Identification of the potential of cacao peel as the basic material of environmentally friendly s... more Identification of the potential of cacao peel as the basic material of environmentally friendly supercapacitor electrodes had been identified. This identification was carried out through analysis of specific dimensions, densities, and capacitances. Activated carbon electrodes were made by a combination of chemical and physics activation methods. The technique of preparing carbon electrodes started from pre-carbonization, milling, chemical activation, pellet making, carbonization, and completed it with physics activation. In addition, the chemical activation applied 0.3 M KOH activator, whereas the physical activation used CO2 gas at a temperature of 700 o C. The physical properties were tested by density and X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Energy Dipersive X-Ray (EDX). While the electrochemical properties were tested using the Ciclic Voltammetric (CV) method. The results showed that the mass, diameter, thickness, and density of the electrode decreased after passing the carbonizationactivation process. A value of 2θ in the range of 23,569 o for the reflection fields 002 and 44,781 o for the reflection field 100 was obtained in the XRD measurements. The X-ray diffraction curve pointed out that the surface area of C 0,3 M sample was sizeable with the Lc value and lattice distance d002 around 20,01669 Å and 3,771705 Å. SEM analysis indicated the presence of pores between particles spread almost evenly on the surface of the sample, with an irregular and elongated shape. EDX testing showed carbon element of 87.05% while atomic percentage of 91.02%, and correspondently, electrochemical test showed the value of specific capacitance obtained at a concentration of 0.3 M was 90.2 F/gr with a density of 0.850gr/cm 3. From the results of the tests obtained, it was shown that cacao peels was very potential to be used as electrodes for supercapacitors.
Ti-6Al-4V ELI is one of the titanium alloys commonly used as an implant material for its good bio... more Ti-6Al-4V ELI is one of the titanium alloys commonly used as an implant material for its good biocompatibility. However, it has problems related to its corrosion behavior, especially when it is used for a long time. This study aimed to analyze the corrosion behavior of the implant material Ti-6Al-4V ELI in Hanks’ Balanced Salt Solution (HBSS) for a certain period, using the weight loss method in HBSS as the corrosive medium at 37°C. The immersion time was varied from two, four, until six weeks. Before immersion, the sample was thermomechanically treated with a combination of solution heat treatment at a temperature of 950°C and a holding time of 1 hour, water quenching, plastic deformation with deformation variations of 10%, 15%, and 20%, and, finally, aging heat treatment at a temperature of 550°C and holding time for 1.5 hours. The study results show that thermomechanical treatment and increased plastic deformation could reduce the corrosion rate and the metal ions released into the solution. These findings were evidenced by the corrosion rates of the pre-thermomechanical and the thermomechanical Ti-6Al-4V ELI with deformations of 10%, 15%, and 20% at the 6-week immersion of 6.57 x 10-6 mmpy, 4.27 x 10-6 mmpy, 3.89 x 10-6 mmpy, and 2.76 x 10-6 mmpy, respectively, and the metal ions released of 7.3 μg/L, 7 μg/L, 6.3 μg/L, and 6 μg/L, respectively. The corrosion rate of Ti-6Al-4V ELI under thermomechanical treatment, namely 2.76 x 10-6 mmpy, was the lowest compared to other materials in HBSS, while the highest one was that of Ti-6Al-7Nb of 3.05 x10-2 mmpy. In addition, the study results show that Ti-6Al-4V ELI under thermomechanical treatment is the best material compared to others for biomedical applications, based on corrosion resistance and metal ions released into HBSS.
... Muhammad Hanafiah, Direktur Ppliteknik Universitas Ándalas Padang, atas rekomendasi yang tela... more ... Muhammad Hanafiah, Direktur Ppliteknik Universitas Ándalas Padang, atas rekomendasi yang telah diberikan; Prof. ... Naek Pakpahan, M.Si dari PT Jerman Motor yang telah membantu kelancaran penelitian ini; Tohir dari PT Marga Mandiri Manunggal Metal; Ir. ...
Manutech : Jurnal Teknologi Manufaktur, Dec 7, 2020
A research has been conducted about Troubleshooting that occurs in the Caterpillar Engine G3408 g... more A research has been conducted about Troubleshooting that occurs in the Caterpillar Engine G3408 generator Set which aims to analyze the causes of the hydraulic lock and determine how to solve the problems that occur in the Caterpillar G3408 Engine Generator Set. The research method is to perform detection, diagnostic, and repair on the engine by doing a visual check, looking for the root of the problem and doing the test. The results are engine has a hydraulic lock caused by a damaged one of the components of the Air Intake and Exhaust System. The after cooler is also damaged due to its long service life, causing the coolant to enter the combustion chamber. From the overall analysis it is concluded that the cause of engine failure is one of the components is damaged due to a long service life and to overcome this is doing repair and replacement of components on the After cooler with new components and do the periodic maintenance on the Caterpillar G3408 Engine Generator Set.
To maximize the function of the mosque as a place of worship, a community service team has carrie... more To maximize the function of the mosque as a place of worship, a community service team has carried out together in the form of counseling and donations. This is done because mosques have a very strategic function in Islamic society, both as places of worship and as media centers for holistic development of the people. This service team is trying to optimize the function of the mosque as a center for community empowerment activities. This community service is motivated by the facilities and infrastructure of the Nurul Hikmah mosque which are still inadequate for the needs and comfort of worship, such as: carpets, loudspeakers, mosque clocks, towers and pulpits. Even the implementation of mosque management has not been so evenly distributed so that it has not been accompanied by social welfare efforts for the community. The purpose of this service is to find out the condition of the social welfare of the community. Community Service is the third dharma of higher education tri dharma. ...
Community service has been carried out by a team from the Padang State Polytechnic. This activity... more Community service has been carried out by a team from the Padang State Polytechnic. This activity was carried out due to concerns about the large amount of inorganic household waste that had accumulated in the Guguak Malintang sub-district, Padang Panjang Timur sub- district, which had not been processed, making members of the Sakinah waste bank in the sub-district want to process it into useful materials. This desire was responded directly by the service team from the Padang State Polytechnic, so that cooperation was established in the form of a partnership. The purpose of the activity is to contribute to the application of science and technology in carrying out the tri dharma of higher education, namely the third dharma of community service. The activity took place thanks to the collaboration of the community service team from the Padang State Polytechnic with the Sakinah waste bank which is a partner. This plastic waste recycling training aims to enable participants to have the s...
Journal of Biomimetics, Biomaterials and Biomedical Engineering
One of factor causing the failure of Ti-6Al-4V Extra Low Interstitial (ELI)-based material implan... more One of factor causing the failure of Ti-6Al-4V Extra Low Interstitial (ELI)-based material implants, does not have bioactive properties in the implantation process, thus not supporting the osseointegration process in the body. For this reason, coating with hydroxyapatite (HA) suspension is necessary. This research used the dip-coating method and added Zirconium Oxide (ZrO2) into nanosized commercial HA to be suspensions (17%wt and 20%wt) to strengthen the adhesion of the coating. The specimens were heated at 800, 900, and 950°C to densify the layers. Bioactivity increased along with the increasing calcium/phosphate (Ca/P) ratio of the HA layers in the test specimens. The specimens were immersed in Simulated Body Fluid (SBF), namely Hank’s Solution, for 1, 2, 3, and 4 weeks. ZrO2 added to the HA suspensions of Ti-6Al-4V ELI can increase the Ca/P ratio from 1.51 in the first immersion week to 1.62 in the fourth. The bioactivity level is also proven by the accumulation of calcium and p...
IOP Conference Series: Materials Science and Engineering, 2021
Ti-6Al-4V Extra Low Intertitial (ELI), a type of titanium alloy that is commonly used for implant... more Ti-6Al-4V Extra Low Intertitial (ELI), a type of titanium alloy that is commonly used for implant material. However, use of Ti-6Al-4V ELI still has some problems. The main one is oxide layer on the surface can be detached during application due to corrosion process. Such corrosion debris is a toxic substance to the human body. It is, therefore, necessary to modify the surface of the implant to avoid corrosion process by using coating method. A good coating material for orthopedic implants comes from ceramics, namely hydroxyapatite (HA). However, there are also an obstacle, HA coating on titanium, sometimes not evenly across the surface, causing cracks on the coating layer surface. There are two methods that are often used in coating materials, namely Electrophoretic Deposition (EPD) and Dip Coating. This study analyzed number of literatures using a searching engine of international reputable journals Science Direct, Pubmed on biomaterials and biomedicine fields using the keywords of...
Many studies in mathematics education discusses the relationship of latent variables that are mea... more Many studies in mathematics education discusses the relationship of latent variables that are measured directly. If latent variables measure directly, it will cause a bias in estimation. It is necessary to measure instruments that explain the relationship between latent variables and indicator variables, which should not be measured directly. This study aimed to analyze indicators of interest and motivation to learn mathematics, while the method we used is the Confirmatory Factor Analysis (CFA). Indicators of the interest in learning mathematics are 1) Feeling of Happiness, 2) Student Curiosity, 3) Student Attention, 4) Student Involvement, while the indicators for motivation are 1) Perseverance in Learning, 2) Facing Difficulties Ability, 3) Sharpness in Attention 4) Achievement in Learning, 5) Independent in Learning. Four indicators of interest in mathematics show that only two indicators are qualified based on the Kaiser Mayer Oikin (KMO) score of 0.611 for the indicator of stud...
Identification of the potential of cacao peel as the basic material of environmentally friendly s... more Identification of the potential of cacao peel as the basic material of environmentally friendly supercapacitor electrodes had been identified. This identification was carried out through analysis of specific dimensions, densities, and capacitances. Activated carbon electrodes were made by a combination of chemical and physics activation methods. The technique of preparing carbon electrodes started from pre-carbonization, milling, chemical activation, pellet making, carbonization, and completed it with physics activation. In addition, the chemical activation applied 0.3 M KOH activator, whereas the physical activation used CO2 gas at a temperature of 700 o C. The physical properties were tested by density and X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Energy Dipersive X-Ray (EDX). While the electrochemical properties were tested using the Ciclic Voltammetric (CV) method. The results showed that the mass, diameter, thickness, and density of the electrode decreased after passing the carbonizationactivation process. A value of 2θ in the range of 23,569 o for the reflection fields 002 and 44,781 o for the reflection field 100 was obtained in the XRD measurements. The X-ray diffraction curve pointed out that the surface area of C 0,3 M sample was sizeable with the Lc value and lattice distance d002 around 20,01669 Å and 3,771705 Å. SEM analysis indicated the presence of pores between particles spread almost evenly on the surface of the sample, with an irregular and elongated shape. EDX testing showed carbon element of 87.05% while atomic percentage of 91.02%, and correspondently, electrochemical test showed the value of specific capacitance obtained at a concentration of 0.3 M was 90.2 F/gr with a density of 0.850gr/cm 3. From the results of the tests obtained, it was shown that cacao peels was very potential to be used as electrodes for supercapacitors.
Ti-6Al-4V ELI is one of the titanium alloys commonly used as an implant material for its good bio... more Ti-6Al-4V ELI is one of the titanium alloys commonly used as an implant material for its good biocompatibility. However, it has problems related to its corrosion behavior, especially when it is used for a long time. This study aimed to analyze the corrosion behavior of the implant material Ti-6Al-4V ELI in Hanks’ Balanced Salt Solution (HBSS) for a certain period, using the weight loss method in HBSS as the corrosive medium at 37°C. The immersion time was varied from two, four, until six weeks. Before immersion, the sample was thermomechanically treated with a combination of solution heat treatment at a temperature of 950°C and a holding time of 1 hour, water quenching, plastic deformation with deformation variations of 10%, 15%, and 20%, and, finally, aging heat treatment at a temperature of 550°C and holding time for 1.5 hours. The study results show that thermomechanical treatment and increased plastic deformation could reduce the corrosion rate and the metal ions released into the solution. These findings were evidenced by the corrosion rates of the pre-thermomechanical and the thermomechanical Ti-6Al-4V ELI with deformations of 10%, 15%, and 20% at the 6-week immersion of 6.57 x 10-6 mmpy, 4.27 x 10-6 mmpy, 3.89 x 10-6 mmpy, and 2.76 x 10-6 mmpy, respectively, and the metal ions released of 7.3 μg/L, 7 μg/L, 6.3 μg/L, and 6 μg/L, respectively. The corrosion rate of Ti-6Al-4V ELI under thermomechanical treatment, namely 2.76 x 10-6 mmpy, was the lowest compared to other materials in HBSS, while the highest one was that of Ti-6Al-7Nb of 3.05 x10-2 mmpy. In addition, the study results show that Ti-6Al-4V ELI under thermomechanical treatment is the best material compared to others for biomedical applications, based on corrosion resistance and metal ions released into HBSS.
... Muhammad Hanafiah, Direktur Ppliteknik Universitas Ándalas Padang, atas rekomendasi yang tela... more ... Muhammad Hanafiah, Direktur Ppliteknik Universitas Ándalas Padang, atas rekomendasi yang telah diberikan; Prof. ... Naek Pakpahan, M.Si dari PT Jerman Motor yang telah membantu kelancaran penelitian ini; Tohir dari PT Marga Mandiri Manunggal Metal; Ir. ...
Manutech : Jurnal Teknologi Manufaktur, Dec 7, 2020
A research has been conducted about Troubleshooting that occurs in the Caterpillar Engine G3408 g... more A research has been conducted about Troubleshooting that occurs in the Caterpillar Engine G3408 generator Set which aims to analyze the causes of the hydraulic lock and determine how to solve the problems that occur in the Caterpillar G3408 Engine Generator Set. The research method is to perform detection, diagnostic, and repair on the engine by doing a visual check, looking for the root of the problem and doing the test. The results are engine has a hydraulic lock caused by a damaged one of the components of the Air Intake and Exhaust System. The after cooler is also damaged due to its long service life, causing the coolant to enter the combustion chamber. From the overall analysis it is concluded that the cause of engine failure is one of the components is damaged due to a long service life and to overcome this is doing repair and replacement of components on the After cooler with new components and do the periodic maintenance on the Caterpillar G3408 Engine Generator Set.
To maximize the function of the mosque as a place of worship, a community service team has carrie... more To maximize the function of the mosque as a place of worship, a community service team has carried out together in the form of counseling and donations. This is done because mosques have a very strategic function in Islamic society, both as places of worship and as media centers for holistic development of the people. This service team is trying to optimize the function of the mosque as a center for community empowerment activities. This community service is motivated by the facilities and infrastructure of the Nurul Hikmah mosque which are still inadequate for the needs and comfort of worship, such as: carpets, loudspeakers, mosque clocks, towers and pulpits. Even the implementation of mosque management has not been so evenly distributed so that it has not been accompanied by social welfare efforts for the community. The purpose of this service is to find out the condition of the social welfare of the community. Community Service is the third dharma of higher education tri dharma. ...
Community service has been carried out by a team from the Padang State Polytechnic. This activity... more Community service has been carried out by a team from the Padang State Polytechnic. This activity was carried out due to concerns about the large amount of inorganic household waste that had accumulated in the Guguak Malintang sub-district, Padang Panjang Timur sub- district, which had not been processed, making members of the Sakinah waste bank in the sub-district want to process it into useful materials. This desire was responded directly by the service team from the Padang State Polytechnic, so that cooperation was established in the form of a partnership. The purpose of the activity is to contribute to the application of science and technology in carrying out the tri dharma of higher education, namely the third dharma of community service. The activity took place thanks to the collaboration of the community service team from the Padang State Polytechnic with the Sakinah waste bank which is a partner. This plastic waste recycling training aims to enable participants to have the s...
Journal of Biomimetics, Biomaterials and Biomedical Engineering
One of factor causing the failure of Ti-6Al-4V Extra Low Interstitial (ELI)-based material implan... more One of factor causing the failure of Ti-6Al-4V Extra Low Interstitial (ELI)-based material implants, does not have bioactive properties in the implantation process, thus not supporting the osseointegration process in the body. For this reason, coating with hydroxyapatite (HA) suspension is necessary. This research used the dip-coating method and added Zirconium Oxide (ZrO2) into nanosized commercial HA to be suspensions (17%wt and 20%wt) to strengthen the adhesion of the coating. The specimens were heated at 800, 900, and 950°C to densify the layers. Bioactivity increased along with the increasing calcium/phosphate (Ca/P) ratio of the HA layers in the test specimens. The specimens were immersed in Simulated Body Fluid (SBF), namely Hank’s Solution, for 1, 2, 3, and 4 weeks. ZrO2 added to the HA suspensions of Ti-6Al-4V ELI can increase the Ca/P ratio from 1.51 in the first immersion week to 1.62 in the fourth. The bioactivity level is also proven by the accumulation of calcium and p...
IOP Conference Series: Materials Science and Engineering, 2021
Ti-6Al-4V Extra Low Intertitial (ELI), a type of titanium alloy that is commonly used for implant... more Ti-6Al-4V Extra Low Intertitial (ELI), a type of titanium alloy that is commonly used for implant material. However, use of Ti-6Al-4V ELI still has some problems. The main one is oxide layer on the surface can be detached during application due to corrosion process. Such corrosion debris is a toxic substance to the human body. It is, therefore, necessary to modify the surface of the implant to avoid corrosion process by using coating method. A good coating material for orthopedic implants comes from ceramics, namely hydroxyapatite (HA). However, there are also an obstacle, HA coating on titanium, sometimes not evenly across the surface, causing cracks on the coating layer surface. There are two methods that are often used in coating materials, namely Electrophoretic Deposition (EPD) and Dip Coating. This study analyzed number of literatures using a searching engine of international reputable journals Science Direct, Pubmed on biomaterials and biomedicine fields using the keywords of...
Many studies in mathematics education discusses the relationship of latent variables that are mea... more Many studies in mathematics education discusses the relationship of latent variables that are measured directly. If latent variables measure directly, it will cause a bias in estimation. It is necessary to measure instruments that explain the relationship between latent variables and indicator variables, which should not be measured directly. This study aimed to analyze indicators of interest and motivation to learn mathematics, while the method we used is the Confirmatory Factor Analysis (CFA). Indicators of the interest in learning mathematics are 1) Feeling of Happiness, 2) Student Curiosity, 3) Student Attention, 4) Student Involvement, while the indicators for motivation are 1) Perseverance in Learning, 2) Facing Difficulties Ability, 3) Sharpness in Attention 4) Achievement in Learning, 5) Independent in Learning. Four indicators of interest in mathematics show that only two indicators are qualified based on the Kaiser Mayer Oikin (KMO) score of 0.611 for the indicator of stud...
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