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2015

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Articles 20101 - 20130 of 22283

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Exploring The Application Of Meta-Raps For Scheduling Flow Shops With Blocking, Mohammad Sadaqa Jan 2015

Exploring The Application Of Meta-Raps For Scheduling Flow Shops With Blocking, Mohammad Sadaqa

Graduate Research Theses & Dissertations

A single machine includes loading and unloading areas for each job processed in it in a way that loading and unloading operations could be performed while the machine is running. This leads to minimizing the completion of the jobs with lowest machine idle time. This design requires a special kind of scheduling technique for jobs to ensure the accomplishment of those objectives if the processing, loading, and unloading times are varying. The machine is modeled as a flow shop with blocking constraint. This research focuses on finding a solution to schedule this special case of flow shop as a flow …

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Can Motivation Facilitate L1 English-L2 Spanish Learners' Acquisition Of L2 Phonology?, Marion Rebecca Gibney-Desmaison Jan 2015

Can Motivation Facilitate L1 English-L2 Spanish Learners' Acquisition Of L2 Phonology?, Marion Rebecca Gibney-Desmaison

Graduate Research Theses & Dissertations

Phonology is one of the most difficult aspects of a second language (L2) for learners to fully acquire, yet pronunciation of sounds that are similar across languages is rarely addressed in L2 Spanish classes. If two sounds are very similar between two languages, they are actually more difficult for learners to differentiate. How does learner motivation affect the acquisition of L2 sounds that are similar to the first language (L1)?;The present study investigates the connection between student motivation toward learning a foreign language and student L2 accent production. Ten L1 English-L2 Spanish learners from two different (fourth- and fifth-semester) Spanish …

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Cfd Analysis Of Blood Flow Through Stenosed Arteries, Narmada Surigala Jan 2015

Cfd Analysis Of Blood Flow Through Stenosed Arteries, Narmada Surigala

Graduate Research Theses & Dissertations

The pathological complications of atherosclerosis, namely heart disease and stroke, remain the leading cause of mortality in the world. Cardiovascular illness is highly prevalent among the American population. One manifesto of cardiovascular disease is Peripheral Artery Disease (PAD) which is caused by atherosclerosis in the arteries. Atherosclerosis is a vascular disease that reduces arterial lumen size through plaque deposition and arterial wall thickening. The flow patterns in the arteries are highly modulating along with the cardiac cycle and a strong function of the waveform created by the heartbeat. In this study, a computational simulation model is developed to analyze blood …

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Combinatorial Interpretations Of Continued Fractions With Multiple Limit Points, Herman Schaumburg Jan 2015

Combinatorial Interpretations Of Continued Fractions With Multiple Limit Points, Herman Schaumburg

Graduate Research Theses & Dissertations

This dissertation establishes an Euler-Minding type theorem for the continued fraction with numerator elements --1 and denominator elements 1 + bi, where bi is a sequence of indeterminants. This theorem is employed to derive new partition identities from Ramanujan's well-known q-continued fraction which diverges to three limit points. Continued fractions that diverge to two limits are also considered: alternating partitions studied by Andrews are shown to occur in this context, and a new proof of a result of Alladi is given.

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Computation Of Contact Points Between Wheel And Rail Surfaces, Chao Pan Jan 2015

Computation Of Contact Points Between Wheel And Rail Surfaces, Chao Pan

Graduate Research Theses & Dissertations

Wheel and rail contact point analysis is a fundamental and critical problem in dynamic simulation of railroad vehicle. The objective of this study is to develop an efficient method to compute the contact points between rails and a wheelset. This is achieved by locating the common normal and then reducing the chord distance along it to zero. In this process, the structure of the governing equations is exploited to achieve higher computational efficiency. The method is adapted to two, three, and four simultaneous contact points.

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Conceptual Metaphors In Ayn Rand's "Philosophy: Who Needs It", Ilya Startsev Jan 2015

Conceptual Metaphors In Ayn Rand's "Philosophy: Who Needs It", Ilya Startsev

Graduate Research Theses & Dissertations

This thesis analyzes metaphorical constructions in Ayn Rand's speech and essay "Philosophy: Who Needs It." Metaphors as condensed analogies and Lakovian conceptual metaphors play an important role in constructing Objectivist worldview and reframing the audience's views. Rand identifies philosophy by using three metaphors: Mind Is Computer, Life Is A Battle, and the novel Philosophy Is War. The frames derived from the metaphorical constructions are intercompared through some Objectivist non-fiction to show a consistent worldview. Rand's rhetoric is also known to influence movement conservatives, and this connection is found through conceptual metaphors Capitalism Is God's Will and the Strict Father morality.

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An Exploration Of Elementary Teachers' Self-Efficacy Beliefs About Teaching Mathematics Among Teachers With Advanced Degrees, Kelly J. Talaga Jan 2015

An Exploration Of Elementary Teachers' Self-Efficacy Beliefs About Teaching Mathematics Among Teachers With Advanced Degrees, Kelly J. Talaga

Graduate Research Theses & Dissertations

The present study sought to explore the sources of elementary teachers' mathematics teaching self-efficacy beliefs. Through the use of Seidman's in-depth interviewing protocol, four teachers with master's degrees in reading education and four teachers with master's degrees in mathematics education described their perceived sources of self-efficacy, including their experiences as students and teachers. The first research question addressed the three areas of mathematics teaching self-efficacy: content knowledge, instructional methods, and assessment techniques. The second research question examined whether there were differences in the perceived sources of self-efficacy based on the participants' degrees. Data were analyzed using descriptive coding and focused …

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Investigations And Applications Of Field- And Photo-Emitted Electron Beams From A Radio Frequency Gun, Sriharsha Panuganti Jan 2015

Investigations And Applications Of Field- And Photo-Emitted Electron Beams From A Radio Frequency Gun, Sriharsha Panuganti

Graduate Research Theses & Dissertations

Production of quality electron bunches using efficient ways of generation is a crucial aspect of accelerator technology. Radio frequency electron guns are widely used to generate and rapidly accelerate electron beams to relativistic energies. In the current work, we primarily study the charge generation processes of photoemission and field emission inside an RF gun installed at Fermilab's High Brightness Electron Source Laboratory (HBESL). Specifically, we study and characterize second-order nonlinear photoemission from a Cesium Telluride (Cs2Te) semiconductor photocathode, and field emission from carbon based cathodes including diamond field emission array (DFEA) and carbon nanotube (CNT) cathodes located in the RF …

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Scientific Discovery And The Poetic Response, Joey Crundwell Jan 2015

Scientific Discovery And The Poetic Response, Joey Crundwell

Graduate Research Theses & Dissertations

This thesis has two primary goals: the first is to explore the relationship between scientific discovery and poetry by surveying poetry from the last four hundred years and revealing instances where the two worlds have met. With the rise of modern science, profound scientific discovery has had a history of affecting how poets see themselves and the world in which they live, though an argument exists that claims that contemporary poets have ceased responding to scientific discovery on a personal level and are instead simply adopting the vocabulary and imagery of science. The second goal of this thesis is to …

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Sensorless Speed Estimation Of An Ac Induction Motor By Using An Artificial Neural Network Approach, Abdulelah Ali Alkhoraif Jan 2015

Sensorless Speed Estimation Of An Ac Induction Motor By Using An Artificial Neural Network Approach, Abdulelah Ali Alkhoraif

Graduate Research Theses & Dissertations

Sensorless speed detection of an induction motor is an attractive area for researchers to enhance the reliability of the system and to reduce the cost of the components. This paper presents a simple method of estimating a rotational speed by utilizing an artificial neural network (ANN) that would be fed by a set of stator current frequencies that contain some saliency harmonics. This approach allows operators to detect the speed in induction motors such an approach also provides reliability, low cost, and simplicity. First, the proposed method is based on converting the stator current signals to the frequency domain and …

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Teaching Argument : How Prepared Are Middle School Teachers To Teach Argument?, Victoria D. Albon Jan 2015

Teaching Argument : How Prepared Are Middle School Teachers To Teach Argument?, Victoria D. Albon

Graduate Research Theses & Dissertations

This study examines how prepared middle school teachers are to teach argument in the classroom. Specifically, the review focuses on what teachers report that they know about how to teach argument in their classroom, and how they are aligning argument instruction with Common Core State Standards. This study also focuses on what approaches teachers use to instruct argument writing, and what their instruction reveals about what they know about principled practice. A review of the literature highlights the work of Stephen Toulmin and the alignment of his conception of argument patterns with Common Core State Standards. It also focuses on …

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Solar Stand-Alone System With Storage And Dc Bus Control, Sandeep Reddy Lethakula Jan 2015

Solar Stand-Alone System With Storage And Dc Bus Control, Sandeep Reddy Lethakula

Graduate Research Theses & Dissertations

Now-a-days people are busy in finding the replacement for fossil fuels, because fossil fuels are at a stage of extinction. As the demand for energy requirement is high, the fossil fuels alone cannot meet the energy requirements. Some kind of clean, efficient, cheap and self-sustainable energy sources should be used, few of them are solar, wind, geothermal and hydro-power. As of now, it's a global mission to use the renewable energy sources, which can control the global warming and many other ecological imbalances. Many governments are encouraging and supporting for new researches in this field.;Among all energy sources, solar energy …

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Quantifying The Spatial Variability Of Fractures And Fracture Network Properties, John Robert Hanke Jan 2015

Quantifying The Spatial Variability Of Fractures And Fracture Network Properties, John Robert Hanke

Graduate Research Theses & Dissertations

Fracture networks can have a significant impact on the performance of subsurface reservoirs, and therefore have a wide variety of industrial applications (e.g., oil and gas, economic ore deposits, hydrogeology, environmental science). Collectively, these industries make multi-trillion dollar decisions based on information gathered from geological models. As a result, these industries are faced with the ongoing risk that unreliable models lead to costly mistakes.;The reliability of all rock fracture models is coupled with the spatial variability (e.g., spatial heterogeneity and anisotropy) of fracture network characteristics. This study provides a foundation for developing a new generation of mechanical and stochastic fracture …

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Tracking The Gap : A Closer Look At Student- And School-Level Characteristics, Aundrea R.J. Lane Jan 2015

Tracking The Gap : A Closer Look At Student- And School-Level Characteristics, Aundrea R.J. Lane

Graduate Research Theses & Dissertations

The goals of this study were to evaluate achievement gaps between varying sub-group populations (i.e., ethnicity, gender, and socio-economic status) as well as estimate which student-level and or school-level characteristics account for variance in reading growth over time. This longitudinal study followed a cohort of 2,077 students (1st -- 5th grade) nested within one school district's 21 elementary schools. The participant's early literacy (Letter Sound Fluency), reading-curriculum based measure (R-CBM), and Illinois Standards Achievement Test (ISAT) scores were analyzed utilizing univariate and multivariate analyses of variance (ANOVAs and MANOVAs). School-level characteristics were entered into hierarchical linear models to evaluate variance …

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Tri-Axis Modified Helmholtz Coil System For Magnetometer Characterization And Calibration, Kristen Marie Allen Jan 2015

Tri-Axis Modified Helmholtz Coil System For Magnetometer Characterization And Calibration, Kristen Marie Allen

Graduate Research Theses & Dissertations

In this thesis, the design of a tri-axis magnetometer characterization and calibration system is realized through the use of three pairs of modified Helmholtz Coils. These three pairs of coils, with each pair separated by their shared diameter and placed along the three orthogonal directions, will, when supplied with a current, produce a known magnetic field in the surrounding environment that will serve to excite a magnetometer, a sensor that serves to measure magnetic fields, placed at the center of the system. Commercially available magnetometers, the HMC5843 and HMC5883L, will be employed to test the functionality of the coil system …

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The Mirage Of Curriculum Decentralization : A Case Study Of Local Stakeholders' Involvement In School-Based Curriculum Development (Sbcd) Policy Implementation In Indonesia, Muhamad Ali Akrom Jan 2015

The Mirage Of Curriculum Decentralization : A Case Study Of Local Stakeholders' Involvement In School-Based Curriculum Development (Sbcd) Policy Implementation In Indonesia, Muhamad Ali Akrom

Graduate Research Theses & Dissertations

This study examined local stakeholders' involvement in the School-Based Curriculum Development (SBCD) policy implementation in five elementary schools in a city in the southeastern region of Indonesia. An interpretive qualitative case study design was applied. Participants in the study consisted of principals, teachers, parents/School Committee members, and key officials from the local education authority. Four data collection strategies were employed in this study: semi-structured interviews, focus groups, observations, and document analysis. The data obtained were analyzed qualitatively using a constant comparative method. Nvivo 10 was also used to facilitate the analysis process.;Findings of the study indicated that the local stakeholders …

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Factors That Affect The Development Of Writing Competence In Fifth-Grade Students, Ellen D. Weinstein-Blackman Jan 2015

Factors That Affect The Development Of Writing Competence In Fifth-Grade Students, Ellen D. Weinstein-Blackman

Graduate Research Theses & Dissertations

This dissertation explores writing instruction in fifth-grade classrooms, focusing on the attitudes and behaviors of student writers of differing abilities and their teachers' activities during written language instruction. Assessment of student writing, classroom observations, and interviews with students and teachers showed that above-average, average, and struggling writers have different perceptions about the skills necessary to master the writing process and that their views differed from those of their teachers. While teachers attempted to model composing, editing, revising, and publishing for their students, it was challenging for fifth-grade students to integrate these skills to create high-quality writing products. Writers of different …

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First Clear The Way, Then Press Forward : Implementation Intentions And Job Search Behaviors, Christopher Joseph Budnick Jan 2015

First Clear The Way, Then Press Forward : Implementation Intentions And Job Search Behaviors, Christopher Joseph Budnick

Graduate Research Theses & Dissertations

Boredom is an aversive internal state that increases task-irrelevant thinking, decreases task-directed concentration, and hinders task performance. Job seekers often struggle with boredom while completing job search tasks. Implementation intentions -- goal-directed action plans -- might prove an effective means of coping with boredom during task completion. Prior research has incorporated various forms of implementation intentions but has not yet examined which forms are most effective during the job search. Using a laboratory experiment, I randomly assigned 151 undergraduate student participants to one of four conditions: (1) a superordinate goal only, (2) an implementation intention to reduce distraction, (3) an …

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Flexible Modeling Of Competing Risks And Cure Rate In Survival Analysis, Qi Jiang Jan 2015

Flexible Modeling Of Competing Risks And Cure Rate In Survival Analysis, Qi Jiang

Graduate Research Theses & Dissertations

Advancement in medical sciences has produced therapies with curative potential for some diseases regarded as terminal in the past. Yet, patients may simultaneously be subject to multiple diseases, not all of which can be cured. When there is only disease in the context and that disease has a cure possibility, a rich class of cure models can be built by taking into consideration the underlying mechanisms leading to cure and relapse. We propose a class of flexible cure models that accounts for uncertainties in such mechanisms. Our proposed model includes many existing cure models as special cases and can be …

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Fusion Rings With Degrees 1 And 4, Tyler Lewis Mitchell Jan 2015

Fusion Rings With Degrees 1 And 4, Tyler Lewis Mitchell

Graduate Research Theses & Dissertations

Fusion rings are a class of table algebras that generalize group rings with basis the group and character rings of a finite group with basis the irreducible characters. Examples are the Grothendieck rings of fusion categories, algebraic structures that are related to conformal field theory. When considering the character ring of a group as a fusion ring, the usual degree of a character coincides with the value assigned by the degree map. Hence classifying fusion rings based on the degree set is a generalization of classifying groups based on the degrees of the irreducible characters. The main theorem classifies real …

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Gifted Learners' Motivational Outcomes In Cluster Versus Ability-Grouped Reading Instruction : An Ex-Post Facto Study, Julie Esparza Jan 2015

Gifted Learners' Motivational Outcomes In Cluster Versus Ability-Grouped Reading Instruction : An Ex-Post Facto Study, Julie Esparza

Graduate Research Theses & Dissertations

This post hoc study focused on gifted programming in language arts for students in fourth through eighth grades in one large (n=12,229) diverse school district. One group of gifted students experienced cluster grouping, while the other group of gifted students experienced ability grouping for language arts instruction. The study examined whether motivational processes reported by gifted students differed by gender, race/ethnicity, and socioeconomic level. The study also investigated whether gifted students who were ability grouped for reading instruction differed in self-efficacy, achievement goal orientation, achievement, and challenge seeking in language arts when compared to gifted students who were cluster grouped. …

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Illinois' Performance Evaluation Reform Act (Pera) Examined Within The Context Of The Federal Government's Expanding Role In Public Education, Hillary A. Nasso Jan 2015

Illinois' Performance Evaluation Reform Act (Pera) Examined Within The Context Of The Federal Government's Expanding Role In Public Education, Hillary A. Nasso

Graduate Research Theses & Dissertations

This study examines the ever-expanding role of the federal government's involvement in the American public education system to put the 2010 Illinois Performance Evaluation Act (PERA) into context. Understanding the history of federal education policy and the federal government's involvement in public education (historically the domain of the states) helps illuminate the current situation in Illinois. The 2010 Performance Evaluation Reform Act (PERA) changed the method of evaluating the performance of public school teachers. This alteration incorporated student academic growth data into the evaluation calculation. This is the first time Illinois teacher performance evaluations will be based in part on …

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Image Quality Measures In Proton Computed Tomography, Saroj Rai Jan 2015

Image Quality Measures In Proton Computed Tomography, Saroj Rai

Graduate Research Theses & Dissertations

Proton therapy is an external beam radiotherapy that uses proton beam as ionizing radiation to treat localized tumor cells within the human body. The calculated proton beam range is used to locate and damage the DNA of cancerous tissue, thus, leading to cell death. Due to the Bragg peak characteristic of protons, the range of proton beam in matter can be calculated accordingly which offers greater degree of conformal dose delivery than conventional X-ray beam therapy. Currently, the treatment planning of proton therapy is based on the X-ray computed tomography (CT) scans of the patient anatomy. The images reconstructed from …

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Liquid Level Measurement Using Non-Contact Radar, Kaushik Bukka Jan 2015

Liquid Level Measurement Using Non-Contact Radar, Kaushik Bukka

Graduate Research Theses & Dissertations

The present research is related to liquid level measurement using a non-contact radar. For this purpose we employ a Mono-Doppler transceiver whose function is to transmit and receive electromagnetic waves. The primary objective of the research is to estimate the height of water level in a tank and to build an efficient measuring device.;"Mono-Doppler transceiver operates as a pulse radar device. It emits pulses of microwaves in a duration of nanoseconds. For this reason the transceiver has high repetition rate. Within very short duration, a received signal is observed, the time delay of the received signal is used to evaluate …

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Mathematics Beliefs And Teaching Practices Of Preschool Teachers, Kristine L. Black Jan 2015

Mathematics Beliefs And Teaching Practices Of Preschool Teachers, Kristine L. Black

Graduate Research Theses & Dissertations

The purpose of this study was to examine preschool teachers' beliefs about teaching mathematics to preschool students and how teachers help preschool students acquire math skills and knowledge in the classroom. The research was conducted in two parts: focus groups and classroom observations. The focus groups occurred over two sessions. The sessions focused on building a sense of teachers' beliefs about which mathematics skills should be taught to preschool children and which teaching strategies, if any, were currently used to teach the skills. The researcher recorded the focus groups and transcribed them. Coding was done to identify themes. The second …

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Meta-Raps For A Bi-Objective Unrelated Parallel Machine Scheduling Problem, Nixon Dcoutho Jan 2015

Meta-Raps For A Bi-Objective Unrelated Parallel Machine Scheduling Problem, Nixon Dcoutho

Graduate Research Theses & Dissertations

This thesis discusses the capability and effectiveness of a meta-heuristic for Randomized Priority Search to solve multi-objective problems. The multi-objective problem of unrelated parallel machine scheduling is considered in the thesis. The two objectives to minimize are total weighted tardiness and total weighted completion time. Two approaches are suggested to solve the problem. The first approach uses an existing construction rule in the literature named Apparent Tardiness Cost-bi heuristic, which is used as the basis for the meta-heuristic construction phase in Meta-RaPS to generate non-dominated solutions. The computational results obtained are promising when results of the meta-heuristic approach proposed are …

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Middle School Girls And One Stem Ost Program, Andrea Holba Jan 2015

Middle School Girls And One Stem Ost Program, Andrea Holba

Graduate Research Theses & Dissertations

This dissertation examines motivation in middle school girls involved in one STEM OST program. Specifically, motivation is examined through four distinct components. These components are attention, relevance, confidence, and satisfaction. Although these components are unique, they cumulatively create a holistic picture of motivation in program design. The middle school girl participants were observed at program workshops and personal interviews. Exploring program design elements through this lens of motivation was a qualitative effort to both understand how participants respond to design elements, and what might encourage future participation in STEM activities.

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Mosfet Parameter Extraction And Spice Modeling, Sai Subhash Sripada Jan 2015

Mosfet Parameter Extraction And Spice Modeling, Sai Subhash Sripada

Graduate Research Theses & Dissertations

This paper proposes a simple extraction technique which can be used to extract device parameters of any power MOSFET easily. It only requires the use of transfer and output characteristic graphs to extract threshold voltage and transconductance and a few formulas to extract the parasitic capacitances of the power device. The extraction technique is presented in an easy to understand step by step procedure. The parameters extracted using this process are used to develop a spice model. Transient analysis is done for the extracted model and the resistive switching performance is compared with the datasheet in order to prove the …

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Numerical And Experimental Study Of Bauschinger Effect On Aa5182 Sheets, Abhinav Talla Jan 2015

Numerical And Experimental Study Of Bauschinger Effect On Aa5182 Sheets, Abhinav Talla

Graduate Research Theses & Dissertations

For stamping process, most of the sheet metal elements undergo a complicated deformation process that may comprise a sequence of stretching, bending, unbending and reverse bending processes. For this kind of deformation, the Bauschinger effect must be considered in order to calculate the internal stress within the parts before springback. To understand the Bauschinger effect phenomenon on AA5182-O temper, a fixture for cyclic double-shear test has been designed and manufactured. This test can induce cyclic shear loading on the specimen during experiment. LS-Dyna has also been used to simulate this experiment.

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Plasma Treated Mesoporous Tio2 Thin Films For Energy Storage Applications, Allen D. Reed Jan 2015

Plasma Treated Mesoporous Tio2 Thin Films For Energy Storage Applications, Allen D. Reed

Theses and Dissertations--Chemistry

Mesoporous TiO2 films treated with N2/argon plasma or H2 plasma were studied for use in photoelectrochemical water splitting and electrochemical supercapacitors, respectively. Cubic-ordered mesoporous thin films were prepared by a templated sol-gel method. UV-Vis absorbance spectra indicated that nitrogen plasma treatment significantly reduced the band gap of the TiO2. XPS analysis showed that nitrogen atoms are incorporated into substitutional sites, rather than interstitial. Photocatalytic activity of nitrogen-doped TiO2 films was evaluated by chronoamperometry and linear sweep voltammetry. Compared to pristine TiO2, plasma-treated films showed remarkable photocurrent enhancement (up to 240 times) …

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