This research has found a new approach to improving the conductivity of bacterial cellulose BC/Pp... more This research has found a new approach to improving the conductivity of bacterial cellulose BC/Ppy bio composite films prepared using pulling. A wet BC pellicle is immersed in a liquid Ppy semiconductor for 30 minutes. The wet films was pulled out using a tensile testing machine. The results show that, after pulling, the conductivity of the films became better parallel to the sample drawing direction. Compared to the non-pulled out film, the pulled out film had higher conductivity (σ = 19.2 x 10-3 S/cm), increasing by 153%. The conductivity of films can still improve significantly because deformation during sample preparation in wet conditions.
Over the past three decades, chemical and biological water contamination has become a major conce... more Over the past three decades, chemical and biological water contamination has become a major concern, particularly in the industrialized world. Heavy metals, aromatic compounds, and dyes are among the harmful substances that contribute to water pollution, which jeopardies the human health. For this reason, it is of the utmost importance to locate methods for the cleanup of wastewater that are not genuinely effective. Owing to its non-toxicity, biodegradability, and biocompatibility, starch is a naturally occurring polysaccharide that scientists are looking into as a possible environmentally friendly material for sustainable water remediation. Starch could exhibit significant adsorption capabilities towards pollutants with the substitution of amide, amino, carboxyl, and other functional groups for hydroxyl groups. Starch derivatives may effectively remove contaminants such as oil, organic solvents, pesticides, heavy metals, dyes, and pharmaceutical pollutants by employing adsorption t...
Nanocellulose: from biosources to nanofiber and their applications
Physical Sciences Reviews
Nanocellulose is a product of cellulose, a sustainable and plentiful resource. It’s distinctive n... more Nanocellulose is a product of cellulose, a sustainable and plentiful resource. It’s distinctive nanoscale structure makes it a versatile, green and interesting material for a variety of applications. This article describes in detail the biosources of nanocellulose, the types and characteristics of nanocellulose, and the techniques used to produce nanocellulose fibers. The mechanical properties and morphologies of nanocellulose fibers are addressed in depth, along with their prospective applications in sectors, including paper packaging, building materials, composites, biomedicine, energy storage and filtration. In addition, the current state of nanocellulose research, including the opportunities in the field, as well as the future prospects of nanocellulose as a viable and sustainable material for a vast array of applications, are discussed.
Developing a conductive cellulose film without any metal compounds remains challenging, though in... more Developing a conductive cellulose film without any metal compounds remains challenging, though in great demand. However, cellulose film prepared from bacterial cellulose (BC) powder without any metal compounds has poor tensile, physical, and electrical properties, thus limiting its application. Herein, this study aims to prepare and characterize an all-cellulose film from 2,2,6,6-Tetramethylpiperidin-1-yl)oxyl (TEMPO)-oxidized bacterial cellulose (TOBC) powders without adding metal compounds and treated by ultrasonication. TOBC powders are sonicated with various powers of 250, 500, and 750 W for 20 min without any other substance. It was proved that increasing the ultrasonication power level resulted in a significant improvement in the properties of the film. The ultrasonication of 750 W increased tensile strength by 85%, toughness by 308%, light transmittance by 542%, and electrical conductivity by 174% compared to the nonsonicated film. A light-emitting diode connected to a power ...
This study examined the effect of sonication on FTIR and stability at various temperatures in wat... more This study examined the effect of sonication on FTIR and stability at various temperatures in water-based lubricants with a mixture of Carboxymethyl Cellulose (1wt%) and Uncaria Gambir extract (1wt% and 2wt%). The sample was prepared by mixing the two materials into distilled water using a magnetic stirrer and sonicator with time variations of 5 and 10 minutes. Before mixing, the Uncaria Gambir extract solution with water is first centrifuged to remove the dregs in the Uncaria Gambir extract powder. Stability was carried out in an open room (28oC), drying oven (50oC), and refrigerator (5oC). The stability test results showed that the mixture of Carboxymethyl Cellulose and Uncaria Gambir had good stability at all temperatures after sonication for a short duration. The longer sonication duration could fuse the fibrils of Carboxymethyl Cellulose, leading to increasing particle size. FTIR results also show that there is no chemical reaction that occurs. After adding the gambier, there w...
There is an increasing demand for food packaging materials that are safe for the environment and ... more There is an increasing demand for food packaging materials that are safe for the environment and human health. Pure polyvinyl alcohol (PVA) film is non-toxic and transparent but has poor UV-light shielding, thermal and moisture resistance, and antibacterial activity. Our previous work prepared and characterized a biofilm derived from PVA and edible Uncaria gambir extract (UG). The film has antibacterial properties and is anti-UV and flexible. However, UG is hydrophilic, making this film have low moisture absorption. To improve these properties, we trialed adding boric acid (BA) and UG into the PVA. This present study aims to characterize pure PVA film and blend films resulting from mixing PVA (10%), BA (0.5%), and UG (1%). It was found that the PVA/UG/BA film presented the best performance in terms of UV light absorption, tensile properties, thermal and moisture resistance, and antibacterial activity. This blend sample absorbs about 98% of the UV light at 400 nm wavelength without s...
Dragon fruit root fiber used as a reinforcement in the biocomposites film of cassava starch. The ... more Dragon fruit root fiber used as a reinforcement in the biocomposites film of cassava starch. The production method of biocomposites film was solution casting. The cassava starch serves as the matrix in the biocomposites film. The variation of amount fiber in matrix was 2, 4 and 6% from dry starch weight basis. Isolation of dragon fruit root fiber used alkalization and bleaching process with NaOH, NaClO2 and CH3COOH, respectively. Glycerol was used as plasticizers. Mechanical properties of biocomposites was determined by tensile test. The result shows that, tensile strength increased 200% after the addition of 6% fiber compared to pure starch film. Tensile test data was supported by X-Ray Difraction (XRD). Keywords: Biocomposite, Cassava Starch, Dragon fruit root fiber, Mechanical properties, XRD
There has been much effort to provide eco-friendly and biodegradable materials for the next gener... more There has been much effort to provide eco-friendly and biodegradable materials for the next generation of composite products owing to global environmental concerns and increased awareness of renewable green resources. This review article uniquely highlights the use of green composites from natural fiber, particularly with regard to the development and characterization of chitosan, natural-fiber-reinforced chitosan biopolymer, chitosan blends, and chitosan nanocomposites. Natural fiber composites have a number of advantages such as durability, low cost, low weight, high specific strength, non-abrasiveness, equitably good mechanical properties, environmental friendliness, and biodegradability. Findings revealed that chitosan is a natural fiber that falls to the animal fiber category. As it has a biomaterial form, chitosan can be presented as hydrogels, sponges, film, and porous membrane. There are different processing methods in the preparation of chitosan composites such as solution ...
Polylactic acid (PLA) is a thermoplastic polymer produced from lactic acid that has been chiefly ... more Polylactic acid (PLA) is a thermoplastic polymer produced from lactic acid that has been chiefly utilized in biodegradable material and as a composite matrix material. PLA is a prominent biomaterial that is widely used to replace traditional petrochemical-based polymers in various applications owing environmental concerns. Green composites have gained greater attention as ecological consciousness has grown since they have the potential to be more appealing than conventional petroleum-based composites, which are toxic and nonbiodegradable. PLA-based composites with natural fiber have been extensively utilized in a variety of applications, from packaging to medicine, due to their biodegradable, recyclable, high mechanical strength, low toxicity, good barrier properties, friendly processing, and excellent characteristics. A summary of natural fibers, green composites, and PLA, along with their respective properties, classification, functionality, and different processing methods, are d...
The raw data PD measurement results by using a computer usually contain noise that can lead to mi... more The raw data PD measurement results by using a computer usually contain noise that can lead to miss interpretation. So as to obtain an accurate diagnosis, then this noise must be separated from the raw data. In this study, the electrodes used were needle-plane electrode and the samples tested are polymer films placed on the electrode plane and the air gap is located between the needle and polymer films. There are two types of arrangement of the electrodes, the first electrode needle wrapped with the film and the second polymer are not wrapped with polymer films. To separate the data PD of raw-data is necessary algorithms that can automatically select the threshold value of the standard deviation value. To obtain the optimum value, the threshold value selected based on the standard deviation of each value segment. The results show that this method has been used to distinguish between the electrode pattern PD wrapped or not wrapped polymer.
Penelitian ini bertujuan untuk mengetahui pengaruh chemical treatment menggunakan NaOH pada ser... more Penelitian ini bertujuan untuk mengetahui pengaruh chemical treatment menggunakan NaOH pada serat alam rami terhadap kandungan selulosa serat, sifat fisik dan kekuatan tarik serat alam rami. Serat mendapat perlakuan NaOH dengan variasi konsentrasi 0, 2.5, 5, 7.5% dan dibandingkan dengan rami yang didekortikasi ( green ramie ). Hasil penelitian menunjukkan bahwa perlakuan NaOH menyebabkan terjadinya degradasi lignin, hemiselulosa dan juga selulosa serat rami. Dari pengamatan menggunakan SEM (Scanning Electro Microscop y) terlihat bahwa permukaan serat rami setelah mengalami chemical treatment menjadi lebih kasar dibandingkan dengan sebelum mengalami perlakuan. Penurunan kandungan selulosa serat rami itu akan menyebabkan turunnya kekuatan. Kekuatan tarik serat rami terkecil sebesar 707.083 MPa pada perlakuan NaOH 7.5 %. Hasil penelitian ini selanjutnya digunakan sebagai acuan perlakuan awal pada serat alam rami untuk pembuatan material bionanokomposit. Kata kunci : serat alam ra...
Tapioca starch biocomposites reinforced dragon fruit root fiber was successfully produced. As muc... more Tapioca starch biocomposites reinforced dragon fruit root fiber was successfully produced. As much 0, 2, 4 and 6% fiber fractions (from dry starch weight basis) were used as reinforcement in biocomposites. The fabrication of biocomposites was solution casting method. Moisture absorption testing was used to know the percentage of moisture absorption. The functional group of biocomposites was determined by FTIR (Fourier Transform Infra-Red) characterization. The moisture absorption percentage of tapioca starch film was 21,7%. This result was higher than fiber-reinforced biocomposites film. This phenomenon was supported by FTIR analysis on functional group (water absorption band) at wavenumber 1647 cm-1. In this wavenumber, tapioca starch film has higher absorbance than fiberreinforced biocomposites film.
Pada penelitian ini telah diproduksi dan dikarakterisasi komposit bioplastik dari partikel selulo... more Pada penelitian ini telah diproduksi dan dikarakterisasi komposit bioplastik dari partikel selulosa serat rami (Cellulose Micro Fibers/CMF) untuk memperkuat komposit bioplastik bermatriks pati tapioka. CMF rami diproduksi menggunakan metode milling (CMFM) dan ultrasonikasi (CMFU) dengan ukuran masing-masing adalah 3,51 µm dan 0,388 µm. Pembuatan dan karakterisasi komposit bioplastik dilakukan dengan metode casting menggunakan gliserol sebagai plastisizer, dan penambahan filler CMF rami. Sifat fisik, kekuatan tarik, struktur dan termal komposit bioplastik dikarakterisasi menggunakan SEM, UTM, XRD, dan DSC. Hasil pengujian menunjukkan bahwa ukuran dan konsentrasi CMF secara signifikan mempengaruhi fisik bioplastik komposit. Dari hasil SEM menunjukkan bahwa filler CMF berinteraksi dengan matriks pati tapioka, dimana bioplastik dengan CMF rami berukuran kecil memperlihatkan struktur kompak dan permukaan yang lebih homogen. Nilai optimum kekuatan tarik terjadi pada penambahan 8% (w/w) CM...
Indonesian Journal of Electrical Engineering and Computer Science, 2019
Polymer insulators tend to fail because of the climatic and environmental conditions. The failure... more Polymer insulators tend to fail because of the climatic and environmental conditions. The failure occurs when the surface of insulator is contaminated by sea salt or cement dust which lead to partial discharge (PD). Leakage currents will increase by PD that causes deterioration of insulation. To predict the insulation failures, an adaptive neurofuzzy inference system (ANFIS) method using initial color detection processes are proposed to estimate the leakage currents based on the polymer insulator thermal images (infrared signature). In this study, the sodium chloride and kaolin are used as pollutants of the polymer insulator according to IEC 60507 standards. Then, the insulator is tested in the laboratory using AC high voltage applied at 18 kV where the temperature detection is controlled at 26° C and 70% RH (relative humidity). The percentage of colors (Red, Yellow, and Blue) from the thermal image is measured using the color detection method. Correspond to the color percentage, t...
This paper reports estimates of leakage currents based on thermal images (infrared) of polymer is... more This paper reports estimates of leakage currents based on thermal images (infrared) of polymer isolators using color detection methods. In this study, laboratory pollution performance tests using sodium chloride and kaolin were carried out in accordance with the IEC 60507 standard with AC high voltage at 18kV. The severity of pollution is controlled and indicated by ESDD values of heavy pollutants, conditions of relative humidity controlled at 70RH and temperature of 26 0 C. The color detection method is used to obtain the color percentage of thermal images. The ANFIS method predicts leakage currents from contaminated polymer insulators with input from the percentage of thermal image color. The results show that the leakage current can be estimated based on infrared image analysis with a color detection method, where each current leakage level correlates with red, yellow and blue.
Induction motors are the most electric motors widely used in the community, both in the industria... more Induction motors are the most electric motors widely used in the community, both in the industrial and in the household applications. The power and efficiency of the motors are determined by the type of ferromagnetic material used in the core of the motor. If a very good ferromagnetic material with high permeability is applied to the core of the induction motor, then both the energy conversion and the efficiency of the motor will increase. But, if the ferromagnetic material is not good with low permeability is used in the induction motor, of course, the conversion of energy generated by the motor will be low so that the motor efficiency becomes decreased. In other cases, when ferromagnetic materials with high permeability are used, these ferromagnetic materials will become more fragile than using ferromagnetic materials with lower permeability. Therefore, a good strategy is needed in designing the core material of the induction motor. This study was intended to provide an overview of the potential use of a composite material of Fe and ferromagnetic material that was made in the Graded Magnetostrictive Layers. This research was conducted using several studies of the results of research on the composite material of the magnet. The results of the study show that a composite material of Fe and ferromagnetic materials provided a great potential in applying to induction motors to increase power and efficiency of the motor.
This research has found a new approach to improving the conductivity of bacterial cellulose BC/Pp... more This research has found a new approach to improving the conductivity of bacterial cellulose BC/Ppy bio composite films prepared using pulling. A wet BC pellicle is immersed in a liquid Ppy semiconductor for 30 minutes. The wet films was pulled out using a tensile testing machine. The results show that, after pulling, the conductivity of the films became better parallel to the sample drawing direction. Compared to the non-pulled out film, the pulled out film had higher conductivity (σ = 19.2 x 10-3 S/cm), increasing by 153%. The conductivity of films can still improve significantly because deformation during sample preparation in wet conditions.
Over the past three decades, chemical and biological water contamination has become a major conce... more Over the past three decades, chemical and biological water contamination has become a major concern, particularly in the industrialized world. Heavy metals, aromatic compounds, and dyes are among the harmful substances that contribute to water pollution, which jeopardies the human health. For this reason, it is of the utmost importance to locate methods for the cleanup of wastewater that are not genuinely effective. Owing to its non-toxicity, biodegradability, and biocompatibility, starch is a naturally occurring polysaccharide that scientists are looking into as a possible environmentally friendly material for sustainable water remediation. Starch could exhibit significant adsorption capabilities towards pollutants with the substitution of amide, amino, carboxyl, and other functional groups for hydroxyl groups. Starch derivatives may effectively remove contaminants such as oil, organic solvents, pesticides, heavy metals, dyes, and pharmaceutical pollutants by employing adsorption t...
Nanocellulose: from biosources to nanofiber and their applications
Physical Sciences Reviews
Nanocellulose is a product of cellulose, a sustainable and plentiful resource. It’s distinctive n... more Nanocellulose is a product of cellulose, a sustainable and plentiful resource. It’s distinctive nanoscale structure makes it a versatile, green and interesting material for a variety of applications. This article describes in detail the biosources of nanocellulose, the types and characteristics of nanocellulose, and the techniques used to produce nanocellulose fibers. The mechanical properties and morphologies of nanocellulose fibers are addressed in depth, along with their prospective applications in sectors, including paper packaging, building materials, composites, biomedicine, energy storage and filtration. In addition, the current state of nanocellulose research, including the opportunities in the field, as well as the future prospects of nanocellulose as a viable and sustainable material for a vast array of applications, are discussed.
Developing a conductive cellulose film without any metal compounds remains challenging, though in... more Developing a conductive cellulose film without any metal compounds remains challenging, though in great demand. However, cellulose film prepared from bacterial cellulose (BC) powder without any metal compounds has poor tensile, physical, and electrical properties, thus limiting its application. Herein, this study aims to prepare and characterize an all-cellulose film from 2,2,6,6-Tetramethylpiperidin-1-yl)oxyl (TEMPO)-oxidized bacterial cellulose (TOBC) powders without adding metal compounds and treated by ultrasonication. TOBC powders are sonicated with various powers of 250, 500, and 750 W for 20 min without any other substance. It was proved that increasing the ultrasonication power level resulted in a significant improvement in the properties of the film. The ultrasonication of 750 W increased tensile strength by 85%, toughness by 308%, light transmittance by 542%, and electrical conductivity by 174% compared to the nonsonicated film. A light-emitting diode connected to a power ...
This study examined the effect of sonication on FTIR and stability at various temperatures in wat... more This study examined the effect of sonication on FTIR and stability at various temperatures in water-based lubricants with a mixture of Carboxymethyl Cellulose (1wt%) and Uncaria Gambir extract (1wt% and 2wt%). The sample was prepared by mixing the two materials into distilled water using a magnetic stirrer and sonicator with time variations of 5 and 10 minutes. Before mixing, the Uncaria Gambir extract solution with water is first centrifuged to remove the dregs in the Uncaria Gambir extract powder. Stability was carried out in an open room (28oC), drying oven (50oC), and refrigerator (5oC). The stability test results showed that the mixture of Carboxymethyl Cellulose and Uncaria Gambir had good stability at all temperatures after sonication for a short duration. The longer sonication duration could fuse the fibrils of Carboxymethyl Cellulose, leading to increasing particle size. FTIR results also show that there is no chemical reaction that occurs. After adding the gambier, there w...
There is an increasing demand for food packaging materials that are safe for the environment and ... more There is an increasing demand for food packaging materials that are safe for the environment and human health. Pure polyvinyl alcohol (PVA) film is non-toxic and transparent but has poor UV-light shielding, thermal and moisture resistance, and antibacterial activity. Our previous work prepared and characterized a biofilm derived from PVA and edible Uncaria gambir extract (UG). The film has antibacterial properties and is anti-UV and flexible. However, UG is hydrophilic, making this film have low moisture absorption. To improve these properties, we trialed adding boric acid (BA) and UG into the PVA. This present study aims to characterize pure PVA film and blend films resulting from mixing PVA (10%), BA (0.5%), and UG (1%). It was found that the PVA/UG/BA film presented the best performance in terms of UV light absorption, tensile properties, thermal and moisture resistance, and antibacterial activity. This blend sample absorbs about 98% of the UV light at 400 nm wavelength without s...
Dragon fruit root fiber used as a reinforcement in the biocomposites film of cassava starch. The ... more Dragon fruit root fiber used as a reinforcement in the biocomposites film of cassava starch. The production method of biocomposites film was solution casting. The cassava starch serves as the matrix in the biocomposites film. The variation of amount fiber in matrix was 2, 4 and 6% from dry starch weight basis. Isolation of dragon fruit root fiber used alkalization and bleaching process with NaOH, NaClO2 and CH3COOH, respectively. Glycerol was used as plasticizers. Mechanical properties of biocomposites was determined by tensile test. The result shows that, tensile strength increased 200% after the addition of 6% fiber compared to pure starch film. Tensile test data was supported by X-Ray Difraction (XRD). Keywords: Biocomposite, Cassava Starch, Dragon fruit root fiber, Mechanical properties, XRD
There has been much effort to provide eco-friendly and biodegradable materials for the next gener... more There has been much effort to provide eco-friendly and biodegradable materials for the next generation of composite products owing to global environmental concerns and increased awareness of renewable green resources. This review article uniquely highlights the use of green composites from natural fiber, particularly with regard to the development and characterization of chitosan, natural-fiber-reinforced chitosan biopolymer, chitosan blends, and chitosan nanocomposites. Natural fiber composites have a number of advantages such as durability, low cost, low weight, high specific strength, non-abrasiveness, equitably good mechanical properties, environmental friendliness, and biodegradability. Findings revealed that chitosan is a natural fiber that falls to the animal fiber category. As it has a biomaterial form, chitosan can be presented as hydrogels, sponges, film, and porous membrane. There are different processing methods in the preparation of chitosan composites such as solution ...
Polylactic acid (PLA) is a thermoplastic polymer produced from lactic acid that has been chiefly ... more Polylactic acid (PLA) is a thermoplastic polymer produced from lactic acid that has been chiefly utilized in biodegradable material and as a composite matrix material. PLA is a prominent biomaterial that is widely used to replace traditional petrochemical-based polymers in various applications owing environmental concerns. Green composites have gained greater attention as ecological consciousness has grown since they have the potential to be more appealing than conventional petroleum-based composites, which are toxic and nonbiodegradable. PLA-based composites with natural fiber have been extensively utilized in a variety of applications, from packaging to medicine, due to their biodegradable, recyclable, high mechanical strength, low toxicity, good barrier properties, friendly processing, and excellent characteristics. A summary of natural fibers, green composites, and PLA, along with their respective properties, classification, functionality, and different processing methods, are d...
The raw data PD measurement results by using a computer usually contain noise that can lead to mi... more The raw data PD measurement results by using a computer usually contain noise that can lead to miss interpretation. So as to obtain an accurate diagnosis, then this noise must be separated from the raw data. In this study, the electrodes used were needle-plane electrode and the samples tested are polymer films placed on the electrode plane and the air gap is located between the needle and polymer films. There are two types of arrangement of the electrodes, the first electrode needle wrapped with the film and the second polymer are not wrapped with polymer films. To separate the data PD of raw-data is necessary algorithms that can automatically select the threshold value of the standard deviation value. To obtain the optimum value, the threshold value selected based on the standard deviation of each value segment. The results show that this method has been used to distinguish between the electrode pattern PD wrapped or not wrapped polymer.
Penelitian ini bertujuan untuk mengetahui pengaruh chemical treatment menggunakan NaOH pada ser... more Penelitian ini bertujuan untuk mengetahui pengaruh chemical treatment menggunakan NaOH pada serat alam rami terhadap kandungan selulosa serat, sifat fisik dan kekuatan tarik serat alam rami. Serat mendapat perlakuan NaOH dengan variasi konsentrasi 0, 2.5, 5, 7.5% dan dibandingkan dengan rami yang didekortikasi ( green ramie ). Hasil penelitian menunjukkan bahwa perlakuan NaOH menyebabkan terjadinya degradasi lignin, hemiselulosa dan juga selulosa serat rami. Dari pengamatan menggunakan SEM (Scanning Electro Microscop y) terlihat bahwa permukaan serat rami setelah mengalami chemical treatment menjadi lebih kasar dibandingkan dengan sebelum mengalami perlakuan. Penurunan kandungan selulosa serat rami itu akan menyebabkan turunnya kekuatan. Kekuatan tarik serat rami terkecil sebesar 707.083 MPa pada perlakuan NaOH 7.5 %. Hasil penelitian ini selanjutnya digunakan sebagai acuan perlakuan awal pada serat alam rami untuk pembuatan material bionanokomposit. Kata kunci : serat alam ra...
Tapioca starch biocomposites reinforced dragon fruit root fiber was successfully produced. As muc... more Tapioca starch biocomposites reinforced dragon fruit root fiber was successfully produced. As much 0, 2, 4 and 6% fiber fractions (from dry starch weight basis) were used as reinforcement in biocomposites. The fabrication of biocomposites was solution casting method. Moisture absorption testing was used to know the percentage of moisture absorption. The functional group of biocomposites was determined by FTIR (Fourier Transform Infra-Red) characterization. The moisture absorption percentage of tapioca starch film was 21,7%. This result was higher than fiber-reinforced biocomposites film. This phenomenon was supported by FTIR analysis on functional group (water absorption band) at wavenumber 1647 cm-1. In this wavenumber, tapioca starch film has higher absorbance than fiberreinforced biocomposites film.
Pada penelitian ini telah diproduksi dan dikarakterisasi komposit bioplastik dari partikel selulo... more Pada penelitian ini telah diproduksi dan dikarakterisasi komposit bioplastik dari partikel selulosa serat rami (Cellulose Micro Fibers/CMF) untuk memperkuat komposit bioplastik bermatriks pati tapioka. CMF rami diproduksi menggunakan metode milling (CMFM) dan ultrasonikasi (CMFU) dengan ukuran masing-masing adalah 3,51 µm dan 0,388 µm. Pembuatan dan karakterisasi komposit bioplastik dilakukan dengan metode casting menggunakan gliserol sebagai plastisizer, dan penambahan filler CMF rami. Sifat fisik, kekuatan tarik, struktur dan termal komposit bioplastik dikarakterisasi menggunakan SEM, UTM, XRD, dan DSC. Hasil pengujian menunjukkan bahwa ukuran dan konsentrasi CMF secara signifikan mempengaruhi fisik bioplastik komposit. Dari hasil SEM menunjukkan bahwa filler CMF berinteraksi dengan matriks pati tapioka, dimana bioplastik dengan CMF rami berukuran kecil memperlihatkan struktur kompak dan permukaan yang lebih homogen. Nilai optimum kekuatan tarik terjadi pada penambahan 8% (w/w) CM...
Indonesian Journal of Electrical Engineering and Computer Science, 2019
Polymer insulators tend to fail because of the climatic and environmental conditions. The failure... more Polymer insulators tend to fail because of the climatic and environmental conditions. The failure occurs when the surface of insulator is contaminated by sea salt or cement dust which lead to partial discharge (PD). Leakage currents will increase by PD that causes deterioration of insulation. To predict the insulation failures, an adaptive neurofuzzy inference system (ANFIS) method using initial color detection processes are proposed to estimate the leakage currents based on the polymer insulator thermal images (infrared signature). In this study, the sodium chloride and kaolin are used as pollutants of the polymer insulator according to IEC 60507 standards. Then, the insulator is tested in the laboratory using AC high voltage applied at 18 kV where the temperature detection is controlled at 26° C and 70% RH (relative humidity). The percentage of colors (Red, Yellow, and Blue) from the thermal image is measured using the color detection method. Correspond to the color percentage, t...
This paper reports estimates of leakage currents based on thermal images (infrared) of polymer is... more This paper reports estimates of leakage currents based on thermal images (infrared) of polymer isolators using color detection methods. In this study, laboratory pollution performance tests using sodium chloride and kaolin were carried out in accordance with the IEC 60507 standard with AC high voltage at 18kV. The severity of pollution is controlled and indicated by ESDD values of heavy pollutants, conditions of relative humidity controlled at 70RH and temperature of 26 0 C. The color detection method is used to obtain the color percentage of thermal images. The ANFIS method predicts leakage currents from contaminated polymer insulators with input from the percentage of thermal image color. The results show that the leakage current can be estimated based on infrared image analysis with a color detection method, where each current leakage level correlates with red, yellow and blue.
Induction motors are the most electric motors widely used in the community, both in the industria... more Induction motors are the most electric motors widely used in the community, both in the industrial and in the household applications. The power and efficiency of the motors are determined by the type of ferromagnetic material used in the core of the motor. If a very good ferromagnetic material with high permeability is applied to the core of the induction motor, then both the energy conversion and the efficiency of the motor will increase. But, if the ferromagnetic material is not good with low permeability is used in the induction motor, of course, the conversion of energy generated by the motor will be low so that the motor efficiency becomes decreased. In other cases, when ferromagnetic materials with high permeability are used, these ferromagnetic materials will become more fragile than using ferromagnetic materials with lower permeability. Therefore, a good strategy is needed in designing the core material of the induction motor. This study was intended to provide an overview of the potential use of a composite material of Fe and ferromagnetic material that was made in the Graded Magnetostrictive Layers. This research was conducted using several studies of the results of research on the composite material of the magnet. The results of the study show that a composite material of Fe and ferromagnetic materials provided a great potential in applying to induction motors to increase power and efficiency of the motor.
Uploads
Papers by Hairul Abral