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Wright State University

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Full-Text Articles in Physics

Epistemic Games Analysis Of Common Exam Questions Across Course Formats, Jonathan V. Mahadeo, Adrienne L. Traxler, Eric Brewe Jul 2013

Epistemic Games Analysis Of Common Exam Questions Across Course Formats, Jonathan V. Mahadeo, Adrienne L. Traxler, Eric Brewe

Physics Faculty Publications

This study investigates differences in problem-solving performance between three different introductory physics course formats at Florida International University. The course formats--lecture+laboratory (LL), inquiry-based (IQB), and lecture+laboratory+recitation (LLR)--all incorporated two Advanced Placement (AP) questions into their final exams. Students' written responses were evaluated via an AP scoring rubric, and during this scoring, we observed marked differences in solution behavior between the three course formats. To further investigate these differences, we used the framework of epistemic games to analyze student responses. To apply this framework to written work, an epistemic game rubric was created. Application of this rubric ...


Nano-Objects And Nanochemistry By Selective Atom Diffusion At Advanced Semiconductor Surfaces & Interfaces, Patrick Soukiassian Jun 2013

Nano-Objects And Nanochemistry By Selective Atom Diffusion At Advanced Semiconductor Surfaces & Interfaces, Patrick Soukiassian

Special Session 5: Carbon and Oxide Based Nanostructured Materials (2013)

No abstract provided.


Characterisation Of Core@Shell Nanoparticles Using Advanced Electron Microscopy, Andrew Wheatley Jun 2013

Characterisation Of Core@Shell Nanoparticles Using Advanced Electron Microscopy, Andrew Wheatley

Special Session 5: Carbon and Oxide Based Nanostructured Materials (2013)

No abstract provided.


Heating Mechanisms Of Magnetic Nanoparticles In Hyperthermia Treatment, Anna Lukawska, Gregory Kozlowski Jun 2013

Heating Mechanisms Of Magnetic Nanoparticles In Hyperthermia Treatment, Anna Lukawska, Gregory Kozlowski

Special Session 5: Carbon and Oxide Based Nanostructured Materials (2013)

No abstract provided.


Photo-Electro-Magnetic Or Photo-Thermo-Magneto-Electric Effects In Graphene?, Marian Nowak, Gregory Kozlowski, B. Solecka, M. Jesionek Jun 2013

Photo-Electro-Magnetic Or Photo-Thermo-Magneto-Electric Effects In Graphene?, Marian Nowak, Gregory Kozlowski, B. Solecka, M. Jesionek

Special Session 5: Carbon and Oxide Based Nanostructured Materials (2013)

No abstract provided.


Cluster Approach To The Electronic Properties Modeling Of Nanocrystal Structures, Malgorzata Makowska-Janusik, Nathalie Herlin-Boime, Johann Boucle, Abdel Hadi Kassiba Jun 2013

Cluster Approach To The Electronic Properties Modeling Of Nanocrystal Structures, Malgorzata Makowska-Janusik, Nathalie Herlin-Boime, Johann Boucle, Abdel Hadi Kassiba

Special Session 5: Carbon and Oxide Based Nanostructured Materials (2013)

No abstract provided.


On The Catalyst-Free Fabrication Of Carbon Nanotubes And Graphene, Mark Ruemmeli Jun 2013

On The Catalyst-Free Fabrication Of Carbon Nanotubes And Graphene, Mark Ruemmeli

Special Session 5: Carbon and Oxide Based Nanostructured Materials (2013)

No abstract provided.


Extending Positive Class Results Across Multiple Instructors And Multiple Classes Of Modeling Instruction, Eric Brewe, Adrienne L. Traxler, Jorge De La Garza, Laird H. Kramer Jan 2013

Extending Positive Class Results Across Multiple Instructors And Multiple Classes Of Modeling Instruction, Eric Brewe, Adrienne L. Traxler, Jorge De La Garza, Laird H. Kramer

Physics Faculty Publications

We report on a multiyear study of student attitudes measured with the Colorado Learning Attitudes about Science Survey in calculus-based introductory physics taught with the Modeling Instruction curriculum. We find that five of six instructors and eight of nine sections using Modeling Instruction showed significantly improved attitudes from pre- to postcourse. Cohen’s d effect sizes range from 0.08 to 0.95 for individual instructors. The average effect was d = 0.45, with a 95% confidence interval of (0.26–0.64). These results build on previously published results showing positive shifts in attitudes from Modeling Instruction classes. We ...


Compensation In Al-Doped Zno By Al-Related Acceptor Complexes: Synchrotron X-Ray Absorption Spectroscopy And Theory, Jiraroj T-Thienprasert, S. Rujirawat, W. Klysubun, J. N. Duenow, T. J. Coutts, S. B. Zhang, David C. Look, Sukit Limpijumnong Jan 2013

Compensation In Al-Doped Zno By Al-Related Acceptor Complexes: Synchrotron X-Ray Absorption Spectroscopy And Theory, Jiraroj T-Thienprasert, S. Rujirawat, W. Klysubun, J. N. Duenow, T. J. Coutts, S. B. Zhang, David C. Look, Sukit Limpijumnong

Physics Faculty Publications

The synchrotron x-ray absorption near edge structures (XANES) technique was used in conjunction with first-principles calculations to characterize Al-doped ZnO films. Standard characterizations revealed that the amount of carrier concentration and mobility depend on the growth conditions, i.e. H2 (or  O2)/Ar gas ratio and Al concentration. First-principles calculations showed that Al energetically prefers to substitute on the Zn site, forming a donor AlZn, over being an interstitial (Ali). The measured Al K-edge XANES spectra are in good agreement with the simulated spectra of AlZn, indicating that the majority of Al atoms are substituting ...


Saturation-Dependence Of Dispersion In Porous Media, B. Ghanbarian-Alavijeh, Thomas E. Skinner, Allen Hunt Dec 2012

Saturation-Dependence Of Dispersion In Porous Media, B. Ghanbarian-Alavijeh, Thomas E. Skinner, Allen Hunt

Physics Faculty Publications

In this study, we develop a saturation-dependent treatment of dispersion in porous media using concepts from critical path analysis, cluster statistics of percolation, and fractal scaling of percolation clusters. We calculate spatial solute distributions as a function of time and calculate arrival time distributions as a function of system size. Our previous results correctly predict the range of observed dispersivity values over ten orders of magnitude in experimental length scale, but that theory contains no explicit dependence on porosity or relative saturation. This omission complicates comparisons with experimental results for dispersion, which are often conducted at saturation less than 1 ...


Growth Of Graphene Architectures On Sic, John J. Boeckl, Weijie Lu, William C. Mitchel, Kurt G. Eyink, Howard Smith, Larry Grazulis, Gerry Landis, Said Elhamri Jun 2012

Growth Of Graphene Architectures On Sic, John J. Boeckl, Weijie Lu, William C. Mitchel, Kurt G. Eyink, Howard Smith, Larry Grazulis, Gerry Landis, Said Elhamri

Special Session 5: Carbon and Oxide Based Nanostructured Materials (2012)

No abstract provided.


Properties Of Sbsi@Cnts And Sbsi Nanowires, Marian Nowak, Krzysztof Koziol, Gregory Kozlowski, Krystian Mistewicz, Marcin Jesionek Jun 2012

Properties Of Sbsi@Cnts And Sbsi Nanowires, Marian Nowak, Krzysztof Koziol, Gregory Kozlowski, Krystian Mistewicz, Marcin Jesionek

Special Session 5: Carbon and Oxide Based Nanostructured Materials (2012)

No abstract provided.


In-Situ Engineering Of Graphene With Electrons, Mark Ruemmeli Jun 2012

In-Situ Engineering Of Graphene With Electrons, Mark Ruemmeli

Special Session 5: Carbon and Oxide Based Nanostructured Materials (2012)

No abstract provided.


Magnetic Nanoparticles In Hyperthermia Treatment, Gregory Kozlowski Jun 2012

Magnetic Nanoparticles In Hyperthermia Treatment, Gregory Kozlowski

Special Session 5: Carbon and Oxide Based Nanostructured Materials (2012)

No abstract provided.


New Routes To Copper Nanocatalysts For Fine Chemical Synthesis, Pavel Abdulkin, Yanina Moglie, Faysal Benaskar, Volker Engels, Jan Meuldijk, Volker Hessel, Emiel J. M. Hensen, Miguel Yus, Jaap C. Schouten, Francisco Alonso, Andrew E. H. Wheatley Jun 2012

New Routes To Copper Nanocatalysts For Fine Chemical Synthesis, Pavel Abdulkin, Yanina Moglie, Faysal Benaskar, Volker Engels, Jan Meuldijk, Volker Hessel, Emiel J. M. Hensen, Miguel Yus, Jaap C. Schouten, Francisco Alonso, Andrew E. H. Wheatley

Special Session 5: Carbon and Oxide Based Nanostructured Materials (2012)

No abstract provided.


Ac Magnetic Heating Of Superparamagnetic Fe And Co Nanoparticles, Anna Lukawska, Zafrullah Jagoo, Gregory Kozlowski, Zafer Turgut, Hiroyuki Kosai, Alexander Sheets, Tyler Bixel, Andrew Wheatley, Pavel Abdulkin, Benjamin Knappett, Thomas Houlding, Volkan Degirmenci Jun 2012

Ac Magnetic Heating Of Superparamagnetic Fe And Co Nanoparticles, Anna Lukawska, Zafrullah Jagoo, Gregory Kozlowski, Zafer Turgut, Hiroyuki Kosai, Alexander Sheets, Tyler Bixel, Andrew Wheatley, Pavel Abdulkin, Benjamin Knappett, Thomas Houlding, Volkan Degirmenci

Special Session 5: Carbon and Oxide Based Nanostructured Materials (2012)

No abstract provided.


Extraordinary Optical Transmission And Extinction In A Terahertz Wire-Grid Polarizer, J. S. Cetnar, J. R. Middendorf, Elliott R. Brown Jun 2012

Extraordinary Optical Transmission And Extinction In A Terahertz Wire-Grid Polarizer, J. S. Cetnar, J. R. Middendorf, Elliott R. Brown

Physics Faculty Publications

A THz wire grid polarizer is simulated and demonstrated consisting of 40-μm periodic aluminum strips mounted on a polycarbonate substrate with a variable metal-to-gap ratio. Full-wave numerical simulations were performed from 100 GHz to 550 GHz predicting that the transmission in perpendicular (parallel) polarization is much higher (lower) than that predicted by geometric optics, leading to a very high extinction ratio of ∼60 dB between 100 and 550 GHz when the gaps become very small (<5 >μm). This behavior is confirmed qualitatively in experiments between 100 and 530 GHz where extinction ratios exceeding 40 dB are achieved. These ...


A New Model For Mixing By Double-Diffusive Convection (Semi-Convection): I. The Conditions For Layer Formation, G. M. Mirouh, P. Garaud, S. Stellmach, Adrienne L. Traxler, T. S. Wood Jan 2012

A New Model For Mixing By Double-Diffusive Convection (Semi-Convection): I. The Conditions For Layer Formation, G. M. Mirouh, P. Garaud, S. Stellmach, Adrienne L. Traxler, T. S. Wood

Physics Faculty Publications

The process referred to as "semi-convection" in astrophysics and "double-diffusive convection in the diffusive regime" in Earth and planetary sciences occurs in stellar and planetary interiors in regions which are stable according to the Ledoux criterion but unstable according to the Schwarzschild criterion. In this series of papers, we analyze the results of an extensive suite of three-dimensional (3D) numerical simulations of the process, and ultimately propose a new 1D prescription for heat and compositional transport in this regime which can be used in stellar or planetary structure and evolution models. In a preliminary study of the phenomenon, Rosenblum et ...


Stable Highly Conductive Zno Via Reduction Of Zn Vacancies, David C. Look, Timothy C. Droubay, Scott A. Chambers Jan 2012

Stable Highly Conductive Zno Via Reduction Of Zn Vacancies, David C. Look, Timothy C. Droubay, Scott A. Chambers

Physics Faculty Publications

Growth of Ga-doped ZnO by pulsed laser deposition at 200 °C in an ambient of Ar and H2produces a resistivity of 1.5 × 10−4 Ω-cm, stable to 500 °C. The resistivity can be further reduced to 1.2 × 10−4 Ω-cm by annealing on Zn foil, which reduces the compensating Zn-vacancy acceptor concentration NA to 5 × 1019 cm−3, only 3% of the Ga-donor concentration ND of 1.6 × 1021 cm−3, with ND and NA determined from a degenerate mobility theory. The plasmon-resonance wavelength is only 1060 nm, further bridging ...


A Mems Photoacoustic Detector Of Terahertz Radiation For Chemical Sensing, Nathan E. Glauvitz, S. Blazevic, Ronald A. Coutu Jr., Michael N. Kistler, Ivan Medvedev, Douglas T. Petkie Jan 2012

A Mems Photoacoustic Detector Of Terahertz Radiation For Chemical Sensing, Nathan E. Glauvitz, S. Blazevic, Ronald A. Coutu Jr., Michael N. Kistler, Ivan Medvedev, Douglas T. Petkie

Physics Faculty Publications

A piezoelectric Microelectromechanical system (MEMS) cantilever pressure sensor was designed, modeled, fabricated, and tested for sensing the photoacoustic response of gases to terahertz (THz) radiation. The sensing layers were comprised of three thin films; a lead zirconate titanate (PZT) piezoelectric layer sandwiched between two metal contact layers. The sensor materials were deposited on the silicon device layer of a silicon-on-insulator (SOI) wafer, which formed the physical structure of the cantilever. To release the cantilever, a hole was etched through the backside of the wafer and the buried oxide was removed with hydrofluoric acid. Devices were then tested in a custom ...


Model For Triggering Of Non-Volcanic Tremor By Earthquakes, Naum I. Gershenzon, Gust Bambakidis Jan 2012

Model For Triggering Of Non-Volcanic Tremor By Earthquakes, Naum I. Gershenzon, Gust Bambakidis

Physics Faculty Publications

There is evidence of tremor triggering by seismic waves emanating from distant large earthquakes. The frequency content of both triggered and ambient tremor are largely identical, suggesting that this property does not depend directly on the nature of the source. We show here that the model of plate dynamics developed earlier by us is an appropriate tool for describing tremor triggering. In the framework of this model, tremor is an internal response of a fault to a failure triggered by external disturbances. The model predicts generation of radiation in a frequency range defined by the fault parameters. Thus, although the ...


Broadband 180 Degree Universal Rotation Pulses For Nmr Spectroscopy Designed By Optimal Control, Thomas E. Skinner, Naum I. Gershenzon, Manoj Nimbalkar, Wolfgang Bermel, Burkhard Luy, Steffen J. Glaser Jan 2012

Broadband 180 Degree Universal Rotation Pulses For Nmr Spectroscopy Designed By Optimal Control, Thomas E. Skinner, Naum I. Gershenzon, Manoj Nimbalkar, Wolfgang Bermel, Burkhard Luy, Steffen J. Glaser

Physics Faculty Publications

Broadband inversion pulses that rotate all magnetization components 180 degrees about a given fixed axis are necessary for refocusing and mixing in high-resolution NMR spectroscopy. The relative merits of various methodologies for generating pulses suitable for broadband refocusing are considered. The de novo design of 180 degree universal rotation pulses using optimal control can provide improved performance compared to schemes which construct refocusing pulses as composites of existing pulses. The advantages of broadband universal rotation by optimized pulses (BURBOP) are most evident for pulse design that includes tolerance to RF inhomogeneity or miscalibration. We present new modifications of the optimal ...


Transition From Static To Dynamic Macroscopic Friction In The Framework Of The Frenkel-Kontorova Model, Naum I. Gershenzon, Gust Bambakidis Nov 2011

Transition From Static To Dynamic Macroscopic Friction In The Framework Of The Frenkel-Kontorova Model, Naum I. Gershenzon, Gust Bambakidis

Physics Faculty Publications

A new generation of experiments on dry macroscopic friction has revealed that the transition from static to dynamic friction is essentially a spatially and temporally non-uniform process, initiated by a rupture-like detachment front. We show the suitability of the Frenkel-Kontorova model for describing this transition. The model predicts the existence of two types of detachment fronts, explaining both the variability and abrupt change of velocity observed in experiments. The quantitative relation obtained between the velocity of the detachment front and the ratio of shear to normal stress is consistent with experiments. The model provides a functional dependence between slip velocity ...


Characterization Of Metameterial Devices Using Terahertz Time-Domain Spectroscopy, Hannah R. Jones, Satya Ganti, Jason A. Deibel, Ronald A. Coutu Jr. Oct 2011

Characterization Of Metameterial Devices Using Terahertz Time-Domain Spectroscopy, Hannah R. Jones, Satya Ganti, Jason A. Deibel, Ronald A. Coutu Jr.

Physics Faculty Publications

No abstract provided.


Terahertz Spectroscopic Reflection And Scattering Measurements Of Aligned Cnt Arrays As A Function Of Carbon Nanotube Length, Satya Ganti, Lindsay Owens, Stanley Smith Iv, Jason A. Deibel Oct 2011

Terahertz Spectroscopic Reflection And Scattering Measurements Of Aligned Cnt Arrays As A Function Of Carbon Nanotube Length, Satya Ganti, Lindsay Owens, Stanley Smith Iv, Jason A. Deibel

Physics Faculty Publications

No abstract provided.


Crucible Coating Analysis By Thz Spectroscopy, Ryan Shaver, Hannah R. Jones, Jason A. Deibel Oct 2011

Crucible Coating Analysis By Thz Spectroscopy, Ryan Shaver, Hannah R. Jones, Jason A. Deibel

Physics Faculty Publications

No abstract provided.


Self-Compensation In Semiconductors: The Zn Vacancy In Ga-Doped Zno, David C. Look, K. D. Leedy, L. Vines, B. G. Svensson, A. Zubiaga, F. Tuomisto, Daniel R. Doutt, L. J. Brillson Sep 2011

Self-Compensation In Semiconductors: The Zn Vacancy In Ga-Doped Zno, David C. Look, K. D. Leedy, L. Vines, B. G. Svensson, A. Zubiaga, F. Tuomisto, Daniel R. Doutt, L. J. Brillson

Physics Faculty Publications

Self-compensation, the tendency of a crystal to lower its energy by forming point defects to counter the effects of a dopant, is here quantitatively proven. Based on a new theoretical formalism and several different experimental techniques, we demonstrate that the addition of 1.4 × 1021-cm−3 Ga donors in ZnO causes the lattice to form 1.7 × 1020-cm−3 Zn-vacancy acceptors. The calculated VZn formation energy of 0.2 eV is consistent with predictions from density functional theory. Our formalism is of general validity and can be used to investigate self-compensation in any degenerate semiconductor ...


Thermal Annealing Effect On Spin Coherence In Zno Single Crystals, Z. Yang, David C. Look, H. M. Zhou, W. V. Kawakami, R. K. Kawakami, P. K. L. Yu, J. L. Liu Jul 2011

Thermal Annealing Effect On Spin Coherence In Zno Single Crystals, Z. Yang, David C. Look, H. M. Zhou, W. V. Kawakami, R. K. Kawakami, P. K. L. Yu, J. L. Liu

Physics Faculty Publications

The spin coherence time (T2*) in ZnO single crystals at 8.5 K decreases significantly from ∼11.2 ns to ∼2.3 ns after annealing at 500 °C, as indicated by time-resolved Kerr-rotation pump-probe magneto-optical spectroscopy. The annealing-induced spin coherence degradation in ZnO arises neither from crystallinity degradation during the annealing process, as confirmed by x-ray rocking curves; nor from reflection variations of the probe laser beam induced by surface roughness changes during the annealing process, as confirmed by atomic force microscopy. Temperature-dependent Hall-effect studies indicate that decreased mobility and increased shallow-donor concentration in the annealing-induced surface conducting layer ...


High Ammonia Yield Using Magnetic Induction Method, Noorhana Yahya Jun 2011

High Ammonia Yield Using Magnetic Induction Method, Noorhana Yahya

Special Session 5: Carbon and Oxide Based Nanostructured Materials (2011)

No abstract provided.


Nano-Based Optical Chemical Sensors, Aleksandra Lobnik Jun 2011

Nano-Based Optical Chemical Sensors, Aleksandra Lobnik

Special Session 5: Carbon and Oxide Based Nanostructured Materials (2011)

No abstract provided.