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[Aspects of photoionization of impurities and electron transfer in ionic crystals]. Final report, [September 1984--September 1991]

Description: Spectral evidence was found for photoionization in spectra of Eu{sup 2+} and Sm{sup 3+} in BaF{sub 2}; Ce{sup 3+} was also studied in BaF{sub 2}, CaF{sub 2}, and SrF{sub 2}. Two-photon spectroscopy of forbidden transitions (zero-phonon lines) was extended from NaF: Cu{sup +} to Mn{sup 4+} in Cs{sub 2}GeF{sub 6} and to MgO:Ni{sup 2+}.
Date: February 10, 1993
Creator: McClure, D. S.

Assessment of nuclear safety and nuclear criticality potential in the Defense Waste Processing Facility

Description: A panel of experts in the fields of process engineering, process chemistry, and safety analysis met together on January 26, 1993, and February 19, 1993, to discuss nuclear safety and nuclear criticality potential in the Defense Waste Processing Facility (DWPF) processes. Nuclear safety issues and possibilities of nuclear criticality incidents in the DWPF were examined in depth. The discussion started at the receipt of slurry feeds: The Low Point Pump Pit Precipitate Tank (LPPPPT) and the Low Point Pump Pit Sludge Tank (LPPPST), and went into detail the whole DWPF processes. This report provides discussion of each of the areas and processes of the DWPF in terms of potential nuclear safety issues and nuclear criticality concerns.
Date: May 10, 1993
Creator: Ha, B. C.

Assessment of the safety of US nuclear weapons and related nuclear test requirements: A post-Bush Initiative update

Description: The Nuclear Weapons Reduction Initiative announced by President Bush on September 27, 1991, is described herein as set forth in Defense Secretary Cheney`s Nuclear Arsenal Reduction Order issued September 28, 1991. The implications of the Bush Initiative for improved nuclear weapons safety are assessed in response to a request by US Senators Harkin, Kennedy, and Wirth to the Lawrence Livermore National Laboratory that the author prepare such an assessment. The author provides an estimate of the number of nuclear tests needed to accomplish a variety of specified warhead safety upgrades, then uses the results of this estimate to answer three questions posed by the Senators. These questions concern pit reuse and the number of nuclear tests needed for specified safety upgrades of those ballistic missiles not scheduled for retirement, namely the Minuteman III, C4, and D5 missiles.
Date: December 10, 1991
Creator: Kidder, R. E.

Assurance in Agent-Based Systems

Description: Our vision of the future of information systems is one that includes engineered collectives of software agents which are situated in an environment over years and which increasingly improve the performance of the overall system of which they are a part. At a minimum, the movement of agent and multi-agent technology into National Security applications, including their use in information assurance, is apparent today. The use of deliberative, autonomous agents in high-consequence/high-security applications will require a commensurate level of protection and confidence in the predictability of system-level behavior. At Sandia National Laboratories, we have defined and are addressing a research agenda that integrates the surety (safety, security, and reliability) into agent-based systems at a deep level. Surety is addressed at multiple levels: The integrity of individual agents must be protected by addressing potential failure modes and vulnerabilities to malevolent threats. Providing for the surety of the collective requires attention to communications surety issues and mechanisms for identifying and working with trusted collaborators. At the highest level, using agent-based collectives within a large-scale distributed system requires the development of principled design methods to deliver the desired emergent performance or surety characteristics. This position paper will outline the research directions underway at Sandia, will discuss relevant work being performed elsewhere, and will report progress to date toward assurance in agent-based systems.
Date: May 10, 1999
Creator: Gilliom, Laura R. & Goldsmith, Steven Y.

ATLAS 10 GHz ECR ions source upgrade project.

Description: A major upgrade of the first ATLAS 10 GHz ECR ion source, which began operations in 1987, is in the planning and procurement phase. The new design will convert the old two-stage source into a single-stage source with an electron donor disk and high gradient magnetic field that preserves radial access for solid material feeds and pumping of the plasma chamber. The new magnetic field profile allows for the possibility of a second ECR zone at a frequency of 14 GHz. An open hexapole configuration, using a high energy-product Nd-Fe-B magnet material, having an inner diameter of 8.8 cm and pole gaps of 2.4 cm has been adopted. Models indicate that the field strengths at the chamber wall, 4 cm in radius, will be 9.3 kG along the magnet poles and 5.6 kG along the pole gaps. The individual magnet bars will be housed in austenitic stainless steel allowing the magnet housing within the aluminum plasma chamber to be used as a water channel for direct cooling of the magnets. Eight solenoid coils from the existing ECR will be enclosed in an iron yoke to produce the axial mirror. Based on a current of 500 A, the final model predicts a minimum B field of 3 kG with injection and extraction mirror ratios of 4.4 and 2.9 respectively.
Date: August 10, 1999
Creator: Moehs, D. P.; Pardo, R. C.; Vondrasek, R. & Xie, D.

Atmospheric sciences transfer between research advances and energy-policy assessments (ASTRAEA). Final report, 1 April 1996--31 December 1997

Description: Consistent with the prime goal of the ASTRAEA project, as given in its peer-reviewed proposal, this final report is an informal report to DOE managers about a perceived DOE management problem, specifically, lack of vision in DOE`s Atmospheric Chemistry Program (ACP). After presenting a review of relevant, current literature, the author suggests a framework for conceiving new visions for ACP, namely, multidisciplinary research for energy policy, tackling tough (e.g., nonlinear) problems as a team, ahead of political curves. Two example visions for ACP are then described, called herein the CITIES Project (the Comprehensive Inventory of Trace Inhalants from Energy Sources Project) and the OCEAN Project (the Ocean-Circulation Energy-Aerosol Nonlinearities Project). Finally, the author suggests methods for DOE to provide ACP with needed vision.
Date: December 10, 1997
Creator: Slinn, W.G.N.

Atom transfer and rearrangement reactions catalyzed by methyltrioxorhenium, MTO

Description: Methyltrioxorhenium (MTO) catalyzes the desulfurization of thiiranes by triphenylphosphine. Enormous enhancement in rate is observed when the catalyst is pretreated with hydrogen sulfide prior to the reaction. Using 2-mercaptomethylthiophenol as a ligand, the author synthesized several model complexes to study the mechanism of this reaction. With suitable model systems, they were able to show that the active catalyst is a Re(V) species. The reactions are highly stereospecific and very tolerant to functional groups. As part of the studies, he synthesized and crystallographically characterized the first examples of neutral terminal and bridging Re(V)sulfidocomplexes. Some of these complexes undergo fast oxygen atom transfer reactions with organic and inorganic oxidants. Studies on these model complexes led them to the discovery that MTO catalyzes the selective oxidation of thiols to disulfides. This report contains the Introduction; ``Chapter 6: Isomerization of Propargylic Alcohols to Enones and Enals Catalyzed by Methylrhenium Trioxide``; and Conclusions.
Date: May 10, 1999
Creator: Jacob, J.

Atomic structures and compositions of internal interfaces. [Produced by internal oxidation of alloys]

Description: This research program addresses fundamental questions concerning the relations between atomic structures and compositions of homophase and heterophase interfaces. Metal/ceramic heterophase interfaces are created via the process of internal oxidation of metallic alloys. The interfaces are studied via a combination of conventional transmission electron microscopy, high resolution electron microscopy, field-ion microscopy and atom probe microscopy. The latter technique is employed to chemically sequence the interfacial region, and to show that the terminating (222) plane of MgO and CdO consists solely of oxygen atoms forthe Cu/MgO (111) and Ag/CdO (111) heterophase interfaces, respectively; this is achieved with no deconvolution of the experimental data. The evolution of metal/ceramic heterophase interfaces is studied by following the process of internal oxidation on an atomic scale from its very earliest stages. It is demonstrated that during the early stages of internal oxidation that metal atom clusters as well as hypo and hyperstoichiometric metal-oxygen clusters are present. Solute-atom segregation to grain boundaries is studied in binary metal alloys employing the free energy simulations and the overlapping distribution Monte Carlo methodologies for dilute Pt(Au), Cu(Ni) and Pd(Ni) alloys for both twist and tilt boundaries.
Date: May 10, 1993
Creator: Seidman, D.N. (Northwestern Univ., Evanston, IL (United States). Dept. of Materials Science and Engineering) & Merkle, K.L. (Argonne National Lab., IL (United States). Materials Science Div.)

Atomic structures and compositions of internal interfaces. Progress report, September 1, 1992--August 31, 1993

Description: This research program addresses fundamental questions concerning the relations between atomic structures and compositions of homophase and heterophase interfaces. Metal/ceramic heterophase interfaces are created via the process of internal oxidation of metallic alloys. The interfaces are studied via a combination of conventional transmission electron microscopy, high resolution electron microscopy, field-ion microscopy and atom probe microscopy. The latter technique is employed to chemically sequence the interfacial region, and to show that the terminating (222) plane of MgO and CdO consists solely of oxygen atoms forthe Cu/MgO (111) and Ag/CdO (111) heterophase interfaces, respectively; this is achieved with no deconvolution of the experimental data. The evolution of metal/ceramic heterophase interfaces is studied by following the process of internal oxidation on an atomic scale from its very earliest stages. It is demonstrated that during the early stages of internal oxidation that metal atom clusters as well as hypo and hyperstoichiometric metal-oxygen clusters are present. Solute-atom segregation to grain boundaries is studied in binary metal alloys employing the free energy simulations and the overlapping distribution Monte Carlo methodologies for dilute Pt(Au), Cu(Ni) and Pd(Ni) alloys for both twist and tilt boundaries.
Date: May 10, 1993
Creator: Seidman, D. N. & Merkle, K. L.

Audit of the Department of Energy`s contracts with Envirocare of Utah, Inc

Description: The Department of Energy (Department) is responsible for protecting human health and the environment by providing an effective and efficient system that treats, stores, and disposes of Departmental waste. The Department disposes of some of its waste at Envirocare of Utah, Inc., (Envirocare) a commercial treatment and disposal facility in Clive, Utah. The audit objective was to determine whether the Department and its contractors were using the most favorable rates available for the disposal of waste at Envirocare. We found that the Department`s contractors did not always use the most favorable rates available. Although volume discounts were available under Departmentwide contracts, two of the Department`s contractors awarded subcontracts to Envirocare with rates that were higher than the Departmentwide rates. This occurred because the Department did not require contractors to use the most favorable rates available. As a result, the Department has incurred unnecessary costs to dispose of contaminated waste. During the audit, one of the contractors reopened negotiations with Envirocare and obtained a lower rate, thereby saving the Department about $3.2 million over the next 3 years. We recommended that the Deputy Assistant Secretary for Environmental Restoration distribute a list of available Departmentwide contracts and rates and direct field activities to require all contractors to use the most favorable rates available to the Department for the treatment and disposal of waste. Management concurred with the finding and recommendation and initiated appropriate action to correct the condition disclosed in the report.
Date: December 10, 1997

B-physics at CDF

Description: During the 1988/1989 run at the Fermilab Tevatron, the CDF detector collected {approx equal}4.1 pb{sup {minus}1} of p{bar p} data at {radical}s = 1.8 TeV. The main goals of this run being physics at high p{sub t}, the CDF trigger was tuned'' for maximizing signals from Z{sup 0}s, Ws, t-quarks, etc. As such, compared to the high p{sub t} physics, the b-physics program was of secondary importance other than that which would be used for background calculations. Also, CDF had no vertex chamber capability for seeing displaced vertices. However, significant b-quark, physics results are evident in two data samples; inclusive electrons and inclusive J/{psi} where J/{psi} {yields} {mu}{sup +}{mu}{sup {minus}}. We can then ask ourselves, given all this, why is it that CDF is able to do b-quark physics The answer is that nature has been kind enough to provide b-quarks at an extremely high rate at the Tevatron. The production cross-section for b{bar b} production is quite large. In the rest of this paper, I will try to specify the goals for b-physics using the inclusive electrons and J/{psi} signals for the 1988/1989 data set. I will then provide a brief look at the data, and will finish with some highly speculative guesses as to whether or not experiments at the Tevatron which look for CP violation in the b sector are possible.
Date: December 10, 1990
Creator: Baden, A.R. (Harvard Univ., Cambridge, MA (USA))

B Plant canyon sample TK-21-1 analytical results for the final report

Description: This document is the analytical laboratory report for the TK-21-1 sample collected from the B Plant Canyon on February 18, 1998. The sample was analyzed in accordance with the Sampling and Analysis Plan for B Plant Solutions (SAP) (Simmons, 1997) in support of the B Plant decommissioning project. Samples were analyzed to provide data both to describe the material which would remain in the tanks after the B Plant transition is complete and to determine Tank Farm compatibility. The analytical results are included in the data summary table (Table 1).
Date: April 10, 1998
Creator: Steen, F.H.

B{sup degree}{sub d} mixing and CP violation measurements at the Tevatron

Description: The authors present six time-dependent B{sub d}{sup 0} mixing measurements of {Delta}m{sub d} from the CDF Run I data. The CDF average is {Delta}m{sub d} = .494{sub {+-} 0.26}{sup {+-} 0.26}(ps){sup {minus}1}. They also present a measurement of the CP-violating asymmetry sin (2{beta}) using a sample of B{sup 0}/{bar B}{sup 0} {r_arrow} J/{psi}K{sub s}{sup 0} decays and report sin(2{beta}) = .79{sub {minus}.44}{sup +.41}.
Date: June 10, 1999
Creator: Byrum, K. L.

Back-Contact Crystalline-Silicon Solar Cells and Modules

Description: This paper summarizes recent progress in the development of back-contact crystalline-silicon (c-Si) solar cells and modules at Sandia National Laboratories. Back-contact cells have potentially improved efficiencies through the elimination of grid obscuration and allow for significant simplifications in the module assembly process. Optimization of the process sequence has improved the efficiency of our back-contact cell (emitter wrap through) from around 12% to near 17% in the past 12 months. In addition, recent theoretical work has elucidated the device physics of emitter wrap-through cells. Finally, improvements in the assembly processing back-contact cells are described.
Date: March 10, 1999
Creator: Bode, M.D.; Garrett, S.E.; Gee, J.M.; Jimeno, J.C. & Smith, D.D.

Balanced Budget Act: Any Proposed Fee-for-Service Payment Modifications Need Thorough Evaluation

Description: Testimony issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO discussed the effect of the Balanced Budget Act of 1997 (BBA) on the Medicare Fee-for-Service Program, focusing on the: (1) payment reforms for providers under the fee-for-service portion of the program; and (2) changes made to skilled nursing facility (SNF) and home health agency (HHA) payment policies."
Date: June 10, 1999
Creator: United States. General Accounting Office.

Beam control and laser characterization for NIF

Description: The demanding energy, power, pulse shape, focusability, pointing, and availability requirements placed on the 192 National Ignition Facility (NIF) beams lead to the need for an automatic operation capability that is well beyond that of previous inertial confinement fusion (ICF) lasers. Alignment, diagnostic, and wavefront correction subsystems are integrated in an approach that, by permitting maximal sharing of instrumentation between subsystems, meets performance requirements at a reasonable cost.
Date: June 10, 1998
Creator: Boege, S. J., LLNL

Beam Profile Measurement at 30 GeV Using Optical Transition Radiation

Description: We present results of measurements of spot size and angular divergence of a 30 GeV electron beam through use of optical transition radiation (OTR). The OTR near field pattern and far field distribution are measured as a function of beam spot size and divergence at wavelengths of 441, 532, and 800 nm, for both the single and double foil configurations. Electron beam spot sizes of 50 {micro}m rms have been resolved, demonstrating the utility of OTR for measurement of small beam spot sizes of high energy (30 GeV) electron beams. Two-foil interference was clearly observed and utilized electron beam angular divergences of {approximately} 100 {micro}rad.
Date: July 10, 1999
Creator: Whittum, David H