Enhanced durability and reactivity for zinc ferrite desulfurization sorbent (open access)

Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.
Date: November 14, 1988
Creator: Jha, Mahesh C. & Berggren, Mark H.
Object Type: Report
System: The UNT Digital Library
A microwave power driver for linac colliders: Gigatron (open access)

A microwave power driver for linac colliders: Gigatron

The gigatron is a new rf amplifier tube designed for linac collider applications. Three design features permit extension of the lasertron concept to very high frequencies. First, a gated field-emitter array is employed for the modulated cathode. Second, a ribbon beam geometry mitigates space charge depression and facilitates efficient output coupling. Third, a traveling wave output coupler is used to obtain optimum coupling to the ribbon beam. This paper describes recent developments in the gigatron design, and progress towards experimental tests. 9 refs., 8 figs., 1 tab.
Date: November 18, 1988
Creator: Bizek, H.M.; Elliott, S.M.; McIntyre, P.M.; Nassiri, A.; Popovic, M.B.; Raparia, D. et al.
Object Type: Article
System: The UNT Digital Library
A Preliminary Report on X-Ray Photoabsorption Coefficients andAtomic Scattering Factors for 92 Elements in the 10-10,000 eVRegion (open access)

A Preliminary Report on X-Ray Photoabsorption Coefficients andAtomic Scattering Factors for 92 Elements in the 10-10,000 eVRegion

Based on currently available photoabsorption measurements and recent theoretical calculations by Doolen and Liberman (Physica Scripta 36, 77 (1987)), a revised (from ADNDT 27, 1 (1982)) best-fit determination of the photoabsorption cross sections is presented here for the elements Z=1 to Z=92 in the 10-10,000 eV range. The photoabsorption data used include those described in the Lockheed and DOE listings of research abstracts for the past ten years and those which have been recently added to the comprehensive NBS Measured Data Base (NBSIR 86-3461, Hubbell et al.). The best-fit curves are compared with both the compilation of measurements and the calculations by Doolen and Liberman. Using the photoabsorption curves, the atomic scattering factors have been calculated for the energy range 50-10,000 eV and are also presented in this report.
Date: November 1, 1988
Creator: Henke, B. L.; Davis, J. C.; Gullikson, E. M. & Perera, R. C. C.
Object Type: Report
System: The UNT Digital Library
(Diffraction gratings used in x-ray spectroscopy): Final report (open access)

(Diffraction gratings used in x-ray spectroscopy): Final report

This subcontract was initiated in order to facilitate the development at MIT of technologies for fabricating the very fine diffraction grating required in x-ray spectroscopy at Lawrence Livermore Laboratory (LLL). These gratings are generally gold transmission gratings with spatial periods of 200 nm or less. The major focus of our efforts was to develop a means of fabricating gratings of 100 nm period. We explored two approaches: e-beam fabrication of x-ray lithography masks, and achromatic holographic lithography. This work was pursued by Erik Anderson as a major component of his Ph.D. thesis. Erik was successful in both the e-beam and holographic approaches. However, the e-beam method proved to be highly impractical: exposure times of about 115 days would be required to cover an area of 1 cm/sup 2/. The achromatic holography, on the other hand, should be capable of exposing areas well in excess of 1 cm/sup 2/ in times under 1 hour. Moreover, 100 nm-period gratings produced by achromatic holography are coherent over their entire area whereas gratings produced by e-beam lithography are coherent only over areas /approximately/100 ..mu..m. The remainder of this report consists of portions excerpted from Erik Anderson's thesis. These contain all the details of our …
Date: November 1, 1988
Creator: Smith, H.I.
Object Type: Report
System: The UNT Digital Library
Non-equilibrium dynamics in finite-temperature QCD (open access)

Non-equilibrium dynamics in finite-temperature QCD

An overview on the status of kinetic theory approaches to non-equilibrium dynamics in finite temperature QCD is given, and results and difficulties in determining the transport properties and equilibration time scales for a quark gluon plasma produced in nuclear collisions are discussed. 15 refs.
Date: November 1, 1988
Creator: Heinz, U.
Object Type: Article
System: The UNT Digital Library
History of the application of the generalized Lewis acid-base theory to metals (open access)

History of the application of the generalized Lewis acid-base theory to metals

The history of my experiences with intermetallics has been found useful by students seeking my advice on which directions in science they should be emphasizing. In response to their question, I point to a mobile in my office consisting of seven hands pointing in different directions. Science comes up with so many unexpected developments that one's education should have a broad enough base to allow one to branch out in any direction to take advantage of unexpected opportunities. My historical presentation will be a personal account that I hope will serve as a guide to students. There have been many unexpected abrupt changes in my research.
Date: November 1, 1988
Creator: Brewer, L.
Object Type: Article
System: The UNT Digital Library
Effect of lepton energy resolution on Higgs searches at the SSC (open access)

Effect of lepton energy resolution on Higgs searches at the SSC

We discuss the effects of realistic detector resolutions on the processes H ..-->.. ZZ ..-->.. e/sup +/e/sup /minus//e/sup +/e/sup /minus// and H ..-->.. ZZ ..-->.. e/sup +/e/sup minus/..mu../sup +/..mu../sup /minus// at the SSC. The background from Zt/bar t/ where the t/bar t/ system produces two isolated leptons in its decays is discussed. 10 refs., 6 figs., 2 tabs.
Date: November 1, 1988
Creator: Hinchliffe, I. & Wang, E.M.
Object Type: Article
System: The UNT Digital Library
Mechanisms governing fine particulate emissions from coal flames (open access)

Mechanisms governing fine particulate emissions from coal flames

The overall objectives of this project are to provide a basic understanding of the principal processes that govern fine particulate formation in pulverized coal flames, and develop procedures to predict the levels of emission of fine particles from pulverized coal combustors. (VC)
Date: November 1, 1988
Creator: Clark, W. D.; Chen, S. L.; Kramlich, J. C.; Newton, G. H.; Seeker, W. R. (Energy and Environmental Research Corp., Irvine, CA (United States)) & Samuelsen, G. S. (California Univ., Irvine, CA (United States))
Object Type: Report
System: The UNT Digital Library
Proceedings of the second users meeting for the Advanced Photon Source (open access)

Proceedings of the second users meeting for the Advanced Photon Source

The second national users meeting for the Advanced Photon Source (APS) at Argonne National Laboratory -- held March 9--10, 1988, at Argonne -- brought scientists and engineers from industry, universities, and national laboratories together to review the status of the facility and expectations for its use. Presented papers and status reports in these proceedings include the current status of the APS with respect to accelerator systems, experimental facilities, and conventional facilities; scientific papers on frontiers in synchrotron applications summaries of reports on workshops held by users in certain topical groups; reports in research and development activities in support of the APS at other synchrotron facilities; and noted from a discussion of APS user access policy. In addition, actions taken by the APS Users Organization and its Executive Committee are documented in this report.
Date: November 1, 1988
Creator: unknown
Object Type: Article
System: The UNT Digital Library
Some continuously variable partial snakes of Type 1 and Type 2 (open access)

Some continuously variable partial snakes of Type 1 and Type 2

In order to obtain polarized beam in proton accelerators, Siberian snakes of two types may be needed in order to establish a spin tune independent of energy. We have done a numerical study to find a type II partial snake and to find more exact solutions for the type I partial snakes previously proposed. We find a type II partial snake. We find that the unequal field integrals needed to modify approximate type I snakes to exactly type I snakes with horizontal and vertical bends result in unacceptably large orbit excursions. We find a new type I snake with smaller field integrals at small overall rotation. An 8 magnet type II snake works from 0 to {pi} but more magnets might be used to reduce the excursion at small angle. Also, no type I partial snake with as few as 8 magnets has been found which will work continuously from 0 to {pi}. It appears that horizontal and vertical bends cannot provide solutions for pure type I or type II that allow the field integrals to approach zero as the rotation goes to zero. Versions of both the new type I and type II partial snakes are presently used as …
Date: November 30, 1988
Creator: Underwood, D.G.
Object Type: Report
System: The UNT Digital Library
Proceedings of the Chinese-American symposium on energy markets and the future of energy demand (open access)

Proceedings of the Chinese-American symposium on energy markets and the future of energy demand

The Symposium was organized by the Energy Research Institute of the State Economic Commission of China, and the Lawrence Berkeley Laboratory and Johns Hopkins University from the United States. It was held at the Johns Hopkins University Nanjing Center in late June 1988. It was attended by about 15 Chinese and an equal number of US experts on various topics related to energy demand and supply. Each presenter is one of the best observers of the energy situation in their field. A Chinese and US speaker presented papers on each topic. In all, about 30 papers were presented over a period of two and one half days. Each paper was translated into English and Chinese. The Chinese papers provide an excellent overview of the emerging energy demand and supply situation in China and the obstacles the Chinese planners face in managing the expected increase in demand for energy. These are matched by papers that discuss the energy situation in the US and worldwide, and the implications of the changes in the world energy situation on both countries. The papers in Part 1 provide historical background and discuss future directions. The papers in Part 2 focus on the historical development of …
Date: November 1, 1988
Creator: Meyers, S. (ed.)
Object Type: Article
System: The UNT Digital Library
Some TPC (Time Projection Chamber) measurements in an oxygen beam at the AGS (open access)

Some TPC (Time Projection Chamber) measurements in an oxygen beam at the AGS

The principal detector for AGS Experiment 810 is a Time Projection Chamber (TPC) in which it is intended to measure momenta and angles of a major fraction of the charged particles from each light ion collision. This report describes the results of a test of a prototype of the TPC in a beam of (14.6 /times/ 16 = 233.6 GeV/c) oxygen ions run in June of this year.
Date: November 15, 1988
Creator: Love, W. A.; Bonner, B. E.; Buchanan, J. A.; Chan, C. S.; Chiou, C. N.; Clement, J. M. et al.
Object Type: Article
System: The UNT Digital Library
On the survivability of diagnostic windows in the CIT (Compact Ignition Tokamak) reactor (open access)

On the survivability of diagnostic windows in the CIT (Compact Ignition Tokamak) reactor

The problem of radiation induced stresses in CIT diagnostic windows is discussed. Existing data indicate windows of existing design will probably survive if placed on the periphery of the reactor. There is a lack of adequate engineering data upon which the design and survivability of windows can be based. 22 refs., 5 figs., 2 tabs.
Date: November 1, 1988
Creator: Taylor, A.
Object Type: Article
System: The UNT Digital Library
Proceedings of the DOE/Industry Sensor Working Group meeting, Austin, Texas (open access)

Proceedings of the DOE/Industry Sensor Working Group meeting, Austin, Texas

This paper report contains topics presented at a sensor workshop group meeting. The topics describe measuring instruments of use in the pulp and paper industry. Topics include: measurement of solids fraction; process instrumentation research for the pulp paper industry; real-time non-contact optical surface motion monitor; on-machine sensors to measure paper mechanical properties; hierarchical intelligent control of industrial processes -- an in-parallel lime kiln application; proposal for research on lignin concentration measurement in pulping liquors; and advanced polymeric sensor materials for industrial drying.
Date: November 1, 1988
Creator: unknown
Object Type: Article
System: The UNT Digital Library
Stability diagrams for fourfold coordination of polyvalent metal ions in molten mixtures of halide salts (open access)

Stability diagrams for fourfold coordination of polyvalent metal ions in molten mixtures of halide salts

The stability of local fourfold coordination for divalent and trivalent metal ions in liquid mixtures of polyvalent metal halides and alkali halides is classified by means of structural coordinates obtained from properties of the elements. In parallel with earlier classifications of compound crystal structures and molecular shapes, the elemental properties are taken from first-principles calculations of valence electron orbitals in atoms, in the form of (i) the nodal radii of Andreoni, Baldereschi and Guizzetti or (ii) the pseudopotential radii or Zunger and Cohen. As a third alternative a classification based on Pettifor's phenomenological chemical scale of the elements is also considered. The alternative structural classification schemes that are developed from these elemental properties are generally successfully in distinguishing molten mixtures in which the available experimental evidence indicates long-lived fourfold coordination of polyvalent metal ions. In addition, Pettifor's chemical scale scheme is useful in sorting out finer details of local coordination in the liquid state. 3 figs., 71 refs.
Date: November 1, 1988
Creator: Akdeniz, Z. (International Centre for Theoretical Physics, Trieste (Italy) Istanbul Univ. (Turkey). Dept. of Physics) & Tosi, M.P. (Trieste Univ. (Italy). Dipt. di Fisica Teorica Argonne National Lab., IL (USA))
Object Type: Report
System: The UNT Digital Library
Hadronic energy spectra from nuclear collisions: Effects from collective transverse flow and the phase transition to quark matter (open access)

Hadronic energy spectra from nuclear collisions: Effects from collective transverse flow and the phase transition to quark matter

I give an overview of the processes determining the shape of energy spectra of hadrons emitted in relativistic nuclear collisions, and discuss how one can extract from them information on the presence of collective transverse flow and on the transition to quark-gluon matter in such collisions. 6 refs., 3 figs.
Date: November 1, 1988
Creator: Heinz, U.
Object Type: Article
System: The UNT Digital Library
Lessons learned at West Valley during facility decontamination for re-use (1982--1988) (open access)

Lessons learned at West Valley during facility decontamination for re-use (1982--1988)

The primary mission of the West Valley Demonstration Project (WVDP) is to solidify a large volume of high-level liquid waste (2.3 million liters -- 600,000 gallons) produced during reprocessing plant operations and stored in underground tanks. This is to be accomplished through the maximum use of existing facilities. This required a significant effort to remove existing equipment and to decontaminate areas for installation of liquid and cement processing systems in a safe environment while maintaining exposure to workers as low as reasonably achievable. The reprocessing plant occupied a building of about 33,000 m/sup 2/ (350,000 ft/sup 2/). When the WVDP was initiated, approximately 6 percent of the plant area was in a non-contaminated condition where personnel could function without protective clothing or radiological controls. From 1982 to 1988, an additional 64 percent of the plant was cleaned up and much of this converted to low- and high-level waste processing areas. The high-level liquid and resulting low-level liquids are now being treated in these areas using an Integrated Radwaste Treatment System (IRTS). The Project has now focused attention on installation, qualification and operation of a vitrification system which will convert the remaining high-level waste into borosilicate glass logs. The stabilized waste …
Date: November 1, 1988
Creator: Tundo, D.; Gessner, R.F. & Lawrence, R.E.
Object Type: Report
System: The UNT Digital Library
Impurity transport in ohmically heated TFTR plasmas (open access)

Impurity transport in ohmically heated TFTR plasmas

Impurity transport in ohmically heated TFTR plasmas is studied by computer modeling of VUV line emissions from impurities injected using the laser-blowoff technique. The results are sensitive to uncertainties in the ionization and recombination rates used in the modeling; as a result, only a spatially averaged diffusion coefficient and parameterized convective velocity can be measured. Measurements of these transport parameters are presented for deuterium and helium discharges with I/sub p/ = 0.8-2.5 MA, /bar n/sub e// = 0.6-6.0/times/10/sup 19/ m/sup -3/, and Z/sub eff/ = 2-6. Diffusion coefficients are found to be in the 0.5-1.5 m/sup 2//s range, considerably larger than neoclassical values. Nonzero inward convective velocities are necessary to fit the data in most cases. No dependence of the diffusion coefficient on injected element, working gas species, or plasma current is found, but at a given current, the diffusion coefficient is smaller by approximately a factor of two in plasmas near the density limit than in discharges with /bar n/sub e//<3/times/10/sup 19/ m/sup -3/. 31 refs., 9 figs., 3 tabs.
Date: November 1, 1988
Creator: Stratton, B. C.; Fonck, R. J.; Hulse, R. A.; Ramsey, A. T.; Timberlake, J.; Efthimion, P. C. et al.
Object Type: Report
System: The UNT Digital Library
Using the transportable, computer-operated, liquid-scintillator fast-neutron spectrometer system (open access)

Using the transportable, computer-operated, liquid-scintillator fast-neutron spectrometer system

When a detailed energy spectrum is needed for radiation-protection measurements from approximately 1 MeV up to several tens of MeV, organic-liquid scintillators make good neutron spectrometers. However, such a spectrometer requires a sophisticated electronics system and a computer to reduce the spectrum from the recorded data. Recently, we added a Nuclear Instrument Module (NIM) multichannel analyzer and a lap-top computer to the NIM electronics we have used for several years. The result is a transportable fast-neutron spectrometer system. The computer was programmed to guide the user through setting up the system, calibrating the spectrometer, measuring the spectrum, and reducing the data. Measurements can be made over three energy ranges, 0.6--2 MeV, 1.1--8 MeV, or 1.6--16 MeV, with the spectrum presented in 0.1-MeV increments. Results can be stored on a disk, presented in a table, and shown in graphical form. 5 refs., 51 figs.
Date: November 1, 1988
Creator: Thorngate, J.H.
Object Type: Report
System: The UNT Digital Library
HISTRAP: Proposal for a Heavy Ion Storage Ring for Atomic Physics (open access)

HISTRAP: Proposal for a Heavy Ion Storage Ring for Atomic Physics

This paper presents an overview of the physics capabilities of HISTRAP together with a brief description of the facility and a sampling of the beams which will be available for experimentation, and surveys some of the lines of investigation in the physics of multicharged ions, molecular ion spectroscopy, condensed beams, and nuclear physics that will become possible with the advent of HISTRAP. Details of the accelerator design are discussed, including computer studies of beam tracking in the HISTRAP lattice, a discussion of the HHIRF tandem and ECR/RFQ injectors, and a description of the electron beam cooling system. In the past three years, HISTRAP has received substantial support from Oak Ridge National Laboratory management and staff. The project has used discretionary funds to develop hardware prototypes and carry out design studies. Construction has been completed on a vacuum test stand which models 1/16 of the storage ring and has attained a pressure of 4 x 10/sup -12/ Torr; a prototype rf cavity capable of accelerating beams up to 90 MeV/nucleon and decelerating to 20 keV/nucleon; and a prototype dipole magnet, one of the eight required for the HISTRAP lattice. This paper also contains a summary of the work on electron cooling …
Date: November 1, 1988
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Gyrokinetic energy conservation and Poisson-bracket formulation (open access)

Gyrokinetic energy conservation and Poisson-bracket formulation

An integral expression for the gyrokinetic total energy of a magnetized plasma with general magnetic field configuration perturbed by fully electromagnetic fields was recently derived through the use of a gyro-center Lie transformation. We show that the gyrokinetic energy is conserved by the gyrokinetic Hamiltonian flow to all orders in perturbed fields. This paper is concerned with the explicit demonstration that a gyrokinetic Hamiltonian containing quadratic nonlinearities preserves the gyrokinetic energy up to third order. The Poisson-bracket formulation greatly facilitates this demonstration with the help of the Jacobi identity and other properties of the Poisson brackets. 18 refs.
Date: November 1, 1988
Creator: Brizard, A.
Object Type: Report
System: The UNT Digital Library
Computer simulation of mixed classical-quantum systems (open access)

Computer simulation of mixed classical-quantum systems

We briefly review three important methods that are currently used in the simulation of mixed systems. Two of these techniques, path integral Monte Carlo or molecular dynamics and dynamical simulated annealing, have the limitation that they can only describe the structural properties in the ground state. The third so-called quantum molecular dynamics (QMD) method can provide not only the static properties but also the real-time dynamics of a quantum particle at finite temperatures. 10 refs.
Date: November 1, 1988
Creator: Kalia, R.K. & Vashishta, P.
Object Type: Article
System: The UNT Digital Library
Review of J//psi/ decays (open access)

Review of J//psi/ decays

Recent results from the Mark III collaboration in radiative J//psi/ decays are presented. This includes a study of iota/E decays in J//psi/ el/eta/ and elelp, two pseudoscalar decays near threshold in J//psi/ el and el /bar K/K and two vector decays in J//psi/ el /bar K//sup o/*K/sup o/*. 20 refs., 9 figs.
Date: November 1, 1988
Creator: Toki, W.H.
Object Type: Article
System: The UNT Digital Library
Final focus supports for a TeV Linear Collider (open access)

Final focus supports for a TeV Linear Collider

Final focus quadrupoles supported from structures in the endcap region of a physics experiment appear to meet the high-frequency vibration and stability criteria for a TeV Linear Collider (TLC). The support stays within a ten-degree cone, minimizing interference with the experimental apparatus. 3 refs., 3 figs.
Date: November 1, 1988
Creator: Ash, W.W.
Object Type: Article
System: The UNT Digital Library