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Science and Technology Indonesia
Published by Universitas Sriwijaya
ISSN : 25804405     EISSN : 25804391     DOI : -
Core Subject : Science, Social, Engineering,
Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Environmental Science Materials Science & Nanotechnology Physics
An international Peer-review journal in the field of science and technology published by The Indonesian Science and Technology Society. Science and Technology Indonesia is a member of Crossref with DOI prefix number: 10.26554/sti. Science and Technology Indonesia publishes quarterly (January, April, July, October). Science and Technology Indonesia is an international scholarly journal on the field of science and technology aimed to publish a high-quality scientific paper including original research papers, reviews, short communication, and technical notes. This journal welcomes the submission of articles that covers a typical subject of natural science and technology such as: > Chemistry > Biology > Physics > Marine Science > Pharmacy > Chemical Engineering > Environmental Science and Engineering > Computational Engineering > Biotechnology Journal Commencement: October 2016
Arjuna Subject : -
Articles 551 Documents
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Identifying the Original Source of Megalithic Stones in Tambunan Using Spectral Signature Technique Eboy, Oliver Valentine; Sieng, Kong Teck; Kemarau, Ricky Anak
Science and Technology Indonesia Vol. 9 No. 4 (2024): October
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.2024.9.4.941-948

Abstract

Megalithic stones are a remnant of the ancient people. An intriguing megalithic stone legacy ought to emphasize the context in which it fits. Consequently, it is necessary to ascertain each megalithic stone’s historical context. This is significant for the archaeologist to obtain true and valid information. In Tambunan, there are numerous myths about megalithic stones. As a result, it is impossible to verify the story’s validity. These days, remote sensing has emerged as a crucial technical instrument for archaeologists to gather spatial data in both broad and localized locations. Prior research has demonstrated the efficacy of remote sensing in identifying archaeological site remnants. Nevertheless, there have never been any investigations utilizing remote sensing in relation to small-sized megalithic stones. Thus, this study employs spectral signature techniques and remote sensing to identify the original source of the megalithic stones discovered in Tambunan. This study carries out the spectral signature of megalithic stones in Tambunan using Sentinel-2A satellite image data with a 5-meter resolution using the SNAP application. Before that, the coordinates and measurements for each megalithic stone were obtained from the ground. The spectral signature of all the megalithic stones was then compared with the spectral signature of the stones near the river or near the hill. The study’s findings demonstrate that the spectral signature of the megalithic stones in question is identical to the stone found in the river near its location. As a result, this study was successful in providing scientific evidence that the river is the source of the megalithic stones in Tambunan, despite the stones’ considerable distance from their site.
Optimization of Nanoemulsion Formula Containing Erythromycin with VCO and Varying Concentrations of Tween-80 and PEG-400 Mardiyanto; Mohadi, Risfidian; Fithri, Najma Annuria; Kurniawan, Gilang
Science and Technology Indonesia Vol. 9 No. 3 (2024): July
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.2024.9.3.697-709

Abstract

Erythromycin, a macrolide antibiotic is classified into Biopharmaceutical Classification System (BCS) class II which has low solubility in water. The low solubility corresponds to the bioavailability in the blood. One strategy to increase the solubility of Erythromycin is the formulation of erythromycin in nanoemulsion. This research aims to form nanoemulsion using the PIT (Phase Transition Temperature) method for obtaining the optimum formula of erythromycin nanoemulsion using virgin coconut oil (VCO) can be found with varying concentrations of Tween 80 surfactant and PEG 400 cosurfactant. The selection of the optimum formula was assisted by Design Expert software with the Factorial design method 22. The basis for determining the optimum formula is based on the results of organoleptic characterization tests, adsorption efficiency (%EE), percent transmittance, viscosity test, pH test, and stability test. The optimum formula was nanoemulsion which had a concentration of Tween 80 25% and PEG 400 25% as a desirability value of <1. The results of the optimum formula showed that the particle size was 170.6±12.8594 nm, polydispersity index (PDI) 0.403±0.04406, and zeta potential -8.8667±0.25697 mV and had an appropriate stability without phase separation during stability test.
Diamagnetic to Ferromagnetic Like Transition of Non-Stoichiometry Barium Titanate (BaTiO3-x) Prepared by Sol-gel Method Soegijono, Bambang; Susetyo, Ferry Budhi; Notonegoro, Hamdan Akbar; Raksa, Teguh Yoga
Science and Technology Indonesia Vol. 9 No. 4 (2024): October
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.2024.9.4.876-883

Abstract

The oxygen vacancy properties are significant, creating ferromagnetic properties of material in metal oxide systems like dilute magnetic semiconductors. An aqueous sol-gel method has been used in the present study to synthesize non-stoichiometry BaTiO3-x polycrystalline. In an attempt of examining the oxygen deficiency consequences on the magnetic properties, the gel samples were sintered (1000◦C) at various times (6, 12, 18, and 24 hours) under a vacuum environment. This study employs an X-ray diffraction apparatus in terms of characterizing segments and structures of the samples. It also investigates morphology and element distribution on the surface of the samples exploiting an Electron microscope where Energy dispersive spectroscopy is supplied. For the purpose of characterizing the magnetic properties of the samples, it applies vibrating sample magnetometers. The chemical state of the element and its corresponding bond to other elements was identified using X-ray photoelectron spectroscopy. Single-phase compounds were observed. The crystal system is tetragonal, but the crystal parameters are different. Increase sintering time leads to increase crystallite size and decrease in micro strain. Moreover, sintering in a vacuum environment results in oxygen deficiency and leads to the atomic ratio of Ba/Ti change as the sintering time increases. The Ba/Ti ratio change affects the transformation from diamagnetic to ferromagnetic-like. The elements (Ba, Ti and O) chemical state is shown and its bonding to the corresponding element along with the X-ray photoelectron spectroscopy pattern of the BTX2 sample. The element of oxygen binds to Ti and Ba while Ba element exists in two chemical states.
A Graphene Oxide Nano-Sheets: A Novel Eco-Friendly Approach for Tissue Engineering and Antibacterial Applications in Bone Disease Abdullah, Hind W.; Mubarak, Tahseen H; Resan, Kadhim K.
Science and Technology Indonesia Vol. 9 No. 4 (2024): October
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.2024.9.4.806-817

Abstract

Obtaining novel scaffolds on bone disease-affected cells with osteoconductivity has recently been the focus of tissue engineering methodologies. Chemical treatment and microwave radiation form a novel strategy to create graphene oxide nanosheets (Gns) that decorate carbon crystal structures. This approach is proven to be eco-friendly. Gns was characterized using "X-ray diffraction, ultraviolet, and Fourier transform infrared spectrophotometers". The XRD spectra confirmed the crystalline structure of Gns. The Gns product was analyzed using "Raman spectroscopy. Transmission electron microscopy and field-emission scanning electron microscopy" exposed few layered surfaces of Gns. The TEM images showed Gns specifically decorated with carbon nanoparticles. The evidence demonstrated the novelty of Gns as a very effective bactericidal agent, suggesting its potential as a future antibacterial agent. Different concentrations of Gns and its derivatives showed different cell viabilities toward various cell lines, demonstrating the dependency of a biocompatible environment for good attachment on MG63 cells.
Synthesis and Characterization of Ni(II) Schiff Base Complex as a Precursor for NiO Nanoparticles and an Investigation of Their Corrosion Inhibition Raji, Shahad Qasim; Bader, Ali Talib
Science and Technology Indonesia Vol. 9 No. 4 (2024): October
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.2024.9.4.914-928

Abstract

This study first aimed to synthesize and characterize a [Ni(C14H13NO2)(OAC)2(H2O)2] via the preparation of a ligand, coordination with Ni(II) ions, and full characterization, such as "FTIR, 1H and 13C-NMR, UV-Visible spectroscopy; and ESI-mass spectrometry" The Nickel complex was then used as a precursor to prepared NiO Nps by calcination at 450°C. The phase purity, crystalline structure, and morphological characterizes of the NiO nanoparticles were investigated via X-ray diffraction (XRD), FESEM, and FTIR spectroscopy, revealing them to be cubic system with an average crystalline is 26 nm. The preparation technique is facile, cost-effective, and rapid and suitable for generating NiO nanoparticles for use in industrial processes. Further, the corrosion inhibition effectiveness of all synthesized compounds on mild steel in 1 M HCl was evaluated. Their inhibition efficiencies were determined via potentiodynamic polarization studies, revealing the highest inhibition efficiency for the NiO nanoparticles compared to the Nickel complex and free a ligand.
Thermal Conversion of Coral Waste and its Utilization as Low-Cost Catalyst for Biodiesel Production Widianingsih, Suci; Yanti , Ika; Kamari, Azlan; Fatimah, Is
Science and Technology Indonesia Vol. 9 No. 4 (2024): October
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.2024.9.4.866-875

Abstract

This study investigates the thermal conversion of waste coral and its utilization as a heterogeneous catalyst for biodiesel production from soybean oil. In this work, waste coral is calcined at varied temperatures of 800, 900, and 1000°C, and the effect of the calcination temperature on the physicochemical character of the solid is evaluated through Fourier-transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and basicity measurement. The results show that the higher temperature facilitates the conversion of CaCO3 of the aragonite and calcite phases in raw waste coral into CaO, achieving a complete conversion at the temperature of 1000°C. Thermal conversion influences the increased surface basicity of the solid, which is associated with the higher activity for biodiesel production. Further studies on the obtained CaO as a catalyst demonstrate the catalyst dosage and the methanol-to-oil ratio as significant factors for fatty acid methyl ester production. The highest yield of 98.7% is achieved after a 3 hours reaction with 8 wt.% catalyst dosage and 9:1 methanol-to-oil ratio. The catalyst exhibits stability with an insignificantly decreased yield until the fifth usage cycle. The optimum conditions and reusability features of the calcined waste coral suggest that waste coral is a favorable CaO catalyst source for biodiesel production.
Metabolic Profiling, Antioxidant, and Anti-lipase Activity from Combined Leaves Extracts of Tamarindus indica and Murraya paniculata: A Simplex Lattice Design Approach Sholikhah, Eti Nurwening; Wiyono, Tri; Pratiwi, Woro Rukmi
Science and Technology Indonesia Vol. 9 No. 4 (2024): October
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.2024.9.4.828-839

Abstract

Tamarindus indica leaves are recognized for their potent antioxidant and hypolipidemic properties, whereas Murraya paniculata leaves are known for their abilities to lower lipids and glucose levels. This study aimed to assess the combined extract of both leaves against pancreatic lipase inhibition and analyze their metabolomic profiles as an initial step toward developing a polyherbal treatment for hypertriglyceridemia. The extracts were subjected to Liquid Chromatography-High Resolution Mass Spectrometer (LC-HRMS) untargeted system coupled with Compounds Discoverer software to reveal their metabolomic profile. Subsequently, both individual extracts and their combination were evaluated for anti-lipase activity using pancreatic lipase enzyme with p-nitrophenyl butyrate as the substrate. The combination of the two extracts (0-300 μg/mL, 300 μg/mL in total) was prepared following the Simplex Lattice Experimental Design with 5 different composition variations. Results: The findings indicated that Tamarindus indica leaf extract (TIE) predominantly exhibited lipase inhibitory activity. Interestingly, the addition of Murraya paniculata extract (MPE) diminished this enzyme inhibitory effect. TIE was found to be rich in polyhydroxy flavonoids followed by fatty amides, whereas MPE contained mainly polymethoxy flavonoids, fatty amides, and coumarins. The presence of fatty amides in both extracts was identified as a potential cause for this incompatibility. In summary, Tamarindus indica leaf extract demonstrated strong lipase inhibition; however, its effectiveness was reduced when combined with Murraya paniculata extract, possibly due to primary fatty amides. Further research is necessary to explore strategies for eliminating these compounds and confirming their impact in vivo.
Phytoestrogens Therapy for Osteoporosis Treatment Using Indonesian Medicinal Plants: A Brief Review Sianipar, Rut Novalia Rahmawati; Iswantini, Dyah; Charlena, Charlena; Wahyudi, Setyanto Tri; Prasetyo, Joni
Science and Technology Indonesia Vol. 9 No. 4 (2024): October
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.2024.9.4.949-964

Abstract

A problematic bone remodeling cycle is known to produce more osteoclasts than osteoblasts, making bones more fragile and this condition shows osteoporosis. In this context, estrogen deficiency in the human body is associated with the regulation of osteoporosis. Therefore, this study aimed to investigate the knowledge about basic concepts of bone, osteoporosis, phytoestrogens, and Indonesian medicinal plants for osteoporosis treatment. Data were obtained from literature on various databases including Science Direct, Wiley Online Library, Scopus, Pubmed, and Google Scholar. Adequate therapy is needed to increase estrogen content and an effective approach is to consume medicinal plants that contain phytoestrogens, which have identical structure and activity to human estrogen (17β-estradiol). The results showed that there were observations comprising in vitro, in vivo, and in silico studies on 18 Indonesian medicinal plants as antiosteoporosis treatments. The Leguminosae or Fabaceae family, which has a significant amount of isoflavones (the primary group of phytoestrogens) was found to dominate as an antiosteoporosis agent. Therefore, the development of phytoestrogens therapy from Indonesian medicinal plants must be implemented for the future treatment of osteoporosis.
Carbon Micron-size Content Dependency in Epoxy/Carbon Composite Coated onto SPCC Plate for Automotive Bodies Protection Anggrainy, Rani; Susetyo, Ferry Budhi; Lubi, Ahmad; Yudanto, Sigit Dwi; Rosyidan, Cahaya; Soegijono, Bambang; Ajiriyanto, Maman Kartaman; Kurniawan, Ova; Nanto, Dwi
Science and Technology Indonesia Vol. 9 No. 4 (2024): October
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.2024.9.4.989-998

Abstract

Conventional epoxy coating for surface metal corrosion protection reported many unsolved technical problems. Adding filler in the epoxy could enhance the promising properties of the composite coating. Our work describes in detail the synthesizing and characterizing epoxy/carbon composite coating. Epoxy was mixed with thinner high gloss (HG) and hardener and stirred using a stirrer apparatus. After blending, various carbons were added (1 wt. %, 3 wt. %, and 5 wt. %) and then appropriately stirred. The different mixture composite was coated onto the steel plate cold rolled coiled (SPCC) plate using high-volume low-pressure (HVLP) in two passes. Various characterizations were performed, including crystallographic orientation, Infra-Red (IR)-spectra, surface morphology, thickness, hydrophobicity, hardness, and corrosion using X-ray diffraction (XRD), Fourier transform infrared (FTIR), Scanning electron microscopy (SEM), portable dry film coating thickness (DFT), digital camera, Vickers microhardness tester, and Potentiostat, respectively. More carbon micron-sized content led to elevate the peak intensity, surface bumpiness, and hydrophobicity. The uppermost external bumpiness and hydrophobicity values are 23.51 µm and 101◦. Hardness depends on carbon content and more carbon leads to an increase in the hardness of the composited coating. The highest average Vickers hardness value is 28.24 HV. The coating thickness influenced the corrosion rate, more coating thickness promoted lesser corrosion rate. The highest coating thickness (60.8 µm) promoted a corrosion rate of around 5.65×10−4 mmpy.
Probabilistic Multi-Item Inventory Model for Chemicals in Regional Drinking Water Company Dwipurwani, Oki; Puspita, Fitri Maya; Supadi, Siti Suzlin; Yuliza, Evi
Science and Technology Indonesia Vol. 9 No. 4 (2024): October
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.2024.9.4.1024-1032

Abstract

Inventory management of chemicals in The Regional Drinking Water Company (Perusahaan Daerah Air Minum, PDAM) is known to play an essential role in ensuring the smooth production of clean water and preventing shortages of chemicals that can affect production. At present, 2 primary models for multi-item inventory replenishment are under consideration by PDAM, namely individual and joint replenishment of items. Therefore, this study aims to evaluate the efficiency and effectiveness of individual and joint replenishment models based on uncertain demand with specific probability distribution. The results showed that a probabilistic inventory model (Q, r) with individual replenishment for chemicals in PDAM was recommended.

Page 40 of 56 | Total Record : 551

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