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All Journal CHEESA: Chemical Engineering Research Articles Nusantara Science and Technology Proceedings Inovasi Fisika Indonesia (IFI) Faraday: Journal of Fundamental Physics, Research, and Applied Science
Reffany Choiru Rizkiarna
Departement Of Physics, Faculty Of Engineering, Universitas Pembangunan Nasional “Veteran” Jawa Timur, Surabaya 60294, Indonesia
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Establishing Pollution Levels and Monitoring Air Quality in Eastern Indonesian Mining Areas Nur Aini Fauziyah; Billy Sopater Maniani; Reffany Choiru Rizkiarna; Fajar Timur; Arum Sinda Santika
Nusantara Science and Technology Proceedings 5th International Conference Eco-Innovation in Science, Engineering, and Technology
Publisher : Future Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11594/nstp.2024.4510

Abstract

This study aims to measure pollution levels and track the state of the air in Eastern Indonesia's major mining districts. Eastern Indonesia's mining in-dustry has significantly boosted the local economy in the area. But this also brings up environmental issues, particularly with relation to pollution and air quality. The level of sulfur dioxide (SO2), nitrogen dioxide (NO2), and other pollutants is measured using the EPM-Manual 42iQ Continuous Air Quality monitoring tool in this air quality inspection method. Our research reveals higher than expected pollution levels around mining activities, sur-passing both national and international air quality regulations. The study also shows that pollution concentrations vary seasonally, with higher levels during the dry season. Furthermore, health risk assessments show possible negative effects on locals.
RANCANG BANGUN BIDAI ORTOPEDI PINTAR BERBASIS 3D PRINTING DENGAN WIRELESS REAL-TIME MICROCLIMATE MONITOR timur, fajar; Rizkiarna, Reffany Choiru; Wardhani, Primasari Cahya; Sujiwa, Akbar; Prasetya, Bayu
Inovasi Fisika Indonesia Vol. 14 No. 2 (2025): Vol 14 No 2
Publisher : Prodi Fisika FMIPA Universitas Negeri Surabaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26740/ifi.v14n2.p216-223

Abstract

Abstrak Imobilisasi ortopedi merupakan bagian penting dalam proses penyembuhan patah tulang atau fraktur. Bidai merupakan alat yang digunakan untuk proses imobilisasi patah tulang atau fraktur dan umumnya berbahan dasar gips dan fiberglass. Bidai jenis ini sering menyebabkan komplikasi kulit akibat penumpukan panas dan kelembapan di bawah permukaan bidai. Kondisi mikroklimat dengan suhu dan kelembapan tinggi dapat memicu maserasi kulit, bau tidak sedap, dan infeksi sekunder yang memerlukan intervensi medis. Penelitian ini dilakukan dengan maksud mengembangkan prototipe bidai ortopedi biofungsional berbasis 3D Printing yang dilengkapi modul sensor suhu dan kelembapan yang ditransmisikan secara wireless.  Hasil pengujian menunjukkan bahwa prototipe bidai memiliki kekuatan tekan yang lebih tinggi dibandingkan bidai gips. Uji pemantauan waktu nyata selama dua jam dilakukan pada relawan sehat dengan suhu lingkungan 25 °C menunjukkan bahwa suhu internal bidai berada pada rentang 30–31,2 °C dan kelembapan relatif 64–66%, dengan deviasi ≤1,3% terhadap alat referensi dan nilai p > 0,05 untuk seluruh titik waktu. Fluktuasi suhu dan kelembapan yang diamati mencerminkan dinamika termal fisiologis dan efektivitas ventilasi pada struktur bidai. Prototipe bidai ini menunjukkan kemajuan penting dalam perawatan ortopedi dengan meningkatkan kenyamanan pasien patah tulang, mengurangi komplikasi kulit, dan mengintegrasikan rekayasa biomedik dengan teknologi kesehatan digital.   Abstract Orthopedic immobilization plays a critical role in the healing process of bone fractures. Casts are commonly used to immobilize fractured bones and are traditionally made from materials such as plaster of Paris or fiberglass. However, these conventional casts often cause skin-related complications due to the buildup of heat and moisture beneath the surface. An enclosed microclimate with elevated temperature and humidity can lead to skin maceration, unpleasant odor, and secondary infections that require clinical intervention. The present study aims to develop a biofunctional orthopedic cast prototype fabricated via 3D printing, equipped with embedded temperature and humidity sensors capable of wireless data transmission. Mechanical testing demonstrated that the 3D-printed cast exhibited higher compressive strength compared to traditional plaster-based casts. A two-hour real-time monitoring test was performed on a healthy volunteer in a controlled environment (25 °C). The internal microclimate within the cast ranged from 30 to 31.2 °C with a relative humidity of 64–66%, showing a deviation of no more than 1.3% compared to calibrated reference instruments (p > 0.05 for all time points). The observed fluctuations in temperature and humidity reflect the physiological thermal dynamics of the skin and the effectiveness of the lattice ventilation design. Overall, the developed prototype represents a notable advancement in orthopedic care by improving patient comfort, reducing the risk of skin complications, and integrating biomedical engineering with modern digital health technologies.
PEMODELAN KOMPUTASIONAL SIFAT MEKANIK THIN FILM BERBASIS PEKTIN KULIT DURIAN Rizkiarna, Reffany Choiru; Timur, Fajar; Sujiwa, Akbar; Wardhani, Primasari Cahya
Inovasi Fisika Indonesia Vol. 14 No. 2 (2025): Vol 14 No 2
Publisher : Prodi Fisika FMIPA Universitas Negeri Surabaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26740/ifi.v14n2.p209-215

Abstract

Abstrak Pektin yang diekstrak dari kulit durian merupakan salah satu bentuk pemanfaatan limbah biomassa berpotensi tinggi sebagai material ramah lingkungan, khususnya untuk aplikasi kemasan pangan biodegradable. Pada penelitian ini dilakukan simulasi numerik berbasis COMSOL Multiphysics untuk menganalisis perilaku mekanik film tipis pektin kulit durian di bawah berbagai kondisi pembebanan. Studi dilakukan dengan membangun model tiga dimensi (3D) film tipis, kemudian pemetaan tegangan von Mises, analisis distribusi tegangan, serta evaluasi nilai tegangan maksimum (peak stress), minimum, dan rata-rata. Hasil simulasi menunjukkan distribusi tegangan tidak merata di seluruh volume film, melainkan terkonsentrasi pada tepi dan sudut akibat efek geometri. Nilai peak stress berfluktuasi terhadap waktu dan cenderung meningkat pada siklus pembebanan tertentu, yang berimplikasi pada potensi inisiasi retakan di area kritis. Meskipun demikian, sebagian besar area film masih berada dalam kondisi elastis, sehingga deformasi bersifat reversibel. Analisis ini menegaskan bahwa ketahanan jangka panjang film tipis pektin dipengaruhi oleh kombinasi sifat intrinsik material, kondisi batas, serta variasi pembebanan. Temuan ini memberikan dasar penting bagi pengembangan material kemasan berbasis pektin kulit durian yang lebih andal melalui modifikasi struktur maupun penambahan aditif penguat.   Abstract Pectin extracted from durian rind represents a promising valorization of biomass waste with potential applications as an eco-friendly material, particularly for biodegradable food packaging. In this study, a COMSOL Multiphysics-based numerical simulation was conducted to investigate the mechanical behavior of durian rind pectin thin films under various loading conditions. A three-dimensional (3D) thin-film model was developed, followed by von Mises stress mapping, stress distribution analysis, and evaluation of maximum (peak stress), minimum, and average stress values. The results revealed that stress distribution was not uniform across the film volume but concentrated along the edges and corners due to geometric effects. Peak stress exhibited temporal fluctuations and tended to increase during specific loading cycles, indicating a high probability of crack initiation in critical regions. Nevertheless, the majority of the film remained within the elastic regime, allowing reversible deformation. This analysis highlights that the long-term reliability of durian pectin thin films is strongly governed by the interplay of intrinsic material properties, boundary conditions, and loading variations. The findings provide a scientific basis for further optimization of durian rind pectin films through structural modification or reinforcement additives to enhance their performance as sustainable packaging materials.
The Impact of Plate Length and Material Variations on Tibial Bone Implants Analysis using Computational Biomechanics Sakinah, Sakinah; Wardhani, Primasari Cahya; Rizkiarna, Reffany Choiru; Aminallah, Deliana Nurfauziyyah; Aruan, Nenni Mona; Billah, Zakiyah Dania
Faraday: Journal of Fundamental Physics, Research, and Applied Science Vol. 1 No. 1 (2025): Faraday: Journal of Fundamental Physics, Research, and Applied Science
Publisher : Universitas Pembangunan Nasional "Veteran" Jawa Timur

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33005/faraday.v1i1.2

Abstract

The aim of this research is to simulate the strength of the implant plate, as a method for healing tibia fractures by combining bone with a bone plate. Then model and analyze using ANSYS software to analyze loads such as deformation and the maximum distribution of von Mises stress values. The results of the Maximum Principal Stress analysis on the cobalt-chromium implant plate show a minimum value of -1.2527107 Pa (-12.527 MPa) and a maximum value of 7.57610 7Pa (75.76 MPa). Based on the research results, Co-Cr material has significant advantages compared to steel as an implant material. In addition, this material has excellent corrosion resistance and very good biocompatibility, making it safe for long-term use in the human body without significant risk of allergic reactions or irritation.
Monitoring of Raw and Treated Water Quality Based on Nitrate Parameter at Ngagel Water Treatment Plant Using Spectrophotometry Method Sudrajat, Oka Akbar; Wardhani, Primasari Cahya; Timur, Fajar; Pravitasari, Rizky; Rizkiarna, Reffany Choiru; Perwitasari, Devina Rayzy
Faraday: Journal of Fundamental Physics, Research, and Applied Science Vol. 1 No. 1 (2025): Faraday: Journal of Fundamental Physics, Research, and Applied Science
Publisher : Universitas Pembangunan Nasional "Veteran" Jawa Timur

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33005/faraday.v1i1.6

Abstract

This research focuses on monitoring the water quality at the Ngagel Water Treatment Plant in Surabaya by analyzing the nitrate (NO₃⁻) content in both raw and treated water. Nitrate is a key indicator of water pollution, often originating from agricultural runoff, sewage, and industrial discharge. Samples were collected monthly from January to March 2024 at two locations: the raw water intake from the Surabaya River and the treated water output ready for distribution. Laboratory testing using spectrophotometric methods showed that nitrate levels in raw water ranged between 2.44 mg/L and 3.50 mg/L, while treated water showed a slightly lower range between 2.00 mg/L and 3.00 mg/L. These results indicate a consistent reduction in nitrate concentrations after treatment, demonstrating the efficiency of the Ngagel Water Treatment Plant’s processes. Importantly, all measured values were significantly below the maximum allowable limit of 50 mg/L, as stated in the Indonesian Ministry of Health Regulation No. 492/MENKES/PER/IV/2010. This confirms that the treated water is safe for human consumption with regard to nitrate levels. The study highlights the importance of continuous water quality monitoring to ensure public health protection and to maintain the effectiveness of water treatment facilities over time.
Hexavalent Chromium Reduction of Artificial Waste Using Resin Immobilized Photocatalyst TiO2 Wibisono, Moch. Andy; Hidayah, Euis Nurul; Ethiraj, Baranitharan; Rizkiarna, Reffany Choiru
CHEESA: Chemical Engineering Research Articles Vol. 8 No. 2 (2025): In Progress
Publisher : Universitas PGRI Madiun

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25273/cheesa.v8i2.23078.86-92

Abstract

Photocatalysis is a process that can be used to reduce hexavalent chromium in wastewater. Therefore, this study aimed to analyze the effect of a semiconductor in the form of Resin Immobilized Photocatalyst (RIP)-TiO2 on the reduction of Cr (VI), as well as the effect of pH and catalyst mass. In the process, RIP-TiO2 was produced using rutile crystal TiO2 and cation resin. The study was conducted in a column bed with continuous flow and UV lamp irradiation. Sampling was performed every 5, 15, 45, and 60 minutes, as well as the use of 30 and 40 g of RIP-TiO2. The statistical results from a Two-Way Analysis of Variance (ANOVA) showed no significant differences in pH variation and catalyst mass. However, the best operating conditions were obtained at pH 5 and a catalyst mass of 40 g with a removal rate of 21.32%. These results suggested that pH adjustment had no significant effect on the reduction of Cr(VI) to Cr(III) using RIP-TiO₂ catalyst in the photocatalytic process. Further studies are needed to evaluate other factors, such as UV light intensity, contact time, and physical characteristics of the catalyst, capable of improving the efficiency of the RIP-TiO₂ system.
Review: Synthesis of rGO in Its Use as Thin Films with Various Polymer Matrices Hidayah, Rahma Alya; Aruan, Nenni Mona; Fauziyah, Nur Aini; Rizkiarna, Reffany Choiru; Margareta, Alfriana
Faraday: Journal of Fundamental Physics, Research, and Applied Science Vol. 2 No. 1 (2026): Faraday: Journal of Fundamental Physics, Research, and Applied Science
Publisher : Universitas Pembangunan Nasional "Veteran" Jawa Timur

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Reduced graphene oxide (rGO) is a two-dimensional carbon material that has been widely developed as a functional filler in polymer-based thin films due to its high surface area, good electrical conductivity, and adequate interface compatibility. This article presents a literature review on the synthesis of rGO and its use as thin films with various polymer matrices, namely polyaniline (PANi), poly(vinylidene fluoride) (PVDF), poly(vinylidene fluoride–trifluoroethylene) [P(VDF-TrFE)], and chitosan. The review was conducted on open access scientific articles discussing rGO synthesis methods, thin film fabrication techniques, and structural, morphological, thermal, and electrical characterization of composite materials. The results of the study show that rGO can improve the functional performance of polymer thin films through the formation of conductive networks, strengthening of interface interactions, and crystal nucleation effects. In the PANi matrix, rGO increases electrical conductivity and stability, while in PVDF and P(VDF-TrFE), rGO promotes the formation of electroactive crystalline phases that enhance piezoelectric properties. Meanwhile, in chitosan, strong interfacial interactions improve electrochemical response and the potential for environmentally friendly sensor applications.
Co-Authors Akbar Sujiwa Aminallah, Deliana Nurfauziyyah Aruan, Nenni Mona Arum Sinda Santika Billah, Zakiyah Dania Billy Sopater Maniani Ethiraj, Baranitharan Euis Nurul Hidayah Fajar Timur Hidayah, Rahma Alya Margareta, Alfriana Nur Aini Fauziyah Nur Aini Fauziyah Perwitasari, Devina Rayzy Prasetya, Bayu Pravitasari, Rizky Primasari Cahya Wardhani Sakinah Sakinah Sudrajat, Oka Akbar Wibisono, Moch. Andy