Pub Date : 2024-01-22DOI: 10.26554/sti.2024.9.1.113-119
I. Ilim, Laila Hidayah, Devi Yuliyanda, K. D. Pandiangan, W. Simanjuntak
This research was conducted to study preparation of nitrogen compounds by reacting palm oil derived methyl esters and diethanolamine using sodium methoxide as a catalyst. The chemical composition of the product was analyzed using the gas chromatography-mass spectrometry (GC-MS) method. The product was then applied as a corrosion inhibitor for mild steel in CO2 saturated 3% NaCl solution. Experimental results indicate that the reaction product contains six nitrogen compounds with a relative percentage of 63.7%, and the rest 36.7% are a mixture of unreacted diethanolamine and unreacted methyl esters. The results of the corrosion experiments show that the product obtained exhibited appreciably high performance as reflected by a percentage of protection (%P) of 96.85%. The performance of the product as a corrosion inhibitor is also supported by the SEM image of the mild steel sample, which shows that the surface of the sample is well protected. The results of this work demonstrate that nitrogen compounds obtained have promising potential as corrosion inhibitors, particularly to prevent corrosion by CO2 gas.
{"title":"Sodium Methoxide Catalyzed Preparation of Nitrogen Compounds from Palm Oil Methyl Esters as Corrosion Inhibitor","authors":"I. Ilim, Laila Hidayah, Devi Yuliyanda, K. D. Pandiangan, W. Simanjuntak","doi":"10.26554/sti.2024.9.1.113-119","DOIUrl":"https://doi.org/10.26554/sti.2024.9.1.113-119","url":null,"abstract":"This research was conducted to study preparation of nitrogen compounds by reacting palm oil derived methyl esters and diethanolamine using sodium methoxide as a catalyst. The chemical composition of the product was analyzed using the gas chromatography-mass spectrometry (GC-MS) method. The product was then applied as a corrosion inhibitor for mild steel in CO2 saturated 3% NaCl solution. Experimental results indicate that the reaction product contains six nitrogen compounds with a relative percentage of 63.7%, and the rest 36.7% are a mixture of unreacted diethanolamine and unreacted methyl esters. The results of the corrosion experiments show that the product obtained exhibited appreciably high performance as reflected by a percentage of protection (%P) of 96.85%. The performance of the product as a corrosion inhibitor is also supported by the SEM image of the mild steel sample, which shows that the surface of the sample is well protected. The results of this work demonstrate that nitrogen compounds obtained have promising potential as corrosion inhibitors, particularly to prevent corrosion by CO2 gas.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":"20 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139608140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-22DOI: 10.26554/sti.2024.9.1.189-197
Widiarti Widiarti, M. Usman, A. R. Putri, E. Russel
Data in the fields of finance, business, economics, agriculture, the environment and weather are commonly in the form of time series data. To analyze time series data that involves more than one variable (multivariate), vector autoregressive (VAR) models, vector autoregressive moving average (VARMA) models are generally used. If the variables discussed have cointegration, then the VAR model is modified into a vector error correction model (VECM). The relationship between short-term dynamics and deviation in the VECM model is assumed to be linear. If there is a nonlinear relationship between short-term dynamics and deviation, then a threshold vector error correction model (TVECM) can be used. The variables used in this research consist of oil production and Indonesian oil and gas production from January 2019 to March 2021. The research results show that the best model for data on oil production and oil and gas production is the TVECM 2 Regime model. Based on the TVECM 2 Regime model, further analysis, namely Granger causality and Impulse Response Function are discussed.
{"title":"Modeling and Analysis Data Production of Oil, and Oil and Gas in Indonesia by Using Threshold Vector Error Correction Model","authors":"Widiarti Widiarti, M. Usman, A. R. Putri, E. Russel","doi":"10.26554/sti.2024.9.1.189-197","DOIUrl":"https://doi.org/10.26554/sti.2024.9.1.189-197","url":null,"abstract":"Data in the fields of finance, business, economics, agriculture, the environment and weather are commonly in the form of time series data. To analyze time series data that involves more than one variable (multivariate), vector autoregressive (VAR) models, vector autoregressive moving average (VARMA) models are generally used. If the variables discussed have cointegration, then the VAR model is modified into a vector error correction model (VECM). The relationship between short-term dynamics and deviation in the VECM model is assumed to be linear. If there is a nonlinear relationship between short-term dynamics and deviation, then a threshold vector error correction model (TVECM) can be used. The variables used in this research consist of oil production and Indonesian oil and gas production from January 2019 to March 2021. The research results show that the best model for data on oil production and oil and gas production is the TVECM 2 Regime model. Based on the TVECM 2 Regime model, further analysis, namely Granger causality and Impulse Response Function are discussed.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":"18 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139609359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-22DOI: 10.26554/sti.2024.9.1.17-27
Rian Oktiansyah, H. Widjajanti, Arum Setiawan, E. Elfita
Peronema canescens, often known as sungkai, is widely used and can be found all around Indonesia. The public believes that the leaves may reduce fever and strengthen the immune system. However, the effectiveness of sungkai fruit has not been thoroughly investigated. In this research, we looked at endophytic fungus extracts from sungkai fruit’s that have antioxidant and antibacterial properties. The study’s results will serve as the foundation for further investigation into the development of potential natural chemicals with antioxidant and antibacterial properties. Morphologically, the endophytic fungi isolated from sungkai fruit were identified. The antioxidant and antibacterial properties of endophytic fungal extracts were studied using the DPPH technique and the paper disk diffusion method. By employing molecular identification and column chromatography to separate the active compounds, the most likely endophytic fungal isolates were found based on the results of the bioactivity tests. Using 1D NMR spectroscopic methods, the chemical’s structure was determined, and the results were compared to NMR data for the same compound published in the literature. Fruit of sungkai had 8 strains of endophytic fungus (RBH1-RBH8). Strong antibacterial and very strong antioxidant activity were shown by the RBH5 isolate (IC50 < 20 μg/mL). Pythium periplocum was determined to be the RBH5 isolate based on molecular testing. Pure chemical compound extracted from RBH5 isolates shown highly potent and potent antibacterial and antioxidant effects. The chemical compound was identified by spectroscopy as 3-hydroxy-4(hydroxy(4-hydroxyphenyl)methyl)-γ-butyrolactone. The results of this study serve as the foundation for developing compounds as pharmaceutical raw materials via further research phases.
{"title":"Antioxidant and Antibacterial Activity of Endophytic Fungi Isolated from Fruit of Sungkai (Peronema canescens)","authors":"Rian Oktiansyah, H. Widjajanti, Arum Setiawan, E. Elfita","doi":"10.26554/sti.2024.9.1.17-27","DOIUrl":"https://doi.org/10.26554/sti.2024.9.1.17-27","url":null,"abstract":"Peronema canescens, often known as sungkai, is widely used and can be found all around Indonesia. The public believes that the leaves may reduce fever and strengthen the immune system. However, the effectiveness of sungkai fruit has not been thoroughly investigated. In this research, we looked at endophytic fungus extracts from sungkai fruit’s that have antioxidant and antibacterial properties. The study’s results will serve as the foundation for further investigation into the development of potential natural chemicals with antioxidant and antibacterial properties. Morphologically, the endophytic fungi isolated from sungkai fruit were identified. The antioxidant and antibacterial properties of endophytic fungal extracts were studied using the DPPH technique and the paper disk diffusion method. By employing molecular identification and column chromatography to separate the active compounds, the most likely endophytic fungal isolates were found based on the results of the bioactivity tests. Using 1D NMR spectroscopic methods, the chemical’s structure was determined, and the results were compared to NMR data for the same compound published in the literature. Fruit of sungkai had 8 strains of endophytic fungus (RBH1-RBH8). Strong antibacterial and very strong antioxidant activity were shown by the RBH5 isolate (IC50 < 20 μg/mL). Pythium periplocum was determined to be the RBH5 isolate based on molecular testing. Pure chemical compound extracted from RBH5 isolates shown highly potent and potent antibacterial and antioxidant effects. The chemical compound was identified by spectroscopy as 3-hydroxy-4(hydroxy(4-hydroxyphenyl)methyl)-γ-butyrolactone. The results of this study serve as the foundation for developing compounds as pharmaceutical raw materials via further research phases.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":"59 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139606961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-22DOI: 10.26554/sti.2024.9.1.198-206
Latif Al Qadri, Gita Aldira Abelta, Melany Febrina, Abdul Rajak, Sena Maulana, M. A. Asagabaldan, Tarmizi Taher
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.
{"title":"Effect of Calcination Temperature on the Adsorption Performance of Tanggamus Natural Zeolite for Ammonium Removal from Shrimp Pond Wastewater","authors":"Latif Al Qadri, Gita Aldira Abelta, Melany Febrina, Abdul Rajak, Sena Maulana, M. A. Asagabaldan, Tarmizi Taher","doi":"10.26554/sti.2024.9.1.198-206","DOIUrl":"https://doi.org/10.26554/sti.2024.9.1.198-206","url":null,"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.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139607473","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-22DOI: 10.26554/sti.2024.9.1.1-6
Qaiyyum Hafizi Bin Hasnan
This study investigates the Multi-Criteria Decision Making (MCDM) topic to address the complexities of decision processes involving ambiguous information. We introduce the Triangular Fuzzy Geometric Bonferroni Mean (TFGBM) operator, a novel aggregation technique inspired by the Geometric Bonferroni Mean (GBM) concept. This operator is intended to aggregate triangular fuzzy numbers within MCDM problems effectively. We thoroughly investigate the properties of TFGBM and its distinct forms to ensure its practical utility. We introduce the Triangular Fuzzy Geometric Weighted Bonferroni Mean (TFGWBM) operator to accommodate situations where input factors have variable degrees of significance. Based on this foundation, we present a comprehensive framework for decision-making involving multiple attributes in ambiguous triangular fuzzy environments. A relevant case study regarding selecting an optimal location for a Halal center demonstrates the efficacy and applicability of our methodology. We emphasize the tangibility and efficiency of the suggested methodology in improving decision-making processes by emphasizing this real-world application.
{"title":"Revolutionizing Multi-Criteria Decision Making with the Triangular Fuzzy Geometry Bonferroni Mean Operator (TFGBM)","authors":"Qaiyyum Hafizi Bin Hasnan","doi":"10.26554/sti.2024.9.1.1-6","DOIUrl":"https://doi.org/10.26554/sti.2024.9.1.1-6","url":null,"abstract":"This study investigates the Multi-Criteria Decision Making (MCDM) topic to address the complexities of decision processes involving ambiguous information. We introduce the Triangular Fuzzy Geometric Bonferroni Mean (TFGBM) operator, a novel aggregation technique inspired by the Geometric Bonferroni Mean (GBM) concept. This operator is intended to aggregate triangular fuzzy numbers within MCDM problems effectively. We thoroughly investigate the properties of TFGBM and its distinct forms to ensure its practical utility. We introduce the Triangular Fuzzy Geometric Weighted Bonferroni Mean (TFGWBM) operator to accommodate situations where input factors have variable degrees of significance. Based on this foundation, we present a comprehensive framework for decision-making involving multiple attributes in ambiguous triangular fuzzy environments. A relevant case study regarding selecting an optimal location for a Halal center demonstrates the efficacy and applicability of our methodology. We emphasize the tangibility and efficiency of the suggested methodology in improving decision-making processes by emphasizing this real-world application.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":"31 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139607324","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-22DOI: 10.26554/sti.2024.9.1.129-136
Erni Salasia Fitri, R. Mohadi, N. Palapa, Susila Arita Rachman, A. Lesbani
Water is one of the most basic human needs, and dyes are one of the sources of water pollution. Since adsorption has proven to be effective in removing contaminants, it is the most widely used technique. In this adsorption, a LDH Zn-Al /magnetic biochar composite was used for dye removal. Zn-Al LDH, magnetic biochar, and LDH Zn-Al/biochar magnetic composite were successfully synthesized, based on XRD and FTIR studies. XRD analysis of the Zn-Al LDH material shows diffractions of (003), (006), (101), (012), (015), (107), and (110) around the 2theta angle at 10.29°, 20.07°, 29.59°, 32.12°, 34.02°, 48.06°, and 60.16° which are characteristic of LDH materials. In magnetic biochar and LDH Zn-Al/magnet biochar composites diffraction (220), (311), (422) and (440) at 2theta around 24.9°, 35°, 63° and 68.4° in these materials indicate the characteristics of carbon-based materials from biochar. FTIR analysis showed the appearance of a vibration peak at 1404cm−1 indicating the presence of C H groups contained in biochar. The characteristic double-layer hydroxy (M-O) vibrations below 1000 cm−1 also indicated that the composite preparation process had been successful. The study’s results show that cationic dyes are more easily adsorbed than anionic dyes. Specifically, the LDH Zn-Al/Magnetic Biochar composite more extensively absorbs the cationic dye malachite green.
{"title":"Selective Removal of Anionic and Cationic Dyes Using Magnetic Composites","authors":"Erni Salasia Fitri, R. Mohadi, N. Palapa, Susila Arita Rachman, A. Lesbani","doi":"10.26554/sti.2024.9.1.129-136","DOIUrl":"https://doi.org/10.26554/sti.2024.9.1.129-136","url":null,"abstract":"Water is one of the most basic human needs, and dyes are one of the sources of water pollution. Since adsorption has proven to be effective in removing contaminants, it is the most widely used technique. In this adsorption, a LDH Zn-Al /magnetic biochar composite was used for dye removal. Zn-Al LDH, magnetic biochar, and LDH Zn-Al/biochar magnetic composite were successfully synthesized, based on XRD and FTIR studies. XRD analysis of the Zn-Al LDH material shows diffractions of (003), (006), (101), (012), (015), (107), and (110) around the 2theta angle at 10.29°, 20.07°, 29.59°, 32.12°, 34.02°, 48.06°, and 60.16° which are characteristic of LDH materials. In magnetic biochar and LDH Zn-Al/magnet biochar composites diffraction (220), (311), (422) and (440) at 2theta around 24.9°, 35°, 63° and 68.4° in these materials indicate the characteristics of carbon-based materials from biochar. FTIR analysis showed the appearance of a vibration peak at 1404cm−1 indicating the presence of C H groups contained in biochar. The characteristic double-layer hydroxy (M-O) vibrations below 1000 cm−1 also indicated that the composite preparation process had been successful. The study’s results show that cationic dyes are more easily adsorbed than anionic dyes. Specifically, the LDH Zn-Al/Magnetic Biochar composite more extensively absorbs the cationic dye malachite green.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":"67 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139606535","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-22DOI: 10.26554/sti.2024.9.1.36-42
N. Khalefa
Heusler alloys were prepared in this study using the Arc-Melting method in which 30 g of the Arc-melting pure elements were combusted in an Argon arc furnace. Saturation magnetization, X-ray diffraction (XRD) analysis, and scanning electron microscope (SEM) were used to characterize the prepared alloys in terms of the compositions (Co2TiZ), where Z= Al, Ge, Sb are related IVB sub-group metals. In this work, the specimens containing Ge and Ti have fully Ferro magnetically order and L21 chemical structure with magnetism due to the magnetic moments attributed to the Co site. The Heusler alloys containing IIB or IVB sub-group metals such as Al, Ti, or Ge behave ferromagnetism, with the magnetic moments being attributed to the magnetic moments of the Co sites. Heusler alloys containing the group IVB element such as Sb exhibited vacant chemical effects with Co sites, and they also contain some paramagnetic compounds. Heusler alloys with Sb element exhibited paramagnetic behavior with vacant chemical order. Alloys demonstrate different magnetic properties as a result of temperature change and exchange interaction with atomic structure.
本研究采用弧熔法制备 Heusler 合金，即在氩弧炉中燃烧 30 克弧熔纯元素。饱和磁化、X 射线衍射 (XRD) 分析和扫描电子显微镜 (SEM) 被用来表征所制备合金的成分 (Co2TiZ)，其中 Z= Al、Ge、Sb 是相关的 IVB 亚族金属。在这项工作中，含有 Ge 和 Ti 的试样具有完全铁磁有序和 L21 化学结构，其磁性归因于 Co 位点的磁矩。含有 IIB 或 IVB 亚族金属（如 Al、Ti 或 Ge）的 Heusler 合金具有铁磁性，磁矩归因于 Co 位点的磁矩。含有 IVB 族元素（如锑）的 Heusler 合金表现出与 Co 位点的空位化学效应，它们还含有一些顺磁化合物。含有锑元素的 Heusler 合金表现出顺磁性，具有空位化学效应。由于温度变化和原子结构的交换相互作用，合金表现出不同的磁性能。
{"title":"A Study of the Magnetic Properties and Structure of Heusler Alloys Prepared by Arc-Melting Technique","authors":"N. Khalefa","doi":"10.26554/sti.2024.9.1.36-42","DOIUrl":"https://doi.org/10.26554/sti.2024.9.1.36-42","url":null,"abstract":"Heusler alloys were prepared in this study using the Arc-Melting method in which 30 g of the Arc-melting pure elements were combusted in an Argon arc furnace. Saturation magnetization, X-ray diffraction (XRD) analysis, and scanning electron microscope (SEM) were used to characterize the prepared alloys in terms of the compositions (Co2TiZ), where Z= Al, Ge, Sb are related IVB sub-group metals. In this work, the specimens containing Ge and Ti have fully Ferro magnetically order and L21 chemical structure with magnetism due to the magnetic moments attributed to the Co site. The Heusler alloys containing IIB or IVB sub-group metals such as Al, Ti, or Ge behave ferromagnetism, with the magnetic moments being attributed to the magnetic moments of the Co sites. Heusler alloys containing the group IVB element such as Sb exhibited vacant chemical effects with Co sites, and they also contain some paramagnetic compounds. Heusler alloys with Sb element exhibited paramagnetic behavior with vacant chemical order. Alloys demonstrate different magnetic properties as a result of temperature change and exchange interaction with atomic structure.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":"20 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139608146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-22DOI: 10.26554/sti.2024.9.1.59-68
Shinta Marito Siregar, S. Humaidi, N. Bukit, Erna Frida
This study explores the effects of incorporating palm oil fuel ash (POFA) and fly ash (FA) as partial cement substitutes on the mechanical properties and characteristics of high-quality mortar, specifically Engineered Cementitious Composites (ECC). ECC mortar was fabricated by milling POFA waste and FA through a top-down method utilizing a ball mill. The resulting material was subjected to tests for slump flow, water absorption, compressive strength, and characterized through XRF, FTIR, SEM/EDX, and XRD analyses. FTIR analysis verified the existence of Si-O and Al-O groups within the composite made of POFA-FA ECC. XRF analysis of FA and POFA showed cementitious properties, with SiO2+Al2O3+Fe2O3 exceeding 50% and CaO surpassing 10%. SEM and XRD results indicated minimal cavity formation, suggesting a high compressive strength in the mortar. Particle size distribution analysis revealed prevalent particles in the 1.5×10−1 to 2.0×10−1 μm range. The compressive strength test after 28 days, incorporating 15% FA and 10% POFA, yielded the highest strength at 59.30 MPa. The water absorption values ranged from 1.25% to 2.67%, indicating that POFA-FA assists in the cement hydration process and also serves as a filler. As a result, the material’s density is very high, leading to fewer voids formed, thus reducing the trapped water, which significantly affects the mortar’s strength.
{"title":"Palm Oil Fuel Ash and Fly Ash for a Partial Replacement of Cement in High-Quality, Environmentally Friendly Mortar as a Solution to Industrial Waste","authors":"Shinta Marito Siregar, S. Humaidi, N. Bukit, Erna Frida","doi":"10.26554/sti.2024.9.1.59-68","DOIUrl":"https://doi.org/10.26554/sti.2024.9.1.59-68","url":null,"abstract":"This study explores the effects of incorporating palm oil fuel ash (POFA) and fly ash (FA) as partial cement substitutes on the mechanical properties and characteristics of high-quality mortar, specifically Engineered Cementitious Composites (ECC). ECC mortar was fabricated by milling POFA waste and FA through a top-down method utilizing a ball mill. The resulting material was subjected to tests for slump flow, water absorption, compressive strength, and characterized through XRF, FTIR, SEM/EDX, and XRD analyses. FTIR analysis verified the existence of Si-O and Al-O groups within the composite made of POFA-FA ECC. XRF analysis of FA and POFA showed cementitious properties, with SiO2+Al2O3+Fe2O3 exceeding 50% and CaO surpassing 10%. SEM and XRD results indicated minimal cavity formation, suggesting a high compressive strength in the mortar. Particle size distribution analysis revealed prevalent particles in the 1.5×10−1 to 2.0×10−1 μm range. The compressive strength test after 28 days, incorporating 15% FA and 10% POFA, yielded the highest strength at 59.30 MPa. The water absorption values ranged from 1.25% to 2.67%, indicating that POFA-FA assists in the cement hydration process and also serves as a filler. As a result, the material’s density is very high, leading to fewer voids formed, thus reducing the trapped water, which significantly affects the mortar’s strength.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":"28 50","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139608214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-22DOI: 10.26554/sti.2024.9.1.207-214
H. A. Oramahi, Tirsa Maurisa, Nurhaida Nurhaida, H. Darwati, Slamet Rifanjani
This research utilized response surface methodology (RSM) to explore how the yield of liquid smoke obtained from ketapang wood (Terminalia catappa) is influenced by the size of wood particles and the temperature of pyrolysis. Gas chromatography-mass spectrometry (GC-MS) was used to characterize the liquid smoke. To assess liquid smoke’s antifungal effects, a petri dish bioassay was conducted using 1.0-4.0% (v/v) concentrations against Schizophyllum commune. RSM was applied to optimize vinegar from T. catappa by varying the wood particle size and the pyrolysis temperature. The optimal yield, 24.67%, was obtained with a 3.22 mm particle size and a 425°C pyrolysis temperature. The liquid smoke produced at 400-450°C completely inhibited of S. commune growth at 2.0-4.0%. The primary components of the liquid smoke at 400°C were 2-methoxy- phenol (24.85%), creosol (8.39%), 4-ethyl-2-methoxy- phenol (7.21%), 2-5-methyl-furancarboxaldehyde (4.55%), and 4-ethyl-2-methoxy-phenol (3.74%). The primary components at 425°C were 2-methoxy-phenol (25.60%), creosol (15.15%), 5-methyl-2 furancarboxaldehyde (12.75%), and 2,6-dimethoxy-phenol (9.31%). At 450°C, the main components were 2-methoxy-phenol (25.26%), 4-ethyl-2-methoxy-phenol (8.46%), creosol (8.40%), 5-methyl-2-furancarboxaldehyde (4.02%), and 4-ethyl-2-methoxy-phenol (3.98%).
{"title":"Optimization and Characterization of Liquid Smoke Produced by Terminalia catappa Wood Pyrolysis and its In Vitro Antifungal Activity","authors":"H. A. Oramahi, Tirsa Maurisa, Nurhaida Nurhaida, H. Darwati, Slamet Rifanjani","doi":"10.26554/sti.2024.9.1.207-214","DOIUrl":"https://doi.org/10.26554/sti.2024.9.1.207-214","url":null,"abstract":"This research utilized response surface methodology (RSM) to explore how the yield of liquid smoke obtained from ketapang wood (Terminalia catappa) is influenced by the size of wood particles and the temperature of pyrolysis. Gas chromatography-mass spectrometry (GC-MS) was used to characterize the liquid smoke. To assess liquid smoke’s antifungal effects, a petri dish bioassay was conducted using 1.0-4.0% (v/v) concentrations against Schizophyllum commune. RSM was applied to optimize vinegar from T. catappa by varying the wood particle size and the pyrolysis temperature. The optimal yield, 24.67%, was obtained with a 3.22 mm particle size and a 425°C pyrolysis temperature. The liquid smoke produced at 400-450°C completely inhibited of S. commune growth at 2.0-4.0%. The primary components of the liquid smoke at 400°C were 2-methoxy- phenol (24.85%), creosol (8.39%), 4-ethyl-2-methoxy- phenol (7.21%), 2-5-methyl-furancarboxaldehyde (4.55%), and 4-ethyl-2-methoxy-phenol (3.74%). The primary components at 425°C were 2-methoxy-phenol (25.60%), creosol (15.15%), 5-methyl-2 furancarboxaldehyde (12.75%), and 2,6-dimethoxy-phenol (9.31%). At 450°C, the main components were 2-methoxy-phenol (25.26%), 4-ethyl-2-methoxy-phenol (8.46%), creosol (8.40%), 5-methyl-2-furancarboxaldehyde (4.02%), and 4-ethyl-2-methoxy-phenol (3.98%).","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139607639","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-22DOI: 10.26554/sti.2024.9.1.148-155
I. Indrawati, F. Puspita, S. S. Supadi, E. Yuliza, Krisda Rizki
Good management of goods is needed so that the inventory activities of a business can run smoothly as the part of supply chain management which aims to monitor the flow of stock of goods from the purchasing process, and storage to the point of sale. In terms of inventory or supplies of pharmaceutical goods, conditions such as shortages or stockouts must also be considered which are a matter of control, management, and security. In this study, an inventory model is formulated with deterioration or damage to pharmaceutical goods that occurs due to the length of time when the goods are stored with a linear demand level. In the optimal solution, the inventory time occurs when it reaches the zero point (t1) of 0.34 and the cycle length (T1) of 0.83 with an average minimum total cost (TC) of $445.25 per cycle which is completed by WolframAlpha software. Sensitivity analysis changes the value results in the value of (TC) which that increases for all parameters. In increasing the linear function variables (a and b), it produces t1 and T1 stable values. An increase in the cost of each item damage (DC) and constant damage rate (theta) produces a t1 stable value, but the value of T1 increases. The increase in storage costs (h) results in a decrease in the value of t1 and T1. An increase in the cost of shortages (s) results in an increase in the value of t1 and a decrease in the value of T1.
{"title":"Inventory Model for Deteriorating Pharmaceutical Items with Linear Demand Rate","authors":"I. Indrawati, F. Puspita, S. S. Supadi, E. Yuliza, Krisda Rizki","doi":"10.26554/sti.2024.9.1.148-155","DOIUrl":"https://doi.org/10.26554/sti.2024.9.1.148-155","url":null,"abstract":"Good management of goods is needed so that the inventory activities of a business can run smoothly as the part of supply chain management which aims to monitor the flow of stock of goods from the purchasing process, and storage to the point of sale. In terms of inventory or supplies of pharmaceutical goods, conditions such as shortages or stockouts must also be considered which are a matter of control, management, and security. In this study, an inventory model is formulated with deterioration or damage to pharmaceutical goods that occurs due to the length of time when the goods are stored with a linear demand level. In the optimal solution, the inventory time occurs when it reaches the zero point (t1) of 0.34 and the cycle length (T1) of 0.83 with an average minimum total cost (TC) of $445.25 per cycle which is completed by WolframAlpha software. Sensitivity analysis changes the value results in the value of (TC) which that increases for all parameters. In increasing the linear function variables (a and b), it produces t1 and T1 stable values. An increase in the cost of each item damage (DC) and constant damage rate (theta) produces a t1 stable value, but the value of T1 increases. The increase in storage costs (h) results in a decrease in the value of t1 and T1. An increase in the cost of shortages (s) results in an increase in the value of t1 and a decrease in the value of T1.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":"296 12","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140499911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：