Student Abstracts: ORNL

A Computational Model for Analyzing the Biochemical Pathways of Matrix Metalloproteinase (MMP) 2&9 in Collagen Type IV Proteolysis. ELIZABETH O'QUINN O'QUINN (Wofford College, Spartanburg, SC, 29369) KARA KRUSE (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

Cardiovascular disease is the leading cause of death in first world countries. The imbalance of matrix degrading enzymes and structural proteins within the extracellular matrix of an arterial wall is a critical factor in cardiovascular disease processes. Matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) degradation of collagen type IV results in migration and proliferation of vascular smooth muscle cells; this can lead to further narrowing of a diseased artery. Kinetic modeling of proteolysis is an approach which can be used to understand complex systems by describing the enzyme’s mechanism and behavior quantitatively. In this research project, a computational model of biochemical pathways involved in activation and inhibition of MMP-2 and MMP-9 proteolysis of collagen type IV is being developed. Separate MMP-2 and MMP-9 models have been implemented within JSim, a software application developed by the University of Washington. Since MMP-2 and MMP-9 pathways overlap, the individual models will be integrated in the future. This MMP-2 model was also implemented in JDesigner, a tool of the Systems Biology Workbench, and DEVS, a discrete event system specification, for comparison of model environments. Various experimental methods for obtaining quantitative reaction rate parameters were explored, including high pressure liquid chromatography (HPLC) and florescence polarization. By pairing HPLC separation, largely by hydrophobic property, with spectrometry techniques, protein and peptide identification and quantification is possible. Previous literature suggests the use of HPLC to measure enzymatic activity, by using traces of the product/substrate itself as an internal standard. An experimental protocol for the measurement of the enzymatic activity of MMP-2 and MMP-9 is being developed. HPLC baseline standards for the individual substrates and enzymes are currently being measured and optimized. After baseline standards are determined the MMP enzymatic activity can be determined. The HPLC experimental results will be analyzed to derive the reaction rate parameters needed by the computational model. The use of HPLC methods to analyze the enzymatic activity of MMP-2 with collagen type IV and other correlated substrates provides parameters which cannot be obtained through literature. This research is in collaboration with the Vascular Research Laboratory at the University of Tennessee Medical Center in Knoxville.

A Rational Approach for Crystallization of Proteins in Deuterated Media. ALEXIS RAE DEL CASTILLO (California State University, Chanel Islands, Camarillo, CA, 93012) HUGH O'NEILL (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

Neutron crystallography is emerging as a powerful tool for the study of protein structure and dynamics. In neutron crystallography the neutrons interact weakly with the nucleus of an atom and therefore are a highly penetrating and non-destructive probe. Unlike x-rays, which interact with the electron cloud surrounding an atom, neutrons can detect lighter atoms such as hydrogen in the presence of heavier ones and differentiate between them. The aim of this study was to determine how deuterium oxide influences the crystallization behavior of proteins compared to crystallization in hydrogenated media. This will allow a rational design approach for growing protein crystals for neutron crystallography. In order to achieve this goal a range of proteins were selected for crystallization studies. Some proteins, such as aprotinin, cytochrome c, B-lactoglobulin and papain were obtained commercially. In addition, two variants of GFP, from Aequorea victoria and A. coerulescens, were over-expressed in Escherichia coli in hydrogenated and deuterated media. The recombinant proteins were then purified to homogeneity by three-phase partitioning and anion exchange chromatography. The conditions for crystallization of each protein were determined using a high throughput platform that can screen 1536 different crystallization solutions simultaneously. Each protein produced crystals in several different solutions. The conditions that produced crystals were then subjected to a second screening procedure called Drop Volume Ratio Temperature (DVR/T) to further optimize and refine the chemical and physical parameters that produced crystals in the initial screen. A DVR/T phase diagram has been completed for aprotinin, cytochrome c, B-lactoglobulin A and papain in hydrogenated buffer. Currently, a DVR/T screen in deuterated buffer is underway for these proteins.

Neutron crystallography is emerging as a powerful tool for the study of protein structure and dynamics. In neutron crystallography the neutrons interact weakly with the nucleus of an atom and therefore are a highly penetrating and non-destructive probe. Unlike x-rays, which interact with the electron cloud surrounding an atom, neutrons can detect lighter atoms such as hydrogen in the presence of heavier ones and differentiate between them. The aim of this study was to determine how deuterium oxide influences the crystallization behavior of proteins compared to crystallization in hydrogenated media. This will allow a rational design approach for growing protein crystals for neutron crystallography. In order to achieve this goal a range of proteins were selected for crystallization studies. Some proteins, such as aprotinin, cytochrome c, myoglobin, phospholipase and others were obtained commercially in their purified form. Green fluorescent protein (GFP) and rubredoxin, were over-expressed in Escherichia coli and purified from cell-free extracts. The optimal conditions for crystallization were determined using a high throughput platform that can screen 1536 different crystallization conditions simultaneously. Expression of recombinant proteins was induced with isopropyl ß-D-1-thiogalactopyranoside (IPTG). The cells were lysed by sonication followed by centrifugation. The proteins were purified by ion exchange chromatography and size exclusion chromatography. The purification process was monitored by UV/visible absorption spectrophotometry, circular dichroism spectroscopy, fluorescence excitation/emission and sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis (PAGE). Currently the 1536 screen in H₂O media has been completed for several of the proteins mentioned above and the experiments to determine how D₂O influences crystallization conditions are underway. In addition, techniques to produce per-deuterated forms of GFP and rubredoxin are being developed by adapting E. coli to grow in D₂O based media.

A Review of Empirical Methods for the Derivation of Parameters in a Theoretical Model of Matrix Metalloproteinase 2 & 9 Proteolysis of Collagen Type IV. ELIZABETH O'QUINN O'QUINN (Wofford College, Spartanburg, SC, 29303) KARA KRUSE (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

Cardiovascular disease is the leading cause of death in first world countries. An imbalance of matrix degrading enzymes and structural proteins within the extracellular matrix of an arterial wall is a critical factor in cardiovascular disease processes. An increase in matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9), as part of the inflammatory process, results in degradation of collagen type IV influencing the migration and proliferation of vascular smooth muscle cells; this can lead to further narrowing of a diseased artery. Kinetic modeling of proteolysis is an approach which can be used to understand complex systems by describing enzymatic mechanisms, cellular processes, and the system’s behavior quantitatively. In this research project, a computational model of the biochemical pathways involved in activation and inhibition of MMP-2 and MMP-9 proteolysis of collagen type IV is being developed from empirical data and published data. Separate and integrated models of MMP-2 and MMP-9 pathways have been implemented within JSim, a software application developed by the University of Washington. In addition to the enzyme model a cellular migration model is also being developed for the simulation of VSMC migration and will be explored further. The utilization of reverse-phase high pressure liquid chromatography (HPLC) methods for obtaining quantitative reaction rate parameters are being explored for the estimation of parameters not previously published in the literature. By pairing HPLC separation with spectrometry techniques, protein and peptide identification and quantification are possible. Experimental protocols for the measurement of the enzymatic activity of MMP-2 and MMP-9 proteolysis of collagen type IV are being developed to obtain empirical data. These experimental results are then analyzed to derive the rate parameters needed in the computational model. The use of HPLC methods to analyze the enzymatic activity and cellular activity provides parameters which cannot be obtained through literature. This research is in collaboration with the Vascular Research Laboratory at the University of Tennessee Medical Center in Knoxville.

AC Losses in YBCO Superconducting Cables. DANIEL SIMS (Tennessee Technological University, Cookeville, TN, 38505) ROBERT DUCKWORTH (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

To better supply power to dense urban areas, superconducting power cables are one solution that can accomplish this within existing electrical ductwork. While "first generation" Bi-Sr-Ca-Cu-O (BSCCO) tapes are currently being used in several demonstration cable projects around the world, its cost may limit the market penetration of commercial superconducting cables. As a potential low cost alternative, "second generation" Y-Ba-Cu-O (YBCO) tapes have started to meet and exceed the current-carrying performance of BSCCO tapes with lengths greater than 100 m and could be used in superconducting cables in the near future. AC loss, which is the amount of heat generation of a superconducting cable under ac current, is a critical design parameter since it directly impacts the size of the cryogenic refrigeration system and thus impacts the overall cost. The goal of this project is to make a technical evaluation of current YBCO tape architectures, which are currently being supplied in the United States by American Superconductor (AMSC) and SuperPower (SP). Prototype cables with lengths of 1.25 m and former diameters of 3.81 cm were made from the 4-mm wide YBCO tapes to evaluate the effect of the tape architecture on ac loss. A well-established electrical measurement method and a thermal measurement method were employed to accurately characterize each cable. A finite element model was used to make sure that the heater used in the thermal method was sized appropriately to match the heat generated by the cable. As a measure of the cable performance, the critical current was measured under dc conditions and was found to be 5380 A for the AMSC cable and 4400 A for the SP cable, which agreed well with the single tape critical current for each type of YBCO. With respect to the measured electrical ac loss at 3 kA_rms, the AMSC cable was 3 W/m, while the SP cable was 6 W/m. While this might indicate some advantage to AMSC YBCO tapes, comparing the ac loss in each cable as a function of the ratio of the peak current to the cable critical current showed the functional dependence of each cable to be similar as the current approached 3 kA_rms. Comparing the ac loss measurement methods, differences between the thermal and electrical ac loss measurements suggest refinement of the thermometry is needed and is currently under further investigation.

Agt1 Promoter Sequence Analysis in the Collaborative Cross Parental Mouse Strains. JEANNA KIDWELL (Christopher Newport University, Newport News, VA, 23606) BRYNN VOY (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

The Collaborative Cross (CC) is a unique mouse genetic reference population being generated at the Oak Ridge National Laboratory. This cross will consist of approximately one thousand recombinant inbred (RI) strains of mice derived from eight parental strains that were chosen for their genetic and phenotypic diversity. Each strain will contain a unique combination of alleles from the eight parental genomes, creating a population with genetic and phenotypic diversity on par with the human population and a novel resource for the study of heritable disease in humans. We are using the CC population to study the association between adipose tissue production of Angiotensinogen (Agt) on obesity and type 2 diabetes. Agt is the substrate for Angiotensin II, a bioactive hormone that regulates insulin sensitivity as well as many other physiological processes. We sequenced the Agt1 promoter region (about 1.2 kilobases upstream from Agt1) in the 8 CC parental strains in an attempt to identify regulatory polymorphisms that cause wide variation, up to 100-fold, of adipose Agt mRNA expression levels across the CC parental strains. DNA was extracted from mouse ear clips using a modified "Hot Shot" protocol (alkaline lysis followed by neutralization). The Agt promoter was amplified using Polymerase Chain Reaction with a series of six oligonucleotide primers. DNA sequencing was performed at the UTK Molecular Biology Resource Facility. Sequence analysis indicates several single nucleotide polymorphisms between the strains as well as a three base pair deletion present in three strains (A/J, NZO, and CAST) and not present in the other five strains (C57BL/6J, 129, NOD, PWK, WSB). Future experiments will be directed towards determining the impact of these polymorphisms on Agt transcription.

Air Transport of Commercial Spent Nuclear Fuel (SNF) Assemblies. GIANCARLO PENA (Florida International University, Miami, FL, 33174) JONATHAN M. HAIRE (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

The world is experiencing transformations as energy prices increase, and nuclear technology is not an exception. However, the method of transporting spent nuclear fuel (SNF) has not changed in decades. Currently, in the U.S., SNF casks are shipped by train, truck, and ship. This work examined the technical feasibility of transporting SNF casks by aircraft. Air transport of research reactor SNF has already occurred between countries because of geographical and political reasons. It is concluded that air transport of commercial spent nuclear power reactor fuel is feasible in the U.S. with as many as 21 fuel assemblies shipped at one time. The major constraint that limits the number of SNF assemblies is the lift weight of the aircraft. This study uses the maximum aircraft payload as 154 tons - the net payload of the Boeing 747-8 air freighter. Existing casks from different private companies were analyzed. Sensitivity analyses were performed for transporting different numbers of SNF assemblies. The smaller the number of SNF casks transported, the lower the cask weight. Shielding analyses were conducted using ORNL computer codes CAPSIZE, SCOPE, and SCALE, the objective when using these codes was to optimize the amount of radiation shielding, while meeting regulatory radiation dose requirements. Impact crash analyses were conducted with CTH code to demonstrate crash compliance regulations. Recently, the U.S department of Energy (DOE) submitted a license application for a permanent geological repository in Yucca Mountain, Nevada. The cost of air shipments of SNF assemblies to surface storage for SNF at Yucca Mountain is less than the costs of building the proposed railway spur to the Yucca Mountain geologic repository. Nuclear power is essential if the world intends to reduce the levels of greenhouse gases that warm the earth and by adopting this method of transporting SNF, time and costs will be reduced.

Analysis of Interstate Weigh Station Viewer Performance. RAMON COLON MENDOZA (Florida International University, Miami, FL, 33015) DAVID E. HILL (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

After the 9-11 attacks, the United States has increased its focus on developing technologies designed to warn us in the event of another attack, and to prevent these attacks from happening. The Sensor Net research group at ORNL is participating in this effort by developing systems to give critical real-time information to federal, state, and local emergency response decision makers. Sensor Net’s Southeastern Transportation Corridor Pilot (SETCP) Project utilizes interstate weigh stations not only to weigh the passing trucks but also to check for Gamma and Neutron radiation inside the truck without the aid of a human in close proximity. My role is to characterize and analyze the data from the South Carolina weigh station on I-26W and the Tennessee weigh station on I-40 E. The purpose is to find patterns in the truck traffic as well as to find patterns of inconsistency that the system makes repeatedly. Also I analyze the improvement after the repairs. Inconsistence patterns are found by analyzing the data, looking for missing information, and how often it happens. Traffic Patterns are found by grouping all the data and making graphs and charts that show the flow of the traffic, the kind of truck traffic, the number of alarms, as well as other information. It has been found that Monday, Tuesday, Wednesday, and Thursday the truck traffic is heaviest. Both the component to determine truck length and the component to read each truck’s license plate were inaccurate, but have now been fixed as a result of my data analysis.

Analysis of Meteorological Observations Over the Former USSR, 1950-2000. GARRETT MARINO (Massachusetts Institute of Technology, Cambridge, MA, 2139) DALE P. KAISER (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

Climate change studies require the processing and analysis of large compilations of meteorological data. Past studies investigated trends in meteorological variables over the former Soviet Union using data from a 223-station network spanning 1936-1990. A newly-acquired update to the database includes data through 2000. The database has been made available through cooperation between the two principal climate data centers of the United States and the former Soviet Union: the National Climatic Data Center, in Asheville, North Carolina and the All-Russian Research Institute of Hydrometeorological Information - World Data Centre in Obninsk, Russia. Station records consist of 6- and 3-hourly observations of 25 meteorological variables including temperature, precipitation, cloud amount and type, pressure, humidity, and wind speed and direction. The 6-hourly observations extend from 1936 through 1965; 3-hourly observations extend from 1966 through 2000. To ensure high data quality, extensive quality assurance (QA) checks examined the data for completeness, reasonableness, and accuracy. We found significant gaps in some records from observational gaps or measurement values deemed erroneous. Also, World War II and the breakup of the Soviet Union affected some records’ completeness. Therefore, this analysis examined the period 1950-2000 for 125 stations. Total and low cloud amount, frequencies of various cloud types, and air temperature were all extracted from the dataset and plotted by station to assess variability and any long-term trends. The results showed that trends found by previous researchers using data through 1990 have continued through 2000. Total cloud cover significantly increased (95% confidence level) at 0.2%/decade despite a significant decrease in low cloud cover of 1.1%/dec. Meanwhile, low level stratiform clouds significantly decreased by 1.6%/dec and cumulus clouds significantly increased at 1.4%/dec. Stratiform clouds are associated with atmospheric stability and frontal passages. A warmer planet and the resultant reduction of both the meridional temperature gradient and atmospheric stability may be causing these cloud trends. Air temperature did exhibit a significant increase of 0.2°C/dec. The Russian database represents a wealth of meteorological information for a large and climatologically important portion of the earth’s land area, and should prove useful for a wide variety of additional regional climate change studies.

Analysis of the Biological Effects of Aspirated Carbon Nanohorn Particles in Mice using Scanning Near-Field Ultrasound Holography. KATHERINE VENMAR (Denison University, Granville, OH, 43023) THOMAS THUNDAT (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

Engineered nanomaterials, because of their enhanced physicochemical properties compared to their bulk form, are finding an increasingly important role in many potential commercial applications. However, the health effects of nanomaterials are not well understood or thoroughly investigated. Therefore, more studies are needed to examine different types of nanomaterials and the biological responses they invoke. The purpose of this research was to examine the effects of aspirating single-walled carbon nanohorns (SWCNHs) in vivo using mice. Bronchoalveolar lavage (BAL) and blood samples were collected from two experimental groups, the nanohorn exposed, and the control mice. Three mice from both groups were sacrificed 24 hours and 7 days after aspiration. Gross examination of the number of macrophages versus activated macrophages in BAL samples from the exposed and the control mice suggested a possible pro-inflammatory response to the carbon nanohorns. Employing a unique detection technique, Scanning Near-Field Ultrasound Holography, carbon nanohorns were discovered bound to cell membranes, inside cells, and near cells in both the red blood cells and BAL sample cells. The positioning of carbon nanohorns inside the cells not bound to a membrane suggests that they entered the cell through a process other than phagocytosis. Furthermore, the red blood cells (RBC) in all the exposed blood samples exhibited a distorted phenotype. Such distortions could possibly lead to various pulmonary diseases. From their ability to permeate membranes, cause pro-inflammatory responses, and distort the phenotype of red blood cells, it can be concluded that carbon nanohorns may pose a biological threat.

Angiotensinogen Expression in Collaborative Cross Offspring. ADAM LUNDQUIST (Christopher Newport University, Newport News, Va, 23606) BRYNN H. VOY (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

The Collaborative Cross (CC) is an emerging population of recombinant inbred (RI) lines of mice designed to untangle complex webs of genetic interactions. The CC, now being implemented at Oak Ridge National Lab (ORNL), is being created from 8 diverse inbred strains of mice bred to produce 1000 RI strains, with every resulting strain containing a portion of the genome from each of the 8 parental strains. The genetic and phenotypic diversity of these 1000 RI strains will model that found in human populations, making the CC a valuable resource for dissecting the genetic contributors to complex traits such as obesity and hypertension[1]. This diversity, coupled with the known genotypes of the animals, will be utilized to map and dissect the genetics of complex traits, which are phenotypes produced from the interaction of multiple genes. We are interested in obesity a complex trait involving many genes interacting within multiple metabolic pathways. One such gene known to play a role in both obesity and hypertension is angiotensinogen, Agt. Agt is a vascular constrictor expressed in adipose tissue; its expression varies widely among the eight CC parental strains. In order to study Agt expression in the intermediate CC generations, those whose genomes have yet to be fixed by inbreeding (strict brother-sister mating for 20 generations), we extracted RNA from adipose tissue, reverse transcribed it into complementary DNA (cDNA), and utilized quantitative Polymerase Chain Reaction (qPCR) techniques to determine mRNA expression levels. Agt expression levels ranged widely (~ 15-fold) across the sampling of CC mice, indicating tha the diversity of this molecular trait in CC mice reflects that of a human population. Our results provide insight into the effects that mixing diverse genetic backgrounds have on Agt expression in these RI mice and will lead to future mapping of genomic loci involved in complex metabolic traits.

Application to Determine and Control Twiss Parameters of the SNS Accelerator Beam. JENS VON DER LINDEN (University of Pennsylvania, Philadelphia, PA, 19104) SARAH COUSINEAU (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

The accelerator ion beam at the Spallation Neutron Source (SNS) is repeatedly focused and defocused by a series of quadruple magnets as it travels to the target to create neutrons by means of spallation. Physicists are interested in characterizing the accelerator beam in order to understand and improve the focusing and transport of the beam. Wire scans are employed to measure the traverse density profile of the beam. With a minimum of 3 distinct wire scans, the ion beam Twiss parameters, which characterize the phase space properties of the beam, can be determined. In this project, a Graphical User Interface (GUI) Application was developed in JAVA to automate the determination of Twiss parameters from the wire scan data files and to determine how quadruples should be varied to change the Twiss parameters at multiple arbitrary locations. The software is coded within the XAL framework, an existing JAVA library developed at the SNS accelerator which is used for all GUI-based physics software applications. A major contribution of the JAVA GUI developed in this project is that it is generally applicable to any area of the accelerator containing a minimum of 3 wire scanners. Existing applications were tied to specific parts of the accelerator. Twiss results can be saved and compared through graphing and averaging. As the SNS is a high intensity accelerator which requires strict control over the beam losses, it is very important that the beam in the accelerator be transported according to the optimum design configuration. Any deviation from the optimum transport configuration can lead to beam loss that can limit the obtainable beam power in the accelerator. This application will aid in measuring the beam state at any point in the accelerator, and will subsequently allow a user to make adjustments to the beam state in order to restore the optimum configuration and ensure well controlled beam transport.

Bending Kirkpatrick-Baez Mirrors for Neutron Focusing. ANTHONY FIELDS and JAY PATEL (South Carolina State University, Orangeburg, Sc, 29117) DR. GENE E. ICE (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

Neutron scattering is useful for analyzing the atomic structure and defect density of materials. Because neutrons have spin, an isotope-dependent scattering cross-section and are penetrating, neutron beams are particularly well suited for the study of magnetic materials, bulk materials and for the study of low Z or mixed Z structures. Several techniques for directing a beam of neutrons to a sample are available. While guide tubes and collimators work well for large sample sizes, focusing becomes increasingly important as the neutron probe dimension and sample sizes become small. The importance of high-performance nondispersive focusing optics for neutrons has just recently been recognized. In micro-focus experiments, we consider the need for convenient wavelength tuning and/or broad bandpass beams. This favors achromatic methods based on specular reflection. The Elliptical Kirkpatrick-Baez (KB) scheme offers the best flexibility and neutron gathering power, and can nondispersively image neutrons to small spots with high intensity and source-limited brilliance. The KB geometry uses crossed mirrors in grazing-incidence. With perfect elliptical KB mirrors, spherical aberration can be eliminated. We have adopted techniques for producing elliptical neutron mirrors by controlled bending. The need to control the slope errors in the mirrors is very important. The mirrors, the bending control mechanism, and supports are integrated as a unit. Both mirrors are attached to, and bent by a leaf spring mechanism. We have used a laser beam to simulate a thermal neutron beam for system calibrations; we determine the radius of curvature of the mirror as a function of bender settings (coupling force). Results show changes in the focal length (and subsequently in the radius of curvature) with micrometer setting. From these results we can determine the optimum radius of curvature of the mirrors for minimum slope errors. The mirror in the vertical plane sags under gravity and therefore, introduces a mixture of defocus and spherical aberration. We have designed passive corrections by a series of springs under the mirror. A computer program has been written to calculate the gravitational curvatures and slope errors as a function of the number of support springs and loading conditions. Simulation results show that the effect of one spring alone reduces the slope errors by a factor of 10 and with three spring supports, slope errors are reduced by over a factor of 100.

Binding Superhydrophobic Powder to Surfaces for Dielectric Purposes. MARY HADLEY (Vanderbilt University, Nashville, TN, 37235) ENIS TUNCER (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

Outdoor insulators used in high voltage transmission lines and substations are constantly under environmental stress leading to power interruptions, flashovers, etc. One common occurrence in polluted areas is excess water collecting on insulators promoting dry band arcing. It has been shown that hydrophobic materials are the solution to avoiding this event. These materials do not interact with water molecules forcing them to bead up instead of collecting into films. This unique surface quality also makes the hydrophobic materials self-cleaning in wet environments. Traditional hydrophobic materials for outdoor insulation have been silicone rubber based materials. Recently other material formulations with fluor based compounds have been proposed. In this study, a superhydrophobic (SH) material made of a glass-based powder is investigated. The material alone does not adhere to surfaces, so research was performed to find a polymer that will bind the particles to a surface while maintaining SH qualities. Test surfaces were prepared by making six solutions of SH powder, a binder, and an alcohol solvent and then dispensing the solution onto plastic and glass slides. Binders tested were polyvinyl butyral resin (PVB), polymethyl methacrylate (PMMA), Rhoplex Fastrack X-tended Seasonal Range resin (XSR), and Araldite resin. Hydrophobicity was tested by measuring the radii of water droplets to calculate contact angles and wettability by recording radii of droplets over time. The surfaces were also observed for scratch resistance, adhesion, and cohesion. Three mixtures showed high angles of approximately 130° to 133°. PVB surfaces had high wettability and poor cohesion, and surfaces made with a higher ratio of binder had poor adhesion. The resin and XSR surfaces maintained some scratch resistance. These tests prove the best surface investigated in this research is made with 0.8g of SH powder and 0.4g of XSR. It repels water for an extended time and maintains the highest contact angle at 133°. This surface is not deemed SH because its contact angle is below 150°, but this mixture is most able to remain hydrophobic. The particle mixture forms a consistent film and adheres well to surfaces, but only fair scratch resistance makes it imperfect for potential application. These results are part of ongoing research to determine polymers that bind to particles and withstand environmental conditions experienced in polluted areas.

Collaboration and Implementation of Disruptive Technologies in the Emergency Response Environment (I-ReSCUE). CARTER DEDRICK (University of Memphis, Memphis, TN, 38105) DONALD E. VINSON (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

Emergency response operation and networks are naturally collaborative in nature; however, due to recent catastrophic events and legislation, these networks have been encouraged to become more centralized. There is ongoing research at Oak Ridge National Laboratory involving the adaptation of existing technologies to National Security solutions. The goals for my part of the project are to describe ways in which beneficial Disruptive Technologies act as a decentralizing force within the emergency response environment on a local level, diagram the overall emergency response environment and propose a theory for an improved planning and response tool. This is accomplished through literature review, interviews, and analysis of current response tools available. Research was conducted to develop theory for an interactive emergency response program to be constructed on an existing platform and explore how Disruptive Technologies can best be utilized. Compartmentalization of resources within emergency response cultures result in slow growth of innovations within the emergency response environment. Research into the connections of these networks is mapped and the ideal response network discussed. Requirements include management of interagency agreements, the ability to expand vertically and horizontally as needed for response to changing events, and include non-profit representatives. Collaboration in emergency response networks is currently carried out, and can be mapped on vertical as well as horizontal axes. The vertical collaboration axis begins with the local EMA (emergency management agency) and expands upward as the events grow larger to include the state and Federal EMA. The horizontal collaboration axis shows the relationship between nonprofit and other NGOs (non-governmental organizations) to the vertical collaboration within the public sector EMA. Collaboration is best facilitated by policies that allow responders to create connections as opposed to those that merely limit abilities. Disruptive Technologies must be embraced and utilized on a wide and daily basis in order to be of any use in the event of an emergency.

Computational Development of H- Ion Sources for the Spallation Neutron Source. JUSTIN CARMICHAEL (Worcester Polytechnic Institute, Worcester, MA, 1609) ROBERT F. WELTON (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

The US Spallation Neutron Source (SNS) requires a high power H- ion source in order to achieve the desired neutron flux. Over the next several years, the SNS will require substantially higher average H- beam current than can be produced from conventional H- ion sources including our baseline source. H- currents of 70-100 mA with an RMS emittance of 0.20-0.35 mm mrad and a ~7% duty-factor will be needed for the SNS power upgrade project. Presently, external antenna sources, based on Al2O3 plasma chambers, have been developed which have been shown to produce beam currents of 25-35 mA with a duty-factor of 2-3%. Computer simulations employing the Finite Element Method (FEM) with coupled fluid dynamic, heat transfer, and thermal stress and deformation capabilities have been performed to investigate the design of the plasma chambers operating at higher duty-factors. These simulations show that a plasma chamber made from AlN can be designed to meet the full duty-factor requirement. In order to meet the beam current requirements, efforts are being made to (i) increase source plasma density by using magnetic confinement and (ii) improve the efficiency of ion extraction from the plasma. Towards these ends simulations are being performed using LORENTZ for magnetic field modeling and COSMOS for thermal analysis of the electron dumping electrode. An AlN plasma chamber, a solenoid confinement magnet and an electron dumping electrode have been designed. It is anticipated that substantially greater beam currents can be achieved with these improvements to the ion source.

Control of Carbon Nanofiber Alignment During Growth in Plasma Enhanced Chemical Vapor Deposition Processes. RYAN PEARCE (University of Tennessee, Knoxville, TN, 37916) MICHAEL SIMPSON (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

Carbon nanofibers are just recently coming under scrutiny with a number of potential uses such as gene delivery arrays and neuronal interfaces. Nanonofibers have a stacked “herringbone” structure, giving them a very high aspect ratio, which is what lends them such a great range of possible applications. Carbon nanofibers are typically grown using a process called “Plasma Enhanced Chemical Vapor Deposition” (PECVD). In this process, a silicon wafer with nickel deposited on it in a specific pattern is placed on a heater in a vacuum chamber. The heat is turned on and ammonia (NH3) and Acetylene (C2H2) are introduced into the chamber at a specific pressure and flow rate. A plasma is induced which causes the carbon from the C2H2 to deposit on the nickel dots, forming the carbon nanofibers. This process forms vertically aligned carbon nanofibers. Our project aims to find a technique to control the alignment of the nanofibers during growth. The way we do this is by changing the method whereby gas is introduced into the system. Classically, the gas flows into the chamber perpendicular to and far away from the surface of the wafer, so that only the ratio of gases affects the growth, and not the flow rate. What we do is place a nozzle directly over the wafer so that the gas flows directly over it. We devise an optimal regimen for growth where we only vary the total flow, keeping the ratio of gases constant. After growth, we observe the wafer under a scanning electron microscope. We have found that nanofibers respond to the variations in flow by tilting along the flow. There are some aspects of this study that require further investigation. First, we need to determine the correlation between angle of tilt and flow rate, which can be done by setting up a series of experiments keeping the total flow variable in a stepped sequence and measuring the resulting angle formed by the nanofibers and the substrate. Then, flow ratio needs to be varied to determine the resulting effects. Another method of creating tilt in nanofibers is through variance in the electric field during PECVD. Towards the edge of the field, this causes the nanofibers to “bend.” This technique is impractical, however, as only the fibers grown on the very edges of the field are affected. Our study is fundamental in understanding how to control nanofiber growth, which will lead to an overall better understanding of nanoscale fabrication.

Cyber Security at Oak Ridge National Laboratory. BOBBY SWEET (Roane State Community College, Oak Ridge, Tn, 37840) VICTO HAZLEWOOD (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

Design for Increased Functionality of the Hot Cells inside the Radiochemical Engineering Development Center. BRENT BEATTY (University of Tennessee, Knoxville, TN, 37916) JEFFREY BINDER (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

The Radiochemical Engineering Development Center (REDC) has been the United States’ main production center for transcurium elements since operations began in 1966. Together with the neighboring High Flux Isotope Reactor (HFIR) these facilities produce transuranium elements for commercial and research purposes. The facilities’ technologies and capabilities gained through a vast production history allow for an ideal test bed for Global Nuclear Energy Partnership’s (GNEP) Coupled End to End (CETE) demonstration. The purpose of the demonstration is to perform mechanical and chemical processes on actual spent nuclear fuel, which will confirm the projected material flow and performance data and with extensive experimental data. While the specialized support infrastructure for hot cell processing has been in place for forty years, there are still design improvements to the current operational flow necessary to fully accommodate all aspects of the demonstration and to enhance future capabilities of the facility to attract new projects. Many of the cubicles have not been updated in several years and were designed primarily for targets and fuel elements from HFIR. The CETE demonstration will be performed on many different fuel pins and assemblies from many reactor designs. In order to accommodate this larger variety of experimental components, I designed and coordinated fabrication of a new "disconnect well" and the associated "containment thimble" for the remote hot cell welder. These modifications will double the length of components that may be processed in the hot cell. This design adds functionality and increases the flexibility required to process the diverse fuel components with minimal impact on the safety specifications and operational requirements and uses materials that did not require new certification for use in REDC. Due to the increased load that will be on the "disconnect well" flange, a calculation was made confirming the ability of the new design to support the added load. The increased moment of the assembly required an updated seismic analysis which was performed and documented in the facility handbook. As the world accepts Nuclear Energy, facilities like REDC have an important and unique role in demonstrating and validating new advanced chemical processes. There are many additional updates and improvements that will have to be made similar to the redesigned "disconnect well" discussed here in order to fully modernize this key facility.

Designing and Implementing Graphical User Information (GUI) Components for the Automation of the Analysis of RTBT Wire Scanners' Data. KARLA WARD (Tennessee State University, Nashville, TN, 37209) TED WILLIAMS (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

Spallation Neutron Source (SNS) located at Oak Ridge National Laboratory (ORNL) is home to the world's highest-energy-pulsed H-ion particle accelerator. The accelerator sends an intense proton pulse to a heavy atomic nucleus of mercury to produce neutron-scattering. Within the accelerator complex are five different sections that work together to result in this neutron-scattering: the linac, the high energy beam transport (HEBT), the ring, the ring to target beam transport (RTBT), and the mercury target. The Linac accelerates the beam to 90% of the speed of light. The HEBT transports the beam from the linac to the ring. The ring stores the protons and the RTBT transports the beam to the mercury target, which gets bombarded by the beam at 60 times per second. The RTBT region of the accelerator is of particular importance currently because this is where data is taken that relate to the size and horizontal and vertical position of the beam before it reaches the target. Wire scanners perform the process of taking the data from the RTBT and placing it into a file to be analyzed, and with the help of a computer program the operators of the accelerator analyze this data. To speed up the analysis of data from the RTBT wire scanners, the analysis program rtbtwizard was modified to improve and enhance the functionality between the user and the data processing routines. Specifically these modifications included the addition of “Cut, Fit and Store All”, “Percent Range”, “Noise Subtraction”, and “Clear Data Table” buttons into an already existing panel. The activation of these buttons produce a series of actions which include automatic Gaussian fitting, storing analyzed data, finding and eliminating the noise floor, and clearing the data table. These modifications resulted in a more efficient procedure for the operators of the accelerator to analyze the size and position of the beam on the target. This in turn improves the probability that there will be a reduction in activation at the target, damage to the nose cone of the target, and ensure maximum neutron production.

Determining the Ability to Monitor the Viability of Transplant Rat Glioma Cells with an Optically Enhanced Catheter. RACHEL DYER (St. Olaf College, Northfield, Minnesota, 55057) BOYD M. EVANS III (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

Approximately fifty thousand cases of Parkinson's Disease are diagnosed within the United States each year. This debilitating disease results from the dissolution of dopamine-dependent communication between the substantia nigra and the striatum of the brain. Cellular replacement therapy, in which stem cells are introduced to supplant dead or stressed cells, has shown promise in animal models. However, the viability of transplanted cells and their survival rate is poorly accounted for by early tests. A novel design coupling a surgical catheter with fiber optic technology provides a tissue delivery platform that can monitor cell viability with sensing techniques widely accepted in the medical industry. The goal of this work is to monitor the health of transplant cells in real time at the final point of delivery using the optically enhanced catheter. Rat glioma cells were separately labeled with CellTracker Orange (CTO) (Invitrogen) and JC1 stain from BioVision’s MitoCapture Mitochondrial Apoptosis Detection Kit and fluorescence was characterized by confocal microscopy. CTO exhibited a single emission peak at 570 nm upon excitation with a 488 nm argon laser. JC1 exhibited two emission peaks corresponding to fluorescence of viable cells and apoptotic cells, 595 and 540 nm respectively. JC1 was used to monitor the viability of cells under apoptotic conditions induced by incubating JC1-labeled cells with carbonyl cyanide 3-chlorophenylhydrazone or etoposide. Observation of fluorescence using a mercury fluorescence microscope over a four hour period demonstrated JC1’s ability to shift in color to reflect cell viability. To detect cell movement through the catheter, cells were labeled with CTO, excited by an argon ion laser with a 501 nm wavelength and a peak emission at 570 nm was detected by an Ocean Optics spectrometer. JC1 was also used to detect the movement and the viability of cells through the catheter. Cells excited by an argon ion laser with a 488 nm wavelength exhibited emission peaks at 540 and 595 nm, demonstrating the ability to detect both viable and apoptotic cells at the final point of delivery. From the detection of rat glioma cells labeled with CTO and JC1 using the diagnostic catheter, and the characterized response of JC1-labeled cells to apoptotic conditions, it can be concluded that these fluorescent probes are suitable for tracking and monitoring the viability of transplant cells through the optically enhanced catheter.

Determining the Optical Properties of Biological Tissue Samples Using an Integrating Sphere Method. MARCUS ALLEGOOD (North Georgia College & State University, Dahlonega, GA, 30553) JUSTIN S BABA (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

Wavelength dependent light interaction with biological tissue can be described using three parameters: the scattering and absorption coefficients and the cosine of the average scattering angle (g). To accurately determine these optical properties for different types of tissue at specific wavelengths would be beneficial for a variety of different biomedical applications. The goal of this project was to take a user defined g-value and determine the remaining two parameters for a specified range of wavelengths. In order to collect the needed data for all the wavelengths in a timely and accurate manner, a fully automated computer program and process was developed. Using a single integrating sphere method, scattered light intensity inside the sphere was recorded via a spectrometer as either transmitted or reflected light from the tissue sample. LabVIEW was used to write programs to collect raw intensity data from the spectrometer, to convert the data into a format for C code execution, and to compute the optical properties based on the collected data. To make the process fully automated, the LabVIEW and C code programs were linked together into one single program to allow data to be passed between the two efficiently. The automated program was tested using a tissue mimicking phantom and determination of the absorption and scattering coefficients showed excellent agreement with theory. Future work and the final phase of testing will entail examining actual biological tissue with known optical properties to check for accuracy before proceeding to utilize the system for its intended purpose. Ultimately, the data collection process and algorithms developed through this effort will be applied to build models for light interaction with biological tissue samples.

Developing a Proof-of-Concept CyberInfrastructure for the USA National Phenology Network. BENJAMIN CROM (University of Tennessee, Knoxville, TN, 37916) BRUCE E. WILSON (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

Phenology is the study of the timing of naturally recurring events, such as flower blooming, particularly those influenced by environmental changes. Phenological measurements are extremely valuable indicators of local, regional, and global climate changes. Further, phenological variations have a variety of crucial environmental and socio-economic implications. Despite this value, broadly distributed phenological measurements are almost non-existent in the USA, in contrast to some European countries. The objective of this work is to explore and evaluate different data models and data management methods needed for the development of the cyberinfrastructure for a new data resource: the USA National Phenology Network (USA-NPN). The USA-NPN will create a national repository for submitting and retrieving a wide range of phenological data, including data from existing research networks and from citizen scientist observers. For this project, we have been focusing on the data model and information management tools necessary to support the citizen scientist aspect of USA-NPN, based on existing work from the Plant Phenology Network (PPN). A key feature at this stage of the program is for citizen scientists to enter phenological observations on any of the 38 species currently in the PPN. The USA-NPN will also require basic tools for observers to retrieve their own data and the publicly available data. We have created a simple but flexible database schema which we are testing against a range of ways the system may be used. This schema is an improvement over the current PPN tools, which use separate text files for each species. We are also working on improving the registration and authentication processes. The user is now able to create login credentials and submit personal contact information without PPN staff intervention. This reduces staff load and the revised data entry forms greatly improve the tracking of data provenance. Our current work will improve session management operations and may enable OpenID authentication. We intend to streamline the maintenance of data submission pages by eliminating the current 38 separate submission pages in favor of one master submission page driven by the underlying database. We will also add a data retrieval page which will give users access to public phenology data. The data offered by this network will contribute to a better understanding of climate change and help engage citizen scientists in climate change science.

Development of 40% Energy Saving Home. JACOB BONAR (University of Tennessee, Knoxville, TN, 37916) JEFFREY E. CHRISTIAN (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

The demand for energy continues to rise throughout the world. One place that everyone can reduce energy consumption is in their home. This is especially true of new homes built with energy efficiency in mind. The goal of my research is to show that a new home can operate with a total energy savings of 40%. The major areas to look closely at are building tightness, appliances installed in the home, and the proper sizing of the HVAC (Heating, Ventilation, and Air Conditioning) system. I will gather the necessary data to prepare a report for the fifth Zero Energy Home, ZEH5. The report concerning only the top floor of ZEH5 will cover how to build a house that has an energy savings totaling 40%. Included in the report detailing ZEH5 will be my write up describing the HVAC sizing using Manual J 8th Edition analysis, which I will conduct for ZEH5. I will work with Jeff Christian to measure and document the airflow rates in ZEH5 distribution system using a flow hood and the whole house air tightness using a blower door. In addition to these sections, an Energy Gauge packet will also be included in the documentation. One major part of the Energy Gauge packet and associated write up will be a comparison between the ZEH5 and the Building America benchmark home. After looking at the energy consumption for a physical year, ZEH5 consumed a daily average of $0.66/day. This is lower than ZEH1-4 homes that consumed between $0.75-$1.01. Two more homes are in development that will continue the research towards a true Zero Energy Home.

Development of a Mathematical Model for Intimal Hyperplasia due to Vascular Injury. NATHAN SUMMERS (University of Tennessee, Knoxville, TN, 37916) RICHARD WARD (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

Intimal hyperplasia (IH) is the thickening of the arterial wall in response to an injury of the blood vessel. IH results from the migration of vascular smooth muscle cells (VSMCs) from the medial to the intimal layer of the blood vessel wall and is believed to be directed by biochemical concentration gradients, a process known as chemotaxis. The primary chemotactic biochemical appears to be platelet-derived growth factor (PDGF) which is produced by platelets adhering to the arterial wall and macrophages invading the intima. The induced migration can be quantified using individual cell tracking or through cell population assays. The parameters for individual cell assays, such as average cell speed and persistence time (the average amount of time the cell takes before it changes direction), can be related mathematically to the parameters of the cell population assays, such as the random motility coefficient (similar to a Brownian diffusion coefficient) and the chemotaxis coefficient (the directed diffusion coefficient). One of the goals of this research was to quantify this relationship using data obtained through literature searches and data obtained from experiments conducted by the Vascular Research Laboratory (VRL) of the University of Tennessee Graduate School of Medicine, Knoxville. However, the needed data from the VRL has not yet been made available, making it impossible to fully quantify the algebraic model for this relationship. It is also believed that the receptors on the cell surface of VSMCs play a key role not only in detecting but also in processing the information from the PDGF biochemical gradient. The second goal of this research was to incorporate VSMC receptor mechanics into a hybrid model (a combination of a discrete model for cellular migration and a continuous model for biochemical diffusion) of VSMC migration driven by chemoattractants. This was accomplished by writing a C++ code modeling the role cell receptors play in the cellular response due to the effect of PDGF. The ultimate goal of this research is to augment a hybrid cell migration model with receptor mechanics to study the possible deleterious affects of balloon angioplasty and the effects of hormone replacement therapy on the outcome of this procedure.

Development of a Visualization Program Used in Computational Simulations of Nanomaterials. JANA BLACK (University of Tennessee, Knoxville, TN, 37916) PETER CUMMINGS (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

Nanoscience offers many scientific opportunities; it also poses significant experimental challenges since it deals with matter in the size range of 1 to 100 nanometers. Theory and simulation are crucial to nanoscience since experimental measurements and observations made at the nanoscale are often impossible to interpret without a theoretical model. Oak Ridge National Laboratory's (ORNL's) Center for Nanophase Materials Sciences (CNMS), in particular the Nanomaterials Theory Institute (NTI), is involved extensively in the development of programs and tools for nanoscale simulations at various time and length scales. NTI maintains a high-performance visualization cluster and 16-node visualization wall in addition to its multi-teraflop computational clusters. The goal of this project is to develop a complex tool that can be used to visualize, at high resolution, the trajectories obtained from various types of molecular modeling such as ab initio, molecular dynamics, or Monte Carlo. The specific data used as an example in this study is from molecular dynamics simulations of pulling apart a gold nanowire. My role in the project is to write a program to drive two major visualization packages which are already installed on the NTI visualization clusters, VisIt and Visual Molecular Dynamics (VMD), so that high-resolution animations can be created from the simulation trajectories. VisIt is designed to visualize very large parallel data in the terascale range. VMD is designed to visualize molecular biological systems. Neither program is ideal for this project, but both encourage users to modify the source code and/or write scripts so the program will better meet their needs. In this particular study, it was considered best to run the visualization simultaneously with 16 copies of either VMD or VisIt, one per node, using 16 sets of simulation data collected at various conditions. I have written scripts to synchronize them. The scripts label the atoms according to their instantaneous temperatures and vividly display the evolution of the system. The visualization helps to interpret the physical process of pulling apart a gold nanowire at the molecular level. This project serves as a trial step in the molecular visualization of complex systems using the NTI facilities; it is one step toward the ultimate goal of developing comprehensive simulation and animation tools of various stages at CNMS to interpret/guide experimental efforts.

Development of an ASTM Graphite Oxidation Test Method. TYLER GULDAN (The University of Tennessee, Knoxville, TN, 37996) TIMOTHY D. BURCHELL (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

Graphite, one of the three allotropes of carbon, is a very useful material because of its unique chemical structure and properties such as mechanical strength, chemical inertness, and electrical conductivity. In order to advance our knowledge of various graphite brands, further research must be conducted to gain a greater insight into the process and effects of oxidation on graphite properties. Although the key processes and controlling elements of graphite oxidation have been identified, the behavior of this material during and after oxidation is not well established. Knowledge of this behavior is crucial in understanding what happens to the various graphite components in nuclear reactors. Thermogravimetric analysis in a vertical furnace of large samples of NBG-18 graphite at the Oak Ridge National Laboratory (ORNL) has been used to characterize the oxidation resistance of this material, and to increase the scientific understanding of the relationship between the rate of oxidation and the flow rates of gases, temperature, and the intrinsic reactivity of graphite. This helps to identify the more oxidation resistant forms of graphite. In addition, comparative analysis of data collected on other graphite materials has been conducted, in order to identify a more expedient procedure for analysis of graphite oxidation data. The information gathered from these experiments and calculations is geared towards the development of an American Society for Testing and Materials (ASTM) test method for the oxidation of graphite. More research on all of the types of graphite is needed, but such results suggest that the current ORNL procedure using the vertical tube furnace may become a reliable ASTM test method.

Development of Integrated PV Reporting System. MARIANO PADILLA (Fullerton College, Fullerton, CA, 0) WILLEM BLOKLAND (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

The Spallation Neutron Source (SNS) at Oak Ridge National Laboratory is a state of the art accelerator-based neutron source. Neutron-scattering research helps develop new materials for superconductors, magnets and plastics. SNS uses a hydrogen ion pulse beam to bombard a mercury isotope target to produce the neutrons. Operators control the accelerator complex by using console screens that can display and set Process variables (PV) from the Input/Output Controller (IOC) devices. Reports on the statistics of the accelerator operation are needed to evaluate the performance of the accelerator. Providing time sensitive and accurate reports of the overall health of the accelerator in an automated, efficient and intuitive manner is an important necessity. The reporting system requirements are to provide an intuitive multi-platform and web-browser based user interface, integration with Oracle, e-mail systems and Portable Document Format (PDF) generation. The reporting system provides the user with a web-based interface to setup specific PVs to acquire, how to process, and how to publish the results. An integrated reporting system is developed using PHP, Java, Javascript, Java Server Pages (JSP) and Business Intelligence and Reporting Tools (BIRT) for ECLIPSE Integrated Development Environment (IDE). The Oracle database already in production use at SNS is the primary storage location for the data collected from the PV’s at a rate up to 1Hz. The integrated reporting system will provide physicists, operators and engineers with a simple platform to monitor, analyze, and report on the operation of the SNS accelerator.

Effect of Chemistry Variations on the Microstructure and Mechanical Properties of Creep Strength Enhanced Ferritic Steels. KEELY WILSON (Michigan Technological University, Houghton, mi, 48128) JOHN SHINGLEDECKER (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

Grades 91, 92, and 122 steels (9-12% Chromium) are known as Creep Strength Enhanced Ferritic steels. These grades of steel are finding increased usage in the pressure retention components of advanced fossil energy systems (Ultrasupercritical Steam Boilers, Heat Recovery Steam Generators, etc.) because of their superior performance in high temperature, high stress environments. The chemical specifications for these grades are very broad, which may affect the mechanical properties and long-term performance of the alloy in service. Ideally in the normalized and tempered condition, Gr 91, 92, and 122, will have fully martensitic structures with no ferrite forming. In an earlier study, two compositions of each grade were produced by varying the amounts of austenite formers (C, Mn, Ni, N) and ferrite formers (Si, Cr, Mo, V, Nb) within the current specification range. These chemistry changes were guided by computational thermodynamics to alter the intercritical temperatures, the temperatures at which steel changes phase, and to cause the formation of ferrite under standard processing conditions. In this study, the mechanical properties of these samples were evaluated, and are compared to literature results for commercially produced material. High temperature (650°C) creep tests were run with loads ranging from 100 to 140 MPa for times exceeding 1000 hours. Tensile tests were run at both high temperature (650°C) and room temperature (25°C). Digital Imaging software was used to analyze the steel microstructures to determine the amount of martensite and ferrite present in each alloy. It was found that both the tensile strength and the creep strength of the alloys decreased substantially with the presence of ferrite in the material. This critical finding clearly shows that the specification range for these alloys is too broad which may result in commercially produced materials with properties far from expectations. A limited evaluation of thermodynamic predictions and microstructural findings was also conducted. The data collected in this study, combined with data from other tests, such as long term creep tests, thermo-mechanical simulation, and thermodynamic modeling will later be used to create more specific standards for Gr 91, 92 and 122 alloys.

Effect of Oxygen Annealing on Substrates for Complex Oxide Film Growth. RYAN SMITH (Case Western Reserve University, Cleveland, OH, 44106) HANS CHRISTEN (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

In this investigation, the optimum annealing conditions (temperature and atmosphere) yielding atomically flat surfaces on the crystalline material NdGaO3 were examined. This material is used as substrate for thin-film pulsed laser deposition (PLD) of various complex oxide films, including, for example, Yttrium Barium Copper Oxide (YBCO), a high-temperature superconductor (HTSC) based on the perovskite crystal structure. Since their discovery over 20 years ago, HTSCs have been thoroughly investigated because they exhibit superconducting properties (zero resistance) above the boiling point of liquid nitrogen (77 K). Thin films of these materials have shown improved superconducting properties, which are highly dependant on the defect structure of the film. Recently, new complex oxide substrates for YBCO deposition have been investigated, including LSAT ((La,Sr)(Al,Ta)O3) and NdGaO3, because of their similar thermal expansion coefficient, good dielectric properties, and small lattice parameter mismatch with YBCO compared to traditional sapphire substrates. Such a perovskite substrate with atomically flat terraced surface terminated in regular unit-cell high steps is essential for high quality epitaxial YBCO films with low or controllable defect density and optimal superconducting properties, as well as for other metal-oxide films (ferroelectrics, colossal magnetoresistive (CMR) materials, etc.). Perovskite-type ABO3 crystals with at least two cation species, like NdGaO3, can terminate in either “A-site” (AO) or “B-site” (BO2) layers on the crystal surface. Unlike most substrates considered for oxide film growth (e.g. SrTiO3), thermal annealing of NdGaO3 results in an A-site layer termination. Studies of YBCO film deposition have shown that A-site layer termination prevents the segregation of deleterious copper precipitates, and thus such substrates are highly desirable for HTSC growth. Single crystal (001) NdGaO3 substrates were thus annealed in air and oxygen, and the resulting surface morphologies were investigated by atomic force microscopy (AFM). The optimum annealing conditions for annealing were found to be 1100 °C for 1 hour in an argon (or other inert gas) atmosphere, although annealing in air yields acceptable results.

Elaboration on the Hexagonal Grid and Spiral Method for Data Collection via Pole Figures. ANTHONY RIZZIE (Ball State University, Muncie, IN, 47306) THOMAS WATKINS (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

A pole figure provides a representation of the distribution of a particular set of atomic planes for data acquired through diffraction and is used for analyzing crystallographic texture or preferred orientation. Pole figures are constructed from a collection of data points, each with a prescribed azimuthal angle (phi) and sample tilt angle (chi) (as specified by the goniometer) and measured intensity (counts or counts per second). Traditionally, the Schulz method (5°x5° grid) is employed to acquire the necessary data, but this leads to a high concentration of data points for small chi values, low concentration for large chi values, and consequently an inefficient use of time. Two alternative data collection methods, the hexagonal grid and spiral, have been previously proposed but only tersely documented in terms of both construction and implementation. The goal, therefore, is to provide a practical description of the mathematics required to implement the hexagonal and spiral data collection schemes. Applying the concepts of equal area and stereographic projections and geometry, spreadsheets were created to formulaically develop hexagonal and spiral grids, which are then related to angular movements of the goniometer. Using the generated data points, the hexagonal grid and spiral methods were programmed by “brute force” into the existing x-ray software and employed to collect data for a sample of aluminum foil. The resulting (111) pole figures compared favorably to typical rolling textures for aluminum foil collected with the conventional Schulz method. The hexagonal grid has been shown to reduce the number of data points and time needed to complete a pole figure, while providing equal area sampling. The spiral method was shown to use only a quarter as many data points as the 5° x 5° grid. In the future, LabVIEW software will be utilized to develop programs for collecting data using both the hexagonal grid and spiral methods and then convert the data back to the conventional 5° x 5° grid.

Electrolysis of Saline for pH Control and Oxygen Production. ANNA BESMANN (University of North Carolina at Asheville, Asheville, NC, 28804) ELI GREENBAUM (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

Diabetic retinopathy is a disease which causes small, fragile blood vessels to form within the retina to compensate for the normal blood vessels’ inability to bring sufficient oxygen to the eye. These blood vessels are prone to hemorrhaging in the eye, causing temporary or permanent blindness. To help stop this problem before the small blood vessels can form, electrodes can be implanted into the eye to stimulate the production of oxygen in the vitreous humor. However, this also induces the formation of free chlorine, which causes the vitreous humor to become more alkaline. In order to keep the pH at a manageable level, an anode and a cathode can be implanted into the vitreous humor while a second anode connected to both electrodes by a sidearm can be implanted behind the ear. Protons will pass back and forth along the sidearm, keeping the vitreous humor from becoming too acidic or too alkaline. Alternating between both configurations keeps the pH stable, as the internal electrodes cause a rise in pH while the sidearm electrode causes a drop in pH. In these experiments, two electrodes were put into the buffered saline itself and a third electrode into a glass sidearm filled with saline solution. To counter the problem of excessive baseline pH shift, a 2 mM solution of phosphate buffered saline (PBS) was used instead of pure saline. The solution was sparged at 25ml/minute and heated with a water bath to 37°C to simulate the fluid motion in the vitreous humor and temperature of the human body. A DC charge of 800 µA was applied to the electrodes to stimulate the production of oxygen and a change in pH. The internal electrodes were used in three minute increments until the pH had moved one pH unit above the baseline, then the sidearm electrode was used in 1.5 minute increments to bring the pH down 2 units. Afterward, the internal electrodes were used to bring the pH back to the baseline. However, the exact amount of time needed to reach the acceptable limits of high and low pH was variable, and on occasion use of the internal electrode after using the sidearm electrode for a long period of time caused the pH to drop for unknown reasons. The next step of this process would be to repeat the experiment with a solution that is more like the vitreous humor of the eye, and eventually move on to implanting the electrodes within an actual eye.

Elevated atmospheric [CO₂] concentrations do not alter net nitrogen mineralization rates in a [CO2] enriched sweetgum forest. CAITLIN GUTHRIE (Pomona College, Claremont, CA, 91711) AIMEE T. CLASSEN (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

Carbon dioxide concentrations ([CO₂]) in the atmosphere have increased by 36% in the last 250 years. Previous research has demonstrated that elevated levels of atmospheric [CO₂] can increase plant production. However, to maintain an increased level of growth, trees must acquire higher levels of soil nutrients. Thus, nutrient availability might ultimately constrain the response of forests to elevated [CO₂]. In particular, nitrogen (N) often limits plant production in terrestrial ecosystems, and understanding how soil N cycling responds to elevated [CO₂] in forests will enable scientists to make better predictions of how forests will respond to climatic changes in the future. I took advantage of a long-term experiment at Oak Ridge National Laboratory (ORNL) manipulating atmospheric [CO₂] to test the prediction that elevated [CO₂] would decrease net N mineralization. Net N mineralization is the amount of N that microbes have transformed from an organic form to an inorganic form that is available to plants (minus the N taken up for use in microbial biosynthesis). The ORNL, Free-Air [CO₂] Enrichment (FACE) facility was constructed on a sweetgum plantation planted in 1988. There are five 25-m rings (two elevated rings where the target concentration is 550 ppm CO₂, and three ambient rings) and the treatments have been running since 1998. I inserted N mineralization soil cores into each of the rings in June and July, 2007, and let them incubate for 30 days each. Results indicate that there is no difference in net N mineralization rates, net N nitrification rates, or leaching between elevated and ambient plots. However, there was a significant decrease in net N mineralization rates for both treatments from June to July. These results may indicate that increased forest production under elevated [CO₂] has not altered the net amount of N available for tree uptake at ORNL FACE. Alternatively, the lack of response to elevated [CO₂], and concurrent temporal response could reflect the low levels of precipitation (the third lowest on record since 1895) observed over the course of this study. More work is needed to illuminate the effects of elevated [CO₂] on soil N cycling and its effects on forest production at this site.

Energy, Carbon and Climate: Projections to 2025. ALISON ERLENBACH (University of Florida, Gainesville, FL, 32601) T.J. BLASING (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

Energy demands and associated carbon emissions in the U.S. are expected to increase in the foreseeable future. Policies to reduce fossil-fuel consumption and carbon emissions must consider present and future energy needs, and fuels available to most economically meet those needs, both of which show appreciable inter-regional differences. The National Energy Modeling System (NEMS), a product of the Energy Information Administration of the U.S. Department of Energy, projects this growth based on various economic factors for the country as a whole, and within each of the nine census divisions of the country. In this study, we summarized output from the NEMS for each census division, including projected regional carbon emissions which we calculated based on NEMS-projected energy statistics. To consider climate-change effects on energy demand, we used the results of an earlier study in which a Parallel Climate Model-Integrate BIosphere Simulator (PCM-IBIS) was used to drive the NEMS using different climate change scenarios. Base-case (no climate change) projections show varying increases in energy consumption and carbon emissions for each region, as their populations increase at varying rates. Carbon emissions do not increase proportionately to energy demands, but instead depend on the fuel types each region uses, and is projected to use, as well as the proportion of energy supplied by electricity. Electric generation is inherently an inefficient use of thermal energy; only about one third of the thermal energy produced can be converted to electricity. The remainder is identified as "electricity-related loss" in the NEMS. Approximately 20% of U.S. carbon dioxide emissions result from this "lost" thermal energy. Effects of simulated climate warming, compared to the base case, were to decrease national energy demand. However, projected carbon emissions increased because reduced carbon from heating was outweighed by the increase in carbon emissions for electricity used for cooling. Regional carbon emissions increased at varying rates, being heavily dependent on the fraction of energy that is electricity and on the fuel types used to generate electricity. Policies to mitigate carbon emissions should consider regional differences in projected demands and in economically available fuels, as well as differences in regional potentials of renewable energy sources and of technologies that reduce wasted thermal energy.

Enhancing Network Security by a Centralized and Standardized Dynamic Event Log Data Collection Method. MARK SEAL (Walters State Community College, Morristown, TN, 37813) DON WILLIAMS (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

Heat-Reflective Paint for Deck Surfaces of Naval Vessels. EMILY OTTENWELLER (University of St. Francis, Fort Wayne, IN, 46808) RICK LOWDEN (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

The new V-22 Osprey aircraft has the capability to vertically take off from and land on the deck of an aircraft carrier. During take off and landing, the hot exhaust from the Osprey aircraft engines impinges directly onto the deck of the ship. The deck surfaces were not designed to handle high temperatures and thus warp from the excess heat. Insulating paints that use special ceramic additives have been developed to improve the energy efficiency of buildings and structures. The decks of naval vessels are coated with paints that include ceramic grit to make them non-skid. It was hypothesized that the insulating additives could be used to replace the non-skid grit and create a paint that could protect the deck from the hot exhaust. Ceramic particles were added to an epoxy-based surface coating to alter the layer’s thermal properties, i.e. to reflect, absorb or conduct heat. The ceramic additives include Bionic Bubbles which are hollow microspheres derived from fly ash, Insuladd particles which are hollow ceramic mircospheres invented by NASA, and silicon carbide platelets. The test specimens were ½ inch thick steel plates to which paints with different additives were applied. The plates were heated using a heat gun to simulate the exhaust of the aircraft and temperature distributions on the backside of the painted specimens were measured. The temperature distributions for the plates coated using paints with additives were compared to results for bare metal, paint with no additive, and the standard non-skid deck coating. The plate with the highest concentration of Bionic Bubbles was the most effective in reducing the temperature of the plate; however, the layer is likely too fragile for the application. The deck coating must not only be insulating but also robust and non-skid. It appears that the ceramic additives will need to be modified to best suit the needs of this application.

Heavy Truck Duty Cycle Data Collection. FIONA DUNNE (University of California, Santa Barbara, Santa Barbara, CA, 93106) GARY CAPPS (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

Real-world data on Class-8 truck operation is necessary for fuel efficiency studies as well as for use in vehicle powertrain design software. To gather this data, six Class-8 trucks were instrumented with a data acquisition system (DAS) and a set of sensors to monitor numerous vehicle performance parameters from engine to tires, as well as weather conditions, road slope, and load weight over a one year period. First, the truck's J1939 vehicle network was tested to learn what vehicle performance information was available on it, and how to retrieve the data of interest. The other sensors and DAS were then installed on each truck, and all data was recorded to the DAS as the trucks then continued in regular operation. During operation, data was checked weekly for errors to determine whether the equipment was functioning correctly. By checking the data, it was discovered that weather sensors began failing from water entry due to unexpected pressure washing of the trucks. Load weight data was found to be inaccurate, as truck drivers had not correctly calibrated the weighing system. Road slope and vehicle network data results were as expected. It was concluded that weather sensors should be covered during pressure washing, and an alternative method for calibrating the weighing system was devised. It was also concluded that the method used to obtain road slope, a derivation from GPS vertical and ground velocity data, was adequate. Finally, it was determined that no changes needed to be made in the method of communication with the vehicle network. Data will continue to be checked for errors throughout the remainder of the one year test, and changes will be made as necessary.

Hydrodynamics of a Centrifugal Contactor. MEECKRAL WILLIAMS (Prairie View A&M University, Prairie View, TX, 77446) DR. COSTAS TSOURIS (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

Countries producing nuclear energy have an interest in nuclear fuel reprocessing, a chemical procedure that extracts fissile materials such as uranium-233, uranium-235, and plutonium-239 from fission products and other materials in the spent nuclear reactor fuels. The goal is to recycle materials that are useful for further nuclear energy production. Centrifugal contactors are used in many plants for the reprocessing of fissile materials. By the use of centrifugal force, the contactor has the advantages of intensive mixing, rapid phase separation, and chemical separation by liquid-liquid extraction in a single unit operation. Two immiscible fluids of different densities, usually an aqueous and an organic fluid, are fed into the contactor to obtain two-phase mixing and extraction. The objective of this work is to determine flow patterns and dispersion properties, such as drop size distributions, in a four-inch diameter centrifugal contactor. The two fluids used here are water and dodecane at flow rate ratios ranging between 1:5 and 5:1. The total flow rate is on the order of 600 mL/min, and the agitation speed is up to 3600 rotations per minute. Once the dispersion is formed, a sample is taken into a light scattering cell where cetyl trimethyl ammonium bromide (CTAB) solution is initially located. The CTAB is a surfactant that stabilizes the droplets to prevent coalescence. Results of particle size measurements obtained by the LS130 light scattering instrument from Coulter have shown that only small droplets can be measured by this method because large drops escape fast to the top of the cell due to buoyancy, even though the sample in the cell is stirred. Video photography using a camera that operates at fast shutter speed and frame recording was employed to visually observe the dispersion in the contactor through an optically transparent wall. Video images reveal details of the drop size, air bubble entrainment, and flow dynamics of the mixing zone. Video imaging has the advantage of direct visualization of the droplets; however, the disadvantage is that it is difficult to distinguish bubbles from droplets. It is hypothesized that, because the difference in the refractive index is greater for air and water or dodecane than for water and dodecane, air bubbles appear sharper on the video images. Drop size measurements are obtained from the images through a size calibration procedure. The size of drops ranges between 1µm and 500 µm.

Imaging Diagnostic Systems for the Spallation Neutron Source. KATHLEEN GOETZ (Middlebury College, Middlebury, VT, 5753) TOM SHEA (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

Since the start of commissioning, imaging beam diagnostics have been utilized widely at the Spallation Neutron Source (SNS) as quick intuitive diagnostic measures and for the calibration of other diagnostic instrumentation. Because other imaging systems such as the Video Foil Monitor proved indispensable, there was a drive to create new systems such as the temporary Target Viewscreen (TVS) and the Small Angle Neutron Scattering (SANS) Neutron Beam Stop Monitor (NBSM). My work on the TVS was performed over 3 semesters, with this summer’s focus being on system documentation. Although the temporary TVS, a system that my mentor and I designed and implemented, has already served its purpose and has been decommissioned, my work on the project continues in the form of a paper and presentation at the International Accelerator Applications conference that was at the end of July 2007. I am also part of a team that is working on plans for a second generation Target Viewscreen to be implemented next year. The NBSM is a new project with initial design work to be completed by the end of August 2007. Earlier this summer, I performed calculations to estimate the light that will be collected by the second generation TVS and NBSM optics. Presently, my work on the NBSM includes an as yet to be completed experiment at HFIR to look into the types of optics required for a successful system. I am also currently designing the experimental set up.

Implementing Optimized and Scalable Non-Standard Matrix-Multiply Algorithms. RANDY HASSELL JR. (Old Dominion University, Norfolk, VA, 23455) RICHARD BARRETT (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)

Matrix-Multiplication is the fundamental operation for solving several algorithms including other linear algebra operations like matrix inversion, systems of linear equations, and matrix determinants. It’s also used in computer graphics and digital signal processing. The Computational Materials Science Group at the Oak Ridge National Laboratory (ORNL) is developing a large-scale computer application that studies the fundamental properties of materials. The performance of this materials science code relies heavily upon the execution of matrix-multiplication. The dimension of the matrices are 32 x N, where N is currently 4K, and continues to expand to 40K. The purpose of this project is to create an optimal algorithm that performs matrix-multiplication, and to research the implem

Student Abstracts at ORNL: