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Full-Text Articles in Engineering

Searching Govinfo.Gov/, Bert Chapman Mar 2024

Searching Govinfo.Gov/, Bert Chapman

Libraries Faculty and Staff Presentations

This U.S. Government Publishing Office (GPO) database provides access to information legal, legislative, and regulatory information produced on multiple subjects by the U.S. Government. Content includes congressional bills, congressional committee hearings and prints (studies), reports on legislation, the text of laws, regulations, and executive orders and multiple U.S. Government information resources covering subjects from accounting to zoology.

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Scrutinizing The Adoption Of Smart Contracts In The Mena Region’S Construction Industry, Ahmed Gouda Mohamed Mar 2024

Scrutinizing The Adoption Of Smart Contracts In The Mena Region’S Construction Industry, Ahmed Gouda Mohamed

Civil Engineering

The construction industry embodies a paramount role in the economic growth of various nations, including the Middle East and North Africa (MENA) region. Despite its significance, the industry faces construction disputes and payment issues, inducing financial losses and project postponements. Consequently, the construction industry has mutated smart contracts to enhance operational efficiency, which automates contract management tasks and offers perks, including transparency and efficiency. However, the adoption of smart contracts in the MENA construction sector remains limited, and the region lacks thorough research on this topic. This study addresses this gap by examining the level of cognizance and apprehension of …

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Maximizing Ev Profit And Grid Stability Through Virtual Power Plant Considering V2g, A. Selim Türkoğlu, H. Cihan Güldorum, Ibrahim Sengor Mar 2024

Maximizing Ev Profit And Grid Stability Through Virtual Power Plant Considering V2g, A. Selim Türkoğlu, H. Cihan Güldorum, Ibrahim Sengor

Electrical & Electronic Engineering

The electrification of transportation through the widespread adoption of electric vehicles (EVs) has raised substantial concerns within the realm of power grid operations. This concern predominantly stems from the elevated electricity demand brought about by the surging population of EVs, consequently exerting strain on the power grid infrastructure which can be reduced with vehicle-to-grid (V2G) technology integration. To address this issue, this paper delves further into the realm of grid integration by introducing a Virtual Power Plant (VPP) concept to enhance the synergy between EVs and power grid. This study aims to compare different realistic objectives, ranging from total active …

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Understanding Lightning Damage Formation In A Carbon-Epoxy Pultruded Rod Stitched Efficient Unitized Structure (Prseus) Composite, Dounia Boushab, Aniket Mote, Khari Harrison, Juhyeong Lee, Charles U. Pittman Jr., Thomas E. Lacy Jr. Mar 2024

Understanding Lightning Damage Formation In A Carbon-Epoxy Pultruded Rod Stitched Efficient Unitized Structure (Prseus) Composite, Dounia Boushab, Aniket Mote, Khari Harrison, Juhyeong Lee, Charles U. Pittman Jr., Thomas E. Lacy Jr.

Mechanical and Aerospace Engineering Faculty Publications

Lightning damage to composite aircraft structures results from a concurrent and sequential interaction between arc discharge multi-physics and the anisotropic electrical and thermal composite properties. In this study, the impact of nominal 50 and 125 kA lightning strikes on damage formation in a carbon-epoxy Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS) was investigated. A combination of visual inspection, ultrasonic phased array testing, destructive sectioning, and various microscopy techniques was employed to characterize the damage. Localized damage, including severe matrix decomposition, melting of polyester warp-knitting yarns, fiber splitting, and large-scale delamination, was confined to the immediate vicinity of the lightning attachment …

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Synergistic Preparation And Application In Pcu Of Α‑Calcium Sulfate Hemihydrate Whiskers From Phosphogypsum And Electrolytic Manganese Residue, Ting Wang, Xuan Ke, Jia Li, Ying Wang, Weiwei Guan, Xia Sha, Chenjing Yang, Tian Zhang Mar 2024

Synergistic Preparation And Application In Pcu Of Α‑Calcium Sulfate Hemihydrate Whiskers From Phosphogypsum And Electrolytic Manganese Residue, Ting Wang, Xuan Ke, Jia Li, Ying Wang, Weiwei Guan, Xia Sha, Chenjing Yang, Tian Zhang

Department of Civil and Environmental Engineering: Faculty Publications

The α-calcium sulfate hemihydrate whiskers (α-CSHWs) were first prepared using phosphogypsum (PG) and electrolytic manganese residue (EMR) as raw materials for coating urea, demonstrating excellent controlled-release properties. The effects of different reaction conditions on α-CSHWs, achieved by optimizing the reaction time, the concentrations of NH4+, Mn2+, and other factors, were discussed. Results showed that when the EMR content was 25 wt%, the reaction temperature was 100 °C, and the reaction time was 3 h, α-CSHWs with a length-to-diameter ratio of 39 were obtained. Through experiments and density functional theory (DFT), the mechanism of α-CSHWs preparation …

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Parametric Analysis Of Co2 Hydrogenation Via Fischer-Tropsch Synthesis: A Review Based On Machine Learning For Quantitative Assessment, Jing Hu, Yixao Wang, Xiyue Zhang, Yunshan Wang, Gang Yang, Lufang Shi, Yong Sun Mar 2024

Parametric Analysis Of Co2 Hydrogenation Via Fischer-Tropsch Synthesis: A Review Based On Machine Learning For Quantitative Assessment, Jing Hu, Yixao Wang, Xiyue Zhang, Yunshan Wang, Gang Yang, Lufang Shi, Yong Sun

Research outputs 2022 to 2026

This review focuses on the parametric impacts upon conversion and selectivity during CO2 hydrogenation via Fischer-Tropsch (FT) synthesis using iron-based catalyst to provide quantitative evaluation. Using all collected data from reported literatures as training dataset via artificial neural networks (ANNs) in TensorFlow, three categorized parameters (namely: operational, catalyst informatic and mass transfer) were deployed to assess their impacts upon conversions (CO2) and selectivity. The lump kinetic power expressions among literature reports were compared, and the best fit model is the one that was proposed by this work without arbitrarily assuming power values of individual partial pressure (CO and H2). More …

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On The Use Of Machine Learning And Data-Transformation Methods To Predict Hydration Kinetics And Strength Of Alkali-Activated Mine Tailings-Based Binders, Sahil Surehali, Taihao Han, Jie Huang, Aditya Kumar, Narayanan Neithalath Mar 2024

On The Use Of Machine Learning And Data-Transformation Methods To Predict Hydration Kinetics And Strength Of Alkali-Activated Mine Tailings-Based Binders, Sahil Surehali, Taihao Han, Jie Huang, Aditya Kumar, Narayanan Neithalath

Electrical and Computer Engineering Faculty Research & Creative Works

The escalating production of mine tailings (MT), a byproduct of the mining industry, constitutes significant environmental and health hazards, thereby requiring a cost-effective and sustainable solution for its disposal or reuse. This study proposes the use of MT as the primary ingredient (≥70%mass) in binders for construction applications, thereby ensuring their efficient upcycling as well as drastic reduction of environmental impacts associated with the use of ordinary Portland cement (OPC). The early-age hydration kinetics and compressive strength of MT-based binders are evaluated with an emphasis on elucidating the influence of alkali activation parameters and the amount of slag or cement …

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Evaluation Of Infrared Thermography Dataset For Delamination Detection In Reinforced Concrete Bridge Decks, Eberechi Ichi, Sattar Dorafshan Mar 2024

Evaluation Of Infrared Thermography Dataset For Delamination Detection In Reinforced Concrete Bridge Decks, Eberechi Ichi, Sattar Dorafshan

Civil Engineering Faculty Publications

Structural health monitoring and condition assessment of existing bridge decks is a growing challenge. Conventional manned inspections are costly, labor-intensive, and often risky to execute. Sub-surface delamination, a leading cause of deck replacement, can be autonomously and objectively detected using infrared thermography (IRT) data with developed deep learning AI models to address some of the limitations associated with manned inspection. As one of the most promising classifiers, deep convolutional neural networks (DCNNs) have not been utilized to their fullest potential for delamination detection, arguably due to the scarcity of realistic ground truth datasets. In this study, a common encoder–decoder semantic …

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Unmanned Aircraft Systems In Road Assessment: A Novel Approach To The Pavement Condition Index And Vizir Methodologies, Diana Marcela Ortega Rengifo, Jose Capa Salinas, Javier Alexander Perez Caicedo, Manuel Alejandro Rojas Manzano Mar 2024

Unmanned Aircraft Systems In Road Assessment: A Novel Approach To The Pavement Condition Index And Vizir Methodologies, Diana Marcela Ortega Rengifo, Jose Capa Salinas, Javier Alexander Perez Caicedo, Manuel Alejandro Rojas Manzano

Purdue University Libraries Open Access Publishing Fund

This paper presents an innovative approach to road assessment, focusing on enhancing the Pavement Condition Index (PCI) and Visión Inspection de Zones et Itinéraires Á Risque (VIZIR) methodologies by integrating Unmanned Aircraft System (UAS) technology. The research was conducted in an urban setting, utilizing a UAS to capture high-resolution imagery, which was subsequently processed to generate detailed orthomosaics of road surfaces. This study critically analyzed the discrepancies between traditional field measurements and UAS-derived data in pavement condition assessment. The study findings demonstrate that photogrammetry-derived data from UAS offer at least similar or, in some cases, improved information on the collection …

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Miniature Optical Fiber Fabry-Perot Interferometer Based On A Single-Crystal Metal-Organic Framework For The Detection And Quantification Of Benzene And Ethanol At Low Concentrations In Nitrogen Gas, Farhan Mumtaz, Bohong Zhang, Narasimman Subramaniyam, Mohammad Roman, Peter Holtmann, Abhishek Prakash Hungund, Ryan O'Malley, Thomas M. Spudich, Michael Davis, Rex E. Gerald, Jie Huang Mar 2024

Miniature Optical Fiber Fabry-Perot Interferometer Based On A Single-Crystal Metal-Organic Framework For The Detection And Quantification Of Benzene And Ethanol At Low Concentrations In Nitrogen Gas, Farhan Mumtaz, Bohong Zhang, Narasimman Subramaniyam, Mohammad Roman, Peter Holtmann, Abhishek Prakash Hungund, Ryan O'Malley, Thomas M. Spudich, Michael Davis, Rex E. Gerald, Jie Huang

Electrical and Computer Engineering Faculty Research & Creative Works

This study reports for the first time, to the best of our knowledge, a real-time detection of ultralow-concentration chemical gases using fiber-optic technology, combining a miniaturized Fabry-Perot interferometer (FPI) with metal-organic frameworks (MOFs). The sensor consists of a short and thick-walled silica capillary segment spliced to a lead-in single-mode fiber (SMF), housing a tiny single crystal of HKUST-1 MOF, imparting chemo selectivity features. Ethanol and benzene gases were tested, resulting in a shift in the FPI interference signal. The sensor demonstrated high sensitivity, detecting ethanol gas concentrations (EGCs) with a sensitivity of 0.428 nm/ppm between 24.9 and 40.11 ppm and …

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Resolving The Nanoscale Structure Of Β-Sheet Peptide Self-Assemblies Using Single-Molecule Orientation–Localization Microscopy, Weiyan Zhou, Conor L. O'Neill, Tianben Ding, Oumeng Zhang, Jai S. Rudra, Matthew D. Lew Mar 2024

Resolving The Nanoscale Structure Of Β-Sheet Peptide Self-Assemblies Using Single-Molecule Orientation–Localization Microscopy, Weiyan Zhou, Conor L. O'Neill, Tianben Ding, Oumeng Zhang, Jai S. Rudra, Matthew D. Lew

Electrical & Systems Engineering Publications and Presentations

Synthetic peptides that self-assemble into cross-β fibrils are versatile building blocks for engineered biomaterials due to their modularity and biocompatibility, but their structural and morphological similarities to amyloid species have been a long-standing concern for their translation. Further, their polymorphs are difficult to characterize using spectroscopic and imaging techniques that rely on ensemble averaging to achieve high resolution. Here, we utilize Nile red (NR), an amyloidophilic fluorogenic probe, and single-molecule orientation-localization microscopy (SMOLM) to characterize fibrils formed by the designed amphipathic enantiomers KFE8L and KFE8D and the pathological amyloid-beta peptide Aβ42. Importantly, NR SMOLM reveals the helical (bilayer) …

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Spatiotemporal Reaction Dynamics Control In Two-Photon Polymerization For Enhancing Writing Characteristics, Aofei Mao, Sarah Fess, Nada Kraiem, P. Li, Zhipeng P. Wu, Qiuchi Zhu, Xi Huang, Peixun Fan, Bai Cui, Jean-Francois Silvain, Suxing Hu, Mitchell Anthamatten, Sean P. Regan, David Harding, Yongfeng Lu Mar 2024

Spatiotemporal Reaction Dynamics Control In Two-Photon Polymerization For Enhancing Writing Characteristics, Aofei Mao, Sarah Fess, Nada Kraiem, P. Li, Zhipeng P. Wu, Qiuchi Zhu, Xi Huang, Peixun Fan, Bai Cui, Jean-Francois Silvain, Suxing Hu, Mitchell Anthamatten, Sean P. Regan, David Harding, Yongfeng Lu

Department of Electrical and Computer Engineering: Faculty Publications

Since 2001, 3D microfabrication based on two-photon polymerization (TPP) has drawn extensive attention and interest in biology, optics, photonics, material science, and high-energy physics. The in-volume fabrication capability due to the threshold behavior of two-photon absorption enables TPP higher flexibility compared with other nanofabrication techniques. However, as determined by the in-volume fabrication feature as well as various reaction dynamics, the writing characteristics of TPP, such as throughput, accuracy, surface quality, and fabrication capability, are still limited. Herein, a comprehensive study is performed on the spatiotemporal behavior of reaction dynamics during TPP fabrication, mainly focusing on spatiotemporal characteristics of radical diffusion, …

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6d Single-Fluorogen Orientation-Localization Microscopy For Elucidating The Architecture Of Beta-Sheet Assemblies And Biomolecular Condensates, Tingting Wu, Weiyan Zhou, Jai S. Rudra, Rohit V. Pappu, Matthew D. Lew Mar 2024

6d Single-Fluorogen Orientation-Localization Microscopy For Elucidating The Architecture Of Beta-Sheet Assemblies And Biomolecular Condensates, Tingting Wu, Weiyan Zhou, Jai S. Rudra, Rohit V. Pappu, Matthew D. Lew

Electrical & Systems Engineering Publications and Presentations

We develop six-dimensional single-molecule orientation-localization microscopy (SMOLM) to measure the 3D positions and 3D orientations simultaneously of single fluorophores. We show how careful optimization of phase and polarization modulation components can encode phase, polarization, and angular spectrum information from each fluorescence photon into a microscope’s dipole-spread function. We used the transient binding and blinking of Nile red (NR) to characterize the helical structure of fibrils formed by designed amphipathic peptides, KFE8L and KFE8D, and the pathological amyloid-beta peptide Aβ42. We also deployed merocyanine 540 to uncover the interfacial architectures of biomolecular condensates.

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Synthesis And Energetic Characterization Of Borane-Amines On High-Nitrogen Heterocycles, Randy Lin, Nicholas F. Scherschel, Matthias Zeller, Stephen G. Hamlin, Madison Snyder, Steven Son, P. Veeraraghavan Ramachandran, Davin G. Piercey Mar 2024

Synthesis And Energetic Characterization Of Borane-Amines On High-Nitrogen Heterocycles, Randy Lin, Nicholas F. Scherschel, Matthias Zeller, Stephen G. Hamlin, Madison Snyder, Steven Son, P. Veeraraghavan Ramachandran, Davin G. Piercey

Purdue University Libraries Open Access Publishing Fund

Borane-amines have garnered attention over the last several decades in a variety of applications, ranging from hydrogen storage materials to hypergolic fuel systems. An investigation into the synthesis of borane-amines with high-nitrogen content heterocycles was undertaken in this work. Borane-amines were formed by the reaction of BH3·Me2S in tetrahydrofuran (THF) with the requisite nitrogen-containing heterocycle and isolated by placing the crude reaction mixture in hexanes to precipitate the product. X-ray crystallography, thermogravimetric analysis (TGA), high resolution mass spectroscopy (HRMS), 1H NMR, 13C NMR, and 11B NMR were utilized for product characterization, while impact and friction sensitivity testing were conducted to …

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Comparing Task Graph Scheduling Algorithms: An Adversarial Approach, Jared Coleman, Bhaskar Krishnamachari Mar 2024

Comparing Task Graph Scheduling Algorithms: An Adversarial Approach, Jared Coleman, Bhaskar Krishnamachari

Computer Science Faculty Works

Scheduling a task graph representing an application over a heterogeneous network of computers is a fundamental problem in distributed computing. It is known to be not only NP-hard but also not polynomial-time approximable within a constant factor. As a result, many heuristic algorithms have been proposed over the past few decades. Yet it remains largely unclear how these algorithms compare to each other in terms of the quality of schedules they produce. We identify gaps in the traditional benchmarking approach to comparing task scheduling algorithms and propose a simulated annealing-based adversarial analysis approach called PISA to help address them. We …

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Effect Of The Filler Morphology On The Crystallization Behavior And Dielectric Properties Of The Polyvinylidene Fluoride-Based Composite, Suzana Filipović, Nina Obradović, Cole Corlett, William G. Fahrenholtz, Martin Rosenschon, Ekkehard Füglein, Radovan Dojčilović, Dragana Tošić, Jovana Petrović, Antonije Đorđević, Branislav Vlahović, Vladimir B. Pavlović Mar 2024

Effect Of The Filler Morphology On The Crystallization Behavior And Dielectric Properties Of The Polyvinylidene Fluoride-Based Composite, Suzana Filipović, Nina Obradović, Cole Corlett, William G. Fahrenholtz, Martin Rosenschon, Ekkehard Füglein, Radovan Dojčilović, Dragana Tošić, Jovana Petrović, Antonije Đorđević, Branislav Vlahović, Vladimir B. Pavlović

Materials Science and Engineering Faculty Research & Creative Works

Ceramic/polymer composites can be chemically stable, mechanically strong, and flexible, which make them candidates for electric devices, such as pressure or temperature sensors, energy storage or harvesting devices, actuators, and so forth. Depending on the application, various electrical properties are of importance. Polymers usually have low dielectric permittivity, but increased dielectric permittivity can be achieved by the addition of the ceramic fillers with high dielectric constant. With the aim to enhance dielectric properties of the composite without loss of flexibility, 5 wt.% of BaTiO3-Fe2O3 powder was added into a polyvinylidene fluoride matrix. The powder was …

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After A Wildfire: Water Safety Considerations For Agriculture Water Systems, Andrew J. Whelton, P. Coelho Mar 2024

After A Wildfire: Water Safety Considerations For Agriculture Water Systems, Andrew J. Whelton, P. Coelho

Resilience to Emergencies and Disasters

No abstract provided.

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Development Of Quantitative Structure Activity Relationships (Qsars) For Predicting The Aggregation Of Tio2 Nanoparticles Under Favorable Conditions, Jaewoong Lee Mar 2024

Development Of Quantitative Structure Activity Relationships (Qsars) For Predicting The Aggregation Of Tio2 Nanoparticles Under Favorable Conditions, Jaewoong Lee

Department of Civil and Environmental Engineering: Faculty Publications

This study developed multi-linear regression (MLR) quantitative structure-activity relationships (QSARs) to predict n-TiO2 aggregation in the presence of high concentrations of representative emerging organic contaminants (EOCs), which presented favorable conditions to interaction with n-TiO2. The largest diameter change (Δ 517 nm at 0 h and Δ 1164 nm at 12 h) of n-TiO2 was observed by estrone, while the smallest diameter change (Δ -114 nm at 0 h and – 4 nm at 12 h) was observed by lincomycin during experimental periods. In addition, the zeta potential changes of n-TiO2 were …

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A Deep Learning Convolutional Neural Network For Antenna Near-Field Prediction And Surrogate Modeling, Md Rayhan Khan, Constantinos L. Zekios, Shubhendu Bhardwaj, Stavros V. Georgakopoulos Mar 2024

A Deep Learning Convolutional Neural Network For Antenna Near-Field Prediction And Surrogate Modeling, Md Rayhan Khan, Constantinos L. Zekios, Shubhendu Bhardwaj, Stavros V. Georgakopoulos

Department of Electrical and Computer Engineering: Faculty Publications

This study investigates the use of deep learning techniques for building a generalized surrogate model that can accurately and very efficiently predict antenna performance parameters. Notably, we focus on applications where a substantial amount of simulation time is required and prior data is available for deep learning use. Specifically, for these applications, we introduce deep learning models that efficiently and reliably model the near-field of the antenna. These models, in turn, accurately predict far-field properties and essential antenna metrics, such as the reflection coefficient. To demonstrate the efficiency of our method, the widely used rectangular patch antenna is considered, encompassing …

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Feature Engineering And Supervised Machine Learning To Forecast Biogas Production During Municipal Anaerobic Co-Digestion, Hunter W. Schroer, Craig L. Just Mar 2024

Feature Engineering And Supervised Machine Learning To Forecast Biogas Production During Municipal Anaerobic Co-Digestion, Hunter W. Schroer, Craig L. Just

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Municipalities with excess anaerobic digestion capacity accept offsite wastes for co-digestion to meet sustainability goals and create more biogas. Despite the benefits inherent to co-digestion, the temporal and compositional heterogeneity of external waste streams creates operational challenges that lead to upsets or conservative co-digestion. Given the complex microbial bioprocesses occurring during anaerobic digestion, prediction and modeling of the outcomes can be challenging, and machine learning has the potential to improve understanding and control of co-digestion processes. Biogas flows are a surrogate for process health, and here, we predicted biogas production from historical data collected by a water resource recovery facility …

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Highly Efficient Dopamine Sensing With A Carbon Nanotube-Encapsulated Metal Chalcogenide Nanostructure, Harish Singh, Jiandong Wu, Kurt A.L. Lagemann, Manashi Nath Mar 2024

Highly Efficient Dopamine Sensing With A Carbon Nanotube-Encapsulated Metal Chalcogenide Nanostructure, Harish Singh, Jiandong Wu, Kurt A.L. Lagemann, Manashi Nath

Chemical and Biochemical Engineering Faculty Research & Creative Works

Carbon nanotube-encapsulated nickel selenide composite nanostructures were used as nonenzymatic electrochemical sensors for dopamine detection. These composite nanostructures were synthesized through a simple, one-step, and environmentally friendly chemical vapor deposition method, wherein the CNTs were formed in situ from pyrolysis of a carbon-rich metallo-organic precursor. The composition and morphology of these hybrid NiSe2-filled carbon nanostructures were confirmed by powder X-ray diffraction, Raman, X-ray photoelectron spectroscopy, and high-resolution transmission electron microscopy images. Electrochemical tests demonstrated that the as-synthesized hybrid nanostructures exhibited outstanding electrocatalytic performance toward dopamine oxidation, with a high sensitivity of 19.62 μA μM-1 cm-2, low detection limit, broad linear …

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Challenges And Opportunities In Electrification Of Adsorptive Separation Processes, Abdullah Al Moinee, Ali A. Rownaghi, Fateme Rezaei Mar 2024

Challenges And Opportunities In Electrification Of Adsorptive Separation Processes, Abdullah Al Moinee, Ali A. Rownaghi, Fateme Rezaei

Chemical and Biochemical Engineering Faculty Research & Creative Works

A global energy transition from fossil-based to renewable-based systems requires advancements in various energy sectors. Current chemical separation processes are quite energy-intensive and require significant advancement to make this transition happen. In the energy transition era, reducing the dependency of separation processes on fossil-based thermal energy seems inevitable for transitioning smoothly and meeting the stringent timelines. In particular, adsorption-based separation processes have the potential to be fully electrified through innovative strategies in developing stimuli-responsive adsorbents and swing processes. In this review, we discuss the recent efforts in electrification of adsorption processes and provide an overview of emerging materials and processes. …

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A Phenomenological Thermodynamic Energy Density Function For Ferroelectric Wurtzite Al1−Xscxn Single Crystals, Yijia Gu, Andrew C. Meng, Aiden Ross, Long Qing Chen Mar 2024

A Phenomenological Thermodynamic Energy Density Function For Ferroelectric Wurtzite Al1−Xscxn Single Crystals, Yijia Gu, Andrew C. Meng, Aiden Ross, Long Qing Chen

Materials Science and Engineering Faculty Research & Creative Works

A Landau-Devonshire thermodynamic energy density function for ferroelectric wurtzite aluminum scandium nitride (Al1−xScxN) solid solution is developed. It is parametrized using available experimental and theoretical data, enabling the accurate reproduction of composition-dependent ferroelectric properties, such as spontaneous polarization, dielectric permittivity, and piezoelectric constants, for both bulk and thin films. The maximum concentration of Sc for the wurtzite structure to remain ferroelectric is found to be 61 at. %. A detailed analysis of Al1−xScxN thin films reveals that the ferroelectric phase transition and properties are insensitive to substrate strain. This study lays the foundation for quantitative modeling of novel ferroelectric wurtzite …

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Characterizing Chemistry And Microbiomes During Continuous Anaerobic Codigestion Of Organics And Cattle Manure Digestate, Emily V. Schmitz, Hunter W. Schroer, Timothy E. Mattes, Craig L. Just Mar 2024

Characterizing Chemistry And Microbiomes During Continuous Anaerobic Codigestion Of Organics And Cattle Manure Digestate, Emily V. Schmitz, Hunter W. Schroer, Timothy E. Mattes, Craig L. Just

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

We characterized chemical and microbial responses to changes in the carbon-to-nitrogen ratio (C:N) and organic loading rate (OLR) during anaerobic codigestion (ACoD) of cattle manure digestate mixed with industrial organics. C:Ns of 25 and 35, both operating at OLRs ≤ 4 gVS L-1 d-1, sustained methane production averages of 0.36 ± 0.03 L gVS-1 d-1 and 0.32 ± 0.05 L gVS-1 d-1, respectively, throughout a 15-day period. Using 16S rRNA high-throughput sequencing coupled with PICRUSt2, taxonomy and predicted gene abundances were mapped to the major ACoD stages. C:N (25, 35) and the OLR (2, 4 gVS L-1 d-1) had minimal …

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Farmer Perceptions Of Land Cover Classification Of Uas Imagery Of Coffee Agroecosystems In Puerto Rico, Jose Cabrera, Blake Neal, Kevin Adkins, Ronny Schroeder, Gwendolyn Klenke, Shannon Brines, Nayethzi Hernandez, Kevin Li, Riley Glancy, Ivette Perfecto Mar 2024

Farmer Perceptions Of Land Cover Classification Of Uas Imagery Of Coffee Agroecosystems In Puerto Rico, Jose Cabrera, Blake Neal, Kevin Adkins, Ronny Schroeder, Gwendolyn Klenke, Shannon Brines, Nayethzi Hernandez, Kevin Li, Riley Glancy, Ivette Perfecto

Publications

Highly diverse agroecosystems are increasingly of interest as the realization of farms’ invaluable ecosystem services grows. Simultaneously there has been an increased use of uncrewed aerial systems (UAS) in remote sensing as drones offer a finer spatial resolution and faster revisit rate than traditional satellites. With the combined utility of UAS and the attention on agroecosystems, there exists an opportunity to assess UAS practicality in highly biodiverse settings. In this study, we utilized UAS to collect fine-resolution 10-band multispectral imagery of coffee agroecosystems in Puerto Rico. We created land cover maps through a pixel-based supervised classification of each farm and …

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Hybrid Deloading Control Strategy In Mmc-Based Wind Energy Conversion Systems For Enhanced Frequency Regulation, Jimiao Zhang, Jie Li Mar 2024

Hybrid Deloading Control Strategy In Mmc-Based Wind Energy Conversion Systems For Enhanced Frequency Regulation, Jimiao Zhang, Jie Li

Henry M. Rowan College of Engineering Departmental Research

The growing integration of renewable energy sources, especially offshore wind (OSW), is introducing frequency stability challenges to electric power grids. This paper presents a novel hybrid deloading control strategy that enables modular multilevel converter (MMC)-based wind energy conversion systems (WECSs) to actively contribute to grid frequency regulation. This research investigates a permanent-magnet synchronous generator (PMSG)-based direct-drive configuration, sourced from the International Energy Agency’s (IEA’s) 15 MW reference turbine model. Specifically, phase-locked loop (PLL)-free grid-forming (GFM) control is employed via the grid-side converter (GSC), and DC-link voltage control is realized through the machine-side converter (MSC), both of which boost the energy …

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Impact Of Welding Parameters In The Porosity Of A Dissimilar Welded Lap Joint Of Cp800-Xpf1000 Steel Weldment By Gmaw-P, Julio Cesar Garcia-Guerrero, Francisco Fernando Curiel-López, Víctor Hugo López-Morelos, Jaime Taha-Tijerina, Teresita Jesus Sánchez-Cruz, Maria Del Carmen Ramirez-Lopez, Eduardo Cortes-Carillo, Miguel Angel Quinones-Salinas Mar 2024

Impact Of Welding Parameters In The Porosity Of A Dissimilar Welded Lap Joint Of Cp800-Xpf1000 Steel Weldment By Gmaw-P, Julio Cesar Garcia-Guerrero, Francisco Fernando Curiel-López, Víctor Hugo López-Morelos, Jaime Taha-Tijerina, Teresita Jesus Sánchez-Cruz, Maria Del Carmen Ramirez-Lopez, Eduardo Cortes-Carillo, Miguel Angel Quinones-Salinas

Informatics and Engineering Systems Faculty Publications

The use of the orthogonal array L4 allows a determination of the effect between the welding parameters peak current (Ip), background current (Ib) and frequency (f) on the porosities in a dissimilar welded lap joint of CP800 and XPF1000 steel weldment by the gas metal arc welding process with the transfer pulsed mode. According to the results, modifications in the welding parameters affect the heat input during welding. A heat input higher than 0.30 KJ/mm generates up to 0.32% porosity in the weld metal, while a heat input lower than 0.25 KJ/mm generates up to 28% porosity in the weld …

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Composting Reduces The Risks Of Resistome In Beef Cattle Manure At The Transcriptional Level, Yuepeng Sun, Zachery R. Staley, Bryan Woodbury, Jean-Jack Riethoven, Xu Li Mar 2024

Composting Reduces The Risks Of Resistome In Beef Cattle Manure At The Transcriptional Level, Yuepeng Sun, Zachery R. Staley, Bryan Woodbury, Jean-Jack Riethoven, Xu Li

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Transcriptomic evidence is needed to determine whether composting is more effective than conventional stockpiling in mitigating the risk of resistome in livestock manure. The objective of this study is to compare composting and stockpiling for their effectiveness in reducing the risk of antibiotic resistance in beef cattle manure. Samples collected from the center and the surface of full-size manure stockpiling and composting piles were subject to metagenomic and metatranscriptomic analyses. While the distinctions in resistome between stockpiled and composted manure were not evident at the DNA level, the advantages of composting over stockpiling were evident at the transcriptomic level in …

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Graph Theory And Graph Neural Network Assisted High-Throughput Crystal Structure Prediction And Screening For Energy Conversion And Storage, Joshua Ojih, Mohammed Al-Fahdi, Yagang Yao, Jianjun Hu, Ming Hu Mar 2024

Graph Theory And Graph Neural Network Assisted High-Throughput Crystal Structure Prediction And Screening For Energy Conversion And Storage, Joshua Ojih, Mohammed Al-Fahdi, Yagang Yao, Jianjun Hu, Ming Hu

Faculty Publications

Prediction of crystal structures with desirable material properties is a grand challenge in materials research, due to the enormous search space of possible combinations of elements and their countless arrangements in 3D space. Despite the recent progress of a few crystal structure prediction algorithms, most of those methods only target a few specific material families or are restricted to simple systems with limited element diversity. Moreover, these algorithms are usually coupled with first principles calculations and thus are computationally expensive and very time consuming. Therefore, establishing a workflow that can generate a large number of hypothetical structures with diverse elements …

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Laboratory Exercise For The Radiometry Student, Michael A. Marciniak Mar 2024

Laboratory Exercise For The Radiometry Student, Michael A. Marciniak

Faculty Publications

The U.S. Air and Space Forces require optical expertise among their personnel. The Air Force Institute of Technology offers a graduate optics curriculum, which includes a three-course sequence to educate students in the optical concepts of radiometry and radiometric instrumentation. We find radiometry is often a deceptively difficult concept for students to master. To address this, we have developed an experiment in our optics-laboratory coursework to help them gain this mastery. A Fourier-transform infrared spectrometer (FTS) is used to collect spectral data from an unknown sample. FTS calibration and data collection are discussed here, as are the two specific samples …

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