Science and Technology Indonesia最新文献_第8页

Science and Technology Indonesia Pub Date : 2023-07-06 DOI: 10.26554/sti.2023.8.3.361-366

Novianty Novianty, J. Edianta, Jorena Jorena, Khairul Saleh, A. Bama, E. Koriyanti, M. Ariani, I. Royani

{"title":"Synthesis of Fe(III)-IIPs (Ion Imprinted Polymers): Comparing Different Concentrations of HCl and HNO3 Solutions in the Fe(III) Polymer Extraction Process for Obtaining the Largest Cavities in Fe(III)-IIPs","authors":"Novianty Novianty, J. Edianta, Jorena Jorena, Khairul Saleh, A. Bama, E. Koriyanti, M. Ariani, I. Royani","doi":"10.26554/sti.2023.8.3.361-366","DOIUrl":"https://doi.org/10.26554/sti.2023.8.3.361-366","url":null,"abstract":"This study was conducted to synthesize Fe (III)-IIPs by free radical polymerization using the cooling-heating method. Cooling processat -5◦C for 1 hour, as well as heating at 75◦C, 80◦C, and 85◦C maintained for 3 hours, 2 hours and 1 hour, respectively. The Fe (III)-IIPs synthesis process involved Fe(NO3)3 with an average diameter of 18.23 nm, methacrylic acid (MAA), ethylene glycol dimethacrylate (EGDMA), benzoyl peroxide (BPO) and ethanol, each of which plays a role as an analyte, functional monomer, cross-linker, initiator, and porogen. The result of the polymerization process was a polymer containing ions namely Fe(III) polymer. The ions need to be removed by the extraction process to produce Fe(III)-IIPs, which act as absorbents. Furthermore, the extraction process is very influential in the process of losing ions and the formation of cavities or templates in the polymer body. The number of cavities formed tends to affect the ability of Fe(III)-IIPs to identify the target ion which has similar physical and chemical properties to the shape of the Fe(III)-IIPs cavity. The extraction process was carried out on Fe(III) polymer samples using HCl and HNO3 solutions with varying concentrations of 3 M and 6 M, respectively. The transmission percentage of FTIR analysis showed that for samples of Fe(III)-IIPs HCl 3 M and 6 M were 94.258% and 95.666%, while for Fe(III)-IIPs HNO3 3 M and 6 M were 92.735%, respectively. The largest percentage was shown in the 6 M HCl IIPs sample, which indicated that there were several ions lost from the polymer body after the extraction process. This is also reinforced by the results of the SEM analysis processed with Matlab, which showed 498 cavities with a distribution of voids on a scale of <100 nm, totaling 470.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44154783","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}

引用次数: 0

Optimization of Liquid Smoke Products Made from Rubberwood with Pyrolysis Method 橡胶木热解制液烟产品的优化研究

Science and Technology Indonesia Pub Date : 2023-07-06 DOI: 10.26554/sti.2023.8.3.353-360

B. D. Afrah, M. Riady, L. Cundari, Muhammad Andzar Rizan, Jihan Utami, Siti Istiani Pratiwi, M. Y. Pratama

引用次数: 0

Synthesis, Characterization, and Antibacterial Activity of Some Mesalazine Derivatives 美沙拉嗪衍生物的合成、表征及抗菌活性研究

Science and Technology Indonesia Pub Date : 2023-07-06 DOI: 10.26554/sti.2023.8.3.338-343

E. Q. Jasim

{"title":"Synthesis, Characterization, and Antibacterial Activity of Some Mesalazine Derivatives","authors":"E. Q. Jasim","doi":"10.26554/sti.2023.8.3.338-343","DOIUrl":"https://doi.org/10.26554/sti.2023.8.3.338-343","url":null,"abstract":"Mesalazine, often referred to as mesalamine or 5-aminosalicylic acid (5-ASA), and its derivatives are some of the first medications to be approved for treating digestive tract inflammations, including ulcerative colitis and mild to moderate Crohn’s disease. Sulfasalazine, discovered in 1938 for therapeutic use, was the first mesalazine derivative. High yields of four different mesalazine derivatives were synthesized, including two Schiff bases and two azo compounds. The present study involved the synthesis of Schiff bases through the reaction of mesalazine with pyrrole-2-carbaldehyde or indole-2-carbaldehyde, resulting in the formation of 5-(((1H-pyrrol-2-yl)methylene)amino)-2-hydroxybenzoic acid (1) or 5-(((1H-indol-2-yl)methylene)amino)-2hydroxybenzoic acid (2), respectively. The synthesis of azo compounds involved the coupling of mesalazine with sulfamethoxazole or pyridoxine, resulting in the formation of 5-amino-2-hydroxy-3-((4-(N-(5-methylisoxazol-3-yl)sulfamoyl)phenyl)diazenyl)benzoic acid (3) or 2-hydroxy-5-((5-hydroxy-3,4-bis(hydroxymethyl)-6-methylpyridin-2-yl)diazenyl)benzoic acid (4), respectively. The identification of the synthesized compounds was carried out using IR and 1H-NMR spectroscopy. Antibacterial assessment of the synthetic compounds was performed in vitro against gram-negative bacteria (such as Escherichia coli and Pseudomonas aeruginosa) and gram-positive bacteria (Staphylococcus aureus). The antibacterial activity studies demonstrated that against Escherichia coli and Staphylococcus aureus, the Schiff base compounds are more active than azo compounds. Compound 1 showed the highest activity, resulting in a 23 mm inhibition zone against E. coli at 1000 ug/ml. In contrast, the antibacterial activity of compound 2 was observed to be 25 mm against S. aureus at the same highest concentration.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46306307","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}

引用次数: 0

Preparation of Al2O3 /PVA Nanocomposite Thin Films by a Plasma Jet Method 等离子体喷射法制备Al2O3 /PVA纳米复合薄膜

Science and Technology Indonesia Pub Date : 2023-07-06 DOI: 10.26554/sti.2023.8.3.471-478

S. J. Kadhem

{"title":"Preparation of Al2O3 /PVA Nanocomposite Thin Films by a Plasma Jet Method","authors":"S. J. Kadhem","doi":"10.26554/sti.2023.8.3.471-478","DOIUrl":"https://doi.org/10.26554/sti.2023.8.3.471-478","url":null,"abstract":"Alumina thin films have significant applications in the areas of optoelectronics, optics, electrical insulators, sensors and tribology. The novel aspect of this work is that the homogeneous alumina thin films were prepared in several stages to generate a plasma jet. In this paper, aluminium nanoparticles suspended in vinyl alcohol were prepared using exploding wire plasma. TEM analysis was used to determine the size and shape of particles in aluminium and vinyl alcohol suspensions; the TEM images showed that the particle size is 17.2 nm. Aluminium/poly vinyl alcohol (Al/PVA) thin films were prepared using this suspension on quartz substrate by plasma jet technique at room temperature with an argon gas flow rate of 1 L/min. The Al/PVA thin films were thermally converted to alumina films, where they were annealed at different temperatures (700, 800, or 900°C). X-ray diffraction (XRD), atomic force microscopy (AFM), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR) techniques were used to characterise these thin films before and after annealing process. The diffraction patterns of the prepared thin films before subjecting them to the annealing process indicated the presence of peaks belonging to aluminium and PVA; however, the diffraction patterns and FTIR spectra obtained for these films after the annealing process showed peaks indicating the formation of alumina films of different phases. AFM and SEM investigations proved that the formed particles for all prepared films before and after the annealing process were similar in size and almost spherical; the diameter of the particles was on the order of a few nanometres. To control the properties of prepared thin films, the plasma which was used to produce thin films is diagnosed spectrophotometrically. The generated plasma was diagnosed using optical emission spectroscopy to estimate the electron temperature Te; the electron temperature was 1.925 eV.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49114970","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}

引用次数: 0

Dynamics of Extreme Rainfall and Its Impact on Forest and Land Fires in the Eastern Coast of Sumatra 苏门答腊岛东海岸极端降雨动态及其对森林和陆地火灾的影响

Science and Technology Indonesia Pub Date : 2023-07-06 DOI: 10.26554/sti.2023.8.3.403-413

H. Akhsan, Muhammad Irfan, Supari Supari, I. Iskandar

{"title":"Dynamics of Extreme Rainfall and Its Impact on Forest and Land Fires in the Eastern Coast of Sumatra","authors":"H. Akhsan, Muhammad Irfan, Supari Supari, I. Iskandar","doi":"10.26554/sti.2023.8.3.403-413","DOIUrl":"https://doi.org/10.26554/sti.2023.8.3.403-413","url":null,"abstract":"This article examines the extreme climate events on the Eastern Coast of Sumatra over four decades (1981-2019) based on the extreme rainfall index defined using the Expert Team on Climate Change Detection and Indices (ETCCDI). The indices used include Consecutive Dry Day (CDD and the total rainfall per year (PRCPTOT). Theses indices were calculated and are based on the daily observation data from eight quality-controlled weather stations. While overall trends in extreme rainfall indices are not significant, there is a noticeable trend towards drought, with CDD rising by 1.23 days per decade and PRCPTOT decreased by 3.16 mm/year. The correlation between the Dipole Mode Index (DMI) and extreme rainfall indices in the August-September-October-November (ASON) period was positive, with CDD increasing with the more positive DMI value. On the other hand, the PRCPTOT index showed a decrease as the DMI more positive. The ENSO index and CDD are positively correlated during the dry season, while ENSO index negatively correlates with PRCPTOT. The duration of CDD during El Niño/positive Indian Ocean Dipole (IOD) events in 1997, 2015, and 2019 had significant impact on the forest and land fires on the Eastern Coast of Sumatra. The results are useful for policymakers in preventing forest and land fires on the Eastern Coast of Sumatra.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47608405","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}

引用次数: 0

Analysis of Extreme Heat Land Surface Temperature at a Tropical City (1988-2022): A Study on the Variability of Hot Spot during El Niño Southern Oscillation (ENSO) 某热带城市地表极热温度1988-2022年分析——El Niño南方涛动(ENSO)期间热点变率的研究

Science and Technology Indonesia Pub Date : 2023-07-06 DOI: 10.26554/sti.2023.8.3.388-396

O. V. Eboy, Ricky Anak Kemarau

{"title":"Analysis of Extreme Heat Land Surface Temperature at a Tropical City (1988-2022): A Study on the Variability of Hot Spot during El Niño Southern Oscillation (ENSO)","authors":"O. V. Eboy, Ricky Anak Kemarau","doi":"10.26554/sti.2023.8.3.388-396","DOIUrl":"https://doi.org/10.26554/sti.2023.8.3.388-396","url":null,"abstract":"Weather and climate in Malaysia, situated in Southeast Asia, are influenced by El Niño Southern Oscillation (ENSO), monsoons, Madden Julian Oscillation (MJO), and Indian Ocean Dipole (IOD). Previous studies on ENSO’s impact on temperature lacked detailed spatial information due to limited meteorological stations and cost constraints. This study utilizes remote sensing techniques, employing Landsat satellite data and Oceanic Niño Index (ONI) data, to analyze the spatial pattern of extreme land surface temperature distribution during ENSO events. Preprocessing includes radiometric and atmospheric corrections before converting digital numbers to land surface temperature values. Results indicate increased hotspot areas (>30°C) during El Niño events, with respective hotspot areas of 89.32 km² and 97.8 km² in 2015 and 2016, and 61.23 km² and 59.73 km² during La Niña in August and October 2018. Heat concentration areas remained consistent during the 1998 El Niño (89.32 km²) and the 2011 La Niña (55.82 km²). These findings highlight ENSO’s influence on altering hotspot distribution patterns. The increased hotspot area during El Niño events (34-36 km²) led to a 20-30% surge in electricity consumption as residents and offices in Kuching City, Sarawak, sought temperature regulation. This spatial information aids the government in identifying affected areas and implementing suitable measures to mitigate the impact of El Niño events.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68995031","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}

引用次数: 0

Bismuth Silicate/Silica-Titania Synthesis from In Situ Decomposition of Oil Palm Leaves as Silica Source 以油棕叶为硅源原位分解合成硅酸铋/硅钛

Science and Technology Indonesia Pub Date : 2023-07-06 DOI: 10.26554/sti.2023.8.3.397-402

Salprima Yudha S, M. Adfa, Swadexi Istiqphara, Muhamad Alvin Reagen

{"title":"Bismuth Silicate/Silica-Titania Synthesis from In Situ Decomposition of Oil Palm Leaves as Silica Source","authors":"Salprima Yudha S, M. Adfa, Swadexi Istiqphara, Muhamad Alvin Reagen","doi":"10.26554/sti.2023.8.3.397-402","DOIUrl":"https://doi.org/10.26554/sti.2023.8.3.397-402","url":null,"abstract":"In this work, bismuth silicate-titania has been synthesized in two stages by utilizing bismuth oxynitrate as an elemental source of bismuth, oil palm leaves (OPL) as a source of silica and titanium tetraisopropoxide (TTIP) as source of titania (TiO2). In the first stage, bismuth silicate/silica (Bi4Si3O12/SiO2) was formed, which occurs due to the in-situ decomposition of palm leaves and reacts directly with the bismuth precursor at high temperatures (900oC). The reaction could possibly occur through a solid-state reaction mechanism between bismuth oxide and silica or through a more complex mechanism within the reaction mixture. The resulting product then reacts with TTIP, which is added and heated at the same temperature to form Bi4Si3O12/SiO2-TiO2 (bismuth silicate/silica-titania). Characterization of the as-prepared product using X-ray diffraction showed the dominance of bismuth silicate and small amount of titania (TiO2). As a result, TiO2 could not be detected in the diffractogram. Nevertheless, an analysis using energy-dispersive X-rays showed the presence of titanium elements in the resulting composite. The results of this study can be used to develop ternary metal oxides based on natural resources and agricultural wastes, such as oil palm leaves.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44364614","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}

引用次数: 0

Development and Validation GC/MS Method for Methamphetamine Analysis in Urine by Miniaturization QuEChERS 小型化QuEChERS分析尿中甲基苯丙胺的GC/MS方法的建立与验证

Science and Technology Indonesia Pub Date : 2023-07-06 DOI: 10.26554/sti.2023.8.3.451-460

Soraya Aulia, R. Primaharinastiti, D. Purwanto

{"title":"Development and Validation GC/MS Method for Methamphetamine Analysis in Urine by Miniaturization QuEChERS","authors":"Soraya Aulia, R. Primaharinastiti, D. Purwanto","doi":"10.26554/sti.2023.8.3.451-460","DOIUrl":"https://doi.org/10.26554/sti.2023.8.3.451-460","url":null,"abstract":"This paper explains the development of a quick and easy gas chromatography (GC) approach to identify methamphetamine in urine. This research used gas chromatography with mass spectroscopy and a capillary column TG-5SILMS (5% phenyl methyl siloxane, 30 m x 0.32 x 25 m). The carrier gas flow rate was set at 1.0 mL/minute, the temperature inlet and detector had been set at 300°C, and the oven temperature was programmed to initiate at 50°C and held for 1.5 minutes before being raised to 300°C at a rate 40°C/minute and held for 3 minutes. Sample pre-treatment by modification of the QuEChERS method includes using a relatively large amount of inorganic salt, extraction volume and extraction cycle. The optimal conditions for processing a 400 uL urine sample were 160 mg magnesium sulphate, 40 mg sodium chloride, and 400 uL acetonitrile for organic solvent. According to the validation test, the detection limit for methamphetamine was 0.36 ug/mL; the quantitation limit was 1.09 ug/mL, and the calibration curve followed the regression line. y=1.0489x-3.7914, coefficient (r) was 0.9973. The recovery of the analyte spiked into urine at 5, 7 and 9 ug/mL on average was 100.5±2.33% for intraday dan 93.3±7.21% for interday. The precision was excellent, with an average coefficient of variation of 2.31%. The procedure was applied to four urine samples from drug users and the first abuser (25.51 ug/mL), the second abuser (15.05 ug/mL), the third abuser (17.72 ug/mL) and the last abuser (3.08 ug/mL) were all satisfactorily quantitated.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49312086","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}

引用次数: 0

Activated Hydrochar Prepared from Longan Fruit (Dimocarpus longan Lour.) Peel via Hydrothermal Carbonization-NaOH Activation for Cationic Dyes Removal 水热碳化-氢氧化钠活化法从桂圆皮中制备活性炭用于阳离子染料去除

Science and Technology Indonesia Pub Date : 2023-07-06 DOI: 10.26554/sti.2023.8.3.461-470

N. Palapa, A. Wijaya, N. Ahmad, Amri Amri, R. Mohadi, A. Lesbani

{"title":"Activated Hydrochar Prepared from Longan Fruit (Dimocarpus longan Lour.) Peel via Hydrothermal Carbonization-NaOH Activation for Cationic Dyes Removal","authors":"N. Palapa, A. Wijaya, N. Ahmad, Amri Amri, R. Mohadi, A. Lesbani","doi":"10.26554/sti.2023.8.3.461-470","DOIUrl":"https://doi.org/10.26554/sti.2023.8.3.461-470","url":null,"abstract":"Hydrothermal carbonization is recognized as a method of processing biomass into carbon-rich products due to its energy-saving and environmental-friendly advantages. In this study, two types of hydrochar were prepared from Longan Fruit (Dimocarpus longan Lour.) Peel via hydrothermal carbonization at temperatures of 190°C and 250°C and activated using NaOH (HC-ACT 190 and HC-ACT 250) for removal of malachite green (MG) and rhodamine B (RhB) dyes. The maximum capacity for MG dye removal using HC-ACT 190 and HC-ACT 250 materials was 172.414 mg/g and 250 mg/g, while for RhB dye was 111.111 mg/g and 151.515 mg/g, respectively. The optimum pH was obtained at pH 6 for MG and pH 3 for RhB with adsorption equilibrium time occurring at 90 minutes. The kinetic study shows that the adsorption process follows pseudo-second-order kinetics, while the isotherm model was determined by the Langmuir isotherm model. Materials can be reused effectively for at least 3 cycles with an adsorption percentage of MG dye removal using HC-ACT 190 and HC-ACT 250 materials was 69.91% and 83.15% respectively, while for RhB dye was 35.79% and 55.6% respectively. The material is more selective on MG dye compared to RhB dye based on the selectivity test on the adsorption of the dye mixture.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49372273","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}

引用次数: 0

The Subclasses of Analytic Functions of Complex Order with Application of q-Derivative Operators 复阶解析函数的子类及其q-导数算子的应用

Science and Technology Indonesia Pub Date : 2023-07-06 DOI: 10.26554/sti.2023.8.3.436-442

A. Janteng, Desmond Lee Ching Yiing, Yongkui Lun, Jaludin Janteng, Lee See Keong, R. Omar, Andy Liew Pik Hern

引用次数: 0