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Total hadron cross section, new particles, and muon electron events in e/sup +/e/sup -/ annihilation at SPEAR
The review of total hadron electroproduction cross sections, the new states, and the muon--electron events includes large amount of information on hadron structure, nine states with width ranging from 10's of keV to many MeV, the principal decay modes and quantum numbers of some of the states, and limits on charm particle production. 13 references. (JFP)
Date:
January 1, 1976
Creator:
Richter, B.
System:
The UNT Digital Library
Design and operation of an inert gas facility for thermoelectric generator storage
While the flight hardware is protected by design from the harsh environments of space, its in-air storage often requires special protection from contaminants such as dust, moisture and other gases. One of these components, the radioisotope thermoelectric generator (RTG) which powers the missions, was deemed particularly vulnerable to pre-launch aging because the generators remain operational at core temperatures in excess of 1000 degrees centigrade throughout the storage period. Any oxygen permitted to enter the devices will react with thermally hot components, preferentially with molybdenum in the insulating foils, and with graphites to form CO/CO{sub 2} gases which are corrosive to the thermopile. It was important therefore to minimize the amount of oxygen which could enter, by either limiting the effective in-leakage areas on the generators themselves, or by reducing the relative amount of oxygen within the environment around the generators, or both. With the generators already assembled and procedures in place to assure minimal in-leakage in handling, the approach of choice was to provide a storage environment which contains significantly less oxygen than normal air. 2 refs.
Date:
January 1, 1990
Creator:
Goebel, C. J.
System:
The UNT Digital Library
Microwave separation of organic chemicals from mixed hazardous waste
The feasibility of utilizing the differential heating characteristics of microwave energy (MW) to aid in the chemical extraction and separation process of hazardous organic compounds from mixed hazardous waste, was studied at the INEL. The long-term objective of this work was to identify a practical method of separating or enhancing the separation process of organic hazardous waste components from mixed waste using microwave (MW) frequency radiation. Methods using MW energy for calcination, solidification, and drying of radioactive waste from nuclear facilities is becoming more attractive. In order to study the effectiveness of MW heating, samples of several organic chemicals simulating those which may be found at the Radioactive Waste Management Complex at the INEL were exposed to MW energy. Vapor collection and analysis was performed as a function of time, signal frequency, and MW power throughout the process. Signal frequencies ranging from 900 MHz t 8000 MHz were used. Although the signal frequency bandwidth of the selectivity was quite broad, for the material tested an indication of the frequency dependence in the selectivity of MW heating was given. Greater efficiency in terms of energy used and time required was observed. The relatively large electromagnetic field intensities generated at the resonant …
Date:
January 1, 1992
Creator:
Anderson, A. A. & Albano, R. K.
System:
The UNT Digital Library
Pseudorapidity distributions and correlations in central sup 16 O interactions at 200 A GeV
Whether or not adequate energy densities for a transition to the Quark-Gluon Plasma (QGP) phase are possible in {sup 16}O and {sup 32}S induced reactions is still an open question. Before unambiguous signals can be identified it is necessary to understand the background upon which the expected QGP signatures can be sought. An important aim of early experiments in this new energy density regime is thus to understand the process of hadronization in a nuclear environment. In any discussion of high energy nucleus-nucleus collisions formation time is an important feature. If, for example, the final state particles are produced instantaneously in a bound hadron-nucleon collision, all these particles will have a chance to reinteract inside the nuclear medium. If, on the other hand, the formation time is long, i.e., longer than the nuclear diameter, the energy flux will stay together as a unit throughout its passage through the target nucleus. While these extreme cases are clearly unrealistic, one expects interaction parameters such as the multiplicity and pseudorapidity distributions to be sensitive functions of the formation time. Here we present results on charged hadron production in an experiment using tracking detectors with the highest possible spatial resolution: emulsion chambers. A sample …
Date:
January 1, 1988
Creator:
Wilkes, R. J.
System:
The UNT Digital Library
Model for the control of dissolved manganese in the interstitial waters of Chesapeake Bay
None
Date:
January 1, 1975
Creator:
Holdren, G. R., Jr.; Bricker, O. P., III & Matisoff, G.
System:
The UNT Digital Library
Alignment and focusing device for a multibeam laser system
Large inertial confinement fusion laser systems have many beams focusing on a small target. The Antares system is a 24-beam CO/sub 2/ pulse laser. To produce uniform illumination, the 24 beams must be individually focused on (or near) the target's surface in a symmetric pattern. To assess the quality of a given beam, we will locate a Smartt (point diffraction) interferometer at the desired focal point and illuminate it with an alignment laser. The resulting fringe pattern shows defocus, lateral misalignment, and beam aberrations; all of which can be minimized by tilting and translating the focusing mirror and the preceding flat mirror. The device described in this paper will remotely translate the Smartt interferometer to any position in the target space and point it in any direction using a two-axis gimbal. The fringes produced by the interferometer are relayed out of the target vacuum shell to a vidicon by a train or prisms. We are designing four separate snap-in heads to mount on the gimbal; two of which are Smartt interferometers (for 10.6 ..mu..m and 633 nm) and two for pinholes, should we wish to put an alignment beam backwards through the system.
Date:
January 1, 1980
Creator:
Sweatt, W.C.
System:
The UNT Digital Library
In-Vitro and in-Vivo Characterization of Ruthenium-Bleomycin Compared to Cobalt- and Copper-Bleomycin
Bleomycin (BLM) has undergone extensive investigation both as a cancer chemotherapeutic agent, and as a carrier for radionuclides for tumor imaging. The available methods or the radionuclides used, however, have had limited effectiveness. Although labeling of BLM with /sup 103/Ru has been reported earlier, we carried out a study to develop a more reproducible method of labeling particularly for use with Brookhaven Linac Isotope Producer produced /sup 97/Ru. Ruthenium-97 has favorable physical properties that make it ideal for imaging applications: decay by electron capture; ..gamma.. 216 keV, 85%; t/sub 1/2/ 2.9 d. A novel method based on the reduction of Ru/sup 3 +/ to Ru/sup 2 +/ using stannous chloride was investigated for labeling BLM with /sup 97/Ru and/or /sup 103/Ru. In-vitro and in vivo comparisons of the product(s) with /sup 57/Co and /sup 67/Cu-labeled BLM were also carried out. 4 refs., 3 tabs.
Date:
January 1, 1986
Creator:
Shao, H. S.; Meinken, G. E.; Srivastava, S. C.; Slosman, D.; Sacker, D. F.; Som, P. et al.
System:
The UNT Digital Library
Radiation dosimetry through spectral definition
We have developed a fieldable instrumentation system for determining from measured flux spectra, both the neutron and gamma ray dose rate distributions associated with radioactive sources. This system includes the sensors, the computer-based data acquisition and analysis hardware, and the requisite software for unfolding the sensor response functions to obtain the flux spectra, and for folding the resultant flux spectra with appropriate flux spectrum-to-dose conversion factors. We use bismuth germanate scintillators that have experimentally measured and analytically interpolated response functions to determine the gamma ray flux spectra, and a suite of neutron sensors, based on proton recoil and /sup 3/He capture, to determine the neutron flux spectra. In addition, gamma ray peak identification is done using HPGe sensors. We describe the equipment and procedures and present some recent results. 10 refs., 15 figs.
Date:
January 1, 1985
Creator:
Dowdy, E. J.; Moss, C. E.; Robba, A. A.; Evans, A. E.; Lucas, M. C.; Shunk, E. R. et al.
System:
The UNT Digital Library
A theoretical prediction of critical heat flux in subcooled pool boiling during power transients
Understanding and predicting critical heat flux (CHF) behavior during steady-state and transient conditions are of fundamenatal interest in the design, operation, safety of boiling and two-phase flow devices. This paper discusses the results of a comprehensive theoretical study made specifically to model transient CHF behavior in subcooled pool boiling. This study is based upon a simplified steady-state CHF model in terms of the vapor mass growth period. The results obtained from this theory indicate favorable agreement with the experimental data from cylindrical heaters with small radii. The statistical nature of the vapor mass behavior in transient boiling also is considered and upper and lower limits for the current theory are established. Various factors that affect the discrepancy between the data and the theory are discussed.
Date:
January 1, 1988
Creator:
Pasamehmetoglu, K. O.; Nelson, R. A. & Gunnerson, F. S.
System:
The UNT Digital Library
Neutron scattering from solutions: the hydration of lanthanide and actinide ions
The neutron scattering difference method is described and applied to investigations of the aqua rare-earth ions, Nd/sup 3 +/ and Dy/sup 3 +/. Metal-water distances and hydration numbers have been unambiguously determined for these ions' inner coordination spheres. The values of the hydration number, n, of 8.5 +- 0.2 for Nd/sup 3 +/ and 7.4 +- 0.5 for Dy/sup 3 +/, directly support the claim of Spedding et al. that n decreases by one unit across the lanthanide series. The possible application of this method to actinide ions in solution is also discussed. 7 refs., 4 figs.
Date:
January 1, 1985
Creator:
Hahn, R.L.; Narten, A.H. & Annis, B.K.
System:
The UNT Digital Library
Colorado State University Solar Heated and Cooled House
None
Date:
January 1, 1974
Creator:
Lof, G.O.G.
System:
The UNT Digital Library
Clonal theory of radiation carcinogenesis
In some cases, usually involving high-LET radiations, the dose response at low doses follows a power function of dose with exponent less than one over a wide dose range. This type of response is of great interest since (a) it implies greater effect per unit dose at progressively smaller doses, and (b) it is not predicted by most models and theories of radiobiology. A theoretical framework is presented for responses having the above characteristics over a dose range extending over a factor of 1000. The model postulates precursor cells which occur in clones. Different numbers of precursor cells per clone are assumed. Suitable transformation of a single cell in a clone completes initiation of that clone and raises the probability of tumor formation. At low doses, clones with large numbers of cells at risk have relatively high probability of response. However, depletion of the number of untransformed large clones with increasing dose leaves primarily untransformed smaller clones with smaller probability of response per unit dose. The analytical results demonstrate that power functions with exponent less than one can result even for doses so small that the mean number of charged particle traversals per cell is much less than one. The …
Date:
January 1, 1982
Creator:
Baum, J.W.
System:
The UNT Digital Library
A semi-analytical method for heat sweep calculations in fractured reservoirs
An analytical approximation is developed for purely conductive heat transfer from impermeable blocks of rock to fluids sweeping past the rocks in fractures. The method was incorporated into a multi-phase fluid and heat flow simulator. Comparison with exact analytical solutions and with simulations using a multiple interacting continua approach shows very good accuracy, with no increase in computing time compared to porous medium simulations. 14 refs., 3 figs., 5 tabs.
Date:
January 1, 1988
Creator:
Pruess, K. & Wu, Y.S.
System:
The UNT Digital Library
Radiation-induced segregation in HT-9 martensitic steel
Miniature notched-bar specimens of normalized and tempered HT-9 were neutron irradiated to approx.13 dpa and broken at liquid nitrogen temperatures in a UHV chamber. Fracture surfaces were analyzed using scanning Auger electron spectroscopy. Following irradiation at 410/sup 0/C, the fracture surface contained a small number of large relatively smooth facets, which are thought to be prior austenite grain boundaries. Strong segregation of Ni, Cr, Si, and P was detected at these surfaces, the remainder of the fracture surface showing no evidence of segregation. At irradiation temperatures of 520/sup 0/ and 565/sup 0/C, there was relatively little segregation and none was found in thermal controls.
Date:
January 1, 1986
Creator:
Clausing, R.E.; Heatherly, L.; Faulkner, R.G.; Rowcliffe, A.F. & Farrell, K.
System:
The UNT Digital Library
Status of the translawrencium elements (Z > 103)
As a result of conflicting claims to the discovery of the trans-lawrencium elements (Z > 103), IUPAC's Inorganic Chemistry Nomenclature Commission, (II.2), has been incapable of coming to a decision on rightful discoverer for these elements. In addition, the Atomic Weights Commission, (II.1), has from time to time been interested in the status of the search for the superheavy elements, i.e., those elements which might be found in the vicinity of the 'island of stability'. Theoretical studies have indicated that the next major shell closures beyond Z = 82 and N = 126 would occur at Z = 114 and N = 184. In recent years, many scientists have devoted their time and effort in an attempt to detect these superheavy elements. This paper will review the literature on both of these developments and provide an up-to-date status report for the use of the Commission. However, this paper will not address the pros and cons of the controversial systematic naming scheme proposed by the Nomenclature Commission, (II.2) and approved by IUPAC. 56 refs.
Date:
January 1, 1985
Creator:
Holden, Norman E.
System:
The UNT Digital Library
Detection of plasma equilibrium shifts with fiber optic sensing of image currents
The radial equilibrium position of Reverse Field Pinch experiments is determined by the j x B force on the plasma. The current density is that of the toroidal plasma current and the B field is the vertical magnetic field which is present in the plasma. This magnetic field is the result of several components. The main field, generated by the toroidal current windings, is corrected by adjustable trim windings to achieve a desired equilibrium position. There is an additional component to the field due to induced image currents in the close fitting conducting shell which encircles the plasma. These currents vary in time due to the finite L/R time of the conducting shell. It is the object of this paper to investigate the possibility of measuring these shell currents accurately using fiber optics so as to provide an analog signal to the equilibrium feedback circuit. 7 refs., 7 figs.
Date:
January 1, 1988
Creator:
Forman, P.R.; Jahoda, F.C. & Miller, G.
System:
The UNT Digital Library
Estimate of the longitudinal self electric field of an ion beam
The self electric field on the axis of an ion beam of radius a in a conducting cylinder of radius b is given. The formula assumes that the radius of the conducting cylinder is much smaller than the length of the ion beam (b much less than L) and that E/sub z/ is calculated away from the edge of the beam (vertical bar z vertical bar less than vertical bar L/2 vertical bar). For the HIDE parameters, i.e., loosely speaking a 50 TW, 100 JK, multi-GeV heavy ion beam, the assumption b much less than L is no longer valid and hence this equation cannot be used. Since for an unneutralized heavy ion beam it is necessary to apply ramp voltages to compensate for the longitudinal self fields it is desirable to know exactly what these fields are. Here, exact expressions for E/sub z/ on the axis of the ion beam are obtained and are compared under different circumstances with the approximate results given by the equation.
Date:
January 1, 1977
Creator:
Irani, A.A.
System:
The UNT Digital Library
Critical review of a quantitative study of a specialty in high energy particle physics
A review is made of the authors' series of quantitative, historical, and social studies of the weak interactions of elementary particles. A short intellectual history, the quantitative methodology, and a summary of the papers analyzing specific episodes in this field are presented. The social organization of the field is described, and an overall policy for resource management is discussed. 6 figures, 3 tables.
Date:
January 1, 1980
Creator:
White, D H & Sullivan, D
System:
The UNT Digital Library
Fractional processes and nuclear disassembly in very-heavy-ion collisions in the Fermi energy regime
Exclusive measurements of charged products and neutrons were performed for the reactions {sup 197}Au + (29 MeV/u) {sup 208}Pb and {sup 209}Bi + (28.2 MeV/u) {sup 136}Xe. The multiplicities of neutrons and charged particles are found to indicate collision impact parameters with different sensitivities. Characteristic correlations observed between massive products and light particles suggest the dominance of the damped-reaction mechanism in the Fermi energy domain. For central collisions, massive fragments are no longer observed, and a considerable fraction of the mass of the system is found disassembled into light particles and clusters. 75 refs., 19 figs.
Date:
January 1, 1991
Creator:
Schroeder, W.U.
System:
The UNT Digital Library
Seismic response analysis for structures with non-orthogonal modes
For seismic analysis of structures in nuclear industry, the spectrum method of modal combination acceptable to US Nuclear Regulatory Commission is applicable only to systems with orthogonal natural modes. When a structure with frequency dependent boundary conditions is set in motion, its natural modes of vibration are generally non-orthogonal. Based on such a structure, the spectrum method of modal composition is generalized to include systems with non-orthogonal modes. The generalized expression for the participation factor of each model is reducible to that prescribed by NRC, when the natural modes of the system are orthogonal. To illustrate the generalized method, the model responses of a simple structure are analyzed in detail.
Date:
January 1, 1980
Creator:
Yau, W. F.
System:
The UNT Digital Library
Deposition and removal of radioactive isotopes from LMFBR components
The development of an analytical model to describe the production, transport and eventual removal of radioactive materials in the primary sodium of LMFBR's is a continuing Sodium Technology activity sponsored by the Department of Energy. This paper describes studies directed toward obtaining an understanding of the deposition from sodium of fuel cladding activated corrosion products onto stainless steel alloys and the effect of their diffusion into the base metal on the process required to decontaminate it. The objective of the decontamination operation is to reduce the activity to a level allowing hands on maintenance without causing unacceptable damage to the component.
Date:
January 1, 1980
Creator:
Hill, E. F.; Lutton, J. M. & Maffei, H. P.
System:
The UNT Digital Library
Organic iodine removal from simulated dissolver off-gas streams using silver-exchanged mordenite
The removal of methyl iodide by absorption onto silver mordenite was studied using a simulated off-gas from the fuel dissolution step of a nuclear fuel reprocessing plant. The methyl iodide absorption of silver mordenite was examined for the effects of NO/sub x/, humidity, iodine concentration, filter temperature, and filter pretreatment. The highest iodine loading achieved in these tests has been 34 mg CH/sub 3/I per g of substrate, approximately five times less than the elemental iodine loadings. Results indicate that a filter operating at a temperature of 150/sup 0/C obtained higher iodine loadings than a similar filter operating at 100/sup 0/C. Pretreatment of the sorbent bed with hydrogen, rather than dry air, at a temperature of 200/sup 0/C also improved the loading. Variations in the methyl iodide concentration had minimal effects on the overall loading. Filters exposed to moist air streams attained higher loadings than those in contact with dry air. A study of the regeneration characteristics of silver mordenite indicates limited adsorbent capacity after complete removal of the iodine with 4% hydrogen in the regeneration gas stream at 500/sup 0/C. 9 figures.
Date:
January 1, 1980
Creator:
Jubin, R. T.
System:
The UNT Digital Library
Vibration considerations in the design of the Advanced Photon Source at Argonne National Laboratory
The Advanced Photon Source (APS), a new synchrotron radiation facility being built at Argonne National Laboratory, will provide the world's most brilliant X-ray beams for research in a wide range of technical fields. Successful operation of the APS requires an extremely stable positron closed orbit. Vibration of the storage ring quadrupole magnets, even in the submicron range, can lead to distortion of the positron closed orbit and to potentially unacceptable beam emittance growth, which results in degraded performance. This paper presents an overview of the technical approach used to minimize vibration response, beginning at the conceptual stage, through design and construction, and on to successful operation. Acceptance criteria relating to maximum allowable quadrupole magnet vibration are discussed. Soil properties are used to determine resonant frequencies of foundations and to predict attenuation characteristics. Two sources are considered to have the potential to excite the foundation: far-field sources, which are produced external to the facility, and near-field sources, which are produced within the facility. Measurements of ambient ground motion, monitored to determine far- field excitation, are presented. Ambient vibration was measured at several operating facilities within Argonne to gain insight on typical near-field excitation sources. Discussion covers the dynamic response characteristics of …
Date:
January 1, 1991
Creator:
Jendrzejczyk, J.A. & Wambsganss, M.W.
System:
The UNT Digital Library
Aging Aircraft NDI Development and Demonstration Center (AANC): An overview
A major center with emphasis on validation of nondestructive inspection techniques for aging aircraft, the Aging Aircraft NDI Development and Demonstration Center (AANC), has been funded by the FAA at Sandia National Laboratories. The Center has been assigned specific tasks in developing techniques for the nondestructive inspection of static engine parts, assessing inspection reliability (POD experiments), developing test beds for nondestructive inspection validation, maintaining a FAA library of characterized aircraft structural test specimens, and leasing a hangar to house a high flight cycle transport aircraft for use as a full scale test bed. 3 refs.
Date:
January 1, 1991
Creator:
Walter, P. L.
System:
The UNT Digital Library