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2020

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Articles 8401 - 8430 of 10642

Full-Text Articles in Engineering

Effect Of Subsurface Microseismicity On The Motion Of Surrounding Dispersed Droplets: Supporting Information, Chao Zeng, Wen Deng Jan 2020

Effect Of Subsurface Microseismicity On The Motion Of Surrounding Dispersed Droplets: Supporting Information, Chao Zeng, Wen Deng

Research Data

The human-induced seismicity has called substantial attention in recent years. The effect of seismicity on the subsurface structure has been extensively studied. However, the effect of seismicity, especially those microseismicity, on surrounding immiscible fluids is rarely investigated. In porous media with two or more immiscible fluids, different amplitudes of vibration induced by seismicity have distinct effects on the dynamic behavior of fluids. Three types of pore-scale models are prevalent in the analysis of the motion of immiscible droplets. The underlying assumptions and accuracy of these models are compared in this study in both frequency domain and time domain. The frequency …


Numerical Study Of Paramagnetic Elliptical Microparticles In Curved Channels And Uniform Magnetic Fields, Christopher Sobecki, Jie Zhang, Cheng Wang Jan 2020

Numerical Study Of Paramagnetic Elliptical Microparticles In Curved Channels And Uniform Magnetic Fields, Christopher Sobecki, Jie Zhang, Cheng Wang

Mechanical and Aerospace Engineering Faculty Research & Creative Works

We numerically investigated the dynamics of a paramagnetic elliptical particle immersed in a low Reynolds number Poiseuille flow in a curved channel and under a uniform magnetic field by direct numerical simulation. A finite element method, based on an arbitrary Lagrangian-Eulerian approach, analyzed how the channel geometry, the strength and direction of the magnetic field, and the particle shape affected the rotation and radial migration of the particle. The net radial migration of the particle was analyzed after executing a π rotation and at the exit of the curved channel with and without a magnetic field. In the absence of …


Monitoring Methods And Performance Assessment For Implementation Of Low Impact Development Practices In South Dakota, Farhana Akhter Jan 2020

Monitoring Methods And Performance Assessment For Implementation Of Low Impact Development Practices In South Dakota, Farhana Akhter

Electronic Theses and Dissertations

Urbanization increases impervious surface area, which changes the hydrology of a watershed. Impervious surfaces prevent the infiltration of stormwater water into the ground surface which results in a higher volume of stormwater runoff and higher peak flow. Low Impact Development (LID) practices help to restore pre-development hydrology by increasing infiltration, evaporation, and transpiration. While the hydrologic performance of LID practices has been studied extensively and continues to be an area of active research, there has been very limited monitoring or demonstration of LID practices in South Dakota. In addition, municipalities in South Dakota and elsewhere that implement new LID practices …


Vicarious Methodologies To Assess And Improve The Quality Of The Optical Remote Sensing Images: A Critical Review, Sakib Kabir Jan 2020

Vicarious Methodologies To Assess And Improve The Quality Of The Optical Remote Sensing Images: A Critical Review, Sakib Kabir

Electronic Theses and Dissertations

Over the past decade, number of optical Earth observing satellites performing remote sensing has increased substantially, dramatically increasing the capability to monitor the Earth. The quantity of remote sensing satellite increase is primarily driven by improved technology, miniaturization of components, reduced manufacturing, and launch cost. These satellites often lack on-board calibrators that a large satellite utilizes to ensure high quality (e.g., radiometric, geometric, spatial quality, etc.) scientific measurement. To address this issue, this work presents “best” vicarious image quality assessment and improvement techniques for those kinds of optical satellites which lacks on-board calibration system. In this article, image quality categories …


A Brief Review On 3d Bioprinted Skin Substitutes, Fateme Fayyazbakhsh, Ming-Chuan Leu Jan 2020

A Brief Review On 3d Bioprinted Skin Substitutes, Fateme Fayyazbakhsh, Ming-Chuan Leu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The Global Escalating Cases of Skin Donor Shortage for Patients with Severe Wounds Warn the Vital Need for Alternatives to Skin Allografts. over the Last Three Decades, Research in the Skin Regeneration Area Has Addressed the Unmet Need for Artificial Skin Substitutes. 3D Bioprinting is a Promising Innovative Technology to Accurately Fabricate Skin Constructs based on Natural or Synthetic Bioinks, Whether Loaded or Not Loaded with Native Skin Cells (I.e., Keratinocytes and Fibroblasts) or Stem Cells in the Prescribed 3D Hierarchal Structure to Create Artificial Multilayer and Single Cell-Laden Construct. in This Paper, the Recent Developments in 3D Bioprinting for …


Lithium-Ion Battery And Beyond: Oxygen Vacancy Creation In Tungsten Trioxide And Surface Modification Of Lithium Metal, Rajesh Pathak Jan 2020

Lithium-Ion Battery And Beyond: Oxygen Vacancy Creation In Tungsten Trioxide And Surface Modification Of Lithium Metal, Rajesh Pathak

Electronic Theses and Dissertations

The graphite-based anode material has a low theoretical specific capacity of 371 mAh g-1. The transitional metal oxides (TMOs) are considered a better choice owing to their relatively higher specific capacity. Among TMOs, tungsten trioxide (WO3) is considered promising due to a higher specific capacity of 693 mAh g-1, low cost, mechanically stable, and eco-friendly. It has been a challenge to utilize the TMOs as anode materials as they suffer from poor electronic conductivity and large electrode volume expansion during discharge/charge cycles. In our first project, we demonstrate a unique self-recovery of capacity in reduced WO3 by the incorporation of …


Emulsion Stability Of Heavy Oil With Surfactants And Nanoparticles, Zainab Abdulmohsein, Baojun Bai, Parthasakha Neogi Jan 2020

Emulsion Stability Of Heavy Oil With Surfactants And Nanoparticles, Zainab Abdulmohsein, Baojun Bai, Parthasakha Neogi

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The recovered crude oil is often in form of an emulsion and the recovery is cut off when water to oil ratio exceeds a certain amount. The emulsions vary from water-in-oil to oil-in-water and the step that follows is to coalesce droplets to get two continuous liquids. Difficulties arise when the oil contains emulsifiers. There are naturally occurring surfactants, or the oil recovered is by enhanced oil recovery techniques which have additives that stabilize the droplets. We have considered below a heavy oil (viscosity 650-750 mPa.s) containing one of the three surfactants: a nonionic surfactant or a cationic surfactant or …


Soil Fatigue From Induced Seismicity, Merissa L. Zuzulock, Oliver Denzil S. Taylor, Norbert H. Maerz Jan 2020

Soil Fatigue From Induced Seismicity, Merissa L. Zuzulock, Oliver Denzil S. Taylor, Norbert H. Maerz

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Induced seismicity and the effects on civil engineering systems are not completely understood and infrequently studied. One specific area that is not well known is soil fatigue which includes factors such as understanding the natural conditions of the subsurface as well as operational parameters under short duration impulse loads. With the increase of Geo induced seismic activity, soil fatigue becomes of greater concern to structures in the vicinity of this seismic load. The foundations of these structures can be affected by impulse loads which can ultimately cause failure. The lack of quantitative data puts the reliability of these civil engineering …


Influence Of Pumping Pressure On The Viscosity Curve And Rheological Stability Of Mortar Incorporating Polycarboxylate, Jae Hong Kim, Seong Ho Han, Byoung Il Choi Jan 2020

Influence Of Pumping Pressure On The Viscosity Curve And Rheological Stability Of Mortar Incorporating Polycarboxylate, Jae Hong Kim, Seong Ho Han, Byoung Il Choi

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Concrete pumping has been successfully adopted in modern construction. Various concrete including high-strength concrete and self-consolidating concrete can be pumped, but we still have a lack of understanding of the rheological behavior and its change during the pumping process. This study evaluates the effect of pumping pressure on the viscosity curves of cement-based materials incorporating a specific polycarboxylate. The viscosity of mortar samples increases with the pumping pressure. The viscosity increase depends on the rate of shear strain and the polymer structure of the polycarboxylate. The effect of pumping pressure is then generalized with a Sisko model. A mechanistic model …


Patch-Based Gaussian Mixture Model For Scene Motion Detection In The Presence Of Atmospheric Optical Turbulence, Richard L. Van Hook, Russell C. Hardie Jan 2020

Patch-Based Gaussian Mixture Model For Scene Motion Detection In The Presence Of Atmospheric Optical Turbulence, Richard L. Van Hook, Russell C. Hardie

Electrical and Computer Engineering Faculty Publications

In long-range imaging regimes, atmospheric turbulence degrades image quality. In addition to blurring, the turbulence causes geometric distortion effects that introduce apparent motion in acquired video. This is problematic for image processing tasks, including image enhancement and restoration (e.g., superresolution) and aided target recognition (e.g., vehicle trackers). To mitigate these warping effects from turbulence, it is necessary to distinguish between actual in-scene motion and apparent motion caused by atmospheric turbulence. Previously, the current authors generated a synthetic video by injecting moving objects into a static scene and then applying a well-validated anisoplanatic atmospheric optical turbulence simulator. With known per-pixel truth …


Covid-19 And Public Transportation: Current Assessment, Prospects, And Research Needs, Alejandro Tirachini, Oded Cats Jan 2020

Covid-19 And Public Transportation: Current Assessment, Prospects, And Research Needs, Alejandro Tirachini, Oded Cats

Journal of Public Transportation

The COVID-19 pandemic poses a great challenge for contemporary public transportation worldwide, resulting from an unprecedented decline in demand and revenue. In this paper, we synthesize the state-of-the-art, up to early June 2020, on key developments regarding public transportation and the COVID-19 pandemic, including the different responses adopted by governments and public transportation agencies around the world, and the research needs pertaining to critical issues that minimize contagion risk in public transportation in the so-called post-lockdown phase. While attempts at adherence to physical distancing (which challenges the very concept of mass public transportation) are looming in several countries, the latest …


Extracting Bus Transit Boarding And Alighting Information Using Smart Card Transaction Data, Zhen Chen, Wei Fan Jan 2020

Extracting Bus Transit Boarding And Alighting Information Using Smart Card Transaction Data, Zhen Chen, Wei Fan

Journal of Public Transportation

The smart card–based automated fare collection (AFC) technologies provide new opportunities for transportation data collection since smart card data (SCD) contain a significant amount of archived information that can be gathered and leveraged to help estimate public transit origin-destination (OD) matrices. Both boarding and alighting location detection are important particularly when there is no automatic vehicle location (AVL) system or other information in the database. With the analysis of raw data using limited information in this paper, an algorithm for boarding stop identification is presented after the trip direction and boarding cluster identification. Alighting stops are then identified based on …


Development Of High-Power Single-Mode Yb-Doped Fiber Amplifiers And Beam Analysis, Steffen Wittek Jan 2020

Development Of High-Power Single-Mode Yb-Doped Fiber Amplifiers And Beam Analysis, Steffen Wittek

Electronic Theses and Dissertations, 2020-2023

High-power fiber laser systems enjoy a widespread use in manufacturing, medical, and defense applications as well as scientific research, due to their remarkable power scalability, high electrical to optical efficiency, compactness and ruggedness. However, single-mode fiber power scaling has stagnated in the past years, primarily due to the onset of nonlinear effects such as stimulated Brillouin/Raman scattering and transverse modal instabilities. This thesis addresses the analysis and mitigation of transverse modal instabilities in high-power fiber amplifiers. I describe the high-power fiber amplifier testbed that I set up to test fibers fabricated in house. I will show our results of a …


Design Of An Annular Disc-Shaped Heat Pipe For Air-Cooled Steam Condensers, Ahmad Saleh Jan 2020

Design Of An Annular Disc-Shaped Heat Pipe For Air-Cooled Steam Condensers, Ahmad Saleh

Electronic Theses and Dissertations, 2020-2023

Limitations on water utilization are turning into an expanding issue for the power and electricity generation industry. As a contribution to the solution of water consumption problems, utility companies are shifting toward using air-cooled condensers (ACC) in replace to the typical water-cooling methods of once-through cooling and the surface condenser/wet-cooling tower combination. Although the ACC is a dry cooling method, the industry is quite hesitant to switch over to ACC mainly for three reasons: (a) lower power output, (b) higher capital cost, and (c) larger physical footprint. All these drawbacks are because of the high overall thermal resistance of condensing …


Development Of Facile Microfabrication Technologies For The Fabrication And Characterization Of Multimodal Impedimetric, Plasmonic, And Electrophysiological Biosensors, Cacie Hart Jan 2020

Development Of Facile Microfabrication Technologies For The Fabrication And Characterization Of Multimodal Impedimetric, Plasmonic, And Electrophysiological Biosensors, Cacie Hart

Electronic Theses and Dissertations, 2020-2023

The objective of this dissertation was to develop novel methods of patterning inorganic and organic materials, develop biocompatibility evaluations, and subsequently apply these methods toward developing biosensors and lab-on-a-chip devices, such as Interdigitated Electrodes (IDEs) and Microelectrode Arrays (MEAs) on non-traditional (such as nanostructured and plasmonic) polymer substrates or deploy these methods to enhance precision cellular placement on traditional (glass) MEA substrates. It was hypothesized that a combination of such facile microfabrication techniques and patterning technologies on traditional and non-traditional substrates would increase the sensitivity and selectivity of such sensor platforms by several orders of magnitude, and potentially introduce new …


Mobility-As-A-Service: Assessing Performance And Sustainability Effects Of An Integrated Multi-Modal Simulated Transportation Network, Mohamed El-Agroudy Jan 2020

Mobility-As-A-Service: Assessing Performance And Sustainability Effects Of An Integrated Multi-Modal Simulated Transportation Network, Mohamed El-Agroudy

Electronic Theses and Dissertations, 2020-2023

Advances in information technology services have seen profound impacts on the state of transport services in the urban traffic environment. Mobility-as-a-Service (MaaS) represents the digital consolidation of users, operators, and public-private managing entities to provide totally comprehensive, integrated trip-making services. Users now enjoy extra flexibility for trip-making with new modal alternatives such as micro-mobility (e.g Lime Bikes, Spin Scooters) and rideshare (e.g. Lyft, Uber). However, current knowledge on the performance and interactive effects of these newer alternative modes is vague if not inconsistent. As such, these effects were studied through micro-simulation analysis of a multi-modal urban corridor in Orlando, Florida. …


Novel Computational Approaches For Multidimensional Brain Image Analysis, Harish Raviprakash Jan 2020

Novel Computational Approaches For Multidimensional Brain Image Analysis, Harish Raviprakash

Electronic Theses and Dissertations, 2020-2023

The overall goal of this dissertation is focused on addressing challenging problems in 1D, 2D/3D and 4D neuroimaging by developing novel algorithms that combine signal processing and machine learning techniques. One of these challenging tasks is the accurate localization of the eloquent language cortex in brain resection pre-surgery patients. This is especially important since inaccurate localization can lead to diminshed functionalities and thus, a poor quality of life for the patient. The first part of this dissertation addresses this problem in the case of drug-resistant epileptic patients. We propose a novel machine learning based algorithm to establish an alternate electrical …


Evaluation Of Safety And Mobility Benefits Of Connected And Automated Vehicles By Considering V2x Technologies, Md Hasibur Rahman Jan 2020

Evaluation Of Safety And Mobility Benefits Of Connected And Automated Vehicles By Considering V2x Technologies, Md Hasibur Rahman

Electronic Theses and Dissertations, 2020-2023

The recent development in communication technologies facilitates the deployment of connected and automated vehicles (CAV) which are expected to change the future transportation system. CAV technologies enable vehicles to communicate with other vehicles through vehicle-to-vehicle (V2V) communications and the infrastructure through Vehicle-to-infrastructure (V2I) communications. Since the real-world CAV data is not currently available as of today, simulation is the most commonly used platform to evaluate the future V2X system. Although several studies evaluated the effectiveness of CAVs in a small roadway network, there is a lack of studies analyzing the impact of CAVs at the network level by considering both …


Factors Affecting The Performance Of Photo-Voltaic Solar Energy Storage, Vasanth Bhat Jan 2020

Factors Affecting The Performance Of Photo-Voltaic Solar Energy Storage, Vasanth Bhat

Electronic Theses and Dissertations, 2020-2023

One of the most important factors in a nation's development is energy availability. All the aspects of its economy are directly proportional to the energy resources. Oil is one of the most sought energy resources currently. Solar energy is one of the most important renewable sources of energy available to us. With oil deposits depleting and current global warming, there is an emphasis on using more and more renewable sources or clean energy. This has led to immense research on solar cells and how it could better be used to get maximum output. Storage of energy is another aspect that …


Attosecond Transient Absorption Spectroscopy In The Water Window, Andrew Chew Jan 2020

Attosecond Transient Absorption Spectroscopy In The Water Window, Andrew Chew

Electronic Theses and Dissertations, 2020-2023

The push to study the atomic and molecular dynamics at ever smaller time scales has been the main driving force for developing laser systems with ever shorter pulse durations. Thus far, picosecond lasers and femtosecond lasers have been used with great success in femtochemistry to study molecular dynamics such as molecular rotation and vibration, which all occur in the tens to hundreds of femtosecond. To study electron dynamics however, which are on the order of attoseconds, one needs attosecond laser sources to be able to have the time resolution required to probe ultrafast electron dynamics such as AC Stark shifts, …


A Deep Learning Approach For Real-Time Crash Risk Prediction At Urban Arterials, Pei Li Jan 2020

A Deep Learning Approach For Real-Time Crash Risk Prediction At Urban Arterials, Pei Li

Electronic Theses and Dissertations, 2020-2023

Real-time crash risk prediction aims to predict the crash probabilities within a short time period, it is expected to play a crucial role in the advanced traffic management system. However, most of the existing studies only focused on freeways rather than urban arterials because of the complicated traffic environment of the arterials. This thesis proposes a long short-term memory convolutional neural network (LSTM-CNN) to predict the real-time crash risk at arterials. The advantage of this model is it can benefit from both LSTM and CNN. Specifically, LSTM captures the long-term dependency of the data while CNN extracts the time-invariant features. …


Nanofabrication And Characterization Of An Enzyme-Less Electrochemical Biosensor For Creatinine Detection, Anas Belharsa Jan 2020

Nanofabrication And Characterization Of An Enzyme-Less Electrochemical Biosensor For Creatinine Detection, Anas Belharsa

Electronic Theses and Dissertations, 2020-2023

This study will reveal the fabrication and development of an enzyme-less biosensor for creatinine detection. The biosensor involves a periodically patterned nano-porous TiO2 deposited with Au nanoparticles via e-beam evaporation and a layer of Imprinted Polymer (IP) of acrylamide and bis-acrylamide to obtain a heterostructure of I-Au-TiO2. The detection methods of creatinine are based on electrochemical measurements using Cyclic Voltammetry (CV), Electrochemical Impedance Spectroscopy (EIS) and Differential Pulse Voltammetry (DPV). The IP-Au-TiO2 sensor shows a detection LOD of 0.0949ng/mL and 0. 0.218ng/mL for EIS and DPV measurements, respectively. The nanofabricated biosensor was tested in the presents of urea, glucose, lactose, …


Nanotechnologies: A Review Of Inventions And Utility Models. Part V, L. A. Ivanov, L. D. Xu, E. S. Bokova, A. D. Ishkov Jan 2020

Nanotechnologies: A Review Of Inventions And Utility Models. Part V, L. A. Ivanov, L. D. Xu, E. S. Bokova, A. D. Ishkov

Information Technology & Decision Sciences Faculty Publications

The article provides an abstract review of patents. The results of creative activity of scientists, engineers and specialists, including inventions in the field of nanotechnology and nanomaterials, being implemented, allow achieving a significant effect in construction, housing and community services, and related sectors of the economy. For example, the invention "A method to produce dry construction mixtures" refers to manufacturing of building materials, in particularly, to manufacture of dry construction mixtures (DCM) by the method of joint mechanoactivation of cement and dolomite, with further modification of them with carbon nanostructures (CNT). The technical result of the given method of mixing …


Determinants Of Startup Funding: The Interaction Between Web Attention And Culture, Jie Ren, Viju Raghupathi, Wullianallur Raghupathi Jan 2020

Determinants Of Startup Funding: The Interaction Between Web Attention And Culture, Jie Ren, Viju Raghupathi, Wullianallur Raghupathi

Journal of International Technology and Information Management

Technology empowers entrepreneurs to pursue alternative funding through platforms like crowdfunding. This research explores significant startup funding factors using Crunchbase. Controlling for common factors (acquisition/funding-rounds/IPO), the research uniquely focuses on web attention - the visibility on social media - and its impact on funding. It also examines the moderating influence of startup’s home country culture (individualism/collectivism). Findings show stronger positive impact of web attention on startup funding for collectivist countries. While individualistic investors value personal goals, collectivists value collaborative goals - inclinations that align with crowdfunding behavior. Therefore while increasing web attention, crowdfunding efforts can be targeted towards collectivist countries.


Food Printing: Evolving Technologies, Challenges, Opportunities, And Best Adoption Strategies, Sharmin Attarin, Mohsen Attaran Jan 2020

Food Printing: Evolving Technologies, Challenges, Opportunities, And Best Adoption Strategies, Sharmin Attarin, Mohsen Attaran

Journal of International Technology and Information Management

3D printing is a process of making three-dimensional objects using additive processes where layers are laid down in succession to create a complete object. Companies across the globe are actively piloting and leveraging the inherent benefits of 3D printing technology. Today, 3D printing can revolutionize food innovation and production through better creativity, customizability, and sustainability. This article highlights 3D printing evolving technologies and trends and identifies its applications and implementation challenges. In this paper, we conducted a literature review to explore 3D printing's current technologies and applications in the food industry, including its advantages, its potential implications, and its obstacles …


Evaluating Students Information System Success Using Delone And Mclean’S Model: Student’S Perspective, Majaliwa Mkinga, Herman Mandari Jan 2020

Evaluating Students Information System Success Using Delone And Mclean’S Model: Student’S Perspective, Majaliwa Mkinga, Herman Mandari

Journal of International Technology and Information Management

System success is considered to be an important element in accomplishing the goals of the organization; therefore evaluation of system success needs to be done in order to ensure that investment in Information System is successful. Most of Higher Learning Institutions (HLIs) in Tanzania have adopted the use of IS in providing service to their customers. Nevertheless, there is less evidence that system success evaluation has been done in order to identify the desired characteristics which could make IS more effective. Due to that, this study evaluates the effectiveness of Student Information System (SIS) used at the Institute of Finance …


An Integrated View Of Data: Application Of Knowledge Modeling To Data Management, Sung-Kwan Kim, Wenjun Wang Jan 2020

An Integrated View Of Data: Application Of Knowledge Modeling To Data Management, Sung-Kwan Kim, Wenjun Wang

Journal of International Technology and Information Management

Data management has become an important challenge. Good data management requires an effective approach to collecting, storing, and accessing data across the enterprise. In this paper, a knowledge modeling approach to data management is introduced with an emphasis on data requirements analysis. A knowledge model can provide a high-level view of organizational data by specifying the structure and relationships of the knowledge contents used in business processes. The proposed knowledge modeling approach is business process oriented and decision oriented. The description of the knowledge contents in the model is based on ontological specification. The model is comprised of five elements: …


Uga’S Alexander Campbell King Law Library: Phasing In Inclusive Usability Testing, Rachel S. Evans, Marie Mize, Jason Tubinis Jan 2020

Uga’S Alexander Campbell King Law Library: Phasing In Inclusive Usability Testing, Rachel S. Evans, Marie Mize, Jason Tubinis

Articles, Chapters and Online Publications

For years we have offered our EBSCO discovery layer service (EDS) as a secondary search tool in addition to our traditional online catalog (GAVEL) linking to both from the library website. However, the traditional catalog search, also known as “Classic GAVEL”, is always listed first while EDS, also known as “GAVEL & Beyond”, is listed second. Although maintenance has continued for populating EDS with library records on a daily basis, customization for this interface and sharing it with our users has not been prioritized. Before making any decisions related to changing the primary location our users experience when searching the …


Electrospun Fibers With Smart Delivery Of Therapeutic Agents, Zahra Mahdieh Jan 2020

Electrospun Fibers With Smart Delivery Of Therapeutic Agents, Zahra Mahdieh

Graduate Student Theses, Dissertations, & Professional Papers

Electrospinning is the most widely studied technique of producing fibers. Delivery of nanoparticles and therapeutic agents from electrospun fibers have potential uses in various fields including drug delivery, filtration, and cosmetics. However, controlling the delivery rate remains the main challenge. In the current study, core-shell structure fibers were developed with zinc oxide nanoparticles applied in the shell composition to improve the pore structure (release pathway) and mechanical stability. Fine-tuned delivery rates were achieved via loading different sizes of silver nanoparticles (Ag NP) inside the fiber core. In vitro drug release assays showed fast, slow, and intermediate delivery rates of 20 …


A Comparison Of Zinc Levels In Runoff From Rubberized Hot Mix Asphalt And Conventional Pavement, Peter A. Duin Jan 2020

A Comparison Of Zinc Levels In Runoff From Rubberized Hot Mix Asphalt And Conventional Pavement, Peter A. Duin

Cal Poly Humboldt theses and projects

High levels of dissolved zinc in water bodies can be toxic to aquatic organisms. There are currently over 40 waterways in California that have on occasion been in exceedance of Clean Water Act minimum toxicity threshold standards for zinc. Recycled tires that contain 1-2% zinc by mass are commonly used in California paving formulations known as Rubberized Hot Mix Asphalt (RHMA). The addition of tires to RHMA increases the zinc content of the pavement in comparison to conventional HMA. This research assesses the zinc content and leaching rate of RHMA in field and laboratory settings to estimate its contribution of …