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Specificity of model facility agreements under the Chemical Weapons Convention (open access)

Specificity of model facility agreements under the Chemical Weapons Convention

The Chemical Weapons Convention (CWC) contains the most extensive verification inspection provision of any arms control agreement in history. Among its innovations are provisions for facility agreements to govern on-site verification inspections of certain facilities. A facility agreement is an agreement or arrangement between a State Party and the Organization [for the Prohibition of Chemical Weapons] relating to a specific facility subject to on-site verification pursuant to Articles 4, 5 and 6. The purpose of this very brief paper is to discuss the value of specificity in the model facility agreements that are to serve as the basis for facility agreements. The views expressed herein are those of the author alone, and not necessarily those of the government of the US of America or any other institution. The model facility agreements are a key document to national implementation of the CWC. As explained in the Manual for National Implementation of the Chemical Weapons Convention, facility agreements are among the important protections the CWC provides for confidential business information at facilities subject to CWC inspections. Thus, the structure of the models for these agreements will fundamentally determine how national implementation of the Convention will affect various private firms. A particularly salient …
Date: June 27, 1995
Creator: Tanzman, E.A.
System: The UNT Digital Library
Robust controller design of four wheel steering systems using mu synthesis techniques (open access)

Robust controller design of four wheel steering systems using mu synthesis techniques

In this paper, a linearized four wheel steering (4WS) system model is deduced and then modified into a form which is appropriate for applying Matlab {mu} Toolbox to design robust controller. Several important topics are discussed in detail, such as (1) how to make system set-up match Matlab {mu} Toolbox requirement, (2) how to select weights based on plant`s uncertainty, (3) how to solve controller discretization problem, and (4) how to adjust the system so that the conditions necessary for using a state-space formula to solve H{infinity} optimal (sub-optimal) problem and performing the Matlab {mu} Toolbox D--K iteration procedure are satisfied. Finally simulation results of robust controller and a PID controller are compared.
Date: February 27, 1995
Creator: Gao, X.; McVey, B. D. & Tokar, R. L.
System: The UNT Digital Library
Electron Acceleration in Relativistic Plasma Waves Generated by a Single Frequency Short-Pulse Laser (open access)

Electron Acceleration in Relativistic Plasma Waves Generated by a Single Frequency Short-Pulse Laser

Experimental evidence for the acceleration of electrons in a relativistic plasma wave generated by Raman forward scattering (SRS-F) of a single-frequency short pulse laser are presented. A 1.053 {mu}m, 600 fsec, 5 TW laser was focused into a gas jet with a peak intensity of 8{times}10{sup 17} W/cm{sup 2}. At a plasma density of 2{times}10{sup 19} cm{sup {minus}3}, 2 MeV electrons were detected and their appearance was correlated with the anti-Stokes laser sideband generated by SRS-F. The results are in good agreement with 2-D PIC simulations. The use of short pulse lasers for making ultra-high gradient accelerators is explored.
Date: April 27, 1995
Creator: Coverdale, C. A.; Darrow, C. B.; Decker, C. D.; Mori, W. B.; Tzeng, K. C.; Clayton, C. E. et al.
System: The UNT Digital Library
Multiple mechanisms in the thermally activated plastic flow of tantalum (open access)

Multiple mechanisms in the thermally activated plastic flow of tantalum

We argue that many of the features of the plastic flow behavior of tantalum can be described by a model that incorporates a two-component Peierls-type mechanism and an fcc-like obstacle mechanism in series. We compare the results of calculations based on such a model with flow data for unalloyed tantalum over a wide range of strain rates and a modest range of temperatures.
Date: June 27, 1995
Creator: Gourdin, W.H. & Lassila, D.H.
System: The UNT Digital Library
Testing of stripping columns for the removal of benzene from aqueous radioactive salt solution (open access)

Testing of stripping columns for the removal of benzene from aqueous radioactive salt solution

Radioactive high level wastes (HLW) generated from production of special nuclear materials at the Savannah River Site (SRS) are held in interim storage in 51 underground, million gallon tanks. Radioactive cesium ({sup 137}Cs) is segregated by evaporation of aqueous waste solution for interim storage in a salt matrix comprised of Na and K salts or in concentrated salt solution. The saltcake will be dissolved and {sup 137}Cs will be separated from the nonradioactive salts in solution in the In-Tank Precipitation (ITP) Process. The cesium will be combined with other radioactive species and glass formers to be melted and poured into stainless steel canisters in the Defense Waste Processing Facility (DWPF). The salt solution remaining after decontamination in the ITP process will be incorporated into grout for disposal at the site`s Saltstone facility. In the ITP facility, sodium tetraphenylborate (STPB) will be added to precipitate the cesium. Potassium in the waste solution also reacts with STPB and precipitates. Due to radiolytic and chemical degradation of the tetraphenylborate (TPB) precipitate, benzene is generated. The benzene dissolves into the decontaminated salt solution (DSS) and into water (WW) used to {open_quotes}wash{close_quotes} the precipitate to lower the soluble salt content of the slurry. Safety and …
Date: June 27, 1995
Creator: Georgeton, G. K.; Taylor, G. A. & Gaughan, T. P.
System: The UNT Digital Library
Perturbation theory for frequency doubling and tripling of electric field amplitude and phase ripples (open access)

Perturbation theory for frequency doubling and tripling of electric field amplitude and phase ripples

A perturbation theory has been developed to calculate the transfer of electric field amplitude and phase ripples from the first harmonic to either the second harmonic or the third harmonic. The theory is restricted to steady-state conversion processes. In the case of small phase gradients, the real and imaginary parts of the output harmonic ripple are related to the real and imaginary parts of the input perturbation by a 2 {times} 2 matrix. To confirm the validity of the perturbation theory, we have performed an initial set of experiments on the Optical Sciences Laser to investigate the transfer of a weak ripple from the first harmonic to the second harmonic.
Date: June 27, 1995
Creator: Auerbach, J. M.; Eimerl, D.; Hunt, J. T.; Milam, D.; Trenholme, J. B. & Milonni, P. W.
System: The UNT Digital Library
LLNL pure positron plasma program (open access)

LLNL pure positron plasma program

Assembly and initial testing of the Positron Time-of-Flight Trap at the Lawrence Livermore National Laboratory (LLNL) Increase Pulsed Positron Facility has been completed. The goal of the project is to accumulate at high-density positron plasma in only a few seconds., in order to facilitate study that may require destructive diagnostics. To date, densities of at least 6 {times} 10{sup 6} positrons per cm{sup 3} have been achieved.
Date: September 27, 1995
Creator: Hartley, J. H.; Beck, B. R.; Cowan, T. E.; Howell, R. H.; McDonald, J. L.; Rohatgi, R. R. et al.
System: The UNT Digital Library
Engineering Model of Liquid Storage Utility Tank for Heat Transfer Analysis (open access)

Engineering Model of Liquid Storage Utility Tank for Heat Transfer Analysis

The utility or chemical storage tank requires special engineering attention and heat transfer analysis because the tank content is very sensitive to temperature and surrounding environment such as atmospheric or outside air, humidity, and solar radiation heat. A simplified heat transfer model was developed to calculate the liquid content temperature of utility storage tank. The content of the utility storage tanks can be water or any other chemical liquid. An engineering model of liquid storage tank for heat transfer analysis and temperature calculations are presented and discussed in the examples of Tanks No. 1 containing oxalic acid and No. 2 containing sodium tetraphenylborate solution.
Date: September 27, 1995
Creator: Kwon, K.C.
System: The UNT Digital Library
Immobilization as a route to surplus fissile materials disposition (open access)

Immobilization as a route to surplus fissile materials disposition

In the aftermath of the Cold War, the US and Russia have agreed to large reductions in nuclear weapons. To aid in the selection of long-term management options, DOE has undertaken a multifaceted study to select options for storage and disposition of plutonium (Pu) in keeping with the national policy that Pu must be subjected to the highest standards of safety, security, and accountability. One alternative being considered is immobilization. To arrive at a suitable immobilization form, the authors first reviewed published information on high-level waste (HLW) immobilization technologies in order to identify 72 possible Pu immobilization forms to be prescreened. Surviving forms were screened using multiattribute analysis to determine the most promising technologies. Promising immobilization families were further evaluated to identify chemical, engineering, environmental, safety, and health problems that remain to be solved prior to making technical decisions as to the viability of using the form for long-term disposition of plutonium. All data, analyses, and reports are being provided to the DOE Fissile Materials Disposition Project Office to support the Record of Decision that is anticipated in the fourth quarter of FY96.
Date: April 27, 1995
Creator: Gray, L.W. & Kan, T.
System: The UNT Digital Library
Direct conversion of plutonium-containing materials to borosilicate glass for storage or disposal (open access)

Direct conversion of plutonium-containing materials to borosilicate glass for storage or disposal

A new process, the Glass Material Oxidation and Dissolution System (GMODS), has been invented for the direct conversion of plutonium metal, scrap, and residue into borosilicate glass. The glass should be acceptable for either the long-term storage or disposition of plutonium. Conversion of plutonium from complex chemical mixtures and variable geometries into homogeneous glass (1) simplifies safeguards and security; (2) creates a stable chemical form that meets health, safety, and environmental concerns; (3) provides an easy storage form; (4) may lower storage costs; and (5) allows for future disposition options. In the GMODS process, mixtures of metals, ceramics, organics, and amorphous solids containing plutonium are fed directly into a glass melter where they are directly converted to glass. Conventional glass melters can accept materials only in oxide form; thus, it is its ability to accept materials in multiple chemical forms that makes GMODS a unique glass making process. Initial proof-of-principle experiments have converted cerium (plutonium surrogate), uranium, stainless steel, aluminum, and other materials to glass. Significant technical uncertainties remain because of the early nature of process development.
Date: June 27, 1995
Creator: Forsberg, C. W. & Beahm, E. C.
System: The UNT Digital Library
Gamma Ray Burst Optical Counterpart Search Experiment (GROCSE) (open access)

Gamma Ray Burst Optical Counterpart Search Experiment (GROCSE)

GROCSE (Gamma-Ray Optical Counterpart Search Experiments) is a system of automated telescopes that search for simultaneous optical activity associated with gamma ray bursts in response to real-time burst notifications provided by the BATSE/BACODINE network. The first generation system, GROCSE 1, is sensitive down to Mv {approximately} 8.5 and requires an average of 12 seconds to obtain the first images of the gamma ray burst error box defined by the BACODINE trigger. The collaboration is now constructing a second generation system which has a 4 second slewing time and can reach Mv {approximately} 14 with a 5 second exposure. GROCSE 2 consists of 4 cameras on a single mount. Each camera views the night sky through a commercial Canon lens (f/1.8, focal length 200 mm) and utilizes a 2K x 2K Loral CCD. Light weight and low noise custom readout electronics were designed and fabricated for these CCDs. The total field of view of the 4 cameras is 17.6 x 17.6 {degree}. GROCSE II will be operated by the end of 1995. In this paper, the authors present an overview of the GROCSE system and the results of measurements with a GROCSE 2 prototype unit.
Date: October 27, 1995
Creator: Park, Hye-Sook; Ables, Elden; Bionta, Richard M.; Ott, Linda; Parker, Eric; Akerlof, Carl et al.
System: The UNT Digital Library
Results from GROCSE I: A real-time search for gamma ray burst optical counterparts (open access)

Results from GROCSE I: A real-time search for gamma ray burst optical counterparts

The GROCSE I experiment (Gamma-Ray Optical Counterpart Search Experiment) is a rapid slewing wide field of view optical telescope at Lawrence Livermore National Laboratory which responds to triggers from the BATSE GRB data telemetry stream that have been processed and distributed by the BACODINE network. GROCSE 1 has been in continuous automated operation since January 1994. As of October 1995, sky images for 22 GRB triggers have been recorded, in some cases while the burst was still emitting gamma rays. The preliminary analysis of eight of these events are presented here. No optical counterparts have yet been detected. Limits for optical emission are given.
Date: October 27, 1995
Creator: Lee, B.; Akerlof, C. & Ables, E.
System: The UNT Digital Library
Diverse topics in crystalline beams (open access)

Diverse topics in crystalline beams

Equations of motion are presented, appropriate to interacting charged particles of diverse charge and mass, subject to the external forces produced by various kinds of magnetic fields and radio-frequency (rf) electric fields in storage rings. These equations are employed in the molecular dynamics simulations to study the properties of crystalline beams. The two necessary conditions for the formation and maintenance of crystalline beams are summarized. The transition from ID to 2D, and from 2D to 3D is explored, and the scaling behavior of the heating rates is discussed especially in the high temperature limit. The effectiveness of various cooling techniques in achieving crystalline states has been investigated. Crystalline beams made of two different species of ions via sympathetic cooling are presented, as well as circulating ``crystal balls`` bunched in all directions by magnetic focusing and rf field. By numerically reconstructing the original experimental conditions of the NAP-M ring, it is found that only at extremely low beam intensities, outside of the range of the original measurement, proton particles can form occasionally-passing disks. The proposed New ASTRID ring is shown to be suitable for the formation and maintenance of crystalline beams of all dimensions.
Date: November 27, 1995
Creator: Wei, Jie; Draeseke, A.; Sessler, A. M. & Li, Xiao-Ping
System: The UNT Digital Library
Effects of longitudinal space charge in beams for heavy-ion fusion (open access)

Effects of longitudinal space charge in beams for heavy-ion fusion

A new analytic model is presented that accurately estimates the radially averaged axial component of the space-charge field of an axisymmetric heavy-ion beam in a cylindrical beam pipe. The model recovers details of the field near the beam ends that are overlooked by simpler models, and the results compare well to exact solutions of Poisson`s equation. Field values are shown for several simple beam profiles and are compared with values obtained from simpler models. The model has been implemented in the fluid/envelope code CIRCE and used to study longitudinal confinement in beams with a variety of axial profiles. The effects of errors in the longitudinal-control fields are presented.
Date: December 27, 1995
Creator: Sharp, W. M.; Friedman, A. & Grote, D. P.
System: The UNT Digital Library
X-ray radiography of fracture flow and matrix imbibition (open access)

X-ray radiography of fracture flow and matrix imbibition

Knowledge of how water flows through unsaturated, fractured rock is critical for understanding and predicting the performance of a high- level nuclear waste repository. For instance, during gravity driven fracture flow, the distance that water can travel through a fracture network might be controlled by (1) the amount of water available, (2) the fracture aperture, (3) the capillary properties of the matrix, and (4) the saturation of the matrix. We have experimentally investigated fracture flow and fracture-matrix interactions using x- ray radiography to image some of the above factors and processes.
Date: October 27, 1995
Creator: Roberts, J. J. & Lin, Wunan
System: The UNT Digital Library
Relative humidity in the near-field environment (open access)

Relative humidity in the near-field environment

The Yucca Mountain Site Characterization Project is investigating Yucca Mountain, Nevada, for its suitability as a potential repository for high-level nuclear wastes. United States federal regulation 10CFR60 requires that radioactive nuclides be substantially contained in waste packages for 300 to 1000 years after the emplacement. To meet the regulation, a waste package container should remain intact for several hundreds of years. It has been shown that high humidity increases the corrosion potential of metallic container materials. Relative humidity as a function of water saturation in intact rock is measured. The results of this test can be used to calibrate the relative humidity in the near-field environment predicted by model calculations using thermal-hydrological codes such as VTOUGH. This is a report on the progress of that experiment.
Date: October 27, 1995
Creator: Lin, W.; Roberts, J. & Ruddle, D
System: The UNT Digital Library
High-resolution gamma-ray measurement systems using a compact electro- mechanically cooled detector system and intelligent software (open access)

High-resolution gamma-ray measurement systems using a compact electro- mechanically cooled detector system and intelligent software

Obtaining high-resolution gamma-ray measurements using high-purity germanium (HPGe) detectors in the field has been of limited practicality due to the need to use and maintain a supply of liquid nitrogen (LN{sub 2}). This same constraint limits high-resolution gamma measurements in unattended safeguards or treaty Verification applications. We are developing detectors and software to greatly extend the applicability of high-resolution germanium-based measurements for these situations.
Date: September 27, 1995
Creator: Buckley, W. M.; Carlson, J. B. & Neufeld, K. W.
System: The UNT Digital Library
Energetic charged particle beams for disablement of mines (open access)

Energetic charged particle beams for disablement of mines

LLNL has an ongoing program of weapons disablement using energetic charged particle beams; this program combines theoretical and experimental expertise in accelerators, high-energy and nuclear physics, plasma physics and hydrodynamics to simulate/measure effects of electron and proton beams on weapons. This paper reviews work by LLNL, LANL and NSWC on detonating sensitive and insensitive high explosives and land mines using high-current electron beams. Computer simulations are given. 20--160 MeV electron beams incident on wet/dry soils are being studied, along with electron beam propagation in air. Compact high current, high energy accelerators are being developed for mine clearing. Countermine missions of interest are discussed. 25 refs., 9 figs.
Date: March 27, 1995
Creator: Wuest, C.R.
System: The UNT Digital Library
The central peak revisited (open access)

The central peak revisited

The central peak in SrTiO{sub 3} was first observed by Riste and his collaborators in 1971. This was one of the key discoveries leading to an understanding of the dynamics of phase transitions. The most recent discovery of two length scales in SrTiO{sub 3} motivated a reinvestigation of the soft phonon and associated central peak by neutron scattering. These recent experiments shed new light on the nature of the central peak. It is now well established to be strongly sample dependent and it originates from defects in bulk crystals.
Date: October 27, 1995
Creator: Shirane, G.
System: The UNT Digital Library
Measurements of a 1/4-scale model of a 60-kg explosives firing chamber (open access)

Measurements of a 1/4-scale model of a 60-kg explosives firing chamber

In anticipation of increasingly stringent environmental regulations, Lawrence Livermore National Laboratory (LLNL) proposes to construct a 60-kg firing chamber to provide blast-effects containment for, most of its open-air, high-explosive, firing operations. Even though these operations are within current environmental limits, containment of the blast effects and hazardous debris will further drastically reduce emissions to the environment and minimize the generated hazardous waste. The major design consideration of such a chamber is its overall structural dynamic response in terms of long-term containment of all blast effects from repeated internal detonations of high explosives. Another concern is how much other portions of the facility must be hardened to ensure personnel protection in the event of an accidental detonation. To assess these concerns, a 1/4-scale replica model of the planned contained firing chamber was designed, constructed, and tested with scaled explosive charges ranging from 25 to 125% of the operational explosives limit of 60 kg. From 16 detonations of high explosives, 880 resulting strains, blast pressures, and temperatures within the model were measured. Factors of safety for dynamic yield of the firing chamber structure were calculated and compared to the design criterion of totally elastic response. The rectangular, reinforced-concrete chamber model exhibited a …
Date: January 27, 1995
Creator: Pastrnak, J.W.; Baker, C.F. & Simmons, L.F.
System: The UNT Digital Library
Measurements of a 1/4-scale model of an explosives firing chamber (open access)

Measurements of a 1/4-scale model of an explosives firing chamber

In anticipation of increasingly stringent environmental regulations, Lawrence Livermore National Laboratory (LLNL) proposes to construct a 60-kg firing chamber to provide blast-effects containment for most of its open-air, high-explosive, firing operations. Even though these operations are within current environmental limits, containment of the blast effects and hazardous debris will further drastically reduce emissions to the environment and minimize the generated hazardous waste. The major design consideration of such a chamber is its overall structural dynamic response in terms of long-term containment of all blast effects from repeated internal detonations of high explosives. Another concern is how much other portions of the facility outside the firing chamber must be hardened to ensure personnel protection in the event of an accidental detonation while the chamber door is open. To assess these concerns, a 1/4-scale replica model of the planned contained firing chamber was designed, constructed, and tested with scaled explosive charges ranging from 25 to 125% of the operational explosives limit of 60 kg. From 16 detonations of high explosives, 880 resulting strains, blast pressures, and temperatures within the model were measured to provide information for the final design. Factors of safety for dynamic yield of the firing chamber structure were calculated …
Date: January 27, 1995
Creator: Pastrnak, J. W.; Baker, C. F. & Simmons, L. F.
System: The UNT Digital Library
Startup and Operation of a Metal Hydride Based Isotope Separation Process (open access)

Startup and Operation of a Metal Hydride Based Isotope Separation Process

Production scale separation of tritium from other hydrogen isotopes at the Savannah River Site (SRS) in Aiken, SC, has been accomplished by several methods. These methods include thermal diffusion (1957--1986), fractional absorption (1964--1968), and cryogenic distillation (1967-present). Most recently, the Thermal Cycling Absorption Process (TCAP), a metal hydride based hydrogen isotope separation system, began production in the Replacement Tritium Facility (RTF) on April 9, 1994. TCAP has been in development at the Savannah River Technology Center since 1980. The production startup of this semi-continuous gas chromatographic separation process is a significant accomplishment for the Savannah River Site and was achieved after years of design, development, and testing.
Date: February 27, 1995
Creator: Scogin, J. H. & Poore, A. S.
System: The UNT Digital Library
A probabilistic risk assessment of the LLNL Plutonium Facility`s evaluation basis fire operational accident. Revision 1 (open access)

A probabilistic risk assessment of the LLNL Plutonium Facility`s evaluation basis fire operational accident. Revision 1

The Lawrence Livermore National Laboratory (LLNL) Plutonium Facility conducts numerous programmatic activities involving plutonium to include device fabrication, development of improved and/or unique fabrication techniques, metallurgy research, and laser isotope separation. A Safety Analysis Report (SAR) for the building 332 Plutonium Facility was completed in July 1994 to address operational safety and acceptable risk to employees, the public, government property, and the environmental. This paper outlines the PRA analysis of the Evaluation Basis Fire (EBF) operational accident. The EBF postulates the worst-case programmatic impact event for the Plutonium Facility.
Date: February 27, 1995
Creator: Brumburgh, G.P.
System: The UNT Digital Library
The gene identification problem: An overview for developers (open access)

The gene identification problem: An overview for developers

The gene identification problem is the problem of interpreting nucleotide sequences by computer, in order to provide tentative annotation on the location, structure, and functional class of protein-coding genes. This problem is of self-evident importance, and is far from being fully solved, particularly for higher eukaryotes, Thus it is not surprising that the number of algorithm and software developers working in this area is rapidly increasing. The present paper is an overview of the field, with an emphasis on eukaryotes, for such developers.
Date: March 27, 1995
Creator: Fickett, J.W.
System: The UNT Digital Library