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Corrective Action Investigation Plan for Corrective Action Unit 321: Area 22 Weather Station Fuel Storage, Nevada Test Site, Nevada, Revision 0. UPDATED WITH RECORD OF TECHNICAL CHANGE No.1
This Corrective Action Investigation Plan (CAIP) has been developed in accordance with the Federal Facility Agreement and Consent Order (FFACO) that was agreed to by the US Department of Energy, Nevada Operations Office (DOE/NV); the State of Nevada Division of Environmental Protection (NDEP); and the US Department of Defense (FFACO, 1996). The CAIP is a document that provides or references all of the specific information for investigation activities associated with Corrective Action Units (CAUs) or Corrective Action Sites (CASs). According to the FFACO (1996), CASs are sites potentially requiring corrective action(s) and may include solid waste management units or individual disposal or release sites. A CAU consists of one or more CASs grouped together based on geography, technical similarity, or agency responsibility for the purpose of determining corrective actions. This CAIP contains the environmental sample collection objectives and the criteria for conducting site investigation activities at the CAU 321 Area 22 Weather Station Fuel Storage, CAS 22-99-05 Fuel Storage Area. For purposes of this discussion, this site will be referred to as either CAU 321 or the Fuel Storage Area. The Fuel Storage Area is located in Area 22 of the Nevada Test Site (NTS). The NTS is approximately 105 …
Date:
February 8, 1999
Creator:
/NV, U.S. DOE
Object Type:
Report
System:
The UNT Digital Library
On possible use of bent crystal to improve Tevatron beam scraping
A possibility to improve the Tevatron beam halo scraping using a bent channeling crystal instead of a thin scattering primary collimator is studied. To evaluate the efficiency of the system, realistic simulations have been performed using the CATCH and STRUCT Monte Carlo codes. It is shown that the scraping efficiency can be increased and the accelerator-related backgrounds in the CDF and DØ collider detectors can be reduced by about one order of magnitude. Results on scraping efficiency versus thickness of amorphous layer of the crystal, crystal alignment and its length are presented.
Date:
April 8, 1999
Creator:
A.I. Drozhdin, N.V. Mokhov and V.M. Biryukov
Object Type:
Article
System:
The UNT Digital Library
Phase stability of laves intermetallics in stainless steel-zirconium alloys.
Phase transformations occurring in a stainless steel-15 wt% zirconium (SS-15Zr) alloy were studied by in situ neutron diffraction. Neutron diffraction patterns as a function of time were obtained on alloys that were held at various elevated temperatures (1084-1275 C). As-cast SS-15Zr alloys contain ferrite, austenite, ZrFe{sub 2}-type Laves polytypes C36 and C15, and small amounts of a Fe{sub 23}Zr{sub 6}-type intermetallic. Annealing at high temperatures resulted in an increase of the Fe{sub 23}Zr{sub 6}, intermetallic content. The C15 Laves polytype is the equilibrium phase for T {le} 1230 C; C36 is the stable polytype at higher temperatures ({approximately}1275 C). Phase changes were slow for temperatures <1100 C.These findings have important implications for use of the SS-15Zr alloy as a nuclear waste form.
Date:
April 8, 1999
Creator:
Abraham, D. P.
Object Type:
Article
System:
The UNT Digital Library
Orientation imaging microscopy investigation of the compression deformation of a [011] ta single crystal
High-purity tantalum single crystal cylinders oriented with [110] parallel to the cylinder axis were deformed 10, 20, and 30 percent in compression. The samples were subsequently sectioned for characterization using Orientation Imaging Microscopy (O&I) along two orthogonal sectioning planes: one in the plane containing [001] and [110] (longitudinal) and the other in the plane containing [1{anti 1}0] and[110] (transverse). To examine local lattice rotations, the Euler angles relative to a reference angle at the section center were decomposed to their in-plane and out-of-plane components. The in-plane and out-of-plane misorientation maps for all compression tests reveal inhomogeneous deformation everywhere and particularly large lattice rotations in the comers of the longitudinal section. Of particular interest are the observed alternating orientation changes. This suggests the existence of networks of dislocations with net alternating sign that are required to accommodate the observed rotations. Rotation maps from the transverse section are distinctly different in appearance from those in the longitudinal plane. However, the rotation maps confirm that the rotations observed above were about the [1{anti 1}0] axis. Alternating orientation changes are also observed on this section. Results will be directly compared with crystal rotations predicted using finite element methods and reviewed in light of the …
Date:
January 8, 1999
Creator:
Adams, B L; Campbell, G H; King, W E; Lassila, D H; Stolken, J S; Sun, S et al.
Object Type:
Report
System:
The UNT Digital Library
Detecting data and schema changes in scientific documents
Data stored in a data warehouse must be kept consistent and up-to-date with the underlying information sources. By providing the capability to identify, categorize and detect changes in these sources, only the modified data needs to be transferred and entered into the warehouse. Another alternative, periodically reloading from scratch, is obviously inefficient. When the schema of an information source changes, all components that interact with, or make use of, data originating from that source must be updated to conform to the new schema. In this paper, the authors present an approach to detecting data and schema changes in scientific documents. Scientific data is of particular interest because it is normally stored as semi-structured documents, and it incurs frequent schema updates. They address the change detection problem by detecting data and schema changes between two versions of the same semi-structured document. This paper presents a graph representation of semi-structured documents and their schema before describing their approach to detecting changes while parsing the document. It also discusses how analysis of a collection of schema changes obtained from comparing several individual can be used to detect complex schema changes.
Date:
June 8, 1999
Creator:
Adiwijaya, I; Critchlow, T & Musick, R
Object Type:
Article
System:
The UNT Digital Library
Ensemble: 1999-11-08 - Les Petits Violons
Concert presented at the UNT College of Music Recital Hall.
Date:
November 8, 1999
Creator:
Adkins, Cecil
Object Type:
Sound
System:
The UNT Digital Library
Heat Pipe Solar Receiver Development Activities at Sandia National Laboratories
Over the past decade, Sandia National Laboratories has been involved in the development of receivers to transfer energy from the focus of a parabolic dish concentrator to the heater tubes of a Stirling engine. Through the isothermal evaporation and condensation of sodium. a heat-pipe receiver can efficiently transfer energy to an engine's working fluid and compensate for irregularities in the flux distribution that is delivered by the concentrator. The operation of the heat pipe is completely passive because the liquid sodium is distributed over the solar-heated surface by capillary pumping provided by a wick structure. Tests have shown that using a heat pipe can boost the system performance by twenty percent when compared to directly illuminating the engine heater tubes. Designing heat pipe solar receivers has presented several challenges. The relatively large area ({approximately}0.2 m{sup 2}) of the receiver surface makes it difficult to design a wick that can continuously provide liquid sodium to all regions of the heated surface. Selecting a wick structure with smaller pores will improve capillary pumping capabilities of the wick, but the small pores will restrict the flow of liquid and generate high pressure drops. Selecting a wick that is comprised of very tine filaments …
Date:
January 8, 1999
Creator:
Adkins, D. R.; Andraka, C. E.; Moreno, J. B.; Moss, T. A.; Rawlinson, K. S. & Showalter, S. K.
Object Type:
Article
System:
The UNT Digital Library
Texture Development During Equal Channel Angular Forging of BCC Metals
Equal channel angular forging (ECAF) has been proposed as a severe plastic deformation technique for processing metals, alloys, and composites [e.g. Segal, 1995] (Fig. 1). The technique offers two capabilities of practical interest: a high degree of strain can be introduced with no change in the cross-sectional dimensions of the work-piece, hence, even greater strains can be introduced by re-inserting the work-piece for further deformation during subsequent passes through the ECAF die. Additionally, the deformation is accomplished by simple shear (like torsion of a short tube) on a plane whose orientation, with respect to prior deformations, can be controlled by varying the processing route. There is a nomenclature that has developed in the literature for the typical processing routes: A: no rotations; B{sub A}: 90 degrees CW (clockwise), 90 degrees CCW (counterclockwise), 9O degrees CW, 90 degrees CCW...; Bc: 90 degrees CW, 90 degrees CW, 90 degrees CW...; and C: 180 degrees, 18 0 degrees.... The impact of processing route on the subsequent microstructure [Ferasse, Segal, Hartwig and Goforth, 1997; Iwahashi, Horita, Nemoto and Langdon, 1996] and texture [Gibbs, Hartwig, Cornwell, Goforth and Payzant, 1998] has been the subject of numerous experimental studies.
Date:
August 8, 1999
Creator:
Agnew, S. R.
Object Type:
Article
System:
The UNT Digital Library
Gas-to-liquids synthetic fuels for use in fuel cells : reformability, energy density, and infrastructure compatibility.
The fuel cell has many potential applications, from power sources for electric hybrid vehicles to small power plants for commercial buildings. The choice of fuel will be critical to the pace of its commercialization. This paper reviews the various liquid fuels being considered as an alternative to direct hydrogen gas for the fuel cell application, presents calculations of the hydrogen and carbon dioxide yields from autothermal reforming of candidate liquid fuels, and reports the product gas composition measured from the autothermal reforming of a synthetic fuel in a micro-reactor. The hydrogen yield for a synthetic paraffin fuel produced by a cobalt-based Fischer-Tropsch process was found to be similar to that of retail gasoline. The advantages of the synthetic fuel are that it contains no contaminants that would poison the fuel cell catalyst, is relatively benign to the environment, and could be transported in the existing fuel distribution system.
Date:
September 8, 1999
Creator:
Ahmed, S.; Kopasz, J. P.; Russell, B. J. & Tomlinson, H. L.
Object Type:
Article
System:
The UNT Digital Library
A Silicon, Carbon and Deuterium NMR Investigation of Molecular Templating in Amorphous Silicas
The precise pore sizes defined by crystalline zeolite lattices have led to intensive research on zeolite membranes. Unfortunately zeolites have proven to be extremely difficult to prepare in a defect-free thin film form needed for membrane flux and selectivity. We introduce tetrapropylammonium TPA (a structure directing agent for zeolite ZSM-5) into a silica sol and exploit the development of high solvation stresses to create templated amorphous silicas with pore apertures comparable in size to those of ZSM-5. {sup 29}Si and {sup 2}H NMR experiments were performed to evaluate the efficacy of our templating approach. The {sup 29}Si NMR spectrum of the silica matrix was observed by an intermolecular cross-polarization experiment between the {sup 1}H nuclei of TPA and the {sup 29}Si nuclei in the silica matrix. The efficiency of the cross-polarization interaction was used to investigate the degree to which the matrix formed a tight cage surrounding the template molecule. Normally prepared xerogel materials exhibited only weak interactions between the two sets of nuclei. Drying under reduced pressure, where solvation stresses are maximized, resulted in significantly increased interactions. Analogous materials were prepared using fully deuterated TPA. The {sup 2}H NMR wideline spectra consisted of a partially narrowed resonance, corresponding to …
Date:
April 8, 1999
Creator:
Alam, T. M.; Assink, R. A.; Brinker, C. J.; Click, C. A. & Naik, S. J.
Object Type:
Article
System:
The UNT Digital Library
(6)Li, (7)Li Nuclear Magnetic Resonance Investigation of Lithium Coordination in Binary Phosphate Glasses
{sup 6}Li and {sup 7}Li solid state magic angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy has been used to investigate the local coordination environment of lithium in a series of xLi{sub 2}O {center_dot} (1-x)P{sub 2}O{sub 5} glasses, where 0.05 {le} x {le} 0.55. Both the {sup 6}Li and {sup 7}Li show chemical shift variations with changes in the Li{sub 2}O concentration, but the observed {sup 6}Li NMR chemical shifts closely approximate the true isotropic chemical shift and can provide a measure of the lithium bonding environment. The {sup 6}Li NMR results indicate that in this series of lithium phosphate glasses the Li atoms have an average coordination between four and five. The results for the metaphosphate glass agree with the coordination number and range of chemical shifts observed for crystalline LiPO{sub 3}. An increase in the {sup 6}Li NMR chemical shift with increasing Li{sub 2}O content was observed for the entire concentration range investigated, correlating with increased cross-linking of the phosphate tetrahedral network by O-Li-O bridges. The {sup 6}Li chemical shifts were also observed to vary monotonically through the anomalous glass transition temperature (T{sub g}) minimum. This continuous chemical shift variation shows that abrupt changes in the Li coordination …
Date:
February 8, 1999
Creator:
Alam, T.M.; Boyle, T.J.; Brow, R.K. & Conzone, S.
Object Type:
Article
System:
The UNT Digital Library
The Oklahoma Daily (Norman, Okla.), Vol. 83, No. 80, Ed. 1 Friday, January 8, 1999
Student newspaper of the University of Oklahoma in Norman, Oklahoma that includes national, local, and campus news along with advertising.
Date:
January 8, 1999
Creator:
Allam, Heather
Object Type:
Newspaper
System:
The Gateway to Oklahoma History
The Oklahoma Daily (Norman, Okla.), Vol. 83, No. 100, Ed. 1 Monday, February 8, 1999
Student newspaper of the University of Oklahoma in Norman, Oklahoma that includes national, local, and campus news along with advertising.
Date:
February 8, 1999
Creator:
Allam, Heather
Object Type:
Newspaper
System:
The Gateway to Oklahoma History
The Oklahoma Daily (Norman, Okla.), Vol. 83, No. 120, Ed. 1 Monday, March 8, 1999
Student newspaper of the University of Oklahoma in Norman, Oklahoma that includes national, local, and campus news along with advertising.
Date:
March 8, 1999
Creator:
Allam, Heather
Object Type:
Newspaper
System:
The Gateway to Oklahoma History
The Oklahoma Daily (Norman, Okla.), Vol. 83, No. 136, Ed. 1 Thursday, April 8, 1999
Student newspaper of the University of Oklahoma in Norman, Oklahoma that includes national, local, and campus news along with advertising.
Date:
April 8, 1999
Creator:
Allam, Heather
Object Type:
Newspaper
System:
The Gateway to Oklahoma History
Simulation of damage evolution and accumulation in vanadium
Energetic atoms which have been knocked off their lattice sites by neutron or ion irradiation leave a trail of vacancies and interstitials in their wake. Most of these defects recombine with their opposites within their own collision cascade. Some fraction, however, escape to become freely migrating defects (FMD) in the bulk of the material. The interaction of FMD with the microstructure has long been linked to changes in the macroscopic properties of materials under irradiation. We calculate the fraction of FMD in pure vanadium for a wide range of temperatures and primary knock-on atom (PKA) energies. The collision cascade database is obtained from molecular dynamics (MD) simulations with an embedded atom method (EAM) potential. The actual FMD calculation is carried out by a kinetic Monte Carlo (kMC) code with a set of parameters extracted either from the experimental literature or from MD simulations. We take two different approaches to the problem and compare them. The first consists of an idealized simulation for single cascades. Annealing each cascade at different temperatures allows the mobile species to escape and account for FMD. The second analyzes bulk diffusion and damage.
Date:
February 8, 1999
Creator:
Alonso, E; Caturla, M J; Diaz De La Rubia, T & Perlado, M J
Object Type:
Report
System:
The UNT Digital Library
Nitrogen Implantation Effects on the Chemical Bonding and Hardness of Boron and Boron Nitride Coatings
Boron nitride (BN) coatings are deposited by the reactive sputtering of fully dense, boron (B) targets utilizing an argon-nitrogen (Ar-N{sub 2}) reactive gas mixture. Near-edge x-ray absorption fine structure analysis reveals features of chemical bonding in the B 1s photoabsorption spectrum. Hardness is measured at the film surface using nanoindentation. The BN coatings prepared at low, sputter gas pressure with substrate heating are found to have bonding characteristic of a defected hexagonal phase. The coatings are subjected to post-deposition nitrogen (N{sup +} and N{sub 2}{sup +}) implantation at different energies and current densities. The changes in film hardness attributed to the implantation can be correlated to changes observed in the B 1s NEXAFS spectra.
Date:
February 8, 1999
Creator:
Anders, S.; Felter, T.; Hayes, J.; Jankowski, Alan Frederic; Patterson, R.; Poker, D. et al.
Object Type:
Article
System:
The UNT Digital Library
Development and Design of a User Interface for a Computer Automated Heating, Ventilation, and Air Conditioning System
A user interface is created to monitor and operate the heating, ventilation, and air conditioning system. The interface is networked to the system's programmable logic controller. The controller maintains automated control of the system. The user through the interface is able to see the status of the system and override or adjust the automatic control features. The interface is programmed to show digital readouts of system equipment as well as visual queues of system operational statuses. It also provides information for system design and component interaction. The interface is made easier to read by simple designs, color coordination, and graphics. Fermi National Accelerator Laboratory (Fermi lab) conducts high energy particle physics research. Part of this research involves collision experiments with protons, and anti-protons. These interactions are contained within one of two massive detectors along Fermilab's largest particle accelerator the Tevatron. The D-Zero Assembly Building houses one of these detectors. At this time detector systems are being upgraded for a second experiment run, titled Run II. Unlike the previous run, systems at D-Zero must be computer automated so operators do not have to continually monitor and adjust these systems during the run. Human intervention should only be necessary for system start …
Date:
October 8, 1999
Creator:
Anderson, B.
Object Type:
Report
System:
The UNT Digital Library
Progress and future plans for MPC and A at Chelyabinsk-70
This paper describes that portion of the Nuclear Materials Protection, Control, and Accounting (MPC and A) program that is directed specifically to the needs of the All Russian Scientific Research Institute of Technical Physics (VNIITF), also called Chelyabinsk-70. Chelyabinsk-70 is located in the Ural Mountains, approximately 2000 km east of Moscow and 100 km south of Ekaterinburg. The MPC and A work that has been completed, is underway and planned at the facility will be described. During the first two years of the VNIITF project, emphasis was on the Pulse Research Reactor Facility (PRR), which contains one metal and two liquid pulse reactors and associated nuclear material storage rooms and a control center. A commissioning of the PRR was held in May of 1998. With the completion of the MPC and A work in the PRR, new physical protection work is focusing on other areas. VNIITF-wide physical protection initiatives underway include access control and computerized badging systems, and a central MPC and A control system. Measured physical inventory taking is a high priority for the VNIITF Project Team. A VNIITF-wide computerized accounting system is also being developed for the large and diverse inventory of nuclear material subject to MPC and …
Date:
July 8, 1999
Creator:
Apt, K.; Blasy, J.; Bukin, D.; Cahalane, P.; Churikov, Y.; Curtis, D. et al.
Object Type:
Article
System:
The UNT Digital Library
Productivity and Injectivity of Horizontal Wells
This quarterly report is based on the last activity above. It gives a brief account of the work and the complete study will be included in the next Annual Report of the project.
Date:
November 8, 1999
Creator:
Arababi, Sepehr; Aziz, Khalid; Hayashida, Yasuyuki & Hewett, Thomas
Object Type:
Report
System:
The UNT Digital Library
Productivity and Injectivity of Horizontal Wells
The work on modeling hydraulically fractured horizontal wells has moved forward. A literature review on the subject was done and some of the existing models have been coded and applied to example problems for evaluation purposes. Previous work on the elects of heterogeneities on the performance of horizontal wells was continued by conducting a sensitivity study on various parameters that were kept constant in the earlier study. For example, we have studied the elect of gas cap and aquifer size, well location, fluid viscosity, etc. The experimental work on using horizontal wells as injectors and producers in a gas injection gravity drainage process continued. New and repeat experiments were conducted. Work on streamline grids was advanced by considering example problems with highly distorted grids which cannot be directly used for flow simulation. Grid smoothing and domain mapping techniques were investigated to handle such situations. A technique was developed for the computation o f well index with consideration to wellbore pressure drop. A recently developed reservoir/wellbore coupling model was used for this purpose.
Date:
November 8, 1999
Creator:
Arbabi, Sepehr; Aziz, Khalid; Hewett, Thomas A. & Smith, Marilyn
Object Type:
Report
System:
The UNT Digital Library
WildCare Foundation's Wildlife Rehabilitation Center
Photograph of a Red Tail Hawk at the WildCare Foundation's Wildlife Rehabilitation Center.
Date:
March 8, 1999
Creator:
Argo, Jim
Object Type:
Photograph
System:
The Gateway to Oklahoma History
WildCare Foundation's Wildlife Rehabilitation Center
Photograph of a Red Tail Hawk at the WildCare Foundation's Wildlife Rehabilitation Center.
Date:
March 8, 1999
Creator:
Argo, Jim
Object Type:
Photograph
System:
The Gateway to Oklahoma History
WildCare Foundation's Wildlife Rehabilitation Center
Photograph of a Barred Owl at the WildCare Foundation's Wildlife Rehabilitation Center.
Date:
March 8, 1999
Creator:
Argo, Jim
Object Type:
Photograph
System:
The Gateway to Oklahoma History