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Articles 2371 - 2400 of 21777

Full-Text Articles in Engineering

Updates And Improvements To The Satellite Drag Coefficient Response Surface Modeling Toolkit, Phillip Logan Sheridan, Smriti Nandan Paul, Guillermo Avendaño-Franco, Piyush M. Mehta May 2022

Updates And Improvements To The Satellite Drag Coefficient Response Surface Modeling Toolkit, Phillip Logan Sheridan, Smriti Nandan Paul, Guillermo Avendaño-Franco, Piyush M. Mehta

Mechanical and Aerospace Engineering Faculty Research & Creative Works

For satellites in the Low Earth Orbit (LEO) region, the drag coefficient is a primary source of uncertainty for orbit determination and prediction. Researchers at the Los Alamos National Laboratory (LANL) have created the so-called Response Surface Modeling (RSM) toolkit to provide the community with a resource for simulating and modeling satellite drag coefficients for satellites with complex geometries (modeled using triangulated facets) in the free molecular flow (FMF) regime. The toolkit fits an interpolation surface using non-parametric Gaussian Process Regression (GPR) over drag coefficient data computed using the numerical Test Particle Monte Carlo (TPMC) method. The fitted response surface …


Relating Detonation Parameters To The Detonation Synthesis Of Silicon Carbide, Martin Langenderfer, Eric W. Bohannan, Jeremy Lee Watts, William Fahrenholtz, Catherine E. Johnson May 2022

Relating Detonation Parameters To The Detonation Synthesis Of Silicon Carbide, Martin Langenderfer, Eric W. Bohannan, Jeremy Lee Watts, William Fahrenholtz, Catherine E. Johnson

Chemistry Faculty Research & Creative Works

Detonation synthesis of silicon carbide (SiC) nanoparticles from carbon liberated by negatively oxygen balanced explosives was evaluated in a 23 factorial design to determine the effects of three categorical experimental factors: (1) cyclotrimethylene-trinitramine (RDX)/2,4,6-trinitrotoluene (TNT) ratio, (2) silicon (Si) additive concentration, and (3) Si particle size. These factors were evaluated at low and high levels as they relate to the detonation performance of the explosive and the solid Si-containing phases produced. Detonation velocity and Chapman-Jouguet (C-J) detonation pressure, which were measured using rate stick plate dent tests, were evaluated. Solid detonation product mass, silicon carbide product concentration, and residual silicon …


Globule Masks-Exact.Zip, Ananad K. Nambisan, Norsang Lama, Jason Hagerty, Colin Smith, Ahmad Rajeh, Thanh Phan, Samantha Swinfard, R. Joe Stanley May 2022

Globule Masks-Exact.Zip, Ananad K. Nambisan, Norsang Lama, Jason Hagerty, Colin Smith, Ahmad Rajeh, Thanh Phan, Samantha Swinfard, R. Joe Stanley

Deep Learning-based Dot and Globule Segmentation with Pixel and Blob-based Metrics for Evaluation – Data

No abstract provided.


Structural Design For Fire Conditions Of A Prototype Metal Building Using The New Proposed Appendix To Aisi S100, Xia Yan, Thomas Gernay May 2022

Structural Design For Fire Conditions Of A Prototype Metal Building Using The New Proposed Appendix To Aisi S100, Xia Yan, Thomas Gernay

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

Performance-based design for fire conditions has been increasingly adopted for different structural systems over the last decade. The objective of this project is to exemplify through a case study how the newly proposed Appendix 4 to AISI S100 [1] on ‘Structural Design for Fire Conditions’ could be used by the metal building industry. The scope of work on the project includes the following:

(1) Identification of a prototype metal building to serve as an exemplar case study for the structural fire design procedure.

(2) Definition of the performance objectives and design requirements for the building in the fire situation. This …


Globule Masks-Dilatedellipsekernel3.Zip, Ananad K. Nambisan, Norsang Lama, Jason Hagerty, Colin Smith, Ahmad Rajeh, Thanh Phan, Samantha Swinfard, R. Joe Stanley May 2022

Globule Masks-Dilatedellipsekernel3.Zip, Ananad K. Nambisan, Norsang Lama, Jason Hagerty, Colin Smith, Ahmad Rajeh, Thanh Phan, Samantha Swinfard, R. Joe Stanley

Deep Learning-based Dot and Globule Segmentation with Pixel and Blob-based Metrics for Evaluation – Data

No abstract provided.


Images.Zip, Ananad K. Nambisan, Norsang Lama, Jason Hagerty, Colin Smith, Ahmad Rajeh, Thanh Phan, Samantha Swinfard, R. Joe Stanley May 2022

Images.Zip, Ananad K. Nambisan, Norsang Lama, Jason Hagerty, Colin Smith, Ahmad Rajeh, Thanh Phan, Samantha Swinfard, R. Joe Stanley

Deep Learning-based Dot and Globule Segmentation with Pixel and Blob-based Metrics for Evaluation – Data

No abstract provided.


Understanding The Role Of Nano-Tio2 On The Toxicity Of Pb On C. Dubia Through Modeling—Is It Additive Or Synergistic?, Xuesong Liu, Jianmin Wang, Yue-Wern Huang May 2022

Understanding The Role Of Nano-Tio2 On The Toxicity Of Pb On C. Dubia Through Modeling—Is It Additive Or Synergistic?, Xuesong Liu, Jianmin Wang, Yue-Wern Huang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Nano-TiO2 can remarkably increase lead (Pb) toxicity in aquatic organisms. However, the mechanism of this toxicity, additive or synergistic, is not well understood. To explore this mechanism, we inspected the role of nano-TiO2 in the toxicity of Pb on Ceriodaphnia dubia (C. dubia), a model water flea species typically used for ecotoxicity studies. The effect of algae, a diet for aquatic organisms, on the effect of this binary mixture was also investigated. A two-compartment toxicokinetic (TK)-toxicodynamic (TD) modeling approach was used to quantify the Pb toxicity under these complex conditions and to develop critical parameters for understanding the …


A New Look At Landslides Of The Vermilion And Echo Cliffs, Northern Arizona, Conor M. Watkins, J. David Rogers May 2022

A New Look At Landslides Of The Vermilion And Echo Cliffs, Northern Arizona, Conor M. Watkins, J. David Rogers

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The Vermilion and Echo Cliffs form a nearly continuous escarpment more than 160 km long within the Colorado Plateau physiographic province of North America. The cliffs overlie the Marble Platform in northern Arizona and are located along the Colorado River, just upstream of the Grand Canyon. Large rotational block landslides mantle the erosional escarpment along most of its extent. Although these landslides have been noted for over 100 years, their likely origin has never been explained. Landslide failure surfaces appear to be influenced by the Petrified Forest Member of the Triassic Chinle Formation, a shale layer containing smectite clay weathered …


Light Emission Of Self-Trapped Excitons From Ion Tracks In Silica Glass: Interplay Between Auger Recombination, Exciton Formation, Thermal Dissociation, And Hopping, Joseph T. Graham, Miguel L. Crespillo, Fernando Agulló-López, William J. Weber May 2022

Light Emission Of Self-Trapped Excitons From Ion Tracks In Silica Glass: Interplay Between Auger Recombination, Exciton Formation, Thermal Dissociation, And Hopping, Joseph T. Graham, Miguel L. Crespillo, Fernando Agulló-López, William J. Weber

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

The initial luminescence yield of amorphous silica under ion irradiation has been studied at temperatures between 30 and 100 K, using swift ions of different masses and energies (3 MeV H, 3.5 MeV He, 19 MeV Si and 19 MeV Cl). The intensity of the 2.1 eV emission band, ascribed to the intrinsic recombination of self-trapped excitons (STEs), has been found to vary systematically with ion mass, energy and irradiation temperature. A detailed model has been developed to quantitatively describe those variations in terms of the competition between non-radiative Auger recombination, STE formation, STE thermal dissociation, and subsequent STE hopping …


The Bridge Newsletter Spring 2022, Missouri University Of Science And Technology May 2022

The Bridge Newsletter Spring 2022, Missouri University Of Science And Technology

The Bridge Newsletter

-CArEE faculty awarded Kummer Ignition Grants
-Geldert-Murphey poised to become ASCE’s 2023 president-elect
-Nine new members inducted during Academy of Civil Engineers 50th anniversary celebration
-Steel Bridge Team wins fourth consecutive regional competition, will compete at nationals


For The Improvement Of Mechanical And Microstructural Properties Of Uhpc With Fiber Alignment Using Carbon Nanotube And Graphite Nanoplatelet, Huanghuang Huang, Le Teng, Kamal Khayat, Xiaojian Gao, Fazhou Wang, Zhichao Liu May 2022

For The Improvement Of Mechanical And Microstructural Properties Of Uhpc With Fiber Alignment Using Carbon Nanotube And Graphite Nanoplatelet, Huanghuang Huang, Le Teng, Kamal Khayat, Xiaojian Gao, Fazhou Wang, Zhichao Liu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper investigates the influence of carbon nanotube (CNT) and graphite nanoplatelet (GNP) on the microstructure and mechanical characteristics of UHPC with steel fiber alignment. The content of CNT and GNP ranged from 0 to 0.3%, by mass of binder. Predominant fiber alignment was manipulated using a flow-induced casting method during UHPC placement. Experiment results indicated that the increase of CNT and GNP content from 0 to 0.3% led to 15%, 40%, and 50% improvement in compressive strength, flexural strength, and T150 (dissipated energy) of UHPC, respectively. Fiber alignment was shown to increase flexural strength and T150 by 30% and …


Administering Change Orders In Highway Projects, Muaz O. Ahmed, Rayan H. Assaad, Islam H. El-Adaway, Emily Echele, Kyle Govro, John Watson May 2022

Administering Change Orders In Highway Projects, Muaz O. Ahmed, Rayan H. Assaad, Islam H. El-Adaway, Emily Echele, Kyle Govro, John Watson

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Change orders continue to be one of the main challenges faced by the construction industry. Despite many previous research efforts related to managing change orders in the construction industry, there is still a lack of research that investigates the contractual aspects of change orders for transportation projects. This paper tackles this knowledge gap within the context of Ohio Department of Transportation (ODOT) highway projects. To this end, the authors used an integrated research method comprised of (1) selection and analysis of ODOT case studies; (2) identification of the main change orders aspects that lead to conflicts, claims, and/or disputes in …


Exploring The Deformation Mechanics Of Coal Ribs Using The Distinct Element Modeling Approach, Maurice Sunkpal, Taghi Sherizadeh May 2022

Exploring The Deformation Mechanics Of Coal Ribs Using The Distinct Element Modeling Approach, Maurice Sunkpal, Taghi Sherizadeh

Mining Engineering Faculty Research & Creative Works

Understanding coal rib geomechanics is essential for improving rib stability and eliminating fatality and injury trends due to rib failures. There are presently no standardized rib control practices available in most countries. In light of this observed dearth, this investigation aims to improve understanding of rib failure mechanisms using the distinct element modeling (DEM) technique. DEM is chosen because of its superior advantage to explicitly represent discontinuities and their constitutive behaviors, besides that of the intact rock matrix. To analyze the rib stability, a numerical monitoring protocol is implemented to monitor the deformation characteristics of the coal rock mass as …


Evolution Prediction Of Hysteresis Behavior Of Sand Under Cyclic Loading, Pingxin Xia, Longtan Shao, Wen Deng, Chao Zeng May 2022

Evolution Prediction Of Hysteresis Behavior Of Sand Under Cyclic Loading, Pingxin Xia, Longtan Shao, Wen Deng, Chao Zeng

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Soil cyclic degradation is a serious issue that should be considered in engineering design and maintenance. The hysteretic response causes strength degradation and excessive settlement of soil structure in engineered and natural geosystems. Hysteresis is essentially the coupling deformation of elastic and plastic components during reloading and unloading processes. Conventional hysteretic models for sand in the elastoplastic framework rely highly on yield surface or potential surface evolution and fall short on complexity and inaccuracy. This study proposes a decoupling method to describe the hysteretic response of sand. In contrast to the conventional elastoplastic approach, this decoupling method can directly decouple …


Implementation Of The Linear Amplitude Sweep Test To Evaluate Fatigue Resistance Of Highly Polymerized Asphalt Binders, Jun Liu, Yizhuang David Wang, Jenny Liu May 2022

Implementation Of The Linear Amplitude Sweep Test To Evaluate Fatigue Resistance Of Highly Polymerized Asphalt Binders, Jun Liu, Yizhuang David Wang, Jenny Liu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Highly polymerized asphalt binders (HPABs) such as PG 64-40 have been increasingly used in cold regions such as Alaska in recent years. However, there are currently considerable data gaps when it comes to the characterizations of the HPABs, especially their fatigue behaviors. The objective of this study is to apply the linear amplitude sweep (LAS) test with the viscoelastic continuum damage (VECD) model to assess the fatigue resistance of HPABs. Three HPABs (PG 52-40, PG 64-40, and PG 52-46) and one unmodified binder (PG 52-28) were used in the study. The fatigue failure during LAS tests on HPABs was defined, …


Comprehensive Evaluation Of Self-Healing Polyampholyte Gel Particles For The Severe Leakoff Control Of Drilling Fluids, Lili Yang, Chunlin Xie, Tian Ao, Kaixiao Cui, Guancheng Jiang, Baojun Bai, Yongwei Zhang, Jun Yang, Xingxing Wang, Weiguo Tian May 2022

Comprehensive Evaluation Of Self-Healing Polyampholyte Gel Particles For The Severe Leakoff Control Of Drilling Fluids, Lili Yang, Chunlin Xie, Tian Ao, Kaixiao Cui, Guancheng Jiang, Baojun Bai, Yongwei Zhang, Jun Yang, Xingxing Wang, Weiguo Tian

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Lost circulation has been a serious problem to be solved in many drilling practices during oil, gas and geothermal well drillings. Many materials have been developed and evaluated for the purpose. However, their performance to plug severe leakoff is very limited. Herein, an injectable self-healing hydrogel based on polyampholyte with sulfonated and quaternary ammonium functionalities (P(MPTC-co-NaSS)) was developed and comprehensively evaluated to prevent the severe loss of fluids to formation. By incorporating cation-π (π is for aromatic residues) interaction, the hydrogel shown self-healing property and robustness in severe environment (temperature, salt) by comparison with other hydrogels merely consisting of cation-anion …


Design Of Wideband Decoupling Networks For Mimo Antennas Based On An N-Ary Optimization Algorithm, Min Li, Kwan Lawrence Yeung, Lijun Jiang, Ross Murch May 2022

Design Of Wideband Decoupling Networks For Mimo Antennas Based On An N-Ary Optimization Algorithm, Min Li, Kwan Lawrence Yeung, Lijun Jiang, Ross Murch

Electrical and Computer Engineering Faculty Research & Creative Works

Techniques for reducing the coupling between antenna elements in multiple-input multiple-output (MIMO) systems are important for achieving the full potential of MIMO. In this article, a general and systematic method is developed to design a wideband decoupling and matching network (DMN) for MIMO antenna arrays. The DMN is formed by grid-like transmission lines interconnected by lumped components, whose reactance can be obtained from an N-ary optimization algorithm. Four design benchmarks are performed for validating decoupling methodology, elaborating on design/implementation procedure, and demonstrating superiority of the proposed method. Results show that the DMN achieves broad isolation bandwidth while occupying a small …


A New Rock Hardness Classification System Based On Portable Dynamic Testing, Sasan Ghorbani, Seyed Hadi Hoseinie, Ebrahim Ghasemi, Taghi Sherizadeh, Christina Wanhainen May 2022

A New Rock Hardness Classification System Based On Portable Dynamic Testing, Sasan Ghorbani, Seyed Hadi Hoseinie, Ebrahim Ghasemi, Taghi Sherizadeh, Christina Wanhainen

Mining Engineering Faculty Research & Creative Works

Hardness is one of the critical physical characteristics of minerals and rocks, which indicates the resistance of the rock to penetration, scratch, or permanent deformation. As a basic concept, rock hardness has a significant role in rock mechanics and geological engineering and is an appropriate diagnostic tool for the classification of minerals and rocks. The main purpose of this study is to guide rock engineers to measure the rock hardness faster, easier, and more accurately using Leeb's dynamic hardness test. Accordingly, this paper presents a new rock hardness classification system based on the Leeb dynamic and portable hardness testing method. …


Preparation Of Concrete Specimen For Internal Sulfate Attack Analysis Using Electron Backscatter Diffraction, R. Sharon Uwanyuze, Lucas Enright, Jiyao Zhang, Stefan Schafföner May 2022

Preparation Of Concrete Specimen For Internal Sulfate Attack Analysis Using Electron Backscatter Diffraction, R. Sharon Uwanyuze, Lucas Enright, Jiyao Zhang, Stefan Schafföner

Materials Science and Engineering Faculty Research & Creative Works

Concrete cores were obtained from houses in eastern Connecticut, USA, that had varying degrees of crumbling foundations and wall cracking. Electron backscatter diffraction (EBSD) was used simultaneously with energy dispersive X-ray spectroscopy to investigate the degradation of these samples. This combination allowed the precise correlation of elemental composition with mineral crystallography phase mapping. EBSD examination showed the presence of pyrrhotite, pyrite, and marcasite phases in some of the samples, whereas internal sulfate attack (ISA) is triggered by the release of sulfates through the oxidation of such iron sulfides. Secondary expansion products from ISA are associated with foundation cracking, wall bulging, …


Study Of Gas Holdup Distribution In Cylindrical Split Airlift Reactor By Using Gamma-Ray Densitometry (Grd), Abbas J. Sultan, Laith S. Sabri, Hasan Shakir Majdi, Shadha K. Jebur, Muthanna H. Al-Dahhan May 2022

Study Of Gas Holdup Distribution In Cylindrical Split Airlift Reactor By Using Gamma-Ray Densitometry (Grd), Abbas J. Sultan, Laith S. Sabri, Hasan Shakir Majdi, Shadha K. Jebur, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

The local gas holdup details and behaviors in the cylindrical split airlift column by using an unconventional gamma-ray densitometry (GRD) measurement in non-invasive manner technique was investigated for the first time in this work for such kind of airlift column. With different gas velocities, 1, 2, and 3 cm/s, at three various axial planes (different levels) in z = 3, 60, and 110 cm were studied for local distribution in radial gas holdup profiles. The distribution in gas–liquid phases (air-water system) in the entire split reactor column, in the rising and descending sides, including their behavior in the upper and …


Process Evaluation And Kinetic Analysis Of 3d-Printed Monoliths Comprised Of Cao And Cr/H-Zsm-5 In Combined Co2 Capture-C2h6 Oxidative Dehydrogenation To C2h4, Khaled Baamran, Shane Lawson, Ali A. Rownaghi, Fateme Rezaei May 2022

Process Evaluation And Kinetic Analysis Of 3d-Printed Monoliths Comprised Of Cao And Cr/H-Zsm-5 In Combined Co2 Capture-C2h6 Oxidative Dehydrogenation To C2h4, Khaled Baamran, Shane Lawson, Ali A. Rownaghi, Fateme Rezaei

Chemical and Biochemical Engineering Faculty Research & Creative Works

In this study, dual-function materials (DFMs) comprised of CaO and Cr/H-ZSM-5 were formulated in 3D-printed monolithic structures and investigated in a combined process for capture and utilization of CO2 in oxidative dehydrogenation of C2H6 to C2H4 (CO2-ODHE). Various formulation strategies were employed to fabricate these DFM structures. Two bed designs were considered: i) a layered-bed in which adsorbent (CaO) and catalyst were printed separately and stacked on top of each other, and ii) a single-layer bed where the adsorbent-catalyst materials were 3D-printed into a singular monolith and loaded into the bed …


Integration Of Dynamic Growth Modeling And Hydrodynamics In An Internal-Loop Split Photobioreactor, Laith S. Sabri, Aastha Ojha, Abbas J. Sultan, Muthanna H. Aldahhan May 2022

Integration Of Dynamic Growth Modeling And Hydrodynamics In An Internal-Loop Split Photobioreactor, Laith S. Sabri, Aastha Ojha, Abbas J. Sultan, Muthanna H. Aldahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

In this study, new high-quality experimental data for culturing green microalgae Scenedesmus in tubular and cylindrical split airlift photobioreactors were obtained under different operating conditions. The obtained experimental data of culturing microalgae Scenedesmus in a tubular photobioreactor were used for determining the kinetic parameters of the photosynthetic reaction. On the other hand, the culturing of green microalgae in a split airlift photobioreactor was used to measure the microalgae cell trajectory using an advanced radioactive particle tracking (RPT) technique. The obtained results in terms of kinetic parameters of the photosynthetic reaction and microalgae cell trajectory were integrated for the first time …


Random Trilobe Packing Using Rigid Body Approach And Local Gas-Liquid Hydrodynamics Simulation Through Cfd With Experimental Validation, Binbin Qi, Sebastián Uribe, Omar Farid, Muthanna H. Al-Dahhan May 2022

Random Trilobe Packing Using Rigid Body Approach And Local Gas-Liquid Hydrodynamics Simulation Through Cfd With Experimental Validation, Binbin Qi, Sebastián Uribe, Omar Farid, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

It is quite difficult to measure the local information of the gas/liquid flow inside random packed extrudate catalyst beds in a large scale. Obtaining the local information through computational fluid dynamic (CFD) simulations in such system is also difficult due to the complexity of random particle packing and two-phase flow simulation. An efficient packing scheme was implemented to randomly pack 2917 trilobe particles (10 cm in height) in a 2-inch column to represent the trickle bed reactor (TBR) based on the rigid body approach. The generated geometry was used to define the computational domain for the two-phase hydrodynamics simulation based …


Hydration Of High-Alumina Calcium Aluminate Cements With Carbonate And Sulfate Additives, Jonathan Lapeyre, Sai Akshay Ponduru, Monday Uchenna Okoronkwo, Hongyan Ma, Aditya Kumar May 2022

Hydration Of High-Alumina Calcium Aluminate Cements With Carbonate And Sulfate Additives, Jonathan Lapeyre, Sai Akshay Ponduru, Monday Uchenna Okoronkwo, Hongyan Ma, Aditya Kumar

Chemical and Biochemical Engineering Faculty Research & Creative Works

This study investigated the influence of limestone (LS) and calcium sulfate (C$) mineral additives on the hydration kinetics of high-α-Al2O3 calcium aluminate cement (CAC) utilizing experimental techniques and thermodynamic simulations. Increasing the replacement level of limestone or calcium sulfate increased the cumulative heat of the hydration reaction. The limestone exhibited limited acceleratory effects to the CAC hydration kinetics due to the coarseness of the powder. The coarse particle size distribution limited any heterogenous nucleation that would have occurred with a finer particle size as well as the intrinsic insolubility kinetically limits the formation of monocarboaluminate phases. Conversely, …


Liquid And Solids Phase Backmixing In A Bubble And Slurry Bubble Column Using A Virtual Tracer Response Methodology Based On The Trajectory Data Of The Radioactive Particle Tracking (Rpt) Technique, Lu Han, Premkumar Kamalanathan, Muthanna H. Al-Dahhan May 2022

Liquid And Solids Phase Backmixing In A Bubble And Slurry Bubble Column Using A Virtual Tracer Response Methodology Based On The Trajectory Data Of The Radioactive Particle Tracking (Rpt) Technique, Lu Han, Premkumar Kamalanathan, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

Virtual tracer response methodology developed based on the trajectory data of the computer aided radioactive particle tracking (CARPT) technique was demonstrated. The demonstrated virtual tracer technique has advantages of non-invasiveness, near perfect injection/sampling, and flexibility in choosing the sampling/injection boundaries in a specific spatial pattern. With the developed virtual tracer technique, liquid and solids back mixing was investigated at the conditions mimicking Fischer-Tropsch synthesis. Experiments were conducted at different pressure, solids loading, and superficial gas velocity. The axial dispersion model (ADM) and recirculation and cross flow dispersion (RCFD) models were used to model the liquid mixing. Transient sedimentation dispersion model …


Review Of Biomechanical Studies And Finite Element Modeling Of Sternal Closure Using Bio-Active Adhesives, Amatulraheem Al-Abassi, Marcello Papini, Mark R. Towler May 2022

Review Of Biomechanical Studies And Finite Element Modeling Of Sternal Closure Using Bio-Active Adhesives, Amatulraheem Al-Abassi, Marcello Papini, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

The most common complication of median sternotomy surgery is sternum re-separation after sternal fixation, which leads to high rates of morbidity and mortality. The adhered sternal fixation technique comprises the wiring fixation technique and the use of bio-adhesives. Adhered sternal fixation techniques have not been extensively studied using finite element analysis, so mechanical testing studies and finite element analysis of sternal fixation will be presented in this review to find the optimum techniques for simulating sternal fixation with adhesives. The optimal wiring technique should enhance bone stability and limit sternal displacement. Bio-adhesives have been proposed to support sternal fixation, as …


Solid-State Formation Mechanisms Of Core–Shell Microstructures In (Zr,Ta)B2 Ceramics, Anna N. Dorner, Frédéric Monteverde, William Fahrenholtz, Gregory E. Hilmas May 2022

Solid-State Formation Mechanisms Of Core–Shell Microstructures In (Zr,Ta)B2 Ceramics, Anna N. Dorner, Frédéric Monteverde, William Fahrenholtz, Gregory E. Hilmas

Materials Science and Engineering Faculty Research & Creative Works

Transition metal diborides with core–shell microstructures have demonstrated excellent mechanical properties at elevated temperatures. Previous studies concluded that core–shell microstructures were formed by liquid-assisted mass transport mechanisms, but in this study, we propose a solid-state formation mechanism for core-shell microstructures in (Zr,Ta)B2 ceramics produced by reaction hot pressing and in ZrB2-TaB2 diffusion couples. Diffusion couple experiments demonstrated that core–shell microstructures developed as a result of Ta diffusion along ZrB2 grain boundaries, which occurred concurrently with lattice diffusion of Ta into ZrB2. These findings suggest that with optimization of batching and processing parameters, core–shell diboride materials may be formed through solid-state …


Use Of Saturated Lightweight Sand To Improve The Mechanical And Microstructural Properties Of Uhpc With Fiber Alignment, Huanghuang Huang, Le Teng, Xiaojian Gao, Kamal Khayat, Fazhou Wang, Zhichao Liu May 2022

Use Of Saturated Lightweight Sand To Improve The Mechanical And Microstructural Properties Of Uhpc With Fiber Alignment, Huanghuang Huang, Le Teng, Xiaojian Gao, Kamal Khayat, Fazhou Wang, Zhichao Liu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper studied the influence of pre-saturated lightweight sand (LWS) on the mechanical and microstructural properties of UHPC cast with steel fiber alignment. The changes in hydration kinetics, porosity, nano-mechanical, and mechanical properties were studied. The LWS was used at 0–50% replacement volumes of total sand. Predominant fiber alignment was favored through a flow-induced casting method during casting of flexural prisms. Experiment results showed that the 28-d autogenous shrinkage was decreased from 450 to 275 μm/m with the LWS content increasing from 0 to 50%. The addition of 20% LWS led to maximum increases of 15%, 15%, and 20% in …


Establishing Pteridine Metabolism In A Progressive Isogenic Breast Cancer Cell Model – Part Ii, Lindsey Rasmussen, Zachary Foulks, Jiandong Wu, Casey Burton, Honglan Shi May 2022

Establishing Pteridine Metabolism In A Progressive Isogenic Breast Cancer Cell Model – Part Ii, Lindsey Rasmussen, Zachary Foulks, Jiandong Wu, Casey Burton, Honglan Shi

Chemistry Faculty Research & Creative Works

Introduction: Determining the biological significance of pteridines in cancer development and progression remains an important step in understanding the altered levels of urinary pteridines seen in certain cancers. Our companion study revealed that several folate-derived pteridines and lumazines correlated with tumorigenicity in an isogenic, progressive breast cancer cell model, providing direct evidence for the tumorigenic origin of pteridines. Objectives: This study sought to elucidate the pteridine biosynthetic pathway in a progressive breast cancer model via direct pteridine dosing to determine how pteridine metabolism changes with tumorigenicity. Methods: First, MCF10AT breast cancer cells were dosed individually with 15 pteridines to determine …


Quantitative Holistic Assessment Of Implementing Collaborative Planning Practices, Amr Elsayegh, Islam H. El-Adaway May 2022

Quantitative Holistic Assessment Of Implementing Collaborative Planning Practices, Amr Elsayegh, Islam H. El-Adaway

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Practices of collaborative planning - as related to novel project delivery methods, information technologies, lean construction, and supply chain practices - can impact the cost and schedule performance of projects in the architectural, engineering, and construction (AEC) industry. However, there is a lack of research providing a quantitative holistic assessment of implementing collaborative planning practices. This paper fills this knowledge gap. Using an interdependent multistep research methodology, the authors (1) analyzed a holistic literature-based list of collaborative planning risks using 46 responses from industry expert surveys; (2) calculated the criticality of these risks and compared the obtained results using Spearman …