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2024

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Full-Text Articles in Chemical Engineering

Molecular Imaging Nanoprobes And Their Applications In Atherosclerosis Diagnosis, Huari Kou, Hu Yang Jan 2024

Molecular Imaging Nanoprobes And Their Applications In Atherosclerosis Diagnosis, Huari Kou, Hu Yang

Chemical and Biochemical Engineering Faculty Research & Creative Works

Molecular imaging has undergone significant development in recent years for its excellent ability to image and quantify biologic processes at cellular and molecular levels. Its application is of significance in cardiovascular diseases, particularly in diagnosing them at early stages. Atherosclerosis is a complex, chronic, and progressive disease that can lead to serious consequences such as heart strokes or infarctions. Attempts have been made to detect atherosclerosis with molecular imaging modalities. Not only do imaging modalities develop rapidly, but research of relevant nanomaterials as imaging probes has also been increasingly studied in recent years. This review focuses on the latest developments …


Injectable Dendrimer Hydrogel Delivers Melphalan In Both Conjugated And Free Forms For Retinoblastoma, Remy C. Cooper, Juan Wang, Hu Yang Jan 2024

Injectable Dendrimer Hydrogel Delivers Melphalan In Both Conjugated And Free Forms For Retinoblastoma, Remy C. Cooper, Juan Wang, Hu Yang

Chemical and Biochemical Engineering Faculty Research & Creative Works

We report the successful synthesis of an injectable dendrimer hydrogel (DH) carrying melphalan, a clinical drug for retinoblastoma treatment, in both conjugated and free forms. Polyamidoamine (PAMAM) dendrimer generation 5 (G5) is surface-modified with an acid-sensitive acetal-dibenzocyclooctyne linker and then undergoes azide-alkyne cycloaddition with melphalan-PEG-N3 conjugate to form G5-acetal-melphalan. During the DH gelation between G5-acetal-melphalan and PEG-diacrylate, free melphalan is added, resulting in a hydrogel (G5-acetal-melphalan-DH/melphalan) that carries the drug in both conjugated and free forms. Melphalan is slowly released from G5-acetal-melphalan-DH/melphalan, with the conjugated melphalan released more quickly at pH 5.3 due to acid-triggered acetal bond cleavage. The formulation's …


Magnetic Separation Of Lunar Regolith Simulants With Applications To In Situ Resource Utilization On The Moon, Peter Bachle, Jeffrey Smith, Fateme Rezaei, David Bayless, William Schonberg, Daoru Han Jan 2024

Magnetic Separation Of Lunar Regolith Simulants With Applications To In Situ Resource Utilization On The Moon, Peter Bachle, Jeffrey Smith, Fateme Rezaei, David Bayless, William Schonberg, Daoru Han

Chemical and Biochemical Engineering Faculty Research & Creative Works

The development of in situ resource utilization (ISRU) for metal extraction is imperative as a steppingstone for habitation construction in lunar and non-terrestrial environments. Separation of minerals by chemical composition is important to optimize metal and oxygen liberation from lunar ore. To this effect, devices capable of separating aluminum bearing minerals from iron-bearing minerals from the lunar regolith simulants have been developed. Twenty-eight different simulants have been used in this study. A dual-belt separator was designed to reduce middling. Para-magnetic minerals were reliably separated using a neodymium N52-magnet-separator system. Effective separation of aluminum-bearing minerals from iron-bearing minerals was greater than …


Thermal Management Of Adsorption-Based Biogas Upgrading Systems Via Incorporation Of Phase-Change Materials, Kyle Newport, Khaled Baamran, Ali A. Rownaghi, Fateme Rezaei Jan 2024

Thermal Management Of Adsorption-Based Biogas Upgrading Systems Via Incorporation Of Phase-Change Materials, Kyle Newport, Khaled Baamran, Ali A. Rownaghi, Fateme Rezaei

Chemical and Biochemical Engineering Faculty Research & Creative Works

Thermal management of adsorption columns is necessary to maintain their effectiveness while reducing the energy requirements of the overall separation process. In this work, we aimed at investigating the suitability of blending adsorbents with phase-change materials (PCMs) to adjust the thermal profile of a biogas upgrading column. A commercially available PCM (Nextek 28D) in quantities of 10, 20, and 30 wt. % was blended with zeolite 13X in two configurations, namely, traditional pellets and 3D-printed monoliths. The use of different structures allows for better analysis of thermal profiles and assessment of the effectiveness of the PCM in a packed bed …


Transitioning To A Lower Global Warming Refrigerant, A Performance Study Of R-513a And Hfc-134a In Commercial Chillers, Hossein Abedsoltan, Mark B. Shiflett Jan 2024

Transitioning To A Lower Global Warming Refrigerant, A Performance Study Of R-513a And Hfc-134a In Commercial Chillers, Hossein Abedsoltan, Mark B. Shiflett

Chemical and Biochemical Engineering Faculty Research & Creative Works

The performance of R-513A and HFC-134a refrigerants is compared in two identical chillers operating at the University of Kansas. R-513A is a more environmentally friendly refrigerant due to its lower global warming potential that can be used as a retrofit replacement for HFC-134a in chillers. This study investigates the performance comparison of transitioning from HFC-134a to R-513A. The chillers have been in operation for two years, and cooling capacity, coefficient of performance, and other operating parameters are compared under similar cooling conditions. Cooling capacities ranged from 100 to 500 kW for both chillers. Overall, the energy consumption and coefficient of …


Fit-For-Purpose Heavy-Duty Fishing Equipment Designed To Safely Retrieve A Damaged Wireline Cable From An Active, Sour Gas Well Located Offshore, M. N. Amri, R. Macaulay, S. Aboelnaga, A. Abouganem, M. Al Dahhan Jan 2024

Fit-For-Purpose Heavy-Duty Fishing Equipment Designed To Safely Retrieve A Damaged Wireline Cable From An Active, Sour Gas Well Located Offshore, M. N. Amri, R. Macaulay, S. Aboelnaga, A. Abouganem, M. Al Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

Wireline operations play a crucial role in the oil and gas industry, facilitating essential tasks like well maintenance, data collection, and intervention. These operations involve deploying substantial downhole tools and large cables into the wellbore, but this endeavor is not without its challenges. Particularly, when a wireline cable breaks downhole, it poses significant risks. Unplanned wireline breakages result in demanding heavy-duty fishing operations when they occur in challenging offshore environments and unfavorable downhole conditions. in this work, strategic planning and execution were applied in a complex e-line cable recovery in a live, sour gas well without the need for well …


Integrated Downhole-Measurement-Enabled Coiled Tubing And Mechanical Wireline Recovery Of E-Line Cable In A Live, Sour Gas Well, C. Villagrana, A. Abouganem, A. M. Afsal, M. Al-Dahhan, J. Delaune, W. R. Tapia, M. Amri Jan 2024

Integrated Downhole-Measurement-Enabled Coiled Tubing And Mechanical Wireline Recovery Of E-Line Cable In A Live, Sour Gas Well, C. Villagrana, A. Abouganem, A. M. Afsal, M. Al-Dahhan, J. Delaune, W. R. Tapia, M. Amri

Chemical and Biochemical Engineering Faculty Research & Creative Works

This study details a complex wire recovery operation in a live well that involved transitioning from coiled tubing (CT) to mechanical wireline (MWL), in both slickline [MA1] or braided line, to retrieve the wire in good condition and later hand it over to an electrical wireline (e-line) unit to spool it onto a drum. the operation was carried out on a live, sour gas well, demanding a unique setup and emphasizing safety. Two successful recovery operations removed a significant amount of e-line left in the well plus the upper section of the e-line bottomhole assembly (BHA) while safely pushing the …


Gan Hemt And Air Core Magnetics Based Power Converters Evaluations At Cryogenic Temperature, Yuqi Wei, Md Maksudul Hossain, H. Alan Mantooth Jan 2024

Gan Hemt And Air Core Magnetics Based Power Converters Evaluations At Cryogenic Temperature, Yuqi Wei, Md Maksudul Hossain, H. Alan Mantooth

Electrical Engineering Faculty Publications and Presentations

Cryogenic power electronics is both advantageous and indispensable in many applications, like deep space probe, military electric vehicle, magnetic resonance imaging etc. Among different semiconductors, the gallium nitride (GaN) high electron mobility transistor (HEMT) is the most promising candidate for cryogenic applications with significant conduction loss and switching loss reductions. Moreover, there is no carrier freeze out effect for the GaN HEMTs, which is applicable in extreme low temperature operating conditions. In this work, the efficiency of GaN HEMTs based power converters with different power levels (from several Watts to several kiloWatts) are evaluated at cryogenic temperature. Three different commercial …


The Impact Of Modern Buildings On Traditional Urban Environments And Urban Identity, Ann S. Ibrahim Jan 2024

The Impact Of Modern Buildings On Traditional Urban Environments And Urban Identity, Ann S. Ibrahim

Al-Esraa University College Journal for Engineering Sciences

Contemporary cities face significant challenges in integrating modern buildings into traditional urban environments while preserving urban identity. This study focuses on the relationship between modern architecture and urban heritage. The research problem revolves around how modern buildings affect urban identity in traditional areas, and whether they can interact positively with the urban context without distorting its traditional character.

The study aims to analyze this impact by examining a range of global examples using architectural indicators such as visual integration, spatial integration, material harmony, urban scale, accessibility, and environmental impact. A three-point scale (weak, partial, excellent) was applied to assess each …


Direct Blue 86 Textile Dye Removal From Aqueous Solution Using Rice Husk-Based Adsorbent, M. Zulbahari M. Zua, Muhammad Raza Ul Mustafa, Mohamed Hasnain Isa, Teh Sabariah Binti Abd Manan, Naimah Ibrahim, Rozeana Hj Md Juani, Wida Susanty Hj Suhaili, Asmaal Muizz Sallehhin Bin Hj Mohammad Sultan, Zuliana Binti Hj Nayan Jan 2024

Direct Blue 86 Textile Dye Removal From Aqueous Solution Using Rice Husk-Based Adsorbent, M. Zulbahari M. Zua, Muhammad Raza Ul Mustafa, Mohamed Hasnain Isa, Teh Sabariah Binti Abd Manan, Naimah Ibrahim, Rozeana Hj Md Juani, Wida Susanty Hj Suhaili, Asmaal Muizz Sallehhin Bin Hj Mohammad Sultan, Zuliana Binti Hj Nayan

ASEAN Journal on Science and Technology for Development

Adsorption by activated carbon is an effective method of dye removal. However, due to high production and regeneration costs of activated carbon, various studies on low-cost adsorbents have been conducted. Agricultural waste such as rice husk (RH) is seen to be a good adsorbent for dye removal. Moreover, rice husk is readily available. In this study, rice husk-based adsorbents were prepared by chemical and thermal treatments. Standard curve (colour vs absorbance) for Direct Blue 86 (DB 86) was prepared to determine the concentration of dye before and after adsorption. The adsorption potential of the adsorbent for textile dye DB 86 …


Economic Profitability Of Sustainable Buildings Industry, Mohanad Ibrahim Altuma, Hanadi Abdulridha Lateef, Ayad Abdulkhaleq Al-Yousuf Jan 2024

Economic Profitability Of Sustainable Buildings Industry, Mohanad Ibrahim Altuma, Hanadi Abdulridha Lateef, Ayad Abdulkhaleq Al-Yousuf

Al-Esraa University College Journal for Engineering Sciences

The increasing global awareness of the Earth's deteriorating condition and the unpredictable effects of climate change has given rise to worldwide phenomena that impact several elements like the economy, agricultural security, water availability, and energy supplies. Buildings contribute significantly to the generation of greenhouse gases, as well as the disposal of pollutants and energy consumption. Therefore, they play a crucial role in addressing environmental issues.

Although sustainable buildings are widely acknowledged as a potential advancement, professionals in the property market still believe that the upfront costs of creating sustainable buildings are significantly higher than those of conventional buildings. This view …


Designing A Visual Control Framework Based On Feature Point Analysis To Guide Robots In Uncharted Areas, Isam Sadiq Rasham Al-Ghadhbawi Jan 2024

Designing A Visual Control Framework Based On Feature Point Analysis To Guide Robots In Uncharted Areas, Isam Sadiq Rasham Al-Ghadhbawi

Al-Esraa University College Journal for Engineering Sciences

Image processing may be made more accurate and efficient with the use of optical processing technologies. In order to make better design judgments early in the package design process, visual packaging art simulation aims to swiftly develop realistic packaging effects. Conventional simulation techniques frequently yield findings that are neither realistic or detailed, and they also take a lot of time and human resources. Optical processing-based machine vision technology can fully utilize computer vision and image processing techniques to simulate package designs accurately and efficiently. This research proposes a foundation for machine vision technologies based on image optical processing. Real package …


Machine-Learning-Assisted Design Of Deep Eutectic Solvents Based On Uncovered Hydrogen Bond Patterns, Usman Lame Abbas, Yuxuan Zhang, Joseph Tapia, Md Selim, Jin Chen, Jian Shi, Qing Shao Jan 2024

Machine-Learning-Assisted Design Of Deep Eutectic Solvents Based On Uncovered Hydrogen Bond Patterns, Usman Lame Abbas, Yuxuan Zhang, Joseph Tapia, Md Selim, Jin Chen, Jian Shi, Qing Shao

Markey Cancer Center Faculty Publications

Non-ionic deep eutectic solvents (DESs) are non-ionic designer solvents with various applications in catalysis, extraction, carbon capture, and pharmaceuticals. However, discovering new DES candidates is challenging due to a lack of efficient tools that accurately predict DES formation. The search for DES relies heavily on intuition or trial-and-error processes, leading to low success rates or missed opportuni- ties. Recognizing that hydrogen bonds (HBs) play a central role in DES formation, we aim to identify HB features that distinguish DES from non-DES systems and use them to develop machine learning (ML) models to discover new DES systems. We first analyze the …


Mathematical Modeling Of Coupled Heat And Mass Transfer In Metal-Hydride Hydrogen Storage Systems, Muhammad Hasnain Jan 2024

Mathematical Modeling Of Coupled Heat And Mass Transfer In Metal-Hydride Hydrogen Storage Systems, Muhammad Hasnain

College of Graduate Studies: Theses & Dissertations

As a promising clean energy carrier hydrogen has recently gained significant interest, but its efficient and safe storage is a major challenge. Compared to the gaseous state and liquid state, metal hydrides (MH) offer a potentially more effective storage approach for hydrogen. However, the main challenge in this approach is the low thermal conductivity of the MH bed that leads to low heat transfer and ultimately to higher charging and discharging times. The purpose of this work is to develop an in-house comprehensive heat and mass transfer model for hydrogen sorption in MH reactors to simulate the dynamic behavior of …


Extrusion-Based Additive Manufacturing Of Magnetic Heat Exchange Structures For Caloric Applications, Vaibhav Sharma Jan 2024

Extrusion-Based Additive Manufacturing Of Magnetic Heat Exchange Structures For Caloric Applications, Vaibhav Sharma

Theses and Dissertations

Currently, the commercial building sector accounts for 18% of total U.S. end-use energy consumption, of which almost a third was from on-site combustion of fossil fuels for space and water heating. Magnetic heat pumping (MHP) technology is an energy-efficient, sustainable, environmentally-friendly alternative to conventional vapor-compression cooling technology. Several MHP designs today are predicted to be highly energy efficient, on condition that suitable working materials can be developed. This materials challenge has proven to be daunting due to issues associated with intricate synthesis/post-processing protocols and complications related to shaping the mostly brittle magnetocaloric alloys into thin-walled channeled regenerator structures to facilitate …


Advanced Synthesis And Rational Design Of Support Structures For Nobel Metal Heterogeneous Catalysis: Towards Enhanced Activity And Continuous Processes, Brian R. Clark Jan 2024

Advanced Synthesis And Rational Design Of Support Structures For Nobel Metal Heterogeneous Catalysis: Towards Enhanced Activity And Continuous Processes, Brian R. Clark

Theses and Dissertations

The field of catalysis has a wide-ranging impact. Our group has identified the constant need for improved catalytic activity in high-impact applications such as hydrosilylation and cross-coupling reactions. For these reactions, precious metal catalysts often exhibit markedly better performance than their counterparts, but they can be a significant process cost that decreases overall economic efficiencies. To address this challenge, we explored support structures that can enhance catalytic activity at low metal loadings and improve precious metal recovery through simple filtration. We found that a platinum on graphene nanoplatelet catalyst (PtGNP) synthesized via strong electrostatic adsorption with microwave irradiation (SEA-MW) exhibits …


Synthesis Of Lithium Nickel Cobalt Manganese Oxide (Ncm) Cathodes For Lithium-Ion Batteries, Jethrine H. Mugumya Jan 2024

Synthesis Of Lithium Nickel Cobalt Manganese Oxide (Ncm) Cathodes For Lithium-Ion Batteries, Jethrine H. Mugumya

Theses and Dissertations

There are various ways to produce lithium nickel manganese cobalt oxide (NCM) based cathodes for lithium-ion batteries, among them; co-precipitation synthesis carried out in tank-based reactors followed by lithiation is commonly employed because of its cost-effectiveness and scalability. Although it is the preferred synthesis method, it has several issues and challenges. Discussed in this dissertation are some of these issues as well as potential solutions. Physical and chemical properties of the co-precipitation product such as yield, particle size, morphology, and tap density, depend on various reaction parameters, which include pH, chelating agents, metal salt concentrations, and stirring speed. In the …


Supported Metal Nanoparticle Synthesis: Precursor Deposition And Agglomeration At Support Surfaces, Edward H. Chandler Jr. Jan 2024

Supported Metal Nanoparticle Synthesis: Precursor Deposition And Agglomeration At Support Surfaces, Edward H. Chandler Jr.

Theses and Dissertations

Catalysis is a critical component of the chemical manufacturing industry. For example, it has been estimated to be essential to more than 90% of the major industrial processes developed during the middle years of the 20th century.1 Heterogeneously supported transition metal catalysts in particular have many benefits such as easy separability from the reaction mixture and high thermal stability. One method of synthesizing these is wet impregnation, wherein a metal solution is brought into contact with an oxide- or carbon-based powder. Given optimal environmental conditions, a metal will adhere to the surface through electrostatic means in a process …


Hydrogen Production From Microbial Electrolysis Cells Powered With Microbial Fuel Cells, Dina Aboelela Jan 2024

Hydrogen Production From Microbial Electrolysis Cells Powered With Microbial Fuel Cells, Dina Aboelela

Biochemical Engineering

No abstract provided.


Synthesis Of Carbon Nanomaterials From Sale Gas Using Nimo/Mgo Catalyst, Ahsan Khan Jan 2024

Synthesis Of Carbon Nanomaterials From Sale Gas Using Nimo/Mgo Catalyst, Ahsan Khan

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study aims to convert greenhouse gases into valuable nanomaterials as a sustainable way to capture and utilize carbon. It examines the synthesis of carbon nanotubes (CNTs) from a methane-ethane mixture (sale gas) with CO₂ added in different reactor setups. A NiMo/MgO catalyst was used to enhance CNT growth. Nickel and molybdenum act as active sites, facilitating to break carbon bonds and supporting CNT formation. The addition of CO₂ promotes dry reforming, which enhances syngas production and influences CNT properties. Factors like gas composition, CO₂ presence, and reactor type affect CNT structure and yield. Extended reaction times improved graphitization, creating …


Change Of Metal Oxidation State At High Temperature, Impact Of Temperature And Reactive Gases, Yegor Nikitin Jan 2024

Change Of Metal Oxidation State At High Temperature, Impact Of Temperature And Reactive Gases, Yegor Nikitin

Dissertations and Theses

The fundamental understanding of gas-solid reactions enables a wide range of applications to be developed and improved. Specifically, the use of metal-based materials is critical to ensuring robust, safe, and long-term operations. For example, in power systems where boilers are used to generate steam for heat or electricity generation the use of stainless metal alloys is critical to allow high quality steam to be produced in a very harsh environment. Alternatively, in catalysis, the use of metal doped heterogeneous catalysts are essential in achieving selectivity and conversion performance for chemical synthesis to emissions abatement. Typically, these metal alloys must withstand …


Nanoparticle Stabilized Interfaces And Their Effect On Foam Stability, Nicole T. Donovan Jan 2024

Nanoparticle Stabilized Interfaces And Their Effect On Foam Stability, Nicole T. Donovan

Dissertations and Theses

No abstract provided.


The Racial Disparities Of The Gamma-Secretase/Notch Pathway And Inhibition In Triple Negative Breast Cancer, Jobin Joseph Jan 2024

The Racial Disparities Of The Gamma-Secretase/Notch Pathway And Inhibition In Triple Negative Breast Cancer, Jobin Joseph

Dissertations and Theses

Triple Negative Breast Cancer (TNBC) continues to be a formidable challenge in oncology, characterized by its aggressive phenotype and limited treatment options. Alarming racial disparities in TNBC outcomes persist, with underrepresented populations experiencing disproportionately higher rates of mortality and poorer prognoses. This master's thesis aims to delve into the molecular intricacies that contribute to these disparities, with a specific focus on gamma secretase activity, a key regulator of cellular processes.

The research methodology encompasses a multi-faceted approach, amalgamating clinical data analysis with extensive in vitro and in vivo experimentation. The study employs cutting-edge molecular profiling techniques and gene expression analysis …


Alkaline Potassium Polyacrylate Electrolytes For Rechargeable Zinc-Manganese Dioxide Batteries, Jungsang Cho Jan 2024

Alkaline Potassium Polyacrylate Electrolytes For Rechargeable Zinc-Manganese Dioxide Batteries, Jungsang Cho

Dissertations and Theses

Zinc (Zn)–manganese dioxide (MnO2) rechargeable batteries have high specific theoretical capacity as well as being environmentally friendly, intrinsically safe and low-cost. Liquid electrolytes, such as potassium hydroxide (KOH), are historically used in these batteries; however, many failure mechanisms of the Zn–MnO2 battery chemistry result from the use of liquid electrolytes, including the formation of electrochemically inactive compounds and shape change of Zn electrodes during charge and discharge cycling. This led to incorporation of an alkaline polymer electrolyte as an alternative to the liquid KOH electrolyte in Zn-MnO2 rechargeable batteries, with the aim of making them non-spillable …


Surface Activity At The Air-Water Interface And Self-Stratification Of Silica Nanoparticles Functionalized With Tri-Methoxy Poly(Ethylene Glycol) Silane, Hyeongoo Jung Jan 2024

Surface Activity At The Air-Water Interface And Self-Stratification Of Silica Nanoparticles Functionalized With Tri-Methoxy Poly(Ethylene Glycol) Silane, Hyeongoo Jung

Dissertations and Theses

Aggregated silica nanoparticles (SNPs) have been functionalized with tri-methoxy poly(ethylene glycol) silane (mPEG silane), end-capped with a methyl group. This functionalization imparts surface activity at the air-water interface due to the hydrophobic nature of the end-capped methyl group. To determine the surface coverage of silane on the particle surface, solution-state 1H-NMR spectroscopy was utilized for characterization, and surface tension measurements were conducted to assess their tension-lowering ability. Solutions containing 10 wt% of the functionalized SNPs reduced the quasi-static surface tension to approximately 53 mN/m, regardless of the amount of reacted mPEG silane. However, the quantification of mPEG silane influenced …


Hydrodynamics Of Drops And Particles Driven By Marangoni And Diffusiophoretic Forces, Subramaniam Chembai Ganesh Jan 2024

Hydrodynamics Of Drops And Particles Driven By Marangoni And Diffusiophoretic Forces, Subramaniam Chembai Ganesh

Dissertations and Theses

This study investigates the hydrodynamics of particles and drops driven by forces generated by an asymmetrical physical and chemical surrounding environment. In the first part, a novel colloidal motor design driven by surface tension forces is proposed, utilizing an active Janus particle encapsulated in an immiscible liquid drop to form a compound drop/particle. Marangoni forces induced by asymmetric solute adsorption at the liquid-liquid interface of the drop propels the compound system. The propulsion speeds of the motor are analyzed for various relative sizes and configurations of the Janus particle and the encapsulating drop and the effects of varying the transport …


Molecular Origins Of Phase Stability In Phase-Change Nano-Emulsions For Thermal Energy Storage By Nmr Spectroscopy, Jungeun Park Jan 2024

Molecular Origins Of Phase Stability In Phase-Change Nano-Emulsions For Thermal Energy Storage By Nmr Spectroscopy, Jungeun Park

Dissertations and Theses

Phase change materials (PCMs) are latent heat storage materials that can store or release thermal energy during phase transitions. Organic PCM nano-emulsions are formed by emulsifying oil in water in the presence of surfactants, enhancing thermal conductivity and pumpability. However, PCMs nano-emulsions can become unstable due to repeated thermal cycling and shear in heat transfer systems.

To better understand the molecular origins of phase instability in PCMs nano-emulsions, liquid-state nuclear magnetic resonance (NMR) measurements were applied to a model PCM nano-emulsion. Quantitative 1H single-pulse NMR measurements established the liquid fraction of oil within nano-emulsions as a function of temperature, …


Understand The Structure-Water-Responsive Relationship By Engineering Silk Materials, Yeojin Jung Jan 2024

Understand The Structure-Water-Responsive Relationship By Engineering Silk Materials, Yeojin Jung

Dissertations and Theses

Water-responsive (WR) materials mechanically swell and shrink in response to changes in relative humidity, and they have demonstrated the capability to exert higher actuation energy than conventional actuators and artificial muscles. As a result, WR materials have recently gained attention as potential high-energy actuating components for engineering applications. Despite the growing interest in this emerging category of WR materials, the fundamental WR mechanism of their significant performance is still not fully understood, limiting the ability to rationally design engineered systems. This dissertation presents three approaches for understanding the water-responsiveness of materials by engineering Bombyx (B.) mori silkworm silk protein. First, …


The Effect Of Nanoconfined Liquid Properties On The Water-Responsive Behavior Of Bacterial Cell Walls, Seungri Kim Jan 2024

The Effect Of Nanoconfined Liquid Properties On The Water-Responsive Behavior Of Bacterial Cell Walls, Seungri Kim

Dissertations and Theses

Water-responsive (WR) materials have the ability to mechanically swell and shrink in response to changes in relative humidity (RH). These WR materials are used by many biological systems to perform essential tasks; for example, pinecones use WR materials to release their seeds in dry environments, and wheat awns open and close to propel seeds into the soil, driven by daily RH changes. The WR actuation of some biomaterials is extremely powerful, for example Bacillus subtilis cell walls display record-high actuation energy and power densities of 72 MJ m-3 and 9.1 MW m-3, surpassing those of all existing …


Assessing The Potential Of Uav-Based Multispectral And Thermal Data To Estimate Soil Water Content Using Geophysical Methods, Yunyi Guan, Katherine R. Grote Jan 2024

Assessing The Potential Of Uav-Based Multispectral And Thermal Data To Estimate Soil Water Content Using Geophysical Methods, Yunyi Guan, Katherine R. Grote

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Knowledge of the soil water content (SWC) is important for many aspects of agriculture and must be monitored to maximize crop yield, efficiently use limited supplies of irrigation water, and ensure optimal nutrient management with minimal environmental impact. Single-location sensors are often used to monitor SWC, but a limited number of point measurements is insufficient to measure SWC across most fields since SWC is typically very heterogeneous. To overcome this difficulty, several researchers have used data acquired from unmanned aerial vehicles (UAVs) to predict the SWC by using machine learning on a limited number of point measurements acquired across a …