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Full-Text Articles in Chemical Engineering

Effect Of Alkyd And Polyester Resin Compositions On Corrosion Resistance, Blistering, And Adhesion In Utilization Of Oily Sludge As Anti-Rust Coating Material, Gerets Land Kakalang, Yohanes David Kristianto, Johny Wahyuadi Mudaryoto Dec 2024

Effect Of Alkyd And Polyester Resin Compositions On Corrosion Resistance, Blistering, And Adhesion In Utilization Of Oily Sludge As Anti-Rust Coating Material, Gerets Land Kakalang, Yohanes David Kristianto, Johny Wahyuadi Mudaryoto

Journal of Materials Exploration and Findings

Oil sludge is a waste derived from upstream and downstream activities of the oil and gas industry which is estimated at 10,000 tonnes generated from all PERTAMINA downstream activities spread across various fields, processing units and depots throughout Indonesia. Oil sludge has the same characteristics as asphalt, where asphalt in previous studies can be used as an anti-rust coating, so that the handling of oily sludge can be topped up by reusing and having its own added value. The purpose of this research is to utilise waste oily sludge as an alternative anti-rust coating material and compare alkyd resin and …


Determination Of The Kinetic Parameters Of Cholesterol Oxidation Using Cholesterol Oxidase From Streptomyces Sp., Meka Saima Perdani, Heri Hermansyah, Muhamad Sahlan, Dwini Normayulisa Putri, Teguh Pambudi, Anggi Khairina Hanum Hasibuan Dec 2024

Determination Of The Kinetic Parameters Of Cholesterol Oxidation Using Cholesterol Oxidase From Streptomyces Sp., Meka Saima Perdani, Heri Hermansyah, Muhamad Sahlan, Dwini Normayulisa Putri, Teguh Pambudi, Anggi Khairina Hanum Hasibuan

Makara Journal of Technology

Cholesterol oxidase (CO) was successfully produced from Streptomyces sp. via the submerged fermentation method, and 69 U/mL enzyme activity was obtained. This study aimed to determine cholesterol oxidation kinetics and the production of CO as a catalyst. The enzyme was diluted to 0.15, 0.075, and 0.00375 U/mL for the oxidation reaction. The substrate was also prepared in three concentrations: 3.23, 6.46, and 12.93 mM. The optimization of conditions for enzymatic cholesterol oxidation was investigated through measurement of the effect of initial cholesterol and enzyme concentrations. Cholesterol concentration was rapidly measured via high-performance liquid chromatography (HPLC). The kinetics of CO were …


Kinetics Model Of Cananga (Cananga Odorata) Fresh Flower Extraction Using Microwave Hydrodistillation Method, Darnengsih Darnengsih, Hikmatun Ni’Mah, Mahfud Mahfud, Ayu Chandra Kartika Fitri Dec 2024

Kinetics Model Of Cananga (Cananga Odorata) Fresh Flower Extraction Using Microwave Hydrodistillation Method, Darnengsih Darnengsih, Hikmatun Ni’Mah, Mahfud Mahfud, Ayu Chandra Kartika Fitri

Makara Journal of Science

Recent studies have focused on improving essential oil extraction methods by incorporating advanced technologies, such as microwave-assisted hydrodistillation (MHD). Despite these advancements, further research is necessary to fully understand how different kinetic models influence extraction efficiency. This study evaluates several kinetic models for extracting essential oil from fresh Cananga flowers using MHD, examining how varying microwave power affects extraction rates and correlates with kinetic model parameters. The extraction process involved introducing 200 grams of fresh Cananga flowers in 400 mL of distilled water and subjecting the mixture to microwave power levels of 200 W, 400 W, and 600 W. The …


Synthesis Of Activated Carbon From Coconut Shell And Recycled Styrofoam Nanofiber For Water Filtration, Rahma Dani, Ismet Ismet, Leni Marlina, Rona Alisya, Muhamad Abel Kirana Aldi, Anggi Ludiansyah, Lintang Auliya Kurdiati, Meutia Kamilatun Nuha Ap Idjan, Agung Mataram, Muhammad Rama Almafie, Ida Sriyanti Dec 2024

Synthesis Of Activated Carbon From Coconut Shell And Recycled Styrofoam Nanofiber For Water Filtration, Rahma Dani, Ismet Ismet, Leni Marlina, Rona Alisya, Muhamad Abel Kirana Aldi, Anggi Ludiansyah, Lintang Auliya Kurdiati, Meutia Kamilatun Nuha Ap Idjan, Agung Mataram, Muhammad Rama Almafie, Ida Sriyanti

Makara Journal of Science

Water pollution affects life sustainability; hence, several efforts have been exerted to overcome this problem. For ex-ample, nanofiber membrane technology is introduced to retain solutes while allowing only water molecules to pass through the system. Therefore, this study aimed to maximize the technology for water filtration using the electrospin-ning method by combining Styrofoam waste-based polymer with activated carbon from coconut shell waste (ACCS). The nanofiber diameter produced ranged from 590 nm to 610 nm with porous characteristics and without beads. The carbon content varied from 68.04% to 69.84%, according to the energy dispersive X-ray measurement, demonstrating the composite’s effectiveness. The …


Polyvinyl Alcohol–Red Cabbage Nanofibers As Ph-Responsive Freshness Sensors For Advanced Food Packaging Technology, Foliatini Foliatini, Singgih Wibowo, Henny Rochaeni, Suhartini Suhartini, Fachrurrazie Fachrurrazie, Arzzaq Imanda Prianditya, Pradnadia Putri Hadriansyah, Naura Athira Putri Siregar, Novi Nurpadilah, Putri Alfiani, Maudi Rahim, Endah Sriwahyuni Sep 2024

Polyvinyl Alcohol–Red Cabbage Nanofibers As Ph-Responsive Freshness Sensors For Advanced Food Packaging Technology, Foliatini Foliatini, Singgih Wibowo, Henny Rochaeni, Suhartini Suhartini, Fachrurrazie Fachrurrazie, Arzzaq Imanda Prianditya, Pradnadia Putri Hadriansyah, Naura Athira Putri Siregar, Novi Nurpadilah, Putri Alfiani, Maudi Rahim, Endah Sriwahyuni

Makara Journal of Science

The development of innovative food packaging technologies, particularly those capable of monitoring freshness, has become increasingly important in the food industry. This research explores the development of a pH-responsive freshness sensor using polyvinyl alcohol–red cabbage (PVA/RC) nanofibers. The nanofibers are fabricated through the electrospinning technique and meticulously analyzed via scanning electron microscopy, Fourier-transform infrared (FTIR) spectroscopy, and differential scanning calorimetry (DSC). The results underscore the fine structure of the nanofiber matrix, with an average diameter of ~68 nm. FTIR analysis substantiates the presence of anthocyanin compounds from RC within the PVA/RC nanofibers, which confirms the integration of beneficial components into …


Immobilization Of Ni(Ii) On Amine-Functionalized Mesoporous Silica As Catalyst For Benzyl Alcohol Acetylation Reaction, Wardah Nabilah, Eko Sri Kunarti, Fajar Inggit Pambudi Sep 2024

Immobilization Of Ni(Ii) On Amine-Functionalized Mesoporous Silica As Catalyst For Benzyl Alcohol Acetylation Reaction, Wardah Nabilah, Eko Sri Kunarti, Fajar Inggit Pambudi

Makara Journal of Science

In this study, amine-functionalized and Ni(II)-immobilized mesoporous silica materials were synthesized. This research aimed to synthesize mesoporous silica based on rice husk ash functionalized with amine and immobilized with Ni(II). The activity of amine-functionalized and Ni(II)-immobilized mesoporous silica materials was studied for the acetylation of benzyl alcohol with acetic anhydride as the acetylating agent. First, mesoporous silica was synthesized using rice husk ash using the sol–gel method, followed by amine functionalization using (3-aminopropyl)triethoxysilane (APTES) and Ni(II) immobilization through ultrasonic treatment. The results obtained showed that amine-functionalized and Ni(II)-immobilized mesoporous silica (SiO2/APTES/Ni(II)) were successfully synthesized, confirmed by Fourier transform …


Optimization Of Bioethanol Production Using An Enzymatic Hydrolysis Process With Green Algae (Chaetomorpha) As The Raw Material, Teuku Maimun, Mirna Rahmah Lubis, Muhammad Aldi Zein, Wahed Febbry Andriansyah Ali Aug 2024

Optimization Of Bioethanol Production Using An Enzymatic Hydrolysis Process With Green Algae (Chaetomorpha) As The Raw Material, Teuku Maimun, Mirna Rahmah Lubis, Muhammad Aldi Zein, Wahed Febbry Andriansyah Ali

Makara Journal of Technology

Bioethanol is an alternative fuel derived from biological feedstock used to decrease the reliance on fossil fuels because of increasing energy consumption associated with population growth and increased use of oil fuels. Bioethanol production has been widely conducted using several types of algae, but the optimal conditions for the hydrolysis and fermentation processes are not explained in more detail. Therefore, this study focuses on determining the optimal conditions for hydrolysis and fermentation to maximize the bioethanol yield. This study uses optimization based on the hydrolysis time, temperature, and pH to increase the reducing sugar content using high-performance liquid chromatography in …


Environmental Impacts Potential Of Natural Gas Production Through Life Cycle Assessment, Akmal Al Afghani, Mochamad Adhiraga Pratama, Astryd Viandila Dahlan Aug 2024

Environmental Impacts Potential Of Natural Gas Production Through Life Cycle Assessment, Akmal Al Afghani, Mochamad Adhiraga Pratama, Astryd Viandila Dahlan

Journal of Materials Exploration and Findings

Life cycle assessment (LCA) is a methodology used to evaluate potential environmental impacts in various industry sectors, including the oil and gas industry to quantify the environmental impacts and determine the processes that have significant impacts along their production cycle. This environmental impact study adheres to ISO 14040:2016 and 14044:2017 standards, using the ReCiPe methodology within a gate-to-gate scope to analyze potential environmental impacts of 1 MMSCFD natural gas production. The impact categories analyzed in this study are Global Warming Potential (GWP), Particulate Matter Formation (PM), Ozone Formation (OF), and Terrestrial Acidification (TA). The results of this study identified several …


Inspection Planning Of Subsea Pipeline Using Risk-Based Inspection, Ni Luh Triska Adelia, Badrul Munir, Johny Wahyuadi Soedarsono Aug 2024

Inspection Planning Of Subsea Pipeline Using Risk-Based Inspection, Ni Luh Triska Adelia, Badrul Munir, Johny Wahyuadi Soedarsono

Journal of Materials Exploration and Findings

Pipelines are an important tool in oil and gas exploration. Pipeline is a transmission and liquid collection lines, including their accessories, which transport fluids from one plant to another. In transmission and collection process, there is a possibility of failure which can have minor to major impact on personnel injury, the environment and interrupt the business process. To maintain safety and to prevent accidents, the source and cause of failure needs to be calculated. Risk-based inspection (RBI) is a method that can be used to calculate the risk and determine the inspection planning both schedule and method, by combining the …


Optimizing The Expression Of Polyethylene Terephtalate Hydrolase-Encoding Synthetic Gene In Escherichia Coli Arctic Express (De3), Jocelyn Nataniel, Maria Ulfah, Dini Achnafani, Niknik Nurhayati, Gabriela Christy Sabbathini, Sri Rezeki Wulandari, Abinawanto Abinawanto, Is Helianti Jun 2024

Optimizing The Expression Of Polyethylene Terephtalate Hydrolase-Encoding Synthetic Gene In Escherichia Coli Arctic Express (De3), Jocelyn Nataniel, Maria Ulfah, Dini Achnafani, Niknik Nurhayati, Gabriela Christy Sabbathini, Sri Rezeki Wulandari, Abinawanto Abinawanto, Is Helianti

Makara Journal of Science

The waste of polyethylene terephthalate (PET) plastic waste in Indonesia is a pressing concern due to its slow degradation and potential environmental damage. One promising solution is to utilize polyethylene terephthalate hydrolase from Ideonella sakaiensis (IsPETase), an enzyme that specifically degrades PET. However, inducing the expression of IsPETase synthetic gene in Escherichia coli BL21 (DE3) has been challenging because much of it remains insoluble. This study aimed to express IsPETase in E. coli Arctic Express (DE3) and optimize the conditions to enhance its production. First, pET22b(+)pelB-IsPETase was inserted into E. coli Arctic Express (DE3). The …


Preparation Of Β-Ni (Oh)2 Nanosheet–Modified Glassy Carbon For Pseudocapacitors, Muhammad Buchari Setia Putra, Aliyah Aliyah, Afiten Rahmin Sanjaya, Respati Kevin Pramadewandaru, Hoeil Chung, Tribidasari Anggraningrum Ivandini Jun 2024

Preparation Of Β-Ni (Oh)2 Nanosheet–Modified Glassy Carbon For Pseudocapacitors, Muhammad Buchari Setia Putra, Aliyah Aliyah, Afiten Rahmin Sanjaya, Respati Kevin Pramadewandaru, Hoeil Chung, Tribidasari Anggraningrum Ivandini

Makara Journal of Science

β-Nickel hydroxide (Ni(OH)2) nanosheet–modified glassy carbon for pseudocapacitors was successfully prepared. The nanosheets were synthesized via a conventional growth seeding method combined with hydrothermal treatment. Transmission electron microscopy (TEM) characterization indicated the hexagonal structure of the nanosheets of around 15 nm in size, and X-ray diffraction (XRD) pattern confirmed the β-phase lattice crystal. These nanosheets used to modify the glassy carbon surface, increased the electroactive surface area by around 15 times. Furthermore, electrochemical investigation of the modified glassy carbon revealed an excellent performance and a specific capacitance of 628.01 F g−1 at a 1 A g−1 …


Analysis Of The Effect Of Different Surface Preparation Methods On Corrosion Resistance And Adhesion Strength Of Astm A36 Steel Substrate With Surface Tolerant Epoxy Paint As Coating Material, Irwan Wijaya Santoso, Daffa Aqila, Rini Riastuti, Rizal Tresna Ramadhani May 2024

Analysis Of The Effect Of Different Surface Preparation Methods On Corrosion Resistance And Adhesion Strength Of Astm A36 Steel Substrate With Surface Tolerant Epoxy Paint As Coating Material, Irwan Wijaya Santoso, Daffa Aqila, Rini Riastuti, Rizal Tresna Ramadhani

Journal of Materials Exploration and Findings

In the industrial world, to extend the service life of materials, protection methods are carried out to slow down the material's corrosion rate. The protection method that is often used is the coating method. The coating method is a protection method by coating the substrate material using a coating material to prevent contact between the substrate material and the environment. In this research, the substrate material used is ASTM A36 steel and the coating material used is Surface Tolerant Epoxy paint. The independent variable used in this study lies in the surface preparation method which consists of: solvent cleaning, hand …


Isolation And Characterization Of Caffeine-Degrading Bacteria From Coffee Plantation Areas In Malaysia, Elvina Clarie Dullah, Mohd Fazli Farida Asras Dec 2023

Isolation And Characterization Of Caffeine-Degrading Bacteria From Coffee Plantation Areas In Malaysia, Elvina Clarie Dullah, Mohd Fazli Farida Asras

Makara Journal of Technology

Decaffeination by microbial degradation is currently the most optimal and low-cost approach, involving only microbial cells and/or their enzymes. The bacterium was characterized using a series of biochemical tests. Positive results were obtained from carbohydrate fermentation, citrate utilization, and catalase tests, while negative results were obtained from Voges-Proskauer (VP) and indole tests. Three different caffeine concentrations of 0.25%, 0.4%, and 2% were tested and measured through Gas Chromatography-Mass Spectrophotometry (GC-MS) analysis. The highest caffeine reduction (89.25%) was found when 0.25% caffeine was used in the media. Only a small amount of caffeine was reduced to 0.4% and 2%, with 34.78% …


Combined Risk Based Inspection And Fault Tree Analysis For Repetitive 3-Phase Line Piping Leakage At West Java Offshore Topside Facility, Dona Yuliati, Akhmad Herman Yuwono, D. Rizal Asral, Donanta Dhaneswara Dec 2023

Combined Risk Based Inspection And Fault Tree Analysis For Repetitive 3-Phase Line Piping Leakage At West Java Offshore Topside Facility, Dona Yuliati, Akhmad Herman Yuwono, D. Rizal Asral, Donanta Dhaneswara

Journal of Materials Exploration and Findings

Hydrocarbon releases might result in serious consequences in various aspects. In addition to the contribution to environmental pollution, repetitive leakages need high repair costs. This study aim is to minimize potential repetitive leakage for other typical 3-phase piping systems. We conducted the risk assessment by adopting Risk Based Inspection (RBI) API 581 to identify risk level, calculating piping lifetime, recommended inspection plan and mitigations. The most relevant root causes can be obtained through quantitative Fault Tree Analysis (FTA). Observation and investigation was taken from eight 3-phase piping systems that experienced repetitive leakages. It has been found that the risk level …


Nitrogen Gas Quenching Pressure Effect On Bs S155 Alloy Steel In Vacuum Furnace, Agus Mulyadi Hasanudin, Eddy Sumarno Siradj Dec 2023

Nitrogen Gas Quenching Pressure Effect On Bs S155 Alloy Steel In Vacuum Furnace, Agus Mulyadi Hasanudin, Eddy Sumarno Siradj

Journal of Materials Exploration and Findings

The production of metal and alloy products requires the use of heat treatment, when during the heat treatment process, quenching is a crucial step. The quenching medium can be anything from water, a salt bath, oil, air and gas. In a vacuum furnace, pressurized gas, most frequently nitrogen (N2) gas, serves as one of the quenching mediums. One of the drawbacks of the quenching process is the distortion and dimensional change of the parts. This paper aims to investigate the influence of nitrogen gas quenching pressure on the distortion and dimensional change of aerospace actuator gear planet parts …


Optimization Of The Building Envelope And Roof Shading To Reduce The Energy Consumption Of College Low-Rise Buildings In Indonesia, Nasruddin Nasruddin, Azimil Gani Alam, Mohammad Imroz Sohel Dec 2023

Optimization Of The Building Envelope And Roof Shading To Reduce The Energy Consumption Of College Low-Rise Buildings In Indonesia, Nasruddin Nasruddin, Azimil Gani Alam, Mohammad Imroz Sohel

Makara Journal of Technology

Energy consumption in buildings is a crucial concern globally, prompting researchers to explore innovative solutions to mitigate its impact. This study investigates the optimization of building envelopes and roof shading systems of existing buildings in Indonesia to realize notable energy savings. Multiple scenarios were explored, with modifications to building envelopes and roof shading, highlighting the overall thermal transfer value as a key parameter. Using EnergyPlus simulations, the efficacy of natural ventilation in corridors and roof shading modifications was assessed in reducing energy consumption. The findings revealed that renovating existing buildings by optimization of the building envelope and roof shading by …


Effect Of Temperature And Steam-To-Carbon Monoxide (Co) Ratio On Hydrogen Production In Water-Gas Shift Reaction Using Cu-Zno-Al2o3 Catalyst, Sekar Kumala Desi, Restu Siti Nursa'adah, Hana Nabila Anindita, Bambang Muharto, Nurdiah Rahmawati, Tyas Puspita Rini, Erlan Rosyadi Dec 2023

Effect Of Temperature And Steam-To-Carbon Monoxide (Co) Ratio On Hydrogen Production In Water-Gas Shift Reaction Using Cu-Zno-Al2o3 Catalyst, Sekar Kumala Desi, Restu Siti Nursa'adah, Hana Nabila Anindita, Bambang Muharto, Nurdiah Rahmawati, Tyas Puspita Rini, Erlan Rosyadi

Makara Journal of Science

This study investigates the effect of steam-to-CO molar ratio and temperature on hydrogen production in a water gas shift reaction using a Cu-ZnO-Al2O3 catalyst. Herein, different steam-to-CO molar ratios (1:1, 2:1, and 3:1) and temperatures (200 °C, 250 °C, and 300 °C) were applied to investigate their impact on the reaction and H2 production. The Cu-ZnO-Al2O3 catalyst was characterized by its surface area, pore size distribution, and chemical composition. Moreover, the experimental setup enabled the control of temperature and steam-to-CO molar ratio while monitoring the product gas composition. The results revealed a considerable …


Challenges In Optimization For The Performance On Sustainability Dimensions In Reverse Logistics Social Responsibility, Sumarsono Sudarto, Katsuhiko Takahashi, Mochammad Dewo Aug 2023

Challenges In Optimization For The Performance On Sustainability Dimensions In Reverse Logistics Social Responsibility, Sumarsono Sudarto, Katsuhiko Takahashi, Mochammad Dewo

Makara Journal of Technology

Reverse logistics social responsibility is preferred as the most acceptable solution for addressing the challenges in stakeholders’ debate regarding social responsibility in supply chains because it involves as many actors as possible in the supply chain to perform social responsibility to achieve sustainability. This paper explores the challenges in achieving optimal policies in sustainability dimensions for collection and recycling facilities in reverse logistics. Sustainability dimensions include economic, environmental, and social aspects. The reverse logistics is modeled on System Dynamics, and a simplified statistical analysis using a contour chart is employed in numerical experiments. Results show a narrow area of optimal …


The Effect Of Heat Treatment And Chemical Treatment On Natural Fibre To The Durability Of Wood Plastic Composites – A Review, Nuratiqah Asyiqin Mohd Nasharudin, Nur Fatihah Sulaiman, Nurul Aziemah Mohammad, Wan Nor Raihan Wan Jaafar, Falah Abu Dr., Siti Norasmah Surip Jul 2023

The Effect Of Heat Treatment And Chemical Treatment On Natural Fibre To The Durability Of Wood Plastic Composites – A Review, Nuratiqah Asyiqin Mohd Nasharudin, Nur Fatihah Sulaiman, Nurul Aziemah Mohammad, Wan Nor Raihan Wan Jaafar, Falah Abu Dr., Siti Norasmah Surip

Journal of Materials Exploration and Findings

The application of WPC is not only limited to indoor applications but has been extended to exterior applications where properties of WPC could compromise during service life. WPC was derived from wood fiber of various sizes to reinforce polymers. Wood fiber has the advantage of a cheaper price, being abundantly available, and ease of processing, however, the critical factor is its hydrophilic nature, where moisture absorption is likely to occur. Thus, treatments for reducing the hydrophilicity of wood fibers are applied. By treatment of wood fiber, the surface impurities were removed, leaving the roughened surface of fibers, thus providing a …


Enhancing Compatibility And Mechanical Properties Of Natural Rubber Composites, Krisma Yessi Sianturi, Adam Febriyanto Nugraha, Belle Kristaura, Mochamad Chalid May 2023

Enhancing Compatibility And Mechanical Properties Of Natural Rubber Composites, Krisma Yessi Sianturi, Adam Febriyanto Nugraha, Belle Kristaura, Mochamad Chalid

Journal of Materials Exploration and Findings

Pure natural rubber (NR) exhibits low mechanical properties, necessitating the incorporation of additives like vulcanizing agents and fillers. Carbon black and silica, conventional fillers, are relatively expensive and not environmentally friendly. This study explores using Oil Palm Empty Fruit Bunch (OPEFB) fiber as an affordable, abundant, and biodegradable alternative filler for NR. However, compatibility issues arise between the nonpolar NR and the polar OPEFB fiber. A latex-starch hybrid coupling agent (CA (NR-St)) was added to the composite formulation to address this. NR, OPEFB fiber, and the coupling agent were mixed using an open roll mill with a 10 phr OPEFB …


Removal Of Hexavalent Chromium From Water By Chitosan-Enhanced Ultrafiltration, Putu A. Y. Indiasih, Anindita D. Syaifudin, Nurul Faiqotul Himma, Bambang Ismuyanto Apr 2023

Removal Of Hexavalent Chromium From Water By Chitosan-Enhanced Ultrafiltration, Putu A. Y. Indiasih, Anindita D. Syaifudin, Nurul Faiqotul Himma, Bambang Ismuyanto

Makara Journal of Technology

Polymer-enhanced ultrafiltration has gained increasing attention as a selective separation process to remove small solutes, such as metal ions, from water or wastewater. Hexavalent chromium Cr(VI) is one of the metal ions in wastewater that has received considerable attention because of its toxicity. Chitosan was used in this study as the polymer to bind Cr(VI) to enhance its removal by ultrafiltration. The effects of chitosan-to-Cr(VI) ratio on Cr(VI) rejection and permeate flux were investigated. In addition, the fouling tendency was evaluated. Results showed that the addition of chitosan with a mass ratio of 12.5 increased the Cr (VI) rejection from …


Development Of Battery Materials To Function As Corrosion Protection On Car Body Plates, Tubagus Noor Rohmannudin, Sulistijono Sulistijono, Noval Adrinanda, Faridz Wira Dharma, Samuel Areliano Jan 2023

Development Of Battery Materials To Function As Corrosion Protection On Car Body Plates, Tubagus Noor Rohmannudin, Sulistijono Sulistijono, Noval Adrinanda, Faridz Wira Dharma, Samuel Areliano

Journal of Materials Exploration and Findings

Most car bodies made for mass production are made from steel or aluminum. Both are strong metals, but steel is cheaper than aluminum and is more commonly used in lower-end cars for a broader consumer range. The weakness of steel compared to aluminum is that it is susceptible to corrosion under certain conditions, and thus it may deteriorate over time without proper care. To prevent corrosion, modern cars are coated with paint to prevent direct contact with the environment. As a second line of protection, a car battery can be connected to the body to create an impressed current cathodic …


Potential Of Biduri Fiber (Calotropis Gigantea) As Material For Oil Spill Absorbent, Anne Sukmawati, Wulan Septiani Jan 2023

Potential Of Biduri Fiber (Calotropis Gigantea) As Material For Oil Spill Absorbent, Anne Sukmawati, Wulan Septiani

Journal of Materials Exploration and Findings

Biduri fiber (Calotropis gigantea) is a natural hollow fiber with hydrophobic and oleophilic properties potentially used as oil spilled sorbent from seawater. This study aims to determine the absorption capacity and efficiency of the Biduri fiber and membrane to fuel oil. Measurement of oil absorption to seawater was carried out at various fiber weights (0.5-1.5 g), fiber composition (50-95%), contact time (10-90 minutes), temperature (30 and 50°C), and compared with commercial products. The results showed that the fiber weight variation of 0.5-1.5 g has an average absorption efficiency of 96.67%, and the highest absorption was obtained in a weight of …


A Comparison Of Techniques Of Boron Removal From Water And Wastewater, Abdolmajid Fadaei Dec 2022

A Comparison Of Techniques Of Boron Removal From Water And Wastewater, Abdolmajid Fadaei

Journal of Environmental Science and Sustainable Development

Boron is a vital trace element required by plants, humans, and animals. It is also a significant element used in several industries. Along with the widespread usage of boron, boron waste progressively contaminates the potable water sources as well as causing a chain of environmental and health challenges to occur. This study reviews the techniques used for boron removal from aqueous solutions, including ion exchange, resin adsorption, reverse osmosis (RO), electrocoagulation, microfiltration, chemical coagulation, solvent extraction, electro dialytic, and hybrid processes. A review search was carried out from the databases Scopus, PubMed, Web of Knowledge, and Embase using the following …


Damage Stability Study Of A 500 Dw Ro-Ro Ferry Vessel, Zulfaidah Ariany, Budhi Santoso, Sarwoko Sarwoko, Nauval Abdurrahman Prasetyo Dec 2022

Damage Stability Study Of A 500 Dw Ro-Ro Ferry Vessel, Zulfaidah Ariany, Budhi Santoso, Sarwoko Sarwoko, Nauval Abdurrahman Prasetyo

Makara Journal of Technology

The development of the crossing transportation industry is currently increasing in the island areas. The use of Ro-Ro type ferry boats is extremely efficient in moving people, goods, and vehicles. The current research focuses on the damage stability of the 500 DWT Ro-Ro ferry, which aims to meet the needs of the Ro-Ro ferry in the archipelago area. The previously existing initial design of a barge hull with a main size Lpp = 40.15 m, B = 12 m, H = 3.2 m, and T = 2.15 m was used to analyze the damage stability condition further. First, the drawings …


Utilization Of Biopertalite For Fuel Efficiency And Reduction In Co And Co2 Gas Emissions In Four-Wheel Motor Vehicles, Ridwan Iskandar, Hadiyanto Hadiyanto, Suherman Suherman, Zainul Akmar Zakaria Dec 2022

Utilization Of Biopertalite For Fuel Efficiency And Reduction In Co And Co2 Gas Emissions In Four-Wheel Motor Vehicles, Ridwan Iskandar, Hadiyanto Hadiyanto, Suherman Suherman, Zainul Akmar Zakaria

Makara Journal of Technology

Emissions of carbon monoxide (CO) and carbon dioxide (CO2) gases are the main problem that must be rectified as they are harmful and contribute to global warming through the greenhouse gas effect. In Indonesia, motor vehicles, especially four wheelers, are one of the biggest contributors with up to 71 million tons of CO2 emissions and energy consumption of 179 million barrel of oil equivalent. Bioethanol has octane rating >100, which is higher than that of gasoline; and emission contribution of only 0.02 kg/L, which is lower than that from gasoline (2.23 kg/L). Accordingly, a mixture of gasoline and bioethanol is …


Estimation Of The Bubble Point Pressure Of Multicomponent Reservoir Hydrocarbon Fluids, Benjamin Sunday Usen, Chidi Obi Sep 2022

Estimation Of The Bubble Point Pressure Of Multicomponent Reservoir Hydrocarbon Fluids, Benjamin Sunday Usen, Chidi Obi

Makara Journal of Science

This study developed a novel C-sharp (C#) programming language for the estimation of bubble point pressure (BPP) of various hydrocarbon mixtures at equilibrium state. The methodology was based on vapor–liquid equilibrium calculation using Peng Robinson equation of state implementation, thermodynamic equilibrium calculation and Newton-Raphson’s method for the successive substitution of the unknown variables. The equal fugacity constraint can be satisfied by obtaining the equilibrium which serves as a criterion for two or more phases to exist at equilibrium. The problem was resolved by searching for a pressure that will satisfy the two constraints. Complex calculation was performed by successively substituting …


Evaluation Of Material Request Order To Support Sustainable Construction, Fajar Susilowati, Nur Nahdiah Anggraeni Aug 2022

Evaluation Of Material Request Order To Support Sustainable Construction, Fajar Susilowati, Nur Nahdiah Anggraeni

Makara Journal of Technology

This study was conducted on one of Indonesia’s apartment projects, in which reinforced concrete is the main structure. Based on existing project data, this project experienced a decline in the construction work’s progress, thus reducing the project’s overall progress. This decline occurred because the delivery of concrete reinforcement material was delayed. This study aimed to determine the process of material request order and its relationship with the work implementation, as well as the factors that influenced the delayed arrival of concrete reinforcement material at the project site. The method used in this study was observation and interview. Data were analyzed …


Contents, Jaka Fajar Fatriansyah Aug 2022

Contents, Jaka Fajar Fatriansyah

Journal of Materials Exploration and Findings

No abstract provided.


Preface Of Volume 1 Issue 1 On Journal Of Materials Exploration And Findings (Jmef), Jaka Fajar Fatriansyah Aug 2022

Preface Of Volume 1 Issue 1 On Journal Of Materials Exploration And Findings (Jmef), Jaka Fajar Fatriansyah

Journal of Materials Exploration and Findings

No abstract provided.