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2008 Summer Research Institute Interfacial and Condensed Phase Chemical Physics Annual Report (open access)

2008 Summer Research Institute Interfacial and Condensed Phase Chemical Physics Annual Report

For the fifth year, the Pacific Northwest National Laboratory in Richland, Washington, invited graduate students, postdoctoral fellows, university faculty, and students entering graduate students from around the world to participate in the Summer Research Institute in Interfacial and Condensed Phase Chemical Physics. The institute offers participants the opportunity to gain hands-on experience in top-notch research laboratories while working along internationally respected mentors. Of the 38 applicants, 20 were accepted for the 8- to 10-week program. The participants came from universities as close as Seattle and Portland and as far away as Germany and Singapore. At Pacific Northwest National Laboratory, the 20 participants were mentored by 13 scientists. These mentors help tailor the participant’s experience to the needs of that person. Further, the mentors provide guidance on experimental and theoretical techniques, research design and completion, and other aspects of scientific careers in interfacial and condensed phase chemical physics. The research conducted at the institute can result in tangible benefits for the participants. For example, many have co-authored papers that have been published in peer-reviewed journals, including top-rated journals such as Science. Also, they have presented their research at conferences, such as the Gordon Research Conference on Dynamics at Surfaces and the …
Date: November 1, 2008
Creator: Garrett, Bruce C.; Tonkyn, Russell G. & Avery, Nachael B.
Object Type: Report
System: The UNT Digital Library
Accelerated Stress Testing and Diagnostic Analysis of Degradation in CdTe Solar Cells (open access)

Accelerated Stress Testing and Diagnostic Analysis of Degradation in CdTe Solar Cells

The primary goal of this study was to ascertain the presence and types of mechanisms affecting CdS/CdTe device stability in the temperature range of 60 to 120 ..deg..C. It should be noted that the results presented were specific to cells made using the specific growth conditions described.
Date: November 1, 2008
Creator: Albin, D. S.
Object Type: Article
System: The UNT Digital Library
Advanced Power Electronic Interfaces for Distributed Energy Systems, Part 2: Modeling, Development, and Experimental Evaluation of Advanced Control Functions for Single-Phase Utility-Connected Inverter (open access)

Advanced Power Electronic Interfaces for Distributed Energy Systems, Part 2: Modeling, Development, and Experimental Evaluation of Advanced Control Functions for Single-Phase Utility-Connected Inverter

Integrating renewable energy and distributed generations into the Smart Grid architecture requires power electronic (PE) for energy conversion. The key to reaching successful Smart Grid implementation is to develop interoperable, intelligent, and advanced PE technology that improves and accelerates the use of distributed energy resource systems. This report describes the simulation, design, and testing of a single-phase DC-to-AC inverter developed to operate in both islanded and utility-connected mode. It provides results on both the simulations and the experiments conducted, demonstrating the ability of the inverter to provide advanced control functions such as power flow and VAR/voltage regulation. This report also analyzes two different techniques used for digital signal processor (DSP) code generation. Initially, the DSP code was written in C programming language using Texas Instrument's Code Composer Studio. In a later stage of the research, the Simulink DSP toolbox was used to self-generate code for the DSP. The successful tests using Simulink self-generated DSP codes show promise for fast prototyping of PE controls.
Date: November 1, 2008
Creator: Chakraborty, S.; Kroposki, B. & Kramer, W.
Object Type: Report
System: The UNT Digital Library
AFC-1 Fuel Rodlet Fission Power Deposition Validation in ATR (open access)

AFC-1 Fuel Rodlet Fission Power Deposition Validation in ATR

One of the viable options of long-term geological disposal of the nuclear power reactors generated spent fuel is to extract plutonium, the minor actinides (MA) and potentially long-lived fission products from the spent fuel and transmute them into short-lived or stable radionuclides in an appropriate reactor for the reduction of the radiological toxicity of the nuclear waste stream. An important component of that technology will be a non-fertile / low-fertile actinide transmutation fuel form containing the plutonium, neptunium, americium (and possibly curium) isotopes to be transmuted. Such advanced fuel forms, especially ones enriched in the long-life minor actinide (LLMA) elements (i.e., Np, Am, Cm), have minimal irradiation performance data available from which to establish a transmutation fuel form design. Recognizing these needs, an Advanced Fuel Cycle test series-1 (AFC-1) irradiation test on a variety of candidate fuel forms is now being conducted in Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL). The first advanced fuel experiment (AFC-1) has been finalized and the test assembly analyzed for insertion and irradiation in ATR. The ATR core consists of a serpentine and rotationally symmetric fuel assembly about the z-axis of the core center. The plan view of the ATR core configuration …
Date: November 1, 2008
Creator: Chang, G. S.; Lillo, M. A. & Utterbeck, D. J.
Object Type: Article
System: The UNT Digital Library
Analysis on the Density Driven Air-Ingress Accident in VHTRs (open access)

Analysis on the Density Driven Air-Ingress Accident in VHTRs

Air-ingress following the pipe rupture is considered to be the most serious accident in the VHTRs due to its potential problems such as core heat-up, structural integrity and toxic gas release. Previously, it has been believed that the main air-ingress mechanism of this accident is the molecular diffusion process between the reactor core and the cavity. However, according to some recent studies, there is another fast air-ingress process that has not been considered before. It is called density-driven stratified flow. The potential for density-driven stratified air ingress into the VHTR following a large-break LOCA was first described in the NGNP Methods Technical Program based on stratified flow studies performed with liquid. Studies on densitygradient driven stratified flow in advanced reactor systems has been the subject of active research for well over a decade since density-gradient dominated stratified flow is an inherent characteristic of passive systems used in advanced reactors. Recently, Oh et al. performed a CFD analysis on the stratified flow in the VHTR, and showed that this effect can significantly accelerate the air-ingress process in the VHTRs. They also proposed to replace the original air-ingress scenario based on the molecular diffusion with the one based on the stratified flow. …
Date: November 1, 2008
Creator: Kim, Eung Soo; Oh, Chang; Schultz, Richard & Petti, David
Object Type: Article
System: The UNT Digital Library
The Arctic as a test case for an assessment of climate impacts on national security. (open access)

The Arctic as a test case for an assessment of climate impacts on national security.

The Arctic region is rapidly changing in a way that will affect the rest of the world. Parts of Alaska, western Canada, and Siberia are currently warming at twice the global rate. This warming trend is accelerating permafrost deterioration, coastal erosion, snow and ice loss, and other changes that are a direct consequence of climate change. Climatologists have long understood that changes in the Arctic would be faster and more intense than elsewhere on the planet, but the degree and speed of the changes were underestimated compared to recent observations. Policy makers have not yet had time to examine the latest evidence or appreciate the nature of the consequences. Thus, the abruptness and severity of an unfolding Arctic climate crisis has not been incorporated into long-range planning. The purpose of this report is to briefly review the physical basis for global climate change and Arctic amplification, summarize the ongoing observations, discuss the potential consequences, explain the need for an objective risk assessment, develop scenarios for future change, review existing modeling capabilities and the need for better regional models, and finally to make recommendations for Sandia's future role in preparing our leaders to deal with impacts of Arctic climate change on …
Date: November 1, 2008
Creator: Taylor, Mark A.; Zak, Bernard Daniel; Backus, George A.; Ivey, Mark D. & Boslough, Mark Bruce Elrick
Object Type: Report
System: The UNT Digital Library
Auto-DR and Pre-cooling of Buildings at Tri-City Corporate Center (open access)

Auto-DR and Pre-cooling of Buildings at Tri-City Corporate Center

Over the several past years, Lawrence Berkeley National Laboratory (LBNL) has conducted field tests for different pre-cooling strategies in different commercial buildings within California. The test results indicated that pre-cooling strategies were effective in reducing electric demand in these buildings during peak periods. This project studied how to optimize pre-cooling strategies for eleven buildings in the Tri-City Corporate Center, San Bernardino, California with the assistance of a building energy simulation tool -- the Demand Response Quick Assessment Tool (DRQAT) developed by LBNL's Demand Response Research Center funded by the California Energy Commission's Public Interest Energy Research (PIER) Program. From the simulation results of these eleven buildings, optimal pre-cooling and temperature reset strategies were developed. The study shows that after refining and calibrating initial models with measured data, the accuracy of the models can be greatly improved and the models can be used to predict load reductions for automated demand response (Auto-DR) events. This study summarizes the optimization experience of the procedure to develop and calibrate building models in DRQAT. In order to confirm the actual effect of demand response strategies, the simulation results were compared to the field test data. The results indicated that the optimal demand response strategies worked …
Date: November 1, 2008
Creator: Yin, Rongxin; Xu, Peng & Kiliccote, Sila
Object Type: Report
System: The UNT Digital Library
The Bastrop Advertiser (Bastrop, Tex.), Vol. 155, No. 72, Ed. 1 Saturday, November 1, 2008 (open access)

The Bastrop Advertiser (Bastrop, Tex.), Vol. 155, No. 72, Ed. 1 Saturday, November 1, 2008

Semi-weekly newspaper from Bastrop, Texas that includes local, state and national news along with advertising.
Date: November 1, 2008
Creator: Wright, Cyndi
Object Type: Newspaper
System: The Portal to Texas History
The Baytown Sun (Baytown, Tex.), Vol. 88, No. 304, Ed. 1 Saturday, November 1, 2008 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 88, No. 304, Ed. 1 Saturday, November 1, 2008

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: November 1, 2008
Creator: Clements, Clifford E.
Object Type: Newspaper
System: The Portal to Texas History
Beam dynamics studies of the 8 GeV Linac at FNAL (open access)

Beam dynamics studies of the 8 GeV Linac at FNAL

The proposed 8-GeV proton driver (PD) linac at FNAL includes a front end up to {approx}420 MeV operating at 325 MHz and a high energy section at 1300 MHz. A normal conducting RFQ and short CH type resonators are being developed for the initial acceleration of the H-minus or proton beam up to 10 MeV. From 10 MeV to {approx}420 MeV, the voltage gain is provided by superconducting (SC) spoke-loaded cavities. In the high-energy section, the acceleration will be provided by the International Linear Collider (ILC)-style SC elliptical cell cavities. To employ existing, readily available klystrons, an RF power fan out from high-power klystrons to multiple cavities is being developed. The beam dynamics simulation code TRACK, available in both serial and parallel versions, has been updated to include all known H-minus stripping mechanisms to predict the exact location of beam losses. An iterative simulation procedure is being developed to interact with a transient beam loading model taking into account RF feedback and feedforward systems.
Date: November 1, 2008
Creator: Ostroumov, P.N.; Mustapha, B.; /Argonne; Carneiro, J.-P. & /Fermilab
Object Type: Article
System: The UNT Digital Library
Beam physics of the 8-GeV H-minus linac (open access)

Beam physics of the 8-GeV H-minus linac

Fermilab is developing the concept and design of an 8-GeV superconducting H-minus linac with the primary mission of increasing the intensity of the Main Injector for the production of neutrino superbeams. The front-end of the linac up to 420 MeV operates at 325 MHz and accelerates beam from the ion source using a room temperature radio-frequency quadrupole followed by short CH type resonators and superconducting spoke resonators. In the high energy section, the acceleration is provided by the International Linear Collider (ILC)-style superconducting elliptical 1.3 GHz cavities. The beam physics for the linac is presented in this paper using two beam dynamics codes: TRACK and ASTRA.
Date: November 1, 2008
Creator: Carneiro, J.-P.; /Fermilab; Mustapha, B.; Ostroumov, P.N. & /Argonne
Object Type: Article
System: The UNT Digital Library
Beyond the Standard Model Physics Searches at the Tevatron (open access)

Beyond the Standard Model Physics Searches at the Tevatron

The recent results on a number of searches performed at Tevatron for new phenomena beyond Standard Model are presented. The topics include the experimental tests of SUSY with mSUGRA and GMSB breaking scenarios. The latest analyses on large extra dimensions, new massive bosons are covered as well. The results are based on experimental data samples collected at the Tevatron with CDF and DO detectors and comprising a total integrated luminosity up to {approx} 2.7 fb{sup -1}.
Date: November 1, 2008
Creator: Gorelov, Igor V.
Object Type: Article
System: The UNT Digital Library
Building America System Research Plan for Reduction of Miscellaneous Electrical Loads in Zero Energy Homes (open access)

Building America System Research Plan for Reduction of Miscellaneous Electrical Loads in Zero Energy Homes

This research plan describes the overall scope of system research that is needed to reduce miscellaneous electrical loads (MEL) in future net zero energy homes.
Date: November 1, 2008
Creator: Barley, C. D.; Haley, C.; Anderson, R. & Pratsch, L.
Object Type: Report
System: The UNT Digital Library
Calorimeter Simulation with Hadrons in CMS (open access)

Calorimeter Simulation with Hadrons in CMS

CMS is using Geant4 to simulate the detector setup for the forthcoming data from the LHC. Validation of physics processes inside Geant4 is a major concern in view of getting a proper description of jets and missing energy for signal and background events. This is done by carrying out an extensive studies with test beam using the prototypes or real detector modules of the CMS calorimeter. These data are matched with Geant4 predictions using the same framework that is used for the entire CMS detector. Tuning of the Geant4 models is carried out and steps to be used in reproducing detector signals are defined in view of measurements of energy response, energy resolution, transverse and longitudinal shower profiles for a variety of hadron beams over a broad energy spectrum between 2 to 300 GeV/c. The tuned Monte Carlo predictions match many of these measurements within systematic uncertainties.
Date: November 1, 2008
Creator: Piperov, Stefan & /Sofiya, Inst. Nucl. Res. /Fermilab
Object Type: Article
System: The UNT Digital Library
CAPTAN: A hardware architecture for integrated data acquisition, control, and analysis for detector development (open access)

CAPTAN: A hardware architecture for integrated data acquisition, control, and analysis for detector development

The Electronic Systems Engineering Department of the Computing Division at the Fermi National Accelerator Laboratory has developed a data acquisition system flexible and powerful enough to meet the needs of a variety of high energy physics applications. The system described in this paper is called CAPTAN (Compact And Programmable daTa Acquisition Node) and its architecture and capabilities are presented in detail here. The three most important characteristics of this system are flexibility, versatility and scalability. These three main features are supported by key architectural features; a vertical bus that permits the user to stack multiple boards, a gigabit Ethernet link that permits high speed communications to the system and the core group of boards that provide specific capabilities for the system. In this paper, we describe the system architecture, give an overview of its capabilities and point out possible applications.
Date: November 1, 2008
Creator: Turqueti, Marcos; Rivera, Ryan A.; Prosser, Alan; Andresen, Jeffry; Chramowicz, John & /Fermilab
Object Type: Article
System: The UNT Digital Library
Case studies of the application of the Certification Framework to two geologic carbon sequestration sites (open access)

Case studies of the application of the Certification Framework to two geologic carbon sequestration sites

We have developed a certification framework (CF) for certifying that the risks of geologic carbon sequestration (GCS) sites are below agreed-upon thresholds. The CF is based on effective trapping of CO2, the proposed concept that takes into account both the probability and impact of CO2 leakage. The CF uses probability estimates of the intersection of conductive faults and wells with the CO2 plume along with modeled fluxes or concentrations of CO2 as proxies for impacts to compartments (such as potable groundwater) to calculate CO2 leakage risk. In order to test and refine the approach, we applied the CF to (1) a hypothetical large-scale GCS project in the Texas Gulf Coast, and (2) WESTCARB's Phase III GCS pilot in the southern San Joaquin Valley, California.
Date: November 1, 2008
Creator: Oldenburg, Curtis M.; Nicot, J.-P. & Bryant, S.L.
Object Type: Article
System: The UNT Digital Library
Characterizing fault-plume intersection probability for geologic carbon sequestration risk assessment (open access)

Characterizing fault-plume intersection probability for geologic carbon sequestration risk assessment

Leakage of CO{sub 2} out of the designated storage region via faults is a widely recognized concern for geologic carbon sequestration. The probability of such leakage can be separated into the probability of a plume encountering a fault and the probability of flow along such a fault. In the absence of deterministic fault location information, the first probability can be calculated from regional fault population statistics and modeling of the plume shape and size. In this study, fault statistical parameters were measured or estimated for WESTCARB's Phase III pilot test injection in the San Joaquin Valley, California. Combining CO{sub 2} plume model predictions with estimated fault characteristics resulted in a 3% probability that the CO{sub 2} plume will encounter a fault fully offsetting the 180 m (590 ft) thick seal. The probability of leakage is lower, likely much lower, as faults with this offset are probably low-permeability features in this area.
Date: November 1, 2008
Creator: Jordan, Preston D.; Oldenburg, Curtis M. & Nicot, Jean-Philippe
Object Type: Article
System: The UNT Digital Library
Clean Cities 2009 Vehicle Buyer's Guide (Brochure) (open access)

Clean Cities 2009 Vehicle Buyer's Guide (Brochure)

Document features photos and specs on the model year 2009 alternative fuel vehicles.
Date: November 1, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Closure Report for Corrective Action Unit 481: Area 12 T-Tunnel Conditional Release Storage Yard, Nevada Test Site, Nevada (open access)

Closure Report for Corrective Action Unit 481: Area 12 T-Tunnel Conditional Release Storage Yard, Nevada Test Site, Nevada

Corrective Action Unit (CAU) 481 is identified in the Federal Facility Agreement and Consent Order (FFACO) as Area 12 T-Tunnel Conditional Release Storage Yard. CAU 481 is located in Area 12 of the Nevada Test Site, which is approximately 65 miles northwest of Las Vegas, Nevada. This CAU consists of one Corrective Action Site (CAS), CAS 12-42-05, Housekeeping Waste. CAU 481 closure activities were conducted by the Defense Threat Reduction Agency from August 2007 through July 2008 according to the FFACO and Revision 3 of the Sectored Clean-up Work Plan for Housekeeping Category Waste Sites. Closure activities included removal and disposal of construction debris and low-level waste. Drained fluids, steel, and lead was recycled as appropriate. Waste generated during closure activities was appropriately managed and disposed.
Date: November 1, 2008
Creator: National Security Technologies, LLC
Object Type: Report
System: The UNT Digital Library
Combined Waste Form Cost Trade Study (open access)

Combined Waste Form Cost Trade Study

A new generation of aqueous nuclear fuel reprocessing, now in development under the auspices of the DOE Office of Nuclear Energy (NE), separates fuel into several fractions, thereby partitioning the wastes into groups of common chemistry. This technology advance enables development of waste management strategies that were not conceivable with simple PUREX reprocessing. Conventional wisdom suggests minimizing high level waste (HLW) volume is desirable, but logical extrapolation of this concept suggests that at some point the cost of reducing volume further will reach a point of diminishing return and may cease to be cost-effective. This report summarizes an evaluation considering three groupings of wastes in terms of cost-benefit for the reprocessing system. Internationally, the typical waste form for HLW from the PUREX process is borosilicate glass containing waste elements as oxides. Unfortunately several fission products (primarily Mo and the noble metals Ru, Rh, Pd) have limited solubility in glass, yielding relatively low waste loading, producing more glass, and greater disposal costs. Advanced separations allow matching the waste form to waste stream chemistry, allowing the disposal system to achieve more optimum waste loading with improved performance. Metals can be segregated from oxides and each can be stabilized in forms to minimize …
Date: November 1, 2008
Creator: Gombert, Dirk; Piet, Steve; Trickel, Timothy; Carter, Joe; Vienna, John; Ebert, Bill et al.
Object Type: Report
System: The UNT Digital Library
Computational and experimental study of nanoporous membranes for water desalination and decontamination. (open access)

Computational and experimental study of nanoporous membranes for water desalination and decontamination.

Fundamentals of ion transport in nanopores were studied through a joint experimental and computational effort. The study evaluated both nanoporous polymer membranes and track-etched nanoporous polycarbonate membranes. The track-etched membranes provide a geometrically well characterized platform, while the polymer membranes are more closely related to ion exchange systems currently deployed in RO and ED applications. The experimental effort explored transport properties of the different membrane materials. Poly(aniline) membranes showed that flux could be controlled by templating with molecules of defined size. Track-etched polycarbonate membranes were modified using oxygen plasma treatments, UV-ozone exposure, and UV-ozone with thermal grafting, providing an avenue to functionalized membranes, increased wettability, and improved surface characteristic lifetimes. The modeling effort resulted in a novel multiphysics multiscale simulation model for field-driven transport in nanopores. This model was applied to a parametric study of the effects of pore charge and field strength on ion transport and charge exclusion in a nanopore representative of a track-etched polycarbonate membrane. The goal of this research was to uncover the factors that control the flux of ions through a nanoporous material and to develop tools and capabilities for further studies. Continuation studies will build toward more specific applications, such as polymers with attached …
Date: November 1, 2008
Creator: Hickner, Michael A. (Penn State University, University Park, PA); Chinn, Douglas Alan (Sandia National Laboratories, Albuquerque, NM); Adalsteinsson, Helgi; Long, Kevin R. (Texas Tech University, Lubbock, TX); Kent, Michael Stuart (Sandia National Laboratories, Albuquerque, NM); Debusschere, Bert J. et al.
Object Type: Report
System: The UNT Digital Library
Crystal Growth and Wafer Processing for High Yield and High Efficiency Solar Cells: Final Report, 1 October 2003 - 15 January 2008 (open access)

Crystal Growth and Wafer Processing for High Yield and High Efficiency Solar Cells: Final Report, 1 October 2003 - 15 January 2008

Hardness, elastic modulus, and fracture toughness of low and high carrier-lietime regions in polycrystalline silicon were evaluated using the nanoindentation technique.
Date: November 1, 2008
Creator: Rozgonyi, G. A. & Youssef, K.
Object Type: Report
System: The UNT Digital Library
Design of a compact heat exchanger for heat recuperation from a high temperature electrolysis system (open access)

Design of a compact heat exchanger for heat recuperation from a high temperature electrolysis system

Design details of a compact heat exchanger and supporting hardware for heat recuperation in a high-temperature electrolysis application are presented. The recuperative heat exchanger uses a vacuum-brazed plate-fin design and operates between 300 and 800°C. It includes corrugated inserts for enhancement of heat transfer coefficients and extended heat transfer surface area. Two recuperative heat exchangers are required per each four-stack electrolysis module. The heat exchangers are mated to a base manifold unit that distributes the inlet and outlet flows to and from the four electrolysis stacks. Results of heat exchanger design calculations and assembly details are also presented.
Date: November 1, 2008
Creator: Housley, G. K.; O'Brien, J. E. & Hawkes, G. L.
Object Type: Article
System: The UNT Digital Library
The Differential cross section distribution of Drell-Yan dielectron pairs in the z boson mass region (open access)

The Differential cross section distribution of Drell-Yan dielectron pairs in the z boson mass region

We report on a measurement of the rapidity distribution, d{sigma}/dy, for Z=Drell-Yan {yields} ee events produced in p{bar p} collisions at {radical}s = 1.96 TeV. The data sample consists of 2.13 fb{sup -1} corresponding to about 160,000 Z/Drell-Yan {yields} ee candidates in the Z boson mass region collected by the Collider Detector at Fermilab. The d{sigma}/dy distribution, which is measured over the full kinematic range for e{sup +}e{sup -} pairs in the invariant mass range 66 < M{sub ee} < 116 GeV/c{sup 2}, is compared with theory predictions. There is good agreement between the data and predictions of Quantum Chromodynamics in Next to Leading Order with the CTEQ6.1M Parton Distribution Functions.
Date: November 1, 2008
Creator: Han, Jiyeon
Object Type: Thesis or Dissertation
System: The UNT Digital Library