The Jurnal Riset Fisika Indonesia (JRFI) (e-ISSN: 2797-6513; p-ISSN: 2776-1460) is an open access and peer-reviewed journal, published by Department of Physics - Universitas Bangka Belitung, which is a dissemination medium for research result from scientists, engineers, and practitioners in many fields of physics. JRFI is a biannual journal issued on December and June. The editors welcome submissions of papers describing recent theoretical and experimental research related to: (1) Theoretical articles; (2) Empirical studies; (3) Practice-oriented papers; (4) Case studies; (5) Review of papers, books, and resources. Focus and scope for JRFI as follows: Theoretical physics Computational physics Material physics Geophysics Instrumentation Applied physics
Jurusan Fisika, Universitas Bangka Belitung
Analisis Band Power, Relative Power, dan Entropi Sinyal EEG saat Relaksasi dengan Mata Tertutup berdasarkan Brain Region
Electroencephalography (EEG) is a widely used neurophysiological method for monitoring brain activity through scalp electrodes. This study investigates EEG signal characteristics in a resting state with eyes closed, focusing on three quantitative features: band power, relative power, and entropy. The experiment involved five healthy volunteers who were instructed to sit in a relaxed position with eyes closed for five minutes in a quiet, dimly lit room. EEG signals were recorded using an Emotiv EPOC+ device with 14 channels placed according to the international 10–20 system. The recorded signals were processed in MATLAB, including bandpass filtering (1–50 Hz), baseline correction, and artifact rejection. Subsequently, the signals were segmented into two-second epochs for feature extraction. Band power was calculated using the Fast Fourier Transform (FFT) for delta (0.5–4 Hz), theta (4–8 Hz), alpha (8–13 Hz), and beta (13–30 Hz) bands. Relative power was computed as the ratio of each band’s power to the total power of the signal, while signal entropy was estimated using Shannon entropy to assess complexity. EEG channels were grouped into four brain regions: frontal, temporal, parietal, and occipital. Results show that the occipital region exhibited the highest average band power, consistent with dominant alpha activity during eye closure. Relative power distributions were uniform across subjects and regions. The highest entropy values were observed in the temporal and frontal regions, indicating higher signal complexity in those areas. These findings highlight the effectiveness of combining spectral and nonlinear features to characterize brain activity during rest and provide valuable baselines for future applications in Brain-Computer Interfaces (BCI), stress detection, and neuropsychological mapping.
Copyright (c) 2025 Iqbal Robiyana, Nurizati, Tedi Sumardi, Aditia Ramadhan, Muhammad Agung Suhendra http://creativecommons.org/licenses/by-sa/4.0
Analisis Fraktal untuk Pengembangan Motif Batik Indonesia: Perpaduan Fisika dan Budaya
Batik as part of the Indonesian culture was recognized as an Intangible Cultural Heritage by UNESCO in 2009. Batik is not only a cultural product, but also a representation of a complex visual structure. As science and technology develop, a physico-mathematical approach to batik motifs, particularly through fractal theory, has begun to attract the attention of researchers. A fractal is a geometric shape that has a repeating pattern at various scales. This study aims to develop a fractal pattern using the Julia set to obtain a batik motif pattern. This will greatly assist the batik industry in producing batik with various motifs automatically. The method used is to modify the Julia equation, the next step is to perform a transformation in the form of rotation or dilation. Then the results obtained are visualized using Python programming. The constants used are varied with a value of -1 < c < 1, the order of the equation also uses a higher order. The visualization results are then compared with existing batik motifs and the best one is selected. The results showed that certain parameter modifications produced fractal patterns similar to traditional designs such as kawung batik, while others revealed unexpected analogies to natural and physical phenomena like dicotyledonous and monocotyledonous stems patterns and floral motifs.
Copyright (c) 2025 Siti Ayu Kumala, Didik Nur Huda, Retno Nengsih http://creativecommons.org/licenses/by-sa/4.0
Fabrikasi dan Analisis Material Komposit Anti Peluru Carbon Fiber-Epoxy Resin Berpenguat Nanokristal Selulosa Berbasis Limbah Kertas
Waste paper contains up to 64.84% cellulose, making it a potential raw material for the synthesis of nanocrystalline cellulose (NCC) via sulfuric acid (H₂SO₄) hydrolysis. The use of 1M H₂SO₄ produced NCC with favorable characteristics, including a cellulose purity of 80.79%, a crystallinity index of 88.73%, and a crystal size of 3.18 nm. Subsequently, bulletproof composites were fabricated using carbon fiber–epoxy resin reinforced with nanocrystalline cellulose. The independent variable in this study was the ratio between nanocrystalline cellulose powder and epoxy resin. The fabricated bulletproof composites measured 200 × 200 mm in area and had a thickness of 20 mm. The results showed that composites containing 0% and 10% NCC (designated as KAP-01 and KAP-02) were capable of withstanding the impact of 9×19 mm handgun bullets, meeting the requirements of NIJ Standard-0101.04 Level IIIA. However, the bulletproof composites in this study were not able to resist penetration from 5.56×45 mm rifle rounds.
Copyright (c) 2025 Firza Roehafi, Herman Aldila http://creativecommons.org/licenses/by-sa/4.0
Identifikasi Akuifer Air Tanah menggunakan Metode Geolistrik di Perumahan Gang Jati Baru, Hajimena, Natar, Lampung Selatan
Groundwater is a basic human need. However, the residents of Perumahan Gang Jati Baru, Hajimena, Natar face significant challenges in meeting their water demands, particularly during the dry season when water availability is critically reduced. To explore groundwater resources in Perumahan Gang Jatibaru, geoelectric measurements need to be conducted. The Schlumberger configuration is used for 1D measurements, while the Wenner-Schlumberger configuration is used for 2D data acquisition. The modeling results indicate the presence of shallow groundwater aquifers at depths ranging from 11.1 to 28.3 meters, and deeper aquifers at depths between 42.7 and 79 meters, characterized by low resistivity values of approximately 13.2 13.2 ohm.m. These findings are corroborated by the 2D resistivity modeling conducted at the study site, which reveals a shallow low-resistivity anomaly (<15.2 13.2 ohm.m) occurring at depths of 10 to 28 meters.
Copyright (c) 2025 Isti Nur Kumalasari, Rahmi RahmiMulyasari, Ordas Dewanto, Bagus Sapto Mulyatno, Rahmat Catur Wibowo, Nanda Hanyfa Maulida, Akroma Hidayatika, Hesti Hesti, Ilham Dani, Sandi Erfani http://creativecommons.org/licenses/by-sa/4.0
Analisa Kandungan Boraks pada Tahu dengan Menggunakan Texture Analyzer dan Spektrometer
Food safety is a critical issue in ensuring public health, especially in preventing contamination from harmful substances illegally added to food. One such hazardous additive is borax, which is sometimes used by unscrupulous food producers to preserve texture and shelf life, despite its known toxicity and prohibition in food products. This study aims to detect the presence of borax in tofu, a widely consumed protein source, by utilizing two analytical tools such as a Texture Analyzer and a Spectrometer. The Texture Analyzer was employed to evaluate the physical firmness of tofu, as borax is known to increase its hardness. The Spectrometer was used to confirm the chemical presence of borax. Results indicated that tofu samples containing borax showed significantly firmer textures compared to control samples, and the spectrometric analysis successfully detected borax compounds. These findings demonstrate that both instruments are effective in identifying borax contamination. The study recommends the sustainable development of rapid and accurate detection methods for other hazardous additives to enhance food safety monitoring and enforcement practices.
Copyright (c) 2025 Permono Adi Putro, Novita Dwi Susanti, Devia Putri Wulandari http://creativecommons.org/licenses/by-sa/4.0
Sistem Monitoring Kesuburan Lahan Pertanian menggunakan Sensor pH, Sensor Suhu, Intensitas Cahaya, dan Kelembapan Tanah Berbasis Internet of Things
This study developed an Internet of Things (IoT)-based soil fertility monitoring system to measure soil pH, soil moisture, and light intensity in real time, specifically for peatland agriculture. The system utilizes pH sensors, soil moisture sensors, and light intensity sensors calibrated with standard measuring instruments to ensure accuracy. Calibration results indicate that the pH sensor has an average error of 0.151%, the soil moisture sensor 1.11%, and the light intensity sensor 6.152%, with the latter exhibiting the highest variation due to environmental factors. Monitoring data shows that soil pH fluctuates more during the day (4.45–4.60) compared to a more stable range at night (4.75–4.80). Soil moisture remains high during the day at 85–90%, while at night, it gradually increases from 25% to 35%. Light intensity fluctuates between 9000–12000 lux during the day and approaches 0 lux at night. With high accuracy and real-time data accessibility, this system can assist farmers in optimizing irrigation, fertilization, and peatland soil management using IoT-based technology, ensuring sustainable agricultural productivity in peatland environments.
Copyright (c) 2025 Samsul Arifin, Neny Kurniawati, Reni Agustiani, Gabriela Elsandika http://creativecommons.org/licenses/by-sa/4.0
Pengaruh Penambahan Gliserol Terhadap Karakteristik Bioplastik Selulosa Batang Pisang/Kitosan
The usage of plastics has brought negative impacts to the environment. Therefore, the development of bioplastics is required to solve the impact of the usage of plastics on the environment. In this study, bioplastics were developed based on banana stem cellulose, chitosan, and glycerol. The objective of this study was to determine the content of banana stems cellulose, functional groups, and the effect of glycerol addition on the thickness, mechanical properties, and degradation rate of bioplastics. The research was started by extracting cellulose from the stem of banana. Bioplastic synthesis was performed by adjusting the addition of glycerol. The bioplastics were examined for thickness, mechanical properties, functional groups, morphology, and degradation. The results indicated that the extracted banana stems produced cellulose with a concentration of 93%. It was identified to have cellulose functional groups in the form of O-H, C-H, and C-O. However, the addition of glycerol to bioplastics increased the thickness, elongation, and degradation rate, but decreased the tensile strength. Bioplastics with the best characteristics were produced by applying 3 mL glycerol with a thickness of 0,578 mm, tensile strength of 0,149 MPa, elongation of 2,7%, and completely degraded for 10 days.
Copyright (c) 2025 Diani Lestari, Indah Puspita, Tri Kusmita http://creativecommons.org/licenses/by-sa/4.0
Simulasi Mikromagnetik untuk Menganalisis Dampak Bentuk Geometri terhadap Sifat Magnetik Material Permalloy
The development of ferromagnetic material technology is currently experiencing very rapid progress in various fields. One of the technological developments in the field of developing ferromagnetic materials based on thin layers of soft magnetic properties is used in the manufacture of recording heads, Magnetic Tunnel Junction (MTJ) contained in Magnetoresistive Random Access Memory (MRAM) and various sensors. One example of a ferromagnetic material with softmagnetic properties is permalloy. Permalloy has high permeability and a magnetic moment configuration that is easily controlled with small changes in the magnetic field. The advantage of permalloy is that apart from its high permeability, it also has low coercivity, resistance to oxidation, and significant anisotropic magnetoresistance. Therefore, in this research micromagnetic simulations have been carried out for thin layers using permalloy material. This research was carried out using the OOMMF (Object Oriented Micromagnetic Framework) software simulation to obtain the influence of the shape of the permalloy material on the magnitude of the magnetization value, coercivity value and anisotropy energy value produced due to the influence of an external magnetic field. The research results show that the shift in the magnetic wall domain in this study produces different magnetization values ​​in each form of permalloy material, the difference in shape also affects the field coercivity value and the anisotropy energy value. This can be seen when the external magnetic field applied is 5000 Oe, the magnetization value in form 1 is 0.99997, with a coercivity field of 680 Oe and an anisotropy energy value of 5.72 × 10-28, for form 2 it has a magnetization value of 0, 9806628, with a coercivity field of 1240 Oe and an anisotropy energy value of 3.55 × 10-25, and form 3 has a magnetization value of 0.942093 with a coercivity field of 960 Oe and an anisotropy energy value of 1.00 × 10-25. An increasing magnetization value indicates that the material is saturated, and the resulting anisotropy energy value becomes smaller.
Copyright (c) 2025 Fenni vavionita, Anisa Indriawati, Herman Aldila http://creativecommons.org/licenses/by-sa/4.0
Pengaruh Konsentrasi Kitosan terhadap Karakteristik Fisik dan Mekanik Bioplastik Selulosa Batang Pisang dengan Plasticizer Gliserol
The development of bioplastics has continued to grow as an alternative material based on renewable natural resources. Cellulose is a natural polymer that is widely used as a raw material for bioplastics; however, cellulose-based bioplastics generally show limited mechanical stability and rigidity. Therefore, the addition of chitosan and glycerol is required to improve their characteristics. This study aims to determine the cellulose content and functional groups of banana stem cellulose and to analyze the effect of chitosan concentration on the thickness, mechanical properties, and degradation rate of banana stem cellulose-based bioplastics using glycerol as a plasticizer. Bioplastics were synthesized by varying the chitosan concentration at 1%, 2%, 3%, and 4%. The results showed that the cellulose content of banana stems reached 93%, with the presence of –OH, –CH, and –CO functional groups. The variation in chitosan concentration affected the thickness, tensile strength, elongation at break, and degradation rate of the bioplastics. An increase in chitosan concentration resulted in a decrease in thickness and elongation, while tensile strength and degradation rate increased with higher chitosan content. These results indicate that chitosan concentration significantly influences the physical, mechanical, and degradation properties of banana stem cellulose-based bioplastics, demonstrating their potential as biodegradable materials.
Copyright (c) 2025 oktavia oktavia, Indah Puspita, Tri Kusmita, Rizka Utami http://creativecommons.org/licenses/by-sa/4.0
Scaffold Hidroksiapatit (HAp) dari Limbah Tulang Ikan Tenggiri (Scomberomorus commerson): Studi Variasi PVA Terhadap Ukuran Kristal dan Ukuran Pori
Defects in bone tissue represent a significant health concern and continue to pose challenges in clinical surgery. The fabrication of scaffolds from hydroxyapatite (HAp) can support bone regeneration. However, producing HAp scaffolds with ideal pore structures for effective bone tissue engineering remains difficult. In recent decades, many studies have attempted to enhance HAp scaffolds by incorporating polymeric materials to address their limitations. In this study, corn starch was used as a pore-forming agent, and polyvinyl alcohol (PVA) served as a binder and pore size regulator. The scaffolds were fabricated using the freeze-drying method, which offers the advantage of forming porous structures while maintaining scaffold integrity. This study investigated the effects of varying PVA additions which 3 wt%, 7 wt%, and 10 wt%. XRD analysis showed that the diffraction peaks of all samples corresponded to the HAp phase, displayed β-TCP peaks, and a crystal size with values ranging from 0.96 nm to 11.77 nm. SEM analysis showed that the HAp-7 scaffold has the largest pore size distribution range of about 1.19 µm to 11.77 µm.
Copyright (c) 2025 Meisa Rohania, Frastica Deswardani, Yoza Fendriani, Ria Anjelina, Rista Mutia Anggraini, Lucky Zaehir Maulana, Febri Berthalita Pujaningsih http://creativecommons.org/licenses/by-sa/4.0
Identifikasi Ketebalan Lapisan Lapuk Pada Zona Rawan Longsor Menggunakan Metode Geolistrik Tahanan Jenis (Studi Kasus: Ruas Jalan Kolaka-Kolaka Timur)
The Kolaka-Kolaka Timur road section serves as a vital connection among several districts in Southeast Sulawesi. This region is particularly susceptible to landslides during the rainy season, resulting in the road being obstructed by landslide debris. The objective of this research is to assess the thickness of the weathered layer, a critical factor contributing to landslides, as part of efforts aimed at mitigating such events. The research employs the resistivity geoelectric method utilizing a Wenner configuration with five passes. The electrode spacing is set at 7 meters, covering a total track length of 105 meters. Analysis of the measurement results indicates that the weathered layer across each track comprises alluvial deposits originating from the weathering of Sekis rocks, characterized by a resistivity of less than 20 Ωm. The thickness of the weathered layer varies across the tracks: Track 1 exhibits a thickness ranging from 4 to 12 meters, Track 2 ranges from 1 to 10 meters, Track 4 varies from 0 to 8 meters, and Track 5 shows a thickness between 0 and 10 meters.
Copyright (c) 2025 triani triani, Sudarwin Kamur, Tri Kusmita, Surya Ningsih, Rita Desiasni http://creativecommons.org/licenses/by-sa/4.0
Penerapan Metode Elektrokoagulasi Dalam Peningkatan Kualitas Larutan FeCl3.6H2O
Electrocoagulation is a method that is often used to improve the quality of solutions. The electrocoagulation method has the advantages of not using chemical additives, easy and inexpensive operation, and having high efficiency in removing pollutants and contaminants. In this method, the pollutants obtained are easy to separate because of the floating surface of coagulated sediments called flocs. The solution used is FeCl3.6H2O solution as a source of iron content and a replacement medium for water or solutions containing iron. The iron content in water is more dominant than other heavy metals, whereas in excess it can cause health problems. In this study, a standard iron solution was used at 10 ppm variations using the electrocoagulation method using an aluminum plate at a voltage of 25 volts and a time of 60 minutes, and testing for pH, TDS, and UV-Vis was carried out. Obtained after the electrocoagulation process of the Fe standard solution, each concentration experienced an increase in quality, in the form of a significant decrease in Fe concentration (ppm), an increase in the pH value from 3 to 5, and a decrease in the TDS value of 80.69% -85.88%. So, the electrocoagulation method can be applied to improve the quality of a solution.
electrocoagulation, FeCl3.6H2O, solution quality
Copyright (c) 2024 Lizia Miratsi, Widodo Budi Kurniawan, Anisa Indriawati
Analisis Pengukuran Taraf Intensitas Bunyi Pengeras Suara Masjid Menggunakan Aplikasi Sound Level Meter
Noise pollution can come from various sources around us, such as loudspeakers. In Indonesia, where the majority of the population is Muslim, many mosques use loudspeakers to broadcast the adhan, or call to prayer. Recently, the use of mosque loudspeakers has sparked debate, as some people are concerned that the noise may disrupt their comfort and potentially affect their health. This study aims to assess whether the noise level of the adhan from these loudspeakers is within safe limits or exceeds the threshold that could harm human health. The research involved measuring the sound intensity of the adhan using a sound level meter app. Measurements were taken at two locations: within the mosque courtyard and at a distance of 100 meters from the mosque. The study examined six mosques in Bekasi City, with two mosques located in residential areas, two in office areas, and two in school areas. The results indicate that the highest noise levels were recorded in the mosque courtyards, with levels decreasing as the distance from the mosque increased. Among the six mosques, the highest noise level recorded was 84.5 dB in the mosque courtyard, which is below the threshold set by the Ministry of Manpower Regulation No. 5 of 2018, meaning it is still considered safe for human health
noise; loudspeaker; sound intensity level; sound level meter; sound waves
Copyright (c) 2024 Nurizati Nurizati, Tedi Sumardi, Iqbal Robiyana
Advances Systematic Literature Review (SLR): Kemajuan Teknik Lapisan Semprot Pada Sel Surya Ditinjau dari Aspek Efisiensi dan Prospek Komersialisasi
This systematic review examines recent developments in spray-coated solar cells through analysis of 127 peer-reviewed studies (2019-2024). Our findings highlight significant advances in ultrasonic spray techniques, achieving thickness variations of ±2.5% and perovskite-based device efficiencies reaching 21.7%. Large-scale implementation demonstrated successful coating areas of 1.5 m² while maintaining 90% of lab-scale performance. Despite promising results, stability remains challenging, with typical efficiency losses of 15-20% over 1000 hours. Current trends suggest commercial viability within 3-5 years, contingent upon advances in materials and processing techniques.
spray coating, solar cells, photovoltaics, thin film fabrication
Copyright (c) 2024 Adi Kurniawan, Anisa Indriawati
Pengaruh Konsentrasi H₂SO₄ pada Metode Hidrolisis Asam Sintesis Nanopartikel Selulosa Berbasis Limbah Kertas Konvensional
Limbah kertas pada dasarnya memiliki potensi untuk dimanfaatkan sebagai sumber selulosa dengan kandungan yang cukup tinggi sebesar 64,84%. Sintesis nanopartikel selulosa dapat dilakukan dengan proses hidrolisis asam dengan menambahkan larutan H2SO4 menghasilkan nanoselulosa berukuran 150-200×10-20 nm. Penelitian ini bertujuan untuk mengetahui karakteristik nanopartikel selulosa limbah kertas terhadap pengaruh dari perlakuan variasi konsentrasi H2SO4. Variasi sampel nanopartikel selulosa terbaik menjanjikan banyak manfaat dalam perkembangan teknologi material sebagai bahan ramah lingkungan. Selulosa diekstraksi menggunakan metode delignifikasi yang kemudian dilakukan proses hidrolisis asam dengan variasi konsentrasi H2SO4 1 M, 3 M, 5 M, dan 7 M untuk mengecilkan ukuran partikel selulosa menjadi nanopartikel selulosa. Variasi sampel diuji menggunakan FTIR, PSA dan SEM untuk mengetahui kandungan serta ukuran partikel termasuk morfologi sampel nanopartikel selulosa.
Acid hydrolysis, Waste paper, Cellulose nanoparticles
Copyright (c) 2024 Firza Roehafi, Flourenchia Charollyne Latupapua, Zundia Zundia, Herman Aldila
Identifikasi Kestabilan Tanggul Waduk Desa Kemuja Menggunakan Metode Geolistrik Resistivitas Konfigurasi Wenner
Kemuja Village Reservoir is one of the reservoirs located in Kemuja Village, West Mendo District, Bangka Regency, which was built in 2015. On the sides of the Kemuja Village Reservoir, there are embankments that are used to prevent flooding of rice fields. Based on the initial survey, the height of the embankment from the ground is ±2.6 m and the water level is ±1 m above the surface. This study aims to identify the stability of the Kemuja Village reservoir embankment based on 2D modeling using the Wenner configuration resistivity geoelectric method with a spacing of 8 m between electrodes. Based on 2D modeling, the Kemuja Village reservoir embankment has good stability on all tracks, except on track 1 at a depth of 0 m - 1 m with a measurement distance of 10 m - 14 m, track 2 at a depth of 0 m - 1 m with a measurement distance of 36 m - 40 m, track 3 at a depth of 0.5 m - 2 m with a measurement distance of 6 m - 8 m; 0 m - 1.5 m with a measurement distance of 12 m - 16 m and 0 m - 2 m with a measurement distance of 28 m - 30 m, traverse 4 at a depth of 0 m - 1 m with a measurement distance of 8 m - 10 m and 0 m - 2 m with a measurement distance of 44 m - 48 m.
Tanggul Waduk; Konfigurasi Wenner; Model 2D
Copyright (c) 2024 Tina Asisah, Yekti Widyaningrum, Anisa Indriawati
Penentuan Tingkat Resiko Gempabumi Berdasarkan Peak Ground Acceleration (PGA) di Daerah Istimewa Yogyakarta
Special Region of Yogyakarta is an areas with highest probability of earthquakes. This is caused by the movement of the Indo-Australian plate in the southern Java and the movement of local faults spread across in other area. Therefore, the Special Region of Yogyakarta is interesting to study. This study aims to determine intensity and Peak Ground Acceleration (PGA) value and then describe the potetntial impact due to future earthquakes.. Earthquake data was obtained from a database catalog of earthquake events recorded at the BMKG Geophysics Station Class I Sleman at years 2005-2015. The method used to determine the PGA is Gutenberg-Richter. The results in this study, PGA was applied by Gutenberg-Richter (PGA) value with the Gutenberg-Ritchter method has a value highest 147 gal (VII-IX MMI). The area with the potetntial impact due to future earthquake is Bantul regency.
Copyright (c) 2024 yoanda octavia http://creativecommons.org/licenses/by-sa/4.0
Identifikasi Zona Lemah Tanggul Daerah Aliran Sungai (DAS) Bumang Desa Kemuja Menggunakan Metode Geolistrik Resistivitas Konfigurasi Wenner
The Bumang Watershed is a stream of water originating from the Bumang Reservoir in Kemuja Village, Bangka Regency to hold back water from flooding the surrounding rice fields. Since the Bumang watershed embankment was built, the embankment has been damaged in the upper part of the Bumang watershed. The main cause is underground erosion. The erosion caused the embankment foundation to become weak, which was identified as a weak zone. The method used to identify weak zones in the embankment is the Wenner configuration resistivity geoelectric method. The Wenner configuration has good sensitivity to lateral changes compared to other configurations. Field data acquisition consisted of four passes with different electrode lengths and spacings. Based on the 2D cross-section of the subsurface of the Bumang watershed embankment, the weak zone is located on tracks 1, 2, and 3. On track 1 it is at a depth of 2.50 m - 3.19 m and 1.30 m - 3.19 m; on track 2 it is at a depth of 0 m - 2 m; and on track 3 it is at a depth of 0 m - 7 m, 2 m - 4.50 m, and 0 m - 4 m respectively.
watershed embankment, wenner configuration, 2D model, weak zone
Copyright (c) 2024 Dea Amelia, Yekti Widyaningrum, Anisa Indriawati
Pengaruh Temperatur Aktivasi Karbon Aktif Terhadap Adsorpsi Logam Besi (Fe) Pada Limbah Batik Cair Batik Cual
Batik cual waste is a problem that is quite dangerous if it is disposed of directly into the environment because it contains various kinds of heavy metals such as iron Fe. To overcome the problem by utilizing coconut shell as activated carbon. In this study, the activated carbon used was the result of chemical activation and physical activation processes using temperatures of , and . Based on the SEM results to determine the sphericity value for a temperature of is worth 0.47 for is worth 0.56 and for is worth 0.52. The value of the pore diameter of activated carbon at temperatures of , and is 40.11µm, 81.84µm and 55.50µm. The BET results for activated carbon have a total pore volume for temperatures of , and with values of 0.182 cc/g, 0.2315 cc/g and 0.1605 cc/g. To decadarize cual batik wastewater through the adsorption process, temperatures of , and were used with contact times of 0, 40, 80, 120 and 160 minutes. The adsorption results were carried out by kinetic modeling using first-order, second-order and BMG kinetic models. Based on the model that is most suitable for the adsorption of liquid batik wastewater is BMG
Cual Batik Liquid Waste, Activated Carbon, Adsorption Kinetics, Fe Metal
Analisis Pengaruh Penambahan Minor Aktinida Am-241 dan Np-237 pada Performa Sel Bahan Bakar Uranium Metallic U-10%wtZr
Nuclear reactors are capable of producing electricity using nuclear fuel in a sustainable system. Despite its benefits, the combustion of nuclear fuel in a reactor produces fission products known as nuclear waste. One type of nuclear waste is minor actinide, minor actinide is included in burnable poison so it can be recycled as additional fuel. This research was conducted to analyze the effect of the addition of minor actinides Am-241 and Np-237 on the burn-up performance of the Uranium Metallic U-10%wtZr fuel cell in a Gas cool-Fast Reactor with S-CO2 gas coolant and stainless steel cladding material. SS-316. The fuel pin was designed to be cylindrical with a diameter of 1.4 cm and then tested by adding 0 – 8% minor actinide to the fuel. Calculations were carried out based on the neutron transport equation using the SRAC program which produces survey parameters : Kinf value, burn-up level, conversion ratio, and atomic density throughout the burn-up period of 120 years. The results show that there is a slight increase in the Kinf value for each minor actinide addition at the beginning to the end of the burn-up period. The total atomic density of Am-241 and Np-237 in the fuel added with minor actinides decreased as the burn-up period ended. The addition of minor actinides did not have a significant effect on the neutronic performance of U-10%wtZr fuel but was able to reduce the amount of Am-241 and Np-237 elements at the end of the burn-up period.
Gas cool-Fast Reactor; Nuclear Waste; SRAC
Copyright (c) 2025 Muhamad Tauffan Hidayatullah Norman, Fiber Monado, Menik Ariani http://creativecommons.org/licenses/by-sa/4.0
Eksplorasi Endapan Bauksit Menggunakan Metode Polarisasi Terimbas dan Resistivitas di Desa Sebemban, Kalimantan Barat
Tayan Hilir District, West Kalimantan Province, Indonesia, is characterized by the presence of economically valuable mineral resources, particularly bauxite deposits. This study aims to delineate the distribution of bauxite deposits in Sebemban Village, Tayan Hilir District, using integrated geophysical approaches. The investigation employed the induced polarization (IP) and electrical resistivity methods with a dipole–dipole electrode configuration. Resistivity and chargeability measurements were conducted along three survey lines, each 156 m in length with an electrode spacing of 4 m. The results show that the resistivity values range from 45.36 to 367.177 Ω·m, while the chargeability values vary between 16.9 and 878.80 ms. The subsurface stratigraphy of the study area comprises latosol, bauxite, saprolite, and bedrock units, including granodiorite and quartz diorite. Bauxite mineralization was identified at shallow depths, commencing at approximately 0.6 m below the ground surface. These results indicate that the combined application of resistivity and induced polarization methods is effective for identifying and characterizing near-surface bauxite deposits in the study area.
Copyright (c) 2025 Handika, Yudha Arman, Muhardi Muhardi http://creativecommons.org/licenses/by-sa/4.0
Kajian Variasi Massa Karbon Aktif dan Waktu Kontak terhadap Kinetika Adsorpsi Ion Logam Besi (Fe) pada Limbah Cair Batik Cual
Cual batik liquid waste discharged directly into the environment can cause environmental problems due to containing various heavy metals such as iron metal (Fe). Adsorption method is one of the efforts to reduce heavy metal content in wastewater. This study utilises activated carbon from coconut shell waste to be used as a heavy metal adsorbent. The activated carbon used is the result of physical and chemical activation processes. Based on SEM results, activated carbon has pores with a pore diameter of 81.84 µm and a surface area of 0.2315 cc/g. The adsorption process was carried out using activated activated carbon with mass variations of 0.25 grams, 1.5 grams, and 1.75 grams. Meanwhile, the contact time variations used were 0, 40, 80, 120, and 160 minutes. The results showed that the most optimum mass variation of activated carbon to absorb Fe metal was 1.5 grams with a contact time of 80 minutes which left a residual Fe metal of 0.161 ppm.
Batik Liquid Waste, Fe Metal, Activated Carbon, Adsorption Kinetics
Copyright (c) 2024 rena aprilianti, Herman Aldila, Widodo Budi Kurniawan
Analisis b-value Gempabumi Menggunakan Metode Gutenberg-Richter Berdasarkan Estimasi Maximum Likelihood Di Daerah Sulawesi Utara
Sulawesi is an area prone to earthquakes. This is because the Sulawesi region is flanked by three main plates, namely the Pacific Ocean plate moving westward, the Australian Continental Plate moving northward, and the Eurasian Plate moving south-southeast. This situation causes a high level of seismicity in the Sulawesi region. The Sulawesi region has a fairly complex tectonic setting so that the activity of earthquakes in the Sulawesi region is also interesting to study. The level of seismicity depends on the degree of fragility of the rock (b-value) and the distribution of earthquakes in the region. This research was conducted to determine the b-value of earthquakes in the North Sulawesi region. The method used for this research is the Gutenberg-Richter method based on the Maximum Likelihood estimation. Maximum Likelihood Estimation is a method used to statistically calculate earthquake activity parameters. The software used are ArcGIS and Microsoft Excel. The research was conducted in North Sulawesi with coordinates 118° East - 125° East 1° North Latitude - 6° South Latitude. The data used is earthquake catalog data obtained from BMKG with earthquake data for a period of 10 years (2012-2021). Based on the results of the analysis of the distribution of seismicity based on magnitude, it is more towards the Sulawesi Sea and the distribution of seismicity based on depth is shallow. The result of calculating the b-value is 0.3537 and the a-value is 3.0932. It can be concluded that the North Sulawesi region has a fairly large chance of an earthquake occurring
Copyright (c) 2024 Reski Maulinda, Tri Kusmita, Herman Aldila, Triani Triani
Implementasi Sistem Keamanan Pintu Otomatis Berbasis Face Recognition di Proactive Robotic: Integrasi ESP32-Cam dan Telegram
The research focuses on implementing an automatic door lock system based on face recognition using the ESP32-Cam microcontroller and integrating it with the Telegram platform. The system is designed to enhance security at Proactive Robotic by leveraging IoT technology for office door access control. System design began with needs analysis and identification of existing security issues which do not integrate with other smart home systems at the institution. Development methods included hardware and software design, circuit schematic creation, PCB production, and physical assembly. System testing ensured facial detection, recognition, and essential solenoid operation in varying lighting conditions. Test results showed the system accurately recognizes registered faces under standard lighting, automatically unlocks doors, and sends real-time notifications via Telegram. However, system accuracy under low-light conditions needs improvement, as well as enhanced user data security to protect stored information privacy. This research contributes to developing IoT and face recognition-based security applications. The system successfully implements cutting-edge technology to improve physical security and access management in office environments, laying the foundation for future advancements in security technology.
Copyright (c) 2024 Heriyanto Syafutra, Thufeil Muhammad Nur Aziz, Inna Novianty, Irmansyah Irmansyah, Muhamad Chusnu, Dwi Prayoga
Sintesis dan karakteristik nanopartikel CaO dari cangkang kerang darah (Anadara granosa) menggunakan metode kopresipitasi
The lithium ion battery is a type of secondary battery. A good component to be used as the anode of a lithium ion battery is Li4Ti5O12 (LTO). LTO has a low conductivity value so doping is necessary. Doping particle size greatly affects the conductivity of LTO. The purpose of this doping was carried out to find out how the effect of CaO nanoparticle doping on the conductivity value of the LTO battery anode using the coprecipitation method by varying the molarity of NaOH, namely 1M, 3M and 7M. Based on the results of research on the influence of NaOH molarity, it produces different sizes of nanoparticles. The smallest nanoparticle size was obtained in the 3M sample variation, which was 175.0 nm. With a purity of CaO nanoparticles of 96.35%. While the conductivity value of the lithium ion battery doped with CaO nanoparticles with three variations of NaOH molarity, the optimum value was obtained in the 1M sample, which was 1.06 × 10-6 S/cm. This is because the 1M variation produces very low impurities compared to the 3M and 7M variations which have more impurities, this can affect the conductivity value.
Coprecipitation, Nanoparticles, Conductivity.
Nur Hayati1,*), Widodo Budi Kurniawan1, Indah Puspita1
Copyright (c) 2024 Nur Hayati, Widodo Budi Kurniawan, Indah Puspita
Literature Review: Electroculture system in accelerating plant growth and germination
In the development of agricultural or plant technology, innovations are needed to increase efficiency in the process of accelerating growth and the harvest period. The application of physics in the fields of agriculture and biology is one that can be developed. One study that is very interesting to discuss is the application of the electroculture system, which uses electricity to help speed up the growth process and harvest period, in addition to growth and development of electroculture is also claimed to be able to minimize attacks by insect pests and viruses, in this article we review several studies related to the effect of the electroculture system on plants, and from several studies we can prove the effect of applying the electroculture system in accelerating the growth and development process, there are several ways to Electroculture applications include antenna systems, direct current, alternating current, development of electrogenetic seeds and the use of electrolysis
Electroculture, plant, Literature review, Applied Physics
Copyright (c) 2024 Siti Ayu Kumala, Ahmad Jahrudin
Analisis Tingkat Kebisingan di Tempat Bermain Anak X Di Kota Palangka Raya
Children's play areas that exceed the Noise Limit Value (NTV) can cause hearing health problems, including physiological and communication disorders. Therefore, this study aims to evaluate the noise level at one of the X children's playgrounds in Palangka Raya City which is busy with visitors. This research is important for playground owners to create a safe and comfortable environment for visitors. Noise levels are measured using a sound level meter which is then analyzed to determine the average noise value at each data collection point. Based on the analysis carried out, it shows that the average noise value at children's playground X in Palangka Raya City on weekdays is 79.52 dBA, while on holidays it reaches 81.76 dBA. This value exceeds the threshold recommended by the World Health Organization (WHO) and the Indonesian Ministry of Health for recreational areas which should be in the range of 70 dB. Based on this research, it is recommended that management take mitigation steps such as using building materials that absorb sound, limiting children's play time, and providing ear protection for zones with high noise levels.
Copyright (c) 2024 Yunita Enzelina Silaban, Akhmadi Surya Nata, Uci Purnama Purba, Reni Agustiani
Identification of Mineralization Zones Using Geoelectrical Methods Self-Potential (Sp) in Pemali Village Bangka Regency
Bangka Belitung as an area that has a lot of potential natural mineral resources, especially tin minerals, this tin mineral potential can be utilized for industrial and non-industrial purposes. Utilization of these minerals can be done by way of exploration, exploration of mineral distribution can be done directly in the field using geophysical methods. In this study the method used is the geoelectric method of self-potential (Sp) fixed base configuration. Data acquisition was carried out in two research sample areas, namely, region 1 and region 2 with a distance between the porouspot electrodes as far as 5 m. Data retrieval on the rover was carried out at each point of the trajectory, three times the data was taken with an interval of 30 seconds, while the retrieval at the base in region 1 was carried out every 3 minutes while in region 2 it was carried out every 1 minute. The research is focused on identifying the distribution of mineral zones below the surface. The results of the study are in the form of a contour map that describes the distribution pattern of potential difference anomalies (Sp) and a topographical anomaly map at the research location, which will later be interpreted to determine the direction of the distribution of minerals below the surface of the study site.
Mineral; Exploration; Geophysics; self-potential (Sp)
Copyright (c) 2021 Jurnal Riset Fisika Indonesia
Penerapan Metode Geolistrik Resistivitas Konfigurasi Wenner Untuk Mengetahui Dugaan Rembesan Polutan Sampah Di Sekitar Tempat Pembuangan Akhir (TPA) Desa Tanjung Belit Kabupaten Rokan Hulu
A resistivity geoelectric research has been carried out to identify the suspected seepage of garbage pollutants around the Tanjung Belit village garbage dump. The study was conducted in 2 tracks. On track 1 with a track length of 100 m and 35 measurement points, the resistivity is in the range of 0.795-50.1 Ωm. On the 2nd track, 75 m long and 32 measuring points. The method used is the geoelectric resistivity method of the Wenner configuration with data processing using the res2dinv application which has a large resistivity ranging from 1.22-44.9 Ωm. Based on this resistivity, it can be seen that there is waste pollutant seepage located at a depth of 0.825–7.41 m. Keywords: Wenner, geolistric method, RES2DINV
Copyright (c) 2020 Jurnal Riset Fisika Indonesia
Karakteristik Karbon Aktif Limbah Kulit Lada (Piper Nigrum L) sebagai Elektroda Superkapasitor
Pemenuhan kebutuhan energi dibutuhkan suatu piranti penyimpan yang memiliki kapasitansi spresifik yang tinggi yaitu superkapasitor. Superkapasitor adalah perangkat penyimpan muatan yang memiliki kapasitansi spesifik yang tinggi. Dalam penelitian ini telah dilakukan preparasi dan karakterisasi karbon aktif dari limbah kulit lada sebagai bahan elektroda superkapasitor. Karbon diaktivasi dengan variasi aktivator NaOH 1 M, 3 M dan 5 M dilanjutkan dengan pemanasan pada suhu 700˚ C selama 3 jam dengan dialiri gas nitrogen (N2). Karbon selanjutnya dikarakterisasi menggunakan Scanning Electron Miscroscopy-Energy Dispersive Spektroscopy (SEM-EDS), Brunauer-Emmett-Teller (BET) dan pengukuran kapasitansi menggunakan metode Cyclic Voltametry (CV). Hasil pengujian menunjukkan karbon aktif limbah kulit lada berpori dengan bentuk pori bulat pada sampel 3 M dan 5 M, sedangkan pada 1 M terdapat pori berongga yang pipih dan panjang. Hasil EDS setiap sampel memiliki kandungan unsur karbon (C) secara berurut yaitu 77,57%, 75,96%, dan 74,62%. Hasil BET menunjukkan luas permukaan maksimum sebesar 149,319 m2/g. Kapasitansi elektroda superkapastitor tertinggi diperoleh pada konsentrasi 5 M dengan laju scan 1 mV/s yaitu 12,68 F/g.