Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Marquette University

Discipline
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 211 - 240 of 2083

Full-Text Articles in Engineering

Fixed-Bed Column Study Of Phosphate Adsorption Using Immobilized Phosphate-Binding Protein, Faten B. Hussein, Brooke K. Mayer May 2022

Fixed-Bed Column Study Of Phosphate Adsorption Using Immobilized Phosphate-Binding Protein, Faten B. Hussein, Brooke K. Mayer

Civil and Environmental Engineering Faculty Research and Publications

Bio-adsorption using high-affinity phosphate-binding proteins (PBP) has demonstrated effective phosphorus removal and recovery in batch-scale tests. Subsequent optimization of design and performance of fixed-bed column systems is essential for scaling up and implementation. Here, continuous-flow fixed-bed column tests were used to investigate the adsorption of inorganic phosphate (orthophosphate, Pi) using phosphate-binding proteins immobilized on resin (PBP–NHS) targeting Pi removal to ultra-low levels followed by recovery. Time to breakthrough decreased with higher influent Pi concentration, smaller bed volume, and higher influent flow rates. The Thomas and Yoon-Nelson breakthrough models adequately described PBP-NHS resin performance with a correlation coefficient of R2 > 0.95. …


Low-Latency And Fresh Content Provision In Information-Centric Vehicular Networks, Shan Zhang, Junjie Li, Hongbin Luo, Jie Gao, Lian Zhao, Xuemin Sherman Shen May 2022

Low-Latency And Fresh Content Provision In Information-Centric Vehicular Networks, Shan Zhang, Junjie Li, Hongbin Luo, Jie Gao, Lian Zhao, Xuemin Sherman Shen

Electrical and Computer Engineering Faculty Research and Publications

In this paper, the content service provision of information-centric vehicular networks (ICVNs) is investigated from the aspect of mobile edge caching, considering the dynamic driving-related context information. To provide up-to-date information with low latency, two schemes are designed for cache update and content delivery at the roadside units (RSUs). The roadside unit centric (RSUC) scheme decouples cache update and content delivery through bandwidth splitting, where the cached content items are updated regularly in a round-robin manner. The request adaptive (ReA) scheme updates the cached content items upon user requests with certain probabilities. The performance of both proposed schemes are analyzed, …


Nematic Liquid Crystal Carbon Nanotube Composite Materials For Designing Rf Switching Devices, Jeffrey Josse Apr 2022

Nematic Liquid Crystal Carbon Nanotube Composite Materials For Designing Rf Switching Devices, Jeffrey Josse

Master's Theses (2009 -)

Radio frequency microelectromechanical systems (RF MEMS) devices are microdevices used to switch or modify signals from the RF to millimeter wave (mmWave) frequency range. Liquid crystals (LCs) are widely used as electro-optic modulators for display devices. An electric field-induced electrical conductivity modulation of pure LC media is quite low which makes it difficult to use for RF MEMS switching applications. Currently, RF MEMS devices are characterized as an excellent option between solid-state and electromechanical RF switches to provide high isolation, low insertion loss, low power usage, excellent return loss, and large frequency band. However, commercial usage is low due to …


Fast-Pgmed: Fast And Dense Elevation Determination For Earthwork Using Drone And Deep Learning, Sisi Han, Yuhan Jiang, Yong Bai Apr 2022

Fast-Pgmed: Fast And Dense Elevation Determination For Earthwork Using Drone And Deep Learning, Sisi Han, Yuhan Jiang, Yong Bai

Civil and Environmental Engineering Faculty Research and Publications

This paper presents a time- and cost-effective elevation determination method for earthwork operations using ready-to-fly imaging drones and deep learning technologies. The proposed method is named the fast pixel grid/group matching and elevation determination (Fast-PGMED) algorithm. The input data are a pair of approximate 2:1-scale top-view images, and the output is the determined elevation map for the scanned station. Feature matching of the two multiscale images is conducted by calculating correlations between target patch predictions (via DeepMatchNet, a fully convolutional network) and potential target patches (via virtual elevation model). The overall processing time is about 21 s …


Activated Sludge Foaming Descriptors And Correlation To Microbial Community Composition, Grace K. Scarim Apr 2022

Activated Sludge Foaming Descriptors And Correlation To Microbial Community Composition, Grace K. Scarim

Master's Theses (2009 -)

Activated sludge is a conventional treatment process for biochemical oxygen demand (BOD) and total suspended solids (TSS) removal at water resource recovery facilities (WRRFs). A common operational issue that arises is activated sludge foaming on top of the aeration basin and secondary clarifier. Foaming events in activated sludge may lead to decreased treatment efficiency, maintenance issues, and potential environmental health risks. Stable foaming events are caused by biological and chemical drivers (i.e., microbes and surfactants) during the aeration process. However, foaming events are difficult to predict and quantify. This research developed an inexpensive and easy-to-use method to quantify foaming potential …


Uv Light Emitting Diodes (Led) For Degradation Of Antibiotic Resistant Bacteria And Genes, Nicole Anne Heyniger Apr 2022

Uv Light Emitting Diodes (Led) For Degradation Of Antibiotic Resistant Bacteria And Genes, Nicole Anne Heyniger

Master's Theses (2009 -)

The presence of antibiotic resistant bacteria (ARB) and antibiotic resistant genes (ARGs) in the environment is a growing issue, which been exacerbated by the overuse and misuse of antibiotics in various healthcare and agricultural systems. One possible means of antibiotic resistance mitigation is through drinking water and wastewater treatment, specifically disinfection processes. Ultraviolet light emitting diodes (UV-LEDs) are an emerging disinfection technology that utilize LEDs that emit at varying peak wavelengths in the UV light spectrum. This study analyzed the effect of UV-LED on ARB and ARGs compared to conventional low-pressure UV (LP-UV) treatment and calculated electrical energy efficiencies for …


Monitoring The Hydrologic And Water Quality Performance Of A Subsurface Gravel Wetland, Catherine Sullivan Apr 2022

Monitoring The Hydrologic And Water Quality Performance Of A Subsurface Gravel Wetland, Catherine Sullivan

Master's Theses (2009 -)

Managing stormwater is a crucial task for many communities that are required to mitigate the harmful effects of pollution from urban runoff. Subsurface gravel wetlands are an emerging type of green infrastructure that can be used to manage stormwater through the capture and slow release of runoff. These wetland systems are unique to other types of green infrastructure in that they have a distinct fully saturated gravel layer below an occasionally saturated soil layer. While there is substantial literature on the performance of different types of green infrastructure, such as bioretention, bioswales, and permeable pavements, there is a lack of …


Wet Detention Pond Phosphorus Cycling Dynamics: Evaluation Of Pond Performance And Application Of The General Lake Model, Caitlin Lulay Apr 2022

Wet Detention Pond Phosphorus Cycling Dynamics: Evaluation Of Pond Performance And Application Of The General Lake Model, Caitlin Lulay

Master's Theses (2009 -)

Anthropogenic activities degrade surface water quality by increasing nutrient input to the watershed which is transported via stormwater runoff and accumulated in waterbodies leading to eutrophication. Wet detention ponds are a means of mitigating the impacts of these non-point source pollutants, such as phosphorus (P), through treatment mechanisms such as sediment settling and biological uptake. While these wet detention ponds are designed to serve as P sinks, they have the potential to serve as P sources as well due to release mechanisms such as sediment resuspension and algal decay. Many existing models used in the design and performance evaluation of …


Numerical Studies Of A Superelastic Nickel-Titanium Rhombic Dodecahedron Structure Using The Finite Element Method, Ian Patrick Morrissey Apr 2022

Numerical Studies Of A Superelastic Nickel-Titanium Rhombic Dodecahedron Structure Using The Finite Element Method, Ian Patrick Morrissey

Master's Theses (2009 -)

Energy dissipation is an important material property for materials used inapplications such as armor, airplane wings, and automotive vehicle crumple zones. superelastic Nickel-Titanium (NiTi) and compliant under-dense materials both have excellent energy dissipation properties. Current research suggests that compliant underdense materials made of superelastic NiTi have desirable energy dissipation properties. A rhombic dodecahedron Lattice Structured Material (LSM) is an example of a compliant under-dense Material which has potential to exhibit desirable energy dissipation properties when manufactured from superelastic NiTi. In this work, finite element modeling of a superelastic NiTi rhombic dodecahedron Lattice Structured Material is performed and an optimum for …


Environmental Effects On Self-Luminous Gfrps, Michael Charles Phelan Apr 2022

Environmental Effects On Self-Luminous Gfrps, Michael Charles Phelan

Master's Theses (2009 -)

By implanting luminous powder into GFRPs, the material’s luminous capabilities coupled with its high strength to weight ratio create a structural component doubling as a sustainable light source. In this research, the luminous and mechanical properties of self-luminous GFRPs subjected to various environmental stimuli are studied to understand how their afterglow and mechanical properties are affected by weather and differing luminous powder concentrations. To simulate the conditions a GFRP will face during its lifetime, the material was studied after exposure to UV radiation, freezing and hot temperatures, and submersion under tap water. This study also analyzes how the luminous and …


Barriers To Utilization Of Fare-Free Transit By Students, Danielle Eden Del Conte Apr 2022

Barriers To Utilization Of Fare-Free Transit By Students, Danielle Eden Del Conte

Master's Theses (2009 -)

Marquette University has participated in Milwaukee County Transit System's (MCTS) U-PASS program since 1995. The program provides fare-free access to buses for students via an unlimited pass paid for by a $50 per semester fee. Marquette University pays MCTS a lump sum each year, heavily discounting the cost-per-ride for students if they were to pay out-of-pocket for bus tickets. Unlimited Access (UA) programs on college campuses are a win-win-win situation for students, universities, and transit agencies, decreasing student costs, reducing on-campus parking demand, and increasing transit funding and ridership. Despite the reported benefits, ridership from the U-PASS program has decreased …


Impact Of Corrosion Inhibitors And Metals On Antibiotic Resistance In Drinking Water Distribution Systems, Lee Kimbell Apr 2022

Impact Of Corrosion Inhibitors And Metals On Antibiotic Resistance In Drinking Water Distribution Systems, Lee Kimbell

Dissertations (1934 -)

Drinking water distribution systems are important for transporting clean drinking water. Antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) in drinking water may pose risks to human and environmental health. Aging infrastructure such as metal pipes can experience significant corrosion, which can have impacts on the chemical and microbial water quality inside of drinking water systems. Chemicals are commonly added to drinking water to prevent corrosion (i.e., corrosion inhibitors). The metal pipe materials and corrosion inhibitors containing metals may have impacts on the bacteria and ARGs in drinking water systems. This research investigated the presence of ARGs in real-world …


Evaluation Of Shoulder Complex Kinematics Pre And Post Rotator Cuff Repair And Effects Of Altering Rotation Sequence, Alyssa Joy Schnorenberg Apr 2022

Evaluation Of Shoulder Complex Kinematics Pre And Post Rotator Cuff Repair And Effects Of Altering Rotation Sequence, Alyssa Joy Schnorenberg

Dissertations (1934 -)

Approximately 25% of adults in the United States will sustain a rotator cuff tear in their lifetime. Rotator cuff tears can impede one's ability to perform activities of daily living and maintain functional independence. Nearly 300,000 rotator cuff repair surgeries are performed annually and aim to decrease pain, increase range of motion, and enable return to the workforce.The goal of postoperative rehabilitation is to allow healing of the repaired cuff while restoring function and range of motion, but it is demanding and may require a year. However, most rehabilitation protocols are based solely on clinical experience rather than on evidence-based …


Eeg During Motor Tasks In Stroke: The Effects Of Remote Ischemic Conditioning And Fatigue On Brain Activity, Priya Balasubramanian Apr 2022

Eeg During Motor Tasks In Stroke: The Effects Of Remote Ischemic Conditioning And Fatigue On Brain Activity, Priya Balasubramanian

Dissertations (1934 -)

This dissertation aimed to use electroencephalography (EEG) to identify the effects of fatigue and remote ischemic conditioning on brain activity. Lesions due to stroke directly or indirectly affect regions of the brain and the descending corticospinal pathways. Cortical reorganization and alternate descending neural pathways are used during recovery from stroke as compensation mechanisms for motor deficits. These mechanisms exacerbate the deficits by worsening the ability to terminate muscle activity, individuate muscles for fine motor control and minimize abnormal muscle synergy and coactivation patterns to conserve resources during movement. Even though imaging and muscle activation studies have documented the existence and …


Post Aerobic Digestion (Pad) Is A Solids Sidestream Nutrient Removal Process That Utilizes Native Carbon: Performance And Key Operational Parameters From Two Full-Scale Pad Reactors, Patrick J. Mcnamara, Fabrizio Sabba, Eric Redmond, Patrick Dunlap, Thomas Worley-Morse, Christopher Marks, Leon Downing Apr 2022

Post Aerobic Digestion (Pad) Is A Solids Sidestream Nutrient Removal Process That Utilizes Native Carbon: Performance And Key Operational Parameters From Two Full-Scale Pad Reactors, Patrick J. Mcnamara, Fabrizio Sabba, Eric Redmond, Patrick Dunlap, Thomas Worley-Morse, Christopher Marks, Leon Downing

Civil and Environmental Engineering Faculty Research and Publications

Nutrient management is a critical issue for Water Resource Recovery Facilities, and sidestream treatment technologies to reduce nutrient loads often focus on liquid sidestreams and require external carbon sources. Post aerobic digestion (PAD), whereby an aerobic digester follows an anaerobic digester, treats a solids stream (i.e., anaerobic digester effluent) to reduce nitrogen loads. Volatile solids reduction occurs in this process with residual organic compounds serving as a native carbon source for denitrification. While this process has been evaluated at the lab-scale, information on operational parameters that affect full-scale performance is limited. We evaluated two separate full-scale PAD reactors …


Microstructural Characteristics And Mechanical Properties Of Additively Manufactured Cu–10sn Alloys By Laser Powder Bed Fusion, Abhishek Mehta, Le Zhou, Holden Hyer, Thinh Huynh, Binghao Lu, Erica J. Drobner, Sun Hong Park, Yongho Sohn Mar 2022

Microstructural Characteristics And Mechanical Properties Of Additively Manufactured Cu–10sn Alloys By Laser Powder Bed Fusion, Abhishek Mehta, Le Zhou, Holden Hyer, Thinh Huynh, Binghao Lu, Erica J. Drobner, Sun Hong Park, Yongho Sohn

Mechanical Engineering Faculty Research and Publications

Cu – 10 wt% Sn (Cu–10Sn) alloy specimens were additively manufactured by varying the laser powder bed fusion (LBPF) processing parameters, e.g., laser power (200–350 W) and laser scan speed (100–1400 mm/s) at a fixed hatch spacing (0.12 mm) and slice thickness (0.03 mm), to examine their effects on the density, melt pool structure, and microstructure. Microstructural characteristics of the most dense sample were examined using electron microscopy (SEM, TEM) and X-ray Diffraction. The grains in the top-most melt pool layer showed a fan-like structure, whereas all other areas showed small columnar structure aligned nearly parallel to the build direction …


Elimination Of Extraordinarily High Cracking Susceptibility Of Aluminum Alloy Fabricated By Laser Powder Bed Fusion, Holden Hyer, Le Zhou, Sharon Park, Thinh Huynh, Abhishek Mehta, Saket Thapliyal, Rajiv S. Mishra, Yongho Sohn Mar 2022

Elimination Of Extraordinarily High Cracking Susceptibility Of Aluminum Alloy Fabricated By Laser Powder Bed Fusion, Holden Hyer, Le Zhou, Sharon Park, Thinh Huynh, Abhishek Mehta, Saket Thapliyal, Rajiv S. Mishra, Yongho Sohn

Mechanical Engineering Faculty Research and Publications

Using the calculation of phase diagrams approach and Scheil solidification modeling, the Al-2.5Mg-1.0Ni-0.4Sc-0.1Zr alloy was designed, intentionally with an extraordinarily high cracking susceptibility, making it prime for solidification cracking during laser powder bed fusion. This study demonstrates the ability to mitigate even the most extreme solidification cracking tendencies in aluminum alloys with only minor alloying additions of Sc and Zr, 0.5 wt.% max. Furthermore, by employing a simple direct ageing heat treatment, good tensile mechanical properties were observed with a yield strength of 308 MPa, an ultimate tensile strength of 390 MPa, and a total elongation of 11%.


Inverted Reactivity Controlled Compression Ignition (Ircci) With Methanol Fuel & Reactivity Enhancers, Musharrat Chowdhury, Adam Dempsey Mar 2022

Inverted Reactivity Controlled Compression Ignition (Ircci) With Methanol Fuel & Reactivity Enhancers, Musharrat Chowdhury, Adam Dempsey

Mechanical Engineering Faculty Research and Publications

Reactivity Controlled Compression Ignition (RCCI) is a low temperature combustion regime that has demonstrated ultra-low NOx and soot while achieving high thermal efficiency. RCCI uses a low reactivity premixed charge which is ignited via direct injection of a high reactivity fuel. The aim is to create a nearly homogeneous charge but maintain control over the combustion timing via the ratio between the premixed and direct injected fuel, hence controlling global reactivity via reactivity gradients in-cylinder. RCCI combustion with gasoline as the premixed fuel and diesel as the high reactivity fuel has shown good combustion timing controllability. However, RCCI with alcohol …


Eeg And Fmri Coupling And Decoupling Based On Joint Independent Component Analysis (Jica), Nicholas Heugel, Scott A. Beardsley, Einat Liebenthal Mar 2022

Eeg And Fmri Coupling And Decoupling Based On Joint Independent Component Analysis (Jica), Nicholas Heugel, Scott A. Beardsley, Einat Liebenthal

Biomedical Engineering Faculty Research and Publications

Background

Meaningful integration of functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) requires knowing whether these measurements reflect the activity of the same neural sources, i.e., estimating the degree of coupling and decoupling between the neuroimaging modalities.

New method

This paper proposes a method to quantify the coupling and decoupling of fMRI and EEG signals based on the mixing matrix produced by joint independent component analysis (jICA). The method is termed fMRI/EEG-jICA.

Results

fMRI and EEG acquired during a syllable detection task with variable syllable presentation rates (0.25–3 Hz) were separated with jICA into two spatiotemporally distinct components, a primary …


Modeling Multimodal Access To Primary Care In An Urban Environment, Danielle Eden Del Conte, Amanda Locascio, Joseph Amoruso, Margaret L. Mcnamara Mar 2022

Modeling Multimodal Access To Primary Care In An Urban Environment, Danielle Eden Del Conte, Amanda Locascio, Joseph Amoruso, Margaret L. Mcnamara

Civil and Environmental Engineering Faculty Research and Publications

Access to primary health care facilities is a key component of public health, and measuring that access is vital to understanding how to target interventions. Transportation is one dimension of access and measuring distance via multiple modes allows better understanding of how varied populations access health care, particularly those who do not have access to a personal vehicle. This work builds on the 2-Step Floating Catchment Area (2SFCA) method to include travel by car, bus, bicycle, and walking. Travel time data are sourced from OpenStreetMap and transit data incorporates stop and schedule information from the General Transit Feed Specification (GTFS). …


High-Resistance Connection Diagnosis In Five-Phase Pmsms Based On The Method Of Magnetic Field Pendulous Oscillation And Symmetrical Components, Hao Chen, Jiangbiao He, Xing Guan, Nabeel Demerdash, Ayman M. El-Refaie, Christopher H.T. Lee Mar 2022

High-Resistance Connection Diagnosis In Five-Phase Pmsms Based On The Method Of Magnetic Field Pendulous Oscillation And Symmetrical Components, Hao Chen, Jiangbiao He, Xing Guan, Nabeel Demerdash, Ayman M. El-Refaie, Christopher H.T. Lee

Electrical and Computer Engineering Faculty Research and Publications

An online approach for diagnosing high-resistance connection (HRC) faults in five-phase permanent magnet synchronous motor drives is presented in this article. The development of this approach is based on a so-called “magnetic field pendulous oscillation (MFPO)” technique and symmetrical components method. Under HRC fault condition, a “swing-like” MFPO phenomenon is observed compared to the healthy condition. Furthermore, with the extracted current features in symmetrical components domain, different HRC fault types are successfully identified and distinguished. These fault types include single-phase faults, e.g., HRC fault in phase-A; two-phase nonadjacent faults, e.g., HRC fault in phase-A&C; and two-phase adjacent faults, e.g., HRC …


A Continuum Damage Approach To Spallation And The Role Of Microinertia, S. B. Qamar, John A. Moore, Nathan R. Barton Feb 2022

A Continuum Damage Approach To Spallation And The Role Of Microinertia, S. B. Qamar, John A. Moore, Nathan R. Barton

Mechanical Engineering Faculty Research and Publications

Spall failure is of interest due to its prevalence in high strain rate problems in which the spallation is driven by the interaction of release waves. In this article, a porosity-based damage model that includes microinertial effects is used to examine spall failure. The model is successfully calibrated to plate impact-driven experiments and then used to evaluate experimental conditions producing more extreme strain rate conditions, such as those in laser-driven experiments. The incorporation of microinertia allows us to better understand the increase in apparent macroscopic spall strength seen at high strain rates. Correspondingly, we conclude that the incorporation of microinertial …


Glycerol-Driven Denitratation: Process Kinetics, Microbial Ecology, And Operational Controls, Matthew Baideme, Chenghua Long, Luke Plante, Jeffrey A. Starke, Michael A. Butkus, Katrik Chandran Feb 2022

Glycerol-Driven Denitratation: Process Kinetics, Microbial Ecology, And Operational Controls, Matthew Baideme, Chenghua Long, Luke Plante, Jeffrey A. Starke, Michael A. Butkus, Katrik Chandran

Civil and Environmental Engineering Faculty Research and Publications

Denitratation, the selective reduction of nitrate to nitrite, is a novel process and when coupled with anaerobic ammonium oxidation (anammox) could achieve resource-efficient biological nitrogen removal of ammonium- and nitrate-laden waste streams. Using a fundamentally-based, first principles approach, this study optimized a stoichiometrically-limited, glycerol-driven denitratation process and characterized mechanisms supporting nitrite accumulation with results that aligned with expectations. At the optimal influent chemical oxygen demand to nitrate ratio of 3.0 : 1 identified, glycerol supported selective nitrate reduction to nitrite (nitrite accumulation ratio, NAR = 62%) and near-complete nitrate conversion (nitrate reduction ratio, NRR = 96%), indicating its viability in …


Neural Control Of Stopping And Stabilizing The Arm, Shanie A. L. Jayasinghe, Robert A. Scheidt, Robert L. Sainburg Feb 2022

Neural Control Of Stopping And Stabilizing The Arm, Shanie A. L. Jayasinghe, Robert A. Scheidt, Robert L. Sainburg

Biomedical Engineering Faculty Research and Publications

Stopping is a crucial yet under-studied action for planning and producing meaningful and efficient movements. In this review, we discuss classical human psychophysics studies as well as those using engineered systems that aim to develop models of motor control of the upper limb. We present evidence for a hybrid model of motor control, which has an evolutionary advantage due to division of labor between cerebral hemispheres. Stopping is a fundamental aspect of movement that deserves more attention in research than it currently receives. Such research may provide a basis for understanding arm stabilization deficits that can occur following central nervous …


Assessment Of Protection Offered By The Nrf2 Pathway Against Hyperoxia-Induced Acute Lung Injury In Nrf2 Knockout Rats, Said H. Audi, Elizabeth R. Jacobs, Taheri Pardis, Swetha Ganesh, Anne V. Clough Feb 2022

Assessment Of Protection Offered By The Nrf2 Pathway Against Hyperoxia-Induced Acute Lung Injury In Nrf2 Knockout Rats, Said H. Audi, Elizabeth R. Jacobs, Taheri Pardis, Swetha Ganesh, Anne V. Clough

Biomedical Engineering Faculty Research and Publications

Nuclear factor erythroid 2-related factor (Nrf2) is a redox-sensitive transcription factor that responds to oxidative stress by activating expressions of key antioxidant and cytoprotective enzymes via the Nrf2-antioxidant response element (ARE) signaling pathway. Our objective was to characterize hyperoxia-induced acute lung injury (HALI) in Nrf2 knock-out (KO) rats to elucidate the role of this pathway in HALI. Adult Nrf2 wildtype (WT), and KO rats were exposed to room air (normoxia) or >95% O2 (hyperoxia) for 48 h, after which selected injury and functional endpoints were measured in vivo and ex vivo. Results demonstrate that the Nrf2-ARE signaling pathway …


Paper Mill Sludge Biochar To Enhance Energy Recovery From Pyrolysis: A Comprehensive Evaluation And Comparison, Zhongzhe Liu, Matthew Hughes, Yiran Tong, William Kreutter, Hugo Cortes Lopez, Simcha L. Singer, Daniel Zitomer, Patrick J. Mcnamara Jan 2022

Paper Mill Sludge Biochar To Enhance Energy Recovery From Pyrolysis: A Comprehensive Evaluation And Comparison, Zhongzhe Liu, Matthew Hughes, Yiran Tong, William Kreutter, Hugo Cortes Lopez, Simcha L. Singer, Daniel Zitomer, Patrick J. Mcnamara

Civil and Environmental Engineering Faculty Research and Publications

Bio-oil and pyrolysis gas (py-gas) are two pyrolysis products available for potential energy recovery. Crude bio-oil, however, is typically corrosive and unstable, requiring special combustion equipment or catalytic upgrading to produce drop-in-grade fuel. In contrast, py-gas is readily useable in standard equipment for energy recovery. Previous research revealed that Ca-impregnated biochar catalyst improved bio-oil to py-gas conversion. Biochar produced from paper mill sludge (p-sludge) has very high Ca content. In this study, the catalytic ability of p-sludge biochar was systematically evaluated for the first time in pyrolysis. P-sludge biochar resulted in higher py-gas yield (40 wt% of total pyrolysis products) …


Microstructural Development In Inconel 718 Nickel-Based Superalloy Additively Manufactured By Laser Powder Bed Fusion, Thinh Huynh, Abhishek Mehta, Kevin Graydon, Jeongmin Woo, Sharon Park, Holden Hyer, Le Zhou, D. Devin Imholte, Nicolas E. Woolstenhulme, Daniel M. Wachs, Yongho Sohn Jan 2022

Microstructural Development In Inconel 718 Nickel-Based Superalloy Additively Manufactured By Laser Powder Bed Fusion, Thinh Huynh, Abhishek Mehta, Kevin Graydon, Jeongmin Woo, Sharon Park, Holden Hyer, Le Zhou, D. Devin Imholte, Nicolas E. Woolstenhulme, Daniel M. Wachs, Yongho Sohn

Mechanical Engineering Faculty Research and Publications

Excellent weldability and high temperature stability make Inconel 718 (IN718) one of the most popular alloys to be produced by additive manufacturing. In this study, we investigated the effects of laser powder bed fusion (LPBF) parameters on the microstructure and relative density of IN718. The samples were fabricated with independently varied laser power (125–350 W), laser scan speed (200–2200 mm/s), and laser scan rotation (0°–90°). Archimedes’ method, optical microscopy, and scanning electron microscopy were employed to assess the influence of LPBF parameters on the relative density and microstructure. Optimal processing windows were identified for a wide range of processing parameters, …


The Relationship Between Mechanism Geometry And The Centers Of Stiffness And Compliance, Shuguang Huang, Joseph M. Schimmels Jan 2022

The Relationship Between Mechanism Geometry And The Centers Of Stiffness And Compliance, Shuguang Huang, Joseph M. Schimmels

Mechanical Engineering Faculty Research and Publications

A significant amount of research has been directed toward developing a more intuitive appreciation of spatial elastic behavior. Results of these analyses have often been described in terms of the elastic behavior (stiffness or compliance) centers. This paper investigates the properties of centers of stiffness and compliance and provides a fresh view of elastic center locations, specifically, the locus of centers associated with a given mechanism’s topology and geometry. We show that the location of the center of stiffness (compliance) for a set of elastic components connected in parallel (in serial) can be described in terms similar to the …


Acute Magnetic Resonance Imaging Predictors Of Chronic Motor Function And Tissue Sparing In Rat Cervical Spinal Cord Injury, Seung-Yi Lee, Brian D. Schmit, Shekar N. Kurpad, Matthew D. Budde Jan 2022

Acute Magnetic Resonance Imaging Predictors Of Chronic Motor Function And Tissue Sparing In Rat Cervical Spinal Cord Injury, Seung-Yi Lee, Brian D. Schmit, Shekar N. Kurpad, Matthew D. Budde

Biomedical Engineering Faculty Research and Publications

Predicting functional outcomes from spinal cord injury (SCI) at the acute setting is important for patient management. This work investigated the relationship of early magnetic resonance imaging (MRI) biomarkers in a rat model of cervical contusion SCI with long-term functional outcome and tissue sparing. Forty rats with contusion injury at C5 at either the spinal cord midline (bilateral) or over the lateral cord (unilateral) were examined using in vivo multi-modal quantitative MRI at 1 day post-injury. The extent of T2-weighted hyperintensity reflecting edema was greater in the bilateral model compared with the unilateral injury. Diffusion tensor imaging (DTI) …


Effect Of Joint Rotation On Curling Responses In Airfield Rigid Pavements, Jaime Hernandez, Imad L. Al-Qadi Jan 2022

Effect Of Joint Rotation On Curling Responses In Airfield Rigid Pavements, Jaime Hernandez, Imad L. Al-Qadi

Civil and Environmental Engineering Faculty Research and Publications

This paper quantifies the relevance of restriction to joint rotation of an airfield concrete pavement when calculating critical curling stresses and deflections using a validated finite element model. The validation uses strains measured at the John F. Kennedy International Airport. To calculate critical curling stresses and deflections, the pavement was subjected to 5263 h of temperature variation determined by utilising the enhanced integrated climate model and thermocouple readings. The profiles include a wide range of average temperatures, temperature gradients, and temperature nonlinearity. Three conditions were included: (1) joints free to displace and rotate; (2) joints free to rotate, but partially …