Computer control raises welding from art to science: Inventions & Innovations success story (open access)

Computer control raises welding from art to science: Inventions & Innovations success story

Fact sheet written for the Inventions and Innovation Program about a new welding control system that provides precise, effective welds and documents weld integrity.
Date: February 1, 2000
Creator: unknown
Object Type: Book
System: The UNT Digital Library
A CONCEPTUAL AND CALCULATION MODEL FOR GAS FORMATION FROM IMPURE CALCINED PLUTONIUM OXIDES (open access)

A CONCEPTUAL AND CALCULATION MODEL FOR GAS FORMATION FROM IMPURE CALCINED PLUTONIUM OXIDES

None
Date: February 1, 2000
Creator: Lyman, J. & Eller, P.
Object Type: Article
System: The UNT Digital Library
Conceptual Design of a Magnet System to Generate 20T in a 0.15m Diameter Bore, Employing an Inductor Precooled by Liquid Nitrogen, 1999, December (open access)

Conceptual Design of a Magnet System to Generate 20T in a 0.15m Diameter Bore, Employing an Inductor Precooled by Liquid Nitrogen, 1999, December

None
Date: February 20, 2000
Creator: Potrepka, D. M.
Object Type: Article
System: The UNT Digital Library
Conductor development for High Energy Physics - Plans and Status of the U.S. Program (open access)

Conductor development for High Energy Physics - Plans and Status of the U.S. Program

None
Date: February 2, 2000
Creator: Scanlan, R. M.
Object Type: Article
System: The UNT Digital Library
A conservative control strategy for variable-speed stall-regulated wind turbines (open access)

A conservative control strategy for variable-speed stall-regulated wind turbines

Simulation models of a variable-speed, fixed-pitch wind turbine were investigated to evaluate the feasibility of constraining rotor speed and power output without the benefit of active aerodynamic control devices. A strategy was postulated to control rotational speed by specifying the demanded generator torque. By controlling rotor speed in relation to wind speed, the aerodynamic power extracted by the blades from the wind was manipulated. Specifically, the blades were caused to stall in high winds. In low and moderate winds, the demanded generator torque and the resulting rotor speed were controlled to cause the wind turbine to operate near maximum efficiency. Using the developed models, simulations were conducted of operation in turbulent winds. Results indicated that rotor speed and power output were well regulated. Preliminary investigations of system dynamics showed that, compared to fixed-speed operation, variable-speed operation caused cyclic loading amplitude to be reduced for the turbine blades and low-speed shaft and slightly increased for the tower loads. This result suggests a favorable impact on fatigue life from implementation of the proposed control strategy.
Date: February 8, 2000
Creator: Muljadi, E.; Pierce, K. & Migliore, P.
Object Type: Article
System: The UNT Digital Library
Constraints on the gluon density from lepton pair production (open access)

Constraints on the gluon density from lepton pair production

The hadroproduction of lepton pairs with mass Q and finite transverse momentum Q{sub T} is described in perturbative QCD by the same partonic subprocesses as prompt photon production. The authors demonstrate that, like prompt photon production, lepton pair production is dominated by quark-gluon scattering in the region Q{sub T} > Q/2. This feature leads to sensitivity to the gluon density in kinematical regimes accessible in collider and fixed target experiments, and it provides a new independent method for constraining the gluon density.
Date: February 4, 2000
Creator: Berger, E. L. & Klasen, M.
Object Type: Article
System: The UNT Digital Library
Contingency Planning for Feedstock Splits Between the Immobilization and MOX Disposition Routes to Fissile Materials Disposition (open access)

Contingency Planning for Feedstock Splits Between the Immobilization and MOX Disposition Routes to Fissile Materials Disposition

None
Date: February 11, 2000
Creator: Gray, L.W. & Edmunds, T.A.
Object Type: Article
System: The UNT Digital Library
Continuous casting/inside rolling of hollow rounds: Steel Project fact sheet (open access)

Continuous casting/inside rolling of hollow rounds: Steel Project fact sheet

Fact sheet written for the Inventions and Innovation Program about a new process for casting hollow steel rounds that saves energy and costs.
Date: February 1, 2000
Creator: National Renewable Energy Laboratory (U.S.)
Object Type: Book
System: The UNT Digital Library
Continuous-flow stirred-tank reactor 20-L demonstration test: Final report (open access)

Continuous-flow stirred-tank reactor 20-L demonstration test: Final report

One of the proposed methods of removing the cesium, strontium, and transuranics from the radioactive waste storage tanks at Savannah River is the small-tank tetraphenylborate (TPB) precipitation process. A two-reactor-in-series (15-L working volume each) continuous-flow stirred-tank reactor (CSTR) system was designed, constructed, and installed in a hot cell to test the Savannah River process. The system also includes two cross-flow filtration systems to concentrate and wash the slurry produced in the process, which contains the bulk of radioactivity from the supernatant processed through the system. Installation, operational readiness reviews, and system preparation and testing were completed. The first test using the filtration systems, two CSTRs, and the slurry concentration system was conducted over a 61-h period with design removal of Cs, Sr, and U achieved. With the successful completion of Test 1a, the following tests, 1b and 1c, were not required.
Date: February 1, 2000
Creator: Lee, D. D. & Collins, J. L.
Object Type: Report
System: The UNT Digital Library
Continuum mechanical and computational aspects of material behavior (open access)

Continuum mechanical and computational aspects of material behavior

The focus of the work is the application of continuum mechanics to materials science, specifically to the macroscopic characterization of material behavior at small length scales. The long-term goals are a continuum-mechanical framework for the study of materials that provides a basis for general theories and leads to boundary-value problems of physical relevance, and computational methods appropriate to these problems supplemented by physically meaningful regularizations to aid in their solution. Specific studies include the following: the development of a theory of polycrystalline plasticity that incorporates free energy associated with lattice mismatch between grains; the development of a theory of geometrically necessary dislocations within the context of finite-strain plasticity; the development of a gradient theory for single-crystal plasticity with geometrically necessary dislocations; simulations of dynamical fracture using a theory that allows for the kinking and branching of cracks; computation of segregation and compaction in flowing granular materials.
Date: February 10, 2000
Creator: Fried, Eliot & Gurtin, Morton E.
Object Type: Report
System: The UNT Digital Library
Control-matrix approach to stellarator design and control (open access)

Control-matrix approach to stellarator design and control

The full space Z always equal to {l{underscore}brace}Zj=1,..Nz{r{underscore}brace} of independent variables defining a stellarator configuration is large. To find attractive design points in this space, or to understand operational flexibility about a given design point, one needs insight into the topography in Z-space of the physics figures of merit Pi which characterize the machine performance, and means of determining those directions in Z-space which give one independent control over the Pi, as well as those which affect none of them, and so are available for design flexibility. The control matrix (CM) approach described here provides a mathematical means of obtaining these. In this work, the authors describe the CM approach and use it in studying some candidate Quasi-Axisymmetric (QA) stellarator configurations the NCSX design group has been considering. In the process of the analysis, a first exploration of the topography of the configuration space in the vicinity of these candidate systems has been performed, whose character is discussed.
Date: February 9, 2000
Creator: Mynick, H.E. & Pomphrey, N.
Object Type: Report
System: The UNT Digital Library
Coordinate Standard Measurement Development (open access)

Coordinate Standard Measurement Development

A Shelton Precision Interferometer Base, which is used for calibration of coordinate standards, was improved through hardware replacement, software geometry error correction, and reduction of vibration effects. Substantial increases in resolution and reliability, as well as reduction in sampling time, were achieved through hardware replacement; vibration effects were reduced substantially through modification of the machine component dampening and software routines; and the majority of the machine's geometry error was corrected through software geometry error correction. Because of these modifications, the uncertainty of coordinate standards calibrated on this device has been reduced dramatically.
Date: February 18, 2000
Creator: Hanshaw, R.A.
Object Type: Report
System: The UNT Digital Library
COPS: Large-scale nonlinearly constrained optimization problems (open access)

COPS: Large-scale nonlinearly constrained optimization problems

The authors have started the development of COPS, a collection of large-scale nonlinearly Constrained Optimization Problems. The primary purpose of this collection is to provide difficult test cases for optimization software. Problems in the current version of the collection come from fluid dynamics, population dynamics, optimal design, and optimal control. For each problem they provide a short description of the problem, notes on the formulation of the problem, and results of computational experiments with general optimization solvers. They currently have results for DONLP2, LANCELOT, MINOS, SNOPT, and LOQO.
Date: February 10, 2000
Creator: Bondarenko, A. S.; Bortz, D. M. & More, J. J.
Object Type: Report
System: The UNT Digital Library
Corrective Action Decision Document/Closure Report for Corrective Action Unit 266: Area 25 Building 3124 Leachfield, Nevada Test Site, Nevada (open access)

Corrective Action Decision Document/Closure Report for Corrective Action Unit 266: Area 25 Building 3124 Leachfield, Nevada Test Site, Nevada

This Corrective Action Decision Document/Closure Report (CADD/CR) was prepared for Corrective Action Unit (CAU) 266, Area 25 Building 3124 Leachfield, in accordance with the Federal Facility Agreement and Consent Order. Located in Area 25 at the Nevada Test Site in Nevada, CAU 266 includes Corrective Action Site (CAS) 25-05-09. The Corrective Action Decision Document and Closure Report were combined into one report because sample data collected during the corrective action investigation (CAI) indicated that contaminants of concern (COCs) were either not present in the soil, or present at concentrations not requiring corrective action. This CADD/CR identifies and rationalizes the U.S. Department of Energy, Nevada Operations Office's recommendation that no corrective action was necessary for CAU 266. From February through May 1999, CAI activities were performed as set forth in the related Corrective Action Investigation Plan. Analytes detected during the three-stage CAI of CAU 266 were evaluated against preliminary action levels (PALs) to determine COCs, and the analysis of the data generated from soil collection activities indicated the PALs were not exceeded for total volatile/semivolatile organic compounds, total petroleum hydrocarbons, polychlorinated biphenyls, total Resource Conservation and Recovery Act metals, gamma-emitting radionuclides, isotopic uranium/plutonium, and strontium-90 for any of the samples. However, …
Date: February 17, 2000
Creator: United States. National Nuclear Security Administration. Nevada Operations Office.
Object Type: Report
System: The UNT Digital Library
Corrective Action Decision Document/Closure Report for Corrective Action Unit 500: Test Cell A Septic System, Nevada Test Site, Nevada, Rev. 0 (open access)

Corrective Action Decision Document/Closure Report for Corrective Action Unit 500: Test Cell A Septic System, Nevada Test Site, Nevada, Rev. 0

This Corrective Action Decision Document/Closure Report (CADD/CR) has been prepared for Corrective Action Unit (CAU) 500: Test Cell A Septic System, in accordance with the Federal Facility Agreement and Consent Order. Located in Area 25 at the Nevada Test Site in Nevada, CAU 500 is comprised of one Corrective Action Site, CAS 25-04-05. This CADD/CR identifies and rationalizes the U.S. Department of Energy, Nevada Operations Office's (DOE/NV's) recommendation that no corrective action is deemed necessary for CAU 500. The Corrective Action Decision Document and Closure Report have been combined into one report based on sample data collected during the field investigation performed between February and May 1999, which showed no evidence of soil contamination at this site. The clean closure justification for CAU 500 is based on these results. Analytes detected were evaluated against preliminary action levels (PALs) to determine contaminants of concern (COCs) for CAU 500, and it was determined that the PALs were not exceeded for total volatile organic compounds, total semivolatile organic compounds, total petroleum hydrocarbons, polychlorinated biphenyls, total Resource Conservation and Recovery Act metals, gamma-emitting radionuclides, isotopic uranium, and strontium-90 for any of the soil samples collected. COCs were identified only within the septic tank and …
Date: February 3, 2000
Creator: United States. National Nuclear Security Administration. Nevada Operations Office.
Object Type: Report
System: The UNT Digital Library
Corrective Action Decision Document for Corrective Action Unit 428: Area 3 Septic Waste Systems 1 and 5, Tonopah Test Range, Nevada (open access)

Corrective Action Decision Document for Corrective Action Unit 428: Area 3 Septic Waste Systems 1 and 5, Tonopah Test Range, Nevada

This Corrective Action Decision Document identifies and rationalizes the US Department of Energy, Nevada Operations Office's selection of a recommended corrective action alternative (CAA) appropriate to facilitate the closure of Corrective Action Unit (CAU) 428, Septic Waste Systems 1 and 5, under the Federal Facility Agreement and Consent Order. Located in Area 3 at the Tonopah Test Range (TTR) in Nevada, CAU 428 is comprised of two Corrective Action Sites (CASs): (1) CAS 03-05-002-SW01, Septic Waste System 1 and (2) CAS 03-05-002- SW05, Septic Waste System 5. A corrective action investigation performed in 1999 detected analyte concentrations that exceeded preliminary action levels; specifically, contaminants of concern (COCs) included benzo(a) pyrene in a septic tank integrity sample associated with Septic Tank 33-1A of Septic Waste System 1, and arsenic in a soil sample associated with Septic Waste System 5. During this investigation, three Corrective Action Objectives (CAOs) were identified to prevent or mitigate exposure to contents of the septic tanks and distribution box, to subsurface soil containing COCs, and the spread of COCs beyond the CAU. Based on these CAOs, a review of existing data, future use, and current operations in Area 3 of the TTR, three CAAs were developed for …
Date: February 8, 2000
Creator: United States. Department of Energy. Nevada Operations Office.
Object Type: Report
System: The UNT Digital Library
Correlation Between Co-60 and X-Ray Exposures on Radiation-Induced Charge Buildup in Silicon-on-Insulator Buried Oxides (open access)

Correlation Between Co-60 and X-Ray Exposures on Radiation-Induced Charge Buildup in Silicon-on-Insulator Buried Oxides

Large differences in charge buildup in SOI buried oxides can result between x-ray and Co-60 irradiations. The effects of bias configuration and substrate type on charge buildup and hardness assurance issues are explored.
Date: February 17, 2000
Creator: Schwank, James R.; Shaneyfelt, Marty R.; Loemker, Rhonda Ann; Draper, Bruce L.; Dodd, Paul E.; Witczak, Steven C. et al.
Object Type: Article
System: The UNT Digital Library
Corrosion tests of 316L and Hastelloy C-22 in simulated tank waste solutions (open access)

Corrosion tests of 316L and Hastelloy C-22 in simulated tank waste solutions

Both the 316L stainless steel and Hastelloy{reg_sign} C-22 gave satisfactory corrosion performance in the simulated test environments. They were subjected to 100 day weight loss corrosion tests and electrochemical potentiodynamic evaluation. This activity supports confirmation of the design basis for the materials of construction of process vessels and equipment used to handle the feed to the LAW-melter evaporator. BNFL process and mechanical engineering will use the information derived from this task to select material of construction for process vessels and equipment.
Date: February 23, 2000
Creator: Danielson, MJ & Pitman, SG
Object Type: Report
System: The UNT Digital Library
Critical current variation of Rutherford cable of Bi-2212 in high magnetic fields with transverse stress (open access)

Critical current variation of Rutherford cable of Bi-2212 in high magnetic fields with transverse stress

None
Date: February 26, 2000
Creator: Dietderich, Daniel R.; Hasegawa, T.; Aoki, Y. & Scanlan, Ronald M.
Object Type: Article
System: The UNT Digital Library
Criticality Safety Evaluation of Hanford Site High Level Waste Storage Tanks (open access)

Criticality Safety Evaluation of Hanford Site High Level Waste Storage Tanks

This criticality safety evaluation covers operations for waste in underground storage tanks at the high-level waste tank farms on the Hanford site. This evaluation provides the bases for criticality safety limits and controls to govern receipt, transfer, and long-term storage of tank waste. Justification is provided that a nuclear criticality accident cannot occur for tank farms operations, based on current fissile material and operating conditions.
Date: February 17, 2000
Creator: ROGERS, C.A.
Object Type: Report
System: The UNT Digital Library
Criticality safety issues in the disposition of BN-350 spent fuel (open access)

Criticality safety issues in the disposition of BN-350 spent fuel

A criticality safety analysis has been performed as part of the BN-350 spent fuel disposition project being conducted jointly by the DOE and Kazakhstan. The Kazakhstan regulations are reasonably consistent with those of the DOE. The high enrichment and severe undermoderation of this fast reactor fuel has significant criticality safety consequences. A detailed modeling approach was used that showed some configurations to be safe that otherwise would be rejected. Reasonable requirements for design and operations were needed, and with them, all operations were found to be safe.
Date: February 28, 2000
Creator: Schaefer, R. W.; Klann, R. T.; Koltyshev, S. M. & Krechetov, S.
Object Type: Article
System: The UNT Digital Library
CRITIQUE OF DUAL CONTINUUM FORMULATIONS OF MULTICOMPONENT REACTIVE TRANSPORT IN FRACTURED POROUS MEDIA (open access)

CRITIQUE OF DUAL CONTINUUM FORMULATIONS OF MULTICOMPONENT REACTIVE TRANSPORT IN FRACTURED POROUS MEDIA

Subsurface flow processes may take place at many different scales. The different scales refer to rock pore structure, micro-fractures, distinct fracture networks ranging from small to large fracture spacing, and even faults. Presently, there is no satisfactory methodology for describing quantitatively flow and reactive transport in multi-scale media. Approaches commonly applied to model fractured systems include single continuum models (SCM), equivalent continuum models (ECM), discrete fracture models (DFM), and various forms of dual continuum models (DCM). The SCM describes flow in the fracture network only and is valid in the absence of fracture-matrix interaction. The ECM, on the other hand, requires pervasive interaction between fracture and matrix and is based on averaging their properties. The ECM is characterized by equal fracture and matrix solute concentrations, but generally different mineral concentrations. The DFM is perhaps the most rigorous, but would require inordinate computational resources for a highly fractured rock mass. The DCM represents a fractured porous medium as two interacting continua with one continuum corresponding to the fracture network and the other the matrix. A coupling term provides mass transfer between the two continua. Vidues for mineral and solute concentrations and other properties such as liquid saturation state maybe assigned individually …
Date: February 1, 2000
Creator: Lichtner, Peter C.
Object Type: Article
System: The UNT Digital Library
Crystal diffraction lens for medical imaging (open access)

Crystal diffraction lens for medical imaging

A crystal diffraction lens for focusing energetic gamma rays has been developed at Argonne National Laboratory for use in medical imaging of radioactivity in the human body. A common method for locating possible cancerous growths in the body is to inject radioactivity into the blood stream of the patient and then look for any concentration of radioactivity that could be associated with the fast growing cancer cells. Often there are borderline indications of possible cancers that could be due to statistical functions in the measured counting rates. In order to determine if these indications are false or real, one must resort to surgical means and take tissue samples in the suspect area. They are developing a system of crystal diffraction lenses that will be incorporated into a 3-D imaging system with better sensitivity (factors of 10 to 100) and better spatial resolution (a few mm in both vertical and horizontal directions) than most systems presently in use. The use of this new imaging system will allow one to eliminate 90% of the false indications and both locate and determine the size of the cancer with mm precision. The lens consists of 900 single crystals of copper, 4 mm x 4 …
Date: February 25, 2000
Creator: Smither, R. K. & Roa, D. E.
Object Type: Article
System: The UNT Digital Library
Cu interactions with {alpha}-Al{sub 2}O{sub 3}(0001): Effects of surface hydroxyl groups vs. dehydroxylation by Ar ion sputtering (open access)

Cu interactions with {alpha}-Al{sub 2}O{sub 3}(0001): Effects of surface hydroxyl groups vs. dehydroxylation by Ar ion sputtering

XPS studies and first principles calculations compare Cu adsorption on heavily hydroxylated sapphire (0001) with a dehydroxylated surface produced by Ar{sup +} sputtering followed by annealing in O{sub 2}. Annealing a cleaned sapphire sample with an O{sub 2} partial pressure of {approximately}5 x 10{sup {minus}6} Torr removes most contaminants, but leaves a surface with {approximately}0.4ML carbon and {approximately}0.4ML OH. Subsequent light (6 min.) Ar ion sputtering at 1 KeV reduces the carbon to undetectable levels but does not dehydroxylate the surface. Further sputtering at higher Ar ion excitation energies (>2 KeV) partially dehydroxylates the surface, while 5 KeV Ar ion sputtering creates oxygen vacancies in the surface region. Further annealing in O{sub 2} repairs the oxygen vacancies in the top layers but those beneath the surface remain. Deposition of Cu on the hydroxylated surface at 300 K results in a maximum Cu(I) coverage of {approximately}0.35 ML, in agreement with theoretical predictions.
Date: February 8, 2000
Creator: Niu, C.; Sheperd, K.; Martini, D.; Kelber, J. A.; Jennison, Dwight R. & Bogicevic, Alexander
Object Type: Article
System: The UNT Digital Library