Engineering Commons^™

Cobalt Chromium In Biomedical Applications And The Development Of A Pspp Map, Nouralhouda Jamal

Bagley College of Engineering Publications and Scholarship

During the world wars, Cobalt-Chromium (Co-Cr) alloys gained prominence for their use in aircraft engine components, where they exhibited high temperature strength and durability. They are used in a wide range of industries due to their unique set of qualities, particularly strength, corrosion resistance, and biocompatibility. They have emerged as versatile materials with a broad spectrum of applications, from aerospace and automotive components to biomedical implants.

This paper presents a thorough analysis of its composition, processing techniques, microstructure, mechanical properties, and performance characteristics. The primary goal of this project is to develop a PSPP (Process, structure, properties, and performance) map …

Cognitive Performance In Midlife Type 2 Diabetes: Results Form The Enbind Study, A. H. Dyer, L. Mckenna, G. Gamage, N. M. Bourke, Isabelle Killane, M. Widdowson, C. P. Woods, J. Gibney, R. Reilly, D. O'Neill, S. P. Kennelly

Articles

Aims: To establish the impact of uncomplicated type 2 diabetes on cognitive and neuropsychological performance in midlife. Methods: We performed a cross-sectional study of middle-aged adults with uncomplicated type 2 diabetes and a cohort of healthy control participants. General cognition was assessed using the Montreal Cognitive Assessment test and neuropsychological assessment was undertaken using a detailed neuropsychological assessment battery. Results: A total of 152 participants (102 with type 2 diabetes and 50 controls) were recruited (mean age 52 ± 8 years, 51% women). Participants with midlife type 2 diabetes were more than twice as likely to make an error on …

Electrical Response Of Thermoelectric Generator To Geometry Variation Under Transient Thermal Boundary Condition, Elias Yazdanshenas, Alireza Rezania, Meysam Karami Rad, Lasse Rosendahl

Mechanical & Aerospace Engineering Faculty Publications

A three-dimensional numerical model is applied in this study to illustrate the electrical response of a thermoelectric generator (TEG) during transient heat flux at the hot side. In this work, various types of thermal boundary conditions are considered to evaluate the performance of the TEG. Thus, a TEG under pulsed heat flux is studied numerically, and the numerical model is verified by experimental results. With the consideration of a defined reference geometry, different heat flux frequencies are applied in order to evaluate the corresponding electrical output by the TEG. In addition, variation of the module performance for various TEG leg …

In-Field Fuel Use And Load States Of Agricultural Field Machinery, Santosh Pitla, Joe D. Luck, Jared Werner, Nannan Lin, Scott A. Shearer

Biological Systems Engineering: Papers and Publications

The ability to define in-field tractor load states offers the potential to better specify and characterize fuel consumption rate for various field operations. For the same field operation, the tractor experiences diverse load demands and corresponding fuel use rates as it maneuvers through straight passes, turns, suspended operation for adjustments, repair and maintenance, and biomass or other material transfer operations. It is challenging to determine the actual fuel rate and load states of agricultural machinery using force prediction models, and hence, some form of in-field data acquisition capability is required. Controller Area Networks (CAN) available on the current model tractors …

Ni-Doped Sr2Fe1.5Mo0.5O6-Δ As Anode Materials For Solid Oxide Fuel Cells, Guoliang Xiao, Siwei Wang, Ye Lin, Zhibin Yang, Minfang Han, Fanglin Chen

Faculty Publications

10% Ni-doped Sr₂Fe_1.5Mo_0.5O_6-δ with A-site deficiency is prepared to induce in situ precipitation of B-site metals under anode conditions in solid oxide fuel cells. XRD, SEM and TEM results show that a significant amount of nano-sized Ni-Fe alloy metal phase has precipitated out from Sr_1.9Fe_1.4Ni_0.1Mo_0.5O_6-δ upon reduction at 800^◦C in H₂. The conductivity of the reduced composite reaches 29 S cm⁻¹ at 800^◦C in H₂. Furthermore, fuel cell performance of the composite anode Sr_{1.9 …}

Numerical Simulation Of Convection In Triangular Cavities To Predict Solar Still Performance, Jeremy D. Lefevre, W. Jerry Bowman, Matthew R. Jones

Faculty Publications

To improve modeling of solar still behavior, the convection correlations currently used need to be improved upon. Variations in operating parameters and cover geometries make it difficult to use a single correlation to describe the operation of all solar stills. In this work, three right triangles (representing covers at 15, 30, and 45 deg) were modeled, meshed, and solved to predict the convection heat transfer inside for a variety of operating conditions. For a correlation of the form Nu = C · Raⁿ, it was found that C = 1.1, 0.60, and 0.71, and n = 0.19, 0.24, …

Performance Of Solid Oxide Iron-Air Battery Operated At 550°C, Xuan Zhao, Yunhui Gong, Xue Li, Nansheng Xu, Kevin Huang

Faculty Publications

“Metal-air” batteries have garnered much attention in recent years due to their high intrinsic specific energy and use of inexhaustible and storage-free oxygen source -air- for the “metal-oxygen” reaction. In this study, we report theperformance of a new type of all solid-state “iron-air” battery operated at 550°C. The results show that CeO₂ nanoparticles incorporated into the Fe-Fe₃O₄ redox-couple can improve the specific energy (Wh/kg) and round trip efficiency by 15% and 29%, respectively, over the baseline Fe-Fe₃O₄ battery. Use of supported Fe-Fe₃O₄ nanoparticles as the redox couple can increase the …

Design Of Experimental Methods To Test The Performance Of Pads And Helmets Under Blast Loading Conditions, Kurtis Palu

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Improvised explosive devices (IEDs) have become a primary weapon in conflicts against US and allied forces. Improvements in body armor and medicine have increased the survivability of such events. These factors have caused an increase in traumatic brain injury (TBI) and mild traumatic brain injury (mTBI) induced by primary blast waves. Injury mechanisms caused from primary blast waves are not clearly understood or defined. How primary blast waves interact with materials or between narrow gaps found between helmet pads is not known. Two novel test fixtures were developed to provide a basic understanding of these two issues.

The first fixture …

Experimental Testing And Finite-Element Modeling To Evaluate The Effects Of Aggregate Angularity On Bituminous Mixture Performance, Leonardo T. Souza, Yong-Rak Kim, Flavio V. Souza, Leandro S. Castro

Department of Engineering Mechanics: Faculty Publications

This study evaluates the effects of aggregate angularity in bituminous mixtures. Previous studies have predominantly focused on the effects of aggregate angularity on the resistance to permanent deformation, while little work has investigated the role of aggregate angularity related to mixture volumetrics and fatigue fracture performance. To investigate the effect of aggregate angularity on mixture performance and characteristics, five mixes with different combinations of coarse and fine aggregate angularity are evaluated by performing the uniaxial static creep test and the indirect tensile fracture energy test. The asphalt pavement analyzer test is also performed with five-year field project mixtures. Fracture energy …

Performance Analysis Of Solar Walls In Minnesota: Final Project Report, Patrick A. Tebbe, Saeed Moaveni, Louis Schwartzkopf

Mechanical and Civil Engineering Department Publications

A study of unglazed transpired solar collectors (referred to as solar walls for this report), has been undertaken. Several installations in the Twin Cities, MN region have been identified, researched, and studied. A combination of weather stations, data logging systems, and building energy management systems were used to collect experimental data on four buildings. Performance calculations were then performed for these buildings and compared with various performance/modeling tools.

An Analysis Of Pressure Gasoline And Pressure Kerosene Stoves, Arnold E. Baragar

Historical Research Bulletins of the Nebraska Agricultural Experiment Station

During the past few years inquiries have been received regarding the cost of operation, efficiency, and performance of pressure gasoline and pressure kerosene stoves. Because of the method of operation and the use of gasoline as fuel, safety from fire and carbon monoxide has been frequently questioned. Not only is it necessary to have technical information about this type of appliance in order to compare it with other types but it is further important to know whether one type of burner is superior to another; whether one type of oven construction will give better results than another and in general …