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Quantification of Libby Reservoir Levels Needed to Maintain or Enhance Reservoir Fisheries, 1983-1987 Methods and Data Summary.

Description: Libby Reservoir was created under an International Columbia River Treaty between the United States and Canada for cooperative water development of the Columbia River Basin. The authorized purpose of the dam is to provide power, flood control, and navigation and other benefits. Research began in May 1983 to determine how operations of Libby dam impact the reservoir fishery and to suggest ways to lessen these impacts. This study is unique in that it was designed to accomplish its goal through detailed information gathering on every trophic level in the reservoir system and integration of this information into a quantitative computer model. The specific study objectives are to: quantify available reservoir habitat, determine abundance, growth and distribution of fish within the reservoir and potential recruitment of salmonids from Libby Reservoir tributaries within the United States, determine abundance and availability of food organisms for fish in the reservoir, quantify fish use of available food items, develop relationships between reservoir drawdown and reservoir habitat for fish and fish food organisms, and estimate impacts of reservoir operation on the reservoir fishery. 115 refs., 22 figs., 51 tabs.
Date: December 1, 1989
Creator: Chisholm, Ian
Partner: UNT Libraries Government Documents Department

Engineering Physics and Mathematics Division progress report for period ending August 31, 1989

Description: This paper contains abstracts on research performed at the Engineering Physics and Mathematics Division of Oak Ridge National Laboratory. The areas covered are: mathematical science; nuclear-data measurement and evaluation; intelligent systems; nuclear analysis and shielding; and Engineering Physics Information Center. (LSP)
Date: December 1, 1989
Partner: UNT Libraries Government Documents Department

Reaction of Tris(cyclopentadienyl)uranium compounds with amines, azides, and related ligands

Description: The trivalent uranium compound, (MeC{sub 5}H{sub 4}){sub 3}U(thf), serves as a one- or two-electron reducing agent towards azides, RN{sub 3}. These reactions produce either the uranium(IV) azide, (MeC{sub 5}H{sub 4}){sub 3}UN{sub 3}, or uranium(V) imides, (MeC{sub 5}H{sub 4}){sub 3}UNR. The role of steric and electronic effects upon this reaction has been investigated using several series of azides. For Me{sub 3}XN{sub 3}, the imides are produced when X = C or Si, both products are formed when X = Ge, and the azide is produced when X = Sn. For Ph{sub 3}XN{sub 3}, the azide is produced when X = C or Sn. For Ph{sub 3-x}CH{sub 3}N{sub 3}, the imide is produced when x = 2 and both compounds are produced when x = 1. For substituted phenylazides, RC{sub 6}H{sub 4}N{sub 3}, only the imides are produced. The magnetic properties of uranium diimides, ((MeC{sub 5}H{sub 4}){sub 3}U){sub 2}({mu}-NRN), were investigated. Several uranium(III) amines, (MeC{sub 5}H{sub 4}){sub 3}U(NH{sub 2}R), were produced from (MeC{sub 5}H{sub 4}){sub 3}U(thf) and RNH{sub 2}, and NH{sub 3} was found to be a better ligand towards (MeC{sub 5}H{sub 4}){sub 3}U than is PMe{sub 3}.
Date: December 1, 1989
Creator: Rosen, Robert Keith
Partner: UNT Libraries Government Documents Department

Intrabeam scattering in the Tevatron collider upgrade

Description: This report explores the effects of intrabeam scattering on the integrated luminosity for some conditions under consideration for the early stages of the Tevatron collider upgrade. This report concludes that intrabeam scattering effects, although they are hoped to become clearly visible, are not expected to wash out gains made by lowering {beta}* and emittances. It is not the intent of this report to provide a physics tutorial on intrabeam scattering. However, a bibliography is provided at the end of this report which may be of use in that regard. 14 figs.
Date: December 4, 1989
Creator: Finley, D.
Partner: UNT Libraries Government Documents Department

Hadron production in relativistic heavy ion interactions and the search for the quark-gluon plasma

Description: The course starts with an introduction, from the experimentalist's point of view, of the challenge of measuring Relativistic Heavy Ion interactions. A review of some theoretical predictions for the expected signatures of the quark gluon plasma will be made, with a purpose to understand how they relate to quantities which may be experimentally measured. A short exposition of experimental techniques and details is given including charged particles in matter, momentum resolution, kinematics and Lorentz Transformations, calorimetry. Principles of particle identification including magnetic spectrometers, time of flight measurement. Illustrations using the E802 spectrometer and other measured results. Resolution smearing of spectra, and binning effects. Parent to daughter effects in decay, with {pi}{sup 0} {yields} {gamma} {gamma} as an example. The experimental situation from the known data in p -- p collisions and proton-nucleus reactions is reviewed and used as a basis for further discussions. The Cronin Effect'' and the Seagull Effect'' being two arcana worth noting. Then, selected experiments from the BNL and CERN heavy ion programs are discussed in detail. 118 refs., 45 figs.
Date: December 1, 1989
Creator: Tannenbaum, M. J.
Partner: UNT Libraries Government Documents Department

Physical sputtering of metallic systems by charged-particle impact

Description: The present paper provides a brief overview of our current understanding of physical sputtering by charged-particle impact, with the emphasis on sputtering of metals and alloys under bombardment with particles that produce knock-on collisions. Fundamental aspects of ion-solid interactions, and recent developments in the study of sputtering of elemental targets and preferential sputtering in multicomponent materials are reviewed. We concentrate only on a few specific topics of sputter emission, including the various properties of the sputtered flux and depth of origin, and on connections between sputtering and other radiation-induced and -enhanced phenomena that modify the near-surface composition of the target. The synergistic effects of these diverse processes in changing the composition of the integrated sputtered-atom flux is described in simple physical terms, using selected examples of recent important progress. 325 refs., 27 figs.
Date: December 1, 1989
Creator: Lam, N. Q.
Partner: UNT Libraries Government Documents Department

Activation of methane by transition metal-substituted aluminophosphate molecular sieves

Description: Recent experiments in our laboratory have demonstrated that aluminophosphate molecular sieves substituted with cobalt and cobalt/silicon combinations and having the AlPO{sub 4}-34 or AlPO{sub 4}-5 structure activate methane starting at {approximately}350{degree}C. Between 400 and 500{degree}C the rate of methane conversion increases steadily with typical conversion efficiencies at 500{degree}C ranging from 15 to 60%. The cobalt and silicon substituted AlPO{sub 4}-34 structure (CoAPSO-34) produces ethylene, ethane, propylene, and propane in varying proportions, depending on reactions conditions. The cobalt-substituted AlPO{sub 4}-5 (CoAPSO-5) produces propylene in very high yield with ethane, ethylene, and propane also seen. Analogous aluminophosphate molecular sieves substituted with magnesium or silicon, but containing no transition metal (e.g., SAPO-34, MAPO-5), do not activate methane under the conditions described above. The activation mechanism is based on reduction of the cobalt(III) form of the molecular sieve to the cobalt(II) form with accompanying oxidative dehydrogenation of the methane. Reoxidation of the cobalt(II) for to the cobalt(III) form can be done either chemically (e.g., using O{sub 2}) or electrochemically. 7 refs., 2 figs., 1 tab.
Date: December 1, 1989
Creator: Maroni, V A; Willms, K A; Nguyen, Hiephoa & Iton, L E
Partner: UNT Libraries Government Documents Department

A new model for solvent extraction in columns

Description: A new model was developed for analyzing solvent extraction processes carried out in columns. Each column is treated as a series of well-defined equilibrium stages where the backmixing (other-phase carryover) between stages can be large. By including all mass transfer effects in the backmixing value, the same number of stages can be used for all extracted components no matter what their distribution coefficients. This greatly simplifies the calculations required when modeling multicomponent solvent extraction processes. Initial testing shows the new model to be better than either the Height of an Equivalent Theoretical Plate (HETP) or the Height of a Transfer Unit (HTU) method.
Date: December 8, 1989
Creator: Leonard, R. A.; Regalbuto, M. C.; Chamberlain, D. B. & Vandegrift, G. F.
Partner: UNT Libraries Government Documents Department

The kinetics of sulfation of calcium oxide

Description: Studies of the sulfation rate behavior show an initial fast rate followed by a rate decrease. This behavior has generally been interpreted as product layer diffusion limitations taking over after an initial kinetic rate regime. Many investigators tried to model this observed rate change. As pore diffusion was a limiting phenomenon in most of the experiments, authors have used several pore models to described this complication, more or less successfully. Product layer diffusivity has been assumed to be constant as conversion increased; however, there is no general agreement as to its value. In this work we are investigating the mechanism of this process with emphasis on measurement of product layer diffusivity and the surface reaction rate. Some additional experimental work was done to investigate the order and activation energy of the sulfation under different conditions. The effect of additives was studied again, by sprinkling some KCl or NaCl salt on top of partially reacted synthetic lime, in an effort to change the surface reaction rate rather than the diffusion rate.
Date: December 29, 1989
Creator: Sarofim, A. F. & Longwell, J. P.
Partner: UNT Libraries Government Documents Department

The Inevitable Universe---Parker-Rhodes' peculiar mixture of ontology and physics

Description: When asked to give a lecture on Parker-Rhodes' physics, I was somewhat non-plused. I almost replied What physics '' --- a point of view that Frederick expresses himself more than once in the book he was working on when he died. But that would be unjust. Whatever his view, I assert that the discovery of the Combinational Hierarchy is one of the most important discoveries'' --- or whatever you want to call it --- in physics made in this century. His calculation of the proton-electron mass ratio is also a fantastic result that we are still trying to come to grips with. And his insight into early cosmology --- what he called a cold big bang'' --- which appeared in an early version of the Theory of Indistinguishables, also had merit. His early universe is a lot closer to my own views now than I realized when I first encountered it. We will mention other insights as I go along. But his views are so different from those of anyone I know or knew, that I have decided to let him speak for himself by reading passages from his manuscript The Inevitable Universe, or TIU, which was still unpublished at the time of his death, and add a few comments on them.
Date: December 1, 1989
Creator: Noyes, H. P.
Partner: UNT Libraries Government Documents Department

Luminosity calculation

Description: The luminosity of the Tevatron collider was calculated. The data used for the calculation are the flying wire transverse beam profile and the SBD bunch profile. For the 900 GeV/c mini beta runs, the calculation was compared to the CDF luminosity monitor. The ratio of the calculation and C:BOLUMP is 0.95. 1 ref., 9 figs., 4 tabs.
Date: December 1, 1989
Creator: Hsueh, Shao-Yuan.
Partner: UNT Libraries Government Documents Department

The effect of chemical additives on the synthesis of ethanol

Description: The objective of this research is to elucidate the role of various chemical additives on ethanol synthesis over Rh- and Ni-based catalysts. Chemical additives used for this study will include S, P, Ag, Cu, Mn, and Na which have different lectronegativities. The effect of additives on the surface state of the catalysts, heat of adsorption of reactant molecules, reaction intermediates, reaction pathways, reaction kinetics, and product distributions is/will be investigated by a series of experimental studies of NO adsorption, reaction probing, study state rate measurement, and transient kinetic study. A better understanding of the role of additive on the synthesis reaction may allow us to use chemical additives to manipulate the catalytic properties of Rh- and Ni-based catalysts for producing high yields of ethanol from syngas.
Date: December 20, 1989
Creator: Chuang, S. S. C.
Partner: UNT Libraries Government Documents Department

Some global problems in gauge theories (Variations on a theme of Aharonov and Bohm)

Description: Several situations are discussed, in which the sort of global considerations made famous by Aharonov and Bohm in their discussion of the interaction of charged particles with magnetic flux tubes have important physical implications. It is argued that discrete gauge symmetries in the continuum make sense, and manifest themselves most clearly in Aharonov-Bohm type scattering of charged particles off string singularities. The existence of such discrete symmetries has important implications for the quantum mechanics of topologically non-trivial space-times in general and black holes in particular. It is argued that in the non-abelian case essentially new features arise, most notably that the symmetry group of the homogeneous ground state generally ceases to be globally defined in the presence of a string. When continuous rather than discrete symmetries are involved, a variety of fascinating and as yet poorly understood dynamical effects occur. Perhaps the most striking is a new form of string superconductivity, that exists for purely topological reasons, and is not well modeled by regarding the string as a superconducting wire. 8 refs., 2 figs.
Date: December 1, 1989
Creator: Wilczek, F.
Partner: UNT Libraries Government Documents Department

Effects of target size on the comparison of photon and charged particle dose distributions

Description: The work presented here is part of an ongoing project to quantify and evaluate the differences in the use of different radiation types and irradiation geometries in radiosurgery. We are examining dose distributions for photons using the Gamma Knife'' and the linear accelerator arc methods, as well as different species of charged particles from protons to neon ions. A number of different factors need to be studied to accurately compare the different modalities such as target size, shape and location, the irradiation geometry, and biological response. This presentation focuses on target size, which has a large effect on the dose distributions in normal tissue surrounding the lesion. This work concentrates on dose distributions found in radiosurgery, as opposed to those usually found in radiotherapy. 5 refs., 2 figs.
Date: December 1, 1989
Creator: Phillips, Mark H.; Frankel, Kenneth A.; Tjoa, Tom; Lyman, John T.; Fabrikant, Jacob I. & Levy, Richard P.
Partner: UNT Libraries Government Documents Department

Clinical results of stereotactic hellium-ion radiosurgery of the pituitary gland at Lawrence Berkeley Laboratory

Description: The first therapeutic clinical trial using accelerated heavy-charged particles in humans was performed at Lawrence Berkeley Laboratory (LBL) for the treatment of various endocrine and metabolic disorders of the pituitary gland, and as suppressive therapy for adenohypophyseal hormone-responsive carcinomas and diabetic retinopathy. In acromegaly, Cushing's disease, Nelson's syndrome and prolactin-secreting tumors, the therapeutic goal in the 433 patients treated has been to destroy or inhibit the growth of the pituitary tumor and control hormonal hypersecretion, while preserving a functional rim of tissue with normal hormone-secreting capacity, and minimizing neurologic injury. An additional group of 34 patients was treated for nonsecreting chromophobe adenomas. This paper discusses the methods and results of stereotactic helium-ion radiosurgery of the pituitary gland at Lawrence Berkeley Laboratory. 11 refs.
Date: December 1, 1989
Creator: Levy, R. P.; Fabrikant, Jacob I.; Lyman, J. T.; Frankel, K. A.; Phillips, M. H.; Lawrence, J. H. et al.
Partner: UNT Libraries Government Documents Department

Clinical-radiological evaluation of sequelae of stereotactic radiosurgery for intracranial arteriovenous malformations

Description: Stereotactic heavy-charged-particle Bragg peak radiosurgery has been used to treat 322 patients with surgically-inaccessible intracranial vascular malformations. (The clinical results of this method for the treatment of angiographically demonstrable arteriovenous malformations (AVMs) and angiographically occult vascular malformations (AOVMs) of the brain are described in separate reports of this symposium). The great majority of patients have had an uneventful post-treatment course with satisfactory health outcomes. However, several categories of delayed sequelae of stereotactic radiosurgery have been identified, involving the vascular structures essential for the integrity of the brain tissue and the brain parenchyma directly. These categories reflect both reaction to injury and to alterations in regional hemodynamic status, and include vasogenic edema, occlusion of functional vasculature, radiation necrosis, and local or remote effects on cerebral arterial aneurysms. 10 refs., 7 figs., 1 tab.
Date: December 1, 1989
Creator: Levy, R. P.; Fabrikant, J. I.; Frankel, K. A.; Phillips, M. H.; Steinberg, G. K.; Marks, M. P. et al.
Partner: UNT Libraries Government Documents Department

An automated procedure for covariation-based detection of RNA structure

Description: This paper summarizes our investigations into the computational detection of secondary and tertiary structure of ribosomal RNA. We have developed a new automated procedure that not only identifies potential bondings of secondary and tertiary structure, but also provides the covariation evidence that supports the proposed bondings, and any counter-evidence that can be detected in the known sequences. A small number of previously unknown bondings have been detected in individual RNA molecules (16S rRNA and 7S RNA) through the use of our automated procedure. Currently, we are systematically studying mitochondrial rRNA. Our goal is to detect tertiary structure within 16S rRNA and quaternary structure between 16S and 23S rRNA. Our ultimate hope is that automated covariation analysis will contribute significantly to a refined picture of ribosome structure. Our colleagues in biology have begun experiments to test certain hypotheses suggested by an examination of our program's output. These experiments involve sequencing key portions of the 23S ribosomal RNA for species in which the known 16S ribosomal RNA exhibits variation (from the dominant pattern) at the site of a proposed bonding. The hope is that the 23S ribosomal RNA of these species will exhibit corresponding complementary variation or generalized covariation. 24 refs.
Date: December 1, 1989
Creator: Winker, S.; Overbeek, R.; Woese, C. R.; Olsen, G. J. & Pfluger, N.
Partner: UNT Libraries Government Documents Department

Amorphous silicon detectors in positron emission tomography

Description: The physics of the detection process is studied and the performances of different Positron Emission Tomography (PET) system are evaluated by theoretical calculation and/or Monte Carlo Simulation (using the EGS code) in this paper, whose table of contents can be summarized as follows: a brief introduction to amorphous silicon detectors and some useful equation is presented; a Tantalum/Amorphous Silicon PET project is studied and the efficiency of the systems is studied by Monte Carlo Simulation; two similar CsI/Amorphous Silicon PET projects are presented and their efficiency and spatial resolution are studied by Monte Carlo Simulation, light yield and time characteristics of the scintillation light are discussed for different scintillators; some experimental result on light yield measurements are presented; a Xenon/Amorphous Silicon PET is presented, the physical mechanism of scintillation in Xenon is explained, a theoretical estimation of total light yield in Xenon and the resulting efficiency is discussed altogether with some consideration of the time resolution of the system; the amorphous silicon integrated electronics is presented, total noise and time resolution are evaluated in each of our applications; the merit parameters {epsilon}{sup 2}{tau}'s are evaluated and compared with other PET systems and conclusions are drawn; and a complete reference list for Xenon scintillation light physics and its applications is presented altogether with the listing of the developed simulation programs.
Date: December 1, 1989
Creator: Conti, M. & Perez-Mendez, V.
Partner: UNT Libraries Government Documents Department

Project plan for the decontamination and decommissioning of the Argonne National Laboratory Experimental Boiling Water Reactor

Description: In 1956, the Experimental Boiling Water Reactor (EBWR) Facility was first operated at Argonne National Laboratory (ANL) as a test reactor to demonstrate the feasibility of operating an integrated power plant using a direct cycle boiling water reactor as a heat source. In 1967, ANL permanently shut down the EBWR and placed it in dry lay-up. This project plan presents the schedule and organization for the decontamination and decommissioning of the EBWR Facility which will allow it to be reused by other ANL scientific research programs. The project total estimated cost is $14.3M and is projected to generate 22,000 cubic feet of low-level radioactive waste which will be disposed of at an approved DOE burial ground. 18 figs., 3 tabs.
Date: December 1, 1989
Creator: Boing, L. E.
Partner: UNT Libraries Government Documents Department

ITER (International Thermonuclear Experimental Reactor) R and D breeder blanket materials

Description: The International Thermonuclear Experimental Reactor (ITER) activity includes specific R D in critical areas to support the ITER design. Several of the critical tasks defined as part of the ITER validating R D are materials related. This paper presents a summary of the breeder/blanket materials related R D conducted by the four participating parties; viz., European Community, Japan, Soviet Union and the United States. The current effort includes several subtasks in each of the following four task areas: ceramic breeder materials; lead-lithium breeder; aqueous salt solutions; and neutron multiplier materials. The objective and scope of each subtask is states. Although this work was initiated in late 1988, important results have been obtained in all four areas. The work on ceramic breeders includes properties measurements, compatibility studies, and tritium recovery experiments with Li{sub 2}O and selected ternary ceramics. Investigations on the lead-lithium breeder have focused primarily on properties, compatibility, and tritium extraction from the 17Li-83Pb eutectic alloy. The work on the aqueous salt breeders includes corrosion, solution chemistry, and radiolysis effects in a radiation environment. Investigations defined under the neutron multiplier task are focused on beryllium; however, lead in the lithium lead alloy also serves as a neutron multiplier. The schedule and planned future work in each area are summarized. 1 refs., 6 tabs.
Date: December 1, 1989
Creator: Smith, D. L.; Daenner, W.; Kalinin, G. & Yoshida, H.
Partner: UNT Libraries Government Documents Department

Geothermal Progress Monitor report No. 11

Description: This issue of the Geothermal Progress Monitor (GPM) is the 11th since the inception of the publication in 1980. It continues to synthesize information on all aspects of geothermal development in this country and abroad to permit identification and quantification of trends in the use of this energy technology. In addition, the GPM is a mechanism for transferring current information on geothermal technology development to the private sector, and, over time, provides a historical record for those interested in the development pathway of the resource. In sum, the Department of Energy makes the GPM available to the many diverse interests that make up the geothermal community for the multiple uses it may serve. This issue of the GPM points up very clearly how closely knit many of those diverse interests have become. It might well be called an international issue'' since many of its pages are devoted to news of geothermal development abroad, to the efforts of the US industry to participate in overseas development, to the support given those efforts by federal and state agencies, and to the formation of the International Geothermal Association (IGA). All of these events indicate that the geothermal community has become truly international in character, an occurrence that can only enhance the future of geothermal energy as a major source of energy supply worldwide. 15 figs.
Date: December 1, 1989
Partner: UNT Libraries Government Documents Department

A demonstration of the applicability of implementing the enhanced Remedial Action Priority System (RAPS) for environmental releases

Description: The Remedial Action Priority System (RAPS) and the Multimedia Environmental Pollutant Assessment System (MEPAS) were developed to prioritize problems associated with potential releases of hazardous chemical and radioactive materials in a scientific and objective manner based on limited site information. This report documents the model testing efforts of the RAPS/MEPAS methodology for the atmospheric, surface water, groundwater, and exposure components. Comparisons are given of model outputs with measured data at three sites: the US Department of Energy's Mound facility in Ohio and Hanford facility in Washington, and a chromium-cadmium plating site in New York. The results show that the simulated magnitudes, spacial and temporal trends, and distributions of contaminants corresponded well with the measured data. 25 refs., 86 figs., 26 tabs.
Date: December 1, 1989
Creator: Whelan, G.; Droppo, J. G. Jr.; Strenge, D. L.; Walter, M. B. & Buck, J. W.
Partner: UNT Libraries Government Documents Department