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The LCLS X-Ray FEL at SLAC
The design status and R and D plan of a 1.5 Angstrom SASE-FEL at SLAC, called the Linac Coherent Light Source (LCLS), are described. The LCLS utilizes one third of the SLAC linac for the acceleration of electrons to about 15 GeV. The FEL radiation is produced in a long undulator and is directed to an experimental area for its utilization. The LCLS is designed to produce 300 fsec long radiation pulses at the wavelength of 1.5 Angstrom with 9 GW peak power. This radiation has much higher brightness and coherence, as well as shorter pulses, than present 3rd generation sources. It is shown that such leap in performance is now within reach, and is made possible by the advances in the physics and technology of photo-injectors, linear accelerators, insertion devices and free-electron lasers.
Date:
February 9, 1999
Creator:
Cornacchia, Massimo
Object Type:
Report
System:
The UNT Digital Library
Bond Strength of Cementitious Borehole Plugs in Welded Tuff
Axial loads on plugs or seals in an underground repository due to gas, water pressures and temperature changes induced subsequent to waste and plug emplacement lead to shear stresses at the plug/rock contact. Therefore, the bond between the plug and rock is a critical element for the design and effectiveness of plugs in boreholes, shafts or tunnels. This study includes a systematic investigation of the bond strength of cementitious borehole plugs in welded tuff. Analytical and numerical analysis of borehole plug-rock stress transfer mechanics is performed. The interface strength and deformation are studied as a function of Young`s modulus ratio of plug and rock, plug length and rock cylinder outside-to-inside radius ratio. The tensile stresses in and near an axially loaded plug are analyzed. The frictional interface strength of an axially loaded borehole plug, the effect of axial stress and lateral external stress, and thermal effects are also analyzed. Implications for plug design are discussed. The main conclusion is a strong recommendation to design friction plugs in shafts, drifts, tunnels or boreholes with a minimum length to diameter ratio of four. Such a geometrical design will reduce tensile stresses in the plug and in the host rock to a level …
Date:
February 1, 1991
Creator:
Akgun, H. & Daemen, J. J. K.
Object Type:
Report
System:
The UNT Digital Library
Task 3.14 - Demonstration of Technologies for Remote Power Generation in Alaska
In over 165 villages in Alaska, the use of fossil fuel supplies or renewable energy resources could greatly reduce the cost of electricity and space heating. Currently, diesel generators are the most commonly used electrical generating systems; however, high fuel costs result in extremely high electrical power costs reIative to the lower 48 states. The reduction of fuel costs associated with the use of indigenous, locally available fuels running modular, high-efficiency power- generating systems would be extremely beneficial.
Date:
February 1, 1998
Creator:
Jones, Michael L.
Object Type:
Report
System:
The UNT Digital Library
Environmental Control Technology
Operations and maintenance continued this month at the Electric Power Research Institute's (EPRI's) Environmental Control Technology Center (ECTC). Testing for the Hazardous Air Pollutants (HAP) study was conducted using the Carbon Injection System (the 4.0 MW Spray Dryer Absorber and the Pulse-Jet Fabric Filter). Testing also continued across the B&W/CHX Heat Exchanger this month as the effects of increased particulate loading are being studied. The 1.0 MW Cold-Side Selective Catalytic Reduction (SCR) unit and the 4.0 MW Pilot Wet Scrubber remained idle this month in a cold-standby mode and were inspected regularly. On September 13, 1996, the ECTC completed an independent test block for a third-party company, Air Purification Inc. (API). For this testing, the ECTC's staff (O&M and Testing) were contracted to conduct performance and validation testing across a new, integrated emissions control device, the Rotorfilter{trademark}. This testing was conducted for a thirty (30) day period simultaneously with the B&W/CHX test block. The HAP testing resumed as this third-party test block was completed. Testing in September at the Electric Power Research Institute's (EPRI's) Environmental Control Technology Center (ECTC) included tests from the Pilot Trace Elements Removal (TER) test block as part of EPRI's overall program to develop control technology …
Date:
February 10, 1997
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Ceramic breeder materials : status and needs.
The tritium breeding blanket is one of the most important components of a fusion reactor because it directly involves both energy extraction and tritium production, both of which are critical to fusion power. Because of their overall desirable properties, lithium-containing ceramic solids are recognized as attractive tritium breeding materials for fusion reactor blankets. Indeed, their inherent thermal stability and chemical inertness are significant safety advantages. In numerous in-pile experiments, these materials have performed well, showing good thermal stability and good tritium release characteristics. Tritium release is particularly facile when an argon or helium purge gas containing hydrogen, typically at levels of about 0.1%, is used. However, the addition of hydrogen to the purge gas imposes a penalty when it comes to recovery of the tritium produced in the blanket. In particular, a large amount of hydrogen in the purge gas will necessitate a large multiple-stage tritium purification unit, which could translate into higher costs. Optimizing tritium release while minimizing the amount of hydrogen necessary in the purge gas requires a deeper understanding of the tritium release process, especially the interactions of hydrogen with the surface of the lithium ceramic. This paper reviews the status of ceramic breeder research and highlights …
Date:
February 2, 1998
Creator:
Johnson, C. E.
Object Type:
Article
System:
The UNT Digital Library
Characterization of transient gain x-ray lasers
We have performed numerical simulations of the transient collisional excitation Ni-like Pd 4d {r_arrow} 4p J = 0 {r_arrow} 1 147 {angstrom} laser transition recently observed at Lawrence Livermore National Laboratory (LLNL). The high gain {approximately}35 cm results from the experiment are compared with detailed modeling simulations from the 1-D RADEX code in order to better understand the main physics issues affecting the measured gain and x-ray laser propagation along the plasma column. Simulations indicate that the transient gain lifetime associated with the short pulse pumping and refraction of the x-ray laser beam out of the gain region are the main detrimental effects. Gain lifetimes of {approximately}7 ps(1/e decay) are inferred from the smoothly changing gain experimental observations and are in good agreement with the simulations. Furthermore, the modeling results indicate the presence of a longer-lived but lower gain later in time associated with the transition from transient to quasi-steady state excitation.
Date:
February 7, 1999
Creator:
Dunn, J; Osterheld, A & Shlyaptsev, V
Object Type:
Article
System:
The UNT Digital Library
Predictive Model and Methodology for Heat Treatment Distortion
The purpose of this project was to develop a modeling methodology and software tool to simulate and predict the results of heat treatment, especially distortion. In order to develop a simulation tool, significant technical, analytical, and experimental resources were needed. This task was too large and complex for just one company or organization to address. To this end, 4 national laboratories (Los Alamos National Laboratory, Lawrence Livermore National Laboratory, the Oak Ridge National Laboratory/Y-12 Plant, and Sandia National Laboratories) and many partners working through NCMS tackled this effort. The participants through NCMS were Ford Motor Company, General Motors Corporation, The Torrington Company, Deformation Control Technologies, The MacNeal-Schwindler Corp. IIT Research Institute, the Gear Research Institute, U.S. Benet Laboratories (Army), and the Colorado School of Mines. For the purpose of this report only those items pertinent to the Oak Ridge National Laboratory/Y-12 Plant participation in this CRADA will be highlighted along with those related items directly related to these specific efforts that were accomplished by the partners.
Date:
February 17, 1998
Creator:
Ludtka, G.M.
Object Type:
Report
System:
The UNT Digital Library
Rock mechanics contributions from defense programs
An attempt is made at illustrating the many contributions to rock mechanics from US defense programs, over the past 30-plus years. Large advances have been achieved in the technology-base area covering instrumentation, material properties, physical modeling, constitutive relations and numerical simulations. In the applications field, much progress has been made in understanding and being able to predict rock mass behavior related to underground explosions, cratering, projectile penetration, and defense nuclear waste storage. All these activities stand on their own merit as benefits to national security. But their impact is even broader, because they have found widespread applications in the non-defense sector; to name a few: the prediction of the response of underground structures to major earthquakes, the physics of the earth`s interior at great depths, instrumentation for monitoring mine blasting, thermo-mechanical instrumentation useful for civilian nuclear waste repositories, dynamic properties of earthquake faults, and transient large-strain numerical modeling of geological processes, such as diapirism. There is not pretense that this summary is exhaustive. It is meant to highlight success stories representative of DOE and DOD geotechnical activities, and to point to remaining challenges.
Date:
February 1, 1992
Creator:
Heuze, F.E.
Object Type:
Article
System:
The UNT Digital Library
Transport of neptunium through Yucca Mountain tuffs
Neptunium has a high solubility in groundwaters from Yucca Mountain [1]. Uranium in nuclear reactors produces {sup 237}Np which has a half-life of 2.1 4 {times} 10{sup 6} years. Consequently, the transport of {sup 237}Np through tuffs is of major importance in assessing the performance of a high-level nuclear waste repository at Yucca Mountain. The objective of this work is to determine the amount of Np retardation that is provided by the minerals in Yucca Mountain tuffs as a function of groundwater chemistry.
Date:
February 1, 1993
Creator:
Triay, I. R.; Robinson, B. A.; Mitchell, A. J.; Overly, C. M. & Lopez, R. M.
Object Type:
Article
System:
The UNT Digital Library
Calendar year 1994 groundwater quality report for the Upper East Fork Poplar Creek Hydrogeologic Regime, Y-12 Plant, Oak Ridge, Tennessee: 1994 groundwater quality data and calculated rate of contaminant migration
This annual groundwater quality report (GWQR) contains groundwater and surface water quality data obtained during the 1994 calendar year (CY) at several waste-management facilities and a petroleum fuel underground storage tank (UST) site associated with the US Department of Energy (DOE) Y-12 Plant located on the DOE Oak Ridge Reservation (ORR) southeast of Oak Ridge, Tennessee. The sites addressed by this document are located within the Upper East Fork Poplar Creek Hydrogeologic Regime (East Fork Regime). The East Fork Regime, which is one of three hydrogeologic regimes defined for the purposes of groundwater quality monitoring at the Y-12 Plant, encompasses the Y-12 Plant. The regime extends west from a surface water and shallow groundwater divide located near the west end of the plant to Scarboro Road (directions in this report are in reference to the Y-12 Plant grid system unless otherwise noted). The Environmental Management Department of the Y-12 Plant Health, Safety, Environment, and Accountability (HSEA) Organization manages the groundwater monitoring activities in each regime as part of the Y-12 Plant Groundwater Protection Program (GWPP). The purpose of the GWPP is to characterize the hydrogeology and to monitor groundwater quality at the Y-12 Plant and surrounding area to provide for …
Date:
February 1, 1995
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Proceedings of the 21st DOE/NRC Nuclear Air Cleaning Conference; Sessions 1--8
Separate abstracts have been prepared for the papers presented at the meeting on nuclear facility air cleaning technology in the following specific areas of interest: air cleaning technologies for the management and disposal of radioactive wastes; Canadian waste management program; radiological health effects models for nuclear power plant accident consequence analysis; filter testing; US standard codes on nuclear air and gas treatment; European community nuclear codes and standards; chemical processing off-gas cleaning; incineration and vitrification; adsorbents; nuclear codes and standards; mathematical modeling techniques; filter technology; safety; containment system venting; and nuclear air cleaning programs around the world. (MB)
Date:
February 1, 1991
Creator:
First, M. W.
Object Type:
Article
System:
The UNT Digital Library
Target rapidity baryon distributions in {sup 28}Si + {sup 197}Au and {sup 197}Au + {sup 197}Au collisions at 14.6 and 11.7 A{center_dot}GeV/c
Proton and deuteron kinetic energy spectra have been measured at target rapidities for both minimum bias and central collisions of 14.6 A{center_dot}GeV/c {sup 28}Si and 11.7 A{center_dot}GeV/c {sup 197}Au beams with a {sup 197}Au target. The spectra were measured from a low energy threshold of approximately E{sub kin}=35 MeV to well over 200 MeV for laboratory angles of 50{degree} to 130{degree} ({vert_bar}{eta}{vert_bar} {le}0.76). The acceptance-corrected spectra have been fit over a limited range of kinetic energies using a Boltzmann distribution. The integrated yields and the inverse slope parameters are presented as a function of centrality for the {sup 28}Si + {sup 197}Au reaction and as a function of trigger for the {sup 197}Au + {sup 197}Au reaction. These quantities are also compared with the proton spectra generated using both the ARC and RQMD codes.
Date:
February 25, 1993
Creator:
Sangster, T.C.; Costales, J.B.; Namboodiri, M.N. & Collaboration, E802
Object Type:
Article
System:
The UNT Digital Library
Opto-mechanical design and fabrication services. Final report
Each of the seven tasks defined under this contract are discussed here. They include: (1) design support for an x-ray spectrometer for the ``Panchuela`` down-hole experiment at the Nevada Test Site; (2) development and demonstration of an optical alignment method for aligning the 180 degree bend achromatic magnetic section of the Ground Test Accelerator; (3) development of magnet support and manipulation concepts for the 17 magnets of the Ground Test Accelerator; (4) design support for the triplett magnet telescope assembly and its support structure (Neutral Particle Beam Program); (5) design and support for the beam diagnostic system for the Argonne Particle Beam experiment; (6) conceptual design for the modification of an Antares Marx tank for use in the Aurora Laser Program; and (7) design of poloidal gap for the Los Alamos ZTH reversed-field pinch machine.
Date:
February 28, 1988
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Engineered barrier environment, Yucca Mountain
The US Department of Energy is studying the suitability of Yucca Mountain (YM) as a potential nuclear waste repository site. Environmental conditions are important to engineered barrier system (EBS) design, materials testing, selection, design criteria, waste-form characterization, and performance assessment. Yucca Mountain is located in uninhabited desert which results in an environmental framework (unsaturated conditions, and sorptive properties of the rock materials) that is generally favorable for waste disposal. However, waste package (WP) and engineered barrier system (EBS) design concepts, including materials testing and selection, design criteria development, waste-form characterization, and performance assessments all require a specific and detailed understanding of the environmental conditions that will interact with the WP/EBS. Environmental conditions assessments from a series of laboratory and modeling studies have been conducted which provide the current understanding of the near-field environmental conditions at YM that not only exist now but will exist in the future. Because the environmental conditions can change with time, emphasis of the investigations were on processes and changed (not ambient) conditions.
Date:
February 1, 1993
Creator:
Wilder, D. G.
Object Type:
Article
System:
The UNT Digital Library
Scale-up of mild gasification to a process development unit. Progress report for August 21--November 20, 1994
The overall objective of this project is to develop the IGT Mild-Gasification (MILDGAS) process for near-term commercialization. The specific objectives of the program are to: design, construct, and operate a 24-tons/day adiabatic process development unit (PDU) to obtain process performance data suitable for further design scaleup; obtain large batches of coal-derived co-products for industrial evaluation; prepare a detailed design of a demonstration unit; and develop technical and economic plans for commercialization of the MILDGAS process. The 1 ton/hr PDU facility that is to be constructed is comprised of a 2.5-ft ID adiabatic gasifier for the production of gases, coal liquids, and char; a three-stage condensation train to condense and store the liquid products; and coal feeding and char handling equipment. The facility will also incorporate support equipment for environmentally acceptable disposal of process waste. This quarter work included clearing, grubbing, grading and backfilling of the site, installation of culverts and fencing, placing of the main structure foundation and truck pad, and installation of gravel on the areas that will later be blacktopped. Also this quarter, a contract for the emissions and control package was awarded to Calidus Technologies. In addition, agreement with Central Illinois Power Service on the electrical supply …
Date:
February 1, 1995
Creator:
Doane, E. P.; Carty, R. H. & Foster, H.
Object Type:
Report
System:
The UNT Digital Library
Functions and requirements for the INEL light duty utility arm sampler end effector
This sampler end effector system functions and requirements document defines the system functions that the end effector must perform as well as the requirements the design must meet. Safety, quality assurance, operations, environmental conditions, and regulatory requirements have been considered. The main purpose of this document is to provide a basis for the end effector engineering, design, and fabrication activities. The document shall be the living reference document to initiate the development activities and will be updated as system technologies are finalized.
Date:
February 1, 1995
Creator:
Pace, D.P. & Barnes, G.E.
Object Type:
Report
System:
The UNT Digital Library
Evaluation of Low and High Frequency Sound for Enhancing Fish Screening Facilities to Protect Outmigrating Salmonids.
The need to provide passage and protective screens at irrigation diversions has always been a necessary part of the Columbia River Basin Fish and Wildlife Program (NPPC 1984, 1987, 1994). From 1985 through 1990, fish protection facilities in large irrigation diversions throughout the Columbia Basin, especially in the Yakima Basin, were updated. After 1990, fish protection efforts turned to installation of new facilities on unscreened diversions and to repair and upgrade of older facilities. The screening program also includes funds to monitor and evaluate the facilities. The screen evaluations indicate they are an effective means for protecting juvenile fish larger than 40 mm in length. As state and federal agencies change screening criteria to protect smaller fish (e.g., bull trout fry), the physical barrier may not always be effective. Screen mesh small enough to protect fish may be vulnerable to frequent plugging. Gap tolerances on side and bottom seals may be difficult to install and maintain. Physical barrier screens can be enhanced with behavioral barriers that cause fish to avoid a hazard. Behavioral barriers may consist of sound generator, strobe lights, bubble curtains, or electrical barriers. State of Oregon House Bill 3112 states that "Standards and criteria shall address the …
Date:
February 1998
Creator:
Mueller, Robert P.; Neitzel, Duane A. & Mavros, William V.
Object Type:
Report
System:
The UNT Digital Library
Construction project data sheet for the environmental, safety and health upgrades: Phase 3 Program FY 1991 line item
This document is prepared in tabular form and depicts costs and safety analysis of a number of Mound construction projects. Some projects described include solvent waste handling, environmental buffer zone, and sanitary treatment plant.
Date:
February 3, 1989
Creator:
Hunter, M. R.
Object Type:
Report
System:
The UNT Digital Library
Point defect production, geometry and stability in silicon: A molecular dynamics simulation study
We present results of molecular dynamics computer simulation studies of the threshold energy for point defect production in silicon. We employ computational cells with 8000 atoms at ambient temperature of 10 K that interact via the Stillinger-Weber potential. Our simulations address the orientation dependence of the defect production threshold as well as the structure and stability of the resulting vacancy-interstitial pairs. Near the <111> directions, a vacancy tetrahedral-interstitial pair is produced for 25 eV recoils. However, at 30 eV recoil energy, the resulting interstitial is found to be the <110> split dumbbell configuration. This Frenkel pair configuration is lower in energy than the former by 1.2 eV. Moreover, upon warming of the sample from 10 K the tetrahedral interstitial converts to a <110> split before finally recombining with the vacancy. Along <100> directions, a vacancy-<110> split interstitial configuration is found at the threshold energy of 22 eV. Near <110> directions, a wide variety of closed replacement chains are found to occur for recoil energies up to 45 eV. At 45 eV, the low energy vacancy-<l 10> split configuration is found. At 300 K, the results are similar. We provide details on the atomic structure and relaxations near these defects as …
Date:
February 1, 1994
Creator:
Caturla, M.J.; Rubia, T.D. de la & Gilmer, G.H.
Object Type:
Article
System:
The UNT Digital Library
Robust controller design of four wheel steering systems using mu synthesis techniques
In this paper, a linearized four wheel steering (4WS) system model is deduced and then modified into a form which is appropriate for applying Matlab {mu} Toolbox to design robust controller. Several important topics are discussed in detail, such as (1) how to make system set-up match Matlab {mu} Toolbox requirement, (2) how to select weights based on plant`s uncertainty, (3) how to solve controller discretization problem, and (4) how to adjust the system so that the conditions necessary for using a state-space formula to solve H{infinity} optimal (sub-optimal) problem and performing the Matlab {mu} Toolbox D--K iteration procedure are satisfied. Finally simulation results of robust controller and a PID controller are compared.
Date:
February 27, 1995
Creator:
Gao, X.; McVey, B. D. & Tokar, R. L.
Object Type:
Article
System:
The UNT Digital Library
Beam tests of the 12 MHz RFQ RIB injector for ATLAS.
In recent tests without beam, the Argonne 12 MHz split-coaxial radio-frequency quadruple (RFQ) achieved a cw intervane voltage of more than 100 kV, the design operating voltage for the device. This voltage is sufficient for the RFQ to function as the first stage of a RIB injector for the Argonne Tandem Linear Accelerator System (ATLAS). Previously reported beam dynamics calculations for the structure predict longitudinal emittance growth of only a few keV{center_dot}ns for beams of mass 132 and above with transverse emittance of 0.27 {pi} mm{center_dot}mrad (normalized). Such beam quality is not typical of RFQ devices. The work reported here is preparation for tests with beams of mass up to 132. Beam diagnostic stations are being developed to measure the energy gain and beam quality of heavy ions accelerated by the RFQ using the Dynamitron accelerator facility at the ANL Physics Division as the injector. Beam diagnostic development includes provisions for performing the measurements with both a Si charged-particle detector and an electrostatic energy spectrometer system.
Date:
February 8, 1999
Creator:
Kaye, R. A.
Object Type:
Article
System:
The UNT Digital Library
Criticality safety evaluation for K Area Disassembly Basin cleanup
Preparations are currently being made to remove sludge from the Disassembly Basin in all reactor areas. Because this sludge contains fissile isotopes, it is necessary to perform a criticality safety evaluation for the planned activities. A previous evaluation examined the criticality safety aspects of the sludge removal process for L Area. This document addresses the criticality safety aspects of the K Area Disassembly Basin cleanup work. The K Area Disassembly Basin cleanup will involve, as a first step, pumping the basin sludge into the Monitor Basin portion of the Disassembly Basin. From the Monitor Basin, the sludge will be pumped into tanks or containers for permanent disposition. The criticality safety evaluation discussed in this document covers the transfer of the sludge to the Monitor Basin.
Date:
February 1, 1994
Creator:
Rosser, M.A.
Object Type:
Report
System:
The UNT Digital Library
Site characterization data from the Area 5 science boreholes, Nevada Test Site, Nye County, Nevada
The Science Borehole Project consists of eight boreholes that were drilled (from 45.7 m [150 ft] to 83.8 m [275 ft] depth) in Area 5 of the Nevada Test Site, Nye County, Nevada, on behalf of the US Department of Energy. These boreholes are part of the Area 5 Site Characterization Program developed to meet data needs associated with regulatory requirements applicable to the disposal of low-level and mixed waste at this site. This series of boreholes was specifically designed to characterize parameters controlling near-surface gas transport and to monitor changes in these and liquid flow-related parameters over time. These boreholes are located along the four sides of the approximately 2.6-km{sup 2} (1-mi{sup 2}) Area 5 Radioactive Waste Management Site to provide reasonable spatial coverage for sampling and characterization. Laboratory testing results of samples taken from core and drill cuttings are reported.
Date:
February 1, 1995
Creator:
Blout, D.O.; Hammermeister, P. & Zukosky, K.A.
Object Type:
Report
System:
The UNT Digital Library
Role of underground testing to determine suitability of Yucca Mountain as a potential repository site
A brief description of the Exploratory Shaft based site characterization testing program for the Yucca Mountain Project of the permanent disposal of high level radioactive waste is briefly described in this paper. Details of the testing program are presented in the DOE-issued Site Characterization Plan. Overview of the current planning process and status of various activities is briefly described. This study will reevaluate the mining method, ESF location and any changes in the ESF testing program. 2 refs., 2 figs., 1 tab.
Date:
February 1, 1990
Creator:
Kalia, H.N.
Object Type:
Article
System:
The UNT Digital Library