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All Journal Jurnal Ilmu Dasar JURNAL ILMIAH PENDIDIKAN FISIKA AL BIRUNI Science and Technology Indonesia Journal of Science and Applicative Technology Indonesian Physical Review
Rajak, Abdul
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Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Civil Engineering, Building, Construction & Architecture Control & Systems Engineering Earth & Planetary Sciences Education Electrical & Electronics Engineering Engineering Environmental Science Materials Science & Nanotechnology Mathematics Mechanical Engineering Physics

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Effect of Calcination Temperature on the Adsorption Performance of Tanggamus Natural Zeolite for Ammonium Removal from Shrimp Pond Wastewater Al Qadri, Latif; Abelta, Gita Aldira; Febrina, Melany; Rajak, Abdul; Maulana, Sena; Asagabaldan, Meezan Ardhanu; Taher, Tarmizi
Science and Technology Indonesia Vol. 9 No. 1 (2024): January
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2024.9.1.198-206

Abstract

This research explores the potential of locally sourced natural zeolite from the Tanggamus District, Indonesia, for the removal of ammonium from shrimp pond wastewater. The study utilizes a comprehensive approach involving desilication modification, batch adsorption experiments, and field-scale application. The zeolite, predominantly composed of clinoptilolite, undergoes calcination at varying temperatures, with 200°C proving to be optimal for enhancing ammonium adsorption capacity. The study also highlights the efficient use of zeolite at a lower dosage of 5 g/L, yielding high removal efficiency. The real-world effectiveness of this method was confirmed by field experiments, where the application of calcined zeolite resulted in lower ammonium concentrations in shrimp ponds. The results demonstrate that the application method, specifically direct spreading in the ponds, affects adsorption performance. These findings underscore the potential of using Tanggamus Natural Zeolite as a cost-effective and eco-friendly solution for ammonium control in shrimp pond wastewater. This work paves the way for future research focusing on the long-term application effects and zeolite regeneration methods to further improve the economic and environmental efficiency of this approach.
Enhanced Ammonium Adsorption from Aqueous Solutions Using Ethylenediaminetetraacetic Acid (EDTA) Modified Lampung (Indonesia) Natural Zeolite: Isotherm, Kinetic, and Thermodynamic Studies Abelta, Gita Aldira; Al Qadri, Latif; Febrina, Melany; Rajak, Abdul; Maulana, Sena; Asagabaldan, Meezan Ardhanu; Taher, Tarmizi
Science and Technology Indonesia Vol. 9 No. 2 (2024): April
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2024.9.2.224-234

Abstract

The environmental concern related to excessive ammonium in water bodies necessitates efficient and cost-effective removal techniques. This study investigated the modification of natural zeolite collected from the Tanggamus district of Lampung Province, Indonesia, with ethylenediaminetetraacetic acid (EDTA) to enhance its performance for ammonium adsorption from aqueous solution. The modified and natural zeolites were characterized using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), N2 adsorption-desorption isotherm, and scanning electron microscopy (SEM). Results indicated that the modification did not cause significant structural changes but increased the mesoporosity of the zeolites, which was beneficial for ammonium adsorption. The adsorption studies revealed that the EDTA modified zeolites consistently outperformed the natural zeolite and that the adsorption process was exothermic in nature. The Langmuir and Freundlich isotherm models fit the adsorption data well, indicating that the adsorption process occurs on both homogenous and heterogeneous surfaces. Thermodynamic studies confirmed that the adsorption process was exothermic and that the EDTA modification increased the spontaneity of the ammonium adsorption process. Overall, this study highlights the potential of EDTA-modified zeolites as an effective material for ammonium removal from aqueous solutions.
The Effect of Nonwoven Microfiber Substrate Polypropylene Thickness to Air Filtration Performance of Polyacrilonitrille Nanofiber Rajak, Abdul; Syahputra, Tri Siswandi; Munir, Muhammad Miftahul; Khairurrijal, K.
Jurnal ILMU DASAR Vol 20 No 2 (2019)
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1512.963 KB) | DOI: 10.19184/jid.v20i2.9658

Abstract

Since a nanofiber medium on itself is soft and fragile and cannot be used alone as air filters. Coating nanofiber on a rigid substrate to form a composite that can be handled readily is necessary. Beside can improve the filtration efficiency, adding the substrate will also save the use of nanofibers mat itself. The aim of this study is to evaluate the effect of substrate thickness on the performance of nanofibers mat in aerosol filtration in order to find the optimum thickness of substrate that can increase the quality of nanofiber filter. The substrate used was a low cost microfiber non-woven fabric made from polypropylene (PP). The nanofibers mat was composed of electrospun polyacrylonitrile (PAN) with concentration of 9 wt.% which dissolved at N,N dimethylformamide (DMF). Five variations of PP different in thickness was used as substrate. From the SEM image, it was found that there is increasing fiber diameter of PAN after electrospun into PP substrate. From the porosity estimation of each nanofiber, it was found that the porosity decreased with increasing the substrate thickness. For test the performance of nanofiber filter, the particles of polystyrene latex (PSL) which generated by atomizer was used as the aerosol particle. In addition, to evaluate the performance filter in PM2.5 filtration, the experiment was carried out with generate the smoke from burning incense. Air filtration performance of all variations is obtained by comparison the results of measurement including: pressure drop, efficiency and quality factor. From the results, there is limitation on the substrates thickness based on the value of the quality factor obtained. Overall, PP nonwoven as the substrates gives the great contribution on the efficiency of PAN nanofiber. Keywords: substrate, polypropylene, thickness, nanofiber, air filtration.
Electrospun Nanofibers from Recycled Styrofoam: Characterization and Smoke Filtration Performance for Environmental Sustainability Rajak, Abdul; Tarigan, Chalpin Sapenta
Jurnal Ilmiah Pendidikan Fisika Al-Biruni Vol 14 No 1 (2025): Jurnal Ilmiah Pendidikan Fisika Al-Biruni
Publisher : Universitas Islam Negeri Raden Intan Lampung, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24042/jipfalbiruni.v14i1.23840

Abstract

Cigarette smoke pollution contains PM₂.₅ particles with sizes ranging from 0.1 to 2.5 µm, along with nicotine and tar, while conventional filters have limited effectiveness in capturing ultrafine pollutants. The increasing use of Styrofoam in various industries has contributed to environmental challenges due to its resistance to natural degradation and limited recycling. This study develops an electrospun nanofiber-based cigarette smoke filter from recycled Styrofoam by optimizing electrospinning parameters to achieve controlled fiber morphology and enhanced filtration. Optimized parameters—including applied voltage, flow rate, needle-to-collector distance, viscosity, and solution concentration—enabled the fabrication of nanofibers with uniform morphology. SEM characterization revealed fiber diameters ranging from 0.88 to 2.23 µm, with a basic weight of 0.005–0.009 g/cm², thickness of 0.007–0.016 cm, and porosity of 61–76%. Filtration tests demonstrated PM₂.₅ capture, with visible tar deposition turning the nanofibers yellow-brown. Nanofiber mass increased post-filtration, correlating with contact time variation. Post-filtration FTIR analysis revealed peak shifts at 3377–3413 cm⁻¹ (OH stretching) and 1447 cm⁻¹ (NH bending), indicating nicotine and tar adsorption. These findings demonstrate that electrospun styrofoam-derived nanofiber membranes provide an effective alternative for cigarette smoke filtration, offering high efficiency and a sustainable approach to plastic waste reduction
PENGEMBANGAN SISTEM TERINTEGRASI BERBASIS IOT (INTERNET OF THINGS) UNTUK MONITORING DAN KONTROL KUALITAS AIR PADA BUDIDAYA TAMBAK UDANG DARATAN Sari, Titin Ervina; Satria, Eko; Rajak, Abdul
Journal of Science and Applicative Technology Vol. 8 No. 1 (2024): Journal of Science and Applicative Technology June Chapter
Publisher : Lembaga Penelitian dan Pengabdian Masyarakat (LPPM), Institut Teknologi Sumatera, Lampung Selatan, Lampung, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35472/jsat.v8i1.1698

Abstract

Water quality is very important for the sustainability of a shrimp farm, starting from the quantity and quality of shrimp harvested is very influential on the good quality of the pond water. The water quality in question is parameters such as water turbidity, a lot or clean of dirt in the pool, a pH value that suits your needs and ammonia content in the pond which is usually produced from shrimp manure. This research designed a water quality monitoring and control tool in shrimp ponds that is integrated automatically through an IoT-based system (Internet of Things) using the thingspeak application as a server and telegram bots as controls. Based on the results of tests that have been carried out, the tool has been able to determine the quality of water correctly. The error percentage was 0.01% for turbidity sensors, 0.05% for TDS sensors, 0.01% for pH sensors and 0.12% for ammonia gas sensors. Based on the results of direct data collection on shrimp ponds for 6 hours, the average value of water turbidity was 3.06 NTU, the lowest was 1.07 NTU and the highest was 5.99 NTU, for the average value of TDS content was 170.98 ppm, 150.00 ppm was the lowest and 204.12 ppm was the highest, for the average pH content was 7.80, the lowest was 7.50 and the highest was 8.74, and the average value of ammonia content was 0.004 ppm, 0.0007 ppm is the lowest and 0.0113 is the highest.
FIRST-PRINCIPLES STUDY OF MAGNETIC ANISOTROPY ENERGY IN TWO-DIMENSIONAL FERROMAGNETIC CrI3 Mecci, Puke Lajaladita Litle; Monica, Annisa; Sinurat, Iin Riananda Br; Widiyani, Agustina; Rajak, Abdul; Pardede, Indra
Indonesian Physical Review Vol. 6 No. 1 (2023)
Publisher : Universitas Mataram

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29303/ipr.v6i1.191

Abstract

First-principles calculations are increasingly crucial in searching for new materials with customized properties or new functionality. First-principles calculations are superior in speed and cost, and comparable to experiments in terms of accuracy. Two-dimensional (2D) ferromagnetism materials were successfully fabricated experimentally in atomic thin films of CrI3. 2D intrinsic ferromagnetism with perpendicular magnetic anisotropy energy (PMAE) is an encouraging applicant compatible with high-density magnetic storage applications. In this study, spin density functional calculations are investigated on the magnetic anisotropy energy (MAE) in 2D monolayer ferromagnetic CrI3 using a first-principles electronic structure calculation. We include the MAE part calculation from the magnetocrystalline anisotropy energy (MCAE) that comes from the spin-orbit coupling (SOC). In the present calculation, the MCAE part, in addition to a usual scheme of total energy (TE), was evaluated using a grand-canonical force theorem (GCFT) scheme. The MCAE of 2D monolayer ferromagnetic CrI3 is 1.7 meV/unit cell and verified it has an easy-axis perpendicular to the crystal plane, which is a good agreement with experimental measurement. In the latter scheme, employing GCFT, we evaluated atom-resolved, k-resolved, and atomic k-resolved analyses for MCAE can be performed. From the GCFT result, the Cr atom indicates that it is the primary origin of PMAE in the atom-resolved MCAE. The negative MCAE contribution is in points, and the positive MCAE is mainly placed at the line in the 2D first Brillouin zone. Our systematic calculation in this work may also help design an effective structure of monolayer CrI3 in new 2D material magnetic sensor and spintronic device designs.
Kajian First Principles tentang Sifat Elektronik dan Optik Semikonduktor ZnO dengan co-doping CoX (X = Cr, Mn, Ti, V) Prayoga, Harry; Rajak, Abdul; Widiyani, Agustina; Prayogo, Priyan; Musfiroh, Fatimatul; Pardede, Indra
Indonesian Physical Review Vol. 9 No. 1 (2026)
Publisher : Universitas Mataram

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29303/ipr.v9i1.530

Abstract

The development of solar energy materials is essential for achieving the Sustainable Development Goals (SDGs). However, their performance is often limited by the electronic and optical properties of commonly used semiconductors. Unlike previous DFT studies mostly focused on non–transition metal dopants (e.g., Al, Ga), this work explores pristine ZnO, single cobalt (Co) doping, and CoX (X = chromium (Cr), manganese (Mn), titanium (Ti), and vanadium (V)) codoping to reveal how single and dual 3d-orbital interactions modify its electronic and optical behavior. This study investigates the effects of transition metal codoping CoX (X = Cr, Mn, Ti, V) on ZnO using Density Functional Theory (DFT) and DFT with Hubbard U correction (DFT+U) within the Generalized Gradient Approximation (GGA) to evaluate opto-electronic properties. The bandgap of pristine ZnO was calculated as ~0.80 eV with standard DFT, while ZnO-Co and ZnO-CoX exhibited zero bandgap with a flatband due to conduction band overlap with the Fermi level, indicating metallic behavior resulting from d-orbital contributions. DFT+U improved the pristine ZnO bandgap to ~1.08 eV, although Co-doped and CoX co-doped remained metallic. Orbital resolved analysis shows that Ti and V introduce states near the valence band, while Cr and Mn shift states deeper below the Fermi level, reflecting distinct d-orbital interactions. The theoretical band gaps underestimated experimental values due to strong electron correlation in ZnO. Optical analysis revealed that Co and CoX codoping shifts the absorption edge into the visible range and enhances the absorption intensity. The presence of dopants alters the electronic band structure and enhances optical absorption in the visible range, underscoring their effectiveness in engineering ZnO-based semiconductors for optimized optoelectronic responses.
Co-Authors Abelta, Gita Aldira Al Qadri, Latif Asagabaldan, Meezan Ardhanu Eko Satria Febrina, Melany Indra Pardede Khairurrijal Khairurrijal Maulana, Sena Mecci, Puke Lajaladita Litle Monica, Annisa Muhammad Miftahul Munir Musfiroh, Fatimatul Prayoga, Harry Prayogo, Priyan Sari, Titin Ervina Sinurat, Iin Riananda Br Syahputra, Tri Siswandi Tarigan, Chalpin Sapenta Tarmizi Taher Widiyani, Agustina