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Tumor production in Syrian hamsters following inhalation of PuO/sub 2/--ZrO/sub 2/ aerosol (open access)

Tumor production in Syrian hamsters following inhalation of PuO/sub 2/--ZrO/sub 2/ aerosol

Syrian golden hamsters of both sexes were exposed to aerosols of ZrO/sub 2/ containing PuO/sub 2/. The starting material in the aerosol generator also had a small amount of /sup 57/Co added as a tracer. The mixture of all three constituents was nebulized and the droplets passed through a heating column at 1000/sup 0/C. Aerosol sampling was accomplished with a cascade impactor and electrostatic precipitator. The median aerodynamic diameters in all inhalation runs were approximately 2 ..mu..m with a geometric standard deviation of 2. One exposed group of 60 hamsters had 6-day lung burdens averaging 100 nCi. This group had a lung tumor incidence of 44% with an even distribution of adenomas and carcinomas. Two other groups had average 6-day lung burdens of 80 to 90 nCi plus 55 nCi of intravenously injected spheres localized in the lung. These animals had tumor incidences of approximately 30%.
Date: January 1, 1978
Creator: Thomas, R. G. & Smith, D. M.
System: The UNT Digital Library
Validation and sensitivity of a simulated photograph technique for visibility modeling (open access)

Validation and sensitivity of a simulated photograph technique for visibility modeling

The Los Alamos Scientific Laboratory (LASL) visibility model is capable of producing simulated before and after pictures that illustrate visual effects of smoke plumes. Although the model has been under development for a few years, until recently there had been very little testing of the model against field experience or testing of sensitivity of the model results to numerical approximations used in the model. Further validation and sensitivity testing of the LASL model began in late 1979. The work focused on three areas: comparison of the LASL model results with plumes encountered in the field, comparison of LASL background-atmosphere model results with measured sky intensities, and examination of the variation of model results with changes in the numerical approximations. The field study took place during August of 1979 in the vicinity of coal-fired power plants in northwestern New Mexico and northern Arizona. Telephotometer, NO/sub X/ plume measurements, and aerosol size distribution measurements were made in the plumes of three different coal-fired power plants. Photographs were taken of the plumes, and simulated photographs were prepared by the model. Light intensities calculated by the background radiative transfer model were compared to measured light intensities in a very clean atmosphere and in a …
Date: January 1, 1980
Creator: Williams, M.; Chan, L.Y. & Lewis, R.
System: The UNT Digital Library
Programmable multi-timer for TRU waste analysis applications (open access)

Programmable multi-timer for TRU waste analysis applications

A programmable, multiple-function timing module has been developed for use in transuranic (TRU) waste analysis applications at the Idaho National Engineering Laboratory. The Programmable Multi-Timer (PRMT) is an expanded version of a module originally built for accelerator-based active photon interrogation experiments. During the course of the experiments, it became obvious that a more versatile timer was needed to meet several unforeseen requirements. The PRMT was designed to meet the new requirements and to serve as a general-purpose timing module for other applications.
Date: January 1, 1981
Creator: Lawrence, R.S.; Nieschmidt, E.B. & Tsang, F.Y.
System: The UNT Digital Library
Issues for trigger processing at high luminosity colliders (open access)

Issues for trigger processing at high luminosity colliders

A number of issues for the design of trigger processors at future high-luminosity, high-energy colliders such as the Superconducting Super Collider and the Large Hadron Collider are discussed.
Date: November 1, 1989
Creator: Lankford, A.J.
System: The UNT Digital Library
Computation of self-consistent 2-D MHD with neutral-beam and bootstrap currents in elongated plasmas (open access)

Computation of self-consistent 2-D MHD with neutral-beam and bootstrap currents in elongated plasmas

The observation of substantial current drive from neutral beam injection (NBI) in TFTR, JET and DIII-D has led to renewed interest in a steady state, non-inductively driven tokamak. The discovery of apparently considerable neoclassical (bootstrap) current in TFTR, makes a steady state device even more attractive since the bootstrap portion of the current could be obtained without additional power input. Motivated by these results, we have developed a code, ACCOME, which self-consistently computes the 2-D MHD equilibrium with the current driven by neutral beams, bootstrap and the electric field. In this paper we first describe some details of the code in the next section and in the subsequent section show some applications to DIII-D and to a possible ITER design.
Date: April 5, 1983
Creator: Devoto, R. S.; Tani, K. & Azumi, M.
System: The UNT Digital Library
First wall/blanket/shield design and optimization system (open access)

First wall/blanket/shield design and optimization system

First wall/blanket/shield design and optimization system (BSDOS) has been developed to provide a state-of-the-art design tool for fast accurate analysis. In addition, it has been designed to perform several other functions: (1) allowing comparison and evaluation studies for different concepts using the same data bases and ground rules, (2) permitting the use of any figure of merit in the evaluation studies, (3) optimizing the first wall/blanket/shield design parameters for any figure of merit under several design constraints, (4) permitting the use of different reactor parameters in the evaluation and optimization analyses, (5) allowing the use of improved eingineering data bases to study the impact on the design performance for planning future research and development, and (6) evaluating the effect of the data base uncertainties on the design performance. BSDOS is the first design and optimization system to couple the highly interacting neutronics, heat transfer, thermal hydraulics, stress analysis, radioactivity and decay-heat analyses, tritium balance, and capital cost. A brief description of the main features of BSDOS is given in this paper. Also, results from using BSDOS to perform design analysis for several reactor components are presented. 17 refs., 1 fig., 2 tabs.
Date: February 1, 1988
Creator: Gohar, Y.; Baker, C.; Attaya, H.; Cha, Y.; Majumdar, S. & Scandora, T.
System: The UNT Digital Library
The (t,d) reaction on the Ni isotopes with polarized tritons (open access)

The (t,d) reaction on the Ni isotopes with polarized tritons

The (t vector,d) reaction has been measured on targets of /sup 58/ /sup 60/ /sup 62/ /sup 64/Ni with 17 MeV polarized tritons. Spectroscopic factors, angular momentum and total spin transfer were obtained from the differential cross section and A/sub y/ values of levels up to 3.5 MeV in excitation energy. The present (t,d) measurement enables a better description of the 9/2/sup +/ and 5/2/sup +/ states which show significant shell crossing effects as a function of increasing neutron number.
Date: January 1, 1980
Creator: Flynn, E. R.; Cizewski, J. A.; Brown, R. E.; Hardekopf, R. A. & Sunier, J. W.
System: The UNT Digital Library
Alignment and orientation in ion/endash/atom collisions (open access)

Alignment and orientation in ion/endash/atom collisions

Recent progress in the theoretical study of alignment and orientation in atom-atom and ion-atom collisions at intermediate energies is reviewed. Recent systematic studies of the alignment and orientation of electronic charge cloud distributions of excited states resulting from such collisions clearly have provided more detailed information about the underlying collision dynamics. However, since accurate determination of these parameters is quite difficult, both theoretically and experimentally, a close collaboration between theory and experiment is necessary for a deeper understanding of the collision dynamics. A more complete approach, where the full density matrix is determined, is also discussed.
Date: January 1, 1987
Creator: Kimura, M. & Lane, N.F.
System: The UNT Digital Library
Stochastic model of radioiodine transport (open access)

Stochastic model of radioiodine transport

A research project has been underway at the Oak Ridge National Laboratory with the objective to evaluate dose assessment models and to determine the uncertainty associated with the model predictions. This has resulted in the application of methods to propagate uncertainties through models. Some techniques and results related to this problem are discussed.
Date: January 1, 1980
Creator: Schwarz, G. & Hoffman, F.O.
System: The UNT Digital Library
High-Sensitivity Single-Molecule Fluorescence Detection in Theory and Practice (open access)

High-Sensitivity Single-Molecule Fluorescence Detection in Theory and Practice

The number of emitted photons that can be obtained from a fluorophore increases with the incident light intensity and the duration of illumination. However, saturation of the absorption transition and photodestruction place natural limits on the ultimate signal-to-noise ratio that can be obtained. Equations have been derived to describe the fluorescence-to-background-noise ratio in the presence of saturating light intensities and photodestruction. The fluorescence lifetime and the photodestruction quantum yield are the key parameters that determine the optimum light intensity and exposure time. To test this theory we have performed single molecule detection of phycoerythrin (PE). The laser power was selected to give a mean time between absorptions approximately equal to the fluorescence decay rate. The transit time was selected to be nearly equal to the photodestruction time of {approximately}600 {mu}s. Under these conditions the photocount distribution function, the photocount autocorrelation function, and the concentration dependence clearly show that we are detecting bursts of fluorescence from individual fluorophores. A hard-wired version of this single-molecule detection system was used to measure the concentration of PE down to 10{sup {minus}15} M. This single-molecule counter is three orders-of-magnitude more sensitive than conventional fluorescence detection systems. The approach presented here should be useful in the …
Date: 1989
Creator: Mathies, R. A.; Peck, K. & Stryer, L.
System: The UNT Digital Library
Lost circulation technology development status (open access)

Lost circulation technology development status

Lost circulation is the loss of drilling fluid from the wellbore to fractures or pores in the rock formation. In geothermal drilling, lost circulation is often a serious problem that contributes greatly to the cost of the average geothermal well. The Lost Circulation Technology Development Program is sponsored at Sandia National Laboratories by the US Department of Energy. The goal of the program is to reduce lost circulation costs by 30--50% through the development of mitigation and characterization technology. This paper describes the technical progress made in this program during the period April 1991--March 1992. 8 refs.
Date: January 1, 1992
Creator: Glowka, D. A.; Schafer, D. M.; Loeppke, G. E.; Scott, D. D.; Wernig, M. D. & Wright, E. K.
System: The UNT Digital Library
Creating a word list for technical and clerical personnel (open access)

Creating a word list for technical and clerical personnel

The Savannah River Plant and Laboratory employ more than 16,000 people. When the separate Publications Divisions of the Plant and Laboratory were combined it was determined that a single source of information for using terms was needed, and that the source would take the form of a word list. The Word List was issued to more than 5000 employees onsite. In addition, the Word List is being added to the site computer network as a reference document and as an online spelling checker where more than 2000 employees will have access to it through their personal computers.
Date: May 1, 1988
Creator: Hammond, J S
System: The UNT Digital Library
Proceedings of the flat-plate solar array project research forum on photovoltaic metallization systems (open access)

Proceedings of the flat-plate solar array project research forum on photovoltaic metallization systems

A Photovoltaic Metallization Research Forum, under the sponsorship of the Jet Propulsion Laboratory's Flat-Plate Solar Array Project and the US Department of Energy, was held March 16-18, 1983 at Pine Mountain, Georgia. The Forum consisted of five sessions, covering (1) the current status of metallization systems, (2) system design, (3) thick-film metallization, (4) advanced techniques and (5) future metallization challenges. Twenty-three papers were presented.
Date: November 15, 1983
Creator: unknown
System: The UNT Digital Library
/sup 16/O + /sup 40/Ca inelastic scattering and the elastic scattering wave function (open access)

/sup 16/O + /sup 40/Ca inelastic scattering and the elastic scattering wave function

The /sup 16/O + /sup 40/Ca inelastic scattering has been measured at 60-MeV incident energy, and evidence has been found in support of an explicit coupling between direct and elastic channels. The measurements were extended over a large angular range and in particular to very forward angles. The ratio of cross sections between extreme forward and backward angles proved very useful in studying the underlying reaction mechanism.
Date: January 1, 1977
Creator: Rehm, K.E.; Henning, W.; Erskine, J.R. & Kovar, D.G.
System: The UNT Digital Library
Microscopic and semi-classical treatments of octupole deformation in the light actinides (open access)

Microscopic and semi-classical treatments of octupole deformation in the light actinides

Microscopic and semi-classical descriptions of octupole deformation are compared. New semi-classical results, obtained with the use of a Woods-Saxon potential are presented. Comparisons with experiment are made. 21 references.
Date: January 1, 1984
Creator: Chasman, R.R.
System: The UNT Digital Library
Approach to decision modeling for an ignition test reactor (open access)

Approach to decision modeling for an ignition test reactor

A comparison matrix decision model is applied to candidates for a D-T ignition tokamak (TNS), including assessment of semi-quantifiable or judgemental factors as well as quantitative ones. The results show that TNS is mission-sensitive with a choice implied between near-term achievability and reactor technology.
Date: September 30, 1977
Creator: Howland, H.R. & Varljen, T.C.
System: The UNT Digital Library
Potential for use of high-temperature superconductors in fusion reactors (open access)

Potential for use of high-temperature superconductors in fusion reactors

The present rate of development of high-temperature superconductors (HTSs) is sufficiently rapid that there may be opportunities for their use in contemporary fusion devices such as the International Thermonuclear Experimental Reactor (ITER). The most likely 1application is for delivering power to the superconducting magnets, especially in substituting for the current leads between the temperatures of 4 K and 77K. A second possible application of HTSs is as a liquid-nitrogen-cooled power bus, connecting the power supplies to the magnets, thus reducing the ohmic heating losses over these relatively long cables. A third potential application of HTSs is as an inner high-field winding of the toroidal field coils that would operate at {approx}20 K. While the use of higher temperature magnets offers significant advantages to the reactor system, it is unlikely that tested conductors of this type will be available within the ITER time frame. 23 refs., 2 figs.
Date: January 1, 1991
Creator: Hull, J.R.
System: The UNT Digital Library
Technician support for operation and maintenance of large fusion experiments: the tandem mirror experiment upgrade (TMX-U) approach (open access)

Technician support for operation and maintenance of large fusion experiments: the tandem mirror experiment upgrade (TMX-U) approach

As experiments continue to grow in size and complexity, a few technicians will no longer be able to maintain and operate the complete experiment. Specialization is becoming the norm. Subsystems are becoming very large and complex, requiring a great deal of experience and training for technicians to become qualified maintenance/operation personnel. Formal in-house and off-site programs supplement on-the-job training to fulfill the qualification criteria. This paper presents the Tandem Mirror Experiment-Upgrade (TMX-U) approach to manpower staffing, some problems encountered, possible improvements, and safety considerations for the successful operation of a large experimental facility.
Date: December 1, 1983
Creator: Mattson, G.E.
System: The UNT Digital Library
Decontamination of Savannah River Plant H-Area hot-canyon crane (open access)

Decontamination of Savannah River Plant H-Area hot-canyon crane

Decontamination techniques applicable to the remotely operated bridge cranes in canyon buildings at the Savannah River Plant (SRP) were identified and were evaluated in laboratory-scale tests. High pressure Freon blasting was found to be the most attractive process available for this application. Strippable coatings were selected as an alternative technique in selected applications. The ability of high pressure Freon blasting plus two strippable coatings (Quadcoat 100 and Alara 1146) to remove the type of contamination expected on SRP cranes was demonstrated in laboratory-scale tests. Quadrex HPS was given a contract to decontaminate the H-Area hot canyon crane. Decontamination operations were successfully carried out within the specified time-frame window. The radiation level goals specified by SRP were met and decontamination was accomplished with 85% less personnel exposure than estimated by SRP before the job started. This reduction is attributed to the increased efficiency of the new decontamination techniques used. 6 refs., 1 tab.
Date: January 1, 1985
Creator: Rankin, W N & Sims, J R
System: The UNT Digital Library
Effects of light intensity and PH on photosynthesis in Elodea densa (open access)

Effects of light intensity and PH on photosynthesis in Elodea densa

None
Date: August 1, 1975
Creator: Weber, J.A. & Gates, D.M.
System: The UNT Digital Library
Di-leptons at the Bevalac (open access)

Di-leptons at the Bevalac

Recent results on the production of di-leptons measured by the Di-Lepton-Spectrometer (DLS) collaboration are discussed. Results are reported from observations made on p /plus/ Be collisions with proton beams from 1.0 to 4.9 GeV and on Ca collisions with calcium beams of 1.0 to 2.0 GeV/A. The shape of the distributions are similar to that at higher energies. The low mass cross section appears to be explained by ..pi..-..pi.. annihilation, but detailed calculations are needed to substantiate that hypothesis. (LEN)
Date: March 1, 1988
Creator: Matis, H.S.
System: The UNT Digital Library
Analysis of the results of the Midland PRA (open access)

Analysis of the results of the Midland PRA

This paper presents the results of a limited review of the Midland PRA (MPRA), aimed at facilitating regulatory analyses and at providing insights into safety related plant failures. In particular, stress was laid on the root causes of accident sequences, particularly their failure modes, viz., hardware, human, maintenance, test, and repair. Because this information was difficult to extract in this detailed and sophisticated PRA (and in certain others) a special algorithm was developed to display the leading sequences contributing to core damage and/or to public risk in terms of the above generic failure modes. This was done in a hierarchical fashion to allow tracing the important accident sequences to the systems failures. The weighted core damage frequency (CDF) values of the sequences considered then provided a (quantitative) ranked importance listing of these failure modes, led by hardware failures (in 78%) and human factors (in 37%), etc. Multiple maintenance situations (reflecting on test and maintenance specifications) were also evaluated, but played only a small role (less than or equal to3%). Similar tabulations were also made of the (weighted) importance of the support systems (such as the electric power system, the component cooling water systems, etc.) and of the role of the …
Date: January 1, 1986
Creator: Bozoki, G. & Teichmann, T.
System: The UNT Digital Library
Relation between finite element methods and nodal methods in transport theory (open access)

Relation between finite element methods and nodal methods in transport theory

This paper examines the relationship between nodal methods and finite-element methods for solving the discrete-ordinates form of the transport equation in x-y geometry. Specifically, we will examine the relation of three finite-element schemes to the linear-linear (LL) and linear-nodal (LN) nodal schemes. The three finite-element schemes are the linear-continuous-diamond-difference (DD) scheme, the linear-discontinuous (LD) scheme, and the quadratic-discontinuous (QD) scheme. A brief derivation of the (LL) and (LN) nodal schemes is given in the third section of this paper. The approximations that cause the LL scheme to reduce to the DD, LD, and QD schemes are then indicated. An extremely simple method of deriving the finite-element schemes is then introduced.
Date: January 1, 1985
Creator: Walters, W. F.
System: The UNT Digital Library