Komunikasi Fisika Indonesia

Journal Information
ISSN / EISSN: 14122960 / 2579521X
Total articles ≅ 143

Latest articles in this journal

Riduan Alvinsen Sirait, Salomo Salomo, Juandi Muhammad, Erman Taer
Komunikasi Fisika Indonesia, Volume 19, pp 91-98; https://doi.org/10.31258/jkfi.19.2.91-98

This Research has carried out on natural sand originating from the Rokan river, Riau Province by converting it into magnetic iron oxide nanoparticles to determine changes in magnetic properties and particle size. Natural sand samples of the Rokan river were separated between magnetic and non-magnetic particles using an iron sand separator (ISS). ISS products are further synthesized using ball milling and coprecipitation methods. 70-hour ball milling products, coprecipitation without ball milling and coprecipitation with 70-hour ball milling are then given NdFeB (neodymium iron boron) magnets to clean impurities containing non-magnetic elements. The results of this study showed that the highest magnetic acceptability value was obtained in coprecipitation products with ball milling, which was 12.9 × 10-2. This is because coprecipitation products have an abundant content of chemicals in the form of magnetic elements. Based on the results of chemical composition testing using X-ray flourescence (XRF) it was found that in coprecipitation products with ball milling there was 64.504% iron (Fe) content, while 70-hour ball milling products and coprecipitation without ball milling the percentage of Fe protection was 15.023% and 54.152%, respectively. Based on the results of the identification of the chemical composition in the sample, coprecipitation products with 70-hour ball milling have high magnetic induction values and magnetic suseptibility caused by the magnetic content in products such as Fe which are very high and non-magnetic content is very low such as Si compared to 70-hour ball milling products and coprecipitation products without ball milling.
Rahman Kurniawan, Salomo Salomo, Erwin Erwin, Defrianto Defrianto
Komunikasi Fisika Indonesia, Volume 19, pp 113-118; https://doi.org/10.31258/jkfi.19.2.113-118

The composition, crystallinity and magnetic susceptibility of nanoparticles in natural sand of the Rokan River, Riau Province have been investigated. After the iron sand separator (ISS) process, the natural sand samples were separated using NdFeB magnets to separate iron oxide particles and other non-ferrous oxides. For 70 hours, the NdFeB product was prepared using the ball milling method to produce BM products. The BM products were ball milled for 30 hours with a manganese doping concentration of 0 wt.%; 5 wt.%, and 10 wt.% produced DM 0, DM 5 and DM 10 products. Magnetic susceptibility values increased based on the values of B0 and BT measured using Pasco Magnetic Probe PS-2162. The results of XRD analysis of DM products contain a hematite phase (α-Fe2O3) which has a hexagonal structure. The crystal size increased along with the increasing concentration of Manganese from 25.494 nm; 25,542 nm to 25.669 nm. The results of XRF analysis of DM products on Fe elements decreased in percentage with increasing Manganese concentration from 18.083%; 15.407% to 12.947%. Other chemical elements such as Si, Al, K, P, Ti, Ca, Ti, Cr, Zn, V and Pbalso decreased.
Erman Taer, Juwita Ade Putri, Novi Yanti, Apriwandi Apriwandi, Rika Taslim
Komunikasi Fisika Indonesia, Volume 19, pp 119-127; https://doi.org/10.31258/jkfi.19.2.119-127

Red ginger leaf waste (Zingiber Officinale Var Rubrum) has been successfully processed as an active carbon base material for supercapacitor electrodes. The process of making carbon electrodes starts from the preparation of the original material, drying, refining, chemical activation, integrated pyrolysis and neutralization. The focus of this research is on the chemical activator ZnCl2 which is used with different concentrations of (0.1 and 0.5) M. Activated carbon powder is printed using a press to produce carbon in the form of solid coins of uniform size. The optimization of the carbon element in the sample is carried out through a pyrolysis process at high temperature with a one-stage integrated technique. Where, carbonization in the N2 gas environment is carried out starting from room temperature 30°C up to 600°C followed by physical activation until the high temperature reaches 800°C in CO2 gas environment. Characterization of activated carbon samples from red ginger leaves begins with determining the amount of shrinkage that occurs in the pyrolysis process by measuring the mass, diameter and thickness of the carbon coins. Furthermore, the electrochemical properties were tested using two methods, namely cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD) in a symmetrical two-electrode system. The electrochemical characterization was carried out under the influence of an aqueous electrolyte of 1M KOH and 1M Na2SO4 at a low potential window of 0-1 V. The optimum conditions of electrochemical properties were found in the red ginger leaf activated carbon sample with a ZnCl2 activator concentration of 0.5M for the electrolyte. KOH with a specific capacitance value of 115.9 F/g. while for electrolyte Na2SO4 found in ZnCl2 activator 0.1M with a value of 72 F/g. Through these results, red ginger leaves are known to have great potential as a base material for activated carbon electrodes to improve the performance of supercapacitors.
Martha Theresia Simanjuntak, Awitdrus Awitdrus
Komunikasi Fisika Indonesia, Volume 19, pp 65-68; https://doi.org/10.31258/jkfi.19.2.65-68

Supercapacitors areenergy storage devices consisting of electrodes, electrolytes, current collectors, and separators. Supercapacitor cells have components called electrodes. In this study, the basic material used to make supercapacitor cell electrodes is young coconut fiber with variations in physical activation temperature of 700°C, 750°C and 800°C. The process of preparing of supercapacitor cell electrodes begins with pre-carbonization using an electric oven, chemical activation using 0.5M KOH activator, carbonization process using N2 gas at a temperature of 600°C and physical activation using CO2 gas. Analysis of the  supercapacitor cell electrodes made from young coconut coir showed that the sample with a physical activation temperature of 750°C was the best sample, indicatedby a low density value of 0.68 g/cm3andthe highest specific capacitance of 225.1736 F/g which was tested using Cyclic Voltammetry method.
Yeni Pertiwi, Nur Hadziqoh, M Andriza Mustofa
Komunikasi Fisika Indonesia, Volume 19, pp 83-90; https://doi.org/10.31258/jkfi.19.2.83-90

Babies born prematurely always increase every year. For this reason, it is necessary to take proper care so that the baby remains in good health. One of the treatments for premature babies is phototherapy to reduce bilirubin levels in the baby's body. In order for the phototherapy process to run as expected, of course the phototherapy equipment used in the treatment must be of good quality and quality. For this reason, quality assurance and phototherapy equipment need to be carried out through a calibration process. In this study, calibration of the GEA medical type XHZ-90 phototherapy tool was carried out. Calibration is carried out by following the standard reference work method from the Ministry of Health in 2018. Calibration is carried out by checking the physical and function of the equipment which gains a weight of 10%, electrical safety inspection of the appliance with a weight gain of 36%, and measuring the performance of the instrument, namely spectral irradiance with a weight gain of 50%. . So that the total weight gain can be 96% and it can be concluded that this tool is functioning properly and within the tolerance limits of use. The uncertainty value in the measurement of spectral irradiance takes into account the sources of uncertainty types A and B. The combined uncertainty calculation from several sources for the measurement of spectral irradiance is 1.116. This value has met the uncertainty tolerance limit value of 4.
Eka Nurul Hidayah, Munasir Munasir
Komunikasi Fisika Indonesia, Volume 19, pp 99-107; https://doi.org/10.31258/jkfi.19.2.99-107

Natural zeolite is one of the alternative adsorbents with good absorption capabilities, including in absorbing color. The adsorption ability of zeolite can be increased by the activation process because it can increase the Si/Al ratio and pore size. Dragon fruit peel is a natural material that can be used as a natural dye because it contains betacyanin pigments which are equivalent to synthetic dyes. This study aimed to investigate the characteristics of activated green and brown zeolite and their adsorption ability on natural dyes of dragon fruit peel. Zeolite was activated chemically using 3M HCl solution and physically through a heating process of 500°C, then characterized using XRD and FTIR. The zeolite adsorption process was carried out with variations in contact time of 30, 60 and 90 minutes and variations in the mass of the adsorbent 0.1, 0.3 and 0.5 grams. The results of XRD analysis showed that the green and brown zeolite contained mordenite, nepheline and quartz minerals. The highest percentage of color degradation in the adsorption process was in brown zeolite at 27.70% at a contact time of 90 minutes and 88.2% at an adsorbent mass of 0.5 grams. Differences in brown zeolite before and after adsorption can be seen from the shift in the wavelength of each functional group due to the interaction with dragon fruit peel.
Minarni Shiddiq, Dian Eka Rachmawati
Komunikasi Fisika Indonesia, Volume 19, pp 57-64; https://doi.org/10.31258/jkfi.19.2.57-64

Electronic noses have been developed for decades in many fields. Recently, electronic nose has been used in agriculture to detect the ripeness of fruits because fruits also produce volatile gas during ripening. Oil palm fresh fruit bunches (FFB) is the main source of crude palm oil, its quality depends on the ripeness levels of oil palm FFB. Therefore, electronic detections of oil palm FFB ripeness need to be developed. This study was aimed to investigate the effect of temperature variation on the sensitivity of gas sensors in an electronic nose designed for detecting the ripeness of oil palm FFB. The electronic nose used in this study consisted of 4 sensors which were TGS 2611, TGS 2620, TGS 813 and TGS 822. Samples were peeled fruitlets of ripe oil palm FFB which were heated to temperatures of 30°C, 45°C, and 60°C. Response of each sensor was represented as a trapezoid area of voltage versus time for convenience. The results showed that there was a significant difference in the output voltage of each sensor when the sample temperatures were varied. Fruitlets of oil palm FFB heated at 60°C resulted in higher trapezoid area which mean more volatile gas released.  Based on the resulted trapezoid area for each sensor. Sensors of TGS 2611 and TGS 822 are the most sensitive which have higher trapezoid area for the variation of the temperatures.
Herna Herna, Farhan Lutfi, Ebigail Nur Tabita Tambunan, Yessi Meinarti, Ari Sulistyo Rini
Komunikasi Fisika Indonesia, Volume 19, pp 75-82; https://doi.org/10.31258/jkfi.19.2.75-82

The latest generation of photovoltaic cells are perovskite-based solar cells that can be fabricated through a simple and affordable process using high-efficiency solar power. This review also present zinc oxide (ZnO) adopted as an electron transport material (ETM) layer in the planar perovskitesolar cells due to its simple shynthesis and excellent electrical properties. ZnO ETM in conventional perovskite. Doping Aluminium (Al) with ZnO (AZO) was used the organic cation (CH3NH+3) of perovskite. The AZO ETM  was prepared by spin coating technique with AZO sol-gel   0, 0.5, 1, 1.5, 2, 2.5 and 3% Al doping. The perovskite solar cells with AZO ETM above 1.5% Al doping exhibits better and stable the performance cells because doing so can encourage the charge transporting and match the band energy with MAPl3 compared to pure ZnO.
Suryadi Simbolon, Usman Malik
Komunikasi Fisika Indonesia, Volume 19, pp 108-112; https://doi.org/10.31258/jkfi.19.2.108-112

Groundwater, one part of water resources is the most needed by humans for life. The availability of ground water and the increasing population growth in Tangkerang Labuai Village reguire the use of clean water. This study aims to determine the rock layers that makes up the soil and soil aquifers and the quality of groundwater. For the soil layer, it user the Schlumberger configuration geoelectric method,for the aquifer test, uses the Jacobs step drawdown method to determine the decrease of groundwater level is time. For air quality uses radians where the pH, TDS, turbidity values describe the resistivity value. The results of the research based on data processing on a 90 m long track,ground water is found at a depth of 7-10 m with a resistivity value of 114 m, which is categorized as granite, sand, gravel, alluvium constituent layers with a resistivity value of < 1000 m or the aquifer is partially connected due to the presence of a porous rock layerhaving small pores. To test the aquifer in the well based on the relatively small decrease in groundwater, namely 0.2 and 0.1 cm with a discharge of 0.43 liter/second with a transmissivity value of 971.901 m2/day, categorized as free or connected aquifer. Groundwater could not be consumed from the results as as stated to the regulation of the Minister of Health of the Republic of Indonesia number 492 of 2010, because the pH obtained was < 6.5 or acidic nature and categorized as partially connected aquifers because the more acid of water is formal, the higher the resistivity value is obtained.
Melyna Handayani, Juandi Muhammad
Komunikasi Fisika Indonesia, Volume 19, pp 69-74; https://doi.org/10.31258/jkfi.19.2.69-74

Digital technology in the form of a drying oven is used for the drying process of a sample biomass fuel. There are 2 types of biomass used, namely Coconut Shell and Acacia tree branches. The biomass is used as fuel for the drying process in the drying oven. This study aims to analyze a change in temperature, humidity and heat with various mass variations in coconut shells and acacia tree branches. Mass variations used are 1000 gr, 1500 gr, 2000 gr, 2500 gr, and 3500 gr. The research process begins by burning biomass from the first mass variation to the last mass variation. Furthermore, in the process of burning biomass, the resulting data is accessed via the internet of things seen from a website. The results of the data have a time span of 5 minutes for each observation of temperature and humidity. The data results are the comparison of time with internal temperature on coconut shells with the highest temperature of 93.7°C with a long burning time of 440 minutes, while on wood twigs the highest temperature is 93.7°C and the time required for the combustion process is 445 minutes. The best heat produced in coconut shell of 3500 gr with a maximum heat of 377.43 Joules at an internal temperature of 61.8°C for 45 minutes. Acacia tree branches have the best calorific value with a mass of 1000 gr, it’s maximum heat of 288.82 Joules at 37.7°C for 10 minutes.
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