Chemical Engineering Commons^™

Improving The Efficiency Of P3ht:Icba Organic Solar Cells By Modifying The Photoactive Solution Preparation Step, Matthew Blaine Samson

Electrical & Computer Engineering Theses & Dissertations

Organic solar cells (OSCs) are a promising alternative to conventional silicon solar cells. These organic devices offer the promise of facile low cost large scale solution based processing on lightweight, flexible, plastic substrates. At the present state of the technology, however, OSCs exhibit relatively low power conversion efficiencies. To improve these efficiencies, new materials are constantly being developed.

One such material is the fullerene indene-C₆₀ bisadduct (ICBA). When implemented in a poly(3-hexylthiophene-2, 5-diyl) (P3HT) : ICBA bulk heterojunction solar cell, these devices exhibit open circuit voltages exceeding 0.8 V, a value much higher than the devices made implementing phenyl-C …

Dynamic Optimization Of A Solar Thermal Energy Storage System Over A 24 Hour Period Using Weather Forecasts, Kody Powell, John Hedengren, Thomas F. Edgar

Faculty Publications

A solar thermal power plant is used as a case study for dynamic heat integration with thermal energy storage. Findings show that thermal energy storage gives the system the ability to make the power dispatchable. Additionally, by solving a 24-hour dynamic optimization problem where the plant temperatures and power output are variable allows the system to capture and harvest a higher percentage of solar energy, with the most benefit occurring on mostly cloudy days. The solar energy captured increases 64% from 4.75 MWh to 7.80 MWh using this scheme. Hybrid plant operation and the ability to bypass the storage tanks …

Model Predictive Control With A Rigorous Model Of A Solid Oxide Fuel Cell, Lee T. Jacobsen, John Hedengren

Faculty Publications

Degradation of Solid Oxide Fuel Cells (SOFCs) can be minimized by maintaining reliability parameters during load changes. These reliability parameters are critical to maintain power generation efficiency over an extended life of the SOFC. For SOFCs to be commercially viable, the life must exceed 20,000 hours for load following applications. This is not yet achieved because transient stresses damage the fuel cell and degrade the performance over time. This study relates the development of a dynamic model for SOFC systems in order to predict optimal manipulated variable moves along a prediction horizon. The model consists of hundreds of states and …

Kinetics Of Tomato Peroxidase Inactivation By Atmospheric Pressure Cold Plasma Based On Dielectric Barrier Discharge, Patrick J. Cullen, Shashi Pankaj, N. Misra

Articles

Atmospheric pressure cold plasma technology is an emerging nonthermal food technology for microbiological decontamination of food and bio-materials. This study demonstrates the applicability of in-package cold plasma technology as a novel means to inactivation of enzymes. The kinetics of inactivation of tomato peroxidase as a model enzyme was studied at 30, 40 and 50kV, for up to 5’ of atmospheric air dielectric barrier discharge plasma treatments. The enzyme activity was found to decrease with both treatment time and voltage, the former variable exhibiting a more pronounced effect. Kinetic models viz. first-order, Weibull and logistic models were fitted to the experimentally …

Decoupling The Stationary Navier-Stokes-Darcy System With The Beavers-Joseph-Saffman Interface Condition, Yong Cao, Yuchuan Chu, Xiaoming He, Mingzhen Wei

Mathematics and Statistics Faculty Research & Creative Works

This paper proposes a domain decomposition method for the coupled stationary Navier-Stokes and Darcy equations with the Beavers-Joseph-Saffman interface condition in order to improve the efficiency of the finite element method. The physical interface conditions are directly utilized to construct the boundary conditions on the interface and then decouple the Navier-Stokes and Darcy equations. Newton iteration will be used to deal with the nonlinear systems. Numerical results are presented to illustrate the features of the proposed method.

Multifunctional Corrosion Inhibition Behavior Of Zn-Al Calcined Layered Double Hydroxides For Steel Rebar In Nacl Solution, Xiao-Juan Zhang, Jing-Jing Wang, Shi-Gang Dong, Chang-Jian Lin

Journal of Electrochemistry

The Zn-Al layered double hydroxides (Zn-Al LDHs) and calcined products (Zn-Al CLDHs) were synthesized successfully under a routine air atmosphere. The results showed that both Zn-Al LDHs and Zn-Al CLDHs had obvious flake structures. The corrosion inhibition of Zn-Al CLDHs for steel rebar in NaCl solution was studied by electrochemical techniques. It was found that the corrosion rate of steel rebar decreased significantly after the steel rebar was treated by Zn-Al CLDHs in NaCl solution for 3 h. It was indicated that Zn-Al CLDHs could absorb Cl^- and release OH^- during their reconstruction process, which provided dual protection …

Preparation And Characterization Of A Novel Composite Electrolyte Ceria-Sulfate For Intermediate Temperature Solid Oxide Fuel Cells, Ze Tong, Yi-Mei Yin, Jie-Wei Yin, Zi-Feng Ma

Journal of Electrochemistry

A novel composite electrolyte SDC-(Li/Na)₂SO₄ was prepared for intermediate temperature solid oxide fuel cells (ITSOFC). The phase structure and cross-sectional morphology were examined by XRD and SEM, respectively, and the ionic conductivity was investigated by AC impedance in a temperature range of 400 ^oC ~ 700 ^oC in air. It was found that the composite electrolyte was composed of two phases: crystal SDC and amorphous (Li/Na)₂SO₄. The conductivity of the composite electrolyte was significantly larger than that of SDC at intermediate temperatures (550 ^oC ~ 700 ^oC) and increased …

Influence Of Electrode Hydrophobicity On Performance Of Alkaline Polymer Electrolyte Fuel Cells, Li-Sheng Tan, Jing Pan, Yao Li, Lin Zhuang, Jun-Tao Lu

Journal of Electrochemistry

In the present work, we study the influence of the electrode hydrophobicity on the performance of alkaline polymer electrolyte fuel cells (APEFCs). QAPS or xQAPS is employed as the membrane and the ionomer, while PTFE is used as a hydrophobic additive in order to adjust the electrode hydrophobicity. We find that enhancing the hydrophobicity of anode can promote the performance of APEFCs, while a moderate hydrophobicity of cathode is required to achieve optimal performance. By using xQAPS as the electrolyte and adding some PTFE in the anode, a peak power density of 132 mW·cm^-2 can be obtained at a …

Electrocatalytic Mechanism And Porous Electrode Mass Transfer Process In Membrane Electrode Assembly For Direct Methanol Fuel Cells, Xin-Dong Wang, Yi-Tuo Wang, Gui-Cheng Liu, Meng Wang, Zhe Tian

Journal of Electrochemistry

Direct methanol fuel cell (DMFC) is considered to be a promising commercial energy conversion device for portable electronics due to its many advantages. In order to improve the performance of DMFC, many companies and research institutes have been launching the deep research and obtaining a lot of conspicuous achievements. In this paper, the electrocatalytic mechanism and porous electrode mass transfer process in membrane electrode assembly (MEA) are analyzed. In addition, combined with the preparation process of MEA, multilayer ordered structures and internal transfer process of the cell, recent progresses of MEA in DMFC are discussed.

Fabrication And Performance Of Lani0.6Fe0.4O3-δCathode Modified By Coating With Gd0.2Ce0.8O2 For Intermediate Temperature Solid Oxide Fuel Cell, Rui-Xuan Ren, Bo Huang, Xin-Jian Zhu, Yi-Xing Hu, Xiao-Yi Ding, Zong-Yao Liu, Ye-Bin Liu

Journal of Electrochemistry

The symmetric cell of LaNi_0.6Fe_0.4O_3-δ/Sc_0.1Zr_0.9O_1.95/LaNi_0.6Fe_0.4O _3-δ was fabricated with screen printing method. A LaNi_0.6Fe_0.4O_3-δ (LNF) cathode was modified by coating with nano-sized gadolinium-doped ceria (GDC, Gd_0.2Ce_0.8O₂) prepared using a simple combustion process within the pores of the cathode. According to the electrochemical impedance spectra (EIS), the polarization resistance of the pure LNF was 0.70 W·cm² at 750 ºC, while 0.13 W·cm² for the 21.3% GDC (by mass)-coated LNF cathode at the …

Developing The Confocal And Fluorescence Microscopy Techniques To Visualize The Eliposomes Inside Of Cells To Treat Cancer, Tara Pandey, Dr. William Pitt

Journal of Undergraduate Research

Cancer is among the leading causes of death in the world. The goal for this project was to visualize a liposome containing perfluorocarbon emulsion an eLiposome, inside of tumor cells using confocal and fluorescence microscopes. A successful study of this project would help to understand the behavior of cancer cells in the presence of drugs during targeted drug delivery for cancer.

The Effect Of Lanthanum On Iron Based Water-Shift Catalysts, Trevor Slade, Dr. Morris Argyle

Journal of Undergraduate Research

The water-gas shift reaction is the reaction where carbon monoxide and water react to form carbon dioxide and hydrogen as shown in equation 1.

Research And Testing Of Pvc Solvent Bonding Methods, David Williams, Dr. William Pitt

Journal of Undergraduate Research

The purpose of this research project was to determine the optimal method to solvent bond polyvinyl chloride (PVC) pieces together. Understanding how to create a strong solvent bond in PVC is important to a related prosthetic leg project that has been performed at BYU. This was completed by bonding flat samples of PVC that were prepared with varying methods.

Charcoal Briquette Manufacturing In The Uros Islands Of Peru, Aaron Harrison, Dr. Vincent Wilding

Journal of Undergraduate Research

The Uros Islands in Peru, also known as the floating islands on Lake Titicaca, are made from reeds by the inhabitants. These reeds serve not only as shelter, but also as the main cooking fuel for nine months of the year. During the other three months the reeds are too wet to burn, so the islanders use propane to prepare their food. Unfortunately, propane can cost more than 50% of their monthly income which is a financial burden to most families on the islands. Additionally, breathing the smoke from these reeds can increase the islanders’ risk of contracting a respiratory …

Waste Treatment For The Uros Islands, Spencer Bowen, Dr. Randy Lewis

Journal of Undergraduate Research

The goal of this project was to design and install one bio-toilet system before the end of May 2011 in cooperation with the inhabitants of the Uros Islands on Lake Titicaca, Peru. The system is composed of two parts: the bio-toilet infrastructure and the treatment of waste. This proposal focuses on waste treatment. The bio-toilet infrastructure was developed in tandem via another project. There are several bio-toilet and waste treatment designs useful for land applications¹; however, the unique challenge of this project was to develop a system that will be able to serve the people living on man-made, …

Updates To A Sequence Of Thermodynamics Experiments For Mechanical Engineering Technology Students, Roger A. Beardsley

All Faculty Scholarship for the School of Graduate Studies and Research

This paper presents an outline of thermodynamics experiments and lab activities that accompany the introductory thermodynamics course for Mechanical Engineering Technology juniors at Central Washington University (CWU) in Ellensburg, Washington. It outlines and describes the current suite of thermodynamics lab activities, comparing the current suite of seven lab activities to a sequence outlined in an ASEE conference paper presented in 1995. Some lab activities in that paper have been replaced, while others have been updated. For example an experiment to measure the Joule-Thomson coefficient has been replaced with a First Law energy balance activity and the former First Law experiment …

Scale-Up Of Bubble Column Reactors: A Review Of Current State-Of-The-Art, Ashfaq Shaikh, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

In Multiphase Flow Reaction Systems, in General, an Extrapolation of Small Diameter Behavior to Larger Ones is Always an Important and Challenging Task. the Critical Issue in Such an Extrapolation Remains to Be Mixing and Hydrodynamic Characteristics. It Needs Reliable Similarity Criteria that Would Result in Similar Mixing and Hydrodynamics and Hence Transport and Performance in Two Different Scales. Numerous Experimental and Computational Studies Have Been Performed to Investigate the Flow Behavior of Bubble Column Reactors for a Proper Design and Scale-Up. Experimental Techniques Vary from Simple Visual Observation to More Advanced Noninvasive Diagnostic Techniques. on Computational Front the Progress …

Conference Program, Engineering Conferences International

BioEnergy IV: Innovations in Biomass Conversion for Heat, Power, Fuels and Chemicals

No abstract provided.

Production Of Renewable Drop-In Fuels And Chemicals From Thermal Conversion Of Non-Edible Lipids, David Bressler, Paolo Mussone

BioEnergy IV: Innovations in Biomass Conversion for Heat, Power, Fuels and Chemicals

No abstract provided.

Ionic Liquid Based Extraction Of Lipids From Micro-Algae, Lars Rehmann

BioEnergy IV: Innovations in Biomass Conversion for Heat, Power, Fuels and Chemicals

No abstract provided.