This research presents the influence of lithium bromide (LiBr) on the electrical properties of alginate in bio-based polymer electrolytes (BBPEs) system. Bio-based alginate was prepared using the solution casting technique with various LiBr compositions. The ionic conductivity and electrical properties of the prepared BBPEs samples were studied using electrical impedance spectroscopy over a frequency range of 50 Hz–1 MHz. A maximum ionic conductivity of 7.46 × 10 −5 S cm 1 was obtained for a sample containing 15 wt. % lithium bromide-doped alginate BBPEs at ambient temperature (303 K). The electrical analysis revealed that the most conductive sample based on alginate-LiBr BBPEs has optimum dielectric constant and loss, which significantly increases as temperature increases. The dielectric properties show that all alginateLiBr BBPEs are in non-Debye behavior conditions, where no single relaxation occurs in the present system.
研究了溴化锂（LiBr）对生物基聚合物电解质（BBPE）体系中藻酸盐电性能的影响。采用溶液浇铸技术，用不同的溴化锂组成制备了生物基海藻酸盐。使用电阻抗谱在50 Hz–1 MHz的频率范围内研究了所制备的BBPE样品的离子电导率和电学性质。在环境温度（303 K）下，含有15wt.%溴化锂掺杂的藻酸盐BBPE的样品的最大离子电导率为7.46×10−5 S cm 1。电学分析表明，基于藻酸盐-溴化锂BBPE的最具导电性的样品具有最佳的介电常数和损耗，其随着温度的升高而显著增加。介电性质表明，所有的藻酸盐LiBr-BBPE都处于非德拜行为条件下，在该条件下，本系统中没有发生单次弛豫。
{"title":"Influence of Lithium Bromide on Electrical Properties in Bio-based Polymer Electrolytes","authors":"A. F. Fuzlin, B. Sahraoui, A. S. Samsudin","doi":"10.7454/mst.v24i3.3836","DOIUrl":"https://doi.org/10.7454/mst.v24i3.3836","url":null,"abstract":"This research presents the influence of lithium bromide (LiBr) on the electrical properties of alginate in bio-based polymer electrolytes (BBPEs) system. Bio-based alginate was prepared using the solution casting technique with various LiBr compositions. The ionic conductivity and electrical properties of the prepared BBPEs samples were studied using electrical impedance spectroscopy over a frequency range of 50 Hz–1 MHz. A maximum ionic conductivity of 7.46 × 10 −5 S cm 1 was obtained for a sample containing 15 wt. % lithium bromide-doped alginate BBPEs at ambient temperature (303 K). The electrical analysis revealed that the most conductive sample based on alginate-LiBr BBPEs has optimum dielectric constant and loss, which significantly increases as temperature increases. The dielectric properties show that all alginateLiBr BBPEs are in non-Debye behavior conditions, where no single relaxation occurs in the present system.","PeriodicalId":42980,"journal":{"name":"Makara Journal of Technology","volume":"1 1","pages":""},"PeriodicalIF":0.2,"publicationDate":"2020-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41317795","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}
Tannaz Akbari Kolagar, S. Mohebbi, F. Ashrafi, Shahrzad Shoraka, H. A. Aghdaei, M. Zali
Hepatitis B virus (HBV) infection is one of the main causes of liver damage, which can also lead to chronic hepatitis B (CHB) infection. More than 240 million individuals worldwide are chronic carriers of HBV. Among individuals with CHB who are untreated, approximately 15% – 40% will progress to liver cirrhosis or cancer. The interactions between HBV and host immune response play significant roles in the progression of CHB. CHB can be generally divided into four different clinical phases: immune tolerance (IT), immune clearance, inactive carrier, and Hepatitis B surface antigen (HBsAg)negative reactivation phase (ENEG). Many studies showed that interleukins play important roles in anti-viral immunity and pathogenesis of chronic hepatitis. However, the relations between clinical phases of CHB and host immune transcriptome remain unclear. In this study, we aimed to investigate the expression of interleukin-17A (IL-17A) and IL17F genes in the peripheral blood mononuclear cells (PBMCs) of patients with CHB through different clinical stages. Results were compared with the control group, which comprised individuals with no history of pre-existing medical conditions. This case–control study was carried out on 32 patients with CHB as the case group and 32 healthy individuals as the control group. According to clinical data, CHB cases were divided into two groups: active (n = 22) and inactive (n = 11). PBMC samples were obtained from all groups. After total RNA extraction and cDNA synthesis, real-time PCR was used to determine IL-17A and IL-17F expression levels. The results were analyzed by REST software, SPSS, and GraphPad Prism. The IL-17A and IL-17F gene expression levels were observed to be significantly higher in the CHB group than in the control group (IL-17A: P = 0.0013; IL-17F: P = 0.0103). The active phase group (including IT, clearance, and reactivation samples) significantly increased in comparison with the inactive phase (IL-17A: P = 0.000; IL17F: P = 0.000). The study suggests that IL-17A and IL-17F do not only activate inflammation but are also involved in HBV-related disease progression and chronicity. Thus, mRNA levels of IL-17A and IL-17F could be used as a biomarker to diagnose CHB infection and distinguish between the active CHB phase from the inactive phase.
{"title":"Evaluation of IL-17A and IL-17F Gene Expression in Peripheral Blood Mononuclear Cells in Different Clinical Stages of Chronic Hepatitis B Infection in an Iranian Population","authors":"Tannaz Akbari Kolagar, S. Mohebbi, F. Ashrafi, Shahrzad Shoraka, H. A. Aghdaei, M. Zali","doi":"10.7454/mst.v24i2.3788","DOIUrl":"https://doi.org/10.7454/mst.v24i2.3788","url":null,"abstract":"Hepatitis B virus (HBV) infection is one of the main causes of liver damage, which can also lead to chronic hepatitis B (CHB) infection. More than 240 million individuals worldwide are chronic carriers of HBV. Among individuals with CHB who are untreated, approximately 15% – 40% will progress to liver cirrhosis or cancer. The interactions between HBV and host immune response play significant roles in the progression of CHB. CHB can be generally divided into four different clinical phases: immune tolerance (IT), immune clearance, inactive carrier, and Hepatitis B surface antigen (HBsAg)negative reactivation phase (ENEG). Many studies showed that interleukins play important roles in anti-viral immunity and pathogenesis of chronic hepatitis. However, the relations between clinical phases of CHB and host immune transcriptome remain unclear. In this study, we aimed to investigate the expression of interleukin-17A (IL-17A) and IL17F genes in the peripheral blood mononuclear cells (PBMCs) of patients with CHB through different clinical stages. Results were compared with the control group, which comprised individuals with no history of pre-existing medical conditions. This case–control study was carried out on 32 patients with CHB as the case group and 32 healthy individuals as the control group. According to clinical data, CHB cases were divided into two groups: active (n = 22) and inactive (n = 11). PBMC samples were obtained from all groups. After total RNA extraction and cDNA synthesis, real-time PCR was used to determine IL-17A and IL-17F expression levels. The results were analyzed by REST software, SPSS, and GraphPad Prism. The IL-17A and IL-17F gene expression levels were observed to be significantly higher in the CHB group than in the control group (IL-17A: P = 0.0013; IL-17F: P = 0.0103). The active phase group (including IT, clearance, and reactivation samples) significantly increased in comparison with the inactive phase (IL-17A: P = 0.000; IL17F: P = 0.000). The study suggests that IL-17A and IL-17F do not only activate inflammation but are also involved in HBV-related disease progression and chronicity. Thus, mRNA levels of IL-17A and IL-17F could be used as a biomarker to diagnose CHB infection and distinguish between the active CHB phase from the inactive phase.","PeriodicalId":42980,"journal":{"name":"Makara Journal of Technology","volume":" ","pages":""},"PeriodicalIF":0.2,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45511731","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}
In this study, we synthesized epoxidised monoethanolamide (EMA) from Bauhinia monandra seed oil (BMO) via a simple reaction route. In this process, BMO was transesterified to obtain a mixture of methyl esters, which was subjected to a urea adduct complexation reaction. The unsaturated methyl esters (BME) from the urea adduct complexation reaction were then epoxidised using performic acid produced in situ in a one-pot reaction system. The epoxidised methyl esters were converted to EMA by reacting them with monoethanolamine (1:10). The progression of the reaction was monitored using Fourier transform infrared spectroscopy and proton nuclear magnetic resonance spectroscopy, and the fatty acid composition was determined by gas chromatography. The results indicate that the most abundant fatty acid in BMO is C18:1 (25.70% ± 0.20%), with a degree of unsaturation of 49.00% ± 0.50%. After the urea adduct complexation reaction, the degree of unsaturation increased to 95.20% ± 0.10% with C18:2 (75.00% ± 0.10%) becoming the most dominant fatty acid. The oxirane oxygen content was found to be 5.50% ± 0.50%. The results of this study suggest that the urea adduct complexation reaction offers a potential means for increasing the unsaturation of fatty methyl esters. In addition, our findings show that EMA can be produced at low or room temperature.
{"title":"Synthesis of Epoxy Monoethanolamide from Bauhinia monandra Seed Oil","authors":"A. Adewuyi, R. Oderinde","doi":"10.7454/MST.V24I1.3851","DOIUrl":"https://doi.org/10.7454/MST.V24I1.3851","url":null,"abstract":"In this study, we synthesized epoxidised monoethanolamide (EMA) from Bauhinia monandra seed oil (BMO) via a simple reaction route. In this process, BMO was transesterified to obtain a mixture of methyl esters, which was subjected to a urea adduct complexation reaction. The unsaturated methyl esters (BME) from the urea adduct complexation reaction were then epoxidised using performic acid produced in situ in a one-pot reaction system. The epoxidised methyl esters were converted to EMA by reacting them with monoethanolamine (1:10). The progression of the reaction was monitored using Fourier transform infrared spectroscopy and proton nuclear magnetic resonance spectroscopy, and the fatty acid composition was determined by gas chromatography. The results indicate that the most abundant fatty acid in BMO is C18:1 (25.70% ± 0.20%), with a degree of unsaturation of 49.00% ± 0.50%. After the urea adduct complexation reaction, the degree of unsaturation increased to 95.20% ± 0.10% with C18:2 (75.00% ± 0.10%) becoming the most dominant fatty acid. The oxirane oxygen content was found to be 5.50% ± 0.50%. The results of this study suggest that the urea adduct complexation reaction offers a potential means for increasing the unsaturation of fatty methyl esters. In addition, our findings show that EMA can be produced at low or room temperature.","PeriodicalId":42980,"journal":{"name":"Makara Journal of Technology","volume":"1 1","pages":""},"PeriodicalIF":0.2,"publicationDate":"2020-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71343125","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}
Eriko Ishizu, Sari Honda, T. Ohta, B. Vongsak, S. Kumazawa
Propolis is a natural resin produced by honey bees from certain plants, has gained popularity as a food and alternative medicine. However, to the best of our knowledge, few studies on native Thailand stingless bee propolis are available. Information on the chemical composition and biological activities of propolis is needed to investigate its potential utility. Recently we have reported the possible plant origin of Thailand stingless bee propolis, Garcinia mangostana. In this study, further component analysis, functional evaluation, and identification of the plant origin of Thailand stingless bee propolis are conducted. Nine xanthones, including α-mangostin, garcinone C, γ-mangostin, cochinchinone T, βmangostin, gartanin, 8-deoxygartanin, 9-hydroxycalabaxanthone, and mangostanol, were identified from the propolis. Comparative analysis of 70% ethanol extracts of Thailand stingless bee propolis (EEP) and the yellow resin from the fruit surface of G. mangostana (EEM) was performed using LC-MS, and similar chromatographic patterns were obtained. This result suggests that the plant origin of Thailand stingless bee propolis is confirmed to be the yellow resin from the fruit surface of G. mangostana. EEP and EEM were then tested for their ability to inhibit the tube formation of human umbilical vein endothelial cells, and both samples inhibited the tube formation of these cells in a concentrationdependent manner. This result indicates that Thailand stingless bee propolis may have future applications in the prevention and treatment of angiogenesis-related diseases.
{"title":"Component Analysis and Antiangiogenic Activity of Thailand Stingless Bee Propolis","authors":"Eriko Ishizu, Sari Honda, T. Ohta, B. Vongsak, S. Kumazawa","doi":"10.7454/mst.v23i2.3703","DOIUrl":"https://doi.org/10.7454/mst.v23i2.3703","url":null,"abstract":"Propolis is a natural resin produced by honey bees from certain plants, has gained popularity as a food and alternative medicine. However, to the best of our knowledge, few studies on native Thailand stingless bee propolis are available. Information on the chemical composition and biological activities of propolis is needed to investigate its potential utility. Recently we have reported the possible plant origin of Thailand stingless bee propolis, Garcinia mangostana. In this study, further component analysis, functional evaluation, and identification of the plant origin of Thailand stingless bee propolis are conducted. Nine xanthones, including α-mangostin, garcinone C, γ-mangostin, cochinchinone T, βmangostin, gartanin, 8-deoxygartanin, 9-hydroxycalabaxanthone, and mangostanol, were identified from the propolis. Comparative analysis of 70% ethanol extracts of Thailand stingless bee propolis (EEP) and the yellow resin from the fruit surface of G. mangostana (EEM) was performed using LC-MS, and similar chromatographic patterns were obtained. This result suggests that the plant origin of Thailand stingless bee propolis is confirmed to be the yellow resin from the fruit surface of G. mangostana. EEP and EEM were then tested for their ability to inhibit the tube formation of human umbilical vein endothelial cells, and both samples inhibited the tube formation of these cells in a concentrationdependent manner. This result indicates that Thailand stingless bee propolis may have future applications in the prevention and treatment of angiogenesis-related diseases.","PeriodicalId":42980,"journal":{"name":"Makara Journal of Technology","volume":" ","pages":""},"PeriodicalIF":0.2,"publicationDate":"2019-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45879785","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}
Basic Local Alignment Sequencing Tool (BLAST) is a bioinformatics tool used for analyzing nucleotide sequences with regards to their similarity. BLAST can be found online on biological databases such as the National Center for Biotechnology Information (NCBI) and other such repositories. The mechanism of BLAST allows the target sequence to be compared with other sequences to find regions of local similarity, and thus, a comparability quotient that determines the resemblance between the sequences is created. Due to the open-platform nature of the online databanks, several sequences can be accepted with little to no interjections regarding the quality of sequence submitted. An example of unclean nucleotide sequences can be based on the number of non-template nucleotides, denoted as “N,” present within the sequence. Here we develop a self-established nucleotide sequence reading program known as “DNAChecker,” which helps identify the quality of the target sequence and therefore proposes the effectiveness of the BLAST result. DNAChecker is an inbuilt, program that runs on Python 3.4 and was implemented in the United States Agency for International Development (USAID) project conducted in Indonesia International Institute for Life Sciences. Although DNAChecker has proven to be useful, it has a lot of room for improvements, such as having a more objectively accurate means of differentiating between good and bad sequences.
{"title":"Use of the “DNAChecker” Algorithm for Improving Bioinformatics Research","authors":"Nausheen Bhat, Ezra B. Wijaya, A. A. Parikesit","doi":"10.7454/mst.v23i2.3488","DOIUrl":"https://doi.org/10.7454/mst.v23i2.3488","url":null,"abstract":"Basic Local Alignment Sequencing Tool (BLAST) is a bioinformatics tool used for analyzing nucleotide sequences with regards to their similarity. BLAST can be found online on biological databases such as the National Center for Biotechnology Information (NCBI) and other such repositories. The mechanism of BLAST allows the target sequence to be compared with other sequences to find regions of local similarity, and thus, a comparability quotient that determines the resemblance between the sequences is created. Due to the open-platform nature of the online databanks, several sequences can be accepted with little to no interjections regarding the quality of sequence submitted. An example of unclean nucleotide sequences can be based on the number of non-template nucleotides, denoted as “N,” present within the sequence. Here we develop a self-established nucleotide sequence reading program known as “DNAChecker,” which helps identify the quality of the target sequence and therefore proposes the effectiveness of the BLAST result. DNAChecker is an inbuilt, program that runs on Python 3.4 and was implemented in the United States Agency for International Development (USAID) project conducted in Indonesia International Institute for Life Sciences. Although DNAChecker has proven to be useful, it has a lot of room for improvements, such as having a more objectively accurate means of differentiating between good and bad sequences.","PeriodicalId":42980,"journal":{"name":"Makara Journal of Technology","volume":"76 ","pages":""},"PeriodicalIF":0.2,"publicationDate":"2019-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41285756","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}
Unfired brick is considered as a more environmentally friendly material than fired brick. It has lower mechanical properties than that of fired brick where humidity influences both bricks. Physical and mechanical properties of unfired bricks made of three kinds of mixtures were studied experimentally under three humidity conditions. The first kind of unfired brick was made only with soil and water while the second type was made of a mixture of soil, water and lime, and the third type was a mixture of soil, water, lime and uniform treated coir where 4% of lime mass was substituted with coir mass. Physical properties evaluation consisted of water content, absorption, volume shrinkage and density of those unfired bricks. Some variations occur in the third type of unfired bricks physical test results, where in general in more humid conditions there are tendency to have higher density, higher absorption, higher water content and less volume shrinkage compared to two other types of unfired bricks. Mechanical properties are evaluated by its modulus of rupture, compressive strength and modulus of elasticity. It is found that the addition of 4% treated 2.5 cm coir gives better mechanical properties in humid conditions compared to others types of unfired bricks.
{"title":"Experimental Evaluation of Three Different Humidity Conditions to Physical and Mechanical Properties of Three Different Mixtures of Unfired Soil Bricks","authors":"H. Purnomo, Srikandi Wahyu Arini","doi":"10.7454/mst.v23i2.3583","DOIUrl":"https://doi.org/10.7454/mst.v23i2.3583","url":null,"abstract":"Unfired brick is considered as a more environmentally friendly material than fired brick. It has lower mechanical properties than that of fired brick where humidity influences both bricks. Physical and mechanical properties of unfired bricks made of three kinds of mixtures were studied experimentally under three humidity conditions. The first kind of unfired brick was made only with soil and water while the second type was made of a mixture of soil, water and lime, and the third type was a mixture of soil, water, lime and uniform treated coir where 4% of lime mass was substituted with coir mass. Physical properties evaluation consisted of water content, absorption, volume shrinkage and density of those unfired bricks. Some variations occur in the third type of unfired bricks physical test results, where in general in more humid conditions there are tendency to have higher density, higher absorption, higher water content and less volume shrinkage compared to two other types of unfired bricks. Mechanical properties are evaluated by its modulus of rupture, compressive strength and modulus of elasticity. It is found that the addition of 4% treated 2.5 cm coir gives better mechanical properties in humid conditions compared to others types of unfired bricks.","PeriodicalId":42980,"journal":{"name":"Makara Journal of Technology","volume":" ","pages":""},"PeriodicalIF":0.2,"publicationDate":"2019-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45052196","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}
A photovoltaic (PV) mechanism consists of three important steps, i.e., (i) electron excitation upon absorption of photon with energy higher than the bandgap of fluorophore, (ii) excited-state electron injection from the fluorophore to the photoelectrode, and (iii) electron regeneration from the electrolyte to the fluorophore. An efficient electron regeneration could be achieved upon fulfillment of the requirements of energy alignment, i.e., lowest unoccupied molecular orb ital of fluorophore (LUMOfluorophore) > redox potential of electrolyte > highest occupied molecu lar orbital of fluorophore (HOMO fluorophore). This study investigated the electron regeneration efficiency of excitonic solar cells fabricated using three polymer-based electrolytes, i.e., (i) 60% carboxymethyl cellulose (CMC) blended with 40% polyvinyl alcohol (PVA), (ii) alginate, and (iii) xanthan. The redox potentials of the electro lytes (Eo ) were calculated using quantum chemical calculat ions under the framework of density functional theory. The compatibility of fluorophore and electrolyte was analyzed in terms of the energy level alignment. The cells fabricated using the three polymer-based electrolytes were analyzed, with the CMC/PVA-based cell yielding the highest efficiency, η, of 1.39% under the illumination of the sun. The low η of the cells can be attributed to the incompatible Eo of the electrolytes, which exh ibited a higher energy level than the LUMOfluorophore. The alginateand xanthan-based cells exh ibited inferior PV propert ies (i.e., open circuit voltage, short circuit current, fill factor, and η) to that of the CMC/PVA-based cell. This finding can be attributed to the increment of energy offset between Eo and HOMO fluorophore.
{"title":"A Study of the Electron Regeneration Efficiency of Solar Cells Fabricated Using CMC/PVA-, Alginate-, and Xanthan-based Electrolytes","authors":"Nur Farha Shaafi, Saifful K Muzakir, B. Sahraoui","doi":"10.7454/mst.v23i2.3634","DOIUrl":"https://doi.org/10.7454/mst.v23i2.3634","url":null,"abstract":"A photovoltaic (PV) mechanism consists of three important steps, i.e., (i) electron excitation upon absorption of photon with energy higher than the bandgap of fluorophore, (ii) excited-state electron injection from the fluorophore to the photoelectrode, and (iii) electron regeneration from the electrolyte to the fluorophore. An efficient electron regeneration could be achieved upon fulfillment of the requirements of energy alignment, i.e., lowest unoccupied molecular orb ital of fluorophore (LUMOfluorophore) > redox potential of electrolyte > highest occupied molecu lar orbital of fluorophore (HOMO fluorophore). This study investigated the electron regeneration efficiency of excitonic solar cells fabricated using three polymer-based electrolytes, i.e., (i) 60% carboxymethyl cellulose (CMC) blended with 40% polyvinyl alcohol (PVA), (ii) alginate, and (iii) xanthan. The redox potentials of the electro lytes (Eo ) were calculated using quantum chemical calculat ions under the framework of density functional theory. The compatibility of fluorophore and electrolyte was analyzed in terms of the energy level alignment. The cells fabricated using the three polymer-based electrolytes were analyzed, with the CMC/PVA-based cell yielding the highest efficiency, η, of 1.39% under the illumination of the sun. The low η of the cells can be attributed to the incompatible Eo of the electrolytes, which exh ibited a higher energy level than the LUMOfluorophore. The alginateand xanthan-based cells exh ibited inferior PV propert ies (i.e., open circuit voltage, short circuit current, fill factor, and η) to that of the CMC/PVA-based cell. This finding can be attributed to the increment of energy offset between Eo and HOMO fluorophore.","PeriodicalId":42980,"journal":{"name":"Makara Journal of Technology","volume":" ","pages":""},"PeriodicalIF":0.2,"publicationDate":"2019-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46154064","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}
The paper deals with the modelling of seismo-electromagnetics disturbance on the crustal earth by use of threedimensional (3D) finite-difference time-domain (FDTD) method. The model is built up by discretizing the frontier geographical region between Java Island and Sumatra Island in a cylindrical coordinate system-based 3D object. The proposed method is applied to compute and analyze electromagnetics (EM) fields of the observed very low frequency (VLF) wave used for the investigation. Boundary condition of uniaxial perfectly matched layer (UPML) are applied surrounding the area of computation for truncating the object of simulation. The investigation are focused on the propagation time of observed VLF wave and its amplitude variation between the observation point and disturbance pulse. The result shows that the propagation time is significantly affected by the distance of observation point and the permittivity of propagation medium. Meanwhile, the addition pulse associated with the earthquake influences the amplitude of observed VLF wave instead of its frequency.
{"title":"3D FDTD Method for Modeling of Seismo-Electromagnetics Disturbance on Crustal Earth","authors":"N. Shabrina, Y. Hobara, A. Munir","doi":"10.7454/mst.v23i2.3715","DOIUrl":"https://doi.org/10.7454/mst.v23i2.3715","url":null,"abstract":"The paper deals with the modelling of seismo-electromagnetics disturbance on the crustal earth by use of threedimensional (3D) finite-difference time-domain (FDTD) method. The model is built up by discretizing the frontier geographical region between Java Island and Sumatra Island in a cylindrical coordinate system-based 3D object. The proposed method is applied to compute and analyze electromagnetics (EM) fields of the observed very low frequency (VLF) wave used for the investigation. Boundary condition of uniaxial perfectly matched layer (UPML) are applied surrounding the area of computation for truncating the object of simulation. The investigation are focused on the propagation time of observed VLF wave and its amplitude variation between the observation point and disturbance pulse. The result shows that the propagation time is significantly affected by the distance of observation point and the permittivity of propagation medium. Meanwhile, the addition pulse associated with the earthquake influences the amplitude of observed VLF wave instead of its frequency.","PeriodicalId":42980,"journal":{"name":"Makara Journal of Technology","volume":" ","pages":""},"PeriodicalIF":0.2,"publicationDate":"2019-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41528882","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}
M. Yusoff, J. Idris, N. Zainal, M. F. Ibrahim, S. Abd-Aziz
Adsorption processes are widely used for the removal of heavy metals from waste streams. Oil palm decanter cake (OPDC) is used as a bioadsorbent because of its compositional properties for activated carbon production; moreover, it is a readily available raw material produced in palm o il mills and is thus abundant and cheap. In this study, the OPDC was carbonized at 700 °C and activated using steam at 700 °C to produce oil palm decanter cake activated carbon (ACOPDC). Batch adsorption experiments were carried out to compare the adsorption capacities of the raw OPDC and the AC-OPDC for heavy metals removal. The maximum adsorption capacities of AC-OPDC on Cu(II), Pb(II), and Zn(II) were found to be 45.01, 128.51, and 39.21 mg/g, respectively, which were higher than those of the raw OPDC. This study demonstrates that the AC-OPDC has the potential to be a bioadsorbent for heavy metal removal from wastewater.
{"title":"Adsorption of Heavy Metal Ions by Oil Palm Decanter Cake Activated Carbon","authors":"M. Yusoff, J. Idris, N. Zainal, M. F. Ibrahim, S. Abd-Aziz","doi":"10.7454/mst.v23i2.3760","DOIUrl":"https://doi.org/10.7454/mst.v23i2.3760","url":null,"abstract":"Adsorption processes are widely used for the removal of heavy metals from waste streams. Oil palm decanter cake (OPDC) is used as a bioadsorbent because of its compositional properties for activated carbon production; moreover, it is a readily available raw material produced in palm o il mills and is thus abundant and cheap. In this study, the OPDC was carbonized at 700 °C and activated using steam at 700 °C to produce oil palm decanter cake activated carbon (ACOPDC). Batch adsorption experiments were carried out to compare the adsorption capacities of the raw OPDC and the AC-OPDC for heavy metals removal. The maximum adsorption capacities of AC-OPDC on Cu(II), Pb(II), and Zn(II) were found to be 45.01, 128.51, and 39.21 mg/g, respectively, which were higher than those of the raw OPDC. This study demonstrates that the AC-OPDC has the potential to be a bioadsorbent for heavy metal removal from wastewater.","PeriodicalId":42980,"journal":{"name":"Makara Journal of Technology","volume":" ","pages":""},"PeriodicalIF":0.2,"publicationDate":"2019-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41791178","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}
Soheil Malekpour Kolbadinejad, V. Malekpour Ravasjan, A. Darvish
This article reports the general residential satisfaction, affecting ecological factors, and their importance in area in Tehran. The collected field data was analyzed using SPSS. Cronbach's alpha variable was used to determine the reliability of the questionnaire and the Friedman test was used to assess priorities that influence residential satisfaction. The results show that the quality of residential environments and general satisfaction of their residents may be enhanced by identifying these criteria and making appropriate plans for their improvement.
{"title":"Study of Ecological Design of Residential Complexes Using SPSS to Elevate Resident Satisfaction","authors":"Soheil Malekpour Kolbadinejad, V. Malekpour Ravasjan, A. Darvish","doi":"10.7454/mst.v23i2.3670","DOIUrl":"https://doi.org/10.7454/mst.v23i2.3670","url":null,"abstract":"This article reports the general residential satisfaction, affecting ecological factors, and their importance in area in Tehran. The collected field data was analyzed using SPSS. Cronbach's alpha variable was used to determine the reliability of the questionnaire and the Friedman test was used to assess priorities that influence residential satisfaction. The results show that the quality of residential environments and general satisfaction of their residents may be enhanced by identifying these criteria and making appropriate plans for their improvement.","PeriodicalId":42980,"journal":{"name":"Makara Journal of Technology","volume":" ","pages":""},"PeriodicalIF":0.2,"publicationDate":"2019-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49011905","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}
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