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Articles 601 - 630 of 986
Full-Text Articles in Chemical Engineering
Texture Analysis Using The Neutron Diffraction Method On The Non Standardized Austenitic Steel Process By Machining,Annealing, And Rolling, Tri Hardi Priyanto, Parikin Parikin, Meijuan Li
Texture Analysis Using The Neutron Diffraction Method On The Non Standardized Austenitic Steel Process By Machining,Annealing, And Rolling, Tri Hardi Priyanto, Parikin Parikin, Meijuan Li
Makara Journal of Technology
Austenitic steel is one type of stainless steel which is widely used in the industry. Many studies on austenitic stainless steel have been performed to determine the physical properties using various types of equipment and methods. In this study, the neutron diffraction method is used to characterize the materials which have been made from minerals extracted from the mines in Indonesia. The materials consist of a granular ferro-scrap, nickel, ferro-chrome, ferro-manganese, and ferro-silicon added with a little titanium. Characterization of the materials was carried out in three processes, namely: machining, annealing, and rolling. Experimental results obtained from the machining process …
Maneuverability Of Ships With Small Draught In Steady Wind, Daeng Paroka, Andi Haris Muhammad, Syamsul Asri
Maneuverability Of Ships With Small Draught In Steady Wind, Daeng Paroka, Andi Haris Muhammad, Syamsul Asri
Makara Journal of Technology
Wind force and moment may force a ship to drastically decrease its speed and use a large drift angle as well as a large rudder angle in order to maintain its course. Ships with a small draught might have more risk in maneuvering to its point of view compared with a ship with a larger draught. This paper discusses maneuverability of a ship with a small draught in steady wind. The effect of wind on ship speed, drift angle, and rudder angle are investigated in a steady state condition. Five different ratios of wind velocity to ship speed from 1.0 …
A Comparison Of American, Norwegian, And Russian Standards In Calculating The Wall Thickness Of Submarine Gas Pipeline, Cindy Dianita, Tatyana Vladimirovna Dmitrieva
A Comparison Of American, Norwegian, And Russian Standards In Calculating The Wall Thickness Of Submarine Gas Pipeline, Cindy Dianita, Tatyana Vladimirovna Dmitrieva
Makara Journal of Technology
One of the key issues in the pipeline design is wall thickness calculation. This paper highlights a comparison of wall thickness calculation methods of submarine gas pipeline based on Norwegian Standard (DNV-OS-F101), Indonesian Standard SNI 3474 which refers to American Standard (ASME B31.8), and Russian Standard (VN39-1.9-005-98). A calculation of wall thickness for a submarine gas pipeline in Indonesia (pressure 12 MPa, external diameter 668 mm) gives the results of 18.2 mm (VN39-1.9-005-98), 16 mm (ASME B31.8), and 13.5 mm (DNV-OS-F101).The design formula of hoop stress due to internal pressure is interpreted in different ways for every standard. Only Norwegian …
Thawing Out: The Role Of The Arctic Council Service In A Melting Arctic, Taylor J. Enos
Thawing Out: The Role Of The Arctic Council Service In A Melting Arctic, Taylor J. Enos
Pell Scholars and Senior Theses
With the changing natural and political climate of the Arctic, conflicts over resource extraction and navigation will become inevitable. Empowering an intergovernmental institution like the Arctic Council Service may be the only solution. This paper analyzes the importance and history of the Arctic as a political environment, which is prone to abuse in the very near future at the hands of Russia and the United States.
Methane Emissions As Energy Reservoir: Context, Scope, Causes And Mitigation Strategies, Xiaoli Chai, David J. Tonjes, Devinder Mahajan
Methane Emissions As Energy Reservoir: Context, Scope, Causes And Mitigation Strategies, Xiaoli Chai, David J. Tonjes, Devinder Mahajan
Technology & Society Faculty Publications
Methane (CH4) is now considered a bridge fuel between present fossil (carbon) economy and desired renewables and this energy molecule is projected to play an important role in the global energy mix well beyond 2035. The atmospheric warming potential of CH4 is 28-36 times, when averaged over a 100-year period, that of carbon dioxide (CO2) and this necessitates a close scrutiny of global CH4 emissions inventory. As the second most abundant greenhouse gas (GHG), the annual global CH4 emissions were 645 million metric tons (MMT), accounting for 14.3% of the global anthropogenic GHG emissions. Of this, five key anthropogenic sources: …
State-Of-The-Art Review Of Cathodic Protection For Reinforced Concrete Structures, Aimee Byrne, Niall Holmes, Brian Norton
State-Of-The-Art Review Of Cathodic Protection For Reinforced Concrete Structures, Aimee Byrne, Niall Holmes, Brian Norton
Articles
Cathodic protection (CP) limits the corrosion of a metal surface by making it the cathode of an electrochemical cell. This can be achieved either by using a more active sacrificial anode to create a driving current, or by using inert anodes and impressing a current onto the cathode surface using an external direct current (DC) source. Impressed current cathodic protection (ICCP) is preferred where widespread protection is required, particularly in reinforced concrete structures. ICCP needs a constant DC power supply that is usually provided through a grid connection or independent generators. This paper presents the currently available CP systems for …
Protein-Targeted Corona Phase Molecular Recognition, Gili Bisker, Juyao Dong, Hoyoung D. Park, Nicole M. Iverson, Jiyoung Ahn, Justin T. Nelson, Markita P. Landry, Sebastian Kruss, Michael S. Strano
Protein-Targeted Corona Phase Molecular Recognition, Gili Bisker, Juyao Dong, Hoyoung D. Park, Nicole M. Iverson, Jiyoung Ahn, Justin T. Nelson, Markita P. Landry, Sebastian Kruss, Michael S. Strano
Department of Agricultural and Biological Systems Engineering: Faculty Publications
Corona phase molecular recognition (CoPhMoRe) uses a heteropolymer adsorbed onto and templated by a nanoparticle surface to recognize a specific target analyte. This method has not yet been extended to macromolecular analytes, including proteins. Herein we develop a variant of a CoPhMoRe screening procedure of single-walled carbon nanotubes (SWCNT) and use it against a panel of human blood proteins, revealing a specific corona phase that recognizes fibrinogen with high selectivity. In response to fibrinogen binding, SWCNT fluorescence decreases by >80% at saturation. Sequential binding of the three fibrinogen nodules is suggested by selective fluorescence quenching by isolated sub-domains and validated …
Characterization Of Biochars Produced From Peanut Hulls And Pine Wood With Different Pyrolysis Conditions, James W. Lee, Bob Hawkins, Michelle K. Kidder, Barbara R. Evans, A. C. Buchanan, Danny Day
Characterization Of Biochars Produced From Peanut Hulls And Pine Wood With Different Pyrolysis Conditions, James W. Lee, Bob Hawkins, Michelle K. Kidder, Barbara R. Evans, A. C. Buchanan, Danny Day
Chemistry & Biochemistry Faculty Publications
Background
Application of modern biomass pyrolysis methods for production of biofuels and biochar is potentially a significant approach to enable global carbon capture and sequestration. To realize this potential, it is essential to develop methods that produce biochar with the characteristics needed for effective soil amendment.
Methods
Biochar materials were produced from peanut hulls and pine wood with different pyrolysis conditions, then characterized by cation exchange (CEC) capacity assays, nitrogen adsorption–desorption isotherm measurements, micro/nanostructural imaging, infrared spectra and elemental analyses.
Results
Under a standard assay condition of pH 8.5, the CEC values of the peanut hull-derived biochar materials, ranging from …
Cement Based Batteries And Their Potential For Use In Low Power Operations, Aimee Byrne, Niall Holmes, Brian Norton
Cement Based Batteries And Their Potential For Use In Low Power Operations, Aimee Byrne, Niall Holmes, Brian Norton
Articles
This paper presents the development of an innovative cement-electrolyte battery for low power operations such as cathodic protection of reinforced concrete. A battery design was refined by altering different constituents and examining the open circuit voltage, resistor loaded current and lifespan. The final design consisted of a copper plate cathode, aluminium plate anode, and a cement electrolyte which included additives of carbon black, plasticiser, Alum salt and Epsom salt. A relationship between age, temperature and hydration of the cell and the current it produced was determined. It was found that sealing the battery using varnish increased the moisture retention and …
An Overview Of The Development Of Cement-Based Batteries For The Cathodic Protection Of Embedded Steel In Concrete, Aimee Byrne, Niall Holmes, Brian Norton
An Overview Of The Development Of Cement-Based Batteries For The Cathodic Protection Of Embedded Steel In Concrete, Aimee Byrne, Niall Holmes, Brian Norton
Conference papers
This paper presents an overview of the cement-based batteries developed in DIT for use in the cathodic protection of embedded steel in reinforced concrete undergoing chloride-induced corrosion. Cathodic protection delivers an external current (approximately 20mA per m2 of embedded steel) which effectively polarises the internal current generated during corrosion. The batteries developed in DIT comprise of a cement-based electrolyte containing different additives including sand, aggregate, salts, carbon black and plasticiser with protruding anode and cathode metal plates. These batteries produced an initial electrical output of 1.5V and 23mA through a 10 resistor as measured using data acquisition units and a …
Improving Renewable Energy Transition Acceptance: A Simulation Gaming Approach On A Multi Actor Setting In The Netherlands, Aziiz Sutrisno, Jac A. M. Vennix, Noor Syaifudin
Improving Renewable Energy Transition Acceptance: A Simulation Gaming Approach On A Multi Actor Setting In The Netherlands, Aziiz Sutrisno, Jac A. M. Vennix, Noor Syaifudin
Makara Journal of Technology
The Netherlands have tried very hard to increase their renewable energy sources (RES) shares to fulfill the European Union target in 2050. However, RES performance did not show the expected result as the performance declined in 2009 producing even wider gap compare to the target. The Dutch government’s tried to incorporate all interested stakeholders by forming the Dutch energy transition task force. Nevertheless, the task force’s result is also not showing a desirable trend. Key reasons behind the Dutch low RES performance are the lack of shared understanding and positive attitude toward RES development among interested actors. This research uses …
Dual-Band Singly-Fed Proximity-Coupled Tip-Truncated Triangular Patch Array For Land Vehicle Mobile System, Basari Basari, Josaphat Tetuko Sri Sumantyo
Dual-Band Singly-Fed Proximity-Coupled Tip-Truncated Triangular Patch Array For Land Vehicle Mobile System, Basari Basari, Josaphat Tetuko Sri Sumantyo
Makara Journal of Technology
This paper proposes a dual-band left-handed circularly polarized triangular-patch array that is developed for land vehicle mobile system aimed at mobile satellite communications. The array consists of six tip-truncated triangular patches, which the first three patches are used for reception and the second three patches are used for transmission purpose. Each of three-patches has a beam pattern that can be switched in three different 120°-coverage beam in azimuth-cut plane at a minimum targeted gain at a desired elevation angle. The targeted minimum gain of the array is 5 dBic, in order for data communications with a large geostationary satellite can …
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
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, Sigit Sutikno, Keisuke Murakami, Dwi Puspo Handoyo, Manyuk Fauzi
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 …
Independency Of Elasticity On Residual Stress Of Room Temperature Rolled Stainless Steel 304 Plates For Structure Materials, Parikin Parikin, David Allen
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 …
Oxidation Process Of H 2 O /Uv For Cod Reduction Of Wastewater From Soybean Tofu Production, Komala Pontas, Abrar Muslim
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, Ashar Muda Lubis
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, Asep Handaya Saputra, Muhammad Shohibi, Masatoshi Kubouchi
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 …
Sustainability Assessment For Energy Systems And Chemical Process Industries, Michael J. Matzen
Sustainability Assessment For Energy Systems And Chemical Process Industries, Michael J. Matzen
Department of Chemical and Biomolecular Engineering: Dissertations, Theses, and Student Research
Sustainability has become an important factor in the chemical process and energy industries with a strong drive for process improvements towards more environmentally conscious solutions. However, there are many ways of defining sustainability and even more ways of trying to determine how sustainable a process is. This work looks into applying a conjunction of tools including; process simulation, multi-criteria decision matrices and life-cycle assessment to more quantitatively determine sustainability metrics. We have applied these tools for the production of electricity, methanol and dimethyl ether. A novel method of electricity production, in chemical looping combustion (CLC), was used that inherently involves …
Production And Harvest Of Microalgae In Wastewater Raceways With Resource Recycling, Alexander Colin Roberts
Production And Harvest Of Microalgae In Wastewater Raceways With Resource Recycling, Alexander Colin Roberts
Master's Theses
Microalgae can be grown on municipal wastewater media to both treat the wastewater and produce feedstock for algae biofuel production. However the reliability of treatment must be demonstrated, as well as high areal algae productivity on recycled wastewater media and efficient sedimentation harvesting. This processes was studied at pilot scale in the present research.
A pilot facility was operated with nine CO2-supplemented raceway ponds, each with a 33-m2 surface area and a 0.3-m depth, continuously from March 6, 2013 through September 24, 2014. The ponds were operated as three sets of triplicates with two sets continuously fed …
Feasibility Of Cathodic Protection In Grouted Post Tensioned Tendons - Exploratory Model Calculations, Jacob Dharma Bumgardner
Feasibility Of Cathodic Protection In Grouted Post Tensioned Tendons - Exploratory Model Calculations, Jacob Dharma Bumgardner
USF Tampa Graduate Theses and Dissertations
Recent corrosion related failures of grouted post tensioned tendons, even after the introduction of improved grouts, have led to renewed interest in supplemental or backup means of corrosion control for these systems. A finite element model is presented to explore feasibility of impressed current cathodic protection of strand in grouted tendons. The model examines polarization evolution as function of service time and includes consideration of anode placement and size, grout porosity, pore water alkalinity, electrochemical species diffusivity and applied voltage on the polarization efficacy and durability of such a system. The exploratory model projections suggested that, within the context of …
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
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 …
Thermodynamic Analysis Of Irreversible Heat-Transformers, Niccolo` Giannetti, Arnas Arnas, Andrea Rocchetti, Kiyoshi Saito
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 …
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
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 …
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
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 …
Effects Of Supplier-Manufacturer Relationships On Supply-Chain Performance Of Manufacturing Industries In Indonesia, Rachmad Hidayat, Khisbullah Hudha, Sabarudin Akhmad
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 …
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
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 …
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
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 …
Secondary Organic Aerosol Formation From The Β-Pinene+No3 System: Effect Of Humidity And Peroxy Radical Fate, C. M. Boyd, J. Sanchez, L. Xu, Alexis J. Eugene, T. Nah, W. Y. Tuet, Marcelo I. Guzman, N. L. Ng
Secondary Organic Aerosol Formation From The Β-Pinene+No3 System: Effect Of Humidity And Peroxy Radical Fate, C. M. Boyd, J. Sanchez, L. Xu, Alexis J. Eugene, T. Nah, W. Y. Tuet, Marcelo I. Guzman, N. L. Ng
Chemistry Faculty Publications
The formation of secondary organic aerosol (SOA) from the oxidation of β-pinene via nitrate radicals is investigated in the Georgia Tech Environmental Chamber (GTEC) facility. Aerosol yields are determined for experiments performed under both dry (relative humidity (RH) < 2 %) and humid (RH = 50 % and RH = 70 %) conditions. To probe the effects of peroxy radical (RO2) fate on aerosol formation, "RO2 + NO3 dominant" and "RO2 + HO2 dominant" experiments are performed. Gas-phase organic nitrate species (with molecular weights of 215, 229, 231, and 245 amu, which likely correspond to molecular formulas of C10H17NO4, C10H15NO5, C10H17NO …
Hydrothermal Catalytic Liquefaction And Deoxygenation Of Biomass For Renewable Fuel Production, Sergiy Popov
Hydrothermal Catalytic Liquefaction And Deoxygenation Of Biomass For Renewable Fuel Production, Sergiy Popov
Civil & Environmental Engineering Theses & Dissertations
In recent years, sub- and supercritical water technologies received an increasing attention because of the numerous advantages they offer for biomass converting into biofuels. Water at elevated temperatures and pressures provides an ideal medium for chemical transformations. It serves as a reactant, reaction medium, and catalyst that helps biomass compounds undergo hydrolysis, depolymerization, dehydration, decarboxylation, and condensation/repolymerization reactions. Biomass is the fourth largest source of energy in the world after coal, oil, and natural gas that has the potential to provide the large scale substitution of hydrocarbon-based liquid transportation fuels and minimize the environmental issues. Biomass typically contains 40-60% oxygen. …