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Methods of Opacity Calculations

Description: "Methods for calculating the opacity of materials at high temperatures are discussed in this report. Minor improvements are outlined for the treatment of continuous absorption processes, and a small error usually made in treating the scattering process is corrected. In contrast to all previous calculations of opacity, the effect of line absorption is carefully examined, for it may well be the dominant process under certain conditions of temperature and density. Detailed methods for calculating the line absorption contribution are, therefore, developed. To illustrate the principles involved, the opacity of pure iron at a temperature of 1000 volts and normal density is worked out in detail" (p. ii).
Date: 1949
Creator: Mayer, Harris
Partner: UNT Libraries Government Documents Department

Field Errors in Hybrid Insertion Devices

Description: Hybrid magnet theory as applied to the error analyses usedin the design of Advanced Light Source (ALS) insertion devices isreviewed. Sources of field errors in hybrid insertion devices arediscussed.
Date: February 3, 1995
Creator: Schlueter, R.D.
Partner: UNT Libraries Government Documents Department

A Fluorimetric Study of the Thorium-Morin System

Description: A report about the irradiated ultraviolet light emitted when thorium reacts with morin. The effect on the fluorescence of such variables as concentration of acid, alcohol, thorium, morin, and complex; time, temperature, and wavelength of exciting light are studied to determine experimental conditions yielding maximum fluorescence.
Date: April 1956
Creator: Milkey, Robert G. & Fletcher, Mary H.
Partner: UNT Libraries Government Documents Department

Two-Seat Light Airplanes Which Participated in Contest Held at Lympne, England, Week of September 29 to October 4, 1924

Description: Memorandum presenting a description of a competition to produce an airplane suitable for school work. The characteristics evaluated included the speed range, take off, landing, reliability, and high and low speed are provided. A variety of monoplanes and biplanes were entered and a description of each and their blueprints are provided.
Date: November 1924
Partner: UNT Libraries Government Documents Department

Light Aeroplane Engine Development

Description: "It has frequently been stated and written that in order to popularize light aircraft the first essential is the production of a reliable engine capable of being easily maintained and having a long life, at the same time selling at a low figure. It is desired to point out the difficulties in the way of realizing this ideal before remarking on the claims of the various types for adoption" (p. 1).
Date: April 1925
Creator: Fell, L. F. R.
Partner: UNT Libraries Government Documents Department

Light Airplanes Which Participated in Contest at Lympne, England, October, 1923

Description: "The purpose of this memorandum is to present in a concise form a description, with drawings, of the most practical light airplanes participating in the meet at Lympne, England, in October, 1923. Features, which are particularly suitable for this type of aircraft, are described and a special reference is made to achievements which indicate progress and possibilities both from a commercial and a military point of view" (p. 1).
Date: May 1924
Partner: UNT Libraries Government Documents Department

Flow Measurement by Means of Light Interference

Description: "There has been under development for the high-speed wind tunnel of the LFA an optical measuring arrangement for the qualitative and quantitative investigation of flow. By the use of interference measurements, the determination of density at the surface of the bodies being tested in the air stream and in the vicinity of these bodies can be undertaken. The results obtained so far in the simple preliminary investigations show that it is possible, even at a low Reynolds number, to obtain the density field in the neighborhood of a test body by optical means" (p. 1).
Date: August 1949
Creator: Zobel
Partner: UNT Libraries Government Documents Department

Resonant soft X-ray emission spectroscopy of liquids

Description: We present now a possible way to carry out soft-x-rayfluorescence spectroscopy of liquids. The liquid cell has a window toattain compatibility with UHV conditions of the spectrometer andbeamline, The synchrotron radiation enters the liquid cell through a 100nm-thick silicon nitride window and the emitted xrays exit through thesame window. This allows in particular liquid solid interfaces to bestudied. Such a liquid cell has been used to study the electronicstructure of a variety of systems ranging from water solutions ofinorganic salts and inertial drugs to nano materials and actinidecompounds in their wet conditions.
Date: October 27, 2004
Creator: Guo, J.-H.; Augustsson, A.; Englund, C.-J. & Nordgren, J.
Partner: UNT Libraries Government Documents Department

RECENT BEAM MEASUREMENTS AND NEW INSTRUMENTATION AT THE ADVANCED LIGHT SOURCE

Description: The Advanced Light Source (ALS) in Berkeley was the first of the soft x-ray third generation light source ever built, and since 1993 has been in continuous and successful operation serving a large community of users in the VUV and soft x-ray community. During these years the storage ring underwent through several important upgrades that allowed maintaining the performance of this veteran facility at the forefront. The ALS beam diagnostics and instrumentation have followed a similar path of innovation and upgrade and nowadays include most of the modem and last generation devices and technologies that are commercially available and used in the recently constructed third generation light sources. In this paper we will not focus on such already widely known systems, but we will concentrate our effort in the description of some measurements techniques, instrumentation and diagnostic systems specifically developed at the ALS and used during the last few years.
Date: May 5, 2008
Creator: Sannibale, Fernando; Baptiste, Kenneth; Barry, Walter; Chin, Michael; Filippetto, Daniele; Jaegerhofer, Lukas et al.
Partner: UNT Libraries Government Documents Department

Enabling instrumentation and technology for 21st century light sources

Description: We present the summary from the Accelerator Instrumentation and Technology working group, one of the five working groups that participated in the BES-sponsored Workshop on Accelerator Physics of Future Light Sources held in Gaithersburg, MD September 15-17, 2009. We describe progress and potential in three areas: attosecond instrumentation, photon detectors for user experiments, and insertion devices.
Date: June 1, 2010
Creator: Byrd, J.M.; Shea, T.J.; Denes, P.; Siddons, P.; Attwood, D.; Kaertner, F. et al.
Partner: UNT Libraries Government Documents Department

Microstructure evolution of tin under electromigration studied bysynchrotron X-Ray micro-diffraction

Description: Under constant current electromigration, white tin(?-Sn)exhibited a resistance drop of up to 10 percent. It has a body centertetragonal (BCT) structure, and the resistivity along the aand b axes is35 percent smaller than that along the c axis.Microstructure evolutionunder electromigration could be responsible for the resistance drop.Synchrotron radiation white beam x-ray microdiffraction was used to studythis evolution. Both stress and grain orientation was studied.Grain-by-grain analysis was obtained from the diffracted Laue patternsabout the changes of grain orientation during electromigration testing inex-situ and in-situ samples. We observed that high resistance grainsreorient with respect to the neighboring low resistance grains, mostlikely by grain rotation of the latter. A different mechanism ofmicrostructure evolution under electromigration from the normal graingrowth is proposed and discussed.
Date: May 5, 2005
Creator: Wu, Albert T.; Lloyd, J.R.; Tamura, N. & Tu, K.-N.
Partner: UNT Libraries Government Documents Department

Correlation between exchange bias and pinned interfacialspins

Description: Using x-ray magnetic circular dichroism, we have detectedthe very interfacial spins that are responsible for the horizontal loopshift in three different exchange bias sandwiches, chosen because oftheir potential for device applications. The "pinned" uncompensatedinterfacial spins constitute only a fraction of a monolayer and do notrotate in an external magnetic field since they are tightly locked to theantiferromagnetic lattice. A simple extension of the Meiklejohn and Beanmodel is proposed to account quantitatively for the exchange bias fieldsin the three studied systems from the experimentally determined number ofpinned moments and their sizes.
Date: July 1, 2003
Creator: Ohldag, H.; Scholl, A.; Nolting, F.; Arenholz, E.; Maat, S.; Young, A.T. et al.
Partner: UNT Libraries Government Documents Department