Science and Technology Indonesia最新文献_第2页

Improvement of Solubility Usnic Acid Loaded on Mesoporous Silica SBA-15 and Physicochemical Characterization 介孔二氧化硅 SBA-15 上负载的松萝酸溶解度的改善及理化特性分析

Science and Technology Indonesia Pub Date : 2024-04-02 DOI: 10.26554/sti.2024.9.2.251-259

L. Fitriani, Cindy Maynia Azzahra, Adhitya Jessica, Uswatul Hasanah, Erizal Zaini

{"title":"Improvement of Solubility Usnic Acid Loaded on Mesoporous Silica SBA-15 and Physicochemical Characterization","authors":"L. Fitriani, Cindy Maynia Azzahra, Adhitya Jessica, Uswatul Hasanah, Erizal Zaini","doi":"10.26554/sti.2024.9.2.251-259","DOIUrl":"https://doi.org/10.26554/sti.2024.9.2.251-259","url":null,"abstract":"Usnic acid, a secondary metabolite of lichen Usnea sp., has several pharmacological activities, but it is poorly soluble in water. This study aimed to improve the solubility and dissolution rate of usnic acid loaded in mesoporous silica SBA-15 at a mass ratio of 1:1. and evaluate its physical stability. Physicochemical characterization was carried out via the nitrogen adsorption desorption isotherm, differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectroscopy, and powder X-ray diffraction (PXRD). Usnic acid-loaded SBA-15 was stored at 40 °C with various relative humidities (RH) and then analyzed by PXRD for the physical stability. Usnic acid adsorbed well in the pores of SBA-15, as shown by a decrease in the volume pore and surface area of SBA-15 according to the nitrogen adsorption. Moreover, usnic acid-SBA-15 showed a decrease in the degree of crystallinity according to PXRD analysis and no melting point based on DSC analysis. The FTIR spectrum of usnic acid–SBA-15 corresponds to the spectra of each raw material. The solubility of usnic acid increased 5.15 times after adsorbed on SBA-15. The dissolution rate also showed a significant increase (p < 0.05) from 19.51% to 84.27%. Usnic acid–SBA-15 was relatively stable at RH 75%. Thus, the adsorption of usnic acid on SBA-15 can increase its solubility, dissolution rate, and physical stability.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":"29 32","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140753102","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

An Updated Water Masses Stratification of Indonesian Maritime Continent (IMC) Attributed to Normal and ENSO Conditions by Argo Float 利用阿尔戈浮标分析归因于正常和厄尔尼诺/南方涛动条件的印度尼西亚海洋大陆（IMC）最新水团分层情况

Science and Technology Indonesia Pub Date : 2024-04-02 DOI: 10.26554/sti.2024.9.2.299-313

A. Bahiyah, A. Wirasatriya, W. Mardiansyah, I. Iskandar

{"title":"An Updated Water Masses Stratification of Indonesian Maritime Continent (IMC) Attributed to Normal and ENSO Conditions by Argo Float","authors":"A. Bahiyah, A. Wirasatriya, W. Mardiansyah, I. Iskandar","doi":"10.26554/sti.2024.9.2.299-313","DOIUrl":"https://doi.org/10.26554/sti.2024.9.2.299-313","url":null,"abstract":"The tropical area of the Indonesian Maritime Continent (IMC) is frequently regulated by El Niño Southern Oscillation (ENSO), resulting in various water mass stratification in every climate event, such as El Niño and La Niña occurrences. As a consequence, changes in the typical Indonesian Throughflow (ITF) are linked to ENSO circumstances that affect the Indian Ocean. This study used Argo float data to evaluate the change in water mass stratification and vertical density profiles along the main pathway of ITF at each event. However, due to a scarcity of observation data, the comparison study of normal to ENSO occurrences has been limited in the ITF area. In typical circumstances throughout the year, the entrance channel (the western Pacific Ocean, the northern waters of Molucca Island, and the Halmahera Sea) had a higher saline value and cooler water masses than other ITF channels, with a range of roughly 33.5 - 35.5 PSU/13 - 22 ◦C, particularly during the Northwest (NW) Monsoon (December to February or DJF). Unlike the inlet, the Temperature-Salinity (T-S) diagram showed a declining value in both parameters (Celebes Sea, Makassar Strait, and Molucca Sea). Still, the outflow pathway in the Southeastern Tropical Indian Ocean (SETIO) showed a rising T-S diagram. During La Niña events, IMC water masses are often portrayed as fresher and warmer, while reverse circumstances are depicted in El Niño events with exclusion at SETIO station, indicating saltier and colder water masses than normal conditions. An extreme alteration with a large T-S range is mostly depicted in Makassar Strait from Southeast (SE) monsoon (September to November or SON) to NW monsoon, followed by the Banda Sea and then the Molucca Sea.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":"40 40","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140752314","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 PAN/PVDF Nanofiber Mats Loaded with Coconut Shell Activated Carbon and Silicon dioxide for Lithium-Ion Battery Anodes 制备负载椰壳活性炭和二氧化硅的 PAN/PVDF 纳米纤维垫，用于锂离子电池阳极

Science and Technology Indonesia Pub Date : 2024-04-02 DOI: 10.26554/sti.2024.9.2.427-447

M. R. Almafie, Rahma Dani, Riyanto Riyanto, L. Marlina, J. Jauhari, I. Sriyanti

{"title":"Preparation of PAN/PVDF Nanofiber Mats Loaded with Coconut Shell Activated Carbon and Silicon dioxide for Lithium-Ion Battery Anodes","authors":"M. R. Almafie, Rahma Dani, Riyanto Riyanto, L. Marlina, J. Jauhari, I. Sriyanti","doi":"10.26554/sti.2024.9.2.427-447","DOIUrl":"https://doi.org/10.26554/sti.2024.9.2.427-447","url":null,"abstract":"Utilizing carbon materials derived from natural biomass holds significant promise for battery applications, owing to their low cost, abundant availability, and environmentally sustainable characteristics. However, graphite anode materials do not meet the demands of efficient batteries. Coconut shell waste has the potential to be used as activated carbon in energy storage anodes. By adding silicon dioxide (SiO2) to maintain structural stability and electrochemical reaction kinetics, the advantages of CCS can be maximized. Polyacrylonitrile/polyvinylidene fluoride (PAN/PVDF) composite polymer was used as a matrix to embed CCS/SiO2 and synthesize nanofibers via electrospinning. The resulting nanofibers had diameters ranging from to 575–707 nm, with cross-linked, porous, and beadless characteristics. Mechanical properties were measured by single-fiber micro tensile tests. The young modulus, tensile strength, and toughness of each nanofiber were successfully maintained at 13.7 ± 0.4 MPa, 34.4 ± 0.1 MPa, and 982 ± 10 kJ/m3, respectively, because of the presence of a β-crystal growth layer that facilitated efficient stress transmission. The reduction-oxidation process response had a potential difference of less than 1.286 V in the first cycle, whereas for the third and fifth cycles, it was maintained below 3.416 V. The lithium-ion diffusion coefficient was below 4.73×1013 cm2/s. Using the anode directly, as in lithium-ion batteries, provided a high capacity of 382 mAh/g after 200 cycles. Good cycle stability, with over 98% retention of the initial capacitance after 200 charge/discharge cycles, underscores its potential for application in lithium-ion batteries.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":"11 13","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140754036","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

Utilization of Bengkalis Beach Sand Silica as Raw Material in the Synthesis of Zeolite 4A 在合成沸石 4A 的过程中利用本卡利斯海滩砂硅石作为原料

Science and Technology Indonesia Pub Date : 2024-04-02 DOI: 10.26554/sti.2024.9.2.244-250

Y. Azis, Ida Zahrina, Ahmad Fadli, Muhammad Asyaf Hazzamy

{"title":"Utilization of Bengkalis Beach Sand Silica as Raw Material in the Synthesis of Zeolite 4A","authors":"Y. Azis, Ida Zahrina, Ahmad Fadli, Muhammad Asyaf Hazzamy","doi":"10.26554/sti.2024.9.2.244-250","DOIUrl":"https://doi.org/10.26554/sti.2024.9.2.244-250","url":null,"abstract":"Zeolite 4A is a porous material that is widely used as an adsorbent, catalyst, membrane, ion exchanger, molecular sieve, etc. As a source of silica in the synthesis of zeolite 4A, silica from natural materials, biomass waste or chemicals has been used. In this research, silica extracted from Bengkalis beach sand (BBS) was used as raw material. The silica content in its oxide form, silicon oxide (SiO2) in BBS reaches 90%. The synthesis of zeolite 4A was carried out using a hydrothermal process, by varying the mole ratio of Si/Al from the reactant sodium silicate to sodium aluminate, namely 1.2:1; 1.4:1; 1.6:1 at reaction temperatures of 100, 110 and 120°C. Based on characterization using X-ray diffraction and an infrared spectrometer, the best conditions were obtained at a mole ratio reactant of 1.6, a reaction temperature of 100°C with a crystallinity percentage reaching 80.97%. Based on SEM-EDX analysis, the zeolite has an agglomerated morphology with a Si/Al ratio of around 1.09. The surface area, pore volume, and pore diameter of the synthesized zeolite were analyzed using a Brunauer-Emmet-Teller (BET) technique, respectively 81.844 m2/g, 0.039 cm3/g, and 3.07 nm.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":"99 ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140755862","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 KI/KIO3/Methoxide Kaolin Catalyst and Performance Test of Catalysis in Biodiesel Production KI/KIO3/Methoxide Kaolin 催化剂的制备及其在生物柴油生产中的催化性能测试

Science and Technology Indonesia Pub Date : 2024-04-02 DOI: 10.26554/sti.2024.9.2.359-370

L. Buchori, W. Widayat, N. Ngadi, H. Hadiyanto, Ndaru Okvitarini

{"title":"Preparation of KI/KIO3/Methoxide Kaolin Catalyst and Performance Test of Catalysis in Biodiesel Production","authors":"L. Buchori, W. Widayat, N. Ngadi, H. Hadiyanto, Ndaru Okvitarini","doi":"10.26554/sti.2024.9.2.359-370","DOIUrl":"https://doi.org/10.26554/sti.2024.9.2.359-370","url":null,"abstract":"Kaolin is a natural ingredient that is in abundance and has not been widely used. Kaolin is a source of silica (SiO2) and alumina (Al2O3) so that it can be used as a heterogeneous catalyst in biodiesel production. This research aims to examine the influence of using impregnated kaolin as a heterogeneous catalyst on production of biodiesel. Research methods include calcination of natural kaolin, impregnation of kaolin using KI, KIO3, and preparation of kaolin-methoxide in various concentrations, as well as biodiesel production using an impregnated kaolin catalyst. The catalyst was characterized using XRD and SEM. The catalyst was tested for basicity using the Hammet indicator method with acid-base titration. The biodiesel product obtained was analyzed using GCMS. The results of XRD analysis showed that 8% kaolin-methoxide catalyst had the highest crystallinity among the others. The crystallinity obtained was 87.84% with a composition of 15.79% SiO2 and 78.86% Al2O3. SEM image results also show a more visible crystal shape. The highest basicity of the catalyst obtained was 0.240 mmol. The highest biodiesel yield using 8% kaolin-methoxide catalyst is 99.48%.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":"95 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140755332","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

Assessment of Antioxidant Activity, Total Phenolic and Flavonoid Contents of Albizia saponaria L. Bark Extract 评估皂荚树皮提取物的抗氧化活性、总酚类和类黄酮含量

Science and Technology Indonesia Pub Date : 2024-04-02 DOI: 10.26554/sti.2024.9.2.494-501

L. Lukman, Noorma Rosita, Retno Widyowati

{"title":"Assessment of Antioxidant Activity, Total Phenolic and Flavonoid Contents of Albizia saponaria L. Bark Extract","authors":"L. Lukman, Noorma Rosita, Retno Widyowati","doi":"10.26554/sti.2024.9.2.494-501","DOIUrl":"https://doi.org/10.26554/sti.2024.9.2.494-501","url":null,"abstract":"Langir (Albizia saponaria L.), belonging to the family of the Fabaceae, is a medicinal endemic plant of South Sulawesi, Indonesia. The Albizia genus shows antioxidant, antibacterial, anthelmintic, antidandruff, and anti-inflammatory properties. In this study, total phenolic (TP) and total flavonoid (TF) extracts from the bark of A. saponaria were screened for robust antioxidant activity in order to identify potential sources of new compounds for use in pharmaceutical formulations in the future. TP and TF of the 96% ethanol extract and fractions (hexane, ethyl acetate, butanol, and water) were calculated by the Folin–Ciocalteu and aluminum chloride procedures, respectively. Furthermore, the antioxidant activity was determined by DPPH free radical scavenging method and ABTS assay. Generally, both extract and fractions showed significant radical scavenging activities. Ethyl acetate fraction exhibited more potent radical scavenging activity in the DPPH method (IC50 35.27 ± 2.85 µg/mL) and ABTS assay (IC50 60.04 ± 0.98 µg/mL), followed by 96% ethanol extract, and hexane, butanol, and water fractions. Furthermore, the highest TP (4.50 ± 0.01 mg/g GAE) and TF (3.55 ± 0.04 mg/g QE) were obtained from ethyl acetate fraction. There was a strong correlation between antioxidant activity with TP (DPPH, R2 = 0.6436; ABTS, R2 = 0.7676) and TF content (DPPH, R2 = 0.5533; ABTS, R2 = 0.5961). The extract’s antioxidant properties may be attributable to its higher phenolic and flavonoid content. In summary, the phenolic and flavonoid content of the ethyl acetate fraction indicates its potential utility as a source of antioxidants.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":"27 25","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140753208","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

ZnAl LDH-based Derivative Materials as Photocatalysts: Synthesis, Characterization, and Catalytic Performance in Tetracycline Degradation 作为光催化剂的 ZnAl LDH 基衍生材料：四环素降解过程中的合成、表征和催化性能

Science and Technology Indonesia Pub Date : 2024-04-02 DOI: 10.26554/sti.2024.9.2.457-469

Rohmatullaili Rohmatullaili, N. Ahmad, Desti Erviana, Zultriana Zultriana, Dila Savira, R. Mohadi, A. Lesbani

{"title":"ZnAl LDH-based Derivative Materials as Photocatalysts: Synthesis, Characterization, and Catalytic Performance in Tetracycline Degradation","authors":"Rohmatullaili Rohmatullaili, N. Ahmad, Desti Erviana, Zultriana Zultriana, Dila Savira, R. Mohadi, A. Lesbani","doi":"10.26554/sti.2024.9.2.457-469","DOIUrl":"https://doi.org/10.26554/sti.2024.9.2.457-469","url":null,"abstract":"Layered Double Hydroxide (LDH)-derived materials exhibited different characteristics from LDH precursors. The conversion of ZnAl LDH into its derivative material has been carried out to find the best catalyst for TC degradation. ZnAl (LDH)-based catalysts in this study have been effectively synthesized using coprecipitation, calcination, and restacking procedures. ZnAl Layered Double Oxide (LDO) is derived from the calcination of ZnAl LDH at 500°C. ZnAl LDH was also modified by adding Garcinia mangostana pericarp extract (GME). XRD, FT-IR, UV-DRS, and SEM-EDX were used to investigate the synthesized catalyst. ZnAl LDH exhibited the typical LDH FT-IR spectra, whereas ZnAl LDO showed metal oxide-like spectra, and the ZnAl-GME composite displayed the combination spectra of precursor material. The ZnAl LDH XRD diffraction pattern exhibited the attributes of a layered material, whereas the other three catalysts did not. Calcination destroyed the layered structure of ZnAl LDH, whereas the addition of GME to LDH and LDO generated a single-layered composite. The modified ZnAl-GME composite showed a decrease in both particle size and bandgap energy. At an ideal pH of 5, the synthesized catalyst was used in a batch system photodegradation of 5 mg/L Tetracycline (TC), employing solar light irradiation. ZnAl LDO holds the most significant catalytic activity and structural stability through the fifth regeneration cycle, degraded TC up to 100% in 90 minutes.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":"25 27","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140753291","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

Modification of Indonesian Kaolinite-Based Silica Coarse (SC) for RNA Extraction Method of SARS-CoV-2 改进印度尼西亚高岭土基粗硅（SC）用于 SARS-CoV-2 的 RNA 提取方法

Science and Technology Indonesia Pub Date : 2024-04-02 DOI: 10.26554/sti.2024.9.2.325-335

Marchia Marthalena Marintan, Fithriyah Sjatha, Dita Arifa Nurani, Y. Krisnandi, Sariman Sariman

{"title":"Modification of Indonesian Kaolinite-Based Silica Coarse (SC) for RNA Extraction Method of SARS-CoV-2","authors":"Marchia Marthalena Marintan, Fithriyah Sjatha, Dita Arifa Nurani, Y. Krisnandi, Sariman Sariman","doi":"10.26554/sti.2024.9.2.325-335","DOIUrl":"https://doi.org/10.26554/sti.2024.9.2.325-335","url":null,"abstract":"One of the strategies to overcome the COVID-19 disease is through rapid diagnostic tests using the Reverse-Transcriptase Polymerase Chain Reaction (RT-PCR) test. The RT-PCR test is a detection and quantification test of nucleic acids, initiated by the pre-analytical step of purification of the nucleic acids. Purification of nucleic acid requires silica-based materials as a solid phase-extraction matrix or column. Herein, Silica Coarse (SC) in the form of suspension and powder columns; was prepared from natural Indonesian Kaolinite as an alternative extraction column to binding RNA of SARS-CoV-2. The RNA binding and releasing ability in SC was enhanced with the support of chaotropic agents in the form of Na+ and Guanidium+ as charged balancing cations, embedded in the silicate layer inside the kaolinite framework. SC, which has been supported with Na+ and Guanidium+ respectively, then studied its physicochemical characteristics using FTIR spectroscopy, X-ray diffraction technique, scanning electron microscopy, and BET surface area and pore size measurement. This work shows that the modified SC suspension column could extract RNA of SARS-CoV-2 that amplified better in the RT PCR test than SC powder columns, with the initial Ct value of all the SARS-CoV-2 specimens in the range < 20.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":"45 30","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140751956","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

Synthesis, Corrosion Inhibition Efficiency in Acidic Media, and Quantum Chemical Studies of Some Hydrazine Derivatives 某些肼衍生物的合成、在酸性介质中的缓蚀效率以及量子化学研究

Science and Technology Indonesia Pub Date : 2024-01-22 DOI: 10.26554/sti.2024.9.1.137-147

Huda Saleh Abood, E. Q. Jasim, M. A. Muhammad-Ali

{"title":"Synthesis, Corrosion Inhibition Efficiency in Acidic Media, and Quantum Chemical Studies of Some Hydrazine Derivatives","authors":"Huda Saleh Abood, E. Q. Jasim, M. A. Muhammad-Ali","doi":"10.26554/sti.2024.9.1.137-147","DOIUrl":"https://doi.org/10.26554/sti.2024.9.1.137-147","url":null,"abstract":"In this work, four hydrazone Schiff base derivatives N-(2,4-Dinitro-phenyl)-N’-(1H-pyrrol-2-ylmethylene)-hydrazine (1a), N-Benzo [1,3] dioxol-5-ylmethylene-N’-(2,4-dinitro-phenyl)-hydrazine (1b), (E)-5-((2-(2,4-dinitrophenyl)hydrazono)methyl)-2-hydroxybenzoic acid (1c) and (E)-1-(2,4-dinitrophenyl)-2-(2-methoxybenzylidene)hydrazine (1d) were synthesized by reaction of four aldehydes namely pyrrole-2-carboxaldehyde, piperonal, 5-formylsalicylic acid, and o-vanillin with 2,4-dinitrophenyl hydrazine to produce the final compounds 1a, 1b, 1c, and 1d, respectively. These four compounds were investigated as corrosion inhibitors in aqueous mild acidic static solution. FTIR, HNMR, and elemental analysis were used to elucidate the chemical structure of the synthesized inhibitors. Using potential dynamic polarization measurements, these inhibitors’ efficiency in preventing C-steel corrosion in 1.00 M HCl was studied. The results of the experiments revealed that 1×10−3 M is the ideal concentration for 1a, 1b, 1c, and 1d, and that the corresponding inhibition efficiencies for these subunits were 80.70%, 91.30%, 91.34, and 88.80%, respectively. The best corrosion inhibitors were compounds 1b and 1c. Furthermore, studies suggested that these substances are mixed-type inhibitors and that the efficiency of the inhibition is strongly correlated with their quantity. Quantum paraments included Dipole moment, energy band gap (ΔE), value of energy of lowermost unoccupied molecular orbital (ELUMO), and energy of high most occupied molecular orbital (EHOMO) using Molecular Operating Environment MOE, Gaussian, and HyperChem software packages were determined which demonstrated strong agreement between algorithmic and practical findings.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":"96 14","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139606009","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

Preissmann Four-Point Methods for Solution of Simplified Saint-Venant Equations Applied to Flood Routing in Prismatic Open Channels 普赖斯曼四点法求解简化圣-韦南方程应用于棱柱形明渠的洪水路径

Science and Technology Indonesia Pub Date : 2024-01-22 DOI: 10.26554/sti.2024.9.1.183-188

B. A. Sulistyono, Suryo Widodo

{"title":"Preissmann Four-Point Methods for Solution of Simplified Saint-Venant Equations Applied to Flood Routing in Prismatic Open Channels","authors":"B. A. Sulistyono, Suryo Widodo","doi":"10.26554/sti.2024.9.1.183-188","DOIUrl":"https://doi.org/10.26554/sti.2024.9.1.183-188","url":null,"abstract":"This research goal to compare the flow properties in the rectangular and trapezoidal open channels by examining the influence of the channel side slope is depicted by simplified Saint Venant Equations. The solution of these equations has been completed numerically by using Preissmann four-point scheme. The model is simulated using the Matlab application to point out the flow properties. The proposed model is validated by the model without simplification which was selected from the literature. The validation outcomes indicate that in common, the simulation outcomes of the two models have a good agreement. The simulation results show that the greater the slope of the channel side, the greater the peak discharge and the greater the time shift. The analysis emphasizes how channel geometry influences flow behavior, indicating that trapezoidal channels, with inclined side slopes z, yield slightly higher peak discharges compared to rectangular ones. For z = 0, discharge of peak Q = 7.38 m3/s and t = 18 s. For z = 2, discharge of peak Q = 7.39 m3/s and t = 21 s. For z = 4, discharge of peak Q = 7.45 m3/s and t = 23 s. For z = 6, discharge of peak Q = 7.51 m3/s and t = 24 s.","PeriodicalId":21644,"journal":{"name":"Science and Technology Indonesia","volume":"5 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139607464","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