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Full-Text Articles in Engineering

Advanced Manufacturing And Nanotechnology For Non-Noble Metal-Based Oxygen Evolution Electrocatalysts, Bowei Zhang Jan 2019

Advanced Manufacturing And Nanotechnology For Non-Noble Metal-Based Oxygen Evolution Electrocatalysts, Bowei Zhang

Graduate Theses and Dissertations

The oxygen evolution reaction (OER) plays vital roles in electrochemical energy conversion and storage applications, including water-splitting systems, fuel cells, metal-air batteries, and CO2 reduction devices, but the development of highly active and robust OER catalysts based on non-noble metals by simple methods is challenging. In this dissertation, three major strategies are proposed for developing advanced OER electrocatalysts at low cost by simple and versatile methods. In the first work, a bimetallic Ni-Fe-P nanosheet arrays were designed and fabricated as a pre-catalyst to catalyzing super high OER current densities under alkaline and neutral media. To catalyze a 10 mA/cm2 ...


An Agent-Based Approach To Modeling Sustainable Sociotechnical Systems, Anuj Mittal Jan 2019

An Agent-Based Approach To Modeling Sustainable Sociotechnical Systems, Anuj Mittal

Graduate Theses and Dissertations

A gradual evolution in the food and energy sectors towards decentralized decision-making is requiring participant organizations to consider new approaches to the design of policies and processes. Increasing consumer preference for food sourced from small-scale regional farmers has led to changing logistics requirements. Similarly, as consumers have become conscious of the impacts of climate change on the environment, they have begun to adopt renewable sources to meet their energy needs. Moreover, the emergence of new technologies has enabled consumers to generate their own energy. Such shifts in decision-making power to consumers necessitates the consideration of their perspectives and preferences when ...


Supported Perovskite-Type Oxides: Establishing A Foundation For Co2 Conversion Through Reverse Water-Gas Shift Chemical Looping, Bryan J. Hare Mar 2018

Supported Perovskite-Type Oxides: Establishing A Foundation For Co2 Conversion Through Reverse Water-Gas Shift Chemical Looping, Bryan J. Hare

Graduate Theses and Dissertations

Perovskite-type oxides show irrefutable potential for feasible thermochemical solar-driven CO2 conversion. These materials exhibit the exact characteristics required by the low temperature reverse water-gas shift chemical looping process. These properties include structural endurance and high oxygen redox capacity, which results in the formation of numerous oxygen vacancies, or active sites for CO2 conversion. A major drawback is the decrease in oxygen self-diffusion with increasing perovskite particle size. In this study, the La0.75Sr0.25FeO3 (LSF) perovskite oxide was combined with various supports including popular redox materials CeO2 and ZrO2 along with ...


The Effects Of Scale On Granular Mixing In A Double Screw Pyrolyzer, Breanna L. Marmur Jan 2015

The Effects Of Scale On Granular Mixing In A Double Screw Pyrolyzer, Breanna L. Marmur

Graduate Theses and Dissertations

Granular mixing processes are important to many industries including the pharmaceutical, agricultural, and biotechnology industries. These processes often require both a high degree of homogeneity and a high degree of customizability. As granular mixing processes are so widely employed, a thorough understanding of the mixing dynamics is necessary to understand and control the resulting products. Research into granular mixing processes has been, thus far, largely focused on laboratory scale mixers with simple geometries, while actual industrial processes often require large mixers with complex geometries. Moreover, granular mixing processes are often very sensitive to changes in operating conditions and any solutions ...


Economic Decision Making Of Renewable Power Producers Under Uncertainty, Chenlu Lou Jan 2014

Economic Decision Making Of Renewable Power Producers Under Uncertainty, Chenlu Lou

Graduate Theses and Dissertations

The recent booming development of renewable power generation and government subsidies are constantly under scrutiny and various opinions exist regarding whether subsidies should be continued or not. Motivated by the controversies and debates, this dissertation attempted to address the investment decision making problem under uncertainties in the renewable power industry from the perspective of an individual power producer.

Given that independent power producers still dominate the renewable power production and that majority of their output are sold through long-term power purchase agreements, this study focused on two types of uncertainties that could represent most of their kinds: the operations & maintenance ...


Economic Analysis For Transmission Operation And Planning, Qun Zhou Jan 2011

Economic Analysis For Transmission Operation And Planning, Qun Zhou

Graduate Theses and Dissertations

Restructuring of the electric power industry has caused dramatic changes in the use of transmission system. The increasing congestion conditions as well as the necessity of integrating renewable energy introduce new challenges and uncertainties to transmission operation and planning. Accurate short-term congestion forecasting facilitates market traders in bidding and trading activities. Cost sharing and recovery issue is a major impediment for long-term transmission investment to integrate renewable energy.

In this research, a new short-term forecasting algorithm is proposed for predicting congestion, LMPs, and other power system variables based on the concept of system patterns. The advantage of this algorithm relative ...


Generation Portfolio Optimization Under Wind Production Tax Credit And Renewable Portfolio Standard, Chenlu Lou Jan 2011

Generation Portfolio Optimization Under Wind Production Tax Credit And Renewable Portfolio Standard, Chenlu Lou

Graduate Theses and Dissertations

In this thesis we construct and analyze a mean-variance utility maximization model for a risk-averse electric power generation company who wishes to determine the optimal levels of capacity and production from a single conventional fuel source and wind energy subject to the state Renewable Portfolio Standard (RPS). We assume the conventional fuel price and the federal wind power Production Tax Credit (PTC) level are random variables. This study is motivated by the highly stochastic nature of the PTC level and the existing competing claims for the impact of the RPS on the renewable energy development. Throughout our model we show ...


Designing Effective And Efficient Incentive Policies For Renewable In Generation Expansion Planning, Ying Zhou Jan 2010

Designing Effective And Efficient Incentive Policies For Renewable In Generation Expansion Planning, Ying Zhou

Graduate Theses and Dissertations

We present a bilevel optimization approach to designing effective and efficient incentive policies for promoting renewable energy. The effectiveness of an incentive policy is its capability to achieve a goal that would not be achievable without it. Renewable

portfolio standard is used in this thesis as the policy goal. The efficiency of an incentive policy is measured by the amount of intervention, such as taxes collected and subsidies

paid, to achieve the policy goal. We obtain the most effective and efficient incentive policies in the context of generation expansion planning, in which a planner makes investment decisions to serve project ...


Extension Of Electrical Engineering To Bioengineering Topics: Magnetic Fermentation And Microfluidic Nematode Assays, Alex John Deutmeyer Jan 2009

Extension Of Electrical Engineering To Bioengineering Topics: Magnetic Fermentation And Microfluidic Nematode Assays, Alex John Deutmeyer

Graduate Theses and Dissertations

The Department of Electrical and Computer Engineering (ECpE) at Iowa State University added bioengineering to the department's list of strategic research areas in 2006. In an effort to foster a bioengineering center of excellence within the department and to promote multidisciplinary research, two bioengineering research projects were performed: magnetic fermentation and microfluidic nematode assay development. The background of these research topics, the work completed for each, and their future prospects are discussed in this thesis.

Fuel ethanol produced through fermentation has recently received attention during the search for eco-friendly, renewable energy sources. Previous research has been completed to observe ...


Experimental Improvements On A Tornado-Type Wind Turbine (Ttwt) System, Matt Hawkins Jan 2009

Experimental Improvements On A Tornado-Type Wind Turbine (Ttwt) System, Matt Hawkins

Graduate Theses and Dissertations

The Tornado-Type Wind Turbine (TTWT) is a novel design for a wind energy generator utilizing the properties of vortex flow. The TTWT diverts freestream wind into a spiral-shaped chamber, creating a vortex with a low-pressure region in the center. This pressure drop is used to draw ambient air captured below through to the vortex chamber. Energy is extracted with a turbine at this interface. A successful TTWT design will extract more energy at a given wind speed than a traditional horizontal-axis wind turbine (HAWT). The TTWT will be quieter, easier to maintain, and more robust with respect to wind gusts ...