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Detection of plasma equilibrium shifts with fiber optic sensing of image currents

Description: The radial equilibrium position of Reverse Field Pinch experiments is determined by the j x B force on the plasma. The current density is that of the toroidal plasma current and the B field is the vertical magnetic field which is present in the plasma. This magnetic field is the result of several components. The main field, generated by the toroidal current windings, is corrected by adjustable trim windings to achieve a desired equilibrium position. There is an additional component to the field… more
Date: January 1, 1988
Creator: Forman, P.R.; Jahoda, F.C. & Miller, G.
Partner: UNT Libraries Government Documents Department
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Capillary liquid chromatography using laser-based and mass spectrometric detection

Description: The research performed during the past year has mainly focused on investigating and minimizing the problems listed below that limit the practical utility of these capillary electrokinetic separation techniques in chemical analysis. (1) Analyses are hindered by poor reproducibility. This is largely a result of complicated and irreproducible capillary wall-solute interactions that often result in adsorption and mobility changes. (2) While the Micellar Electrokinetic Capillary Chromatography techn… more
Date: January 1, 1991
Creator: Sepaniak, M.J. & Cook, K.D.
Partner: UNT Libraries Government Documents Department
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Ultraviolet imaging of hydrogen flames

Description: We have assembled an ultraviolet-sensitive intensified camera for observing hydrogen combustion by imaging the OH, A/sup 2/..sigma.. - X/sup 2//Pi/ bandhead emissions near 309 nm. The camera consists of a quartz and CaF achromat lense-coupled to an ultraviolet image intensifier which is in turn fiber-coupled to a focus projection scan (FPS) vidicon. The emission band is selected with interference filters which serve to discriminate against background. The camera provides optical gain of 100 to … more
Date: January 1, 1988
Creator: Yates, G. J.; Wilke, M. & King, N.
Partner: UNT Libraries Government Documents Department
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Optical fibers and avalanche photodiodes for scintillator counters

Description: Fine hodoscopes can be made of new scintillating optical fibers and one half inch end-on PMT's. An avalanche photodiode with small size and immunity to magnetic fields remains as a tempting new device to be proven as a photodetector for the fibers.
Date: January 1, 1980
Creator: Borenstein, S R; Palmer, R B & Strand, R C
Partner: UNT Libraries Government Documents Department
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Optimization of a VISAR for measuring flyer-plate velocities

Description: VISAR (Velocity Interferometer System for Any Reflector) is commonly used for measuring flyer-plate velocities up to 6 km/s. Flyer plates can travel as much as 1 mm, which is large compared to usual depth-of-focus requirements for VISARs. Flyer plates are explosively driven, or driven by some other very energetic means; as such, they must be tested in a chamber, which will contain the explosion. Routing the laser beam to the chamber and the signal beam to the VISAR can be done safely and easily… more
Date: May 6, 1992
Creator: Sweatt, W. C.; Crump, O. B., Jr. & Brigham, W. P.
Partner: UNT Libraries Government Documents Department
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Phased-array antenna control by a monolithic photonic integrated circuit, COMPASS

Description: Phased-array antenna systems are well known for rapid beam steering and their ability to bring high power to the target. Such systems are also quite complex and heavy, which have limited their usefulness. The issues of weight, size, power use, and complexity have been addressed through a system named COMPASS (Coherent Optical Monolithic Phased Array Steering System). All phased-array antenna systems need: (1) small size; (2) low power use; (3) high-speed beam steering; and (4) digitally-control… more
Date: January 1, 1991
Creator: Kravitz, S. H.; Hietala, V. M.; Vawter, G. A. & Meyer, W. J.
Partner: UNT Libraries Government Documents Department
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Liquid scintillators for optical-fiber applications

Description: A multicomponent liquid scintillator solution for use as a radiation-to-light converter in conjunction with a fiber optic transmission system. The scintillator includes a quantity of 1, 2, 4, 5, 3H, 6H, 1 OH, tetrahydro-8-trifluoromethyl (1) benzopyrano (9, 9a, 1-gh) quinolizin-10-one (Coumarin) as a solute in a fluor solvent such as benzyl alcohol or pseudo-cumene. The use of BIBUQ as an additional or primary solute is also disclosed.
Date: June 1, 1981
Creator: Franks, L. A. & Lutz, S. S.
Partner: UNT Libraries Government Documents Department
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Stress-related phenomena in transient radiation-induced absorption in optical fibers

Description: The optical properties of materials can be modified by exposure to radiation and research to investigate these radiation-induced phenomena has intensified over the last several decades. The advent of optical fiber technology and the many applications of optical fiber for information transmission have sharply increased the interest in these investigations. Optical fibers present a long optical transmission path and that path may traverse different adverse environments, including radiation areas.… more
Date: January 1, 1988
Creator: Looney, L. D.; Lyons, P. B. & Kelly, R. E.
Partner: UNT Libraries Government Documents Department
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Time-Resolved Doubly Bent Crystal X-Ray Spectrometer

Description: X-ray spectroscopy is an essential tool in high temperature plasma research. We describe a time-resolved x-ray spectrometer suitable for measuring spectra in harsh environments common to many very high energy density laboratory plasma sources. The spectrometer consisted of a doubly curved Si(111) crystal diffraction element, a WL-1201 (ZnO:Ga) phosphor, a coherent fiber optic array, and two visible streak cameras. The spectrometer design described here has a minimum time resolution of 1.3 ns wi… more
Date: January 1, 1988
Creator: Hockaday, M. P.; Wilke, M. D.; Blake, R. L.; Vaninetti, J.; Gray, N. T. & Nedrow, P. T.
Partner: UNT Libraries Government Documents Department
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On-line uranium determination using remote fiber fluorimetry

Description: Remote Fiber Fluorimetry (RFF) is being developed at Savannah River Laboratory for the on-line determination of uranium in plant process streams. A prototype system suitable for plant use has been designed and is being built. RFF has four major components: a laser, an optical fiber, an optrode, and a detector. Essentially, an optical fiber carries laser radiation from a laser to a process sampling point. An optrode (the optical analog of an electrode) couples the laser light into a sample solut… more
Date: January 1, 1985
Creator: Malstrom, R A
Partner: UNT Libraries Government Documents Department
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New liquid scintillators for fiber-optic applications

Description: New long-wavelength-emitting, high-speed, liquid scintillators have been developed and tailored specifically for plasma diagnostic experiments employing fiber optics. These scintillators offer significant advantages over commercially available plastic scintillators in terms of sensitivity and bandwidth. FWHM response times as fast as 350 ps have been measured. Emission spectra, time response data, and relative sensitivity information are presented.
Date: January 1, 1981
Creator: Lutz, S. S.; Franks, L. A.; Flournoy, J. M. & Lyons, P. B.
Partner: UNT Libraries Government Documents Department
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Radiation hardening of diagnostics

Description: The world fusion program has advanced to the stage where it is appropriate to construct a number of devices for the purpose of burning DT fuel. In these next-generation experiments, the expected flux and fluence of 14 MeV neutrons and associated gamma rays will pose a significant challenge to the operation and diagnostics of the fusion device. Radiation effects include structural damage to materials such as vacuum windows and seals, modifications to electrical properties such as electrical cond… more
Date: January 1, 1991
Creator: Siemon, R.E.
Partner: UNT Libraries Government Documents Department
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Characterization of low-loss multimode optical fibers for nuclear diagnostics

Description: The application of low loss multimode optical fibers to nuclear diagnostics has been discussed in previous papers. Fiber requirements for this application differ substantially from those for normal communications use. The emphasis for nuclear measurements has been on development of high frequency analog fiber optic transmission line systems, which range from 100 MHz to > 500 MHz signals transmitted at 600 nm and 800 nm, respectively. Accordingly, specialized fiber characterization procedures ov… more
Date: January 1, 1980
Creator: Ogle, J. W.; Nelson, M. A.; Davies, T.J.; Lutz, S.; Lin, C. H.; Theobald, K. et al.
Partner: UNT Libraries Government Documents Department
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Imaging techniques utilizing optical fibers and tomography

Description: Two-dimensional, time-dependent images generated by neutrons, gamma rays, and x-rays incident on fast scintillators are relayed to streak and video cameras over optical fibers. Three dimensions, two spatial and one temporal, have been reduced to two, one in space and time utilizing sampling methods permitting reconstruction of a time-dependent, two-dimensional image subsequent to data recording. The manner in which the sampling is done optimized the ability to reconstruct the image via a maximi… more
Date: January 1, 1985
Creator: Wilke, M.; King, N.S.P.; Gray, N.; Johnson, D.; Esquibel, D.; Nedrow, P. et al.
Partner: UNT Libraries Government Documents Department
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Review of high bandwidth fiber optics radiation sensors

Description: This paper summarizes the use of fiber optics or guided optical systems for radiation sensors. It is limited a passive systems wherein electrical is not required at the sensor location. However, electrically powered light sources, receivers and/or recorders may still be required for detection and data storage in sensor system operation. This paper emphasizes sensor technologies that permit high bandwidth measurements of transient radiation levels, and will also discuss several low bandwidth app… more
Date: January 1, 1985
Creator: Lyons, P. B.
Partner: UNT Libraries Government Documents Department
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Signal enhancement by spectral equalization of high frequency broadband signals transmitted through optical fibers

Description: A new technique is discussed for enhancing the bandwidth and intensity of high frequency (> 1 GHz) analog, spectrally broad (40 nm) signals transmitted through one kilometer of optical fiber. The existing method for bandwidth enhancement of such a signal uses a very narrow (approx. 1 nm) filter between the fiber and detector to limit bandwidth degradation due to material dispersion. Using this method, most of the available optical intensity is rejected and lost. This new technique replaces the … more
Date: January 1, 1980
Creator: Lyons, P. B.; Ogle, J. W. & Holzman, M. A.
Partner: UNT Libraries Government Documents Department
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PHEBUS on-line aerosol monitor development test program

Description: EG G Idaho, Inc. developed an on-line aerosol monitor (OLAM) for the French PHEBUS Fission Product Project. Part of the development was to manufacture and test an OLAM prototype. This report presents the results of the testing which determined the mechanical integrity of the monitor at operating temperature and pressure and performed a preliminary test of the optical system. A series of twenty different tests was conducted during the prototype testing sequence. Since no leaks were detected, the… more
Date: March 1, 1992
Creator: Sprenger, M. H. & Pentecost, C. G.
Partner: UNT Libraries Government Documents Department
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Fiber optic control and diagnostic family of hardwares for the Confinement Physics Research Facility (CPRF) toroidal field and dc interrupter systems

Description: A versatile fiber optic system of outstanding performance has been designed and utilized in the development of the CPRF pulsed power equipment. These fiber optic systems consist of a family of interchangeable, but application oriented, mother and daughter PC boards. Furthermore, a self contained, chassis, or CAMAC'' format of links are available. The transmitter family may be described as having a true instrumentation amplifier front end (of unique design), a temperature compensated V/F convert… more
Date: January 1, 1989
Creator: Reass, W.A. & Schrank, L.S.
Partner: UNT Libraries Government Documents Department
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Design and implementation of a fiber-optic gamma-measurement system

Description: The design and implementation of the downhole portion of a measuring system for gamma rays is presented. Included are three alternative designs for radiation-resistant collimating and condensing lenses, sample cells, turning mirrors, and fiber-optic termination techniques. Also discussed are mechanical mounts and positioners, shielding, alignment, test methods, and field installation. Some general design suggestions for optical systems in adverse environments are also presented.
Date: May 19, 1980
Creator: Reedy, R.P.; Crawford, D.W. & Roeske, F. Jr.
Partner: UNT Libraries Government Documents Department
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Measurement of Faraday rotation in twisted optical fiber using rotating polarization and analog phase detection

Description: We demonstrated phase modulation of rotating linearly polarized light by current-induced Faraday rotation in a single mode optical fiber and used the technique to measure the current in ZT-40M, a Reversed-Field Pinch. We have also demonstrated the practicality of using twisted sensing fiber to overcome the problems associated with linear birefringence.
Date: January 1, 1985
Creator: Chandler, G.I.; Forman, P.R. & Jahoda, F.C.
Partner: UNT Libraries Government Documents Department
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Fiber optic communication links

Description: Fiber optics is a new, emerging technology which offers relief from many of the problems which limited past communications links. Its inherent noise immunity and high bandwidth open the door for new designs with greater capabilities. Being a new technology, certain problems can be encountered in specifying and installing a fiber optic link. A general fiber optic system is discussed with emphasis on the advantages and disadvantages. It is not intended to be technical in nature, but a general dis… more
Date: January 1, 1980
Creator: Meyer, R. H.
Partner: UNT Libraries Government Documents Department
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Reviews of computing technology: Fiber distributed data interface

Description: Fiber Distributed Data Interface, more commonly known as FDDI, is the name of the standard that describes a new local area network (LAN) technology for the 90's. This technology is based on fiber optics communications and, at a data transmission rate of 100 million bits per second (mbps), provides a full order of magnitude improvement over previous LAN standards such as Ethernet and Token Ring. FDDI as a standard has been accepted by all major computer manufacturers and is a national standard a… more
Date: December 1, 1991
Creator: Johnson, A.J.
Partner: UNT Libraries Government Documents Department
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Detection of polyaromatic compounds using antibody-based fiberoptics fluoroimmunosensors

Description: In this work we have investigated the performance of an antibody-based fiberoptics sensor for the detection of the carcinogen benzo(a)pyrene and its DNA-adduct product BP-tetrol. The excellent sensitivity of this device - femtomole limits of detection for BP - illustrates that it has considerable potential to perform analyses of chemical and biological samples at trace levels in complex matrices. The results indicate that fiberoptics-based fluoroimmunosensors can be useful in a wide spectrum of… more
Date: January 1, 1987
Creator: Vo-Dinh, T.; Tromberg, B. J.; Griffin, G. D.; Ambrose, K. R.; Sepaniak, M. J. & Alarie, J. P.
Partner: UNT Libraries Government Documents Department
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