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Chemical Processing Department Monthly Report
15
Fiscal Year 2004
3
Fiscal Year 2005
3
Fiscal Year 2001
2
Fiscal Year 2007
2
Irradiation Processing Department Monthly Record Report
2
A Novel Membrane Reactor for Direct Hydrogen Production From Coal Progress Report
1
A Real-Time Coal Content/Ore Grade (C2OG) Sensor, Technical Report
1
BEETIT Program
1
Carbon Sequestration on Surface Mine Lands Quarterly Report
1
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3,099 Matching Results
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Hybrid collimation for industrial gamma-ray imaging.
Portable photon imaging devices with a broad energy range of sensitivity, adequate angular resolution and high efficiency are useful in applications such as environmental remediation and industrial surveys. The vast majority of past systems built for these applications have relied on mechanical collimation although a few have used electronic collimation. To our knowledge, no devices have been built that exploit the benefits of both mechanical and electronic collimation in the same system. The combination of a mechanically-collimated camera with an electronically-collimated camera offers both the high efficiency and good angular resolution typical in a mechanically-collimated camera for lower energies and the uncoupling of spatial resolution and efficiency provided by an electronically-collimated camera at higher energies.
Date:
June 22, 1999
Creator:
He, Z.; Knoll, G. F.; Smith, L. E. & Wehe, D. K.
Object Type:
Article
System:
The UNT Digital Library
Recent Results from CDF
We present the latest results from the CDF experiment at the Tevatron Collider in p{bar p} collisions at {radical}s = 1.8 TeV. The large data sample collected during Run 1, from 1992 until 1995, allows measurements in many domains of high-energy physics. Here, we report on the first measurement of sin(2{beta}), a CP violation parameter, and on an improved measurement of the top quark cross section. We also report on searches for the so-far elusive Higgs boson, and for SUSY, through searches for direct production of top and bottom scalar quarks. Finally, we outline the prospects for the physics during the upcoming Run 2, ready to start in the upcoming year 2000.
Date:
December 22, 1999
Creator:
Gallinaro, Michele
Object Type:
Article
System:
The UNT Digital Library
Dynamic equation of state and strength properties of unreacted PBXW-128 explosive
Shock equation of state and strength data have been obtained on the explosive PBXW-128 over the pressure range O-3 GPa using gun impact techniques and velocity interferometry diagnostics. Nonlinear shock-velocity-versus-particle velocity behavior is observed. Possible mechanisms are discussed and a Hug.oniot equation of slate model for the data is provided.
Date:
September 22, 1998
Creator:
Chhabildas, L. C.; Grady, D. E.; Reinhart, W. D. & Wilson, L. T.
Object Type:
Article
System:
The UNT Digital Library
Numerical Models of Broad-Bandwidth Nanosecond Optical Parametric Oscillators
We present three new methods for modeling broad-bandwidth, nanosecond optitcal parametric oscillators in the plane-wave approximation. Each accounts for the group-velocity differences that determine the operating linewidth of unseeded optical parametric oscillators, and each allows the signal and idler waves to develop from quantum noise. The first two methods are based on split-step integration methods in which nonlinear mixing and propagation are calculated separately on alternate steps. One method relies on Fourier transforming handle propagation, wiih mixing integrated over a the fields between t and u to Az step: the other transforms between z and k= in the propagation step, with mixing integrated over At. The third method is based on expansion of the three optical fields in terms of their respective longitudinal empty cavity modes, taking into account the cavity boundary condi- tions. Equations describing the time development of the mode amplitudes are solved to yield the time dependence of the three output fields. These plane-wave models exclude diffractive effects, but can be readily extended to include them.
Date:
October 22, 1998
Creator:
Bowers, M. S.; Gehr, Russell J. & Smith, A. V.
Object Type:
Article
System:
The UNT Digital Library
Privacy: The Small and Large of It
The topic of Privacy is complex, multi-faceted, and often emotionally laden. This paper will cover the following topics, in an effort to further understanding of federal regulations and activities, the balancing act that necessarily occurs in business, and what role a records manager can play. The topics are: Definitions; The Privacy Act; ''Private'' companies; Potential areas of concern; Expectations; Corporate responsibilities; Case studies; and Records Manager's role.
Date:
October 22, 1999
Creator:
NUSBAUM,ANNA W.
Object Type:
Article
System:
The UNT Digital Library
Electrical resistance tomography using steel cased boreholes as electrodes
Electrical resistance tomography (ERT) using multiple electrodes installed in boreholes has been shown to be useful for both site characterization and process monitoring. In some cases, however, installing multiple downhole electrodes is too costly (e.g., deep targets) or risky (e.g., contaminated sites). For these cases we have examined the possibility of using the steel casings of existing boreholes as electrodes. The first case we investigated used an array of steel casings as electrodes. This results in very few data and thus requires additional constraints to limit the domain of possible inverse solutions. Simulations indicate that the spatial resolution and sensitivity are understandably low but it is possible to coarsely map the lateral extent of subsurface processes such as steam floods. A hybrid case uses traditional point electrode arrays combined with long-conductor electrodes (steel casings). Although this arrangement provides more data, in many cases it results in poor reconstructions of test targets. Results indicate that this method may hold promise for low resolution imaging where steel casings can be used as electrodes.
Date:
March 22, 1999
Creator:
Newmark, R. L.; Daily, W. & Ramirez, A.
Object Type:
Article
System:
The UNT Digital Library
First principles calculations for litiated manganese oxides
First principles calculations using the local-spin-density-functional theory are presented of densities of electronic states for MnO, LiMnO{sub 2} in the monoclinic and orthorhombic structures, cubic LiMn{sub 2}O{sub 4} spinel, and {lambda}-MnO{sub 2} (delithiated spinel), all in antiferromagnetic spin configurations. The changes in energy spectra as the Mn oxidation state varies between 2+ and 4+ are illustrated. Preliminary calculations for Co-doped LiMnO{sub 2} are presented, and the destabilization of a monoclinic relative to a rhombohedral structure is discussed.
Date:
December 22, 1998
Creator:
Benedek, R.; Prasad, R.; Thackeray, M. M.; Wills, J. M. & Yang, L. H.
Object Type:
Article
System:
The UNT Digital Library
Internal wave signal processing: A model-based approach
A model-based approach is proposed to solve the oceanic internal wave signal processing problem that is based on state-space representations of the normal-mode vertical velocity and plane wave horizontal velocity propagation models. It is shown that these representations can be utilized to spatially propagate the modal (depth) vertical velocity functions given the basic parameters (wave numbers, Brunt-Vaisala frequency profile etc.) developed from the solution of the associated boundary value problem as well as the horizontal velocity components. These models are then generalized to the stochastic case where an approximate Gauss-Markov theory applies. The resulting Gauss-Markov representation, in principle, allows the inclusion of stochastic phenomena such as noise and modeling errors in a consistent manner. Based on this framework, investigations are made of model-based solutions to the signal enhancement problem for internal waves. In particular, a processor is designed that allows in situ recursive estimation of the required velocity functions. Finally, it is shown that the associated residual or so-called innovation sequence that ensues from the recursive nature of this formulation can be employed to monitor the model`s fit to the data.
Date:
February 22, 1995
Creator:
Candy, J. V. & Chambers, D. H.
Object Type:
Article
System:
The UNT Digital Library
A Low-Voltage Rotary Actuator Fabricated Using a Five-Level Polysilicon Surface Micromachining Technology
The design, fabrication and characterization of a low-voltage rotary stepper motor are presented in this work. Using a five-level polysilicon MEMS technology, steps were taken to increase the capacitance over previous stepper motor designs to generate high torque at low voltages. A low-friction hub was developed to minimize frictional loads due to rubbing surfaces, producing an estimated resistive torque of about 6 pN-m. This design also allowed investigations into the potential benefit of using hard materials such as silicon nitride for lining of both the stationary and rotating hub components. The result is an electrostatic stepper motor capable of operation at less than six volts.
Date:
September 22, 1999
Creator:
Jakubczak, Jerome F., II; Krygowski, Thomas W.; Miller, Samuel L.; Rodgers, M. Steven & Sniegowski, Jeffry J.
Object Type:
Article
System:
The UNT Digital Library
K-Basins S/RIDS
The Standards/Requirements Identification Document(S/RID) is a list of the Environmental, Safety, and Health (ES&H) and Safeguards and Security (SAS) standards/requirements applicable to the K Basins facility
Date:
September 22, 1995
Creator:
Watson, D. J.
Object Type:
Report
System:
The UNT Digital Library
Multilevel Inverters for Electric Vehicle Applications
This paper presents multilevel inverters as an application for all-electric vehicle (EV) and hybrid-electric vehicle (HEV) motor drives. Diode-clamped inverters and cascaded H-bridge inverters, (1) can generate near-sinusoidal voltages with only fundamental frequency switching; (2) have almost no electromagnetic interference (EMI) and common-mode voltage; and (3) make an EV more accessible/safer and open wiring possible for most of an EV'S power system. This paper explores the benefits and discusses control schemes of the cascade inverter for use as an EV motor drive or a parallel HEV drive and the diode-clamped inverter as a series HEV motor drive. Analytical, simulated, and experimental results show the superiority of these multilevel inverters for this new niche.
Date:
October 22, 1998
Creator:
Habetler, Thomas G.; Peng, Fang Z. & Tolbert, Leon M.
Object Type:
Article
System:
The UNT Digital Library
TPX: Contractor preliminary design review. Volume 1, Presentation and design description. Final report
This first volume of the five volume set begins with a CPDR overview and then details the PF magnet system, manufacturing R&D, Westinghouse R&D, the central solenoid, the PF 5 ring coil, the PF 6/7 ring coil, quality assurance, and the system design description.
Date:
September 22, 1995
Creator:
Hartman, D.; Naumovich, G.; Walstrom, P.; Clarkson, I.; Schultheiss, J. & Burger, A.
Object Type:
Report
System:
The UNT Digital Library
Managing safety in a research and development environment
A method for managing safety in a research and development environment is described which involves both the subject matter experts and the researchers in development of safety policy and implementation planning. This method has been used effectively at LLNL to maximize safety benefits while minimizing the costs of the safety program and aggravation to the researcher. A product of this effort is the establishment of an effective safety culture as the line organizations work with the subject matter experts to develop and implement the safety program.
Date:
December 22, 1995
Creator:
Cummings, Garth E.
Object Type:
Article
System:
The UNT Digital Library
Induction heating of a spherical aluminum moderator vessel for the Advanced Neutron Source (ANS)
This task was to identify and design a heating system to apply 15 kW of heat to a cold source vessel to simulate the Advanced Neutron Source reactor. This research project aims at the analysis of the induction heating of a spherical aluminum moderator vessel. Computer modeling is presented for the design and analysis of the induction heating system. The objective is to apply 15 kW of heat as uniformly as possible to the outer wall of a 410 mm diameter sphere of thickness 1.5 mm. The report also aims at the analysis of a system model which is simulated using the Eddycuff electromagnetic software. The computer model is built with the finite element analysis software Patran. The induction heating system analysis shows that the predicted performance is in close agreement with the computer simulated data. Hardware constraints such as power supplies and matching load are also analyzed in terms of performance and cost. Physical modeling is also suggested, in which the coil and the workpiece are scaled down.
Date:
September 22, 1994
Creator:
Yousuf, A.
Object Type:
Report
System:
The UNT Digital Library
Tokamak Physics EXperiment (TPX): Toroidal field magnet design, development and manufacture. SDRL 15, System design description. Volume 1
This System Design Description, prepared in accordance with the TPX Project Management Plan provides a summary or TF Magnet System design features at the conclusion of Phase I, Preliminary Design and Manufacturing Research. The document includes the analytical and experimental bases for the design, and plans for implementation in final design, manufacturing, test, and magnet integration into the tokamak. Requirements for operation and maintenance are outlined, and references to sources of additional information are provided.
Date:
September 22, 1995
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Science of consciousness and the hard problem
Quantum theory is essentially a rationally coherent theory of the interaction of mind and matter, and it allows our conscious thoughts to play a causally efficacious and necessary role in brain dynamics. It therefore provides a natural basis, created by scientists, for the science of consciousness. As an illustration it is explained how the interaction of brain and consciousness can speed up brain processing, and thereby enhance the survival prospects of conscious organisms, as compared to similar organisms that lack consciousness. As a second illustration it is explained how, within the quantum framework, the consciously experienced {open_quotes}I{close_quotes} directs the actions of a human being. It is concluded that contemporary science already has an adequate framework for incorporating causally efficacious experimential events into the physical universe in a manner that: (1) puts the neural correlates of consciousness into the theory in a well defined way, (2) explains in principle how the effects of consciousness, per se, can enhance the survival prospects of organisms that possess it, (3) allows this survival effect to feed into phylogenetic development, and (4) explains how the consciously experienced {open_quotes}I{close_quotes} can direct human behaviour.
Date:
May 22, 1996
Creator:
Stapp, Henry P.
Object Type:
Article
System:
The UNT Digital Library
A study of microclad thickness variation (1987)
A study was conducted to investigate the thickness variation of microclad material used in fabricating 1E38 bridges. For the role sampled (nine reels), standard deviations within reels ranged from 6.11 to 12.07 {mu}in. Thickness variations within reels ranged from 16.2 to 40.9 {mu}in., with the average thickness between 142.90 and 161.28 {mu}in.
Date:
June 22, 1989
Creator:
Ramachandran, R.S. & Armstrong, K.P.
Object Type:
Report
System:
The UNT Digital Library
Vapor and gas sampling of single-shell tank 241-SX-103 using the vapor sampling system
This document presents sampling data resulting from the March 23, 1995, sampling of SST 241-SX-103 using the vapor sampling system.
Date:
September 22, 1995
Creator:
Caprio, G. S.
Object Type:
Report
System:
The UNT Digital Library
Impact studies of five ceramic materials and pyrex
We measured the ballistic performance of five ceramic materials (alumina, silicon carbide, boron carbide, aluminum nitride, and titanium diboride) and Pyrex, when they are backed by thick steel plates. The projectile for all tests was a right-circular cylinder of tungsten sinter-alloy W2 with length 25.4 mm and diameter 6.35 mm, fired at velocities from 1.35 to 2.65 km/s. For this threat we determined the minimum areal density of each material that is needed to keep the projectile from penetrating the backup steel. For all of the facing materials studied here, this performance measure increases approximately linearly with projectile velocity. However, the rate of increase is significantly lower for aluminum nitride than for the other materials studied. Indeed, aluminum nitride is a poor performer at the lowest velocity tested, but is clearly the best at the highest velocity. Our computer simulations show the significant influence of the backing material on ceramic performance, manifested by a transition region extending two projectile diameters upstream from the material interface. Experiments with multiple material layers show that this influence also manifests itself through a significant dependence of ballistic performance on the ordering of the material
Date:
May 22, 1998
Creator:
Cunningham, B. J.; Holt, A. C.; Hord, B. L.; Kusubov, A. S.; Reaugh, J. E. & Wilkins, M. L.
Object Type:
Article
System:
The UNT Digital Library
B plant transition project management plan
The mission of the B Plant Transition Project is to place B Plant and its ancillary facilities (referred to as B Plant throughout this document) in a safe and stable condition which requires minimal long term surveillance and maintenance (S&M), thereby reducing the risks associated with the current radiological and chemical inventory and the costs for S&M until disposition. Transition may include activities such as removal of stored radioactive and hazardous materials, safe shutdown of support systems such as electrical circuits and ventilation, and installation of new or modified systems required to support S&M for a 10 year period. The goal of this Project is to complete B Plant transition activities by September 30, 1998. During transition, the Waste Encapsulation and Storage Facility will be isolated from B Plant for stand alone operation. Upon completion of transition, B Plant will be turned over to the Office of Environmental Restoration (EM-40) for the S&M phase of B Plant decommissioning.
Date:
January 22, 1997
Creator:
Godfrey, S.D.
Object Type:
Report
System:
The UNT Digital Library
Reactive Robinson instability in the NSLS X-ray ring
The theory of the reactive Robinson instability is formulated in terms of the terminal variables, its stopband structure is analysed, and the results are applied to the X-ray ring of the NSLS. The reactive Robinson instability for the case of multiple cavities in the storage ring is also studied.
Date:
January 22, 1996
Creator:
Broome, W.A. & Wang, J.M.
Object Type:
Report
System:
The UNT Digital Library
White paper: A vision for a computing initiative for MFE. Revised version
The scientific base of magnetic fusion research comprises three capabilities: experimental research, theoretical understanding and computational modeling, with modeling providing the necessary link between the other two. The US now faces a budget climate that will preclude the construction of major new MFE facilities and limit MFE experimental operations. The situation is rather analogous to the one experienced by the DOE Defense Programs (DP), in which continued viability of the nuclear stockpile must be ensured despite the prohibition of underground experimental tests. DP is meeting this challenge, in part, by launching the Accelerated Strategic Computing Initiative (ASCI) to bring advanced algorithms and new hardware to bear on the problems of science-based stockpile stewardship (SBSS). ASCI has as its goal the establishment of a ``virtual testing`` capability, and it is expected to drive scientific software and hardware development through the next decade. The authors argue that a similar effort is warranted for the MFE program, that is, an initiative aimed at developing a comprehensive simulation capability for MFE, with the goal of enabling ``virtual experiments.`` It would play a role for MFE analogous to that played by present-day and future (ASCI) codes for nuclear weapons design and by LASNEX for ICF, …
Date:
January 22, 1996
Creator:
Cohen, R.H.; Crotinger, J.A. & Baldwin, D.E.
Object Type:
Report
System:
The UNT Digital Library
Wall surveyor project report
A report is made on the demonstration of a first-generation Wall Surveyor that is capable of surveying the interior and thickness of a stone, brick, or cement wall. LLNL`s Micropower Impulse Radar is used, based on emitting and detecting very low amplitude and short microwave impulses (MIR rangefinder). Six test walls were used. While the demonstrator MIR Wall Surveyor is not fieldable yet, it has successfully scanned the test walls and produced real-time images identifying the walls. It is planned to optimize and package the evaluation wall surveyor into a hand held unit.
Date:
February 22, 1996
Creator:
Mullenhoff, D. J.; Johnston, B. C. & Azevedo, S. G.
Object Type:
Report
System:
The UNT Digital Library
Sandwich Construction Solar Structural Facets
Silver/glass mirrors have excellent optical properties but need a method of support in order to be used in concentrating solar thermal systems. In collaboration with the Cummins dish/Stirling development program, they started investigating sandwich construction as a way to integrate silver/glass mirrors into solar optical elements. In sandwich construction, membranes such as sheet metal or plastic are bonded to the front and back of a core (like a sandwich). For solar optical elements, a glass mirror is bonded to one of the membranes. This type of construction has the advantages of a high strength-to-weight ratio, and reasonable material and manufacturing cost. The inherent stiffness of sandwich construction mirror panels also facilitates large panels. This can have cost advantages for both the amount of hardware required as well as reduced installation and alignment costs. In addition, by incorporating the panels into the support structure reductions in the amount of structural support required are potentially possible.
Date:
December 22, 1998
Creator:
Diver, R. B. & Grossman, J.W.
Object Type:
Article
System:
The UNT Digital Library