Shape Memory Alloy Capsule Micropump For Drug Delivery Applications, 2024 American University in Cairo
Shape Memory Alloy Capsule Micropump For Drug Delivery Applications, Youssef Mohamed Kotb
Theses and Dissertations
Implantable drug delivery devices have many benefits over traditional drug administration techniques and have attracted a lot of attention in recent years. By delivering the medication directly to the tissue, they enable the use of larger localized concentrations, enhancing the efficacy of the treatment. Passive-release drug delivery systems, one of the various ways to provide medication, are great inventions. However, they cannot dispense the medication on demand since they are nonprogrammable. Therefore, active actuators are more advantageous in delivery applications. Smart material actuators, however, have greatly increased in popularity for manufacturing wearable and implantable micropumps due to their high energy …
Properties Of Portland Cement Concrete Incorporating Basalt-Based Pozzolanic Cement, 2024 American University in Cairo
Properties Of Portland Cement Concrete Incorporating Basalt-Based Pozzolanic Cement, Rana Khalil
Theses and Dissertations
Over the last decade, the world's population has increased dramatically. Due to this growth, the demand for concrete and Portland cement, in return, have increased. Manufacturing of Portland cement is an energy-intensive process that, alone, contributes to about 8% of global CO2. For decades, efforts have been exerted to reduce the harmful environmental impacts of Portland cement by reducing its use in concrete as well as considering alternate binders that may fully or partially replace it. This study aims to assess the properties of concrete incorporating a novel basalt-based pozzolanic cement. To meet this objective, four sets of concrete mixtures …
Automated Workflow For Redox Potentials And Acidity Constants Calculations From Machine Learning Molecular Dynamics, 2024 aState Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen 361005, Fujian, China
Automated Workflow For Redox Potentials And Acidity Constants Calculations From Machine Learning Molecular Dynamics, Feng Wang, Jun Cheng
Journal of Electrochemistry
Redox potentials and acidity constants are key properties for evaluating the performance of energy materials. To achieve computational design of new generation of energy materials with higher performances, computing redox potentials and acidity constants with computational chemistry have attracted lots of attention. However, many works are done by using implicit solvation models, which is difficult to be applied to complex solvation environments due to hard parameterization. Recently, ab initio molecular dynamics (AIMD) has been applied to investigate real electrolytes with complex solvation. Furthermore, AIMD based free energy calculation methods have been established to calculate these physical chemical properties accurately. However, …
Joint Time-Frequency Analysis: Taking Charge Penetration Depth And Current Spatial Distribution In The Single Pore As An Example, 2024 Institute for Sustainable Energy/College of Science, Shanghai University, Shanghai 201800, China
Joint Time-Frequency Analysis: Taking Charge Penetration Depth And Current Spatial Distribution In The Single Pore As An Example, Nan Wang, Qiu-An Huang, Wei-Heng Li, Yu-Xuan Bai, Jiu-Jun Zhang
Journal of Electrochemistry
In recent years, joint time-frequency analysis has once again become a research hotspot. Supercapacitors have high power density and long service life, however, in order to balance between power density and energy density, two key factors need to be considered: (i) the specific surface area of the porous matrix; (ii) the electrolyte accessibility to the intra-pore space of porous carbon matrix. Electrochemical impedance spectra are extensively used to investigate charge penetration ratio and charge storage mechanism in the porous electrode for capacitance energy storage. Furthermore, similar results could be obtained by different methods such as stable-state analysis in the frequency …
A Study On High-Frequency Bending Fatigue, Microhardness, Tensile Strength, And Microstructure Of Parts Made Using Atomic Diffusion Additive Manufacturing (Adam) And Additive Friction Stir Deposition (Afsd), 2024 Louisiana State University and Agricultural and Mechanical College
A Study On High-Frequency Bending Fatigue, Microhardness, Tensile Strength, And Microstructure Of Parts Made Using Atomic Diffusion Additive Manufacturing (Adam) And Additive Friction Stir Deposition (Afsd), Hamed Ghadimi
LSU Doctoral Dissertations
This dissertation reports the findings of several studies on the mechanical and microstructural properties of parts made using atomic diffusion additive manufacturing (ADAM) and additive friction stir deposition (AFSD). The design of a small-sized bending-fatigue test specimen for an ultrasonic fatigue testing system is reported in Chapter 1. The design was optimized based on the finite element analysis and analytical solution. The stress–life (S–N) curve is obtained for Inconel alloy 718. Chapter 2 presents the findings of ultrasonic bending-fatigue and tensile tests carried out on the ADAM test specimens. The S-N curves were created in the very high-cycle fatigue regime. …
Residual Stress Generation In Additive Manufacturing Of Complex Lattice Geometries, 2024 Wright State University
Residual Stress Generation In Additive Manufacturing Of Complex Lattice Geometries, Katie Bruggeman, Nathan Klingbeil, Anthony N. Palazotto
Faculty Publications
Residual stresses developed during additive manufacturing (AM) can influence the mechanical performance of structural components in their intended applications. In this study, thermomechanical residual stress simulations of the laser powder bed fusion (LPBF) process are conducted for both simplified (plate and cube-shaped) geometries as well as five complex lattice geometries fabricated with Inconel 718. These simulations are conducted with the commercial software package Simufact Additive©, which uses a nonlinear finite element analysis and layer-by-layer averaging approach in determining residual stresses. To verify the efficacy of the Simufact Additive© simulations, numerical results for the plate and cube-shape geometries are analyzed for …
The Top Ten Scientific Questions In Electrochemistry, 2024 Chinese Chemical Society | Xiamen University
The Top Ten Scientific Questions In Electrochemistry, Chinese Society Of Electrochemistry
Journal of Electrochemistry
No abstract provided.
Stability Of A Solid Oxide Cell Stack Under Direct Internal-Reforming Of Hydrogen-Blended Methane, 2024 Key Laboratory of Advanced Fuel Cells and Electrolyzers cell Technology of Zhejiang Province, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, Zhejiang, China
Stability Of A Solid Oxide Cell Stack Under Direct Internal-Reforming Of Hydrogen-Blended Methane, Ya-Fei Tang, An-Qi Wu, Bei-Bei Han, Hua Liu, Shan-Jun Bao, Wang-Lin Lin, Ming Chen, Wan-Bing Guan, Subhash C. Singhal
Journal of Electrochemistry
In this work, the long-term stability and degradation mechanism of a direct internal-reforming solid oxide fuel cell stack (IR-SOFC stack) using hydrogen-blended methane steam reforming were investigated. An overall degradation rate of 2.3%·kh–1 was found after the stack was operated for 3000 hours, indicating a good long-term stability. However, the voltages of the two cells in the stack were increased at the rates of 3.38 mV·kh–1 and 3.78 mV·kh–1, while the area specific resistances of the three metal interconnects in the stack were increased to 0.276 Ω·cm2, 0.254 Ω·cm2 and 0.249 Ω·cm2 …
Rational Design Of Heterostructured Nanomaterials For Accelerating Electrocatalytic Hydrogen Evolution Reaction Kinetics In Alkaline Media, 2024 Shanghai Key Laboratory for R&D and Application of Metallic Functional Materials, Institute of New Energy for Vehicles, School of Materials Science and Engineering, Tongji University, Shanghai 201804, China
Rational Design Of Heterostructured Nanomaterials For Accelerating Electrocatalytic Hydrogen Evolution Reaction Kinetics In Alkaline Media, Hai-Bin Ma, Xiao-Yan Zhou, Jia-Yi Li, Hong-Fei Cheng, Ji-Wei Ma
Journal of Electrochemistry
Owing to the merits of high energy density, as well as clean and sustainable properties, hydrogen has been deemed to be a prominent alternative energy to traditional fossil fuels. Electrocatalytic hydrogen evolution reaction (HER) has been considered to be mostly promising for achieving green hydrogen production, and has been widely studied in acidic and alkaline solutions. In particular, HER in alkaline media has high potential to achieve large-scale hydrogen production because of the increased durability of electrode materials. However, for the currently most prominent catalyst Pt, its HER kinetics in an alkaline solution is generally 2–3 orders lower than that …
Structured Invariant Subspace And Decomposition Of Systems With Time Delays And Uncertainties, 2024 Southern Illinois University Edwardsville
Structured Invariant Subspace And Decomposition Of Systems With Time Delays And Uncertainties, Huan Phan-Van, Keqin Gu
SIUE Faculty Research, Scholarship, and Creative Activity
This article discusses invariant subspaces of a matrix with a given partition structure. The existence of a nontrivial structured invariant subspace is equivalent to the possibility of decomposing the associated system with multiple feedback blocks such that the feedback operators are subject to a given constraint. The formulation is especially useful in the stability analysis of time-delay systems using the Lyapunov-Krasovskii functional approach where computational efficiency is essential in order to achieve accuracy for large scale systems. The set of all structured invariant subspaces are obtained (thus all possible decompositions are obtained as a result) for the coupled differential-difference equations …
Me-Em Enewsbrief, December 2023, 2024 Michigan Technological University
Me-Em Enewsbrief, December 2023, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University
Department of Mechanical Engineering-Engineering Mechanics eNewsBrief
No abstract provided.
Materials Of Lightweight Concrete Research, 2024 The University of Akron
Materials Of Lightweight Concrete Research, Meganne Chapman, Kathryn Burns, John Grubb
Williams Honors College, Honors Research Projects
The objectives for this research project are to explore options for innovative and sustainable materials in lightweight concrete. Various materials including granite powder, hydrated lime, latex, and recycled glass beads will be used in the concrete testing for this project. The question the team wants to answer is how these additives affect the concrete’s mechanical properties. Weekly mix designs will be performed, and control cylinders will be compared to experimental cylinders. Compression and tensile testing will also be performed to further aid the research. The motivation for performing this research is to aid mix development for the University of Akron …
External Direct Sum Invariant Subspace And Decomposition Of Coupled Differential-Difference Equations, 2024 Southern Illinois University Edwardsville
External Direct Sum Invariant Subspace And Decomposition Of Coupled Differential-Difference Equations, Keqin Gu, Huan Phan-Van
SIUE Faculty Research, Scholarship, and Creative Activity
This article discusses the invariant subspaces that are restricted to be external direct sums. Some existence conditions are presented that facilitate finding such invariant subspaces. This problem is related to the decomposition of coupled differential-difference equations, leading to the possibility of lowering the dimensions of coupled differential-difference equations. As has been well documented, lowering the dimension of coupled differential-difference equations can drastically reduce the computational time needed in stability analysis when a complete quadratic Lyapunov-Krasovskii functional is used. Most known ad hoc methods of reducing the order are special cases of this formulation.
Analysis Of Marine Zone Management In Disputed Island Territories, 2023 Institut Teknologi Sepuluh Nopember, Surabaya
Analysis Of Marine Zone Management In Disputed Island Territories, Khomsin Khomsin, Danar Guruh Pratomo, Ayu Isnania Zahra
Journal of Environmental Science and Sustainable Development
Indonesia has 17,204 islands registered, named, and coordinated by Geospatial Information Agency (BIG). The number of islands can threaten maritime boundary disputes between provinces, districts, and cities. One of the disputes is the claim over Pulau Tujuh, which is mutually contested for ownership by the Province of Bangka Belitung and the Province of Riau Islands. This study aims to analyze the marine management zone of the Pulau Tujuh claim. It is carried out using the cartometric method. This study of regional boundaries refers to the Regulation of The Minister of Home Affairs of The Republic of Indonesia 141 of 2017, …
Reducing Food Scarcity: The Benefits Of Urban Farming, 2023 Brigham Young University
Reducing Food Scarcity: The Benefits Of Urban Farming, S.A. Claudell, Emilio Mejia
Journal of Nonprofit Innovation
Urban farming can enhance the lives of communities and help reduce food scarcity. This paper presents a conceptual prototype of an efficient urban farming community that can be scaled for a single apartment building or an entire community across all global geoeconomics regions, including densely populated cities and rural, developing towns and communities. When deployed in coordination with smart crop choices, local farm support, and efficient transportation then the result isn’t just sustainability, but also increasing fresh produce accessibility, optimizing nutritional value, eliminating the use of ‘forever chemicals’, reducing transportation costs, and fostering global environmental benefits.
Imagine Doris, who is …
Multi-Mode Regulation Of The Drying Process Of Industrial Gas, 2023 Tashkent State Technical University, Tashkent city, Republic of Uzbekistan
Multi-Mode Regulation Of The Drying Process Of Industrial Gas, Isamidin Xakimovich Sidikov Pr, Nashvandova Gulruxsor Murot Qizi Phd
Technical science and innovation
Currently, much attention is paid to the issue of energy efficiency of gas processing enterprises. The continuous growth of world prices for energy resources requires constant improvement of the management system, providing the most optimal conditions for the flow of technological processes. A conceptual model of the heat-mass transfer process occurring in the absorber as an object of research has been developed, which characterizes the relationship of the variables involved in the drying process of natural gas, control, measurable and immeasurable, as well as controlled parameters have been selected, which are used to develop and study a mathematical model of …
An In-Situ Raman Spectroscopic Study On The Interfacial Process Of Carbonate-Based Electrolyte On Nanostructured Silver Electrode, 2023 State Key Laboratory of Physical Chemistry of Solid Surfaces, Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China
An In-Situ Raman Spectroscopic Study On The Interfacial Process Of Carbonate-Based Electrolyte On Nanostructured Silver Electrode, Yu Gu, Yuan-Fei Hu, Wei-Wei Wang, En-Ming You, Shuai Tang, Jian-Jia Su, Jun Yi, Jia-Wei Yan, Zhong-Qun Tian, Bing-Wei Mao
Journal of Electrochemistry
The solid-electrolyte interphase (SEI) plays a key role in anodes for rechargeable lithium-based battery technologies. However, a thorough understanding in the mechanisms of SEI formation and evolution remains a major challenge, hindering the rapid development and wide applications of Li-based batteries. Here, we devise a borrowing surface-enhanced Raman scattering (SERS) activity strategy by utilizing a size optimized Ag nanosubstrate to in-situ monitor the formation and evolution of SEI, as well as its structure and chemistry in an ethylene carbonate-based electrolyte. To ensure a reliable in-situ SERS investigation, we designed a strict air-tight Raman cell with a three-electrode configuration. Based on …
Electrochemical Performance Of Porous Ceramic Supported Tubular Solid Oxide Electrolysis Cell, 2023 School of Materials Science and Hydrogen Energy, Foshan University, Foshan 528000, China
Electrochemical Performance Of Porous Ceramic Supported Tubular Solid Oxide Electrolysis Cell, Heng-Ji Wang, Wen-Guo Chen, Zhou-Yi Quan, Kai Zhao, Yi-Fei Sun, Min Chen, Ogenko Volodymyr
Journal of Electrochemistry
Solid oxide electrolysis cell (SOEC) is an efficient and clean energy conversion technology that can utilize electricity obtained from renewable resources, such as solar, wind, and geothermal energy to electrolyze water and produce hydrogen. The conversion of abundant intermittent energy to hydrogen energy would facilitate the efficient utilization of energy resources. SOEC is an all-ceramic electrochemical cell that operates in the intermediate to high temperature range of 500–750 ℃. Compared with traditional low temperature electrolysis technology (e.g., alkaline or proton exchange membrane cells operating at ~100 ℃), the high-temperature SOEC can increase the electrolysis efficiency from 80% to ~100%, providing …
Nitrogen-Doped Graphite Felt On The Performance Of Aqueous Quinone-Based Redox Flow Batteries, 2023 State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, North China Electric Power University, Beijing 102206, China
Nitrogen-Doped Graphite Felt On The Performance Of Aqueous Quinone-Based Redox Flow Batteries, Heng Zhang, Li-Xing Xia, Shan Jiang, Fu-Zhi Wang, Zhan-Ao Tan
Journal of Electrochemistry
Modification of electrode is vitally important for achieving high energy efficiency in aqueous quinone-based redox flow batteries (AQRFBs). The modification of graphite felt (GF) was carried out by means of urea hydrothermal reaction, and simultaneously, the effects of hydrothermal reaction time on the functional groups and surface structure of nitrogen-doped graphite felt were studied. The surface morphology and defect, element content and surface chemical state of the modified electrode were characterized by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) test, Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). The electrochemical performance of the modified electrodes was evaluated by cyclic voltammetry, electrochemical impedance …
Robust Gasification Trial Results For A Variety Of Difficult-To-Recycle Packaging-Related Materials, 2023 University of Florida
Robust Gasification Trial Results For A Variety Of Difficult-To-Recycle Packaging-Related Materials, Bruce A. Welt
Journal of Applied Packaging Research
Currently, recycling requires nearly absolute sorting of materials to accommodate the limited capabilities of existing recycling infrastructure. Whether a material is “recyclable” depends more on the method of recycling than the material itself. Our dependence upon sorting has limited success of recycling and has stifled our ability to achieve circular economy sustainability with plastic packaging materials. Our dependence upon sorting is rooted in our material-specific recycling processes. However, newer robust recycling processes are commercially available that reduce or eliminate the need to sort waste, and can convert mixed waste into primary feedstock chemicals, such as methanol for subsequent manufacture of …