Supported Molecular Catalysts: Synthesis, In-Situ Characterization and Performance (open access)

Supported Molecular Catalysts: Synthesis, In-Situ Characterization and Performance

The objectives of our work are: (i) to create solid catalysts with active sites that can function in a cooperative manner to enhance reactivity and selectivity, and (ii) to prepare solid catalysts that can perform multiple reactions in a network that in some cases would not be possible in solution due to the incompatibilities of the various catalytic entities (for example an acid and a base). We carried out extensive reactions to test the nature of the cooperative effect caused by thiol/sulfonic acid interactions. The acid/thiol combination provided an example where the two organic groups should be positioned as close to one another as possible. We also studied a system where this is not possible (acid-base). We investigated simultaneously incorporating acid and base groups into the same material. For the case of acid and bases, there is an optimal separation distance (too close allows for neutralization while too far eliminates any cooperative behavior).
Date: March 13, 2009
Creator: Davis, Mark E.
Object Type: Report
System: The UNT Digital Library
Environmental and Engineering Geophysical University at SAGEEP 2008: Geophysical Instruction for Non-Geophysicists (open access)

Environmental and Engineering Geophysical University at SAGEEP 2008: Geophysical Instruction for Non-Geophysicists

The Environmental and Engineering Geophysical Society (EEGS), a nonprofit professional organization, conducted an educational series of seminars at the Symposium on the Application of Geophysics to Engineering and Environmental Problems (SAGEEP) in Philadelphia in April 2008. The purpose of these seminars, conducted under the name Environmental and Engineering Geophysical University (EEGU) over three days in parallel with the regular SAGEEP technical sessions, was to introduce nontraditional geophysical conference attendees to the appropriate use of geophysics in environmental and engineering projects. Five half-day, classroom-style sessions were led by recognized experts in the application of seismic, electrical, gravity, magnetics, and ground-penetrating radar methods. Classroom sessions were intended to educate regulators, environmental program managers, consultants, and students who are new to near-surface geophysics or are interested in learning how to incorporate appropriate geophysical approaches into characterization or remediation programs or evaluate the suitability of geophysical methods for general classes of environmental or engineering problems.
Date: March 13, 2009
Creator: Paine, Jeffrey G.
Object Type: Report
System: The UNT Digital Library
Environmental Compliance Audit & Assessment Program Manual (open access)

Environmental Compliance Audit & Assessment Program Manual

This document describes the elements, schedule, roles, and responsibilities of the Lawrence Berkeley National Laboratory (LBNL) Environmental Compliance Audit & Assessment Program (ECAAP). The ECAAP has been developed to meet the requirements of DOE Order 450.1A,1 and Executive Order 13423.2 These referenced Orders stipulate that government agencies must develop environmental compliance audit programs to monitor and improve compliance with environmental regulations. As stated specifically in the DOE Order, as a part of a DOE facility's Environmental Management System (EMS), 'An environmental compliance audit and review program that identifies compliance deficiencies and root causes of non-compliance' shall be developed and implemented. The ECAAP has also been developed to satisfy LBNL's institutional technical assurance assessment requirements promulgated in the Environment, Safety and Health (ES&H) Self-Assessment Program (LBNL/PUB-5344) and described by the ES&H Technical Assurance Program (TAP) Manual (LBNL/PUB-913E). The ES&H TAP Manual provides the framework for systematic reviews of ES&H programs with the intent to provide assurance that these programs comply with their guiding regulations, are effective, and are properly implemented. As required by the DOE and Executive Orders and by LBNL's TAP, the goal of the ECAAP is to identify environmental regulatory compliance deficiencies and to determine their respective causes. The …
Date: March 13, 2009
Creator: Thorson, Patrick; Baskin, David; Borglin, Ned; Fox, Robert; Wahl, Linnea; Hatayama, Howard et al.
Object Type: Report
System: The UNT Digital Library
Crossover transition in bag-like models (open access)

Crossover transition in bag-like models

We formulate a simple model for a gas of extended hadrons at zero chemical potential by taking inspiration from the compressible bag model. We show that a crossover transition qualitatively similar to lattice QCD can be reproduced by such a system by including some appropriate additional dynamics. Under certain conditions, at high temperature, the system consist of a finite number of infinitely extended bags,which occupy the entire space. In this situation the system behaves as an ideal gas of quarks and gluons.
Date: March 13, 2009
Creator: Ferroni, Lorenzo & Koch, Volker
Object Type: Article
System: The UNT Digital Library
DIFFERENTIAL SENSITIVITY OF MALE GERM CELLS TO MAINSTREAM AND SIDESTREAM TOBACCO SMOKE IN THE MOUSE (open access)

DIFFERENTIAL SENSITIVITY OF MALE GERM CELLS TO MAINSTREAM AND SIDESTREAM TOBACCO SMOKE IN THE MOUSE

Cigarette smoking in men has been associated with increased chromosomal abnormalities in sperm and with increased risks for spontaneous abortions, birth defects and neonatal death. Little is known, however, about the reproductive consequences of paternal exposure to second-hand smoke. We used a mouse model to investigate the effects of paternal exposure to sidestream (SS) smoke, the main constituent of second-hand smoke, on the genetic integrity and function of sperm, and to determine whether male germ cells were equally sensitive to mainstream (MS) and SS smoke. A series of sperm DNA quality and reproductive endpoints were investigated after exposing male mice for two weeks to MS or SS smoke. Our results indicated that: (i) only SS smoke significantly affected sperm motility; (ii) only MS smoke induced DNA strand breaks in sperm; (iii) both MS and SS smoke increased sperm chromatin structure abnormalities; and (iv) MS smoke affected both fertilization and the rate of early embryonic development, while SS smoke affected fertilization only. These results show that MS and SS smoke have differential effects on the genetic integrity and function of sperm and provide further evidence that male exposure to second-hand smoke, as well as direct cigarette smoke, may diminish a couple's …
Date: March 13, 2009
Creator: Polyzos, Aris; Schmid, Thomas Ernst; Pina-Guzman, Belem; Quintanilla-Vega, Betzabet & Marchetti, Francesco
Object Type: Article
System: The UNT Digital Library
Erratic Dislocations within Funnel Defects in AlN Templates for AlGaNEpitaxial Layer Growth (open access)

Erratic Dislocations within Funnel Defects in AlN Templates for AlGaNEpitaxial Layer Growth

We report our transmission electron microscopy observations of erraticdislocation behavior within funnel-like defects in the top of AlN templates filled withAlGaN from an overlying epitaxial layer. This dislocation behavior is observed inmaterial where phase separation is also observed. Several bare AlN templates wereexamined to determine the formation mechanism of the funnels. Our results suggest that they are formed prior to epitaxial layer deposition due to the presence of impuritiesduring template re-growth. We discuss the erratic dislocation behavior in relation to thepresence of the phase-separated material and the possible effects of these defects on the optoelectronic properties.
Date: March 13, 2009
Creator: Hawkridge, M. E.; Liliental-Weber, Z.; Jin Kim, H.; Choi, S.; Yoo, D.; Ryou, Jae-Hyun et al.
Object Type: Article
System: The UNT Digital Library
Distributed Data-Flow for In-Situ Visualization and Analysis at Petascale (open access)

Distributed Data-Flow for In-Situ Visualization and Analysis at Petascale

We conducted a feasibility study to research modifications to data-flow architectures to enable data-flow to be distributed across multiple machines automatically. Distributed data-flow is a crucial technology to ensure that tools like the VisIt visualization application can provide in-situ data analysis and post-processing for simulations on peta-scale machines. We modified a version of VisIt to study load-balancing trade-offs between light-weight kernel compute environments and dedicated post-processing cluster nodes. Our research focused on memory overheads for contouring operations, which involves variable amounts of generated geometry on each node and computation of normal vectors for all generated vertices. Each compute node independently decided whether to send data to dedicated post-processing nodes at each stage of pipeline execution, depending on available memory. We instrumented the code to allow user settable available memory amounts to test extremely low-overhead compute environments. We performed initial testing of this prototype distributed streaming framework, but did not have time to perform scaling studies at and beyond 1000 compute-nodes.
Date: March 13, 2009
Creator: Laney, D E & Childs, H. R.
Object Type: Report
System: The UNT Digital Library