Engineering Commons^™

Functional Material Systems For Stimuli-Responsive Interference Coloration, Milad Momtaz

Theses and Dissertations

Part I: Responsive Interference Coloration (RIC) Systems for High-Performance Humidity Sensing

High-humidity conditions (85−100% relative humidity) have a variety of effects on many aspects of our daily lives. In spite of significant progress in the development of structural coloration-based humidity sensors, enhancing the sensitivity and visual humidity resolution of these sensors at high-humidity environment remains a big challenge. In this work, high-performance colorimetric humidity sensors based on environment-friendly konjac glucomannan (KGM) are introduced. These sensors are fabricated via thin-film interference and prepared using a simple, affordable, and scalable method. An effective approach is shown for markedly improving the sensitivity and …

Synthesis And Characterization Of Polyether-Ether Ketone Supported Tppa-1 Covalent Organic Framework Membrane For Organic Solvent Nanofiltration, Rahul Sampat Khandge

Theses and Dissertations

There is a lot of potential for energy-efficient separation in membranes made up of covalent organic frameworks (COF). It has been reported that COFs are able to separate dyes, salts, bacteria, and nanoparticles based on size-selective transport through ordered pore structure. They have recently emerged as promising membranes for separations involving organic liquids. In the last decade, organic solvent nanofiltration (OSN) has received a lot of attention since it is an energy- and waste-efficient method for separating mixtures down to the molecular level. Although the number of OSN publications has increased in recent years, there is a need to search …

Study Of Lead Sulfate Growth Kinetics In Lead Acid Sli Batteries, Dustin Wenninger

Theses and Dissertations

The importance of a safe and reliable way to both store and use energy, has led to a significant amount of research in the field of secondary battery development and refinement. The thesis herein explores a new application of a mature technology that has proven viable for internal combustion engines (ICE). Though the technology has proven viable for the start, lighting, and ignition, of conventional ICEs, the development of such advanced battery systems to meet the energy demands of Hybrid Electric Vehicles (HEV) is not without challenge. Lead acid SLI secondary batteries have demonstrated high recyclability, low self-discharge, good performance …

Silica-Based Materials For Water Treatment Applications: Adsorption And Supported Noble Metal-Based Catalysis, Xiaopeng Min

Theses and Dissertations

Various contaminants have been widely detected in aquatic systems due to both natural and anthropogenic activities, such as conventional and emerging organic pollutants (e.g., nitroarenes, per- and poly-fluoroalkyl substances (PFAS)), and toxic oxyanions (e.g., chlorate, selenate). The presence of these contaminants may pose negative effects on both human health and water systems. Therefore, it is of great desire to develop novel materials and technologies to treat these waterborne pollutants.Catalytic treatment using noble metal (e.g., Pd)-based catalysts has emerged as a promising method for reduction of waterborne contaminants. Silica-based supports may enhance the reactivity and sustainability of Pd-based catalysts by improving …

Understanding Heterostructure Chemiresistive Gas Sensing At Room Temperature, Yale Wang

Theses and Dissertations

Chemiresistive sensors are the most widely investigated gas sensors due to their ease in fabrication, cost-effectiveness, simplicity of operation, and offer advances in miniaturization. Up to date, typical and well-researched resistive-type sensing materials include semiconductor metal oxides, noble metals, carbon-based nanomaterials (e.g., graphene and carbon nanotubes), and conducting polymers. Gas sensors based on a single material were found difficult to meet the practical requirements for multi-sensing properties, including sensitivity, selectivity, speed of response/recovery, stability, limit of detection, and room temperature operation. Rational design through a combination of chemically or electronically dissimilar nanomaterials is an effective route to enhancing gas sensing …

Applying A Statistical Approach To Develop A Sustainable Technology For Capturing Phosphorous From An Agricultural Tile Drainage System Using By-Product Phosphorous Sorbing Materials (Psm), Amir Kordijazi

Theses and Dissertations

Due to nutrient pollution, agriculture is one of the major sources of pollution in water bodies. Every time it rains, fertilizers, pesticides, and animal waste wash nutrients and pathogens—such as bacteria and viruses—into waterways. As rainfall increases due to climate change, the water problem will worsen. One of the nutrients that extensively contributes to the degradation of water quality is phosphorous (P). In this research, the performance of electric arc furnace (EAF) steel slag was investigated as a P sorbing materials (PSM) according to the conditions present in a P removal structure designed for treating water discharge from an agricultural …

Performance Of Centrifugally Cast Austenitic Alumina-Forming Alloys In Coking And Decoking Environments, Lizeth Ortiz

Theses and Dissertations

Ethylene, the most-produced building block in the petrochemical industry, is produced using thermal cracking operations where reactor materials are exposed to high temperature aggressive environments that limit their life expectancy. These atmospheres degrade the reactor's material due to exposure to high temperatures, to carbon, to sulfur, and to other compounds, affecting negatively its process operations and therefore, its economics.

One of the most undesirable phenomena in ethylene thermal cracking operations is coking, where a carbon layer is deposited on the walls of the furnace tubes causing a reduction in the process efficiency as well as degradation of the alloy. This …