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1.06 μm 150 psec laser damage study of diamond turned, diamond turned/ polished and polished metal mirrors (open access)

1.06 μm 150 psec laser damage study of diamond turned, diamond turned/ polished and polished metal mirrors

Using a well characterized 1.06 μm 150 ps glass laser pulse the damage characteristics for diamond turned, diamond turned/ polished, and polished copper and silver mirrors less than 5 cm diameter were studied. Although most samples were tested with a normal angle of incidence, some were tested at 45$sup 0$ with different linear polarization showing an increase in damage threshold for S polarization. Different damage mechanisms observed will be discussed. Laser damage is related to residual surface influences of the fabrication process. First attempts to polish diamond turned surfaces resulted in a significant decrease in laser damage threshold. The importance of including the heat of fusion in the one dimensional heat analysis of the theoretical damage threshold and how close the samples came to the theoretical damage threshold is discussed. (auth)
Date: July 24, 1975
Creator: Saito, T. T.; Milam, D.; Baker, P. & Murphy, G.
System: The UNT Digital Library
3-D Hydrodynamic Modeling in a Geospatial Framework (open access)

3-D Hydrodynamic Modeling in a Geospatial Framework

3-D hydrodynamic models are used by the Savannah River National Laboratory (SRNL) to simulate the transport of thermal and radionuclide discharges in coastal estuary systems. Development of such models requires accurate bathymetry, coastline, and boundary condition data in conjunction with the ability to rapidly discretize model domains and interpolate the required geospatial data onto the domain. To facilitate rapid and accurate hydrodynamic model development, SRNL has developed a pre- and post-processor application in a geospatial framework to automate the creation of models using existing data. This automated capability allows development of very detailed models to maximize exploitation of available surface water radionuclide sample data and thermal imagery.
Date: August 24, 2006
Creator: Bollinger, J.; Alfred Garrett, A.; Larry Koffman, L. & David Hayes, D
System: The UNT Digital Library
[5,10,15,20-Tetrakis (4-methoxyphenyl)-porphyrinato] zinc dichloromethane disolvate (open access)

[5,10,15,20-Tetrakis (4-methoxyphenyl)-porphyrinato] zinc dichloromethane disolvate

Article on 5,10,15,20-tetrakis(4-methoxyphenyl)-porphyrinato] zinc dichloromethane disolvate.
Date: July 24, 2013
Creator: McGill, Sean; Nesterov, Vladimir N. & Gould, Stephanie L.
System: The UNT Digital Library
5-Cyano-1,3-phenylene diacetate (open access)

5-Cyano-1,3-phenylene diacetate

This article discusses 5-cyano-1,3-phenylene diacetate.
Date: May 24, 2014
Creator: Abbassi, Bahar; Brumfield, Michela; Jones, Lloyd M.; Nesterov, Vladimir N. & Carr, Andrew J.
System: The UNT Digital Library
A 10 GHz BANDWIDTH, SINGLE TRANSIENT, DIGITIZED OSCILLOSCOPE WITH 20 GHz CAPABILITY (open access)

A 10 GHz BANDWIDTH, SINGLE TRANSIENT, DIGITIZED OSCILLOSCOPE WITH 20 GHz CAPABILITY

EG&G/EM has developed an oscilloscope with a {minus}3 dB bandwidth greater than 10 GHz. Its rolloff characteristics are such that single-transient data greater than 20 GHz may be captured. A demountable CCD camera records the oscilloscope trace and is provided with PC-compatible capture and data processing software. The capabilities of the oscilloscope, camera, and its processing software are described and examples of the system`s performance is shown.
Date: January 24, 1994
Creator: Hudson, C. L.; Kocimski, S. M.; Spector, J.; Thomas, J. B. & Woodstra, R. R.
System: The UNT Digital Library
400 MeV upgrade for the Fermilab linac (open access)

400 MeV upgrade for the Fermilab linac

Fermilab has plans for a comprehensive accelerator upgrade to open new possibilities for both the fixed target and collider experimental programs. An early step in this program is to increase the energy of the linac from 200 to 400 MeV by replacing the last four of its nine 201 MHz Alvarez tanks with twenty-eight 805 MHz side-coupled cavity chains operating at about 8 MV/m average axial field. The principal purpose is to reduce the incoherent spacecharge tuneshift at injection into the Booster which currently limits both the brightness of the beam, an important determinant of collider luminosity, and total intensity to produce both the antiprotons for the collider and the beams to fixed target experimental areas. Other consequences of higher Booster injection energy expected to contribute to some degree of higher intensity limits and improved operational characteristics include improved quality of the guide field at injection, reduced frequency swing for the rf systems, and smaller emittance for the injected beam. The linac upgrade project has moved from a 1986 study through a development project including structure models and numerical studies to a full-feature module prototyping starting this year.
Date: March 24, 1989
Creator: MacLachlan, J.A.
System: The UNT Digital Library
1987 Gordon Research Conference on Physical Metallurgy. (open access)

1987 Gordon Research Conference on Physical Metallurgy.

None
Date: July 24, 1987
Creator: unknown
System: The UNT Digital Library
2009 MICROBIAL POPULATION BIOLOGY GORDON RESEARCH CONFERENCES JULY 19-24,2009 (open access)

2009 MICROBIAL POPULATION BIOLOGY GORDON RESEARCH CONFERENCES JULY 19-24,2009

The 2009 Gordon Conference on Microbial Population Biology will cover a diverse range of cutting edge issues in the microbial sciences and beyond. Firmly founded in evolutionary biology and with a strongly integrative approach, past Conferences have covered a range of topics from the dynamics and genetics of adaptation to the evolution of mutation rate, community ecology, evolutionary genomics, altruism, and epidemiology. The 2009 Conference is no exception, and will include sessions on the evolution of infectious diseases, social evolution, the evolution of symbioses, experimental evolution, adaptive landscapes, community dynamics, and the evolution of protein structure and function. While genomic approaches continue to make inroads, broadening our knowledge and encompassing new questions, the conference will also emphasize the use of experimental approaches to test hypotheses decisively. As in the past, this Conference provides young scientists and graduate students opportunities to present their work in poster format and exchange ideas with leading investigators from a broad spectrum of disciplines. This meeting is never dull: some of the most significant and contentious issues in biology have been thrashed out here. The 2009 meeting will be no exception.
Date: July 24, 2009
Creator: Dean, Anthony
System: The UNT Digital Library
2012 ROCK DEFORMATION: FEEDBACK PROCESSES IN ROCK DEFORMATION GORDON RESEARCH CONFERENCE, AUGUST 19-24, 2012 (open access)

2012 ROCK DEFORMATION: FEEDBACK PROCESSES IN ROCK DEFORMATION GORDON RESEARCH CONFERENCE, AUGUST 19-24, 2012

Topics covered include: Failure At High Confining Pressure; Fluid-assisted Slip, Earthquakes & Fracture; Reaction-driven Cracking; Fluid Transport, Deformation And Reaction; Localized Fluid Transport And Deformation; Earthquake Mechanisms; Subduction Zone Dynamics And Crustal Growth.
Date: August 24, 2012
Creator: Kelemen, Peter
System: The UNT Digital Library
The 2019 materials by design roadmap (open access)

The 2019 materials by design roadmap

This roadmap article presents an overview of the current state of computational materials prediction, synthesis and characterization approaches, materials design needs for various technologies, and future challenges and opportunities that must be addressed.
Date: October 24, 2018
Creator: Alberi, Kirstin; Buongiorno Nardelli, Marco; Zakutayev, Andriy; Mitas, Lubos; Curtarolo, Stefano; Jain, Anubhav et al.
System: The UNT Digital Library
3w Transmitted Beam Diagnostic at the Omega Laser Facility (open access)

3w Transmitted Beam Diagnostic at the Omega Laser Facility

A 3{omega} transmitted beam diagnostic has been commissioned on the Omega Laser at the Laboratory for Laser Energetics, University of Rochester [Soures et.al., Laser Part. Beams 11 (1993)]. Transmitted light from one beam is collected by a large focusing mirror and directed onto a diagnostic platform. The near field of the transmitted light is imaged; the system collects information from twice the original f-cone of the beam. Two gated optical cameras capture the near field image of the transmitted light. Thirteen spatial positions around the measurement region are temporally resolved using fast photodiodes to allow a measure of the beam spray evolution. The Forward stimulated Raman scattering and forward simulated Brillion scattering are spectrally and temporally resolved at 5 independent locations within twice the original f-cone. The total transmitted energy is measured in two spectral bands ({delta}{lambda} < 400 nm and {delta}{lambda} > 400 nm).
Date: April 24, 2006
Creator: Froula, D. H.; Rekow, V.; Sorce, C.; Piston, K.; Knight, R.; Alvarez, S. et al.
System: The UNT Digital Library
4th generation light source instrumentation. (open access)

4th generation light source instrumentation.

This working group on 4th Generation Light Source (4GLS) Instrumentation was a follow-up to the opening-discussion on Challenges in Beam Profiling. It was in parallel with the Feedback Systems session. We filled the SSRL Conference Room with about 25 participants. The session opened with an introduction by Lumpkin. The target beam parameter values for a few-angstrom, self-amplified spontaneous emissions (SASE) experiment and for a diffraction-limited soft x-ray storage ring source were addressed. Instrument resolution would of course need to be 2-3 times better than the value measured, if possible. The nominal targeted performance parameters are emittance (1-2{pi} mm mrad), bunch length (100 fs), peak-current (l-5 kA), beam size (10 {micro}m), beam divergence (1 {micro}rad), energy spread (2 x 10{sup {minus}4}), and beam energy (10's of GeV). These are mostly the SASE values, and the possible parameters for a diffraction-limited soft x-ray source would be relaxed somewhat. Beam stability and alignment specifications in the sub-micron domain for either device are anticipated.
Date: September 24, 1998
Creator: Lumpkin, A.
System: The UNT Digital Library
9th Diesel Engine Emissions Reduction (DEER) Workshop 2003 (open access)

9th Diesel Engine Emissions Reduction (DEER) Workshop 2003

The PowerTrap{trademark} is a non-exhaust temperature dependent system that cannot become blocked and features a controlled regeneration process independent of the vehicle's drive cycle. The system has a low direct-current power source requirement available in both 12-volt and 24-volt configurations. The system is fully programmable, fully automated and includes Euro IV requirements of operation verification. The system has gained European component-type approval and has been tested with both on- road and off-road diesel fuel up to 2000 parts per million. The device is fail-safe: in the event of a device malfunction, it cannot affect the engine's performance. Accumulated mileage testing is in excess of 640,000 miles to date. Vehicles include London-type taxicabs (Euro 1 and 2), emergency service fire engines (Euro 1, 2, and 3), inner city buses, and light-duty locomotives. Independent test results by Shell Global Solutions have consistently demonstrated 85-99 percent reduction of ultrafines across the 7-35 nanometer size range using a scanning mobility particle sizer with both ultra-low sulfur diesel and off-road high-sulfur fuel.
Date: August 24, 2003
Creator: Kukla, Peter; Wright, James; Harris, Georgina; Ball, Andrew & Gu, Fengshou
System: The UNT Digital Library
Abraham Solvation Parameter Model: Examination of Possible Intramolecular Hydrogen-Bonding Using Calculated Solute Descriptors (open access)

Abraham Solvation Parameter Model: Examination of Possible Intramolecular Hydrogen-Bonding Using Calculated Solute Descriptors

This article calculates Abraham model solute descriptors using published solubility data for 4,5-dihydroxyanthraquinone-2-carboxylic acid dissolved in several organic solvents of varying polarity and hydrogen-bonding character.
Date: July 24, 2022
Creator: Sinha, Sneha; Yang, Chelsea; Wu, Emily & Acree, William E. (William Eugene)
System: The UNT Digital Library
Absolute Bunch Length Measurements at the ALS by Incoherent Synchrotron Radiation Fluctuation Analysis (open access)

Absolute Bunch Length Measurements at the ALS by Incoherent Synchrotron Radiation Fluctuation Analysis

By analyzing the pulse to pulse intensity fluctuations of the radiation emitted by a charge particle in the incoherent part of the spectrum, it is possible to extract information about the spatial distribution of the beam. At the Advanced Light Source (ALS) of the Lawrence Berkeley National Laboratory, we have developed and tested a simple scheme based on this principle that allows for the absolute measurement of the bunch length. A description of the method and the experimental results are presented.
Date: January 24, 2008
Creator: Filippetto, D.; /Frascati; Sannibale, F.; Zolotorev, Max Samuil; /LBL, Berkeley; Stupakov, G.V. et al.
System: The UNT Digital Library
Absorptance measurements of transmissive optical components by the surface thermal lensing technique (open access)

Absorptance measurements of transmissive optical components by the surface thermal lensing technique

The surface thermal lensing technique (STL) successfully resolved and measured the absorptance of transmissive optical components: near- normal angle-of-incidence anti-reflectors and beam splatters. The STL system uses an Ar ion laser to pump the components at 514.5 mn. The absorptance-induced surface deformation diffracts the HeNe probe beam into a photo-detector. The signal intensity was calibrated with a sample of known absorptance. The optical components were designed to function in a copper vapor laser (CVL) transport system, and were previously tested for absorptance with a high power CVL system at 511 rtm. To assure proper absorptance data from the STL system, the pump laser power densities were set at the operational level of the coatings, absorptance time trends were monitored, and absorptance area scans were made. Both types of transmissive optics are more stable than the CVL high reflectors that were measured in another study. Parameter studies based on Fresnel diffraction theory were also performed to optimize experimental condition. The STL system was assessed to have 10 ppb sensitivity for absorption measurement given 2 W of pump power.
Date: September 24, 1997
Creator: Chow, R.; Taylor, J. R.; Wu, Z. L.; Han, Y. & Tian, L. Y.
System: The UNT Digital Library
The accelerated site technology deployment program presents the segmented gate system (open access)

The accelerated site technology deployment program presents the segmented gate system

The Department of Energy (DOE) is working to accelerate the acceptance and application of innovative technologies that improve the way the nation manages its environmental remediation problems. The DOE Office of Science and Technology established the Accelerated Site Technology Deployment Program (ASTD) to help accelerate the acceptance and implementation of new and innovative soil and ground water remediation technologies. Coordinated by the Department of Energy's Idaho Office, the ASTD Program reduces many of the classic barriers to the deployment of new technologies by involving government, industry, and regulatory agencies in the assessment, implementation, and validation of innovative technologies. The paper uses the example of the Segmented Gate System (SGS) to illustrate how the ASTD program works. The SGS was used to cost effectively separate clean and contaminated soil for four different radionuclides: plutonium, uranium, thorium, and cesium. Based on those results, it has been proposed to use the SGS at seven other DOE sites across the country.
Date: February 24, 2000
Creator: PATTESON,RAYMOND; MAYNOR,DOUG & CALLAN,CONNIE
System: The UNT Digital Library
Accelerator Challenges and Opportunities for Future Neutrino Experiments (open access)

Accelerator Challenges and Opportunities for Future Neutrino Experiments

There are three types of future neutrino facilities currently under study, one based on decays of stored beta-unstable ion beams (?Beta Beams?), one based on decays of stored muon beams (?Neutrino Factory?), and one based on the decays of an intense pion beam (?Superbeam?). In this paper we discuss the challenges each design team must face and the R&D being carried out to turn those challenges into technical opportunities. A new program, the Muon Accelerator Program, has begun in the U.S. to carry out the R&D for muon-based facilities, including both the Neutrino Factory and, as its ultimate goal, a Muon Collider. The goals of this program will be briefly described.
Date: December 24, 2010
Creator: Zisman, Michael S
System: The UNT Digital Library
Accelerator Physics Code Web Repository (open access)

Accelerator Physics Code Web Repository

In the framework of the CARE HHH European Network, we have developed a web-based dynamic accelerator-physics code repository. We describe the design, structure and contents of this repository, illustrate its usage, and discuss our future plans, with emphasis on code benchmarking.
Date: October 24, 2006
Creator: Zimmermann, F.; Basset, R.; Bellodi, G.; Benedetto, E.; Dorda, U.; Giovannozzi, M. et al.
System: The UNT Digital Library
Accelerators, Beams And Physical Review Special Topics - Accelerators And Beams (open access)

Accelerators, Beams And Physical Review Special Topics - Accelerators And Beams

Accelerator science and technology have evolved as accelerators became larger and important to a broad range of science. Physical Review Special Topics - Accelerators and Beams was established to serve the accelerator community as a timely, widely circulated, international journal covering the full breadth of accelerators and beams. The history of the journal and the innovations associated with it are reviewed.
Date: October 24, 2011
Creator: Siemann, R. H.
System: The UNT Digital Library
The Acid Hydrolysis Mechanism of Acetals Catalyzed by a Supramolecular Assembly in Basic Solution (open access)

The Acid Hydrolysis Mechanism of Acetals Catalyzed by a Supramolecular Assembly in Basic Solution

A self-assembled supramolecular host catalyzes the hydrolysis of acetals in basic aqueous solution. The mechanism of hydrolysis is consistent with the Michaelis-Menten kinetic model. Further investigation of the rate limiting step of the reaction revealed a negative entropy of activation ({Delta}S{double_dagger} = -9 cal mol{sup -1}K{sup -1}) and an inverse solvent isotope effect (k(H{sub 2}O)/k(D{sub 2}O) = 0.62). These data suggest that the mechanism of hydrolysis that takes place inside the assembly proceeds through an A-2 mechanism, in contrast to the A-1 mechanism operating in the uncatalyzed reaction. Comparison of the rates of acetal hydrolysis in the assembly with the rate of the reaction of unencapsulated substrates reveals rate accelerations of up to 980 over the background reaction for the substrate diethoxymethane.
Date: September 24, 2008
Creator: Pluth, Michael D.; Bergman, Robert G. & Raymond, Kenneth N.
System: The UNT Digital Library
An acoustic analysis of American English liquids by adults and children: Native English speakers and native Japanese speakers of English (open access)

An acoustic analysis of American English liquids by adults and children: Native English speakers and native Japanese speakers of English

This article is a study investigating acoustic characteristics of American English liquids produced by native English (NE) and native Japanese (NJ) speakers reported in Aoyama, Flege, Guion, Akahane-Yamada, and Yamada [(2004). J. Phonetics 32, 233–250]. The secondary aim of the study is to compare the acoustic nature of English liquids between native speakers and Japanese L2 speakers of English. This work was presented at the 170th Meeting of the Acoustical Society of America on June 25, 2017 in Boston, MA.
Date: June 7, 2019
Creator: Aoyama, Katsura; Flege, James E.; Akahane-Yamada, Reiko & Yamada, Tsuneo
System: The UNT Digital Library
Actinic EUV mask inspection beyond 0.25 NA (open access)

Actinic EUV mask inspection beyond 0.25 NA

The SEMATECH Berkeley Actinic Inspection Tool (AIT) is an EUV-wavelength mask inspection microscope designed for direct aerial image measurements, and pre-commercial EUV mask research. Operating on a synchrotron bending magnet beamline, the AIT uses an off-axis Fresnel zoneplate lens to project a high-magnification EUV image directly onto a CCD camera. We present the results of recent system upgrades that have improved the imaging resolution, illumination uniformity, and partial coherence. Benchmarking tests show image contrast above 75% for 100-nm mask features, and significant improvements and across the full range of measured sizes. The zoneplate lens has been replaced by an array of user-selectable zoneplates with higher magnification and NA values up to 0.0875, emulating the spatial resolution of a 0.35-NA 4x EUV stepper. Illumination uniformity is above 90% for mask areas 2-{micro}m-wide and smaller. An angle-scanning mirror reduces the high coherence of the synchrotron beamline light source giving measured {sigma} values of approximately 0.125 at 0.0875 NA.
Date: March 24, 2008
Creator: Goldberg, Kenneth A.; Mochi, Iacopo; Anderson, Erik H.; Rekawa, Seno. B.; Kemp, Charles D.; Huh, S. et al.
System: The UNT Digital Library
Actinic inspection of multilayer defects on EUV masks (open access)

Actinic inspection of multilayer defects on EUV masks

The production of defect-free mask blanks, and the development of techniques for inspecting and qualifying EUV mask blanks, remains a key challenge for EUV lithography. In order to ensure a reliable supply of defect-free mask blanks, it is necessary to develop techniques to reliably and accurately detect defects on un-patterned mask blanks. These inspection tools must be able to accurately detect all critical defects whilst simultaneously having the minimum possible false-positive detection rate. There continues to be improvement in high-speed non-actinic mask blank inspection tools, and it is anticipated that these tools can and will be used by industry to qualify EUV mask blanks. However, the outstanding question remains one of validating that non-actinic inspection techniques are capable of detecting all printable EUV defects. To qualify the performance of non-actinic inspection tools, a unique dual-mode EUV mask inspection system has been installed at the Advanced Light Source (ALS) synchrotron at Lawrence Berkeley National Laboratory. In high-speed inspection mode, whole mask blanks are scanned for defects using 13.5-nm wavelength light to identify and map all locations on the mask that scatter a significant amount of EUV light. In imaging, or defect review mode, a zone plate is placed in the reflected …
Date: March 24, 2005
Creator: Barty, A.; Liu, Y.; Gullikson, E.; Taylor, J. S. & Wood, O.
System: The UNT Digital Library