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Further considerations of critical heat flux in saturated pool boiling during power transients (open access)

Further considerations of critical heat flux in saturated pool boiling during power transients

In this paper, we further evaluate our previously postulated transient CHF model. First, we verify the steady-state CHF model on which the transient model is based by using recent macrolayer-thickness data. We also include the effect of thermal storage in the heater that we previously neglected. The use of a simplified approach in the prediction of the instantaneous surface heat flux for given pwoer generation rates considerably improves the predictive capability of the transient critical heat-flux (CHF) model. Finally, we discuss the statistical vapor mass behavior during transient boiling and its effect on the transient CHF model. We show that the data scatter within a small range may be partially explained through such an approach.
Date: January 1, 1988
Creator: Pasamehmetoglu, K.O. & Nelson, R.A.
Object Type: Article
System: The UNT Digital Library
Integral fast reactor safety features (open access)

Integral fast reactor safety features

The Integral Fast Reactor (IFR) is an advanced liquid-metal-cooled reactor concept being developed at Argonne National Laboratory. The two major goals of the IFR development effort are improved economics and enhanced safety. In addition to liquid metal cooling, the principal design features that distinguish the IFR are: (1) a pool-type primary system, (2) an advanced ternary alloy metallic fuel, and (3) an integral fuel cycle with on-site fuel reprocessing and fabrication. This paper focuses on the technical aspects of the improved safety margins available in the IFR concept. This increased level of safety is made possible by (1) the liquid metal (sodium) coolant and pool-type primary system layout, which together facilitate passive decay heat removal, and (2) a sodium-bonded metallic fuel pin design with thermal and neutronic properties that provide passive core responses which control and mitigate the consequences of reactor accidents.
Date: January 1, 1988
Creator: Cahalan, J. E.; Kramer, J. M.; Marchaterre, J. F.; Mueller, C. J.; Pedersen, D. R.; Sevy, R. H. et al.
Object Type: Article
System: The UNT Digital Library
New newtron time-of-flight (NTOF) facilities at the Brookhaven 200-MeV Linac (open access)

New newtron time-of-flight (NTOF) facilities at the Brookhaven 200-MeV Linac

The installation of a new beam chopper and radio-frequency quadrupole (RFQ) preinjector (750 keV) at the Brookhaven National Laboratory (BNL) 200-MeV Linac will enable single micropulse selection (pulse width <1 ns) with periods ranging from 400 ns to 10 ..mu..s. The standard micropulse intensity is 1.2 X 10/sup 9/ p..mu.. pulse with dc-average beam currents of 50 nA-1 ..mu..A routinely available. The NTOF facilities consists of 30-100 meter flight paths at angles of 0, 12, 30, 45, 90, and 135/degree/. Lower energies of 93, 117, 139, 161, and 181 MeV are also available as well as polarized beams at much reduced intensities. The present paper describes the new facilities, and the capabilities of future improvements and upgrades, for use in the BNL intermediate energy (p,n) experimental program. 7 refs., 2 figs., 1 tab.
Date: January 1, 1988
Creator: Ward, T.E.; Alessi, J.; Brennan, J.; Grand, P.; Lankshear, R.; Snead, C.L. et al.
Object Type: Article
System: The UNT Digital Library
The electronic structure of condensed molecular systems (open access)

The electronic structure of condensed molecular systems

We have reviewed some of the basic properties of the electronic structure of condensed molecular systems. For the rare-gas solids, we concentrated our discussion on changes in the ground- and excited-state crystal-atomic wave functions as calculated with an approximate theoretical method. Compression of these wave functions leads to a softening of the equation of state at high densities, which seems to account for much of the total many-body effects. This compression is a true many-body effect and cannot be easily decomposable into a sum of 3-body and higher terms. We reviewed the electronic properties of four molecular systems, each manifesting different behavior at high densities. Because of a general lack of theory of the electronic structure of molecular solids, we restricted ourselves to a descriptive account. Solid oxygen, for instance, seems to exhibit the beginnings of covalent bonding between the ..pi..* orbitals on adjacent molecules in its epsilon phase. It was a combination of optical-absorption data and infrared and Raman spectroscopy that led to these conclusions. Iodine is unique in that it becomes metallic as a molecular crystal at pressures easily obtainable experimentally. It is interesting that the x-ray data, which indicates a transition to a monatomic lattice at 21 …
Date: January 1, 1988
Creator: LeSar, R.A.
Object Type: Article
System: The UNT Digital Library
Profile correction to electron temperature and enhancement factor in soft x-ray pulse-height-analysis measurements in tokamaks (open access)

Profile correction to electron temperature and enhancement factor in soft x-ray pulse-height-analysis measurements in tokamaks

Because soft x-ray pulse-height-analysis (PHA) spectra contain chordal information, the electron temperature and the radiation intensity (enhancement factor) measurements do not represent the local values. Assuming that the profile Ansatz for the electron temperature and density is of the form n/sub eo/(1-(ra)/sup 2/)/sup ..cap alpha../ and kT/sub eo/(1--(ra)/sup 2/)/sup ..beta../, we obtain the correction factors for the electron temperature and the enhancement factor as a function of the profile coefficients ..cap alpha.. and ..beta.. and the energy at which the evaluation was made. The corrected values of the temperature are typically between 1 to 10% higher than the values derived from the raw chordal spectra. We also correct the measured radiation intensity for the profile effects. Finally, the spectrum distortion due to pulse pile-up effects is evaluated. A set of curves is given from which the distortion of the spectrum can be obtained, if the electron temperature, the Be or Al filter thickness, and the electronic parameters of the acquisition system are known. 7 refs., 23 figs.
Date: April 1, 1988
Creator: Sesnic, S.; Diesso, M.; Hill, K.; Holland, A. & Pohl, F.
Object Type: Report
System: The UNT Digital Library
Use of fiber optic equipment for security (open access)

Use of fiber optic equipment for security

This paper discusses the many applications of fiber optics equipment. (LSP)
Date: January 1, 1988
Creator: Schalm, R.W.
Object Type: Article
System: The UNT Digital Library
Isotopically selective, Doppler-free, saturation spectroscopy of lutetium isotopes via resonance ionization mass spectrometry (open access)

Isotopically selective, Doppler-free, saturation spectroscopy of lutetium isotopes via resonance ionization mass spectrometry

A new technique utilizing RIMS to obtain very high resolution atomic spectra with isotopic selectivity has been demonstrated. This technique allows the precise determination of HF splitting constants, limited only by the transition's natural linewidth. In addition, it is also feasible with this technique to accurately determine atomic isotope shifts. The exact determination of HF component line positions provides data for isotopically selective ionization which, in turn, will increase RIMS' dynamic range. Future work includes the incorporation of a /open quotes/vibrating/close quotes/ mirror and the study of rarer isotopes, i.e., /sup 174/Lu, /sup 173/Lu, /sup 172/Lu, /sup 171/Lu, and possibly, /sup 170/Lu. 13 refs., 3 figs.
Date: January 1, 1988
Creator: Fearey, B. L.; Parent, D. C.; Keller, R. A. & Miller, C. M.
Object Type: Article
System: The UNT Digital Library
Rf cavity primer for cyclic proton accelerators (open access)

Rf cavity primer for cyclic proton accelerators

The purpose of this note is to describe the electrical and mechanical properites of particle accelerator rf cavities in a manner which will be useful to physics and engineering graduates entering the accelerator field. The discussion will be limited to proton (or antiproton) synchrotron accelerators or storage rings operating roughly in the range of 20 to 200 MHz. The very high gradient, fixed frequency UHF or microwave devices appropriate for electron machines and the somewhat lower frequency and broader bandwidth devices required for heavy ion accelerators are discussed extensively in other papers in this series. While it is common pratice to employ field calculation programs such as SUPERFISH, URMEL, or MAFIA as design aids in the development of rf cavities, we attempt here to elucidate various of the design parameters commonly dealt with in proton machines through the use of simple standing wave coaxial resonator expressions. In so doing, we treat only standing wave structures. Although low-impedance, moderately broad pass-band travelling wave accelerating systems are used in the CERN SPS, such systems are more commonly found in linacs, and they have not been used widely in large cyclic accelerators. Two appendices providing useful supporting material regarding relativistic particle dynamics and …
Date: April 1, 1988
Creator: Griffin, J.E.
Object Type: Article
System: The UNT Digital Library
Uranium hexafluoride: Safe handling, processing, and transporting: Conference proceedings (open access)

Uranium hexafluoride: Safe handling, processing, and transporting: Conference proceedings

This conference seeks to provide a forum for the exchange of information and ideas of the safety aspects and technical issue related to the handling of uranium hexafluoride. By allowing operators, engineers, scientists, managers, educators, and others to meet and share experiences of mutual concern, the conference is also intended to provide the participants with a more complete knowledge of technical and operational issues. The topics for the papers in the proceedings are widely varied and include the results of chemical, metallurgical, mechanical, thermal, and analytical investigations, as well as the developed philosophies of operational, managerial, and regulatory guidelines. Papers have been entered individually into EDB and ERA. (LTN)
Date: January 1, 1988
Creator: Strunk, W.D. & Thornton, S.G. (eds.)
Object Type: Article
System: The UNT Digital Library
SDI: Myth or reality (open access)

SDI: Myth or reality

This report reviews previous attempt to develop strategic defenses, the technologies currently under consideration, their main unknowns, and their likely performance relative to evolving threats. 28 refs.
Date: January 1, 1988
Creator: Canavan, G.H.
Object Type: Article
System: The UNT Digital Library
Experience with the NEG (nonevaporable getter) strips at the Brookhaven heavy ion transport line (open access)

Experience with the NEG (nonevaporable getter) strips at the Brookhaven heavy ion transport line

The AGS and the Tandem Van de Graaff, two valuable physics assets, are now jointed together by a transport line of 700 m in length. This line allows heavy ions from the Tandem, up to a fully striped silicon (M = 28) to be injected into the AGS and accelerated to energies of approximately 15 GeVamu. New areas of physics research at very high nuclear densities can now be studied using some of the extensive experimental facilities already existing at the AGS. With the addition of a booster synchrotron between the Tandem and the AGS, all heavier ions up to gold can also be accelerated. To minimize the beam loss due to charge exchange between the partially stripped heaviest ions (i.e. Au + 33 at 1 MeVamu) and the residual gas molecules, a vacuum of 10 /sup /minus/8/ Torr is required for this transport line. To achieve this vacuum, we have opted to use the combination of small ion pumps (20 1s diode type) and simple geometry was implemented which offers low cost (<$200m), easy installation and maintenance. Pressures of 10 /sup /minus/10/ and low 10 /sup /minus/9/ Torr have been maintained over the last two years following the initial …
Date: January 1, 1988
Creator: Hseuh, H. C.; Benjamin, J.; Stattel, P.; Feigenbaum, I. & Manni, M.
Object Type: Article
System: The UNT Digital Library
Nonlinear gyrokinetic theory for finite-BETA plasmas (open access)

Nonlinear gyrokinetic theory for finite-BETA plasmas

A self-consistent and energy-conserving set of nonlinear gyrokinetic equations, consisting of the averaged Vlasov and Maxwell's equations for finite-..beta.. plasmas, is derived. The method utilized in the present investigation is based on the Hamiltonian formalism and Lie transformation. The resulting formation is valid for arbitrary values of k/perpendicular//rho//sub i/ and, therefore, is most suitable for studying linear and nonlinear evolution of microinstabilities in tokamak plasmas as well as other areas of plasma physics where the finite Larmor radius effects are important. Because the underlying Hamiltonian structure is preserved in the present formalism, these equations are directly applicable to numerical studies based on the existing gyrokinetic particle simulation techniques. 31 refs.
Date: February 1, 1988
Creator: Hahm, T. S.; Lee, W. W. & Brizard, A.
Object Type: Report
System: The UNT Digital Library
Towards an advanced hadron facility at Los Alamos (open access)

Towards an advanced hadron facility at Los Alamos

In the 1987 workshop, it was pointed out that activation of the accelerator is a serious problem. At this workshop, it was suggested that a new type of slow extraction system is needed to reduce the activation. We report on the response to this need. The Los Alamos plan is reviewed including as elements the long lead-time R and D in preparation for a 1993 construction start, a menu of accelerator designs, improved losses at injection and extraction time, active participation in the development of PSR, and accelerated hardware R and D program, and close collaboration with TRIUMF. We review progress on magnets and power supplies, on ceramic vacuum chambers, and on ferrite-turned rf systems. We report on the plan for a joint TRIUMF-Los Alamos main-ring cavity to be tested in PSR in 1989. The problem of beam losses is discussed in detail and a recommendation for a design procedure for the injection system is made. This recommendation includes taking account of single Coulomb scattering, a painting scheme for minimizing foil hits, and a collimator and dump system for containing the expected spills. The slow extraction problem is reviewed and progress on an improved design is discussed. The problem of …
Date: January 1, 1988
Creator: Thiessen, H.A.
Object Type: Article
System: The UNT Digital Library
Biological solutions to waste management (open access)

Biological solutions to waste management

The purpose of this program is to develop low-cost processes for the removal of toxic metals from geothermal residual brines. Processes and methodologies are also being developed for the utilization of detoxified residues. Laboratory work at Brookhaven National Laboratory (BNL) has shown that bioleaching is an efficient method for the removal of toxic metals from residual brine sludges. Samples of geothermal brine residues, supplied by the industry, containing elevated concentrations of heavy metals were treated with cultures of several strains of acidophilic bacteria Thiobacillus thioxidans and Thiobacillus ferrooxidans, selected from the BNL collection. The effect of different experimental conditions on the rate of toxic metal removal has been investigated. Based on the experimental results obtained, a detoxification process for geothermal brine residues has been explored. A preliminary technical feasibility study indicates that for a typical 50 MW plant, a large-scale technically feasible process can be developed. 6 refs., 1 fig., 2 tabs.
Date: January 1, 1988
Creator: Premuzic, E. T.; Lin, Mow & Kukacka, L.
Object Type: Article
System: The UNT Digital Library
Dominant lethal study in CD-1 mice following inhalation exposure to 1,3-butadiene: Final technical report (open access)

Dominant lethal study in CD-1 mice following inhalation exposure to 1,3-butadiene: Final technical report

The effects of whole-body inhalation exposures to 1,3-butadiene on the reproductive system was evaluated. The results of dominant lethality in CD-1 male mice that were exposed to 1,3-butadiene are described. Subsequent to exposure, males were mated with two unexposed females. Mating was continued for 8 weeks with replacement of two females each week. Gravid uteri were removed, and the total number, position and status of implantations were determined. The mice were weighed prior to exposure and at 0, 1, 2, 3, 4, 5, 6, 7, and 8 weeks after exposure and at sacrifice. The animals were observed for mortality, morbidity and signs of toxicity throughout the study. 19 refs., 5 figs., 9 tabs.
Date: April 1, 1988
Creator: Hackett, P. L.; Mast, T. J.; Brown, M. G.; Clark, M. L.; Evanoff, J. J.; Rowe, S. E. et al.
Object Type: Report
System: The UNT Digital Library
Analysis of plasma coupling with the prototype DIII-D ICRF antenna (open access)

Analysis of plasma coupling with the prototype DIII-D ICRF antenna

Coupling to plasma in the H-mode is essential to the success of future ignited machines such as CIT. To ascertain voltage and current requirements for high-power second harmonic heating (2 MW in a 35- by 50-cm port), coupling to the DIII-D tokamak with a prototype compact loop antenna has been measured. The results show good loading for L-mode and limiter plasmas, but coupling 2 MW to an H-mode plasma demands voltages and currents near the limit of present technology. We report the technological analysis and progress that allow coupling of these power densities. 5 refs., 4 figs.
Date: January 1, 1988
Creator: Ryan, P.M.; Hoffman, D.J.; Bigelow, T.S.; Baity, F.W.; Gardner, W.L.; Mayberry, M.J. et al.
Object Type: Article
System: The UNT Digital Library
Challenge problems focusing on equality and combinatory logic: Evaluating automated theorem-proving programs (open access)

Challenge problems focusing on equality and combinatory logic: Evaluating automated theorem-proving programs

In this paper, we offer a set of problems for evaluating the power of automated theorem-proving programs and the potential of new ideas. Since the problems published in the proceedings of the first CADE conference proved to be so useful, and since researchers are now far more disposed to implementing and testing their ideas, a new set of problems to complement those that have been widely studied is in order. In general, the new problems provide a far greater challenge for an automated theorem-proving program than those in the first set do. Indeed, to our knowledge, five of the six problems we propose for study have never been proved with a theorem-proving program. For each problem, we give a set of statements that can easily be translated into a standard set of clauses. We also state each problem in its mathematical and logical form. In many cases, we also provide a proof of the theorem from which a problem is taken so that one can measure a program's progress in its attempt to solve the problem. Two of the theorems we discuss are of especial interest in that they answer questions that had been open concerning the constructibility of two …
Date: January 1, 1988
Creator: Wos, L. & McCune, W.
Object Type: Article
System: The UNT Digital Library
Consolidated Incineration Facility model videotape (open access)

Consolidated Incineration Facility model videotape

A Consolidated Incineration Facility (CIF) is in final design for construction at the Savannah River Plant in Aiken, South Carolina. The CIF will detoxify and volume reduce combustible radioactive, hazardous and mixed waste. A study model was constructed during scope development for project authorization to assist with equipment layout and insure sufficient maintenance access. To facilitate the Department of Energy Validation process, a videotape of the model was developed. This ten minute videotape includes general information about the incineration process and a tour of the study model with a discussion of activities in each area. The videotape will be shown and the current status and schedule for the CIF presented.
Date: January 1, 1988
Creator: Krolewski, J F & Augsburger, S T
Object Type: Article
System: The UNT Digital Library
The P-Factor and Atomic Mass Systematics: Application to Medium Mass Nuclei (open access)

The P-Factor and Atomic Mass Systematics: Application to Medium Mass Nuclei

The P formalism was applied to atomic mass systematics for medium and heavy nuclei. The P-factor linearizes the structure-dependent part of the nuclear mass in those regions which are free from subshell effects indicating that the attractive quadrupole p-n force plays an important role in determining the binding of valence nucleons. Where marked non-linearities occur, the P-factor provides a means for recognizing subshell closures and/or other structural features not embodied in the simple assumptions of abrupt shell or subshell changes. These are thought to be regions where the monopole part of the p-n interaction is highly orbit dependent and alters the underlying single-particle structure as a function of A, N or Z. Finally, in those regions where the systematics are smooth and subshells are absent, the P-factor provides a means for predicting masses of some nuclei far-from-stability by interpolation rather than by extrapolation. 5 figs.
Date: January 1, 1988
Creator: Brenner, D. S.; Haustein, P. E. & Casten, R. F.
Object Type: Article
System: The UNT Digital Library
Anomalous rf magnetoresistance in copper at 4/degree/K (open access)

Anomalous rf magnetoresistance in copper at 4/degree/K

We have measured the effect of a magnetic field on the surface resistance of polycrystalline Cu at f = 1.2 GHz and at 4.4/degree/K; under these conditions the surface resistance is well into the anomalous skin effect regime but has not reached its limiting value. We find that the transverse and longitudinal magnetoresistance are an order of magnitude smaller than the DC magnetoresistance and depend quadratically on the field. At low fields we observe a decrease in surface resistance with increasing field which can be interpreted as a size effect of the TF surface current. 17 refs., 4 figs., 1 tab.
Date: March 1, 1988
Creator: Halama, H. J.; Prodell, A. G.; Rogers, J. T.; De Panfilis, S.; Melissinos, A. C.; Moskowitz, B. E. et al.
Object Type: Report
System: The UNT Digital Library
Development of nuclear models for higher energy calculations (open access)

Development of nuclear models for higher energy calculations

Two nuclear models for higher energy calculations have been developed in the regions of high and low energy transfer, respectively. In the former, a relativistic hybrid-type preequilibrium model is compared with data ranging from 60 to 800 MeV. Also, the GNASH exciton preequilibrium-model code with higher energy improvements is compared with data at 200 and 318 MeV. In the region of low energy transfer, nucleon-nucleus scattering is predominately a direct reaction involving quasi-elastic collisions with one or more target nucleons. We discuss various aspects of quasi-elastic scattering which are important in understanding features of cross sections and spin observables. These include (1) contributions from multi-step processes; (2) damping of the continuum response from 2p-2h excitations; (3) the ''optimal'' choice of frame in which to evaluate the nucleon-nucleon amplitudes; and (4) the effect of optical and spin-orbit distortions, which are included in a model based on the RPA the DWIA and the eikonal approximation. 33 refs., 15 figs.
Date: January 1, 1988
Creator: Bozoian, M.; Siciliano, E. R. & Smith, R. D.
Object Type: Article
System: The UNT Digital Library
Health, Safety, and Environment Division: Annual progress report 1987 (open access)

Health, Safety, and Environment Division: Annual progress report 1987

The primary responsibility of the Health, Safety, and Environment (HSE) Division at the Los Alamos National Laboratory is to provide comprehensive occupational health and safety programs, waste processing, and environment protection. These activities are designed to protect the worker, the public, and the environment. Many disciplines are required to meet the responsibilities, including radiation protection, industrial hygiene, safety, occupational medicine, environmental science, epidemiology, and waste management. New and challenging health and safety problems arise occasionally from the diverse research and development work of the Laboratory. Research programs in HSE Division often stem from these applied needs. These programs continue but are also extended, as needed to study specific problems for the Department of Energy and to help develop better occupational health and safety practices.
Date: April 1, 1988
Creator: Rosenthal, M.A. (comp.)
Object Type: Report
System: The UNT Digital Library
Insertion device and beam line plans for the Advanced Photon Source: A report and recommendations by the Insertion Device and Beam Line Planning Committee (open access)

Insertion device and beam line plans for the Advanced Photon Source: A report and recommendations by the Insertion Device and Beam Line Planning Committee

In the 7-GeV Advanced Photon Source (APS) Conceptual Design Report (CDR), fifteen complete experimental beam lines were specified in order to establish a representative technical and cost base for the components involved. In order to optimize the composition of the insertion devices and the beam line, these funds are considered a ''Trust Fund.'' The present report evaluates the optimization for the distribution of these funds so that the short- and long-term research programs will be most productive, making the facility more attractive from the user's point of view. It is recommended that part of the ''Trust Fund'' be used for the construction of the insertion devices, the front-end components, and the first-optics, minimizing the cost to potential users of completing a beam line. In addition, the possibility of cost savings resulting from replication and standardization of high multiplicity components (such as IDs, front ends, and first-optics instrumentation) is addressed. 2 refs., 5 tabs.
Date: February 1, 1988
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Optical imaging diagnostics for fusion plasmas (open access)

Optical imaging diagnostics for fusion plasmas

Imaging diagnostics are used for spatially/emdash/and temporally/emdash/resolved quantitative measurements of plasma properties such as the ionization particle source, particle and energy loss, and impurity radiation in magnetically confined fusion plasmas. Diagnostics equipped with multi-element solid-state detectors (often with image intensifiers) are well suited to the environment of large fusion machines with high magnetic field and x-ray and neutron fluxes. We have both conventional (16msframe) and highspeed video cameras to measure neutral deuterium H/sub ..cap alpha../ (6563 /angstrom/) emissions from fusion plasmas. Continuous high-speed measurements are made with video cameras operating at 0.1 to 0.5 msframe; gated cameras provide snapshots of 10 to 100 ..mu..s during each 16-ms video frame. Digital data acquisition and absolute intensity calibrations of the cameras enable detailed quantitative source measurements: these are extremely important in determining the particle balance of the plasma. In a liner confinement device, radial transport can be determined from the total particle balance. In a toroidal confinement device, the details of particle recycling can be determined. Optical imaging in other regions of the spectrum are also important, particularly for the diverter region of large tokamaks. Absolutely calibrated infrared cameras have been used to image to temperature changes in the wall and thereby …
Date: April 1, 1988
Creator: Allen, S.L.
Object Type: Article
System: The UNT Digital Library