Improvement Of Quality Of Carica Papaya L. With Clove Oil As Preservative In Edible Coating Technology,
2015
Department of Chemical Engineering, Universitas Indonesia, Depok 16424, Indonesia
Improvement Of Quality Of Carica Papaya L. With Clove Oil As Preservative In Edible Coating Technology, Eny Kusrini, Anwar Usman, Chrispine Deksita Wisakanti, Rita Arbianti, Dedy Alharis Nasution
Makara Journal of Technology
We have studied utilization of essential clove oil, extracted from clove buds by hydrodistillation, as preservative in edible packaging technology. Preservative of essential clove oil was applied on chopped papaya fruits by using two methods, namely spray and brush. The effects of concentration of clove oil from 0.05 to 0.20% on the preservation of papaya fruits (Carica papaya L.) at room temperature (25 °C) were also evaluated. Physicochemical and in vitro microbiological activities on the papaya fruits that were stored at 25 oC and 85-90% relative humidity were investigated in details. The results indicate that the clove oil at concentration …
Calibration Of Numerical Model For Shoreline Change Prediction Using Satellite Imagery Data,
2015
Department of Civil Engineering, Universitas Riau, Pekanbaru 28293, Indonesia
Calibration Of Numerical Model For Shoreline Change Prediction Using Satellite Imagery Data, Sigit Sutikno, Keisuke Murakami, Dwi Puspo Handoyo, Manyuk Fauzi
Makara Journal of Technology
This paper presents a method for calibration of numerical model for shoreline change prediction using satellite imagery data in muddy beach. Tanjung Motong beach, a muddy beach that is suffered high abrasion in Rangsang Island, Riau province, Indonesia was picked as study area. The primary numerical modeling tool used in this research was GENESIS (GENEralized Model for Simulating Shoreline change), which has been successfully applied in many case studies of shoreline change phenomena on a sandy beach.The model was calibrated using two extracted coastlines satellite imagery data, such as Landsat-5 TM and Landsat-8 OLI/TIRS. The extracted coastline data were analyzed …
Oxidation Process Of H 2 O /Uv For Cod Reduction Of Wastewater From Soybean Tofu Production,
2015
Department of Chemical Engineering, Faculty of Engineering, Universitas Syiah Kuala Darussalam, Banda Aceh 23111, Indonesia
Oxidation Process Of H 2 O /Uv For Cod Reduction Of Wastewater From Soybean Tofu Production, Komala Pontas, Abrar Muslim
Makara Journal of Technology
Chemical Oxygen Demand (COD) reduction of wastewater from soybean tofu production was studied by conducting advanced oxidation process (AOP) using hydrogen peroxide with UV radiation catalysts in a closed cylindrical glass reactor. The hydroxyl radical (*OH) concentration from H2O2 decomposition was modeled, and exponential trends were found for the *OH concentration over radiation time and operation temperature. As a result, it was found that the maximal *OH concentration was 0.209 mol L-1 at 240 minutes and 50 °C. The *OH concentration exponentially increased following rise in operation temperature. The H2O2/UV AOP application reduced COD concentration to approximately 42.41% from 10,545 …
Uplift Of Shoreline Regions On Pagai Island Due To The September 12, 2007 Mw 8.4 Earthquake Captured By Sar Image,
2015
Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Bengkulu, Bengkulu 38371, Indonesia
Uplift Of Shoreline Regions On Pagai Island Due To The September 12, 2007 Mw 8.4 Earthquake Captured By Sar Image, Ashar Muda Lubis
Makara Journal of Technology
At least 25 people were killed by the September 12, 2007 Mw 8.4 Bengkulu earthquake, and many buildings were destroyed in Bengkulu and West Sumatra provinces. It is very important to estimate the earth surface deformation due to the earthquake to understand the rupture size and its process. The aim of this research is to estimate the shoreline change and vertical displacement on Pagai Island associated with the September 12, 2007 Mw 8.4 Bengkulu earthquake. The intensity of ALOS-PALSAR satellite images is used to access the pattern of displacement. The result shows that Pagai Island demonstrated huge uplift due to …
Effect Of Fly Ash Fortification In The Manufacture Process Of Making Concrete Towards Characteristics Of Concrete In Sulfuric Acid Solution,
2015
Department of Chemical Engineering, Faculty of Engineering, Universitas Indonesia, Depok 16424, Indonesia
Effect Of Fly Ash Fortification In The Manufacture Process Of Making Concrete Towards Characteristics Of Concrete In Sulfuric Acid Solution, Asep Handaya Saputra, Muhammad Shohibi, Masatoshi Kubouchi
Makara Journal of Technology
Fly ash is a silica or alumino silica material that can be used as a constituent of cement in the concrete manufacturing process. Utilization of fly ash aims to improve durability and minimize the reduction of concrete’s compressive strength exposed to an acidic environment, which can be achieved through the pozzolanic reaction of fly ash with Ca(OH)2 within concrete. The reduced content of Ca(OH)2 through pozzolanic reaction will minimize the tendency of ettringite formation (compounds that cause deterioration and decrease the compressive strength of concrete). In order to determine the relation between fly ash replenishment into concrete with concrete’s characteristics …
Independency Of Elasticity On Residual Stress Of Room Temperature Rolled Stainless Steel 304 Plates For Structure Materials,
2015
Center for Science and Technology of Advance Materials, National Nuclear Energy Agency, Banten 15314, Indonesia
Independency Of Elasticity On Residual Stress Of Room Temperature Rolled Stainless Steel 304 Plates For Structure Materials, Parikin Parikin, David Allen
Makara Journal of Technology
Mechanical strengths of materials are widely expected in general constructions of any building. These properties depend on its formation (cold/hot forming) during fabrication. This research was carried out on cold-rolled stainless steel (SS) 304 plates, which were deformed to 0, 34, 84, and 152% reduction in thickness. The tests were conducted using Vickers method. Ultra micro indentation system (UMIS) 2000 was used to determine the mechanical properties of the material, i.e.: hardness, modulus elasticity, and residual stresses. The microstructures showed lengthening outcropping due to stress corrosion cracking for all specimens. It was found that the tensile residual stress in a …
Structure And Corrosion Behavior Of Sputter Deposited Cerium Oxide Based Coatings With Various Thickness On Al 2024-T3 Alloy Substrates,
2015
Missouri University of Science and Technology
Structure And Corrosion Behavior Of Sputter Deposited Cerium Oxide Based Coatings With Various Thickness On Al 2024-T3 Alloy Substrates, Yuanyuan Liu, Jiamu Huang, James B. Claypool, Carlos E. Castano, Matthew J. O'Keefe
Materials Science and Engineering Faculty Research & Creative Works
Cerium oxide-based coatings from ∼100 to ∼1400 nm in thickness were deposited onto Al 2024-T3 alloy substrates by magnetron sputtering of a 99.99% pure CeO2 target. The crystallite size of CeO2 coatings increased from 15 nm to 46 nm as the coating thickness increased from ∼100 nm to ∼1400 nm. The inhomogeneous lattice strain increased from 0.36% to 0.91% for the ∼100 nm to ∼900 nm thick coatings and slightly decreased to 0.89% for the ∼1400 nm thick coating. The highest adhesion strength to Al alloy substrates was for the ∼210 nm thick coating, due to a continuous …
Environmental Degradation Of Nickel-Based Superalloys Due To Gypsiferous Desert Dusts,
2015
Air Force Institute of Technology
Environmental Degradation Of Nickel-Based Superalloys Due To Gypsiferous Desert Dusts, Matthew B. Krisak
Theses and Dissertations
More than twenty-five years of continuous operation in the dusty environments of Southwest Asia have shown that degradation of gas turbine engine components due to particle ingestion is a serious threat to operations. In particular, the continued push for higher engine operating temperatures has brought a new emphasis to the damage mechanisms (for example CMAS glass formation and hot corrosion) caused by ingested particles forming molten deposits on engine components. Despite decades of research little progress has been made to mitigate the effects of CMAS and hot corrosion degradation to engine components. This research focused on hot corrosion specifically. A …
Laser Metal Deposition Of Functionally Gradient Materials From Elemental Copper And Nickel Powders,
2015
Missouri University of Science and Technology
Laser Metal Deposition Of Functionally Gradient Materials From Elemental Copper And Nickel Powders, Sreekar Karnati, Todd E. Sparks, Frank W. Liou, Joseph William Newkirk, Karen M. Brown Taminger, William J. Seufzer
Mechanical and Aerospace Engineering Faculty Research & Creative Works
This work deals with the planning and fabrication of a functionally gradient copper-nickel composition via Laser Metal Deposition (LMD). Various compositions of copper and nickel were made by blending different weight percentages which were then sequentially deposited to fabricate functionally gradient copper-nickel thin-wall structures. Analyses were performed by sectioning the thin-wall samples for metallographic, hardness, X-ray diffraction (XRD) and Energy Dispersive X-ray Spectroscopy (EDS) studies. The fabrication was studied for identifying and corroborating the deposited compositions and their corresponding gradients. XRD analyses were performed to identify the crystal structure of the deposit. EDS analysis was instrumental in identifying the variation …
Application Of Fiscal Incentives For Development Of East Natuna Gas Field For Long-Term National Natural Gas Demand,
2015
Department of Chemical Engineering, Faculty of Engineering, Universitas Indonesia, Depok 16424, Indonesia
Application Of Fiscal Incentives For Development Of East Natuna Gas Field For Long-Term National Natural Gas Demand, Marwan Batubara, Widodo Wahyu Purwanto, Akhmad Fauzi
Makara Journal of Technology
East Natuna gas field, which has proven reserves of 46 trillion cubic feet, is projected to meet long-term natural gas needs. However, CO2-content of the gas reserves reaches 71%, leading to expensive development costs. This research investigates the feasibility of the field based on several fiscal incentives. Firstly, gas supply-demand until year 2040 was analyzed. Then, based on the analysis, the field was developed using high CO2 gas separation technology to produce gas of 1300 MMSCFD in 2023, 2600 MMSCFD in 2031, and 3900 MMSCFD in 2039. Finally, the economic feasibility was assessed using cash flow analysis in accordance with …
High Temperature Corrosion Of Aluminized Aisi 4130 Steel With The Different Composition Of Nacl/Na2so4 Deposits,
2015
Department of Mechanical Engineering, Faculty of Engineering, Universitas Lampung, Bandar Lampung 35145, Indonesia
High Temperature Corrosion Of Aluminized Aisi 4130 Steel With The Different Composition Of Nacl/Na2so4 Deposits, Mohammad Badaruddin, Chaur Jeng Wang, Yudhistyra Saputra, Abu Khalid Rivai
Makara Journal of Technology
The high temperature corrosion of AISI 4130 steel can be increased by hot-dip aluminizing coating. The aluminized steel specimens with the deposit composition of 100/0, 30/70, 50/50, 70/30, and 0/100 (wt.%) NaCl/Na2SO4 were oxidized at 750 °C for 1-49 h periods. According to a parabolic rate constant (kp) value, the aluminized steel with deposit composition of 70/30 NaCl/Na2SO4 shows the highest kp value (3.71 × 10-11 g2cm- 4s-1), later followed by the kp value of 3.35 × 10-11 g2cm-4s-1 for 100/0 and the lowest kp value is 7.731 × 10-12 g2cm-4s-1 for 0/100. Whereas, the kp value for the aluminized …
Thermodynamic Analysis Of Irreversible Heat-Transformers,
2015
Department of Applied Mechanics and Aerospace Engineering, Waseda University, 3-4-1 Okubo, 4 Shinjuku-ku, Tokyo 169-8555, Japan
Thermodynamic Analysis Of Irreversible Heat-Transformers, Niccolo` Giannetti, Arnas Arnas, Andrea Rocchetti, Kiyoshi Saito
Makara Journal of Technology
Absorption heat transformers extend the possibilities for efficient and environment-friendly energy conversion processes. Based on a general thermodynamic model of three-thermal cycles with finite thermal capacity of the heat sources, this paper is intent upon analyzing and optimizing the performance of absorption heat transformers, by including the influence of irreversibility in the analytical expression of the system efficiency. Dimensionless parameters for an overall optimization are defined and a first screening is performed to clarify their influence. Dependence on the main factors is highlighted to suggest how to change them in order to enhance the whole system performance. Under this point …
Transmission Electron Microscopy Characterization Of High-Temperatur Oxidation Of Fe-20cr-5al Alloy Prepared By Focused Ion Beam Technique,
2015
Center for Science and Technology of Advanced Materials – National Nuclear Energy Agency (PSTBM-BATAN) PUSPIPTEK Serpong, Tangerang 15314, Indonesia
Transmission Electron Microscopy Characterization Of High-Temperatur Oxidation Of Fe-20cr-5al Alloy Prepared By Focused Ion Beam Technique, Mohammad Dani, Pudji Untoro, Teguh Yulius Surya Panca Putra, Parikin Parikin, Joachim Mayer, Arbi Dimyati
Makara Journal of Technology
The Focused Ion Beam (FIB) technique was applied for cross section preparation of the oxidized alloy for Transmission Electron Microscopy (TEM) study. Prior to preparation, the specimens of Fe-20Cr-5Al alloy sheet were oxidized in air at 1200 oC for 2 minutes, 10 minutes, 2 hours, and 100 hours. The microstructure and elemental composition of the samples were characterized using TEM equipped with an Energy Dispersive X-Ray Spectroscopy (EDX). The Electron Energy Loss Spectroscopy (EELS) was used to determine of the light elements. The TEM investigation reveals remarkable microstructure evolution of the specimens during oxidation which generally exhibit a typical multi-layer …
Effects Of Supplier-Manufacturer Relationships On Supply-Chain Performance Of Manufacturing Industries In Indonesia,
2015
Department of Industrial Engineering, Universitas Trunojoyo Madura, Kamal Bangkalan 69162, Indonesia
Effects Of Supplier-Manufacturer Relationships On Supply-Chain Performance Of Manufacturing Industries In Indonesia, Rachmad Hidayat, Khisbullah Hudha, Sabarudin Akhmad
Makara Journal of Technology
The present study describes the relationships between commitment, communication, satisfaction, trust, relationship quality with suppliers, and supply-chain performance. The population of the study was manufacturing companies in Indonesia. Respondents were the chief executive officers or corporate secretaries or the designated managers involved in strategic decision making. Samples were taken by using a proportional area random sampling technique. Structural Equation Modeling (SEM) was used for analysis. Results of both direct and indirect testing of hypothesis indicated two hypotheses of positive and significant effects and nine hypotheses of positive but insignificant effects. Those hypotheses of positive and significant effects were the direct …
A New Method For Simulating Power Flow Density Focused By A Silicon Lens Antenna Irradiated With Linearly Polarized Thz Wave,
2015
Graduate School of Science and Technology, Shizuoka University, 3-5-1 Johoku, Nakaku, Hamamatsu 432-8011, Japan
A New Method For Simulating Power Flow Density Focused By A Silicon Lens Antenna Irradiated With Linearly Polarized Thz Wave, Catur Apriono, Eko Tjipto Rahardjo, Norihisa Hiromoto
Makara Journal of Technology
A terahertz system uses dielectric lens antennas for focusing and collimating beams of terahertz wave radiation. Linearly polarized terahertz wave radiation has been widely applied in the terahertz system. Therefore, an accurate method for analyzing the power flow density in the dielectric lens antenna irradiated with the linearly polarized terahertz wave radiation is important to design the terahertz systems. In optics, ray-tracing method has been used to calculate the power flow density by a number density of rays. In this study, we propose a method of ray-tracing combined with Fresnel’s transmission, including transmittance and polarization of the terahertz wave radiation …
Stochastic Optimization Of Supply Chain Risk Measures –A Methodology For Improving Supply Security Of Subsidized Fuel Oil In Indonesia,
2015
Department of Chemical Engineering, Faculty of Engineering, University of Indonesia, Depok 16424, Indonesia
Stochastic Optimization Of Supply Chain Risk Measures –A Methodology For Improving Supply Security Of Subsidized Fuel Oil In Indonesia, Adinda Yuanita, Andi Noorsaman Sommeng, Anondho Wijonarko
Makara Journal of Technology
Monte Carlo simulation-based methods for stochastic optimization of risk measures is required to solve complex problems in supply security of subsidized fuel oil in Indonesia. In order to overcome constraints in distribution of subsidized fuel in Indonesia, which has the fourth largest population in the world—more than 250,000,000 people with 66.5% of productive population, and has more than 17,000 islands with its population centered around the nation's capital only—it is necessary to have a measurable and integrated risk analysis with monitoring system for the purpose of supply security of subsidized fuel. In consideration of this complex issue, uncertainty and probability …
Impurity Diffusion As A Possible Metal Chronometer For Pre-Detonation Nuclear Forensics,
2015
United States Military Academy
Impurity Diffusion As A Possible Metal Chronometer For Pre-Detonation Nuclear Forensics, Edward T. Peskie, Howard L. Hall
International Journal of Nuclear Security
The ability to determine the age of seized nuclear material—that is, the time that has passed since it was formed— would provide crucial data to be used in its investigation. This paper reviews the methods and mathematical reasoning behind the use of diffusion theory, as previously applied to analysis of metals in ancient artifacts and other objects, to modern investigations in nuclear science. We here examine the time-dependent processes of diffusion, including grain boundary diffusion and discontinuous precipitation, and we assess the utility of examining the profiles of impurity and alloying element concentrations for use as a tool in pre-detonation …
Radiation Damage As A Possible Metal Chronometer For Pre-Detonation Nuclear Forensics,
2015
United States Military Academy
Radiation Damage As A Possible Metal Chronometer For Pre-Detonation Nuclear Forensics, Edward T. Peskie, Howard L. Hall
International Journal of Nuclear Security
The better we can determine how long ago nuclear material was made, the sharper our tools for investigating seized nuclear materials. This paper examines the effects of radiation damage caused by the decay of uranium isotopes, and assesses how experts in nuclear forensics could use the analyses of these damaged regions to determine how much time has passed since metal samples were formed. It also draws parallels from fission track dating studies of mineral samples under geologic time, and proposes modifications to past publications on α-recoil track dating in order to determine the time since a metal sample was cast …
An Investigation Of Incipient Melting During Solution Heat Treatment Of 7050 Aluminum Forgings And Its Effect On Corrosion Properties,
2015
California Polytechnic State University - San Luis Obispo
An Investigation Of Incipient Melting During Solution Heat Treatment Of 7050 Aluminum Forgings And Its Effect On Corrosion Properties, Thomas Kilkenny
Materials Engineering
7050 alloy (6.2Zn-2.3Mg-2.3Cu-0.12Zr) is a structural aluminum alloy commonly used in the aerospace industry. Its rich chemistry makes it susceptible to incipient melting. Incipient melting is a phenomenon where areas with high local alloy content melt before the rest of the material. This can cause a degradation of mechanical and corrosion properties. A six by four factor solution heat treatment trial was conducted. Six solution heat treatment temperatures, 890- 940°F in 10°F increments, and four times, 1, 2, 4, and 6 hours, were used. Incipient melting was observed in the 910°F, 6 hour solution heat treatment and all 920-940°F solution …
Analysis Of Shear Strength Variance Of Ph 15-7 Mo Blind Rivet Stems For Aerospace Applications,
2015
California Polytechnic State University - San Luis Obispo
Analysis Of Shear Strength Variance Of Ph 15-7 Mo Blind Rivet Stems For Aerospace Applications, Miles Macarthur, Kent C. Majewski
Materials Engineering
This project attempts to reduce manufacturing costs incurred to Cherry Aerospace by variance in material properties. To track and predict the shear strength of PH 15-7 Mo stainless steel rivet stems throughout the heat treatment process, samples were taken from several steps in the manufacturing process and experimental heat treatments were performed across a range of temperatures. The supplied rivet stems were heat treated for four hours at temperatures from 520°C to 560°C, in increments of 10°C. Double shear testing in accordance with ASTM 1312-13A revealed that there is no apparent correlation between the strength of the supplied wire and …
