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Full-Text Articles in Engineering
High-Power Biofuel Cells Based On Threedimensional Reduced Graphene Oxide/ Carbon Nanotube Micro-Arrays, Yin Song, Chunlei Wang
High-Power Biofuel Cells Based On Threedimensional Reduced Graphene Oxide/ Carbon Nanotube Micro-Arrays, Yin Song, Chunlei Wang
Department of Mechanical and Materials Engineering
Miniaturized enzymatic biofuel cells (EBFCs) with high cell performance are promising candidates for powering next-generation implantable medical devices. Here, we report a closed-loop theoretical and experimental study on a micro EBFC system based on three-dimensional (3D) carbon micropillar arrays coated with reduced graphene oxide (rGO), carbon nanotubes (CNTs), and a biocatalyst composite. The fabrication process of this system combines the top–down carbon microelectromechanical systems (C-MEMS) technique to fabricate the 3D micropillar array platform and bottom–up electrophoretic deposition (EPD) to deposit the reduced rGO/CNTs/enzyme onto the electrode surface. The Michaelis–Menten constant KM of 2.1 mM for glucose oxidase (GOx) on the …
Design Of High Temperature Ti–Al–Cr–V Alloys For Maximum Thermodynamic Stability Using Self-Organizing Maps, Rajesh Jha, George S. Dulikravich
Design Of High Temperature Ti–Al–Cr–V Alloys For Maximum Thermodynamic Stability Using Self-Organizing Maps, Rajesh Jha, George S. Dulikravich
Department of Mechanical and Materials Engineering
Data generated for the Ti–Al–Cr–V system of metallic alloys from our previous publication, where the composition of 102 alloys were computationally Pareto optimized with the objective of simultaneously maximizing the Young’s modulus and minimizing density for a range of temperatures, was the starting point of the current research, where compositions at different temperatures of these alloys were analyzed for phase stability in order to generate new data for compositions and volume fractions of stable phases at various temperatures. This resulted in a large dataset where a lot of data were still missing as all the phases are not stable at …
Design Of High Temperature Ti–Al–Cr–V Alloys For Maximum Thermodynamic Stability Using Self-Organizing Maps, Rajesh Jha, George S. Dulikravich
Design Of High Temperature Ti–Al–Cr–V Alloys For Maximum Thermodynamic Stability Using Self-Organizing Maps, Rajesh Jha, George S. Dulikravich
Department of Mechanical and Materials Engineering
Data generated for the Ti–Al–Cr–V system of metallic alloys from our previous publication, where the composition of 102 alloys were computationally Pareto optimized with the objective of simultaneously maximizing the Young’s modulus and minimizing density for a range of temperatures, was the starting point of the current research, where compositions at different temperatures of these alloys were analyzed for phase stability in order to generate new data for compositions and volume fractions of stable phases at various temperatures. This resulted in a large dataset where a lot of data were still missing as all the phases are not stable at …
Tribological Behavior Of Spark Plasma Sintered Aluminum-Graphene Composites At Room And Elevated Temperatures, Sara Rengifo, Cheng Zhang, Sandip Harimkar, Benjamin Boesl, Arvind Agarwal
Tribological Behavior Of Spark Plasma Sintered Aluminum-Graphene Composites At Room And Elevated Temperatures, Sara Rengifo, Cheng Zhang, Sandip Harimkar, Benjamin Boesl, Arvind Agarwal
Department of Mechanical and Materials Engineering
This study examines the role of Graphene nanoplatelets (GNPs) as a solid lubricant additive to aluminum. Pure Al and Al-2 vol % GNP pellets are sintered by Spark Plasma Sintering (SPS). Their tribological properties are evaluated by a ball-on-disk tribometer at room temperature (RT) and high temperature (200 °C). Al-2 vol % GNP composite displayed poor densification (91%) and low hardness, resulting in poor wear resistance as compared to pure Al. However GNP addition resulted in a lower coefficient of friction (COF) as compared to pure aluminum at both temperatures. The results demonstrated that GNPs contribute to reducing COF by …
Exergetic Optimization Of Power Generation Systems, Pouria Ahmadi, Halil S. Hamut, Ahmadreza Ghaffarizadeh, Pedram Hanafizadeh, Esmaiil Ghasemi
Exergetic Optimization Of Power Generation Systems, Pouria Ahmadi, Halil S. Hamut, Ahmadreza Ghaffarizadeh, Pedram Hanafizadeh, Esmaiil Ghasemi
Department of Mechanical and Materials Engineering
No abstract provided.
Mapping Chemical Selection Pathways For Designing Multicomponent Alloys: An Informatics Framework For Materials Design, Srinkant Srinivasan, Scott R. Broderick, Ruifeng Zhang, Amrita Mishra, Susan B. Sinnott, Surendra Saxena, James M. Lebeau, Krishna Rajan
Mapping Chemical Selection Pathways For Designing Multicomponent Alloys: An Informatics Framework For Materials Design, Srinkant Srinivasan, Scott R. Broderick, Ruifeng Zhang, Amrita Mishra, Susan B. Sinnott, Surendra Saxena, James M. Lebeau, Krishna Rajan
Department of Mechanical and Materials Engineering
A data driven methodology is developed for tracking the collective influence of the multiple attributes of alloying elements on both thermodynamic and mechanical properties of metal alloys. Cobalt-based superalloys are used as a template to demonstrate the approach. By mapping the high dimensional nature of the systematics of elemental data embedded in the periodic table into the form of a network graph, one can guide targeted first principles calculations that identify the influence of specific elements on phase stability, crystal structure and elastic properties. This provides a fundamentally new means to rapidly identify new stable alloy chemistries with enhanced high …
High Performance Li4ti5o12/Si Composite Anodes For Li-Ion Batteries, Chunhui Chen, Richa Agrawal, Chunlei Wang
High Performance Li4ti5o12/Si Composite Anodes For Li-Ion Batteries, Chunhui Chen, Richa Agrawal, Chunlei Wang
Department of Mechanical and Materials Engineering
Improving the energy capacity of spinel Li4Ti5O12 (LTO) is very important to utilize it as a high-performance Li-ion battery (LIB) electrode. In this work, LTO/Si composites with different weight ratios were prepared and tested as anodes. The anodic and cathodic peaks from both LTO and silicon were apparent in the composites, indicating that each component was active upon Li+ insertion and extraction. The composites with higher Si contents (LTO:Si = 35:35) exhibited superior specific capacity (1004 mAh·g−1) at lower current densities (0.22 A·g−1) but the capacity deteriorated at higher current densities. On the other hand, the electrodes with moderate Si …
Natural Convection Heat Transfer Under Constant Heat Flux Wall In A Nanofluid Filled Annulus Enclosure, S. M. Seyyedi, M. Dayyan, Soheil Soleimani, Esmaiil Ghasemi
Natural Convection Heat Transfer Under Constant Heat Flux Wall In A Nanofluid Filled Annulus Enclosure, S. M. Seyyedi, M. Dayyan, Soheil Soleimani, Esmaiil Ghasemi
Department of Mechanical and Materials Engineering
In this investigation, the Control Volume based Finite Element Method (CVFEM) is used to simulate the natural convection heat transfer of Cu–water nanofluid in an annulus enclosure. The Maxwell–Garnetts (MG) and Brinkman models are also employed to estimate the effect of thermal conductivity and viscosity of nanofluid. The governing parameters are the Rayleigh number, nanoparticle volume fraction and the aspect ratio (ratio of the outer radius to the inner one). Results are presented in the form of isotherms, streamlines, local and average Nusselt numbers. The results indicate that increment of the aspect ratio increases the value of average Nusselt number. …
Modeling And Simulation Of Enzymatic Biofuel Cells With Three-Dimensional Microelectrodes, Yin Song, Varun Penmatsa, Chunlei Wang
Modeling And Simulation Of Enzymatic Biofuel Cells With Three-Dimensional Microelectrodes, Yin Song, Varun Penmatsa, Chunlei Wang
Department of Mechanical and Materials Engineering
The enzymatic biofuel cells (EBFCs) are considered as an attractive candidate for powering future implantable medical devices. In this study, a computational model of EBFCs based on three-dimensional (3-D) interdigitated microelectrode arrays was conducted. The main focus of this research is to investigate the effect of different designs and spatial distributions of the microelectrode arrays on mass transport of fuels, enzymatic reaction rate, open circuit output potential and current density. To optimize the performance of the EBFCs, numerical simulations have been performed for cylindrical electrodes with various electrode heights and well widths. Optimized cell performance was obtained when the well …
Numerical Investigation Of The Effect Of Magnetic Field On Natural Convection In A Curved-Shape Enclosure, M. Shekholeslami, I. Hashim, Soheil Soleimani
Numerical Investigation Of The Effect Of Magnetic Field On Natural Convection In A Curved-Shape Enclosure, M. Shekholeslami, I. Hashim, Soheil Soleimani
Department of Mechanical and Materials Engineering
This investigation reports the magnetic field effect on natural convection heat transfer in a curved-shape enclosure. The numerical investigation is carried out using the control volume-based-finite element method (CVFEM). The numerical investigations are performed for various values of Hartmann number and Rayleigh number. The obtained results are depicted in terms of streamlines and isotherms which show the significant effects of Hartmann number on the fluid flow and temperature distribution inside the enclosure. Also, it was found that the Nusselt number decreases with an increase in the Hartmann number.