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Articles 15931 - 15960 of 30247
Full-Text Articles in Mechanical Engineering
High Pressure Combustion And Supersonic Jet Ignition For H2/Air, Michael G. Woodworth, Sayan Biswas, Li Qiao
High Pressure Combustion And Supersonic Jet Ignition For H2/Air, Michael G. Woodworth, Sayan Biswas, Li Qiao
The Summer Undergraduate Research Fellowship (SURF) Symposium
There are many incentives to increase the fuel efficiency of combustion processes. This paper looks at two available options to achieve this goal. The former aims to develop an experimental method that can analyze combustion at extremely high pressures to improve the understanding of high pressure H2/air combustion. Experimental data has been lacking a suitable combustion diagnostic to visualize high pressure combustion processes, making it difficult to improve the process. Improvement of x-ray diffraction tomography in a windowless combustor makes it possible to see flame propagation at high pressure. The procedure and chamber are still in the design phase, yet …
Integrating Systems For Liquid/Substrate Characterization And Functional Printing, Jianyi Du, J. William Boley, Rebecca K. Kramer
Integrating Systems For Liquid/Substrate Characterization And Functional Printing, Jianyi Du, J. William Boley, Rebecca K. Kramer
The Summer Undergraduate Research Fellowship (SURF) Symposium
Gallium-Indium alloys are recently applied in fabricating soft devices, such as stretchable sensors, electric circuits, micro pumps and optics. Its printability demonstrates the possibility for a wide extension of the application. Current fabrication methods are inefficient when printing is most handled manually, and are highly dependent on material properties. There is need for a fast way to characterize material properties, and to functionally print the given shape on the substrate. This paper presents the construction of an efficiently integrated system with optical imaging and functional printing for Gallium-Indium alloys. The imaging section allows for characterization of material properties to fast …
Hot Surface Ignition, Yerbatyr Tursyn, Vikrant Goyal, Alicia Benhidjeb-Carayon, Richard Simmons, Scott Meyer, Jay P. Gore
Hot Surface Ignition, Yerbatyr Tursyn, Vikrant Goyal, Alicia Benhidjeb-Carayon, Richard Simmons, Scott Meyer, Jay P. Gore
The Summer Undergraduate Research Fellowship (SURF) Symposium
Undesirable hot surface ignition of flammable liquids is one of the hazards in ground and air transportation vehicles, which primarily occurs in the engine compartment. In order to evaluate the safety and sustainability of candidate replacement fuels with respect to hot surface ignition, a baseline low lead fuel (Avgas 100 LL) and four experimental unleaded aviation fuels recommended for reciprocating aviation engines were considered. In addition, hot surface ignition properties of the gas turbine fuels Jet-A, JP-8, and JP-5 were measured. A test apparatus capable of providing reproducible data was designed and fabricated to experimentally investigate the hot surface ignition …
3d Printing Nanostructured Thermoelectric Device, Qianru Jia, Collier Miers, Amy Marconnet
3d Printing Nanostructured Thermoelectric Device, Qianru Jia, Collier Miers, Amy Marconnet
The Summer Undergraduate Research Fellowship (SURF) Symposium
Thermoelectric materials convert thermal energy to electrical energy and vice versa. Thermoelectrics have attracted much attention and research efforts due to the possibility solving electronic cooling problems and reducing energy consumption through waste heat recovery. The efficiency of a thermoelectric material is determined by the dimensionless figure of merit ZT, which depends on both thermal and electrical properties. Researchers have worked for several decades to improve the ZT, but there had been little progress until nanomaterials and nanofabrication became widely available. Nanotechnology makes the ZT enhancement attainable by disconnecting the linkage between thermal and electrical transport. Printing customized, flexible thermoelectric …
Characterization Of Hydrogel Curing Methods For Manufacturability, Hannah E. Brown, Rebecca K. Kramer, Edward L. White
Characterization Of Hydrogel Curing Methods For Manufacturability, Hannah E. Brown, Rebecca K. Kramer, Edward L. White
The Summer Undergraduate Research Fellowship (SURF) Symposium
In the field of soft robotics, hydrogels possess material properties that allow them to function as both soft strain sensors and dielectric elastomer actuators. However, there is still much that needs to be understood about the curing process of hydrogels and the resulting material characteristics before manufacturing these devices can be accomplished. In this study, we investigated the effect of curing time and sample volume on the as-cured material properties of acrylamide-based hydrogels hydrated with lithium and magnesium chloride salt solutions. Samples were cured at room temperature, 60° C and 100° C, and the resulting changes in mechanical stiffness and …
Optimization In The Simulation Of Jammed Polyhedral Particles, Joseph W. Mynhier, Ishan Srivastava, Timothy S. Fisher
Optimization In The Simulation Of Jammed Polyhedral Particles, Joseph W. Mynhier, Ishan Srivastava, Timothy S. Fisher
The Summer Undergraduate Research Fellowship (SURF) Symposium
Energy loss due to poor transport properties in electrically and thermally conducting materials, such as battery electrodes and thermoelectric composites, contributes to the energy inefficiency of electronic devices. For conductive materials composed of granular materials, particle-particle contact topology strongly governs the efficiency of energy transfer. Although there is a large body of existing work on the arrangements made by granular materials comprised of spherical particles, less is known about the mechanically stable arrangements of granular materials made of convex polyhedra. This project seeks to create a computer simulation of the solidification of convex polyhedra from a diffuse state into a …
Influences Of Wind On Automotive Interior Sound Quality, Sara Huelsman, Patricia Davies, Daniel Carr
Influences Of Wind On Automotive Interior Sound Quality, Sara Huelsman, Patricia Davies, Daniel Carr
The Summer Undergraduate Research Fellowship (SURF) Symposium
The effects of noise on human health (both mental and physical) are well known, and motivation to decrease noise in daily life is prevalent. Wind noise within automotive interior cabins could be detrimental to human health and comfort because of the negative impact on speech intelligibility and fatigue overall. There is little information on human perception of wind noise in automobile interiors though Loudness and Articulation Index have been examined as predictors of human response. They have been found to predict well in some circumstances, but not in others. In this research, a variety of sound quality metrics are being …
Altered Combustion Characteristics Of Aluminum Fuels Through Low-Level Fluoropolymer Inclusions With And Without In Situ Nanoaluminum., Courtney K. Murphy, Brandon Terry, Steven F. Son
Altered Combustion Characteristics Of Aluminum Fuels Through Low-Level Fluoropolymer Inclusions With And Without In Situ Nanoaluminum., Courtney K. Murphy, Brandon Terry, Steven F. Son
The Summer Undergraduate Research Fellowship (SURF) Symposium
Aluminum inclusions have been widely used to increase the specific impulse of solid rocket propellant. However, issues arise with the addition of aluminum in the form of agglomeration, which can cause kinetic and thermal losses (i.e., two-phase flow losses) through the nozzle, which can reduce motor performance by as much as 10%. Reduction of agglomerate size may reduce the effect of two-phase flow losses. Polytetrafluoroethylene (PTFE or TeflonTM) inclusions into aluminum via mechanical activation (MA, milling) have been shown to produce a smaller coarse agglomerate size due to microexplosion of the composite particles at the propellant surface. Perflouroalkoxy …
Fracture Mechanics-Based Simulation Of Pv Module Delamination, Dominic I. Jarecki, Johanna B. Palsdottir, Peter Bermel, Marisol Koslowski
Fracture Mechanics-Based Simulation Of Pv Module Delamination, Dominic I. Jarecki, Johanna B. Palsdottir, Peter Bermel, Marisol Koslowski
The Summer Undergraduate Research Fellowship (SURF) Symposium
Photovoltaic (PV) cells are rapidly growing as a renewable alternative to fossil fuels like coal, oil, and natural gas. However, greater adoption has also reduced government subsidies, placing the onus of making solar panels economically competitive on innovative research. While multiple methods have been considered for reducing costs, with each reduction in cost comes the associated peril of reduction in quality and useful lifetime. Several problems considered solved have now resurfaced as potential failure mechanisms with the introduction of cheaper PV cell technologies. However, to remain economically viable, PV modules will not only have to become cheaper, they will have …
Towards An Optical In-Line Characterization Of Nano Petals, Yiming Ding, Huisung Kim, Euiwon Bae
Towards An Optical In-Line Characterization Of Nano Petals, Yiming Ding, Huisung Kim, Euiwon Bae
The Summer Undergraduate Research Fellowship (SURF) Symposium
Carbon Nano Petals (i.e. CNPs) are cantilevered multilayer grapheme sheets that are seeded from core graphite fibers. The resulting structure offers a possibility of minimizing interfacial losses in transport application, improved interactions with surrounding matrix materials in composites, and a route toward substrate independence for device applications. The mass production of CNPs on the substrate required a method that can provide synchronous feedback on the sample status without pulling them out of the production line. Different optical properties can be observed when surfaces with different roughness are illuminated with a highly coherent light such as a laser beam. Similarly, CNPs …
Simulation, Control And Testing Of Advanced Hydraulic Hybrid Transmissions, Italo M. Ramos, Monika Ivantysynova, Michael Sprengel
Simulation, Control And Testing Of Advanced Hydraulic Hybrid Transmissions, Italo M. Ramos, Monika Ivantysynova, Michael Sprengel
The Summer Undergraduate Research Fellowship (SURF) Symposium
Hydraulic hybrids transmissions have the potentially to substantially improve the fuel efficiency of on road vehicles. In fact recent studies have demonstrated that this technology can improve fuel economy by upwards of 30% over competing electric hybrids. To further improve the fuel economy and performance of this technology a novel blended hydraulic hybrid transmission has been constructed at the Maha Fluid Power Research Center. While this novel hybrid architecture created by the Maha lab has many benefits over conventional systems, there are a number of control challenges present due to several discrete modes of operation. And though improving fuel economy …
The Effects Of Ivc Modulation On Modern Diesel Engines Equipped With Variable Valve Actuation At High Load And Speed, Troy E. Odstrcil, Gregory M. Shaver, Cody M. Allen
The Effects Of Ivc Modulation On Modern Diesel Engines Equipped With Variable Valve Actuation At High Load And Speed, Troy E. Odstrcil, Gregory M. Shaver, Cody M. Allen
The Summer Undergraduate Research Fellowship (SURF) Symposium
Modern diesel compression engines are known for their increased durability, fuel economy and torque when compared with their spark ignition gasoline counterparts. These are some of the reasons why diesel engines are preferred in heavy duty applications such as trains and semi-trucks. During the Heavy Duty Federal Test Procedure transient drive cycle, or HDFTP, nearly 85% of the total fuel burned is at speeds greater than 2000 revolutions per minute (RPM) for the studied engine. Therefore, it is desirable to increase the fuel economy at these loads and speeds. It is hypothesized that the use of late intake valve close …
Development Of A Shape Memory Polymer Soft Microgripper, Marshall Tatro, David J. Cappelleri, Wuming Jing
Development Of A Shape Memory Polymer Soft Microgripper, Marshall Tatro, David J. Cappelleri, Wuming Jing
The Summer Undergraduate Research Fellowship (SURF) Symposium
The ability to control microrobots by means of magnetic fields has become of increasing interest to researchers. These robots’ ability to reach places tethered microrobots otherwise could not leads to many possible applications in the body, such as delivering drugs to targeted locations and performing biopsies. This study shows the use of shape memory polymer (SMP) to wirelessly actuate a microgripper to be used by a controllable microrobot to achieve these functions. Many smart materials were analyzed in order to find the material that most effectively would accomplish wirelessly gripping, manipulating, and releasing a microobject. Multiple microgripper designs were designed, …
Thermal Design Of Three-Dimensional Electronic Assemblies, Yifan Weng, Chun-Pei Chen, Ganesh Subbarayan
Thermal Design Of Three-Dimensional Electronic Assemblies, Yifan Weng, Chun-Pei Chen, Ganesh Subbarayan
The Summer Undergraduate Research Fellowship (SURF) Symposium
Currently, three-dimensional electronic assemblies (3D Packages) are a key technology for enabling heterogeneous integration and “more than Moore” functionality. A critical bottleneck to the viability of 3D Packages is their thermal design. Traditionally, heat spreaders are used as a passive method to reduce the peak temperature as well as temperature gradient on the chip. However, heat spreaders by themselves are often insufficient in stacked, multiple-die containing 3D Packages. Towards this end, to more efficiently remove heat, silicon interposers with through silicon vias (TSV) are used. However, careful design of number and location of TSVs is necessary. In addition, the heat …
Dislocation Avalanche Polycrystalline Nickel, Zhiyang Lin, Cao Lei Dr, Marisol Koslowski Prof.
Dislocation Avalanche Polycrystalline Nickel, Zhiyang Lin, Cao Lei Dr, Marisol Koslowski Prof.
The Summer Undergraduate Research Fellowship (SURF) Symposium
Self-organized criticality (SOC) is widely observed in systems ranging from creep deformation of single crystal ice to the movement of glacier. -The behavior of these SOC systems follows a power law distribution, which is time- and space-scale invariant. Previous phase field simulation of single crystal nickel has shown that plastic flow is characterized by intermittent dislocation avalanches, which can be characterized by a power law distribution. Does this scale invariance also exist in polycrystalline material, in which dislocation avalanches may be hindered by grain boundaries? In this study, we characterize the dislocation loops using homogenous region division algorithm and investigate …
Experimental Characterization And Modelling Of Energy Efficient Fluid Supply Systems, Karina M. Bjorklund, Andrea Vacca, Timothy J Opperwall
Experimental Characterization And Modelling Of Energy Efficient Fluid Supply Systems, Karina M. Bjorklund, Andrea Vacca, Timothy J Opperwall
The Summer Undergraduate Research Fellowship (SURF) Symposium
In applications such as in agriculture, construction, and aerospace applications, high pressure hydraulics is the preferred technology to transmit mechanical power. As a consequence, the energy efficiency of the hydraulic system used to perform the mechanical actuations is of primary concern to reduce the energy consumptions in the abovementioned applications. In an hydraulic system, the primary component determining the energy efficiency is the hydraulic pump. This work focuses on the study of a particular pump design, also referred as external gear pump, particularly used in applications in which the cost of the hydraulic system has to be minimized. The large …
Application Of Ultrasound In The Measurement Of Lubricant Fluid Film Thickness In The Piston-Cylinder Interface Of An Axial Piston Pump, Dhruv Subramaniam, Dan Mizell, Monika Ivantysynova
Application Of Ultrasound In The Measurement Of Lubricant Fluid Film Thickness In The Piston-Cylinder Interface Of An Axial Piston Pump, Dhruv Subramaniam, Dan Mizell, Monika Ivantysynova
The Summer Undergraduate Research Fellowship (SURF) Symposium
In this paper a feasibility study has been conducted to determine a technique for the measurement of lubricant fluid film thickness in the piston-cylinder interface of an axial piston pump. The thickness of the lubricant film has a significant impact on the efficiency of the piston pump yet it still remains an uncertainty. If the lubricant film is too thin then friction will cause excessive damage resulting in deformation of interacting surfaces resulting in further uncertainty in thickness measurement. If the lubricant film is too thick then there is excessive leakage which will compromise the efficiency of the system. Acoustic, …
Numerical Solver For Multiphase Flows, Victor C B Sousa, Carlo Scalo
Numerical Solver For Multiphase Flows, Victor C B Sousa, Carlo Scalo
The Summer Undergraduate Research Fellowship (SURF) Symposium
The technological development of micro-scale electronic devices is bounded by the challenge of dissipating their heat output. Latent heat absorbed by a fluid during phase transition offers exceptional cooling capabilities while allowing for the design of compact heat exchangers. The understanding of heat transport dynamics in the context of multiphase flow physics is hampered by the limited access to detailed flow features offered by experimental measurements. Computational Fluid Dynamics (CFD) can overcome such difficulties by providing a complete description of the three-dimensional instantaneous flow field. Unfortunately, the majority of the numerical investigations in this field at Purdue are carried out …
Test Rig Design For Compact Variable Displacement Vane Pump, Pratik Chawla, Ryan Jenkins, Monika Ivantysynova
Test Rig Design For Compact Variable Displacement Vane Pump, Pratik Chawla, Ryan Jenkins, Monika Ivantysynova
The Summer Undergraduate Research Fellowship (SURF) Symposium
Variable displacement vane pumps (VDVP) are one type of positive displacement pumps used in automatic transmission vehicles for lubricating the gears, cooling the transmission and actuating the clutches. Though fixed displacement pumps are widely used, they output a constant effective flow at a given speed. Depending on pump sizing considerations, the pump can be oversized at high speeds because flow demand of the transmission is independent of engine speed. The excess flow returns to the tank through an orifice that causes the oil to heat up, increasing the energy required for cooling and reducing the efficiency of the transmission. A …
Measured And Predicted Performance Of A Photovoltaic Grid-Connected System In A Humid Subtropical Climate, Racquel Lovelace
Measured And Predicted Performance Of A Photovoltaic Grid-Connected System In A Humid Subtropical Climate, Racquel Lovelace
Mechanical Engineering Theses
Solar energy is an alternative energy source that has the potential to provide energy for the very increasing global population. Photovoltaic modules are the means by which solar energy is collected. Photovoltaic modules convert sunlight into direct-current (DC) electricity which can then be converted to alternating current (AC) electricity and used in regular household systems. This research aimed to determine the measured and predicted performance of a photovoltaic grid-connected system in a humid subtropical climate. Simulation and numerical models were used to determine the predicted performance of the system to be compared to the recorded data from the system. In …
A Community Of World Class Engineering Students, Devshikha Bose, Krishna Pakala
A Community Of World Class Engineering Students, Devshikha Bose, Krishna Pakala
Mechanical and Biomedical Engineering Faculty Publications and Presentations
This paper is a work in progress report on an Engineering Living Learning Community (LLC) at Boise State University. Though the LLC under consideration is for the time period of Fall 2014 to Fall 2016, this report is limited to student as well as instructor anecdotal and self-reported experiences, observations, and evaluations made during Fall 2014 and Spring 2015. The mission of the Residential College program at BSU is to integrate student academic and personal life in a residential setting, so as to develop interdisciplinary knowledge, foster deep learning, and maximize student success. In support of this goal, students completed …
Entropy Minimization Design Approach Of Supersonic Internal Passages, Jorge Sousa, Guillermo Paniagua
Entropy Minimization Design Approach Of Supersonic Internal Passages, Jorge Sousa, Guillermo Paniagua
School of Aeronautics and Astronautics Faculty Publications
Fluid machinery operating in the supersonic regime unveil avenues towards more compact technology. However, internal supersonic flows are associated with high aerodynamic and thermal penalties, which usually prevent their practical implementation. Indeed, both shock losses and the limited operational range represent particular challenges to aerodynamic designers that should be taken into account at the initial phase of the design process. This paper presents a design methodology for supersonic passages based on direct evaluations of the velocity field using the method of characteristics and computation of entropy generation across shock waves. This meshless function evaluation tool is then coupled to an …
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 …
Design And Fabrication Of Liquid Scintillator Counter, Andrea Calderon Saucedo, John L. Orrell
Design And Fabrication Of Liquid Scintillator Counter, Andrea Calderon Saucedo, John L. Orrell
STAR Program Research Presentations
Pacific Northwest National Laboratory (PNNL) is currently developing an ultra-low background liquid scintillator counter (ULB LSC) in the shallow underground laboratory. At a depth of 35-meters water-equivalent, the underground laboratory has a multi-layered shielding to keep out cosmic-ray induced background. The ULB LSC, which is located in a clean room facility, is a multi-layered design made up of various materials, including plastic scintillator veto panels, borated polyethylene, lead and copper. These layers help lower the contributions of the terrestrial background and intrinsic background, resulting from the impurities present in the materials, to the overall background count rate observed by the …