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Three Dimensional Laser Cooling of Stored and Circulating Ion Beams by Means of a Coupling Cavity

Description: It is shown, theoretically, that a coupling cavity; namely an rf cavity operating in the TM{sup 210} mode, when inserted in a storage ring will enhance the coupling between longitudinal and transverse degrees of freedom. As a result, it is shown that the demonstrated very effective laser cooling of the longitudinal motion, can now be extended to transverse motion; i.e., employed to cool a beam in all three directions.
Date: February 1, 1994
Creator: Okamoto, H.; Sessler, Andrew M. & Mohl, D.
Partner: UNT Libraries Government Documents Department
open access

Vision Denton '94

Description: Clippings from the Denton Record-Chronicle titled 'Vision Denton '94, City builds on education reputation'. The two clippings are part of the same story covering the collaboration of colleges including UNT, museums, and DFW Metroplex area schools. The collaboration offers better art programs and college credit to high schoolers.
Date: February 12, 1994
Creator: Cobler, Paula
Partner: UNT Libraries Special Collections
open access

Waste minimization at Lawrence Livermore National Laboratory: A case study of environmentally conscious manufacturing

Description: The purpose of this paper is to provide an update on what we`ve accomplished and have planned in our plating operation at Lawrence Livermore National Laboratory (LLNL) in the area of waste minimization. Our efforts have included issues other than waste minimization and, therefore, fall under the wider umbrella entitled pollution prevention or environmentally conscious electroplating. Approximately one year has passed since our last report on pollution prevention and since this topic remains a h… more
Date: February 1, 1994
Creator: Steffani, C. P. & Dini, J. W.
Partner: UNT Libraries Government Documents Department
open access

Near-extinction and final burnout in coal combustion

Description: The late stages of char combustion have a special technological significance, as carbon conversions of 99% or greater are typically required for the economic operation of pulverized coal fired boilers. In the present article, two independent optical techniques are used to investigate near-extinction and final burnout phenomenas. Captive particle image sequences, combined with in situ optical measurements on entrained particles, provide dramatic illustration of the asymptotic nature of the char … more
Date: February 1, 1994
Creator: Hurt, R. H. & Davis, K. A.
Partner: UNT Libraries Government Documents Department
open access

Automated fiber pigtailing technology

Description: The high cost of optoelectronic (OE) devices is due mainly to the labor-intensive packaging process. Manually pigtailing such devices as single-mode laser diodes and modulators is very time consuming with poor quality control. The Photonics Program and the Engineering Research Division at LLNL are addressing several issues associated with automatically packaging OE devices. A furry automated system must include high-precision fiber alignment, fiber attachment techniques, in-situ quality control… more
Date: February 1, 1994
Creator: Strand, O. T.; Lowry, M. E.; Lu, S. Y.; Nelson, D. C.; Nikkel, D. J.; Pocha, M. D. et al.
Partner: UNT Libraries Government Documents Department
open access

Ten new checks to assess the statistical quality of Monte Carlo solutions in MCNP

Description: The central limit theorem can be applied to a Monte Carlo solution if: The random variable x has a finite mean and a finite variance; and the number N of independent observations grows large. When these two conditions are satisfied, a confidence interval based on the normal distribution with a specified coverage probability can be formed. The first requirement is generally satisfied by the knowledge of the type of Monte Carlo tally being used. The Monte Carlo practitioner has only a limited num… more
Date: February 1, 1994
Creator: Forster, R. A.; Booth, T. E. & Pederson, S. P.
Partner: UNT Libraries Government Documents Department
open access

Distributions of 14 elements into 10 liquid extractants from simulated acid-dissolved sludge and acidified supernate solutions of Hanford high-level waste

Description: The distributions of 14 elements into ten extractants were measured from simulant solutions that represent acidic dissolved sludge and acidified supernate from Hanford HLW Tank 102-SY. The extractants: LIX{sup TM}-26, LIX{sup TM}-54, LIX{sup TM}-84, LIX{sup TM}-1010, Cyanex{sup TM} 272, Cyanex{sup TM} 923, Aliquat{sup TM} 336, DHDECMP, DHDECMP-DIPB, and CMPO-DIPB, were sorbed on porous carbon beads to provide dry-appearing beads that would be suitable for column operations. The selected element… more
Date: February 1, 1994
Creator: Marsh, S. F.; Svitra, Z. V. & Bowen, S. M.
Partner: UNT Libraries Government Documents Department
open access

Changes in Organic Sulfur Compounds in Coal Macerals During Liquefaction

Description: Several general trends were observed in reactivity patterns of sulfur compounds in macerals. Sulfur is reduced in the asphaltene fraction compared to initial maceral. Aliphatics are removed and polycyclic aromatic compounds are both stable and probably formed under these conditions. Molecules containing two sulfur atoms are formed. The preasphaltenes are now being analyzed by DEIHRMS.
Date: February 1, 1994
Creator: Winans, R. E.; Joseph, J. T. & Fisher, R. B.
Partner: UNT Libraries Government Documents Department
open access

Technology features of a network technology for safeguards applications

Description: This report describes a new flexible technology which is now available to design sensor and control networks based on a protocol embedded in an intelligent communications processor. The flexibility allows a system designer and/or a technical installer to make appropriate tradeoffs among simplicity, functionality, and cost in the design of network nodes and their installation. This is especially important in designing an installation scenario for the safeguards network. The network technology pe… more
Date: February 1, 1994
Creator: Johnson, C. S.
Partner: UNT Libraries Government Documents Department
open access

Unique passive diagnostic for slapper detonators

Description: The objective of this study was to find a material and configuration that could reliably detect the proper functioning of a current slapper detonator. Because of the small size of the slapper geometry (on the order of a 15 mils), most diagnostic techniques are not suitable. This program has the additional requirement that the device could not use any electrical power or output signals. This required that the diagnostic be completely passive. The paper describes the three facets of the developme… more
Date: February 1, 1994
Creator: Brigham, W. P. & Schwartz, J. J.
Partner: UNT Libraries Government Documents Department
open access

The TORSED and TORSET codes for coupling three-dimensional TORT calculations

Description: Two new codes perform ``bootstrapping`` of either two- or three-dimensional boundary fluxes to a TORT three-dimensional calculation. TORSED couples a DORT RZ calculation to an XYZ TORT. Two methods of directional remapping are available, each less expensive than methods previously available for this work. TORSED is compatible with the discontinuous mesh features of TORT. The second code, TORSET, couples two XYZ TORT problems. The second problem may lie entirely inside the first, or it may touch… more
Date: February 1, 1994
Creator: Rhoades, W. A.
Partner: UNT Libraries Government Documents Department
open access

Approach for systematic evaluation of transuranic waste management alternatives

Description: This paper describes an approach for systematic evaluation of management alternatives that are being considered for the treatment, storage, and disposal of transuranic waste (TRUW) at U.S. Department of Energy sites. The approach, which is currently under development, would apply WASTE-MGMT, a database application model developed at Argonne National Laboratory, to estimate projected environmental releases and would evaluate impact measures such as health risk and costs associated with each of t… more
Date: February 1, 1994
Creator: Hong, K.; Koebnick, B. & Kotek, T.
Partner: UNT Libraries Government Documents Department
open access

A brief introduction to symplectic integrators and recent results

Description: The author begins with a brief synopsis about Hamiltonian systems and symplectic maps. A symplectic integrator is a symplectic map {phi}(q,p;t) that systematically approximates the time t flow of a Hamiltonian system. Systematic means: (1) in time step, t, i.e. the error should vanish as some power of the time step, and (2) in order of approximation, i.e. one would like a hierarchy of such {phi} that have errors that vanish as successively higher powers of the time step. At present the authors … more
Date: February 1, 1994
Creator: Channell, P. J.
Partner: UNT Libraries Government Documents Department
open access

Prospects for studies of ground-state proton decays with the Holifield Radioactive Ion Beam Facility

Description: By using radioactive ions from the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory it should be possible to identify many new ground-state proton emitters in the mass region from Sn to Pb. During this production and search process the limits of stability on the proton-rich side of the nuclidic chart will be delineated for a significant fraction of medium-weight elements and our understanding of the proton-emission process will be expanded and improved.
Date: February 1, 1994
Creator: Toth, K. S.
Partner: UNT Libraries Government Documents Department
open access

Criticality safety aspects of decontamination and decommissioning at defense nuclear facilities

Description: Defense nuclear facilities have operated for forty years with a well-defined mission to produce weapons components for the nation. With the end of the cold war, the facilities` missions have changed to one of decontamination and decommissioning. Off-normal operations and use of new procedures, such as will exist during these activities, have often been among the causal factors in previous criticality accidents at process facilities. This paper explores the similarities in causal factors in prev… more
Date: February 1, 1994
Creator: Croucher, D. W.
Partner: UNT Libraries Government Documents Department
open access

Dual-band infrared imaging for concrete bridge deck inspection

Description: Dual-band infrared (DBIR) imaging methods and unique image-correction algorithms used successfully for underground and obscured object imaging and detection (of buried mines, archaeological structures, geothermal aquifers and airframe defects) are adapted for inspection of concrete highways and bridge decks to provide early warnings of subsurface defects. To this end, we prepared small concrete test slabs with defects (embedded plastic layers). We used selective DBIR (3--5 {mu}m and 8--12 {mu}m… more
Date: February 1, 1994
Creator: Durbin, P. & Del Grande, N.
Partner: UNT Libraries Government Documents Department
open access

The Rocky Flats Plant Waste Stream and Residue Identification and Characterization Program (WSRIC): Progress and achievements

Description: The Waste Stream and Residue Identification and Characterization (WSRIC) Program, as described in the WSRIC Program Description delineates the process knowledge used to identify and characterize currently-generated waste from approximately 5404 waste streams originating from 576 processes in 288 buildings at Rocky Flats Plant (RFP). Annual updates to the WSRIC documents are required by the Federal Facilities Compliance Agreement between the US Department of Energy, the Colorado Department of He… more
Date: February 1, 1994
Creator: Ideker, V. L. & Doyle, G. M.
Partner: UNT Libraries Government Documents Department
open access

Semiconductor microcavity lasers

Description: New kinds of semiconductor microcavity lasers are being created by modern semiconductor technologies like molecular beam epitaxy and electron beam lithography. These new microcavities exploit 3-dimensional architectures possible with epitaxial layering and surface patterning. The physical properties of these microcavities are intimately related to the geometry imposed on the semiconductor materials. Among these microcavities are surface-emitting structures which have many useful properties for … more
Date: February 1, 1994
Creator: Gourley, P. L.; Wendt, J. R.; Vawter, G. A.; Warren, M. E.; Brennan, T. M. & Hammons, B. E.
Partner: UNT Libraries Government Documents Department
open access

Coupling correction using closed orbit measurements

Description: The authors describe a coupling correction scheme they have developed and used to successfully reduce the vertical emittance of the NSLS X-Ray ring by a factor of 6 to below 2 A. This gives a vertical to horizontal emittance ratio of less than 0.2%. They find the strengths of 17 skew quadrupoles to simultaneously minimize the vertical dispersion and the coupling. As a measure of coupling they utilize the shift in vertical closed orbit resulting from a change in strength of a horizontal steering… more
Date: February 18, 1994
Creator: Safranek, J. & Krinsky, S.
Partner: UNT Libraries Government Documents Department
open access

Parallel processing Monte Carlo radiation transport codes

Description: Issues related to distributed-memory multiprocessing as applied to Monte Carlo radiation transport are discussed. Measurements of communication overhead are presented for the radiation transport code MCNP which employs the communication software package PVM, and average efficiency curves are provided for a homogeneous virtual machine.
Date: February 1, 1994
Creator: McKinney, G. W.
Partner: UNT Libraries Government Documents Department
open access

Advances in and uses of gamma-ray field instrumentation at Los Alamos

Description: We are developing a set of tools to be used by the Safeguards Assay Group to solve problems found in safeguards and the domestic nuclear industry. The tools are also applicable to problems dealing with the environment, defense, and other areas of national and international interest. We have used extensively the advances in hardware and software since our last multichannel analyzer (MCA) development activities over a decade ago. We are also using our experience with and feedback from users of ou… more
Date: February 1, 1994
Creator: Halbig, J. K.; Klosterbuer, S. F.; Russo, P. A.; Sprinkle, J. K. Jr.; Smith, S. E. & Ianakiev, K.
Partner: UNT Libraries Government Documents Department
open access

Managing performance of DB2 Ad Hoc Reports

Description: The DB2 financial reporting systems at Westinghouse Savannah River Company consists of 212 standardized reports that over 1034 users have accessed in 1993 to generate their reports. Each report has a range of selection criteria that the users can specify. Depending on the selection criteria, a report can access from a few rows to millions of rows of data. When this new DB2 system went into production in 1992, the CPU was at 100% utilization. From the beginning, ad hoc reports had a backlog of 4… more
Date: February 1, 1994
Creator: Chow, A.
Partner: UNT Libraries Government Documents Department
open access

In situ studies of zeolite syntheses using powder diffraction methods: Crystallization of ``instant zeolite A`` powder and CoAPO-5

Description: A series of hydrothermal zeolite synthesis were performed on a powder diffractometer using synchrotron radiation and a position sensitive detector. Direct observation of the induction period (nucleation stage), crystallization and transformation of zeolite 4A (Na-LTA) was possible due to the intense X-ray beam which allows fast data collection. High pressure experiments were performed, allowing observation of hydrothermal synthesis of a cobalt substituted AlPO{sub 4}-zeolite, CoAPO-5, up to 165… more
Date: February 1, 1994
Creator: Norby, P.; Christensen, A. N. & Hanson, J. C.
Partner: UNT Libraries Government Documents Department
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