Broadband diffractive lens (open access)

Broadband diffractive lens

Significant progress has been made toward solving the century-old problem of chromatic aberrations in diffractive optics. Our approach exploits modern materials and microfabrication technology and is very different from the purely diffractive strategy,'' which is commonly employed and which results in multiple diffractive elements separated by a finite distance. We have developed a Fresnel zone plate lens comprised of a serial stack of patterned minus-filters which allows broadband radiation to be focused (or imaged) without longitudinal or transverse chromatic aberrations. 7 refs., 4 figs.
Date: May 28, 1991
Creator: Ceglio, N. M.; Hawryluk, A. M.; London, R. A.; Seppala, L. G. (Lawrence Livermore National Lab., CA (USA)) & Gaines, D. P. (Brigham Young Univ., Provo, UT (USA))
Object Type: Article
System: The UNT Digital Library
Colorado State University Program for Developing, Testing, Evaluating and Optimizing Solar Heating and Cooling Systems (open access)

Colorado State University Program for Developing, Testing, Evaluating and Optimizing Solar Heating and Cooling Systems

The objective is to develop and test various integrated solar heating, cooling and domestic hot water systems, and to evaluate their performance. Systems composed of new, as well as previously tested, components are carefully integrated so that effects of new components on system performance can be clearly delineated. The SEAL-DOE program includes six tasks which have received funding for the 1991--92 fifteen-month period. These include: (1) a project employing isothermal operation of air and liquid solar space heating systems; (2) a project to build and test several generic solar water heaters; (3) a project that will evaluate advanced solar domestic hot water components and concepts and integrate them into solar domestic hot water systems; (4) a liquid desiccant cooling system development project; (5) a project that will perform system modeling and analysis work on solid desiccant cooling systems research; and (6) a management task. The objectives and progress in each task are described in this report. 6 figs.
Date: October 28, 1991
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Radiation effects on structural materials (open access)

Radiation effects on structural materials

This report discusses the following topics on the effect radiation has on thermonuclear reactor materials: Atomic Displacements; Microstructure Evolution; Materials Engineering, Mechanics, and Design; Research on Low-Activation Steels; and Research Motivated by Grant Support.
Date: June 28, 1991
Creator: Ghoniem, N. M.
Object Type: Report
System: The UNT Digital Library
Development of improved iron Fischer-Tropsch catalysts (open access)

Development of improved iron Fischer-Tropsch catalysts

The objective of proposed research is development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance.
Date: October 28, 1991
Creator: Bukur, D.B.
Object Type: Report
System: The UNT Digital Library
Liquid Phase Methanol LaPorte Process Development Unit: Modification Operation, and Support Studies (open access)

Liquid Phase Methanol LaPorte Process Development Unit: Modification Operation, and Support Studies

In April 1987, Air Products started the third and final contract with the US Department of Energy to develop the Liquid Phase Methanol (LPMEOH) process. One of the objectives was to identify alternative commercial catalyst(s) for the process. This objective was strategically important as we want to demonstrate that the LPMEOH process is flexible and not catalyst selection limited. Among three commercially available catalysts evaluated in the lab, the catalyst with a designation of F21/0E75-43 was the most promising candidate. The initial judging criteria included not only the intrinsic catalyst activity but also the ability to be used effectively in a slurry reactor. The catalyst was then advanced for a 40-day life test in a laboratory 300 cc autoclave. The life test result also revealed superior stability when compared with that of a standard catalyst. Consequently, the new catalyst was recommended for demonstration in the Process Development Unit (PDU) at LaPorte, Texas. This report details the methodology of testing and selecting the catalyst.
Date: January 28, 1991
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Liquid Phase Methanol LaPorte Process Development Unit: Modification, Operation, and Support Studies (open access)

Liquid Phase Methanol LaPorte Process Development Unit: Modification, Operation, and Support Studies

The LPMEOH process was conceived and patented by Chem Systems Inc. in 1975. Initial research and studies on the process focused on two distinct modes of operation. The first was a liquid fluidized mode with relatively large catalyst pellets suspended in a fluidizing liquid, and the second was an entrained (slurry) mode with fine catalyst particles slurried in an inert liquid. The development of both operating modes progressed in parallel from bench scale reactors, through an intermediate scale lab PDU, and then to the LaPorte PDU in 1984. The slurry mode of operation was ultimately chosen as the operating mode of choice due to its superior performance.
Date: February 28, 1991
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Thermal effects and mirror surface figure requirements for a diagnostic beamline at the Advanced Light Source (open access)

Thermal effects and mirror surface figure requirements for a diagnostic beamline at the Advanced Light Source

An imaging beamline based on a Kirkpatrick-Baez mirror configuration has been designed to image the electron beam in the ALS storage ring, to measure its size and shape. The electron beam emittance will be small ({epsilon}h = 3.4 {times} 10{sup {minus}9} m rad) and the quality of the image is extremely sensitive to surface figure distortion of the mirrors. Thermal distortions and surface temperatures have been calculated for radiatively cooled mirrors of various materials in a search for a simple design which avoids water cooling. The choice of mirror material and the thermal and mechanical design is discussed. 6 refs.
Date: October 28, 1991
Creator: Warwick, T. (Lawrence Berkeley Lab., CA (United States)) & Sharma, S. (Brookhaven National Lab., Upton, NY (United States))
Object Type: Article
System: The UNT Digital Library
Cooperative research in coal liquefaction (open access)

Cooperative research in coal liquefaction

Significant progress was made in the May 1990--May 1991 contract period in three primary coal liquefaction research areas: catalysis, structure-reactivity studies, and novel liquefaction processes. A brief summary of the accomplishments in the past year in each of these areas is given.
Date: May 28, 1991
Creator: Huffman, G. P. & Sendlein, L. V. A. (eds.)
Object Type: Report
System: The UNT Digital Library
Advanced Light Source beam position monitor (open access)

Advanced Light Source beam position monitor

The Advanced Light Source (ALS) is a synchrotron radiation facility nearing completion at LBL. As a third-generation machine, the ALS is designed to produce intense light from bend magnets, wigglers, and undulators (insertion devices). The facility will include a 50 MeV electron linear accelerator, a 1.5 GeV booster synchrotron, beam transport lines, a 1--2 GeV storage ring, insertion devices, and photon beam lines. Currently, the beam injection systems are being commissioned, and the storage ring is being installed. Electron beam position monitors (BPM) are installed throughout the accelerator and constitute the major part of accelerator beam diagnostics. The design of the BPM instruments is complete, and 50 units have been constructed for use in the injector systems. We are currently fabricating 100 additional instruments for the storage ring. In this paper I discuss engineering fabrication, testing and performance of the beam pickup electrodes and the BPM electronics.
Date: October 28, 1991
Creator: Hinkson, J.
Object Type: Article
System: The UNT Digital Library
Water cooled metal optics for the Advanced Light Source (open access)

Water cooled metal optics for the Advanced Light Source

The program for providing water cooled metal optics for the Advanced Light Source at Berkeley is reviewed with respect to fabrication and metrology of the surfaces. Materials choices, surface figure and smoothness specifications, and metrology systems for measuring the plated metal surfaces are discussed. Results from prototype mirrors and grating blanks will be presented, which show exceptionally low microroughness and mid-period error. We will briefly describe out improved version of the Long Trace Profiler, and its importance to out metrology program. We have completely redesigned the mechanical, optical and computational parts of the profiler system with the cooperation of Peter Takacs of Brookhaven, Continental Optical, and Baker Manufacturing. Most important is that one of our profilers is in use at the vendor to allow testing during fabrication. Metrology from the first water cooled mirror for an ALS beamline is presented as an example. The preplating processing and grinding and polishing were done by Tucson Optical. We will show significantly better surface microroughness on electroless nickel, over large areas, than has been reported previously.
Date: October 28, 1991
Creator: McKinney, W.R.; Irick, S.C. (Lawrence Berkeley Lab., CA (United States)) & Lunt, D.L.J. (Tucson Optical Research Corp., AZ (United States))
Object Type: Article
System: The UNT Digital Library
Modeling the absorption of intense, short laser pulses in steep density gradients (open access)

Modeling the absorption of intense, short laser pulses in steep density gradients

A subroutine which calculates the absorption of short pulse electromagnetic radiation in a material has been installed into the laser fusion modeling program called LASNEX. Calculational results show the necessity for NLTE physics to account for ionization, the development of non-exponential density profiles for the expanding plasma and movement of the critical point toward the surface which results in Doppler shifts of the reflected light. Comparison of calculations of local scale lengths with experiments shows not only good agreement but the correct scaling with intensity. 8 refs., 5 figs.
Date: January 28, 1991
Creator: Alley, W.E.
Object Type: Article
System: The UNT Digital Library
Ultrasonic cleaning of depleted uranium material as an alternative to nitric acid cleaning (open access)

Ultrasonic cleaning of depleted uranium material as an alternative to nitric acid cleaning

Nitric acid is used to clean depleted uranium in the form of cast billets, and cast and wrought parts in the processing cycle and is the largest contributor of waste to the West End Treatment Facility (WETF). An estimated 27,000 gallons of liquid and 75 to 95% of all uranium received was sent to the WETF for processing from this facility in our baseline year. Because wrought parts account for the largest throughput at the nitric acid facility, an alternative cleaning method for these parts was examined first. Test results on the first part type from the wrought family showed ultrasonic cleaning to be an effective cleaning method. Since the geometry for this part presented the most difficulty in terms of ultrasonic cleaning, the entire wrought family is expected to be moved from the nitric acid facility to the ultrasonic cleaning facility. As a result, there will be an 83% reduction part throughput at the nitric acid facility which corresponds to a significant decrease in wastes sent to the WETF and a reduction in the generation and associated costs of waste overall. This change also eliminated two building moves involving two RAD areas resulting in a part movement reduction of …
Date: May 28, 1991
Creator: Frye, L.E. & Senviel, C.B.
Object Type: Report
System: The UNT Digital Library
Molecular mechanisms in radiation damage to DNA (open access)

Molecular mechanisms in radiation damage to DNA

The objectives of this work are to elucidate the molecular mechanisms that are responsible for radiation-induced DNA damage. The overall goal is to understand the relationship between the chemical and structural changes produced by ionizing radiation in DNA and the resulting impairment of biological function expressed as carcinogenesis or cell death. The studies are based on theoretical explorations of possible mechanisms that link initial radiation damage in the form of base and sugar damage to conformational changes in DNA. These mechanistic explorations should lead to the formulation of testable hypothesis regarding the processes of impairment of regulation of gene expression, alternation in DNA repair, and damage to DNA structure involved in cell death or cancer.
Date: October 28, 1991
Creator: Osman, R.
Object Type: Report
System: The UNT Digital Library
(Efficient identification and analysis of low and medium frequency repeats) (open access)

(Efficient identification and analysis of low and medium frequency repeats)

The effective starting date of this grant was May 15. In the first three months of this project we focused primarily on organizational and technical aspects of our research which included: organization of the database of repeats in primates; preparation of software for rapid and sensitive search of novel repetitive elements in GenBank; purchase and installation of the Sun workstation; and research on the mammal-specific MAR1 family of repetitive elements (to be communicated in October).
Date: August 28, 1991
Creator: Jurka, J.
Object Type: Report
System: The UNT Digital Library
Contract administration involving the remedial investigation and feasibility study at the Feed Materials Production Center (open access)

Contract administration involving the remedial investigation and feasibility study at the Feed Materials Production Center

Advanced Sciences, Incorporated (ASI), has been performing a Remedial Investigation and Feasibility Study (RI/FS) at the Feed Materials Production Center (Fernald Facility) at Fernald, Ohio, under an 8 (a) contract with the US Small Business Administration (SBA). The Fernald Facility is a Government-owned facility operated by Westinghouse Materials Company of Ohio (WMCO) under a management and operating contract. The objective of this audit was to evaluate the award and administration of the ASI contract.
Date: August 28, 1991
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Syntheses and structural characterization of zirconium-tin and zirconium-lead binary and ternary systems (open access)

Syntheses and structural characterization of zirconium-tin and zirconium-lead binary and ternary systems

The binary zirconium-tin system was reinvestigated. The A15 phase appears to be a line phase with a Zr{sub 4}Sn composition. The Zr{sub 5}Sn{sub 3} (Mn{sub 5}Si{sub 3}-type) and Zr{sub 5}Sn{sub 4} (Ti{sub 5}Ga{sub 4}-type) compounds are line phases below 1000{degree}C, the latter being a self-interstitial phase of the former. ZrSn{sub 2} is the tin-richest phase. There is an one-phase region between these phases with partial self-interstitials at high temperatures. The zirconium-lead system behaves similarly: there are an A15 phase with a Zr{sub {approximately}5.8}Pb composition, Zr{sub 5}Pb{sub 3} (Mn{sub 5}Si{sub 3}-type) and Zr{sub 5}Pb{sub 4} (Ti{sub 5}Ga{sub 4-type}) compounds, and a high temperature solid solution between Zr{sub 5}Pb{sub >3.5} and Zr{sub 5}Pb{sub 4} from below 1000{degree}C; however, the ZrSn{sub 2} analogue is not formed. The Mn{sub 5}Si{sub 3}-type phases in these systems can accommodate third elements interstitially to form stoichiometric compounds Zr{sub 5}Sn{sub 3}Z (Z = B, C, N, O, Al, Si, P, S, Cu, Zn, Ga, Ge, and As and Se) and Zr{sub 5}Pb{sub 3}Z (Z = Al, Si, P, S, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Se, Ag, Cd, In, Sn, Sb and Te) as well as their self-interstitial derivatives. The systems Zr-Sn-T, T = Fe, Co …
Date: January 28, 1991
Creator: Kwon, Y.U.
Object Type: Report
System: The UNT Digital Library
Advective diffusive/dispersive transport in geochemical processes (open access)

Advective diffusive/dispersive transport in geochemical processes

Comprehensive understanding of chemical transport in response to fluid flow and diffusion in geologic processes requires thermodynamic and transport properties of a wide variety of aqueous species at the temperature and pressure of interest, as well as mass transfer computer codes that provide simultaneously for fluid flow, diffusion, dispersion, homogeneous chemical reactions, and mineral solubilities. As a result of research carried out with support from DOE in prior years of this grant, considerable progress has been made in developing computer codes to calculate advective-dispersive-diffusional transport at both high and low pressures and temperatures. These codes have become highly sophisticated, but their application to geochemical processes is limited by the availability of thermodynamic and transport data for the major solute species in the aqueous phase. Over the past three years, research has been directed primarily toward characterizing the thermodynamic behavior of concentrated supercritical aqueous electrolyte solutions and predicting the diffusion coefficients of organic species in oil field brines. Related research has been concerned with characterizing the growth rate of hydrothermal alteration zones and assessing the relative importance of aqueous diffusion and heterogeneous reactions at mineral surfaces in geochemical processes. 103 refs., 12 figs.
Date: May 28, 1991
Creator: Helgeson, H. C.
Object Type: Report
System: The UNT Digital Library
Catalytic studies on a novel synthesis of methanol (open access)

Catalytic studies on a novel synthesis of methanol

Catalytic studies on a new method for methanol synthesis from CO and H{sub 2} in a slurry reactor are described. This reaction proceeds through the carbonylation of methanol to methyl formate in the liquid phase followed by hydrogenolysis of methyl formate to two molecules of methanol; the net result is the reaction of CO with H{sub 2} to give methanol. Moderate temperatures and pressures (100--160{degrees}C, 50--65 atm) are used. Reaction rates using mixed catalysts comprised of an alkali methoxide and Cu-chromite are presented. It seems likely that Cu-chromite maintains the activity of the alkali methoxide catalyst. A mixed catalyst comprised of potassium methoxide and Cu-chromite was found to be the most active under the reaction conditions used. Evidence is provided for an interaction between the alkali methoxide and Cu-chromite. 27 refs., 6 figs., 2 tabs.
Date: June 28, 1991
Creator: Palekar, V.M.; Tierney, J.W. & Wender, I.
Object Type: Article
System: The UNT Digital Library
Liquid Phase Methanol LaPorte Process Development Unit: Modification, Operation, and Support Studies. Task 2.2: Process Variable Scan Run E-8 and in-Situ Activation With Syngas Run E-9 (open access)

Liquid Phase Methanol LaPorte Process Development Unit: Modification, Operation, and Support Studies. Task 2.2: Process Variable Scan Run E-8 and in-Situ Activation With Syngas Run E-9

The LPMEOH process was conceived and patented by Chem Systems Inc. in 1975. Initial research and studies on the process focused on two distinct modes of operation. The first was a liquid fluidized mode with relatively large catalyst pellets suspended in a fluidizing liquid, and the second was an entrained (slurry) mode with fine catalyst particles slurried in an inert liquid. The development of both operating modes progressed in parallel from bench scale reactors, through an intermediate scale lab PDU, and then to the LaPorte PDU in 1984. The slurry mode of operation was ultimately chosen as the operating mode of choice due to its superior performance.
Date: February 28, 1991
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Advanced Light Source Beam Position Monitor (open access)

Advanced Light Source Beam Position Monitor

The Advanced Light Source (ALS) is a synchrotron radiation facility nearing completion at LBL. As a third-generation machine, the ALS is designed to produce intense light from bend magnets, wigglers, and undulators (insertion devices). The facility will include a 50 MeV electron linear accelerator, a 1.5 GeV booster synchrotron, beam transport lines, a 1--2 GeV storage ring, insertion devices, and photon beam lines. Currently, the beam injection systems are being commissioned, and the storage ring is being installed. Electron beam position monitors (BPM) are installed throughout the accelerator and constitute the major part of accelerator beam diagnostics. The design of the BPM instruments is complete, and 50 units have been constructed for use in the injector systems. We are currently fabricating 100 additional instruments for the storage ring. In this paper I discuss engineering fabrication, testing and performance of the beam pickup electrodes and the BPM electronics.
Date: October 28, 1991
Creator: Hinkson, J.
Object Type: Article
System: The UNT Digital Library
Thermal effects and mirror surface figure requirements for a diagnostic beamline at the Advanced Light Source (open access)

Thermal effects and mirror surface figure requirements for a diagnostic beamline at the Advanced Light Source

An imaging beamline based on a Kirkpatrick-Baez mirror configuration has been designed to image the electron beam in the ALS storage ring, to measure its size and shape. The electron beam emittance will be small ({epsilon}h = 3.4 {times} 10{sup {minus}9} m rad) and the quality of the image is extremely sensitive to surface figure distortion of the mirrors. Thermal distortions and surface temperatures have been calculated for radiatively cooled mirrors of various materials in a search for a simple design which avoids water cooling. The choice of mirror material and the thermal and mechanical design is discussed. 6 refs.
Date: October 28, 1991
Creator: Warwick, T. & Sharma, S.
Object Type: Article
System: The UNT Digital Library
Development of improved iron Fischer-Tropsch catalysts. Quarterly technical progress report, 1 July 1991--30 September 1991 (open access)

Development of improved iron Fischer-Tropsch catalysts. Quarterly technical progress report, 1 July 1991--30 September 1991

The objective of proposed research is development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance.
Date: October 28, 1991
Creator: Bukur, D. B.
Object Type: Report
System: The UNT Digital Library
Harmonics suppression in electromagnets with application to the ALS storage ring corrector magnet design (open access)

Harmonics suppression in electromagnets with application to the ALS storage ring corrector magnet design

This memo presents an analytical development for prediction of skew harmonics in a iron core C-magnet to due arbitrarily positioned electromagnet coils. A structured approach is presented for the suppression of an arbitrary number of harmonic components to arbitrarily low values. Application of the analytical harmonic strength calculations coupled to the structured harmonic suppression approach is presented in the context of the design of the ALS storage ring corrector magnets.
Date: January 28, 1991
Creator: Schlueter, R. D.
Object Type: Report
System: The UNT Digital Library
Harmonics suppression in electromagnets with application to the ALS storage ring corrector magnet design (open access)

Harmonics suppression in electromagnets with application to the ALS storage ring corrector magnet design

This memo presents an analytical development for prediction of skew harmonics in a iron core C-magnet to due arbitrarily positioned electromagnet coils. A structured approach is presented for the suppression of an arbitrary number of harmonic components to arbitrarily low values. Application of the analytical harmonic strength calculations coupled to the structured harmonic suppression approach is presented in the context of the design of the ALS storage ring corrector magnets.
Date: January 28, 1991
Creator: Schlueter, R. D.
Object Type: Report
System: The UNT Digital Library