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Design of a Precast Concrete Stay-in-Place Forming System for Lock Wall Rehabilitation: Report describing the design of forming a system to use pre-cast concrete for rehabilitating damaged walls in locks, as a way to prevent problems with cracking in replacement air-entrained concrete used in standard methods.
Inclusive. eta. production in. tau. decays: We have searched for inclusive eta production in tau decays using a sample of 2553 events of e{sup +}e{sup minus} {yields} {tau}{sup +}{tau}{sup minus} in the one-three topology. The data were taken with the High Resolution Spectrometer at {radical}s = 29 GeV. Our results are based on an analysis of the {pi}{sup +}{pi}{sup minus} invariant mass spectrum to find the narrow peak resulting from the decay sequence {tau} {yields} {eta}x and {eta} {yields} {pi}{sup +}{pi}{sup minus}{pi}{degree}. No clear peak is observed and a 90% confidence upper limit on the process {tau} {yields} {eta}x of 2.1% is found. For decays {tau} {yields} {eta}{eta}x the 90% confidence upper limit is 1.3%. Our best limit on {tau} {yields} {eta}{eta}x is obtained from tau decay to five charged particles with a 90% confidence level upper limit of 0.5%.
Production of eta mesons in e/sup +/e/sup -/ annihilations at. sqrt. s = 29 GeV: Data from e/sup +/e/sup -/ annihilations at 29 GeV have been used to measure the production and fragmentation of eta mesons. The signal is observed in the eta ..-->.. ..gamma gamma.. decay channel. The fragmentation function for p/sub eta/ > 1.5 GeV/c agrees well with the shapes predicted by both the Lund and Webber models. However, the mean multiplicity is measured to be < n/sub eta/ > = 0.37 +- 0.08 eta mesons per hadronic annihilation event, which is significantly lower than the values predicted by either model. 6 refs., 2 figs., 1 tab.
Search for D/sup *//sup 0/. -->. D/sup +/. pi. /sup -/: We report on a search for the decay mode D/sup *//sup 0/(2007) ..-->.. D/sup +/..pi../sup -/ using the High Resolution Spectrometer at PEP. Although this decay is kinematically forbidden for the central mass value, it can occur through the natural width of the D/sup *//sup 0/. The D/sup +/ was reconstructed in the K/sup -/..pi../sup +/..pi../sup +/ decay mode. The mass difference distribution (K/sup -/..pi../sup +/..pi../sup +/..pi../sup +/) - (K/sup -/..pi../sup +/..pi../sup -/), which shows no threshold enhancement, leads to a preliminary upper limit on the branching ratio of B/sub r/(D/sup *//sup 0/ ..-->.. D/sup +/..pi../sup -/) < 15% at 90% CL. This, in turn, corresponds to an upper limit on the D/sup *//sup 0/ width of 1.5 MeV/c/sup 2/ at 90% CL. 4 refs., 3 figs.
Mechanical design of a large bore quadrupole triplet magnet: The mechanical design and construction of a 1 meter bore, low gradient quadrupole triplet is described. The magnet will be used for focussing a proton beam in accelerator studies of neutral particle at the Los Alamos National Laboratory. A significant feature of this magnet design is the precision location of the coil conductors within the steel yoke tube. Each of the quadrupole coils have been fabricated from water cooled aluminum conductor, wound in a cosine 2-theta geometry. The conductor bundles have been wound to a positional accuracy within +-0.050 cm which was required to reduce the harmonic content to less than 0.04% of the quadrupole field. Important aspects of the design, construction and assembly are described.
Measurement of Energy and Charged Particle Emission in the Central Rapidity Region from O + A and p + A collisions at 14. 5 GeV/c per Nucleon and Preliminary Results from Si + A collisions: The first data from a 160 beam of total energy 232 GeV at the BNL Tandem-AGS are discussed. Preliminary results from a /sup 28/Si beam of total energy 406 GeV are also shown. The full complement of E-802, including a magnetic spectrometer, was used for the /sup 28/Si measurement. A different experimental arrangement was used for 160. Comparison measurements with proton beams are presented for both configurations. 12 refs., 12 figs.
Elastic Scattering of Muon Neutrinos at BNL: In this paper measurement of the purely leptonic reactions: nu/sub ..mu../e ..-->.. nu/sub ..mu../e and anti nu/sub ..mu../e ..-->.. anti nu/sub ..mu../e, and the semileptonic reactions: nu/sub ..mu../p ..-->.. nu/sub ..mu../p and anti nu/sub ..mu../p ..-->.. anti nu/sub ..mu../p are presented and discussed in terms of the standard model. The data also places limites of interest on the magnitudes of a possible neutrino charge radius and a neutrino magnetic moment.
Preparing the radiation protection worker to meet multiple needs: At the Oak Ridge National Laboratory (ORNL) the radiation protection worker aids in protecting personnel and their surrounding environment from the hazards of radiation. These individuals use their technical knowledge, skills, and abilities to survey and monitor various project-related activities. They must also provide guidance in project design, development, and implementation. These combined efforts assure that protective measures are taken in accordance with applicable standards. The ORNL performance-based training program enhances the skills of the worker. The program incorporates job specific information on the diverse facilities and activities monitored with basic fundamentals of radiation protection. Successful completion of this program includes passing both a qualification exam and an on-the-job skills review. This paper details the structure of such a program and explains the strategies taken to reach the program's goals. 4 refs., 2 tabs.
Experience in using workstations as hosts in an accelerator control environment: A new control system has been used for light ion acceleration at the Alternating Gradient Synchrotron (AGS). The control system uses Apollo workstations in the dual role of console hardware computer and controls system host. It has been found that having a powerful dedicated CPU with a demand paging virtual memory OS featuring strong interprocess communication, mapped memory shared files, shared code, and multi-window capabilities, allows us to provide an efficient operation environment in which users may view and manage several control processes simultaneously. The same features which make workstations good console computers also provide an outstanding platform for code development. The software for the system, consisting of about 30K lines of ''C'' code, was developed on schedule, ready for light ion commissioning. System development is continuing with work being done on applications programs.
Sequence dependent structure and thermodynamics of DNA oligonucleotides and polynucleotides: uv melting and NMR (nuclear magnetic resonance) studies: Thermodynamic parameters for double strand formation have been measured for the twenty-five DNA double helices made by mixing deoxyoligonucleotides of the sequence dCA/sub 3/XA/sub 3/G with the complement dCT/sub 3/YT/sub 3/G. Each of the bases A, C, G, T, and I (I = hypoxanthine) have been substituted at the positions labeled X and Y. The results are analyzed in terms of nearest neighbors. At higher temperatures the sequences containing a G)centerreverse arrowdot)C base pair become more stable than those containing only A)centerreverse arrowdot)T. All molecules containing mismatcher are destabilized with respect to those with only Watson-Crick pairing, but there is a wide range of destabilization. Large neighboring base effects upon stability were observed. For example, when (X, Y) = (I, A), the duplex is eightfold more stable than when (X, Y) = (A, I). Independent of sequence effects the order of stabilities is: I)centerreverse arrowdot)C )succ) I)centerreverse arrowdot) A)succ) I)centerreverse arrowdot)T approx. I)centerreverse arrowdot)G. All of these results are discussed within the context of models for sequence dependent DNA secondary structure, replication fidelity and mechanisms of mismatch repair, and implications for probe design. The duplex deoxyoligonucleotide d(GGATGGGAG))centerreverse arrowdot)d(CTCCCATCC) is a portion of the gene recognition sequence of the protein transcription factor IIIA. The crystal structure of this oligonucleotide was shown to be A-form The present study employs Nuclear Magnetic Resonance, optical, chemical and enzymatic techniques to investigate the solution structure of this DNA 9-mer. (157 refs., 19 figs., 10 tabs.
Sodium Waste Technology : a Summary Report: The Sodium Waste Technology (SWT) Program was established to resolve long-standing issues regarding disposal of sodium-bearing waste and equipment. Comprehensive SWT research programs investigated a variety of approaches for either removing sodium from sodium-bearing items, or disposal of items containing sodium residuals. The most successful of these programs was the design, test, and the production operation of the Sodium Process Demonstration Facility at ANL-W. The technology used was a series of melt-drain-evaporate operations to remove nonradioactive sodium from sodium-bearing items and then converting the sodium to storable compounds.
Sodium waste technology: A summary report. [Melt-drain-evaporation-calcination (MEDEC)]: The Sodium Waste Technology (SWT) Program was established to resolve long-standing issues regarding disposal of sodium-bearing waste and equipment. Comprehensive SWT research programs investigated a variety of approaches for either removing sodium from sodium-bearing items, or disposal of items containing sodium residuals. The most successful of these programs was the design, test, and the production operation of the Sodium Process Demonstration Facility at ANL-W. The technology used was a series of melt-drain-evaporate operations to remove nonradioactive sodium from sodium-bearing items and then converting the sodium to storable compounds.
Fast Energy and Energy Spectrum Feedback in the SLC Linac: The energies and energy spectra of the positron and electron beams emerging from the SLC Linac must be carefully maintained so that the beams can be transported through the Arcs to the Final Focus without phase space dilution and also to specify the collision energy. A fastback system has been designed and constructed to control these parameters. The energies and energy spectra are measured nondestructively using position monitors and synchrotron radiation width monitors. The controls consist of rf phases in the Damping Rings, SLED timing, and rf amplitude. Theoretical aspects of the feedback process, algorithms, and operational experience are discussed.
The development of a selective ruthenium catalyst: A micelle technique was developed for preparing supported catalysts with different size ruthenium particles. Ruthenium was stabilized on the support, light ends make was minimized and activity was maximized by adjusting the ruthenium particle size and the metal-support interaction. The most promising catalysts consisted of 10--15 nm ruthenium particles on an alumina-titania support and 4--6 nm ruthenium particles on an alumina support. Stability improvement was determined to be the major catalyst developmental need. Work during the next quarter will focus on the development of a stable ruthenium catalyst.
The development of a selective ruthenium catalyst. Technical progress report, October 1, 1987--December 31, 1987: A micelle technique was developed for preparing supported catalysts with different size ruthenium particles. Ruthenium was stabilized on the support, light ends make was minimized and activity was maximized by adjusting the ruthenium particle size and the metal-support interaction. The most promising catalysts consisted of 10--15 nm ruthenium particles on an alumina-titania support and 4--6 nm ruthenium particles on an alumina support. Stability improvement was determined to be the major catalyst developmental need. Work during the next quarter will focus on the development of a stable ruthenium catalyst.
Instabilities of higher dimensional compactifications: Various schemes for cosmological compactification of higher dimensional theories are considered. Possible instabilities which drive the ground state with static internal space to de Sitter-like expansion of all dimensions are discussed. These instabilities are due to semiclassical barrier penetration and classical thermal fluctuations. For the case of the ten dimensional Chapline-Manton action, it is possible to avoid such difficulties by balancing one-loop Casimir corrections against monopole contributions from the field strength H/sub MNP/ and fermionic condensates. 10 refs.
IR laser excitation in molecules: Chaos and diffusive energy growth: After a short review of a generic vibrational model of ir multiple-photon excitation, the model is generalized to include rotations. It is shown that the combination of chaotic dynamics and rotational averaging leads to fluence-dependent absorption which removes the sensitivity of the results to model-dependent parameters. The classical rotation-vibration dynamics observed in this model correlate very well with quantum intuition based on a molecule's P, Q, and R-branch structure and on the red-shift of the vibrational absorption with excitation. The implication of these results for MPE experiments is discussed.
Nuclear breakup and particle densities in 200 A GeV - /sup 16/O interactions with emulsion nuclei: Experiment EMU-01 makes use of emulsion chambers and conventional stacks to study the interactions in matter of 200 A GeV /sup 16/O nuclei accelerated at the CERN SPS. Projectile fragmentation is compatible with such interactions of /sup 16/O nuclei at 2 A GeV, indications of limiting fragmentation. Particle production is examined via high precision pseudo-rapidity distributions. Energy densities up to about 3 GeVfm/sup 3/ are observed in central /sup 16/O + Ag(Br) interactions. Pseudo-rapidity density distributions and fluctuations are well reproduced by the MC model Pritiof, although the existence of new and unknown sources of density fluctuations are not excluded by the data. 7 refs., 7 figs.
Boundary-projection acceleration: A new approach to synthetic acceleration of transport calculations: We present a new class of synthetic acceleration methods which can be applied to transport calculations regardless of geometry, discretization scheme, or mesh shape. Unlike other synthetic acceleration methods which base their acceleration on P1 equations, these methods use acceleration equations obtained by projecting the transport solution onto a coarse angular mesh only on cell boundaries. We demonstrate, via Fourier analysis of a simple model problem as well as numerical calculations of various problems, that the simplest of these methods are unconditionally stable with spectral radius less than or equal toc/3 (c being the scattering ratio), for several different discretization schemes in slab geometry. 28 refs., 4 figs., 3 tabs.
Marker Development: This report is to discuss the marker development for radioactive waste disposal sites. The markers must be designed to last 10,000 years, and place no undue burdens on the future generations. Barriers cannot be constructed that preclude human intrusion. Design specifications for surface markers will be discussed, also marker pictograms will also be covered.
A general topology, Godunov method: A numerical technique that utilizes a general topology mesh is described. The method employs the arbitrary Lagrangian-Eulerian procedure and explicit, finite-volume, Godunov numerics. Material interfaces are resolved to eliminate fictitious mixing and nonphysical shear impedance. Cell-centered variables, including velocity, are used to provide consistent control volumes for the advection of mass, momentum, and energy, and to allow arbitrary slip between material regions. The computational mesh is composed of arbitrary polygonal cells. The constraint of a fixed logical connectivity for the mesh is removed. Consequently, geometrical mesh limitations, which are responsible for inaccuracies and code failure during the evolution of region boundaries, are absent. Arbitrary boundaries can be resolved, and the mesh is capable of changing smoothly and rapidly from regions of high to low resolution. Lack of a coherent mesh orientation minimizes numerical anisotropy. A mesh rezoning approach, based on a dual triangulation and coupled with a global remapping algorithm, allows the mesh to evolve dynamically. 9 refs., 6 figs.
The Mark III Vertex Chamber: The design and construction of the new Mark III vertex chamber is described. Initial tests with cosmic rays prove the ability of track reconstruction and yield triplet resolutions below 50 ..mu..m at 3 atm using argon/ethane (50:50). Also performed are studies using a prototype of a pressurized wire vertex chamber with 8 mm diameter straw geometry. Spatial resolution of 35mm was obtained using dimethyl ether (DME) at 1 atm and 30 ..mu..m using argon/ethane (50/50 mixture) at 4 atm. Preliminary studies indicate the DME to adversely affect such materials as aluminized Mylar and Delrin.
Emittance growth in rippled solenoidal magnetic fields: Emittance growth results due to accelerating gaps, and magnetic field gaps in induction accelerators. The analytic technique previously used to study electric field induced emittance growth for immersed source beams is extended to include solenoid fringing field effects in the present work. These results have application to industrial induction accelerators and to high brightness Free Electron Laser drivers. 1 ref., 2 figs.
Status of the silicon strip vertex detector for the Mark II experiment at the SLC: We are constructing a silicon strip vertex detector to be used in the Mark II detector in the study of Z/sup 0/ decays at the SLAC Linear Collider. The status of the project, including the performance of the individual silicon detector modules, is presented. 6 refs., 8 figs., 2 tabs.
Report to users of ATLAS (Argonne Tandem-Line Accelerator System): The operation and development of ATLAS are reported, including accelerator improvements. Particularly noted is an upgrade to extend the mass range of projectiles up to uranium and to increase the beam intensity by at least two orders of magnitude for all ions. Meetings are discussed, particularly of the Program Advisory Committee and the User Group Executive Committee. Some basic information is provided for users planning to run experiments at ATLAS, including a table of beams available. The data acquisition system for ATLAS, DAPHNE, is discussed, as are the following experimental facilities: the Argonne-Notre Dame Gamma Ray Facility, a proposal submitted for constructing a large-acceptance Fragment Mass Analyzer. Brief summaries are provided of some recent experiments for which data analysis is complete. Experiments performed during the period from June 1, 1986 to January 31, 1987 are tabulated, providing the experiment number, scientists, institution, experiment name, number of days, beam, and energy. (LEW)
Nuclide migration from areal sources into a fracture: This document shows analytic solutions to the problem of hydrogeologic transport of radionuclides released from finite areal sources into a planar fracture. It illustrates the solutions through numerical and graphical displays of the spatial and temporal distribution of the radionuclides as a result of advection in the fracture, transverse dispersion and surface sorption, as well as diffusion into and sorption in the rock matrix. The numerical illustrations indicate that sufficient distances away from the sources equivalent single sources give acceptable approximations. 2 refs., 3 figs.
A Search for Heavy Neutrino Decays in a Neutrino Beam: Decay of heavy neutrinos ..nu../sub H/ ..-->.. ..nu..l..mu..e(l = e, ..mu..) has been searched for in the Brookhaven Alternting Gradient Synchrotron wide-band neutrino beam. Since no significant excess of such events was found, upper limits on the neutrino mixing matrix elements, absolute value of U/sub eH//sup 2/ and absolute value of U/sub ..mu..H//sup 2/ were obtained for the mass range of 180 to 500 MeV.
Measurement of the Photon Structure Function F/sub 2//sup gamma/(x,Q/sup 2/) Between 10 less than or equal to Q/sup 2/ less than or equal to 60 GeV/sup 2/: We present a measurement of the photon structure function F/sub 2//sup ..gamma../ in the reaction ee..-->..eeX for Q/sup 2/ in the range 10 < Q/sup 2/ < 60 GeV/sup 2/, using 285 multihadron events obtained with the TPC/Two-Gamma detector at PEP. The data have been corrected for detector effects using a regularized unfolding procedure. Using our previous low Q/sup 2/ measurements to estimate the hadronic component, we perform a QCD analysis at high Q/sup 2/ within the context of the regularisation scheme of Antoniadis and Grunberg. We obtain rather safe bounds on the value of the QCD scale parameter of 119 +- 34 < ..lambda../sub M-bar S-bar/ < 215 +- 55 MeV.
Latency differences and effects of selective attention to gratings in the central and right visual fields: II: The goals were to examine the temporal sequence in which visual information (such as visual field, spatial frequency) are processed and to determine whether different neural sources are activated when such features are attended versus not attended. These issues are basic to current models of visual selective attention. 10 refs., 4 figs.
Plan for glass waste form testing for NNWSI [Nevada Nuclear Waste Storage Investigations]: The purpose of glass waste form testing is to determine the rate of release of radionuclides from breached glass waste containers. This information will be used to qualify glass waste forms with respect to the release requirements. It will be the basis of the source term from glass waste for repository performance assessment modeling. This information will also serve as part of the source term in the calculation of cumulative releases after 100,000 years in the site evaluation process. It will also serve as part of the source term input for calculation of cumulative releases to the accessible environment for 10,000 years after disposal, to determine compliance with EPA regulations. This investigation will provide data to resolve information needs. Information about the waste forms which is provided by the producer will be accumulated and evaluated; the waste form will be tested, properties determined, and mechanisms of degradation determined; and models providing long-term evaluation of release rates designed and tested. 23 refs.
Hydrogen speciation in hydrated layers on nuclear waste glass: The hydration of an outer layer on nuclear waste glasses is known to occur during leaching, but the actual speciation of hydrogen (as water or hydroxyl groups) in these layers has not been determined. As part of the Nevada Nuclear Waste Storage Investigations Project, we have used infrared spectroscopy to determine hydrogen speciations in three nuclear waste glass compositions (SRL-131 & 165, and PNL 76-68), which were leached at 90{sup 0}C (all glasses) or hydrated in a vapor-saturated atmosphere at 202{sup 0}C (SRL-131 only). Hydroxyl groups were found in the surface layers of all the glasses. Molecular water was found in the surface of SRL-131 and PNL 76-68 glasses that had been leached for several months in deionized water, and in the vapor-hydrated sample. The water/hydroxyl ratio increases with increasing reaction time; molecular water makes up most of the hydrogen in the thick reaction layers on vapor-phase hydrated glass while only hydroxyl occurs in the least reacted samples. Using the known molar absorptivities of water and hydroxyl in silica-rich glass the vapor-phase layer contained 4.8 moles/liter of molecular water, and 0.6 moles water in the form hydroxyl. A 15 {mu}m layer on SRL-131 glass formed by leaching at 90{sup 0}C contained a total of 4.9 moles/liter of water, 2/3 of which was as hydroxyl. The unreacted bulk glass contains about 0.018 moles/liter water, all as hydroxyl. The amount of hydrogen added to the SRL-131 glass was about 70% of the original Na + Li content, not the 300% that would result from alkali=hydronium ion interdiffusion. If all the hydrogen is then assumed to be added as the result of alkali-H{sup +} interdiffusion, the molecular water observed may have formed from condensation of the original hydroxyl groups.
CSDP: The seismology of continental thermal regimes: Final report for period April 1, 1986-April 1, 1987: This report describes progress in the study of both wave propagation in complex structures and source mechanism of geothermal seismic events. The following work was accomplished in the past one-year period: (1) interpretation of long-period events observed at Mt. St. Helens and at the Fenton Hill hot-dry-rock experimental site in terms of seismic radiation from a fluid-filled crack; (2) interpretation of teleseismic data collected in and near the Valles caldera in terms of a model with irregular topography, caldera fill, and magma chamber; (3) interpretation of VSP (Vertical Seismic Profiling) data from the Oroville fault zone by ray tracing and polarization calculation for P, SV, and SH waves in heterogeneous and anisotropic media containing aligned fluid-filled and/or dry cracks; and (4) development of a new powerful method for calculating seismic motions in media with irregular topography and interfaces by the superposition of Gaussian Beams.
Safeguards Effectiveness Evaluations in Safeguards Planning: This paper describes analytic tools we developed to quantify the effectiveness of safeguards against theft of special nuclear material by insiders. These tools help identify vulnerabilities in existing safeguards, suggest potential improvements, and help assess the benefits of these upgrades prior to implementation. Alone, these tools are not sufficient for safeguards planning, since the cost of implementing all suggested upgrades almost always exceeds the available resources. This paper describes another tool we developed to allow comparsion of benefits of various upgrades to identify those upgrade packages that achieve the greatest improvement in protection for a given cost and to provide a priority ranking among cost-effective packages, thereby helping decision-makers select the upgrades to implement and highlight the mount of residual risk. 5 refs., 3 figs.
Tactical Vulnerability Assessment Training Program: The Department of Energy sponsors a 9-day training program for individual who are responsible for evaluating and planning safeguards systems and for preparing DOE Master and Security Agreements (MSSAs). These agreements between DOE headquarters and operations offices establish required levels of protection. The curriculum includes: (1) the nature of potential insider and outsider threats involving theft or diversion of special nuclear material, (2) use of computerized tools for evaluating the effectiveness of physical protection and material control and acoountability systems, and (3) methods for analyzing the benefits and costs of safeguards improvements and for setting priorities among proposed upgrades. The training program is varied and highly interactive. Presentations are intermixed with class discussions and ''hands-on'' analysis using computer tools. At the end of the program, participants demonstrate what they have learned in a two-and-one-half day ''field excercise,'' which is conducted on a facility scale-model. The training programs has been conducted six times and has been attended by representatives of all DOE facilities. Additional sessions are planned at four-month intervals. This paper describes the training program, use of the tools in preparing MSSAs for various DOE sites, and recent extensions and refinements of the evaluation tools.
Cosmology for high energy physicists: The standard big bang model of cosmology is presented. Although not perfect, its many successes make it a good starting point for most discussions of cosmology. Places are indicated where well understood laboratory physics is incorporated into the big bang, leading to successful predictions. Much less established aspects of high energy physics and some of the new ideas they have introduced into the field of cosmology are discussed, such as string theory, inflation and monopoles. 49 refs., 5 figs.
Fluidized-Bed Retorting of Colorado Oil Shale: Topical Report.: In support of the research program in converting oil shale into useful forms of energy, the US Department of Energy is developing systems models of oil shale processing plants. These models will be used to project the most attractive combination of process alternatives and identify future direction for R and D efforts. With the objective of providing technical and economic input for such systems models, Foster Wheeler was contracted to develop conceptual designs and cost estimates for commercial scale processing plants to produce syncrude from oil shales via various routes. This topical report summarizes the conceptual design of an integrated oil shale processing plant based on fluidized bed retorting of Colorado oil shale. The plant has a nominal capacity of 50,000 barrels per operating day of syncrude product, derived from oil shale feed having a Fischer Assay of 30 gallons per ton. The scope of the plant encompasses a grassroots facility which receives run of the mine oil shale, delivers product oil to storage, and disposes of the processed spent shale. In addition to oil shale feed, the battery limits input includes raw water, electric power, and natural gas to support plant operations. Design of the individual processing units was based on non-confidential information derived from published literature sources and supplemented by input from selected process licensors. The integrated plant design is described in terms of the individual process units and plant support systems. The estimated total plant investment is similarly detailed by plant section and an estimate of the annual operating requirements and costs is provided. In addition, the process design assumptions and uncertainties are documented and recommendations for process alternatives, which could improve the overall plant economics, are discussed.
Advances in inherently conducting polymers: The discovery of polyacetylene as the prototype material led to extensive research on its synythesis and characterization. The techniques that emerged as the most important and promising ones are those that dealt with molecular orientation and that resulted in conductivities almost as high as that of copper. The study of dozens of other materials followed. Interest in conducting polymers stems from their nonclassical optical and electronic properties as well as their potential technological applications. However, some of the factors currently limiting their use are the lack of long-term stability and the need to develop conventional low-cost techniques for easy processing. Therefore, research was extended toward solving these problems, and progress has been recently made in that direction. The synthesis of new materials such as stable and easily processable alkylthiophenes, water-soluble polymers, and multicomponent systems, including copolymers and composites, constitutes an important step forward in the area of synthetic metals. However, a full understanding of materials chemistry and properties requires more work in the years to come. Although, few small-scale applications have proven to be successful, long-term stability and applicability tests are needed before their commercial use becomes reality.
Molecular and supramolecular orientation in conducting polymers: Intrinsic anisotropy in electrical and optical properties of conducting polymers constitutes a unique aspect that derives ..pi..-electron delocalization along the polymer backbone and from the weak inter-chain interaction. To acquire such an intrinsic property, conducting polymers have to be oriented macroscopically and microscopically (at the chain level). A review of the various techniques, including stretch-alignment of the polymer and of precursor polymers, polymerization in ordered media, i.e., in a liquid crystal solvent, and synthesis of liquid crystalline conducting polymers will be given. 29 refs.
Conducting hybrid polymeric systems: The studies took advantage of the opportunities offered by copolymerization for gaining insight into electrical conduction, morphology, phase separation, polymer-polymer interfaces, and solubility. Copolymerization is technologically important for it allows one to tailor-make products with specifically desired properties. However, the utility of copolymerization involving conjugated, rigid components could be different from that of conventional polymers. This paper is focused on the synthesis and properties of various materials: Rod-coil systems such as polyisoprene/polyacetylene diblock copolymers (resonance raman and small angle neutron scattering studies correlated to conductivity); and alternating copolymers such as poly (arylpyrroles) (electrochemical synthesis and characterization). 8 refs., 4 figs.
Improved input representation for enhancement of neural network performance: The performance of an associate memory network depends significantly on the representation of the data. For example, it has already been recognized that bipolar representation of neurons with -1 and +1 states out- perform neurons with on and off states of +1 and 0 respectively. This paper will show that a simple modification of the pattern vector to have zero bias will provide even more significant increase for the performance of an associative memory network. The higher order algorithm is used for the numerical simulation studies of this paper. To the lowest order this algorithm reduces to the Hopfield model for auto-associative memory and the bidirectional associative memory (BAM) for hetero-associative memory model respectively. 16 refs., 4 figs., 1 tabs.
San Ignacio (La Tembladera) geothermal site, Departamento de Francisco Morazan, Honduras, Central America: Geological field report: The San Ignacio (La Tembladera) geothermal site is located on the north side of the Siria Valley, Departamento de Francisco Morazan, near the village of Barrosa. Hot springs are located along a northwest-trending fault scarp at the edge of the valley and along north-trending faults that cross the scarp. The rocks in the area are primarily Paleozoic metamorphic rocks, overlain by patches of Tertiary Padre Miguel Group tuffs and alluvial deposits. Movement probably occurred along several faults during latest Tertiary and possibly early Quaternary times. Four spring areas were mapped. Area 1, the largest, is associated with a sinter mound and consists of 40 spring groups. About half of the springs, aligned along a north-south trend, are boiling. Area 2 is a small sinter mound with several seeps. Area 3 consists of a group of hot and boiling springs aligned along a north-trending fault. The springs rise through fractured schists and a thin cover of alluvium. Area 4 is located at the intersection of several faults and includes one of the largest boiling springs in the area.
AGS preinjector improvement: In 1984, a polarized H/sup -/ source was installed to permit the acceleration of polarized protons in the AGS, using a low current, 750 keV RFQ Linear Accelerator as the preinjector. This RFQ was designed by LANL and has proved to be quite satisfactory and reliable. In order to improve the reliability and simplify maintenance of the overall AGS operations, it has been decided to replace one of the two 750 keV Cockcroft-Waltons (C-W) with an RFQ. The design of a new high current RFQ has been carried out by LBL and is also being constructed there. This paper describes the preinjector improvement project, centered around that RFQ, which is underway at BNL.
H/sup -/ source and beam transport experiments for a new RFQ: A new RFQ preinjector is being built for the 200 MeV Linac at the AGS. For injection into this RFQ, a symmetric emittance has been obtained from a circular aperture magnetron H/sup -/ source. Transport studies are beginning to address possible problems with space charge or instabilities in the 35 keV line. A volume H/sup -/ source is being tested as an eventual replacement for the magnetron.
State of the art in polarized proton sources: Present day polarized H/sup +/ and H/sup -/ ion sources are reviewed by describing the performance of sources representative of each of the techniques being used. New ideas for producing higher intensities are then mentioned. Presently, pulsed H/sup +/-vector currents in the milliampere range, and H/sup -/-vector currents of hundreds of ..mu..A's, can be obtained.
The relation of solar wind structure to hydromagnetic discontinuities: High resolution ISEE-3 data have been used to examine the relative abundances of tangential (TD) vs rotational (RD) discontinuities in different types of solar wind flow. Three types of flow were examined; flow from coronal holes, sector boundary flow and transient flow. It has been found that coronal hole flow has substantially more discontinuities and a greater ratio of RD's to TD's than do the other types of flow. Discontinuities are least frequent in transient flows characterized by bidirectional streaming of electrons. This leads us to the conclusion that meaningful studies of the velocity dependence of the rates of occurrence of different types of discontinuities must take the type of flow (coronal hole versus transient) into account. 7 refs., 3 figs., 1 tab.
Rcra (Resource Conservation and Recovery Act) Waste Oversight: Lead: Historically, in the nuclear industry, water, concrete, steel, and lead have been common materials used for radiation shielding purposes. Lead, a high-density material, is a very effective shield for gamma radiation and has been utilized extensively at the Oak Ridge National Laboratory (ORNL) in association with radioisotope production and nuclear research. During these activities, lead became an inherent part of the radioactive waste and was disposed of in massive quantities by land burial.
An ion beam simulation of the swelling of U/sub 3/Si: Uranium intermetallics are under consideration as possible low-enrichment reactor fuels. These materials divide into two classes with regard to dimensional stability during their service lifetime: those which suffer extreme dimensional growth and those which do not. It has been suggested that the rapid-swelling materials are those that become glassy under irradiation while the low-swelling materials are those that remain crystalline. The structural and dimensional stabilities of U/sub 3/Si (depleted uranium) have been investigated as a function of temperature during Kr irradiation by in situ HVEM observations. Below 550/sup 0/K, this material becomes glassy during 1.0 MeV Kr irradiation. Prolonged irradiation at 475/sup 0/K also leads to rapid darkening of the TEM bright field image of the specimen, growth of the initial perforation at rates which far exceed those due to sputtering, and formation of additional thin areas and holes. Irradiation at 615/sup 0/K does not result in observable image darkening or rapid growth of the initial perforation. After 2 x 10/sup 20/ Kr m/sup -2/, the crystalline material irradiated at 615/sup 0/K is stabilized against subsequent ion-irradiation-induced amorphization and growth at 475/sup 0/K. Similarly, after 2 x 10/sup 20/ Kr m/sup -2/ at 475/sup 0/K, the glassy phase persists at 620/sup 0/K under additional Kr irradiation, and the rapid growth continues. The mechanism of the irradiation-induced growth of the glassy material does not involve gas precipitation but rather may involve deformation by viscous flow assisted by the defects generated during irradiation. 12 refs., 3 figs.
Conventional power sources for colliders: At SLAC we are developing high peak-power klystrons to explore the limits of use of conventional power sources in future linear colliders. In an experimental tube we have achieved 150 MW at 1 ..mu..sec pulse width at 2856 MHz. In production tubes for SLAC Linear Collider (SLC) we routinely achieve 67 MW at 3.5 ..mu..sec pulse width and 180 pps. Over 200 of the klystrons are in routine operation in SLC. An experimental klystron at 8.568 GHz is presently under construction with a design objective of 30 MW at 1 ..mu..sec. A program is starting on the relativistic klystron whose performance will be analyzed in the exploration of the limits of klystrons at very short pulse widths.
Performance of the SLAC Linear Collider klystrons: There are now 200 new, high power 5045 klystrons installed on the two-mile Stanford Linear Accelerator. Peak power per klystron averages over 63 MW. Average energy contribution is above 240 MeV per station. Electron beam energy has been measured as high as 53 GeV. Energy instability due to klystron malfunction is less than 0.2%. The installed klystrons have logged over one million operating hours with close to 20,000 klystron hours cumulative operating time between failures. Data are being accumulated on klystron operation and failure modes with failure signatures starting to become apparent. To date, no wholesale failure modes have surfaced that would impair the SLAC Linear Collider (SLC) program.
Assessment of foreign decommissioning technology with potential application to US decommissioning needs: This study was conducted by the Pacific Northwest Laboratory (PNL) for the US Department of Energy (DOE) to identify and technically assess foreign decommissioning technology developments that may represent significant improvements over decommissioning technology currently available or under development in the United States. Technology need areas for nuclear power reactor decommissioning operations were identified and prioritized using the results of past light water reactor (LWR) decommissioning studies to quantitatively evaluate the potential for reducing cost and decommissioning worker radiation dose for each major decommissioning activity. Based on these identified needs, current foreign decommissioning technologies of potential interest to the US were identified through personal contacts and the collection and review of an extensive body of decommissioning literature. These technologies were then assessed qualitatively to evaluate their uniqueness, potential for a significant reduction in decommissioning costs and/or worker radiation dose, development status, and other factors affecting their value and applicability to US needs.

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