Digital Commons Network^™

Time-Weighted Average Spme Analysis For In Planta Determination Of Cvocs, Emily M. Sheehan, Matt A. Limmer, Philipp Mayer, Ulrich Gosewinkel Karlson, Joel Gerard Burken

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Potential of Phytoscreening for Plume Delineation at Contaminated Sites Has Promoted Interest in Innovative, Sensitive Contaminant Sampling Techniques. Solid-Phase Microextraction (SPME) Methods Have Been Developed, Offering Quick, Undemanding, Noninvasive Sampling Without the Use of Solvents. in This Study, Time-Weighted Average SPME (TWA-SPME) Sampling Was Evaluated for in Planta Quantification of Chlorinated Solvents. TWA-SPME Was Found to Have Increased Sensitivity over Headspace and Equilibrium SPME Sampling. using a Variety of Chlorinated Solvents and a Polydimethylsiloxane/carboxen (PDMS/CAR) SPME Fiber, Most Compounds Exhibited Near Linear or Linear Uptake over the Sampling Period. Smaller, Less Hydrophobic Compounds Exhibited More Nonlinearity Than Larger, More …

Conflict Detection And Resolution For Product Line Design In A Collaborative Decision Making Environment, Xiaoqing Frank Liu, Eric Christopher Barnes, Juha Erik Savolainen

Computer Science Faculty Research & Creative Works

Ensuring that the non-functional requirements (NFRs), of a system are satisfied is an essential task in software development. However, this task is complicated by the fact that many NFRs conflict with each other from multiple perspectives. It is essential to resolve conflicts collectively in a collaborative decision-making process since stakeholders often disagree on how conflicts should be resolved. in this paper, we describe a method for dividing high-level NFR conflicts within a product line into more manageable sub-problems. Stakeholders make use of an argumentation based collaborative decision support system to determine which design alternatives provide the best trade-offs between NFRs. …

Crystal Structures And Small-Angle X-Ray Scattering Analysis Of Udp-Galactopyranose Mutase From The Pathogenic Fungus Aspergillus Fumigatus, Richa Dhatwalia, Harkewal Singh, Michelle Oppenheimer, Dale B. Karr, Jay C. Nix, Pablo Sobrado, John J. Tanner

Chemistry Faculty Research & Creative Works

UDP-galactopyranose mutase (UGM) is a flavoenzyme that catalyzes the conversion of UDP-galactopyranose to UDP-galactofuranose, which is a central reaction in galactofuranose biosynthesis. Galactofuranose has never been found in humans but is an essential building block of the cell wall and extracellular matrix of many bacteria, fungi, and protozoa. The importance of UGM for the viability of many pathogens and its absence in humans make UGMa potential drug target. Here we report the first crystal structures and small-angle x-ray scattering data for UGM from the fungus Aspergillus fumigatus, the causative agent of aspergillosis. The structures reveal that Aspergillus UGM has several …

Timely Tidbits, Mar. 16, 2012, Library And Learning Resources

Timely Tidbits

No abstract provided.

The Missouri Miner, March 15, 2012

The Missouri Miner Newspaper

No abstract provided.

Timely Tidbits, Mar. 9, 2012, Library And Learning Resources

Timely Tidbits

No abstract provided.

The Missouri Miner, March 8, 2012

The Missouri Miner Newspaper

No abstract provided.

Faculty Senate Minutes March 08, 2012, Missouri University Of Science And Technology Faculty Senate

Minutes & Agendas

No abstract provided.

Doubly And Triply Differential Ionization Measurements Using Femtoamp Beams Of Positrons And Electrons, R. D. Dubois

Physics Faculty Research & Creative Works

Experimental methods and techniques being used to generate doubly and triply differential ionization data for positron and electron beams are discussed. It is shown that even for femtoamp, or smaller, beam intensities, highly detailed differential studies can be performed and differences resulting from kinematic effects due to the sign of the projectile can be identified. Examples using 250 eV impact ionization of molecular nitrogen are provided. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.

Observation Of Spin Glass State In Weakly Ferromagnetic Sr 2fecoo 6 Double Perovskite, R. Pradheesh, Harikrishnan S. Nair, C. M.N. Kumar, Jagat Lamsal, R. Nirmala, P. N. Santhosh, William B. Yelon, S. K. Malik, V. Sankaranarayanan, K. Sethupathi

Physics Faculty Research & Creative Works

A spin glass state is observed in the double perovskite oxide Sr₂FeCoO₆ prepared through sol-gel technique. Initial structural studies using x rays reveal that the compound crystallizes in tetragonal I4/m structure with lattice parameters, a 5.4609(2) Å and c 7.7113(7) Å. the temperature dependent powder x ray diffraction data reveal no structural phase transition in the temperature range 10-300 K. However, the unit cell volume shows an anomaly coinciding with the magnetic transition temperature thereby suggesting a close connection between lattice and magnetism. Neutron diffraction studies and subsequent bond valence sums analysis show that in Sr_{2 …}

A Streamlined Strategy For Biohydrogen Production With Halanaerobium Hydrogeniformans, An Alkaliphilic Bacterium, Matthew B. Begemann, Melanie R. Mormile, Oliver C. Sitton, Judy D. Wall, Dwayne A. Elias

Biological Sciences Faculty Research & Creative Works

Biofuels are anticipated to enable a shift from fossil fuels for renewable transportation and manufacturing fuels, with biohydrogen considered attractive since it could offer the largest reduction of global carbon budgets. Currently, lignocellulosic biohydrogen production remains inefficient with pretreatments that are heavily fossil fuel-dependent. However, bacteria using alkali-treated biomass could streamline biofuel production while reducing costs and fossil fuel needs. An alkaliphilic bacterium, Halanaerobium hydrogeniformans, is described that is capable of biohydrogen production at levels rivaling neutrophilic strains, but at pH 11 and hypersaline conditions. H. hydrogeniformans ferments a variety of 5-and 6-carbon sugars derived from hemicellulose and cellulose …

Spring 2012 E-Certi Newsletter, Center For Educational Research And Teaching Innovation

CAFE Faculty Newsletters

Hello S&T instructors! It’s definitely Spring outside and that means another semester is winding to a close. In this issue, we’re sharing about the new eStudio and what it can do, how to apply for mini-grant funding for educational research, and a tool for helping students read for understanding. Additionally, enjoy an article about Reza Zoughi sharing what he likes to do best.

Missouri S&T Magazine Spring 2012, Missouri S&T Marketing And Communications Department, Miner Alumni Association

Missouri S&T Magazine

No abstract provided.

Spe Members' Views On Sustainability: A Survey, Bonnie Bachman, Shristy Bashyal, Margaret Baumann

Economics Faculty Research & Creative Works

The results of the research conducted to understand sustainability in the plastics industry, initiated with the membership of the Society of Plastics Engineers (SPE). are presented. The implications of sustainability to the plastics industry are discussed. An online survey was created with a set of 27 questions including demographics. The survey was distributed to the Society of Plastics Engineers (SPE) membership via an emails. When asked about the organization-wide definition of sustainability, 45% of the senior managers believed sustainability refers to addressing issues from a long term perspective. When asked who is responsible for addressing sustainability issues, most of the …

The Missouri Miner, March 1, 2012

The Missouri Miner Newspaper

No abstract provided.

Implementation And Testing Of The First Prompt Search For Gravitational Wave Transients With Electromagnetic Counterparts, J. Abadie, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

Aims. A transient astrophysical event observed in both gravitational wave (GW) and electromagnetic (EM) channels would yield rich scientific rewards. A first program initiating EM follow-ups to possible transient GW events has been developed and exercised by the LIGO and Virgo community in association with several partners. In this paper, we describe and evaluate the methods used to promptly identify and localize GW event candidates and to request images of targeted sky locations.

Methods. During two observing periods (Dec. 17, 2009 to Jan. 8, 2010 and Sep. 2 to Oct. 20, 2010), a low-latency analysis pipeline was used to identify …

Bound-Free Pair Production In Ultra-Relativistic Ion Collisions At The Lhc Collider: Analytic Approach To The Total And Differential Cross Sections, Anton N. Artemyev, Ulrich D. Jentschura, Valery G. Serbo, Andrey S. Surzhykov

Physics Faculty Research & Creative Works

A theoretical investigation of the bound-free electron-positron pair production in relativistic heavy ion collisions is presented. Special attention is paid to the positrons emitted under large angles with respect to the beam direction. The measurement of these positrons in coincidence with the down-charged ions is in principle feasible by LHC experiments. In order to provide reliable estimates for such measurements, we employ the equivalent photon approximation together with the Sauter approach and derive simple analytic expressions for the differential pair-production cross section, which compare favorably to the results of available numerical calculations. Based on the analytic expressions, detailed calculations are …

Switching Nonlinearity In A Superconductor-Enhanced Metamaterial, Cihan Kurter, Philippe Tassin, Alexander P. Zhuravel, Lei Zhang, Thomas Koschny, Alexey V. Ustinov, Costas M. Soukoulis, Steven M. Anlage

Physics Faculty Research & Creative Works

We demonstrate a nonlinear metamaterial that can be switched between low and high transmission by controlling the power level of the incident beam. The origin of this nonlinear response is the superconducting Nb thin film employed in the metamaterial structure. We show that with moderate RF power of about 22 dBm it is possible to quench the superconducting state as a result of extremely strong current densities at the corners of the metamaterial's split-ring resonators. We measure a transmission contrast of 10 dB and a change in group delay of 70 ns between the low and high power states.

Low-Energy Electron-Impact Ionization Of Argon: Three-Dimensional Cross Section, Xueguang Ren, Thomas Pfluger, Joachim Hermann Ullrich, Oleg I. Zatsarinny, Klaus Bartschat, Don H. Madison, Alexander Dorn

Physics Faculty Research & Creative Works

Low-energy (E ₀ = 70.8 eV) electron-impact single ionization of a 3p electron in argon has been studied experimentally and theoretically. Our measurements are performed using the so-called reaction microscope technique, which can cover nearly a full 4π solid angle for the emission of a secondary electron with energy below 15 eV and projectile scattering angles ranging from -8° to -30°. The measured cross sections are internormalized across all scattering angles and ejected energies. Several theoretical models were employed to predict the triple-differential cross sections (TDCSs). They include a standard distorted-wave Born approximation (DWBA), a modified version to account for …

Low Energy (E,2e) Measurements Of Ch⁴ And Neon In The Perpendicular Plane, Kate L. Nixon, Andrew James Murray, Hari Chaluvadi, Sadek Amami, Don H. Madison, Chuangang Ning

Physics Faculty Research & Creative Works

Low energy experimental and theoretical triple differential cross sections for the highest occupied molecular orbital of methane (1t₂) and for the 2p atomic orbital of neon are presented and compared. These targets are iso-electronic, each containing 10 electrons and the chosen orbital within each target has p-electron character. Observation of the differences and similarities of the cross sections for these two species hence gives insight into the different scattering mechanisms occurring for atomic and molecular targets. The experiments used perpendicular, symmetric kinematics with outgoing electron energies between 1.5 eV and 30 eV for CH₄ and 2.5 eV …

The Flow And Fracture Of Advanced Glasses - An Overview, Tanguy Rouxel, Richard K. Brow

Materials Science and Engineering Faculty Research & Creative Works

Editors' note on appropriate occasions, the International Journal of Applied Glass Science will engage the services of Guest Editors to help focus on topics of special interest to the international glass community. in this inaugural issue of this initiative, Professors Tanguy Rouxel and Richard Brow have accomplished just that in their overview of the subject "Flow and Fracture of Advanced Glasses." an introduction to this material and brief biographical sketch are given below. Our sincere thanks are extended to them for their help and cooperation throughout this undertaking, and especially the authors who contributed so much of their time, energy, …

Advantages Of Gan Based Light-Emitting Diodes With A P-Ingan Hole Reservoir Layer, Taiping Lu, Shuti Li, Chao Liu, Kang Zhang, Yiqin Xu, Jinhui Tong, Lejuan Wu, Hailong Wang, Xiaodong Yang, Yian Yin, Guowei Xiao, Yugang Zhou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A p-type InGaN hole reservoir layer (HRL) was designed and incorporated in GaN based light-emitting diodes (LEDs) to enhance hole injection efficiency and alleviate efficiency droop. The fabricated LEDs with p-type HRL exhibited higher light output power, smaller emission energy shift and broadening as compared to its counterpart. Based on electrical and optical characteristics analysis and numerical simulation, these improvements are mainly attributed to the alleviated band bending in the last couple of quantum well and electron blocking layer, and thus better hole injection efficiency. Meanwhile, the efficiency droop can be effectively mitigated when the p-InGaN HRL was used.

Theory For Dynamic Longitudinal Dispersion In Fractures And Rivers With Poiseuille Flow, Lichun Wang, M. Bayani Cardenas, Wen Deng, Philip C. Bennett

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

We present a theory for dynamic longitudinal dispersion coefficient (D) for transport by Poiseuille flow, the foundation for models of many natural systems, such as in fractures or rivers. Our theory describes the mixing and spreading process from molecular diffusion, through anomalous transport, and until Taylor dispersion. D is a sixth order function of fracture aperture (b) or river width (W). The time (T) and length (L) scales that separate preasymptotic and asymptotic dispersive transport behavior are T = b²/(4D _m), where D_m is the molecular diffusion …

System For Detection Of Malicious Wireless Device Patterns, Shikhar P. Acharya, R. Arora, Ivan G. Guardiola

Engineering Management and Systems Engineering Faculty Research & Creative Works

The research within presents the use of Hidden Markov Models (HMM) for the detection of wireless devices in highly noisy environments using their unintended electromagnetic emissions (UEE). All electromagnetic devices emit such radiation that is unique to the electronics, housing, and other device attributes. This pattern recognition system can provide continuous detection analysis and can provide ideal information regarding the distance to an unknown device. An experiment was performed where UEE of a device was detected by a spectrum analyzer. Experimental result shows that our model can accurately detect if there is a device nearby emitting UEE or not.

Resource Scheduling Under Uncertainty In A Smart Grid With Renewables And Plug-In Vehicles, Ahmed Yousuf Saber, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

The power system and transportation sector are our planet's main sources of greenhouse gas emissions. Renewable energy sources (RESs), mainly wind and solar, can reduce emissions from the electric energy sector; however, they are very intermittent. Likewise, next generation plug-in vehicles, which include plug-in hybrid electric vehicles and electric vehicles with vehicletogrid capability, referred to as grid able vehicles (GVs) by the authors, can reduce emissions from the transportation sector. GVs can be used as loads, energy sources (small portable power plants) and energy storage units in a smart grid integrated with renewable energy sources. However, uncertainty surrounds the controllability …

Linear Precoding For Relay Networks: A Perspective On Finite-Alphabet Inputs, Weiliang Zeng, Yahong Rosa Zheng, Mingxi Wang, Jianhua Lu

Electrical and Computer Engineering Faculty Research & Creative Works

This paper considers the precoder design for dual-hop amplify-and-forward relay networks and formulates the design from the standpoint of finite-alphabet inputs. in particular, the mutual information is employed as the utility function, which, however, results in a nonlinear and nonconcave problem. This paper exploits the structure of the optimal precoder that maximizes the mutual information and develops a two-step algorithm based on convex optimization and optimization on the Stiefel manifold. by doing so, the proposed algorithm is insensitive to initial point selection and able to achieve a near global optimal precoder solution. Besides, it converges fast and offers high mutual …

Interpolation-Based Parameterized Model Order Reduction Of Delayed Systems, Francesco Ferranti, Michel Nakhla, Giulio Antonini, Tom Dhaene, Luc Knockaert, Albert E. Ruehli

Electrical and Computer Engineering Faculty Research & Creative Works

Three-dimensional electromagnetic methods are fundamental tools for the analysis and design of high-speed systems. These methods often generate large systems of equations, and model order reduction (MOR) methods are used to reduce such a high complexity. When the geometric dimensions become electrically large or signal waveform rise times decrease, time delays must be included in the modeling. Design space optimization and exploration are usually performed during a typical design process that consequently requires repeated simulations for different design parameter values. Efficient performing of these design activities calls for parameterized model order reduction (PMOR) methods, which are able to reduce large …

Finite-Element-Based Generalized Impedance Boundary Condition For Modeling Plasmonic Nanostructures, Shiquan He, Wei E.I. Sha, Lijun Jiang, Wallace C.H. Choy, Weng Cho Chew, Zaiping Nie

Electrical and Computer Engineering Faculty Research & Creative Works

The superior ability of plasmonic structures to manipulate light has propelled their extensive applications in nanophotonics techniques and devices. Computational electromagnetics plays a critical role in characterizing and optimizing the nanometallic structures. In this paper, a general numerical algorithm, which is different from the commonly used discrete dipole approximation, the finite-difference time-domain, and the surface integral equation (SIE) method, is proposed to model plasmonic nanostructures. In this algorithm, the generalized impedance boundary condition (GIBC) based on the finite element method (FEM) is formulated and converted to the SIE. The plasmonic nanostructures with arbitrary inhomogeneity and shapes are modeled by the …

Timely Tidbits, Feb. 24, 2012, Library And Learning Resources

Timely Tidbits

No abstract provided.

The Missouri Miner, February 23, 2012

The Missouri Miner Newspaper

No abstract provided.