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2011 Organometallic Chemistry (July 10-15, 2011, Salve Regina University, Newport, RI) (open access)

2011 Organometallic Chemistry (July 10-15, 2011, Salve Regina University, Newport, RI)

Organometallic chemistry has played and will continue to play a significant role in helping us understand the way bonds are made or broken in the presence of a transition metal complex. Current challenges range from the efficient exploitation of energy resources to the creative use of natural and artificial enzymes. Most of the new advances in the area are due to our extended understanding of processes at a molecular level due to new mechanistic studies, techniques to detect reaction intermediates and theory. The conference will bring the most recent advances in the field including nanocatalysis, surface organometallic chemistry, characterization techniques, new chemical reactivity and theoretical approaches along with applications to organic synthesis and the discovery of new materials. The Conference will bring together a collection of investigators who are at the forefront of their field, and will provide opportunities for junior scientists and graduate students to present their work in poster format and exchange ideas with leaders in the field. Six outstanding posters will be selected for short talks. The collegial atmosphere of this Conference, with programmed discussion sessions as well as opportunities for informal gatherings in the afternoons and evenings, provides an avenue for scientists from different disciplines to …
Date: July 15, 2011
Creator: Bunel, Dr. Emilio
System: The UNT Digital Library
Automatic Black-Box Model Order Reduction using Radial Basis Functions (open access)

Automatic Black-Box Model Order Reduction using Radial Basis Functions

Finite elements methods have long made use of model order reduction (MOR), particularly in the context of fast freqeucny sweeps. In this paper, we discuss a black-box MOR technique, applicable to a many solution methods and not restricted only to spectral responses. We also discuss automated methods for generating a reduced order model that meets a given error tolerance. Numerical examples demonstrate the effectiveness and wide applicability of the method. With the advent of improved computing hardware and numerous fast solution techniques, the field of computational electromagnetics are progressed rapidly in terms of the size and complexity of problems that can be solved. Numerous applications, however, require the solution of a problem for many different configurations, including optimization, parameter exploration, and uncertainly quantification, where the parameters that may be changed include frequency, material properties, geometric dimensions, etc. In such cases, thousands of solutions may be needed, so solve times of even a few minutes can be burdensome. Model order reduction (MOR) may alleviate this difficulty by creating a small model that can be evaluated quickly. Many MOR techniques have been applied to electromagnetic problems over the past few decades, particularly in the context of fast frequency sweeps. Recent works have …
Date: July 15, 2011
Creator: Stephanson, M. B.; Lee, J. F. & White, D. A.
System: The UNT Digital Library
Impact of CO2 geological sequestration on the nucleation of earthquakes (open access)

Impact of CO2 geological sequestration on the nucleation of earthquakes

None
Date: July 15, 2011
Creator: Cappa, F. & Rutqvist, J.
System: The UNT Digital Library
Geophysical monitoring and reactive transport modeling of ureolytically-driven calcium carbonate precipitation (open access)

Geophysical monitoring and reactive transport modeling of ureolytically-driven calcium carbonate precipitation

Ureolytically-driven calcium carbonate precipitation is the basis for a promising in-situ remediation method for sequestration of divalent radionuclide and trace metal ions. It has also been proposed for use in geotechnical engineering for soil strengthening applications. Monitoring the occurrence, spatial distribution, and temporal evolution of calcium carbonate precipitation in the subsurface is critical for evaluating the performance of this technology and for developing the predictive models needed for engineering application. In this study, we conducted laboratory column experiments using natural sediment and groundwater to evaluate the utility of geophysical (complex resistivity and seismic) sensing methods, dynamic synchrotron x-ray computed tomography (micro-CT), and reactive transport modeling for tracking ureolytically-driven calcium carbonate precipitation processes under site relevant conditions. Reactive transport modeling with TOUGHREACT successfully simulated the changes of the major chemical components during urea hydrolysis. Even at the relatively low level of urea hydrolysis observed in the experiments, the simulations predicted an enhanced calcium carbonate precipitation rate that was 3-4 times greater than the baseline level. Reactive transport modeling results, geophysical monitoring data and micro-CT imaging correlated well with reaction processes validated by geochemical data. In particular, increases in ionic strength of the pore fluid during urea hydrolysis predicted by geochemical modeling …
Date: July 15, 2011
Creator: Wu, Y.; Ajo-Franklin, J. B.; Spycher, N.; Hubbard, S. S.; Zhang, G.; Williams, K. H. et al.
System: The UNT Digital Library
2011 Photochemistry Gordon Research Conference (July10-15, 2011, Stonehill College, Easton, MA) (open access)

2011 Photochemistry Gordon Research Conference (July10-15, 2011, Stonehill College, Easton, MA)

Photochemistry has wide implications on fundamental science with technological applications that range from synthetic and mechanistic organic and inorganic chemistry to sensing/manipulation in the biological sciences to viable solar energy conversion assemblies. The 2011 Gordon Research Conference on Photochemistry will highlight recent advances on photochemical reactions, their mechanisms, spectroscopic techniques and applications to materials, organic synthesis, and biology. The conference will continue its long tradition on dynamic discussions on recent advances and unsolved scientific problems. The format of lectures, poster presentations and informal discussions provides an ideal venue for students and post-doctoral fellows to interact with the leaders in the field. These junior scientists will have an opportunity to participate in the Gordon Research Seminar on Photochemistry to be held prior to the GRC. The GRS will focus on photochemical aspects of solar energy conversion. Four abstracts for posters at the GRC and presentations at the GRS will be selected as short talks at the GRC.
Date: July 15, 2011
Creator: Meyer, Prof. Gerald
System: The UNT Digital Library
A Framework for the Evaluation of the Cost and Benefits of Microgrids (open access)

A Framework for the Evaluation of the Cost and Benefits of Microgrids

A Microgrid is recognized as an innovative technology to help integrate renewables into distribution systems and to provide additional benefits to a variety of stakeholders, such as offsetting infrastructure investments and improving the reliability of the local system. However, these systems require additional investments for control infrastructure, and as such, additional costs and the anticipated benefits need to be quantified in order to determine whether the investment is economically feasible. This paper proposes a methodology for systematizing and representing benefits and their interrelationships based on the UML Use Case paradigm, which allows complex systems to be represented in a concise, elegant format. This methodology is demonstrated by determining the economic feasibility of a Microgrid and Distributed Generation installed on a typical Canadian rural distribution system model as a case study. The study attempts to minimize the cost of energy served to the community, considering the fixed costs associated with Microgrids and Distributed Generation, and suggests benefits to a variety of stakeholders.
Date: July 15, 2011
Creator: Morris, Greg Young; Abbey, Chad; Joos, Geza & Marnay, Chris
System: The UNT Digital Library
Generalized schemes for high throughput manipulation of the Desulfovibrio vulgaris Hildenborough genome (open access)

Generalized schemes for high throughput manipulation of the Desulfovibrio vulgaris Hildenborough genome

The ability to conduct advanced functional genomic studies of the thousands of sequenced bacteria has been hampered by the lack of available tools for making high- throughput chromosomal manipulations in a systematic manner that can be applied across diverse species. In this work, we highlight the use of synthetic biological tools to assemble custom suicide vectors with reusable and interchangeable DNA “parts” to facilitate chromosomal modification at designated loci. These constructs enable an array of downstream applications including gene replacement and creation of gene fusions with affinity purification or localization tags. We employed this approach to engineer chromosomal modifications in a bacterium that has previously proven difficult to manipulate genetically, Desulfovibrio vulgaris Hildenborough, to generate a library of over 700 strains. Furthermore, we demonstrate how these modifications can be used for examining metabolic pathways, protein-protein interactions, and protein localization. The ubiquity of suicide constructs in gene replacement throughout biology suggests that this approach can be applied to engineer a broad range of species for a diverse array of systems biological applications and is amenable to high-throughput implementation.
Date: July 15, 2011
Creator: Chhabra, S. R.; Butland, G.; Elias, D.; Chandonia, J. M.; Fok, V.; Juba, T. et al.
System: The UNT Digital Library
Tunable Laser Plasma Accelerator based on Longitudinal Density Tailoring (open access)

Tunable Laser Plasma Accelerator based on Longitudinal Density Tailoring

Laser plasma accelerators have produced high-quality electron beams with GeV energies from cm-scale devices and are being investigated as hyperspectral fs light sources producing THz to {gamma}-ray radiation and as drivers for future high-energy colliders. These applications require a high degree of stability, beam quality and tunability. Here we report on a technique to inject electrons into the accelerating field of a laser-driven plasma wave and coupling of this injector to a lower-density, separately tunable plasma for further acceleration. The technique relies on a single laser pulse powering a plasma structure with a tailored longitudinal density profile, to produce beams that can be tuned in the range of 100-400 MeV with percent-level stability, using laser pulses of less than 40 TW. The resulting device is a simple stand-alone accelerator or the front end for a multistage higher-energy accelerator.
Date: July 15, 2011
Creator: Gonsalves, Anthony; Nakamura, Kei; Lin, Chen; Panasenko, Dmitriy; Shiraishi, Satomi; Sokollik, Thomas et al.
System: The UNT Digital Library
Genetic manipulation of the obligate chemolithoautotrophic bacterium Thiobacillus denitrificans (open access)

Genetic manipulation of the obligate chemolithoautotrophic bacterium Thiobacillus denitrificans

Chemolithoautotrophic bacteria can be of industrial and environmental importance, but they present a challenge for systems biology studies, as their central metabolism deviates from that of model organisms and there is a much less extensive experimental basis for their gene annotation than for typical organoheterotrophs. For microbes with sequenced genomes but unconventional metabolism, the ability to create knockout mutations can be a powerful tool for functional genomics and thereby render an organism more amenable to systems biology approaches. In this chapter, we describe a genetic system for Thiobacillus denitrificans, with which insertion mutations can be introduced by homologous recombination and complemented in trans. Insertion mutations are generated by in vitro transposition, the mutated genes are amplified by the PCR, and the amplicons are introduced into T. denitrificans by electroporation. Use of a complementation vector, pTL2, based on the IncP plasmid pRR10 is also addressed.
Date: July 15, 2011
Creator: Beller, H.R.; Legler, T.C. & Kane, S.R.
System: The UNT Digital Library
ATOMIC FORCE LITHOGRAPHY OF NANO/MICROFLUIDIC CHANNELS FOR VERIFICATION AND MONITORING OF AQUEOUS SOLUTIONS (open access)

ATOMIC FORCE LITHOGRAPHY OF NANO/MICROFLUIDIC CHANNELS FOR VERIFICATION AND MONITORING OF AQUEOUS SOLUTIONS

The growing interest in the physics of fluidic flow in nanoscale channels, as well as the possibility for high sensitive detection of ions and single molecules is driving the development of nanofluidic channels. The enrichment of charged analytes due to electric field-controlled flow and surface charge/dipole interactions along the channel can lead to enhancement of sensitivity and limits-of-detection in sensor instruments. Nuclear material processing, waste remediation, and nuclear non-proliferation applications can greatly benefit from this capability. Atomic force microscopy (AFM) provides a low-cost alternative for the machining of disposable nanochannels. The small AFM tip diameter (< 10 nm) can provide for features at scales restricted in conventional optical and electron-beam lithography. This work presents preliminary results on the fabrication of nano/microfluidic channels on polymer films deposited on quartz substrates by AFM lithography.
Date: July 15, 2011
Creator: Mendez-Torres, A.; Torres, R. & Lam, P.
System: The UNT Digital Library
Exploring the concept of compressed air energy storage (CAES) in lined rock caverns at shallow depth: A modeling study of air tightness and energy balance (open access)

Exploring the concept of compressed air energy storage (CAES) in lined rock caverns at shallow depth: A modeling study of air tightness and energy balance

This paper presents a numerical modeling study of coupled thermodynamic, multiphase fluid flow and heat transport associated with underground compressed air energy storage (CAES) in lined rock caverns. Specifically, we explored the concept of using concrete lined caverns at a relatively shallow depth for which constructing and operational costs may be reduced if air tightness and stability can be assured. Our analysis showed that the key parameter to assure long-term air tightness in such a system was the permeability of both the concrete lining and the surrounding rock. The analysis also indicated that a concrete lining with a permeability of less than 1×10{sup -18} m{sup 2} would result in an acceptable air leakage rate of less than 1%, with the operational pressure range between 5 and 8 MPa at a depth of 100 m. It was further noted that capillary retention properties and the initial liquid saturation of the lining were very important. Indeed, air leakage could be effectively prevented when the air-entry pressure of the concrete lining is higher than the operational air pressure and when the lining is kept moist at a relatively high liquid saturation. Our subsequent energy-balance analysis demonstrated that the energy loss for a daily …
Date: July 15, 2011
Creator: Kim, Hyung-Mok; Rutqvist, Jonny; Ryu, Dong-Woo; Sunwoo, Choon & Song, Won-Kyong
System: The UNT Digital Library