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High Pressure Synchrotron Xrd, Nfs, And Nrixs Studies Of Fesb2, Melanie Alden White Aug 2020

High Pressure Synchrotron Xrd, Nfs, And Nrixs Studies Of Fesb2, Melanie Alden White

UNLV Theses, Dissertations, Professional Papers, and Capstones

This work combines high pressure synchrotron X-ray diffraction (XRD), nuclear forward scattering (NFS), and nuclear resonant inelastic X-ray scattering (NRIXS) experiments on iron diantimonide (FeSb2), a promising thermoelectric material. NRIXS uses the interaction between excited nuclear and lattice states to directly measure the phonon density of states (PDOS) for samples containing certain Mössbauer isotopes. For our experiments, we synthesized FeSb2 enriched with the isotope 57Fe and measured the partial PDOS for 57Fe sites in the FeSb2 lattice. NFS, also known as synchrotron Mössbauer spectroscopy, is a sister technique to NRIXS that studies the hyperfine structure of the excited Mössbauer nuclei. …

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Probing The Intergalactic Turbulence With Fast Radio Bursts, Siyao Xu, Bing Zhang Jul 2020

Probing The Intergalactic Turbulence With Fast Radio Bursts, Siyao Xu, Bing Zhang

Physics & Astronomy Faculty Research

The turbulence in the diffuse intergalactic medium (IGM) plays an important role in various astrophysical processes across cosmic time, but it is very challenging to constrain its statistical properties both observationally and numerically. Via the statistical analysis of turbulence along different sight lines toward a population of fast radio bursts (FRBs), we demonstrate that FRBs provide a unique tool to probe the intergalactic turbulence. We measure the structure function (SF) of dispersion measures (DMs) of FRBs to study the multiscale electron density fluctuations induced by the intergalactic turbulence. The SF has a large amplitude and a Kolmogorov power-law scaling with …

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Constraining Ancient Magmatic Evolution On Mars Using Crystal Chemistry Of Detrital Igneous Minerals In The Sedimentary Bradbury Group, Gale Crater, Mars, V. Payré, K. L. Siebach, R. Dasgupta, Arya Udry, E. B. Rampe, S. M. Morrison Jul 2020

Constraining Ancient Magmatic Evolution On Mars Using Crystal Chemistry Of Detrital Igneous Minerals In The Sedimentary Bradbury Group, Gale Crater, Mars, V. Payré, K. L. Siebach, R. Dasgupta, Arya Udry, E. B. Rampe, S. M. Morrison

Geoscience Faculty Research

Understanding magmatic processes is critical to understanding Mars as a system, but Curiosity's investigation of dominantly sedimentary rocks has made it difficult to constrain igneous processes. Igneous classification of float rocks is challenging because of the following: (1) the possibility that they have been affected by sedimentary processes or weathering, and (2) grain size heterogeneity in the observed rock textures makes the small‐scale compositions measured by rover instruments unreliable for bulk classification. We avoid these ambiguities by using detrital igneous mineral chemistry to constrain models of magmatic processes in the source region for the fluvio‐deltaic Bradbury group. Mineral chemistry is …

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Utility Of Inflammatory Markers To Predict Adverse Outcome In Acute Pancreatitis: A Retrospective Study In A Single Academic Center, Mohamad Mubder, Banreet Dhindsa, Danny Nguyen, Syed Saghir, Chad Cross, Ranjit Makar, Gordon Ohning Jul 2020

Utility Of Inflammatory Markers To Predict Adverse Outcome In Acute Pancreatitis: A Retrospective Study In A Single Academic Center, Mohamad Mubder, Banreet Dhindsa, Danny Nguyen, Syed Saghir, Chad Cross, Ranjit Makar, Gordon Ohning

School of Medicine Faculty Research

Background/Aim: Acute pancreatitis (AP) is a commonly encountered emergency where early identification of complicated cases is important. Inflammatory markers like lymphocyte to monocyte ratio (LMR) and neutrophil to lymphocyte ratio (NLR) are simple and readily available markers. In this study, we evaluated the utility of these markers in the early identification of patients with complicated AP. Patients and Methods: All patients with a diagnosis of AP admitted to the University Medical Center in Las Vegas/Nevada between August 2015 and September 2018 were identified using ICD-10 codes. Medical records were reviewed retrospectively. Epidemiological measures and their associated confidence intervals were calculated …

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Health Lifestyles And The Transition To Adulthood, Elizabeth Lawrence, Stefanie Mollborn, Joshua Goode, Fred Pampel Jul 2020

Health Lifestyles And The Transition To Adulthood, Elizabeth Lawrence, Stefanie Mollborn, Joshua Goode, Fred Pampel

Sociology Faculty Research

Prior research has shown the theoretical importance and empirical feasibility of health lifestyles but has not examined their patterns over the life course or their dynamic associations with socioeconomic status (SES) and adult roles. The authors develop and apply a life-course approach to understanding individuals’ health lifestyles across the transition to adulthood, using U.S. data from the National Longitudinal Study of Adolescent to Adult Health (n = 6,863). The results show that ascribed SES is associated with adolescent health lifestyles, and those health lifestyles are associated with later health lifestyles. The results also demonstrate the developmental specificity of health lifestyles. …

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Chemist Table: A Tool For Designing Or Modifying Instruction For A Systems Thinking Approach In Chemistry Education, Sarah York, Marykay Orgill Jul 2020

Chemist Table: A Tool For Designing Or Modifying Instruction For A Systems Thinking Approach In Chemistry Education, Sarah York, Marykay Orgill

Chemistry and Biochemistry Faculty Research

Recently, there have been calls to integrate systems thinking approaches into chemistry education in order to strengthen students’ conceptual understanding, build their problem-solving capabilities, and prepare them to make informed, ethical decisions about globally relevant issues, such as sustainability. Unfortunately, implementation of systems thinking approaches in chemistry classrooms currently poses challenges. Exemplar systems thinking materials with a STEM focus are limited, particularly at the tertiary level. Moreover, the science education community has yet to agree upon a systems thinking definition or develop a comprehensive list of systems thinking skills that students should develop. Thus, a current priority for the advancement …

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Gain Scores, Ancova, And Propensity Matching Procedures For Evaluating Treatments In Education, Daniel B. Wright Jul 2020

Gain Scores, Ancova, And Propensity Matching Procedures For Evaluating Treatments In Education, Daniel B. Wright

Educational Psychology, Leadership, and Higher Education Faculty Research

Researchers have several options available to analyze data from interventions when participants have not been randomly allocated into conditions. Among these are the gain score, ANCOVA, and propensity matching procedures. Each of these attempts to account for pre-treatment differences among the conditions, but they do so differently. These procedures are reviewed and methods for estimating them in R are shown. The choice of which of these procedures to use can be diffcult. Different situations are shown where they perform differently. The primary conclusion of this paper is that models should be hypothesized for how the data may arise, data simulated …

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Preservation Of Latest Cretaceous (Maastrichtian) - Paleocene Frogs (Eorubeta Nevadensis) Of The Sheep Pass Formation Of East-Central Nevada And Implications For Paleogeography Of The Nevadaplano, Joshua W. Bonde, Peter A. Druschke, Richard P. Hilton, Amy C. Henrici, Stephen M. Rowland Jul 2020

Preservation Of Latest Cretaceous (Maastrichtian) - Paleocene Frogs (Eorubeta Nevadensis) Of The Sheep Pass Formation Of East-Central Nevada And Implications For Paleogeography Of The Nevadaplano, Joshua W. Bonde, Peter A. Druschke, Richard P. Hilton, Amy C. Henrici, Stephen M. Rowland

Geoscience Faculty Research

Here we report on exceptional preservation of remains of the frog Eorubeta nevadensis in deposits of the Sheep Pass Formation, ranging from Late Cretaceous to Eocene, in the south Egan Range, Nevada. This formation represents a lacustrine basin within the Sevier retroarc hinterland. The formation is subdivided into six members (A–F); of interest here are members B and C. The base of member B is ?uppermost Cretaceous-Paleocene, while member C is Paleocene. Member B frogs are preserved in three taphonomic modes. Mode 1 frogs are nearly complete and accumulated under attritional processes, with frogs settling on microbial mats, as evidenced …

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Doctoral Program Design Based On Technology-Based Situated Learning And Mentoring: A Comparison Of Part-Time And Full-Time Doctoral Students, Shaoan Zhang, Chengcheng Li, Mark Carroll, P. G. Schrader Jun 2020

Doctoral Program Design Based On Technology-Based Situated Learning And Mentoring: A Comparison Of Part-Time And Full-Time Doctoral Students, Shaoan Zhang, Chengcheng Li, Mark Carroll, P. G. Schrader

Teaching and Learning Faculty Research

Aim/Purpose: Most programs are designed with full-time doctoral students’ characteristics and needs in mind; few programs consider the unique needs of part-time doctoral students, including time restrictions, experiences during the program, identity development, and different professional aspirations. The purpose of this study was to evaluate the potential differences between part-time and full-time doctoral students in their scholarly development, and how technology may serve as a communication and organization tool for individual and program support. Background: Built on the application of communities of practice, information and communication technology, and situated learning theory, this study sought to evaluate the potential differences among …

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Design Aspects, Energy Consumption Evaluation, And Offset For Drinking Water Treatment Operation, Saria Bukhary, Jacimaria Batista, Sajjad Ahmad Jun 2020

Design Aspects, Energy Consumption Evaluation, And Offset For Drinking Water Treatment Operation, Saria Bukhary, Jacimaria Batista, Sajjad Ahmad

Civil and Environmental Engineering and Construction Faculty Research

Drinking water treatment, wastewater treatment, and water distribution are energy-intensive processes. The goal of this study was to design the unit processes of an existing drinking water treatment plant (DWTP), evaluate the associated energy consumption, and then offset it using solar photovoltaics (PVs) to reduce carbon emissions. The selected DWTP, situated in the southwestern United States, utilizes coagulation, flocculation, sedimentation, filtration, and chlorination to treat 3.94 m3 of local river water per second. Based on the energy consumption determined for each unit process (validated using the plant’s data) and the plant’s available landholding, the DWTP was sized for solar PV …

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Improving Trust In Research: Supporting Claims With Evidence, Daniel B. Wright Jun 2020

Improving Trust In Research: Supporting Claims With Evidence, Daniel B. Wright

Educational Psychology, Leadership, and Higher Education Faculty Research

Trust in science is important, and Open Education Studies aims to publish trusted research. Two issues are addressed here: access to the data on which the research is based and how these data are analyzed. Some guidelines from other entities are discussed. As a new journal our guidelines should be influenced by the opinions of readers and authors, and as such we welcome discussion of how to ensure trust in the research OES publishes.

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Great Basin Paleoclimate And Aridity Linked To Artic Warming And Tropical Pacific Sea Surface Temperature, Matthew S. Lachniet, Yemane Asmerom, Victor Polyak, Rhawn Denniston Jun 2020

Great Basin Paleoclimate And Aridity Linked To Artic Warming And Tropical Pacific Sea Surface Temperature, Matthew S. Lachniet, Yemane Asmerom, Victor Polyak, Rhawn Denniston

Geoscience Faculty Research

The arid southwestern United States is susceptible to sustained droughts that impact water resources and economic activity for millions of residents. Previous work has not systematically investigated the structure, timing, and possible forcings of Holocene Great Basin sub‐orbital hydroclimate changes, impeding our ability to understand the potential future controls on Southwestern aridity. The objective of this paper is to constrain the potential forcings on Holocene aridity and temperature, via comparison of new high‐resolution speleothem data, an Aridity Index synthesizing hydroclimate records, and linkages of Southwestern paleoclimate to other regions. The high‐resolution data from Leviathan Cave provide a paleoclimate record since …

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Non-Adiabatic Quantum Dynamics Of The Ultracold Li+Lina→ Li2+Na Chemical Reaction, B. K. Kendrick, M. Li, H. Li, S. Kotochigova, J. F.E. Croft, Balakrishnan Naduvalath Jun 2020

Non-Adiabatic Quantum Dynamics Of The Ultracold Li+Lina→ Li2+Na Chemical Reaction, B. K. Kendrick, M. Li, H. Li, S. Kotochigova, J. F.E. Croft, Balakrishnan Naduvalath

Chemistry and Biochemistry Faculty Research

We report non-adiabatic dynamics of the Li+LiNa→Li2+Na chemical reaction at cold and ultracold temperatures employing accurate ab initio electronic potential energy surfaces in a quantum dynamics formulation employing a diabatic representation. Results are compared against those from a single adiabatic ground state potential energy surface and a universal model based on the long-range interaction potential. We discuss signatures of non-universal behavior in the total rate coefficients as well as strong non-adiabatic effects in the state-to-state rotationally resolved rate coefficients.

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Promoting Change Within Special Education Teacher Preparation Programs: A Collision Of Needs, Cori M. More, Wendy J. Rodgers Jun 2020

Promoting Change Within Special Education Teacher Preparation Programs: A Collision Of Needs, Cori M. More, Wendy J. Rodgers

Educational & Clinical Studies Faculty Research

The United States is experiencing a systemic teacher shortage (Sutcher et al., 2016). This trend is not new to the field of special education, which has been experiencing teacher shortages for decades (Boe, 2006; McLeskey & Billingsley, 2008; U.S. Department of Education, 2020). To address these critical shortages of teachers in the field, states have created Alternative Routes to Licensure (ARL) options, which are commonly seen as non-traditional approaches to gaining teaching credentials. Although the disruptive practice of ARL is already in place, the evidence to support its effectiveness is not. This paper explores the experiences of junior faculty members …

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Requirements For Gravitational Collapse In Planetesimal Formation - The Impact Of Scales Set By Kelvin - Helmholtz And Nonlinear Streaming Instability, Konstantin Gerbig, Ruth A. Murray-Clay, Hubert Klahr, Hans Baehr Jun 2020

Requirements For Gravitational Collapse In Planetesimal Formation - The Impact Of Scales Set By Kelvin - Helmholtz And Nonlinear Streaming Instability, Konstantin Gerbig, Ruth A. Murray-Clay, Hubert Klahr, Hans Baehr

Physics & Astronomy Faculty Research

The formation of planetesimals is a challenging problem in planet formation theory. A prominent scenario for overcoming dust growth barriers is the gravitational collapse of locally over-dense regions, shown to robustly produce ~100 km–sized objects. Still, the conditions under which planetesimal formation occurs remain unclear. For collapse to proceed, the self-gravity of an over-density must overcome stellar tidal disruption on large scales and turbulent diffusion on small scales. Here, we relate the scales of streaming and Kelvin–Helmholtz instability (KHI), which both regulate particle densities on the scales of gravitational collapse, directly to planetesimal formation. We support our analytic findings by …

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Sacrificial Piles As Scour Countermeasures In River Bridges A Numerical Study Using Flow-3d, Mohammad Nazari-Sharabian, Aliasghar Nazari-Sharabian, Moses Karakouzian, Mehrdad Karami Jun 2020

Sacrificial Piles As Scour Countermeasures In River Bridges A Numerical Study Using Flow-3d, Mohammad Nazari-Sharabian, Aliasghar Nazari-Sharabian, Moses Karakouzian, Mehrdad Karami

Civil and Environmental Engineering and Construction Faculty Research

Scour is defined as the erosive action of flowing water, as well as the excavating and carrying away materials from beds and banks of streams, and from the vicinity of bridge foundations, which is one of the main causes of river bridge failures. In the present study, implementing a numerical approach, and using the FLOW-3D model that works based on the finite volume method (FVM), the applicability of using sacrificial piles in different configurations in front of a bridge pier as countermeasures against scouring is investigated. In this regard, the numerical model was calibrated based on an experimental study on …

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Neogene Retroarc Foreland Basin Evolution, Sediment Provenance, And Magmatism In Response To Flat Slab Subduction, Western Argentina, Tomas N. Capaldi, Brian K. Horton, N. Ryan Mckenzie, Chelsea Mackaman-Lofland, Daniel F. Stockli, Gustavo Ortiz, Patricia Alvarado May 2020

Neogene Retroarc Foreland Basin Evolution, Sediment Provenance, And Magmatism In Response To Flat Slab Subduction, Western Argentina, Tomas N. Capaldi, Brian K. Horton, N. Ryan Mckenzie, Chelsea Mackaman-Lofland, Daniel F. Stockli, Gustavo Ortiz, Patricia Alvarado

Geoscience Faculty Research

Understanding the effects of flat slab subduction on mountain building, arc magmatism, and basin evolution is fundamental to convergent‐margin tectonics, with implications for potential feedbacks among geodynamic, magmatic, and surface processes. New stratigraphic and geochronological constraints on Cenozoic sedimentation and magmatism in the southern Central Andes of Argentina (31°S) reveal shifts in volcanism, foreland/hinterland basin development, sediment accumulation, and provenance as the retroarc region was structurally partitioned during slab flattening. Detrital zircon U‐Pb age distributions from the western (Calingasta basin), central (Talacasto and Albarracín basins), and eastern (Bermejo foreland basin) segments of the retroarc basin system preserve syndepositional volcanism and …

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Building Engineering Awareness: Problem Based Learning Approach For Stem Integration, Abeera P. Rehmat, Kendall Hartley May 2020

Building Engineering Awareness: Problem Based Learning Approach For Stem Integration, Abeera P. Rehmat, Kendall Hartley

Teaching and Learning Faculty Research

Educators in the twenty-first century need to think of innovative ways to engage and prepare students for current and future challenges while cultivating an interest among students in STEM disciplines. This study sought to investigate the impact of problem-based learning on students’ content knowledge and critical thinking towards STEM. This study employed a quasi-experimental repeated measure design. Instruments such as STEM content assessments and a standardized critical thinking test were employed for data collection. Analysis was conducted using a mixed repeated measure between-within subject analysis of variance (ANOVA). The results revealed a significant difference (p < . 05) between problem-based learning and traditional learning groups in regard to their content knowledge and critical thinking skills.

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A Mildly Relativistic Outflow From The Energentic, Fast-Rising Blue Optical Transient Css161010 In A Dwarf Galaxy, Deanne L. Coppejans, R. Margutti, G. Terreran, A. J. Nayana, E. R. Coughlin, T. Laskar, K. D. Alexander, M. Bietenholz, D. Caprioli, P. Chandra, M. R. Drout, D. Frederiks, C. Frohmaier, K. H. Hurley, C. S. Kochanek, M. Macleod, A. Meisner, P. E. Nugent, A. Ridnaia, D. J. Sand, D. Svinkin, C. Ward, S. Yang, A. Baldeschi, I. V. Chilingarian, Y. Dong, C. Esquivia, W. Fong, C. Guidorzi, P. Lundqvist, D. Milisavljevic May 2020

A Mildly Relativistic Outflow From The Energentic, Fast-Rising Blue Optical Transient Css161010 In A Dwarf Galaxy, Deanne L. Coppejans, R. Margutti, G. Terreran, A. J. Nayana, E. R. Coughlin, T. Laskar, K. D. Alexander, M. Bietenholz, D. Caprioli, P. Chandra, M. R. Drout, D. Frederiks, C. Frohmaier, K. H. Hurley, C. S. Kochanek, M. Macleod, A. Meisner, P. E. Nugent, A. Ridnaia, D. J. Sand, D. Svinkin, C. Ward, S. Yang, A. Baldeschi, I. V. Chilingarian, Y. Dong, C. Esquivia, W. Fong, C. Guidorzi, P. Lundqvist, D. Milisavljevic

Physics & Astronomy Faculty Research

We present X-ray and radio observations of the Fast Blue Optical Transient CRTS-CSS161010 J045834−081803 (CSS161010 hereafter) at t = 69–531 days. CSS161010 shows luminous X-ray (L x ~ 5 × 1039 erg s−1) and radio (L ν ~ 1029 erg s−1 Hz−1) emission. The radio emission peaked at ~100 days post-transient explosion and rapidly decayed. We interpret these observations in the context of synchrotron emission from an expanding blast wave. CSS161010 launched a mildly relativistic outflow with velocity Γβc ≥ 0.55c at ~100 days. This is faster than the non-relativistic AT 2018cow (Γβc ~ 0.1c) and closer to ZTF18abvkwla (Γβc …

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Thermotropic Liquid-Crystalline And Light-Emitting Properties Of Bis(4-Aalkoxyphenyl) Viologen Bis(Triflimide) Salts, Pradip K. Bhowmik, Muhammed Kareem M. Al-Karawi, Shane T. Killarney, Erenz J. Dizon, Anthony Chang, Jongin Kim, Si L. Chen, Ronald Carlo G. Principe, Andy Ho, Haesook Han May 2020

Thermotropic Liquid-Crystalline And Light-Emitting Properties Of Bis(4-Aalkoxyphenyl) Viologen Bis(Triflimide) Salts, Pradip K. Bhowmik, Muhammed Kareem M. Al-Karawi, Shane T. Killarney, Erenz J. Dizon, Anthony Chang, Jongin Kim, Si L. Chen, Ronald Carlo G. Principe, Andy Ho, Haesook Han

Chemistry and Biochemistry Faculty Research

A series of bis(4-alkoxyphenyl) viologen bis(triflimide) salts with alkoxy chains of different lengths were synthesized by the metathesis reaction of respective bis(4-alkoxyphenyl) viologen dichloride salts, which were in turn prepared from the reaction of Zincke salt with the corresponding 4-n-alkoxyanilines, with lithium triflimide in methanol. Their chemical structures were characterized by 1H and 13C nuclear magnetic resonance spectra and elemental analysis. Their thermotropic liquid-crystalline (LC) properties were examined by differential scanning calorimetry, polarizing optical microscopy, and variable temperature X-ray diffraction. Salts with short length alkoxy chains had crystal-to-liquid transitions. Salts of intermediate length alkoxy chains showed both crystal-to-smectic A (SmA) …

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The Planetary Luminosity Problem: " Missing Planets" And The Observational Consequences Of Episodi Accretion, Sean D. Brittain, Joan R. Najita, Ruobing Dong, Zhaohuan Zhu May 2020

The Planetary Luminosity Problem: " Missing Planets" And The Observational Consequences Of Episodi Accretion, Sean D. Brittain, Joan R. Najita, Ruobing Dong, Zhaohuan Zhu

Physics & Astronomy Faculty Research

The high occurrence rates of spiral arms and large central clearings in protoplanetary disks, if interpreted as signposts of giant planets, indicate that gas giants commonly form as companions to young stars (Myr) at orbital separations of 10–300 au. However, attempts to directly image this giant planet population as companions to more mature stars (>10 Myr) have yielded few successes. This discrepancy could be explained if most giant planets form by "cold start," i.e., by radiating away much of their formation energy as they assemble their mass, rendering them faint enough to elude detection at later times. In that …

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Gw Ori: Interactions Between A Triple-Star System And Its Circumtriple Disk In Action, Jiaquig Bi, Nienke Van Der Marel, Ruobing Dong, Takayuki Muto, Rebecca G. Martin, Jeremy L. Smallwood, Jun Hashimoto, Hauyu Baobab Liu, Hideko Nomura, Yasuhiro Hasegawa, Michihiro Takami, Mihoko Konishi, Munetake Momose, Kazuhiro D. Kanagawa, Akimasa Kataoka, Tomohiro Ono, Michael L. Sitko, Sanemichi Z. Takahashi, Kengo Tomida, Takashi Tsukagoshi May 2020

Gw Ori: Interactions Between A Triple-Star System And Its Circumtriple Disk In Action, Jiaquig Bi, Nienke Van Der Marel, Ruobing Dong, Takayuki Muto, Rebecca G. Martin, Jeremy L. Smallwood, Jun Hashimoto, Hauyu Baobab Liu, Hideko Nomura, Yasuhiro Hasegawa, Michihiro Takami, Mihoko Konishi, Munetake Momose, Kazuhiro D. Kanagawa, Akimasa Kataoka, Tomohiro Ono, Michael L. Sitko, Sanemichi Z. Takahashi, Kengo Tomida, Takashi Tsukagoshi

Physics & Astronomy Faculty Research

GW Ori is a hierarchical triple system with a rare circumtriple disk. We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of 1.3 mm dust continuum and 12CO J = 2 − 1 molecular gas emission of the disk. For the first time, we identify three dust rings in the GW Ori disk at ~46, 188, and 338 au, with estimated dust mass of 74, 168, and 245 Earth masses, respectively. To our knowledge, its outermost ring is the largest dust ring ever found in protoplanetary disks. We use visibility modeling of dust continuum to show that the disk has misaligned …

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Hyperpolarizability Dispersion Measured For Cs2 Vapor, Rodrigo N. Fernandez, David P. Shelton May 2020

Hyperpolarizability Dispersion Measured For Cs2 Vapor, Rodrigo N. Fernandez, David P. Shelton

Physics & Astronomy Faculty Research

The second hyperpolarizability (��) of carbon disulfide (CS2) is measured by gas-phase electric-field-induced second-harmonic generation for laser wavelengths in the range 765–1064 nm. The observed hyperpolarizability is decomposed into electronic (����) and vibrational (����) contributions, and the dispersion curve for ���� is extrapolated to the static limit, with the result of ����0=12558±93 atomic units =7.83±0.06×10−61C4m4J−3=6.33±0.0×10−36 esu (Taylor series convention). The results of this experiment agree with other recent nonlinear optical measurements and theoretical calculations.

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Computational Study Of The Time Relaxation Model With High Order Deconvolution Operator, Jeffrey Belding, Monika Neda, Fran Pahlevani May 2020

Computational Study Of The Time Relaxation Model With High Order Deconvolution Operator, Jeffrey Belding, Monika Neda, Fran Pahlevani

Mathematical Sciences Faculty Research

This paper presents a computational investigation for a time relaxation regularization of Navier–Stokes equations known as Time Relaxation Model, TRM, and its corresponding sensitivity equations. The model generates a regularization based on both filtering and deconvolution. We discretize the equations of TRM and the corresponding sensitivity equations using finite element in space and Crank–Nicolson in time. The step problem and the shear layer roll-up benchmark is used to computationally test the performance of TRM across different orders of deconvolution operator as well as the sensitivity of the shear layer computations of the model with respect to the variation of time …

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A Note On Eulerian Numbers And Toeplitz Matrices, Tian-Xiao He, Peter J.-S. Shiue May 2020

A Note On Eulerian Numbers And Toeplitz Matrices, Tian-Xiao He, Peter J.-S. Shiue

Mathematical Sciences Faculty Research

This note presents a new formula of Eulerian numbers derived from Toeplitz matrices via Riordan array approach.

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A Fast Radio Burst Discovered In Fast Drift Scan Survey, Weiwei Zhu, Di Li, Rui Luo, Chenchen Miao, Bing Zhang, Laura Spitler, Duncan Lorimer, Michael Kramer, David Champion, Youling Yue, Andrew Cameron, Marilyn Cruces, Ran Duan, Yi Feng, Jun Han, George Hobbs, Chenhui Niu, Jiarui Niu, Zhichen Pan, Lei Qian, Dai Shi, Ningyu Tang, Pei Wang, Hongfeng Wang, Mao Yuan, Lei Zhang, Xinxin Zhang, Shuyun Cao, Li Feng, Hengqian Gan, Long Gao May 2020

A Fast Radio Burst Discovered In Fast Drift Scan Survey, Weiwei Zhu, Di Li, Rui Luo, Chenchen Miao, Bing Zhang, Laura Spitler, Duncan Lorimer, Michael Kramer, David Champion, Youling Yue, Andrew Cameron, Marilyn Cruces, Ran Duan, Yi Feng, Jun Han, George Hobbs, Chenhui Niu, Jiarui Niu, Zhichen Pan, Lei Qian, Dai Shi, Ningyu Tang, Pei Wang, Hongfeng Wang, Mao Yuan, Lei Zhang, Xinxin Zhang, Shuyun Cao, Li Feng, Hengqian Gan, Long Gao

Physics & Astronomy Faculty Research

We report the discovery of a highly dispersed fast radio burst (FRB), FRB 181123, from an analysis of ~1500 hr of drift scan survey data taken using the Five-hundred-meter Aperture Spherical radio Telescope (FAST). The pulse has three distinct emission components, which vary with frequency across our 1.0–1.5 GHz observing band. We measure the peak flux density to be... (See full abstract in article).

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Determination Of The Optimal Location For Constructing Solar Photovoltaic Farms Based On Multi-Criteria Decision System And Dempster–Shafer Theory, Marzieh Mokarram, Mohammad J. Mokarram, Mohammad R. Khosravi, Ali Saber, Akbar Rahideh May 2020

Determination Of The Optimal Location For Constructing Solar Photovoltaic Farms Based On Multi-Criteria Decision System And Dempster–Shafer Theory, Marzieh Mokarram, Mohammad J. Mokarram, Mohammad R. Khosravi, Ali Saber, Akbar Rahideh

Civil and Environmental Engineering and Construction Faculty Research

Considering environmental concerns regarding air pollution which is induced by burning fossil fuels to generate electrical power, utilizing solar energy as a green and sustainable energy source is of great interest. This study proposes a novel framework to determine the optimal location for constructing solar photovoltaic (PV) farms. To locate the suitable areas for PV farms, firstly, a fuzzy-based method is utilized to homogenize the input parameters, thereafter, the analytical hierarchy process (AHP) and Dempster-Shafer (DS) methods are independently used. In the AHP method, the proper weight for each input parameter is generated utilizing a pairwise comparison matrix. However, the …

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Hybrid Hospitality, John Gassaway May 2020

Hybrid Hospitality, John Gassaway

Hospitality Design Graduate Student Capstones

In order to understand the proposed coupled system, there must be an understanding of each component and how optimal performance of the system depends on sustainable architectural design. The basics of each component, a brief history and applicable case studies will be explained and presented starting with ground source thermal loops and then thermal mass (concrete walls). This will be followed by a more detailed explanation of how the components couple to form a functioning energy efficient system, how research can prove energy efficiency and how architectural design concepts can merge to influence sustainable hospitality design.

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Space Age Urbanism: A Master Plan For Spaceport America, Keiri Dueñas May 2020

Space Age Urbanism: A Master Plan For Spaceport America, Keiri Dueñas

Hospitality Design Graduate Student Capstones

This project imagines that by the year 2050, thousands of passengers will walk through the terminal gate of Spaceport America in order to board a hyper or supersonic flight. But currently there are no existing commercial flights and accommodations within a 25 mile radius to Spaceport America. Alternatively, this project attempts to provide future developers with the tools needed for "space age" developments. Thus, this project seeks to serve as a driver for a new type of architecture called "space-age" urbanism, where the architecture aims to re-establish the American "excitement" found in the 1960's.

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Assessing The Potential For Greater Solar Development In West Texas, Usa, Dale D. Devitt, M. H. Young, J. P. Pierre May 2020

Assessing The Potential For Greater Solar Development In West Texas, Usa, Dale D. Devitt, M. H. Young, J. P. Pierre

Life Sciences Faculty Research

As population and economies continue to grow on a global scale, so too does the demand for energy. To improve reliability and independence of energy supplies, the U.S. and many other countries are seeking internally-sourced renewable energy; solar is one such renewable-energy source that meets these criteria. However, all energy sources exert some environmental impacts. In the case of solar, direct impacts stem mostly from alteration of land needed to host infrastructure. Understanding the environmental upside and downside potential of solar energy systems allows a more comprehensive, side-by-side comparison with different energy sources. In this article, we focus on the …

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