Journal of Technomaterial Physics

The Effect of Fe3O4 Addition on the Density and Porosity of Cellulose Nanofiber Aerogel Extracted by Oil Palm Trunk

Diana Alemin Barus, Anindya Chandra Faizah — Thu, 31 Aug 2023 00:00:00 +0700

This study investigates the influence of Fe₃O₄ addition on cellulose nanofiber aerogels' density and porosity characteristics. The cellulose nanofiber aerogels were synthesized with varying concentrations of Fe₃O₄: 0%, 0.25%, 0.5%, 0.75%, and 1%. The characterization of the cellulose nanofiber aerogels included physical tests to determine density and porosity and Fourier transform infrared (FTIR) analysis for functional group analysis. The results reveal a progressive increase in density from the lowest to the highest Fe₃O₄ concentrations: 0.115 g/cm³, 0.135 g/cm³, 0.162 g/cm³, 0.163 g/cm³, and 0.241 g/cm³ for Fe₃O₄ concentrations of 0%, 0.25%, 0.5%, 0.75%, and 1%, respectively. Similarly, the porosity of the cellulose nanofiber aerogels exhibited a trend of decreasing values from the lowest to the highest Fe₃O₄ concentrations: 90.808%, 89.499%, 88.064%, 87.764%, and 82.844% for Fe₃O₄ concentrations of 0%, 0.25%, 0.5%, 0.75%, and 1%, respectively. Furthermore, FTIR analysis indicated that the structural integrity of the cellulose aerogels remained unchanged even after the incorporation of Fe₃O₄. While no new functional groups emerged, a discernible shift in wave numbers suggests the formation of bonds between the polymer network and Fe₃O₄. In conclusion, adding Fe₃O₄ to cellulose nanofiber aerogels led to notable alterations in density and porosity, while FTIR analysis confirmed the establishment of bonds between the polymer network and Fe₃O₄ without causing significant structural changes.

Manufacture and Characterization of Adsorbers Utilizing Pahae Natural Zeolite-Chicken Eggshell for Purifying Used Cooking Oil

Susilawati Susilawati, Bella Alfira — Thu, 31 Aug 2023 00:00:00 +0700

This research investigates the synthesis and characterization of Pahae natural zeolite-chicken eggshell adsorber to refine used cooking oil. The primary objective is to develop effective adsorbents for enhancing the quality of used cooking oil through refining. The methodology involves sieving the zeolite through a 74 µm sieve, chemically activating it using a 10% KOH solution for 1 hour and drying it at 100°C. The eggshells are also sieved through a 74 µm sieve, followed by washing and drying at 105°C for 12 hours. Various combinations of natural zeolite and chicken eggshell compositions (100% : 0%, 0%: 100%, 95%: 5%, 90%: 10%, 85%: 15%, 80%: 20%) are then prepared and pressed using a hydraulic press under a load mass of 6 tons for 10 minutes. The resultant samples are further activated by heat treatment at 600°C for 2 hours. The adsorbents undergo a comprehensive characterization process, encompassing physical properties (porosity and water absorption), mechanical properties (hardness), surface morphology (SEM), elemental composition (XRF), X-ray diffraction (XRD) analysis, and practical applications assessment (density, viscosity, moisture content, color, and odor). The optimal adsorbent configuration is identified as 80% natural zeolite and 20% chicken eggshell composition, activated at 600°C, exhibiting a porosity of 81.54% and an oil absorption of 46.86%. The highest hardness value of 119.64 MPa is achieved with 100% natural zeolite composition at 600°C. SEM analysis indicates an average pore diameter of 1.232 µm, while XRF results highlight calcium (Ca) as the predominant element at 49.64%. XRD analysis confirms the formation of a rhombohedral crystal structure.

Manufacture of Polymer Concrete Based on Snake-Fruit Seeds (Salacca zalacca) and Sawdust with Polyester Resin as an Adhesive

Mahdi Jauhar Harahap, Zuriah Sitorus — Thu, 31 Aug 2023 00:00:00 +0700

This study aims to determine the effect of adding snake-fruit (Salacca zalacca) seeds and sawdust on polymer concrete's physical and mechanical properties. The results showed that the highest physical properties were 1.27 g/cm³ density, 12.5% porosity, and 13.22% water absorption. The lowest physical properties are a density of 0.85 g/cm³, porosity of 2.65%, and water absorption of 2.07%. The highest mechanical properties are compressive strength of 16.70 Mpa, tensile strength of 4.39 Mpa, and flexural strength of 7.93 Mpa. The lowest mechanical properties are compressive strength of 6.80 Mpa, tensile strength of 1.11 Mpa, and flexural strength of 1.50 Mpa. SEM test results showed that the microstructure of polymer concrete showed differences between concrete samples A1 (consisting of 35 g of snake-fruit seeds, 15 g of sawdust, and 15 g of polyester resin) and polymer concrete samples B1 (consisting of 30 g of snake-fruit seeds, 15 g of sawdust, and 20 g of polyester resin). The SEM analysis of the A1 concrete sample reveals a dark surface color and conspicuous white lumps, which are attributed to polyester resin and arise from inadequate mixing of ingredients. In the case of sample B1, a higher concentration of visible resin lumps is observed.

Enhancing Biodegradable Plastics' Physical Properties Through the Incorporation of Talas Beneng Starch (Xanthosoma undipes K. Koch) and Glycerol as a Plasticizer

Awan Maghfirah, Sudiati Sudiati, Silvia Ramadina, Dwi Ajeng Pratiwi — Thu, 31 Aug 2023 00:00:00 +0700

The manufacture of biodegradable plastics with the main ingredients of talas beneng (Xanthosoma Undipes K. Koch) starch, chitosan, and glycerol as a plasticizer has been carried out by various additions of starch and reduction of chitosan. Initial assessment of talas beneng starch reveals: starch content - 20.51%, water content - 8.58%, fat content - 12.71%, and protein content - 3.51%. Physical testing of biodegradable plastic produces thickness values ranging from 0.166 mm to 0.234 mm, tends to meet JIS Z-1707: 2019 standards, density value is 1.674 g/cm^3, and the lowest water absorption value is 20.51%, both meet SNI 7188: 2016 standards, and there is a decrease in mass every week for 28 days in the biodegradation test.

Synthesis and Electrochemical Characterization of Sodium-Ion Battery Anode Carbon Biomassa Based on Sunflower Seed Husk (Helianthus annuus)

Renaldo Simanjuntak, Dinda Amilia, Syahrul Humaidi, Achmad Subhan — Thu, 31 Aug 2023 00:00:00 +0700

This study aimed to synthesize materials from the carbon biomass of sunflower seed husk (Helianthus Annuus) for sodium ion battery anode. A simple carbonization process was carried out by roasting. The chemical activation process was conducted by adding KOH as much as 4M in 100 mL water solution for 20 hours. Then drying was done in the oven at a temperature of 100ºC for 20 hours, and then continued with the sintering process at a temperature of 900ºC for 2 hours. The sintered results were washed and hydrothermal for 20 hours at 200ºC with 4 mL H₂O₂ and 1 mL EG in 50 mL Teflon. The resulting acid degree was neutralized (pH ~ 7) with distilled water and then dried at 100ºC for 20 hours. The hydrothermal powder was pulverized using a mortar and pestle and then sieved on a 325 mesh sieve. Anode sheets were prepared by mixing active ingredients: PVDF: Super-P with a composition of 85: 10: 5 by adding 2 ml of DMAC solvent. Electrochemical characterization testing was carried out to see the resulting performance—the results obtained from EIS, CV, and CD show that commercial hard carbon is better.

The Effect of Using a Combination of Sorbitol and Glycerol Plasticizers on the Characterization of Edible Film from Porang (Amorphophallus oncophyllus) Starch

Awan Maghfirah, Sudiati Sudiati, Silvya Nurrein K. Br Sitepu, Meutia Widyanti — Thu, 31 Aug 2023 00:00:00 +0700

Edible films present an eco-friendly alternative for food packaging compared to traditional plastic materials. This study investigates the effects of glycerol and sorbitol plasticizers on the properties of edible films. The research involves crafting these films using porang (Amorphophallus Oncophyllus) starch. Glycerol plasticizers were incorporated at a concentration of 100%, while sorbitol was utilized at varying levels (0%, 25%, 50%, 75%, 100%) to evaluate their impact on film characteristics. The films were produced using the melt intercalation method at a gelatinization temperature of 80°C and a firing temperature of 70°C. Notably, the most favorable physical test outcomes were observed with adding 100% sorbitol, including thickness, density, water absorption, and degradability improvements. Meanwhile, adding 25% sorbitol yielded the highest tensile strength and elongation values.

Preparation and Characterization of Chitosan/Reduced Graphene Oxide Film as a Sensing Material

Thu, 31 Aug 2023 00:00:00 +0700

Sensing materials are crucial in a wide range of fields, including environmental monitoring, healthcare, security, and industrial applications. By leveraging their specific properties, sensing materials enable the development of innovative sensing devices and systems for improved detection, monitoring, and control of various parameters in our environment. This study aimed to prepare the chitosan/reduced graphene oxide film as sensing materials using a simple casting method. The reduced graphene oxide (rGO) was mixed with chitosan (CS), consisting of a concentration ratio of 200, 250, 300, 350, and 400 ppm. Three characterizations were used to describe the formed CS/rGO films, namely, Fourier transform infrared (FTIR), X-ray diffraction (XRD), and cyclic voltammetry (CV). FTIR and XRD analysis results were successfully performed, which showed that the process of loading of rGO and the film fabrication occurred in the physical interaction. The CV test also showed that the CS/rGO modified electrode has high sensitivity in PBH pH 7 and can be applied as a sensing material.

Determination of Air Stability Parameter Threshold Value for Cumulonimbus and Thunderstorm Cloud Events at Kualanamu Meteorological Station

Rajab Prima, Fendy Arifianto, Yosafat Donni H, Avrionesti Avrionesti — Thu, 31 Aug 2023 00:00:00 +0700

Many studies have carried out calculations related to atmospheric lability as a reference in weather forecasts, especially cumulonimbus clouds, and thunderstorms. However, many air lability index values are found to be inappropriate in each region because conditions in each region are different from each other in the region. So it is necessary to use precise index thresholds to determine weather conditions. In the study, observational data and data from Showalter Index (SI), Lifted Index (LI), K Index (KI), Severe Weather Threat Index (SWEAT), and Convective data were used. Available Potential Energy (CAPE) for ten years (2013-2022), then statistical calculations and verification for one year (2022) are carried out. The results obtained are the atmospheric stability index with the best accuracy in predicting the presence of cumulonimbus clouds and thunderstorms at the Kualanamu Meteorological Station, Deli Serdang is the best LI index to predict TS 00 and TS 12, and the best KI index to predict CB 00 and CB 12.

Improving Reading Accuracy of ACS712 Current Sensor with ATmega328 10-Bit ADC: Enhancing Resolution to 5Ma/BIT via AD620 Differential Amplifier and Kalman Filters

Josefan Osbert Pardede, Kurnia Brahmana — Thu, 31 Aug 2023 00:00:00 +0700

The study focuses on the development of a current measuring device that
incorporates the ACS712 current sensor, enhances the reading sensitivity of the
ACS712 current sensor from 27mA/bit to 5mA/bit through the implementation of
an AD620 differential amplifier, and employs a Kalman filter for improved
accuracy. This increase in current uses a differential amplifier AD620. An increase
in the sensitivity of the reading is carried out by utilizing the initial value of the
ACS712 sensor when it has not been connected to the circuit or an offset of 512 to
0 so that 10bit ADC data can be utilized to measure 4880 mV/A so that the
accuracy of reading 1-bit data is equal to 4, 8 mV/mA after being given a gain of
26.5 times. The signal enhanced from the AD620 will be filtered using the Kalman
filter program so that the signal generated after the increase will be stable, and the
current value that has been read will be displayed on the LCD screen. Based on the
analysis results, the ACS712 current sensor can effectively measure up to 5mA/bit
stably using the AD620 differential amplifier and Kalman filter.

Solar-Based Smartphone Charging Stations with Voltage, Current, and Power Monitoring

Thu, 31 Aug 2023 00:00:00 +0700

Renewable energy sources continue to be developed as alternative energy sources to reduce the use of fossil energy sources. One of them is a solar power plant that uses a light source from sunlight. For the public, electrical energy is useful to support work and communication activities such as using smartphones, but not many chargers are found in public places to charge smartphone batteries. It has designed and implemented a smartphone charging station to charge smartphone batteries using solar power. The smartphone battery charging on this smartphone charging station can display voltage, current, and power when charging the battery; this tool is equipped with an INA219 sensor, ATmega328 microcontroller, and solar power to make this tool look smart. The purpose of making this tool is to find out the working principle, voltage, current, and power and compare the charging time of the smartphone battery between the smartphone charging station and the manufacturer's charger. The working principle, when this tool charges the smartphone battery, the INA219 sensor receives output value data in the form of current and voltage. Furthermore, the sensor sends a signal to the ATmega328 to be converted and displayed as data on the LCD so that users can see the output value. The test results of the tool, when charging a smartphone battery using Micro USB, showed the average values of voltage, current, and power, respectively, of 11.7 volts, 0.48 amperes, and 5.98 watts. USB Type C shows the average voltage, current, and power values of 11.33 volts, 0.71 amperes, and 8.37 watts, respectively. The comparison of the duration of battery charging time on the manufacturer's Micro USB with the smartphone charging station has a difference of 27 minutes; the comparison of the duration of the smartphone battery charging time using the manufacturer's USB Type C with the smartphone charging station has a difference of 22 minutes.