimentally tested using a Wi-Fi source during morning, afternoon, and evening periods. The maximum measured DC output voltages were 74.69, 56.77, and 80.78 mV, respectively, with the highest output obtained during the evening measurement. The results demonstrate the feasibility of harvesting RF energy from Wi-Fi signals using the proposed rectenna. However, the relatively high VSWR indicates that further impedance-matching optimization is required to improve RF power transfer and overall energy-harvesting performance.

Evaluation of Physicochemical Properties and Image Quality of Commercial Ultrasound Transmission Gels Across Three Price Ranges

2026-04-17T05:34:27+00:00

Ultrasound coupling agents, commonly known as ultrasound transmission gels (USTG), play a crucial role in ultrasound diagnostics, particularly for pregnancy check-ups and practice sessions for medical professionals or biomedical engineering students. In Indonesia, USTG is widely available on e-commerce platforms, with prices ranging from very low to high for the same packaging size. Previous study mainly focused on comparing commercial USTG to a cheaper material or alternative USTG using different material and methods. This study addresses this gap by systematically comparing USTG from low, medium, and high price categories. Through characterization techniques such as Fourier Transform Infrared (FTIR) spectroscopy, UV-Visible spectroscopy, Thermogravimetric Analysis (TGA), density testing, pH testing, and image quality assessment, it was found that the three selected gels (low, medium, and high price ranges) did not show significant differences in performance. Based on image analysis of gel A, B, and C significance value is 0.33 (p > 0.05) and this shows statistically not significant between each gel. This study provides valuable insights for individuals practicing ultrasound imaging techniques, helping them save costs without compromising quality.