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Electric Breakdown Of Longitudinally Shocked Pb(Zr₀.₅₂Ti₀.₄₈)O₃ Ceramics, S. I. Shkuratov, E. F. Talantsev, Jason Baird Jul 2011

Electric Breakdown Of Longitudinally Shocked Pb(Zr₀.₅₂Ti₀.₄₈)O₃ Ceramics, S. I. Shkuratov, E. F. Talantsev, Jason Baird

Mining Engineering Faculty Research & Creative Works

Electric breakdown of longitudinally-shock-compressed Pb(Zr₀.₅₂Ti₀.₄₈)O₃ (PZT 52/48) ferroelectric ceramics was experimentally investigated. It was found that a dependence of breakdown field strength, Eg, of shocked ferroelectrics on the thickness of the element, d, ranging from 0.65 to 6.5 mm is described by the Eg (d) = γ  · d-w law that describes the breakdown of dielectrics at ambient conditions. It follows from the experimental results that the tunnel effect is a dominant mechanism of injection of prime electrons in the shocked ferroelectric elements. It was demonstrated that electric breakdown causes significant energy losses in miniature autonomous …

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Bis[2-(1h-Imidazol-2-Yl-Κn³)-1h-Imidazol-3-Ium]Silver(I) Trinitrate, Shelonda R. Finch, J. P. Harper, Amitava Choudhury, Ekkehard Sinn, Harvest L. Collier Jul 2011

Bis[2-(1h-Imidazol-2-Yl-Κn³)-1h-Imidazol-3-Ium]Silver(I) Trinitrate, Shelonda R. Finch, J. P. Harper, Amitava Choudhury, Ekkehard Sinn, Harvest L. Collier

Chemistry Faculty Research & Creative Works

The synthesis of the title salt, [Ag(C 6H 7N 4) 2](NO 3) 3, was carried out employing a 1:2 molar ratio of 2,2'-biimidazole and silver nitrate respectively. The cation has crystallographically-imposed C2 symmetry with the metal atom in an almost linear coordination environment [N - Ag - N = 177.01 (17)°]. The crystal structure displays N - H⋯O and C - H⋯O hydrogen-bonding interactions.

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Relativistic Reduced-Mass And Recoil Corrections To Vacuum Polarization In Muonic Hydrogen, Muonic Deuterium, And Muonic Helium Ions, Ulrich D. Jentschura Jul 2011

Relativistic Reduced-Mass And Recoil Corrections To Vacuum Polarization In Muonic Hydrogen, Muonic Deuterium, And Muonic Helium Ions, Ulrich D. Jentschura

Physics Faculty Research & Creative Works

The reduced-mass dependence of relativistic and radiative effects in simple muonic bound systems is investigated. The spin-dependent nuclear recoil correction of order (Zα)4μ3/m2N is evaluated for muonic hydrogen and deuterium and muonic helium ions (μ is the reduced mass and mN is the nuclear mass). Relativistic corrections to vacuum polarization of order α(Zα)4μ are calculated, with a full account of the reduced-mass dependence. The results shift theoretical predictions. The radiative-recoil correction to vacuum polarization of order α(Zα)5-ln2(Zα) μ2/mN is obtained in leading logarithmic approximation. …

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Classical Analogue Of Electromagnetically Induced Transparency With A Metal-Superconductor Hybrid Metamaterial, Cihan Kurter, Philippe Tassin, Lei Zhang, Thomas Koschny, Alexander P. Zhuravel, Alexey V. Ustinov, Steven Mark Anlage, Costas M. Soukoulis Jul 2011

Classical Analogue Of Electromagnetically Induced Transparency With A Metal-Superconductor Hybrid Metamaterial, Cihan Kurter, Philippe Tassin, Lei Zhang, Thomas Koschny, Alexander P. Zhuravel, Alexey V. Ustinov, Steven Mark Anlage, Costas M. Soukoulis

Physics Faculty Research & Creative Works

Metamaterials are engineered materials composed of small electrical circuits producing novel interactions with electromagnetic waves. Recently, a new class of metamaterials has been created to mimic the behavior of media displaying electromagnetically induced transparency (EIT). Here we introduce a planar EIT metamaterial that creates a very large loss contrast between the dark and radiative resonators by employing a superconducting Nb film in the dark element and a normal-metal Au film in the radiative element. Below the critical temperature of Nb, the resistance contrast opens up a transparency window along with a large enhancement in group delay, enabling a significant slowdown …

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A Slurry Consolidation Approach To Reconstitute Low-Plasticity Silt Specimens For Laboratory Triaxial Testing, Shuying Wang, Ronaldo Luna, Richard Wesley Stephenson Jul 2011

A Slurry Consolidation Approach To Reconstitute Low-Plasticity Silt Specimens For Laboratory Triaxial Testing, Shuying Wang, Ronaldo Luna, Richard Wesley Stephenson

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Silt Specimen Reconstitution using a Slurry Consolidation Approach is Commonly Used for Laboratory Testing. This Paper Presents a New Slurry Consolidation Approach to Reconstitute Silt Specimens for Use in Triaxial Testing. Silt Specimens Were Reconstituted in a Split Vacuum Mold Mounted on a Special Experimental Setup. the Uniformity of the Reconstituted Specimens Was Verified by Measuring the Water Content and Grain Size Distribution throughout the Specimens. the Testing Program Was Expedited using a Special Sample Handling Technique to Move the Specimen from the Special Experimental Setup to the Triaxial Chamber Base Platen. the Handling Process Did Not Disturb the Specimens …

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Reliability-Based Turbo Detection, Jun Tao, Jingxian Wu, Yahong Rosa Zheng Jul 2011

Reliability-Based Turbo Detection, Jun Tao, Jingxian Wu, Yahong Rosa Zheng

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes a reliability-Based turbo detection scheme for multiple-input multiple-output (MIMO) systems with frequency-selective fading. the proposed scheme performs iterative successive soft interference cancellation (SSIC) with a block decision-feedback equalizer (BDFE). to minimize the negative impacts of error propagation in SSIC, we propose a new group-wise reliability-Based ordering scheme, where neighboring symbols that severely interfere with each other are clustered into the same group, and for each group, more "reliable" symbols are detected before less "reliable" ones. the symbol reliability is measured by using the symbol a priori probability, which is a unique byproduct of the turbo detection and …

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Localization Of Objects Using Stochastic Tunneling, Mohammed Rana Basheer, Sarangapani Jagannathan Jun 2011

Localization Of Objects Using Stochastic Tunneling, Mohammed Rana Basheer, Sarangapani Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a novel wireless localization scheme in the three-dimensional domain that employs stochastic optimization with tunneling transformation to recursively estimate the location of wireless tags in a network from pair wise signal strength measurements. Spatially co-located wireless tags, receiving signals from a common transmitter, exhibit correlation in their Received Signal Strength Indicator (RSSI) values. Hence in a network of wireless tags, with pair wise correlation coefficients available, posterior distribution of the unknown tag separation is used to relatively localize them using maximum a posteriori (MAP) Estimator. However, due to the non-convex/non-tractable nature of this posterior distribution, deterministic optimization …

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Spectrum Management For Wireless Networks Using Adaptive Control And Game Theory, Swagoto Roy, Liuju Wu, Macie Zawodniok Jun 2011

Spectrum Management For Wireless Networks Using Adaptive Control And Game Theory, Swagoto Roy, Liuju Wu, Macie Zawodniok

Electrical and Computer Engineering Faculty Research & Creative Works

Radio frequency spectrum in wireless communication is a common resource shared by all collocated devices. Most spectrum management schemes rely on a centralized base station-receiver station relaying architecture. in contrast, infrastructure-less systems including wireless ad hoc networks require a scalable, distributed methodology. Moreover, the access has to be coordinated among the nodes in the network in the aspects which include power and rate adaptation. the challenge is to find an optimal tradeoff between such parameters not only for a particular link but also for an entire multi-hop network. Several existing schemes address power, throughput and Signal-to-Interference ratio (SIR) control on …

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Soft-Decision Feedback Turbo Equalization For Multiple Antenna Systems With Multilevel Modulations, Amirhossein Rafati, Huang Lou, Chengshan Xiao Jun 2011

Soft-Decision Feedback Turbo Equalization For Multiple Antenna Systems With Multilevel Modulations, Amirhossein Rafati, Huang Lou, Chengshan Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

Many communication systems today encounter the problem of data transmission over a channel with inter-symbol interference (ISI). the purpose of this paper is to develop a low-complexity, iterative soft-decision feedback equalization (SDFE) receiver for severe, frequency selective ISI channels. the proposed SDFE algorithm offers a novel approach to combat error propagation. in addition, its computational complexity grows only linearly with the number of equalizer coefficients, compared to the quadratic complexity of minimum mean square error-Based linear turbo equalizer with time-varying coefficients. Performance of the proposed detection scheme is verified through simulations using different signal constellations. Simulation results show that our …

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Dsg-N²: A Group-Based Social Routing Algorithm, Roy Cabaniss, James M. Bridges, Andrew Wilson, Sanjay Madria Jun 2011

Dsg-N²: A Group-Based Social Routing Algorithm, Roy Cabaniss, James M. Bridges, Andrew Wilson, Sanjay Madria

Computer Science Faculty Research & Creative Works

Devices in a mobile ad-hoc environment can follow different movement patterns based on the application environment. Some environments, such as mass transit systems, follow regular and predictable patterns. Others, such as an aerial monitoring network, generally follow random paths. Optimal routing schemes tend to take advantage of information regarding movement patterns available in social interaction domains. in a social environment like wildlife tracking or monitoring socio-human interactions, the devices and/or users will follow regular contact habits, tending to encounter social groups in which they participate. in this paper, by dynamically identifying these groups, the patterns are used to speed routing …

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Multi-Hop Framework For Battery-Less Devices Using Passive Rf Communication, Vikram Reddy Surendra, Maciej Jan Zawodniok Jun 2011

Multi-Hop Framework For Battery-Less Devices Using Passive Rf Communication, Vikram Reddy Surendra, Maciej Jan Zawodniok

Electrical and Computer Engineering Faculty Research & Creative Works

Typical wireless multi-hop networks employ active communication where RF signal is actively generated by a sending node. in contrast, backscatter communication modulates backscattered RF signal that requires significantly less energy to operate than the active one. This paper proposes a novel, multi-hop architecture for such backscatter-Based communication that is not currently present in the literature. Such a system consists of a powerful reader and small, battery-less nodes. the reader generates the original RF signal, while the passive devices backscatter this signal to communicate among themselves thus enabling multihop transmission from far-away nodes. the paper presents the generic analysis of the …

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Vibrational Spectroscopy Of N-Methyliminodiacetic Acid (Mida)-Protected Boronate Ester: Examination Of The B-N Dative Bond, Dana N. Reinemann, Ashley M. Wright, Jonathan D. Wolfe, Gregory S. Tschumper, Nathan I. Hammer Jun 2011

Vibrational Spectroscopy Of N-Methyliminodiacetic Acid (Mida)-Protected Boronate Ester: Examination Of The B-N Dative Bond, Dana N. Reinemann, Ashley M. Wright, Jonathan D. Wolfe, Gregory S. Tschumper, Nathan I. Hammer

Chemistry Faculty Research & Creative Works

N-Methyliminodiacetic acid (MIDA)-protected boronate esters are a new class of reagents that offer great promise in iterative Suzuki-Miyaura cross-coupling reactions. Compared to earlier reagents, MIDA esters are easily handled and are benchtop stable under air indefinitely. The success of this new species is tied to its unique molecular architecture. Compared to the simpler B-N containing molecules ammonia borane and trimethylamine borane, MIDA esters are much larger, and the sp3 hybridized boron atom is secured by two five membered rings, making this molecular class stable for spectroscopic study. Here, we present infrared, Raman, and surface enhanced Raman (SERS) spectra of methylboronic …

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An Argument For The Importance Of Material Property Characterization Of Hydrogels, J. M. Zuidema, R. J. Gilbert Jun 2011

An Argument For The Importance Of Material Property Characterization Of Hydrogels, J. M. Zuidema, R. J. Gilbert

Chemical and Biochemical Engineering Faculty Research & Creative Works

Hydrogels are being fabricated for use in many tissue engineering applications. In order to advance the field, material properties must be characterized to determine the most desirable attributes. The data presented shows the importance of both surface charge and mechanical properties on dorsal root ganglia neurite extension. © 2011 IEEE.

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Faculty Senate Minutes June 16, 2011, Missouri University Of Science And Technology Faculty Senate Jun 2011

Faculty Senate Minutes June 16, 2011, Missouri University Of Science And Technology Faculty Senate

Minutes & Agendas

No abstract provided.

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Aluminium-Free Glass Polyalkenoate Spinal Cements, A. W. Wren, N. M. Cummins, Mark R. Towler Jun 2011

Aluminium-Free Glass Polyalkenoate Spinal Cements, A. W. Wren, N. M. Cummins, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Addition of Yitanium increased the Wt & St and the sf strength of these cements compared to the control (BT 101). © 2011 IEEE.

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Fabrication And Characterization Of A Hydrogel Containing Electrospun Fibers, C. J. Rivet, R. J. Gilbert Jun 2011

Fabrication And Characterization Of A Hydrogel Containing Electrospun Fibers, C. J. Rivet, R. J. Gilbert

Chemical and Biochemical Engineering Faculty Research & Creative Works

Electro spun an fibers hydrogels are two focal points of research within the biomaterial's community. The electrospinning process allows for fabrication of nanoscale, aligned topography and has been shown to direct cellular migration and outgrowth. Hydrogels exhibit benefits over traditional, rigid scaffolds in that they are injectable and can be tailored to mimic the mechanical properties of the surrounding tissue. Although both electro spun fibers and hydrogels display favorable characteristics for biomedical applications in vitro, there in vivo benefits are limited due to inherent deficiencies Therefore, to advance the field of biomaterials research, a composite material containing electro spun fibers …

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The Effect Of Adding Organic Polymers To Ca-Sr-Zn-Si Glass Polyalkenoate Cement, A. Coughlan, N. M. Cummins, A. W. Wren, Mark R. Towler Jun 2011

The Effect Of Adding Organic Polymers To Ca-Sr-Zn-Si Glass Polyalkenoate Cement, A. Coughlan, N. M. Cummins, A. W. Wren, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

To conclude, the addition of polymers to GPCs resulted in little change to the Tw and Ts, however the compressive strength was found to decrease slightly. ASAP tests revealed that the cements may undergo some structural changes as a result of these additions. In the future perhaps the addition of organic polymers suspended in the liquid phase as part of the cement may yield improved results in this type of study. © 2011 IEEE.

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Fabrication And Analysis Of Variable Density Poly-(L)-Lactic Acid Fiber Scaffolds, N. W. Zaccor, C. J. Rivet, R. J. Gilbert Jun 2011

Fabrication And Analysis Of Variable Density Poly-(L)-Lactic Acid Fiber Scaffolds, N. W. Zaccor, C. J. Rivet, R. J. Gilbert

Chemical and Biochemical Engineering Faculty Research & Creative Works

Poly-L-lactic acid (PLLA) is an extensively studied synthetic polymer that has demonstrated utility as a scaffolding material. A common technique for the fabrication of PLLA scaffolds is electrospinning. The purpose of the present material study was to assess whether an electrospinning process could produce consistent and uniform PLLA scaffold densities. An 8% PLLA solution was made using a 1:1 chloroform: dichloromethane solution and was then run through an electrospinning apparatus. Samples were spun onto 4% PLLA films for 2- or 20-min. Scanning electron microscopy (SEM) was used for imaging the scaffolds. A nine-measurement data set was used for the assessment …

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Aligned, Electrospun Topography For Use With External Stimulus Systems, S. G. Quallich, C. J. Rivet, R. J. Gilbert Jun 2011

Aligned, Electrospun Topography For Use With External Stimulus Systems, S. G. Quallich, C. J. Rivet, R. J. Gilbert

Chemical and Biochemical Engineering Faculty Research & Creative Works

Variations in fiber density, diameter, and orientation can be used to direct cell migration and guide neurite growth. The characterization of electro spun fibers is essential prior to conducting further research that utilizes electro spun scaffolds to control the magnitude and direction of cell migration and neurite growth. The goal of this study is to create highly aligned, electro spun fibers on poly-L-lactic acid (PLLA) films in parallel and perpendicular orientations to the long axis of rectangular cover slips. Fibers were electro spun into scaffolds and scanning electron microscopy (SEM) was used to characterize fiber density and orientation. The construction …

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Using Cerebrospinal Fluid For In Situ Fabrication Of Injectable Alginate Hydrogels For Spinal Cord Repair, C. A. Mckay, R. J. Gilbert Jun 2011

Using Cerebrospinal Fluid For In Situ Fabrication Of Injectable Alginate Hydrogels For Spinal Cord Repair, C. A. Mckay, R. J. Gilbert

Chemical and Biochemical Engineering Faculty Research & Creative Works

Severe mechanical trauma of the spinal cord induces a secondary injury response that contributes to post injury cell death and the formation of barriers inhibitory to neuronal regeneration. It is believed that engineered scaffolds produce favorable results when they mimic the properties of the t issue that they are aiming to replicate. Alginate hydrogels have been shown to be beneficial in a number of biomaterial applications and this study shows that alginate hydrogels formed in the presence of an artificial cerebrospinal fluid are able to form hydrogels with mechanical properties similar to those exhibited by neural tissue in the CNS. …

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Decreasing The Gelation Time Of Fibrin Hydrogels, C. D. Johnson, J. Zudiema, R. J. Gilbert Jun 2011

Decreasing The Gelation Time Of Fibrin Hydrogels, C. D. Johnson, J. Zudiema, R. J. Gilbert

Chemical and Biochemical Engineering Faculty Research & Creative Works

Spinal cord injury (SCI) is a debilitating problem that often results in paraplegia or quadriplegia. Fibrin hydrogels can be injected into the injured cavity and fill the irregular space. Current techniques require 60 minutes to form a hydrogel. The purpose of this study was to design a fibrin biomaterial that would solidify at a faster rate. By augmenting the existing fabrication procedure, a novel biomaterial was created that formed in 5-7 minutes but lost much of its mechanical stability. Further studies will be performed to improve the mechanical properties while maintaining the faster rate of formation observed here. © 2011 …

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Effect Of Molecular Film Thickness On Thermal Conduction Across Solid-Film Interfaces, Zhi Liang, Hai-Lung Tsai Jun 2011

Effect Of Molecular Film Thickness On Thermal Conduction Across Solid-Film Interfaces, Zhi Liang, Hai-Lung Tsai

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The Brownian Motion and Aggregation of Particles in Nanofluids Often Lead to the Formation of Solid-Film-Solid Structures. the Molecular Thin Film Confined between Nanoparticles May Have Non-Negligible Effects on Thermal Conduction among Nanoparticles. using Nonequilibrium Molecular Dynamics Simulations, We Study Thermal Conduction Across the Ag Particle-Ar Thin-Film Interface. If the Film Contains Only One Molecular Layer, We Find that the Solid-Film Interfacial Thermal Resistance RSF is About 1 Order of Magnitude Smaller Than the Solid-Liquid (Bulk) Interfacial Thermal Resistance RSL. If There Are Two or More Molecular Layers in the Film, It is Shown that RSF Increases Rapidly toward RSL …

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Temperature Control Device With A Flexible Temperature Control Surface, Phil D. Belgrader, Christopher G. Cooney, Robert D. Doebler, Anna D. Hickerson, Bruce D. Irvine, Ali D. Nadim, James D. Sterling, Reza Miraghale Jun 2011

Temperature Control Device With A Flexible Temperature Control Surface, Phil D. Belgrader, Christopher G. Cooney, Robert D. Doebler, Anna D. Hickerson, Bruce D. Irvine, Ali D. Nadim, James D. Sterling, Reza Miraghale

Business and Information Technology Faculty Research & Creative Works

A device for controlling temperature in a reaction chamber is disclosed. The device comprises: a bladder assembly comprising a housing dimensioned to hold a reaction chamber disposed within an interior Volume of the housing; and a first temperature-control bladder disposed within the housing, the first temperature-control bladder is configured to receive a temperature-control fluid and comprises a flexible, heat conductive Surface that comes in contact with at least a portion of an exterior surface of the reaction chamber after receiving the temperature-control fluid. Also disclosed are a bladder thermal cycler, a temperature-control bladder assembly and methods for producing a thermal …

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A Novel Implementation Of Discrete Complex Image Method For Layered Medium Green's Function, Yongpin P. Chen, Weng Cho Chew, Lijun Jiang Jun 2011

A Novel Implementation Of Discrete Complex Image Method For Layered Medium Green's Function, Yongpin P. Chen, Weng Cho Chew, Lijun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

A novel implementation of discrete complex image method (DCIM) based on the Sommmerfeld branch cut is proposed to accurately capture the far-field behavior of the layered medium Green's function as a complement to the traditional DCIM. By contour deformation, the Green's function can be naturally decomposed into branch-cut integration (radiation modes) and pole contributions (guided modes). For branch-cut integration, matrix pencil method is applied, and the alternative Sommerfeld identity in terms of kz integration is utilized to get a closed-form solution. The guided modes are accounted for with a pole-searching algorithm. Both one-branch-cut and two-branch-cut cases are studied. Several numerical …

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Distant Positioning Of Proteasomal Proteolysis Relative To Actively Transcribed Genes, Andrea Scharf, Petar N. Grozdanov, Roman Veith, Ulrich Kubitscheck, U. Thomas Meier, Anna Von Mikecz Jun 2011

Distant Positioning Of Proteasomal Proteolysis Relative To Actively Transcribed Genes, Andrea Scharf, Petar N. Grozdanov, Roman Veith, Ulrich Kubitscheck, U. Thomas Meier, Anna Von Mikecz

Biological Sciences Faculty Research & Creative Works

While it is widely acknowledged that the ubiquitin-proteasome system plays an important role in transcription, little is known concerning the mechanistic basis, in particular the spatial organization of proteasome-dependent proteolysis at the transcription site. Here, we show that proteasomal activity and tetraubiquitinated proteins concentrate to nucleoplasmic microenvironments in the euchromatin. Such proteolytic domains are immobile and distinctly positioned in relation to transcriptional processes. Analysis of gene arrays and early genes in Caenorhabditis elegans embryos reveals that proteasomes and proteasomal activity are distantly located relative to transcriptionally active genes. In contrast, transcriptional inhibition generally induces local overlap of proteolytic microdomains with …

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Large Kinetic Asymmetry In The Metal-Insulator Transition Nucleated At Localized And Extended Defects, W. Fan, Jinbo Cao, J. Seidel, Yijia Gu, J. W. Yim, For Full List Of Authors, See Publisher's Website. Jun 2011

Large Kinetic Asymmetry In The Metal-Insulator Transition Nucleated At Localized And Extended Defects, W. Fan, Jinbo Cao, J. Seidel, Yijia Gu, J. W. Yim, For Full List Of Authors, See Publisher's Website.

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Superheating and supercooling effects are characteristic kinetic processes in first-order phase transitions, and asymmetry between them is widely observed. In materials where electronic and structural degrees of freedom are coupled, a wide, asymmetric hysteresis may occur in the transition between electronic phases. Structural defects are known to seed heterogeneous nucleation of the phase transition, hence reduce the degree of superheating and supercooling. Here we show that in the metal-insulator transition of single-crystal VO 2, a large kinetic asymmetry arises from the distinct spatial extension and distribution of two basic types of crystal defects: point defects and twin walls. Nanometer-thick twin …

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Design Optimization Of Gaas Betavoltaic Batteries, Haiyanag Chen, Lan Jiang, Xuyuan Chen Jun 2011

Design Optimization Of Gaas Betavoltaic Batteries, Haiyanag Chen, Lan Jiang, Xuyuan Chen

Mechanical and Aerospace Engineering Faculty Research & Creative Works

GaAs junctions are designed and fabricated for beta voltaic batteries. the design is optimized according to the characteristics of GaAs interface states and the diffusion length in the depletion region of GaAs carriers. under an illumination of 10 mCi cm-263Ni, the open circuit voltage of the optimized batteries is about ∼0.3 V. It is found that the GaAs interface states induce depletion layers on P-type GaAs surfaces. the depletion layer along the P+PN+ junction edge isolates the perimeter surface from the bulk junction, which tends to significantly reduce the battery dark current and leads to a high open circuit voltage. …

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Crustal Structure And Evolution Beneath The Colorado Plateau And The Southern Basin And Range Province: Results From Receiver Function And Gravity Studies, Lamuail Bashir, Stephen S. Gao, Kelly H. Liu, Kevin Lee Mickus Jun 2011

Crustal Structure And Evolution Beneath The Colorado Plateau And The Southern Basin And Range Province: Results From Receiver Function And Gravity Studies, Lamuail Bashir, Stephen S. Gao, Kelly H. Liu, Kevin Lee Mickus

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Over the past several decades, contrasting models have been proposed for the physical and chemical processes responsible for the uplift and long-term stability of the Colorado Plateau (CP) and crustal thinning beneath the Basin and Range Province (BRP) in the southwestern United States. Here we provide new constraints on the models by modeling gravity anomalies and by systematically analyzing over 15,500 P-to-S receiver functions recorded at 72 USArray and other broadband seismic stations on the southwestern CP and the southern BRP. Our results reveal that the BRP is characterized by a thin crust (28.2 ± 0.5 km), a mean V …

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Young-Type Interference In Projectile-Electron Loss In Energetic Ion-Molecule Collisions, Alexander B. Voitkiv, B. Najjari, Daniel Fischer, Anton N. Artemyev, Andrey S. Surzhykov Jun 2011

Young-Type Interference In Projectile-Electron Loss In Energetic Ion-Molecule Collisions, Alexander B. Voitkiv, B. Najjari, Daniel Fischer, Anton N. Artemyev, Andrey S. Surzhykov

Physics Faculty Research & Creative Works

Under certain conditions an electron bound in a fast projectile ion, colliding with a molecule, interacts mainly with the nuclei and inner shell electrons of atoms forming the molecule. Because of their compact localization in space and distinct separation from each other, these molecular centers play in such collisions a role similar to that of optical slits in light scattering leading to pronounced interference in the spectra of the electron emitted from the projectile.

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Search For Gravitational Wave Bursts From Six Magnetars, J. Abadie, Marco Cavaglia, For Full List Of Authors, See Publisher's Website. Jun 2011

Search For Gravitational Wave Bursts From Six Magnetars, J. Abadie, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

Soft gamma repeaters (SGRs) and anomalous X-ray pulsars (AXPs) are thought to be magnetars: neutron stars powered by extreme magnetic fields. These rare objects are characterized by repeated and sometimes spectacular gamma-ray bursts. The burst mechanism might involve crustal fractures and excitation of non-radial modes which would emit gravitational waves (GWs). We present the results of a search for GW bursts from six galactic magnetars that is sensitive to neutron star f-modes, thought to be the most efficient GW emitting oscillatory modes in compact stars. One of them, SGR 0501+4516, is likely ∼1kpc from Earth, an order of magnitude …

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