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Acceleration of heavy ions in the AGS and CBA (open access)

Acceleration of heavy ions in the AGS and CBA

A plan has been developed to inject ion beams from the Brookhaven Tandem or a cyclotron added to the Tandem into the AGS. This beam could then be injected into a relativistic heavy ion collider. The availability of many CBA components adds to the attractiveness of this proposal.
Date: January 1, 1983
Creator: Barton, M. Q.
Object Type: Article
System: The UNT Digital Library
Accelerator breeder: a viable option for the production of nuclear fuels (open access)

Accelerator breeder: a viable option for the production of nuclear fuels

Despite the growing pains of the US nuclear power industry, our dependence on nuclear energy for the production of electricity and possibly process heat is likely to increase dramatically over the next few deacades. This statement dismisses fusion as being entirely too speculative to be practical within that time frame. Sometime, between the years 2000 and 2050, fissile material will be in short supply whether it is to fuel existing LWR's or to provide initial fuel inventory for FBR's. The accelerator breeder could produce the fuel shortfall predicted to occur during the first half of the 21st century. The accelerator breeder offers the only practical means today of producing, or breeding, large quantities of fissile fuel from fertile materials, albeit at high cost. Studies performed over the last few years at Chalk River Laboratory and at Brookhaven National Laboratory have demonstrated that the accelerator breeder is practical, technically feasible with state-of-the-art technology, and is economically competitive with any other proposed synthetic means of fissile fuel production. This paper gives the parameters of a nearly optimized accelerator-breeder system, then discusses the development needs, and the economics and institutional problems that this breeding concept faces.
Date: January 1, 1983
Creator: Grand, P.
Object Type: Article
System: The UNT Digital Library
Accelerator breeder with uranium, thorium target (open access)

Accelerator breeder with uranium, thorium target

An accelerator breeder, that uses a low-enriched fuel as the target material, can produce substantial amounts of fissile material and electric power. A study of H/sub 2/O- and D/sub 2/O-cooled, UO/sub 2/, U, (depleted U), or thorium indicates that U-metal fuel produces a good fissile production rate and electrical power of about 60% higher than UO/sub 2/ fuel. Thorium fuel has the same order of magnitude as UO/sub 2/ fuel for fissile-fuel production, but the generating electric power is substantially lower than in a UO/sub 2/ reactor. Enriched UO/sub 2/ fuel increases the generating electric power but not the fissile-material production rate. The Na-cooled breeder target has many advantages over the H/sub 2/O-cooled breeder target.
Date: January 1, 1983
Creator: Takahashi, H.; Powell, J. & Kouts, H.
Object Type: Article
System: The UNT Digital Library
Accounting for Time Dependent Source Variations in Surveillance Dosimetry Analysis (open access)

Accounting for Time Dependent Source Variations in Surveillance Dosimetry Analysis

One of the difficulties encountered in the calculation of dosimetry reaction rates is how to account for the time dependent behavior of the core source during the irradiation period. Indeed, even the obtaining of this source time dependence in adequate detail is not a trivial task. The straightforward approach of performing a DOT4 or similar transport calculation for each new relative source distribution, although correct, might be prohibitively expensive and time consuming when the irradiation period spans one or more complete fuel cycles, as it normally does. An alternative approach exists in the generation of a set of adjoint fluxes using DOT4 in the adjoint mode. Equations necessary for using adjoint approach on the Arkansas-1 reactor are presented.
Date: January 1, 1983
Creator: Maerker, R.E. & Williams, M.L.
Object Type: Article
System: The UNT Digital Library
Accretion Disks (open access)

Accretion Disks

Derivations are made for the mass and the mass-turnover time scale of an accretion disk as a function of the accretion rate, the observed disk radius, the non-viscous disk radius, and two parameters. These parameters depend on the effectiveness of viscosity and tidal angular momentum loss. Application is made to DQ Herculis.
Date: January 1, 1983
Creator: Sparks, Warren M. & Kutter, G.Siegfried
Object Type: Article
System: The UNT Digital Library
Accuracy of external personnel dosimetry systems in mixed neutron and gamma radiation fields (open access)

Accuracy of external personnel dosimetry systems in mixed neutron and gamma radiation fields

Estimates of biological effects associated with exposure to external radiation fields are generally based on the measured response of passive personnel dosimetry systems to the incident radiation. The increasing number of persons occupationally exposed to mixed neutron and gamma fields and recent questions concerning the relative biological hazards of different types of radiation have emphasized the need for accurate personnel radiation dose measurements. The performance characteristics of various neutron and gamma personnel dosimetry systems under actual mixed-field conditions have been determined. Analysis of the results indicates that significant inaccuracies can occur in neutron and gamma dose measurements in mixed radiation fields unless dosimeter performance and characteristics of the monitoring environment are considered in dosimeter evaluation. Neutron dose measurement accuracies could be improved by using dosimeters more suited to the anticipated radiation fields, calibrating dosimeters with sources appropriate for the energy spectra to be measured, applying correction factors to account for dosimeter performance in incident radiation fields, and standardizing the basis of reported dose equivalents. With regard to gamma monitoring, intercomparison results indicate that the selection of a basic dosimeter type which is relatively insensitive to neutrons is of great importance for accurate dose measurements in mixed fields.
Date: January 1, 1983
Creator: Swaja, R. E.
Object Type: Article
System: The UNT Digital Library
Acquisition systems for heat transfer measurement (open access)

Acquisition systems for heat transfer measurement

Practical heat transfer data acquisition systems are normally characterized by the need for high-resolution, low-drift, low-speed recording devices. Analog devices such as strip chart or circular recorders and FM analog magnetic tape have excellent resolution and work well when data will be presented in temperature versus time format only and need not be processed further. Digital systems are more complex and require an understanding of the following components: digitizing devices, interface bus types, processor requirements, and software design. This paper discusses all the above components of analog and digital data acquisition, as they are used in current practice. Additional information on thermocouple system analysis will aid the user in developing accurate heat transfer measuring systems.
Date: January 1, 1983
Creator: De Witt, R.J.
Object Type: Article
System: The UNT Digital Library
Actinide Behavior in a Freshwater Pond (open access)

Actinide Behavior in a Freshwater Pond

Long-term investigations of solution chemistry in an alkaline freshwater pond have revealed that actinide oxidation state behavior, particularly that of plutonium, is complex. The Pu(V,VI) fraction was predominant in solution, but it varied over the entire range reported from other natural aquatic environments, in this case, as a result of intrinsic biological and chemical cycles (redox and pH-dependent phenomena). A strong positive correlation between plutonium (Pu), but not uranium (U), and hydroxyl ion over the observation period, especially when both were known to be in higher oxidation states, was particularly notable. Coupled with other examples of divergent U and Pu behavior, this result suggests that Pu(V), or perhaps a mixture of Pu(V,VI), was the prevalent oxidation state in solution. Observations of trivalent actinide sorption behavior during an algal bloom, coupled with the association with a high-molecular weight (nominally 6000 to 10,000 mol wt) organic fraction in solution, indicate that solution-detritus cycling of organic carbon, in turn, may be the primary mechanism in amercium-curium (Am-Cm) cycling. Sorption by sedimentary materials appears to predominate over other factors controlling effective actinide solubility and may explain, at least partially, the absence of an expected strong positive correlation between carbonate and dissolved U. 49 references, …
Date: January 1, 1983
Creator: Trabalka, J. R.; Bogle, M. A. & Scott, T. G.
Object Type: Article
System: The UNT Digital Library
Active metasomatism in the Cerro Prieto geothermal system, Baja California, Mexico: a telescoped low pressure/temperature metamorphic facies series (open access)

Active metasomatism in the Cerro Prieto geothermal system, Baja California, Mexico: a telescoped low pressure/temperature metamorphic facies series

In the Cerro Prieto geothermal field, carbonate-cemented, quartzofeldspathic sediments of the Colorado River delta are being actively metasomatized into calc-silicate metamorphic rocks by reaction with alkali chloride brines between 200/sup 0/ and 370/sup 0/C, low fluid and lithostatic pressures, and low oxygen fugacities. Petrologic investigations of drill cores and cutting from over 50 wells in this field identified a prograde series of calc-silicate mineral zones which include as index minerals: wairakite, epidote, prehnite, and clinopyroxene. Associated divariant mineral assemblages are indicative of a very low pressure/temperature metamorphic facies series which encompasses the clay-carbonate, zeolite, greenschist, and amphibolite facies. This hydrothermal metamorphic facies series, which is becoming increasingly recognized in other active geothermal systems, is characterized by temperature-telescoped dehydration and decarbonation mineral equilibria. Its equivalent should now be sought in fossil hydrothermal systems.
Date: January 1, 1983
Creator: Schiffman, P.; Elders, W. A.; Williams, A. E.; McDowell, S. D. & Bird, D. K.
Object Type: Report
System: The UNT Digital Library
Active sites in char gasification. First quarterly progress report, September 1983-December 1983 (open access)

Active sites in char gasification. First quarterly progress report, September 1983-December 1983

This report reviews the background and motivation for this work, and discusses some initial scoping studies on chars similar to the model compounds to be used in later phases of the work. Some preliminary synthetic methodologies for model compounds are presented. 69 references.
Date: January 1, 1983
Creator: Suuberg, E. M.; Calo, J. M.; Wojtowicz, M. & Lilly, W.
Object Type: Report
System: The UNT Digital Library
ACTVE News, Volume 14, Number 1, January 1983 (open access)

ACTVE News, Volume 14, Number 1, January 1983

Newsletter issued by the Advisory Council for Technical-Vocational Education in Texas discussing news, events, and other relevant information related to technical and vocational education for adults in Texas.
Date: January 1983
Creator: Advisory Council for Technical-Vocational Education in Texas
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Adaptive Collocation Method For Simultaneous Heat and Mass Diffusion with Phase Change (open access)

Adaptive Collocation Method For Simultaneous Heat and Mass Diffusion with Phase Change

In post-accident heat removal applications the use of a lead slab is being considered for protecting a porous bed of steel shot in ex-vessel cavity from direct impingement of molten steel or fuel as released from reactor vessel following a hypothetical core disassembly accident in an LMFBR. The porous bed is provided to increase the coolability of the fuel debris by the sodium coolant. The present study is carried out to determine melting rates of a lead slab of various thicknesses by contact with sodium coolant and to evaluate the extent of penetration and the mixing rates of molten lead into liquid sodium by molecular diffusion alone. The study shows that these two calculations cannot be performed simultaneous without the use of adaptive coordinates which cause considerable stretching of the physical coordinates for mass diffusion. Because of the large difference in densities of these two liquid metals, the traditional constant density approximation for the calculation of mass diffusion cannot be used for studying their interdiffusion. The use of orthogonal collocation method along with adaptive coordinates produces extremely accurate results which are ascertained by comparing with the existing analytical solutions for concentration distribution for the case of constant density approximation and …
Date: January 1, 1983
Creator: Chawla, T. C.; Pedersen, D. R.; Leaf, G.; Minkowycz, W. J. & Shouman, A. R.
Object Type: Article
System: The UNT Digital Library
Advanced nuclear data for radiation-damage calculations (open access)

Advanced nuclear data for radiation-damage calculations

Accurate calculations of atomic displacement damage in materials exposed to neutrons require detailed spectra for primary recoil nuclei. Such data are not available from direct experimental measurements. Moreover, they cannot always be computed accurately starting from evaluated nuclear data libraries such as ENDF/B-V that were developed primarily for neutron transport applications, because these libraries lack detailed energy-and-angle distributions for outgoing charged particles. Fortunately, a new generation of nuclear model codes is now available that can be used to fill in the missing spectra. One example is the preequilibrium statistical-model code GNASH. For heating and damage applications, a supplementary code called RECOIL has been developed. RECOIL uses detailed reaction data from GNASH, together with angular distributions based on Kalbach-Mann systematics to compute the energy and angle distributions of recoil nuclei. The energy-angle distributions for recoil nuclei and outgoing particles are written out in the new ENDF/B File 6 format. The result is a complete set of nuclear data that can be used to calculate displacement-energy production, heat production, gas production, transmutation, and activation. Sample results for iron are given and compared to the results of conventional damage models such as those used in NJOY.
Date: January 1, 1983
Creator: MacFarlane, R.E. & Foster, D.G. Jr.
Object Type: Article
System: The UNT Digital Library
Advanced performance fusion engineering device based on low safety factor and current drive (FED-A) (open access)

Advanced performance fusion engineering device based on low safety factor and current drive (FED-A)

The FED-A study aims to quantify the potential improvement in cost-effectiveness of the Fusion Engineering Device (FED) by assuming low safety factor q at the plasma edge and noninductive current drive. The FED-A performance objectives (ignition, neutron wall load, and power-reactor-like operation) are set to be equal to or better than those of the FED Baseline. The results show that assuming magnetohydrodynamic (MHD) q/sub psi/ (edge) to be 1.8 permits reduction in device size and plasma current and leads to a 30% reduction in direct cost. A closely fitted, 1.5-cm-thick, continuous water-cooled shell made of the copper alloy AMAX-MZC (0.6 Cr, 0.1 Zr, 0.03 Mg) is proposed to provide a 0.5-s time constant, to help avoid disruption when q/sub psi/ passes near 2, and to mitigate disruption impact. The lower hybrid wave current drive in a cyclic density operation is proposed to achieve a quasi-steady-state operation permitting a design with low toroidal loop voltage and a 1000-s burn time.
Date: January 1, 1983
Creator: Peng, Y. K. M. & Rutherford, P. H.
Object Type: Article
System: The UNT Digital Library
Advanced research in solar-energy storage (open access)

Advanced research in solar-energy storage

The Solar Energy Storage Program at the Solar Energy Research Institute is reviewed. The program provides research, systems analyses, and economic assessments of thermal and thermochemical energy storage and transport. Current activities include experimental research into very high temperature (above 800/sup 0/C) thermal energy storage and assessment of novel thermochemical energy storage and transport systems. The applications for such high-temperature storage are thermochemical processes, solar thermal-electric power generation, cogeneration of heat and electricity, industrial process heat, and thermally regenerative electrochemical systems. The research results for five high-temperature thermal energy storage technologies and two thermochemical systems are described.
Date: January 1, 1983
Creator: Luft, W.
Object Type: Article
System: The UNT Digital Library
Advanced test accelerator (ATA), a 50 MeV, 10 kA induction linac (open access)

Advanced test accelerator (ATA), a 50 MeV, 10 kA induction linac

The ATA is an induction accelerator designed to produce 70 ns pulses of electrons at currents of 10 kA and energies in excess of 50 MeV. The accelerator is capable of operating at an average rate of 5 Hz or at 1 kHz for ten pulses. The parameters were chosen primarily to provide the experimental basis for advancing the understanding of electron beam propagation physics. The 85 m accelerator has been under construction for the past four years and has adopted mainly an improved version of the ETA technology to satisfy the required parameters. Initial operation of the facility and the energy conversion system from primary power to axial electric field will be described; recent advances in magnetic switching which have been incorporated in the innector will also be discussed.
Date: January 1, 1983
Creator: Reginato, L.
Object Type: Article
System: The UNT Digital Library
Advances in room-temperature solid-state gamma-ray spectrometry (open access)

Advances in room-temperature solid-state gamma-ray spectrometry

This article presents a review and analysis of different concepts of gamma-ray spectrometry using room-temperature solid-state detectors. The classical approach involving the use of a charge-sensitive preamplifier and attempting to collect all the ionization charge produced by the gamma ray is analyzed and discussed in terms of the charge transport parameters of the most promising compound semiconductor materials. It is concluded that compound semiconductor detector materials having a large disparity between the ..mu.. tau products for electrons and holes (such as HgI/sub 2/ and CdTe) will have rather poor energy resolution if the classical method of spectrometry requiring full charge collection is employed. 30 references.
Date: January 1, 1983
Creator: Iwanczyk, Jan S.
Object Type: Article
System: The UNT Digital Library
Advances in transmission x-ray optics (open access)

Advances in transmission x-ray optics

Recent developments in x-ray optics are reviewed. Specific advances in coded aperture imaging, zone plate lens fabrication, time and space resolved spectroscopy, and CCD x-ray detection are discussed.
Date: January 1, 1983
Creator: Ceglio, N.M.
Object Type: Article
System: The UNT Digital Library
Advantages and limitations of the SETS method. [PWR; BWR] (open access)

Advantages and limitations of the SETS method. [PWR; BWR]

The stability-enchancing two-step (SETS) method has been used successfully in the Transient Reactor Analysis Code (TRAC) for several years. The method consists of a basic semi-implicit step combined with a stabilizer step that, taken together, eliminate the material Courant stability limit associated with standard semi-implicit numerical methods. This approach toward stability requires significantly fewer computational operations than a fully implicit method, but currently maintains the first-order accuracy in space and time of its semi-implicit predecessors.
Date: January 1, 1983
Creator: Mahaffy, J.H.
Object Type: Article
System: The UNT Digital Library
Advantages of spatial and temporal segmentation for detectors at high-luminosity c-w colliders (open access)

Advantages of spatial and temporal segmentation for detectors at high-luminosity c-w colliders

A major detector problem at high energy colliders independent of the luminosity is the ability to resolve particles inside jets. Only in very spacial cases, e.g., UAl W+- production with P/sub T/ = M/sub W//2 will enough of the signal be clear of jets, so that events with tracks in jets can be summarily rejected. Eventually, detectors will have to cope with tracks in jets. The high track density requires good track-pair resolution and efficiency, which implies wire chambers with drift distances of 2 mm or less, independent of the luminosity. The small drift distances required by the jet physics are very helpful at high luminosities since the maximum drift time of 40 nsec limits the pile-up to an average of 2 events at a luminosity of 10/sup 33/ cm/sup -2/sec/sup -1/. The segmentation of calorimeters is also set by jet physics and the desire to resolve and measure collimated jets. Characteristics of some segmented detectors are briefly discussed. (WHK)
Date: January 1, 1983
Creator: Tannenbaum, Michael J.
Object Type: Article
System: The UNT Digital Library
AEM/STEM analysis of vapor-deposited multilayered laser targets (open access)

AEM/STEM analysis of vapor-deposited multilayered laser targets

S(TEM) examinations were made to augment other types of measurements of absolute density. The structure of the 5 ..mu..m thick layers of aluminum and gold on aluminum laminate gold substrate was examined to establish film integrity, to characterize the microstructure, as well as to estimate the surface roughness of this multilayer material.
Date: January 1, 1983
Creator: Johnson, K. A.; Staudhammer, K. P.; Reeves, G. A. & Vesser, L. R.
Object Type: Article
System: The UNT Digital Library
The Age, Volume 4, Number 2, January 1, 1983 (open access)

The Age, Volume 4, Number 2, January 1, 1983

Monthly publication containing information related to Chambers County, Texas, including current events of the Chambers County Historical Commission, the Wallisville Heritage Park, and the Chambers County historical and genealogical societies; reprinted newspaper articles about county events and citizens; and historical news and records.
Date: January 1, 1983
Creator: Wallisville Heritage Park (Organization)
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Aging of electronics with application to nuclear power plant instrumentation. [PWR; BWR] (open access)

Aging of electronics with application to nuclear power plant instrumentation. [PWR; BWR]

A survey to identify areas of needed research to understand aging mechanisms for electronics in nuclear power plant instrumentation has been completed. The emphasis was on electronic components such as semiconductors, capacitors, and resistors used in safety-related instrumentation in the reactor containment area. The environmental and operational stress factors which may produce degradation during long-term operation were identified. Some attention was also given to humidity effects as related to seals and encapsulants, and failures in printed circuit boards and bonds and solder joints. Results suggest that neutron as well as gamma irradiations should be considered in simulating the aging environment for electronic components. Radiation dose-rate effects in semiconductor devices and organic capacitors need to be further investigated, as well as radiation-voltage bias synergistic effects in semiconductor devices and leakage and permeation of moisture through seals in electronics packages.
Date: January 1, 1983
Creator: Johnson, R. T., Jr.; Thome, F. V. & Craft, C. M.
Object Type: Article
System: The UNT Digital Library
AGS new fast extraction system and the single bunch extraction test (open access)

AGS new fast extraction system and the single bunch extraction test

For the neutrino physics program and for the CBA injection, a new fast extraction system has been implemented to improve the extraction efficiency and the quality of the extracted beam. Central to the new system is a new fast kicker, placed at the H5 straight section, capable of rising between bunches, t/sub r/ < 170 nsec, and staying constant for 2.6 ..mu..sec with flat top ripple less than +-1.5%. So far, the system has been operated for longer than 3000 hours and routinely extracts 10/sup 13/ ppp at 99% efficiency. Experiment 745 on QCD test requires a single AGS bunch of 40 nsec. For this purpose another fast kicker was placed at the E5 straight section and powered by a new pulser to produce a half sinusoidal pulse with both a rise and fall time of 200 nsec. A single AGS bunch was extracted through the slow beam channel at 22 GeV/c leaving the remaining 11 bunches undisturbed which continued to be accelerated to 29.4 GeV/c and extracted by the H5 kicker through the fast beam channel. Because the ring circumference ratio of CBA to the AGS is 4-3/4, some of the injected beam from the AGS has to contain …
Date: January 1, 1983
Creator: Weng, W. T.
Object Type: Article
System: The UNT Digital Library