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Design and construction of a pipeline for transfer of radioactive sodium at Argonne National Laboratory-West.
Experimental Breeder Reactor-II (EBR-II), an experimental sodium cooled fast breeder reactor located at Argonne National Laboratory-West (ANL-W), was shut down in 1994, and has since been defueled in preparation for final plant closure. Approximately 100,000 gallons of liquid sodium is contained in the primary and secondary cooling systems of the EBR-II plant. The liquid sodium must be drained from the reactor systems during closure of the plant to place the reactor plant in an industrially and radiologically safe condition for long term storage or dismantlement. Because the liquid sodium is a listed waste under the Resource Conservation Recovery Act (RCRA), it is not suitable for disposal. It therefore must be transferred to the Sodium Process Facility (SPF), which is located approximately nine hundred feet from the reactor complex, where it will be processed into a non-reactive form, suitable for land disposal in Idaho. To facilitate this transfer, a heated pipeline for carrying liquid sodium metal from EBR-II to the SPF was designed and installed. The SPF was originally designed and built to process primary sodium from the Fermi-1 reactor. The sodium is stored at ANL-W in 55 gallon drums. Design of the SPF did not originally accommodate processing of EBR-II …
Date:
February 25, 1998
Creator:
Baily, C. E.
Object Type:
Article
System:
The UNT Digital Library
Analysis of the ATW fuel cycle using the REBUS-3 code system.
Partitioning and transmutation strategies are under study in several countries as a means of reducing the long-term hazards of spent fuel and other high-level nuclear waste. Various reactor and accelerator-driven system concepts have been proposed to transmute the long-lived radioactive nuclei of waste into stable or short-lived species. Among these concepts, the accelerator-driven transmutation of waste (ATW) system has been proposed by LANL for rapid destruction of transuranic actinides and long-lived fission products ({sup 99}Tc and {sup 129}I).The current reference ATW concept employs a subcritical, liquid metal cooled, fast-spectrum nuclear subsystem. Because the discharged fuel is recycled, analysis of ATW nuclear performance requires modeling of the external cycle as well as the in-core fuel management. The fuel cycle analysis of ATW can be performed rigorously using Monte Carlo calculations coupled with detailed depletion calculations. However, the inefficiency of this approach makes it impractical, particularly in view of (a) the large number of fuel cycle calculations needed for design optimization and (b) the need to represent complex in-core and out-of-core fuel cycle operations. To meet the need for design-oriented capabilities, tools previously developed for fast reactor calculations are being adapted for application to ATW. Here we describe the extension and application …
Date:
June 25, 1999
Creator:
Khalil, H. S. & Yang, W. S.
Object Type:
Article
System:
The UNT Digital Library
Petroleum supply monthly, August 1995 with data for June 1995
Data presented in the PSM describe the supply and disposition of petroleum products in the United States and major US geographic regions. The data series describe production, imports and exports, inter-Petroleum Administration for Defense (PAD) District movements, and inventories by the primary suppliers of petroleum products in the United States (50 States and the District of Columbia). The reporting universe includes those petroleum sectors in primary supply. Included are: petroleum refiners, motor gasoline blenders, operators of natural gas processing plants and fractionators, inter-PAD transporters, importers, and major inventory holders of petroleum products and crude oil. When aggregated, the data reported by these sectors approximately represent the consumption of petroleum products in the United States. Data presented in the PSM are divided into two sections: Summary Statistics and Detailed Statistics.
Date:
August 25, 1995
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
The excretion of hexavalent uranium following intravenous administration. II, Studies on human subjects
Tracer studies employing uranium enriched in the isotopes U{sup 234}, U{sup 235} have been carried out in six human subjects; four males and two females. The uranium, 6 micrograms to 70 micrograms per kilogram of body weight was given intravenously in the hexavalent state as uranyl nitrate. Each individual of the series received a single injection of the metal except for one who was given two widely spaced doses. The first of these was when his condition was normal and the second after an acidosis had been produced by ingestion of ammonium chloride. Renal function tests including urinary catalase, protein, amino N to Creatinine N ratio and clearances of mannitol and p-aminohippurate were done before and after administration of uranium. Only at the 70 microgram per kilogram level in Subject 6 was there a slight rise in urinary catalase and protein suggesting that tolerance had been reached. The excretion of uranium was mainly in the urine, where from 70 to 85% of the administered dose appeared in the first twenty-four hours. Urine of the second twenty-four hours contained about 4% and the third twenty-four hour urine, 1.5% of the administered dose. Detectable amounts were excreted for at least two weeks.
Date:
June 25, 1948
Creator:
Bassett, S.H.; Frankel, A.; Cedars, N.; VanAlstine, H.; Waterhouse, C. & Cusson, K.
Object Type:
Report
System:
The UNT Digital Library
Hard Exclusive and Processes in QCD
Exclusive and semi-exclusive processes, the diffractive dissociation of hadrons into jets, and hard diffractive processes such as vector meson leptoproduction provide new testing grounds for QCD and essential information on the structure of light-cone wavefunctions of hadrons, particularly the pion distribution amplitude. I review the basic features of the leading-twist QCD predictions and the problems and challenges of studying QCD at the amplitude level. The application of the light-cone formalism to the exclusive semi-leptonic decay of heavy hadrons is also discussed.
Date:
August 25, 1999
Creator:
Brodsky, Stanley J.
Object Type:
Report
System:
The UNT Digital Library
Laser scattering detection and characterization of defects and machining damage in silicon nitride components.
It is known that surface and subsurface damage in machined silicon nitride (Si{sub 3}N{sub 4}) ceramic components can significantly affect component strength and lifetime. Because Si{sub 3}N{sub 4} may transmit some light into its subsurface, they have developed an elastic optical scattering technique to provide two-dimensional image data for detecting surface or subsurface defects and machining damage. This technique has been used to analyze diamond-ground Si{sub 3}N{sub 4} specimens subjected to various machining conditions. The results were compared with photomicroscopy data for detect characterization and were correlated with machining conditions.
Date:
November 25, 1998
Creator:
Sun, J. G.
Object Type:
Article
System:
The UNT Digital Library
New W mass results from CDF and D0
This article describes recent measurements of the W mass by the CDF and D0 Collabo-rations. CDF obtains a preliminary result of 80.473 ± 0.113 GeV for the W mass in the electron channel and D0 reports a preliminary result of 80.766 ± 0.234 GeV for electrons in the more forward (Endcap) rapidities. When combined with all previous measurements, the current average for the W mass measured at the Tevatron is 80.450 ± 0.063 GeV.
Date:
October 25, 1999
Creator:
Carithers, B.
Object Type:
Article
System:
The UNT Digital Library
E. Cartan moment of rotation in classical and quantum gravity. Final report
The geometric construction of the E. Cartan moment of rotation associated to the spacetime curvature provides a geometric interpretation of the gravitational field sources and describes geometrically how the sources are ``wired`` to the field in standard geometrodynamics. E. Cartan moment of rotation yields an alternate way (as opposed to using variational principles) to obtain Einstein equations. The E. Cartan construction uses in an essential way the soldering structure of the frame bundle underlying the geometry of the gravitational field of general relativity. The geometry of Ashtekar`s connection formulation of gravitation theory is based on a complex-valued self-dual connection that is defined not on the frame bundle of spacetime but, rather, on its complexification. We show how to transfer the construction of the E. Cartan moment of rotation to Ashtekar`s theory of gravity and demonstrate that no spurious equations are produced via this procedure.
Date:
May 25, 1994
Creator:
Kheyfets, A.
Object Type:
Report
System:
The UNT Digital Library
New public information resources on salt caverns.
For the past decade, interest has been growing in using underground salt caverns for disposing of wastes. The Railroad Commission of Texas has permitted a few caverns for disposal of nonhazardous oil field waste (NOW) and one cavern for disposal of naturally occurring radioactive materials (NORM) from oil field activities. Several salt caverns in Canada have also been permitted for disposal of NOW. In addition, oil and gas agencies in Louisiana and New Mexico are developing cavern disposal regulations. The US Department of Energy (DOE) has funded several studies to evaluate the technical feasibility, legality, economic viability, and risk of disposing of NOW and NORM in caverns. The results of these studies have been disseminated to the scientific and regulatory communities. However, as use of caverns for waste disposal increases, more government and industry representatives and members of the public will become aware of this practice and will need adequate information about how disposal caverns operate and the risks they pose. In anticipation of this need, DOE has fi.mded Argonne National Laboratory to develop a salt cavern public outreach program. Key components of this program are an informational brochure designed for nontechnical persons and a website that provides greater detail …
Date:
August 25, 1999
Creator:
Tomasko, D. & Veil, J. A.
Object Type:
Article
System:
The UNT Digital Library
PNC in hydrogen. different prospects using heliumlike ions.
The motivation for parity experiments in simple atomic systems is that the atomic physics is known precisely so they directly test the weak interactions. We review the status of the parity experiments that have been done in atomic hydrogen and suggest some possibilities for experiments in helium like ions.
Date:
September 25, 1998
Creator:
Dunford, R. W.
Object Type:
Article
System:
The UNT Digital Library
Development of beam position monitors for heavy ion recirculators
Work is underway at the Lawrence Livermore National Laboratory to design and build a small-scale, heavy ion recirculating induction accelerator. An essential part of this design work is the development of small nonintercepting diagnostics to measure beam current and position. This paper describes some of this work, with particular emphasis on the development of a small capacitive probe beam position monitor to resolve beam position to the 100 {mu}m level in a 6 cm diameter beam pipe. Initial measured results with an 80 keV potassium ion beam are presented.
Date:
April 25, 1995
Creator:
Deadrick, F. J.; Barnard, J. J.; Fessenden, T. J.; Meridith, J. W. & Rintamaki, J.
Object Type:
Article
System:
The UNT Digital Library
Radiation Effects on Materials in the Near-Field of a Nuclear waste Repository. 1997 annual progress report
'Sheet silicates (e.g. micas and clays) are important constituents of a wide variety of geological formations such as granite, basalt, and sandstone. Sheet silicates, particularly clays such as bentonite are common materials in near-field engineered barriers in high-level nuclear waste (HLW) repositories. This is because migration of radionuclides from an underground HLW repository to the geosphere may be significantly reduced by sorption of radionuclides (e.g., Pu, U and Np) onto sheet silicates (e.g., clays and micas) that line the fractures and pores of the rocks along groundwater flowpaths. In addition to surface sorption, it has been suggested that some sheet silicates may also be able to incorporate many radionuclides, such as Cs and Sr, in the inter-layer sites of the sheet structure. However, theability of the sheet silicates to incorporate radionuclides and retard release and migration of radionuclides may be significantly affected by the near-field radiation due to the decay of fission products and actinides. for example, the unique properties of the sheet structures will be lost completely if the structure becomes amorphous due to irradiation effects. Thus, the study of irradiation effects on sheet-structures, such as structural damage and modification of chemical properties, are critical to the performance assessment …
Date:
November 25, 1997
Creator:
Wang, L. M. & Ewing, R. C.
Object Type:
Report
System:
The UNT Digital Library
Imprinting artificial magnetic structures.
Recently we created La/Fe multilayers with a helical magnetic structure imprinted from the conditions of growth rather than by the magnetic interactions between layers. Each sublayer was 30{angstrom} thick, and during deposition the sample was rotated in an external field of 3 Oe. a field strong enough to magnetize the Fe layer being deposited but not sufficient to perturb the magnetization of the Fe layers already grown. As a result adjacent Fe layers formed a helical structure with a chirality and periodicity determined by the rotational direction and speed of the substrate and the rate of deposition. Following this discovery, an extensive set of experiments (mainly using Kerr effect magnetometry and polarized neutron reflectivity) was undertaken to ascertain the stability of imprinted magnetic structures, and to understand the onset of magnetization during growth. La/Fe imprinted helical magnetic structures (of different La and Fe thicknesses) were found to be stable in time and to be permanently erased only by magnetic fields larger than 90 Oe.
Date:
September 25, 1998
Creator:
Lohstroh, W.
Object Type:
Article
System:
The UNT Digital Library
A sodium guide star laser system for the Lick Observatory 3 meter telescope
The design, installation and performance data of a 20 W pulsed laser system for the 3 meter Shane telescope at the Lick Observatory is presented.
Date:
May 25, 1995
Creator:
Friedman, H. W.; Erbert, G. V.; Gavel, D. T.; Kuklo, T. C.; Malik, J. G.; Salmon, J. T. et al.
Object Type:
Article
System:
The UNT Digital Library
Proton driver study at Fermilab
Fermilab has started the design work of a high intensity proton source called the proton driver. It would provide a 4 MW proton beam to the target for muon production. This paper discusses the basic features of this machine and the associated accelerator physics and design issues.
Date:
October 25, 1999
Creator:
Chou, Weiren
Object Type:
Article
System:
The UNT Digital Library
FPIX1: An advanced pixel readout chip
At Fermilab, a pixel detector for BTeV is proposed for installation a few millimeters from the beam. Its information will be used in on-line track finding for the lowest level trigger system. This requires a high-speed readout and immediate data transfer from the pixel chip to the trigger processor. It is also believed that a 2-4 bits of analog information is required to achieve the targeted spatial resolution [1] with 50{micro} wide pixels. Our first prototype, FPIX0 [2], is now being used in a beam test to confirm physics simulations and to determine the required resolution of the analog ''information''. Our 2nd prototype, FPIX1, is a 160X18 pixel readout chip compatible with the ATLAS family of detectors. We have build and tested 4 FPIX1-detector assemblies. FPIX1 is realized in the HP 0.5{micro} process. The main features of FPIX1 are: 2bit flash ADC on each cell for maximum speed; Triggered or stand alone operation; and High speed sparse and time ordered Readout.
Date:
October 25, 1999
Creator:
al., A. Mekkaoui et
Object Type:
Article
System:
The UNT Digital Library
Approximate Near-Field Blast Theory: A Generalized Approach
A method for analyzing strong shock waves in arbitrary one-dimensional geometry is presented. An approximation to classical Taylor-Sedov theory is extended to the near-field case where source mass is not negligible, accounting for differences in the chemical properties of the source mass and ambient medium. Results from example calculations are compared with previously published analytical formulae.
Date:
October 25, 1999
Creator:
Hutchens, G.J.
Object Type:
Article
System:
The UNT Digital Library
Magnetic spiral structures in La/Fe multilayers.
The magnetic properties of La/Fe multilayers were tested by magneto-optical Kerr effect and polarized neutron reflectometry. The experiments indicated that above a layer thickness t{sub la} = 25{angstrom} the magnetic state of the virgin sample is represented by a spiral-like arrangement of magnetizations of subsequent Fe layers, whereas each Fe layer itself is ferromagnetic. Polarized neutron reflectometry shows that the helix has predominantly one chirality over the entire surface area of several cm{sup 2}. Tine magnetic spiral structure is imprinted during the growth process by rotating the sample in a small residual magnetic field. External magnetic field of 90 Oe are sufficient to erase the magnetic structure irreversibly.
Date:
September 25, 1998
Creator:
Lohstroh, W.
Object Type:
Article
System:
The UNT Digital Library
First results of the Fermilab high-brightness RF photoinjector
A collaboration has been formed between FNAL, UCLA, INFN Milano, the University of Rochester, and DESY to develop the technology of an RF photoinjector, followed by a superconducting cavity, to produce high bunch charge (8 nC) with low normalized emittance (< 20 mm {center_dot} mrad) in trains of 800 bunches separated by 1{micro}s. The activities of the collaboration fall into two categories: (1) the development of Injector II for the TeSLA/TTF accelerator [1]. This photoinjector (TTF RF Gun)was tested at Fermilab in September and October 1998 and installed at DESY in November 1998; (2) the installation at the A0 Hall of Fermilab of a modified version of the TTF photoinjector, for photoinjector R&D and to study novel applications of high-brightness, pulsed electrons beams. This photoinjector (A0 RF Gun) produced its first beam in March 1999. This paper presents a summary of the tests done at Fermilab on the TTF Injector II and the first results obtained on the new Fermilab photoinjector.
Date:
October 25, 1999
Creator:
Carneiro, Jean-Paul
Object Type:
Article
System:
The UNT Digital Library
Multilayer coated optics for an alpha-class extreme ultraviolet lithography system
We present the results of coating the first set of optical elements for an alpha-class extreme-ultraviolet (EUV) lithography system, the Engineering Test Stand (ETS). The optics were coated with Mo/Si multilayer mirrors using an upgraded DC-magnetron sputtering system. Characterization of the near-normal incidence EUV reflectance was performed using synchrotron radiation from the Advanced Light Source at the Lawrence Berkeley National Laboratory. Stringent requirements were met for these multilayer coatings in terms of reflectance, wavelength matching among the different optics, and thickness control across the diameter of each individual optic. Reflectances above 65% were achieved at 13.35 nm at near-normal angles of incidence. The run-to-run reproducibility of the reflectance peak wavelength was maintained to within 0.4%, providing the required wavelength matching among the seven multilayer-coated optics. The thickness uniformity (or gradient) was controlled to within {+-}0.25% peak-to-valley (P-V) for the condenser optics and {+-}0.1% P-V for the four projection optics, exceeding the prescribed specification for the optics of the ETS.
Date:
August 25, 1999
Creator:
Folta, J. A.; Grabner, R. F.; Hudyma, R. M.; Montcalm, C.; Schmidt, M. A.; Spiller, E. et al.
Object Type:
Article
System:
The UNT Digital Library
Development of a video-based slurry sensor for on-line ash analysis. Technical progress report, third quarter, April 1, 1995--June 30, 1995
Automatic control of fine coal cleaning circuits has traditionally been limited by the lack of sensors for on-line ash analysis. Although several nuclear-based analyzers are available, none have seen widespread acceptance. This is largely due to the fact that nuclear sensors are expensive and tend to be influenced by changes in seam type and pyrite content Recently, researchers at VPI&SU have developed an optical sensor for phosphate analysis. The sensor uses image processing technology to analyze video images of phosphate ore. It is currently being used by Texas gulf for off-line analysis of dry flotation concentrates. The primary advantages of optical sensors over nuclear sensors are that they are significantly cheaper, are not subject to measurement variations due to changes in high atomic number minerals, are inherently safer and require no special radiation permitting. The purpose of this work is to apply the knowledge gained in the development of an optical phosphate analyzer to the development of an on-line ash analyzer for fine coal slurries. During the past quarter, a new prototype sample presentation system for the optical analyzer has been developed. This new approach appears to solve the problems encountered with previous prototypes. A qualitative comparison of the images …
Date:
July 25, 1995
Creator:
Adel, G. T. & Luttrell, G. H.
Object Type:
Report
System:
The UNT Digital Library
Measurements of deep heating generated by ultra-intense laser-plasma interactions
We measure 300 eV thermal temperatures at near-solid densities by x-ray spectroscopy of tracer layers buried up to 30 pm inside CH slabs which are irradiated by a 0.5 kJ, 5 ps laser. X-ray imaging data suggest that collimated electron transport produces comparable temperatures as deep as 200 pm, and unexpectedly show the heated regions to be 50-120 pm-diameter rings. The data indicate that intense lasers can directionally heat solid matter to high temperatures over large distances; the results are relevant for fast-ignition inertial-confinement fusion and hot, dense plasma research
Date:
August 25, 1999
Creator:
Hatchett, S. P.; Key, M. H.; Koch, J. A.; Lee, R. W.; Pennington, D.; Stephens, R. B. et al.
Object Type:
Article
System:
The UNT Digital Library
Metrological Challenges of Synchrotron Radiation Optics
Modern third generation storage rings, require state-of-the-art grazing incidence x-ray optics, in order to monochromate the Synchrotrons Radiation (SR) source photons, and focus them into the experimental stations. Slope error tolerances in the order of 0.5 {micro}Rad RMS, and surface roughness well below 5 {angstrom} RMS, are frequently specified for mirrors and gratings exceeding 300 mm in length. Non-contact scanning instruments were developed, in order to characterize SR optical surfaces, of spherical and aspherical shape. Among these, the Long Trace Profiler (LTP), a double pencil slope measuring interferometer, has proved to be particularly reliable, and was adopted by several SR optics metrology laboratories. The ELETTRA soft x-rays and optics metrology laboratory, has operated an LTP since 1992. We review the basic operating principles of this instrument, and some major instrumental and environmental improvements, that were developed in order to detect slope errors lower than 1 {micro}Rad RMS on optical surfaces up to one metre in length. A comparison among measurements made on the same reference flat, by different interferometers (most of them were LTPs) can give some helpful indications in order to optimize the quality of measurement.
Date:
May 25, 1999
Creator:
Sostero, G.
Object Type:
Article
System:
The UNT Digital Library
High-spin states in {sup 71}As, {sup 72}Se, and {sup 72}Br.
The {sup 16}O + {sup 58}Ni reaction was used to study yrast and non-yrast excitations in {sup 71}As, {sup 72}Se, and {sup 72}Br. High-spin yrast and negative-parity non-yrast bands were observed in {sup 72}Se. The F{sub 7/2} proton extruder orbital was identified in {sup 71}As. The odd-even staggering in the {pi}g{sub 9/2}{nu}g{sub 9/2} decoupled band in {sup 72}Br is compared with similar structures in heavier Br isotopes.
Date:
August 25, 1998
Creator:
Fotiades, N.
Object Type:
Article
System:
The UNT Digital Library