Student Abstracts: Engineering

A Comparison between Sludge Sedimentation Rates and Dispersion Characteristics of No2 Oil and Biodiesel. CHRISTOPHER BROWN (Clarkson University, Potsdam, NY, 11787) THOMAS BUTCHER (Brookhaven National Laboratory, Upton, NY, 11973)

Biodiesel made to American Society for Testing and Material (ASTM) standards, D6751, is a renewable fuel source that within the fuel industry is criticized as being a solvent. When blended with petroleum-based fuels in tanks with contaminants such as carbon deposits, the Fatty Acid Methyl Esters (FAME or biodiesel) are accused of introducing contaminants into solution with the fuel. This leads to filter plugging and fuel starved equipment. In order to attain a greater knowledge of the fuel solvency characteristics of biodiesel, data was collected from testing sedimentation rates, particle size and particle distribution. To test sedimentation rates, clean fuel samples of biodiesel and No.2 oil were thoroughly mixed with sludge (carbon deposits from No.2 oil tank bottoms). After being uniformly mixed, each fuel sample was allowed to settle for set time intervals, and then centrifuged. To measure particle size and distribution a laser based optical probe measured the chord length of particles and distribution of particles in solution. When reviewing the sludge particle sedimentation rates, it was evident that the particles required a greater period of time to settle out of the biodiesel fuel sample compared to the No. 2 fuel oil sample. Furthermore, although the settling rate is longer for biodiesel, the same amount of sediment precipitated from the fuel. When analyzing the results from the laser based optical probe, the particle chord length and particle distribution was identical when comparing biodiesel to No. 2 fuel oil. The results that have been gathered imply a significant breakthrough on the industries diagnosis of biodiesel’s solvency. The data suggests that biodiesel has the same solvency characteristics as no. 2 fuel oil and that biodiesel is a better dispersant. Biodiesel disperses the sediment particles in the fuel and suspends them longer than No.2 fuel oil, allowing the contaminants a greater amount of time to be carried to the fuel filter. This finding will allow any necessary changes to be made to in-line fuel filtration.

A Networked Control/Data Acquisition System Based On The ColdFire Microprocessor. ILYA SUKHANOV (State University of New York at Stony Brook, Stony Brook, NY, 11794) EDWARD KISTENEV (Brookhaven National Laboratory, Upton, NY, 11973)

Nose Cone Colorimeter Control (N3C) is a highly dynamic system used for slow data acquisition (DAQ), remote system control, and environmental monitoring. The N3C project utilizes an embedded ColdFire processor with the Quadros real time operating system (RTOS) which acts as a bridge between an array of hardware devices and remote-controlling machines over the TCP/IP network protocol. The requirements of this project were to build a network-capable device to program field-programmable gate array (FPGA) devices such as Xilinx and Altera. While such network-FPGA-programmers are available on the market they all only do one task, our specification called for a way to interface with other buses of the system and DAQ. N3C utilizes the feature rich ColdFire microprocessor which allows for easy access to a number of buses such as I²C, QSPI, UART, JTAG and GPIO. With the help of the N3C client one can quickly develop custom tools to remotely interface with devices via these buses. In the case of the Nose Cone Colorimeter, N3C is used to interface with most of the buses supported by ColdFire, JTAG is utilized for FPGA configuration and the systems slow control, I²C as a bridge to a Dallas 1-Wire bus which in turn is used for environmental monitoring and control, QSPI for slow DAQ read out. The N3C system is controlled via a simple control protocol over TCP and data-stream is transferred over UDP to reduce the network overhead at the cost of reliability. During the course of this project we've optimized Quadros RTOS supplied TCP/IP stack (a modified OpenTCP implementation) for our applications resulting in a ten-fold performance increase. This optimization makes it feasible to use N3C as a slow (2MBytes/s) DAQ system. For further improvement we plan to implement a compression schema into our DAQ system. While we have only tested compression on a desktop machine the results are promising. Utilizing a variant of Hashemian coding described in the paper entitled “Condensed Table of Huffman coding, a New Approach to Efficient Decoding” by Reza Hashemian, it is possible to compress data just as well as with Huffman coding but decompression requires less memory and time. Built with flexibility in mind, N3C was developed to work on two versions of the ColdFire processor, the MCF5282 and MCF523x. Such flexibility allows for easy integration of new features and utilization of this system in projects other than the Nose Cone Colorimeter Upgrade.

A New Routing Protocol for Connectivity in Ad Hoc Networks. TYLER KARRELS (University Of Wisconsin - Madison, Madison, WI, 53703) SAMI AYYORGUN (Los Alamos National Laboratory, Los Alamos, NM, 87545)

TCP/IP routing is the standard for static wired networks, but TCP/IP cannot quickly adjust to changes in network topology that can occur in wireless ad hoc networks. A wireless ad hoc network's topology is dynamic because hosts eventually lose power, hosts' transmission ranges may vary over time, hosts may become damaged, or hosts may enter or exit the network's transmission range. These problems require new routing paths to be established to maintain network connectivity. The purpose of our research at Los Alamos National Lab (LANL) is to improve, or at least maintain, connectivity between hosts even when the network topology is drastically altered. We propose a new routing protocol called Neighbor Monitoring (NM) that creates multiple paths to the network sink and monitors these paths to decide which is optimal. Network simulations have been conducted in Matlab using a simulator developed for this research. For a comparison to existing routing algorithms, Dynamic Source (DSR) and Load Balance (LB) routing algorithms have been implemented in addition to NM routing. Simulations are being run with networks of varying size and topology. The three topologies used are grid, random, and degree based. Preliminary results for small networks have shown that DSR and LB algorithms perform better than NM in a grid network topology and no node failures. It is expected that NM routing will be more resilient by quickly repairing routes. It is also expected that NM routing will establish quicker routes even when a network is heavily loaded.

A Piping Flow Diagram: Verifying the Nitrogen Supply System for Argonne National Laboratory Building 212. SOPHIA PAN (Swarthmore College, Swarthmore, PA, 19081) ELIZABETH GROM (Argonne National Laboratory, Argonne, IL, 60439)

There is a significant need to maintain accurate records for configuration management of nuclear facilities at Argonne National Laboratory. Building 212 at Argonne National Laboratory contains the Alpha-Gamma Hot Cell Facility that is presently used to handle and process radioactive material. An important aspect of creating safe working conditions is the maintenance of an inert atmosphere within the hot cell, due to the storage of pyrophoric material. This project involves the verification and updating of the system schematic for the existing safety-significant nitrogen supply system piping and valves showing the flow of nitrogen into Building 212 as well as for an H-wing as-built document of the nitrogen storage tanks and vaporizers. The updated nitrogen flow schematic includes drawings of pipe lines, the numbered valve system, which controls the flow of nitrogen gas into the building, and two nitrogen tanks—a main and auxiliary tank—that hold the nitrogen supply. The H-wing as-built includes the two nitrogen tank plan views as well as two detailed elevated views. When the updated schematic and H-wing as-built are approved, they will be added to the Document Control Center archives in Building 214. It is important to keep careful records of system as-built diagrams for routine maintenance, system updates, or in the event of an emergency at the laboratory.

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.

Acoustic Array for Wind Turbine Noise Analysis. CHRISTOPHER BONILHA and IAN TSE (Univeristy of Colorado, Boulder, CO, 80309) PATRICK MORIARTY (National Renewable Energy Laboratory, Golden, CO, 89401)

Locating and characterizing sources of noise from wind turbines can greatly aid in the design and production of quieter, more publicly accepted machines for renewable power generation. An acoustic array is a device comprised of an arrangement of microphones that when coupled with an algorithm, can locate sources of noise. In 2006, The National Renewable Energy Laboratory (NREL) partnered with the University of Colorado at Boulder to construct a prototype acoustic array as a proof of concept. Issues arose in both the original hardware and software components which needed troubleshooting and correction before the capabilities of the array could be determined. Tests showed that erroneous signals being outputted by the array were caused by the original data acquisition (DAQ) hardware’s inability to handle the high volume of data samples. A robust, differential-referenced, simultaneous-sampling DAQ was purchased to replace the old DAQ, resolving the data acquisition issues. The low-quality microphones had inconsistent frequency responses that contributed to the erroneous results. It was also determined that the signal-to-noise ratio could be significantly improved with better microphone arrangements and with the doubling of the number of microphones on the array. The beamforming algorithm that computes the sound pressure levels emanating from a given plane of interest was originally written incorrectly and very inefficiently. A new program was written to perform the beamforming algorithm on the recorded audio signals and produce plots to facilitate easier analysis. Simulations were performed to analyze how array parameters contribute to the performance of the array. After hardware upgrades and the software revisions, the array was subjected to a series of simulations and tests to determine its capabilities. The array was unable to detect a monopole sound source roughly 4 meters away. Further tests should be done on an array with more microphones of better quality and also with a source that is both louder and positioned at probable turbine location.

Air Filter Pricing Analysis for a Business to Business or Indefinite Quantity Agreement (Alternative). MATTHEW HARDMAN (University of Idaho, Moscow, ID, 83843) DALE SCHIELKE (Pacific Northwest National Laboratory, Richland, WA, 99352)

As the number and breadth of the facilities under Pacific Northwest National Laboratory (PNNL) control increase, the need and importance of cost estimates for maintenance of these facilities also increases. As with any business, the cost to maintain operation of its facilities can be a daunting task. The price analysis on air filters for a 'cutting edge’ research facility such as PNNL is difficult to achieve since many non-traditional, higher rated filters are needed. In response to the growing difficulty in managing many systems, electronic databases complete with inventories, work orders, preventative maintenance, and purchasing capabilities are being built. One such program which the Facilities and Operations Directorate (F&O) at PNNL uses is MAXIMO, developed by mro software. MAXIMO contains a purchasing capability which can be set up with a business to business (B2B) agreement or indefinite quantity (IDQ) agreement. A B2B agreement is a contract between two businesses for the sale of products directly between the two entities. PNNL wants to set up a B2B or IDQ agreement for air filters as a pilot for using the full capabilities of MAXIMO purchasing capabilities in the future. Using MAXIMO report capabilities, descriptive reports were made for all air filters currently used at PNNL. Microsoft Excel files were then produced and sent out to previous vendors for pricing information. After gathering the pricing information into files, the information was then entered into MAXIMO. These files along with inventories were compared to determine which filters were eligible for excessing. Once the excessing was underway, work on a B2B began. If requirements for a B2B cannot be met, an IDQ will then be set up. This work towards a B2B or IDQ will help create a system in which filters are ordered for "just in time delivery". This kind of system will help with storage costs since not as many air filters will need to be stored on a regular basis. Overall, implementing a B2B or IDQ system will reduce cost and increase the efficiency of the maintenance work, therefore saving money, on mechanical systems here at PNNL.

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.

AirMagnet System Installation: Securing and Assuring the Advanced Photon Source Wireless Network. MARYA PEARSON (Norfolk State University, Norfolk, VA, 23504) KEN SIDOROWICZ (Argonne National Laboratory, Argonne, IL, 60439)

Using a wireless network in a government research enterprise raises concerns of security breaches, signal interference, and internet connectivity. Initially, the wireless network at the Advanced Photon Source was vulnerable because efficient managing tools were not available. The AirMagnet system, manufactured by AirMagnet Incorporated, is a security software utility which provides a secure overview of the wireless network. New AirMagnet technology detects and reduces wireless vulnerabilities at the APS through a system of monitoring software and spectrum sensors. Following the system’s installation on the APS site, spectrum evaluations were conducted to gather information on the network’s performance. AirMagnet’s survey-planner feature was used to scan the ring and each floor of APS for radio frequency signal data. In response to user complaints of poor internet connection, spectrum analyzer and laptop analyzer were enabled to identify devices that were affecting the wireless signal. The survey-planner’s RF signal distribution prompted adjustments to the signal strength and the access point channel allocations. Information gathered using spectrum analyzer and laptop analyzer implicated unknown rogues and channel interference affecting the network. In addition, the programs offered troubleshooting solutions for each alarm. Subsequently, the spectrum evaluations improved the wireless network environment. Using the AirMagnet system as an administrative tool minimized speculation and time-consuming tasks related to network problem-solving.

Alternative Fuels Data Center: Fleet Reports, Databases and Website Redesign. BRETT HOAG (University of Colorado, Boulder, CO, 80309) JOHANNA LEVENE (National Renewable Energy Laboratory, Golden, CO, 89401)

The Alternative Fuels Data Center (AFDC) is online collection of data, including more than 3,000 documents and several interactive tools. The AFDC collaborates with the U.S. Department of Energy’s (DOE) Clean Cities Program as well as the Energy Policy Act of 1992 (EPAct) fleet programs. Federal fleet location reports for EPAct were processed using excel, geocoding software and cgi scripts that evaluated the received data to the data located in the AFDC (AFDC) Alternative Fuel Station Locator Database. A total of 15,267 unique fleet locations were processed resulting in an addition of 73,841 vehicles to the AFDC Database. The updating process of the Related Links Database used several different debugging procedures and techniques, as well as work with Oracle database maintenance software. The Clean Cities Success Stories Database update process required extensive work contacting organizations, writing and editing summaries about organizations that are currently implementing alternative fuels within their fleet. During the updating process 131 individual organizations were contacted, resulting in a new Success Stories Database that had 15 new organization summaries as a base. Debugging procedures and techniques were also applied to several online tools available for fleets as well as the public. The Make/Model Application, Flex-Fuel Fleet Vehicle Cost Calculator and the AFDC Laws and Incentives page were debugged for potential problems that new users may experience. The research was conducted to aid in the development of the new AFDC website that has a planned launch date of September 30, 2007.

An Assessment of the Implications of 10CFR851 on the Vacuum Systems at the National Synchrotron Light Source. MICHAEL ESPINOZA (State University of New York at Stony Brook, Stony Brook, NY, 11790) ED HAAS (Brookhaven National Laboratory, Upton, NY, 11973)

As of February 9, 2007, the U.S. Department of Energy required that its’ facilities are compliant with Section 10 of the Code of Federal Regulations, part 851 (10CFR851). One of the new rules is the requirement to treat vacuum vessels as pressure vessels due to their susceptibility to backfill pressurization. The consequence of treating vacuum vessel as pressure vessels is that they must potentially comply with the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel (B&PV) Codes which formerly were not used for vacuum systems, specifically Section VIII of the B&PV code. At the National Synchrotron Light Source, electrons circulating in the accelerators produce photons in the beam lines for research. The electrons and photons are contained within vacuum chambers and beam pipes. Most beam line segments having sources of pressure, such as water or a gas, and were inspected to see if added safety devices were needed. If needed, ASME-compliant safety devices shall be identified, sized, and located according to ASME code. All of these codes are divided into smaller sub-sections, in which only some are applicable to vacuum systems. These codes require safety pressure relief devices on vessels where over-pressurization could result in a failure mode. After developing and programming the necessary equations using Excel spreadsheets, a study of each beam line was undertaken. Of highest concern were pressure sources that penetrated into the vacuum space within components such as monochromators, slits, and beryllium windows. Cooling water sources connected to make-up water, nitrogen, helium, and process gas sources were examined and the pressure and flow information was calculated. Each isolatable section with a potential pressure source required a pressure relief device. Within each segment, the weakest component was generally identified. Glass view ports and beryllium windows for example were usually the components which would be expected to fail at the lowest internal pressure. The spreadsheet calculated the pressure relief requirements and output graphs of flow rate and pressure verses time. This effort assures that NSLS is compliant with 10CFR851 and its vacuum systems are safe.

An Ergonomics Guide to Pipette Selection and Use. MONICA LICHTY (University of Michigan, Ann Arbor, MI, 48109) IRA JANOWITZ (Lawrence Berkeley National Laboratory, Berkley, CA, 94720)

The ergonomics of laboratory environments has not been developed as thoroughly as that of computer workstations and there is not much current guidance on ergonomics attributes of common lab equipment for the scientific community. This means that scientists and technicians are in great danger of developing upper extremity cumulative trauma disorders (CTDs) such as tendonitis and carpal tunnel syndrome from their regular activities. The focus of this project was on providing a usable guide to pipette and pipet controller selection for the employees at the Lawrence Berkeley National Laboratory (LBNL) to facilitate purchasing decisions and reduce the rate and severity of injuries associated with manual pipetting. The first step in the development was to become familiar with the pipette models that are commercially available. Interviews were conducted to learn which qualities of a pipette are important to users. Insight was also gained into the ways in which pipettes are held and operated through observation. Once a final list of attributes was determined, meetings were held with pipette manufacturer representatives to obtain demonstration products for assessment and to learn about the different product lines. The main quantitative measurements were: weight, plunger force, tip ejection force, blowout force, maximum thumb displacement, girth, and overall length from the thumb support to the end of the tip ejector sleeve. Other qualities were recorded such as autoclavability, electronic program options, and charging method of the pipettes. A section of comments was developed based on user input and ergonomics factors including handle comfort, display legibility, and ease of volume adjustment. The guide will be available in two versions. The quick reference guide is comprised of product ratings in a variety of categories including weight/balance, grip comfort, and control forces. The extended user guide includes all of the quantitative information obtained as well as free-form comments about the products. Both versions of the guide will be available online to all employees of LBNL. The guides also come with a set of tips on posture, workstation layout, and task design to address the task as a system of interacting factors rather than solely a tool design issue. Although the guides provide an increased level of assistance to consumers, they will only remain relevant if they are updated on a regular basis to include new products and improvements.

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 Renewable Energy Deployment in Colorado by 2030. RUSSELL MUREN (University of California at Berkeley, Berkeley, CA, 94701) CHUCK KUTSCHER (National Renewable Energy Laboratory, Golden, CO, 89401)

Currently most utilities in the state of Colorado are subject to the 20% renewable portfolio standard (RPS) passed by voters in 2004 and expanded by the state legislature in 2007. However, because of bonuses and exemptions written into the law, the true required renewable energy penetration is only 12.3%. This makes this law less then adequate for addressing climate change. This study aims to assess the real renewable energy and carbon impacts of the current RPS and investigates the benefits of increasing the RPS to true 20% and 30% values. To this end a user input-driven predictive Excel model was developed to find the proper technology spread, electrical outputs, and carbon reduction for each RPS. It was found that while all the RPS variants are technically feasible based on available renewable resources, only the 30% RPS meets the carbon reductions that are thought necessary to avoid the worst impacts of climate change. Based on the results of this report the current RPS does not offer an effective avenue to reduce fossil fuel and carbon reduction. Furthermore, if the goal of the current Colorado legislature and administration is carbon reduction, a 30% RPS is the most acceptable avenue.

Analyzing the Response of Frisch-Ring CdZnTe Radiation Detectors. NAJEB ABDUL-JABBAR (University of Michigan, Ann Arbor, MI, 48104) ALEKSEY BOLOTNIKOV (Brookhaven National Laboratory, Upton, NY, 11973)

Cadmium zinc telluride (CdZnTe or CZT) is a direct band gap semiconductor that has very promising qualities as a material for gamma-ray radiation detectors. Unlike the traditional high purity Germanium detectors, which require cryogenic cooling, CZT devices have yielded high detection efficiency and exceptional energy resolution while operating at ambient temperatures. This makes them particularly appealing for national security applications such as explosives detection. It is known that CZT detector performance is dependent on two common factors: CZT crystal defects (mainly Te inclusions present in the crystal structure) and surface irregularities that may cause polarization or electric field defocusing. Using infrared microscopy (with magnification up to x10), Te inclusions on the order of micrometers can be identified. X-ray mapping techniques at Brookhaven’s National Synchrotron Light Source (NSLS) are utilized to analyze CZT surface irregularities at a maximum resolution of 10 µm steps. To determine CZT detector performance, pulse height spectra and correlation curves are obtained using Cs-137 and Ge-68 sources. Results show that CZT crystals with a low concentration of Te inclusions measuring greater than ~10-20 µm in diameter consistently yielded excellent spectral response (the best detector tested had an energy resolution of ~1.1%). Polarization was not observed in any of the samples; however an aberrant defocusing effect was discovered that diminished detector energy resolution by roughly 25%. The research involved in this project is part of a general effort to correlate CZT detector performance with the material properties of CZT.

Application of Modern X-ray Techniques to Common Industrial Materials: Measuring the Local Density of Compressed Cellulose Fibers by Ultra Small Angle X-Ray Scattering. JOSHUA HAMMONS (Texas Tech University, Lubbock, TX, 79414) JAN ILAVSKY (Argonne National Laboratory, Argonne, IL, 60439)

Cellulose Fibers have a wide range of applications from simple typing paper to cleaning and personal hygiene products. In many applications the density of the cellulose fibers is very important to ensure the quality of the product. The dimensions of the lamellae fibers are on the order of 1 micron in thickness and several millimeters long. Several other techniques can be employed such as BET analysis and SEM imaging; however, these techniques are very time consuming for large samples and may require cutting of the sample so that individual sections can be evaluated separately. Ultra small angle scattering (USAXS) allows small angle scattering (SAS) data to be obtained from large volumes of samples up to a few cubic mm. A complete 3-dimensional statistical representation of relatively large volumes of samples can be obtained in approximately 20 to 30 minutes for each sample point. Additionally, as many as 100 different USAXS scans can be performed with little to no interaction required by the experimenter at the Advanced Photon Source Beamline 32-ID. The motivation of this research is to evaluate the ability of USAXS to differentiate between varying levels of cellulose density. SAS data obtained from USAXS experiments span up to 4 decades, in Q, of useful data. Therefore, fiber and void sizes, ranging from 1 nm to just over 1 µm can be evaluated. The correlation between the SAS data and density is due to additional hydrogen bonding between fibers, induced by compression, which result in the reduced shared surface area between the cellulose fibers and voids. The reduced surface area is extracted by the Porod constant, obtained from SAS data. All of the data obtained from 52 USAXS experiments indicate that variation in the SAS data can be directly correlated to the density of the cellulose fibers. Some recommendations for future USAXS experiments were also developed. Small angle scattering data obtained from the sample sheets indicated some multiple scattering affects at low Q. For this reason, future USAXS experiments, on similar samples, should be performed at either energies greater than 18 keV or samples thinner than 2 mm. Additionally, the SAS data can be evaluated at much smaller intervals by decreasing the x-ray beam size. In this manner, a complete map of the fluctuation in density can be made for very large industrial samples, comprised of compressed cellulose fibers.

Applied Material and Energy Evaluation for Biomass Gasification. ISAAC SACHS-QUINTANA (New Mexico Institute of Mining and Technology, Socorro, NM, 87801) CALVIN FEIK (National Renewable Energy Laboratory, Golden, CO, 89401)

As gasoline prices continue to climb, and the price of corn increases, the thermochemical conversion of lignocellulosic biomass into fuels becomes more economical. Economic modeling is the primary tool for assessing the feasibility of biomass conversion processes. Material and energy balances on experimental data are needed to validate the theoretical economic models. Material and energy balances were performed on a pilot scale biomass gasification plant. The plant’s gasifier, thermal cracker, and tar reformer were considered. Usable data was extracted from the pilot plant’s data acquisition system. Differentiation and integration were performed to achieve a basis of calculation. Input and output flows were compared, and material and energy closures were executed. The average material closure for the gasifier, thermal cracker, and tar reformer were 74.34% ± 28.77%, 97.71% ± 3.129%, 100.1% ± 15.05%, respectively. The average energy closures for the thermal cracker and the tar reformer are 107.9% and 101.3% respectively. At the moment, an energy closure for the gasifier cannot be determined because of insufficient data. The experimental data for the tar reformer and thermal cracker can readily be used for validating economic models. The gasifier data cannot. Additional tests in the pilot plant are required to obtain more accurate material and energy streams.

Assessment of a Residential Style Oil-Fired Boiler as a host for a Thermophotovoltaic Combined Heat and Power System. JULIAN CARPENTER (Alfred State College, Alfred, NY, 14802) THOMAS BUTCHER (Brookhaven National Laboratory, Upton, NY, 11973)

Combustion of number 2 heating oil is intrinsically emissive, more so than natural gas, propane or butane. Therefore, oil combustion is a good candidate for power generation using thermophotovoltaic (TPV) cells. In order to test the viability of current residential oil heat technology as a host for TPV combined heat and power generation (CHP), a prototype oil fired TPV CHP system must be built, tested, and characterized. Previous work has shown potential for sufficient power densities using a small 1 cm2 GaSb TPV array with a residential boiler, however, the effects of the much larger array (99 cm2) on achievable power density, and the effects of system geometry, firing rate, combustion conditions and the use of silicon carbide (SiC) emitters is not known. One small and one large (99 cm2) GaSb TPV arrays were tested with various configurations in a modified residential style boiler capable of firing at 0.5 to 0.85 gallon per hour (gph). The use of a reticulated SiC emitter as well as the effect of firing conditions, burner output, and system geometry were varied and measurements of short circuit current (Isc) and open circuit voltage (Voc) were taken to measure power output. It was determined that a large pore SiC foam emitter improved power output, although the pressure drop across the foam plate was problematic. Varying the distance from cell to emitter, the size of the cell, boiler combustion chamber insulation, amount of excess air, and firing rate were found to substantially impact the power output of the TPV cell. Power densities of approximately 1.3 w/cm2 were achieved with the single cell array, and 0.85 W/cm2 with the 99 cell array. Future work should investigate ways to boost power output to over 2 W/cm2, in an effort to provide more than enough power for a stand-alone oil fired boiler TPV CHP system.

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.

Bio-Oil Stability Increase by Minimizing Ash through Pretreatment. DUSTIN BALES (University of Missouri-Rolla, Rolla, MO, 65401) JUSTINUS SATRIO (Ames Laboratory, Ames, IA, 50011)

Comparison of Commercial Office Buildings Using the NC3 Database. KIMBERLY PETTY (Washington State University, Pullman, WA, 99301) EMILY RAUCH (Pacific Northwest National Laboratory, Richland, WA, 99352)

Conceptual Design of a New Large Scale Wind Turbine Drive Train Testing Facility. SCOTT LAMBERT (University of Colorado, Boulder, CO, 80303) JASON COTRELL (National Renewable Energy Laboratory, Golden, CO, 89401)

Laboratory testing of wind turbine drive trains is an important way to validate designs, test reliability, debug systems, and verify computer and analytical models. The large physical size and high torque requirements of modern wind turbines present engineers with unique manufacturing and testing challenges. The 2.5 MW drive train testing facility at the National Renewable Energy Laboratories (NREL) in Colorado is one of a few facilities capable of testing multi-megawatt wind turbine drive trains. The rapid growth of wind turbine size has outpaced the facility’s capacity to test very large wind turbine systems. The goal of the research described in this report is to identify possible configurations, assess the technical challenges, and investigate the costs for a new, larger, 12MW drivetrain test facility. The identification of potential dynamometer configurations was conducted by examining large test facilities in use overseas, and through consultation with industry. Several conceptual designs were modeled using computer aided design software and a preliminary engineering analysis for each concept was conducted. Readily-available components that could be used in this project and suppliers capable of assisting with engineering and manufacturing of limited production components were identified. The concepts where then judged against each other on the basis of cost, component availability, and relative ease of implementation. This research shows that configurations using large custom built gearboxes and motors are expensive and require long lead times due to technical obstacles in engineering and manufacturing. Concepts using large custom components show higher overall system costs than those using multiples of smaller, more readily-available components that distribute the high torque loads over several load paths. While initial estimates show that these distributed-load systems have considerable potential for cost savings, further investigation into these concepts is required to assess the risks involved. Furthermore, the results of this study indicate that concepts such as single motor and gearbox combinations suitable for use in smaller scale test bench systems do not scale well up to 12MW, and do not offer the same setup and configuration flexibility that is possible with distributed load concepts.

Conversion of Geothermal Silica into Value-added Nano-sized Materials. ZHAN HANG YANG (State University of New York at Stony Brook, Stony Brook, NY, 11790) DEVINDER MAHAJAN (Brookhaven National Laboratory, Upton, NY, 11973)

Geothermal brines store natural heat that can be harnessed to produce thermal and electrical power. Unlike fossil fuels, it is a promising, sustainable natural resource with negligible CO₂, SO₂ and NO_x emissions. The circulating hot fluids below the Earth’s surface dissolve minerals and metals like silica, lithium, zinc and manganese from the rocks they travel through. The presence of silica (SiO₂) and other chemicals is a major concern during power production from geothermal brines because it causes scaling and corrosion. The recovery of silica is highly desirable to reduce scaling and to offset the cost of power production. This research project is undertaken to investigate the conversion of silica of high purity into nano-sized, value-added materials such as silicon carbide (SiC) and silicon nitride. Sonication or ultrasound irradiation is employed since this technique is known to produce nanoparticles in-situ. The method involves cavitations, and within the cavities high pressures and high temperatures are generated that can be harnessed to drive chemical reactions. A carbonaceous source, dextrose or graphite, was sonicated with silica to yield silicon carbide. The product was characterized by X-ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR). The XRD patterns of collected solids suggested the presence of three different polytypes of silicon carbide, along with unreacted starting materials. The FTIR measurements showed the appearances of two new peaks at 1015 and 815 cm^- that are probably due to v(Si-O-C) and v(Si-C) stretching, respectively. The vibrations are tentative evidence of silicon carbide formation and possible indicator of the extent of reaction.

Dense Ceramic Membranes for Hydrogen Production. STEPHEN MENKE (University of Illinois at Urbana-Champaign, Urbana, IL, 61801) U. BALACHANDRAN (Argonne National Laboratory, Argonne, IL, 60439)

It is known that the ceramic compound SrFeCo_0.5O_x (SFC2) can be used as an oxygen transport membrane (OTM) to produce hydrogen through water dissociation. The primary challenge for this project was the development of OTMs that transport oxygen at an industrially significant rate. Several factors affect oxygen flux through a membrane including membrane thickness, temperature, and water partial pressure (pH₂O). Previous studies with thick membranes (1.76 ~ 0.21 mm) show that oxygen flux through the membrane increases as membrane thickness decreases. To try and further increase oxygen flux, SFC2 membranes of thickness 20 ~ 30 µm were made. Porous layers made of SFC2 were added on both sides of the membrane to maximize surface reaction kinetics. Membranes were sealed in a reactor assembly to conduct pH₂O dependence measurements as well as compare thickness dependence measurements. A hydrogen production rate of 6.5 cm³/min-cm² was obtained with a thin film membrane at 900°C, 49 vol% H₂O/N₂//80% H₂/He. The hydrogen production rates obtained were similar to previous measurements conducted on a 0.21 mm disk without porous layers. SEM characterization was then performed and indicated differences in the dense layer microstructure when sintered in hydrogen vs. air. Further work should be allotted to better understanding the microstructure of SFC2 as its composition plays an important role in determining the hydrogen production rate.

Design and Implementation of a Sulfur Hexafluoride Gas Transfer System for the Free Electron Laser (FEL) Gun Test Stand. BRIAN TUCKER (Virginia Tech, Blacksburg, VA, 23435) KEVIN JORDAN (Thomas Jefferson National Accelerator Facility, Newport News, VA, 23606)

Jefferson Lab’s Free Electron Laser (FEL) program is currently developing a photocathode test gun to benchmark the performance of new gun technology for eventual use in free electron lasers. The gun uses a 500 kV DC high voltage power supply (HVPS) that connects to a high voltage stack held in a pressure vessel. When the HVPS is being used, the vessel is filled with pressurized sulfur hexafluoride (SF₆), a non-toxic, non-flammable gas that suppresses electrical discharges. Because a full vessel of SF₆ costs approximately $4,000, the gas needs be recycled so that the vessel can be opened without loss of gas. The goal of this project is to develop a system to transfer gas between the pressure vessel and a storage bag without significant loss of gas or contamination. A similar system has been used in the FEL vault for the past eight years. Analyzing the old design revealed ways to improve the gas transfer process. These improvements were used to select the new system’s components. Finally, designs were made to fit the system into the Gun Test Stand vault and to mount the components to the wall. The resulting design improves the old system by implementing a more user friendly layout, automating the entire process, and taking advantage of more advanced pumps and valves. Improving the recycling of SF₆ saves time and money, while helping to ensure smooth gun operation and make HVPS maintenance routine. For now, the new system will serve as an important part of the testing process for the photocathode test gun. Eventually, the changes will be used to upgrade the system in the FEL vault.

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.

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.

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 Vacuum Monte Carlo Code. REYNALDO LOPEZ (University of California, Los Angeles, Los Angeles, CA, 90095) MATTHAEUS LEITNER (Lawrence Berkeley National Laboratory, Berkley, CA, 94720)

This paper presents the initial development of a three-dimensional Monte Carlo computer code that calculates the vacuum pressure of a sample cylindrical pipe vacuum vessel. The implementation of a basic Monte Carlo molecule-tracing algorithm is discussed. The pressure distribution is determined by tracing particles through the vessel structure; converting the trajectory lengths to molecular residency time by using the average molecular velocity. Simulations with various molecule sample sizes are implemented and compared to conventional analytical vacuum formulas. First code results calculate a correct parabolic pressure profile. Future work will include the development of a new geometry module for 3D CAD data, and the implementation of different surface conditions.

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 EnergyPlus Utility to Batch Simulate Building Energy Performance on a National Scale. JAYSON VALENCIA (University of Washington, Seattle, WA, 98195) JAMES DIRKS (Pacific Northwest National Laboratory, Richland, WA, 99352)

Diffractive Optics at Soft X-Ray Wavelengths. TERENCE HOLLOWAY (Norfolk State University, Norfolk, VA, 23504) YANWEI LIU & DAVID ATWOOD (Lawrence Berkeley National Laboratory, Berkley, CA, 94720)

The Center for X-Ray Optics (CXRO) at Lawrence Berkeley National Laboratory works to advance the science and technology of short-wave optical systems through applications using extreme ultraviolet light (EUV) and Soft X-Ray wavelengths that range from 1 nm - 50 nm. The short wavelength radiation is generated by a machine known as a synchrotron. The synchrotron used in our experiment, operated by Lawrence Berkeley National Labs, is the Advance Light Source (ALS). At these wavelengths there are a large number of atomic resonances which cause the absorption of radiation over short distances (in nanometers or micrometers) in most materials. As a result, conventional devices which operate in the optical region of the electromagnetic spectrum are no longer applicable at these short wavelengths. CXRO specializes in two classes of optics that operate at EUV/Soft X-ray wavelengths, reflective multilayer coatings and diffractive optics. This SULI research project places emphasis on nanometer scale diffractive optics. It begins by creating programs for the optical devices using Matlab. A Graphical User Interface (GUI) was created to generate desired patterns for the optics chosen by the user. The GUI runs a simulation of diffractive soft x-ray optics based on electromagnetic wave propagation. The simulation will give us a good idea of how the experiments performed in the ALS will result. After running the simulation, we performed actual synchrotron experiments using those specialized optics at ALS beamline 12.0.2.

Dirty Bomb Simulation Experiment: Usability, Control Condition Selection, and Composite Mission Performance. TIM KLEIN (Oregon State University, Corvallis, OR, 97331) DAVID BRUEMMER (Idaho National Laboratory, Idaho Falls, ID, 83415)

To further the understanding and evaluation of the problems of usability, control condition selection, and composite mission success related to human robot interaction in high stress conditions, a dirty bomb experiment and simulation field study was conducted in an as-near-as-possible real world situation. This paper focuses on the simulation portion of the study with emphasis on the theory that the robot performing under semi autonomous control conditions will show improved holistic performance when compared to manual control conditions. The simulation utilized the current control conditions and interface methods available to the robot system. In the simulation, the participants were asked to find three simulated radioactive sources using the two control conditions, the Shared control using a joystick providing continuous operator control or the newer semi-autonomous Target control. Both control conditions use the robot intelligence kernel (RIK) developed by the Robotic and Human Systems Group at the Idaho National Laboratory for optimized mission success along with environment and robot system safety protection. The data collection came from three different techniques, logged communications from the RIK, participant self evaluation questionnaires, and administrator observations. The greatest differences found during data analysis appear in the participant evaluation characteristics of input and workload demands and the perceptions of control and understanding, shown by comparison and statistical tests of the control conditions. The results show that with an approximate difference of 92-seconds there is no statistically significant difference between the control conditions with respect to the average time taken to complete the task. The results of the holistic composite performance equation, represented by the non control condition specific performance characteristics, favor the Target control condition in which the participants felt less demand and had a higher feeling of mission performance and control. As a design tool, the simulation provides a useful adjunct to field studies and provides insightful evidence, if not entirely conclusive, to continue the development of the Target control condition for use in urban search and rescue, situations involving object detection, and in reducing human exposure during environmentally hazardous missions.

Effect of Chemistry on the Life and Performance of High-Power Lithium-Ion Cells. MAGDALENA FURCZON (University of Illinois at Chicago, Chicago, IL, 60680) DANIEL ABRAHAM (Ames Laboratory, Ames, IA, 50011)

High-power battery technology is key to the commercial success of hybrid electric vehicles (HEVs). These vehicles combine the advantages of the extended driving range and rapid refuelling capability of a conventional vehicle with the increased fuel economy and reduced exhaust gases of an electric vehicle. The relatively high specific-energy and specific-power characteristics of rechargeable lithium-ion batteries make them an attractive alternative to the nickel metal-hydride batteries used in hybrid vehicles currently in the market. The goal of this project is to determine the suitability of various electrode-electrolyte combinations for HEV applications. The cells typically contain a layered oxide-based positive electrode, a graphite-based negative electrode, and an electrolyte containing an organic solvent and lithium-bearing salts (such as LiPF₆). Project activities to date have involved investigation of the effect of alternative salts, such as LiF₂B(C₂O₄) and LiB(C₂O₄)₂,on cell cycling performance. Experiments were conducted on ~2 mAh coin cells and on ~35 mAh cells containing a lithium-tin reference electrode. The cells were electrochemically cycled or subjected to above-ambient temperatures (up to 55 °C). Capacity and impedance measurements were made periodically to determine the deterioration of cell performance with age. Initial data indicate that cells containing the LiF₂B(C₂O₄) salt show better long-term performance than do cells containing the LiPF₆ and LiB(C₂O₄)₂ salts.

Effect of Deposition Temperature on the Crystallinity and Resistivity of ZnO Films by Atomic Layer Deposition using DEZ and H2O. VICTOR OYEYEMI (Goshen College, Goshen, in, 46526) JEFFERY ELAM (Argonne National Laboratory, Argonne, IL, 60439)

ZnO films were deposited by atomic layer deposition using diethyl zinc (DEZ) and ozone as precursors. The depositions were done at temperatures ranging from 50°C to 350°C, and the effect of the different temperatures on growth rate, film morphology, crystallinity and resistivity characterized. It was found that ZnO exhibits linear growth with respect to the number of ALD cycles, and with a rate that increases with increasing deposition temperature; the rate for the 150°C deposition being 0.6Å/cycle. Surface roughening increases with temperature. Scanning electron microscopy shows grain sizes that get bigger with temperature. Also, there is a ZnO (002) preferred crystal orientation. The film resistivity decreases with growth temperature for temperatures less than 300°C but increase sharply for higher temperatures. The minimum resistivity of 0.04O was recorded for the 250°C film. Measurement of carrier mobility of the films shows a near inverse relationship with resistivity.

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.

Effective Queue Distributions in Video Streaming: A User Perspective. R BENJAMIN CLAY (Virginia Tech, Blacksburg, VA, 24060) SAMI AYYORGUN (Los Alamos National Laboratory, Los Alamos, NM, 87545)

Queuing theory and buffer control are areas of great interest as networks become large and unmanageable. Specifically, guaranteeing a quality of service (QoS) in a large, uncontrolled network such as the internet is important from both a business perspective (selling a service at a specified QoS) and a users perspective. In order to ensure that data reaches the intended target at the intended rate, stochastic rate control algorithms can be used to guarantee a service within a given probability. To this end, previous work has determined and elaborated upon mathematical methods to achieve optimum buffer control given a generic packet-based data source. Our work extends these algorithms to streaming video, using subjective analysis to determine the appropriate equations and values to make the rate control transparent to the end user. To do so, a server-client implementation has been built on top of the popular opensource video player VLC. The rate control algorithms specified in previous work are built as the core of the server application, modifying VLC’s UDP streaming server component. The client is another copy of VLC, operating as a UDP streaming client. Preliminary results indicate correlation between decay rate and video quality for those distributions that employ a decay rate.

Effects of Humidity in Inlet Air on a Proton Exchange Membrane (PEM) Fuel Cell. ANDREW FASANO (Farmingdale State College, Farmingdale, NY, 11735) DEVINDER MAHAJON (Brookhaven National Laboratory, Upton, NY, 11973)

Air humidification plays a crucial role in the performance of Polymer Electrolyte Membrane (PEM) fuel cells. The present study aims to determine the effect of relative humidity on the cathode side that will produce optimal fuel cell performance at various power levels. Usually, increasing air humidity improves fuel cell performance until it reaches an optimal operating condition. If humidity continues to increase beyond this point, the fuel cell experiences flooding due to the isolation of the catalyst surface from the reactant gases which causes considerable power degradation of the fuel cell. The recorded data shows that air humidification at relatively low temperature levels tends to hinder the cell performance due to its saturation with water. When current levels are increased, an increase in inlet air humidity causes the cell to initially drop in performance due to a certain degree of catalyst flooding at low temperature. However, as the cell begins to increase in temperature, the humidification of inlet air results in a slight recovery of power in the cell output. In conclusion, at room and low temperatures humidification of the inlet air to the PEM fuel cell exhibits a negative effect on the cell power output due to partial flooding. But as the fuel cell continued to operate, the temperature increased that allowed the initial flooding to subside and power escalation was observed.

Electrical Systems Analysis of Off-Site Groundwater Treatment Facilities to Determine Arc Flash Hazard. JOHN BOUCHER (Middlebury College, Middlebury, Vermont, 5753) ALAN RAPHAEL (Brookhaven National Laboratory, Upton, NY, 11973)

Before an arc flash accident prompted Brookhaven National Laboratory (BNL) to devise the Arc Flash Analysis Project, a project designed to achieve a complete electrical systems analysis of all BNL systems and buildings, many of BNL’s older facilities had not been inspected to determine if they satisfied the National Fire Protection Association’s "Standard for Electrical Safety in the Workplace" (NFPA 70E - 2004). The following study examined the electrical systems of BNL’s Off-Site Water Treatment Facilities for their compliance with NFPA 70E - 2004 and so was only a piece of the comprehensive Arc Flash Analysis Project. Electrical information such as equipment layout, manufacturing, and operating information for all electrical components such as panels, fuses, and circuit breakers, as well as cable sizes, types, and approximate lengths was obtained by manually inspecting and tracing out the water treatment facilities’ electrical systems. Using SKM PTW Power Tools Software (PTW), this information was organized, illustrated, and then analyzed to establish the electrical systems’ susceptibility to and energy available for arc flash. The work done for this study produced single-line electrical diagrams via PTW containing all electrical equipment down through the lowest rated panels (480 Volt or 208 Volt) to any 3 phase 480 Volt or 3 phase 208 Volt / 225 Amp or greater equipment for the facilities. With the supplied information in the single-line diagrams, PTW was used to compute information such as arc flash incident energy level at each equipment location, the flash protection boundary, and the recommended Personal Protective Equipment (PPE) at these locations. This study sought to achieve greater safety for those working on the concerned electrical systems by providing recommendations for necessary PPE for electrical workers, collecting data to be archived, managed, updated as necessary, and made accessible to facility engineers for future electrical work, and affixing up-to-date arc flash warning labels to all appropriate electrical equipment.

Electricity Market Complex Adaptive System (EMCAS) as a tool for teaching undergraduates about power market, environmental policies and renewable energy. ANGEL REYES (University of Puerto Rico, Mayaguez, PR, 680) EDUARDO I. ORTIZ-RIVERA and LUIS RODRIGUEZ (Argonne National Laboratory, Argonne, IL, 60439)

Electricity Market Complex Adaptive Systems (EMCAS) is the next generation energy and environmental market simulation tool developed recently by Argonne National Laboratories. EMCAS simulates the behavior of restructured power market participants using an agent-based complex adaptive systems approach. EMCAS provides an agent based framework to capture and investigate the complex interactions between the physical infrastructures and the economic behavior of market participants that are a trademark of the newly emerging markets. As an introduction for the EMCAS software simple cases were studied in order to understand the capabilities of this analytical tool. The eleven node and the central European cases were hypothetical cases in which the main functions of EMCAS were studied. After that, the simple market of Puerto Rico`s grid was studied using EMCAS to analyze how the system behaves. Also, the effect of the Hurricane George and the Palo Seco’s power plant fire on the system of the Puerto Rico Electric Power Authority was analyzed. Future studies will include the analysis and the development of the system in the next couple of years, the effect of adding new transmission lines in the transmission system and the addition of renewable energy sources in the island’s power system.

Electrolysis and Pressure Driven Flow for Temperature Gradient Focusing. ELLIS GARAI (University of California, Los Angeles, Los Angeles, CA, 90095) KEVIN NESS (Lawrence Livermore National Laboratory, Livermore, CA, 94550)

Bio-warfare detection systems are a necessary means of maintaining national security. In order for a detection system to be practical and largely deployed it should be easy to use, affordable, portable, low power, rapid, accurate, and autonomous. Currently, bio-warfare detection instrumentation do not meet the aforementioned specifications due to the lack of automated front-end sample preparation(FESP). FESP consists of purifying, concentrating, and separating ‘complex’ environmental samples in order to improve the downstream detection assays performance. Temperature gradient focusing(TGF) has been identified as a novel microfluidic technique to aid in the necessary autonomous FESP. TGF is the balance of an advective flux and an electrophoretic flux, in the presence of a temperature gradient, to ensure focusing only occurs at a unique spatial location along the axis of the microchannel. The main factors influencing the stability during TGF are a stable flow field and a stable electric field within the microfluidic system; therefore, these parameters must be tightly controlled. Electrolysis greatly influences these parameters; any gas formation within a channel can perturb both the flow and at the very least perturb the electric field. An in-line gas management system was devised to overcome this obstacle. Several approaches were taken to address this issue. The first was to remove the gas forming at the electrode through a porous gas permeable Teflon material while under vacuum. The second consisted of a large sealed air/liquid electrode reservoir, through which bubbles would float to the surface. With certain disadvantages in the first two, a final, more promising approach to directly isolate the gas formation was chosen. By using a proton permissible material (Nafion), gas generated at the electrode is isolated from the TGF flow line and swept down a separate line using a constant running buffer. In addition to electrolysis altering the flow field, generating a stable flow at the ~100 nL/min range was another hurdle. Commercial pumping technology has an ~10% variation in the flow rate at any given time. By using a high resolution flow sensor and a dynamically controlled pressure source, in combination with a custom PID control scheme, a stable flow rate of less than 1% change (~ 1 nL/min) was attained. Through this tighter control over important TGF parameters improvements in purification, separation, and concentration effects are realized.

Electromagnetic Interference from the ILC Beams. LAVONDA BROWN (Norfolk State University, Norfolk, VA, 23504) GARY BOWER (Stanford Linear Accelerator Center, Stanford, CA, 94025)

Electromagnetic interference is an emerging problem of the future. This investigation analyzed the data collected from airborne radiation waves that caused electronic devices to fail. This investigation was set up at SLAC in End Station A and the data collected from the electromagnetic waves were received from antennas. In order to calibrate the antennas it required a signal generator to transmit the signals to the antenna and a digital oscilloscope to receive the radiation waves from the other antenna. The signal generator that was used was only able to generate signals between 1 and 1.45 GHz; therefore, the calibrations were not able to be completed. Instead, excel was used to create a curve fitting for the attenuation factors that were already factory calibrated. The function from the curve fitting was then used to extend the calibrations on the biconical and yagi antennas. A fast Fourier Transform was then ran in Matlab on the radiation waves received by the oscilloscope; in addition, the attenuation factors were calculated into the program to show the actual amplitudes of these radiation waves. For future research, the antennas will be manually calibrated and the results will be reanalyzed.

Ensuring Co-planarity of Tiled Optical Surfaces. MICHAEL DAWSON-HAGGERTY (Tufts University, Medford, MA, 2155) PAUL O'CONNOR (Brookhaven National Laboratory, Upton, NY, 11973)

The Large Synoptic Survey Telescope (LSST) is designed to have an extremely large field of view, 9.62 square degrees, nearly 50 times the area of the full moon. The digital camera used to record the images provided by such a large field needs to be enormous. The focal plane of the camera is a circular area 60 cm in diameter, covered in a tiled surface of 4cm square CCD imaging chips, which provide the digital image for analysis. Although the area is large, the tiled sensors need to be coplanar to within plus or minus five microns, as the light is converging on a very specific, precise point. To do this, the tiles are grouped into 3x3 arrays called 'rafts' which can be constructed individually. The rafts are scanned with a laser confocal displacement meter mounted onto an x-y gantry system. The displacement meter is scanned over the raft surface, and a 3D model can be made of the raft. Tilt and vertical displacement of each CCD can be assessed, and extremely thin foil shims of known thickness can be inserted to compensate. The scan is repeated until all silicon sensor surfaces are within tolerances. This allows the effectiveness of thin- foil spacers to be assessed, as well as the overall feasibility of the precision requirements for the tiled surface, a greater precision then has been attempted previously. This work is a small portion of a much larger project being researched to develop the LSST optical and mechanical systems, and once completed will play a large part in ensuring a clear and focused image.

Evaluating the efficacy of mustard (Sinapis alba) seed meal as an organic control method for invasive Harding grass. GREGORY RYBKA (The Pennsylvania State University, University Park, PA, 16802) ROBERT VAN BUSKIRK (Lawrence Berkeley National Laboratory, Berkley, CA, 94720)

Biodiesel is widely viewed as an alternative to fossil-based fuels. The production of oil for biodiesel by pressing mustard seed has been studied and found to be feasible though the process has shown to be uneconomical. White mustard meal (Sinapis alba) contains glucosinolates (GLS) which when hydrolyzed break down into toxins to various plants, such as ionic isothyocianate and thyociante. The research reported in this study considers using the remaining mustard seed meal as an organic bioherbicide to control Harding grass, an invasive plant in California. A randomized complete block experimental design was employed in field trials, involving four treatments of mustard meal applied at varying rates of 0.5 t/acre, 1 t/acre, 4 t/acre and 0 t/acre (the control). The treatments were applied to two plots each with 16 subplots, where one plot had above ground (AG) biomass removed prior to application and on the other no removal took place. The subplots were initially characterized by the quantity of Harding grass per unit area, at 20%, 40%, 60% and 80% coverage. On all subplots water was applied exclusively by rainfall and totaled 1.5 inches. After six weeks, the Harding grass was removed and weighed; the water content of the removed grass was measured in order to determine the AG biomass for each subplot. The average AG biomass of all treated plots and that at each application rate were larger than that for their respective control subplots, though using an analysis of variance the data sets were not found to be statistically different. The initial and final measurements of Harding grass were also found to have discrepancies as they were negatively correlated for the control plots, indicating an issue with the use of both area and mass measurements. Due to the lack of statistically significant evidence it is not possible to draw conclusions on the potential of mustard meal as economically supporting mustard seed as a source for alternative fuel.

Evaluation and Recommendation of Advanced Laser Power and Laser Energy Meters for Potential Acquisition. TIMOTHY CHEERS (Southwest Tennessee Community College, Memphis, TN, 38134) MARK LUDWIG (Lawrence Livermore National Laboratory, Livermore, CA, 94550)

Lasers are powerful research tools but pose significant safety issues if not monitored and controlled appropriately. The ever evolving world of technology has developed smaller, more advanced meters used to monitor power-energy emissions from lasers. These devices are called laser power and laser energy meters. The Hazards Control Department (HCD) uses power and energy meters to verify output of lasers, reclassify lasers as needed, and conduct accident investigations should one occur. Due to their safety applications, the HCD power-energy meters are calibrated to National Institute of Science and Technology standards and are an integral component of Lawrence Livermore Nationa

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