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Characteristics of a predemonstration fusion device

Description: Low beta reactor system studies have shown that criteria necessitated by the physics lead to difficult engineering problems. The low power density produced in these systems also results in large reactors and makes the question of economic viability a serious one. It is clear that if higher pressure plasmas can be confined and operated, many of these problems could be alleviated. The incentives for high plasma density as a means of achieving higher pressures are discussed. The possible methods of achieving high density are outlined with particular attention to the high beta approaches. The requirements which are imposed on the reactor by using the flux-conserving tokamak concept are described. The characteristics of a pre-demonstration fusion device which can test the necessary aspects of such a system are developed. The plasma size required to attain ignition is found to be relatively small provided other criteria can be satisfied. These criteria are described and the technology developments and operating procedures required by them are given. The dynamic behavior and parameters of the reference system during the operating cycle are also outlined.
Date: January 1, 1976
Creator: McAlees, D. G.
Partner: UNT Libraries Government Documents Department

Damage rates of MeV Al ions in aluminum

Description: Damage rates of 5 MeV /sup 27/Al ions in Al have been measured as a function of the ion path length in Al. The technique developed for this study employed evaporated Al thin film (approximately 0.4 - 0.5 ..mu..m thick), electrical resistivity specimens, as a damage sensor and variation in ion path lengths were obtained by insertion of thin foils of Al immediately in front of the resistivity specimen. Irradiations and electrical resistance measurements were carried out below 10/sup 0/K to ''freeze in'' the displacement damage and to provide suitable conditions for precision electrical measurements. The resistance increase due to irradiation is a measure of the displacement damage resulting from ion-atom collisions in the specimen. The damage rates vary about an order of magnitude over the range of the ions and are in general agreement with calculated damage rates obtained from theory. 9 fig.
Date: November 1, 1976
Creator: Noggle, T. S.; Appleton, B. R.; Williams, J. M.; Oen, O. S.; Biggerstaff, J. A. & Iwata, T.
Partner: UNT Libraries Government Documents Department

Evaluation of EPA method 5 probe deposition and filter media efficiency. [Air sampler evaluation]

Description: In the process of development of an improved extractive stack sampler, EPA Method 5 was evaluated to quantitate probe deposition and efficiency of several glass fiber filters accepted by the method. Monodisperse fluorescing dye aerosols from 0.6 to 4.4 ..mu..m geometric diameter were generated from a vibrating orifice aerosol generator. Collection efficiencies against these aerosols were measured for MSA 1106 BH, Reeve-Angel 934AH, and Whatman GF/A and GF/C glass fiber filters at operating velocities of 5.2 and 10.3 cm/s. Efficiencies of these four filters were comparable, ranging from 99.6 to 99.8 percent against the 0.6 ..mu..m aerosol, to above 99.9 percent for aerosols larger than 1.0 ..mu..m. Probe deposition of a large (13.4 ..mu..m mass median diameter) glass bead aerosol was 94 percent, with approximately half occurring in the nozzle. Probe deposition of a 2.0 ..mu..m fly ash aerosol was 10.5 percent, again with approximately half deposited in the nozzle. Only 1.5 percent of a 1.2 ..mu..m dye aerosol deposited in the probe. These measurements emphasize the importance of consistent probe washing procedures, lower gas velocity in the nozzle, fewer bends and diameter changes, and smoother transition between probe components in the design of an improved sampler.
Date: January 1, 1977
Creator: Elder, J. C.; Tillery, M. E. & Ettinger, H. J.
Partner: UNT Libraries Government Documents Department

Structural and magnetic transitions in BaMnF/sub 4/

Description: Neutron scattering studies have been undertaken to probe the structural and magnetic transitions in BaMnF/sub 4/ occurring at T/sub c/ = 247 +- 0.5K and T/sub N/ approximately 26K respectively. Below T/sub c/ superlattice reflections are observed at incommensurate positions along the (zeta/sup 1///sub 2//sup 1///sub 2/) and (zeta00) directions of the base centered orthorhombic (A2/sub 1/am) Brillouin zone. The new reflections appear at q/sub 1/ = (+-0.392, +-0.5, +-0.5), q/sub 2/ = (+-0.216, 0, 0) and q/sub 3/ = 3(+-0.176, +-0.5, +-0.5) which bear the relationship q/sub 2/ = 2q/sub 1/ and q/sub 3/ = 3q/sub 1/. Above T/sub c/ critical scattering is observed only at the q/sub 1/ positions implying the existence of a primary order parameter with the wave vector Q/sub 1/ and either harmonics or secondary distortions with wave vectors q/sub 2/ and q/sub 3/. Below T/sub N/ magnetic superlattice peaks (q/sub 0//sup M/) were observed characteristic of the antiferromagnetic structure of the isostructural compounds BaNiF/sub 4/ and BaFeF/sub 4/. Two sets of satellite peaks q/sub 1//sup M/ and q/sub 2//sup M/ analogous to the nuclear satellites were also found. The magnon dispersion curves were measured and near neighbor exchange constants determined.
Date: January 1, 1976
Creator: Shapiro, S M; Cowley, R A; Cox, D E; Eibschutz, M & Guggenheim, H J
Partner: UNT Libraries Government Documents Department

High power rf window and waveguide component development and testing above 100 MW at X-band

Description: SLAC is committed to developing an X-band source capable of producing 100 Megawatt, 1 microsecond pulses to power the next linear collider. The first experience encountered at SLAC in the X-Band Regime above a few Megawatts was in the relativistic klystron program in cooperation with LLNL and LBL. About 280 MW had been transmitted through a variety of waveguide components but at very short pulse widths ({approximately}40 nanseconds) and very low pulse repetition rates. The likelihood of high peak power rf breakdown in most X-band components and especially rf windows increases as the rf pulse length becomes longer. Testing components at peak power levels above that at which they are expected to reliably perform is essential in a development program.
Date: August 1, 1992
Creator: Fowkes, W. R.; Callin, R. S. & Vlieks, A. E. (Stanford Linear Accelerator Center, Menlo Park, CA (United States))
Partner: UNT Libraries Government Documents Department

Comparison of an exact and moments calculation of reliability

Description: Present methods for calculating the reliability of reactor systems usually assume constant failure rates for individual components of the system. In principle, if the uncertainty in component failure rates can be expressed in terms of a probability density function, then the probability density function for the overall system reliability can be obtained. The system reliability distribution can then be used to calculate confidence bounds, for example. The probability distribution for the system reliability can also be found by an approximate method, namely the method of moments. In order to compare the exact and approximate results, a simple two element series system is modeled.
Date: January 1, 1976
Creator: Hockenbury, R. W.; Yeater, M. L.; Hawkins, J. M. & Wilkinson, J. W.
Partner: UNT Libraries Government Documents Department

Swelling studies of vanadium and vanadium-1 wt % titanium alloy using ion simulation techniques

Description: The void swelling of HPV and V-1 Ti has been investigated by irradiating the samples side by side with 3-MeV /sup 51/V/sup +/ ions to damage doses between 2.4 and 54 dpa at a temperature of 700/sup 0/C. Examination of the irradiated samples by transmission electron microscopy revealed that voids and dislocation networks had formed at 2.4 dpa in HPV and that swelling increased less than linearly with dose. In contrast, V-1 Ti showed negligible swelling even at 54 dpa. The swelling resistance of V-1 Ti to large doses is believed to be, at least in part, due to irradiation-induced precipitation.
Date: August 1, 1974
Creator: Santhanam, A. T.; Taylor, A.; Kestel, B. J. & Steves, C.
Partner: UNT Libraries Government Documents Department

CRBRP flow induced vibration program

Description: The program to assure the structural adequacy of CRBRP components during its planned 30 years of operation is described. The program includes (1) an assessment of reactor components relative to their susceptibility to FIV, (2) designing to minimize component excitation due to FIV, (3) scale model tests to measure structural response during simulated operating conditions and (4) preoperational tests. An overview of the CRBRP test program is described. Additionally, details of scale model testing of reactor internals and the steam generator is described in more detail.
Date: January 1, 1977
Creator: Novendstern, E H; Grochowski, F A; Yang, T M; Ryan, J A & Mulcahy, T M
Partner: UNT Libraries Government Documents Department

Detonation characteristics of liquid nitric oxide

Description: Liquid nitric oxide has been distilled for a number of years to alter the /sup 15/N//sup 14/N ratio. As a result of a small explosion in a distillation unit an investigation has shown that the material is a sensitive explosive. The detonation velocity for the liquid at 115/sup 0/K is estimated as 5.62 +- 0.07 mm/..mu..s and the detonation pressure as 100 kbar. The failure diameter for the liquid confined in stainless steel is between 4.6 and 3.1 mm. A high pressure reaction, but not a detonation wave, propagates at 0.7 mm.
Date: January 1, 1976
Creator: Ramsay, J. B. & Chiles, W. C.
Partner: UNT Libraries Government Documents Department

Neutron scattering study of spin waves in the amorphous ferromagnet (Fe/sub 0/ /sub 3/Ni/sub 0/ /sub 7/)/sub 0/ /sub 75/P/sub 0/ /sub 16/B/sub 0/ /sub 06/Al/sub 0/ /sub 03/

Description: The neutron inelastic scattering technique was used to measure the collective magnetic excitation spectrum in the ferromagnetic (T/sub C/ approximately 255/sup 0/K) metallic glass (Fe/sub 0/./sub 3/Ni/sub 0/./sub 7/)/sub 0/./sub 75/P/sub 0/./sub 16/B/sub 0/./sub 06/Al/sub 0/./sub 03/. In this system only the iron atoms appear to be magnetic, and the observation of relatively well-defined spin waves is striking in comparison with other amorphous systems where the spin waves rapidly broaden with decreasing iron concentration. The spin waves obey the conventional quadratic dispersion relation E/sub sw/ = DQ/sup 2/, with D = 35 MeV-A/sup 2/. Contributions from fourth and higher order terms in the dispersion relation are not in evidence for wave vectors in the region investigated (Q less than or approximately 0.25 A/sup -1/).
Date: January 1, 1976
Creator: Lynn, J. W.; Shirane, G.; Birgeneau, R. J. & Chen, H. S.
Partner: UNT Libraries Government Documents Department

Nuclear dual-purpose plants for industrial energy

Description: One of the major obstacles to extensive application of nuclear power to industrial heat is the difference between the relatively small energy requirements of individual industrial plants and the large thermal capacity of current power reactors. A practical way of overcoming this obstacle would be to operate a centrally located dual-purpose power plant that would furnish process steam to a cluster of industrial plants, in addition to generating electrical power. The present study indicates that even relatively remote industrial plants could be served by the power plant, since it might be possible to convey steam economically as much as ten miles or more. A survey of five major industries indicates a major potential market for industrial steam from large nuclear power stations.
Date: January 1, 1976
Creator: Klepper, O. H.
Partner: UNT Libraries Government Documents Department

Assessment of very high temperature reactors in process applications

Description: In April 1974, the United States Energy Research and Development Administration (ERDA) authorized General Atomic Company, General Electric Company, and Westinghouse Astronuclear Laboratory to assess the available technology for producing process heat utilizing a very high temperature nuclear reactor (VHTR). The VHTR is defined as a gas-cooled graphite-moderated reactor. Oak Ridge National Laboratory has been given a lead role in evaluating the VHTR reactor studies and potential applications of the VHTR. Process temperatures up to the 760 to 871/sup 0/C range appear to be achievable with near-term technology. The major development considerations are high temperature materials, the safety questions (especially regarding the need for an intermediate heat exchanger) and the process heat exchanger. The potential advantages of the VHTR over competing fossil energy sources are conservation of fossil fuels and reduced atmospheric impacts. Costs are developed for nuclear process heat supplied from a 3000-MW(th) VHTR. The range of cost in process applications is competitive with current fossil fuel alternatives.
Date: April 7, 1976
Creator: Jones, J. E. Jr.; Spiewak, I. & Gambill, W. R.
Partner: UNT Libraries Government Documents Department

High voltage/high resolution studies of metal and semiconductor interfaces

Description: The application of high resolution transmission electron microscopy to the study of homo- or hetero-phase interface structures requires specimens that meet stringent criteria. In some systems the necessary geometric imaging conditions are established naturally, thus greatly simplifying the analysis. This is illustrated for a diamond-hexagonal/diamond-cubic interface in deformed silicon, a {Sigma}99 tilt boundary in a pure aluminum bicrystal, and a germanium precipitate in an aluminum matrix. 13 refs., 5 figs.
Date: November 1, 1989
Creator: Westmacott, K. H. & Dahmen, U.
Partner: UNT Libraries Government Documents Department

The current status of ARAC (Atmospheric Release Advisory Capability) and its application to the Chernobyl event

Description: The Atmospheric Release Advisory Capability (ARAC) project, developed by the Lawrence Livermore National Laboratory (LLNL), provides real-time dose assessments and estimates of the extent of surface contamination that may result from an atmospheric release of radioactivity. It utilizes advanced computer-based data communication and processing systems to acquire the meteorological and source term information needed by the three-dimensional atmospheric dispersion models to derive the consequence assessments. The ARAC responded to the recent Chernobyl reactor accident in the Soviet Union by estimating the source term and the radiation dose distribution due to exposure to the radioactive cloud over Europe and the Northern Hemisphere. This analysis revealed that approximately 50% of the estimated core inventories of I-131 and Cs-137 were released. The estimated committed effective dose equivalent due to inhalation of radioactivty during cloud passage is of the order of 10 mrem within parts of Scandinavia and eastern Europe, while most of the populations within central Europe were exposed to levels ranging from 1 to 10 mrem. The amount of Cs-137 released by the Chernobyl accident far exceeds that released by previous reactor accidents, but is only about 6% of the Cs-137 produced by the atmospheric weapon testing programs. 9 refs., 4 figs., 2 tabs.
Date: October 1, 1986
Creator: Gudiksen, P. H.; Sullivan, T. J. & Harvey, T. F.
Partner: UNT Libraries Government Documents Department

Systems Integration Operations/Logistics Model (SOLMOD)

Description: SOLMOD is a discrete event simulation model written in FORTRAN 77 and operates in a VAX or PC environment. The model emulates the movement and interaction of equipment and radioactive waste as it is processed through the FWMS. SOLMOD can be used to measure the impacts of different operating schedules and rules, system configurations, reliability, availability, maintainability (RAM) considerations, and equipment and other resource availabilities on the performance of processes comprising the FWMS and how these factors combine to determine overall system performance. Model outputs are a series of measurements of the amount and characteristics of waste at selected points in the FWMS and the utilization of resources needed to transport and process the waste. The model results may be reported on a yearly, monthly, weekly, or daily basis to facilitate analysis. 3 refs., 3 figs., 2 tabs.
Date: January 1, 1990
Creator: Vogel, L. W. (Science Applications International Corp., McLean, VA (USA)) & Joy, D. S. (Oak Ridge National Lab., TN (USA))
Partner: UNT Libraries Government Documents Department

Contaminant effects in solid oxide fuel cells

Description: Two full scale (50-cm length) SOFCS, each representative of generator cells in the field, were electrically connected in series; then operated at 1000{degrees}C and 350 mA/cm{sup 2}. An initial run of approximately 150 hours served to establish baseline performance in 89% H{sub 2}, 11% H{sub 2}0 fuel at 85% fuel utilization and 4 stoichs, air. Then, for approximately 200 hours, a similar base-line was established for operation in simulated coal gas fuel. Finally, the fuel impurity components were sequentially added. The cumulative effect on performance as shown in Table 3. These data reveal no strong association of cell resistance with cell performance change in the cases of NH{sub 3} and HCI. When H{sub 2}S is added, resistance increases account for a minor part of the 0.06V decline observed for each cell over the first 24 hours. However, cell resistances thereafter change linearly, along with linearly declining voltages. In this latter phase, resistance accounts for a major part of each observed cell voltage decline. The same two SOFCs were subsequently continued in operation, but at a moderately higher temperature, 1025{degrees}C. As Figure 2 demonstrates, No. 1 cell tended to decline more slowly, and No. 2 cell continued to decline at the same rate as before, when it was operating at 1OOO{degrees}C. Later operation, without impurities, at 1025{degrees}C for 450 hours served to improve performance and stabilize the cells. When operation at 1000{degrees}C resumed, the cell resistance trend lines returned to approximately the original R vs. t slopes observed during 0-500 hours on test, signifying cessation of impurity-related voltage degradation.
Date: January 1, 1992
Creator: Maskalisk, N. J. & Ray, E. R.
Partner: UNT Libraries Government Documents Department

Effect of stress relief parameters on the mechanical properties of pressure vessel steels and weldments

Description: Post weld heat treatments of thick-section A533B steel for nuclear pressure vessels are discussed with reference to the ASME code. The discussion is in the form of a lecture and summarized by noting that the ASME code, in particular Section III, Division 1, imposes a post weld heat treatment requirement on pressure vessels fabricated from low alloy high strength steels. The Code permits a holding temperature range, the high side of which could result in poorer toughness properties. Long times in excess of 100 hours and/or high temperatures, 649/sup 0/C can result in an increase in the NDT and a decrease in the upper shelf energy.
Date: January 1, 1976
Creator: Canonico, D. A. & Stelzman, W. J.
Partner: UNT Libraries Government Documents Department

Interactive nuclear plant analyzer for VVER-440 reactor

Description: This document discusses an interactive nuclear plant analyzer (NPA) which has been developed for a VVER-440, Model 213 reactor for use in the training of plant personnel, the development and verification of plant operating procedures, and in the analysis of various anticipated operational occurrences and accident scenarios. This NPA is operational on an IBM RISC-6000 workstation and utilizes the RELAP5/MOD2 computer code for the calculation of the VVER-440 reactor response to the interactive commands initiated by the NPA operator.
Date: May 1, 1992
Creator: Shier, W.; Horak, W. & Kennett, R.
Partner: UNT Libraries Government Documents Department

New particles and interactions

Description: The Working Group on New Particles and Interactions met as a whole at the beginning and at the end of the Workshop. However, much of what was accomplished was done in five subgroups. These were devoted to: (1) new quarks and leptons; (2) technicolor; (3) supersymmetry; (4) rare decays and CP; and (5) substructure of quarks and leptons. Other aspects of new particles, e.g., Higgs, W', Z', fell to the Electroweak Working Group to consider. The central question of this Workshop of comparing anti pp (with L = 10/sup 32//cm/sup 2/-sec) with pp (with L = 10/sup 33//cm/sup 2/-sec) colliders carried through to all these subgroups. In addition there were several other aspects of hadron colliders which were considered: what does an increase in ..sqrt..s gain in cross section and resultant sensitivity to new physics versus an increase in luminosity; will polarized beams or the use of asymmetries be essential in finding new interactions; where and at what level do rate limitations due to triggering or detection systems play a role; and how and where will the detection of particles with short, but detectable, lifetimes be important. 25 references.
Date: April 1, 1984
Creator: Gilman, F. J. & Grannis, P. D.
Partner: UNT Libraries Government Documents Department

Identification of neutron noise sources in a boiling water reactor

Description: Measurements were made at units 2 and 3 of the Browns Ferry Nuclear Power Plant in order to characterize the noise signatures of the neutron and process signals and to determine the usefulness of such signatures for anomaly detection in BWR-4s. Previous measurements and theoretical analyses of BWR noise by others were concerned with the determination of steam velocity and void fraction (using the local component of neutron noise) and with the sources of global noise. The work described is under a five-part program to develop a complete and systematic analysis and representation of BWR neutron and process noise through complementary measurements and stochastic model developments. The parts are: (1) recording as many neutron detector and process noise signals as are available in a BWR-4; (2) reducing these data to noise signatures in order to perform an empirical analysis of these signatures, and documenting the relationships between the signals from spatially separated neutron detectors and between neutron and process variables; (3) developing spatially dependent neutronic models coupled with thermal-hydraulic models to aid in interpreting the observed relationships among the measured noise signatures, (4) comparing measured noise signatures with model predictions to obtain additional insight into BWR-4 dynamic behavior and to validate the models; and (5) using these models to predict the sensitivity of noise monitoring for detection, surveillance, and diagnosis of postulated in-core anomalies in BWRs. The paper describes the procedures used to obtain the noise recordings and presents initial empirical analysis and observations pertaining to the noise signatures and the relationships between several noise variables in the 0.01- to 1-Hz range. The mathematical models have not been developed sufficiently to report theoretical results or to compare measured spectra with model predictions at this time.
Date: January 1, 1977
Creator: Sides, W. H. Jr.; Mathis, M. V. & Smith, C. M.
Partner: UNT Libraries Government Documents Department

Status of the Fermilab Energy Doubler/Saver project

Description: The possibility of building a ring of superconducting magnets was considered very early in the design of the Fermilab main accelerator. It was concluded that the technology of superconducting magnets was not at that time, sufficiently advanced. Therefore, the main ring was designed and built with conventional magnets. However, space was left in the main-ring tunnel for a future ring of superconducting magnets. The Energy Doubler/Saver (ED/S) was initiated in 1972 as a project to build a ring of superconducting magnets with the objective of dramatically increasing the research potential of the Fermilab accelerators. This was to be accomplished at a moderate cost and in such a manner as to make possible a significant saving of electrical energy. A description is given of the evolution of this program as well as give a status report of the Ed/S research and development program.
Date: January 1, 1977
Partner: UNT Libraries Government Documents Department