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Identifying the sources of subsurface contamination at the Hanford site in Washington using high-precision uranium isotopic measurements

Description: In the mid-1990s, a groundwater plume of uranium (U) was detected in monitoring wells in the B-BX-BY Waste Management Area (WMA) at the Hanford Site in Washington. This area has been used since the late 1940s to store high-level radioactive waste and other products of U fuel-rod processing. Using multiple collector ICP source magnetic sector mass spectrometry (MC ICPMS) high precision uranium isotopic analyses were conducted of samples of vadose zone contamination and of groundwater. The ratios {sup 236}U/{sup 238}U, {sup 234}U/{sup 238}U and {sup 238}U/{sup 235}U are used to distinguish contaminant sources. Based on the isotopic data, the source of the groundwater contamination appears to be related to a 1951 overflow event at tank BX-102 that spilled high level U waste into the vadose zone. The U isotopic variation of the groundwater plume is a result of mixing between contaminant U from this spill and natural background U. Vadose zone U contamination at tank B-110 likely predates the recorded tank leak and can be ruled out as a source of groundwater contamination, based on the U isotopic composition. The locus of vadose zone contamination is displaced from the initial locus of groundwater contamination, indicating that lateral migration in the vadose zone was at least 8 times greater than vertical migration. The time evolution of the groundwater plume suggests an average U migration rate of {approx}0.7-0.8 m/day showing slight retardation relative to a ground water flow of {approx}1 m/day.
Date: March 30, 2004
Creator: Christensen, John N.; Dresel, P. Evan; Conrad, Mark E.; Maher, Kate & DePaolo, Donald J.
Partner: UNT Libraries Government Documents Department

Energy efficient data centers

Description: Data Center facilities, prevalent in many industries and institutions are essential to California's economy. Energy intensive data centers are crucial to California's industries, and many other institutions (such as universities) in the state, and they play an important role in the constantly evolving communications industry. To better understand the impact of the energy requirements and energy efficiency improvement potential in these facilities, the California Energy Commission's PIER Industrial Program initiated this project with two primary focus areas: First, to characterize current data center electricity use; and secondly, to develop a research ''roadmap'' defining and prioritizing possible future public interest research and deployment efforts that would improve energy efficiency. Although there are many opinions concerning the energy intensity of data centers and the aggregate effect on California's electrical power systems, there is very little publicly available information. Through this project, actual energy consumption at its end use was measured in a number of data centers. This benchmark data was documented in case study reports, along with site-specific energy efficiency recommendations. Additionally, other data center energy benchmarks were obtained through synergistic projects, prior PG&E studies, and industry contacts. In total, energy benchmarks for sixteen data centers were obtained. For this project, a broad definition of ''data center'' was adopted which included internet hosting, corporate, institutional, governmental, educational and other miscellaneous data centers. Typically these facilities require specialized infrastructure to provide high quality power and cooling for IT equipment. All of these data center types were considered in the development of an estimate of the total power consumption in California. Finally, a research ''roadmap'' was developed through extensive participation with data center professionals, examination of case study findings, and participation in data center industry meetings and workshops. Industry partners enthusiastically provided valuable insight into current practice, and helped to identify areas where additional ...
Date: March 30, 2004
Creator: Tschudi, William; Xu, Tengfang; Sartor, Dale; Koomey, Jon; Nordman, Bruce & Sezgen, Osman
Partner: UNT Libraries Government Documents Department

High-performance data centers: A research roadmap

Description: This report was developed for the California Energy Commission to document industry input and LBNL research into research topics appropriate for public interest support. Industry experts identified research topics and along with LBNL findings, helped to prioritize the technical areas for future public interest research.
Date: March 30, 2004
Creator: Tschudi, William; Xu, Tengfang; Sartor, Dale & Stein, Jay
Partner: UNT Libraries Government Documents Department

Comparison of quantum confinement effects between quantum wires and dots

Description: Dimensionality is an important factor to govern the electronic structures of semiconductor nanocrystals. The quantum confinement energies in one-dimensional quantum wires and zero-dimensional quantum dots are quite different. Using large-scale first-principles calculations, we systematically study the electronic structures of semiconductor (including group IV, III-V, and II-VI) surface-passivated quantum wires and dots. The band-gap energies of quantum wires and dots have the same scaling with diameter for a given material. The ratio of band-gap-increases between quantum wires and dots is material-dependent, and slightly deviates from 0.586 predicted by effective-mass approximation. Highly linear polarization of photoluminescence in quantum wires is found. The degree of polarization decreases with the increasing temperature and size.
Date: March 30, 2004
Creator: Li, Jingbo & Wang, Lin-Wang
Partner: UNT Libraries Government Documents Department

Atomistic simulations of fcc Pt{sub 75}Ni{sub 25} and Pt{sub 75}Re{sub 25} cubo-octahedral nanoparticles

Description: We have developed interatomic potentials for Pt-Ni and Pt-Re alloys within the modified embedded atom method (MEAM). Furthermore, we applied these potentials to study the equilibrium structures of Pt75Ni25 and Pt75Re25 nanoparticles at T=600 K using the Monte Carlo method. In this work, the nanoparticles are assumed to have disordered fcc cubo-octahedral shapes (terminated by {l_brace}111{r_brace} and {l_brace}100{r_brace} facets) and contain from 586 to 4033 atoms (corresponding to a diameter from 2.5 to 5 nm). It was found that, due to surface segregation, (1) the Pt75Ni25 nanoparticles form a surface-sandwich structure: the Pt atoms are enriched in the outermost and third atomic shells, while the Ni atoms are enriched in the second atomic shell; (2) the equilibrium Pt75Re25 nanoparticles adopt a core-shell structure: a Pt-enriched shell surrounding a Pt-deficient core.
Date: March 30, 2004
Creator: Wang, Guofeng; Van Hove, M.A.; Ross, P.N. & Baskes, M.I.
Partner: UNT Libraries Government Documents Department

First principle thousand atom quantum dot calculations

Description: A charge patching method and an idealized surface passivation are used to calculate the single electronic states of IV-IV, III-V, II-VI semiconductor quantum dots up to a thousand atoms. This approach scales linearly and has a 1000 fold speed-up compared to direct first principle methods with a cost of eigen energy error of about 20 meV. The calculated quantum dot band gaps are parametrized for future references.
Date: March 30, 2004
Creator: Wang, Lin-Wang & Li, Jingbo
Partner: UNT Libraries Government Documents Department

RESORCINOL-FORMALDEHYDE ADSORPTION OF CESIUM (Cs+) FROM HANFORD WASTE SOLUTIONS-PART I: BATCH EQUILIBRIUM STUDY

Description: Batch equilibrium measurements were conducted with a granular Resorcinol-Formaldehyde (RF) resin to determine the distribution coefficients (Kds) for cesium. In the tests, Hanford Site actual waste sample containing radioactive cesium and a pretreated waste sample that was spiked with non-radioactive cesium were used. Initial concentrations of non-radioactive cesium in the waste sample were varied to generate an equilibrium isotherm for cesium. Two additional tests were conducted using a liquid to solid phase ratio of 10 and a contact time of 120 hours. The measured distribution coefficient (Kd) for radioactive cesium (137Cs) was 948 mL/g; the Kd for non-radioactive cesium (133Cs) was 1039 mL/g. The Kd for non-radioactive cesium decreased from 1039 to 691 mL/g as the initial cesium concentration increased. Very little change of the Kd was observed at initial cesium concentrations above 64 mg/mL. The maximum sorption capacity for cesium on granular RF resin was 1.17 mmole/g dry resin. T his value was calculated from the fit of the equilibrium isotherm data to the Dubinin-Radushkevich equation. Previously, a total capacity of 2.84 mmole/g was calculated by Bibler and Wallace for air-dried RF resin.
Date: March 30, 2004
Creator: Hassan, Neguibm
Partner: UNT Libraries Government Documents Department

Effects of stacking faults on the electronic structures of quantum rods

Description: Atomistic semiempirical pseudopotential method is used to study the effects of stacking faults in a wurtzite structure quantum rod. It is found that a single stacking fault can cause a 10-50 meV change in the conduction state eigen energy, and a localization in the electron wave function. However, the effects on the hole eigen energies and wave functions are very small.
Date: March 30, 2004
Creator: Wang, Lin-Wang
Partner: UNT Libraries Government Documents Department

Development and evaluation of fully automated demand response in large facilities

Description: This report describes the results of a research project to develop and evaluate the performance of new Automated Demand Response (Auto-DR) hardware and software technology in large facilities. Demand Response (DR) is a set of activities to reduce or shift electricity use to improve electric grid reliability, manage electricity costs, and ensure that customers receive signals that encourage load reduction during times when the electric grid is near its capacity. The two main drivers for widespread demand responsiveness are the prevention of future electricity crises and the reduction of electricity prices. Additional goals for price responsiveness include equity through cost of service pricing, and customer control of electricity usage and bills. The technology developed and evaluated in this report could be used to support numerous forms of DR programs and tariffs. For the purpose of this report, we have defined three levels of Demand Response automation. Manual Demand Response involves manually turning off lights or equipment; this can be a labor-intensive approach. Semi-Automated Response involves the use of building energy management control systems for load shedding, where a preprogrammed load shedding strategy is initiated by facilities staff. Fully-Automated Demand Response is initiated at a building or facility through receipt of an external communications signal--facility staff set up a pre-programmed load shedding strategy which is automatically initiated by the system without the need for human intervention. We have defined this approach to be Auto-DR. An important concept in Auto-DR is that a facility manager is able to ''opt out'' or ''override'' an individual DR event if it occurs at a time when the reduction in end-use services is not desirable. This project sought to improve the feasibility and nature of Auto-DR strategies in large facilities. The research focused on technology development, testing, characterization, and evaluation relating to Auto-DR. This evaluation also ...
Date: March 30, 2004
Creator: Piette, Mary Ann; Sezgen, Osman; Watson, David S.; Motegi, Naoya; Shockman, Christine & ten Hope, Laurie
Partner: UNT Libraries Government Documents Department

Improved Method for Quantifying Nonvolatile Residues on Surfaces and in Liquids

Description: The objective of the project was to develop an improved method to quantify nonvolatile residues on surfaces and in liquids. The project accomplishments are summarized below: (1) ERA Systems, Inc., The MESERAN Company has designed, developed, built, evaluated, tested, and delivered MicroSolventEvaporator systems to KCP, Astro Pak, and Lockheed Martin, that automatically deposit and evaporate successive small quantities (5-10 microliters) of solvents onto clean reference surfaces. (2) ERA Systems, Inc., The MESERAN Company, and KCP have designed, procured, and evaluated stainless steel disks with specific machined grooves to be used as reference surfaces with the MicroSolventEvaporator and MESERAN Analyzers. (3) KCP evaluated various cleaning processes to easily clean the reference surfaces to acceptable levels. Even though some methods (or a combination of methods) may have worked better than others, an easy method that most companies could use to acceptably clean the disks was desired. Aqueous ultrasonic cleaning with Dirl Lum 603 (30 g per liter concentration) followed by flowing DI water and ultrasonic DI water rinses, nitrogen blow drying, and baking in a HEPA filtered oven at 220 F for 30 minutes proved to be a relatively simple method that most companies could use. (4) KCP developed calibrations of several contaminants on the chosen reference substrates so the MESERAN data could be converted into quantifiable amounts of contamination. (5) KCP performed a prove-in of the MicroSolventEvaporator in conjunction with the MESERAN Analyzer and compared the results to gravimetric data. The method worked and was able to provide data at low contamination levels that can not be reliably obtained gravimetrically. (6) Astro Pak and Lockheed Martin have done limited testing at their facilities. The MESERAN Company has agreed to let them keep the units for awhile so they can continue to perform tests to prove-in the process at their facilities even ...
Date: March 30, 2004
Creator: Benkovich, M. G.
Partner: UNT Libraries Government Documents Department

Internal Revenue Service: Assessment of Fiscal Year 2005 Budget Request and 2004 Filing Season Performance

Description: Testimony issued by the General Accounting Office with an abstract that begins "Effective tax administration requires a combination of quality customer service to help those who want to comply, and effective enforcement measures against those who do not. For the last few years, we have been reporting on improvements in taxpayer service and declines in enforcement. With respect to IRS's fiscal year 2005 budget request, the Subcommittee asked GAO to assess whether (1) IRS will be able to allocate more resources to enforcement, and (2) Business Systems Modernization (BSM) and other technology efforts will deliver cost savings and efficiencies in the immediate future. For the 2004 filing season performance, GAO was asked to assess IRS's performance in processing returns and providing assistance to taxpayers."
Date: March 30, 2004
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department

Critical Infrastructure Protection: Challenges and Efforts to Secure Control Systems

Description: Testimony issued by the General Accounting Office with an abstract that begins "Computerized control systems perform vital functions across many of our nation's critical infrastructures. For example, in natural gas distribution, they can monitor and control the pressure and flow of gas through pipelines. In October 1997, the President's Commission on Critical Infrastructure Protection emphasized the increasing vulnerability of control systems to cyber attacks. At the request of the House Committee on Government Reform, Subcommittee on Technology, Information Policy, Intergovernmental Relations and the Census, this testimony will discuss GAO's March 2004 report on potential cyber vulnerabilities, focusing on (1) significant cybersecurity risks associated with control systems (2) potential and reported cyber attacks against these systems (3) key challenges to securing control systems, and (4) efforts to strengthen the cybersecurity of control systems."
Date: March 30, 2004
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department

Energy Employees Compensation: Obstacles Remain in Processing Cases Efficiently and Ensuring a Source of Benefit Payments

Description: Testimony issued by the General Accounting Office with an abstract that begins "The Department of Energy (Energy) and its predecessor agencies and contractors have employed thousands of people in the nuclear weapons production complex. Some employees were exposed to toxic substances, including radioactive and hazardous materials, during this work, and many subsequently developed illnesses. Subtitle D of the Energy Employees Occupational Illness Compensation Program Act of 2000 allows Energy to help its contractor employees file state workers' compensation claims for illnesses determined by a panel of physicians to be caused by exposure to toxic substances in the course of employment at an Energy facility. Congress mandated that GAO study the effectiveness of the benefit program under Subtitle D of this Act. This testimony is based on GAO's ongoing work on this issue and focuses on four key areas: (1) the number, status, and characteristics of claims filed with Energy; (2) the extent to which Energy policies and procedures help employees file timely claims for these state benefits; (3) the extent to which there will be a "willing payer" of workers' compensation benefits, that is, an insurer who--by order from or agreement with Energy--will not contest these claims; and (4) a framework that could be used for evaluating possible options for changing the program."
Date: March 30, 2004
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department

Federal Food Safety and Security System: Fundamental Restructuring Is Needed to Address Fragmentation and Overlap

Description: Testimony issued by the General Accounting Office with an abstract that begins "The safety of the U.S. food supply is governed by a highly complex system of more than 30 laws administered by 12 agencies. In light of the recent focus on government reorganization, it is time to ask whether the current system can effectively and efficiently respond to today's challenges. At the request of the Subcommittee on Civil Service and Agency Organization, we reviewed and summarized our work on the safety and security of the food supply regarding (1) the fragmented legal and organizational structure of the federal food safety system, (2) the consequences of overlapping and inconsistent inspection and enforcement, and (3) options for consolidating food safety functions."
Date: March 30, 2004
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department

Aviation Security: Improvement still Needed in Federal Aviation Security Efforts

Description: Testimony issued by the General Accounting Office with an abstract that begins "The security of the nation's commercial aviation system has been a long-standing concern. Following the events of September 11, 2001, Congress enacted numerous aviation security improvements designed to strengthen aviation security, including the development of a passenger prescreening system and the federalization of airport screeners. Despite these changes, challenges continue to face the Department of Homeland Security (DHS) and the Transportation Security Administration (TSA) efforts to improve aviation security. GAO was asked to summarize the results of previous and ongoing aviation security work. These include: (1) the development of CAPPS II to assist in identifying high-risk passengers, (2) the management of passenger and baggage screening programs, (3) the operations of the Federal Air Marshal Service, and (4) other aviations security related efforts, such as cargo, that remain a concern."
Date: March 30, 2004
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department

National Park Service: A More Systematic Process for Establishing National Heritage Areas and Actions to Improve Their Accountability Are Needed

Description: Testimony issued by the General Accounting Office with an abstract that begins "The Congress has established, or "designated," 24 national heritage areas to recognize the value of their local traditions, history, and resources to the nation's heritage. These areas, including public and private lands, receive funds and assistance through cooperative agreements with the National Park Service, which has no formal program for them. They also receive funds from other agencies and nonfederal sources, and are managed by local entities. Growing interest in new areas has raised concerns about rising federal costs and the risk of limits on private land use. GAO was asked to review the (1) process for designating heritage areas, (2) amount of federal funding to these areas, (3) process for overseeing areas' activities and use of federal funds, and (4) effects, if any, they have on private property rights."
Date: March 30, 2004
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department

Synthesis of 6-acrylamido-4-(2-[18F]fluoroanilino)quinazoline: Aprospective irreversible EGFR binding probe

Description: Acrylamido-quinazolines substituted at the 6-position bindirreversibly to the intracellular ATP binding domain of the epidermalgrowth factor receptor (EGFR). A general route was developed forpreparing 6-substituted-4-anilinoquinazolines from [18F]fluoroanilinesfor evaluation as EGFR targeting agents with PET. By a cyclizationreaction, 2-[18F]fluoroaniline was reacted withN'-(2-cyano-4-nitrophenyl)-N,N-dimethylimidoformamide to produce6-nitro-4-(2-[18F]fluoroanilino)quinazoline in 27.5 percentdecay-corrected radiochemical yield. Acid mediated tin chloride reductionof the nitro group was achieved in 5 min (80 percent conversion) andsubsequent acylation with acrylic acid gave6-acrylamido-4-(2-[18F]fluoroanilino)quinazoline in 8.5 percentdecay-corrected radiochemical yield, from starting fluoride, in less than2 hours.
Date: March 30, 2004
Creator: Vasdev, Neil; Dorff, Peter N.; Gibbs, Andrew R.; Nandanan,Erathodiyil; Reid, Leanne M.; O'Neil, James P. et al.
Partner: UNT Libraries Government Documents Department