Garuda - Garba Rujukan Digital

All

Science and Technology Indonesia

JSTI
Website

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

14 15 16 17 18

Study the Impact of Laser Energy on Laser-Induced Copper Plasma Parameters By Spectroscopic Analysis Technique Ibrahim Karim Abbas
Science and Technology Indonesia Vol. 7 No. 4 (2022): October
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

In this paper, spectroscopic analysis (OES) for copper (Cu) plasma was achieved at atmospheric pressure. Q switched Nd: YAG pulsed laser with a fundamental wavelength (1064 nm), energy range (500-800) mJ, frequency (6 Hz), and laser pulses (10-30 pulses) was applied to induce copper plasma. Based on the spectroscopic analysis, plasma parameters like electron temperature (Te), electron density (ne), Debye length (λD), and plasma frequency (fp) have been calculated. The results demonstrated that the laser energy affects all plasma parameters, with an electron temperature (Te) range of (0.6820-0.8949) eV and electron number density (ne) range of (13.667-17.235)×1017 cm−3. Also, the image of the place of laser bombardment of copper (Cu) metal shows three diameters or circles, each circle bears a different color from the other. It can be described as a crater, and the interaction of the laser with copper metal is obvious by laser ablation, and here the effect of the increased energy of the laser appears during the spectroscopic diagnosis and the process of metal bombardment.

Improvement of Congo Red Photodegradation Performance Through Zn/Al-TiO2 and Zn/Al-ZnO Preparation Nova Yuliasari; Amri; Risfidian Mohadi; Elfita Elfita; Aldes Lesbani
Science and Technology Indonesia Vol. 7 No. 4 (2022): October
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Layered double hydroxide (LDH) is an anionic clay material known to be effective as a catalyst for the photodegradation of dye organic pollutants. Zn/Al LDH was synthesized by coprecipitation then impregnated with metal oxides and calcined at 300oC to form Zn/Al-TiO2 and Zn/Al-ZnO as photodegradation catalysts of congo red (CR). The characterization of the catalysts after preparation using SEM and UV-DRS while the catalyst that have been used in 5 regeneration cycles was characterized by XRD and FTIR. Photodegradation of CR was carried out by optimizing pH, catalyst weight, and time radiation. Zn/Al LDH which was modified into Zn/Al-TiO2 and ZnAl-ZnO had a better degradation percentage, rate constant, and stability than Zn/Al LDH pristine structure. Zn/Al LDH, Zn/Al TiO2 and Zn/Al-ZnO catalyzed CR photodegradation for 120 minutes with percent degradation 68.39%, 81.24% and 71.09%, respectively.

Investigation of the Physical Properties and Droplet Combustion Analysis of Biofuel from Mixed Vegetable Oil and Clove Oil Adhes Gamayel; Mohamad Zaenudin; M. N. Mohammed; Eddy Yusuf
Science and Technology Indonesia Vol. 7 No. 4 (2022): October
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

The study of vegetable oil used as fuel in conventional engines leads to problems like the low volatility and high viscosity. This research aims to evaluate the droplet combustion characteristics that correlated with the density, viscosity, and the flash point of the biofuel from mixed vegetable oil with clove oil. Biofuels used in research are Jatropha Oil (CJO), Kapok Oil (KSO), Coconut oil (CCO), and all biofuel mixed with clove oil in 5% basis volume. Fuel properties that tested both biofuel and fuel mixture using the ASTM method are density (ASTM D1298), viscosity (ASTM D445), The flash point (ASTM D93). The droplet combustion experiment used suspended droplets placed in the junction of the K-type thermocouple and the Ni-Cr wire (as the coil heater) to heat the droplet until the combustion occurred. The result indicates that adding 5% clove oil in biofuel creates higher density, the viscosity decreases until 10%, and the flash point decrease to 30%. Droplet combustion results that adding 5% clove oil creating a more complete combustion process in CCO than KSO and CJO. Higher viscosity in KSO and CJO leads to eugenol and terpene (clove oil compound) trapping in the fuel droplet. Due to eugenol and terpene having great volatility, they are evaporating rapidly leading to secondary atomization and micro-explosion phenomena.

Preparation and Characterization of a Eutectic Mixture of Fenofibric Acid and Nicotinic Acid and Evaluatuion of In Vivo Antihyperlipidemic Activity Deni Anggraini; Hulwa Salsabila; Salman Umar; Yufri Aldi; Erizal Zaini
Science and Technology Indonesia Vol. 7 No. 4 (2022): October
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Fenofibric Acid (FA) is classified under Biopharmaceutical Classification System (BCS) class II due to its poorly soluble in water and high permeability. The present study aimed to prepare the eutectic mixture of FA with nicotinic acid (NA) and characterize its solid state properties and in vitro dissolution rate, along with its in vivo antihyperlipidemic activity. Solvent drop grinding was the method chosen to prepare the eutectic mixture of FA and NA. Solid-state properties were evaluated using thermal analysis Differential Scanning Calorimetry (DSC), crystallographic analysis Powder X-Ray Diffraction (PXRD), FT-IR spectroscopic analysis, and Scanning Electron Microscopy (SEM). To examine in vivo antihyperlipidemic activity, 16 male Swiss Webster rats were injected with 1% hyperlipidemia-inducing solution, followed by the oral administration of 9.45 mg/kg FA and NA (equivalent to 9.45 mg/kg FA), after which the decrease in cholesterol levels was measured. Two-way ANOVA was used to evaluate the data, followed by Duncan’s multiple range test (95% confidence interval). The results proved that FA formed the eutectic mixture with NA at a molar ratio of 6:4. The eutectic mixture of FA-NA had a better solubility and in vitro dissolution rate compared to intact FA, which also led to notably improved antihyperlipidemic activity.

The Diameter and Maximum Link of the Minimum Routing Cost Spanning Tree Problem Reni Permata Sari; Wamiliana; Akmal Junaidi; Wiwin Susanty
Science and Technology Indonesia Vol. 7 No. 4 (2022): October
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

The minimum routing cost spanning tree (MRCST) is a spanning tree that minimizes the sum of pairwise distances between its vertices given a weighted graph. In this study, we use Campos Algorithm with slight modifications on the coefficient of spanning potential. Those algorithms were implemented on a random table problem data of complete graphs of order 10 to 100 in increments of 10. The goal is to find the diameter (the largest shortest path distance) and the maximum link (the maximum number of edges connecting two vertices) in the spanning tree solution of MRCST. The result shows that a slight modification of the spanning potential coefficients gives better solutions.

Variation of M2+ (Ni and Zn) in Cellulose-based M2+/Cr Composite Materials to Determine Adsorption and Regeneration Abilities on Phenol Removal Alfan Wijaya; Tarmizi Taher; Aldes Lesbani; Risfidian Mohadi
Science and Technology Indonesia Vol. 7 No. 4 (2022): October
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Cellulose-based Ni/Cr (Ni/Cr-C) and cellulose-based Zn/Cr (Zn/Cr-C) composite materials have been successfully carried out, which is indicated by the XRD, FTIR, and BET analysis. Layered double hydroxide Ni/Cr (Ni/Cr-LDH) increased surface area from 0.128 m2/g to 2.207 m2/g in Ni/Cr-C composites, and layered double hydroxide Zn/Cr (Zn/Cr-LDH) also increased surface area from 0.133 m2/g to 3.714 m2/g in Zn/Cr-C composites. The pHpzc of the material in this study is pH 5.94-8.43, while the optimum pH of all materials is pH 9. Ni/Cr-LDH experienced an increase in adsorption capacity after becoming a Ni/Cr-C composite, from 8.985 mg/g to 24.510 mg/g, and Zn/Cr-LDH experienced an increase in adsorption capacity from 13.263 mg/g to 30.960 mg/g in Zn/Cr-C. Zn/Cr-C composite material has a greater adsorption ability than Ni/Cr-C. Kinetic and isotherm model in this study followed by PSO kinetic with optimum contact time at 70 minutes and Freundlich isotherm. Ni/Cr-C and Zn/Cr-C composite materials can be used repeatedly in the regeneration process until the 4th cycle.

Hydrochar and Humic Acid as Template of ZnAl Layered Double Hydroxide for Adsorption of Phenol Muhammad Badaruddin; Nur Ahmad; Erni Salasia Fitri; Aldes Lesbani; Risfidian Mohadi
Science and Technology Indonesia Vol. 7 No. 4 (2022): October
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

The adsorbents potential ZnAl-LDH, ZnAl-Hydrochar, and ZnAl-Humic acid were prepared using the coprecipitation method. The adsorbents were characterization by XRD, FTIR, and BET analysis. XRD peaks of ZnAl-LDH at 10.29°, 20.07°, 29.59°, 32.12°, 34.02°, 48.06°, and 60.16°. The FTIR absorption peak was observed at 3400-3500 cm−1, 1600-1700 cm−1, 1381 cm−1, 1000 cm−1, 500-700 cm−1. All adsorbents exhibited N2 adsorption-desorption isotherms type IV classified as a mesoporous structure (pore size= 2-50 nm). The surface areas of composites were higher than LDH and following order: ZnAl-Hydrochar > ZnAl-Humic acid > ZnAl-LDH. The kinetic parameter showed the pseudo-second-order kinetics model. The maximum adsorption capacity of ZnAl-LDH, ZnAl-Hydrochar, and ZnAl-Humic acid were 48.077 mg/g, 90.090 mg/g, 94.340 mg/g, respectively; with Freundlich isotherm model. Reusability after 5 times of ZnAl-LDH, ZnAl-Hydrochar, and ZnAl-Humic acid in the range 49.81-0.890%, 95.92-9.84%, and 70.02-5.72%, respectively. The adsorbent can be used up to 3 times.

Study of Anthocyanin Extraction from Red Banana (Musa sapientum L. var Rubra) Waste and Characteristics of Light Effects Yessy Rosalina; Endang Warsiki; Anas Miftah Fauzi; Illah Sailah
Science and Technology Indonesia Vol. 7 No. 4 (2022): October
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Anthocyanins are compounds responsible for plants’ blue, purple, violet, magenta, red, and orange colours. Anthocyanins are found in tropical fruits. Generally, anthocyanins are found in the peel tissues of plants. The increasing interest in anthocyanins, especially in the field of food and health, supports the development of anthocyanin exploration research. One of the uses of anthocyanins that are widely developed today is the addition of anthocyanins as indicators in smart packaging. For application on the packaging, in addition to extraction techniques, it is also necessary to assess the characteristics of anthocyanins in the environment. This study aims to examine the anthocyanin potential of red banana waste and the effect of light on anthocyanin stability. The anthocyanins observed are the result of anthocyanin extraction from the red banana peel and bracts using the maceration method. The solvent used is water acidified with citric acid. The study results showed that the total anthocyanin content in red banana bracts extract was higher than in extract from red banana peel. A concentrated extract from the bracts of a red banana contains 114.26 μg/g FW of total anthocyanins. In comparison, the concentrated extract of red banana peel contains 110.27 μg/g FW of total anthocyanins. Identification of concentrated extracts of red banana peel and flower through FTIR test, maximum wavelength test with UV-Vis and discolouration test showed that the extract contains anthocyanin compounds. Irradiation with a 25-watt bulb lamp, UV lamp and sunlight on concentrated extracts of the red banana peel and bracts showed degraded anthocyanin content. The results of this study show that the peel and flower of red bananas have the potential to be developed as a source of anthocyanins.

Green Synthesis of Nickel Aluminum Layered Double Hydroxide using Chitosan as Template for Adsorption of Phenol Hasja Paluta Utami; Nur Ahmad; Zaqiya Artha Zahara; Aldes Lesbani; Risfidian Mohadi
Science and Technology Indonesia Vol. 7 No. 4 (2022): October
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

In present study, a modification of the NiAl LDH composite with chitosan was successful. Characterization was carried out using X-rays, The results obtained show that there is an angle of 2θ at 11.57°(003); 22.91°(006); 35.04°(012); 39.73°(015); and 61.9°(110). The FT-IR spectrum of the Chitosan@NiAl LDH at Wavenumber 3448, 1635, 1543, and 601 cm−1. The NiAl LDH and chitosan have a surface area of 3.288 m2/g and 8.558 m2/g, respectively. An increase in the surface area of the composite Chitosan@NiAl LDH 9.493 m2/g, all of adsorbents follow type IV isotherm based on the classification according to IUPAC. The optimum pH of the NiAl LDH at pH 3. The optimum pH for chitosan and chitosan@NiAl LDH material is at the optimum pH of 5. The kinetic and isotherm model in the adsorption process is pseudo-second-order and Freundlich model, respectively. The maximum adsorption capacity of NiAl LDH, chitosan, and chitosan@NiAl LDH is 25.445, 23.753, and 33.223 mg/g, respectively. The increase in regeneration cycles causes a decrease in the percentage of adsorbed; sequentially, the percentage adsorbed during the fifth regeneration reaches 3.545, 1.966, 4.309%, respectively.

Acute Toxicity Test of Jatropha curcas L. on Nile Tilapia Seeds (Oreochromis niloticus L.) Nurhidayanti Nurhidayanti
Science and Technology Indonesia Vol. 5 No. 1 (2020): January
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

ABSTRACT The study investigating acute toxicity test of Jatropha curcas L. on Nile tilapia seeds (Oreochromis niloticus L.), had been conducted in May 2017, in Balai Riset Perikanan dan Perairan Umum (BRPPU) Mariana, Banyuasin. This study was aimed to determine the concentration of Jatropha curcas seed powder needed to cause 50% death of Nile tilapia seeds (LT50). This acute toxicity test used biological test with exposure time of 96 hours. The concentrations of Jatropha curcas tested were 0 (control), 240, 288, 346, 415, 498, 597, and 716 ppm which were applied for 96 hours. Data were analyzed using Spearman-Karber method with SPSS. Result showed LC50 of 24 hours was 551,271 ppm, LC50 of 48 hours was 466,513 ppm, and LC50 of 96 hours was 393,892 ppm. Meanwhile, LT50 for 597 ppm of Jatropha curcas was 1285, 166 minutes, and LT50 for 761 ppm was 784,121 minutes. The higher the concentration of Jatropha curcas seeds given the fastest time needed to cause the death of Nile tilapia seeds, Jatropha curcas seeds had moderate toxicity. Keywords: Acute toxicity, Jatropha curcas L., Biological test, Oreochromis niloticus L

Page 16 of 56 | Total Record : 551

14 15 16 17 18

Filter by Year

2016 2026

Filter By Issues

All Issue Vol. 11 No. 1 (2026): January Vol. 10 No. 4 (2025): October Vol. 10 No. 3 (2025): July Vol. 10 No. 2 (2025): April Vol. 10 No. 1 (2025): January Vol. 9 No. 4 (2024): October Vol. 9 No. 3 (2024): July Vol. 9 No. 2 (2024): April Vol. 9 No. 1 (2024): January Vol. 8 No. 4 (2023): October Vol. 8 No. 3 (2023): July Vol. 8 No. 2 (2023): April Vol. 8 No. 1 (2023): January Vol. 7 No. 4 (2022): October Vol. 7 No. 3 (2022): July Vol. 7 No. 2 (2022): April Vol. 7 No. 1 (2022): January Vol. 6 No. 2 (2021): April 2021 Vol. 6 No. 4 (2021): October Vol. 6 No. 3 (2021): July Vol. 6 No. 1 (2021): January Vol. 5 No. 4 (2020): October Vol. 5 No. 3 (2020): July Vol. 5 No. 2 (2020): April Vol. 5 No. 1 (2020): January Vol. 4 No. 4 (2019): October Vol 4 No 3 (2019): July Vol. 4 No. 2 (2019): April Vol 4 No 2 (2019): April Vol. 4 No. 1 (2019): January Vol. 3 No. 4 (2018): October Vol. 3 No. 3 (2018): July Vol. 3 No. 2 (2018): April Vol. 3 No. 1 (2018): January Vol. 2 No. 4 (2017): October Vol. 2 No. 3 (2017): July Vol. 2 No. 2 (2017): April Vol. 2 No. 1 (2017): January Vol. 1 No. 1 (2016): October More Issue

Home Page

OAI Link

Editorial Team

Contact

Reviewer

Google Scholar

Contact Name
-

Contact Email
-

Phone
-

Journal Mail Official
-

Editorial Address
-

Location
Kab. ogan ilir,

Sumatera selatan

INDONESIA

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Home Page

OAI Link

Editorial Team

Contact

Reviewer

Google Scholar

Contact Name -

Contact Email -

Phone -

Journal Mail Official -

Editorial Address -

Location Kab. ogan ilir, Sumatera selatan INDONESIA

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Contact Name
-

Contact Email
-

Phone
-

Journal Mail Official
-

Editorial Address
-

Location
Kab. ogan ilir,

Sumatera selatan

INDONESIA