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Fast imaging applications in the Nuclear Test Program (open access)

Fast imaging applications in the Nuclear Test Program

Applications of fast imaging employ both streak cameras and fast framing techniques. Image intensifier tubes are gated to provide fast two-dimensional shutters of 2 to 3 ns duration with shatter ratios of greater than 10/sup 6/ and resolution greater than 10/sup 4/ pixels. Shutters of less than 1 ns have been achieved with experimental tubes. Characterization data demonstrate the importance of tube and pulser design. Streak cameras are used to simultaneously record temporal and intensity information from up to 200 spatial points. Streak cameras are combined with remote readout for downhole uses and are coupled to fiber optic cables for uphole uses. Optical wavelength multiplexing is being studied as a means of compressing additional image data onto optical fibers. Performance data demonstrate trade-offs between image resolution and system sensitivity.
Date: October 14, 1983
Creator: Lear, R.
System: The UNT Digital Library
3D field calculation of the GEM prototype magnet and comparison with measurements (open access)

3D field calculation of the GEM prototype magnet and comparison with measurements

The proposed 4 GeV Electron Microtron (GEM) is designed to fill the existing buildings left vacant by the demise of the Zero Gradient Synchrotron (ZGS) accelerator. One of the six large dipole magnets is shown as well as the first 10 electron orbits. A 3-orbit prototype magnet has been built. The stepped edge of the magnet is to keep the beam exiting perpendicular to the pole. The end guards that wrap around the main coils are joined together by the 3 shield plates. The auxiliary coils are needed to keep the end guards and shield plates from saturating. A 0.3 cm Purcell filter air gap exists between the pole and the yoke. Can anyone question this being a truly three-dimensional magnetostatic problem. The computer program TOSCA, developed at the Rutherford Appleton Laboratory by the Computing Applications Group, was used to calculate this magnet and the results have been compared with measurements.
Date: October 28, 1983
Creator: Lari, R.J.
System: The UNT Digital Library
Improved information processing and dissemination through the introduction of new technology (open access)

Improved information processing and dissemination through the introduction of new technology

This paper discusses the following topic on information technology: technology signals a liberation; application of information technology; optical character recognition; optical memories; and planning considerations and the future.
Date: October 1, 1983
Creator: Spath, C E & Marsh, Jr, F E
System: The UNT Digital Library
Release of volatile fission products from UO/sub 2/ (open access)

Release of volatile fission products from UO/sub 2/

In our experiments, post-irradiation anneal of lightly-irradiated UO/sub 2/ was used to measure the release kinetics of the volatile fission products Xe, I, and Te. The fraction of a particular fission product retained in a specimen was measured by gamma-ray spectroscopy before and following an anneal.
Date: October 1, 1983
Creator: Prussin, S.G.; Olander, D.R.; Goubeault, P. & Bayen, D.
System: The UNT Digital Library
Review of the 3rd biennial conference on real-time computer applications in nuclear and particle physics (open access)

Review of the 3rd biennial conference on real-time computer applications in nuclear and particle physics

The topics presented at Berkeley centered on computer technologies and architecture as they effect the data-acquisition and data reduction process. Data-acquisition hardware activities were well represented with discussions of CAMAC, FASTBUS, and specialized hardware for data sorting, pipelined operations, and parallel processing. Vendors of CAMAC and FASTBUS products were present to demonstrate their systems and track new research developments and directions.
Date: October 1, 1983
Creator: O'Brien, D.W.
System: The UNT Digital Library
System for intelligent teleoperation research (open access)

System for intelligent teleoperation research

The Automation Technology Branch of NASA Langley Research Center is developing a research capability in the field of artificial intelligence, particularly as applicable in teleoperator/robotics development for remote space operations. As a testbed for experimentation in these areas, a system concept has been developed and is being implemented. This system, termed DAISIE (Distributed Artificially Intelligent System for Interacting with the Environment), interfaces the key processes of perception, reasoning, and manipulation by linking hardware sensors and manipulators to a modular artificial intelligence (AI) software system in a hierarchical control structure. Verification experiments have been performed: one experiment used a blocksworld database and planner embedded in the DAISIE system to intelligently manipulate a simple physical environment; the other experiment implemented a joint-space collision avoidance algorithm. Continued system development is planned.
Date: October 25, 1983
Creator: Orlando, N.E.
System: The UNT Digital Library
Process, product, and waste-stream monitoring with fiber optics (open access)

Process, product, and waste-stream monitoring with fiber optics

Fiber optic technology, motivated by communications and defense applications, has advanced significantly the past ten years. In particular, advances have been made in visible radiation transmission efficiency with concurrent reductions in fiber size, weight, and cost. Researchers at the Lawrence Livermore National Laboratory (LLNL) coupled these advances in fiber optic technology with analytical fluorescence analysis to establish a new technology - remote fiber fluorimetry (RFF). Laser-based RFF offers the potential to measure and monitor from one central and remote laboratory, on-line, and in near real time, trace (ppM) to substantial (g/L) concentrations of selected chemical species in typical process, product, and waste streams. The fluorimeter consists of a fluorescence or Raman spectrometer; unique coupling optics that separates input excitation (laser) radiation from return (fluorescence) radiation; a fiber optic cable; and an optrode - a terminal that interfaces the fiber to the measurement point, which is designed to respond quantitatively to a particular chemical species. At LLNL, research is underway into optrodes that measure pressure, temperature, and pH and those that detect and quantify various actinides, sulfates, inorganic chloride, hydrogen sulfide, aldehydes, and alcohols.
Date: October 10, 1983
Creator: Milanovich, F.P. & Hirschfeld, T.
System: The UNT Digital Library
Delta-Nucleus Dynamics: Proceedings of Symposium (open access)

Delta-Nucleus Dynamics: Proceedings of Symposium

The appreciation of the role in nuclear physics of the first excited state of the nucleon, the delta ..delta..(1232), has grown rapidly in the past decade. The delta resonance dominates nuclear reactions induced by intermediate energy pions, nucleons, and electromagnetic probes. It is also the most important non-nucleonic degree of freedom needed to resolve many fundamental problems encountered in the study of low-energy nuclear phenomena. Clearly, a new phase of nuclear physics has emerged and conventional thinking must be extended to account for this new dimension of nuclear dynamics. The most challenging problem we are facing is how a unified theory can be developed to describe ..delta..-nucleus dynamics at all energies. In exploring this new direction, it is important to have direct discussions among researchers with different viewpoints. Separate entries were prepared for the 49 papers presented. (WHK)
Date: October 1, 1983
Creator: Lee, T. S. H.; Geesaman, D. F. & Schiffer, J. P.
System: The UNT Digital Library
Further Studies on Equal-Order Interpolation for Navier-Stokes (open access)

Further Studies on Equal-Order Interpolation for Navier-Stokes

The simplest quadrilateral element available for the incompressible Navier-Stokes equations is the mixed interpolation 4-node element with bilinear velocity and (piecewise) constant pressure - denoted herein by 4/1. The next simplest is the 4/4 element, in which (continuous) bilinear approximation is also employed for pressure - i.e., the simplest case of equal-order interpolation. The 4/4 element had been more or less rejected early-on, following the pioneering work of Hood and Taylor who first discovered that equal-order interpolation generated spurious pressures. The 4/1 element, on the other hand, has been very popular, even though it sometimes generates one spurious pressure mode (vs many for the 4/4 element) which is usually filterable. But the 4/1 element generates a poor approximation to (Del P) when distorted elements are employed (via the bilinear isoparametric technique), which often leads to large errors in velocity; e.g. this element generated wrong answers for vortex shedding on the same mesh for which a higher order element (9/4) performed well. Although the 4/4 element generates ostensibly useless pressures, the pressure gradient and the velocity field might be much more accurate than those from the 4/1 element, especially when distorted meshes are employed. Based on these observations, we have successfully …
Date: October 1, 1983
Creator: Gresho, P. M.; Lee, R. L. & Sani, R. L.
System: The UNT Digital Library
Acoustic leak detection and ultrasonic crack detection (open access)

Acoustic leak detection and ultrasonic crack detection

A program is under way to assess the effectiveness of current and proposed techniques for acoustic leak detection (ALD) in reactor coolant systems. An ALD facility has been constructed and tests have begun on five laboratory-grown cracks (three fatigue and two thermal-fatigue and two field-induced IGSCC specimens. After ultrasonic testing revealed cracks in the Georgia Power Co. HATCH-1 BWR recirculation header, the utility installed an ALD system. Data from HATCH-1 have given an indication of the background noise level at a BWR recirculation header sweepolet weld. The HATCH leak detection system was tested to determine the sensitivity and dynamic range. Other background data have been acquired at the Watts Bar Nuclear Reactor in Tennessee. An ANL waveguide system, including transducer and electronics, was installed and tested on an accumulator safety injection pipe. The possibility of using ultrasonic wave scattering patterns to discriminate between IGSCCs and geometric reflectors has been explored. Thirteen reflectors (field IGSCCs, graphite wool IGSCCs, weld roots, and slits) were examined. Work with cast stainless steel (SS) included sound velocity and attenuation in isotropic and anisotropic cast SS. Reducing anisotropy does not help reduce attenuation in large-grained material. Large artificial flaws (e.g., a 1-cm-deep notch with a 4-cm …
Date: October 1, 1983
Creator: Kupperman, D.S.; Claytor, T.N. & Groenwald, R.
System: The UNT Digital Library
Comparisons of hydrodynamic beam models with kinetic treatments (open access)

Comparisons of hydrodynamic beam models with kinetic treatments

Hydrodynamic models have been derived by Mark and Yu and by others to describe energetic self-pinched beams, such as those used in ion-beam fusion. The closure of the Mark-Yu model is obtained with adiabatic assumptions mathematically analogous to those of Chew, Goldberger, and Low for MHD. The other models treated here use an ideal gas closure and a closure by Newcomb based on an expansion in V/sub th//V/sub z/. Features of these hydrodynamic beam models are compared with a kinetic treatment.
Date: October 6, 1983
Creator: Boyd, J. K.; Mark, J. W.; Sharp, W. M. & Yu, S. S.
System: The UNT Digital Library
Development of an operational multicomponent personnel neutron dosimeter/spectrometer DOSPEC (open access)

Development of an operational multicomponent personnel neutron dosimeter/spectrometer DOSPEC

A multicomponent dosimeter has been developed that uses an albedo detector to provide the measurement of low energy neutrons and as a screening element. It also contains track detector components, CR-39 and polycarbonate, which are only processed if the TLD indicates there has been an exposure to neutrons. Since the three components have significantly different energy responses, the dosimeter can act as a crude spectrometer. This report describes the dosimeter and briefly summarizes its use experience. 10 refs., 2 figs., 2 tabs.
Date: October 26, 1983
Creator: Griffith, R.V. & McMahon, T.A.
System: The UNT Digital Library
Cytometry of mammalian sperm (open access)

Cytometry of mammalian sperm

Male germ cells respond dramatically to a variety of insults and are important reproductive dosimeters. Semen analyses are very useful in studies on the effects of drugs, chemicals, and environmental hazards on testicular function, male fertility and heritable germinal mutations. The accessibility of male cells makes them well suited for analytical cytology. We might automate the process of determining sperm morphology but should not do so solely for increased speed. Rather, richer tangible benefits will derive from cytometric evaluation through increased sensitivity, reduced subjectivity, standardization between investigators and laboratories, enhanced archival systems, and the benefits of easily exchanged standardized data. Inroads on the standardization of assays for motility and functional integrity are being made. Flow cytometric analysis of total DNA content of individual sperm is an insensitive means to detect exposure to reproductive toxins because of the small size and low frequency of the DNA content errors. Flow cytometry can be applied to determine the proportions of X- and Y-sperm in semen samples.
Date: October 11, 1983
Creator: Gledhill, B.L.
System: The UNT Digital Library
Fabrication of a Set of Realistic Torso Phantoms for Calibration of Transuranic Nuclide Lung Counting Facilities (open access)

Fabrication of a Set of Realistic Torso Phantoms for Calibration of Transuranic Nuclide Lung Counting Facilities

A set of 16 tissue equivalent torso phantoms has been fabricated for use by major laboratories involved in counting transuranic nuclides in the lung. These phantoms, which have bone equivalent plastic rib cages, duplicate the performance of the DOE Realistic Phantom set. The new phantoms (and their successors) provide the user laboratories with a highly realistic calibration tool. Moreover, use of these phantoms will allow participating laboratories to intercompare calibration information, both on formal and informal bases. 3 refs., 2 figs.
Date: October 26, 1983
Creator: Griffith, R. V.; Anderson, A. L.; Sundbeck, C. W. & Alderson, S. W.
System: The UNT Digital Library
Control of gas input and background pressure in the end plug regions of the TMX-U thermal barrier experiment (open access)

Control of gas input and background pressure in the end plug regions of the TMX-U thermal barrier experiment

Rate equations for the plasma species in a thermal barrier end plug establish an upper bound on the neutral pressure (P) external to the plasma. For the Tandem Mirror Experiment-Upgrade (TMX-U), this bound is P less than or equal to 0.5 - 1.0 x 10/sup -6/ Torr. Initially TMX-U did not satisfy this criterion, and axial end plugging of plasma losses seemed limited by the excessive pressure. Subsequently, we modified the machine to improve the vacuum conditions, decreasing P to the desired range. At the same time axial end plugging of plasma losses increased to the duration of neutral beam injection and ECRH heating. Here we summarize our experimental measurements of gas input.
Date: October 26, 1983
Creator: Turner, W. C.; Nexsen, W. E.; Allen, S. L.; Hooper, E. B.; Hunt, A. L.; Lang, D. D. et al.
System: The UNT Digital Library
Linearity and resolution of photodiodes (open access)

Linearity and resolution of photodiodes

Measurements are reported of the resolution and linearity of Hamamatsu S1337 Photodiodes mounted on a NaI crystal and exposed to electron energy deposits of up to 80 GeV. The results indicate that these diodes can replace photomultipliers in high-light-yield detectors such as NaI and BGO, when operated in multi-element, compact assemblies in the presence of a magnetic field.
Date: October 1, 1983
Creator: van Driel, M.A. & Sens, J.C.
System: The UNT Digital Library
Memory intensive functional architecture for distributed computer control systems (open access)

Memory intensive functional architecture for distributed computer control systems

A memory-intensive functional architectue for distributed data-acquisition, monitoring, and control systems with large numbers of nodes has been conceptually developed and applied in several large-scale and some smaller systems. This discussion concentrates on: (1) the basic architecture; (2) recent expansions of the architecture which now become feasible in view of the rapidly developing component technologies in microprocessors and functional large-scale integration circuits; and (3) implementation of some key hardware and software structures and one system implementation which is a system for performing control and data acquisition of a neutron spectrometer at the Brookhaven High Flux Beam Reactor. The spectrometer is equipped with a large-area position-sensitive neutron detector.
Date: October 1, 1983
Creator: Dimmler, D.G.
System: The UNT Digital Library
Nuclear war: preliminary estimates of the climatic effects of a nuclear exchange (open access)

Nuclear war: preliminary estimates of the climatic effects of a nuclear exchange

The smoke rising from burning cities, industrial areas, and forests if such areas are attacked as part of a major nuclear exchange is projected to increase the hemispheric average atmospheric burden of highly absorbent carbonaceous material by 100 to 1000 times. As the smoke spreads from these fires, it would prevent sunlight from reaching the surface, leading to a sharp cooling of land areas over a several day period. Within a few weeks, the thick smoke would spread so as to largely cover the mid-latitudes of the Northern Hemisphere, cooling mid-continental smoke-covered areas by, perhaps, a few tens of degrees Celsius. Cooling of near coastal areas would be substantially less, since oceanic heat capacity would help to buffer temperature changes in such regions. The calculations on which these findings are based contain many assumptions, shortcomings and uncertainties that affect many aspects of the estimated response. It seems, nonetheless, quite possible that if a nuclear exchange involves attacks on a very large number of cities and industrial areas, thereby starting fires that generate as much smoke as is suggested by recent studies, substantial cooling could be expected that would last weeks to months over most continental regions of the Northern Hemisphere, …
Date: October 1, 1983
Creator: MacCracken, M.C.
System: The UNT Digital Library
Multichannel interval timer (open access)

Multichannel interval timer

A CAMAC based modular multichannel interval timer is described. The timer comprises twelve high resolution time digitizers with a common start enabling twelve independent stop inputs. Ten time ranges from 2.5 ..mu..s to 1.3 ..mu..s can be preset. Time can be read out in twelve 24-bit words either via CAMAC Crate Controller or an external FIFO register. LSB time calibration is 78.125 ps. An additional word reads out the operational status of twelve stop channels. The system consists of two modules. The analog module contains a reference clock and 13 analog time stretchers. The digital module contains counters, logic and interface circuits. The timer has an excellent differential linearity, thermal stability and crosstalk free performance.
Date: October 1, 1983
Creator: Turko, B.T.
System: The UNT Digital Library
Quantum chromodynamics in few-nucleon systems (open access)

Quantum chromodynamics in few-nucleon systems

One of the most important implications of quantum chromodynamics (QCD) is that nuclear systems and forces can be described at a fundamental level. The theory provides natural explanations for the basic features of hadronic physics: the meson and baryon spectra, quark statistics, the structure of the weak and electromagnetic currents of hadrons, the scale-invariance of hadronic interactions at short distances, and evidently, color (i.e., quark and gluon) confinement at large distances. Many different and diverse tests have confirmed the basic predictions of QCD; however, since tests of quark and gluon interactions must be done within the confines of hadrons there have been few truly quantitative checks. Nevertheless, it appears likely that QCD is the fundamental theory of hadronic and nuclear interactions in the same sense that QED gives a precise description of electrodynamic interctions. Topics discussed include exclusive processes in QCD, the deuteron in QCD, reduced nuclear amplitudes, and limitations of traditional nuclear physics. 32 references. (WHK)
Date: October 1, 1983
Creator: Brodsky, Stanley J.
System: The UNT Digital Library
Fracture behavior of zircaloy spent-fuel cladding (open access)

Fracture behavior of zircaloy spent-fuel cladding

The Zircaloy cladding of water reactor fuel rods is susceptible to local breach-type failure, commonly known as pellet-cladding interaction (PCI) failure, during operational and off-normal power transients after the fuel has achieved a sufficiently high burnup. An optimization of power ramp procedures or fuel rod fabrication to minimize the cladding failure would result in a significant decrease in radiation exposure of plant personnel due to background and airborne radioactivity as well as an extension of core life in terms of allowable off-gas radioactivity. As part of a program to provide a better understanding of the fuel rod faiure phenomenon and to facilitate the formulation of a better failure criterion, a mechanistic study of the deformation and fracture behavior of high-burnup spent-fuel cladding is in progress under simulated PCI conditions.
Date: October 1, 1983
Creator: Chung, H.M.; Yaggee, F.L. & Kassner, T.F.
System: The UNT Digital Library
Non-reactor neutron irradiation facility: the Argonne Intense Pulsed Neutron Source (open access)

Non-reactor neutron irradiation facility: the Argonne Intense Pulsed Neutron Source

A new generation of neutron sources is just coming into existence with great promise for the future. These sources are based on neutron production by spallation from the interaction of high energy protons with a heavy metal target. Currently the highest flux facility of this type is the Intense Pulsed Neutron Source at Argonne National Laboratory. This machine is also unique in its dedication to both slow-neutron scattering and fast-neutron damage studies.
Date: October 1, 1983
Creator: Birtcher, R. C. & Scott, T. L.
System: The UNT Digital Library
Fracture behavior of high-burnup spent-fuel cladding (open access)

Fracture behavior of high-burnup spent-fuel cladding

PCI-like, brittle-type failures, characterized by pseudocleavage-plus-fluting features in the fracture surface, branching cracks, and small diametral strain, were observed to occur at 292 to 325/sup 0/C in some batches of spent power-reactor fuel-cladding tubes under internal gas-pressurization and expanding-mandrel loading conditions in which the tests were not influenced by fission product simulants. Fractographic characteristics per se do not provide evidence for a PCI failure mechanism but should be deemed only as cooroborative in nature. Evaluation of TEM thin-foil specimens, obtained from regions adjacent to the brittle-type fracture sites, characteristically revealed extensive amounts of Zr/sub 3/O precipitates and a lack of slip dislocations. The precipitation of the Zr/sub 3/O phase appears to be enhanced by a high density of irradiation-induced defects. The brittle-type failure produced in the spent-fuel cladding tubes appears to be associated with segregation of oxygen to dislocation substructures and irradiation-induced defects, which leads to the formation of an ordered zirconium-oxygen phase of Zr/sub 3/O, an immobilization of dislocations, and minimal plastic deformation in the cladding material.
Date: October 1, 1983
Creator: Chung, H.M.; Yaggee, F.L. & Kassner, T.F.
System: The UNT Digital Library
Acoustic imaging of vapor bubbles through optically non-transparent media (open access)

Acoustic imaging of vapor bubbles through optically non-transparent media

A preliminary investigation of the feasibility of acoustic imaging of vapor bubbles through optically nontransparent media is described. Measurements are reported showing the echo signals produced by air filled glass spheres of various sizes positioned in an aqueous medium as well as signals produced by actual vapor bubbles within a water filled steel pipe. In addition, the influence of the metallic wall thickness and material on the amplitude of the echo signals is investigated. Finally several examples are given of the imaging of spherical bubbles within metallic pipes using a simulated array of acoustic transducers mounted circumferentially around the pipe. The measurement procedures and a description of the measuring system are also given.
Date: October 1, 1983
Creator: Kolbe, W.F.; Turko, B.T. & Leskovar, B.
System: The UNT Digital Library