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2014

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Articles 9331 - 9360 of 9800

Full-Text Articles in Physical Sciences and Mathematics

Sublattice-Induced Symmetry Breaking And Bandgap Formation In Graphene, Ralph A. Skomski, Peter A. Dowben, M Sky Driver, Jeffery A. Kelber Jan 2014

Sublattice-Induced Symmetry Breaking And Bandgap Formation In Graphene, Ralph A. Skomski, Peter A. Dowben, M Sky Driver, Jeffery A. Kelber

Peter Dowben Publications

A reduction of symmetry from C6v to C3v leads to the opening of a band gap in the otherwise gapless semiconductor graphene. Simple models provide a fairly complete picture of this mechanism for opening a band gap and in fact can be discussed in terms of the tight-binding approximation, accurately resolving the wave-vector space to a very high accuracy. This picture is consistent with experiments that yield a band gap due to A and B graphene-site symmetry breaking due to substrate interactions.

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Cenomanian Through Basal Coniacian Calcareous Nannofossil Biostratigraphy Of Themancos Shale Reference Section, Mesa Verde National Park, Co, Matthew J. Corbett, David K. Watkins Jan 2014

Cenomanian Through Basal Coniacian Calcareous Nannofossil Biostratigraphy Of Themancos Shale Reference Section, Mesa Verde National Park, Co, Matthew J. Corbett, David K. Watkins

Department of Earth and Atmospheric Sciences: Faculty Publications

Upper Cenomanian through lower Coniacian calcareous nannofossil biostratigraphy is integrated with macrofossil and lithostratigraphic correlations at the reference section for the Mancos Shale in Mesa Verde National Park, CO. Interpretations of key biostratigraphic events and δ13C values from bulk-rock carbonate fit well with the placement of stage boundaries by Leckie et al. (1997) and observations of nannofossil biostratigraphy in equivalent successions in the Western Interior. Tethyan nannofossil zone CC10b brackets the Cenomanian-Turonian boundary between 22.7–27.6m. Anannofossil zonal boundary between CC13 and CC14 is placed at 200.4-201m supporting the existence of an unconformity in the basal Smoky Hill Member …

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Extracting Continuum-Like Deformation And Stress From Molecular Dynamics Simulations, Lili Zhang, John Jasa, George Gazonas, Antoine Jerusalem, Mehrdad Negahban Jan 2014

Extracting Continuum-Like Deformation And Stress From Molecular Dynamics Simulations, Lili Zhang, John Jasa, George Gazonas, Antoine Jerusalem, Mehrdad Negahban

Department of Mechanical and Materials Engineering: Faculty Publications

We present methods that use results from molecular dynamics (MD) simulations to construct continuum parameters, such as deformation gradient and Cauchy stress, from all or any part of an MD system. These parameters are based on the idea of minimizing the difference between MD measures for deformation and traction and their continuum counterparts. The procedures should be applicable to non-equilibrium and inhomogeneous systems, and to any part of a system, such as a polymer chain. The resulting procedures provide methods to obtain first and higher order deformation gradients associated with any subset of the MD system, and associated expressions for …

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A Numerical Testbed For Remote Sensing Of Aerosols, And Its Demonstration For Evaluating Retrieval Synergy From A Geostationary Satellite Constellation Of Geo-Cape And Goes-R, Jun Wang, Xiaoguang Xu, Shouguo Ding, Jing Zeng, Robert Spurr, Xiong Liu, Kelly Chance, Michael I. Mishchenko Jan 2014

A Numerical Testbed For Remote Sensing Of Aerosols, And Its Demonstration For Evaluating Retrieval Synergy From A Geostationary Satellite Constellation Of Geo-Cape And Goes-R, Jun Wang, Xiaoguang Xu, Shouguo Ding, Jing Zeng, Robert Spurr, Xiong Liu, Kelly Chance, Michael I. Mishchenko

Department of Earth and Atmospheric Sciences: Faculty Publications

We present a numerical testbed for remote sensing of aerosols, together with a demonstration for evaluating retrieval synergy from a geostationary satellite constellation. The testbed combines inverse (optimal-estimation) software with a forward model containing linearized code for computing particle scattering (for both spherical and non-spherical particles). a kernel-based (land and ocean) surface bi-directional reflectance facility, and a linearized radiative transfer model for polarized radiance. Calculation of gas absorption spectra uses the HITRAN (HIgh-resolution TRANsmission molecular absorption) database of spectroscopic line parameters and other trace species cross-sections. The outputs of the testbed include not only the Stokes 4-vector elements and their …

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Prolonged Instability Prior To A Regime Shift, Trisha L. Spanbauer, Craig R. Allen, David G. Angeler, Tarsha Eason, Sherilyn C. Fritz, Ahjond S. Garmestani, Kirsty L. Nash, Jeffrey R. Stone Jan 2014

Prolonged Instability Prior To A Regime Shift, Trisha L. Spanbauer, Craig R. Allen, David G. Angeler, Tarsha Eason, Sherilyn C. Fritz, Ahjond S. Garmestani, Kirsty L. Nash, Jeffrey R. Stone

Department of Earth and Atmospheric Sciences: Faculty Publications

Regime shifts are generally defined as the point of ‘abrupt’ change in the state of a system. However, a seemingly abrupt transition can be the product of a system reorganization that has been ongoing much longer than is evident in statistical analysis of a single component of the system. Using both univariate and multivariate statistical methods, we tested a longterm high-resolution paleoecological dataset with a known change in species assemblage for a regime shift. Analysis of this dataset with Fisher Information and multivariate time series modeling showed that there was a ~2000 year period of instability prior to the regime …

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Analysis Of Vesicular Porosity In Soils Using High-Resolution X-Ray Computed Tomograpy, Judith K. Turk, Robert C. Graham Jan 2014

Analysis Of Vesicular Porosity In Soils Using High-Resolution X-Ray Computed Tomograpy, Judith K. Turk, Robert C. Graham

Conservation and Survey Division: Faculty and Staff Publications

Vesicular horizons are common at the surface of arid and semiarid soils and play a critical role in regulating infiltration. Most methods for examining pore morphology in the vesicular horizon involve physical sectioning of the sample and individual measurement of pores, which is time-consuming and provides an incomplete view of the pores. The objectives of this study were to (i) develop methods for the classification and characterization of pores in the vesicular horizon using high resolution X-ray computed tomography (HRXCT) and (ii) use these methods to examine the distribution of pores within vesic-ular peds. Three intact peds were scanned by …

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Yeast Pheromone Pathway Modeling Using Petri Nets, Stephen D. Scott, Abhishek Majumdar, Jitender S. Deogun, Steven D. Harris Jan 2014

Yeast Pheromone Pathway Modeling Using Petri Nets, Stephen D. Scott, Abhishek Majumdar, Jitender S. Deogun, Steven D. Harris

School of Computing: Conference and Workshop Papers

Background: Our environment is composed of biological components of varying magnitude. The relationships between the different biological elements can be represented as a biological network. The process of mating in S. cerevisiae is initiated by secretion of pheromone by one of the cells. Our interest lies in one particular question: how does a cell dynamically adapt the pathway to continue mating under severe environmental changes or under mutation (which might result in the loss of functionality of some proteins known to participate in the pheromone pathway). Our work attempts to answer this question. To achieve this, we first propose a …

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A Comparison Of A Campus Cluster And Open Science Grid Platforms For Protein- Guided Assembly Using Pegasus Workflow Management System, Natasha Pavlovikj, Kevin Begcy, Sairam Behera, Malachy Campbell, Harkamal Walia, Jitender S. Deogun Jan 2014

A Comparison Of A Campus Cluster And Open Science Grid Platforms For Protein- Guided Assembly Using Pegasus Workflow Management System, Natasha Pavlovikj, Kevin Begcy, Sairam Behera, Malachy Campbell, Harkamal Walia, Jitender S. Deogun

School of Computing: Conference and Workshop Papers

Scientific workflows are a useful tool for managing large and complex computational tasks. Due to its intensive resource requirements, the scientific workflows are often executed on distributed platforms, including campus clusters, grids and clouds. In this paper we build a scientific workflow for blast2cap3, the protein-guided assembly, using the Pegasus Workflow Management System (Pegasus WMS). The modularity of blast2cap3 allows us to decompose the existing serial approach on multiple tasks, some of which can be run in parallel. Afterwards, this workflow is deployed on two distributed execution platforms: Sandhills, the University of Nebraska Campus Cluster, and the Open Science …

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The Groundwater Atlas Of Lancaster County, Dana Divine Jan 2014

The Groundwater Atlas Of Lancaster County, Dana Divine

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Ferroelectric Hexagonal And Rhombic Monolayer Ice Phases, Wen-Hui Zhao, Jaeil Bai, Lan-Feng Yuan, Jinlong Yang, Xiao Cheng Zeng Jan 2014

Ferroelectric Hexagonal And Rhombic Monolayer Ice Phases, Wen-Hui Zhao, Jaeil Bai, Lan-Feng Yuan, Jinlong Yang, Xiao Cheng Zeng

Xiao Cheng Zeng Publications

Two new phases of water, the mid-density hexagonal monolayer ice and the high-density flat rhombic monolayer ice, are observed in our molecular dynamics simulations of monolayer water confined between two smooth hydrophobic walls. These are in addition to the two monolayer ices reported previously, namely, the low-density 4∙82 monolayer ice and the high-density puckered rhombic monolayer ice (HD-pRMI). Stabilities of the structures are confirmed by ab initio computation. Importantly, both new phases and the HD-pRMI are predicted to be ferroelectric. An in-plane external electric field can further stabilize these ferroelectric monolayer ices.

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Mos2/Mx2 Heterobilayers: Bandgap Engineering Via Tensile Strain Or External Electrical Field, Ning Lu, Hongyan Guo, Lei Li, Jun Dai, Lu Wang, Wai-Ning Mei, Xiaojun Wu, Xiao Cheng Zeng Jan 2014

Mos2/Mx2 Heterobilayers: Bandgap Engineering Via Tensile Strain Or External Electrical Field, Ning Lu, Hongyan Guo, Lei Li, Jun Dai, Lu Wang, Wai-Ning Mei, Xiaojun Wu, Xiao Cheng Zeng

Xiao Cheng Zeng Publications

We have performed a comprehensive first-principles study of the electronic and magnetic properties of two-dimensional (2D) transition-metal dichalcogenide (TMD) heterobilayers MX2/MoS2 (M = Mo, Cr, W, Fe, V; X = S, Se). For M = Mo, Cr, W; X = S, Se, all heterobilayers show semiconducting characteristics with an indirect bandgap with the exception of the WSe2/MoS2 heterobilayer which retains the directbandgap character of the constituent monolayer. For M = Fe, V; X = S, Se, the MX2/MoS2 heterobilayers exhibit metallic characters. Particular attention of this study has been focused on engineering the bandgap …

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Unraveling Crystalline Structure Of High-Pressure Phase Of Silicon Carbonate, Rulong Zhou, Bingyan Qu, Jun Dai, Xiao Cheng Zeng Jan 2014

Unraveling Crystalline Structure Of High-Pressure Phase Of Silicon Carbonate, Rulong Zhou, Bingyan Qu, Jun Dai, Xiao Cheng Zeng

Xiao Cheng Zeng Publications

Although CO2 and SiO2 both belong to group-IV oxides, they exhibit remarkably different bonding characteristics and phase behavior at ambient conditions. At room temperature, CO2 is a gas, whereas SiO2 is a covalent solid with rich polymorphs. A recent successful synthesis of the silicon-carbonate solid from the reaction between CO2 and SiO2 under high pressure [M. Santoro et al., Proc. Natl. Acad. Sci. U.S.A. 108, 7689 (2011)] has resolved a long-standing puzzle regarding whether a SixC1−xO2 compound between CO2 and SiO2 exists in nature. Nevertheless, the detailed …

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A Photoelectron Spectroscopy And Ab Initio Study Of The Structures And Chemical Bonding Of The B25 − Cluster, Zachary A Piazza, Ivan H. Popov, Wei-Li Li, Rhitankar Pal, Xiao Cheng Zeng, Alexander I. Boldyrev, Lai-Sheng Wang Jan 2014

A Photoelectron Spectroscopy And Ab Initio Study Of The Structures And Chemical Bonding Of The B25 − Cluster, Zachary A Piazza, Ivan H. Popov, Wei-Li Li, Rhitankar Pal, Xiao Cheng Zeng, Alexander I. Boldyrev, Lai-Sheng Wang

Xiao Cheng Zeng Publications

Photoelectron spectroscopy and ab initio calculations are used to investigate the structures and chemical bonding of the B25 − cluster. Global minimum searches reveal a dense potential energy landscape with 13 quasi-planar structures within 10 kcal/mol at the CCSD(T)/6-311+G(d) level of theory. Three quasi-planar isomers (I, II, and III) are lowest in energy and nearly degenerate at the CCSD(T) level of theory, with II and III being 0.8 and 0.9 kcal/mol higher, respectively, whereas at two density functional levels of theory isomer III is the lowest in energy (8.4 kcal/mol more stable than I at PBE0/6-311+G(2df) level). Comparison with …

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Transforming Web Tables To A Relational Database, David W. Embley, George Nagy, Sharad C. Seth Jan 2014

Transforming Web Tables To A Relational Database, David W. Embley, George Nagy, Sharad C. Seth

School of Computing: Conference and Workshop Papers

HTML tables represent a significant fraction of web data. The often complex headers of such tables are determined accurately using their indexing property. Isolated headers are factored to extract category hierarchies. Web tables are then transformed into a canonical form and imported into a relational database. The proposed processing allows for the formulation of arbitrary SQL queries over the collection of induced relational tables.

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Extended Warm Gas In The Ulirg Mrk273: Galactic Outflows And Tidal Debris, Javier Rodríguez Zaurín, Clive N. Tadhunter, David S.N. Rupke, Sylvain Veilleux, Henrik W.W. Spoon, Marco Chiaberge, Cristina Ramos Almeida, Dan Batcheldor, William B. Sparks Jan 2014

Extended Warm Gas In The Ulirg Mrk273: Galactic Outflows And Tidal Debris, Javier Rodríguez Zaurín, Clive N. Tadhunter, David S.N. Rupke, Sylvain Veilleux, Henrik W.W. Spoon, Marco Chiaberge, Cristina Ramos Almeida, Dan Batcheldor, William B. Sparks

Aerospace, Physics, and Space Science Faculty Publications

We present new HST/ACS medium-and narrow-band images and optical Isaac Newton Telescope long-slit spectra of the merging system Mrk273. The HST observations sample the [OIII]λλ4959,5007 emission from the galaxy and the nearby continuum. These data were taken as a part of a larger study of ultraluminous infrared galaxies (ULIRGs) with the aim of investigating the importance of the warm, AGN induced outflows in such objects. The HST images show that the morphologies of the extended continuum and the ionised gas emission from the galaxy are decoupled, extending almost perpendicular to each other. In particular, we detect for the first time …

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Arrakis: Atlas Of Resonance Rings As Known In The S⁴G, Sébastien Comerón, Trisha Mizusawa Jan 2014

Arrakis: Atlas Of Resonance Rings As Known In The S⁴G, Sébastien Comerón, Trisha Mizusawa

Aerospace, Physics, and Space Science Faculty Publications

Context. Resonance rings and pseudorings (here collectively called rings) are thought to be related to the gathering of material near dynamical resonances caused by non-axisymmetries in galaxy discs. This means that they are the result of secular evolution processes that redistribute material and angular momentum in discs. Studying them may give clues on the formation and growth of bars and other disc non-axisymmetries. Aims. Our aims are to produce a catalogue and an atlas of the rings detected in the Spitzer Survey of Stellar Structure in Galaxies (S⁴G) and to conduct a statistical study of the data in the catalogue. …

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Emission Lines Properties Of The Radio-Loud Quasar Lamost J1131+3114, Zhixin Shi, Georges Comte, Ali L. Luo, Tuehong H. Zhao, Jingkun K. Zhao, T D. Oswalt, Fuchao C. Wu Jan 2014

Emission Lines Properties Of The Radio-Loud Quasar Lamost J1131+3114, Zhixin Shi, Georges Comte, Ali L. Luo, Tuehong H. Zhao, Jingkun K. Zhao, T D. Oswalt, Fuchao C. Wu

Aerospace, Physics, and Space Science Faculty Publications

The radio-loud quasar LAMOST J1131+3114 (Ton 580, B2 1128+315), showing asymmetrical profile in Hβ and [O III] lines, has been selected from the LAMOST Pilot Survey for further study. We present an analysis of its emission lines by means of multiple Gaussian fitting, performed on LAMOST, Apache Point Observatory, and archival spectra. The broad line region, with an Hβ line of FWHM ~ 4000 km sˉ¹ has been fit with a double Gaussian, one of which is very broad and redshifted from the reference frame. The object is a likely Population B quasar. The [O III] λλ4959,5007 lines profiles of …

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Modulated X-Ray Emission Of The Magnetic O8.5v-Star Tr16-22, Yaël Nazé, Gregg A. Wade, Véronique Petit Jan 2014

Modulated X-Ray Emission Of The Magnetic O8.5v-Star Tr16-22, Yaël Nazé, Gregg A. Wade, Véronique Petit

Aerospace, Physics, and Space Science Faculty Publications

Using an extensive X-ray dataset, we analyzed the X-ray emission of the massive O-star Tr16-22, which was recently found to be magnetic. Its bright X-ray emission is found to be modulated with a 54d period. This timescale should represent the rotational timescale of the star, as it does for other magnetic massive stars. In parallel, new spectropolarimetric data confirm the published magnetic detection.

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Embedded Star Formation In S4g Galaxy Dust Lanes, Debra M. Elmegreen, Trisha Mizusawa Jan 2014

Embedded Star Formation In S4g Galaxy Dust Lanes, Debra M. Elmegreen, Trisha Mizusawa

Aerospace, Physics, and Space Science Faculty Publications

Star-forming regions that are visible at 3.6 μm and Hα but not in the u, g, r, i, z bands of the Sloan Digital Sky Survey are measured in five nearby spiral galaxies to find extinctions averaging ∼3.8 mag and stellar masses averaging ∼5 × 104 M ⊙. These regions are apparently young star complexes embedded in dark filamentary shock fronts connected with spiral arms. The associated cloud masses are ∼10 7 M ⊙. The conditions required to make such complexes are explored, including gravitational instabilities in spiral-shocked gas and compression of incident clouds. We find that instabilities are too …

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An Analytical Approach For Calculating Energy Spectra Of Relativistic Runaway Electron Avalanches In Air, Eric S. Crame, Joseph R. Dwyer, Shahab Arabshahi, Igor B. Vodopiyanov, Ningyu Liu, Hamid K. Rassoul Jan 2014

An Analytical Approach For Calculating Energy Spectra Of Relativistic Runaway Electron Avalanches In Air, Eric S. Crame, Joseph R. Dwyer, Shahab Arabshahi, Igor B. Vodopiyanov, Ningyu Liu, Hamid K. Rassoul

Aerospace, Physics, and Space Science Faculty Publications

Simplified equations describing the transport and energy spectrum of runaway electrons are derived from the basic kinematics of the continuity equations. These equations are useful in modeling the energy distribution of energetic electrons in strong electric fields, such as those found inside thunderstorms. Dwyer and Babich (2011) investigated the generation of low-energy electrons in relativistic runaway electron avalanches. The paper also developed simple analytical expressions to describe the detailed physics of Monte Carlo simulations of relativistic runaway electrons in air. In the current work, the energy spectra of the runaway electron population are studied in detail. Dependence of electron avalanche …

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Mvapack: A Complete Data Handling Package For Nmr Metabolomics, Bradley Worley, Robert Powers Jan 2014

Mvapack: A Complete Data Handling Package For Nmr Metabolomics, Bradley Worley, Robert Powers

Robert Powers Publications

Data handling in the field of NMR metabolomics has historically been reliant on either in-house mathematical routines or long chains of expensive commercial software. Thus, while the relatively simple biochemical protocols of metabolomics maintain a low barrier to entry, new practitioners of metabolomics experiments are forced to either purchase expensive software packages or craft their own data handling solutions from scratch. This inevitably complicates the standardization and communication of data handling protocols in the field. We report a newly developed open-source platform for complete NMR metabolomics data handling, MVAPACK, and describe its application on an example metabolic fingerprinting data set.

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A Depth Refugium From Catastrophic Coral Bleaching Prevents Regional Extinction, Tyler B. Smith, Peter W. Glynn, Juan L. Maté, Lauren T. Toth, Joanna Gyory Jan 2014

A Depth Refugium From Catastrophic Coral Bleaching Prevents Regional Extinction, Tyler B. Smith, Peter W. Glynn, Juan L. Maté, Lauren T. Toth, Joanna Gyory

Ocean Engineering and Marine Sciences Faculty Publications

Species intolerant of changing climate might avoid extinction within refugia buffered from extreme conditions. Refugia have been observed in the fossil record but are not well documented or understood on ecological time scales. Using a 37-year record from the eastern Pacific across the two most severe El Nin˜ o events on record (1982–1983 and 1997– 1998) we show how an exceptionally thermally sensitive reef-building hydrocoral, Millepora intricata, twice survived catastrophic bleaching in a deeper-water refuge (.11 m depth). During both events, M. intricata was extirpated across its range in shallow water, but showed recovery within several years, while two other …

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Comparing Biofouling Control Treatments For Use On Aquaculture Nets, Geoffrey Swain, Nagahiko Shinjo Jan 2014

Comparing Biofouling Control Treatments For Use On Aquaculture Nets, Geoffrey Swain, Nagahiko Shinjo

Ocean Engineering and Marine Sciences Faculty Publications

Test panels comprised of uncoated, copper coated and silicone coated 7/8'' (22 mm) mesh knitted nylon net were evaluated to compare their properties and the effectiveness to prevent biofouling. This paper describes test procedures that were developed to quantify the performance in terms of antifouling, cleanability, drag and cost. The copper treatment was the most effective at controlling fouling, however, the silicone treated nets were the easiest to clean. The drag forces on the net were a function of twine diameter, twine roughness and fouling. After immersion, the uncoated nets had the most drag followed by the silicone and copper …

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Organic Ferroelectric Evaporator With Substrate Cooling And In Situ Transport Capabilities, Keith Foreman, C. Labedz, M. Shearer, Shireen Adenwalla Jan 2014

Organic Ferroelectric Evaporator With Substrate Cooling And In Situ Transport Capabilities, Keith Foreman, C. Labedz, M. Shearer, Shireen Adenwalla

Shireen Adenwalla Papers

We report on the design, operation, and performance of a thermal evaporation chamber capable of evaporating organic thin films. Organic thin films are employed in a diverse range of devices and can provide insight into fundamental physical phenomena. However, growing organic thin films is often challenging and requires very specific deposition parameters. The chamber presented here is capable of cooling sample substrates to temperatures below 130 K and allows for the detachment of the sample from the cooling stage and in situ transport. This permits the use of multiple deposition techniques in separate, but connected, deposition chambers without breaking vacuum …

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Assessing Satellite-Based Start-Of-Season Trends In The U.S High Plains, Rezaul Mahmood Jan 2014

Assessing Satellite-Based Start-Of-Season Trends In The U.S High Plains, Rezaul Mahmood

School of Natural Resources: Faculty Publications

No abstract provided.

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Practical Aspects Of Modern And Future Permanent Magnets, R.W. Mccallum, L. H. Lewis, Ralph Skomski, M. J. Kramer, I. E. Anderson Jan 2014

Practical Aspects Of Modern And Future Permanent Magnets, R.W. Mccallum, L. H. Lewis, Ralph Skomski, M. J. Kramer, I. E. Anderson

Ralph Skomski Publications

The mandate to reduce greenhouse gases will require highly efficient electric machines for both power generation and traction motor applications. Although permanent magnet electric machines utilizing Nd2Fe14B-based magnets provide obvious power-to-weight advantages over induction machines, the limited availability and high price of the rare earth (RE) metals make these machines less favorable. Of particular concern is the cost and supply criticality of Dy, a key RE element that is required to improve the high-temperature performance of Nd-based magnetic alloys for use in generators and traction motors. Alternatives to RE-based alloys do exist, but they currently lack the energy density necessary …

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Downhill Domination In Graphs, Teresa W. Haynes, Stephen T. Hedetniemi, Jessie D. Jamieson, William B. Jamieson Jan 2014

Downhill Domination In Graphs, Teresa W. Haynes, Stephen T. Hedetniemi, Jessie D. Jamieson, William B. Jamieson

Department of Mathematics: Faculty Publications

A path π = (v1, v2, . . . , vk+1) iun a graph G = (V, E) is a downhill path if for every i, 1 ≤ i ≤ k, deg(vi) ≥ deg(vi+1), where deg(vi) denotes the degree of vertex vi ∈ V. The downhill domination number equals the minimum cardinality of a set S ⊆ V having the property that every vertex v ∈ V lies on a downhill path originating from some vertex in S …

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Nutrient Composition Of Selected Traditional United States Northern Plains Native American Plant Foods, Katherine M. Phillips, Pamela R. Pehrsson, Wanda W. Agnew, Angela J. Scheett, Jennifer R. Follett, Henry C. Lukaski, Kristine Y. Patterson Jan 2014

Nutrient Composition Of Selected Traditional United States Northern Plains Native American Plant Foods, Katherine M. Phillips, Pamela R. Pehrsson, Wanda W. Agnew, Angela J. Scheett, Jennifer R. Follett, Henry C. Lukaski, Kristine Y. Patterson

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Ten wild plants (cattail broad leaf shoots, chokecherries, beaked hazelnuts, lambsquarters, plains prickly pear, prairie turnips, stinging nettles, wild plums, raspberries, and rose hips) from three Native American reservations in North Dakota were analyzed to expand composition information of traditional foraged plants. Proximates, dietary fiber (DF), vitamins, minerals, carotenoids, and folate vitamers were assayed using standard methods and reference materials. Per serving, all were rich in Mn (100–2808 mg). Several provided >10% DRI of Fe (cattail shoots, steamed lambsquarters, and prairie turnips), Ca (steamed lambsquarters, prickly pear, and prairie turnips), Mg (cattail shoots, lambsquarters, prickly pear, and prairie turnips), vitamins …

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Long-Range Propagation, Interaction, And Dissipation Of Small-Scale Gravity Waves In The Mesosphere And Lower Thermosphere, Christopher J. Heale Jan 2014

Long-Range Propagation, Interaction, And Dissipation Of Small-Scale Gravity Waves In The Mesosphere And Lower Thermosphere, Christopher J. Heale

Doctoral Dissertations and Master's Theses

A 2-D nonlinear, compressible numerical model [Snively and Pasko, 2008] is used in conjunction with ray-theory to investigate the long-range propagation, dissipation and interaction of small-scale gravity waves in the Mesosphere and Lower Thermosphere (MLT) region. The research in this thesis is made up of three distinct studies which build upon each other. The first investigates the thermospheric dissipation of three gravity wave packets representing: (1) A quasi-monochromatic packet, (2) A monochromatic, steady state wave, and (3) A spectrally broad packet, as well as an initial condition specified packet. It is found that dissipation due to molecular viscosity and …

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Robust Preconditioners For The High-Contrast Elliptic Partial Differential Equations, Zuhal Unlu Jan 2014

Robust Preconditioners For The High-Contrast Elliptic Partial Differential Equations, Zuhal Unlu

LSU Doctoral Dissertations

In this thesis, we discuss a robust preconditioner (the AGKS preconditioner) for solving linear systems arising from approximations of partial differential equations (PDEs) with high-contrast coefficients. The problems considered here include the standard second and higher order elliptic PDEs such as high-contrast diffusion equation, Stokes' equation and biharmonic-plate equation. The goal of this study is the development of robust and parallelizable preconditioners that can easily be integrated to treat large configurations. The construction of the preconditioner consists of two phases. The first one is an algebraic phase which partitions the degrees of freedom into high and low permeability regions which …

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