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2017

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Articles 2941 - 2970 of 12521

Full-Text Articles in Physical Sciences and Mathematics

Towards Food Service Sustainability In Suburban Environments By Optimally Locating Shared Anaerobic Digester Units, Rebecca Loraamm, Joni Downs, Robert Alonso Bair, Daniel Yeh Aug 2017

Towards Food Service Sustainability In Suburban Environments By Optimally Locating Shared Anaerobic Digester Units, Rebecca Loraamm, Joni Downs, Robert Alonso Bair, Daniel Yeh

Suburban Sustainability

Anaerobic digestion is an effective method for reducing food waste at the consumer level. Drawbacks associated with this strategy include high construction costs for multiple digester units and limited public awareness of the method’s commercial potential. Given the large scale problem of food waste, an approach establishing community partnerships between local businesses and primary schools is offered to combat the problem of food waste. Optimizing the placement of shared digester units enabling utilization by multiple stakeholders is the suggested mitigation method. This research explores application of the p-median problem to determine the set of optimal sites for shared anaerobic digester …


Measurement Of Jet Quenching With Semi-Inclusive Hadron+Jet Distributions In Au + Au Collisions At √SNn = 200 Gev, L. Adamczyk, James K. Adkins, G. Agakishiev, M. M. Aggarwal, Z. Ahammed, N. N. Ajitanand, I. Alekseev, D. M. Anderson, R. Aoyama, A. Aparin, D. Arkhipkin, E. C. Aschenauer, M. U. Ashraf, A. Attri, G. S. Averichev, X. Bai, V. Bairathi, A. Behera, R. Bellwied, A. Bhasin, A. K. Bhati, P. Bhattarai, J. Bielcik, J. Bielcikova, L. C. Bland, I. G. Bordyuzhin, J. Bouchet, J. D. Brandenburg, A. V. Brandin, D. Brown, Renee H. Fatemi, Suvarna Ramachandran Aug 2017

Measurement Of Jet Quenching With Semi-Inclusive Hadron+Jet Distributions In Au + Au Collisions At √SNn = 200 Gev, L. Adamczyk, James K. Adkins, G. Agakishiev, M. M. Aggarwal, Z. Ahammed, N. N. Ajitanand, I. Alekseev, D. M. Anderson, R. Aoyama, A. Aparin, D. Arkhipkin, E. C. Aschenauer, M. U. Ashraf, A. Attri, G. S. Averichev, X. Bai, V. Bairathi, A. Behera, R. Bellwied, A. Bhasin, A. K. Bhati, P. Bhattarai, J. Bielcik, J. Bielcikova, L. C. Bland, I. G. Bordyuzhin, J. Bouchet, J. D. Brandenburg, A. V. Brandin, D. Brown, Renee H. Fatemi, Suvarna Ramachandran

Physics and Astronomy Faculty Publications

The STAR Collaboration reports the measurement of semi-inclusive distributions of charged-particle jets recoiling from a high transverse momentum hadron trigger, in central and peripheral Au + Au collisions at √sNN = 200 GeV. Charged jets are reconstructed with the anti-kT algorithm for jet radii R between 0.2 and 0.5 and with low infrared cutoff of track constituents (pT > 0.2 GeV/c). A novel mixed-event technique is used to correct the large uncorrelated background present in heavy ion collisions. Corrected recoil jet distributions are reported at midrapidity, for charged-jet transverse momentum pchT,jet < GeV/c. Comparison is made to similar measurements for Pb + Pb collisions at √s = …


Card Tricks: A Workflow For Scalability And Dynamic Content Creation Using Paper2d And Unreal Engine 4, Owen Gottlieb, Dakota Herold, Edward Amidon Aug 2017

Card Tricks: A Workflow For Scalability And Dynamic Content Creation Using Paper2d And Unreal Engine 4, Owen Gottlieb, Dakota Herold, Edward Amidon

Presentations and other scholarship

In this paper, we describe the design and technological methods of

our dynamic sprite system in Lost & Found, a table-top-to-mobile

card game designed to improve literacy regarding prosocial

aspects of religious legal systems, specifically, collaboration and

cooperation. Harnessing the capabilities of Unreal Engine’s

Paper2D system, we created a dynamic content creation pipeline

that empowered our game designers so that they could rapidly

iterate on the game’s systems and balance externally from the

engine. Utilizing the Unreal Blueprint component system we were

also able to modularize each actor during runtime as data may be

changed. The technological approach behind Lost …


Linear Feedback Stabilization Of A Dispersively Monitored Qubit, Taylor Lee Patti, Areeya Chantasri, Luis Pedro García-Pintos, Andrew N. Jordan, Justin Dressel Aug 2017

Linear Feedback Stabilization Of A Dispersively Monitored Qubit, Taylor Lee Patti, Areeya Chantasri, Luis Pedro García-Pintos, Andrew N. Jordan, Justin Dressel

Mathematics, Physics, and Computer Science Faculty Articles and Research

The state of a continuously monitored qubit evolves stochastically, exhibiting competition between coherent Hamiltonian dynamics and diffusive partial collapse dynamics that follow the measurement record. We couple these distinct types of dynamics together by linearly feeding the collected record for dispersive energy measurements directly back into a coherent Rabi drive amplitude. Such feedback turns the competition cooperative and effectively stabilizes the qubit state near a target state. We derive the conditions for obtaining such dispersive state stabilization and verify the stabilization conditions numerically.We include common experimental nonidealities, such as energy decay, environmental dephasing, detector efficiency, and feedback delay, and show …


Dual Modality Code Explanations For Novices: Unexpected Results, Briana B. Morrison Aug 2017

Dual Modality Code Explanations For Novices: Unexpected Results, Briana B. Morrison

Computer Science Faculty Proceedings & Presentations

The research in both cognitive load theory and multimedia principles for learning indicates presenting information using both diagrams and accompanying audio explanations yields better learning performance than using diagrams with text explanations. While this is a common practice in introductory programming courses, often called "live coding," it has yet to be empirically tested. This paper reports on an experiment to determine if auditory explanations of code result in improved learning performance over written explanations. Students were shown videos explaining short code segments one of three ways: text only explanations, auditory only explanations, or both text and auditory explanations, thus replicating …


Hydroformylation And Aldehyde-Water Shift Catalysis By Dirhodium Tetraphosphine Complexes, Marshall Douglas Moulis Aug 2017

Hydroformylation And Aldehyde-Water Shift Catalysis By Dirhodium Tetraphosphine Complexes, Marshall Douglas Moulis

LSU Doctoral Dissertations

The use of a unique tetraphosphine ligand (et,ph-P4) allows for the chelating of two rhodium centers to perform bimetallic coopertivity in hydroformylation reactions to better the yields the linear aldehyde product. The proposed catalyst is [Rh2(μ-H)2(CO)4(rac-et,ph-P4)]2+ and has been studied by in situ FT-IR and NMR. When tested in a polar phasic acetone/water (30 % by vol.), the catalyst forms a monocationic system [Rh2(μ-H)2(CO)4(rac-et,ph-P4)]+ that has an initial TOF of 26 min-1, selectivity of 27:1 L:B, and low byproducts of …


Poly(Ethyl Glyoxylate) Solid-Core Particles For Drug Delivery, Michael Thomas Gambles Aug 2017

Poly(Ethyl Glyoxylate) Solid-Core Particles For Drug Delivery, Michael Thomas Gambles

Electronic Thesis and Dissertation Repository

The ability to trigger the degradation of polymeric nanoparticles (NPs) by a specific stimulus can provide a method of improved drug targeting and selective release capabilities in vivo. The challenge for most polymeric drug delivery systems remains the necessity for many stimuli events to trigger the release of cargo. Polymeric nanotechnology containing “self-immolative polymers” looks to alleviate the reliance on high concentrations of stimuli by undergoing complete end-to-end depolymerization via a single stimulus-mediated reaction of an end-cap. Herein, NPs were developed using poly(ethyl glyoxylate) (PEtG) blended with poly(d,l-lactic acid) (PLA) to encapsulate a hydrophobic cargo to be released upon …


Aligning Natural Resource Conservation, Flood Hazard Mitigation, And Social Vulnerability Remediation In Florida, Juliano Calil, Sarah Newkirk Aug 2017

Aligning Natural Resource Conservation, Flood Hazard Mitigation, And Social Vulnerability Remediation In Florida, Juliano Calil, Sarah Newkirk

Journal of Ocean and Coastal Economics

Flooding continues to be the most common and damaging of all natural disasters in the United States. In 2016, twelve individual weather and climate events caused more than $1billion in damages each. During 2016, the U.S. was hit by at least five once-in-1,000 years precipitation events, and severe floods resulted in more than $17 billion in damages. Currently, more than 5.5 million active policies under the National Flood Insurance Program, underwrite more than $1.6 trillion in assets. Since 1978, NFIP has paid out more than $38 billion in claims – nearly 30% was paid to the 1% of properties classified …


Ab Initio Study Of The Mechanism Of Carboxylic Acids Cross-Ketonization On Monoclinic Zirconia Via Condensation To Beta-Keto Acids Followed By Decarboxylation, Alexey Ignatchenko, James P. Mcsally, Marc D. Bishop, Joshua Zweigle Aug 2017

Ab Initio Study Of The Mechanism Of Carboxylic Acids Cross-Ketonization On Monoclinic Zirconia Via Condensation To Beta-Keto Acids Followed By Decarboxylation, Alexey Ignatchenko, James P. Mcsally, Marc D. Bishop, Joshua Zweigle

Chemistry Faculty/Staff Publications

Catalytic mechanism of acetic and isobutyric acids mixture conversion into two symmetrical and one cross-ketone product on monoclinic zirconia (111) surface was extensively modeled by Density Functional Theory for periodic structures. Several options were evaluated for each mechanistic step by calculating their reaction rate constants. The best option for each kinetically relevant step was chosen by matching calculated rates of reaction with experimental values.

Four zirconium surface atoms define each catalytic site. The most favorable pathway includes condensation between surface carboxylates, one of which is enolized through alpha-hydrogen abstraction by lattice oxygen. Condensation of gas phase molecules with the enolized …


Cloud Droplets To Drizzle: Contribution Of Transition Drops To Microphysical And Optical Properties Of Marine Stratocumulus Clouds, S Glienke, A. Kostinski, J P. Fugal, R. A. Shaw, S Borrmann, J Stith Aug 2017

Cloud Droplets To Drizzle: Contribution Of Transition Drops To Microphysical And Optical Properties Of Marine Stratocumulus Clouds, S Glienke, A. Kostinski, J P. Fugal, R. A. Shaw, S Borrmann, J Stith

Department of Physics Publications

Aircraft measurements of the ubiquitous marine stratocumulus cloud type, with over 3000 km of in situ data from the Pacific during the Cloud System Evolution in the Trades experiment, show the ability of the Holographic Detector for Clouds (HOLODEC) instrument to smoothly interpolate the small and large droplet data collected with Cloud Droplet Probe and 2DC instruments. The combined, comprehensive instrument suite reveals a surprisingly large contribution in the predrizzle size range of 40–80 μm (transition droplets, or drizzlets), a range typically not measured and assumed to reside in a condensation‐to‐collision minimum between cloud droplet and drizzle modes. Besides shedding …


Implementing An Environmental Citizen Science Project: Strategies And Concerns From Educators’ Perspectives, Yurong He, Andrea Wiggins Aug 2017

Implementing An Environmental Citizen Science Project: Strategies And Concerns From Educators’ Perspectives, Yurong He, Andrea Wiggins

Information Systems and Quantitative Analysis Faculty Publications

Citizen science seems to have a natural alignment with environmental and science education, but incorporating citizen science projects into education practices is still a challenge for educators from different education contexts. Based on participant observation and interview data, this paper describes the strategies educators identified for implementing an environmental citizen science project in different education contexts (i.e., classroom teaching, aquarium exhibits, and summer camp) and discusses the practical concerns influencing independent implementation by educators. The results revealed different implementation strategies that are shaped by four categories of constraints: 1) organizational and institutional policies, 2) educators’ time and material resources, 3) …


Measurement Of The Inclusive Energy Spectrum In The Very Forward Direction In Proton-Proton Collisions At √S=13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration Aug 2017

Measurement Of The Inclusive Energy Spectrum In The Very Forward Direction In Proton-Proton Collisions At √S=13 Tev, M M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, D Noonan, Tuhin S. Roy, Francisco X. Yumiceva, Cms Collaboration

Aerospace, Physics, and Space Science Faculty Publications

The differential cross section for inclusive particle production as a function of energy in proton-proton collisions at a center-of-mass energy of 13 TeV is measured in the very forward region of the CMS detector. The measurement is based on data collected with the CMS apparatus at the LHC, and corresponds to an integrated luminosity of 0.34 μb−1. The energy is measured in the CASTOR calorimeter, which covers the pseudorapidity region −6.6 < η < −5.2. The results are given as a function of the total energy deposited in CASTOR, as well as of its electromagnetic and hadronic components. The spectra are sensitive to the modeling of multiparton interactions in pp collisions, and provide new constraints for hadronic interaction models used in collider and in high energy cosmic ray physics.


Examination And Comparison Of The Performance Of Common Non-Parametric And Robust Regression Models, Gregory F. Malek Aug 2017

Examination And Comparison Of The Performance Of Common Non-Parametric And Robust Regression Models, Gregory F. Malek

Electronic Theses and Dissertations

ABSTRACT

Examination and Comparison of the Performance of Common Non-Parametric and Robust Regression Models

By

Gregory Frank Malek

Stephen F. Austin State University, Masters in Statistics Program,

Nacogdoches, Texas, U.S.A.

g_m_2002@live.com

This work investigated common alternatives to the least-squares regression method in the presence of non-normally distributed errors. An initial literature review identified a variety of alternative methods, including Theil Regression, Wilcoxon Regression, Iteratively Re-Weighted Least Squares, Bounded-Influence Regression, and Bootstrapping methods. These methods were evaluated using a simple simulated example data set, as well as various real data sets, including math proficiency data, Belgian telephone call data, and faculty …


Towards A Privacy Rule Conceptual Model For Smart Toys, Laura Rafferty, Patrick C. K. Hung, Marcelo Fantinato, Sarajane Marques Peres, Farkhund Iqbal, Sy-Yen Kuo, Shih-Chia Huang Aug 2017

Towards A Privacy Rule Conceptual Model For Smart Toys, Laura Rafferty, Patrick C. K. Hung, Marcelo Fantinato, Sarajane Marques Peres, Farkhund Iqbal, Sy-Yen Kuo, Shih-Chia Huang

All Works

A smart toy is defined as a device consisting of a physical toy component that connects to one or more toy computing services to facilitate gameplay in the cloud through networking and sensory technologies to enhance the functionality of a traditional toy. A smart toy in this context can be effectively considered an Internet of Things (IoT) with Artificial Intelligence (AI) which can provide Augmented Reality (AR) experiences to users. In this paper, the first assumption is that children do not understand the concept of privacy and the children do not know how to protect themselves online, especially in a …


Limb Darkening And Planetary Transits: Testing Center-To-Limb Intensity Variations And Limb-Darkening Directly From Model Stellar Atmospheres, Hilding R. Neilson, Joseph T. Mcneil, Richard Ignace, John B. Lester Aug 2017

Limb Darkening And Planetary Transits: Testing Center-To-Limb Intensity Variations And Limb-Darkening Directly From Model Stellar Atmospheres, Hilding R. Neilson, Joseph T. Mcneil, Richard Ignace, John B. Lester

ETSU Faculty Works

The transit method, employed by Microvariability and Oscillation of Stars (MOST), Kepler, and various ground-based surveys has enabled the characterization of extrasolar planets to unprecedented precision. These results are precise enough to begin to measure planet atmosphere composition, planetary oblateness, starspots, and other phenomena at the level of a few hundred parts per million. However, these results depend on our understanding of stellar limb darkening, that is, the intensity distribution across the stellar disk that is sequentially blocked as the planet transits. Typically, stellar limb darkening is assumed to be a simple parameterization with two coefficients that are derived …


Window Inserts And The People Adopting Them: Building Sustainable Communities In Maine, Daniel Sean Mistro Aug 2017

Window Inserts And The People Adopting Them: Building Sustainable Communities In Maine, Daniel Sean Mistro

Electronic Theses and Dissertations

Residents of Maine face a large monetary expense to heat their homes in the winter. In Maine it takes 540 gallons of heating oil each year to heat a typical home [1]. Interior window inserts may be a practical solution to improve comfort, save money, and consume less environmentally harmful fossil fuels during cold winter months. The window inserts discussed in this paper are custom measured to fit into a window and consist of a wooden frame that is wrapped in two layers of polyolefin film and weather stripped for a snug fit. Commercial inserts cost $20-$36/square foot, or approximately …


Assessing A Fluorescence Spectroscopy Method For In-Situ Microbial Drinking Water Quality, Taylor Jeffery Sharpe Aug 2017

Assessing A Fluorescence Spectroscopy Method For In-Situ Microbial Drinking Water Quality, Taylor Jeffery Sharpe

Dissertations and Theses

Waterborne disease is a significant contributor to the global burden of disease, in particular among high-risk populations in developing nations. State-of-the-art methods for the enumeration of microbial pathogens in drinking water sources have important limitations, including high initial cost, 24-48 hour delays in results, high staffing and facility requirements, and training requirements which all become especially problematic in the developing nation context.

A number of alternative approaches to microbial water quality testing have been proposed, with the goal of decreasing the required testing time, decreasing overall costs, leveraging appropriate technology approaches, or improving sensitivity or specificity of the water quality …


Soputan Volcano, Indonesia: Petrological Systematics Of Volatiles And Magmas And Their Bearing On Explosive Eruptions Of A Basalt Volcano, Syegi Lenarahmi Kunrat Aug 2017

Soputan Volcano, Indonesia: Petrological Systematics Of Volatiles And Magmas And Their Bearing On Explosive Eruptions Of A Basalt Volcano, Syegi Lenarahmi Kunrat

Dissertations and Theses

Soputan volcano is one of the few basaltic volcanoes among 127 active volcanoes in Indonesia. It is part of the Sempu-Soputan volcanic complex located south of Tondano Caldera, North Sulawesi and commonly produces both explosive eruptions with VEI 2-3 and effusive lava dome and flow eruptions. Over the last two decades, Soputan had thirteen eruptions, the most recent in 2016. Most eruptions started explosively, followed by dome growth and in some cases pyroclastic flows. Our study focuses on understanding the magmatic system of Soputan and what processes are responsible for its highly explosive eruptions, which are typically uncommon for a …


Physical Mechanisms Leading To The Coulomb Blockade And Coulomb Staircase Structures In Strongly Coupled Multi-Island Single-Electron Devices, Madhusudan A. Savaikar, Paul L. Bergstrom, John A. Jaszczak Aug 2017

Physical Mechanisms Leading To The Coulomb Blockade And Coulomb Staircase Structures In Strongly Coupled Multi-Island Single-Electron Devices, Madhusudan A. Savaikar, Paul L. Bergstrom, John A. Jaszczak

Paul Bergstrom

Controlled transport of electrons through tunnel junctions and their confinement by mesoscopic structures have opened up immense possibilities of single-electron device (SED) applications. The realization of a practical working SED has remained challenging largely owing to the poor understanding of the physics of operation of singe-electron tunneling devices, especially of those with multiple nanometer-sized islands. In this simulation study of one-dimensional (1D) multi-island chains, we propose physical mechanisms that lead to the coulomb blockade (CB) and coulomb staircase (CS) characteristics that are enhanced by the geometrical disorder in the chain. With increasing source-drain (VDS = VD − VS) bias, a …


New Flexible Channels For Room Temperature Tunneling Field Effect Transistors, Boyi Hao, Anjana Asthana, Paniz Khanmohammadi, Paul Bergstrom, Douglas R. Banyai, Madhusudan A. Savaikar, John A. Jaszczak, Yoke Khin Yap Aug 2017

New Flexible Channels For Room Temperature Tunneling Field Effect Transistors, Boyi Hao, Anjana Asthana, Paniz Khanmohammadi, Paul Bergstrom, Douglas R. Banyai, Madhusudan A. Savaikar, John A. Jaszczak, Yoke Khin Yap

Paul Bergstrom

Tunneling field effect transistors (TFETs) have been proposed to overcome the fundamental issues of Si based transistors, such as short channel effect, finite leakage current, and high contact resistance. Unfortunately, most if not all TFETs are operational only at cryogenic temperatures. Here we report that iron (Fe) quantum dots functionalized boron nitride nanotubes (QDs-BNNTs) can be used as the flexible tunneling channels of TFETs at room temperatures. The electrical insulating BNNTs are used as the one-dimensional (1D) substrates to confine the uniform formation of Fe QDs on their surface as the flexible tunneling channel. Consistent semiconductor-like transport behaviors under various …


Simulation Of Charge Transport In Multi-Island Tunneling Devices: Application To Disordered One-Dimensional Systems At Low And High Biases, Madhusudan A. Savaikar, Douglas R. Banyai, Paul Bergstrom, John A. Jaszczak Aug 2017

Simulation Of Charge Transport In Multi-Island Tunneling Devices: Application To Disordered One-Dimensional Systems At Low And High Biases, Madhusudan A. Savaikar, Douglas R. Banyai, Paul Bergstrom, John A. Jaszczak

Paul Bergstrom

Although devices have been fabricated displaying interesting single-electron transport characteristics, there has been limited progress in the development of tools that can simulate such devices based on their physical geometry over a range of bias conditions up to a few volts per junction. In this work, we present the development of a multi-island transport simulator, MITS, a simulator of tunneling transport in multi-island devices that takes into account geometrical and material parameters, and can span low and high source-drain biases. First, the capabilities of MITS are demonstrated by modeling experimentaldevices described in the literature, and showing that the simulated device …


Micro Dh: Digital Humanities At The Small Scale, Roopika Risam, Susan Edwards Aug 2017

Micro Dh: Digital Humanities At The Small Scale, Roopika Risam, Susan Edwards

Roopika Risam

Digital humanities practices are often understood in terms of significant scale: big data, large data sets, digital humanities centers (Terras et al. 2016; Kowalczyk et al. 2014; Borgman 2009; Kretzschmar 2009). This emphasis leads to the perception that projects cannot be completed without substantial access to financial resources, data, and labor (Prescott 2016; Hockey 2016; Evans and Rees 2012). While this can be the case, such presumptions serve as a deterrent to the development of an inclusive digital humanities community with representation across academic hierarchies (student, librarian, faculty), types of institutions (public, private, regional), and geographies (Global North, Global South). …


Time Varying Parameter Estimation Scheme For A Linear Stochastic Differential Equation.Pdf, Michael Otunuga Aug 2017

Time Varying Parameter Estimation Scheme For A Linear Stochastic Differential Equation.Pdf, Michael Otunuga

Olusegun Michael Otunuga

p, li { white-space: pre-wrap; }
In this work, an attempt is made to estimate time varying parameters in a linear stochastic differential equation. By defining $m_{k}$ as the local admissible sample/data observation size at time $t_{k}$, parameters and state at time $t_{k}$ are estimated using past data on interval $[t_{k-m_{k}+1}, t_{k}]$. We show that the parameter estimates at each time $t_{k}$ converge in probability to the true value of the parameters being estimated. A numerical simulation is presented by applying the local lagged adapted generalized method of moments (LLGMM) method to the stochastic differential models governing prices …


Catalytic Oxidation And Depolymerization Of Lignin In Aqueous Ionic Liquid, Lalitendu Das, Siquan Xu, Jian Shi Aug 2017

Catalytic Oxidation And Depolymerization Of Lignin In Aqueous Ionic Liquid, Lalitendu Das, Siquan Xu, Jian Shi

Biosystems and Agricultural Engineering Faculty Publications

Lignin is an integral part of the plant cell wall, which provides rigidity to plants, also contributes to the recalcitrance of the lignocellulosic biomass to biochemical and biological deconstruction. Lignin is a promising renewable feedstock for aromatic chemicals; however, an efficient and economic lignin depolymerization method needs to be developed to enable the conversion. In this study, we investigated the depolymerization of alkaline lignin in aqueous 1-ethyl-3-methylimidazolium acetate [C2C1Im][OAc] under oxidizing conditions. Seven different transition metal catalysts were screened in presence of H2O2 as oxidizing agent in a batch reactor. CoCl2 and …


Lanthanum-Mediated Dehydrogenation Of 1- And 2-Butynes: Spectroscopy And Formation Of La(C4H4) Isomers, Wenjin Cao, Dilrukshi C. Hewage, Dong-Sheng Yang Aug 2017

Lanthanum-Mediated Dehydrogenation Of 1- And 2-Butynes: Spectroscopy And Formation Of La(C4H4) Isomers, Wenjin Cao, Dilrukshi C. Hewage, Dong-Sheng Yang

Chemistry Faculty Publications

La atom reactions with 1-butyne and 2-butyne are carried out in a laser-vaporization molecular beam source. Both reactions yield the same La-hydrocarbon products from the dehydrogenation and carbon-carbon bond cleavage and coupling of the butynes. The dehydrogenated species La(C4H4) is characterized with mass-analyzed threshold ionization (MATI) spectroscopy and quantum chemical computations. The MATI spectra of La(C4H4) produced from the two reactions exhibit two identical transitions, each consisting of a strong origin band and several vibrational intervals. The two transitions are assigned to the ionization of two isomers: La(η4–CH2CCCH …


A Lab-On-Chip Phosphate Analyzer For Long-Term In Situ Monitoring At Fixed Observatories: Optimization And Performance Evaluation In Estuarine And Oligotrophic Coastal Waters, Maxime Grand, Geraldine Clinton-Bailey, Alexander Beaton, Allison Schaap, Thomas Johengen, Mario Tamburri, Douglas Connelly, Matthew Mowlem, Eric Achterberg Aug 2017

A Lab-On-Chip Phosphate Analyzer For Long-Term In Situ Monitoring At Fixed Observatories: Optimization And Performance Evaluation In Estuarine And Oligotrophic Coastal Waters, Maxime Grand, Geraldine Clinton-Bailey, Alexander Beaton, Allison Schaap, Thomas Johengen, Mario Tamburri, Douglas Connelly, Matthew Mowlem, Eric Achterberg

Faculty Publications

The development of phosphate sensors suitable for long-term in situdeployments in natural waters, is essential to improve our understanding of the distribution, fluxes, and biogeochemical role of this key nutrient in a changing ocean. Here, we describe the optimization of the molybdenum blue method for in situ work using a lab-on-chip (LOC) analyzer and evaluate its performance in the laboratory and at two contrasting field sites. The in situ performance of the LOC sensor is evaluated using hourly time-series data from a 56-day trial in Southampton Water (UK), as well as a month-long deployment in the subtropical oligotrophic waters of …


Entanglement Entropy With Background Gauge Fields, Bom Soo Kim Aug 2017

Entanglement Entropy With Background Gauge Fields, Bom Soo Kim

Physics and Astronomy Faculty Publications

We study the entanglement entropy, the Rényi entropy, and the mutual (Rényi) information of Dirac fermions on a 2 dimensional torus in the presence of constant gauge fields. We derive their general formulas using the equivalence between twisted boundary conditions and the background gauge fields. Novel and interesting physical consequences have been presented in arXiv:1705.01859. Here we provide detailed computations of the entropies and mutual information in a low temperature limit, a large radius limit, and a high temperature limit. The high temperature limit reveals rather different physical properties compared to those of the low temperature one: there exist …


Dijet Imbalance Measurements In Au + Au And Pp Collisions At √SNn = 200 Gev At Star, L. Adamczyk, James K. Adkins, G. Agakishiev, M. M. Aggarwal, Z. Ahammed, I. Alekseev, D. M. Anderson, R. Aoyama, A. Aparin, D. Arkhipkin, E. C. Aschenauer, M. U. Ashraf, A. Attri, G. S. Averichev, X. Bai, V. Bairathi, R. Bellwied, A. Bhasin, A. K. Bhati, P. Bhattarai, J. Bielcik, J. Bielcikova, L. C. Bland, I. G. Bordyuzhin, J. Bouchet, J. D. Brandenburg, A. V. Brandin, D. Brown, I. Bunzarov, J. Butterworth, Renee H. Fatemi, Suvarna Ramachandran Aug 2017

Dijet Imbalance Measurements In Au + Au And Pp Collisions At √SNn = 200 Gev At Star, L. Adamczyk, James K. Adkins, G. Agakishiev, M. M. Aggarwal, Z. Ahammed, I. Alekseev, D. M. Anderson, R. Aoyama, A. Aparin, D. Arkhipkin, E. C. Aschenauer, M. U. Ashraf, A. Attri, G. S. Averichev, X. Bai, V. Bairathi, R. Bellwied, A. Bhasin, A. K. Bhati, P. Bhattarai, J. Bielcik, J. Bielcikova, L. C. Bland, I. G. Bordyuzhin, J. Bouchet, J. D. Brandenburg, A. V. Brandin, D. Brown, I. Bunzarov, J. Butterworth, Renee H. Fatemi, Suvarna Ramachandran

Physics and Astronomy Faculty Publications

We report the first dijet transverse momentum asymmetry measurements from Au + Au and pp collisions at RHIC. The two highest-energy back-to-back jets reconstructed from fragments with transverse momenta above 2  GeV/c display a significantly higher momentum imbalance in heavy-ion collisions than in the pp reference. When reexamined with correlated soft particles included, we observe that these dijets then exhibit a unique new feature—momentum balance is restored to that observed in pp for a jet resolution parameter of R = 0.4, while rebalancing is not attained with a smaller value of R = 0.2.


Evolution Equations For Connected And Disconnected Sea Parton Distributions, Keh-Fei Liu Aug 2017

Evolution Equations For Connected And Disconnected Sea Parton Distributions, Keh-Fei Liu

Physics and Astronomy Faculty Publications

It has been revealed from the path-integral formulation of the hadronic tensor that there are connected sea and disconnected sea partons. The former is responsible for the Gottfried sum rule violation primarily and evolves the same way as the valence. Therefore, the Dokshitzer-Gribov-Lipatov-Altarelli-Parisi evolution equations can be extended to accommodate them separately. We discuss its consequences and implications vis-á-vis lattice calculations.


Construction And Passive Q-Switching Of A Ring-Cavity Erbium-Doped Fiber Laser Using Carbon Nanotubes As A Saturable Absorber, Austin Scott Aug 2017

Construction And Passive Q-Switching Of A Ring-Cavity Erbium-Doped Fiber Laser Using Carbon Nanotubes As A Saturable Absorber, Austin Scott

Graduate Theses - Physics and Optical Engineering

The purpose of this thesis is to design, build, test, and achieve pulsed operation of a ring-cavity erbium-doped fiber laser using carbon nanotubes as a saturable absorber. The erbium-doped fiber is characterized first, cross-sections are calculated, and the gain value is determined. Subsequently, the ring cavity is constructed and the laser is operated in the continuous wave regime. Much time is then spent trying to characterize and utilize the carbon nanotubes successfully. Many dispersions are made using multiple solvents and dispersing media, various images are taken with both scanning electron and Raman microscopy, and attempts at purification are made. Saturable …