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Articles 1 - 30 of 1902

Full-Text Articles in Mechanical Engineering

Effect Of Catholyte Concentration On Current Production During Chocolate Industry Wastewater Treatment By A Microbial Fuel Cell, Diana Rahayuning Wulan, Suprihanto Notodarmojo Nov 2020

Effect Of Catholyte Concentration On Current Production During Chocolate Industry Wastewater Treatment By A Microbial Fuel Cell, Diana Rahayuning Wulan, Suprihanto Notodarmojo

Makara Journal of Technology

Microbial fuel cells (MFCs) use bacteria as a catalyst to oxidize organic and/or inorganic substrates and produce electric currents. Wastewater could function as an electron donor in the anode chamber and, thus, represents a very promising energy source. Catholytes, as electron acceptors, influence power production in MFCs by increasing the availability of electrons. The present research aims to determine the influence of catholyte concentration on current production in an aerobic two-chamber MFC. Aerobic treatment was carried out in the two-chamber MFC operated in an incubator at 37  1 °C with and without aeration in the cathode chamber. Wastewater from ...


Evaluation Of Il-17a And Il-17f Gene Expression In Peripheral Blood Mononuclear Cells In Different Clinical Stages Of Chronic Hepatitis B Infection In An Iranian Population, Tannaz Akbari Kolagar, Seyed Reza Mohebbi, Fatemeh Ashrafi, Shahrzad Shoraka, Hamid Asadzadeh Aghdaei, Mohammad Reza Zali Nov 2020

Evaluation Of Il-17a And Il-17f Gene Expression In Peripheral Blood Mononuclear Cells In Different Clinical Stages Of Chronic Hepatitis B Infection In An Iranian Population, Tannaz Akbari Kolagar, Seyed Reza Mohebbi, Fatemeh Ashrafi, Shahrzad Shoraka, Hamid Asadzadeh Aghdaei, Mohammad Reza Zali

Makara Journal of Technology

Hepatitis B virus (HBV) infection is one of the main causes of liver damage, which can also lead to chronic hepatitis B (CHB) infection. More than 240 million individuals worldwide are chronic carriers of HBV. Among individuals with CHB who are untreated, approximately 15% – 40% will progress to liver cirrhosis or cancer. The interactions between HBV and host immune response play significant roles in the progression of CHB. CHB can be generally divided into four different clinical phases: immune tolerance (IT), immune clearance, inactive carrier, and Hepatitis B surface antigen (HBsAg)-negative reactivation phase (ENEG). Many studies showed that interleukins ...


Redesign Of Product Packaging With Kansei Engineering: Empirical Study On Small-Medium Enterprises In Indonesia, Amalia Suzianti, A. Aldianto Nov 2020

Redesign Of Product Packaging With Kansei Engineering: Empirical Study On Small-Medium Enterprises In Indonesia, Amalia Suzianti, A. Aldianto

Makara Journal of Technology

Small-medium enterprises (SMEs) in Indonesia have been proven to be one of the important pillars of the national economy. Unfortunately, some problems hinder their development, and one of the critical problems is the quality of product packaging. The packages of SME products are considered poor, dirty, and unattractive. Packaging problem is one of the factors why consumers are less interested in buying and why SME products always lose in the competition with other products. This study discusses how to employ Kansei engineering to design better SME product packaging with a focus on psychological (affective) aspects. This research concludes that there ...


Effect Of Landfill Leachates On Some Water Quality Indicators Of Selected Surface Water And Groundwater At Ilokun, Ado-Ekiti, Nigeria, Olorunwa Omofunmi, Adesola Satimehin, Abraham Oloye, Okwunna Umego Nov 2020

Effect Of Landfill Leachates On Some Water Quality Indicators Of Selected Surface Water And Groundwater At Ilokun, Ado-Ekiti, Nigeria, Olorunwa Omofunmi, Adesola Satimehin, Abraham Oloye, Okwunna Umego

Makara Journal of Technology

This study was conducted to examine the impact of dumpsites on the quality of groundwater and surface water. The water samples and leachates were collected from dumpsites in respective zones. The physicochemical properties of the samples were examined and determined in accordance with the standards of the American Public Health Association. Results indicated that the groundwater and surface water that are close to the dumpsites have an electrical conductivity of 385 and 245 Sd/cm, total dissolved solids of 168 and 128 mg/L, a turbidity of 4.6 and 22 NTU, a total alkalinity of 103 and 50 mg ...


Microstrip Filters: A Review Of Different Filter Designs Used In Ultrawide Band Technology, Hussain Bohra, Giriraj Prajapati Nov 2020

Microstrip Filters: A Review Of Different Filter Designs Used In Ultrawide Band Technology, Hussain Bohra, Giriraj Prajapati

Makara Journal of Technology

In this study, optimization techniques applied in designing microstrip bandpass ultra-wideband (UWB) filters are presented. Optimization based on various defected ground structure techniques, resonator designs, and type of dielectric materials is discussed. Microstrip bandpass filters implemented at UWB frequency bands used in wireless communication systems have key features to control frequency response in passband and stopband. Optimization techniques are studied to attain optimum performance of bandpass microstrip filters to ensure minimum insertion loss, high selectivity, compactness, sharp transitions at cut-off frequencies, high return loss, and excellent linearity. Extensive study shows that proper selection of fabrication techniques and type of material ...


Effect Of Pvdf-Ca Ratio On Electrospun Membrane For Water–Oil Filtration Application, Mohamad Haziq Alias, Izan Izwan Misnon, Rajan Jose Nov 2020

Effect Of Pvdf-Ca Ratio On Electrospun Membrane For Water–Oil Filtration Application, Mohamad Haziq Alias, Izan Izwan Misnon, Rajan Jose

Makara Journal of Technology

Oil spillage and generation of industrial water–oil wastewater mixture ignite a focus on filtration technology. Electrospinning technique provides a versatile route in producing tunable diameter and pores in nanofiber filtration membrane development. In this work, polyvinylidene difluoride (PVDF) and cellulose acetate (CA) electrospun membrane at different concentration ratios were synthesized for water–oil filtration application. The polymeric solutions were characterized using viscometer and conductivity testing, whereas the membranes were analyzed using contact angle, tensile test, scanning electron microscopy (SEM), and filtration testing of oil (dichloromethane). Conductivity test showed a decreased conductivity along with decrement of CA ratio in the ...


Performance-Shaping Factors Of Personnel Performing Evacuation And Escape On Offshore Installations In Tropical, Norafneeza Norazahar, Nur Azizah Arryanie Morshidi, Arshad Ahmad, Wijayanuddin Mohd Ali Nov 2020

Performance-Shaping Factors Of Personnel Performing Evacuation And Escape On Offshore Installations In Tropical, Norafneeza Norazahar, Nur Azizah Arryanie Morshidi, Arshad Ahmad, Wijayanuddin Mohd Ali

Makara Journal of Technology

Performance-shaping factors (PSFs) are used to address the strengths and weaknesses of workers performing escape and evacuation activities. These PSFs are time, environmental factors as stressors, complexity of activities, experiences and training, interaction between workers and emergency equipment, workers’ physical conditions, and procedures. This paper presents a survey work on fitness for the duty of workers performing basic offshore survival and emergency response training. The training provides credible scenarios of escape and evacuation in case of an emergency of offshore installations in tropical waters. The survey is conducted among participants of the tropical basic offshore safety induction & emergency training with ...


Formula Sae Monocoque Chassis Development, Kc Egger, Brian Ford, Kyle Nagao, Neal Sharma, Donovan Zusalim Aug 2020

Formula Sae Monocoque Chassis Development, Kc Egger, Brian Ford, Kyle Nagao, Neal Sharma, Donovan Zusalim

Mechanical Engineering

Formula SAE is a collegiate competition hosted by SAE International with the primary goal being to design, manufacture, and race an open wheel race car. The Cal Poly Racing Formula SAE team strives for improvement every race season and has remained competitive as a result. The 2019-2020 management team determined that further research and development towards the chassis would yield the greatest performance benefit for future seasons, as the previous chassis platform limited packaging and mounting options for vehicle subsystems which interfaced with the chassis.

A redesign of the Cal Poly Racing Formula SAE team’s carbon fiber reinforced polymer ...


Wavelength Decomposition Of Hybrid Additive Manufacturing Power Signals And Their Relationship With Surface Integrity, Xingtao Wang Jul 2020

Wavelength Decomposition Of Hybrid Additive Manufacturing Power Signals And Their Relationship With Surface Integrity, Xingtao Wang

Mechanical (and Materials) Engineering -- Dissertations, Theses, and Student Research

Additive Manufacturing (AM) has been a promising manufacturing technology in industrial applications and gained a massive amount of attention from researchers all over the world. Directed Energy Deposition (DED) is an AM process in which focused thermal energy is used to fuse materials by melting as they are deposited. One of the most significant challenges involved in current metal AM processes is improving repeatability and consistency. Substantial effort has already been invested in this area of research.

In this dissertation, a milling tool not only played a role in subtractive manufacturing but also acted as a method of monitoring the ...


Simultaneous Effects Of Rice Husk Silica And Silicon Carbide Whiskers On The Mechanical Properties And Morphology Of Sodium Geopolymer, Akm Rahman, Nihkil Gupta Jun 2020

Simultaneous Effects Of Rice Husk Silica And Silicon Carbide Whiskers On The Mechanical Properties And Morphology Of Sodium Geopolymer, Akm Rahman, Nihkil Gupta

Publications and Research

The current research is focused on developing a geopolymer binder using rice husk ash–derived silica nanoparticles. Four types of rice husks were collected directly from various rice fields of Bangladesh in order to evaluate the pozzolanic activity and compatibility of the derived rice husk ashes with precursors of sodium-based geopolymers. Silicon carbide whiskers were introduced into sodium-based geopolymers in order to evaluate the response of silicon carbide whiskers to the interfacial bonding and strength of sodium-based geopolymers along with rice husk ashes. Compression, flexural and short beam shear tests were performed to investigate the synergistic effect of rice husk ...


Conversion Of Self-Contained Breathing Apparatus Mask To Open Source Powered Air-Purifying Particulate Respirator For Fire Fighter Covid-19 Response, Benjamin R. Hubbard, Joshua M. Pearce Jun 2020

Conversion Of Self-Contained Breathing Apparatus Mask To Open Source Powered Air-Purifying Particulate Respirator For Fire Fighter Covid-19 Response, Benjamin R. Hubbard, Joshua M. Pearce

Michigan Tech Publications

To assist firefighters and other first responders to use their existing equipment for respiration during the COVID-19 pandemic without using single-use, low-supply, masks, this study outlines an open source kit to convert a 3M-manufactured Scott Safety self-contained breathing apparatus (SCBA) into a powered air-purifying particulate respirator (PAPR). The open source PAPR can be fabricated with a low-cost 3-D printer and widely available components for less than $150, replacing commercial conversion kits saving 85% or full-fledged proprietary PAPRs saving over 90%. The parametric designs allow for adaptation to other core components and can be custom fit specifically to fire-fighter equipment, including ...


Miniaturized Ultraviolet Imager Phase Iii, Bradley D. Albright, Nicolas A. Armenta, Colin W. Harrop Jun 2020

Miniaturized Ultraviolet Imager Phase Iii, Bradley D. Albright, Nicolas A. Armenta, Colin W. Harrop

Mechanical Engineering

This document details the work to date, June 9, 2020, done by the Cal Poly Mechanical Engineering senior project team, Miniaturized Ultraviolet Imager: Phase III (MUVI III), sponsored by the University of California, Berkeley – Space Sciences Laboratory (UCB SSL). MUVI III is the third senior project team of an ongoing design, MUVI: the prototype of a 2U sized CubeSat intended to capture aurora images in the ionosphere. The first team, MUVI I, finished development of the UV imager. The second team, MUVI II, designed the mirror mounting and deployable door mechanisms. The goal of MUVI phase III is to design ...


Analysis Of Burning Wood In The Transient State And The Application To Structural Design, Roberta Veliz, Kimberly Guzman Jun 2020

Analysis Of Burning Wood In The Transient State And The Application To Structural Design, Roberta Veliz, Kimberly Guzman

Architectural Engineering

Determining the extent of the contribution of exposed timber on compartment fire dynamics in open floor plans is a complex process. Designers traditionally used compartmentalization design methods which create spaces where flashover is likely, given the fuel load and ventilation conditions. However, due to the large geometric dimensions and spread of fuel, fires in open floor plans are more likely to remain as localized or traveling fires. As such, an understanding of not only ignition potential but also flame spread is critical to characterizing the contribution of exposed timber. An integral step in characterizing the potential contribution is through an ...


Design For Additive Manufacturing, Michael Charonnat, Leonardo Franco-Muñoz, Sam Noble, J.P. Purdom Jun 2020

Design For Additive Manufacturing, Michael Charonnat, Leonardo Franco-Muñoz, Sam Noble, J.P. Purdom

Mechanical Engineering

This document outlines the critical design details and timeline for the Design for Additive Manufacturing Senior Project sponsored by Solar Turbines, Inc. The scope of this project encompasses the redesign of two of Solar Turbine’s cast parts for metal additive manufacturing in order to minimize lead time, cost, and weight. With the overall objective of performing in-depth analysis exploring affordability & feasibility, this redesign process will aid Solar Turbines in expanding their knowledge of Design for Additive Manufacturing principles and enable them to further incorporate the use of additive manufacturing into their production processes. The first part that the team ...


Open Source High-Temperature Reprap For 3-D Printing Heat-Sterilizable Ppe And Other Applications, Noah G. Skrzypczak, Nagendra Gautam Tanikella, Joshua M. Pearce May 2020

Open Source High-Temperature Reprap For 3-D Printing Heat-Sterilizable Ppe And Other Applications, Noah G. Skrzypczak, Nagendra Gautam Tanikella, Joshua M. Pearce

Michigan Tech Publications

Thermal sterilization is generally avoided for 3-D printed components because of the relatively low deformation temperatures for common thermoplastics used for material extrusion-based additive manufacturing. 3-D printing materials required for high-temperature heat sterilizable components for COVID-19 and other applications demands 3-D printers with heated beds, hot ends that can reach higher temperatures than polytetrafluoroethylene (PTFE) hot ends and heated chambers to avoid part warping and delamination. There are several high temperature printers on the market, but their high costs make them inaccessible for full home-based distributed manufacturing required during pandemic lockdowns. To allow for all these requirements to be met ...


Fly Ash Based Geopolymer For High Temperature And High Compressive Strength Applications In Aggressive Environment, Aaryan Manoj Nair, Akm S. Rahman May 2020

Fly Ash Based Geopolymer For High Temperature And High Compressive Strength Applications In Aggressive Environment, Aaryan Manoj Nair, Akm S. Rahman

Publications and Research

Geopolymers are the results of geosynthetic reactions between aluminosilicates and strong bases. This results in chemical bonds between aluminum (Al), Silicon (Si)and oxygen (O) composing polymer rings in tetrahedral coordination. These bonds give them widespread useful applications such as high heat bearing ceramics, and base construction material whilst being far more environmentally conscious. The purpose of the experiment is to examine the effect of Silicon Carbide whisker and inorganic glass particles on thermal and mechanical properties of Geopolymers. This study will help understand the effect of various compositions and concentrations of SiO2 in mechanical strength. In this experiment ...


Parametric Nasopharyngeal Swab For Sampling Covid-19 And Other Respiratory Viruses: Open Source Design, Sla 3-D Printing And Uv Curing System, Nicole Gallup, Adam Pringle, Shane Oberloier, Nagendra Gautam Tanikella, Joshua M. Pearce May 2020

Parametric Nasopharyngeal Swab For Sampling Covid-19 And Other Respiratory Viruses: Open Source Design, Sla 3-D Printing And Uv Curing System, Nicole Gallup, Adam Pringle, Shane Oberloier, Nagendra Gautam Tanikella, Joshua M. Pearce

Michigan Tech Publications

Access to nasopharyngeal swabs for sampling remain a bottleneck in some regions for COVID19 testing. This study develops a distributed manufacturing solution using only an open source manufacturing tool chain consisting of two types of open source 3-D printing and batch UV curing, and provides a parametric fully free design of a nasopharyngeal swab. The swab was designed using parametric OpenSCAD in two components (a head with engineered break point and various handles), which has several advantages: i) minimizing print time on relatively slow SLA printers, ii) enabling the use of smaller print volume open source SLA printers, iii) reducing ...


Effects Of Hard-To-Soft Segment Ratios On The Synthesis And Physico-Mechanical Properties Of Polyurethane Films, Aaron C. Wilson May 2020

Effects Of Hard-To-Soft Segment Ratios On The Synthesis And Physico-Mechanical Properties Of Polyurethane Films, Aaron C. Wilson

Mechanical Engineering Theses

Blood-contacting cardiovascular stents often induce a secondary clotting event due to unrestricted enzymatic activities. The use of hemocompatible polyurethane coatings on these implantable devices is one of the most promising methods to reduce device rejection. In this study, four commercial polyurethane films of various thicknesses and compositions were evaluated for their anticoagulation properties. Results suggested that these films exhibited excellent thermal and physico-mechanical properties while capable of increasing contact time with blood plasma by over a thousand-fold as compared to a control surface. Due to the unknown structure and composition of these commercial films, polyurethane samples were synthesized from toluene ...


Comparative Analysis And Dynamic Response Of Garolites Under Temperature Spectrum Using Low Velocity Impact Test, Birendra Chaudhary May 2020

Comparative Analysis And Dynamic Response Of Garolites Under Temperature Spectrum Using Low Velocity Impact Test, Birendra Chaudhary

Honors Theses

The purpose of this study was to examine the dynamic response of three different grades of garolites under the temperature spectrum. High-Temperature G-11 Sheet (HTG), Impact Resistance Garolite E-glass (HIG), and Economical Garolite (EG) were tested using an Instron Dynatup 8250 impact tester. Three specimens were used for all three composites and were tested at 6 different temperatures, -10oC, 25oC, 50oC, 100oC, 150oC and 200oC using the Low-Velocity Impact Machine with 20 Kip punch shear load cell. The results showed that HIG had the highest resistance to punch ...


Dynamic Characterization Of Duroprotect, A Fiber-Reinforced Ballistics Composite, Ivy A. Turner May 2020

Dynamic Characterization Of Duroprotect, A Fiber-Reinforced Ballistics Composite, Ivy A. Turner

Honors Theses

Dynamic characterization of materials has become increasingly common, as it is important to understand how materials behave under sudden loads. Understanding these properties can aid in material selection for novel designs. DuroProtect, a fiber-reinforced ballistics composite developed by Rӧchling, was tested for its dynamic properties at high strain-rates. The Split Hopkinson Pressure Bar (SHPB) test was used to obtain dynamic properties at high strain-rates under compressive loading conditions. Tests were initially conducted to validate force equilibriums for each sample. The data measured from the strain gages mounted on the incident and transmission bars and the elastic wave propagation theories yields ...


In-Service Performance Evaluation Of Concrete Sloped End Treatments In Iowa, Jessica Lingenfelter May 2020

In-Service Performance Evaluation Of Concrete Sloped End Treatments In Iowa, Jessica Lingenfelter

Mechanical (and Materials) Engineering -- Dissertations, Theses, and Student Research

Sloped end treatments were historically developed as low-cost, low-maintenance end treatments for rigid features like concrete barriers and bridge rails. Crash testing indicated that sloped end treatments are associated with significant instability for impacting vehicles. However, the in-service performance of these features has not been evaluated. An in-service performance evaluation (ISPE) was performed to evaluate vehicle crashes with sloped end treatments in Iowa between 2008 and 2017. Researchers generated a geographic inventory of sloped end treatment locations, reviewed crash narratives and scene diagrams for crashes near these sloped end treatments, and calculated an estimated crash rate and crash cost for ...


Additive Manufacturing And How 3d Printing Is Fighting Covid-19, Raghavan Srinivasan, Ahsan Mian, Joy Gockel, Laura M. Luehrmann May 2020

Additive Manufacturing And How 3d Printing Is Fighting Covid-19, Raghavan Srinivasan, Ahsan Mian, Joy Gockel, Laura M. Luehrmann

Mechanical and Materials Engineering Faculty Publications

This is the fourth installment in the Shelter in Place (SiP) Lecture series. This installment covers the creative ways that 3D printing has supported efforts to combat the pandemic. It covers the basics of what 3D printing is, some of the various creative projects that have used 3D printing to combat the pandemic, among other topics and questions by the pandemic.


Impact Resistance Of Fiber-Reinforced Composites Using Computational Simulations, Maitham Alabbad May 2020

Impact Resistance Of Fiber-Reinforced Composites Using Computational Simulations, Maitham Alabbad

Electronic Theses and Dissertations

Composite materials are widely used in aerospace, automotive and wind power industries due to their high strength-to-weight and stiffness-to-weight ratios and their improved mechanical properties compared to metals. The damage resistance of composite materials due to low velocity impact depends on fiber breakage, matrix cracking and delamination between the interfaces. In this research, a numerical investigation of low velocity impact response of a multidirectional symmetric carbon-epoxy composite laminate is carried out and presented. Two different finite element models are developed for composite laminates made of non-crimp fabric to investigate their behavior under different levels of impact energy. In the first ...


Development Of A Novel Vehicle Guidance System: Vehicle Risk Mitigation And Control, Michael Sweigard Apr 2020

Development Of A Novel Vehicle Guidance System: Vehicle Risk Mitigation And Control, Michael Sweigard

Mechanical (and Materials) Engineering -- Dissertations, Theses, and Student Research

Over a half of fatal vehicular crashes occur due to vehicles leaving their designated travel lane and entering other lanes or leaving the roadway. Lane departure accidents also result in billions of dollars in cost to society. Recent vehicle technology research into driver assistance and vehicle autonomy has developed to assume various driving tasks. However, these systems are do not work for all roads and travel conditions. The purpose of this research study was to begin the development a novel vehicle guidance approach, specifically studying how the vehicle interacts with the system to detect departures and control the vehicle

A ...


Evaluation And Update Of Mash Test Vehicles, Kellon B. Ronspies Apr 2020

Evaluation And Update Of Mash Test Vehicles, Kellon B. Ronspies

Mechanical (and Materials) Engineering -- Dissertations, Theses, and Student Research

The Manual for Assessing Safety Hardware (MASH) requires full-scale crash testing of roadside features using worst practical impact conditions. Vehicle selection for full-scale crash testing is intended to be representative of the contemporary passenger vehicle fleet. Researchers at the Midwest Roadside Safety Facility (MwRSF) investigated attributes of passenger vehicle sales to determine if the vehicle selection criteria shown in MASH should be revised to accommodate changes in the vehicle fleet. A methodology was considered to affordably re-analyze the vehicle fleet when necessary to ensure MASH vehicle selection criteria are reflective of vehicles currently on roadways.

Representative vehicles were documented using ...


Crystallographic Facet Selective Her Catalysis: Exemplified In Fep And Nip2 Single Crystals, Bryan Owens-Baird, Juliana P.S. Sousa, Yasmine Ziouani, Dmitri Y. Petrovykh, Nikolai A. Zarkevich, Duane D. Johnson, Yury V. Kolen'ko, Kirill Kovnir Apr 2020

Crystallographic Facet Selective Her Catalysis: Exemplified In Fep And Nip2 Single Crystals, Bryan Owens-Baird, Juliana P.S. Sousa, Yasmine Ziouani, Dmitri Y. Petrovykh, Nikolai A. Zarkevich, Duane D. Johnson, Yury V. Kolen'ko, Kirill Kovnir

Ames Laboratory Accepted Manuscripts

How the crystal structures of ordered transition-metal phosphide catalysts affect the hydrogen-evolution reaction (HER) is investigated by measuring the anisotropic catalytic activities of selected crystallographic facets on large (mm-sized) single crystals of iron-phosphide (FeP) and monoclinic nickel-diphosphide (m-NiP2). We find that different crystallographic facets exhibit distinct HER activities, in contrast to a commonly held assumption of severe surface restructuring during catalytic activity. Moreover, density-functional-theory-based computational studies show that the observed facet activity correlates well with the H-binding energy to P atoms on specific surface terminations. Direction dependent catalytic properties of two different phosphides with different transition metals, crystal structures, and ...


Thermal Modeling Of Additive Manufacturing Using Graph Theory: Validation With Directed Energy Deposition, Jordan Severson Apr 2020

Thermal Modeling Of Additive Manufacturing Using Graph Theory: Validation With Directed Energy Deposition, Jordan Severson

Mechanical (and Materials) Engineering -- Dissertations, Theses, and Student Research

Metal additive manufacturing (AM/3D printing) offers unparalleled advantages over conventional manufacturing, including greater design freedom and a lower lead time. However, the use of AM parts in safety-critical industries, such as aerospace and biomedical, is limited by the tendency of the process to create flaws that can lead to sudden failure during use. The root cause of flaw formation in metal AM parts, such as porosity and deformation, is linked to the temperature inside the part during the process, called the thermal history. The thermal history is a function of the process parameters and part design.

Consequently, the first ...


Angle-Iron Feed Measuring Device, Jason Robertson, Alex Welling, Jacob Burns Apr 2020

Angle-Iron Feed Measuring Device, Jason Robertson, Alex Welling, Jacob Burns

Scholar Week 2016 - present

Steel and iron are the building blocks with which we construct our world. From buildings to machines to transportation the use of these materials can be found in all aspects of life. In their crude form they do not have much use, so manufacturers standardize various shapes and sizes to create usable resources. These include bars, rods, beams, sheet, and angle iron. The team made up of three engineering students Jake Burns, Jason Robertson, and Alex Welling is working with a company called Peddinghaus. Peddinghaus produces equipment and machines to process steel and iron in their standard forms, such as ...


Laser Micropatterning Effects On Corrosion Resistance Of Pure Magnesium Surfaces, Yahya Efe Yayoglu Apr 2020

Laser Micropatterning Effects On Corrosion Resistance Of Pure Magnesium Surfaces, Yahya Efe Yayoglu

Graduate Theses and Dissertations

Magnesium and its alloys are good candidates to manufacture medical implants. They have excellent biocompatibility and because they biodegrade secondary surgical operation to remove the implant could be eliminated. However, in aqueous environments, magnesium alloys rapidly corrode, resulting in premature degradation of the implant along with biologically intolerable hydrogen gas generation. In literature, there are multiple studies focused on creating water repelling hydrophobic magnesium surfaces in order to decrease corrosion rates. Hydrophobic properties can be achieved by creation of a roughness profile on an initially smooth surface combined with a treatment that reduces the free surface energy. In theory, hydrophobic ...


Single-Atom-Layer Traps In A Solid Electrolyte For Lithium Batteries, Feng Zhu, Md Shafiqul Islam, Lin Zhou, Zhenqi Gu, Ting Liu, Xinchao Wang, Jun Luo, Ce-Wen Nan, Yifei Mo, Cheng Ma Apr 2020

Single-Atom-Layer Traps In A Solid Electrolyte For Lithium Batteries, Feng Zhu, Md Shafiqul Islam, Lin Zhou, Zhenqi Gu, Ting Liu, Xinchao Wang, Jun Luo, Ce-Wen Nan, Yifei Mo, Cheng Ma

Ames Laboratory Accepted Manuscripts

In order to fully understand the lithium-ion transport mechanism in solid electrolytes for batteries, not only the periodic lattice but also the non-periodic features that disrupt the ideal periodicity must be comprehensively studied. At present only a limited number of non-periodic features such as point defects and grain boundaries are considered in mechanistic studies. Here, we discover an additional type of non-periodic feature that significantly influences ionic transport; this feature is termed a “single-atom-layer trap” (SALT). In a prototype solid electrolyte Li0.33La0.56TiO3, the single-atom-layer defects that form closed loops, i.e., SALTs, are found ubiquitous by atomic-resolution electron ...