Sample records for fluorescent lighting-minimum efficacy

  1. Fluorescent refrigeration

    DOE Patents [OSTI]

    Epstein, Richard I. (Santa Fe, NM); Edwards, Bradley C. (Los Alamos, NM); Buchwald, Melvin I. (Santa Fe, NM); Gosnell, Timothy R. (Santa Fe, NM)

    1995-01-01T23:59:59.000Z

    Fluorescent refrigeration is based on selective radiative pumping, using substantially monochromatic radiation, of quantum excitations which are then endothermically redistributed to higher energies. Ultimately, the populated energy levels radiatively deexcite emitting, on the average, more radiant energy than was initially absorbed. The material utilized to accomplish the cooling must have dimensions such that the exciting radiation is strongly absorbed, but the fluorescence may exit the material through a significantly smaller optical pathlength. Optical fibers and mirrored glasses and crystals provide this requirement.

  2. Fluorescent refrigeration

    DOE Patents [OSTI]

    Epstein, R.I.; Edwards, B.C.; Buchwald, M.I.; Gosnell, T.R.

    1995-09-05T23:59:59.000Z

    Fluorescent refrigeration is based on selective radiative pumping, using substantially monochromatic radiation, of quantum excitations which are then endothermically redistributed to higher energies. Ultimately, the populated energy levels radiatively deexcite emitting, on the average, more radiant energy than was initially absorbed. The material utilized to accomplish the cooling must have dimensions such that the exciting radiation is strongly absorbed, but the fluorescence may exit the material through a significantly smaller optical pathlength. Optical fibers and mirrored glasses and crystals provide this requirement. 6 figs.

  3. Fluorescent optical position sensor

    DOE Patents [OSTI]

    Weiss, Jonathan D.

    2005-11-15T23:59:59.000Z

    A fluorescent optical position sensor and method of operation. A small excitation source side-pumps a localized region of fluorescence at an unknown position along a fluorescent waveguide. As the fluorescent light travels down the waveguide, the intensity of fluorescent light decreases due to absorption. By measuring with one (or two) photodetectors the attenuated intensity of fluorescent light emitted from one (or both) ends of the waveguide, the position of the excitation source relative to the waveguide can be determined by comparing the measured light intensity to a calibrated response curve or mathematical model. Alternatively, excitation light can be pumped into an end of the waveguide, which generates an exponentially-decaying continuous source of fluorescent light along the length of the waveguide. The position of a photodetector oriented to view the side of the waveguide can be uniquely determined by measuring the intensity of the fluorescent light emitted radially at that location.

  4. Safe biodegradable fluorescent particles

    DOE Patents [OSTI]

    Martin, Sue I. (Berkeley, CA); Fergenson, David P. (Alamo, CA); Srivastava, Abneesh (Santa Clara, CA); Bogan, Michael J. (Dublin, CA); Riot, Vincent J. (Oakland, CA); Frank, Matthias (Oakland, CA)

    2010-08-24T23:59:59.000Z

    A human-safe fluorescence particle that can be used for fluorescence detection instruments or act as a safe simulant for mimicking the fluorescence properties of microorganisms. The particle comprises a non-biological carrier and natural fluorophores encapsulated in the non-biological carrier. By doping biodegradable-polymer drug delivery microspheres with natural or synthetic fluorophores, the desired fluorescence can be attained or biological organisms can be simulated without the associated risks and logistical difficulties of live microorganisms.

  5. Fluorescent lamp with static magnetic field generating means

    DOE Patents [OSTI]

    Moskowitz, P.E.; Maya, J.

    1987-09-08T23:59:59.000Z

    A fluorescent lamp wherein magnetic field generating means (e.g., permanent magnets) are utilized to generate a static magnetic field across the respective electrode structures of the lamp such that maximum field strength is located at the electrode's filament. An increase in efficacy during operation has been observed. 2 figs.

  6. Fluorescent Tube Lamps

    Broader source: Energy.gov [DOE]

    FEMP temporarily suspended its energy efficiency requirements for fluorescent tube lamps as it evaluates the market impact of the pending 2012 minimum efficiency standards for fluorescent lamps. The program will issue updated energy efficiency requirements when the market distribution of this product category stabilizes and when doing so has the potential to result in significant Federal energy savings.

  7. Recombinant fluorescent protein microsphere calibration standard

    DOE Patents [OSTI]

    Nolan, John P. (Santa Fe, NM); Nolan, Rhiannon L. (Santa Fe, NM); Ruscetti, Teresa (Los Alamos, NM); Lehnert, Bruce E. (Los Alamos, NM)

    2001-01-01T23:59:59.000Z

    A method for making recombinant fluorescent protein standard particles for calibration of fluorescence instruments.

  8. Fluorescent filtered electrophosphorescence

    DOE Patents [OSTI]

    Forrest, Stephen (Ann Arbor, MI); Sun, Yiru (Princeton, NJ); Giebink, Noel (Ann Arbor, MI); Thompson, Mark E. (Anaheim Hills, CA)

    2010-08-03T23:59:59.000Z

    The present invention relates to organic light emitting devices (OLEDs), and more specifically to OLEDS that emit light using a combination of fluorescent emitters and phosphorescent emitters for the efficient utilization of all of the electrically generated excitons.

  9. Fluorescent filtered electrophosphorescence

    DOE Patents [OSTI]

    Forrest, Stephen R. (Princeton, NJ); Sun, Yiru (Princeton, NJ); Giebink, Noel (Princeton, NJ); Thompson, Mark E. (Anaheim Hills, CA)

    2009-01-06T23:59:59.000Z

    The present invention relates to organic light emitting devices (OLEDs), and more specifically to OLEDS that emit light using a combination of fluorescent emitters and phosphorescent emitters for the efficient utilization of all of the electrically generated excitons.

  10. Max Tech and Beyond: Fluorescent Lamps

    SciTech Connect (OSTI)

    Scholand, Michael

    2012-04-01T23:59:59.000Z

    Fluorescent lamps are the most widely used artificial light source today, responsible for approximately 70% of the lumens delivered to our living spaces globally. The technology was originally commercialized in the 1930's, and manufacturers have been steadily improving the efficacy of these lamps over the years through modifications to the phosphors, cathodes, fill-gas, operating frequency, tube diameter and other design attributes. The most efficient commercially available fluorescent lamp is the 25 Watt T5 lamp. This lamp operates at 114-116 lumens per watt while also providing good color rendering and more than 20,000 hours of operating life. Industry experts interviewed indicated that while this lamp is the most efficient in the market today, there is still a further 10 to 14% of potential improvements that may be introduced to the market over the next 2 to 5 years. These improvements include further developments in phosphors, fill-gas, cathode coatings and ultraviolet (UV) reflective glass coatings. The commercialization of these technology improvements will combine to bring about efficacy improvements that will push the technology up to a maximum 125 to 130 lumens per watt. One critical issue raised by researchers that may present a barrier to the realization of these improvements is the fact that technology investment in fluorescent lamps is being reduced in order to prioritize research into light emitting diodes (LEDs) and ceramic metal halide high intensity discharge (HID) lamps. Thus, it is uncertain whether these potential efficacy improvements will be developed, patented and commercialized. The emphasis for premium efficacy will continue to focus on T5 lamps, which are expected to continue to be marketed along with the T8 lamp. Industry experts highlighted the fact that an advantage of the T5 lamp is the fact that it is 40% smaller and yet provides an equivalent lumen output to that of a T8 or T12 lamp. Due to its smaller form factor, the T5 lamp contains less material (i.e., glass, fill gas and phosphor), and has a higher luminance, enabling fixtures to take advantage of the smaller lamp size to improve the optics and provide more efficient overall system illuminance. In addition to offering the market a high-quality efficacious light source, another strong value proposition of fluorescent lighting is its long operating life. In today's market, one manufacturer is offering fluorescent lamps that have a rated life of 79,000 hours - which represents 18 years of service at 12 hours per day, 365 days per year. These lamps, operated using a long-life ballast specified by the manufacturer, take advantage of improvements in cathode coatings, fill gas chemistry and pressure to extend service life by a factor of four over conventional fluorescent lamps. It should be noted that this service life is also longer (approximately twice as long) as today's high-quality LED products. The fluorescent market is currently focused on the T5 and T8 lamp diameters, and it is not expected that other diameters would be introduced. Although T8 is a more optimal diameter from an efficacy perspective, the premium efficiency and optimization effort has been focused on T5 lamps because they are 40% smaller than T8, and are designed to operate at a higher temperature using high-frequency electronic ballasts. The T5 lamp offers savings in terms of materials, packaging and shipping, as well as smaller fixtures with improved optical performance. Manufacturers are actively researching improvements in four critical areas that are expected to yield additional efficacy improvements of approximately 10 to 14 percent over the next five years, ultimately achieving approximately 130 lumens per watt by 2015. The active areas of research where these improvements are anticipated include: (1) Improved phosphors which continue to be developed and patented, enabling higher efficacies as well as better color rendering and lumen maintenance; (2) Enhanced fill gas - adjusting proportions of argon, krypton, neon and xenon to optimize performance, while also m

  11. Fluorescent image tracking velocimeter

    DOE Patents [OSTI]

    Shaffer, Franklin D. (Library, PA)

    1994-01-01T23:59:59.000Z

    A multiple-exposure fluorescent image tracking velocimeter (FITV) detects and measures the motion (trajectory, direction and velocity) of small particles close to light scattering surfaces. The small particles may follow the motion of a carrier medium such as a liquid, gas or multi-phase mixture, allowing the motion of the carrier medium to be observed, measured and recorded. The main components of the FITV include: (1) fluorescent particles; (2) a pulsed fluorescent excitation laser source; (3) an imaging camera; and (4) an image analyzer. FITV uses fluorescing particles excited by visible laser light to enhance particle image detectability near light scattering surfaces. The excitation laser light is filtered out before reaching the imaging camera allowing the fluoresced wavelengths emitted by the particles to be detected and recorded by the camera. FITV employs multiple exposures of a single camera image by pulsing the excitation laser light for producing a series of images of each particle along its trajectory. The time-lapsed image may be used to determine trajectory and velocity and the exposures may be coded to derive directional information.

  12. Fluorescence analyzer for lignin

    SciTech Connect (OSTI)

    Berthold, J.W.; Malito, M.L.; Jeffers, L.

    1993-06-01T23:59:59.000Z

    An apparatus for measuring lignin concentration with time resolved fluorescence in an undiluted wood pulp or black liquor sample, on a real-time, in situ basis is described, comprising: light source means for applying excitation light pulses at a selected wavelength and at known time intervals to the undiluted sample for causing the lignin concentration to produce fluorescent emission light with a fluorescence intensity that monotonically decreases in a quenched fluorescence regime; light detector means for measuring the emission light at the known time intervals and establishing signals indicative thereof; switching means for turning said light detector means on at precise specified time intervals after each excitation light pulse; and signal processing means connected to the light source means and the light detector means for comparing intensities of the emission light from the lignin in the quenched fluorescence regime to the intensities of the excitation light pulses on a time resolved basis for providing a measurement of the lignin concentration in the undiluted sample as a function of the time resolved emission light intensity.

  13. Multiphoton Add fluorescent dye

    E-Print Network [OSTI]

    Braun, Paul

    in toluene was prepared at 0.96 w/w. The monomer used was trimethylolpropane triacrylate (TMPTA) (Aldrich in toluene; the toluene was removed by rotovapping. For fluorescence imaging in colloidal crystals the electro-optic modulator is used to regulate the power of the beam, selectively exposing the regions

  14. Optical Shelving: Suppressed Fluorescence

    E-Print Network [OSTI]

    Mould, R A

    2007-01-01T23:59:59.000Z

    The shelving phenomenon of quantum optics, originally observed by Dehmelt, is analyzed in terms of the nRules that are given in another paper. The heuristic value of these rules is apparent because they reveal the mechanism that enforces the suppression of fluorescence during the dark period associated with shelving.

  15. Optical Shelving: Suppressed Fluorescence

    E-Print Network [OSTI]

    Richard A Mould

    2011-04-11T23:59:59.000Z

    The shelving phenomenon of quantum optics, originally observed by Dehmelt, is analyzed in terms of the qRules that are given in another paper. The heuristic value of these rules is apparent because they not only describe the dark period during shelving, but they reveal the mechanism that enforces the suppression of fluorescence during that time.

  16. Fluorescent Protein Applications in Microscopy

    E-Print Network [OSTI]

    Straight, Aaron

    . The Identification of Green Fluorescent Protein III. Formation of the GFP Chromophore IV. The Structure of GFP V environment. II. The Identification of Green Fluorescent Protein The isolation of green fluorescent protein of Aequorea, Shimomura et al. noted that the lumines- cence from aequorin was blue rather than the green

  17. Renewable Surface Fluorescence Sandwich Immunoassay Biosensor...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Renewable Surface Fluorescence Sandwich Immunoassay Biosensor for Rapid Sensitive Botulinum Toxin Detection in an Automated Renewable Surface Fluorescence Sandwich Immunoassay...

  18. Single-molecule Fluorescence Spectroelectrochemistry of Cresyl...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Fluorescence Spectroelectrochemistry of Cresyl Violet. Abstract: We coupled scanning fluorescence microscopy with a potentiostat via a three-electrode electrochemical...

  19. Compact fluorescent lamp using horizontal and vertical insulating septums and convective venting geometry

    DOE Patents [OSTI]

    Siminovitch, M.

    1998-02-10T23:59:59.000Z

    A novel design is described for a compact fluorescent lamp, including a lamp geometry which will increase light output and efficacy of the lamp in a base down operating position by providing horizontal and vertical insulating septums positioned in the ballast compartment of the lamp to provide a cooler coldspot. Selective convective venting provides additional cooling of the ballast compartment. 9 figs.

  20. The Air-Fluorescence Yield

    E-Print Network [OSTI]

    F. Arqueros; F. Blanco; D. Garcia-Pinto; M. Ortiz; J. Rosado

    2008-07-30T23:59:59.000Z

    Detection of the air-fluorescence radiation induced by the charged particles of extensive air showers is a well-established technique for the study of ultra-high energy cosmic rays. Fluorescence telescopes provide a nearly calorimetric measure of the primary energy. Presently the main source of systematic uncertainties comes from our limited accuracy in the fluorescence yield, that is, the number of fluorescence photons emitted per unit of energy deposited in the atmosphere by the shower particles. In this paper the current status of our knowledge on the fluorescence yield both experimental an theoretical will be discussed.

  1. Magnetic fluorescent lamp

    DOE Patents [OSTI]

    Berman, S.M.; Richardson R.W.

    1983-12-29T23:59:59.000Z

    The radiant emission of a mercury-argon discharge in a fluorescent lamp assembly is enhanced by providing means for establishing a magnetic field with lines of force along the path of electron flow through the bulb of the lamp assembly, to provide Zeeman splitting of the ultraviolet spectral line. Optimum results are obtained when the magnetic field strength causes a Zeeman splitting of approximately 1.7 times the thermal line width.

  2. STORM/PALM - Super Resolution Fluorescence Microscope | EMSL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    STORMPALM - Super Resolution Fluorescence Microscope STORMPALM - Super Resolution Fluorescence Microscope EMSL has developed and offers Fluorescence, Super Resolution STORM...

  3. Fluorescence analyzer for lignin

    SciTech Connect (OSTI)

    Berthold, John W. (Salem, OH); Malito, Michael L. (Hubbard, OH); Jeffers, Larry (Alliance, OH)

    1993-01-01T23:59:59.000Z

    A method and apparatus for measuring lignin concentration in a sample of wood pulp or black liquor comprises a light emitting arrangement for emitting an excitation light through optical fiber bundles into a probe which has an undiluted sensing end facing the sample. The excitation light causes the lignin concentration to produce fluorescent emission light which is then conveyed through the probe to analyzing equipment which measures the intensity of the emission light. Measures a This invention was made with Government support under Contract Number DOE: DE-FC05-90CE40905 awarded by the Department of Energy (DOE). The Government has certain rights in this invention.

  4. Fluorescent temperature sensor

    DOE Patents [OSTI]

    Baker, Gary A [Los Alamos, NM; Baker, Sheila N [Los Alamos, NM; McCleskey, T Mark [Los Alamos, NM

    2009-03-03T23:59:59.000Z

    The present invention is a fluorescent temperature sensor or optical thermometer. The sensor includes a solution of 1,3-bis(1-pyrenyl)propane within a 1-butyl-1-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ionic liquid solvent. The 1,3-bis(1-pyrenyl)propane remains unassociated when in the ground state while in solution. When subjected to UV light, an excited state is produced that exists in equilibrium with an excimer. The position of the equilibrium between the two excited states is temperature dependent.

  5. Identification of Nucleotides with Identical Fluorescent Labels Based on Fluorescence

    E-Print Network [OSTI]

    Myrick, Michael Lenn

    Identification of Nucleotides with Identical Fluorescent Labels Based on Fluorescence Polarization for discriminating among the four DNA nucleotides la- beled identically with tetramethylrhodamine is described and demonstrated. Labeled nucleotides were dissolved in buffered surfactant solutions. In room temperature 4.5 m

  6. Nuclear Resonance Fluorescence for Materials Assay

    E-Print Network [OSTI]

    Quiter, Brian

    2010-01-01T23:59:59.000Z

    clandestine material with nuclear resonance fluorescence”.E. Norman, UC Berkeley Dept. of Nuclear Engineering, privatepp. 349. G. Warren et al. “Nuclear Resonance Fluorescence of

  7. Fluorescent fluid interface position sensor

    DOE Patents [OSTI]

    Weiss, Jonathan D.

    2004-02-17T23:59:59.000Z

    A new fluid interface position sensor has been developed, which is capable of optically determining the location of an interface between an upper fluid and a lower fluid, the upper fluid having a larger refractive index than a lower fluid. The sensor functions by measurement, of fluorescence excited by an optical pump beam which is confined within a fluorescent waveguide where that waveguide is in optical contact with the lower fluid, but escapes from the fluorescent waveguide where that waveguide is in optical contact with the upper fluid.

  8. Nuclear Resonance Fluorescence for Nuclear Materials Assay

    E-Print Network [OSTI]

    Quiter, Brian Joseph

    2010-01-01T23:59:59.000Z

    Potential of Nuclear Resonance Fluorescence . . . . . . . .2.9.1 Nuclear ThomsonSections . . . . . . . . . . . . . . . Nuclear Resonance

  9. GREEN FLUORESCENT PROTEIN The green revolution

    E-Print Network [OSTI]

    Stearns, Tim

    GREEN FLUORESCENT PROTEIN The green revolution Green fluorescent protein allows gene expression a fluorescent product when expressed. Just such a molecule, green fluorescent protein (GFP), has recently green light when disturbed (often seen when riding in a boat at night). In Aequorea, the green

  10. Fluorescence of molecular excimers

    SciTech Connect (OSTI)

    Nurmukhametov, R.N.; Sakhno, T.V.; Saukov, G.G.; Khakhel, O.A. [L. Ya. Karpov Research Physiochemical Institute, Moscow (Russian Federation)

    1995-11-01T23:59:59.000Z

    The phenomena of excimer fluorescence are most thoroughly studied in solutions of polycyclic aromatic hydrocarbons (PAHs). Therefore, excimer formation is usually treated with reference to molecules of this class of compounds. In the literature, only a qualitative picture of the energetics of excimer formation is given. It is assumed that dimerization of electron-excited and unexcited molecules is followed by the splitting of molecular electron-excited levels. PAH molecules are characterized by two lower excited levels: {sup 1}L{sub a} and {sup 1}L{sub b} (according to Platt`s classification). The S{sub 1}* state of some PAH compounds (e.g., naphthalene, phenanthrene, pyrene) is {sup 1}L{sub b}, while in other PAH (anthracene, naphthacene, perylene, etc.) it is the {sup 1}L{sub a} state. It is assumed that the {sup 1}L{sub a}-level is split more significantly than the {sup 1}L{sub b} level. Therefore, for all PAH investigated the excimer state is described as a lower-lying component of the split {sup 1}L{sub a} level. Quantum-chemical consideration of the splitting of electron levels of PAH molecules in excimers is undertaken. Unfortunately, in this case the description is also of a qualitative character. In the cited work, a correlation is noted between the energy of the {sup 1}L{sub a} state of the molecule and the wave number corresponding to the maximum of the emission band of the excimer. However, it does not give the wavelength of the maximum of the excimer band for some PAH, in other words, a definite dependence of the position of this band on molecular structure. The present work is devoted to a search for an answer to this question.

  11. A spreadsheet for analyzing the in situ performance of fluorescent luminaires

    SciTech Connect (OSTI)

    Rubinstein, F.; Zhang, Chin.

    1991-08-01T23:59:59.000Z

    A spreadsheet program for determining system efficacy, power input and light output of common 4 ft fluorescent lighting systems under realistic operating conditions is described. The program uses accepted IES engineering principles to precisely account for ballast factor, existing thermal conditions and maintenance practices. The spreadsheet, which includes a data base of lamp and ballast performance data, can be used to calculate the cost-effectiveness of many common lighting retrofits.

  12. LED Record Efficacy and Brightness

    Broader source: Energy.gov [DOE]

    Designed for general lighting applications such as street, industrial, and parking garage lighting, the Cree XLamp® power LED sets new records for LED brightness and efficacy, up to 85 lm/W at 350 mA. The XLamp utilizes Cree's performance breakthrough EZBright™ LED chip; both products include technology that was developed in part with R&D funding support from DOE.

  13. Luminous Efficacy Standards for General Purpose Lights

    Broader source: Energy.gov [DOE]

    Assembly Bill 178, adopted in June 2007, established efficacy* standards for general purpose lights sold in the state of Nevada. The bill set the required efficacy at 25 lumens per watt (lm/W) of...

  14. Covered Product Category: Fluorescent Ballasts

    Broader source: Energy.gov [DOE]

    FEMP provides acquisition guidance and federal efficiency requirements across a variety of product categories, including fluorescent ballasts, which is a FEMP designated product category. Federal laws and requirements mandate that agencies meet these efficiency requirements in all procurement and acquisition actions that are not specifically exempted by law.

  15. Covered Product Category: Fluorescent Luminaires

    Broader source: Energy.gov [DOE]

    FEMP provides acquisition guidance and Federal efficiency requirements across a variety of product categories, including fluorescent luminaires. Federal laws and requirements mandate that agencies meet these efficiency requirements in all procurement and acquisition actions that are not specifically exempted by law.

  16. Fluorescent Magnetic Nanoparticles for Biomedical Applications

    E-Print Network [OSTI]

    Candea, George

    Fluorescent Magnetic Nanoparticles for Biomedical Applications V.M.Dao, Dr. G. Coullerez, Dr. L, the main goal was to synthesize and to characterize novel fluorescent magnetic nanoparticles. These nanoparticles (NPs) involve superparamagnetic iron oxide nanoparticles (SPIONs), a fluorescently-labeled polymer

  17. A cryogenic fluorescence spectroscopic study of uranyl carbonate...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    fluorescence spectroscopic study of uranyl carbonate, phosphate, and oxyhydroxide minerals. A cryogenic fluorescence spectroscopic study of uranyl carbonate, phosphate, and...

  18. Fluorescence based chemical sensors for corrosion detection

    SciTech Connect (OSTI)

    Johnson, R.E. [LeTourneau Univ., Longview, TX (United States). Dept. of Chemistry; Agarwala, V.S. [Naval Air Warfare Center Aircraft Div., Patuxent River, MD (United States)

    1997-12-01T23:59:59.000Z

    Several fluorescent materials have been identified as possible corrosion sensing coatings. These are either redox or metal ion complex materials. The redox materials are nonfluorescent in the reduced state and become fluorescent upon oxidation. Incorporated into paint coatings, they provide an early warning of corrosive conditions at the metal or alloy surface. The metal ion complex materials only fluoresce when the organic compound complexes with metal ions such as those generated in corrosion reactions. Fluorescent materials have been incorporated into paint coatings and on metal surfaces for the detection of corrosion. Oxine reacts with aluminum oxide on corroded aluminum to give a fluorescence that can be photographed in UV light. Several other materials were found to have good fluorescence but cannot be reversibly oxidized or reduced at the present time. More work will be done with these compounds as well as with Schiff bases to develop new fluorescent chemical sensing materials for smart coating on alloy surfaces.

  19. Fluorescent optical liquid level sensor

    DOE Patents [OSTI]

    Weiss, Jonathan D. (Albuquerque, NM)

    2001-01-01T23:59:59.000Z

    A liquid level sensor comprising a transparent waveguide containing fluorescent material that is excited by light of a first wavelength and emits at a second, longer wavelength. The upper end of the waveguide is connected to a light source at the first wavelength through a beveled portion of the waveguide such that the input light is totally internally reflected within the waveguide above an air/liquid interface in a tank but is transmitted into the liquid below this interface. Light is emitted from the fluorescent material only in those portions of the waveguide that are above the air/liquid interface, to be collected at the upper end of the waveguide by a detector that is sensitive only to the second wavelength. As the interface moves down in the tank, the signal strength from the detector will increase.

  20. Fluorescent Nanoparticles for Radiation DetectionFluorescent Nanoparticles

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8,Dist.New MexicoFinancingProofWorking OutsideFluorescent Lightingfor

  1. Saccharide sensing molecules having enhanced fluorescent properties

    DOE Patents [OSTI]

    Satcher Jr., Joe H.; Lane, Stephen M.; Darrow, Christopher B.; Cary, Douglas R.; Tran, Joe Anh

    2004-01-06T23:59:59.000Z

    The present invention provides formulae for fluorescent compounds that have a number of properties which make them uniquely suited for use in sensors of analytes such as saccharides. The advantageous fluorescent properties include favorable excitation wavelengths, emission wavelengths, fluorescence lifetimes, and photostability. Additional advantageous properties include enhanced aqueous solubility, as well as temperature and pH sensitivity. The compound comprises an aryl or a substituted phenyl botonic acid that acts as a substrate recognition component, a fluorescence switch component, and a fluorophore. Fluorescent compounds are described that are excited at wavelengths greater than 400 nm and emit at wavelengths greater than 450 nm, which is advantageous for optical transmission through skin. The fluorophore is typically selected from transition metal-ligand complexes and thiazine, oxazine, oxazone, or oxazine-one as well as anthracene compounds. The fluorescent compound can be immobilized in a glucose permeable biocompatible polymer matrix that is implantable below the skin.

  2. Scanning fluorescent microthermal imaging apparatus and method

    DOE Patents [OSTI]

    Barton, Daniel L. (Albuquerque, NM); Tangyunyong, Paiboon (Albuquerque, NM)

    1998-01-01T23:59:59.000Z

    A scanning fluorescent microthermal imaging (FMI) apparatus and method is disclosed, useful for integrated circuit (IC) failure analysis, that uses a scanned and focused beam from a laser to excite a thin fluorescent film disposed over the surface of the IC. By collecting fluorescent radiation from the film, and performing point-by-point data collection with a single-point photodetector, a thermal map of the IC is formed to measure any localized heating associated with defects in the IC.

  3. Scanning fluorescent microthermal imaging apparatus and method

    DOE Patents [OSTI]

    Barton, D.L.; Tangyunyong, P.

    1998-01-06T23:59:59.000Z

    A scanning fluorescent microthermal imaging (FMI) apparatus and method is disclosed, useful for integrated circuit (IC) failure analysis, that uses a scanned and focused beam from a laser to excite a thin fluorescent film disposed over the surface of the IC. By collecting fluorescent radiation from the film, and performing point-by-point data collection with a single-point photodetector, a thermal map of the IC is formed to measure any localized heating associated with defects in the IC. 1 fig.

  4. Laser-Stimulated Fluorescence in Paleontology

    E-Print Network [OSTI]

    Kaye, Thomas G.; Falk, Amanda Renee; Pittman, Michael; Sereno, Paul C.; Martin, Larry D.; Burnham, David A.; Gong, Enpu; Xu, Xing; Wang, Yinan

    2015-05-27T23:59:59.000Z

    . doi: 10.1371/journal.pone. 0009223 PMID: 20169153 8. Warren TS, Gleason S, Bostwick RC, Verbeek ER. Ultraviolet light and fluorescent minerals: under- standing, collecting and displaying fluorescent minerals. GemGuides Book. 1999. 9. Hibbs AR. Confocal... fake and genuine vertebrate fossils. Journal of Paleontological Techniques. 2008; 2:1–5. Laser-Stimulated Fluorescence in Paleontology PLOS ONE | DOI:10.1371/journal.pone.0125923 May 27, 2015 22 / 22 ...

  5. LED Replacements for Linear Fluorescent Lamps Webcast

    Broader source: Energy.gov [DOE]

    In this June 20, 2011 webcast on LED products marketed as replacements for linear fluorescent lamps, Jason Tuenge of the Pacific Northwest National Laboratory (PNNL) discussed current Lighting...

  6. Portable spotter for fluorescent contaminants on surfaces

    DOE Patents [OSTI]

    Schuresko, Daniel D. (Oak Ridge, TN)

    1980-01-01T23:59:59.000Z

    A portable fluorescence-based spotter for polynuclear aromatic hydrocarbon contamination on personnel and work area surfaces under ambient lighting conditions is provided. This instrument employs beam modulation and phase sensitive detection for discriminating between fluorescence from organic materials from reflected background light and inorganic fluorescent material. The device uses excitation and emission filters to provide differentiation between classes of aromatic organic compounds. Certain inorganic fluorescent materials, including heavy metal compounds, may also be distinguished from the organic compounds, despite both having similar optical properties.

  7. Covered Product Category: Compact Fluorescent Lamps

    Broader source: Energy.gov [DOE]

    FEMP provides acquisition guidance across a variety of product categories, including compact fluorescent lamps (CFLs), which are an ENERGY STAR-qualified product category.

  8. FAA Fluorescent Penetrant Laboratory Inspections

    SciTech Connect (OSTI)

    WINDES,CONNOR L.; MOORE,DAVID G.

    2000-08-02T23:59:59.000Z

    The Federal Aviation Administration Airworthiness Assurance NDI Validation Center currently assesses the capability of various non-destructive inspection (NDI) methods used for analyzing aircraft components. The focus of one such exercise is to evaluate the sensitivity of fluorescent liquid penetrant inspection. A baseline procedure using the water-washable fluorescent penetrant method defines a foundation for comparing the brightness of low cycle fatigue cracks in titanium test panels. The analysis of deviations in the baseline procedure will determine an acceptable range of operation for the steps in the inspection process. The data also gives insight into the depth of each crack and which step(s) of the inspection process most affect penetrant sensitivities. A set of six low cycle fatigue cracks produced in 6.35-mm thick Ti-6Al-4V specimens was used to conduct the experiments to produce sensitivity data. The results will document the consistency of the crack readings and compare previous experiments to find the best parameters for water-washable penetrant.

  9. SSL Pricing and Efficacy Trend Analysis for Utility Program Planning...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Market-Based Programs Technical Information Network SSL Pricing and Efficacy Trend Analysis for Utility Program Planning SSL Pricing and Efficacy Trend Analysis for Utility...

  10. A novel fluorescence detection method for organosilanes

    SciTech Connect (OSTI)

    Yang, H.X.; Craw, M.T.; Depew, M.C.; Wan, J.K.S. (Queen's Univ., Kingston, Ontario (Canada))

    1989-02-01T23:59:59.000Z

    Quinones such as phenanthraquinone and anthraquinone react with organosilanes giving persistent, strongly fluorescent radicals. The reactions are photochemically initiated, rapid, and facile; detection of concentrations of silanes in the 10{sup {minus}7} M range are readily achieved. The staring materials do not fluorescence making the procedure simple, selective and specific.

  11. Applications of Nuclear Resonance Fluorescence

    SciTech Connect (OSTI)

    Warren, Glen A.; Detwiler, Rebecca S.; Peplowski, Patrick N.

    2010-11-11T23:59:59.000Z

    Nuclear Resonance Fluorescence (NRF) has the potential of addressing a wide variety of applications, which require isotopic and/or elemental information about a sample. We have investigated a variety of non-proliferation applications that may be addressed by NRF. From these applications, we have selected two, measuring uranium enrichment in UF6 cylinders and material verification in dismantlement, to investigate in more detail. Analytical models have been developed to evaluate these applications, and test measurements have been conducted to validate those models. We found that it is unlikely with current technology to address the requirements for UF6 cylinder enrichment measurements. In contrast, NRF is a very promising approach for material verification for dismantlement.

  12. Hard X-ray Fluorescence Measurements of Heteroepitaxial Solid...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Hard X-ray Fluorescence Measurements of Heteroepitaxial Solid Oxide Fuel Cell Cathode Materials. Hard X-ray Fluorescence Measurements of Heteroepitaxial Solid Oxide Fuel Cell...

  13. Using Nuclear Resonance Fluorescence for Nondestructive Isotopic Analysis

    E-Print Network [OSTI]

    Ludewigt, Bernhard A.

    2010-01-01T23:59:59.000Z

    7, (1959) pp. 54. [12] B.J. Quiter, ``Nuclear ResonanceFluorescence for Nuclear Materials Assay,'' University ofclandestine material with nuclear resonance fluorescence,"

  14. Super-Resolution Fluorescence Nanoscopy Applied to Image Core...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Super-Resolution Fluorescence Nanoscopy Applied to Image Core-Shell Photoswitching Nanoparticles and their Self-Assemblies . Super-Resolution Fluorescence Nanoscopy Applied to...

  15. Performance of T12 and T8 Fluorescent Lamps and Troffers and LED Linear Replacement Lamps CALiPER Benchmark Report

    SciTech Connect (OSTI)

    Myer, Michael; Paget, Maria L.; Lingard, Robert D.

    2009-01-16T23:59:59.000Z

    The Department of Energy (DOE) Commercially Available LED Product Evaluation and Reporting (CALiPER) Program was established in 2006 to investigate the performance of light-emitting diode (LED) based luminaires and replacement lamps. To help users better compare LED products with conventional lighting technologies, CALiPER has also performed benchmark research and testing of traditional (i.e., non-LED) lamps and fixtures. This benchmark report addresses standard 4-foot fluorescent lamps (i.e., T12 and T8) and the 2-foot by 4-foot recessed troffers in which they are commonly used. This report also examines available LED replacements for T12 and T8 fluorescent lamps, and their application in fluorescent troffers. The construction and operation of linear fluorescent lamps and troffers are discussed, as well as fluorescent lamp and fixture performance, based on manufacturer data and CALiPER benchmark testing. In addition, the report describes LED replacements for linear fluorescent lamps, and compares their bare lamp and in situ performance with fluorescent benchmarks on a range of standard lighting measures, including power usage, light output and distribution, efficacy, correlated color temperature, and the color rendering index. Potential performance and application issues indicated by CALiPER testing results are also examined.

  16. Glucose sensing molecules having selected fluorescent properties

    DOE Patents [OSTI]

    Satcher, Jr., Joe H.; Lane, Stephen M.; Darrow, Christopher B.; Cary, Douglas R.; Tran, Joe Anh

    2004-01-27T23:59:59.000Z

    An analyte sensing fluorescent molecule that employs intramolecular electron transfer is designed to exhibit selected fluorescent properties in the presence of analytes such as saccharides. The selected fluorescent properties include excitation wavelength, emission wavelength, fluorescence lifetime, quantum yield, photostability, solubility, and temperature or pH sensitivity. The compound comprises an aryl or a substituted phenyl boronic acid that acts as a substrate recognition component, a fluorescence switch component, and a fluorophore. The fluorophore and switch component are selected such that the value of the free energy for electron transfer is less than about 3.0 kcal mol.sup.-1. Fluorescent compounds are described that are excited at wavelengths greater than 400 nm and emit at wavelengths greater than 450 nm, which is advantageous for optical transmission through skin. The fluorophore is typically selected from transition metal-ligand complexes and thiazine, oxazine, oxazone, or oxazine-one as well as anthracene compounds. The fluorescent compound can be immobilized in a glucose permeable biocompatible polymer matrix that is implantable below the skin.

  17. Hiding patterns with daylight fluorescent inks

    E-Print Network [OSTI]

    Romain Rossier; Roger D. Hersch; School Of Computer; Communication Sciences; Ecole Polytechnique; Fédérale Lausanne

    We propose a method for hiding patterns within printed images by making use of classical and of two daylight fluorescent magenta and yellow inks. Under the D65 illuminant we establish in the CIELAB space the gamut of a classical cmyk printer and the gamut of the same printer using a combination of classical inks with daylight fluorescent inks. These gamuts show that a significant part of the classical ink gamut can be reproduced by combining classical inks with daylight fluorescent inks. By printing parts of images with a combination of classical and daylight fluorescent inks instead of using classical inks only, we can hide security patterns within printed images. Under normal daylight, we do not see any difference between the parts printed with classical inks only and the parts printed with daylight fluorescent inks and classical inks. By changing the illumination, e.g. by viewing the printed image under a tungsten lamp or under a UV lamp, the daylight fluorescent inks change their colors and reveal the security pattern formed by combinations of classical inks and of daylight fluorescent inks.

  18. Photosystem II fluorescence lifetime imaging in avocado leaves: Contributions of the lutein-epoxide and violaxanthin cycles to fluorescence quenching

    E-Print Network [OSTI]

    Govindjee

    Photosystem II fluorescence lifetime imaging in avocado leaves: Contributions of the lutein a fluorescence were made on leaves of avocado plants to study whether rapidly reversible Dp

  19. Probing the denatured state ensemble with fluorescence

    E-Print Network [OSTI]

    Alston, Roy Willis

    2004-09-30T23:59:59.000Z

    around the original tryptophan substitutions in RNase Sa. Regardless of the denaturant, ?max for the proteins and model compounds differed very little, 349.3 ± 1.2 nm. However, significant differences were observed in the fluorescence intensity at ?max...

  20. Fluorescence Imaging for Nuclear Arms Control Verification

    E-Print Network [OSTI]

    Feener, Jessica S

    2014-08-14T23:59:59.000Z

    treaties. Specifically, this technique uses fluorescence imaging to determine fissile material attributes in verifying, during the dismantlement process, an uncanned nuclear warhead or warhead component without revealing sensitive information. This could...

  1. Fluorescence-based optical glucose sensing 

    E-Print Network [OSTI]

    Meledeo, Michael Adam

    2002-01-01T23:59:59.000Z

    Previous studies have indicated that optical means of blood glucose detection are feasible and provide a minimally invasive alternative to current commercially available modalities. Fluorescence spectroscopy has shown promise in many examples...

  2. Using Nuclear Resonance Fluorescence for Nondestructive Isotopic Analysis

    E-Print Network [OSTI]

    Ludewigt, Bernhard A.

    2010-01-01T23:59:59.000Z

    spent fuel assay using Nuclear Resonance Fluorescence,” Annual Meeting of the Institute of Nuclear Materials Management,

  3. Multiplexed fluorescence detector system for capillary electrophoresis

    DOE Patents [OSTI]

    Yeung, E.S.; Taylor, J.A.

    1994-06-28T23:59:59.000Z

    A fluorescence detection system for capillary electrophoresis is provided wherein the detection system can simultaneously excite fluorescence and substantially simultaneously monitor separations in multiple capillaries. This multiplexing approach involves laser irradiation of a sample in a plurality of capillaries through optical fibers that are coupled individually with the capillaries. The array is imaged orthogonally through a microscope onto a charge-coupled device camera for signal analysis. 14 figures.

  4. Multiplexed fluorescence detector system for capillary electrophoresis

    DOE Patents [OSTI]

    Yeung, E.S.; Taylor, J.A.

    1996-03-12T23:59:59.000Z

    A fluorescence detection system for capillary electrophoresis is provided wherein the detection system can simultaneously excite fluorescence and substantially simultaneously monitor separations in multiple capillaries. This multiplexing approach involves laser irradiation of a sample in a plurality of capillaries through optical fibers that are coupled individually with the capillaries. The array is imaged orthogonally through a microscope onto a charge-coupled device camera for signal analysis. 14 figs.

  5. Ultratrace analysis of transuranic actinides by laser-induced fluorescence

    DOE Patents [OSTI]

    Miller, S.M.

    1983-10-31T23:59:59.000Z

    Ultratrace quantities of transuranic actinides are detected indirectly by their effect on the fluorescent emissions of a preselected fluorescent species. Transuranic actinides in a sample are coprecipitated with a host lattice material containing at least one preselected fluorescent species. The actinide either quenches or enhances the laser-induced fluorescence of the preselected fluorescent species. The degree of enhancement or quenching is quantitatively related to the concentration of actinide in the sample.

  6. Supercontinuum Stimulated Emission Depletion Fluorescence Lifetime Imaging

    SciTech Connect (OSTI)

    Lesoine, Michael; Bose, Sayantan; Petrich, Jacob; Smith, Emily

    2012-06-13T23:59:59.000Z

    Supercontinuum (SC) stimulated emission depletion (STED) fluorescence lifetime imaging is demonstrated by using time-correlated single-photon counting (TCSPC) detection. The spatial resolution of the developed STED instrument was measured by imaging monodispersed 40-nm fluorescent beads and then determining their fwhm, and was 36 ± 9 and 40 ± 10 nm in the X and Y coordinates, respectively. The same beads measured by confocal microscopy were 450 ± 50 and 430 ± 30 nm, which is larger than the diffraction limit of light due to underfilling the microscope objective. Underfilling the objective and time gating the signal were necessary to achieve the stated STED spatial resolution. The same fluorescence lifetime (2.0 ± 0.1 ns) was measured for the fluorescent beads by using confocal or STED lifetime imaging. The instrument has been applied to study Alexa Fluor 594-phalloidin labeled F-actin-rich projections with dimensions smaller than the diffraction limit of light in cultured cells. Fluorescence lifetimes of the actin-rich projections range from 2.2 to 2.9 ns as measured by STED lifetime imaging.

  7. Fluorescence energy transfer enhancement in aluminum nanoapertures

    E-Print Network [OSTI]

    de Torres, Juan; Moparthi, Satish Babu; Grigoriev, Victor; Wenger, Jérome

    2015-01-01T23:59:59.000Z

    Zero-mode waveguides (ZMWs) are confining light into attoliter volumes, enabling single molecule fluorescence experiments at physiological micromolar concentrations. Among the fluorescence spectroscopy techniques that can be enhanced by ZMWs, F\\"{o}rster resonance energy transfer (FRET) is one of the most widely used in life sciences. Combining zero-mode waveguides with FRET provides new opportunities to investigate biochemical structures or follow interaction dynamics at micromolar concentration with single molecule resolution. However, prior to any quantitative FRET analysis on biological samples, it is crucial to establish first the influence of the ZMW on the FRET process. Here, we quantify the FRET rates and efficiencies between individual donor-acceptor fluorophore pairs diffusing in aluminum zero-mode waveguides. Aluminum ZMWs are important structures thanks to their commercial availability and the large literature describing their use for single molecule fluorescence spectroscopy. We also compare the ...

  8. Ultrabright fluorescent OLEDS using triplet sinks

    DOE Patents [OSTI]

    Zhang, Yifan; Forrest, Stephen R; Thompson, Mark

    2013-06-04T23:59:59.000Z

    A first device is provided. The first device further comprises an organic light emitting device. The organic light emitting device further comprises an anode, a cathode, and an emissive layer disposed between the anode and the cathode. The emissive layer further comprises an organic host compound, an organic emitting compound capable of fluorescent emission at room temperature, and an organic dopant compound. The triplet energy of the dopant compound is lower than the triplet energy of the host compound. The dopant compound does not strongly absorb the fluorescent emission of the emitting compound.

  9. Design, Syntheses and Applications of Fluorescent Dyes

    E-Print Network [OSTI]

    Wu, Liangxing

    2010-10-12T23:59:59.000Z

    .11. Normalized UV absorbance and fluorescence of 1h and the labeled streptavidin 1s in 0.1 M lithium phosphate buffer, pH 7.4 ..................... 54 3.1. Spectra of BODIPYs 9 in CH 2 Cl 2 ........................................................... 65...) ............................................................ 94 4.8. Dependence of electronic spectra of 15h on pH ..................................... 96 4.9. UV-Vis absorption and fluorescence spectra of rosamine 25 and 25 labeled avidin in 0.1 M phosphate buffer, pH 7...

  10. Compact Fluorescent Plug-In Ballast-in-a-Socket

    SciTech Connect (OSTI)

    Rebecca Voelker

    2001-12-21T23:59:59.000Z

    The primary goal of this program was to develop a ballast system for plug-in CFLs (compact fluorescent lamps) that will directly replace standard metal shell, medium base incandescent lampholders (such as Levition No. 6098) for use with portable lamp fixtures, such as floor, table and desk lamps. A secondary goal was to identify a plug-in CFL that is optimized for use with this ballast. This Plug-in CFL Ballastin-a-Socket system will allow fixture manufacturers to easily manufacture CFL-based high-efficacy portable fixtures that provide residential and commercial consumers with attractive, cost-effective, and energy-efficient fixtures for use wherever portable incandescent fixtures are used today. The advantages of this proposed system over existing CFL solutions are that the fixtures can only be used with high-efficacy CFLs, and they will be more attractive and will have lower life-cycle costs than screw-in or adapter-based CFL retrofit solutions. These features should greatly increase the penetration of CFL's into the North American market. Our work has shown that using integrated circuits it is quite feasible to produce a lamp-fixture ballast of a size comparable to the current Edison-screw 3-way incandescent fixtures. As for price points for BIAS-based fixtures, end-users polled by the Lighting Research Institute at RPI indicated that they would pay as much as an additional $10 for a lamp containing such a ballast. The ballast has been optimized to run with a 26 W amalgam triple biax lamp in the base-down position, yet can accept non-amalgam versions of the lamp. With a few part alterations, the ballast can be produced to support 32 W lamps as well. The ballast uses GE's existing L-Comp[1] power topology in the circuit so that the integrated circuit design would be a design that could possibly be used by other CFL and EFL products with minor modifications. This gives added value by reducing cost and size of not only the BIAS, but also possibly other integral CFL and future dimmable integral and plug-in versions of the EFL products.

  11. CODED SPECTROSCOPY FOR ETHANOL DETECTION IN DIFFUSE, FLUORESCENT MEDIA

    E-Print Network [OSTI]

    ABSTRACT CODED SPECTROSCOPY FOR ETHANOL DETECTION IN DIFFUSE, FLUORESCENT MEDIA by Scott Thomas Mc FOR ETHANOL DETECTION IN DIFFUSE, FLUORESCENT MEDIA by Scott Thomas McCain Department of Electrical

  12. Modelling of a Fluorescent Lamp Plasma

    E-Print Network [OSTI]

    Eindhoven, Technische Universiteit

    Technische Universiteit Eindhoven, op gezag van de Rector Magnificus, prof.dr. R.A. van Santen, voor een TECHNISCHE UNIVERSITEIT EINDHOVEN Hartgers, Albertus Modelling of a Fluorescent Lamp Plasma / by Albertus Hartgers. - Eindhoven : Technische Universiteit Eindhoven, 2003. - Proefschrift. ISBN 90-386-1665-1 NUR 924

  13. Oil Classification with Fluorescence Spectroscopy Engineering Physics

    E-Print Network [OSTI]

    Oldenburg, Carl von Ossietzky Universität

    detected by these channels. The investigation used three methods to examine crude oil, heavy oil, sludge1 Oil Classification with Fluorescence Spectroscopy Engineering Physics Master of Engineering and classification of oil spills on water surfaces. It is an overview of the laser remote sensor technique

  14. DNA sequencing using fluorescence background electroblotting membrane

    DOE Patents [OSTI]

    Caldwell, Karin D. (Salt Lake City, UT); Chu, Tun-Jen (Salt Lake City, UT); Pitt, William G. (Orem, UT)

    1992-01-01T23:59:59.000Z

    A method for the multiplex sequencing on DNA is disclosed which comprises the electroblotting or specific base terminated DNA fragments, which have been resolved by gel electrophoresis, onto the surface of a neutral non-aromatic polymeric microporous membrane exhibiting low background fluorescence which has been surface modified to contain amino groups. Polypropylene membranes are preferably and the introduction of amino groups is accomplished by subjecting the membrane to radio or microwave frequency plasma discharge in the presence of an aminating agent, preferably ammonia. The membrane, containing physically adsorbed DNA fragments on its surface after the electroblotting, is then treated with crosslinking means such as UV radiation or a glutaraldehyde spray to chemically bind the DNA fragments to the membrane through said smino groups contained on the surface thereof. The DNA fragments chemically bound to the membrane are subjected to hybridization probing with a tagged probe specific to the sequence of the DNA fragments. The tagging may be by either fluorophores or radioisotopes. The tagged probes hybridized to said target DNA fragments are detected and read by laser induced fluorescence detection or autoradiograms. The use of aminated low fluorescent background membranes allows the use of fluorescent detection and reading even when the available amount of DNA to be sequenced is small. The DNA bound to the membrances may be reprobed numerous times.

  15. Text-Alternative Version: LED Replacements for Linear Fluorescent Lamps

    Broader source: Energy.gov [DOE]

    Below is the text-alternative version of the "LED Replacements for Linear Fluorescent Lamps" webcast, held June 20, 2011.

  16. Confocal, FLIM & Multi-Photon Fluorescence Microscope | EMSL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    supports quantitative fluorescence resonance energy transfer (FRET) for investigating molecular interaction dynamics in living cells. The system also includes differential...

  17. Measurement and model assessment of fluorescence lifetime sensing in multiply scattering media 

    E-Print Network [OSTI]

    Kuwana, Eddy

    2005-08-29T23:59:59.000Z

    fluorescence sensor and the reliability of fluorescence lifetime measurement verify the prospect of this technology for implantable purposes....

  18. aom efficacy study: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    variations in poor localities influence the capacity for community efficacy. Through a multivariate analysis using 497 households in poor localities of Addis Ababa, we...

  19. When Crime Pays: Measuring Judicial Efficacy against Corruption in Brazil

    E-Print Network [OSTI]

    Ribeiro de Alencar, Carlos Higino; Gico, Ivo Jr.

    2010-01-01T23:59:59.000Z

    for now - crime pays in Brazil. Paginal5de27 ReferencesEfficacy against Corruption in Brazil Carlos Higino Ribeiroa widespread perception in Brazil that civil servants caught

  20. DOE Publishes Pricing and Efficacy Trend Analysis for Utility...

    Broader source: Energy.gov (indexed) [DOE]

    a new report, SSL Pricing and Efficacy Trend Analysis for Utility Program Planning. The report was created in response to requests from utilities and energy efficiency...

  1. 3,4,3-LI(1,2-HOPO): In Vitro Formation of Highly Stable Lanthanide Complexes Translates into Efficacious In Vivo Europium Decorporation

    E-Print Network [OSTI]

    Sturzbecher-Hoehne, Manuel

    2012-01-01T23:59:59.000Z

    into Efficacious In Vivo Europium Decorporation Manuelinto Efficacious In Vivo Europium Decorporation Manuelinto Efficacious In Vivo Europium Decorporation Manuel

  2. Solid state laser media driven by remote nuclear powered fluorescence

    DOE Patents [OSTI]

    Prelas, Mark A. (Columbia, MO)

    1992-01-01T23:59:59.000Z

    An apparatus is provided for driving a solid state laser by a nuclear powered fluorescence source which is located remote from the fluorescence source. A nuclear reaction produced in a reaction chamber generates fluorescence or photons. The photons are collected from the chamber into a waveguide, such as a fiber optic waveguide. The waveguide transports the photons to the remote laser for exciting the laser.

  3. Absolute Calibration of the Auger Fluorescence Detectors

    E-Print Network [OSTI]

    P. Bauleo; J. Brack; L. Garrard; J. Harton; R. Knapik; R. Meyhandan; A. C. Rovero; A. Tamashiro; D. Warner; for the Auger Collaboration

    2005-07-14T23:59:59.000Z

    Absolute calibration of the Pierre Auger Observatory fluorescence detectors uses a light source at the telescope aperture. The technique accounts for the ombined effects of all detector components in a single measurement. The calibrated 2.5 m diameter light source fills the aperture, providing uniform illumination to each pixel. The known flux from the light source and the response of the acquisition system give the required calibration for each pixel. In the lab, light source uniformity is studied using CCD images and the intensity is measured relative to NIST-calibrated photodiodes. Overall uncertainties are presently 12%, and are dominated by systematics.

  4. Fluorescent Lamp Ballasts | Department of Energy

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directed offOCHCO2: FinalOffers3.pdf0-45.pdf Flash2010-45.pdfFlash2011-43and Statement ofStrikeFluorescent

  5. Fluorescent Optical Position Sensor - Energy Innovation Portal

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8,Dist.New MexicoFinancingProofWorking OutsideFluorescent

  6. Fluorescent Pigments for High-Performance Cool Roofing and Facades...

    Energy Savers [EERE]

    dark-colored pigments for cool metal roof and faade coatings that incorporate near-infrared fluorescence and reflectance to improve energy performance. Image: PPG Industries 2...

  7. Satellite-detected fluorescence reveals global physiology of ocean phytoplankton

    E-Print Network [OSTI]

    2009-01-01T23:59:59.000Z

    2000. Jassby, A. D. and Platt, T. : Mathematical formulationTopliss, B. J. and Platt, T. : Passive fluorescence andrates (Topliss and Platt, 1986; Kiefer et al. , 1989) and

  8. atomic fluorescence spectrometry: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    S. Chapman 2010-12-08 9 Quantification of trace metals in deciduous tooth enamel using energy dispersive X-ray fluorescence spectrometry. Open Access Theses and Dissertations...

  9. Fluorescent Multiblock ?-Conjugated Polymer Nanoparticles for In Vivo Tumor Targeting

    E-Print Network [OSTI]

    Ahmed, Eilaf

    Highly fluorescent multiblock conjugated polymer nanoparticles with folic acid surface ligands are highly effective for bioimaging and in vivo tumor targeting. The targeted nanoparticles were preferentially localized in ...

  10. Time-resolved fluorescence decay measurements for flowing particles

    DOE Patents [OSTI]

    Deka, C.; Steinkamp, J.A.

    1999-06-01T23:59:59.000Z

    Time-resolved fluorescence decay measurements are disclosed for flowing particles. An apparatus and method for the measurement and analysis of fluorescence for individual cells and particles in flow are described, wherein the rapid measurement capabilities of flow cytometry and the robust measurement and analysis procedures of time-domain fluorescence lifetime spectroscopy are combined. A pulse-modulated CW laser is employed for excitation of the particles. The characteristics and the repetition rate of the excitation pulses can be readily adjusted to accommodate for fluorescence decays having a wide range of lifetimes. 12 figs.

  11. aequorea green fluorescent: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    plants. Jim Haseloff Biology and Medicine Websites Summary: light, and an accessory green fluorescent protein (GFP), which accepts energy from aequorin and reImaging green...

  12. Modeling of highly loaded fluorescent lamps

    SciTech Connect (OSTI)

    Lister, G.G.; Lawler, J.E.; Curry, J.J.

    1999-07-01T23:59:59.000Z

    Numerical modeling of the positive column of fluorescent lamps under conditions of high current density are of current interest, particularly in view of recent developments in electrodeless lamps. Current models tend to overestimate radiation output, and consequently the maintenance electric field in these discharges. Under highly loaded conditions, mercury-rare gas fluorescent lamps exhibit strong mercury depletion on axis (cataphoresis), and an understanding of resonance radiation transport under these conditions is therefore vital to the development of models with a predictive capability. The authors have explored the effect of radial cataphoresis on resonance radiation trapping for situations in which the radiation transport is dominated by foreign gas broadening, Doppler broadening, or resonance collisional broadening of the spectral line. Several different production rates per unit volume of resonance (excited) atoms have also been studied. It is advantageous in many cases to parameterize the trapped decay rate in terms of the total number of ground state atoms in the positive column independent of their radial distribution. The results of this work have been included in a numerical model of the positive column and the predicted influence on discharge parameters will be presented for cases of interest to highly loaded lamps.

  13. Development and Application of Fluorescent SDF-1 Derivatives Ryo Masuda,

    E-Print Network [OSTI]

    Takada, Shoji

    #12;1 Development and Application of Fluorescent SDF-1 Derivatives Ryo Masuda, Shinya Oishi of Medicine, 2-1 Seiryocho, Aoba-ku, Sendai 980-8575, Japan. #12;2 Abstract Background: SDF-1/CXCR4 signaling, structure-activity relationship analyses of fluorescent SDF-1 derivatives were carried out. Results: Several

  14. Improved ``Optical Highlighter'' Probes Derived from Discosoma Red Fluorescent Protein

    E-Print Network [OSTI]

    Marchant, Jonathan

    , Minneapolis, Minnesota ABSTRACT The tetrameric red fluorescent protein, DsRed, undergoes a rapid red to green-emitting species of DsRed and an enhancement of emission from the ``immature'' green species, likely caused by dequenching of fluorescence resonance energy transfer occurring within the protein tetramer. Here, we have

  15. Gregorio Weber International Prize in Biological Fluorescence 2008

    E-Print Network [OSTI]

    Weber, David J.

    Gregorio Weber International Prize in Biological Fluorescence 2008 The Gregorio Weber International Prize in Biological Fluorescence (Weber Prize) is awarded for research related to a doctoral (or finalists. Weber Prizes were awarded in 2002 and 2005. The third Weber Prize will be awarded in 2008

  16. Comparison of Segmentation Algorithms For Fluorescence Microscopy Images of Cells

    E-Print Network [OSTI]

    Bernal, Javier

    - mentation techniques are less accurate than k-means clustering with multiple clusters. Segmentation accuracy fluorescence microscopy; k-means cluster; image segmentation; cell edge; bivariate simi- larity index NUMEROUSComparison of Segmentation Algorithms For Fluorescence Microscopy Images of Cells Alden A. Dima,1

  17. Fluorescence correlation spectroscopy at high concentrations using gold bowtie nanoantennas

    E-Print Network [OSTI]

    Fan, Shanhui

    Fluorescence correlation spectroscopy at high concentrations using gold bowtie nanoantennas Anika A to extremely low concentrations. Plasmonic gold bowtie nanoantennas enhance a single molecule's fluorescence relative to a large background of unenhanced molecules, and here we show that bowties can extend FCS

  18. Teal fluorescent proteins: Characterization of a reversibly photoswitchable variant

    E-Print Network [OSTI]

    Campbell, Robert E.

    libraries of variants. mTFP1 has proven to be a particularly useful new member of the FP `toolbox green fluorescent protein (GFP) in 1961 when he was isolating aequorin, a calcium improved variants of GFP, including the variant known as enhanced green fluorescent protein (EGFP), were

  19. Application of Quantitative Fluorescence and Absorption-Edge

    E-Print Network [OSTI]

    Sparks, Donald L.

    Application of Quantitative Fluorescence and Absorption-Edge Computed Microtomography to Image, Chicago, Illinois 60637 This paper shows that synchrotron-based fluorescence and absorption-edge computed, which had a well-correlated metal coating. Absorption-edge CMT showed the three-dimensional distribution

  20. SIMULTANEOUS MEASUREMENT OF CIRCULAR DICHROISM AND FLUORESCENCE POLARIZATION ANISOTROPY.

    SciTech Connect (OSTI)

    SUTHERLAND,J.C.

    2002-01-19T23:59:59.000Z

    Circular dichroism and fluorescence polarization anisotropy are important tools for characterizing biomolecular systems. Both are used extensively in kinetic experiments involving stopped- or continuous flow systems as well as titrations and steady-state spectroscopy. This paper presents the theory for determining circular dichroism and fluorescence polarization anisotropy simultaneously, thus insuring the two parameters are recorded under exactly the same conditions and at exactly the same time in kinetic experiments. The approach to measuring circular dichroism is that used in almost all conventional dichrographs. Two arrangements for measuring fluorescence polarization anisotropy are described. One uses a single fluorescence detector and signal processing with a lock-in amplifier that is similar to the measurement of circular dichroism. The second approach uses classic ''T'' format detection optics, and thus can be used with conventional photon-counting detection electronics. Simple extensions permit the simultaneous measurement of the absorption and excitation intensity corrected fluorescence intensity.

  1. Radioiodine detector based on laser induced fluorescence

    DOE Patents [OSTI]

    McDonald, Jimmie R. (Upper Marlboro, MD); Baronavski, Andrew P. (Alexandria, VA)

    1980-01-01T23:59:59.000Z

    The invention involves the measurement of the concentration of the radioisotope .sup.129 I.sub.2 in the presence of a gas. The invention uses a laser to excite a sample of the .sup.129 I.sub.2 in a sample gas chamber and a reference sample of a known concentration of .sup.129 I.sub.2 in a reference gas chamber. The .sup.129 I.sub.2 in the sample and reference gas chamber each gives off fluorescence emissions which are received by photomultipliers which provide signals to a detector. The detector uses a ratioing technique to determine the concentration of .sup.129 I.sub.2 in the sample gas chamber.

  2. Fluorescence in nonlocal dissipative periodic structures

    E-Print Network [OSTI]

    Francesco Intravaia; Kurt Busch

    2015-02-24T23:59:59.000Z

    We present an approach for the description of fluorescence from optically active material embedded in layered periodic structures. Based on an exact electromagnetic Green's tensor analysis, we determine the radiative properties of emitters such as the local photonic density of states, Lamb shifts, line widths etc. for a finite or infinite sequence of thin alternating plasmonic and dielectric layers. In the effective medium limit, these systems may exhibit hyperbolic dispersion relations so that the large wave-vector characteristics of all constituents and processes become relevant. These include the finite thickness of the layers, the nonlocal properties of the constituent metals, and local-field corrections associated with an emitter's dielectric environment. In particular, we show that the corresponding effects are non-additive and lead to considerable modifications of an emitter's luminescence properties.

  3. Mercury Lamps Recycling Fluorescent light-tubes, compact fluorescent bulbs, mercury and sodium vapor lamps, ultraviolet and

    E-Print Network [OSTI]

    Baker, Chris I.

    Mercury Lamps Recycling Fluorescent light-tubes, compact fluorescent bulbs, mercury and sodium labeled for shipment to a recycling plant for mercury, glass and aluminum recovery. The beneficial re can be recycled infinitely without losing its purity or strength. While the primary end product

  4. X-Ray Fluorescence (XRF) Analysis of Obsidian Artifacts from Shoofly Ruin, Central Arizona

    E-Print Network [OSTI]

    Shackley, M. Steven

    1986-01-01T23:59:59.000Z

    X-RAY FLUORESCENCE (XRF) ANALYSIS OF OBSIDIAN ARTIFACTS FROM62:426-437. SOUTHWEST XRF PAPER Table 1. X-ray fluorescence

  5. Air Fluorescence Relevant for Cosmic-Ray Detection - Summary of the 5th Fluorescence Workshop, El Escorial 2007

    E-Print Network [OSTI]

    Fernando Arqueros; Joerg R. Hoerandel; Bianca Keilhauer

    2008-07-24T23:59:59.000Z

    High-energy cosmic rays with energies exceeding $10^{17}$ eV are frequently observed by measurements of the fluorescence light induced by air showers. A major contribution to the systematic uncertainties of the absolute energy scale of such experiments is the insufficient knowledge of the fluorescence light yield of electrons in air. The aim of the 5th Fluorescence Workshop was to bring together experimental and theoretical expertise to discuss the latest progress on the investigations of the fluorescence light yield. The results of the workshop will be reviewed as well as the present status of knowledge in this field. Emphasis is given to the fluorescence light yield important for air shower observations and its dependence on atmospheric parameters, like pressure, temperature, and humidity. The effects of the latest results on the light observed from air showers will be discussed.

  6. Efficacy of 45 lm/W Achieved in White OLED

    Broader source: Energy.gov [DOE]

    Universal Display Corporation (UDC) successfully demonstrated an all phosphorescent white organic light emitting diode (WOLED™) with a power efficacy of 45 lm/W at 1,000 cd/m2. This high-efficacy device was enabled by lowering the device operating voltage, increasing the outcoupling efficiency to ~40% from ~20%, and by incorporating highly efficient phosphorescent emitters that are capable of converting nearly all current passing through a WOLED into light.

  7. Integrated ultrasonic particle positioning and low excitation light fluorescence imaging

    SciTech Connect (OSTI)

    Bernassau, A. L.; Al-Rawhani, M.; Beeley, J.; Cumming, D. R. S. [School of Engineering, University of Glasgow, Glasgow, G12 8LT (United Kingdom)] [School of Engineering, University of Glasgow, Glasgow, G12 8LT (United Kingdom)

    2013-12-09T23:59:59.000Z

    A compact hybrid system has been developed to position and detect fluorescent micro-particles by combining a Single Photon Avalanche Diode (SPAD) imager with an acoustic manipulator. The detector comprises a SPAD array, light-emitting diode (LED), lenses, and optical filters. The acoustic device is formed of multiple transducers surrounding an octagonal cavity. By stimulating pairs of transducers simultaneously, an acoustic landscape is created causing fluorescent micro-particles to agglomerate into lines. The fluorescent pattern is excited by a low power LED and detected by the SPAD imager. Our technique combines particle manipulation and visualization in a compact, low power, portable setup.

  8. Ultrahigh resolution multicolor colocalization of single fluorescent probes

    DOE Patents [OSTI]

    Weiss, Shimon; Michalet, Xavier; Lacoste, Thilo D.

    2005-01-18T23:59:59.000Z

    A novel optical ruler based on ultrahigh-resolution colocalization of single fluorescent probes is described. Two unique families of fluorophores are used, namely energy-transfer fluorescent beads and semiconductor nanocrystal (NC) quantum dots, that can be excited by a single laser wavelength but emit at different wavelengths. A novel multicolor sample-scanning confocal microscope was constructed which allows one to image each fluorescent light emitter, free of chromatic aberrations, by scanning the sample with nanometer scale steps using a piezo-scanner. The resulting spots are accurately localized by fitting them to the known shape of the excitation point-spread-function of the microscope.

  9. Fluorescent lamp unit with magnetic field generating means

    DOE Patents [OSTI]

    Grossman, M.W.; George, W.A.

    1989-08-08T23:59:59.000Z

    A fluorescent lamp unit having a magnetic field generating means for improving the performance of the fluorescent lamp is disclosed. In a preferred embodiment the fluorescent lamp comprises four longitudinally extending leg portions disposed in substantially quadrangular columnar array and joined by three generally U-shaped portions disposed in different planes. In another embodiment of the invention the magnetic field generating means comprises a plurality of permanent magnets secured together to form a single columnar structure disposed within a centrally located region defined by the shape of lamp envelope. 4 figs.

  10. Sustainable LED Fluorescent Light Replacement Technology

    SciTech Connect (OSTI)

    None

    2011-06-30T23:59:59.000Z

    Ilumisys and the National Center for Manufacturing Sciences (NCMS) partnered on a three-year project awarded by the United States (U.S.) Department of Energy (DOE), to quantify the impacts of LED lamps, incandescent lamps and fluorescent benchmark lamps over a product lifecycle – i.e. to develop a sustainable design and manufacturing strategy that addresses product manufacturing, use, recycling and disposal scenarios for LED-based lighting. Based on the knowledge gained from extensive product tear-down studies of fluorescent and screw-in lighting products, lifecycle assessment tools, and accelerated lifecycle testing protocols, an interactive Sustainable LED Design Guide has been developed to aid architectural and lighting designers and engineers in making design decisions that consider three important environmental impacts (greenhouse gas emissions, energy use and mercury emission) across all phases of the life of an LED lighting product. Critical information developed for the lifecycle analysis and product feature comparisons is the useful life of the lighting product as well as its performance. The Design Guide is available at www.ncms.org, and was developed based on operational and durability testing of a variety of lighting products including power consumption, light output, and useful life of a lamp in order to allow a more realistic comparison of lamp designs. This report describes the main project tasks, results and innovative features of the lifecycle assessment (LCA)-based design tools, and the key considerations driving the sustainable design of LED lighting systems. The Design Guide incorporates the following three novel features for efficiently evaluating LED lighting features in value-chains: • Bill-of-Materials (BOM) Builder – Designers may import process data for each component and supply functional data for the product, including power, consumption, lumen output and expected useful life. • Environmental Impact Review – Designs are comparable across lifecycle phases, subsystems, and environmental impact category, and can be normalized to a userdefined functional unit. • Drill-down Review – These provide an indepth look at individual lamp designs with the ability to review across subsystem or lifecycle phase.

  11. FY08 Annual Report for Nuclear Resonance Fluorescence Imaging

    SciTech Connect (OSTI)

    Warren, Glen A.; Caggiano, Joseph A.

    2009-01-06T23:59:59.000Z

    FY08 annual report for project the "Nuclear Resonance Fluorescence Imaging" project. Reviews accomplishments of last 3 years, including U-235 signature search, comparison of different photon sources, and examination of NRF measurements using monochromatic photon source.

  12. Calibration of fluorescence resonance energy transfer in microscopy

    DOE Patents [OSTI]

    Youvan, Douglas C. (San Jose, CA); Silva, Christopher M. (Sunnyvale, CA); Bylina, Edward J. (San Jose, CA); Coleman, William J. (Moutain View, CA); Dilworth, Michael R. (Santa Cruz, CA); Yang, Mary M. (San Jose, CA)

    2002-09-24T23:59:59.000Z

    Imaging hardware, software, calibrants, and methods are provided to visualize and quantitate the amount of Fluorescence Resonance Energy Transfer (FRET) occurring between donor and acceptor molecules in epifluorescence microscopy. The MicroFRET system compensates for overlap among donor, acceptor, and FRET spectra using well characterized fluorescent beads as standards in conjunction with radiometrically calibrated image processing techniques. The MicroFRET system also provides precisely machined epifluorescence cubes to maintain proper image registration as the sample is illuminated at the donor and acceptor excitation wavelengths. Algorithms are described that pseudocolor the image to display pixels exhibiting radiometrically-corrected fluorescence emission from the donor (blue), the acceptor (green) and FRET (red). The method is demonstrated on samples exhibiting FRET between genetically engineered derivatives of the Green Fluorescent Protein (GFP) bound to the surface of Ni chelating beads by histidine-tags.

  13. LIGHT-INDUCED CHANGES IN THE FLUORESCENCE YIELD OF

    E-Print Network [OSTI]

    Govindjee

    given during the transient slightly hastens and heightens P. Methyl viologen, an exogenous system I fluorescence intensity is the redox state of Q, the electron acceptor in the system It reaction center (9). Fig

  14. THE HISTORY AND TECHNICAL EVOLUTION OF HIGH FREQUENCY FLUORESCENT LIGHTING

    E-Print Network [OSTI]

    Campbell, John H.

    2011-01-01T23:59:59.000Z

    Dec. 1953. "Hi-Volt-Cycle Lighting ~ Launched i n a Hi-Wide2, F e b r u a r y , 19 53. "Lighting Your Plant with Highg h Frequency Fluorescent Lighting John H. Campbell December

  15. Large core polymer optical backplanes for fluorescence detection

    E-Print Network [OSTI]

    Lee, Kevin Shao-Kwan

    2006-01-01T23:59:59.000Z

    Fluorescence based sensors are used for determining environmental parameters such as dissolved oxygen or pH in biological systems without disturbing a biological system's equilibrium. Recently, there has been a drive to ...

  16. REDUCING INCIDENTAL FLUORESCENCE IN LIVE CELL IMAGING A. Altinok 1

    E-Print Network [OSTI]

    California at Santa Barbara, University of

    , the technique is based on staining bio molecules selectively with proteins carrying fluorescence dyes of known. For instance, length measurements in Fig.1 would lack accuracy since the ends of the objects are blurry within

  17. SHORT COMMUNICATION The Chlorophyll Fluorescence Ratio F735/F700

    E-Print Network [OSTI]

    Gitelson, Anatoly

    sylvatica L.), elm (Ulmus minor 1988; Dahn et al., 1992). In green leaves, about 90% of Miller), and wild of reabsorption of the Chl fluorescence was quan- titatively estimated (Dahn et al., 1992; Gunther et al

  18. Calibration of fluorescence resonance energy transfer in microscopy

    DOE Patents [OSTI]

    Youvan, Dougalas C.; Silva, Christopher M.; Bylina, Edward J.; Coleman, William J.; Dilworth, Michael R.; Yang, Mary M.

    2003-12-09T23:59:59.000Z

    Imaging hardware, software, calibrants, and methods are provided to visualize and quantitate the amount of Fluorescence Resonance Energy Transfer (FRET) occurring between donor and acceptor molecules in epifluorescence microscopy. The MicroFRET system compensates for overlap among donor, acceptor, and FRET spectra using well characterized fluorescent beads as standards in conjunction with radiometrically calibrated image processing techniques. The MicroFRET system also provides precisely machined epifluorescence cubes to maintain proper image registration as the sample is illuminated at the donor and acceptor excitation wavelengths. Algorithms are described that pseudocolor the image to display pixels exhibiting radiometrically-corrected fluorescence emission from the donor (blue), the acceptor (green) and FRET (red). The method is demonstrated on samples exhibiting FRET between genetically engineered derivatives of the Green Fluorescent Protein (GFP) bound to the surface of Ni chelating beads by histidine-tags.

  19. Exploring the mechanome with optical tweezers and single molecule fluorescence

    E-Print Network [OSTI]

    Brau, Ricardo R. (Ricardo Rafael), 1979-

    2008-01-01T23:59:59.000Z

    The combination of optical tweezers and single molecule fluorescence into an instrument capable of making combined, coincident measurements adds an observable dimension that allows for the examination of the localized ...

  20. Protein subcellular localization assays using split fluorescent proteins

    DOE Patents [OSTI]

    Waldo, Geoffrey S. (Santa Fe, NM); Cabantous, Stephanie (Los Alamos, NM)

    2009-09-08T23:59:59.000Z

    The invention provides protein subcellular localization assays using split fluorescent protein systems. The assays are conducted in living cells, do not require fixation and washing steps inherent in existing immunostaining and related techniques, and permit rapid, non-invasive, direct visualization of protein localization in living cells. The split fluorescent protein systems used in the practice of the invention generally comprise two or more self-complementing fragments of a fluorescent protein, such as GFP, wherein one or more of the fragments correspond to one or more beta-strand microdomains and are used to "tag" proteins of interest, and a complementary "assay" fragment of the fluorescent protein. Either or both of the fragments may be functionalized with a subcellular targeting sequence enabling it to be expressed in or directed to a particular subcellular compartment (i.e., the nucleus).

  1. An Enhanced Monomeric Blue Fluorescent Protein with the High Chemical Stability of the Chromophore

    E-Print Network [OSTI]

    Verkhusha, Vladislav V.

    An Enhanced Monomeric Blue Fluorescent Protein with the High Chemical Stability of the Chromophore Commonly used monomeric blue fluorescent proteins suffer from moderate brightness. The brightest of them, m transition from a blue fluorescent state with absorbance at 401 nm to a non-fluorescent state with absorbance

  2. Development of laser excited atomic fluorescence and ionization methods

    SciTech Connect (OSTI)

    Winefordner, J.D.

    1991-01-01T23:59:59.000Z

    Progress report: May 1, 1988 to December 31, 1991. The research supported by DE-FG05-88ER13881 during the past (nearly) 3 years can be divided into the following four categories: (1) theoretical considerations of the ultimate detection powers of laser fluorescence and laser ionization methods; (2) experimental evaluation of laser excited atomic fluorescence; (3) fundamental studies of atomic and molecular parameters in flames and plasmas; (4) other studies.

  3. LucY: A Versatile New Fluorescent Reporter Protein

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Auldridge, Michele E.; Cao, Hongnan; Sen, Saurabh; Franz, Laura P.; Bingman, Craig A.; Yennamalli, Ragothaman M.; Phillips, George N.; Mead, David; Steinmetz, Eric J.; Michnick, Stephen W.

    2015-04-23T23:59:59.000Z

    We report on the discovery, isolation, and use of a novel yellow fluorescent protein. Lucigen Yellow (LucY) binds one FAD molecule within its core, thus shielding it from water and maintaining its structure so that fluorescence is 10-fold higher than freely soluble FAD. LucY displays excitation and emission spectra characteristic of FAD, with 3 excitation peaks at 276nm, 377nm, and 460nm and a single emission peak at 530nm. These excitation and emission maxima provide the large Stokes shift beneficial to fluorescence experimentation. LucY belongs to the MurB family of UDP-N-acetylenolpyruvylglucosamine reductases. The high resolution crystal structure shows that in contrastmore »to other structurally resolved MurB enzymes, LucY does not contain a potentially quenching aromatic residue near the FAD isoalloxazine ring, which may explain its increased fluorescence over related proteins. Using E. coli as a system in which to develop LucY as a reporter, we show that it is amenable to circular permutation and use as a reporter of protein-protein interaction. Fragmentation between its distinct domains renders LucY non-fluorescent, but fluorescence can be partially restored by fusion of the fragments to interacting protein domains. Thus, LucY may find application in Protein-fragment Complementation Assays for evaluating protein-protein interactions.« less

  4. Application of fluorescence microscopy to coal-derived resid characterization

    SciTech Connect (OSTI)

    Rathbone, R.F.; Hower, J.C.; Derbyshire, F.J.

    1991-01-01T23:59:59.000Z

    This study evaluates the usefulness of a fluorescence microscopy methodology to analyze coal-derived resids and interpret the data in the light of liquefaction processing conditions, process response, the inferred resid reactivity, and in relation to results of other analytical data. The fluorescence technique utilized has been widely applied to coal and kerogen characterization, albeit with some modifications, but is novel in its application to the characterization of coal liquids. Fluorescence is the emission of light energy which occurs when electrons, having been excited to a higher energy orbital, return to their lower energy ground state. The majority of organic molecules that fluoresce are those with conjugated double bonds (chromophores), such as aromatics, characterized by pi-electrons less strongly bound within the molecule than sigma electrons, that can be excited to anti-bonding pi-orbitals. Increasing the extent of pi-bond conjugation (i.e. larger molecular size) generally imparts a shift in absorption and emission spectra to longer wavelengths. Resid fluorescence largely depends on the concentration and degree of conjugation of aromatic chromophores in the high molecular weight liquids, possibly with ancillary effects from oxygen functionalities. In this context, fluorescence analysis of liquefaction resids can potentially evaluate process performance, since direct liquefaction processes endeavor to break down the macromolecular structure of coal, and reduce the molecular weight of polycondensed aromatics through hydrogenation, the opening of ring structures, and heteroatom removal.

  5. Application of fluorescence microscopy to coal-derived resid characterization

    SciTech Connect (OSTI)

    Rathbone, R.F.; Hower, J.C.; Derbyshire, F.J.

    1991-12-31T23:59:59.000Z

    This study evaluates the usefulness of a fluorescence microscopy methodology to analyze coal-derived resids and interpret the data in the light of liquefaction processing conditions, process response, the inferred resid reactivity, and in relation to results of other analytical data. The fluorescence technique utilized has been widely applied to coal and kerogen characterization, albeit with some modifications, but is novel in its application to the characterization of coal liquids. Fluorescence is the emission of light energy which occurs when electrons, having been excited to a higher energy orbital, return to their lower energy ground state. The majority of organic molecules that fluoresce are those with conjugated double bonds (chromophores), such as aromatics, characterized by pi-electrons less strongly bound within the molecule than sigma electrons, that can be excited to anti-bonding pi-orbitals. Increasing the extent of pi-bond conjugation (i.e. larger molecular size) generally imparts a shift in absorption and emission spectra to longer wavelengths. Resid fluorescence largely depends on the concentration and degree of conjugation of aromatic chromophores in the high molecular weight liquids, possibly with ancillary effects from oxygen functionalities. In this context, fluorescence analysis of liquefaction resids can potentially evaluate process performance, since direct liquefaction processes endeavor to break down the macromolecular structure of coal, and reduce the molecular weight of polycondensed aromatics through hydrogenation, the opening of ring structures, and heteroatom removal.

  6. Rigidifying Fluorescent Linkers by Metal–Organic Framework Formation for Fluorescence Blue Shift and Quantum Yield Enhancement

    SciTech Connect (OSTI)

    Wei, Zhangwen; Gu, Zhi-Yuan; Arvapally, Ravi K.; Chen, Ying-Pin; Ivy, Joshua F.; Yakovenko, Andrey A.; Feng, Dawei; Omary, Mohammad A.; Zhou, Hong-Cai [UNT

    2014-06-11T23:59:59.000Z

    We demonstrate that rigidifying the structure of fluorescent linkers by structurally constraining them in metal–organic frameworks (MOFs) to control their conformation effectively tunes the fluorescence energy and enhances the quantum yield. Thus, a new tetraphenylethylene-based zirconium MOF exhibits a deep-blue fluorescent emission at 470 nm with a unity quantum yield (99.9 ± 0.5%) under Ar, representing ca. 3600 cm?¹ blue shift and doubled radiative decay efficiency vs the linker precursor. An anomalous increase in the fluorescence lifetime and relative intensity takes place upon heating the solid MOF from cryogenic to ambient temperatures. The origin of these unusual photoluminescence properties is attributed to twisted linker conformation, intramolecular hindrance, and framework rigidity.

  7. Cyanine-based probe\\tag-peptide pair fluorescence protein imaging and fluorescence protein imaging methods

    DOE Patents [OSTI]

    Mayer-Cumblidge, M. Uljana; Cao, Haishi

    2013-01-15T23:59:59.000Z

    A molecular probe comprises two arsenic atoms and at least one cyanine based moiety. A method of producing a molecular probe includes providing a molecule having a first formula, treating the molecule with HgOAc, and subsequently transmetallizing with AsCl.sub.3. The As is liganded to ethanedithiol to produce a probe having a second formula. A method of labeling a peptide includes providing a peptide comprising a tag sequence and contacting the peptide with a biarsenical molecular probe. A complex is formed comprising the tag sequence and the molecular probe. A method of studying a peptide includes providing a mixture containing a peptide comprising a peptide tag sequence, adding a biarsenical probe to the mixture, and monitoring the fluorescence of the mixture.

  8. The therapeutic efficacy of camptothecin-encapsulated supramolecular nanoparticles

    E-Print Network [OSTI]

    Cheng, Jianjun

    The therapeutic efficacy of camptothecin-encapsulated supramolecular nanoparticles Kuan-Ju Chen a,1 of Materials Science and Engineering, University of Illinois at Urbana-Champaign-Urbana, 1304 West Green Street October 2011 Available online 8 November 2011 Keywords: Supramolecular assembly Nanoparticles Drug

  9. Formalizing Concepts for Efficacy-aware Business Process Modeling

    E-Print Network [OSTI]

    Ulm, Universität

    Formalizing Concepts for Efficacy-aware Business Process Modeling Matthias Lohrmann and Manfred.lohrmann,manfred.reichert}@uni-ulm.de Abstract. In business process design, business objective models can ful- fill the role of formal business process management concepts yet. Moreover, process models are currently not sufficiently

  10. Phytotoxicity and Efficacy of Sumagic (Uniconazole) for Growth Control of

    E-Print Network [OSTI]

    Lieth, J. Heinrich

    Phytotoxicity and Efficacy of Sumagic (Uniconazole) for Growth Control of Mexican Sage (Salvia Bush Sage Salvia leucantha cv. `Santa Barbara' REASON: Height Control SOIL TYPE OR TYPE OF POTTING MIX: UC Mix % SAND 30 % SILT % CLAY % OM 70 pH 6.5 SEEDING DATE EMERGENCE DATE TRANSPLANTING DATE: 3

  11. Efficacy and Phytotoxicity of Sumagic (Uniconazole) for Growth Control of

    E-Print Network [OSTI]

    Lieth, J. Heinrich

    Efficacy and Phytotoxicity of Sumagic (Uniconazole) for Growth Control of Egyptian Star Star-Cluster Pentas lanceolata cv. `Butterfly Pink' REASON: Control of vegetative growth SOIL TYPE OR TYPE OF POTTING MIX: UC Mix % SAND 30 % SILT % CLAY % OM 70 pH 6.5 SEEDING DATE EMERGENCE DATE

  12. Laser-induced differential normalized fluorescence method for cancer diagnosis

    DOE Patents [OSTI]

    Vo-Dinh, T.; Panjehpour, M.; Overholt, B.F.

    1996-12-03T23:59:59.000Z

    An apparatus and method for cancer diagnosis are disclosed. The diagnostic method includes the steps of irradiating a tissue sample with monochromatic excitation light, producing a laser-induced fluorescence spectrum from emission radiation generated by interaction of the excitation light with the tissue sample, and dividing the intensity at each wavelength of the laser-induced fluorescence spectrum by the integrated area under the laser-induced fluorescence spectrum to produce a normalized spectrum. A mathematical difference between the normalized spectrum and an average value of a reference set of normalized spectra which correspond to normal tissues is calculated, which provides for amplifying small changes in weak signals from malignant tissues for improved analysis. The calculated differential normalized spectrum is correlated to a specific condition of a tissue sample. 5 figs.

  13. Laser-induced differential normalized fluorescence method for cancer diagnosis

    DOE Patents [OSTI]

    Vo-Dinh, Tuan (Knoxville, TN); Panjehpour, Masoud (Knoxville, TN); Overholt, Bergein F. (Knoxville, TN)

    1996-01-01T23:59:59.000Z

    An apparatus and method for cancer diagnosis are disclosed. The diagnostic method includes the steps of irradiating a tissue sample with monochromatic excitation light, producing a laser-induced fluorescence spectrum from emission radiation generated by interaction of the excitation light with the tissue sample, and dividing the intensity at each wavelength of the laser-induced fluorescence spectrum by the integrated area under the laser-induced fluorescence spectrum to produce a normalized spectrum. A mathematical difference between the normalized spectrum and an average value of a reference set of normalized spectra which correspond to normal tissues is calculated, which provides for amplifying small changes in weak signals from malignant tissues for improved analysis. The calculated differential normalized spectrum is correlated to a specific condition of a tissue sample.

  14. Engineering and Characterization of a Superfolder Green Fluorescent Protein

    SciTech Connect (OSTI)

    Pedelacq,J.; Cabantous, S.; Tran, T.; Terwilliger, T.; Waldo, G.

    2006-01-01T23:59:59.000Z

    Existing variants of green fluorescent protein (GFP) often misfold when expressed as fusions with other proteins. We have generated a robustly folded version of GFP, called 'superfolder' GFP, that folds well even when fused to poorly folded polypeptides. Compared to 'folding reporter' GFP, a folding-enhanced GFP containing the 'cycle-3' mutations and the 'enhanced GFP' mutations F64L and S65T, superfolder GFP shows improved tolerance of circular permutation, greater resistance to chemical denaturants and improved folding kinetics. The fluorescence of Escherichia coli cells expressing each of eighteen proteins from Pyrobaculum aerophilum as fusions with superfolder GFP was proportional to total protein expression. In contrast, fluorescence of folding reporter GFP fusion proteins was strongly correlated with the productive folding yield of the passenger protein. X-ray crystallographic structural analyses helped explain the enhanced folding of superfolder GFP relative to folding reporter GFP.

  15. Fluorescent single walled nanotube/silica composite materials

    SciTech Connect (OSTI)

    Dattelbaum, Andrew M.; Gupta, Gautam; Duque, Juan G.; Doorn, Stephen K.; Hamilton, Christopher E.; DeFriend Obrey, Kimberly A.

    2013-03-12T23:59:59.000Z

    Fluorescent composites of surfactant-wrapped single-walled carbon nanotubes (SWNTs) were prepared by exposing suspensions of surfactant-wrapped carbon nanotubes to tetramethylorthosilicate (TMOS) vapor. Sodium deoxycholate (DOC) and sodium dodecylsulphate (SDS) were the surfactants. No loss in emission intensity was observed when the suspension of DOC-wrapped SWNTs were exposed to the TMOS vapors, but about a 50% decrease in the emission signal was observed from the SDS-wrapped SWNTs nanotubes. The decrease in emission was minimal by buffering the SDS/SWNT suspension prior to forming the composite. Fluorescent xerogels were prepared by adding glycerol to the SWNT suspensions prior to TMOS vapor exposure, followed by drying the gels. Fluorescent aerogels were prepared by replacing water in the gels with methanol and then exposing them to supercritical fluid drying conditions. The aerogels can be used for gas sensing.

  16. Photosynthesis: Research for Food, Fuel and Future--15th International Conference on Photosynthesis518 FLIM (Fluorescence Lifetime Imaging Microscopy) of Avocado Leaves during Slow

    E-Print Network [OSTI]

    Govindjee

    518 FLIM (Fluorescence Lifetime Imaging Microscopy) of Avocado Leaves during Slow Fluorescence avocado leaves (Persea americana Mill.) during the slow part of chlorophyll (Chl) a fluorescence transient

  17. Nuclear Resonance Fluorescence for Safeguards Applications

    SciTech Connect (OSTI)

    Ludewigt, Bernhard A; Quiter, Brian J; Ambers, Scott D

    2011-02-04T23:59:59.000Z

    In nuclear resonance fluorescence (NRF) measurements, resonances are excited by an external photon beam leading to the emission of {gamma} rays with specific energies that are characteristic of the emitting isotope. The promise of NRF as a non-destructive analysis technique (NDA) in safeguards applications lies in its potential to directly quantify a specific isotope in an assay target without the need for unfolding the combined responses of several fissile isotopes as often required by other NDA methods. The use of NRF for detection of sensitive nuclear materials and other contraband has been researched in the past. In the safeguards applications considered here one has to go beyond mere detection and precisely quantify the isotopic content, a challenge that is discussed throughout this report. Basic NRF measurement methods, instrumentation, and the analytical calculation of NRF signal strengths are described in Section 2. Well understood modeling and simulation tools are needed for assessing the potential of NRF for safeguards and for designing measurement systems. All our simulations were performed with the radiation transport code MCNPX, a code that is widely used in the safeguards community. Our initial studies showed that MCNPX grossly underestimated the elastically scattered background at backwards angles due to an incorrect treatment of Rayleigh scattering. While new, corrected calculations based on ENDF form factors showed much better agreement with experimental data for the elastic scattering of photons on an uranium target, the elastic backscatter is still not rigorously treated. Photonuclear scattering processes (nuclear Thomson, Delbruck and Giant Dipole Resonance scattering), which are expected to play an important role at higher energies, are not yet included. These missing elastic scattering contributions were studied and their importance evaluated evaluated against data found in the literature as discussed in Section 3. A transmission experiment was performed in September 2009 to test and demonstrate the applicability of the method to the quantitative measurement of an isotope of interest embedded in a thick target. The experiment, data analysis, and results are described in Section 4. The broad goal of our NRF studies is to assess the potential of the technique in safeguards applications. Three examples are analyzed in Section 5: the isotopic assay of spent nuclear fuel (SNF), the measurement of {sup 235}U enrichment in UF{sub 6} cylinders, and the determination of {sup 239}Pu in mixed oxide (MOX) fuel. The study of NRF for the assay of SNF assemblies was supported by the Next Generation Safeguards Initiative (NGSI) of the U.S. Department of Energy as part of a large multi-lab/university effort to quantify the plutonium (Pu) mass in spent nuclear fuel assemblies and to detect the diversion of pins with non-destructive assay (NDA) methods. NRF is one of 14 NDA techniques being researched. The methodology for performing and analyzing quantitative NRF measurements was developed for determining Pu mass in SNF and is extensively discussed in this report. The same methodology was applied to the assessment of NRF for the measurement of {sup 235}U enrichment and the determination of {sup 239}Pu in MOX fuel. The analysis centers on determining suitable NRF measurement methods, measurement capabilities that could be realized with currently available instrumentation, and photon source and detector requirements for achieving useful NDA capabilities.

  18. Heat transfer assembly for a fluorescent lamp and fixture

    DOE Patents [OSTI]

    Siminovitch, M.J.; Rubenstein, F.M.; Whitman, R.E.

    1992-12-29T23:59:59.000Z

    In a lighting fixture including a lamp and a housing, a heat transfer structure is disclosed for reducing the minimum lamp wall temperature of a fluorescent light bulb. The heat transfer structure, constructed of thermally conductive material, extends from inside the housing to outside the housing, transferring heat energy generated from a fluorescent light bulb to outside the housing where the heat energy is dissipated to the ambient air outside the housing. Also disclosed is a method for reducing minimum lamp wall temperatures. Further disclosed is an improved lighting fixture including a lamp, a housing and the aforementioned heat transfer structure. 11 figs.

  19. An Event Reconstruction Method for the Telescope Array Fluorescence Detectors

    SciTech Connect (OSTI)

    Fujii, T.; Ogio, S.; Yamazaki, K. [Graduate Schiool of Science, Osaka City University, Sumiyoshi, Osaka 558-8585 (Japan); Fukushima, M.; Ikeda, D.; Sagawa, H.; Takahashi, Y.; Tameda, Y. [Institute of Cosmic Ray Research, University of Tokyo, Kashiwa, Chiba 277-8582 (Japan); Hayashi, K.; Ishimori, R.; Kobayashi, Y.; Tokuno, H.; Tsunesada, Y. [Graduate School of Science and Engineering, Tokyo Institute of Technology, Meguro, Tokyo 152-8551 (Japan); Honda, K.; Tomida, T. [Graduate School of Medicine and Engineering, University of Yamanashi, Kofu, Yamanashi 400-8511 (Japan); Udo, S. [Faculty of Engineering, Kanagawa University, Yokohama, Kanagawa 221-8686 (Japan)

    2011-09-22T23:59:59.000Z

    We measure arrival directions, energies and mass composition of ultra-high energy cosmic rays with air fluorescence detector telescopes. The longitudinal profile of the cosmic ray induced extensive air shower cascade is imaged on focal plane of the telescope camera. Here, we show an event reconstruction method to obtain the primary information from data collected by the Telescope Array Fluorescence Detectors. In particular, we report on an ''Inverse Monte Carlo (IMC)'' method in which the reconstruction process searches for an optimum solution via repeated Monte Carlo simulations including characteristics of all detectors, atmospheric conditions, photon emission and scattering processes.

  20. Longitudinal Shower Profile Reconstruction from Fluorescence and Cherenkov Light

    E-Print Network [OSTI]

    M. Unger; R. Engel; F. Schüssler; R. Ulrich

    2007-06-11T23:59:59.000Z

    Traditionally, longitudinal shower profiles are reconstructed in fluorescence light experiments by treating the Cherenkov light contribution as background. Here we will argue that, due to universality of the energy spectra of electrons and positrons, both fluorescence and Cherenkov light can be used simultaneously as signal to infer the longitudinal shower development. We present a new profile reconstruction method that is based on the analytic least-square solution for the estimation of the shower profile from the observed light signal and discuss the extrapolation of the profile with a Gaisser-Hillas function.

  1. A versatile detector for total fluorescence and electron yield experiments

    SciTech Connect (OSTI)

    Thielemann, N. [Institute for Methods and Instrumentation for Synchrotron Radiation Research, Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, Albert-Einstein-Str. 15, 12489 Berlin (Germany); Institut fuer Physik, Humboldt-Universitaet zu Berlin, Newtonstrasse 15, 12489 Berlin (Germany); Hoffmann, P. [Institute for Methods and Instrumentation for Synchrotron Radiation Research, Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, Albert-Einstein-Str. 15, 12489 Berlin (Germany); Foehlisch, A. [Institute for Methods and Instrumentation for Synchrotron Radiation Research, Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, Albert-Einstein-Str. 15, 12489 Berlin (Germany); Institut fuer Physik und Astronomie, Universitaet Potsdam, Karl-Liebknecht-Strasse 24-25, 14476 Potsdam (Germany)

    2012-09-15T23:59:59.000Z

    The combination of a non-coated silicon photodiode with electron repelling meshes makes a versatile detector for total fluorescence yield and electron yield techniques highly suitable for x-ray absorption spectroscopy. In particular, a copper mesh with a bias voltage allows to suppress or transmit the electron yield signal. The performance of this detection scheme has been characterized by near edge x-ray absorption fine structure studies of thermal oxidized silicon and sapphire. The results show that the new detector probes both electron yield and for a bias voltage exceeding the maximum photon energy the total fluorescence yield.

  2. Heat transfer assembly for a fluorescent lamp and fixture

    SciTech Connect (OSTI)

    Siminovitch, Michael J. (Richmond, CA); Rubenstein, Francis M. (Berkeley, CA); Whitman, Richard E. (Richmond, CA)

    1992-01-01T23:59:59.000Z

    In a lighting fixture including a lamp and a housing, a heat transfer structure is disclosed for reducing the minimum lamp wall temperature of a fluorescent light bulb. The heat transfer structure, constructed of thermally conductive material, extends from inside the housing to outside the housing, transferring heat energy generated from a fluorescent light bulb to outside the housing where the heat energy is dissipated to the ambient air outside the housing. Also disclosed is a method for reducing minimum lamp wall temperatures. Further disclosed is an improved lighting fixture including a lamp, a housing and the aforementioned heat transfer structure.

  3. Inves&ga&ng the Trade-Off between Luminous Efficacy of Radia&on

    E-Print Network [OSTI]

    California at Davis, University of

    Inves&ga&ng the Trade-Off between Luminous Efficacy of Radia&on and Color;Luminous Efficacy of Radia&on (LER) / Color Rendering Index (CRI) Trade-off study CCT = 3500 K How can we experimentally test this? #12;Luminous Efficacy

  4. Fluorescent Dye Encapsulated ZnO Particles with Cell-specific...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    the visible fluorescence emission of the dye or UV fluorescence emission of ZnO, and anti-cancerantibacterial treatments using the selective toxicity of the nanoscale ZnO outer...

  5. Classification with Artificial Neural Networks and Support Vector Machines: application to oil fluorescence spectra

    E-Print Network [OSTI]

    Oldenburg, Carl von Ossietzky Universität

    methods to examine crude oils, heavy refined oils, and sludge oils: the channels relationships method (CRMClassification with Artificial Neural Networks and Support Vector Machines: application to oil, and Oil fluorescence ABSTRACT: This paper reports on oil classification with fluorescence spectroscopy

  6. Detection of Ethylene Gas by Fluorescence Turn-On of a Conjugated Polymer

    E-Print Network [OSTI]

    Swager, Timothy Manning

    Ripe fruits: The fluorescence of a conjugated polymer is quenched by the presence of copper(I) moieties. Upon exposure to ethylene gas the copper complexes bind to ethylene and no longer quench the polymer fluorescence ...

  7. Extending the utility of enzymes for site-specific targeting of fluorescent probes

    E-Print Network [OSTI]

    Liu, Daniel S. (Daniel Shao-Chen)

    2014-01-01T23:59:59.000Z

    Genetically encodable fluorescence reporters such as the green fluorescent protein (GFP) are useful for studying protein expression, localization, and dynamics in a variety of biological systems. GFP and its related variants, ...

  8. Surfactant Diffusion into Lysozyme Crystal Matrices Investigated by Quantitative Fluorescence Microscopy

    E-Print Network [OSTI]

    Velev, Orlin D.

    the infusion of lysozyme crystals with pyrene-based fluorescent surfactants by quantitative fluorescence × 10-10 to 30 × 10-10 cm2 /s, depending on the type and size of the surfactant. The slow infusion

  9. Optical gating of perylene bisimide fluorescence using dithienylcyclopentene photochromic switches

    SciTech Connect (OSTI)

    Pärs, Martti; Köhler, Jürgen, E-mail: juergen.koehler@uni-bayreuth.de [Experimental Physics IV, University of Bayreuth, 95440 Bayreuth (Germany)] [Experimental Physics IV, University of Bayreuth, 95440 Bayreuth (Germany); Gräf, Katja; Bauer, Peter; Thelakkat, Mukundan [Applied Functional Polymers, University of Bayreuth, 95440 Bayreuth (Germany)] [Applied Functional Polymers, University of Bayreuth, 95440 Bayreuth (Germany)

    2013-11-25T23:59:59.000Z

    The emission of millions of fluorescence photons from a chromophore is controlled by the absorption of a few tens of photons in a photochromic molecule. The parameters that determine the efficiency of this process are investigated, providing insights for the development of an all-optical gate.

  10. EMERGING TECHNOLOGIES Two-photon excitation chlorophyll fluorescence lifetime imaging

    E-Print Network [OSTI]

    Qu, Jianan

    at higher Cd concentration was clearly identified. The decay of chlorophyll fluorescence extracted from) toxicity Abbreviations Cd Cadmium PS Photosystem LHCII Light-harvesting complex II PAM Pulse and Computer Engineering, Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon

  11. Diffusion of Polymer-Coated Nanoparticles Studied by Fluorescence Correlation

    E-Print Network [OSTI]

    Granick, Steve

    Diffusion of Polymer-Coated Nanoparticles Studied by Fluorescence Correlation Spectroscopy Jiang of Brownian motion of polystyrene nanoparticles is controlled by tuning their hydro- dynamic radius through coefficient of the particles. This study has initiated our further studies on the interaction of nanoparticles

  12. Aqueous Ferrofluid of Magnetite Nanoparticles: Fluorescence Labeling and Magnetophoretic Control

    E-Print Network [OSTI]

    Swihart, Mark T.

    functionalization of magnetite nanoparticles using citric acid to produce a stable aqueous dispersionAqueous Ferrofluid of Magnetite Nanoparticles: Fluorescence Labeling and Magnetophoretic ControlVed: October 8, 2004 A method is presented for the preparation of a biocompatible ferrofluid containing dye-functionalized

  13. Classification of Protein Localization Patterns Obtained via Fluorescence Light Microscopy

    E-Print Network [OSTI]

    Gordon, Geoffrey J.

    of the microscope. They should also be in- sensitive to the wide variability in cell morphology that is present in fluores- cence light microscope images of mammalian cells. Such images are generated on a regular basis by labeling one or more subcellular structures with fluorescent dyes and then collecting images

  14. Convection venting lensed reflector-type compact fluorescent lamp system

    DOE Patents [OSTI]

    Pelton, B.A.; Siminovitch, M.

    1997-07-29T23:59:59.000Z

    Disclosed herein is a fluorescent lamp housing assembly capable of providing convection cooling to the lamp and the ballast. The lens of the present invention includes two distinct portions, a central portion and an apertured portion. The housing assembly further includes apertures so that air mass is able to freely move up through the assembly and out ventilation apertures. 12 figs.

  15. Convection venting lensed reflector-type compact fluorescent lamp system

    DOE Patents [OSTI]

    Pelton, Bruce A. (825 Manor Rd., El Sobrante, CA 94803); Siminovitch, Michael (829 Manor Rd., El Sobrante, CA 94803)

    1997-01-01T23:59:59.000Z

    Disclosed herein is a fluorescent lamp housing assembly capable of providing convection cooling to the lamp and the ballast. The lens of the present invention includes two distinct portions, a central portion and an apertured portion. The housing assembly further includes apertures so that air mass is able to freely move up through the assembly and out ventilation apertures.

  16. Cellubrevin-targeted Fluorescence Uncovers Heterogeneity in the Recycling Endosomes*

    E-Print Network [OSTI]

    Machen, Terry E.

    Cellubrevin-targeted Fluorescence Uncovers Heterogeneity in the Recycling Endosomes* (Received, University of California, Berkeley, California 94720-3200 The pH and trafficking of recycling endosomes have-enriched recycling endosomes (pHCb) and FITC-transferrin to measure the pH of transferrin- enriched recycling

  17. Enhanced Archaerhodopsin Fluorescent Protein Voltage Yiyang Gong1,2*

    E-Print Network [OSTI]

    Ferrari, Silvia

    Enhanced Archaerhodopsin Fluorescent Protein Voltage Indicators Yiyang Gong1,2* , Jin Zhong Li1 by nearly three-fold in comparison to Arch-D95N. Citation: Gong Y, Li JZ, Schnitzer MJ (2013) Enhanced; Published June 19, 2013 Copyright: © 2013 Gong et al. This is an open-access article distributed under

  18. Identication of Major Water-Soluble Fluorescent Components of Some

    E-Print Network [OSTI]

    Myrick, Michael Lenn

    limits for PAHs in water are in the parts-per-billion to parts-per- trillion range for a varietyIdenti®cation of Major Water-Soluble Fluorescent Components of Some Petrochemicals M. GRONER, A. R the ultraviolet (UV) ¯uorescence of water after exposure to gasoline, diesel fuel and crude oil are pre- sented

  19. Automatically Identifying Scatter in Fluorescence Data using Robust Techniques.

    E-Print Network [OSTI]

    (PARAFAC) to fluorescence excitation-emission data (EEM). The scatter does not contain any relevant handle first and second order Rayleigh scatter as well as Raman scatter in various types of EEM data of such a measurement is an excitation-emission matrix (EEM). When several samples (I) are mea- sured the data can

  20. Laser fluorescence EEM probe for cone penetrometer pollution analysis

    SciTech Connect (OSTI)

    Lin, J.; Hart, S.J.; Taylor, T.A.; Kenny, J.E. [Tufts Univ., Medford, MA (United States). Dept. of Chemistry

    1995-12-31T23:59:59.000Z

    A laser-induced fluorescence (LIF) excitation-emission matrix (EEM) probe has been developed in the laboratory, and installed and tested in a cone penetrometer. The laser excitation system uses the fourth harmonic of a flashlamp-pumped Nd:YAG laser (at 266 nm) to pump a Raman shifter. Up to ten laser beams (in the wavelength region of 257 to 400 nm) from the Raman shifter are launched into optical fibers that are connected to the optical fibers of the cone penetrometer probe through standard connectors. In the probe head, the laser radiation is focused onto the outer surface of sapphire windows that are in contact with the soils. The fluorescence emission is collected by ten collection fibers that take the fluorescence to a detection system consisting of a spectrograph and a CCD detector. This probe allows real-time collection of LIF-EEMs of pollutants adsorbed on solids or dissolved in groundwater. LIF-EEMs provide a substantial amount of spectral information that can be used to determine the composition and quantity of pollutants in soils. This probe can be used to measure POL (petroleum, oil, lubricants), PAH (polycyclic aromatic hydrocarbons), and other fluorescent pollutants. The LIF-EEM instrument has been developed in the laboratory, and installed in a cone penetrometer truck for a field test at Hill Air Force Base, Utah. The experience of the test will be discussed.

  1. Optimal resolution in Fresnel incoherent correlation holographic fluorescence microscopy

    E-Print Network [OSTI]

    Rosen, Joseph

    Optimal resolution in Fresnel incoherent correlation holographic fluorescence microscopy Gary, Israel 4 rosen@ee.bgu.ac.il *gbrooker@jhu.edu Abstract: Fresnel Incoherent Correlation Holography (FINCH. Rosen and G. Brooker, "Digital spatially incoherent Fresnel holography," Opt. Lett. 32(8), 912­914 (2007

  2. Amplifying Fluorescent Polymers Direct Synthesis of an OligonucleotidePoly-

    E-Print Network [OSTI]

    Tan, Weihong

    Amplifying Fluorescent Polymers Direct Synthesis of an Oligonucleotide­Poly- (phenylene ethynylene bioprobes can be constructed with these polymers for selective target recog- nition. To achieve this objective, the polymer must be conjugated with a biomolecule such as a DNA strand, a peptide, or a protein

  3. Automated hybridization/imaging device for fluorescent multiplex DNA sequencing

    DOE Patents [OSTI]

    Weiss, R.B.; Kimball, A.W.; Gesteland, R.F.; Ferguson, F.M.; Dunn, D.M.; Di Sera, L.J.; Cherry, J.L.

    1995-11-28T23:59:59.000Z

    A method is disclosed for automated multiplex sequencing of DNA with an integrated automated imaging hybridization chamber system. This system comprises an hybridization chamber device for mounting a membrane containing size-fractionated multiplex sequencing reaction products, apparatus for fluid delivery to the chamber device, imaging apparatus for light delivery to the membrane and image recording of fluorescence emanating from the membrane while in the chamber device, and programmable controller apparatus for controlling operation of the system. The multiplex reaction products are hybridized with a probe, the enzyme (such as alkaline phosphatase) is bound to a binding moiety on the probe, and a fluorogenic substrate (such as a benzothiazole derivative) is introduced into the chamber device by the fluid delivery apparatus. The enzyme converts the fluorogenic substrate into a fluorescent product which, when illuminated in the chamber device with a beam of light from the imaging apparatus, excites fluorescence of the fluorescent product to produce a pattern of hybridization. The pattern of hybridization is imaged by a CCD camera component of the imaging apparatus to obtain a series of digital signals. These signals are converted by the controller apparatus into a string of nucleotides corresponding to the nucleotide sequence an automated sequence reader. The method and apparatus are also applicable to other membrane-based applications such as colony and plaque hybridization and Southern, Northern, and Western blots. 9 figs.

  4. Automated hybridization/imaging device for fluorescent multiplex DNA sequencing

    DOE Patents [OSTI]

    Weiss, Robert B. (Salt Lake City, UT); Kimball, Alvin W. (Salt Lake City, UT); Gesteland, Raymond F. (Salt Lake City, UT); Ferguson, F. Mark (Salt Lake City, UT); Dunn, Diane M. (West Valley City, UT); Di Sera, Leonard J. (Salt Lake City, UT); Cherry, Joshua L. (Salt Lake City, UT)

    1995-01-01T23:59:59.000Z

    A method is disclosed for automated multiplex sequencing of DNA with an integrated automated imaging hybridization chamber system. This system comprises an hybridization chamber device for mounting a membrane containing size-fractionated multiplex sequencing reaction products, apparatus for fluid delivery to the chamber device, imaging apparatus for light delivery to the membrane and image recording of fluorescence emanating from the membrane while in the chamber device, and programmable controller apparatus for controlling operation of the system. The multiplex reaction products are hybridized with a probe, then an enzyme (such as alkaline phosphatase) is bound to a binding moiety on the probe, and a fluorogenic substrate (such as a benzothiazole derivative) is introduced into the chamber device by the fluid delivery apparatus. The enzyme converts the fluorogenic substrate into a fluorescent product which, when illuminated in the chamber device with a beam of light from the imaging apparatus, excites fluorescence of the fluorescent product to produce a pattern of hybridization. The pattern of hybridization is imaged by a CCD camera component of the imaging apparatus to obtain a series of digital signals. These signals are converted by the controller apparatus into a string of nucleotides corresponding to the nucleotide sequence an automated sequence reader. The method and apparatus are also applicable to other membrane-based applications such as colony and plaque hybridization and Southern, Northern, and Western blots.

  5. REGULAR PAPER Modulation of the fluorescence yield in heliobacterial cells

    E-Print Network [OSTI]

    . They are thought to use a light-driven cyclic electron transport pathway to pump protons, and thereby phos brief flashes is inversely correlated to the variable fluorescence. Using pump-probe spectros- copy), or conversion to heat. When photosynthetic systems are operating efficiently, photochemistry dominates

  6. Assaying protein import into mitochondria using fluorescence spectroscopy

    E-Print Network [OSTI]

    Cargill, Holly Beth

    2006-08-16T23:59:59.000Z

    of the Outer Membrane (TOM) complex, and the inner mitochondrial membrane (IM) via the Translocase of the Inner Membrane 23 (TIM23) complex. A novel system was set up to examine the import of matrix-targeted preproteins into mitochondria using fluorescence...

  7. Quantitative high dynamic range beam profiling for fluorescence microscopy

    SciTech Connect (OSTI)

    Mitchell, T. J., E-mail: t.j.mitchell@dur.ac.uk; Saunter, C. D.; O’Nions, W.; Girkin, J. M.; Love, G. D. [Centre for Advanced Instrumentation and Biophysical Sciences Institute, Department of Physics, Durham University, Durham DH1 3LE (United Kingdom)

    2014-10-15T23:59:59.000Z

    Modern developmental biology relies on optically sectioning fluorescence microscope techniques to produce non-destructive in vivo images of developing specimens at high resolution in three dimensions. As optimal performance of these techniques is reliant on the three-dimensional (3D) intensity profile of the illumination employed, the ability to directly record and analyze these profiles is of great use to the fluorescence microscopist or instrument builder. Though excitation beam profiles can be measured indirectly using a sample of fluorescent beads and recording the emission along the microscope detection path, we demonstrate an alternative approach where a miniature camera sensor is used directly within the illumination beam. Measurements taken using our approach are solely concerned with the illumination optics as the detection optics are not involved. We present a miniature beam profiling device and high dynamic range flux reconstruction algorithm that together are capable of accurately reproducing quantitative 3D flux maps over a large focal volume. Performance of this beam profiling system is verified within an optical test bench and demonstrated for fluorescence microscopy by profiling the low NA illumination beam of a single plane illumination microscope. The generality and success of this approach showcases a widely flexible beam amplitude diagnostic tool for use within the life sciences.

  8. SSL Pricing and Efficacy Trend Analysis for Utility Program Planning

    SciTech Connect (OSTI)

    Tuenge, Jason R.

    2013-10-01T23:59:59.000Z

    An LED lamp or luminaire can generally be found that matches or exceeds the efficacy of benchmark technologies in a given product category, and LED products continue to expand into ever-higher lumen output niches. However, the price premium for LED continues to pose a barrier to adoption in many applications, in spite of expected savings from reduced energy use and maintenance. Other factors—such as dimmability and quality of light—can also present challenges. The appropriate type, timing, and magnitude of energy efficiency activities will vary from organization to organization based on local variables and the method of evaluation. A number of factors merit consideration when prioritizing activities for development. Category-specific projections for pricing and efficacy are provided herein to assist in efficiency program planning efforts.

  9. Detection of counterfeit U.S. paper money using intrinsic fluorescence lifetime

    E-Print Network [OSTI]

    Levene, Michael J.

    -photon spectral and lifetime fluorescence microscopy," Appl. Opt. 43(27), 5173­5182 (2004). #118121 - $15.00 USD

  10. Caged Molecular Fluorescence Velocimetry to measure meso-to micro-scale thermal flow fields

    E-Print Network [OSTI]

    Park, Jaesung

    2000-01-01T23:59:59.000Z

    (CPL). The system utilizes a microscope objective lens, caged molecular fluorescence probes, Nd:YAG laser for UV light source, Ar-ion laser for 488 nm fluorescence pumping, and a color CCD camera to record a series of fluorescent images. Caged...

  11. 428 BIOCHIMICAET BIOPHYSICAACTA pH CONTROL OF THE CHLOROPHYLL a FLUORESCENCE IN ALGAE

    E-Print Network [OSTI]

    Govindjee

    428 BIOCHIMICAET BIOPHYSICAACTA BBA 46126 pH CONTROL OF THE CHLOROPHYLL a FLUORESCENCE IN ALGAE on the "slow" (min) time course of Chlorophyll a fluorescence yield in the green alga Chlorella pyrenoidosa and in the blue-green alga Anacystis nidulans. In Chlorella, the decay of fluorescence yield, in the I- to 5-rain

  12. Fluorescence Behavioral Imaging (FBI) Tracks Identity in Heterogeneous Groups of Drosophila

    E-Print Network [OSTI]

    Floreano, Dario

    Fluorescence Behavioral Imaging (FBI) Tracks Identity in Heterogeneous Groups of Drosophila Pavan describe Fluorescence Behavioral Imaging (FBI), a toolkit that uses transgenic fluorescence to discriminate-source software for automated, high-accuracy determination of genetic identity. Using FBI, we measure courtship

  13. Fluorescence quenching of water-soluble porphyrins. A novel fluorescence quenching of anionic porphyrin by anionic anthraquinone

    SciTech Connect (OSTI)

    Kano, K.; Sato, T.; Yamada, S.; Ogawa, T.

    1983-02-17T23:59:59.000Z

    The fluorescence quenching of 5-phenyl-10,15,20-tris(p-sulfonatophenyl)porphine (TPPS/sup 3 -/) and 5,10,15,20-tetrakis(4-N-methylpyridyl)porphine (TMPyP/sup 4 +/) has been studied in water (pH 8.0) by using 9,10-anthra-quinone-2,6-disulfonate (AQDS/sup 2 -/) and methyl viologen (MV/sup 2 +/) as quenchers. While electrostatic repulsion is expected, AQDS/sup 2 -/ quenched the TPPS/sup 3 -/ fluorescence more efficiently than MV/sup 2 +/. The steady-state and time-resolved fluorescence measurements indicated that static quenching took place in the TPPS/sup 3 -/-AQDS/sup 2 -/ system. Studies on the absorption spectra and the effects of ionic strength on the fluorescence quenching indicated the formation of the ground-state complex of TPPS/sup 3 -/ and AQDS/sup 2 -/. The thermodynamic parameters (..delta..H and ..delta..S) suggested that the ground-state complex was formed via van der Walls interaction.

  14. Fluorescent Probe Solubilization in the Headgroup and Core Regions of Micelles: Fluorescence Lifetime and Orientational Relaxation Measurements

    E-Print Network [OSTI]

    Fayer, Michael D.

    the microheterogeneous medium under investigation. To ascertain that the probe is located in the target environment in the hydrocarbon core region of the micelle. In this environment the chromophores have a considerably longer to be applied successfully, the fluorescent molecule must be tailored to probe the desired environment within

  15. Coded Aperture Imaging for Fluorescent X-rays-Biomedical Applications

    SciTech Connect (OSTI)

    Haboub, Abdel; MacDowell, Alastair; Marchesini, Stefano; Parkinson, Dilworth

    2013-06-01T23:59:59.000Z

    Employing a coded aperture pattern in front of a charge couple device pixilated detector (CCD) allows for imaging of fluorescent x-rays (6-25KeV) being emitted from samples irradiated with x-rays. Coded apertures encode the angular direction of x-rays and allow for a large Numerical Aperture x- ray imaging system. The algorithm to develop the self-supported coded aperture pattern of the Non Two Holes Touching (NTHT) pattern was developed. The algorithms to reconstruct the x-ray image from the encoded pattern recorded were developed by means of modeling and confirmed by experiments. Samples were irradiated by monochromatic synchrotron x-ray radiation, and fluorescent x-rays from several different test metal samples were imaged through the newly developed coded aperture imaging system. By choice of the exciting energy the different metals were speciated.

  16. Fluorescence quenching of CdSe quantum dots on graphene

    SciTech Connect (OSTI)

    Guo, Xi Tao; Hua Ni, Zhen, E-mail: zhni@seu.edu.cn; Yan Nan, Hai; Hui Wang, Wen [Department of Physics and Key Laboratory of MEMS of the Ministry of Education, Southeast University, Nanjing 211189 (China)] [Department of Physics and Key Laboratory of MEMS of the Ministry of Education, Southeast University, Nanjing 211189 (China); Yan Liao, Chun [Physics Department, National Photoelectric Technology and Functional Materials and Application of Science and Technology International Cooperation Base, Northwest University, Xi'an 710069 (China)] [Physics Department, National Photoelectric Technology and Functional Materials and Application of Science and Technology International Cooperation Base, Northwest University, Xi'an 710069 (China); Zhang, Yan; Wei Zhao, Wei [Jiangsu Key Laboratory for Design and Fabrication of Micro-Nano Biomedical Instruments, School of Mechanical Engineering, Southeast University, Nanjing 211189 (China)] [Jiangsu Key Laboratory for Design and Fabrication of Micro-Nano Biomedical Instruments, School of Mechanical Engineering, Southeast University, Nanjing 211189 (China)

    2013-11-11T23:59:59.000Z

    We studied systematically the fluorescence quenching of CdSe quantum dots (QDs) on graphene and its multilayers, as well as graphene oxide (GO) and reduced graphene oxide (rGO). Raman intensity of QDs was used as a quantitatively measurement of its concentration in order to achieve a reliable quenching factor (QF). It was found that the QF of graphene (?13.1) and its multilayers is much larger than rGO (?4.4), while GO (?1.5) has the lowest quenching efficiency, which suggests that the graphitic structure is an important factor for quenching the fluorescence of QDs. It was also revealed that the QF of graphene is not strongly dependent on its thicknesses.

  17. Archaeometrical studies using X-ray fluorescence methods

    SciTech Connect (OSTI)

    Pauna, Catalina; Constantinescu, B.; Constantin, F.; Bugoi, R.; Stan, D.; Vasilescu, A. [National Institute of Nuclear Physics and Engineering, POB MG-6, 077125, Bucharest (Romania)

    2010-04-26T23:59:59.000Z

    Elemental analysis contributes to authentication (knowing the elemental composition and considering the information about the usual composition of the objects in different historical periods it can be established if the item is original or fake), provenance studies (minor and trace elements indicates ores origin and 'consequently' mines location), (relative) dating of archaeological objects (e.g. for painted items--the chemical recipes for pigments can offer information about the age of objects). The paper gives a general layout for the NIPNE Archaeometry Laboratory's applications using X-Ray Fluorescence (XRF), micro--Proton Induced X-Ray Emission (micro-PIXE), micro-Synchrotron Radiation Induced X-Ray Fluorescence (micro--SR-XRF) methods.

  18. Noise induced narrowing of metamolecule fluorescence spectral line

    E-Print Network [OSTI]

    E. S. Andrianov; N. M. Chtchelkatchev; A. A. Pukhov

    2015-04-27T23:59:59.000Z

    We consider metamolecule consisting of bosonic mode correlated with the two-level system: it can be, for example, plasmonic mode interacting with the quantum dot or molecule in the resonator. We focus on the parameter range where all the correlations are strong and of the same order: interaction between bosonic mode correlated with the two-level system, external coherent drive and dissipation. Quantum Monte-Carlo simulations show a fluorescence of this system at dissipation larger than the driving amplitude and strong (by the order of magnitude) narrowing of its spectral line. This effect may be related to kind of a quantum stochastic resonance. We show that the fluorescence corresponds to finite domain over the coherent drive with sharp lower threshold and there is splitting of the Wigner function.

  19. DNA fragment sizing and sorting by laser-induced fluorescence

    DOE Patents [OSTI]

    Hammond, Mark L. (Angier, NC); Jett, James H. (Los Alamos, NM); Keller, Richard A. (Los Alamos, NM); Marrone, Babetta L. (Los Alamos, NM); Martin, John C. (Los Alamos, NM)

    1996-01-01T23:59:59.000Z

    A method is provided for sizing DNA fragments using high speed detection systems, such as flow cytometry to determine unique characteristics of DNA pieces from a sample. In one characterization the DNA piece is fragmented at preselected sites to produce a plurality of DNA fragments. The DNA piece or the resulting DNA fragments are treated with a dye effective to stain stoichiometrically the DNA piece or the DNA fragments. The fluorescence from the dye in the stained fragments is then examined to generate an output functionally related to the number of nucleotides in each one of the DNA fragments. In one embodiment, the intensity of the fluorescence emissions from each fragment is linearly related to the fragment length. The distribution of DNA fragment sizes forms a characterization of the DNA piece for use in forensic and research applications.

  20. Rotational order–disorder structure of fluorescent protein FP480

    SciTech Connect (OSTI)

    Pletnev, Sergei, E-mail: svp@ncifcrf.gov [SAIC-Frederick Inc., Basic Research Program, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States); Morozova, Kateryna S.; Verkhusha, Vladislav V. [Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York 10461 (United States); Dauter, Zbigniew, E-mail: svp@ncifcrf.gov [Synchrotron Radiation Research Section, MCL, National Cancer Institute, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States); SAIC-Frederick Inc., Basic Research Program, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States)

    2009-09-01T23:59:59.000Z

    An analysis of the rotational order–disorder structure of fluorescent protein FP480 is presented. In the last decade, advances in instrumentation and software development have made crystallography a powerful tool in structural biology. Using this method, structural information can now be acquired from pathological crystals that would have been abandoned in earlier times. In this paper, the order–disorder (OD) structure of fluorescent protein FP480 is discussed. The structure is composed of tetramers with 222 symmetry incorporated into the lattice in two different ways, namely rotated 90° with respect to each other around the crystal c axis, with tetramer axes coincident with crystallographic twofold axes. The random distribution of alternatively oriented tetramers in the crystal creates a rotational OD structure with statistically averaged I422 symmetry, although the presence of very weak and diffuse additional reflections suggests that the randomness is only approximate.

  1. COMBINED FLUORESCENT AND GOLD PROBES FOR MICROSCOPIC AND MORPHOLOGICAL INVESTIGATIONS.

    SciTech Connect (OSTI)

    POWELL,R.D.HAINFELD,J.F.

    2002-04-17T23:59:59.000Z

    Nanogold{reg_sign}, a gold cluster with a core of gold atoms 1.4 nm in diameter, has proven to be a superior probe label for electron microscopy (EM), giving both higher labeling density and improved access to previously hindered or restricted antigens. It may be visualized by autometallography (AMG) for use in light microscopy (LM): silver-and gold-amplified Nanogold detection has proven to be one of the most sensitive methods available for the detection of low copy number targets such as viral DNA in cells and tissue specimens. AMG enhancement has also made Nanogold an effective detection label in blots and gels. The following protocols will be described: Labeling of nuclear components in cells. Protocol for in situ hybridization and detection with fluorescein-Nanogold--or Cy3{trademark}-Nanogold-labeled streptavidin. Nanogold is an inert molecule, and generally does not interact with biological molecules unless a specific chemical reactivity is introduced into the molecule. Conjugates are prepared using site-specific chemical conjugation through reactive chemical functionalities introduced during Nanogold preparation, which allows the gold label to be attached to a specific site on the conjugate biomolecule. For example, a maleimido-Nanogold derivative, which is specific for thiol binding, is frequently attached to the hinge region of an antibody at a unique thiol site generated by selective reduction of a hinge disulfide. This site is remote from the antigen combining region, and the Nanogold, therefore, does not compromise target binding. Nanogold may also be prepared with specific reactivity towards amines or other unique chemical groups. This mode of attachment enables the preparation of probes labeled with both Nanogold and fluorescent labels. Different chemical reactivities are used to attach the Nanogold and the fluorescent groups to different sites in the conjugate biomolecule, as shown in Figure 7.1. In this manner, the two labels are spaced sufficiently far apart that fluorescent resonance energy transfer does not quench the fluorescent signal, and the probes may be used to label specimens for fluorescent and EM observation in a single staining procedure. This reduces the complexity of the staining procedure, allowing less specimen perturbation, and also enables a higher degree of correlation between the fluorescence and EM localization of the target, thus increasing the usefulness of the complementary data sets. Since gold and fluorescent-labeled probes are often used at different concentrations under different conditions, optimum procedures for the use of fluorescent and gold probes may entail some degree of compromise between the most appropriate conditions for the two types of probes. However, the chemical stability of the Nanogold label means that it is generally stable to a wide range of use conditions, and the following protocols have been found to be effective for labeling specimens with combined fluorescein and Nanogold-labeled antibody Fab' probes and with combined Cy3 and Nanogold-labeled streptavidin.

  2. Development of a fluorescent antibody test for equine infectious anemia

    E-Print Network [OSTI]

    Lester, Thomas Lee

    1972-01-01T23:59:59.000Z

    . Moore The development of a direct fluorescent antibody technique for a reliable laboratory and diagnostic test for equine infectious anemia (EIA) was described. A specific antiserum was produced by inoculation of goats with EIA virus derived from... the Texas and Illinois strains of EIA virus in cell culture and in known infected horses and against the Wyoming strain of EIA virus in inoculated horses. Its specificity was further substantiated by testing it against heterologous viruses including...

  3. Contraband Detection with Nuclear Resonance Fluorescence: Feasibility and Impact

    SciTech Connect (OSTI)

    Pruet, J; Lange, D

    2007-01-03T23:59:59.000Z

    In this report they show that cargo interrogation systems developed to thwart trafficking of illicit nuclear materials could also be powerful tools in the larger fight against contraband smuggling. In particular, in addition to detecting special nuclear materials, cargo scanning systems that exploit nuclear resonance fluorescence to detect specific isotopes can be used to help find: chemical weapons; some drugs as well as some chemicals regulated under the controlled substances act; precious metals; materials regulated under export control laws; and commonly trafficked fluorocarbons.

  4. Dynamic fluorescence imaging with molecular agents for cancer detection

    E-Print Network [OSTI]

    Kwon, Sun Kuk

    2009-05-15T23:59:59.000Z

    emission computed tomography SUV standard uptake values SLN sentinel lymph node TK tyrosine kinase TBR target to background ratio Symbols ? pharmacokinetic parameter ? pharmacokinetic parameter )(tC BOUND concentration of dye... bound to integrin receptor either in the vascular or extravascular compartments )(tC LAREXTRAVASCU concentration of dye in extravascular space )(tC VASCULAR concentration of dye in vascular space 0 I background fluorescence intensity c k...

  5. Nuclear Resonance Fluorescence and Isotopic Mapping of Containers

    SciTech Connect (OSTI)

    Johnson, M S; McNabb, D P

    2008-08-08T23:59:59.000Z

    National security programs have expressed interest in developing systems to isotopically map shipping containers, fuel assemblies, and waste barrels for various materials including special nuclear material (SNM). Current radiographic systems offer little more than an ambiguous density silhouette of a container's contents. In this paper we will present a system being developed at LLNL to isotopically map containers using the nuclear resonance fluorescence (NRF) method. Recent experimental measurements on NRF strengths in SNM are discussed.

  6. Magnetic fluorescent lamp having reduced ultraviolet self-absorption

    DOE Patents [OSTI]

    Berman, Samuel M. (San Francisco, CA); Richardson, Robert W. (Pelham, NY)

    1985-01-01T23:59:59.000Z

    The radiant emission of a mercury-argon discharge in a fluorescent lamp assembly (10) is enhanced by providing means (30) for establishing a magnetic field with lines of force along the path of electron flow through the bulb (12) of the lamp assembly, to provide Zeeman splitting of the ultraviolet spectral line. Optimum results are obtained when the magnetic field strength causes a Zeeman splitting of approximately 1.7 times the thermal line width.

  7. Enhanced detection of fluorescence quenching in labeled cells

    DOE Patents [OSTI]

    Crissman, H.A.; Steinkamp, J.A.

    1987-11-30T23:59:59.000Z

    A method is provided for quantifying BrdU labeled DNA in cells. The BrdU is substituted onto the DNA and the DNA is stained with a first fluorochrome having a fluorescence which is quenchable by BrdU. The first fluorochrome is preferably a thymidine base halogen analogue, such as a Hoechst fluorochrome. The DNA is then stained with a second fluorochrome having a fluorescence which is substantially uneffected by BrdU. The second fluorochrome may be selected from the group consisting of mithramycin, chromomycin A3, olivomycin, propidium iodide and ethidium bromine. The fluorescence from the first and second fluorochromes is then measured to obtain first and second output signals, respectively. The first output signal is subtracted from the second output signal to obtain a difference signal which is functionally related to the quantity of BrdU incorporated into DNA. The technique is particularly useful for quantifying the synthesis of DNA during the S-phase of the cell cycle. 2 figs.

  8. ISSUANCE 2014-12-29: Energy Conservation Program: Clarification for Energy Conservation Standards and Test Procedures for Fluorescent Lamp Ballasts

    Broader source: Energy.gov [DOE]

    Energy Conservation Program: Clarification for Energy Conservation Standards and Test Procedures for Fluorescent Lamp Ballasts

  9. Zero energy-storage ballast for compact fluorescent lamps

    DOE Patents [OSTI]

    Schultz, William Newell (Niskayuna, NY); Thomas, Robert James (Rexford, NY)

    1999-01-01T23:59:59.000Z

    A CFL ballast includes complementary-type switching devices connected in series with their gates connected together at a control node. The switching devices supply a resonant tank circuit which is tuned to a frequency near, but slightly lower than, the resonant frequency of a resonant control circuit. As a result, the tank circuit restarts oscillations immediately following each zero crossing of the bus voltage. Such rapid restarts avoid undesirable flickering while maintaining the operational advantages and high efficacy of the CFL ballast.

  10. Characterization of dissolved organic matter fluorescence in the South Atlantic Bight with use of PARAFAC model: Relationships between fluorescence and its

    E-Print Network [OSTI]

    Durako, Michael J.

    [aCDOM(350)] and CDOM excitation emission matrix (EEM) fluorescence were used to estimate annual (PARAFAC) of CDOM EEM spectra identified six components: three terrestrial humic-like, one marine humic concentration and aCDOM(350), total fluorescence intensity and the intensities of respective EEM components. DOC

  11. The Hazards of Use and Disposal of Compact Fluorescent Bulbs Compact fluorescent lights (aka. CFLs) work by exciting a phosphorous coating within the tube to emit

    E-Print Network [OSTI]

    Maroncelli, Mark

    The Hazards of Use and Disposal of Compact Fluorescent Bulbs Compact fluorescent lights (aka. CFLs the bulb to be an efficient light source. By comparison, older home thermometers contain 500 milligrams decade. HOW SHOULD I DISPOSE OF CFL'S? The presence of mercury requires that all CFL bulbs are properly

  12. arthritis forty-eight-week efficacy: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    poor localities influence the capacity for community efficacy. Through a multivariate analysis using 497 households in poor localities of Addis Ababa, we investigate how social...

  13. assessor-blind comparative efficacy: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    variations in poor localities influence the capacity for community efficacy. Through a multivariate analysis using 497 households in poor localities of Addis Ababa, we...

  14. Mechanisms of NDV-3 vaccine efficacy in MRSA skin versus invasive infection

    E-Print Network [OSTI]

    2014-01-01T23:59:59.000Z

    3 vaccine efficacy in MRSA skin versus invasive infectionFig. 1) and suppression of MRSA proliferation (Fig. 2). Eachseverity and suppression of MRSA bioluminescence (Figs. 1

  15. A light diet for a giant appetite: An assessment of China's proposed fluorescent lamp standard

    SciTech Connect (OSTI)

    Lin, Jiang

    2002-04-11T23:59:59.000Z

    Lighting has been one of the fastest growing electric end-uses in China over the last twenty years, with an average annual growth rate of 14%. Fluorescent lighting provides a significant portion of China's lighting need. In 1998, China produced 680 million fluorescent lamps, of which 420 million were linear fluorescent lamps of various diameters (T8 to T12). There are substantial variations both in energy efficiency and lighting performance among locally produced fluorescent lamps. Such variations present a perfect opportunity for policy intervention through efficiency standards to promote the adoption of more efficient fluorescent lamps in China. This paper analyzes China's proposed minimum efficiency standard for fluorescent lamps and presents an assessment of its likely impacts on China's lighting energy consumption and GHG emissions.

  16. Air Fluorescence Relevant for Cosmic-Ray Detection - Review of Pioneering Measurements

    E-Print Network [OSTI]

    Fernando Arqueros; Joerg R. Hoerandel; Bianca Keilhauer

    2008-07-24T23:59:59.000Z

    Cosmic rays with energies exceeding $10^{17}$ eV are frequently registered by measurements of the fluorescence light emitted by extensive air showers. The main uncertainty for the absolute energy scale of the measured air showers is coming from the fluorescence light yield of electrons in air. The fluorescence light yield has been studied in laboratory experiments. Pioneering measurements between 1954 and 2000 are reviewed.

  17. Microcavity effects on the generation,fluorescence, and diffusion of excitons in organic solar cells

    E-Print Network [OSTI]

    Kozyreff, G; Vuong, L T; Silleras, O Nieto; Martorell, J

    2013-01-01T23:59:59.000Z

    We compute the short-circuit diffusion current of excitons in an organic solar cell, with special emphasis on fluorescence losses. The exciton diffusion length is not uniform but varies with its position within the device, even with moderate fluorescence quantum efficiency. With large quantum efficiencies, the rate of fluorescence can be strongly reduced with proper choices of the geometrical and dielectric parameters. In this way, the diffusion length can be increased and the device performance significantly improved.

  18. Feedback control of the squeezing of the fluorescence light

    E-Print Network [OSTI]

    Alberto Barchielli; Matteo Gregoratti

    2009-10-09T23:59:59.000Z

    Among the formulations of the theory of quantum measurements in continuous time, quantum trajectory theory is very suitable for the introduction of measurement based feedback and closed loop control of quantum systems. In this paper we present such a construction in the concrete case of a two-level atom stimulated by a coherent, monochromatic laser. In particular, we show how fast feedback \\`a la Wiseman and Milburn can be introduced in the formulation of the theory. Then, the spectrum of the free fluorescence light is studied and typical quantum phenomena, squeezing and sub-natural line-narrowing, are presented.

  19. Quantum Process Tomography by 2D Fluorescence Spectroscopy

    E-Print Network [OSTI]

    Leonardo A. Pachon; Andrew H. Marcus; Alan Aspuru-Guzik

    2015-02-09T23:59:59.000Z

    Reconstruction of the dynamics (quantum process tomography) of the single-exciton manifold in energy transfer systems is proposed here on the basis of two-dimensional fluorescence spectroscopy (2D-FS) with phase-modulation. The quantum-process-tomography protocol introduced here benefits from, e.g., the sensitivity enhancement and signal-to-noise ratio ascribed to 2D-FS. Although the isotropically averaged spectroscopic signals depend on the quantum yield parameter $\\Gamma$ of the doubly-excited-exciton manifold, it is shown that the reconstruction of the dynamics is insensitive to this parameter. Applications to foundational and applied problems, as well as further extensions, are discussed.

  20. Quantum Process Tomography by 2D Fluorescence Spectroscopy

    E-Print Network [OSTI]

    Pachon, Leonardo A; Aspuru-Guzik, Alan

    2015-01-01T23:59:59.000Z

    Reconstruction of the dynamics (quantum process tomography) of the single-exciton manifold in energy transfer systems is proposed here on the basis of two-dimensional fluorescence spectroscopy (2D-FS) with phase-modulation. The quantum-process-tomography protocol introduced here benefits from, e.g., the sensitivity enhancement and signal-to-noise ratio ascribed to 2D-FS. Although the isotropically averaged spectroscopic signals depend on the quantum yield parameter $\\Gamma$ of the doubly-excited-exciton manifold, it is shown that the reconstruction of the dynamics is insensitive to this parameter. Applications to foundational and applied problems, as well as further extensions, are discussed.

  1. Interaction of fluorescent probes with dodecylammonium propionate aggregates in cyclohexane

    E-Print Network [OSTI]

    Correll, Glenn David

    1975-01-01T23:59:59.000Z

    of Added . 01M NaOEL 44 48 51 54 25. Rate P1ot of Carbontetrachloride Quenching of PSA in DAP/Cyclohexane. 26. Rate Plots of KSr Quenching of PSA. in DAP/Cyclohexane 58 at Different Stoichiometric Concentrations of Hs0. . . . . 61 27. KBr... Quenching Rate vs. Aqueous Volume. . . . . . . . . . . . . 28. PSA Fluorescence Lifetimes vs. Aqueous Volume of Constant KBr Concentration (4. OM KBr/0. 01M NaOH). . . 29. Plot of' ?. /(I- ?. ) vs. [DAP] for PSA in Cyclohexane at Constant Water...

  2. Blue-green phosphor for fluorescent lighting applications

    DOE Patents [OSTI]

    Srivastava, Alok; Comanzo, Holly; Manivannan, Venkatesan; Setlur, Anant Achyut

    2005-03-15T23:59:59.000Z

    A fluorescent lamp including a phosphor layer including Sr.sub.4 Al.sub.14 O.sub.25 :Eu.sup.2+ (SAE) and at least one of each of a red, green and blue emitting phosphor. The phosphor layer can optionally include an additional, deep red phosphor and a yellow emitting phosphor. The resulting lamp will exhibit a white light having a color rendering index of 90 or higher with a correlated color temperature of from 2500 to 10000 Kelvin. The use of SAE in phosphor blends of lamps results in high CRI light sources with increased stability and acceptable lumen maintenance over, the course of the lamp life.

  3. Product Standards for Fluorescent Lighting (Japan) | Open Energy

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to: navigation,Pillar Group BV Jump to: navigation,PowerInformation Fluorescent Lighting

  4. EA-1881: Energy Conservation Program: Energy Conservation Standards for Fluorescent Lamp Ballasts

    Broader source: Energy.gov [DOE]

    This EA evaluates the environmental impacts of a proposal to amend energy conservation standards for various consumer products and certain commercial and industrial equipment, including fluorescent lamp ballasts.

  5. High power light emitting diode based setup for photobleaching fluorescent impurities

    E-Print Network [OSTI]

    Kaufman, Laura

    High power light emitting diode based setup for photobleaching fluorescent impurities Tobias K be photobleached before final sample preparation. The instrument consists of high power light emitting diodes

  6. Nuclear Resonance Fluorescence to Measure Plutonium Mass in Spent Nuclear Fuel

    E-Print Network [OSTI]

    Ludewigt, Bernhard A

    2011-01-01T23:59:59.000Z

    and Nuclear Recoil . . . . . . . . . . . . . . . . . . . . .2 Quantitative Measurements using NRF 2.1 Nuclear ResonanceFuture Work A Transmission Nuclear Resonance Fluorescence

  7. Volume 20. number 3 FEBS LETTERS February 1972 FLUORESCENCE AND DELAYED LIGHT EMISSION IN

    E-Print Network [OSTI]

    Govindjee

    : dichloroplenol indophenol; DLE: delayed light emission; NADP+: nicotinamide adenine dinucleotide phosphate; PDA (DLE) that of Jursinic and Govindjee [4]. For mea- surements of the recovery of fluorescence transients

  8. Graphene Signal Amplification for Sensitive and Real-Time Fluorescence Anisotropy Detection of Small Molecules

    E-Print Network [OSTI]

    Tan, Weihong

    Graphene Signal Amplification for Sensitive and Real-Time Fluorescence Anisotropy Detection graphene oxide (GO) as the signal amplifier. Because of the extraordinarily larger volume of GO

  9. Fluorescent properties of c-type cytochromes reveal their potential role as an extracytoplasmic electron

    E-Print Network [OSTI]

    Lovley, Derek

    via fluorescence microscopy, and the cyto- chromes in a G. sulfurreducens biofilm, remotely excited communities have indi- cated that Geobacter species are the predominant metal-reducing microorganisms

  10. Excitation-emission spectra and fluorescence quantum yields for fresh and aged biogenic secondary organic aerosols

    SciTech Connect (OSTI)

    Lee, Hyun Ji; Laskin, Alexander; Laskin, Julia; Nizkorodov, Sergey A.

    2013-05-10T23:59:59.000Z

    Certain biogenic secondary organic aerosols (SOA) become absorbent and fluorescent when exposed to reduced nitrogen compounds such as ammonia, amines and their salts. Fluorescent SOA may potentially be mistaken for biological particles by detection methods relying on fluorescence. This work quantifies the spectral distribution and effective quantum yields of fluorescence of SOA generated from two monoterpenes, limonene and a-pinene, and two different oxidants, ozone (O3) and hydroxyl radical (OH). The SOA was generated in a smog chamber, collected on substrates, and aged by exposure to ~100 ppb ammonia vapor in air saturated with water vapor. Absorption and excitation-emission matrix (EEM) spectra of aqueous extracts of aged and control SOA samples were measured, and the effective absorption coefficients and fluorescence quantum yields (~0.005 for 349 nm excitation) were determined from the data. The strongest fluorescence for the limonene-derived SOA was observed for excitation = 420+- 50 nm and emission = 475 +- 38 nm. The window of the strongest fluorescence shifted to excitation = 320 +- 25 nm and emission = 425 +- 38 nm for the a-pinene-derived SOA. Both regions overlap with the excitation-emission matrix (EEM) spectra of some of the fluorophores found in primary biological aerosols. Our study suggests that, despite the low quantum yield, the aged SOA particles should have sufficient fluorescence intensities to interfere with the fluorescence detection of common bioaerosols.

  11. Capillary electrophoresis-fluorescence line narrowing system (CE-FLNS) for on-line structural characterization

    DOE Patents [OSTI]

    Jankowiak, R.J.; Small, G.J.; Shields, P.A.

    1999-04-27T23:59:59.000Z

    Capillary electrophoresis (CE) is interfaced with low temperature fluorescence line-narrowing (FLN) spectroscopy for on-line structural characterization of separated molecular analytes. 21 figs.

  12. Capillary electrophoresis-fluorescence line narrowing system (CE-FLNS) for on-line structural characterization

    DOE Patents [OSTI]

    Jankowiak, Ryszard J. (Ames, IA); Small, Gerald J. (Ames, IA); Shields, Peter A. (Reading, MA)

    1999-04-27T23:59:59.000Z

    Capillary electrophoresis (CE) is interfaced with low temperature fluorescence line-narrowing (FLN) spectroscopy for on-line structural characterization of separated molecular analytes.

  13. AUTOMATED ELEMENTAL ANALYSIS USING ENERGY DISPERSIVE X-RAY FLUORESCENCE ANALYSIS

    E-Print Network [OSTI]

    Jaklevic, J.M.

    2011-01-01T23:59:59.000Z

    upon the x-ray fluorescence (XRF) method for the elementalnon-destructive nature of XRF is especially important whereconcentrations are measured in the XRF spectrometer and the

  14. Coral fluorescence and symbiosis : photoacclimation, thermal shock, life history changes, and implications for reef monitoring

    E-Print Network [OSTI]

    Roth, Melissa Susan

    2010-01-01T23:59:59.000Z

    Diversity and evolution of coral fluorescent proteins. PLoSB. (2008). Climate change and coral reef bleaching: Anpigment in reef-building corals. Mar. Ecol. Prog. Ser. 364,

  15. Fluorescence-based detection methodologies for nitric oxide using transition metal scaffolds

    E-Print Network [OSTI]

    Hilderbrand, Scott A. (Scott Alan), 1976-

    2004-01-01T23:59:59.000Z

    Chapter 1. Fluorescence-Based Detection Methodologies for Nitric Oxide: A Review. Chapter 2. Cobalt Chemistry with Mixed Aminotroponimine Salicylaldimine Ligands: Synthesis, Characterization, and Nitric Oxide Reactivity. ...

  16. Lung Cancer (2005) 47, 41--47 Improving the specificity of fluorescence

    E-Print Network [OSTI]

    Duin, Robert P.W.

    2005-01-01T23:59:59.000Z

    Lung Cancer (2005) 47, 41--47 Improving the specificity of fluorescence bronchoscopy spectroscopy; Lung cancer; Bronchoscopy Summary Detection of malignancies of the bronchial tree in an early

  17. Fluorescence spectrum analysis using Fourier series modeling for Fluorescein solution in Ethanol

    E-Print Network [OSTI]

    Hadi, Mahasin F

    2011-01-01T23:59:59.000Z

    We have measured the fluorescence spectrum for fluorescein solution in ethanol with concentration 1 {\\times} 10-3 mol/liter at different temperatures from room temperature to freezing point of solvent, (T = 153, 183, 223, 253, and 303 K) using liquid nitrogen. Table curve 2D version 5.01 program has been used to determine the fitting curve and fitting equation for each fluorescence spectrum. Fourier series (3 {\\times} 2) was the most suitable fitting equation for all spectra. Theoretical fluorescence spectrum of fluorescein in ethanol at T = 183K was calculated and compared with experimental fluorescence spectrum at the same temperature. There is a good similarity between them.

  18. Development of High Efficacy, Low Cost Phosphorescent Oled Lightning Luminaire

    SciTech Connect (OSTI)

    Michael Hack

    2010-07-09T23:59:59.000Z

    In this two year program, UDC together with Armstrong World Industries, Professor Stephen Forrest (University of Michigan) and Professor Mark Thompson (University of Southern California) planned to develop and deliver high efficiency OLED lighting luminaires as part of an integrated ceiling illumination system that exceed the Department of Energy (DOE) 2010 performance projections. Specifically the UDC team in 2010 delivered two prototype OLED ceiling illumination systems, each consisting of four individual OLED lighting panels on glass integrated into Armstrong's novel TechZone open architecture ceiling systems, at an overall system efficacy of 51 lm/W, a CRI = 85 and a projected lifetime to 70% of initial luminance to exceed 10,000 hours. This accomplishment represents a 50% increase in luminaire efficacy and a factor of two in lifetime over that outlined in the solicitation. In addition, the team has also delivered one 15cm x 15cm lighting panel fabricated on a flexible metal foil substrate, demonstrating the possibility using OLEDs in a range of form factors. During this program, our Team has pursued the commercialization of these OLED based ceiling luminaires, with a goal to launch commercial products within the next three years. We have proven that our team is ideally suited to develop these highly novel and efficient solid state lighting luminaires, having both the technical experience and commercial strategy to leverage work performed under this contract. Our calculations show that the success of our program could lead to energy savings of more than 0.5 quads or 8 MMTC (million metric tons of carbon) per year by 2016.

  19. Zero energy-storage ballast for compact fluorescent lamps

    DOE Patents [OSTI]

    Schultz, W.N.; Thomas, R.J.

    1999-08-31T23:59:59.000Z

    A CFL ballast includes complementary-type switching devices connected in series with their gates connected together at a control node. The switching devices supply a resonant tank circuit which is tuned to a frequency near, but slightly lower than, the resonant frequency of a resonant control circuit. As a result, the tank circuit restarts oscillations immediately following each zero crossing of the bus voltage. Such rapid restarts avoid undesirable flickering while maintaining the operational advantages and high efficacy of the CFL ballast. 4 figs.

  20. A Highly Efficacious Lymphocyte Chemoattractant, Stromal Cell-derived Factor 1 (SDF-1)

    E-Print Network [OSTI]

    Springer, Timothy A.

    A Highly Efficacious Lymphocyte Chemoattractant, Stromal Cell-derived Factor 1 (SDF-1) By Conrad C-derived factor 1 (SDF-1). SDF-1 acts on lymphocytes and monocytes but not neutrophils in vitro and is both a highly efficacious and highly potent mononuclear cell attractant in vivo. In addition, SDF-1 induces

  1. Protein- protein interaction detection system using fluorescent protein microdomains

    DOE Patents [OSTI]

    Waldo, Geoffrey S. (Santa Fe, NM); Cabantous, Stephanie (Los Alamos, NM)

    2010-02-23T23:59:59.000Z

    The invention provides a protein labeling and interaction detection system based on engineered fragments of fluorescent and chromophoric proteins that require fused interacting polypeptides to drive the association of the fragments, and further are soluble and stable, and do not change the solubility of polypeptides to which they are fused. In one embodiment, a test protein X is fused to a sixteen amino acid fragment of GFP (.beta.-strand 10, amino acids 198-214), engineered to not perturb fusion protein solubility. A second test protein Y is fused to a sixteen amino acid fragment of GFP (.beta.-strand 11, amino acids 215-230), engineered to not perturb fusion protein solubility. When X and Y interact, they bring the GFP strands into proximity, and are detected by complementation with a third GFP fragment consisting of GFP amino acids 1-198 (strands 1-9). When GFP strands 10 and 11 are held together by interaction of protein X and Y, they spontaneous association with GFP strands 1-9, resulting in structural complementation, folding, and concomitant GFP fluorescence.

  2. Red phosphors for use in high CRI fluorescent lamps

    DOE Patents [OSTI]

    Srivastava, Alok; Comanzo, Holly; Manivannan, Vankatesan; Setlur, Anant Achyut

    2005-11-15T23:59:59.000Z

    Novel red emitting phosphors for use in fluorescent lamps resulting in superior color rendering index values compared to conventional red phosphors. Also disclosed is a fluorescent lamp including a phosphor layer comprising blends of one or more of a blue phosphor, a blue-green phosphor, a green phosphor and a red a phosphor selected from the group consisting of SrY.sub.2 O.sub.4 :Eu.sup.3+, (Y,Gd)Al.sub.3 B.sub.4 O.sub.12 :Eu.sup.3+, and [(Y.sub.1-x-y-m La.sub.y)Gd.sub.x ]BO.sub.3 :Eu.sub.m wherein y<0.50 and m=0.001-0.3. The phosphor layer can optionally include an additional deep red phosphor and a yellow emitting phosphor. The resulting lamp will exhibit a white light having a color rendering index of 90 or higher with a correlated color temperature of from 2500 to 10000 Kelvin. The use of the disclosed red phosphors in phosphor blends of lamps results in high CRI light sources with increased stability and acceptable lumen maintenance over the course of the lamp life.

  3. Measuring the Efficacy of Leaders to Assess Information and Make Decisions in a Crisis: The C-LEAD Scale

    E-Print Network [OSTI]

    Pittinsky, Todd L.

    2009-07-01T23:59:59.000Z

    Based on literature and expert interviews, we developed the Crisis Leader Efficacy in Assessing and Deciding scale (C-LEAD) to capture the efficacy of leaders to assess information and make decisions in a public health and ...

  4. Synthesis and Characterization of Novel Fluorescent Injectable Micro-Carriers for Tissue Regeneration 

    E-Print Network [OSTI]

    Arora, Akshi

    2014-04-28T23:59:59.000Z

    of sacrificing the animals or undertaking elaborate histological procedures. To date, there is no report on the synthesis of fluorescent PLLA. In this research, we aim to develop an injectable fluorescent PLLA scaffold for tissue regeneration by using Eosin Y (EY...

  5. FISH and Chips: Automation of Fluorescent Dot Counting in Interphase Cell Nuclei

    E-Print Network [OSTI]

    van Vliet, Lucas J.

    ) in each cell nucleus. This system works with two fluorescent dyes, one for the DNA hybridization dotsFISH and Chips: Automation of Fluorescent Dot Counting in Interphase Cell Nuclei Hans Netten,1 Ian abnormalities in inter- phase cell nuclei. This process is called dot counting. To estimate the distribution

  6. Demonstration of Fluorescent RGB Electrowetting Devices for Light Wave Coupling Displays

    E-Print Network [OSTI]

    Steckl, Andrew J.

    and wasted, instead of recycling the light for use at pixels in the ON state. We present the demonstration-degrade the organic fluorescent oils. Violet light sources include custom developed cold-cathode- fluorescent lamps of a traditional diffuse backlight because (as will be discussed later) it allows for the advantage of recycling

  7. A Behavioral SPICE Compatible Model of an Electrodeless Fluorescent Lamp Sam Ben-Yaakov*1

    E-Print Network [OSTI]

    to the plasma. In the case of the lamp with electrodes, coupling is via wires. In the case of the electrodelessA Behavioral SPICE Compatible Model of an Electrodeless Fluorescent Lamp Sam Ben-Yaakov*1 , Moshe, SPICE compatible, model was developed for an electrodeless fluorescent lamp (OSRAM SYLVANIA ICETRON

  8. Nucleic acid encoding a self-assembling split-fluorescent protein system

    DOE Patents [OSTI]

    Waldo, Geoffrey S; Cabantous, Stephanie

    2014-04-01T23:59:59.000Z

    The invention provides a protein labeling and detection system based on self-complementing fragments of fluorescent and chromophoric proteins. The system of the invention is exemplified with various combinations of self-complementing fragments derived from Aequorea victoria Green Fluorescent Protein (GFP), which are used to detect and quantify protein solubility in multiple assay formats, both in vitro and in vivo.

  9. Directed evolution methods for improving polypeptide folding and solubility and superfolder fluorescent proteins generated thereby

    DOE Patents [OSTI]

    Waldo, Geoffrey S. (Santa Fe, NM)

    2007-09-18T23:59:59.000Z

    The current invention provides methods of improving folding of polypeptides using a poorly folding domain as a component of a fusion protein comprising the poorly folding domain and a polypeptide of interest to be improved. The invention also provides novel green fluorescent proteins (GFPs) and red fluorescent proteins that have enhanced folding properties.

  10. Nucleic acid encoding a self-assembling split-fluorescent protein system

    DOE Patents [OSTI]

    Waldo, Geoffrey S. (Santa Fe, NM); Cabantous, Stephanie (Los Alamos, NM)

    2011-06-07T23:59:59.000Z

    The invention provides a protein labeling and detection system based on self-complementing fragments of fluorescent and chromophoric proteins. The system of the invention is exemplified with various combinations of self-complementing fragments derived from Aequorea victoria Green Fluorescent Protein (GFP), which are used to detect and quantify protein solubility in multiple assay formats, both in vitro and in vivo.

  11. [16) Green Fluorescent Protein Chimeras to Probe Protein-Protein Interactions

    E-Print Network [OSTI]

    Raines, Ronald T.

    [16) Green Fluorescent Protein Chimeras to Probe Protein-Protein Interactions By SANG-HYUN PARK of reproduction in any form reserved. 0076-6879/00 $30.00 #12;252 A B OTHER APPROACHES USING CHIMERAS c ~S65T GFPHDII M 66 .......... 4S,.!;. 31 ui' 14 ..... [lB) FIG. 1. Green fluorescent protein chimera. (A

  12. Fluorescence Assay 2. http://www.tgrbio.com/cancer-cell-lines-primary-cell-

    E-Print Network [OSTI]

    Collins, Gary S.

    hazardous waste. Fluorescence microscopy is a powerful tool with a broad scope of applications easily fluorescence microscopy. In creating an innovative protocol for the 5-HT3a receptor, it is necessary-HT3a Expression Purification/Characterization While creating a protocol for protein expression

  13. Ultrafast Proton Shuttling in Psammocora Cyan Fluorescent Protein John T. M. Kennis,*,

    E-Print Network [OSTI]

    van Stokkum, Ivo

    Ultrafast Proton Shuttling in Psammocora Cyan Fluorescent Protein John T. M. Kennis,*, Ivo H. M-state proton transfer (ESPT) reactions. Recently, a novel cyan fluorescent protein (CFP) termed psamFP488 vicinity to the chromophore to act as a proton acceptor. Our findings support a model where unusually fast

  14. Transition in the Temperature-Dependence of GFP Fluorescence: From Proton Wires to Proton Exit

    E-Print Network [OSTI]

    Agmon, Noam

    Transition in the Temperature-Dependence of GFP Fluorescence: From Proton Wires to Proton Exit protein, photo-excitation leads to excited-state proton transfer from its chromophore, leaving behind a strongly fluorescing anion, while the proton is commonly thought to migrate internally to Glu-222. X

  15. Fluorescence diagnostics of oil pollution in coastal marine waters by use of artificial neural networks

    E-Print Network [OSTI]

    Oldenburg, Carl von Ossietzky Universität

    marine waters with fluorescence spectroscopy and of using artificial neural networks for data interpre with an artificial neural network. The results demonstrate the possibility of estimating oil concentrationsFluorescence diagnostics of oil pollution in coastal marine waters by use of artificial neural

  16. Optical fiber-based fluorescent viscosity sensor Mark A. Haidekker and Walter J. Akers

    E-Print Network [OSTI]

    Theodorakis, Emmanuel

    Optical fiber-based fluorescent viscosity sensor Mark A. Haidekker and Walter J. Akers Department to molecular rotors in solution. An optical fiber-based fluorescent vis- cosity sensor may be used in real, we sought to develop an optical fiber-based sensor that could re- port changes in fluid viscosity

  17. Improving the photostability of bright monomeric orange and red fluorescent proteins

    E-Print Network [OSTI]

    Tsien, Roger Y.

    Improving the photostability of bright monomeric orange and red fluorescent proteins Nathan C illumination. Although fluorescent proteins typically bleach at a substantially slower rate than many small-molecule dyes, in many cases the lack of sufficient photostability remains an important limiting factor

  18. Micro-Raman Spectroscopy of Algae: Composition Analysis and Fluorescence Background Behavior

    E-Print Network [OSTI]

    ARTICLE Micro-Raman Spectroscopy of Algae: Composition Analysis and Fluorescence Background performed using Stokes Raman scattering for compositional analysis of algae. Two algal species, Chlorella while acquiring Raman signals from the algae. The time dependence of fluorescence background is char

  19. Volume 57, number 3 FEBS LETTERS October 1975 INTERACTIONS OF FLUORESCENT ANALOGS OF ADENINE NUCLEOTIDES

    E-Print Network [OSTI]

    Govindjee

    NUCLEOTIDES WITH COUPLING FACTOR PROTEIN ISOLATED FROM SPINACH CHLOROPLASTS David L. VANDERMEULEN by Farron [ 151, was used in determining its molarity. The fluorescent nucleotides 1,N6ethenoadenosine mono fluorescent nucleotides (mol. wt. G600) bind to the relatively large (mol. wt. = 325 000), slowly rotating CFI

  20. Photocleavable fluorescent nucleotides for DNA sequencing on a chip constructed by site-specific

    E-Print Network [OSTI]

    Church, George M.

    Photocleavable fluorescent nucleotides for DNA sequencing on a chip constructed by site sequencing by synthesis using photocleav- able (PC) fluorescent nucleotides [dUTP-PC-4,4-difluoro-4-bora-3 ,4 nucleotides to identify 7 bases in the DNA template. These results demonstrate that the PC nucleotide

  1. Spectroscopic Properties of a Self-Assembled Zinc Porphyrin Tetramer II. Time-Resolved Fluorescence Spectroscopy

    E-Print Network [OSTI]

    van Stokkum, Ivo

    Spectroscopic Properties of a Self-Assembled Zinc Porphyrin Tetramer II. Time-Resolved Fluorescence tetramer [Part I], with a 1 ns rotational correlation time at 10 °C. The initial fluorescence anisotropy of the monomer is found to be 0.1. In the tetramer an additional depolarization process occurs with a correlation

  2. Functionalized Europium Oxide Nanoparticles Used as a Fluorescent Label in an Immunoassay

    E-Print Network [OSTI]

    Hammock, Bruce D.

    Functionalized Europium Oxide Nanoparticles Used as a Fluorescent Label in an Immunoassay properties that are typical of europium, that is, a spectrally narrow, red emission and a long fluorescence may be based on lanthanide-derived phosphors. For example, the optical properties of europium chelates

  3. A simple evaluation of global and diffuse Luminous Efficacy for all sky conditions in tropical and humid climate

    E-Print Network [OSTI]

    Boyer, Edmond

    1 A simple evaluation of global and diffuse Luminous Efficacy for all sky conditions in tropical to determine luminous efficacy under different sky conditions. A comparison between these empirical constants. Keywords Global and diffuse luminous efficacy, different sky conditions, solar irradiance, solar

  4. Self-Leadership, Self-Efficacy, and Academic Performance in Undergraduate Students and Peer Mentors Lauren M Bouchard1

    E-Print Network [OSTI]

    Zhou, Yaoqi

    Self-Leadership, Self-Efficacy, and Academic Performance in Undergraduate Students and Peer Mentors of self-leadership and self-efficacy on the academic performance of students--specifically academic peer of self-leadership and self-efficacy as well as in general academic performance. Self-leadership

  5. Algorithms for Fluorescence Lifetime Microscopy and Optical Coherence Tomography Data Analysis: Applications for Diagnosis of Atherosclerosis and Oral Cancer

    E-Print Network [OSTI]

    Pande, Paritosh

    2014-05-16T23:59:59.000Z

    imaging (FLIM) with optical coherence tomography (OCT), for the diagnosis of atherosclerosis and oral cancer. FLIM is a fluorescence imaging technique that is capable of providing information about auto fluorescent tissue biomolecules. OCT on the other...

  6. Breaking the Diffraction Barrier in Fluorescence Microscopy by Optical Shelving Stefan Bretschneider, Christian Eggeling, and Stefan W. Hell*

    E-Print Network [OSTI]

    Weeks, Eric R.

    Breaking the Diffraction Barrier in Fluorescence Microscopy by Optical Shelving Stefan the breaking of the diffraction resolution barrier in far-field fluorescence microscopy by transiently shelving barrier by shelving the fluorophore in a metastable dark state, thereby effectively depleting

  7. Electronic starter device for fluorescent lamps. Final report

    SciTech Connect (OSTI)

    NONE

    1998-06-01T23:59:59.000Z

    Due to silicon supplier failures to produce the 03/04 triac silicon as specified in the original proposal, the direction of the starter program was migrated to use available off the shelf power semiconductors. This had unexpected positive side effects including a reduction in component price, improved quality, and the refocus of engineering efforts to concentrate on the Super ASIC core technology. The starter program has begun shipments employing this new architecture, and is being well received both in the US and abroad. In its present form, the starter meets original cost projections within 20%. Work is continuing on the 0.8 micron ASIC, which will allow for the starter to sell below $1.00 in volume. Even at the slightly higher price, interest is strong in replacing the low performance glow starter for small fluorescent applications with a high performance alternative.

  8. Improving the delivery and efficacy of molecular medicine via extracellular matrix modulation : insights from intravital microscopy

    E-Print Network [OSTI]

    McKee, Trevor David

    2005-01-01T23:59:59.000Z

    The extracellular matrix of tumors is a major barrier to the delivery of molecular medicine. We used fluorescence recovery after photobleaching combined with intravital microscopy to quantitate the transport properties of ...

  9. Fiber-optic fluorescence imaging Benjamin A Flusberg, Eric D Cocker,Wibool Piyawattanametha, Juergen C Jung,

    E-Print Network [OSTI]

    Cai, Long

    Fiber-optic fluorescence imaging Benjamin A Flusberg, Eric D Cocker,Wibool Piyawattanametha, Juergen C Jung, Eunice L M Cheung & Mark J Schnitzer Optical fibers guide light between separate locations and enable new types of fluorescence imaging. Fiber-optic fluorescence imaging systems include portable

  10. Cyanine-based probe\\tag-peptide pair for fluorescence protein imaging and fluorescence protein imaging methods

    DOE Patents [OSTI]

    Mayer-Cumblidge, M. Uljana (Richland, WA); Cao, Haishi (Richland, WA)

    2010-08-17T23:59:59.000Z

    A molecular probe comprises two arsenic atoms and at least one cyanine based moiety. A method of producing a molecular probe includes providing a molecule having a first formula, treating the molecule with HgOAc, and subsequently transmetallizing with AsCl.sub.3. The As is liganded to ethanedithiol to produce a probe having a second formula. A method of labeling a peptide includes providing a peptide comprising a tag sequence and contacting the peptide with a biarsenical molecular probe. A complex is formed comprising the tag sequence and the molecular probe. A method of studying a peptide includes providing a mixture containing a peptide comprising a peptide tag sequence, adding a biarsenical probe to the mixture, and monitoring the fluorescence of the mixture.

  11. Efficacy of Misuse Detection in Adhoc Networks Dhanant Subhadrabandhu, Saswati Sarkar, and Farooq Anjum

    E-Print Network [OSTI]

    Sarkar, Saswati

    1 Efficacy of Misuse Detection in Adhoc Networks Dhanant Subhadrabandhu, Saswati Sarkar, and Farooq. Subhadrabandhu and S. Sarkar are at the department of Electrical and Systems Engineering at the University

  12. Improved model for the analysis of air fluorescence induced by electrons

    E-Print Network [OSTI]

    F. Arqueros; F. Blanco; J. Rosado

    2008-07-24T23:59:59.000Z

    A model recently proposed for the calculation of air-fluorescence yield excited by electrons is revisited. Improved energy distributions of secondary electrons and a more realistic Monte Carlo simulation including some additional processes have allowed us to obtain more accurate results. The model is used to study in detail the relationship between fluorescence intensity and deposited energy in a wide range of primary energy (keVs - GeVs). In addition, predictions on the absolute value of the fluorescence efficiency in the absence of collisional quenching will be presented and compared with available experimental data.

  13. On-site demonstration procedure for solid-state fluorescent ballast

    SciTech Connect (OSTI)

    Verderber, R.; Morse, O.

    1980-09-01T23:59:59.000Z

    The report was presented to plant engineers and managers who were involved in an on-site demonstration of EETech solid-state ballasts for two 40-watt T12 fluorescent lamps. The report includes a brief review of the operating principles of solid-state fluorescent ballasts and the status of development achieved during the LBL program. The remainder of the test describes the techniques of managing and instrumenting a test area for assessing the performance of solid-state fluorescent ballasts at an occupied site.

  14. Airborne laser induced fluorescence imaging. Innovative technology summary report

    SciTech Connect (OSTI)

    NONE

    1999-06-01T23:59:59.000Z

    Laser-Induced Fluorescence (LIF) was demonstration as part of the Fernald Environmental Management Project (FEMP) Plant 1 Large Scale Demonstration and Deployment Project (LSDDP) sponsored by the US Department of Energy (DOE) Office of Science and Technology, Deactivation and Decommissioning Focus Area located at the Federal Energy Technology Center (FETC) in Morgantown, West Virginia. The demonstration took place on November 19, 1996. In order to allow the contaminated buildings undergoing deactivation and decommissioning (D and D) to be opened to the atmosphere, radiological surveys of floors, walls and ceilings must take place. After successful completion of the radiological clearance survey, demolition of the building can continue. Currently, this process is performed by collecting and analyzing swipe samples for radiological analysis. Two methods are used to analyze the swipe samples: hand-held frisker and laboratory analysis. For the purpose of this demonstration, the least expensive method, swipe samples analyzed by hand-held frisker, is the baseline technology. The objective of the technology demonstration was to determine if the baseline technology could be replaced using LIF.

  15. Diagnostic Implications of the Reactivity of Fluorescence Tracers

    SciTech Connect (OSTI)

    Sick, V; Westbrook, C

    2008-07-14T23:59:59.000Z

    Measurements of fuel concentration distributions with planar laser induced fluorescence of tracer molecules that are added to a base fuel are commonly used in combustion research and development. It usually is assumed that the tracer concentration follows the parent fuel concentration if physical properties such as those determining evaporation are matched. As an example to address this general issue a computational study of combustion of biacetyl/iso-octane mixtures was performed to investigate how well the concentration of biacetyl represents the concentration of iso-octane. For premixed mixture conditions with flame propagation the spatial concentration profiles of the two species in the flame front are separated by 110 {micro}m at 1 bar and by 11 {micro}m at 10 bar. For practical applications this spatial separation is insignificantly small. However, for conditions that mimic ignition and combustion in diesel and HCCI-like operation the differences in tracer and fuel concentration can be significant, exceeding hundreds of percent. At low initial temperature biacetyl was found to be more stable whereas at higher temperature (>1000K) iso-octane is more stable. Similar findings were obtained for a multi-component fuel comprised of iso-octane, n-heptane, methylcyclohexane, and toluene. It may be assumed that similar differences can exist for other tracer/fuel combinations. Caution has therefore to be applied when interpreting PLIF measurements in homogeneous reaction conditions such as in HCCI engine studies.

  16. Simulation of Nuclear Resonance Fluorescence in Geant4

    SciTech Connect (OSTI)

    Jordan, David V.; Warren, Glen A.

    2007-12-31T23:59:59.000Z

    Abstract– Ongoing research at Pacific Northwest National Laboratory (PNNL) is assessing the utility of exploiting nuclear resonance fluorescence (NRF) to detect bulk samples of special nuclear materials, high explosives, and related illicit cargo constituents in a variety of cargo inspection scenarios. PNNL has developed a Monte Carlo radiation transport simulation capability for studying the NRF signal response in order to facilitate computational studies of these inspection scenarios. The simulation framework implements NRF as a new physics process, “G4NRF,” in the Geant4 modeling toolkit, and leverages the Evaluated Nuclear Structure Data File (ENSDF) database of nuclear level properties to determine isotope-specific parameters of the NRF response model in general cargo constituents. The G4NRF package has been benchmarked against bremsstrahlung photon-beam data collected at the University of California at Santa Barbara’s 5.3 MeV accelerator. A series of cargo-inspection scenario studies utilizing the NRF simulation package is currently in progress.

  17. Portable x-ray fluorescence spectrometer. Innovative technology summary report

    SciTech Connect (OSTI)

    NONE

    1998-12-01T23:59:59.000Z

    This report describes the application of portable X-ray fluorescence (XRF) spectrometry to characterize materials related to deactivation and decommissioning (D and D) of contaminated facilities. Two portable XRF instruments manufactured by TN Spectrace were used in a technology evaluation as part of the Large-Scale Demonstration Project (LSDP) held at the Chicago Pile-5 Research Reactor (CP-5) located at Argonne National Laboratory (ANL). The LSDP is sponsored by the US Department of Energy (DOE), Office of Science and Technology, Deactivation and Decommissioning Focus Are (DDFA). The objective of the LSDP is to demonstrate innovative technologies or technology applications potentially beneficial to the D and D of contaminated facilities. The portable XRF technology offers several potential benefits for rapid characterization of facility components and contaminants, including significant cost reduction, fast turnaround time,a nd virtually no secondary waste. Field work for the demonstration of the portable XRF technology was performed from August 28--September 3, 1996 and October 30--December 13, 1996.

  18. Fluorescence from a quantum dot and metallic nanosphere hybrid system

    SciTech Connect (OSTI)

    Schindel, Daniel G. [Department of Mathematics and Statistics, University of Winnipeg, 515 Portage Avenue, Winnipeg, MB, R3B 2E9 (Canada); Singh, Mahi R. [Department of Physics and Astronomy, University of Western Ontario, 1151 Richmond Street, London, ON, N6A 3K7 (Canada)

    2014-03-31T23:59:59.000Z

    We present energy absorption and interference in a quantum dot-metallic nanosphere system embedded on a dielectric substrate. A control field is applied to induce dipole moments in the nanosphere and the quantum dot, and a probe field is applied to monitor absorption. Dipole moments in the quantum dot or the metal nanosphere are induced, both by the external fields and by each other's dipole fields. Thus, in addition to direct polarization, the metal nanosphere and the quantum dot will sense one another via the dipole-dipole interaction. The density matrix method was used to show that the absorption spectrum can be split from one peak to two peaks by the control field, and this can also be done by placing the metal sphere close to the quantum dot. When the two are extremely close together, a self-interaction in the quantum dot produces an asymmetry in the absorption peaks. In addition, the fluorescence efficiency can be quenched by the addition of a metal nanosphere. This hybrid system could be used to create ultra-fast switching and sensing nanodevices.

  19. Computational Prediction of Absorbance Maxima for a Structurally Diverse Series of Engineered Green Fluorescent Protein Chromophores

    E-Print Network [OSTI]

    Campbell, Robert E.

    Fluorescent Protein Chromophores Qadir K. Timerghazin, Haley J. Carlson, Chen Liang, Robert E. Campbell,* and Alex Brown* UniVersity of Alberta, Department of Chemistry, Edmonton, Alberta T6G 2G2, Canada Recei

  20. A parallel adaptive finite element simplified spherical harmonics approximation solver for frequency domain fluorescence molecular imaging

    E-Print Network [OSTI]

    Virginia Tech

    fluorescence molecular imaging Yujie Lu1 , Banghe Zhu1 , Haiou Shen2 , John C Rasmussen1 , Ge Wang2 and Eva M of the domain at excitation and emission wavelengths xf a absorption coefficient of the fluorophore cb light

  1. Supervised Machine Learning Algorithms for Early Detection of Oral Epithelial Cancer Using Fluorescence Lifetime Imaging Microscopy

    E-Print Network [OSTI]

    Lee, Joohyung

    2014-08-06T23:59:59.000Z

    In this study, the clinical potential of the endogenous multispectral Fluorescence lifetime imaging microscopy (FLIM) was investigated to objectively detect oral cancer. To this end, in vivo FLIM imaging was performed on a hamster cheek pouch model...

  2. The Application of Fluorescence Lifetime Imaging Microscopy to Quantitatively Map Mixing and Temperature in Microfluidic Systems 

    E-Print Network [OSTI]

    Graham, Emmelyn M

    2008-01-01T23:59:59.000Z

    The technique of Fluorescence Lifetime Imaging Microscopy (FLIM) has been employed to quantitatively and spatially map the fluid composition and temperature within microfluidic systems. A molecular probe with a ...

  3. Mechanism of the efficient quenching of tryptophan fluorescence in human gamma crystallin

    E-Print Network [OSTI]

    Chen, Jiejin, Ph. D. Massachusetts Institute of Technology

    2008-01-01T23:59:59.000Z

    Quenching of the fluorescence of buried tryptophans (Trps) is an important reporter of protein conformation. Human [gamma]D-crystallin (H[gamma]D-Crys) and human [gamma]S-crystallin (H[gamma]S-Crys) are both very stable ...

  4. Synthesis and Characterization of Novel Fluorescent Injectable Micro-Carriers for Tissue Regeneration

    E-Print Network [OSTI]

    Arora, Akshi

    2014-04-28T23:59:59.000Z

    Specific problem: Our previous study showed that the nanofibrous poly-l-lactic acid (NF-PLLA) microspheres are excellent cell carriers for tissue regeneration. However, these injectable microspheres are not fluorescent biomaterials. Incorporation...

  5. Optimization of Two-photon Excited Fluorescence Enhancement between Tunable and Broadband Femtosecond Laser Pulse Excitations

    E-Print Network [OSTI]

    Wang, Chao

    2012-02-14T23:59:59.000Z

    This project explores optimization of two-photon excited fluorescence (TPEF) enhancement between tunable narrowband and un-tuned broadband femtosecond (fs) laser pulse excitations for two-photon microscopy (TPM). The research is conducted...

  6. Examining 239Pu and 240Pu Nuclear Resonance Fluorescence Measurements on Spent Fuel for Nuclear Safeguards

    E-Print Network [OSTI]

    Quiter, Brian

    2013-01-01T23:59:59.000Z

    10- 01096) Journal of Nuclear Technology, p. 150, Vol. 175,linac and laser technologies for nuclear photonics gamma-rayNuclear resonance fluorescence (NRF) has been identified as a technology

  7. Non-invasive detection of oral cancer using reflectance and fluorescence spectroscopy

    E-Print Network [OSTI]

    McGee, Sasha Alanda

    2008-01-01T23:59:59.000Z

    In vivo reflectance and fluorescence spectra were collected from patients with oral lesions, as well as healthy volunteers, in order to evaluate the potential of spectroscopy to serve as a non-invasive tool for the detection ...

  8. Quantitative microscopic spectral fluorescence measurement of crude oil, bitumen, kerogen, and coal

    SciTech Connect (OSTI)

    Mukhopadhyay, P.K.; Rullkoetter, J.

    1986-05-01T23:59:59.000Z

    Ten samples each of black shale (kerogen and bitumen fractions) from Lias epsilon, coal from Western Canada and nine crude oil and condensate samples from Alaska and northern Germany have been studied using quantitative microscopic spectral fluorescence. The parameters used are lambda/sub max/, red/green quotient (Q), and alteration of fluorescence emission intensity under UV excitation. Using the same parameters, the data show that kerogen and crude oil have opposite maturation trends. Autochthonous bitumens include both kerogen and crude oil characters. Immature, biodegraded, or normal crude oil of different maturity can be characterized using these parameters. Quantitative spectral fluorescence microscopy yields more accurate maturation parameters for the Type I and II kerogens than vitrinite reflectance because the fluorescence of liptinites are used (i.e., the main oil-generating macerals). This method may become the most suitable inexpensive scanning technique for the characterization of crude oil, condensate, and autochthonous/allochthonous source rock bitumens.

  9. Measurement and model assessment of fluorescence lifetime sensing in multiply scattering media

    E-Print Network [OSTI]

    Kuwana, Eddy

    2005-08-29T23:59:59.000Z

    fluorescent dyes, 3,3-diethylthiatricarbocyanine iodide (DTTCI) and Indocynanine Green (ICG), which exhibit distinctly different lifetimes and each exhibits single-exponential decay kinetics, were employed. Measurements of phase-modulation as a function...

  10. LED-Induced Fluorescence System for Tea Classification and Quality Assessment

    E-Print Network [OSTI]

    Dong, Yongjiang; Mei, Liang; Feng, Chao; Yan, Chunsheng; He, Sailing

    2013-01-01T23:59:59.000Z

    A fluorescence system is developed by using several light emitting diodes (LEDs) with different wavelengths as excitation light sources. The fluorescence detection head consists of multi LED light sources and a multimode fiber for fluorescence collection, where the LEDs and the corresponding filters can be easily chosen to get appropriate excitation wavelengths for different applications. By analyzing fluorescence spectra with the principal component analysis method, the system is utilized in the classification of four types of green tea beverages and two types of black tea beverages. Qualities of the Xihu Longjing tea leaves of different grades, as well as the corresponding liquid tea samples, are studied to further investigate the ability and application of the system in the evaluation of classification/quality of tea and other foods.

  11. An improved understanding of fluorescent Zn(II) sensors and their uses in biological settings

    E-Print Network [OSTI]

    Wong, Brian Alexander

    2009-01-01T23:59:59.000Z

    Chapter 1. An Introduction to Fluorescent Zn(II) Sensors and Their Applications in Biological Systems This chapter opens with an overview of the numerous roles of zinc in biology, with an emphasis on labile Zn(II), that ...

  12. Turn-on fluorescent probes for detecting nitric oxide in biology

    E-Print Network [OSTI]

    McQuade, Lindsey Elizabeth, 1981-

    2010-01-01T23:59:59.000Z

    Chapter 1. Investigating the Biological Roles of Nitric Oxide and Other Reactive Nitrogen Species Using Fluorescent Probes: This chapter presents an overview of recent progress in the field of reactive nitrogen species ...

  13. Computational image analysis of subcellular dynamics in time-lapse fluorescence microscopy

    E-Print Network [OSTI]

    Huang, Austin V., 1980-

    2005-01-01T23:59:59.000Z

    The use of image segmentation and motion tracking algorithms was adapted for analyzing time-lapse data of cells with fluorescently labeled protein. Performance metrics were devised and algorithm parameters were matched to ...

  14. Time resolved fluorescence of CdSe nanocrystals using single molecule spectroscopy

    E-Print Network [OSTI]

    Fisher, Brent R

    2005-01-01T23:59:59.000Z

    A wide variety of spectroscopic studies of CdSe nanocrystals (NCs) are presented in this thesis, all studying some aspect of the temporal evolution of NC fluorescence tinder different conditions. In particular the methods ...

  15. Stardust Interstellar Preliminary Examination VI: Quantitative elemental analysis by synchrotron X-ray fluorescence nanoimaging of eight impact features in aerogel

    E-Print Network [OSTI]

    Nittler, Larry R.

    -ray fluorescence nanoimaging of eight impact features in aerogel Alexandre S. SIMIONOVICI1* , Laurence LEMELLE2

  16. Automation of the Laguerre Expansion Technique for Analysis of Time-resolved Fluorescence Spectroscopy Data

    E-Print Network [OSTI]

    Dabir, Aditi Sandeep

    2010-07-14T23:59:59.000Z

    AUTOMATION OF THE LAGUERRE EXPANSION TECHNIQUE FOR ANALYSIS OF TIME-RESOLVED FLUORESCENCE SPECTROSCOPY DATA A Thesis by ADITI SANDEEP DABIR Submitted to the Office of Graduate Studies of Texas A&M University in partial... fulfillment of the requirements for the degree of MASTER OF SCIENCE December 2009 Major Subject: Biomedical Engineering AUTOMATION OF THE LAGUERRE EXPANSION TECHNIQUE FOR ANALYSIS OF TIME-RESOLVED FLUORESCENCE SPECTROSCOPY DATA A Thesis...

  17. On-line measurement of lignin in wood pulp by color shift of fluorescence

    DOE Patents [OSTI]

    Jeffers, L.A.; Malito, M.L.

    1996-01-23T23:59:59.000Z

    Lignin concentrations from wood pulp samples are measured by applying an excitation light at a selected wavelength to the samples in order to cause the lignin to emit fluorescence. A spectral distribution of the fluorescence emission is then determined. The lignin concentration is then calculated based on the spectral distribution signal. The spectral distribution is quantified by either a wavelength centroid method or a band ratio method. 6 figs.

  18. On-line measurement of lignin in wood pulp by color shift of fluorescence

    DOE Patents [OSTI]

    Jeffers, Larry A. (Washington Township, Stark County, OH); Malito, Michael L. (Liberty Township, Trumbull County, OH)

    1996-01-01T23:59:59.000Z

    Lignin concentrations from wood pulp samples are measured by applying an excitation light at a selected wavelength to the samples in order to cause the lignin to emit fluorescence. A spectral distribution of the fluorescence emission is then determined. The lignin concentration is then calculated based on the spectral distribution signal. The spectral distribution is quantified by either a wavelength centroid method or a band ratio method.

  19. Analyzing fluorophore electronic structure and depolarization by fluorescence polarizing angle spectrum

    SciTech Connect (OSTI)

    Mu, Taotao; Chen, Siying, E-mail: csy@bit.edu.cn; Zhang, Yinchao; Chen, He; Guo, Pan [School of Optoelectronics, Beijing Institute of Technology, Beijing 100081 (China)

    2014-07-21T23:59:59.000Z

    In this Letter, a method, based on stokes parameters, is developed to observe the angular displacement between the excitation and emission moments. Experiments demonstrate that when combined with degree of polarization spectrums, we can acquire the depolarization caused by angular displacement or energy migration. The method presented in this Letter can be easily realized with the existing fluorescence measuring system and may potentially make it convenient to study the fluorophore electronic structure or the mechanism of fluorescence anisotropy.

  20. The development of an indirect fluorescent antibody test for Trypanosoma vivax in Colombia

    E-Print Network [OSTI]

    Platt, Kenneth Bradley

    1974-01-01T23:59:59.000Z

    THE DEVELOPMENT OF AN INDIRECT FLUORESCENT ANTIBODY TEST FOR TRYPANOSOMA VIVAX IN COLOMBIA A Thesis KENNETH BRADLEY PLATT Submitted to the Graduate College of Texas A Es M University in partial fulfillment of the requirement for the degree... of MASTEB OF SCIENCE May 1974 Ma]or Sub]ect: Veterinary Miorobiology THE DEVELOPMENT OF AN INDIRECT FLUORESCENT ANTIBODY TEST FOR TRYPANOSOMA VIVAX IN COLOMBIA A Thesis by KENNETH BRADLEY PLATT Approved as to style end content by: Co-Cha rman...

  1. Organic light-emitting device with a phosphor-sensitized fluorescent emission layer

    DOE Patents [OSTI]

    Forrest, Stephen (Ann Arbor, MI); Kanno, Hiroshi (Osaka, JP)

    2009-08-25T23:59:59.000Z

    The present invention relates to organic light emitting devices (OLEDs), and more specifically to OLEDS that emit light using a combination of fluorescent emitters and phosphorescent emitters. The emissive region of the devices of the present invention comprise at least one phosphor-sensitized layer which has a combined emission from a phosphorescent emitter and a fluorescent emitter. In preferred embodiments, the invention relates to white-emitting OLEDS (WOLEDs).

  2. Assessment of Nuclear Resonance Fluorescence for Spent Nuclear Fuel Assay

    SciTech Connect (OSTI)

    Quiter, Brian; Ludewigt, Bernhard; Ambers, Scott

    2011-06-30T23:59:59.000Z

    In nuclear resonance fluorescence (NRF) measurements, resonances are excited by an external photon beam leading to the emission of gamma rays with specific energies that are characteristic of the emitting isotope. NRF promises the unique capability of directly quantifying a specific isotope without the need for unfolding the combined responses of several fissile isotopes as is required in other measurement techniques. We have analyzed the potential of NRF as a non-destructive analysis technique for quantitative measurements of Pu isotopes in spent nuclear fuel (SNF). Given the low concentrations of 239Pu in SNF and its small integrated NRF cross sections, the main challenge in achieving precise and accurate measurements lies in accruing sufficient counting statistics in a reasonable measurement time. Using analytical modeling, and simulations with the radiation transport code MCNPX that has been experimentally tested recently, the backscatter and transmission methods were quantitatively studied for differing photon sources and radiation detector types. Resonant photon count rates and measurement times were estimated for a range of photon source and detection parameters, which were used to determine photon source and gamma-ray detector requirements. The results indicate that systems based on a bremsstrahlung source and present detector technology are not practical for high-precision measurements of 239Pu in SNF. Measurements that achieve the desired uncertainties within hour-long measurements will either require stronger resonances, which may be expressed by other Pu isotopes, or require quasi-monoenergetic photon sources with intensities that are approximately two orders of magnitude higher than those currently being designed or proposed.This work is part of a larger effort sponsored by the Next Generation Safeguards Initiative to develop an integrated instrument, comprised of individual NDA techniques with complementary features, that is fully capable of determining Pu mass in spent fuel assemblies.

  3. Conservation potential of compact fluorescent lamps in India and Brazil

    SciTech Connect (OSTI)

    Gadgil, A.; Martino Jannuzzi, G. de (Lawrence Berkeley Lab., CA (USA); Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia)

    1989-07-01T23:59:59.000Z

    We evaluate the conservation potential of compact fluorescent lamps (CFLs) for managing the rapidly increasing electrical energy and peak demand in India and Brazil. Using very conservative assumptions, we find that the cost of conserved energy using 16 W CFLs is 4 and 6 times less than the long range marginal cost of electricity for the two countries. The cost of avoided peak installed capacity is 6 and 9.5 times less than the cost of new installed capacity for India and Brazil. The analysis is undertaken from the three separate perspectives of the national economies, the consumers, and the utilities. We find that because residential electricity is subsidized, the consumers have little or no incentive to purchase and install the CFLs, unless they too are subsidized. However, the benefits of CFL installation to the utility are so large that subsidizing them is a paying proposition for the utility are so large that subsidizing them is a paying proposition for the utility in almost all cases. As an illustration of a gradual introduction strategy for CFLs, we calculate a scenario where national savings of the order of US $1.2 million per day for India and US $2.5 million per day for Brazil are reached in 10 years by a small and gradual transfer of subsidy from residential electricity to CFLs. We then explore the barriers to immediate large scale introduction of these lamps in the two countries. Specific technical and marketing problems are identified and discussed, which would require solution before such an introduction can be attempted. Lastly, we discuss the range of policy instruments, in addition to a subsidy scheme, that can be used for promoting the diffusion of these lamps in the domestic and commercial sector. 47 refs., 15 figs., 2 tabs.

  4. Feasibility of x ray fluorescence for spent fuel safeguards

    SciTech Connect (OSTI)

    Freeman, Corey Ross [Los Alamos National Laboratory; Mozin, Vladimir [Los Alamos National Laboratory; Tobin, Stephen J [Los Alamos National Laboratory; Fensin, Michael L [Los Alamos National Laboratory; White, Julia M [Los Alamos National Laboratory; Croft, Stephen [Los Alamos National Laboratory; Stafford, Alissa [TAMU; Charlton, William [TAMU

    2010-01-01T23:59:59.000Z

    Quantifying the Pu content in spent nuclear fuel is necessary for many reasons, in particular to verify that diversion or other illicit activities have not occurred. Therefore, safeguarding the world's nuclear fuel is paramount to responsible nuclear regulation and public acceptance, but achieving this goal presents many difficulties from both a technical and economic perspective. The Next Generation Safeguards Initiative (NGSI) of NA-24 is funding a large collaborative effort between multiple laboratories and universities to improve spent nuclear fuel safeguards methods and equipment. This effort involves the current work of modeling several different nondestructive assay (NDA) techniques. Several are being researched, because no single NDA technique, in isolation, has the potential to properly characterize fuel assemblies and offer a robust safeguards measure. The insights gained from this research, will be used to down-select from the original set a few of the most promising techniques that complement each other. The goal is to integrate the selected instruments to create an accurate measurement system for fuel verification that is also robust enough to detect diversions. These instruments will be fabricated and tested under realistic conditions. This work examines one of the NDA techniques; the feasibility of using x ray emission peaks from Pu and U to gather information about their relative quantities in the spent fuel. X Ray Fluorescence (XRF), is unique compared to the investigated techniques in that it is the only one able to give the elemental ratio of Pu to U, allowing the possibility of a Pu gram quantity for the assembly to be calculated. XRF also presents many challenges, mainly its low penetration, since the low energy x rays of interest are effectively shielded by the first few millimeters of a fuel pin. This paper will explore the results of Monte Carlo N-Particle eXtended (MCNPX) transport code calculations of spent fuel x ray peaks. The MCNPX simulations will be benchmarked against measurements taken at Oak Ridge. Analysis of the feasibility of XRFs role in spent nuclear fuel safeguards efforts, particularly in the context of the overall NGSI effort will be discussed.

  5. X-Ray Fluorescence (XRF) Analysis of Obsidian Artifacts from AZ AA:8:20 (ASM), Southeastern Arizona

    E-Print Network [OSTI]

    Shackley, M. Steven

    1986-01-01T23:59:59.000Z

    Minerologist 62:426-437. SOUTHWEST XRF PAPER Tabl;o:. X-:'~vX-RAY FLUORESCENCE (XRF) ANALYSIS OF OBSIDIAN ARTIFACTS FROM

  6. Calculating the contribution of different binding modes to Quinacrine - DNA complex formation from polarized fluorescence data

    E-Print Network [OSTI]

    Voloshin, Igor; Karachevtsev, Victor; Zozulya, Victor

    2013-01-01T23:59:59.000Z

    Binding of acridine derivative quinacrine (QA) to chicken erythrocyte DNA was studied by methods of absorption and polarized fluorescent spectroscopy. Measurements were carried out in aqueous buffered solutions (pH 6.9) of different dye concentrations (QA concentration range from $10^{-6}$ till $10^{-4}$ M) and ionic strengths ($Na^{+}$ concentration rang from $10^{-3}$ till 0.15 M) in a wide range of phosphate-to-dye molar ratios ($P/D$). It is established that the minimum of fluorescent titration curve plotted as relative fluorescence intensity $vs$ $P/D$ is conditioned by the competition between the two types of QA binding to DNA which posses by different emission parameters: (i) intercalative one dominating under high $P/D$ values, and (ii) outside electrostatic binding dominating under low $P/D$ values, which is accompanied by the formation of non-fluorescent dye associates on the DNA backbone. Absorption and fluorescent characteristics of complexes formed were determined. The method of calculation of di...

  7. Optimized scalable stack of fluorescent solar concentrator systems with bifacial silicon solar cells

    SciTech Connect (OSTI)

    Martínez Díez, Ana Luisa, E-mail: a.martinez@itma.es [Fundación ITMA, Parque Empresarial Principado de Asturias, C/Calafates, Parcela L-3.4, 33417 Avilés (Spain); Fraunhofer Institute for Solar Energy Systems ISE, Heidenhofstr. 2, 79110 Freiburg (Germany); Gutmann, Johannes; Posdziech, Janina; Rist, Tim; Goldschmidt, Jan Christoph [Fraunhofer Institute for Solar Energy Systems ISE, Heidenhofstr. 2, 79110 Freiburg (Germany); Plaza, David Gómez [Fundación ITMA, Parque Empresarial Principado de Asturias, C/Calafates, Parcela L-3.4, 33417 Avilés (Spain)

    2014-10-21T23:59:59.000Z

    In this paper, we present a concentrator system based on a stack of fluorescent concentrators (FCs) and a bifacial solar cell. Coupling bifacial solar cells to a stack of FCs increases the performance of the system and preserves its efficiency when scaled. We used an approach to optimize a fluorescent solar concentrator system design based on a stack of multiple fluorescent concentrators (FC). Seven individual fluorescent collectors (20 mm×20 mm×2 mm) were realized by in-situ polymerization and optically characterized in regard to their ability to guide light to the edges. Then, an optimization procedure based on the experimental data of the individual FCs was carried out to determine the stack configuration that maximizes the total number of photons leaving edges. Finally, two fluorescent concentrator systems were realized by attaching bifacial silicon solar cells to the optimized FC stacks: a conventional system, where FC were attached to one side of the solar cell as a reference, and the proposed bifacial configuration. It was found that for the same overall FC area, the bifacial configuration increases the short-circuit current by a factor of 2.2, which is also in agreement with theoretical considerations.

  8. A fluorescence-based method for rapid and direct determination of Polybrominated Diphenyl Ethers in Water

    SciTech Connect (OSTI)

    Shan, Huimei; Liu, Chongxuan; Wang, Zheming; Ma, Teng; Shang, Jianying; Pan, Duoqiang

    2015-01-01T23:59:59.000Z

    A new method was developed for rapid and direct measurement of aqueous polybrominated diphenyl ethers (PBDEs) using fluorescence spectroscopy. The fluorescence spectra of aqueous tri- to deca-BDE (BDE28, 47, 99, 153, 190 and 209) that are commonly found in environment were determined at variable emission and excitation wavelengths. The results revealed that the PBDEs have distinct fluorescence spectral profiles and peak positions that can be exploited to identify these species and determine their concentrations in aqueous solutions. The detection limits as determined in deionized water spiked with PBDEs are 1.71-5.82 ng/L for BDE28, BDE47, BDE190 and BDE209, and 45.55-69.95 ng/L for BDE99 and BDE153. The effects of environmental variables including pH, humic substance, and groundwater chemical composition on PBDEs measurements were also investigated. These environmental variables affected fluorescence intensity, but their effect can be corrected through linear additivity and separation of spectral signal contribution. Compared with conventional GC-based analytical methods, the fluorescence spectroscopy method is more efficient as it only uses a small amount of samples (4 ml), avoids lengthy complicated concentration and extraction steps, and has a low detection limit of a few ng/L.

  9. Method for detecting point mutations in DNA utilizing fluorescence energy transfer

    DOE Patents [OSTI]

    Parkhurst, Lawrence J. (Lincoln, NE); Parkhurst, Kay M. (Lincoln, NE); Middendorf, Lyle (Lincoln, NE)

    2001-01-01T23:59:59.000Z

    A method for detecting point mutations in DNA using a fluorescently labeled oligomeric probe and Forster resonance energy transfer (FRET) is disclosed. The selected probe is initially labeled at each end with a fluorescence dye, which act together as a donor/acceptor pair for FRET. The fluorescence emission from the dyes changes dramatically from the duplex stage, wherein the probe is hybridized to the complementary strand of DNA, to the single strand stage, when the probe is melted to become detached from the DNA. The change in fluorescence is caused by the dyes coming into closer proximity after melting occurs and the probe becomes detached from the DNA strand. The change in fluorescence emission as a function of temperature is used to calculate the melting temperature of the complex or T.sub.m. In the case where there is a base mismatch between the probe and the DNA strand, indicating a point mutation, the T.sub.m has been found to be significantly lower than the T.sub.m for a perfectly match probelstand duplex. The present invention allows for the detection of the existence and magnitude of T.sub.m, which allows for the quick and accurate detection of a point mutation in the DNA strand and, in some applications, the determination of the approximate location of the mutation within the sequence.

  10. Development of Best Practices for Shell Egg Disinfection Based upon Efficacy and Egg Quality

    E-Print Network [OSTI]

    Al-Ajeeli, Morouj N

    2013-12-04T23:59:59.000Z

    ; 2) assess the efficacy of chlorine, quaternary ammonium compounds (QAC), peracetic acid alone or in combination with ultraviolet (UV) light and hydrogen peroxide (H2O2) (3.5%) in combination with UV light as post-wash sanitizers against aerobic plate...

  11. ORIGINAL ARTICLE Enhanced therapeutic efficacy of IL-12, but not GM-CSF,

    E-Print Network [OSTI]

    Cai, Long

    ORIGINAL ARTICLE Enhanced therapeutic efficacy of IL-12, but not GM-CSF, expressing oncolytic herpes simplex virus for transgenic mouse derived prostate cancers S Varghese1,2 , SD Rabkin1,2 , R Liu1 and Harvard Medical School, Boston, MA, USA Replication competent oncolytic herpes simplex viruses (HSV

  12. Heat of the Moment: Characterizing the Efficacy of Thermal Camera-Based Attacks

    E-Print Network [OSTI]

    Heat of the Moment: Characterizing the Efficacy of Thermal Camera-Based Attacks Keaton Mowery UC to analyze the data. First, we present code recovery re- sults from human review of our test data set lock on an industrial safe, he found that body heat from the user transferred to the individual keys

  13. Efficacy-aware Business Process Modeling Matthias Lohrmann and Manfred Reichert

    E-Print Network [OSTI]

    Ulm, Universität

    Efficacy-aware Business Process Modeling Matthias Lohrmann and Manfred Reichert Ulm University. In business process design, business objective models can ful- fill the role of formal requirement definitions for progressive appli- cations like automated process optimization. Key words: Business Process Modeling

  14. We compared the efficacy of positive pressure ventilation (PPV) vs negative pressure ventilation (NPV) in providing

    E-Print Network [OSTI]

    Shadmehr, Reza

    the rationale for the use ofintermittent assisted ventilation is based on the premise that it alleviates muscleWe compared the efficacy of positive pressure ventilation (PPV) vs negative pressure ventilationEMG), minute ventilation (VE),tidal volume (VT), and end-tidal CO (etCOÃ during 15 minutes of PPV and NPV

  15. Young drivers and the efficacy of the Texas drug and alcohol driving awareness program

    E-Print Network [OSTI]

    Darnell, Richard

    2009-05-15T23:59:59.000Z

    The purpose of this study was to examine the efficacy of the Texas Drug and Alcohol Driving Awareness Program (TDADAP) in relation to alcohol-related offenses among young drivers. Participants in this study were students in pre-license programs...

  16. Comparison of the Efficacy of Popular Weight Loss Programs in Sedentary Overweight Women

    E-Print Network [OSTI]

    Baetge, Claire

    2014-08-06T23:59:59.000Z

    This study compared the efficacy of the Curves® Complete 90-day Challenge (CC), Weight Watchers® Points Plus (WW), Jenny Craig® At Home (JC), and Nutrisystem® Advance Select™ (NS) on weight loss, body composition and/or markers of health and fitness...

  17. Neuropharmacology and analgesia Comparative efficacy of 3 soluble epoxide hydrolase inhibitors

    E-Print Network [OSTI]

    Hammock, Bruce D.

    Neuropharmacology and analgesia Comparative efficacy of 3 soluble epoxide hydrolase inhibitors in rat neuropathic and inflammatory pain models Karen Wagner, Bora Inceoglu, Hua Dong, Jun Yang, Sung Hee Inflammatory pain Diabetic neuropathic pain Epoxygenated fatty acid a b s t r a c t Epoxy-fatty acids have been

  18. Subunits of highly Fluorescent Protein R-Phycoerythrin as Probes for Cell Imaging and Single-Molecule Detection

    SciTech Connect (OSTI)

    Dragan Isailovic

    2005-12-17T23:59:59.000Z

    The purposes of our research were: (1) To characterize subunits of highly fluorescent protein R-Phycoerythrin (R-PE) and check their suitability for single-molecule detection (SMD) and cell imaging, (2) To extend the use of R-PE subunits through design of similar proteins that will be used as probes for microscopy and spectral imaging in a single cell, and (3) To demonstrate a high-throughput spectral imaging method that will rival spectral flow cytometry in the analysis of individual cells. We first demonstrated that R-PE subunits have spectroscopic and structural characteristics that make them suitable for SMD. Subunits were isolated from R-PE by high-performance liquid chromatography (HPLC) and detected as single molecules by total internal reflection fluorescence microscopy (TIRFM). In addition, R-PE subunits and their enzymatic digests were characterized by several separation and detection methods including HPLC, capillary electrophoresis, sodium dodecyl sulfate-polyacrilamide gel electrophoresis (SDS-PAGE) and HPLC-electrospray ionization mass spectrometry (ESI-MS). Favorable absorption and fluorescence of the R-PE subunits and digest peptides originate from phycoerythrobilin (PEB) and phycourobilin (PUB) chromophores that are covalently attached to cysteine residues. High absorption coefficients and strong fluorescence (even under denaturing conditions), broad excitation and emission fluorescence spectra in the visible region of electromagnetic spectrum, and relatively low molecular weights make these molecules suitable for use as fluorescence labels of biomolecules and cells. We further designed fluorescent proteins both in vitro and in vivo (in Escherichia coli) based on the highly specific attachment of PEB chromophore to genetically expressed apo-subunits of R-PE. In one example, apo-alpha and apo-beta R-PE subunits were cloned from red algae Polisiphonia boldii (P. boldii), and expressed in E. coli. Although expressed apo-subunits formed inclusion bodies, fluorescent holo-subunits were formed after incubation of E. coli cells with PEB. Spectroscopic characterization of holo-subunits confirmed that the attachment of PEB chromophore to apo-subunits yielded holo-subunits containing both PEB and urobilin (UB). Fluorescence and differential interference contrast (DIC) microscopy showed polar location of holo-subunit inclusion bodies in E. coli cells. In another example, R-PE apo-subunits were genetically fused to cytoplasmic and periplasmic versions of E. coli maltose binding protein (MBP). Fluorescent proteins formed after attachment of PEB to MBP-subunit fusions in vitro and in vivo contained PEB as the sole chromophore, were soluble, and displayed high orange fluorescence. Fluorescence microscopy showed that fusions are located either throughout cells or at cell poles. In addition, cells containing fluorescent holo-subunits or MBP-subunit fusions were up to ten times brighter than control cells as measured by flow cytometry. Results show that the fluorescent proteins formed after non-enzymatic attachment of PEB to R-PE subunit fusions could be used as reporters of gene expression and protein localization in cells as well as fluorescence labels in flow cytometry. Finally, we demonstrated a high-throughput method able to record emission fluorescence spectra of individual cells containing fluorescent proteins. Upon excitation with a 488 mn argon-ion laser many bacterial cells were imaged by a 20X microscope objective while they moved through a capillary tube. Fluorescence was dispersed by a transmission diffraction grating, and an intensified charge-coupled device (ICCD) camera simultaneously recorded the zero and the first orders of the fluorescence from each cell. Single-cell fluorescence spectra were reconstructed from the distance between zero-order and first-order maxima as well as the length and the pixel intensity distribution of the first-order images. By using this approach, the emission spectrum of E. coli cells expressing green fluorescent protein (GFP) was reconstructed. Also, fluorescence spectra of E

  19. Demonstration of x-ray fluorescence imaging of a high-energy-density plasma

    SciTech Connect (OSTI)

    MacDonald, M. J., E-mail: macdonm@umich.edu; Gamboa, E. J. [Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, Ann Arbor, Michigan 48109 (United States); SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Keiter, P. A.; Fein, J. R.; Klein, S. R.; Kuranz, C. C.; LeFevre, H. J.; Manuel, M. J.-E.; Wan, W. C.; Drake, R. P. [Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, Ann Arbor, Michigan 48109 (United States); Montgomery, D. S. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Biener, M. M.; Fournier, K. B. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Streit, J. [Schafer Corporation, Livermore, California 94551 (United States)

    2014-11-15T23:59:59.000Z

    Experiments at the Trident Laser Facility have successfully demonstrated the use of x-ray fluorescence imaging (XRFI) to diagnose shocked carbonized resorcinol formaldehyde (CRF) foams doped with Ti. One laser beam created a shock wave in the doped foam. A second laser beam produced a flux of vanadium He-? x-rays, which in turn induced Ti K-shell fluorescence within the foam. Spectrally resolved 1D imaging of the x-ray fluorescence provided shock location and compression measurements. Additionally, experiments using a collimator demonstrated that one can probe specific regions within a target. These results show that XRFI is a capable alternative to path-integrated measurements for diagnosing hydrodynamic experiments at high energy density.

  20. Fluorescence measurements for evaluating the application of multivariate analysis techniques to optically thick environments.

    SciTech Connect (OSTI)

    Reichardt, Thomas A.; Timlin, Jerilyn Ann; Jones, Howland D. T.; Sickafoose, Shane M.; Schmitt, Randal L.

    2010-09-01T23:59:59.000Z

    Laser-induced fluorescence measurements of cuvette-contained laser dye mixtures are made for evaluation of multivariate analysis techniques to optically thick environments. Nine mixtures of Coumarin 500 and Rhodamine 610 are analyzed, as well as the pure dyes. For each sample, the cuvette is positioned on a two-axis translation stage to allow the interrogation at different spatial locations, allowing the examination of both primary (absorption of the laser light) and secondary (absorption of the fluorescence) inner filter effects. In addition to these expected inner filter effects, we find evidence that a portion of the absorbed fluorescence is re-emitted. A total of 688 spectra are acquired for the evaluation of multivariate analysis approaches to account for nonlinear effects.

  1. Standard practice for fluorescent liquid penetrant testing using the Solvent-Removable process

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    2010-01-01T23:59:59.000Z

    1.1 This practice covers procedures for fluorescent penetrant examination utilizing the solvent-removable process. It is a nondestructive testing method for detecting discontinuities that are open to the surface, such as cracks, seams, laps, cold shuts, laminations, isolated porosity, through leaks, or lack of fusion and is applicable to in-process, final, and maintenance examination. It can be effectively used in the examination of nonporous, metallic materials, both ferrous and nonferrous, and of nonmetallic materials such as glazed or fully densified ceramics and certain nonporous plastics and glass. 1.2 This practice also provides a reference: 1.2.1 By which a fluorescent penetrant examination solvent-removable process recommended or required by individual organizations can be reviewed to ascertain its applicability and completeness. 1.2.2 For use in the preparation of process specifications dealing with the fluorescent solvent-removable liquid penetrant examination of materials and parts. Agreement by...

  2. Standard practice for fluorescent liquid penetrant testing using the hydrophilic Post-Emulsification process

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    2010-01-01T23:59:59.000Z

    1.1 This practice covers procedures for fluorescent penetrant examination utilizing the hydrophilic post-emulsification process. It is a nondestructive testing method for detecting discontinuities that are open to the surface such as cracks, seams, laps, cold shuts, laminations, isolated porosity, through leaks, or lack of fusion and is applicable to in-process, final, and maintenance examination. It can be effectively used in the examination of nonporous, metallic materials, both ferrous and nonferrous, and of nonmetallic materials such as glazed or fully densified ceramics and certain nonporous plastics and glass. 1.2 This practice also provides a reference: 1.2.1 By which a fluorescent penetrant examination hydrophilic post-emulsification process recommended or required by individual organizations can be reviewed to ascertain their applicability and completeness. 1.2.2 For use in the preparation of process specifications dealing with the fluorescent penetrant examination of materials and parts using the...

  3. Hyper-filter-fluorescer spectrometer for x-rays above 120 keV

    DOE Patents [OSTI]

    Wang, Ching L. (Livermore, CA)

    1983-01-01T23:59:59.000Z

    An apparatus utilizing filter-fluorescer combinations is provided to measure short bursts of high fluence x-rays above 120 keV energy, where there are no practical absorption edges available for conventional filter-fluorescer techniques. The absorption edge of the prefilter is chosen to be less than that of the fluorescer, i.e., E.sub.PRF E.sub.F. In this way, the response function is virtually zero between E.sub.PRF and E.sub.F and well defined and enhanced in an energy band of less than 1000 keV above the 120 keV energy.

  4. Intense Internal and External Fluorescence as Solar Cells Approach the Shockley-Queisser Efficiency Limit

    E-Print Network [OSTI]

    Miller, Owen D; Kurtz, Sarah R

    2012-01-01T23:59:59.000Z

    Absorbed sunlight in a solar cell produces electrons and holes. But, at the open circuit condition, the carriers have no place to go. They build up in density and, ideally, they emit external fluorescence that exactly balances the incoming sunlight. Any additional non-radiative recombination impairs the carrier density buildup, limiting the open-circuit voltage. At open-circuit, efficient external fluorescence is an indicator of low internal optical losses. Thus efficient external fluorescence is, counter-intuitively, a necessity for approaching the Shockley-Queisser efficiency limit. A great Solar Cell also needs to be a great Light Emitting Diode. Owing to the narrow escape cone for light, efficient external emission requires repeated attempts, and demands an internal luminescence efficiency >>90%.

  5. Laser-induced fluorescence of fused silica irradiated by ArF excimer laser

    SciTech Connect (OSTI)

    Zhang Haibo [Shanghai Key Laboratory of All Solid-state Laser and Applied Techniques, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Science, Shanghai 201800 (China); Graduate University of Chinese Academy of Science, Beijing 100049 (China); Yuan Zhijun; Zhou Jun; Dong Jingxing; Wei Yunrong; Lou Qihong [Shanghai Key Laboratory of All Solid-state Laser and Applied Techniques, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Science, Shanghai 201800 (China)

    2011-07-01T23:59:59.000Z

    Laser-induced fluorescence (LIF) of high-purity fused silica irradiated by ArF excimer laser is studied experimentally. LIF bands of the fused silica centered at 281 nm, 478 nm, and 650 nm are observed simultaneously. Furthermore, the angular distribution of the three fluorescence peaks is examined. Microscopic image of the laser modified fused silica indicates that scattering of the generated fluorescence by laser-induced damage sites is the main reason for the angular distribution of LIF signals. Finally, the dependence of LIF signals intensities of the fused silica on laser power densities is presented. LIF signals show a squared power density dependence, which indicates that laser-induced defects are formed mainly via two-photon absorption processes.

  6. A portable time-domain LED fluorimeter for nanosecond fluorescence lifetime measurements

    SciTech Connect (OSTI)

    Wang, Hongtao; Salthouse, Christopher D., E-mail: salthouse@ecs.umass.edu [Electrical and Computer Engineering Department, University of Massachusetts, Amherst, Massachusetts 01003 (United States); Center for Personalized Health Monitoring, University of Massachusetts, Amherst, Massachusetts 01003 (United States); Qi, Ying; Mountziaris, T. J. [Center for Personalized Health Monitoring, University of Massachusetts, Amherst, Massachusetts 01003 (United States) [Center for Personalized Health Monitoring, University of Massachusetts, Amherst, Massachusetts 01003 (United States); Chemical Engineering Department, University of Massachusetts, Amherst, Massachusetts 01003 (United States)

    2014-05-15T23:59:59.000Z

    Fluorescence lifetime measurements are becoming increasingly important in chemical and biological research. Time-domain lifetime measurements offer fluorescence multiplexing and improved handling of interferers compared with the frequency-domain technique. In this paper, an all solid-state, filterless, and highly portable light-emitting-diode based time-domain fluorimeter (LED TDF) is reported for the measurement of nanosecond fluorescence lifetimes. LED based excitation provides more wavelengths options compared to laser diode based excitation, but the excitation is less effective due to the uncollimated beam, less optical power, and longer latency in state transition. Pulse triggering and pre-bias techniques were implemented in our LED TDF to improve the peak optical power to over 100 mW. The proposed pulsing circuit achieved an excitation light fall time of less than 2 ns. Electrical resetting technique realized a time-gated photo-detector to remove the interference of the excitation light with fluorescence. These techniques allow the LED fluorimeter to accurately measure the fluorescence lifetime of fluorescein down to concentration of 0.5 ?M. In addition, all filters required in traditional instruments are eliminated for the non-attenuated excitation/emission light power. These achievements make the reported device attractive to biochemical laboratories seeking for highly portable lifetime detection devices for developing sensors based on fluorescence lifetime changes. The device was initially validated by measuring the lifetimes of three commercial fluorophores and comparing them with reported lifetime data. It was subsequently used to characterize a ZnSe quantum dot based DNA sensor.

  7. New maturity indicators based on spectral fluorescence of alginite and bitumen, Monterey Formation, California

    SciTech Connect (OSTI)

    Lee, Chungi; Kennicutt, M.C. II (Texas A and M Univ., College Station (United States)); Lo, H.B. (Exxon Production Research Co., Houston, TX (United States))

    1991-03-01T23:59:59.000Z

    Conventional assessment of maturation level in the Monterey has been problematic, since sporinite and vitrinite are rare or absent. Organic matter is largely alginite and amorphous material, and reliable vitrinite reflectance (R{sub o}%) and Thermal Alteration Index (TAI) are difficult to obtain. Large amounts of bitumen often imbedded in the highly fractured Monterey shales cause a suppression of T{sub max} and low values of S{sub 1}S{sub 1} + S{sub 2}. It is often difficult to determine whether bitumen is indigenous or migrated from other more mature strata. Spectral fluorescence measurements of alginite and bitumen have proved useful in assessing the maturity of the Monterey. A maturity scale based on red/green quotient (Q{sub v}) measured as the fluorescence of alginite B when excited by violet-light has been developed and applied to the Monterey. Alginite B is common in the Monterey, and accurate fluorescent measurements can be readily obtained given the highly fluorescent character of alginite B. A total scanning fluorescence technique was used to develop a maturity scale based on bitumen aromatic content and composition. The maturity parameter (R{sub 1}) developed in this study uses the intensity of fluorescence emitted at 360 nm ratioed to that at 320 nm when the solvent-dissolved bitumen is excited at the 270 nm. These parameters allow for the evaluation of the thermal maturity of algal organic matter and bitumen from the Monterey with R{sub o}% {lt} 1. Indigenous bitumen is also indicated by a comparison of maturity based on Q{sub v} (the solid phase) and bitumen maturity (the liquid phase) based on R{sub 1}.

  8. Simultaneous two-dimensional laser-induced-fluorescence measurements of argon ions

    SciTech Connect (OSTI)

    Hansen, A. K.; Galante, Matthew; McCarren, Dustin; Sears, Stephanie; Scime, E. E. [Department of Physics, West Virginia University, P.O. Box 6315, Morgantown, West Virginia 26506-6315 (United States)

    2010-10-15T23:59:59.000Z

    Recent laser upgrades on the Hot Helicon Experiment at West Virginia University have enabled multiplexed simultaneous measurements of the ion velocity distribution function at a single location, expanding our capabilities in laser-induced fluorescence diagnostics. The laser output is split into two beams, each modulated with an optical chopper and injected perpendicular and parallel to the magnetic field. Light from the crossing point of the beams is transported to a narrow-band photomultiplier tube filtered at the fluorescence wavelength and monitored by two lock-in amplifiers, each referenced to one of the two chopper frequencies.

  9. Method for detecting binding events using micro-X-ray fluorescence spectrometry

    DOE Patents [OSTI]

    Warner, Benjamin P. (Los Alamos, NM); Havrilla, George J. (Los Alamos, NM); Mann, Grace (Hong Kong, HK)

    2010-12-28T23:59:59.000Z

    Method for detecting binding events using micro-X-ray fluorescence spectrometry. Receptors are exposed to at least one potential binder and arrayed on a substrate support. Each member of the array is exposed to X-ray radiation. The magnitude of a detectable X-ray fluorescence signal for at least one element can be used to determine whether a binding event between a binder and a receptor has occurred, and can provide information related to the extent of binding between the binder and receptor.

  10. Measurement of Pressure Dependent Fluorescence Yield of Air: Calibration Factor for UHECR Detectors

    SciTech Connect (OSTI)

    Belz, J.W.; Burt, G.W.; Cao, Z.; Chang, F.Y.; Chen, C.C.; Chen, C.W.; Chen, P.; Field, C.; Findlay, J.; Huntemeyer, Petra; Huang, M.A.; Hwang, W.-Y.P.; Iverson, R.; Jones, B.F.; Jui, C.C.H.; Kirn, M.; Lin, G.-L.; Loh, E.C.; Maestas, M.M.; Manago, N.; Martens, K.; /Montana U. /Utah U. /Taiwan, Natl. Taiwan U. /SLAC /Rutgers U., Piscataway

    2005-07-06T23:59:59.000Z

    In a test experiment at the Final Focus Test Beam of the Stanford Linear Accelerator Center, the fluorescence yield of 28.5 GeV electrons in air and nitrogen was measured. The measured photon yields between 300 and 400 nm at 1 atm and 29 C are Y(760 Torr){sup air} = 4.42 {+-} 0.73 and Y(760 Torr){sup N{sub 2}} = 29.2 {+-} 4.8 photons per electron per meter. Assuming that the fluorescence yield is proportional to the energy deposition of a charged particle traveling through air, good agreement with measurements at lower particle energies is observed.

  11. X-RAY FLUORESCENCE ANALYSIS OF HANFORD LOW ACTIVITY WASTE SIMULANTS METHOD DEVELOPMENT

    SciTech Connect (OSTI)

    Jurgensen, A; David Missimer, D; Ronny Rutherford, R

    2007-08-08T23:59:59.000Z

    The x-ray fluorescence laboratory (XRF) in the Analytical Development Directorate (ADD) of the Savannah River National Laboratory (SRNL) was requested to develop an x-ray fluorescence spectrometry method for elemental characterization of the Hanford Tank Waste Treatment and Immobilization Plant (WTP) pretreated low activity waste (LAW) stream to the LAW Vitrification Plant. The WTP is evaluating the potential for using XRF as a rapid turnaround technique to support LAW product compliance and glass former batching. The overall objective of this task was to develop an XRF analytical method that provides rapid turnaround time (<8 hours), while providing sufficient accuracy and precision to determine variations in waste.

  12. Three-dimensional x-ray fluorescence mapping of a gold nanoparticle-loaded phantom

    SciTech Connect (OSTI)

    Ren, Liqiang; Wu, Di; Li, Yuhua; Liu, Hong, E-mail: liu@ou.edu [Center for Bioengineering and School of Electrical and Computer Engineering, University of Oklahoma, Norman, Oklahoma 73019 (United States)] [Center for Bioengineering and School of Electrical and Computer Engineering, University of Oklahoma, Norman, Oklahoma 73019 (United States); Wang, Ge [Biomedical Imaging Cluster and Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States)] [Biomedical Imaging Cluster and Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States); Wu, Xizeng [Department of Radiology, University of Alabama, Birmingham, Alabama 35233 (United States)] [Department of Radiology, University of Alabama, Birmingham, Alabama 35233 (United States)

    2014-03-15T23:59:59.000Z

    Purpose : X-ray fluorescence (XRF) is a promising technique with sufficient specificity and sensitivity for identifying and quantifying features in small samples containing high atomic number (Z) materials such as iodine, gadolinium, and gold. In this study, the feasibility of applying XRF to early breast cancer diagnosis and treatment is studied using a novel approach for three-dimensional (3D) x-ray fluorescence mapping (XFM) of gold nanoparticle (GNP)-loaded objects in a physical phantom at the technical level. Methods : All the theoretical analysis and experiments are conducted under the condition of using x-ray pencil beam and a compactly integrated x-ray spectrometer. The penetrability of the fluorescence x-rays from GNPs is first investigated by adopting a combination of BR12 with 70 mm/50 mm in thickness on the excitation/emission path to mimic the possible position of tumor goldin vivo. Then, a physical phantom made of BR12 is designed to translate in 3D space with three precise linear stages and subsequently the step by step XFM scanning is performed. The experimental technique named as background subtraction is applied to isolate the gold fluorescence from each spectrum obtained by the spectrometer. Afterwards, the attenuations of both the incident primary x-ray beam with energies beyond the gold K-edge energy (80.725 keV) and the isolated gold K{sub ?} fluorescence x-rays (65.99 –69.80 keV) acquired after background subtraction are well calibrated, and finally the unattenuated K{sub ?} fluorescence counts are used to realize mapping reconstruction and to describe the linear relationship between gold fluorescence counts and corresponding concentration of gold solutions. Results : The penetration results show that the goldK{sub ?} fluorescence x-rays have sufficient penetrability for this phantom study, and the reconstructed mapping results indicate that both the spatial distribution and relative concentration of GNPs within the designed BR12 phantom can be well identified and quantified. Conclusions : Although the XFM method in this investigation is still studied at the technical level and is not yet practical for routinein vivo mapping tasks with GNPs, the current penetrability measurements and phantom study strongly suggest the feasibility to establish and develop a 3D XFM system.

  13. Fluorescence excitation enhancement by Bloch surface wave in all-polymer one-dimensional photonic structure

    SciTech Connect (OSTI)

    Fornasari, L.; Floris, F.; Patrini, M.; Guizzetti, G.; Marabelli, F., E-mail: franco.marabelli@unipv.it [Dipartimento di Fisica, Università degli Studi di Pavia, via Bassi 6, 27100 Pavia (Italy); Canazza, G.; Comoretto, D. [Dipartimento di Chimica e Chimica Industriale, Università degli Studi di Genova, via Dodecaneso 31, 16146 Genova (Italy)

    2014-08-04T23:59:59.000Z

    We demonstrate photoluminescence excitation enhancement in an all-polymer flexible one-dimensional photonic crystal structure capped with a fluorescent organic ultrathin film. When optical matching conditions between the excitation beam and the Bloch Surface Wave mode supported by the photonic structure are achieved, a ten times enhancement of the photoluminescence is observed. We notice that in these systems luminescence signal reinforcement is achieved by increasing the pump efficiency with no need of spectral resonance to the emission of the chosen fluorophore. All these features make these systems suitable candidates for easy, flexible, and cheap fluorescent sensing.

  14. A study of the relationships of self-efficacy of self-management of asthma and asthma self-management knowledge 

    E-Print Network [OSTI]

    McCorkle, Laura Steed

    2005-11-01T23:59:59.000Z

    The purposes of this study are to examine the relationship of self-efficacy regarding self-management of asthma and student self-management knowledge and also examine the extent to which self-efficacy and self-management ...

  15. Modeling green fluorescent protein transcription, translation and modification as a method to obtain NF-kappaB activation profiles

    E-Print Network [OSTI]

    Laible, Allyson Marie

    2009-05-15T23:59:59.000Z

    that fluorescence increases up to 24 hours after an initial delay of approximately four hours. The fluorescence data was also used to develop a model describing significant events leading to NF-?B activation and GFP expression. In addition, a model describing...

  16. First-Principles Characterization of the Energy Landscape and Optical Spectra of Green Fluorescent Protein along the AIB

    E-Print Network [OSTI]

    Krylov, Anna I.

    First-Principles Characterization of the Energy Landscape and Optical Spectra of Green Fluorescent Supporting Information ABSTRACT: Structures and optical spectra of the green fluorescent protein (GFP) forms-form) is lowest in energy, whereas the systems with the anionic chromophore (B- and I-forms) are about 1 kcal

  17. Proton Pathways in Green Fluorescence Protein Department of Physical Chemistry, The Hebrew University of Jerusalem, Jerusalem, Israel

    E-Print Network [OSTI]

    Agmon, Noam

    Proton Pathways in Green Fluorescence Protein Noam Agmon Department of Physical Chemistry, The Hebrew University of Jerusalem, Jerusalem, Israel ABSTRACT Proton pathways in green fluorescent protein pathway exists from the active site to the protein surface, controlled by a threonine switch. A proton

  18. Single-Molecule Fluorescence Studies of Protein Folding and Conformational Xavier Michalet,* Shimon Weiss, and Marcus Jager*

    E-Print Network [OSTI]

    Michalet, Xavier

    Single-Molecule Fluorescence Studies of Protein Folding and Conformational Dynamics Xavier Michalet. Single-Molecule Fluorescence Studies of Protein Folding and Conformations at Equilibrium 1796 4-Molecule Protein Folding under Nonequilibrium Conditions 1808 6. Conclusion 1809 7. Acknowledgments 1810 8

  19. Confocal X-ray Fluorescence (XRF) Microscopy: A New Technique for the Nondestructive Compositional Depth Profiling of Paintings

    E-Print Network [OSTI]

    Gruner, Sol M.

    #12;Confocal X-ray Fluorescence (XRF) Microscopy: A New Technique for the Nondestructive tools such as x-ray fluorescence (XRF) [4,5,6,7] and proton-induced x-ray emission (PIXE) [3,8,9] to address the problem of compositional depth profiling of paintings. One XRF method consists of deducing

  20. Comparison of Air Fluorescence and Ionization Measurements of E.M. Shower Depth Profiles: Test of a UHECR Detector Technique

    SciTech Connect (OSTI)

    Belz, J.; Cao, Z.; Huentemeyer, P.; Jui, C.C.H.; Martens, K.; Matthews, J.; Maestas, M.; Smith, J.; Sokolsky, P.; Springer, R.W.; Thomas, J.; Thomas, S.; /Utah U.; Chen,P.; Field, Clive; Hast, C.; Iverson, R.; Ng, J.S.T.; Odian, A.; Reil, K.; Vincke, H.; Walz, D.; /SLAC /Montana U. /Rutgers U., Piscataway /Taiwan, Natl. Taiwan U.; ,

    2005-10-07T23:59:59.000Z

    Measurements are reported on the fluorescence of air as a function of depth in electromagnetic showers initiated by bunches of 28.5 GeV electrons. The light yield is compared with the expected and observed depth profiles of ionization in the showers. It validates the use of atmospheric fluorescence profiles in measuring ultra high energy cosmic rays.

  1. Global analysis of Fo rster resonance energy transfer in live cells measured by fluorescence lifetime imaging microscopy exploiting

    E-Print Network [OSTI]

    van Stokkum, Ivo

    Global analysis of Fo¨ rster resonance energy transfer in live cells measured by fluorescence of Fo¨ rster resonance energy transfer (FRET) in live cells using the rise time of acceptor fluorescence those molecules that are involved in the energy-transfer process are monitored. This contrasts

  2. A Highly Selective Turn-On Colorimetric, Red Fluorescent Sensor for Detecting Mobile Zinc in Living Cells

    E-Print Network [OSTI]

    Du, Pingwu

    We describe ZRL1, a turn-on colorimetric and red fluorescent zinc ion sensor. The Zn2+-promoted ring opening of the rhodamine spirolactam ring in ZRL1 evokes a 220-fold fluorescence turn-on response. In aqueous media, ZRL1 ...

  3. Bioimaging 4 (1996) 93106. Printed in the UK Fluorescent dot counting in

    E-Print Network [OSTI]

    van Vliet, Lucas J.

    Bioimaging 4 (1996) 93­106. Printed in the UK Fluorescent dot counting in interphase cell nuclei allows the enumeration of chromosomal abnormalities in interphase cell nuclei. This process is called dot counting. To estimate the distribution of chromosomes per cell, a large number of cells have to be analysed

  4. APPLICATION OF TEMPORAL TEXTURE FEATURES TO AUTOMATED ANALYSIS OF PROTEIN SUBCELLULAR LOCATIONS IN TIME SERIES FLUORESCENCE

    E-Print Network [OSTI]

    Gordon, Geoffrey J.

    are in constant movement within the cell, we extended our studies to time series images, which contain both to identify a protein's subcellular location is to label it with fluorescent dye, take microscope images this last step. The automated approach is more objective and sensitive than visual examination, and single

  5. Red Fluorescent Protein pH Biosensor to Detect Concentrative Nucleoside Transport*S

    E-Print Network [OSTI]

    Campbell, Robert E.

    Red Fluorescent Protein pH Biosensor to Detect Concentrative Nucleoside Transport*S Received concentrative nucleoside transporter, hCNT3, medi- ates Na /nucleoside and H /nucleoside co-transport. We describe a new approach to monitor H /uridine co-transport in cultured mammalian cells, using a p

  6. A fluorescent assay for chloride transport; identification of a synthetic anionophore with improved activity

    E-Print Network [OSTI]

    Smith, Bradley D.

    A fluorescent assay for chloride transport; identification of a synthetic anionophore with improved on the chloride-sensitive probe, lucigenin, is developed for monitoring chloride transport into vesicles, and used to compare the effectiveness of three steroid- derived transporters. A topic of growing interest

  7. Understanding Blue-to-Red Conversion in Monomeric Fluorescent Timers and Hydrolytic Degradation of Their

    E-Print Network [OSTI]

    Verkhusha, Vladislav V.

    Understanding Blue-to-Red Conversion in Monomeric Fluorescent Timers and Hydrolytic Degradation-FT (chromophore Met66-Tyr67-Gly68) and its precursor with blocked blue-to- red conversion Blue102 (chromophore Leu data suggest that blue-to-red conversion, taking place in Fast-FT and in related FTs, is associated

  8. FLUORESCENCE AND FIBER-OPTICS BASED REAL-TIME THICKNESS SENSOR FOR DYNAMIC LIQUID FILMS

    E-Print Network [OSTI]

    Narain, Amitabh

    /analyzed the incident reflected waves to identify and measure the total transit time of the sound wave (of known wave-speed1 FLUORESCENCE AND FIBER-OPTICS BASED REAL-TIME THICKNESS SENSOR FOR DYNAMIC LIQUID FILMS T. W. Ng/disadvantages of many known liquid film thickness sensing devices (viz. conductivity probes, reflectance based fiber

  9. Laser-excited atomic fluorescence spectrometry in a graphite furnace with an

    E-Print Network [OSTI]

    Michel, Robert G.

    must provide high peak energy above sequentially with the analysis time determined primarilyLaser-excited atomic fluorescence spectrometry in a graphite furnace with an optical parametric for electrothermal atomic excited atomic ¯ uorescence spectrometry (LEAFS ) in a absorption spectrometry (ETAAS

  10. Accretion, fluorescent X-ray emission and flaring magnetic structures in YSOs

    E-Print Network [OSTI]

    F. Favata

    2004-12-20T23:59:59.000Z

    I present some recent developments on high-energy phenomena in YSOs, concentrating on the new evidence for accretion-induced X-ray emission in YSOs, for Fe 6.4 keV fluorescent emission from the disks of YSOs and for very long magnetic structures responsible for intense X-ray flares, likely connecting the star and the circumstellar disk.

  11. Improved fluorescence-enhanced optical imaging and tomography by enhanced excitation light rejection

    E-Print Network [OSTI]

    Hwang, Kil Dong

    2009-05-15T23:59:59.000Z

    match for tomographic reconstruction of one (1 cm3) and two (0.1 cm3) targets in a 1087 cm3 of breast phantom. Ultimately, this work improves the sensitivity of NIR fluorescence imaging by enhancing the rejection of excitation light and shows...

  12. Iron Fluorescent Line Emission from Young Stellar Objects in the Orion Nebula

    E-Print Network [OSTI]

    M. Tsujimoto; E. D. Feigelson; N. Grosso; G. Micela; Y. Tsuboi; F. Favata; H. Shang; J. H. Kastner

    2004-12-25T23:59:59.000Z

    We present the result of a systematic search for the iron Kalpha fluorescent line at 6.4 keV among 1616 X-ray sources detected by ultra-deep Chandra observations of the Orion Nebula Cluster and the obscured Orion Molecular Cloud 1 population as part of the Chandra Orion Ultra-deep Project (COUP). Seven sources are identified to have an excess emission at 6.4 keV among 127 control sample sources with significant counts in the 6.0-9.0 keV band. These seven sources are young stellar objects (YSOs) characterized by intense flare-like flux variations, thermal spectra, and near-infrared (NIR) counterparts. The observed equivalent widths of the line cannot be attributed to the fluorescence by interstellar or circumstellar matter along the line of sight. The X-ray spectral fits and NIR colors of the 6.4 keV sources show that these sources have X-ray absorption of > 1x10^22 cm^(-2) and NIR excess emission, which is not expected when the fluorescence occurs at the stellar photosphere. We therefore conclude that the iron fluorescent line of YSOs arises from reflection off of circumstellar disks, which are irradiated by the hard X-ray continuum emission of magnetic reconnection flares.

  13. Fluorescent probes for non-invasive bioenergetic studies of whole cyanobacterial cells

    E-Print Network [OSTI]

    Roegner, Matthias

    Fluorescent probes for non-invasive bioenergetic studies of whole cyanobacterial cells Markus of bioenergetic processes in whole cells of the cyanobacterium Synechocystis sp. PCC 6803. Acridine yellow to be created. In sum- mary, bioenergetic £uorescence measurement com- bines the advantages of an easy

  14. Fluorescence technique for on-line monitoring of state of hydrogen-producing microorganisms

    DOE Patents [OSTI]

    Seibert, Michael (Lakewood, CO); Makarova, Valeriya (Golden, CO); Tsygankov, Anatoly A. (Pushchino, RU); Rubin, Andrew B. (Moscow, RU)

    2007-06-12T23:59:59.000Z

    In situ fluorescence method to monitor state of sulfur-deprived algal culture's ability to produce H.sub.2 under sulfur depletion, comprising: a) providing sulfur-deprived algal culture; b) illuminating culture; c) measuring onset of H.sub.2 percentage in produced gas phase at multiple times to ascertain point immediately after anerobiosis to obtain H.sub.2 data as function of time; and d) determining any abrupt change in three in situ fluorescence parameters; i) increase in F.sub.t (steady-state level of chlorophyll fluorescence in light adapted cells); ii) decrease in F.sub.m', (maximal saturating light induced fluorescence level in light adapted cells); and iii) decrease in .DELTA.F/F.sub.m'=(F.sub.m'-F.sub.t)/F.sub.m' (calculated photochemical activity of photosystem II (PSII) signaling full reduction of plastoquinone pool between PSII and PSI, which indicates start of anaerobic conditions that induces synthesis of hydrogenase enzyme for subsequent H.sub.2 production that signal oxidation of plastoquinone pool asmain factor to regulate H.sub.2 under sulfur depletion.

  15. Subsurface contaminant monitoring by laser fluorescence excitation-emission spectroscopy in a cone penetrometer probe

    SciTech Connect (OSTI)

    Lin, J.; Hart, S.J.; Wang, W.; Namytchkine, D.; Kenny, J.E. [Tufts Univ., Medford, MA (United States). Dept. of Chemistry

    1995-12-31T23:59:59.000Z

    A laser-induced fluorescence (LIF) excitation-emission matrix (EEM) probe has been developed for subsurface monitoring of fluorescent organic contaminants. The fourth harmonic of a flashlamp-pumped Nd:YAG laser (at 266 nm) is used to pump a Raman shifter. Up to ten laser beams (in the wavelength region of 258 to 379 nm) from the Raman shifter are launched into optical fibers that conduct the light to the probe near the tip of the cone penetrometer. The fluorescence emission is excited through ten separate sapphire windows and collected by ten collection fibers that conduct the fluorescence to a spectrograph/CCD detection system. This probe allows real-time collection of LIF-EEMs of contaminants adsorbed on solids or dissolved in groundwater. LIF-EEMs provide a substantial amount of spectral information that can be used to determine the composition and quantity of contaminants in soils. The system was tested and calibrated in the laboratory. Spectra of different organic contaminants were measured in aqueous solutions, in organic solvents, and in different types of soils.

  16. Determination of hydrocarbons in sea water via UV-induced total fluorescence spectroscopy

    SciTech Connect (OSTI)

    Muroski, A.R.; Booksh, K.S.; Myrick, M.L. [Univ. of South Carolina, Columbia, SC (United States)

    1995-12-31T23:59:59.000Z

    The increasingly ubiquitous presence of anthropogenic hydrocarbons in oceans, lakes, and rivers necessitates the development of practical means of determining such pollutants in natural waters. Monitoring the subsurface progression and eventual fate of hydrocarbons from a particular source in the marine environment requires a technique amenable to rapid data acquisition and evaluation. Total UV fluorescence spectroscopy meets this requirement, while providing sufficient information in the excitation/emission matrix (EEM) for resolution of individual compounds in a complex aqueous mixture. The large amount of information available in an EEM can be made practical, however, only through the use of third-order statistical spectral analysis. Simultaneous excitation and collection of fluorescence at multiple wavelengths was accomplished using an imaging spectrofluorometer. Application of principal component analysis (PCA) to the resulting EEMs reveals the number of spectrally-distinct substances in oil/water mixtures. The contribution of each of these fluorophores to the matrix can then be determined by means of parallel factor analysis (PARAFAC), providing a solution which is unique for a particular component. Individual hydrocarbons, such as naphthalene - a major UV-fluorescent component of gasoline, have been determined at low ppb levels in sea water characterized by a fluorescence background produced by petroleum and humic acids.

  17. Metal-atom fluorescence from the quenching of metastable rare gases by metal carbonyls

    SciTech Connect (OSTI)

    Hollingsworth, W.E.

    1982-11-01T23:59:59.000Z

    A flowing afterglow apparatus was used to study the metal fluorescence resulting from the quenching of metastable rare-gas states by metal carbonyls. The data from the quenching or argon, neon, and helium by iron and nickel carbonyl agreed well with a restricted degree of freedom model indicating a concerted bond-breaking dissociation.

  18. Estimation of membrane lateral pressure in living cells by means of multidimensional confocal fluorescence microscopy

    E-Print Network [OSTI]

    Rosso, Lula

    -labeled phospholipids. We report an alternative strategy based on the intramolecular fluorescence energy transfer Kensington Campus, London SW7 2AZ, UK Considerable pressures (many tens of atmospheres) are generated within between the energy necessary to keep the hydrocarbon chains away from water and the energy generated

  19. Remote temperature measurements in femto-liter volumes using dual-focus-Fluorescence Correlation Spectroscopy

    E-Print Network [OSTI]

    Enderlein, Jörg

    Remote temperature measurements in femto-liter volumes using dual-focus-Fluorescence Correlation February 2009 DOI: 10.1039/b807910b Remote temperature measurements in microfluidic devices with micrometer for remote temperature measurements on a micrometer scale. We perform comparative temperature measurements

  20. A Microfluidic Device for Temporally Controlled Gene Expression and Long-Term Fluorescent Imaging in

    E-Print Network [OSTI]

    Siggia, Eric

    A Microfluidic Device for Temporally Controlled Gene Expression and Long-Term Fluorescent Imaging of the cell cycle. Over the past ten years, microfluidic techniques in cell biology have emerged that allow a microfluidic flow cell to grow Saccharomyces Cerevisiae for more than 8 generations (

  1. FOCUS www.rsc.org/loc | Lab on a Chip Improving fluorescence detection in lab on

    E-Print Network [OSTI]

    Fygenson, Deborah Kuchnir

    ) graft on glass. Two cell populations are separately labeled with live cell dyes and are mixed and seeded and sensitivity, due primarily to sub-optimal light collection. More sensi- tive, higher resolution LOC devices for performing high-sensitivity and high-resolution fluo- rescence detection within LOC devices. Fluorescence

  2. Single-molecule protein folding: Diffusion fluorescence resonance energy transfer studies

    E-Print Network [OSTI]

    Croquette, Vincent

    Single-molecule protein folding: Diffusion fluorescence resonance energy transfer studies for protein folding studies and has been extensively stud- ied, both experimentally (at the ensemble level concentration. It is shown that new infor- mation about different aspects of the protein folding reaction can

  3. Video-Rate Scanning Two-Photon Excitation Fluorescence Microscopy and Ratio Imaging with Cameleons

    E-Print Network [OSTI]

    Tsien, Roger Y.

    Video-Rate Scanning Two-Photon Excitation Fluorescence Microscopy and Ratio Imaging with Cameleons ABSTRACT A video-rate (30 frames/s) scanning two-photon excitation microscope has been successfully tested 690 to 1050 nm, prechirper optics for laser pulse-width compression, resonant galvanometer for video

  4. Large single-molecule fluorescence enhancements produced by a bowtie nanoantenna

    E-Print Network [OSTI]

    Fan, Shanhui

    Large single-molecule fluorescence enhancements produced by a bowtie nanoantenna Anika Kinkhabwala1, the highly enhanced optical fields of lithographically fabricated bowtie nanoantennas9 provide a structure that is more controllable and amenable to integration. Using gold bowties, we observe enhancements of a single

  5. Frequently Asked Questions Information on Compact Fluorescent Light Bulbs (CFLs) and Mercury

    E-Print Network [OSTI]

    Jia, Songtao

    Frequently Asked Questions Information on Compact Fluorescent Light Bulbs (CFLs) and Mercury February 2008 Why should people use CFLs? Switching from traditional light bulbs to CFLs is an effective light bulbs, last up to 10 times longer, cost little up front, and provide a quick return on investment

  6. Filter-fluorescer measurement of low-voltage simulator x-ray energy spectra

    SciTech Connect (OSTI)

    Baldwin, G.T.; Craven, R.E.

    1986-01-01T23:59:59.000Z

    X-ray energy spectra of the Maxwell Laboratories MBS and Physics International Pulserad 737 were measured using an eight-channel filter-fluorescer array. The PHOSCAT computer code was used to calculate channel response functions, and the UFO code to unfold spectrum.

  7. absorption laser-induced fluorescence: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    absorption laser-induced fluorescence First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Absolute...

  8. ISSUANCE 2015-06-17: Energy Conservation Standards for Fluorescent Lamp Ballasts, Notice of Public Meeting and Availability of the Framework Document

    Broader source: Energy.gov [DOE]

    Energy Conservation Standards for Fluorescent Lamp Ballasts, Notice of Public Meeting and Availability of the Framework Document

  9. The use of fluorescent intrabodies to detect endogenous gankyrin in living cancer cells

    SciTech Connect (OSTI)

    Rinaldi, Anne-Sophie; Freund, Guillaume; Desplancq, Dominique; Sibler, Annie-Paule; Baltzinger, Mireille [Ecole Supérieure de Biotechnologie de Strasbourg, UMR 7242, CNRS/Université de Strasbourg, boulevard Sébastien Brant, 67412 Illkirch (France); Rochel, Natacha [Institut de Génétique et de Biologie Moléculaire et Cellulaire, UMR 7104, CNRS/INSERM/Université de Strasbourg, rue Laurent Fries, 67404 Illkirch (France); Mély, Yves; Didier, Pascal [Faculté de Pharmacie, UMR 7213, CNRS/Université de Strasbourg, route du Rhin, 67401 Illkirch (France); Weiss, Etienne, E-mail: eweiss@unistra.fr [Ecole Supérieure de Biotechnologie de Strasbourg, UMR 7242, CNRS/Université de Strasbourg, boulevard Sébastien Brant, 67412 Illkirch (France)

    2013-04-01T23:59:59.000Z

    Expression of antibody fragments in mammalian cells (intrabodies) is used to probe the target protein or interfere with its biological function. We previously described the in vitro characterisation of a single-chain Fv (scFv) antibody fragment (F5) isolated from an intrabody library that binds to the oncoprotein gankyrin (GK) in solution. Here, we have isolated several other scFvs that interact with GK in the presence of F5 and tested whether they allow, when fused to fluorescent proteins, to detect by FRET endogenous GK in living cells. The binding of pairs of scFvs to GK was analysed by gel filtration and the ability of each scFv to mediate nuclear import/export of GK was determined. Binding between scFv-EGFP and RFP-labelled GK in living cells was detected by fluorescence lifetime imaging microscopy (FLIM). After co-transfection of two scFvs fused to EGFP and RFP, respectively, which form a tri-molecular complex with GK in vitro, FRET signal was measured. This system allowed us to observe that GK is monomeric and distributed throughout the cytoplasm and nucleus of several cancer cell lines. Our results show that pairs of fluorescently labelled intrabodies can be monitored by FLIM–FRET microscopy and that this technique allows the detection of lowly expressed endogenous proteins in single living cells. Highlights: ? Endogenous GK in living cells was targeted with pairs of fluorescently-tagged scFvs. ? Tri-molecular complexes containing two scFvs and one molecule GK were formed. ? GK was detected using fluorescence lifetime-based FRET imaging. ? GK is monomeric and homogeneously distributed in several cancer cell lines. ? This technique may have many applications in live-cell imaging of endogenous proteins.

  10. Recovery of yttrium from cathode ray tubes and lamps’ fluorescent powders: experimental results and economic simulation

    SciTech Connect (OSTI)

    Innocenzi, V., E-mail: valentina.innocenzi1@univaq.it; De Michelis, I.; Ferella, F.; Vegliò, F.

    2013-11-15T23:59:59.000Z

    Highlights: • Fluorescent powder of lamps. • Fluorescent powder of cathode ray rubes. • Recovery of yttrium from fluorescent powders. • Economic simulation for the processes to recover yttrium from WEEE. - Abstract: In this paper, yttrium recovery from fluorescent powder of lamps and cathode ray tubes (CRTs) is described. The process for treating these materials includes the following: (a) acid leaching, (b) purification of the leach liquors using sodium hydroxide and sodium sulfide, (c) precipitation of yttrium using oxalic acid, and (d) calcinations of oxalates for production of yttrium oxides. Experimental results have shown that process conditions necessary to purify the solutions and recover yttrium strongly depend on composition of the leach liquor, in other words, whether the powder comes from treatment of CRTs or lamp. In the optimal experimental conditions, the recoveries of yttrium oxide are about 95%, 55%, and 65% for CRT, lamps, and CRT/lamp mixture (called MIX) powders, respectively. The lower yields obtained during treatments of MIX and lamp powders are probably due to the co-precipitation of yttrium together with other metals contained in the lamps powder only. Yttrium loss can be reduced to minimum changing the experimental conditions with respect to the case of the CRT process. In any case, the purity of final products from CRT, lamps, and MIX is greater than 95%. Moreover, the possibility to treat simultaneously both CRT and lamp powders is very important and interesting from an industrial point of view since it could be possible to run a single plant treating fluorescent powder coming from two different electronic wastes.

  11. Strobe Light Deterrent Efficacy Test and Fish Behavior Determination at Grand Coulee Dam Third Powerplant Forebay

    SciTech Connect (OSTI)

    Simmons, Mary Ann; Johnson, Robert L.; McKinstry, Craig A.; Simmons, Carver S.; Cook, Chris B.; Brown, Richard S.; Tano, Daniel K.; Thorsten, Susan L.; Faber, Derrek M.; Lecaire, Richard; Francis, Stephen

    2004-01-01T23:59:59.000Z

    This report documents the third year of a four-year study to assess the efficacy of a prototype strobe light system to elicit a negative phototactic response in kokanee salmon (Oncorhynchus nerka) and rainbow trout (O. mykiss) in the forebay to the third powerplant at Grand Coulee Dam. This work was conducted for the Bonneville Power Administration, U.S. Department of Energy, by Pacific Northwest National Laboratory (PNNL) in conjunction with the Confederated Tribes of the Colville Reservation (Colville Confederated Tribes).

  12. Influence of Agricultural Dual Credit on Student College Readiness Self-Efficacy

    E-Print Network [OSTI]

    Neely, Alanna L.

    2013-07-12T23:59:59.000Z

    INFLUENCE OF AGRICULTURAL DUAL CREDIT ON STUDENT COLLEGE READINESS SELF-EFFICACY A Record of Study by ALANNA LEE NEELY Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements... should consider earning postsecondary degrees and credentials. The Completion Agenda states: This increased focus on college completion (not simply college access) is reflected in, for example, President Obama?s goal for the United States...

  13. Structured communication: effects on teaching efficacy of student teachers and student teacher - cooperating teacher relationships

    E-Print Network [OSTI]

    Edgar, Don Wayne

    2007-09-17T23:59:59.000Z

    STRUCTURED COMMUNICATION: EFFECTS ON TEACHING EFFICACY OF STUDENT TEACHERS AND STUDENT TEACHER – COOPERATING TEACHER RELATIONSHIPS A Dissertation by DON WAYNE EDGAR Submitted to the Office of Graduate Studies of Texas A... – COOPERATING TEACHER RELATIONSHIPS A Dissertation by DON WAYNE EDGAR Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Approved by: Co...

  14. Self-Efficacy of Early-Career Agricultural Science Teachers in Texas

    E-Print Network [OSTI]

    Carroll, Bodie

    2013-12-10T23:59:59.000Z

    in the classroom instruction domain (Edgar, Roberts, & Murphy, 2009; Roberts, Harlin, & Briers, 2008; Stripling, Ricketts, Roberts, & Harlin, 2008; Roberts, Mowen, Edgar, Harlin, & Briers, 2007; Harlin, Roberts, Briers, Mowen, & Edgar, 2007; Roberts, Harlin..., & Ricketts, 2006; Edgar, Roberts, & Murphy, 2011) Additionally, Burris, McLaughlin, McCullough, Brashears, & Fraze, (2010) conducted a study examining the differences in general efficacy among first and fifth year teachers. Roberts, Harlin, & Briers (2008...

  15. AN EMPIRICAL INVESTIGATION INTO THE MODERATING RELATIONSHIP OF COMPUTER SELF-EFFICACY ON PERFORMANCE IN A COMPUTER-SUPPORTED TASK

    E-Print Network [OSTI]

    Aguirre Urreta, Miguel Ignacio

    2008-01-01T23:59:59.000Z

    Computer Self-Efficacy has been shown to be a critical construct in a number of research areas within the Information Systems literature, most notably training, technology adoption, and performance in computer-related tasks. Attention has been...

  16. Teacher self-efficacy in Cape Town : a bottom up approach to enhancing the quality of education

    E-Print Network [OSTI]

    Kim, YeSeul

    2011-01-01T23:59:59.000Z

    Personal teacher self-efficacy (PTE), or the belief in one's own ability to overcome a particular challenge, often acts as a catalyst for teachers to improve the effectiveness of their teaching. Gaining PTE can translate ...

  17. Leadership behaviors and collective efficacy as perceived by teachers of schools in the Katy Independent School District

    E-Print Network [OSTI]

    Graham, Joe Wilson

    2007-09-17T23:59:59.000Z

    The primary purposes of this study were to discover any connections between leadership effectiveness and collective efficacy from campuses in the Katy Independent School District. It also was designed to discover other possible connections between...

  18. Baldrige Education Criteria for Performance Excellence: perceptions of district personnel of implementation and impact on collective teacher efficacy

    E-Print Network [OSTI]

    LeRoy, Kathryn A.

    2005-11-01T23:59:59.000Z

    The purpose of this study was to identify those elements of the Baldrige Education Criteria for Performance Excellence that central office leaders, principals, and teachers perceive as having an impact on collective teacher efficacy. The study...

  19. Treatment of exhaust fluorescent lamps to recover yttrium: Experimental and process analyses

    SciTech Connect (OSTI)

    De Michelis, Ida, E-mail: ida.demichelis@univaq.it [University of L'Aquila, Department of Chemistry, Chemical Engineering and Materials - Ex-Optimes Loc., Campo di Pile, 67100 L'Aquila (Italy); Ferella, Francesco, E-mail: francesco.ferella@univaq.it [University of L'Aquila, Department of Chemistry, Chemical Engineering and Materials - Ex-Optimes Loc., Campo di Pile, 67100 L'Aquila (Italy); Varelli, Ennio Fioravante [University of L'Aquila, Department of Chemistry, Chemical Engineering and Materials - Ex-Optimes Loc., Campo di Pile, 67100 L'Aquila (Italy); Veglio, Francesco, E-mail: francesco.veglio@univaq.it [University of L'Aquila, Department of Chemistry, Chemical Engineering and Materials - Ex-Optimes Loc., Campo di Pile, 67100 L'Aquila (Italy)

    2011-12-15T23:59:59.000Z

    Highlights: > Recovery of yttrium from spent fluorescent lamps by sulphuric acid leaching. > The use of sulphuric acid allows to reduce calcium dissolutions. > Main contaminant of fluorescent powder are Si, Pb, Ca and Ba. > Hydrated yttrium oxalate, recovered by selective precipitation, is quite pure (>90%). > We have studied the whole process for the treatment of dangerous waste (plant capability). - Abstract: The paper deals with recovery of yttrium from fluorescent powder coming from dismantling of spent fluorescent tubes. Metals are leached by using different acids (nitric, hydrochloric and sulphuric) and ammonia in different leaching tests. These tests show that ammonia is not suitable to recover yttrium, whereas HNO{sub 3} produces toxic vapours. A full factorial design is carried out with HCl and H{sub 2}SO{sub 4} to evaluate the influence of operating factors. HCl and H{sub 2}SO{sub 4} leaching systems give similar results in terms of yttrium extraction yield, but the last one allows to reduce calcium extraction with subsequent advantage during recovery of yttrium compounds in the downstream. The greatest extraction of yttrium is obtained by 20% w/v S/L ratio, 4 N H{sub 2}SO{sub 4} concentration and 90 deg. C. Yttrium and calcium yields are nearly 85% and 5%, respectively. The analysis of variance shows that acid concentration alone and interaction between acid and pulp density have a significant positive effect on yttrium solubilization for both HCl and H{sub 2}SO{sub 4} medium. Two models are empirically developed to estimate yttrium and calcium concentration during leaching. Precipitation tests demonstrate that at least the stoichiometric amount of oxalic acid is necessary to recover yttrium efficiently and a pure yttrium oxalate n-hydrate can be produced (99% grade). The process is economically feasible if other components of the fluorescent lamps (glass, ferrous and non-ferrous scraps) are recovered after the equipment dismantling and valorized, besides the cost that is usually paid to recycling companies for collection, treatment or final disposal of such fluorescent powders.

  20. Treatability study for removal of leachable mercury in crushed fluorescent lamps

    SciTech Connect (OSTI)

    Bostick, W.D.; Beck, D.E.; Bowser, K.T. [and others

    1996-02-01T23:59:59.000Z

    Nonserviceable fluorescent lamps removed from radiological control areas at the Oak Ridge Department of Energy facilities have been crushed and are currently managed as mixed waste (hazardous and radiologically contaminated). We present proposed treatment flowsheets and supporting treatability study data for conditioning this solid waste residue so that it can qualify for disposal in a sanitary landfill. Mercury in spent fluorescent lamps occurs primarily as condensate on high-surface-area phosphor material. It can be solubilized with excess oxidants (e.g., hypochlorite solution) and stabilized by complexation with halide ions. Soluble mercury in dechlorinated saline solution is effectively removed by cementation with zero-valent iron in the form of steel wool. In packed column dynamic flow testing, soluble mercury was reduced to mercury metal and insoluble calomel, loading > 1.2 g of mercury per grain of steel wool before an appreciable breakthrough of soluble mercury in the effluent.

  1. Laser-excited atomic fluorescence of atoms produced in a graphite furnace

    SciTech Connect (OSTI)

    Goforth, D.; Winefordner, J.D.

    1986-11-01T23:59:59.000Z

    Laser-excited atomic fluorescence in a graphite furnace gives detection limits for Pb, Cu, Mn, Sn, Al, In, Li, and Pt, in the picogram to sub-picogram range. The linear dynamic range for these elements varies from 3 to 7 orders of magnitude. A graphite rod, a plain graphite cup, and a slotted graphite cup are compared as the cuvette in the fluorescence system. Detection limits for a pyrolytic coating, a tantalum foil liner, and a tantalum carbide coating of the graphite cuvette are compared. A hydrogen-argon atmosphere, a low-pressure atmosphere, and an argon atmosphere are compared as the atmosphere surrounding the graphite cuvette. Lastly, Cu and Mn are determined in several standard reference materials.

  2. Enhanced-locality fiber-optic two-photon-fluorescence live-brain interrogation

    SciTech Connect (OSTI)

    Fedotov, I. V.; Doronina-Amitonova, L. V. [International Laser Center, Physics Department, M.V. Lomonosov Moscow State University, Moscow 119992 (Russian Federation); Russian Quantum Center, ul. Novaya 100, Skolkovo, Moscow Region 1430125 (Russian Federation); Kurchatov Institute National Research Center, Moscow (Russian Federation); Sidorov-Biryukov, D. A.; Fedotov, A. B. [International Laser Center, Physics Department, M.V. Lomonosov Moscow State University, Moscow 119992 (Russian Federation); Russian Quantum Center, ul. Novaya 100, Skolkovo, Moscow Region 1430125 (Russian Federation); Anokhin, K. V. [Kurchatov Institute National Research Center, Moscow (Russian Federation); P.K. Anokhin Institute of Normal Physiology, Russian Academy of Medical Sciences, Moscow (Russian Federation); Kilin, S. Ya. [B.I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, Minsk (Belarus); Sakoda, K. [National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044 (Japan); Zheltikov, A. M. [International Laser Center, Physics Department, M.V. Lomonosov Moscow State University, Moscow 119992 (Russian Federation); Russian Quantum Center, ul. Novaya 100, Skolkovo, Moscow Region 1430125 (Russian Federation); Department of Physics and Astronomy, Texas A and M University, College Station, Texas 77843 (United States); Center of Photochemistry, Russian Academy of Sciences, ul. Novatorov 7a, Moscow 117421 (Russian Federation)

    2014-02-24T23:59:59.000Z

    Two-photon excitation is shown to substantially enhance the locality of fiber-based optical interrogation of strongly scattering biotissues. In our experiments, a high-numerical-aperture, large-core-are fiber probe is used to deliver the 200-fs output of a 100-MHz mode-locked ytterbium fiber laser to samples of live mouse brain, induce two-photon fluorescence of nitrogen–vacancy centers in diamond markers in brain sample. Fiber probes with a high numerical aperture and a large core area are shown to enable locality enhancement in fiber-laser–fiber-probe two-photon brain excitation and interrogation without sacrificing the efficiency of fluorescence response collection.

  3. NIST energy related inventions: Electronic starter device for fluorescent lamps. Interim report, August--October, 1997

    SciTech Connect (OSTI)

    Johnson, S.A.

    1997-12-01T23:59:59.000Z

    From the Scope of Work document which accompanied the original proposal, three silicon devices were anticipated for development, simulation, and quality assurance fabrication. The status of these are in the same format as the Scope of Work...Attachment-A-: Task 1--design and simulation; Task 2--prototype tooling; Task 3--test engineering; Task 4--product tooling; Task 5--package tooling/manufacturing design and assembly. It is felt the program will meet it`s stated goals of producing a low cost, high performance fluorescent lamp starter which will lower the acquisition and operating cost of fluorescent technology...thus saving significant amounts of energy. The likelihood of success is even greater, now that the TN22 component has been qualified. The challenges of creating a custom ASIC, while still significant, are within the skill and expertise level or the assigned engineers.

  4. Laser induced fluorescence imaging of thermal damage in polymer matrix composites

    SciTech Connect (OSTI)

    Wachter, E.A.; Fisher, W.G.; Meyer, K.E.

    1996-12-31T23:59:59.000Z

    A simple, fluorescence-based imaging system was developed for identifying regions of thermal damage in polymer-matrix composites (PMCs). PMCs have important applications where low weight and high mechanical strength are needed. One concern in the aerospace industry is the tendency of some PMC materials to become irreversibly damaged when exposed to high temperatures. Traditional nondestructive evaluation (NDE) techniques are capable of detecting physical flaws, such as cracks and delaminations, but have not proven effective for detecting initial heat damage, which occurs on a molecular scale. Spectroscopic techniques such as laser-induced fluorescence provide an attractive means for detecting thermal damage on large, irregularly shaped surfaces. This paper describes instrumentation capable of rapidly detecting thermal damage in graphite/epoxy components.

  5. Dynamically Controlled Resonance Fluorescence from a Doubly Dressed Solid-State Single Emitter

    E-Print Network [OSTI]

    Yu He; Y. -M. He; J. Liu; Y. -J. Wei; H. Ramirez; M. Atatüre; C. Schneider; M. Kamp; S. Höfling; C. -Y. Lu; J. -W. Pan

    2014-11-22T23:59:59.000Z

    We report the first experimental demonstration of interference-induced spectral line elimination predicted by Zhu and Scully [Phys. Rev. Lett. 76, 388 (1996)] and Ficek and Rudolph [Phys. Rev. A 60, 4245 (1999)]. We drive an exciton transition of a self-assembled quantum dot in order to realize a two-level system exposed to bichromatic laser field and observe nearly complete elimination of the resonance fluorescence spectral line at the driving laser frequency. This is caused by quantum interference between coupled transitions among the doubly dressed excitonic states, without population trapping. We also demonstrate multiphoton ac Stark effect with shifted subharmonic resonances and dynamical modifications of resonance fluorescence spectra by using double dressing.

  6. Femtosecond lasing from a fluorescent protein in a one dimensional random cavity

    E-Print Network [OSTI]

    Drane, T M; Shapiro, M; Milner, V

    2015-01-01T23:59:59.000Z

    We present evidence of ultrafast random lasing from the fluorescent protein DsRed2 embedded in a random one-dimensional cavity. Lasing is achieved when a purified protein solution, placed inside a layered random medium, is optically excited with a femtosecond pump pulse in the direction perpendicular to the plane of random layers. We demonstrate that pumping with ultrashort pulses resulted in a lasing threshold two orders of magnitude lower than that found for nanosecond excitation.

  7. A Fluorescent Aerogel for Capture and Identification of Interplanetary and Interstellar Dust

    E-Print Network [OSTI]

    Gerardo Dominguez; Andrew J. Westphal; Mark L. F. Phillips; Steven M. Jones

    2003-03-27T23:59:59.000Z

    Contemporary interstellar dust has never been analyzed in the laboratory, despite its obvious astronomical importance and its potential as a probe of stellar nucleosynthesis and galactic chemical evolution. Here we report the discovery of a novel fluorescent aerogel which is capable of capturing hypervelocity dust grains and passively recording their kinetic energies. An array of these "calorimetric" aerogel collectors in low earth orbit would lead to the capture and identification of large numbers of interstellar dust grains.

  8. 2015-01-28 Issuance: Test Procedure for Fluorescent Lamp Ballasts; Final Rule Correction

    Broader source: Energy.gov [DOE]

    This document is a pre-publication Federal Register final rule correction regarding test procedures for fluorescent lamp ballasts, as issued by the Deputy Assistant Secretary for Energy Efficiency on January 28, 2014. Though it is not intended or expected, should any discrepancy occur between the document posted here and the document published in the Federal Register, the Federal Register publication controls. This document is being made available through the Internet solely as a means to facilitate the public's access to this document.

  9. Evaluation of Portable X-Ray Fluorescence (XRF) Analyzer for Zirconium-Thickness Measurements

    SciTech Connect (OSTI)

    Glenn Moore

    2013-09-01T23:59:59.000Z

    This Technical Evaluation Report provides details of preliminary testing/experiments performed using a handheld X-ray fluorescence analyzer. The analyzer will be utilized in upcoming fuel-foil-rolling optimization studies at the INL. The studies are being performed in support of DOE’s Office of Global Threat Reduction -- Reactor Conversion Subprogram. Details of the equipment used, operating parameters, and measurement results are provided in this report.

  10. Precise Measurement of the Absolute Yield of Fluorescence Photons in Atmospheric Gases

    SciTech Connect (OSTI)

    Ave, M.; /Karlsruhe, Inst. Technol.; Bohacova, M.; /Chicago U., EFI; Daumiller, K.; /Karlsruhe, Inst. Technol.; Di Carlo, P.; /INFN, Aquila; Di Giulio, C.; /INFN, Rome; Luis, P.Facal San; /Chicago U., EFI; Gonzales, D.; /Karlsruhe U., EKP; Hojvat, C.; /Fermilab; Horandel, J.R.; /Nijmegen U., IMAPP; Hrabovsky, M.; /Palacky U.; Iarlori, M.; /INFN, Aquila /Karlsruhe, Inst. Technol.

    2011-01-01T23:59:59.000Z

    We have performed a measurement of the absolute yield of fluorescence photons at the Fermilab Test Beam. A systematic uncertainty at 5% level was achieved by the use of Cherenkov radiation as a reference calibration light source. A cross-check was performed by an independent calibration using a laser light source. A significant improvement on the energy scale uncertainty of Ultra-High Energy Cosmic Rays is expected.

  11. Development of a radiative transport based, fluorescence-enhanced, frequency-domain small animal imaging system

    E-Print Network [OSTI]

    Rasmussen, John C.

    2009-05-15T23:59:59.000Z

    Dissertation by JOHN C. RASMUSSEN Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Approved by: Chair of Committee, Eva M. Sevick...-Enhanced, Frequency-Domain Small Animal Imaging System. (December 2006) John C. Rasmussen, B.S., University of Oklahoma Chair of Advisory Committee: Dr. Eva M. Sevick-Muraca Herein we present the development of a fluorescence-enhanced, frequency- domain radiative...

  12. Simulation of air shower image in fluorescence light based on energy deposits derived from CORSIKA

    E-Print Network [OSTI]

    D. Gora; D. Heck; P. Homola; H. Klages; J. Pekala; M. Risse; B. Wilczynska; H. Wilczynski

    2004-03-01T23:59:59.000Z

    Spatial distributions of energy deposited by an extensive air shower in the atmosphere through ionization, as obtained from the CORSIKA simulation program, are used to find the fluorescence light distribution in the optical image of the shower. The shower image derived in this way is somewhat smaller than that obtained from the NKG lateral distribution of particles in the shower. The size of the image shows a small dependence on the primary particle type.

  13. The measurement of delayed fluorescence in an acrylic based scintillation detector

    E-Print Network [OSTI]

    Hong, Chi-Ho

    1987-01-01T23:59:59.000Z

    University, Seoul, Korea Chairman of Advisory Committee: Dr. Robert C. Webb The measurement of delayed fluorescence in an acrylic based scintillation detector using cosmic ray muons has been performed. This apparatus measures both pulse height and time... based upon CCD (charge coupled device) and waveform digitizer. This apparatus allows us to study prompt as well as slowly developing pulses from the detector consisting of a block of acrylic based scintillator coupled directly to a photomultiplier...

  14. Luminescent studies of fluorescent chromophore-doped silica aerogels for flat panel display applications

    SciTech Connect (OSTI)

    Glauser, S.A.C. [California Univ., Davis, CA (United States). Dept. of Applied Science; Lee, H.W.H. [Lawrence Livermore National Lab., CA (United States)

    1997-04-01T23:59:59.000Z

    The remarkable optical and electronic properties of doped and undoped silica aerogels establish their utility as unique, mulitfunctional host materials for fluorescent dyes and other luminescent materials for display and imaging applications. We present results on the photoluminescence, absorption, and photoluminescence excitation spectra of undoped silica aerogels and aerogels doped with Er{sup 3+}, rhodamine 6G (R6G), and fluorescein. 4 refs., 12 figs.

  15. Fluorimetric determination of non-fluorescent dinitroaniline derivative herbicides, using the photoreduction of anthraquinone - 2,6-disulfonate

    SciTech Connect (OSTI)

    Traore, S.; Aaron, J.J.

    1987-12-01T23:59:59.000Z

    A photoreduction - fluorescence technique has been developed for the quantitative analysis of several dinitroaniline derivative herbicides. The photoreduction of anthraquinone-2,6-disulfonate by dinitroanilines generates highly fluorescent dihydroxyanthracene-2,6-disulfonate, in a 20 : 80 vol/vol acetonitrile-water mixture at room temperature. Optimal irradiation times for obtaining a convenient, sensitized fluorescence signal are relatively short, ranging between 2 and 4 min. Linear log-log calibration curves are established over several orders of magnitude in concentration units. The limits of detection range between 0.3 and 4.2 ..mu..g ml/sup -1/. The photoreduction-fluorescence technique is shown to be very convenient, sensitive, and precise for the quantitation of dinitroaniline herbicides.

  16. Fluorescence relaxation dynamics of CdSe and CdSe/CdS core/shell quantum dots

    SciTech Connect (OSTI)

    Kaur, Gurvir; Kaur, Harmandeep [Centre of Advanced Study in Physics, Department of Physics, Panjab University, Chandigarh-160014 (India); Tripathi, S. K., E-mail: surya@pu.ac.in [Centre of Advanced Study in Physics, Panjab University, Chandigarh- 160014 (India)

    2014-04-24T23:59:59.000Z

    Time-resolved fluorescence spectra for colloidal CdSe and CdSe/CdS core/shell quantum dots have been investigated to know their electron relaxation dynamics at the maximum steady state fluorescence intensity. CdSe core and CdSe/CdS type I core-shell materials with different shell (CdS) thicknesses have been synthesized using mercaptoacetic acid as a capping agent. Steady state absorption and emission studies confirmed successful synthesis of CdSe and CdSe/CdS core-shell quantum dots. The fluorescence shows a tri-exponential decay with lifetimes 57.39, 7.82 and 0.96 ns for CdSe quantum dots. The lifetime of each recombination decreased with growth of CdS shell over the CdSe core, with maximum contribution to fluorescence by the fastest transition.

  17. Fluorescence quenching by photoinduced electron transfer in the Zn[superscript 2+] sensor Zinpyr-1: a computational investigation

    E-Print Network [OSTI]

    Kowalczyk, Timothy Daniel

    We report a detailed study of luminescence switching in the fluorescent zinc sensor Zinpyr-1 by density functional methods. A two-pronged approach employing both time-dependent density functional theory (TDDFT) and constrained ...

  18. Fluorescence enhanced optical tomography on breast phantoms with measurements using a gain modulated intensified CCD imaging system

    E-Print Network [OSTI]

    Godavarty, Anuradha

    2005-08-29T23:59:59.000Z

    Fluorescence-enhanced optical imaging using near-infrared (NIR) light developed for in-vivo molecular targeting and reporting of cancer provides promising opportunities for diagnostic imaging. However, prior to the administration of unproven...

  19. Measurement of gas density and temperature distributions in strongly rotating UF/sub 6/ using laser-induced fluorescence

    SciTech Connect (OSTI)

    Gentry, R.A.; Caldwell, S.E.; White, R.W.

    1981-01-01T23:59:59.000Z

    A new technique for using Laser Induced Fluorescence (LIF) signals to measure the distribution of gas density and temperature in strongly rotating UF/sub 6/ gas is presented. An external pulsed laser is used to excite the rotating UF/sub 6/ gas, producing an exponentially decaying fluorescence signal. A multi-channel fiber optics system simultaneously collects the fluorescence signals emanating from a number of points in the gas. The signals from each optical channel are digitized and processed to determine the fluorescence signal intensity and decay lifetime at each of the points of observation by means of a least squares fitting process. Gas densities and temperatures are then determined from the intensity and lifetime data. A recently constructed LIF probe system is described and an analysis of the unfolding techniques necessary to process the signal data is presented. Preliminary data, obtained in tests of the probe system in a laboratory rotor, are presented.

  20. TESTING OF ENERGY CONSERVATION OF ELECTRONIC BALLASTS FOR FLUORESCENT LIGHTING REVIEW OF RECENT RESULTS AND RECOMMENDATIONS FOR DESIGN GOALS

    E-Print Network [OSTI]

    Verderber, R.R.

    2011-01-01T23:59:59.000Z

    Ur:.V(. ,(lh. Fluorescent Lighting Review of Recent Resultsfrom 30 0 C to 50°C. The lighting system.with core ballastswas conducted to measure the lighting system performance for

  1. Increasing proliferation resistance of sodium fast reactor fuel cycle through use of a nuclear resonance fluorescence detector

    E-Print Network [OSTI]

    Smith, David Ballin

    2010-01-01T23:59:59.000Z

    The proliferation resistance of a reprocessing facility can be improved by using a novel detection system that utilizes the nuclear resonance fluorescence (NRF) phenomenon to determine the isotopic composition of materials ...

  2. Use of 2-Aminopurine Fluorescence as a probe of DNA and computational studies of a new class of base analogues 

    E-Print Network [OSTI]

    Wu, Xiaohua

    2012-06-22T23:59:59.000Z

    The steady-state and time-resolved fluorescence of 2-aminopurine (2AP) have been used to monitor base dynamics and base stacking interactions in DNA single strands and dinucleotides, and to investigate the interactions ...

  3. Turn-on fluorescence in tetraphenylethylene-based metal-organic frameworks: An alternative to aggregation-induced emission

    E-Print Network [OSTI]

    Shustova, Natalia B.

    Coordinative immobilization of functionalized tetraphenylethylene within rigid porous metal–organic frameworks (MOFs) turns on fluorescence in the typically non-emissive tetraphenylethylene core. The matrix coordination-induced ...

  4. Critical tonicity determination of sperm using fluorescent staining and flow cytometry

    SciTech Connect (OSTI)

    Noiles, E.E.; Ruffing, N.A.; Kleinhans, F.W.; Mark, L.A.; Watson, P.F.; Critser, J.K. (Methodist Hospital, Indianapolis, IN (USA)); Horstman, L. (Purdue Univ., Lafayette, IN (USA). School of Veterinary Medicine); Mazur, P. (Oak Ridge National Lab., TN (USA))

    1990-01-01T23:59:59.000Z

    The use of cryopreserved, rather than fresh, mammalian semen for artificial insemination confers several important medical and/or economic advantages. However, current methods for cryopreservation of both human and bovine spermatozoa result in approximately only a 50% survival rate with thawing, obviously reducing the fertilizing capacity of the semen. A primary consideration during the cooling process is to avoid intracellular ice crystal formation with its lethal consequences to the cell. Current techniques achieve this by controlling the cooling rate. Computation of the time necessary for this dehydration, and hence, the cooling rate, is dependent upon knowledge of the water permeability coefficient (L{sub {rho}}) and its activation energy. The fluorophore, 6-carboxyfluoroscein diacetate (CFDA), which is nonfluorescent, readily crosses the intact plasma membrane. Intracellular esterases hydrolyze CFDA to 6-carboxyfluoroscein, a fluorescent, membrane-impermeable fluorophore. Consequently, spermatozoa with intact plasma membranes fluoresce bright green (Garner et. al., 1986), but those with disrupted membranes do not. Therefore, the purpose of this study was to use loss of CFDA fluorescence to determine the osmolality at which 50% of the spermatozoa will swell and lyse (critical tonicity, CT). These data will then be used to determine the L{sub {rho}} and its activation energy for sperm, thus increasing the knowledge available in cellular cryopreservation. 15 refs., 3 figs.

  5. Development of magnetic luminescent core/shell nanocomplex particles with fluorescence using Rhodamine 6G

    SciTech Connect (OSTI)

    Lee, Hee Uk; Song, Yoon Seok [Department of Chemical and Biological Engineering, Korea University, 5 Ga, Anam-Dong, Sungbuk-Gu, Seoul 136-701 (Korea, Republic of)] [Department of Chemical and Biological Engineering, Korea University, 5 Ga, Anam-Dong, Sungbuk-Gu, Seoul 136-701 (Korea, Republic of); Park, Chulhwan [Department of Chemical Engineering, Kwangwoon University, 447-1 Wolgye-Dong, Nowon-Gu, Seoul 139-701 (Korea, Republic of)] [Department of Chemical Engineering, Kwangwoon University, 447-1 Wolgye-Dong, Nowon-Gu, Seoul 139-701 (Korea, Republic of); Kim, Seung Wook, E-mail: kimsw@korea.ac.kr [Department of Chemical and Biological Engineering, Korea University, 5 Ga, Anam-Dong, Sungbuk-Gu, Seoul 136-701 (Korea, Republic of)

    2012-12-15T23:59:59.000Z

    Graphical abstract: Display Omitted Highlights: ? A simple method was developed to synthesize Co-B/SiO{sub 2}/dye/SiO{sub 2} composite particles. ? The magnetic particle shows that highly luminescent and core/shell particles are formed. ? Such core/shell particles can be easily suspended in water. ? The magnetic particles could detect fluorescence for the application of biosensor. -- Abstract: A simple and reproducible method was developed to synthesize a novel class of Co-B/SiO{sub 2}/dye/SiO{sub 2} composite core/shell particles. Using a single cobalt core, Rhodamine 6G of organic dye molecules was entrapped in a silica shell, resulting in core/shell particles of ?200 nm diameter. Analyses using a variety of techniques such as transmission electron microscopy, X-ray photoelectron spectroscopy, vibration sample magnetometry, confocal laser scanning microscopy, and fluorescence intensity demonstrated that dye molecules were trapped inside the core/shell particles. A photoluminescence investigation showed that highly luminescent and photostable core/shell particles were formed. Such core/shell particles can be easily suspended in water. The synthesized magnetic particles could be used to detect fluorescence on glass substrate arrays for bioassay and biosensor applications.

  6. The Fluorescence Detector of the Pierre Auger Observatory - a Calorimeter for UHECR

    SciTech Connect (OSTI)

    Keilhauer, B. [Universitaet Karlsruhe, Institut fuer Experimentelle Kernphysik, Postfach 3640, 76021 Karlsruhe (Germany); Observatorio Pierre Auger, Av. San Martin Norte 304, 5613 Malarguee (Argentina)

    2006-10-27T23:59:59.000Z

    The Pierre Auger Observatory is a hybrid detector for ultrahigh energy cosmic rays (UHECR) with energies above 1018.5 eV. Currently the first part of the Observatory nears completion in the southern hemisphere in Argentina. One detection technique uses over 1600 water Cherenkov tanks at ground where samples of secondary particles of extensive air showers (EAS) are detected. The second technique is a calorimetric measurement of the energy deposited by EAS in the atmosphere. Charged secondary particles of EAS lose part of their energy in the atmosphere via ionization. The deposited energy is converted into excitation of molecules of the air and afterwards partly emitted as fluorescence light mainly from nitrogen in the wavelength region between 300 and 400 nm. This light is observed with 24 fluorescence telescopes in 4 stations placed at the boundary of the surface array. This setup provides a combined measurement of the longitudinal shower development and the lateral particle distribution at ground of the same event. Details on the fluorescence technique and the necessary atmospheric monitoring will be presented, as well as first physics results on UHECR.

  7. Split green fluorescent protein as a modular binding partner for protein crystallization

    SciTech Connect (OSTI)

    Nguyen, Hau B. [Los Alamos National Laboratory, MS M888, Los Alamos, NM 87545 (United States); Hung, Li-Wei [Los Alamos National Laboratory, MS D454, Los Alamos, NM 87545 (United States); Yeates, Todd O. [University of California, PO Box 951569, Los Angeles, CA 90095 (United States); Terwilliger, Thomas C., E-mail: terwilliger@lanl.gov; Waldo, Geoffrey S., E-mail: terwilliger@lanl.gov [Los Alamos National Laboratory, MS M888, Los Alamos, NM 87545 (United States)

    2013-12-01T23:59:59.000Z

    A strategy using a new split green fluorescent protein (GFP) as a modular binding partner to form stable protein complexes with a target protein is presented. The modular split GFP may open the way to rapidly creating crystallization variants. A modular strategy for protein crystallization using split green fluorescent protein (GFP) as a crystallization partner is demonstrated. Insertion of a hairpin containing GFP ?-strands 10 and 11 into a surface loop of a target protein provides two chain crossings between the target and the reconstituted GFP compared with the single connection afforded by terminal GFP fusions. This strategy was tested by inserting this hairpin into a loop of another fluorescent protein, sfCherry. The crystal structure of the sfCherry-GFP(10–11) hairpin in complex with GFP(1–9) was determined at a resolution of 2.6 Å. Analysis of the complex shows that the reconstituted GFP is attached to the target protein (sfCherry) in a structurally ordered way. This work opens the way to rapidly creating crystallization variants by reconstituting a target protein bearing the GFP(10–11) hairpin with a variety of GFP(1–9) mutants engineered for favorable crystallization.

  8. Acceptance of fluorescence detectors and its implication in energy spectrum inference at the highest energies

    E-Print Network [OSTI]

    Vitor de Souza; Gustavo Medina-Tanco; Jeferson A. Ortiz

    2005-09-20T23:59:59.000Z

    Along the years HiRes and AGASA experiments have explored the fluorescence and the ground array experimental techniques to measure extensive air showers, being both essential to investigate the ultra-high energy cosmic rays. However, such Collaborations have published contradictory energy spectra for energies above the GZK cut-off. In this article, we investigate the acceptance of fluorescence telescopes to different primary particles at the highest energies. Using CORSIKA and CONEX shower simulations without and with the new pre-showering scheme, which allows photons to interact in the Earth magnetic field, we estimate the aperture of the HiRes-I telescope for gammas, iron nuclei and protons primaries as a function of the number of simulated events and primary energy. We also investigate the possibility that systematic differences in shower development for hadrons and gammas could mask or distort vital features of the cosmic ray energy spectrum at energies above the photo-pion production threshold. The impact of these effects on the true acceptance of a fluorescence detector is analyzed in the context of top-down production models.

  9. Portable total reflection x-ray fluorescence analysis in the identification of unknown laboratory hazards

    SciTech Connect (OSTI)

    Liu, Ying, E-mail: liu.ying.48r@st.kyoto-u.ac.jp; Imashuku, Susumu; Sasaki, Nobuharu; Ze, Long; Kawai, Jun [Department of Materials Science and Engineering, Kyoto University, Yoshida-Honmachi, Sakyo-ku, Kyoto 606-8501 (Japan); Takano, Shotaro; Sohrin, Yoshiki [Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan); Seki, Hiroko; Miyauchi, Hiroya [Kyoto Prefectural Technology Center for Small and Medium Enterprises, Chudojiminami machi, Shimogyo-ku, Kyoto 600-8813 (Japan)

    2014-05-15T23:59:59.000Z

    In this study, a portable total reflection x-ray fluorescence (TXRF) spectrometer was used to analyze unknown laboratory hazards that precipitated on exterior surfaces of cooling pipes and fume hood pipes in chemical laboratories. With the aim to examine the accuracy of TXRF analysis for the determination of elemental composition, analytical results were compared with those of wavelength-dispersive x-ray fluorescence spectrometry, scanning electron microscope and energy-dispersive x-ray spectrometry, energy-dispersive x-ray fluorescence spectrometry, inductively coupled plasma atomic emission spectrometry, x-ray diffraction spectrometry (XRD), and x-ray photoelectron spectroscopy (XPS). Detailed comparison of data confirmed that the TXRF method itself was not sufficient to determine all the elements (Z?>?11) contained in the samples. In addition, results suggest that XRD should be combined with XPS in order to accurately determine compound composition. This study demonstrates that at least two analytical methods should be used in order to analyze the composition of unknown real samples.

  10. A method of measuring gold nanoparticle concentrations by x-ray fluorescence for biomedical applications

    SciTech Connect (OSTI)

    Wu Di; Li Yuhua; Wong, Molly D.; Liu Hong [Center for Bioengineering and School of Electrical and Computer Engineering, University of Oklahoma, Norman, Oklahoma 73019 (United States)

    2013-05-15T23:59:59.000Z

    Purpose: This paper reports a technique that enables the quantitative determination of the concentration of gold nanoparticles (GNPs) through the accurate detection of their fluorescence radiation in the diagnostic x-ray spectrum. Methods: Experimentally, x-ray fluorescence spectra of 1.9 and 15 nm GNP solutions are measured using an x-ray spectrometer, individually and within chicken breast tissue samples. An optimal combination of excitation and emission filters is determined to segregate the fluorescence spectra at 66.99 and 68.80 keV from the background scattering. A roadmap method is developed that subtracts the scattered radiation (acquired before the insertion of GNP solutions) from the signal radiation acquired after the GNP solutions are inserted. Results: The methods effectively minimize the background scattering in the spectrum measurements, showing linear relationships between GNP solutions from 0.1% to 10% weight concentration and from 0.1% to 1.0% weight concentration inside a chicken breast tissue sample. Conclusions: The investigation demonstrated the potential of imaging gold nanoparticles quantitatively in vivo for in-tissue studies, but future studies will be needed to investigate the ability to apply this method to clinical applications.

  11. H_2 Absorption and Fluorescence for Gamma Ray Bursts in Molecular Clouds

    E-Print Network [OSTI]

    B. T. Draine

    1999-07-16T23:59:59.000Z

    If a gamma ray burst with strong UV emission occurs in a molecular cloud, there will be observable consequences resulting from excitation of the surrounding H2. The UV pulse from the GRB will pump H2 into vibrationally-excited levels which produce strong absorption at wavelengths < 1650 A. As a result, both the prompt flash and later afterglow will exhibit strong absorption shortward of 1650 A, with specific spectroscopic features. Such a cutoff in the emission from GRB 980329 may already have been observed by Fruchter et al.; if so, GRB 980329 was at redshift 3.0 < z < 4.4 . BVRI photometry of GRB 990510 could also be explained by H2 absorption if GRB 990510 is at redshift 1.6 < z < 2.3. The fluorescence accompanying the UV pumping of the H2 will result in UV emission from the GRB which can extend over days or months, depending on parameters of the ambient medium and beaming of the GRB flash. The 7.5-13.6 eV fluorescent luminosity is \\sim 10^{41.7} erg/s for standard estimates of the parameters of the GRB and the ambient medium. Spectroscopy can distinguish this fluorescent emission from other possible sources of transient optical emission, such as a supernova.

  12. Spatial assessment of net mercury emissions from the use of fluorescent bulbs

    SciTech Connect (OSTI)

    Matthew J. Eckelman; Paul T. Anastas; Julie B. Zimmerman [Yale University, New Haven, CT (United States). Department of Chemical Engineering

    2008-11-15T23:59:59.000Z

    While fluorescent lighting is an important technology for reducing electrical energy demand, mercury used in the bulbs is an ongoing concern. Using state and country level data, net emissions of mercury from the marginal use of fluorescent lightbulbs are examined for a base year of 2004 for each of the 50 United States and 130 countries. Combustion of coal for electric power generation is generally the largest source of atmospheric mercury pollution; reduction in electricity demand from the substitution of incandescent bulbs with fluorescents leads to reduced mercury emissions during the use of the bulb. This analysis considers the local mix of power sources, coal quality, thermal conversion efficiencies, distribution losses, and any mercury control technologies that might be in place. Emissions of mercury from production and end-of-life treatment of the bulbs are also considered, providing a life-cycle perspective. Net reductions in mercury over the entire life cycle range from -1.2 to 97 mg per bulb depending on the country. The consequences for atmospheric mercury emissions of several policy scenarios are also discussed. 46 refs., 4 figs., 3 tabs.

  13. Development of laser excited atomic fluorescence and ionization methods. Final technical progress report, May 1, 1988--December 31, 1991

    SciTech Connect (OSTI)

    Winefordner, J.D.

    1991-12-31T23:59:59.000Z

    Progress report: May 1, 1988 to December 31, 1991. The research supported by DE-FG05-88ER13881 during the past (nearly) 3 years can be divided into the following four categories: (1) theoretical considerations of the ultimate detection powers of laser fluorescence and laser ionization methods; (2) experimental evaluation of laser excited atomic fluorescence; (3) fundamental studies of atomic and molecular parameters in flames and plasmas; (4) other studies.

  14. Determination of the transport and change in composition of fluorescent materials in hydrologic systems by use of EEM spectroscopy

    SciTech Connect (OSTI)

    Goldberg, M.C. (Geological Survey, Lakewood, CO (USA))

    1990-01-01T23:59:59.000Z

    EEM spectra are sufficiently selective to allow fluorescence pattern characterization of the organic load of a river at a given location and to follow, qualitatively, the changes that ensue in that load as it moves in the river. By comparing the patterns of the load to specific materials such as illustrated by the Suwannee River pattern, humic acid fraction, comparison; it is possible to label major fluorescing components and to discern their appearance and disappearance as a function of location.

  15. Recovery of yttrium from fluorescent powder of cathode ray tube, CRT: Zn removal by sulphide precipitation

    SciTech Connect (OSTI)

    Innocenzi, Valentina, E-mail: valentina.innocenzi1@univaq.it [Department of Industrial Engineering and Information and Economy, University of L’Aquila, Via Giovanni Gronchi n.18, Nucleo Ind.le di Pile, 67100 L’Aquila (Italy); De Michelis, Ida; Ferella, Francesco [Department of Industrial Engineering and Information and Economy, University of L’Aquila, Via Giovanni Gronchi n.18, Nucleo Ind.le di Pile, 67100 L’Aquila (Italy); Beolchini, Francesca [Department of Marine Sciences, Polytechnic Institute of Marche, Via Brecce Bianche, 60131 Ancona (Italy); Kopacek, Bernd [SAT, Austrian Society for Systems Engineering and Automation, Gurkasse 43/2, A-1140 Vienna (Austria); Vegliò, Francesco [Department of Industrial Engineering and Information and Economy, University of L’Aquila, Via Giovanni Gronchi n.18, Nucleo Ind.le di Pile, 67100 L’Aquila (Italy)

    2013-11-15T23:59:59.000Z

    Highlights: • Treatment of fluorescent powder of CRT waste. • Factorial experimental designs to study acid leaching of fluorescent powder and the purification of leach liquors. • Recover of yttrium by precipitation using oxalic acid. • Suitable flowsheet to recover yttrium from fluorescent powder. - Abstract: This work is focused on the recovery of yttrium and zinc from fluorescent powder of cathode ray tube (CRT). Metals are extracted by sulphuric acid in the presence of hydrogen peroxide. Leaching tests are carried out according to a 2{sup 2} full factorial plan and the highest extraction yields for yttrium and zinc equal to 100% are observed under the following conditions: 3 M of sulphuric acid, 10% v/v of H{sub 2}O{sub 2} concentrated solution at 30% v/v, 10% w/w pulp density, 70 °C and 3 h of reaction. Two series of precipitation tests for zinc are carried out: a 2{sup 2} full factorial design and a completely randomized factorial design. In these series the factors investigated are pH of solution during the precipitation and the amount of sodium sulphide added to precipitate zinc sulphide. The data of these tests are used to describe two empirical mathematical models for zinc and yttrium precipitation yields by regression analysis. The highest precipitation yields for zinc are obtained under the following conditions: pH equal to 2–2.5% and 10–12% v/v of Na{sub 2}S concentrated solution at 10% w/v. In these conditions the coprecipitation of yttrium is of 15–20%. Finally further yttrium precipitation experiments by oxalic acid on the residual solutions, after removing of zinc, show that yttrium could be recovered and calcined to obtain the final product as yttrium oxide. The achieved results allow to propose a CRT recycling process based on leaching of fluorescent powder from cathode ray tube and recovery of yttrium oxide after removing of zinc by precipitation. The final recovery of yttrium is 75–80%.

  16. Compact Fluorescent Lighting in America: Lessons Learned on the Way to Market

    SciTech Connect (OSTI)

    Sandahl, Linda J.; Gilbride, Theresa L.; Ledbetter, Marc R.; Steward, Heidi E.; Calwell, Chris

    2006-05-22T23:59:59.000Z

    This report describes the history of compact fluorescent lamps (CFLs) in America. CFLs were introduced in the 1970s; however, it has taken more than 20 years for them to gain widespread recognition in the U.S. residential lighting market. This report reviews the development of CFLs, efforts to increase market acceptance of them, and barriers to that acceptance. Lessons to be learned from this study of CFLs are identified in hopes of assisting future market introduction efforts for other promising energy-efficient technologies. This report was prepared by the Pacific Northwest National Laboratory for the U.S. Department of Energy’s Office of Building Technologies, Emerging Technologies Program.

  17. Fluorescence method for enzyme analysis which couples aromatic amines with aromatic aldehydes

    DOE Patents [OSTI]

    Smith, R.E.; Dolbeare, F.A.

    1980-10-21T23:59:59.000Z

    Analysis of proteinases is accomplished using conventional amino acid containing aromatic amine substrates. Aromatic amines such as 4-methoxy-2-naphthylamine (4M2NA), 2-naphthylamine, aminoisophthalic acid dimethyl ester, p-nitroaniline, 4-methoxy-1-aminofluorene and coumarin derivatives resulting from enzymatic hydrolysis of the substrate couples with aromatic aldehydes such as 5-nitrosalicylaldehyde (5-NSA), benzaldehyde and p-nitrobenzaldehyde to produce Schiff-base complexes which are water insoluble. Certain Schiff-base complexes produce a shift from blue to orange-red (visible) fluorescence. Such complexes are useful in the assay of enzymes. No Drawings

  18. Fluorescence method for enzyme analysis which couples aromatic amines with aromatic aldehydes

    DOE Patents [OSTI]

    Smith, Robert E. [557 Escondido Cir., Livermore, CA 94550; Dolbeare, Frank A. [5178 Diane La., Livermore, CA 94550

    1980-10-21T23:59:59.000Z

    Analysis of proteinases is accomplished using conventional amino acid containing aromatic amine substrates. Aromatic amines such as 4-methoxy-2-naphthylamine (4M2NA), 2-naphthylamine, aminoisophthalic acid dimethyl ester, p-nitroaniline, 4-methoxy-1-aminofluorene and coumarin derivatives resulting from enzymatic hydrolysis of the substrate couples with aromatic aldehydes such as 5-nitrosalicylaldehyde (5-NSA), benzaldehyde and p-nitrobenzaldehyde to produce Schiff-base complexes which are water insoluble. Certain Schiff-base complexes produce a shift from blue to orange-red (visible) fluorescence. Such complexes are useful in the assay of enzymes.

  19. Signatures of hot electrons and fluorescence in Mo K? emission on Z

    SciTech Connect (OSTI)

    Hansen, S. B.; Ampleford, D. J.; Cuneo, M. E.; Jones, B.; Jennings, C. A.; Coverdale, C. A.; Rochau, G. A.; Dunham, G. [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)] [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States); Ouart, N.; Dasgupta, A.; Giuliani, J. L. [Naval Research Laboratory, Washington, DC 20375 (United States)] [Naval Research Laboratory, Washington, DC 20375 (United States); Apruzese, J. P. [Consultant to NRL through Engility Corp., Chantilly, Virginia 20151 (United States)] [Consultant to NRL through Engility Corp., Chantilly, Virginia 20151 (United States)

    2014-03-15T23:59:59.000Z

    Recent experiments on the Z accelerator have produced high-energy (17?keV) inner-shell K-alpha emission from molybdenum wire array z-pinches. Extensive absolute power and spectroscopic diagnostics along with collisional-radiative modeling enable detailed investigation into the roles of thermal, hot electron, and fluorescence processes in the production of high-energy x-rays. We show that changing the dimensions of the arrays can impact the proportion of thermal and non-thermal K-shell x-rays.

  20. Investigation and technique in the fluorescent spectra examination of crude oil

    E-Print Network [OSTI]

    Chambers, Gilbert Vester

    1958-01-01T23:59:59.000Z

    by chromato- graphy and distillation. The adsorbent was Alcoa activated alumina, chromatographic grade F-20. Support for the adsorbent was Pyrex brand glass fibre and cleaned B 0, A. sea sand. 11 DEVELOPl';, 'EI&T OF TEOHN IQUE Fluorescent intensity... the eluating power of the developer. Alumina was used as the adsorbent. It was pre- treated with nitric acid, washed with water, then alcohol and finally activated by heating two hours at 165 C under vacuum ($0). The adsorbent was slurried into the column...

  1. The performance of the corrector lenses for the Auger fluorescence detector

    SciTech Connect (OSTI)

    Sato, Ricardo; Escobar, Carlos O.; /Campinas State U.

    2005-07-01T23:59:59.000Z

    We present an analysis of the effect that the corrector lenses (Schmidt Optics) have on the overall performance of the Auger Fluorescence Detector. The analysis uses real data from the telescopes. Figures of merit for the corrector lenses performance include shower trigger rate and the distribution of the distance of closest approach to the shower axis. As a result of this analysis we may say that the effective light collection area of a telescope nearly doubles with the use of a corrector lens at its aperture.

  2. A dosimetry study for a K-fluorescent x-ray system

    E-Print Network [OSTI]

    Beard, Travis Newton

    1975-01-01T23:59:59.000Z

    spectra from a Si(Li) semi-conductor radiation detector. The spectrum for the copper target indicated a considerable amount of scattered radiation from thc target, as compared to that produced by the other targets. Lip thcrmoluminesccnt dosimeters (TLD... of ionizing radiation detectors. The photon response of many detectors varies with the incident photon energy, especially in the 10-100 keV energy region. The proper choice of K-fluorescent X-ray radiators enables one to make very accurate energy...

  3. Metal enhanced fluorescence in rare earth doped plasmonic core-shell nanoparticles

    E-Print Network [OSTI]

    Derom, S; Pillonnet, A; Benamara, O; Jurdyc, A M; Girard, C; Francs, G Colas des

    2013-01-01T23:59:59.000Z

    We theoretically and numerically investigate metal enhanced fluorescence of plasmonic core-shell nanoparticles doped with rare earth (RE) ions. Particle shape and size are engineered to maximize the average enhancement factor (AEF) of the overall doped shell. We show that the highest enhancement (11 in the visible and 7 in the near-infrared) are achieved by tuning either the dipolar or quadrupolar particle resonance to the rare earth ions excitation wavelength. Additionally, the calculated AEFs are compared to experimental data reported in the literature, obtained in similar conditions (plasmon mediated enhancement) or when a metal-RE energy transfer mechanism is involved.

  4. Methods and kits for nucleic acid analysis using fluorescence resonance energy transfer

    DOE Patents [OSTI]

    Kwok, Pui-Yan (Clayton, MO); Chen, Xiangning (St. Louis, MO)

    1999-01-01T23:59:59.000Z

    A method for detecting the presence of a target nucleotide or sequence of nucleotides in a nucleic acid is disclosed. The method is comprised of forming an oligonucleotide labeled with two fluorophores on the nucleic acid target site. The doubly labeled oligonucleotide is formed by addition of a singly labeled dideoxynucleoside triphosphate to a singly labeled polynucleotide or by ligation of two singly labeled polynucleotides. Detection of fluorescence resonance energy transfer upon denaturation indicates the presence of the target. Kits are also provided. The method is particularly applicable to genotyping.

  5. Conformation and dynamics of nucleotides in bulges and symmetric internal loops in duplex DNA studied by EPR and fluorescence spectroscopies

    SciTech Connect (OSTI)

    Cekan, Pavol [University of Iceland, Science Institute, Dunhaga 3, 107 Reykjavik (Iceland)] [University of Iceland, Science Institute, Dunhaga 3, 107 Reykjavik (Iceland); Sigurdsson, Snorri Th., E-mail: snorrisi@hi.is [University of Iceland, Science Institute, Dunhaga 3, 107 Reykjavik (Iceland)

    2012-04-13T23:59:59.000Z

    Highlights: Black-Right-Pointing-Pointer Bulges and loops were studied by both EPR and fluorescence spectroscopies using the probe C/C{sup f}. Black-Right-Pointing-Pointer One-base bulge was in a temperature-dependent equilibrium between looped-out and stacked states. Black-Right-Pointing-Pointer Bases in two- and three-base bulges were stacked at all temperatures, resulting in DNA bending. Black-Right-Pointing-Pointer Bases were stacked in symmetrical two- to five-base internal loops, according to EPR data. Black-Right-Pointing-Pointer Unexpectedly high fluorescence for the smaller loops indicated local structural perturbations. -- Abstract: The dynamics and conformation of base bulges and internal loops in duplex DNA were studied using the bifunctional spectroscopic probe C, which becomes fluorescent (C{sup f}) upon reduction of the nitroxide functional group, along with EPR and fluorescence spectroscopies. A one-base bulge was in a conformational equilibrium between looped-out and stacked states, the former favored at higher temperature and the latter at lower temperature. Stacking of bulge bases was favored in two- and three-base bulges, independent of temperature, resulting in DNA bending as evidenced by increased fluorescence of C{sup f}. EPR spectra of C-labeled three-, four- and five-base symmetrical interior DNA bulges at 20 Degree-Sign C showed low mobility, indicating that the spin-label was stacked within the loop. The spin-label mobility at 37 Degree-Sign C increased as the loops became larger. A considerable variation in fluorescence between different loops was observed, as well as a temperature-dependence within constructs. Fluorescence unexpectedly increased as the size of the loop decreased at 2 Degree-Sign C. Fluorescence of the smallest loops, where a single T{center_dot}T mismatch was located between the stem region and the probe, was even larger than for the single strand, indicating a considerable local structural deformation of these loops from regular B-DNA. These results show the value of combining EPR and fluorescence spectroscopy to study non-helical regions of nucleic acids.

  6. Phosphors for near UV-Emitting LED's for Efficacious Generation of White Light

    SciTech Connect (OSTI)

    McKittrick, Joanna

    2013-09-30T23:59:59.000Z

    1) We studied phosphors for near-UV (nUV) LED application as an alternative to blue LEDs currently being used in SSL systems. We have shown that nUV light sources could be very efficient at high current and will have significantly less binning at both the chip and phosphor levels. We identified phosphor blends that could yield 4100K lamps with a CRI of approximately 80 and LPWnUV,opt equal to 179 for the best performing phosphor blend. Considering the fact that the lamps were not optimized for light coupling, the results are quite impressive. The main bottleneck is an optimum blue phosphor with a peak near 440 nm with a full width half maximum of about 25 nm and a quantum efficiency of >95%. Unfortunately, that may be a very difficult task when we want to excite a phosphor at ~400 nm with a very small margin for Stokes shift. Another way is to have all the phosphors in the blend having the excitation peak at 400 nm or slightly shorter wavelength. This could lead to a white light source with no body color and optimum efficacy due to no self-absorption effects by phosphors in the blend. This is even harder than finding an ideal blue phosphor, but not necessarily impossible. 2) With the phosphor blends identified, light sources using nUV LEDs at high current could be designed with comparable efficacy to those using blue LEDs. It will allow us to design light sources with multiple wattages using the same chips and phosphor blends simply by varying the input current. In the case of blue LEDs, this is not currently possible because varying the current will lower the efficacy at high current and alter the color point. With improvement of phosphor blends, control over CRI could improve. Less binning at the chip level and also at the phosphor blend level could reduce the cost of SSL light sources. 3) This study provided a deeper understanding of phosphor characteristics needed for LEDs in general and nUV LEDs in particular. Two students received Ph.D. degrees and three undergraduates participated in this work. Two of the undergraduate students are now in graduate school. The results were widely disseminated – 20 archival journal publications (published, accepted or in preparation) and three conference proceedings resulted. The students presented their work at 11 different national/international conferences (32 oral or poster presentations) and the PI’s delivered 12 invited, keynote or plenary lectures.

  7. Standard test method for determination of uranium or gadolinium (or both) in gadolinium oxide-uranium oxide pellets or by X-ray fluorescence (XRF)

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    2008-01-01T23:59:59.000Z

    Standard test method for determination of uranium or gadolinium (or both) in gadolinium oxide-uranium oxide pellets or by X-ray fluorescence (XRF)

  8. X-Ray Fluorescence (XRF) Analysis of Obsidian Artifacts from the Spur Cross Ranch Site, AZ U:1:12 (ASU)

    E-Print Network [OSTI]

    Shackley, M. Steven

    1986-01-01T23:59:59.000Z

    r. X-RAY FLUORESCENCE (XRF) ANALYSIS OF OBSIDIAN ARTIFACTS62:426-437. SOUTHWEST XRF PAPER C_' Table 1. INTEGRATED

  9. Method and apparatus for enhanced evanescent fluorescence and color filtering using a high refractive index thin film coating

    DOE Patents [OSTI]

    Kao, Hung Pin (2124 Promontory Cir., San Ramon, CA 94583); Schoeniger, Joseph (126 Echo Ave., Oakland, CA 94611); Yang, Nancy (72 Bacon Ct., Lafayette, CA 94549)

    2001-01-01T23:59:59.000Z

    A technique for increasing the excitation and collection of evanescent fluorescence radiation emanating from a fiber optic sensor having a high refractive index (n.sub.r), dielectric thin film coating has been disclosed and described. The invention comprises a clad optical fiber core whose cladding is removed on a distal end, the distal end coated with a thin, non-porous, titanium dioxide sol-gel coating. It has been shown that such a fiber will exhibit increased fluorescence coupling due in part by 1) increasing the intensity of the evanescent field at the fiber core surface by a constructive interference effect on the propagating light, and 2) increasing the depth of penetration of the field in the sample. The interference effect created by the thin film imposes a wavelength dependence on the collection of the fluorescence and also suggests a novel application of thin films for color filtering as well as increasing collected fluorescence in fiber sensors. Collected fluorescence radiation increased by up to 6-fold over that of a bare fused silica fiber having a numerical aperture (N.A.) of O.6.

  10. Superselective Particle Embolization Enhances Efficacy of Radiofrequency Ablation: Effects of Particle Size and Sequence of Action

    SciTech Connect (OSTI)

    Tanaka, Toshihiro, E-mail: toshihir@bf6.so-net.ne.jp [Nara Medical University, Department of Radiology (Japan); Isfort, Peter, E-mail: isfort@hia.rwth-aachen.de [RWTH Aachen University, Applied Medical Engineering, Helmholtz-Institute Aachen (Germany); Braunschweig, Till, E-mail: tbraunschweig@ukaachen.de; Westphal, Saskia, E-mail: swestphal@ukaachen.de [RWTH Aachen University, Department of Pathology, Aachen University Hospital (Germany); Woitok, Anna, E-mail: awoitok@ukaachen.de [RWTH Aachen University, Institute for Laboratory Animal Science (Germany); Penzkofer, Tobias, E-mail: penzkofer@rad.rwth-aachen.de; Bruners, Philipp, E-mail: bruners@rad.rwth-aachen.de [RWTH Aachen University, Applied Medical Engineering, Helmholtz-Institute Aachen (Germany); Kichikawa, Kimihiko, E-mail: kkichika@naramed-u.ac.jp [Nara Medical University, Department of Radiology (Japan); Schmitz-Rode, Thomas, E-mail: smiro@hia.rwth-aachen.de; Mahnken, Andreas H., E-mail: mahnken@rad.rwth-aachen.de [RWTH Aachen University, Applied Medical Engineering, Helmholtz-Institute Aachen (Germany)

    2013-06-15T23:59:59.000Z

    Purpose. To evaluate the effects of particle size and course of action of superselective bland transcatheter arterial embolization (TAE) on the efficacy of radiofrequency ablation (RFA). Methods. Twenty pigs were divided into five groups: group 1a, 40-{mu}m bland TAE before RFA; group 1b, 40-{mu}m bland TAE after RFA; group 2a, 250-{mu}m bland TAE before RFA; group 2b, 250-{mu}m bland TAE after RFA and group 3, RFA alone. A total of 40 treatments were performed with a combined CT and angiography system. The sizes of the treated zones were measured from contrast-enhanced CTs on days 1 and 28. Animals were humanely killed, and the treated zones were examined pathologically. Results. There were no complications during procedures and follow-up. The short-axis diameter of the ablation zone in group 1a (mean {+-} standard deviation, 3.19 {+-} 0.39 cm) was significantly larger than in group 1b (2.44 {+-} 0.52 cm; P = 0.021), group 2a (2.51 {+-} 0.32 cm; P = 0.048), group 2b (2.19 {+-} 0.44 cm; P = 0.02), and group 3 (1.91 {+-} 0.55 cm; P < 0.001). The greatest volume of ablation was achieved by performing embolization with 40-{mu}m particles before RFA (group 1a; 20.97 {+-} 9.65 cm{sup 3}). At histology, 40-{mu}m microspheres were observed to occlude smaller and more distal arteries than 250-{mu}m microspheres. Conclusion. Bland TAE is more effective before RFA than postablation embolization. The use of very small 40-{mu}m microspheres enhances the efficacy of RFA more than the use of larger particles.

  11. Radiation Segmentectomy: A Novel Approach to Increase Safety and Efficacy of Radioembolization

    SciTech Connect (OSTI)

    Riaz, Ahsun; Gates, Vanessa L.; Atassi, Bassel; Lewandowski, Robert J. [Department of Radiology, Northwestern University, Chicago, IL (United States); Mulcahy, Mary F. [Department of Medicine, Northwestern University, Chicago, IL (United States); Ryu, Robert K.; Sato, Kent T. [Department of Radiology, Northwestern University, Chicago, IL (United States); Baker, Talia [Department of Transplant Surgery, Northwestern University, Chicago, IL (United States); Kulik, Laura [Department of Medicine, Northwestern University, Chicago, IL (United States); Gupta, Ramona [Department of Radiology, Northwestern University, Chicago, IL (United States); Abecassis, Michael [Department of Transplant Surgery, Northwestern University, Chicago, IL (United States); Benson, Al B. [Department of Medicine, Northwestern University, Chicago, IL (United States); Omary, Reed [Department of Radiology, Northwestern University, Chicago, IL (United States); Millender, Laura [Department of Radiation Oncology, Northwestern University, Chicago, IL (United States); Kennedy, Andrew [Department of Radiation Oncology, Wake Radiology Oncology, Cary, NC (United States); Salem, Riad, E-mail: r-salem@northwestern.ed [Department of Radiology, Northwestern University, Chicago, IL (United States); Department of Transplant Surgery, Northwestern University, Chicago, IL (United States)

    2011-01-01T23:59:59.000Z

    Purpose: To describe a technique of segmental radioembolization for the treatment of patients with unresectable hepatocellular carcinoma (HCC). Radiation segmentectomy was defined as radioembolization of two or fewer hepatic segments. We sought to (1) calculate dose when activity is delivered segmentally assuming uniform and nonuniform distribution and, (2) determine safety and efficacy of this novel technique. Methods and Materials: A total of 84 patients with HCC who were treated with {sup 90}Y radioembolization using a segmental approach were included in this analysis. The dose delivered to the segment was calculated assuming uniform and nonuniform microsphere distribution within the treatment volume. To calculate dose assuming nonuniform distribution, a tumor hypervascularity ratio was assigned. Posttreatment response (using size and necrosis guidelines), toxicity, time to progression, and survival were determined. Results: The median treatment volume was 110 cm{sup 3}. The median radiation-naive liver volume was 1403 cm{sup 3}. The median dose delivered to the segment(s) assuming uniform distribution was 521 Gy. Taking into account tumor hypervascularity (nonuniform distribution), the median dose delivered to the tumor and normal infused hepatic volume was 1214 Gy and 210 Gy, respectively. Response by size and necrosis guidelines was seen in 59% and 81% of patients. Grade 3/4 biochemical toxicities were observed in 8 patients (9%). Median time to progression was 13.6 months (95% confidence interval, 9.3-18.7 months); median survival was 26.9 months (95% confidence interval, 20.5-30.2 months). Conclusions: Radiation segmentectomy is a safe and efficacious method of selectively delivering high dose to the tumor with minimal exposure of normal parenchyma.

  12. Isotopic imaging via nuclear resonance fluorescence with laser-based Thomson radiation

    DOE Patents [OSTI]

    Barty, Christopher P. J. (Hayward, CA); Hartemann, Frederic V. (San Ramon, CA); McNabb, Dennis P. (Alameda, CA); Pruet, Jason A. (Brentwood, CA)

    2009-07-21T23:59:59.000Z

    The present invention utilizes novel laser-based, high-brightness, high-spatial-resolution, pencil-beam sources of spectrally pure hard x-ray and gamma-ray radiation to induce resonant scattering in specific nuclei, i.e., nuclear resonance fluorescence. By monitoring such fluorescence as a function of beam position, it is possible to image in either two dimensions or three dimensions, the position and concentration of individual isotopes in a specific material configuration. Such methods of the present invention material identification, spatial resolution of material location and ability to locate and identify materials shielded by other materials, such as, for example, behind a lead wall. The foundation of the present invention is the generation of quasimonochromatic high-energy x-ray (100's of keV) and gamma-ray (greater than about 1 MeV) radiation via the collision of intense laser pulses from relativistic electrons. Such a process as utilized herein, i.e., Thomson scattering or inverse-Compton scattering, produces beams having diameters from about 1 micron to about 100 microns of high-energy photons with a bandwidth of .DELTA.E/E of approximately 10E.sup.-3.

  13. 3D optical sectioning with a new hyperspectral confocal fluorescence imaging system.

    SciTech Connect (OSTI)

    Nieman, Linda T.; Sinclair, Michael B.; Davidson, George S.; Van Benthem, Mark Hilary; Haaland, David Michael; Timlin, Jerilyn Ann; Sasaki, Darryl Yoshio; Bachand, George David; Jones, Howland D. T.

    2007-02-01T23:59:59.000Z

    A novel hyperspectral fluorescence microscope for high-resolution 3D optical sectioning of cells and other structures has been designed, constructed, and used to investigate a number of different problems. We have significantly extended new multivariate curve resolution (MCR) data analysis methods to deconvolve the hyperspectral image data and to rapidly extract quantitative 3D concentration distribution maps of all emitting species. The imaging system has many advantages over current confocal imaging systems including simultaneous monitoring of numerous highly overlapped fluorophores, immunity to autofluorescence or impurity fluorescence, enhanced sensitivity, and dramatically improved accuracy, reliability, and dynamic range. Efficient data compression in the spectral dimension has allowed personal computers to perform quantitative analysis of hyperspectral images of large size without loss of image quality. We have also developed and tested software to perform analysis of time resolved hyperspectral images using trilinear multivariate analysis methods. The new imaging system is an enabling technology for numerous applications including (1) 3D composition mapping analysis of multicomponent processes occurring during host-pathogen interactions, (2) monitoring microfluidic processes, (3) imaging of molecular motors and (4) understanding photosynthetic processes in wild type and mutant Synechocystis cyanobacteria.

  14. Laser induced fluorescence imaging of thermal damage in polymer matrix composites

    SciTech Connect (OSTI)

    Fisher, W.G.; Meyer, K.E.; Wachter, E.A. [Oak Ridge National Lab., TN (United States); Perl, D.R. [N.A.S. North Island, San Diego, CA (United States). Naval Aviation Depot; Kulowitch, P.J. [Naval Air Warfare Center, Patuxent River, MD (United States). Aircraft Div.

    1997-06-01T23:59:59.000Z

    A simple, fluorescence based imaging system has been developed that is capable of identifying regions of thermal damage in polymer matrix composites (PMCs). These materials are playing an increasingly important role in the production of high performance vehicles and aircraft, where their low weight and high mechanical strength, combined with advancements in manufacturing technology, ensure increased use for a variety of applications. Of particular concern in the aerospace industry is the tendency of some PMC materials to become irreversibly damaged when exposed to elevated temperatures. Traditional nondestructive testing (NDT) techniques are capable of detecting physical anomalies such as cracks and delaminations but cannot detect initial heat damage, which occurs on a molecular scale. Spectroscopic techniques such as laser induced fluorescence provide an attractive means for detecting this type of damage and are amenable to imaging large, irregularly shaped surfaces. In this report the authors describe instrumentation capable of rapidly detecting thermal damage in graphite epoxy components and suggest improvements which will enable this technology to make quantitative judgments concerning the mechanical strength properties of heat damaged specimens.

  15. Dual x-ray fluorescence spectrometer and method for fluid analysis

    DOE Patents [OSTI]

    Wilson, Bary W.; Shepard, Chester L.

    2005-02-22T23:59:59.000Z

    Disclosed are an X-ray fluorescence (SRF) spectrometer and method for on-site and in-line determination of contaminant elements in lubricating oils and in fuel oils on board a marine vessel. An XRF source block 13 contains two radionuclide sources 16, 17 (e.g. Cd 109 and Fe 55), each oriented 180 degrees from the other to excite separate targets. The Cd 109 source 16 excites sample lube oil flowing through a low molecular weight sample line 18. The Fe 55 source 17 excites fuel oil manually presented to the source beam inside a low molecular weight vial 26 or other container. Two separate detectors A and B are arranged to detect the fluorescent x-rays from the targets, photons from the analyte atoms in the lube oil for example, and sulfur identifying x-rays from bunker fuel oil for example. The system allows both automated in-line and manual on-site analysis using one set of signal processing and multi-channel analyzer electronics 34, 37 as well as one computer 39 and user interface 43.

  16. Fluorescent growth bands in irradiated-bitumen nodules: Evidence of episodic hydrocarbon migration

    SciTech Connect (OSTI)

    Rasmussen, B. [Univ. of Western Australia, Nedlands (Australia)

    1997-01-01T23:59:59.000Z

    Minute rims of solid bitumen ({approximately}40-50 {mu}m thick) surround detrital radioactive grains in the Permian-Triassic sandstones and Arranoo Member of the Kockatea Shale from the northern Perth basin, Australia. The bitumen formed as Th- and U-bearing minerals (monazite, xenotime, zircon, thorite) irradiated and immobilized fluid hydrocarbons coming within range of alpha-particle emissions. using transmitted light and scanning electron microscopy and rims appear compositionally homogeneous, but under blue/violet epifluorescent illumination the bitumen displays complex concentric and contorted banding. These fluorescent textures indicate that multiple influxes of hydrocarbons passed through the reservoir sandstones. Following radiation-induced immobilization of hydrocarbons from the first oil influx, the bitumen nodules grew through a process of swelling and expansion outward form the mineral core during subsequent oil influxes, producing graded fluorescent growth bands. Oil droplets and lamellae also were adsorbed onto the outer portion of the nodules. Such bitumen nodules are a new and potentially important source of data for understanding the movement of hydrocarbons in sedimentary basins, specifically for identifying hydrocarbon pathways, the number of discrete hydrocarbon pulses, and the relative timing of oil migration.

  17. High Repetition Rate, LINAC-based Nuclear Resonance Fluorescence FY 2009 Final Report

    SciTech Connect (OSTI)

    Mathew Kinlaw; Scott Watson; James Johnson; Alan Hunt; Heather Seipel; Edward Reedy

    2009-10-01T23:59:59.000Z

    Nuclear Resonance Fluorescence (NRF), which is possible for nuclei with atomic numbers greater than helium (Z=2), occurs when a nuclear level is excited by resonant absorption of a photon and subsequently decays by reemission of a photon. The excited nuclear states can become readily populated, provided the incident photon’s energy is within the Doppler-broadened width of the energy level being excited. Utilizing continuous energy photon spectra, as is characteristic of a bremsstrahlung photon beam, as the inspection source, ensures that at least some fraction of the impinging beam will contribute to the population of the excited energy levels in the material of interest. Upon de-excitation, either to the ground state or to a lower-energy excited state, the emitted fluorescence photon’s energy will correspond to the energy difference between the excited state and the state to which it decays. As each isotope inherently contains unique nuclear energy levels, the NRF states for each isotope are also unique. By exploiting this phenomenon, NRF photon detection provides a well-defined signature for identifying the presence of individual nuclear species. This report summarizes the second year (Fiscal Year [FY] 2009) of a collaborative research effort between Idaho National Laboratory, Idaho State University’s Idaho Accelerator Center, and Pacific Northwest National Laboratory. This effort focused on continuing to assess and optimize NRF-based detection techniques utilizing a slightly modified, commercially available, pulsed medical electron accelerator.

  18. Status of the Silicon Photomultiplier Telescope FAMOUS for the Fluorescence Detection of UHECRs

    E-Print Network [OSTI]

    Niggemann, Tim; Brogueira, Pedro; Bueno, Antonio; Eichler, Hans Michael; Ferreira, Miguel; Hebbeker, Thomas; Lauscher, Markus; Mendes, Luís; Middendorf, Lukas; Navas, Sergio; Peters, Christine; Pimenta, Mário; Ruiz, Angel; Schumacher, Johannes; Stephan, Maurice

    2015-01-01T23:59:59.000Z

    An established technique for the measurement of ultra-high-energy-cosmic-rays is the detection of the fluorescence light induced in the atmosphere of the Earth, by means of telescopes equipped with photomultiplier tubes. Silicon photomultipliers (SiPMs) promise an increase in the photon detection efficiency which outperforms conventional photomultiplier tubes. In combination with their compact package, a moderate bias voltage of several ten volt and single photon resolution, the use of SiPMs can improve the energy and spatial resolution of air fluorescence measurements, and lead to a gain in information on the primary particle. Though, drawbacks like a high dark-noise-rate and a strong temperature dependency have to be managed. FAMOUS is a refracting telescope prototype instrumented with 64 SiPMs of which the main optical element is a Fresnel lens of 549.7 mm diameter and 502.1 mm focal length. The sensitive area of the SiPMs is increased by a special light collection system consisting of Winston cones. The t...

  19. A reaction-subdiffusion model of fluorescence recovery after photobleaching (FRAP)

    E-Print Network [OSTI]

    S. B. Yuste; E. Abad; K. Lindenberg

    2014-07-30T23:59:59.000Z

    Anomalous diffusion, in particular subdiffusion, is frequently invoked as a mechanism of motion in dense biological media, and may have a significant impact on the kinetics of binding/unbinding events at the cellular level. In this work we incorporate anomalous diffusion in a previously developed model for FRAP experiments. Our particular implementation of subdiffusive transport is based on a continuous time random walk (CTRW) description of the motion of fluorescent particles, as CTRWs lend themselves particularly well to the inclusion of binding/unbinding events. In order to model switching between bound and unbound states of fluorescent subdiffusive particles, we derive a fractional reaction-subdiffusion equation of rather general applicability. Using suitable initial and boundary conditions, this equation is then incorporated in the model describing two-dimensional kinetics of FRAP experiments. We find that this model can be used to obtain excellent fits to experimental data. Moreover, recovery curves corresponding to different radii of the circular bleach spot can be fitted by a single set of parameters. While not enough evidence has been collected to claim with certainty that CTRW is the underlying transport mechanism in FRAP experiments, the compatibility of our results with experimental data fuels the discussion as to whether normal diffusion or anomalous diffusion is the appropriate model, and as to whether anomalous diffusion effects are important to fully understand the outcomes of FRAP experiments. On a more technical side, we derive explicit analytic solutions of our model in certain limits.

  20. The efficacy of salmon carcass analogs for enhancing stream and fish production in the Wind River watershed

    E-Print Network [OSTI]

    The efficacy of salmon carcass analogs for enhancing stream and fish production in the Wind River watershed, Washington, to evaluate the effects of nutrient enhancement on measures of stream and fish production. We compared low level water chemistry, water quality, and periphyton, insect, and fish production

  1. To Aid or Not to Aid? Competing Narratives on the Efficacy of Foreign Aid in Sub-Saharan African

    E-Print Network [OSTI]

    Stuart, Kaleisha

    2011-08-08T23:59:59.000Z

    goals for which it is intended. This thesis is a cross-national analysis of Sub-Saharan Africa testing the efficacy of foreign aid flows on human welfare as measured by health outcomes. The amount of foreign aid is not significantly correlated...

  2. EVALUATION OF EFFICACY AND HUMAN HEALTH RISK OF AERIAL ULTRA-LOW VOLUME APPLICATIONS OF PYRETHRINS AND

    E-Print Network [OSTI]

    Peterson, Robert K. D.

    EVALUATION OF EFFICACY AND HUMAN HEALTH RISK OF AERIAL ULTRA-LOW VOLUME APPLICATIONS OF PYRETHRINS). A human health risk assessment conducted by Peterson et al. (2006) for truck-mounted ultra-low volume (ULV to epidemic levels and dispersed to all 58 counties in the state, and was associated with low

  3. Efficacy of open-ocean ballast water exchange as a means of preventing invertebrate invasions between freshwater ports

    E-Print Network [OSTI]

    globally. Mandatory ballast water exchange (BWE) was implemented for vessels carrying ballast water experiments to assess the efficacy of BWE on six operational transoceanic vessels traveling from the Great ports. BWE was verified by ship records and, in two cases, by in situ water quality sensors. BWE

  4. Near-infrared fluorescence glucose sensing based on glucose/galactose-binding protein coupled to 651-Blue Oxazine

    SciTech Connect (OSTI)

    Khan, Faaizah; Pickup, John C., E-mail: john.pickup@kcl.ac.uk

    2013-08-30T23:59:59.000Z

    Highlights: •We showed that the NIR fluorophore, 651-Blue Oxazine, is solvatochromic (polarity sensitive). •Blue Oxazine was covalently attached to mutants of glucose/galactose-binding protein (GBP). •Fluorescence intensity of GBP-Blue Oxazine increased with addition of glucose. •Fluorescence from bead-immobilised GBP-Blue Oxazine was detectable through skin in vitro. •This shows proof-of-concept for non-invasive glucose sensing using GBP-Blue Oxazine. -- Abstract: Near-infrared (NIR) fluorescent dyes that are environmentally sensitive or solvatochromic are useful tools for protein labelling in in vivo biosensor applications such as glucose monitoring in diabetes since their spectral properties are mostly independent of tissue autofluorescence and light scattering, and they offer potential for non-invasive analyte sensing. We showed that the fluorophore 651-Blue Oxazine is polarity-sensitive, with a marked reduction in NIR fluorescence on increasing solvent polarity. Mutants of glucose/galactose-binding protein (GBP) used as the glucose receptor were site-specifically and covalently labelled with Blue Oxazine using click chemistry. Mutants H152C/A213R and H152C/A213R/L238S showed fluorescence increases of 15% and 21% on addition of saturating glucose concentrations and binding constants of 6 and 25 mM respectively. Fluorescence responses to glucose were preserved when GBP-Blue Oxazine was immobilised to agarose beads, and the beads were excited by NIR light through a mouse skin preparation studied in vitro. We conclude GBP-Blue Oxazine shows proof-of-concept as a non-invasive continuous glucose sensing system.

  5. Analysis of nuclear materials by energy dispersive x-ray fluorescence and spectral effects of alpha decay

    SciTech Connect (OSTI)

    Worley, Christopher G [Los Alamos National Laboratory

    2009-01-01T23:59:59.000Z

    Energy dispersive X-ray fluorescence (EDXRF) spectra collected from alpha emitters are complicated by artifacts inherent to the alpha decay process, particularly when using portable instruments. For example, {sup 239}Pu EDXRF spectra exhibit a prominent uranium L X-ray emission peak series due to sample alpha decay rather than source-induced X-ray fluorescence. A portable EDXRF instrument was used to collect spectra from plutonium, americium, and a Pu-contaminated steel sample. The plutonium sample was also analyzed by wavelength dispersive XRF to demonstrate spectral differences observed when using these very different instruments.

  6. Evaluation of a portable x-ray fluorescence survey meter for the quantitative determination of trace metals in welding fumes

    E-Print Network [OSTI]

    Fehrenbacher, Mary Catherine

    1984-01-01T23:59:59.000Z

    Spectrometry Sensitivity Excitation Sources 12 16 Spectrometers and Detectors SHIELDED METAL ARC WELDING Health Effects of Welding THE PORTABLE X ? RAY FLUORESCENCE SURVEY METER METHODOLOGY RESULTS DISCUSSION OF RESULTS CAELUS I QblS RECQvfvt... Appendix C Basic Principle of AAS VITA Page 65 66 67 68 76 84 V1 11 LIST OF FIGURES Page 1. Transitions giving x-radiation 2. Fluorescent yield 3. Interaction of x-rays with matter 4. Particle size effects on x-ray intensity. . . 15 5...

  7. Theory of fluorescence correlation spectroscopy at variable observation area for two-dimensional diffusion on a meshgrid

    E-Print Network [OSTI]

    Nicolas Destainville

    2007-11-29T23:59:59.000Z

    It has recently been proposed, with the help of numerical investigations, that fluorescence correlation spectroscopy at variable observation area can reveal the existence of a meshgrid of semi-permeable barriers hindering the two-dimensional diffusion of tagged particles, such as plasmic membrane constituents. We present a complete theory confirming and accounting for these findings. It enables a reliable, quantitative exploitation of experimental data from which the sub-wavelength mesh size can be extracted. Time scales at which fluorescence correlation spectroscopy must be performed experimentally are discussed in detail.

  8. Ultrafast Excited-State Dynamics in the Green Fluorescent Protein Variant S65T/ H148D. 2. Unusual Photophysical Properties

    E-Print Network [OSTI]

    Boxer, Steven G.

    Ultrafast Excited-State Dynamics in the Green Fluorescent Protein Variant S65T/ H148D. 2. Unusual, California 94305-5080, and Institute of Molecular Biology and Department of Physics, UniVersity of Oregon of this variant at pH 5.6 by ultrafast fluorescence upconversion spectroscopy. Following excitation at 400 nm

  9. PhotochemisfvondPhofobiology. 1971 . Vol. 14,pp. 667-682. PergamonPress. Printed in Great Britain FLUORESCENCE INDUCTION IN THE RED ALGA

    E-Print Network [OSTI]

    Govindjee

    FLUORESCENCE INDUCTION IN THE RED ALGA PORPHYRIDIUM CRUENTUM P. MOHANTY, G. PAPAGEORGIOU* and GOVINDJEE in the red alga Porphyridium cruentum. Both the fast and the slow fluorescence yield changes are affected algae both in the fast (sec) and in the slow (min) region (see Refs. [l-31). Characteristic points

  10. Assessing the Efficacy of the Aerobic Methanotrophic Biofilter in Methane Hydrate Environments

    SciTech Connect (OSTI)

    Valentine, David

    2012-09-30T23:59:59.000Z

    In October 2008 the University of California at Santa Barbara (UCSB) initiated investigations of water column methane oxidation in methane hydrate environments, through a project funded by the National Energy Technology Laboratory (NETL) entitled: assessing the efficacy of the aerobic methanotrophic biofilter in methane hydrate environments. This Final Report describes the scientific advances and discoveries made under this award as well as the importance of these discoveries in the broader context of the research area. Benthic microbial mats inhabit the sea floor in areas where reduced chemicals such as sulfide reach the more oxidizing water that overlies the sediment. We set out to investigate the role that methanotrophs play in such mats at locations where methane reaches the sea floor along with sulfide. Mats were sampled from several seep environments and multiple sets were grown in-situ at a hydrocarbon seep in the Santa Barbara Basin. Mats grown in-situ were returned to the laboratory and used to perform stable isotope probing experiments in which they were treated with 13C-enriched methane. The microbial community was analyzed, demonstrating that three or more microbial groups became enriched in methane?s carbon: methanotrophs that presumably utilize methane directly, methylotrophs that presumably consume methanol excreted by the methanotrophs, and sulfide oxidizers that presumably consume carbon dioxide released by the methanotrophs and methylotrophs. Methanotrophs reached high relative abundance in mats grown on methane, but other bacterial processes include sulfide oxidation appeared to dominate mats, indicating that methanotrophy is not a dominant process in sustaining these benthic mats, but rather a secondary function modulated by methane availability. Methane that escapes the sediment in the deep ocean typically dissolved into the overlying water where it is available to methanotrophic bacteria. We set out to better understand the efficacy of this process as a biofilter by studying the distribution of methane oxidation and disposition of methanotrophic populations in the Pacific Ocean. We investigated several environments including the basins offshore California, the continental margin off Central America, and the shallow waters around gas seeps. We succeeded in identifying the distributions of activity in these environments, identified potential physical and chemical controls on methanotrophic activity, we further revealed details about the methanotrophic communities active in these settings, and we developed new approaches to study methanotrophic communities. These findings should improve our capacity to predict the methanotrophic response in ocean waters, and further our ability to generate specific hypotheses as to the ecology and efficacy of pelagic methanotrophic communites. The discharge of methane and other hydrocarbons to Gulf of Mexico that followed the sinking of the Deepwater Horizon provided a unique opportunity to study the methanotorphic biofilter in the deep ocean environment. We set out to understand the consumption of methane and the bloom of methanotrophs resulting from this event, as a window into the regional scale release of gas hydrate under rapid warming scenarios. We found that other hydrocarbon gases, notably propane and ethane, were preferred for consumption over methane, but that methane consumption accelerated rapidly and drove the depletion of methane within a matter of months after initial release. These results revealed the identity of the responsible community, and point to the importance of the seed population in determining the rate at which a methanotrophic community is able to respond to an input of methane. Collectively, these results provide a significant advance in our understanding of the marine methanotrohic biofilter, and further provide direction and context for future investigations of this important phenomenon. This project has resulted in fourteen publications to date, with five more circulating in draft form, and several others planned.

  11. Unusual expression of red fluorescence at M phase induced by anti-microtubule agents in HeLa cells expressing the fluorescent ubiquitination-based cell cycle indicator (Fucci)

    SciTech Connect (OSTI)

    Honda-Uezono, Asumi [Section of Oral Radiation Oncology, Department of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549 (Japan) [Section of Oral Radiation Oncology, Department of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549 (Japan); Section of Maxillofacial Surgery, Department of Maxillofacial and Neck Reconstruction, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549 (Japan); Kaida, Atsushi [Section of Oral Radiation Oncology, Department of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549 (Japan)] [Section of Oral Radiation Oncology, Department of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549 (Japan); Michi, Yasuyuki; Harada, Kiyoshi [Section of Maxillofacial Surgery, Department of Maxillofacial and Neck Reconstruction, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549 (Japan)] [Section of Maxillofacial Surgery, Department of Maxillofacial and Neck Reconstruction, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549 (Japan); Hayashi, Yoshiki; Hayashi, Yoshio [Department of Medicinal Chemistry, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo 192-0392 (Japan)] [Department of Medicinal Chemistry, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo 192-0392 (Japan); Miura, Masahiko, E-mail: masa.mdth@tmd.ac.jp [Section of Oral Radiation Oncology, Department of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549 (Japan)] [Section of Oral Radiation Oncology, Department of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549 (Japan)

    2012-11-16T23:59:59.000Z

    Highlights: Black-Right-Pointing-Pointer Fucci visualizes cell cycle by green and red fluorescence. Black-Right-Pointing-Pointer Plinabulin, induced unusual red fluorescence at M-phase in HeLa-Fucci cells. Black-Right-Pointing-Pointer The unusual pattern was followed by mitotic catastrophe. Black-Right-Pointing-Pointer The unusual pattern may be an early indicator of cell death in HeLa cells. -- Abstract: Plinabulin (NPI-2358) is a novel microtubule-depolymerizing agent. In HeLa cells, plinabulin arrests the cell-cycle at M phase and subsequently induces mitotic catastrophe. To better understand the effects on this compound on the cell-cycle, we used the fluorescent ubiquitination-based cell cycle indicator (Fucci), which normally enables G1 and S/G2/M cells to emit red and green fluorescence, respectively. When HeLa-Fucci cells were treated with 50 nM plinabulin, cells began to fluoresce both green and red in an unusual pattern; most cells exhibited the new pattern after 24 h of treatment. X-irradiation efficiently induced G2 arrest in plinabulin-treated cells and significantly retarded the emergence of the unusual pattern, suggesting that entering M phase is essential for induction of the pattern. By simultaneously visualizing chromosomes with GFP-histone H2B, we established that the pattern emerges after nuclear envelope breakdown but before metaphase. Pedigree assay revealed a significant relationship between the unusual expression and mitotic catastrophe. Nocodazole, KPU-133 (a more potent derivative of plinabulin), and paclitaxel also exerted similar effects. From these data, we conclude that the unusual pattern may be associated with dysregulation of late M phase-specific E3 ligase activity and mitotic catastrophe following treatment with anti-microtubule agents.

  12. Laser-induced fluorescence measurements on plasma science experiments at PPPL

    SciTech Connect (OSTI)

    Koepke, Mark

    2011-12-20T23:59:59.000Z

    Collaborative research between WVU and PPPL was carried out at WVU for the purpose of incorporating the sophisticated diagnostic technique known as laser-induced fluorescence (LIF) in the Paul-Trap Simulation Experiment (PTSX) at PPPL. WVU assembled a LIF system at WVU, transported it to PPPL, helped make LIF experiments on the PTSX device, participated in PTSX science, and trained PPPL staff in LIF techniques. In summary, WVU refurbished a non-operational LIF system being loaned from University of Maryland to PPPL and, by doing so, provided PPPL with additional diagnostic capability for its PTSX device and other General Plasma Science experiments. WVU students, staff, and faculty will visit PPPL to collaborate on PTSX experiments in the future.

  13. Reverse engineering the ancient ceramic technology based on X-ray fluorescence spectromicroscopy

    SciTech Connect (OSTI)

    Sciau, Philippe; Leon, Yoanna; Goudeau, Philippe; Fakra, Sirine C.; Webb, Sam; Mehta, Apurva

    2011-07-06T23:59:59.000Z

    We present results of X-ray fluorescence (XRF) microprobe analyses of ancient ceramic cross-sections aiming at deciphering the different firing protocols used for their production. Micro-focused XRF elemental mapping, Fe chemical mapping and Fe K-edge X-ray absorption near edge structure spectroscopy were performed on pre-sigillata ceramics from southern Gaul, and terra Sigillata vessels from Italy and southern Gaul. Pieces from the different workshops and regions showed significant difference in the starting clay material, clay conditioning and kiln firing condition. By contrast, sherds from the same workshop exhibited more subtle differences and possible misfirings. Understanding the precise firing conditions and protocols would allow recreation of kilns for various productions. Furthermore, evolution and modification of kiln design would shed some light on how ancient potters devised solutions to diverse technological problems they encountered.

  14. Coal liquefaction process streams characterization and evaluation. Novel analytical techniques for coal liquefaction: Fluorescence microscopy

    SciTech Connect (OSTI)

    Rathbone, R.F.; Hower, J.C.; Derbyshire, F.J. [Kentucky Univ., Lexington, KY (United States). Center for Applied Energy Research

    1991-10-01T23:59:59.000Z

    This study demonstrated the feasibility of using fluorescence and reflectance microscopy techniques for the examination of distillation resid materials derived from direct coal liquefaction. Resid, as defined here, is the 850{degrees}F{sup +} portion of the process stream, and includes soluble organics, insoluble organics and ash. The technique can be used to determine the degree of hydrogenation and the presence of multiple phases occurring within a resid sample. It can also be used to infer resid reactivity. The technique is rapid, requiring less than one hour for sample preparation and examination, and thus has apparent usefulness for process monitoring. Additionally, the technique can distinguish differences in samples produced under various process conditions. It can, therefore, be considered a potentially useful technique for the process developer. Further development and application of this analytical method as a process development tool is justified based on these results.

  15. Raman Spectroscopy of Lithium Hydride Corrosion: Selection of an Appropriate Excitation Wavelength to Minimize Fluorescence

    SciTech Connect (OSTI)

    Stowe, A. C.; Smyrl, N. R.

    2011-05-26T23:59:59.000Z

    The recent interest in a hydrogen-based fuel economy has renewed research into metal hydride chemistry. Many of these compounds react readily with water to release hydrogen gas and form a caustic. Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFT) has been used to study the hydrolysis reaction. The LiOH stretch appears at 3670 cm{sup -1}. Raman spectroscopy is a complementary technique that employs monochromatic excitation (laser) allowing access to the low energy region of the vibrational spectrum (<600 cm{sup -1}). Weak scattering and fluorescence typically prevent Raman from being used for many compounds. The role of Li{sub 2}O in the moisture reaction has not been fully studied for LiH. Li{sub 2}O can be observed by Raman while being hidden in the Infrared spectrum.

  16. 100-OL-1 Operable Unit Field Portable X-Ray Fluorescence (XRF) Analyzer Pilot Study Plans

    SciTech Connect (OSTI)

    Bunn, Amoret L.; Fritz, Brad G.; Wellman, Dawn M.

    2014-07-15T23:59:59.000Z

    A pilot study is being conducted to support the approval of the Remedial Investigation/Feasibility Study (RI/FS) Work Plan to evaluate the 100-OL-1 Operable Unit (OU) pre-Hanford orchard lands. Based on comments received by the U.S. Environmental Protection Agency (EPA) and Washington State Department of Ecology, the pilot study will evaluate the use of field portable X-ray fluorescence (XRF) spectrometry measurements for evaluating lead and arsenic concentrations on the soil surface as an indicator of past use of lead arsenate pesticide residue in the OU. The work will be performed in the field during the summer of 2014, and assist in the planning for the characterization activities in the RI/FS.

  17. Fluorescent of C-dot composite thin films and its properties

    SciTech Connect (OSTI)

    Mahen, Ea Cahya Septia, E-mail: ferry@fi.itb.ac.id; Nuryadin, Bebeh W., E-mail: ferry@fi.itb.ac.id; Iskandar, Ferry, E-mail: ferry@fi.itb.ac.id; Abdullah, Mikrajuddin, E-mail: ferry@fi.itb.ac.id; Khairurrijal, E-mail: ferry@fi.itb.ac.id [Department of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha 10 Bandung, 40132 (Indonesia)

    2014-02-24T23:59:59.000Z

    In the present work, we report the preparation of a fluorescent carbon nanodots (C-dots) epoxy composite thin films on a glass substrate. C-dots were prepared directly by a simple hydrothermal method using citric acid as a carbon source. The C-dots solutions were mixed with a transparent epoxy resin to form C-dot epoxy composite. Furthermore, the composite precursor was deposited on the glass substrate using a spin coating method in order to fabricate C-dot epoxy composite thin film. The transmittance intensity of C-dot composite film reached up to 90% in the visible light spectra. Using Swanopoel method, the film thickness of fabricated C-dot composite film was determined at about 1.45 ?m, a value lies in a typical range needed for a wide range application. Thus, the C-dot composite film is promising in broadening applications in various fields such as energy conversion, optoelectronics, and display technology.

  18. Identification Of Natural Dyes On Archaeological Textile Objects Using Laser Induced Fluorescent Technique

    SciTech Connect (OSTI)

    Abdel-Kareem, O. [Conservation Department, Faculty of Archaeology, Cairo University (Egypt); Eltokhy, A.; Harith, M. A. [National Institute of Laser Enhanced Science, Cairo University (Egypt)

    2011-09-22T23:59:59.000Z

    This study aims to evaluate the use of Laser Fluorescent as a non-destructive technique for identification of natural dyes on archaeological textile objects. In this study wool textile samples were dyed with 10 natural dyes such as cochineal, cutch, henna, indigo, Lac, madder, safflower, saffron, sumac and turmeric. These dyes common present on archaeological textile objects to be used as standard dyed textile samples. These selected natural dyes will be used as known references that can be used a guide to identify unknown archaeological dyes. The dyed textile samples were investigated with laser radiation in different wavelengths to detect the best wavelengths for identification each dye. This study confirms that Laser Florescent is very useful and a rapid technique can be used as a non-destructive technique for identification of natural dyes on archaeological textile objects. The results obtained with this study can be a guide for all conservators in identification of natural organic dyes on archaeological textile objects.

  19. NIST energy related inventions - electronic starter device for fluorescent lamps. Final report

    SciTech Connect (OSTI)

    NONE

    1998-06-01T23:59:59.000Z

    Due to silicon supplier failures to produce the 03/04 triac silicon as specified in the original proposal, the direction of the starter program was migrated to use available off the shelf power semiconductors. This had unexpected positive side effects including a reduction in component price, improved quality, and the refocus of engineering efforts to concentrate on the Super ASIC core technology. The starter program has begun shipments employing this new architecture, and is being well received both in the US and abroad. In its present form, the starter meets the original cost projections within 20%. Work is continuing on the 0.8 micron ASIC, which will allow for the starter to sell below $1.00 in volume. Even at the slightly higher price, interest is strong in replacing the low performance glow starter for small fluorescent applications with a high performance alternative.

  20. Integrated starting and running amalgam assembly for an electrodeless fluorescent lamp

    DOE Patents [OSTI]

    Borowiec, Joseph Christopher (Schenectady, NY); Cocoma, John Paul (Clifton Park, NY); Roberts, Victor David (Burnt Hills, NY)

    1998-01-01T23:59:59.000Z

    An integrated starting and running amalgam assembly for an electrodeless SEF fluorescent lamp includes a wire mesh amalgam support constructed to jointly optimize positions of a starting amalgam and a running amalgam in the lamp, thereby optimizing mercury vapor pressure in the lamp during both starting and steady-state operation in order to rapidly achieve and maintain high light output. The wire mesh amalgam support is constructed to support the starting amalgam toward one end thereof and the running amalgam toward the other end thereof, and the wire mesh is rolled for friction-fitting within the exhaust tube of the lamp. The positions of the starting and running amalgams on the wire mesh are jointly optimized such that high light output is achieved quickly and maintained, while avoiding any significant reduction in light output between starting and running operation.

  1. Detection of ultra-high energy cosmic ray showers with a single-pixel fluorescence telescope

    E-Print Network [OSTI]

    Fujii, T; Bertaina, M; Casolino, M; Dawson, B; Horvath, P; Hrabovsky, M; Jiang, J; Mandat, D; Matalon, A; Matthews, J N; Motloch, P; Palatka, M; Pech, M; Privitera, P; Schovanek, P; Takizawa, Y; Thomas, S B; Travnicek, P; Yamazaki, K

    2015-01-01T23:59:59.000Z

    We present a concept for large-area, low-cost detection of ultra-high energy cosmic rays (UHECRs) with a Fluorescence detector Array of Single-pixel Tele- scopes (FAST), addressing the requirements for the next generation of UHECR experiments. In the FAST design, a large field of view is covered by a few pixels at the focal plane of a mirror or Fresnel lens. We report first results of a FAST prototype installed at the Telescope Array site, consisting of a single 200 mm photomultiplier tube at the focal plane of a 1 m2 Fresnel lens system taken from the prototype of the JEM-EUSO experiment. The FAST prototype took data for 19 nights, demonstrating remarkable operational stability. We detected laser shots at distances of several kilometres as well as 16 highly significant UHECR shower candidates.

  2. High resolution laser induced fluorescence Doppler velocimetry utilizing saturated absorption spectroscopy

    SciTech Connect (OSTI)

    Aramaki, Mitsutoshi [Department of Electrical Engineering and Computer Science, Nagoya University, Nagoya 464-8603 (Japan); Ogiwara, Kohei; Etoh, Shuzo [Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, Kasuga 816-8580 (Japan); Yoshimura, Shinji [National Institute for Fusion Science, Toki 509-5292 (Japan); Tanaka, Masayoshi Y. [Department of Advanced Energy Engineering Science, Kyushu University, Kasuga 816-8580 (Japan)

    2009-05-15T23:59:59.000Z

    A high resolution laser induced fluorescence (LIF) system has been developed to measure the flow velocity field of neutral particles in an electron-cyclotron-resonance argon plasma. The flow velocity has been determined by the Doppler shift of the LIF spectrum, which is proportional to the velocity distribution function. Very high accuracy in velocity determination has been achieved by installing a saturated absorption spectroscopy unit into the LIF system, where the absolute value and scale of laser wavelength are determined by using the Lamb dip and the fringes of a Fabry-Perot interferometer. The minimum detectable flow velocity of a newly developed LIF system is {+-}2 m/s, and this performance remains unchanged in a long-time experiment. From the radial measurements of LIF spectra of argon metastable atoms, it is found that there exists an inward flow of neutral particles associated with neutral depletion.

  3. Temperature dependence of photoluminescence properties in a thermally activated delayed fluorescence emitter

    SciTech Connect (OSTI)

    Niwa, Akitsugu [Department of Physics and Electronics, Osaka Prefecture University, 1-1 Gakuencho, Nakaku, Sakai 599-8531 (Japan); Kobayashi, Takashi, E-mail: tkobaya@pe.osakafu-u.ac.jp; Nagase, Takashi; Naito, Hiroyoshi, E-mail: naito@pe.osakafu-u.ac.jp [Department of Physics and Electronics, Osaka Prefecture University, 1-1 Gakuencho, Nakaku, Sakai 599-8531 (Japan); The Research Institute for Molecular Electronic Devices, Osaka Prefecture University, Sakai 599-8531 (Japan); Goushi, Kenichi; Adachi, Chihaya [Center for Organic Photonics and Electronics Research, Kyushu University, 744 Motooka, Nishi, Fukuoka 819-0395 (Japan); International Institute for Carbon Neutral Energy Research (WPI-I2CNER), Kyushu University, 744 Motooka, Nishi, Fukuoka 819-0395 (Japan)

    2014-05-26T23:59:59.000Z

    Using steady-state and time-resolved photoluminescence (PL) spectroscopy, we have investigated the temperature dependence of PL properties of 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyano-benzene (4CzIPN), which have a small energy gap between its singlet and triplet excited states and thus exhibits efficient thermally activated delayed fluorescence [H. Uoyama et al., Nature 492, 235 (2012)]. Below around 100?K, PL quantum efficiency of 4CzIPN thin films is largely suppressed and strong photoexcitation intensity dependence appears. These features can be explained by using rate equations for the densities of singlet and triplet excited states considering a triplet-triplet annihilation process.

  4. Indirect determination of the electric field in plasma discharges using laser-induced fluorescence spectroscopy

    SciTech Connect (OSTI)

    Vaudolon, J., E-mail: julien.vaudolon@cnrs-orleans.fr; Mazouffre, S., E-mail: stephane.mazouffre@cnrs-orleans.fr [CNRS - ICARE (Institut de Combustion Aérothermique Réactivité et Environnement), 1 C Av. de la Recherche Scientifique, 45071 Orléans Cedex 2 (France)

    2014-09-15T23:59:59.000Z

    The evaluation of electric fields is of prime interest for the description of plasma characteristics. In this work, different methods for determining the electric field profile in low-pressure discharges using one- and two-dimensional Laser-Induced Fluorescence (LIF) measurements are presented and discussed. The energy conservation, fluid, and kinetic approaches appear to be well-suited for the electric field evaluation in this region of the plasma flow. However, the numerical complexity of a two-dimensional kinetic model is penalizing due to the limited signal-to-noise ratio that can be achieved, making the computation of the electric field subject to large error bars. The ionization contribution which appears in the fluid model makes it unattractive on an experimental viewpoint. The energy conservation and 1D1V kinetic approaches should therefore be preferred for the determination of the electric field when LIF data are used.

  5. Intramolecular excimer emission as a blue light source in fluorescent organic light emitting diodes: a promising molecular design

    E-Print Network [OSTI]

    Boyer, Edmond

    Intramolecular excimer emission as a blue light source in fluorescent organic light emitting diodes Light Emitting Diode (OLED), intermolecular p­p interactions should be usually suppressed to avoid any Emitting Diodes (SMOLEDs) is almost absent from the literature. In this work, three aryl-substituted Di

  6. Insight into the Common Mechanism of the Chromophore Formation in the Red Fluorescent Proteins: The Elusive Blue

    E-Print Network [OSTI]

    Krylov, Anna I.

    : The Elusive Blue Intermediate Revealed Ksenia B. Bravaya, Oksana M. Subach, Nadezhda Korovina, Vladislav V calculations identifying the nature of a blue intermediate, a key species in the process of the red chromophore formation in DsRed, TagRFP, fluorescent timers, and PAmCherry. The chromophore of the blue intermediate has

  7. Application of a ratiometric laser induced fluorescence (LIF) thermometry for micro-scale temperature measurement for natural convection flows

    E-Print Network [OSTI]

    Lee, Heon Ju

    2004-11-15T23:59:59.000Z

    cuvette, which was controlled by two thermo-bathes. 488nm Ar-ion laser used for incident light and two filter sets used for separating each fluorescence emission. Thermally stratified filed of 10mm channel with micro-scale resolution measured within 1...

  8. Development of a Cell-Based Fluorescence Resonance Energy Transfer Reporter for Bacillus anthracis Lethal Factor Protease

    SciTech Connect (OSTI)

    Kimura, R H; Steenblock, E R; Camarero, J A

    2007-03-22T23:59:59.000Z

    We report the construction of a cell-based fluorescent reporter for anthrax lethal factor (LF) protease activity using the principle of fluorescence resonance energy transfer (FRET). This was accomplished by engineering an Escherichia coli cell line to express a genetically encoded FRET reporter and LF protease. Both proteins were encoded in two different expression plasmids under the control of different tightly controlled inducible promoters. The FRET-based reporter was designed to contain a LF recognition sequence flanked by the FRET pair formed by CyPet and YPet fluorescent proteins. The length of the linker between both fluorescent proteins was optimized using a flexible peptide linker containing several Gly-Gly-Ser repeats. Our results indicate that this FRET-based LF reporter was readily expressed in E. coli cells showing high levels of FRET in vivo in the absence of LF. The FRET signal, however, decreased 5 times after inducing LF expression in the same cell. These results suggest that this cell-based LF FRET reporter may be used to screen genetically encoded libraries in vivo against LF.

  9. Proceedings of ICRC 2001: 769 c Copernicus Gesellschaft 2001 First measurements with the AUGER fluorescence detector data

    E-Print Network [OSTI]

    2000 the collaboration has started to in- stall an engineering array consisting of 40 tanks and 2 tele experimental results by measur- ing the energy spectrum, the arrival direction and the iso- Correspondence to distributed water tanks and the Fluorescence Detector (FD) with 30 tele- scopes which watch the night sky

  10. Double-strand DNA-templated formation of copper nanoparticles as fluorescent probe for label free nuclease enzyme detection

    E-Print Network [OSTI]

    Tan, Weihong

    cleavage activity. Thus, a label-free strategy for sensitive detection of nuclease has been developed B.V. All rights reserved. 1. Introduction As promising substitutes for organic dyes and quantum dots epithelial cervical cancer cells (HeLa cells) using fluorescent gold nanoparticles which emitted a stable

  11. Inferred influence of nutrient availability on the relationship between Sun-induced chlorophyll fluorescence and incident irradiance in the

    E-Print Network [OSTI]

    Kelley, Dan

    Inferred influence of nutrient availability on the relationship between Sun-induced chlorophyll July 2008. [1] This study examines variability in the relationship between Sun-induced chlorophyll, this is consistent with the established suggestion that Sun-induced fluorescence increases with nutrient stress

  12. DEVELOPMENT AND CALIBRATION OF A TWO-DYE FLUORESCENCE SYSTEM FOR USE IN TWO-PHASE MICRO FLOW THERMOMETRY

    E-Print Network [OSTI]

    Hidrovo, Carlos H.

    The increasing need for more effective cooling in electronic devices has led to research into the useDEVELOPMENT AND CALIBRATION OF A TWO-DYE FLUORESCENCE SYSTEM FOR USE IN TWO-PHASE MICRO FLOW and modeling of two- phase cooling strategies in micro-scale geometries. In order to verify these models

  13. Uranium and plutonium solution assays by transmission-corrected x-ray fluorescence

    SciTech Connect (OSTI)

    Ryon, R W; Ruhter, W D; Rudenko, V; Sirontinin, A; Petrov, A A

    1999-09-08T23:59:59.000Z

    We have refined and tested a previously developed x-ray fluorescence analysis technique for uranium and plutonium solutions that compensates for variations in the absorption of the exciting gamma rays and fluorescent x-rays. We use {sup 57}Co to efficiently excite the K lines of the elements, and a mixed {sup 57}Co plus {sup 153}Gd transmission source to correct for variations in absorption. The absorption correction is a unique feature of our technique. It is possible to accurately calibrate the system with a single solution standard. There does not need to be a close match in composition (i.e., absorption) between the standard(s) and solutions to be analyzed. Specially designed equipment incorporates a planar intrinsic germanium detector, excitation and transmission radioisotopes, and specimen holder. The apparatus can be inserted into a rubber glove of a glovebox, keeping the apparatus outside and the solutions inside the glovebox, thereby protecting the user and the equipment from possible contamination. An alternate design may be used in chemical reprocessing plants, providing continuous monitoring, by measuring the trans-actinides through stainless steel piping. This technique has been tested at the Bochvar Research Institute of Inorganic Materials in Moscow for possible use in the Russian complex of nuclear facilities. This is part of a cooperative program between laboratories in the United States and Russia to strengthen systems of nuclear materials protection, control, and accountability (MPC and A). A part of this program is to accurately measure and track inventories of materials, thus the need for good non-destructive analytical techniques such as the one described here.

  14. Solvatochromism and time-resolved fluorescence of the antitumor agent mitoxantrone and its analogues in solution and in DNA

    SciTech Connect (OSTI)

    Su Lin; Struve, W.S. (Ames Lab., IA (United States))

    1991-03-21T23:59:59.000Z

    The electronic spectroscopy and fluorescence kinetics of 1,4-dihydroxy-5,8-(2-(2-((2-hydroxyethyl)amino)ethyl)amino)-9,10-anthracenedione (mitoxantrone) and three closely related analogues have been studied in several solvents. The small solvatochromic blue shifts of their visible charge-transfer absorption bands in protic solvents are dominated by interactions with a solvent H-bonding donor, rather than by dipole-dielectric solute-solvent electrostatics. These interactions are unrelated to the phenolic hydroxy groups or the distal N atoms on the side chains but must be localized to the carbonyl groups. The fluorescence decays of all four anthraquinones are controlled by subnanosecond nonradiative relaxation in all solvents studied. At least two decay mechanisms contribute to the observed fluorescence kinetics in solution: (a) subnanosecond internal conversion that is accelerated relative to that in 1,4-diaminoanthraquinone by the presence of the flexible 1,4-side chains in mitoxantrone and its analogues; (b) an additional decay mode that is accentuated in H-bonding solvents. A substantial normal isotope effect occurs in the fluorescence lifetimes of mitoxantrone in perdeuterated water and methanol but not in aprotic solvents. When bound to double-stranded calf thymus DNA, mitoxantrone displays a fluorescence lifetime similar to that in aprotic solvents, suggesting that H-bonding interactions with water are precluded by chromophore intercalation. DNA-bound ametantrone exhibits a lifetime longer than that in either H-bonding or aprotic solvents, indicating that immobilization of the side chains through binding of the distal N atoms to the DNA backbone may influence the decay kinetics. This technique therefore shows potential for elucidating the DNA binding modes for a large class of intercalative drugs.

  15. Safety and Efficacy of the Gunther Tulip Retrievable Vena Cava Filter: Midterm Outcomes

    SciTech Connect (OSTI)

    Hoffer, Eric K., E-mail: eric.k.hoffer@hitchcock.org; Mueller, Rebecca J.; Luciano, Marcus R.; Lee, Nicole N.; Michaels, Anne T.; Gemery, John M. [Dartmouth-Hitchcock Medical Center, Department of Radiology, Section of Vascular and Interventional Radiology (United States)

    2013-08-01T23:59:59.000Z

    PurposeTo evaluate of the medium-term integrity, efficacy, and complication rate associated with the Gunther Tulip vena cava filter.MethodsA retrospective study was performed of 369 consecutive patients who had infrarenal Gunther Tulip inferior vena cava filters placed over a 5-year period. The mean patient age was 61.8 years, and 59 % were men. Venous thromboembolic disease and a contraindication to or complication of anticoagulation were the indications for filter placement in 86 % of patients; 14 % were placed for prophylaxis in patients with a mean of 2.3 risk factors. Follow-up was obtained by review of medical and radiologic records.ResultsMean clinical follow-up was 780 days. New or recurrent pulmonary embolus occurred in 12 patients (3.3 %). New or recurrent deep-vein thrombosis occurred in 53 patients (14.4 %). There were no symptomatic fractures, migrations, or caval perforations. Imaging follow-up in 287 patients (77.8 %) at a mean of 731 days revealed a single (0.3 %) asymptomatic fracture, migration greater than 2 cm in 36 patients (12.5 %), and no case of embolization. Of 122 patients with CT scans, asymptomatic perforations were identified in 53 patients (43.4 %) at a mean 757 days.ConclusionThe Gunther Tulip filter was safe and effective at 2-year follow-up. Complication rates were similar to those reported for permanent inferior vena cava filters.

  16. The use of starch matrices in slow release fungicide formulations and their efficacy in controlling Phymatotrichum omnivorum on cotton

    E-Print Network [OSTI]

    Small, Theresa Marie

    1984-01-01T23:59:59.000Z

    THE USE OF STARCH MATRICES IN SLO'hl RELEASE FUNGICIDE FORMULATIONS AND THEIR EFFICACY IN CONTROLLING PHYMATOTRICHUM OMNIVORUM ON COTTON A Thesis by THERESA MARIE SMALL Submitted to the Graduate College of Texas A&M University in partial... Thesis by THERESA MARIE SMALL Approved as to style and content by: Stuart . L a (Chairman of Committee) John M. Hal oin (Member) Morri s G. Merk le (Member) Rober . Pe it (Member) r ie owning (Head of Department August 1984 ABSTRACT...

  17. Encapsulated interferon-tau during Theiler's virus-induced demyelinating disease: efficacy of treatment and immune response profile

    E-Print Network [OSTI]

    Dean, Dana Deanna

    2009-05-15T23:59:59.000Z

    that begin to neutralize the IFN and cause the patient to become a ?biological non- responder?. The percentage of patients producing neutralizing antibodies in clinical trials (reviewed in Bertolotto et al., 2004) ranges from 2% (Avonex) to 50% (Betaferon... antibodies to IFNB during the first year of administration which can result in loss of treatment efficacy (Bertolotto et al., 2004). With oral administration in mice, no antibodies were detected against IFNT. IFNT treatment of EAE also resulted...

  18. Stress and self-efficacy of special education and general education student teachers during and after the student teaching internship

    E-Print Network [OSTI]

    Dickerson, Kimberly Lynn

    2009-05-15T23:59:59.000Z

    STRESS AND SELF-EFFICACY OF SPECIAL EDUCATION AND GENERAL EDUCATION STUDENT TEACHERS DURING AND AFTER THE STUDENT TEACHING INTERNSHIP A Dissertation by KIMBERLY LYNN DICKERSON Submitted to the Office of Graduate... EDUCATION STUDENT TEACHERS DURING AND AFTER THE STUDENT TEACHING INTERNSHIP A Dissertation by KIMBERLY LYNN DICKERSON Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree...

  19. SU-E-I-67: X-Ray Fluorescence for Energy Response Calibration of a Photon Counting Detector: A Simulation Study

    SciTech Connect (OSTI)

    Cho, H; Ding, H; Ziemer, B; Molloi, S [University of California, Irvine, CA (United States)

    2014-06-01T23:59:59.000Z

    Purpose: To investigate the feasibility of energy calibration and energy response characterization of a photon counting detector using x-ray fluorescence. Methods: A comprehensive Monte Carlo simulation study was done to investigate the influence of various geometric components on the x-ray fluorescence measurement. Different materials, sizes, and detection angles were simulated using Geant4 Application for Tomographic Emission (GATE) Monte Carlo package. Simulations were conducted using 100 kVp tungsten-anode spectra with 2 mm Al filter for a single pixel cadmium telluride (CdTe) detector with 3 × 3 mm2 in detection area. The fluorescence material was placed 300 mm away from both the x-ray source and the detector. For angular dependence measurement, the distance was decreased to 30 mm to reduce the simulation time. Compound materials, containing silver, barium, gadolinium, hafnium, and gold in cylindrical shape, were simulated. The object size varied from 5 to 100 mm in diameter. The angular dependence of fluorescence and scatter were simulated from 20° to 170° with an incremental step of 10° to optimize the fluorescence to scatter ratio. Furthermore, the angular dependence was also experimentally measured using a spectrometer (X-123CdTe, Amptek Inc., MA) to validate the simulation results. Results: The detection angle between 120° to 160° resulted in more optimal x-ray fluorescence to scatter ratio. At a detection angle of 120°, the object size did not have a significant effect on the fluorescence to scatter ratio. The experimental results of fluorescence angular dependence are in good agreement with the simulation results. The K? and K? peaks of five materials could be identified. Conclusion: The simulation results show that the x-ray fluorescence procedure has the potential to be used for detector energy calibration and detector response characteristics by using the optimal system geometry.

  20. Investigating the relationship between urban first and second grade classroom teachers' sense of efficacy for literacy instruction and the reading achievement of their highly mobile students 

    E-Print Network [OSTI]

    Valadez, Corinne Montalvo

    2006-10-30T23:59:59.000Z

    This correlation design study investigated the relationship between urban first and second grade classroom teachers� sense of efficacy for literacy instruction and the reading achievement of their highly mobile students. Teachers� sense...

  1. Efficacy of artesunate-amodiaquine for treating uncomplicated P. falciparum malaria in Sub-Saharan Africa: a multi-centre analysis

    E-Print Network [OSTI]

    2009-01-01T23:59:59.000Z

    A, Kamara K, Lam E, Checchi F, Balkan S, Scollo G, Durand R,Francis M, Noël F, Mulemba M, Balkan S: High efficacy of twoDenoncin A, van Herp M, Balkan S, Dujardin JC, D'Alessandro

  2. Nuclear Resonance Fluorescence to Measure Plutonium Mass in Spent Nuclear Fuel

    SciTech Connect (OSTI)

    Ludewigt, Bernhard A; Quiter, Brian J.; Ambers, Scott D.

    2011-01-14T23:59:59.000Z

    The Next Generation Safeguard Initiative (NGSI) of the U.S Department of Energy is supporting a multi-lab/university collaboration to quantify the plutonium (Pu) mass in spent nuclear fuel (SNF) assemblies and to detect the diversion of pins with non-destructive assay (NDA) methods. The following 14 NDA techniques are being studied: Delayed Neutrons, Differential Die-Away, Differential Die-Away Self-Interrogation, Lead Slowing Down Spectrometer, Neutron Multiplicity, Passive Neutron Albedo Reactivity, Total Neutron (Gross Neutron), X-Ray Fluorescence, {sup 252}Cf Interrogation with Prompt Neutron Detection, Delayed Gamma, Nuclear Resonance Fluorescence, Passive Prompt Gamma, Self-integration Neutron Resonance Densitometry, and Neutron Resonance Transmission Analysis. Understanding and maturity of the techniques vary greatly, ranging from decades old, well-understood methods to new approaches. Nuclear Resonance Fluorescence (NRF) is a technique that had not previously been studied for SNF assay or similar applications. Since NRF generates isotope-specific signals, the promise and appeal of the technique lies in its potential to directly measure the amount of a specific isotope in an SNF assay target. The objectives of this study were to design and model suitable NRF measurement methods, to quantify capabilities and corresponding instrumentation requirements, and to evaluate prospects and the potential of NRF for SNF assay. The main challenge of the technique is to achieve the sensitivity and precision, i.e., to accumulate sufficient counting statistics, required for quantifying the mass of Pu isotopes in SNF assemblies. Systematic errors, considered a lesser problem for a direct measurement and only briefly discussed in this report, need to be evaluated for specific instrument designs in the future. Also, since the technical capability of using NRF to measure Pu in SNF has not been established, this report does not directly address issues such as cost, size, development time, nor concerns related to the use of Pu in measurement systems. This report discusses basic NRF measurement concepts, i.e., backscatter and transmission methods, and photon source and {gamma}-ray detector options in Section 2. An analytical model for calculating NRF signal strengths is presented in Section 3 together with enhancements to the MCNPX code and descriptions of modeling techniques that were drawn upon in the following sections. Making extensive use of the model and MCNPX simulations, the capabilities of the backscatter and transmission methods based on bremsstrahlung or quasi-monoenergetic photon sources were analyzed as described in Sections 4 and 5. A recent transmission experiment is reported on in Appendix A. While this experiment was not directly part of this project, its results provide an important reference point for our analytical estimates and MCNPX simulations. Used fuel radioactivity calculations, the enhancements to the MCNPX code, and details of the MCNPX simulations are documented in the other appendices.

  3. Efficacy of Lower-Body Shielding in Computed Tomography Fluoroscopy-Guided Interventions

    SciTech Connect (OSTI)

    Mahnken, Andreas H., E-mail: mahnken@rad.rwth-aachen.de [RWTH Aachen, Department of Diagnostic and Interventional Radiology (Germany); Sedlmair, Martin [Siemens, Healthcare Sector (Germany); Ritter, Christine [University of Copenhagen, Niels Bohr Institute (Denmark); Banckwitz, Rosemarie; Flohr, Thomas [Siemens, Healthcare Sector (Germany)

    2012-12-15T23:59:59.000Z

    Purpose: Computed tomography (CT) fluoroscopy-guided interventions pose relevant radiation exposure to the interventionalist. The goal of this study was to analyze the efficacy of lower-body shielding as a simple structural method for decreasing radiation dose to the interventionalist without limiting access to the patient. Material and Methods: All examinations were performed with a 128-slice dual source CT scanner (12 Multiplication-Sign 1.2-mm collimation; 120 kV; and 20, 40, 60, and 80 mAs) and an Alderson-Rando phantom. Scatter radiation was measured with an ionization chamber and a digital dosimeter at standardized positions and heights with and without a lower-body lead shield (0.5-mm lead equivalent; Kenex, Harlow, UK). Dose decreases were computed for the different points of measurement. Results: On average, lower-body shielding decreased scatter radiation by 38.2% within a 150-cm radius around the shielding. This decrease is most significant close to the gantry opening and at low heights of 50 and 100 cm above the floor with a maximum decrease of scatter radiation of 95.9% close to the scanner's isocentre. With increasing distance to the gantry opening, the effect decreased. There is almost no dose decrease effect at {>=}150 above the floor. Scatter radiation and its decrease were linearly correlated with the tube current-time product (r{sup 2} = 0.99), whereas percent scatter radiation decrease was independent of the tube current-time product. Conclusion: Lower-body shielding is an effective way to decrease radiation exposure to the interventionalist and should routinely be used in CT fluoroscopy-guided interventions.

  4. Efficacy and Safety of Transarterial Radioembolization Versus Chemoembolization in Patients With Hepatocellular Carcinoma

    SciTech Connect (OSTI)

    Moreno-Luna, Laura E., E-mail: morenoluna.laura@gmail.com; Yang, Ju Dong; Sanchez, William [College of Medicine, Mayo Clinic, Division of Gastroenterology and Hepatology (United States); Paz-Fumagalli, Ricardo [College of Medicine, Mayo Clinic, Department of Radiology (United States); Harnois, Denise M.; Mettler, Teresa A. [College of Medicine, Mayo Clinic, Division of Gastroenterology and Hepatology (United States); Gansen, Denise N. [College of Medicine, Mayo Clinic, Department of Radiology (United States); Groen, Piet C. de; Lazaridis, Konstantinos N.; Narayanan Menon, K. V.; LaRusso, Nicholas F. [College of Medicine, Mayo Clinic, Division of Gastroenterology and Hepatology (United States); Alberts, Steven R. [College of Medicine, Mayo Clinic and Mayo Clinic Cancer Center, Department of Oncology (United States); Gores, Gregory J. [College of Medicine, Mayo Clinic, Division of Gastroenterology and Hepatology (United States); Fleming, Chad J. [College of Medicine, Mayo Clinic, Department of Radiology (United States); Slettedahl, Seth W.; Harmsen, William S.; Therneau, Terry M. [College of Medicine, Mayo Clinic, Department of Health Sciences Research (United States); Wiseman, Gregory A.; Andrews, James C. [College of Medicine, Mayo Clinic, Department of Radiology (United States); Roberts, Lewis R., E-mail: roberts.lewis@mayo.edu [College of Medicine, Mayo Clinic, Division of Gastroenterology and Hepatology (United States)

    2013-06-15T23:59:59.000Z

    Purpose. Intermediate-stage hepatocellular carcinoma (HCC) is usually treated with locoregional therapy using transarterial chemoembolization (TACE). Transarterial radioembolization (TARE) using {beta}-emitting yttrium-90 integral to the glass matrix of the microspheres is an alternative to TACE. This retrospective case-control study compared the outcomes and safety of TARE versus TACE in patients with unresectable HCC. Materials and Methods. Patients with unresectable HCC without portal vein thrombosis treated with TARE between 2005 and 2008 (n = 61) were retrospectively frequency-matched by age, sex, and liver dysfunction with TACE-treated patients (n = 55) in the Mayo Clinic Hepatobiliary Neoplasia Registry. Imaging studies were reviewed, and clinical and safety outcomes were abstracted from the medical records. Results. Complete tumor response was more common after TARE (12 %) than after TACE (4 %) (p = 0.17). When complete response was combined with partial response and stable disease, there was no difference between TARE and TACE. Median survival did not differ between the two groups (15.0 months for TARE and 14.4 months for TACE; p = 0.47). Two-year survival rates were 30 % for TARE and 24 % for TACE. TARE patients received fewer treatments (p < 0.001). Fifty-nine (97 %) TARE patients received outpatient treatment. In contrast, 53 (98 %) TACE patients were hospitalized for {>=}1 day (p < 0.001). Compared with TACE, TARE was more likely to induce fatigue (p = 0.003) but less likely to cause fever (p = 0.02). Conclusion. There was no significant difference in efficacy between TARE and TACE. TARE patients reported more fatigue but had less fever than TACE patients. Treatment with TARE required less hospitalization than treatment with TACE. These findings require confirmation in randomized trials.

  5. Endovascular Acute Stroke Treatment Performed by Vascular Interventional Radiologists: Is It Safe and Efficacious?

    SciTech Connect (OSTI)

    Fjetland, Lars, E-mail: lars.fjetland@lyse.net; Roy, Sumit; Kurz, Kathinka D. [Stavanger University Hospital, Department of Radiology (Norway); Larsen, Jan Petter; Kurz, Martin W. [Stavanger University Hospital, Norwegian Centre for Movement Disorders (Norway)

    2012-10-15T23:59:59.000Z

    Purpose: To evaluate the safety and efficacy of neurointerventional procedures in acute stroke patients performed by a team of vascular interventional radiologists in close cooperation with diagnostic neuroradiologists and stroke neurologists and to compare the results with those of previous reports from centres with specialised interventional neuroradiologists. Material and Methods: A total of 39 patients with acute ischemic stroke due to large-vessel occlusion not responding to or not eligible for intravenous thrombolysis were treated with either intra-arterial thrombolysis or mechanical thrombectomy (Penumbra System or solitaire FR thrombectomy system, respectively) and included in our prospective study. Outcomes were measured using the modified Rankin scale after 90 days, and recanalization was assessed by thrombolysis using the myocardial infarction score. Results: Mean patient age was 68.3 {+-} 14.2 years; the average National Institutes of Health Stroke Scale score at hospital admission was 17.2 (SD = 6.2 [n = 38]). Successful recanalization was achieved in 74.4 % of patients. Median time from clinical onset to recanalization was 5 h 11 min. Procedure-related complications occurred in 5 % of patients, and 7.5 % had a symptomatic intracerebral hemorrhage. Of the patients, 22.5 % died within the first 90 postprocedural days, 5 % of these from cerebral causes. Patients who were successfully recanalized had a clinical better outcome at follow-up than those in whom treatment failed. Of the patients, 35.9 % had an mRS score {<=}2 after 90 days. Conclusion: Our results are in line with those in the published literature and show that a treatment strategy with general interventional radiologists performing neurointerventional procedures in acute stroke patients with large vessel occlusions can be achieved to the benefit of patients.

  6. Single and two-photon fluorescence control of Er{sup 3+} ions by phase-shaped femtosecond laser pulse

    SciTech Connect (OSTI)

    Zhang, Shian, E-mail: sazhang@phy.ecnu.edu.cn; Ding, Jingxin; Lu, Chenhui; Jia, Tianqing; Sun, Zhenrong, E-mail: zrsun@phy.ecnu.edu.cn [State Key Laboratory of Precision Spectroscopy, and Department of Physics, East China Normal University, Shanghai 200062 (China)] [State Key Laboratory of Precision Spectroscopy, and Department of Physics, East China Normal University, Shanghai 200062 (China); Xu, Shuwu [State Key Laboratory of Precision Spectroscopy, and Department of Physics, East China Normal University, Shanghai 200062 (China) [State Key Laboratory of Precision Spectroscopy, and Department of Physics, East China Normal University, Shanghai 200062 (China); School of Science, Nantong University, Nantong 226007 (China); Qiu, Jianrong [State Key Laboratory of Luminescent Materials and Devices, and Institute of Optical Communication Materials, South China University of Technology, Wushan Road 381, Guangzhou 510640 (China)] [State Key Laboratory of Luminescent Materials and Devices, and Institute of Optical Communication Materials, South China University of Technology, Wushan Road 381, Guangzhou 510640 (China)

    2014-01-06T23:59:59.000Z

    We experimentally demonstrate the control of the single and two-photon fluorescence (SPF and TPF) in Er{sup 3+} ions by shaping the femtosecond laser pulse with a ? or square phase modulation. With the low laser intensity (8.4?×?10{sup 10}?W/cm{sup 2}), SPF keeps a constant while TPF is effectively suppressed by the two control schemes. With the high laser intensity (1.2?×?10{sup 13}?W/cm{sup 2}), both SPF and TPF are simultaneously enhanced or suppressed by the ? phase modulation, and SPF is enhanced while TPF is effectively suppressed by the square phase modulation. The up/down-conversion fluorescence enhancement, suppression, or tuning by the optical control method can greatly expand its applications in various related fields.

  7. The rotational order–disorder structure of the reversibly photoswitchable red fluorescent protein rsTagRFP

    SciTech Connect (OSTI)

    Pletnev, Sergei, E-mail: pletnevs@mail.nih.gov [Argonne National Laboratory, Argonne, IL 60439 (United States); Argonne National Laboratory, Argonne, IL 60439 (United States); Subach, Fedor V.; Verkhusha, Vladislav V. [Albert Einstein College of Medicine, Bronx, NY 10461 (United States); Dauter, Zbigniew, E-mail: pletnevs@mail.nih.gov [Argonne National Laboratory, Argonne, IL 60439 (United States)

    2014-01-01T23:59:59.000Z

    An analysis of the rotational order–disorder structure of the reversibly photoswitchable red fluorescent protein rsTagRFP is presented. The rotational order–disorder (OD) structure of the reversibly photoswitchable fluorescent protein rsTagRFP is discussed in detail. The structure is composed of tetramers of 222 symmetry incorporated into the lattice in two different orientations rotated 90° with respect to each other around the crystal c axis and with tetramer axes coinciding with the crystallographic twofold axes. The random distribution of alternatively oriented tetramers in the crystal creates the rotational OD structure with statistically averaged I422 symmetry. Despite order–disorder pathology, the structure of rsTagRFP has electron-density maps of good quality for both non-overlapping and overlapping parts of the model. The crystal contacts, crystal internal architecture and a possible mechanism of rotational OD crystal formation are discussed.

  8. A 32-channel photon counting module with embedded auto/cross-correlators for real-time parallel fluorescence correlation spectroscopy

    SciTech Connect (OSTI)

    Gong, S.; Labanca, I.; Rech, I.; Ghioni, M. [Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano (Italy)

    2014-10-15T23:59:59.000Z

    Fluorescence correlation spectroscopy (FCS) is a well-established technique to study binding interactions or the diffusion of fluorescently labeled biomolecules in vitro and in vivo. Fast FCS experiments require parallel data acquisition and analysis which can be achieved by exploiting a multi-channel Single Photon Avalanche Diode (SPAD) array and a corresponding multi-input correlator. This paper reports a 32-channel FPGA based correlator able to perform 32 auto/cross-correlations simultaneously over a lag-time ranging from 10 ns up to 150 ms. The correlator is included in a 32 × 1 SPAD array module, providing a compact and flexible instrument for high throughput FCS experiments. However, some inherent features of SPAD arrays, namely afterpulsing and optical crosstalk effects, may introduce distortions in the measurement of auto- and cross-correlation functions. We investigated these limitations to assess their impact on the module and evaluate possible workarounds.

  9. In vivo monitoring of toxic metals: assessment of neutron activation and x-ray fluorescence techniques

    SciTech Connect (OSTI)

    Ellis, K.J.

    1986-01-01T23:59:59.000Z

    To date, cadmium, lead, aluminum, and mercury have been measured in vivo in humans. The possibilities of monitoring other toxic metals have also been demonstrated, but no human studies have been performed. Neutron activation analysis appears to be most suitable for Cd and Al measurements, while x-ray fluorescence is ideally suited for measurement of lead in superficial bone. Filtered neutron beams and polarized x-ray sources are being developed which will improve in vivo detection limits. Even so, several of the current facilities are already suitable for use in epidemiological studies of selected populations with suspected long-term low-level ''environmental'' exposures. Evaluation and diagnosis of patients presenting with general clinical symptoms attributable to possible toxic metal exposure may be assisted by in vivo examination. Continued in vivo monitoring of industrial workers, especially follow-up measurements, will provide the first direct assessment of changes in body burden and a direct measure of the biological life-times of these metals in humans. 50 refs., 4 figs., 2 tabs.

  10. Isotope shifts of natural Sr+ measured by laser fluorescence in a sympathetically cooled Coulomb crystal

    E-Print Network [OSTI]

    Brice Dubost; Romain Dubessy; Benjamin Szymanski; Samuel Guibal; Jean-Pierre Likforman; Luca Guidoni

    2014-02-14T23:59:59.000Z

    We measured by laser spectroscopy the isotope shifts between naturally-occurring even-isotopes of strontium ions for both the $5s\\,\\,^2S_{1/2}\\to 5p\\,\\,^2P_{1/2}$ (violet) and the $4d\\,\\,^2D_{3/2}\\to 5p\\,\\,^2P_{1/2}$ (infrared) dipole-allowed optical transitions. Fluorescence spectra were taken by simultaneous measurements on a two-component Coulomb crystal in a linear Paul trap containing $10^3$--$10^4$ laser-cooled Sr$^+$ ions. The isotope shifts are extracted from the experimental spectra by fitting the data with the analytical solution of the optical Bloch equations describing a three-level atom in interaction with two laser beams. This technique allowed us to increase the precision with respect to previously reported data obtained by optogalvanic spectroscopy or fast atomic-beam techniques. The results for the $5s\\,\\,^2S_{1/2}\\to 5p\\,\\,^2P_{1/2}$ transition are $\

  11. Quality studies of the data taking conditions for the Auger Fluorescence Detector

    E-Print Network [OSTI]

    R. Caruso; R. Fonte; A. Insolia; S. Petrera; J. Rodriguez Martino; Pierre Auger Collaboration

    2005-07-06T23:59:59.000Z

    As more than half of the Fluorescence Detector (FD) of the Auger Observatory is completed, data taking is becoming a routine job. It is then necessary to follow strict procedures to assure the quality of the data. An overview of the data taking methods is given. The nature of the FD background signal is due to the night sky brightness (stars and planet faint light, moonlight, twilight, airglow, zodiacal and artificial light) and to the electronic background (photomultiplier and electronic noise). The analysis of the fluctuations in the FADC signal (variance analysis), directly proportional to the background mean light level, performed for each night of data taking is used to monitor the FD background signal. The data quality is analysed using different techniques, described in detail. Examples of trigger rates, number of stereo events, dead time due to moonlight, weather or hardware problems are given. The analysis comprises several months of data taking, giving an overview of the FD capabilities, performance and allowing a systematic study of data and their correlation with the environment.

  12. Quantum-jumps and photon-statistic in fluorescent systems coupled to classically fluctuating reservoirs

    E-Print Network [OSTI]

    Adrian A. Budini

    2010-05-20T23:59:59.000Z

    In this paper, we develop a quantum-jump approach for describing the photon-emission process of single fluorophore systems coupled to complex classically fluctuating reservoirs. The formalism relies on an open quantum system approach where the dynamic of the system and the reservoir fluctuations are described through a density matrix whose evolution is defined by a Lindblad rate equation. For each realization of the photon measurement processes it is possible to define a conditional system state (stochastic density matrix) whose evolution depends on both the photon detection events and the fluctuations between the configurational states of the reservoir. In contrast to standard fluorescent systems the photon-to-photon emission process is not a renewal one, being defined by a (stochastic) waiting time distribution that in each recording event parametrically depends on the conditional state. The formalism allows calculating experimental observables such as the full hierarchy of joint probabilities associated to the time intervals between consecutive photon recording events. These results provide a powerful basis for characterizing different situations arising in single-molecule spectroscopy, such as spectral fluctuations, lifetime fluctuations, and light assisted processes.

  13. Communication: Angular momentum alignment and fluorescence polarization of alkali atoms photodetached from helium nanodroplets

    SciTech Connect (OSTI)

    Hernando, Alberto; Beswick, J. Alberto; Halberstadt, Nadine [LCAR-IRSAMC, Université Toulouse 3 - Paul Sabatier and CNRS, 31062 Toulouse (France)] [LCAR-IRSAMC, Université Toulouse 3 - Paul Sabatier and CNRS, 31062 Toulouse (France)

    2013-12-14T23:59:59.000Z

    The theory of photofragments angular momentum polarization is applied to the photodetachment of an electronically excited alkali atom from a helium nanocluster (N = 200). The alignment of the electronic angular momentum of the bare excited alkali atoms produced is calculated quantum mechanically by solving the excited states coupled equations with potentials determined by density functional theory (DFT). Pronounced oscillations as a function of excitation energy are predicted for the case of Na@(He){sub 200}, in marked contrast with the absorption cross-section and angular distribution of the ejected atoms which are smooth functions of the energy. These oscillations are due to quantum interference between different coherently excited photodetachment pathways. Experimentally, these oscillations should be reflected in the fluorescence polarization and polarization-resolved photoelectron yield of the ejected atoms, which are proportional to the electronic angular momentum alignment. In addition, this result is much more general than the test case of NaHe{sub 200} studied here. It should be observable for larger droplets, for higher excited electronic states, and for other alkali as well as for alkali-earth atoms. Detection of these oscillations would show that the widely used pseudo-diatomic model can be valid beyond the prediction of absorption spectra and could help in interpreting parts of the dynamics, as already hinted by some experimental results on angular anisotropy of bare alkali fragments.

  14. Subwavenumber charge-coupled device spectrometer calibration using molecular iodine laser-induced fluorescence

    SciTech Connect (OSTI)

    Lambert, Joseph G. [Department of Physics, Drexel University, Philadelphia, Pennsylvania 19104 (United States); Hernandez-Diaz, Carlos; Williamson, J. Charles [Department of Chemistry, Willamette University, Salem, Oregon 97301 (United States)

    2010-01-15T23:59:59.000Z

    Spectrometers configured with charge-coupled devices (CCD) or other array-based detectors require calibration to convert from the pixel coordinate to a spectral coordinate. A CCD calibration method well suited for Raman spectroscopy has been developed based on the 514.5 nm Ar{sup +} laser-induced fluorescence (LIF) spectrum of room-temperature molecular iodine vapor. Over 360 primary and secondary I{sub 2} LIF calibration lines spanning 510-645 nm were identified as calibrant peaks using an instrumental resolution of 1 cm{sup -1}. Two instrument calibration functions were evaluated with these peaks: a second-order polynomial and a function derived from simple optomechanical considerations. The latter function provided better fitting characteristics. Calibration using I{sub 2} LIF was tested with measurements of both laser light scattering and Raman spectra. The I{sub 2} LIF reference spectra and the signal spectra were recorded simultaneously, with no cross talk, by separating the two signals spatially along the vertical axis of the CCD imager. In this way, every CCD image could be independently calibrated. An accuracy and a precision of {+-}0.05 cm{sup -1} were achieved with this calibration technique.

  15. Synchrotron-based X-ray fluorescence imaging and elemental mapping from biological samples

    SciTech Connect (OSTI)

    D Rao; M Swapna; R Cesareo; A Brunetti; T Akatsuka; T Yuasa; T Takeda; G Gigante

    2011-12-31T23:59:59.000Z

    The present study utilized the new hard X-ray microspectroscopy beamline facility, X27A, available at NSLS, BNL, USA, for elemental mapping. This facility provided the primary beam in a small spot of the order of {approx}10 {mu}m, for focussing. With this spatial resolution and high flux throughput, the synchrotron-based X-ray fluorescent intensities for Mn, Fe, Zn, Cr, Ti and Cu were measured using a liquid-nitrogen-cooled 13-element energy-dispersive high-purity germanium detector. The sample is scanned in a 'step-and-repeat' mode for fast elemental mapping measurements and generated elemental maps at 8, 10 and 12 keV, from a small animal shell (snail). The accumulated trace elements, from these biological samples, in small areas have been identified. Analysis of the small areas will be better suited to establish the physiology of metals in specific structures like small animal shell and the distribution of other elements.

  16. Attenuation Correction of L-shell X-ray Fluorescence Computed Tomography Imaging

    E-Print Network [OSTI]

    Long, Liu; Bo, Ma; Qing, Xu; Lingtong, Yan; Li, Li; Songlin, Feng; Xiangqian, Feng

    2014-01-01T23:59:59.000Z

    X-ray Fluorescence Computed Tomography(XFCT) is a prevalent experimental technique which is utilized to investigate the spatial distribution of elements in sample. The sensitivity of L-shell XFCT of some elements is lower than that of K-shell XFCT. However, the image reconstruction for this technique has much more problems than that of transmission tomography, one of which is self-absorption. In the present work, a novel strategy was developed to deal with such problems. But few researches are concerned on attenuation correction of L-shell XFCT that are essential to get accurate reconstructed image. We make use of the known quantities and the unknown elemental concentration of interest to express the unknown attenuation maps. And then the attenuation maps are added in the contribution value of the pixel in MLEM reconstruction method. Results indicate that the relative error is less than 14.1%, which is proved this method can correct L-shell XFCT very well.

  17. Hard X-rays and Fluorescent Iron Emission from the Embedded Infrared Cluster in NGC 2071

    E-Print Network [OSTI]

    Stephen L. Skinner; Audrey E. Simmons; Marc Audard; Manuel Guedel

    2006-12-19T23:59:59.000Z

    We present first results of XMM-Newton X-ray observations of the infrared cluster lying near the NGC 2071 reflection nebula in the Orion B region. This cluster is of interest because it is one of the closest regions known to harbor embedded high-mass stars. We report the discovery of hard X-ray emission from the dense central NGC 2071-IR subgroup which contains at least three high-mass young stellar objects (NGC 2071 IRS-1, IRS-2, and IRS-3). A prominent X-ray source is detected within 1 arcsecond of the infrared source IRS-1, which is thought to drive a powerful bipolar molecular outflow. The X-ray spectrum of this source is quite unusual compared to the optically thin plasma spectra normally observed in young stellar objects (YSOs). The spectrum is characterized by a hard broad-band continuum plus an exceptionally broad emission line at approximately 6.4 keV from neutral or near-neutral iron. The fluorescent Fe line likely originates in cold material near the embedded star (i.e. a disk or envelope) that is irradiated by the hard heavily-absorbed X-ray source.

  18. Fluorescence analysis can identify movable oil in self-sourcing reservoirs

    SciTech Connect (OSTI)

    Calhoun, G.G. [Calhoun (Gerry G.), Midland, TX (United States)

    1995-06-05T23:59:59.000Z

    The recent surge of activity involving self-sourcing reservoirs and horizontal drilling recognizes a little tapped niche in the domestic energy mix. Such prolific pays as the Cretaceous Bakken and Austin Chalk have drawn research interest and large amounts of investment capital. Fluorescence analysis can discern movable oil--as opposed to exhausted source rock--in such reservoirs with an inexpensive test. Other potential targets are the Cretaceous Mesaverde in the Piceance basin, Devonian New Albany shale in Kentucky, Devonian Antrim shale in the Michigan basin, and the Cretaceous Niobrara, Mancos, and Pierre formations in Colorado and New Mexico. To insure success in this niche this key question must be answered positively: Is movable oil present in the reservoir? Even if tectonic studies verify a system of open fractures, sonic logs confirm overpressuring in the zone, and resistivity logs document the maturity of the source, the ultimate question remains: Is movable oil in the fractures available to flow to the borehole? The paper explains a technique that will answer these questions.

  19. Note: A portable, light-emitting diode-based ruby fluorescence spectrometer for high-pressure calibration

    SciTech Connect (OSTI)

    Feng Yejun [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

    2011-04-15T23:59:59.000Z

    Ruby (Al{sub 2}O{sub 3}, with {approx}0.5 wt. % Cr doping) is one of the most widely used manometers at the giga-Pascal scale. Traditionally, its fluorescence is excited with intense laser sources. Here, I present a simple, robust, and portable design that employs light-emitting diodes (LEDs) instead. This LED-based system is safer in comparison with laser-based ones.

  20. Solvent viscosity effect on quenching rate constants of phenophytin a fluorescence by quinones. Role of non-stationary effects

    SciTech Connect (OSTI)

    Kapinus, E.I.; Dilung II.; Kucherova, I.Y.; Kuz'min, M.G.; Zartsev, N.K.

    1986-11-01T23:59:59.000Z

    The fluorescence quenching of phenophytin a by quinones in different solvents has been studied with a steady-state and pulse photoexcitation. The quenching in alcohols is caused by complexes which are spectrally undetectable. In other solvents the quenching is dynamic. The effect of viscosity on the quenching rate has been studied. It has been found that the non-stationary effects play a substantial role in the quenching process.

  1. 0 1995 Wiley-Liss, Inc. Cytometry 20:14-18 (1995) Fluorescent Erythrocyte Ghosts as Standards for

    E-Print Network [OSTI]

    . MATERIALS AND METHODS Production of Fluorescent Erythrocyte Ghosts We produced erythrocyte ghosts at 800g in a clinical centrifuge at 4°C. After decanting the superna- tant, we resuspended the pellet and mixing of the pellet in ice cold 5P75 (5 mM NaPO,, pH 7.5). We stored this suspension on ice for 10min

  2. A matter of collection and detection for intraoperative and noninvasive near-infrared fluorescence molecular imaging: To see or not to see?

    SciTech Connect (OSTI)

    Zhu, Banghe; Rasmussen, John C.; Sevick-Muraca, Eva M., E-mail: Eva.Sevick@uth.tmc.edu [Center for Molecular Imaging, The Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center, Houston, Texas 77030 (United States)

    2014-02-15T23:59:59.000Z

    Purpose: Although fluorescence molecular imaging is rapidly evolving as a new combinational drug/device technology platform for molecularly guided surgery and noninvasive imaging, there remains no performance standards for efficient translation of “first-in-humans” fluorescent imaging agents using these devices. Methods: The authors employed a stable, solid phantom designed to exaggerate the confounding effects of tissue light scattering and to mimic low concentrations (nM–pM) of near-infrared fluorescent dyes expected clinically for molecular imaging in order to evaluate and compare the commonly used charge coupled device (CCD) camera systems employed in preclinical studies and in human investigational studies. Results: The results show that intensified CCD systems offer greater contrast with larger signal-to-noise ratios in comparison to their unintensified CCD systems operated at clinically reasonable, subsecond acquisition times. Conclusions: Camera imaging performance could impact the success of future “first-in-humans” near-infrared fluorescence imaging agent studies.

  3. Ultrafast Fluorescence Relaxation Spectroscopy of 6,7-Dimethyl-(8-ribityl)-lumazine and Riboflavin, Free and Bound to Antenna Proteins from Bioluminescent Bacteria

    E-Print Network [OSTI]

    van Stokkum, Ivo

    Ultrafast Fluorescence Relaxation Spectroscopy of 6,7-Dimethyl-(8-ribityl)-lumazine and Riboflavin-(8-ribityl)-lumazine (lumazine) and riboflavin in an aqueous buffer and both ligands when

  4. Visualization of nitric oxide production in the mouse main olfactory bulb by a cell-trappable copper(II) fluorescent probe

    E-Print Network [OSTI]

    McQuade, Lindsey E.

    We report the visualization of NO production using fluorescence in tissue slices of the mouse main olfactory bulb. This discovery was possible through the use of a novel, cell-trappable probe for intracellular nitric oxide ...

  5. X-Ray Fluorescence (XRF) Analysis of Obsidian Artifacts from the Grand Canal, Casa Buena, and Pueblo Grande Hohokam Sites, Central Arizona

    E-Print Network [OSTI]

    Shackley, M. Steven

    1987-01-01T23:59:59.000Z

    62:426-437. SOUTHWEST XRF PAPER Table 1. X-ray fluorescencet. X-RAY FLUORESCENCE (XRF) ANALYSIS OF OBSIDIAN ARTIFACTSSt- Figure 1. Ternary plot of XRF net intensity ratios for

  6. M13 Phage-Functionalized Single-Walled Carbon Nanotubes As Nanoprobes for Second Near-Infrared Window Fluorescence Imaging of Targeted Tumors

    E-Print Network [OSTI]

    Yi, Hyunjung

    Second near-infrared (NIR) window light (950–1400 nm) is attractive for in vivo fluorescence imaging due to its deep penetration depth in tissues and low tissue autofluorescence. Here we show genetically engineered ...

  7. Investigation of measuring hazardous substances in printed circuit boards using the micro-focus X-ray fluorescence screening

    E-Print Network [OSTI]

    Fu, M L; Fakhrtdinov, R; Grigoriev, M; Quan, B S; Le, Z C; Roshchupkin, D

    2014-01-01T23:59:59.000Z

    Printed circuit boards (PCBs) are widely used in most electrical and electronic equipments or products. Hazardous substances such as Pb, Hg, Cd, etc, can be present in high concentrations in PCBs and the degradation and release of these substances poses a huge threat to humans and the environment. To investigation the chemical composition of PCBs in domestic market of China, a practical micro-focus X-ray fluorescence system is setup to make the elements analysis, especially for detecting hazardous substances. Collimator is adopted to focus the X-ray emitted from X-ray tube. BRUKER X-ray detector with proportional counter is used to detect the emitted fluorescence from the PCB samples. Both single layer PCB samples and double layers PCB samples made of epoxy glass fiber are purchased from the domestic market of China. Besides, a MC55 wireless communication module made by SIEMENS in Germany is used as the reference material. Experimental results from the fluorescence spectrums of the testing points of PCB sampl...

  8. Method of using a nuclear magnetic resonance spectroscopy standard. [SO/sub 2/ in gases by fluorescence

    DOE Patents [OSTI]

    Spicer, L.D.; Bennett, D.W.; Davis, J.F.

    1983-05-09T23:59:59.000Z

    (CH/sub 3/)/sub 3/SiNSO is produced by the reaction of ((CH/sub 3/)/sub 3/SI)/sub 2/NH with SO/sub 2/. Also produced in the reaction are ((CH/sub 3/)/sub 3/Si)/sub 2/O and a new solid compound (NH/sub 4/)((CH/sub 3/)/sub 3/SiOSO/sub 2/). Both (CH/sub 3/)/sub 3/SiNSO and (NH/sub 4/)((CH/sub 3/)/sub 3/SiOSO/sub 2/) have fluorescent properties. The reaction of the subject invention is used in a method of measuring the concentration of SO/sub 2/ pollutants in gases. By the method, a sample of gas is bubbled through a solution of ((CH/sub 3/)/sub 3/Si)/sub 2/NH, whereby any SO/sub 2/ present in the gas will react to produce the two fluorescent products. The measured fluorescence of these products can then be used to calculate the concentration of SO/sub 2/ in the original gas sample. The solid product (NH/sub 4/)((CH/sub 3/)/sub 3/SiOSO/sub 2/) may be used as a standard in solid state NMR spectroscopy, wherein the resonance peaks of either /sup 1/H, /sup 13/C, /sup 15/N, or /sup 29/Si may be used as a reference.

  9. X-ray crystal structure and properties of Phanta, a weakly fluorescent photochromic GFP-like protein

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Paul, Craig Don; Traore, Daouda A. K.; Olsen, Seth; Devenish, Rodney J.; Close, Devin W.; Bell, Toby D. M.; Bradbury, Andrew; Wilce, Matthew C. J.; Prescott, Mark

    2015-04-29T23:59:59.000Z

    Phanta is a reversibly photoswitching chromoprotein (?F, 0.003), useful for pcFRET, that was isolated from a mutagenesis screen of the bright green fluorescent eCGP123 (?F, 0.8). We have investigated the contribution of substitutions at positions His193, Thr69 and Gln62, individually and in combination, to the optical properties of Phanta. Single amino acid substitutions at position 193 resulted in proteins with very low ?F, indicating the importance of this position in controlling the fluorescence efficiency of the variant proteins. The substitution Thr69Val in Phanta was important for supressing the formation of a protonated chromophore species observed in some His193 substituted variants,more »whereas the substitution Gln62Met did not significantly contribute to the useful optical properties of Phanta. X-ray crystal structures for Phanta (2.3 Å), eCGP123T69V (2.0 Å) and eCGP123H193Q (2.2 Å) in their non-photoswitched state were determined, revealing the presence of a cis-coplanar chromophore. We conclude that changes in the hydrogen-bonding network supporting the cis-chromophore, and its contacts with the surrounding protein matrix, are responsible for the low fluorescence emission of eCGP123 variants containing a His193 substitution.« less

  10. Electronic structure of the 4d transition metal carbides: Dispersed fluorescence spectroscopy of MoC, RuC, and PdC

    E-Print Network [OSTI]

    Morse, Michael D.

    C, RuC, and PdC Ryan S. DaBell,a) Raymond G. Meyer,b) and Michael D. Morsec) Department of Chemistry fluorescence studies of the diatomic molecules MoC, RuC, and PdC are reported. New states identified in Mo are observed by dispersed fluorescence in PdC. The ground state is found to be ... 2 4 12 2 , 1

  11. The Efficacy of Ultraviolet Radiation for Sterilizing Tools Used for Surgically Implanting Transmitters into Fish

    SciTech Connect (OSTI)

    Walker, Ricardo W.; Markillie, Lye Meng; Colotelo, Alison HA; Gay, Marybeth E.; Woodley, Christa M.; Brown, Richard S.

    2013-02-28T23:59:59.000Z

    Telemetry is frequently used to examine the behavior of fish, and the transmitters used are normally surgically implanted into the coelom of fish. Implantation requires the use of surgical tools such as scalpels, forceps, needle holders, and sutures. When several fish are implanted consecutively for large telemetry studies, it is common for surgical tools to be sterilized or, at minimum, disinfected between each use so that pathogens that may be present are not spread among fish. However, autoclaving tools can take a long period of time, and chemical sterilants or disinfectants can be harmful to both humans and fish and have varied effectiveness. Ultraviolet (UV) radiation is commonly used to disinfect water in aquaculture facilities. However, this technology has not been widely used to sterilize tools for surgical implantation of transmitters in fish. To determine its efficacy for this application, Pacific Northwest National Laboratory researchers used UV radiation to disinfect surgical tools (i.e., forceps, needle holder, stab scalpel, and suture) that were exposed to one of four aquatic organisms that typically lead to negative health issues for salmonids. These organisms included Aeromonas salmonicida, Flavobacterium psychrophilum, Renibacterium salmoninarum, and Saprolegnia parasitica. Surgical tools were exposed to the bacteria by dipping them into a confluent suspension of three varying concentrations (i.e., low, medium, high). After exposure to the bacterial culture, tools were placed into a mobile Millipore UV sterilization apparatus. The tools were then exposed for three different time periods—2, 5, or 15 min. S. parasitica, a water mold, was tested using an agar plate method and forceps-pinch method. UV light exposures of 5 and 15 min were effective at killing all four organisms. UV light was also effective at killing Geobacillus stearothermophilus, the organism used as a biological indicator to verify effectiveness of steam sterilizers. These techniques appear to provide a quick alternative disinfection technique for some surgical tools that is less harmful to both humans and fish while not producing chemical waste. However, we do not recommend using these methods with tools that have overlapping parts or other structures that cannot be directly exposed to UV light such as needle holders.

  12. Chemoembolization of Hepatocellular Carcinoma with Hepasphere 30–60 ?m. Safety and Efficacy Study

    SciTech Connect (OSTI)

    Malagari, Katerina, E-mail: kmalag@otenet.gr [University of Athens, 2nd Department of Radiology (Greece); Pomoni, Maria, E-mail: mpomoni@mail.gr [University of Athens, Imaging and Research Unit (Greece); Moschouris, Hippokratis, E-mail: hipmosch@gmail.com [Tzanion Hospital, Department of Radiology (Greece); Kelekis, Alexios, E-mail: akelekis@cc.uoa.gr [University of Athens, 2nd Department of Radiology (Greece); Charokopakis, Angelos, E-mail: axarok@gmail.com; Bouma, Evanthia, E-mail: boumaevanthia@gmail.com; Spyridopoulos, Themistoklis [University of Athens, Imaging and Research Unit (Greece); Chatziioannou, Achilles, E-mail: ahatzi@cc.uoa.gr [University of Athens, 2nd Department of Radiology (Greece); Sotirchos, Vlasios, E-mail: sotirchos@hotmail.com [University of Athens, Imaging and Research Unit (Greece); Karampelas, Theodoros, E-mail: ctamvakop@bioacademy.gr; Tamvakopoulos, Constantin, E-mail: ctamvakop@bioacademy.gr [Research Academy of University of Athens (Greece); Filippiadis, Dimitrios, E-mail: dfilippiadis@yahoo.gr [University of Athens, 2nd Department of Radiology (Greece); Karagiannis, Enangelos, E-mail: kmalag@otenet.gr [University of Athens, Imaging and Research Unit (Greece); Marinis, Athanasios, E-mail: drmarinis@gmail.com [Tzanion Hospital, 1st Department of Surgery (Greece); Koskinas, John, E-mail: koskinas@ath.forthnet.gr [University of Athens, 2nd Department of Internal Medicine and Hepatology (Greece); Kelekis, Dimitrios A., E-mail: dkelekis@med.uoa.gr [University of Athens, Imaging and Research Unit, 2nd Department of Radiology (Greece)

    2013-11-22T23:59:59.000Z

    Background: This study examined the safety, pharmacokinetics, and efficacy of transarterial chemoembolization of hepatocellular carcinoma (HCC) using a newly developed size of a superabsorbent polymer drug-eluting embolic material.MethodsForty-five patients with documented HCC (Child–Pugh score A/B: 55.5 %/44.5 %) were embolized with HepaSphere microspheres 30–60 ?m with escalation of lesion, dose, and frequency of re-embolization. Local response was evaluated with modified response evaluation criteria in solid tumors (mRECIST). Plasma levels of doxorubicin were measured in 24 patients at baseline and at 5, 20, 40, 60, and 120 min, at 6, 24, and 48 h, and at 7 days, respectively, to determine doxorubicin in plasma (Cmax) and area under the curve (AUC). Measurements of three patients who underwent lipiodol-based conventional chemoembolization (c-TACE) were also performed.ResultsTACE with HepaSphere was well tolerated with an acceptable safety profile and no 30-day mortality. Response rates were calculated on intention-to-treat basis with complete response (CR) in 17.8 % reaching 22.2 % for the target lesion. Overall partial response (PR) was seen in 51.1 %, stable disease in 20 %, and progressive disease in 11.1 % of patients. Overall objective response (CR + PR), including patients treated at all dosages of doxorubicin, was seen in 68.9 % of cases. After a median follow-up of 15.6 months, 1-year survival is 100 %. Doxorubicin AUC was significantly lower in patients with HepaSphere 30–60 ?m (35,195 ± 27,873 ng × min/ml) than in patients with conventional TACE (103,960 ± 16,652 ng × min/ml; p = 0.009). Cmax was also significantly lower with HepaSphere 30–60 ?m (83.9 ± 32.1 ng/ml) compared with c-TACE (761.3 ± 58.8 ng/ml; p = 0.002).ConclusionHepaSphere 30–60 ?m is an effective drug-eluting embolic material with a favourable pharmacokinetic profile.

  13. Crystallographic study of red fluorescent protein eqFP578 and its far-red variant Katushka reveals opposite pH-induced isomerization of chromophore

    SciTech Connect (OSTI)

    Pletneva, Nadya V.; Pletnev, Vladimir Z.; Shemiakina, Irina I.; Chudakov, Dmitriy M.; Artemyev, Igor; Wlodawer, Alexander; Dauter, Zbigniew; Pletnev, Sergei (Russ. Acad. Sci.); (SAIC); (NCI)

    2012-08-10T23:59:59.000Z

    The wild type red fluorescent protein eqFP578 (from sea anemone Entacmaea quadricolor, {lambda}{sub ex} = 552 nm, {lambda}{sub em} = 578 nm) and its bright far-red fluorescent variant Katushka ({lambda}{sub ex} = 588 nm, {lambda}{sub em} = 635 nm) are characterized by the pronounced pH dependence of their fluorescence. The crystal structures of eqFP578f (eqFP578 with two point mutations improving the protein folding) and Katushka have been determined at the resolution ranging from 1.15 to 1.85 {angstrom} at two pH values, corresponding to low and high level of fluorescence. The observed extinguishing of fluorescence upon reducing pH in eqFP578f and Katushka has been shown to be accompanied by the opposite trans-cis and cis-trans chromophore isomerization, respectively. Asn143, Ser158, His197 and Ser143, Leu174, and Arg197 have been shown to stabilize the respective trans and cis fluorescent states of the chromophores in eqFP578f and Katushka at higher pH. The cis state has been suggested as being primarily responsible for the observed far-red shift of the emission maximum of Katushka relative to that of eqFP578f.

  14. New Homogeneous Standards by Atomic Layer Deposition for Synchrotron X-ray Fluorescence and Absorption Spectroscopies.

    SciTech Connect (OSTI)

    Butterworth, A.L.; Becker, N.; Gainsforth, Z.; Lanzirotti, A.; Newville, M.; Proslier, T.; Stodolna, J.; Sutton, S.; Tyliszczak, T.; Westphal, A.J.; Zasadzinski, J. (UCB)

    2012-03-13T23:59:59.000Z

    Quantification of synchrotron XRF analyses is typically done through comparisons with measurements on the NIST SRM 1832/1833 thin film standards. Unfortunately, these standards are inhomogeneous on small scales at the tens of percent level. We are synthesizing new homogeneous multilayer standards using the Atomic Layer Deposition technique and characterizing them using multiple analytical methods, including ellipsometry, Rutherford Back Scattering at Evans Analytical, Synchrotron X-ray Fluorescence (SXRF) at Advanced Photon Source (APS) Beamline 13-ID, Synchrotron X-ray Absorption Spectroscopy (XAS) at Advanced Light Source (ALS) Beamlines 11.0.2 and 5.3.2.1 and by electron microscopy techniques. Our motivation for developing much-needed cross-calibration of synchrotron techniques is borne from coordinated analyses of particles captured in the aerogel of the NASA Stardust Interstellar Dust Collector (SIDC). The Stardust Interstellar Dust Preliminary Examination (ISPE) team have characterized three sub-nanogram, {approx}1{micro}m-sized fragments considered as candidates to be the first contemporary interstellar dust ever collected, based on their chemistries and trajectories. The candidates were analyzed in small wedges of aerogel in which they were extracted from the larger collector, using high sensitivity, high spatial resolution >3 keV synchrotron x-ray fluorescence spectroscopy (SXRF) and <2 keV synchrotron x-ray transmission microscopy (STXM) during Stardust ISPE. The ISPE synchrotron techniques have complementary capabilities. Hard X-ray SXRF is sensitive to sub-fg mass of elements Z {ge} 20 (calcium) and has a spatial resolution as low as 90nm. X-ray Diffraction data were collected simultaneously with SXRF data. Soft X-ray STXM at ALS beamline 11.0.2 can detect fg-mass of most elements, including cosmochemically important oxygen, magnesium, aluminum and silicon, which are invisible to SXRF in this application. ALS beamline 11.0.2 has spatial resolution better than 25 nm. Limiting factors for Stardust STXM analyses were self-imposed limits of photon dose due to radiation damage concerns, and significant attenuation of <1500 eV X-rays by {approx}80{micro}m thick, {approx}25 mg/cm{sup 3} density silica aerogel capture medium. In practice, the ISPE team characterized the major, light elements using STXM (O, Mg, Al, Si) and the heavier minor and trace elements using SXRF. The two data sets overlapped only with minor Fe and Ni ({approx}1% mass abundance), providing few quantitative cross-checks. New improved standards for cross calibration are essential for consortium-based analyses of Stardust interstellar and cometary particles, IDPs. Indeed, they have far reaching application across the whole synchrotron-based analytical community. We have synthesized three ALD multilayers simultaneously on silicon nitride membranes and silicon and characterized them using RBS (on Si), XRF (on Si{sub 3}N{sub 4}) and STXM/XAS (holey Si{sub 3}N{sub 4}). The systems we have started to work with are Al-Zn-Fe and Y-Mg-Er. We have found these ALD multi-layers to be uniform at {micro}m- to nm scales, and have found excellent consistency between four analytical techniques so far. The ALD films can also be used as a standard for e-beam instruments, eg., TEM EELS or EDX. After some early issues with the consistency of coatings to the back-side of the membrane windows, we are confident to be able to show multi-analytical agreement to within 10%. As the precision improves, we can use the new standards to verify or improve the tabulated cross-sections.

  15. Two photon absorption laser induced fluorescence measurements of neutral density in a helicon plasma

    SciTech Connect (OSTI)

    Galante, M. E.; Magee, R. M.; Scime, E. E. [Department of Physics, West Virginia University, Morgantown, West Virginia 26506 (United States)] [Department of Physics, West Virginia University, Morgantown, West Virginia 26506 (United States)

    2014-05-15T23:59:59.000Z

    We have developed a new diagnostic based on two-photon absorption laser induced fluorescence (TALIF). We use a high intensity (5?MW/cm{sup 2}), narrow bandwidth (0.1?cm{sup ?1}) laser to probe the ground state of neutral hydrogen, deuterium and krypton with spatial resolution better than 0.2?cm, a time resolution of 10?ns, and a measurement cadence of 20?Hz. Here, we describe proof-of-principle measurements in a helicon plasma source that demonstrate the TALIF diagnostic is capable of measuring neutral densities spanning four orders of magnitude; comparable to the edge neutral gradients predicted in the DIII-D tokamak pedestal. The measurements are performed in hydrogen and deuterium plasmas and absolute calibration is accomplished through TALIF measurements in neutral krypton. The optical configuration employed is confocal, i.e., both light injection and collection are accomplished with a single lens through a single optical port in the vacuum vessel. The wavelength resolution of the diagnostic is sufficient to separate hydrogen and deuterium spectra and we present measurements from mixed hydrogen and deuterium plasmas that demonstrate isotopic abundance measurements are feasible. Time resolved measurements also allow us to explore the evolution of the neutral hydrogen density and temperature and effects of wall recycling. We find that the atomic neutral density grows rapidly at the initiation of the discharge, reaching the steady-state value within 1?ms. Additionally, we find that neutral hydrogen atoms are born with 0.08?eV temperatures, not 2?eV as is typically assumed.

  16. Hard X-ray Fluorescence Measurements of Heteroepitaxial Solid Oxide Fuel Cell Cathode Materials

    SciTech Connect (OSTI)

    Davis, Jacob N.; Miara, Lincoln J.; Saraf, Laxmikant V.; Kaspar, Tiffany C.; Gopalan, Srikanth; Pal, Uday B.; Woicik, Joseph C.; Basu, Soumendra N.; Ludwig, Karl F.

    2012-12-01T23:59:59.000Z

    Commonly, SOFCs are operated at high temperatures (above 800°C). At these temperatures expensive housing is needed to contain an operating stack as well as coatings to contain the oxidation of the metallic interconnects. Lowering the temperature of an operating device would allow for more conventional materials to be used, thus lowering overall cost. Understanding the surface chemical states of cations in the surface of the SOFC cathode is vital to designing a system that will perform well at lower temperatures. The samples studied were grown by pulsed laser deposition (PLD) at the Environmental Molecular Sciences Laboratory (EMSL) at Pacific Northwest National Laboratory (PNNL). 20% strontium doped lanthanum manganite (LSM-20) was grown on YSZ and NGO (neodymium gallate). The films on YSZ have a fiber texture. LSM-20 on NGO is heteroepitaxial. Lanthanum strontium cobalt ferrite (LSCF-6428) films were grown on LAO and YSZ with a GDC barrier layer. Total X-ray Reflection Fluorescence (TXRF) was used to depth profile the samples. In a typical experiment, the angle of the incident beam is varied though the critical angle. Below the critical angle, the x-ray decays as an evanescent wave and will only penetrate the top few nanometers. TXRF experiments done on LSM films have suggested strontium segregates to the surface and form strontium enriched nanoparticles (1). It should be pointed out that past studies have focused on 30% strontium A-site doping, but this project uses 20% strontium doped lanthanum manganite. XANES and EXAFS data were taken as a function of incoming angle to probe composition as a function of depth. XANES spectra can be difficult to analyze fully. For other materials density functional theory calculations compared to near edge measurements have been a good way to understand the 3d valence electrons (2).

  17. THE SAP3 COMPUTER PROGRAM FOR QUANTITATIVE MULTIELEMENT ANALYSIS BY ENERGY DISPERSIVE X-RAY FLUORESCENCE

    SciTech Connect (OSTI)

    Nielson,, K. K.; Sanders,, R. W.

    1982-04-01T23:59:59.000Z

    SAP3 is a dual-function FORTRAN computer program which performs peak analysis of energy-dispersive x-ray fluorescence spectra and then quantitatively interprets the results of the multielement analysis. It was written for mono- or bi-chromatic excitation as from an isotopic or secondary excitation source, and uses the separate incoherent and coherent backscatter intensities to define the bulk sample matrix composition. This composition is used in performing fundamental-parameter matrix corrections for self-absorption, enhancement, and particle-size effects, obviating the need for specific calibrations for a given sample matrix. The generalized calibration is based on a set of thin-film sensitivities, which are stored in a library disk file and used for all sample matrices and thicknesses. Peak overlap factors are also determined from the thin-film standards, and are stored in the library for calculating peak overlap corrections. A detailed description is given of the algorithms and program logic, and the program listing and flow charts are also provided. An auxiliary program, SPCAL, is also given for use in calibrating the backscatter intensities. SAP3 provides numerous analysis options via seventeen control switches which give flexibility in performing the calculations best suited to the sample and the user needs. User input may be limited to the name of the library, the analysis livetime, and the spectrum filename and location. Output includes all peak analysis information, matrix correction factors, and element concentrations, uncertainties and detection limits. Twenty-four elements are typically determined from a 1024-channel spectrum in one-to-two minutes using a PDP-11/34 computer operating under RSX-11M.

  18. Americium characterization by X-ray fluorescence and absorption spectroscopy in plutonium uranium mixed oxide

    SciTech Connect (OSTI)

    Degueldre, Claude, E-mail: claude.degueldre@psi.ch; Cozzo, Cedric; Martin, Matthias; Grolimund, Daniel; Mieszczynski, Cyprian

    2013-06-01T23:59:59.000Z

    Plutonium uranium mixed oxide (MOX) fuels are currently used in nuclear reactors. The actinides in these fuels need to be analyzed after irradiation for assessing their behaviour with regard to their environment and the coolant. In this work the study of the atomic structure and next-neighbour environment of Am in the (Pu,U)O? lattice in an irradiated (60 MW d kg?¹) MOX sample was performed employing micro-X-ray fluorescence (µ-XRF) and micro-X-ray absorption fine structure (µ-XAFS) spectroscopy. The chemical bonds, valences and stoichiometry of Am (~0.66 wt%) are determined from the experimental data gained for the irradiated fuel material examined in its peripheral zone (rim) of the fuel. In the irradiated sample Am builds up as Am³? species within an [AmO?]¹³? coordination environment (e.g. >90%) and no (<10%) Am(IV) or (V) can be detected in the rim zone. The occurrence of americium dioxide is avoided by the redox buffering activity of the uranium dioxide matrix. - Graphical abstract: Americium LIII XAFS spectra recorded for the irradiated MOX sub-sample in the rim zone for a 300 ?m×300 ?m beam size area investigated over six scans of 4 h. The records remain constant during multi-scan. The analysis of the XAFS signal shows that Am is found as trivalent in the UO? matrix. This analytical work shall open the door of very challenging analysis (speciation of fission product and actinides) in irradiated nuclear fuels. - Highlights: • Americium was characterized by microX-ray absorption spectroscopy in irradiated MOX fuel. • The americium redox state as determined from XAS data of irradiated fuel material was Am(III). • In the sample, the Am³? face an AmO?¹³?coordination environment in the (Pu,U)O? matrix. • The americium dioxide is reduced by the uranium dioxide matrix.

  19. On the feasibility of using the intrinsic fluorescence of nucleotides for DNA sequencing.

    SciTech Connect (OSTI)

    Chowdhury, M. H.; Ray, K.; Johnson, R. L.; Gray, S. K.; Pond, J.; Lakowicz, J. R.; Univ. of Maryland; Univ. of Virginia; Lumerical Solutions, Inc.

    2010-04-29T23:59:59.000Z

    There is presently a worldwide effort to increase the speed and decrease the cost of DNA sequencing as exemplified by the goal of the National Human Genome Research Institute (NHGRI) to sequence a human genome for under $1000. Several high throughput technologies are under development. Among these, single strand sequencing using exonuclease appear very promising. However, this approach requires complete labeling of at least two bases at a time, with extrinsic high quantum yield probes. This is necessary because nucleotides absorb in the deep ultraviolet (UV) and emit with extremely low quantum yields. Hence intrinsic emission from DNA and nucleotides is not being exploited for DNA sequencing. In the present paper we consider the possibility of identifying single nucleotides using their intrinsic emission. We used the finite-difference time-domain (FDTD) method to calculate the effects of aluminum nanoparticles on nearby fluorophores that emit in the UV. We find that the radiated power of UV fluorophores is significantly increased when they are in close proximity to aluminum nanostructures. We show that there will be increased localized excitation near aluminum particles at wavelengths used to excite intrinsic nucleotide emission. Using FDTD simulation we show that a typical DNA base when coupled to appropriate aluminum nanostructures leads to highly directional emission. Additionally we present experimental results showing that a thin film of nucleotides show enhanced emission when in close proximity to aluminum nanostructures. Finally we provide Monte Carlo simulations that predict high levels of base calling accuracy for an assumed number of photons that is derived from the emission spectra of the intrinsic fluorescence of the bases. Our results suggest that single nucleotides can be detected and identified using aluminum nanostructures that enhance their intrinsic emission. This capability would be valuable for the ongoing efforts toward the $1000 genome.

  20. Engineering ESPT Pathways Based on Structural Analysis of LSSmKate Red Fluorescent Proteins with Large Stokes Shift

    SciTech Connect (OSTI)

    Piatkevich, K.; Malashkevich, V; Almo, S; Verkhusha, V

    2010-01-01T23:59:59.000Z

    LSSmKate1 and LSSmKate2 are monomeric red fluorescent proteins (RFPs) with large Stokes shifts (LSSs), which allows for efficient separation of absorbance and emission maxima, as well as for excitation with conventional two-photon laser sources. These LSSmKates differ by a single amino acid substitution at position 160 and exhibit absorbance maxima around 460 nm, corresponding to a neutral DsRed-like chromophore. However, excitation at 460 nm leads to fluorescence emission above 600 nm. Structures of LSSmKate1 and LSSmKate2, determined at resolutions of 2.0 and 1.5 {angstrom}, respectively, revealed that the predominant DsRed-chromophore configurations are cis for LSSmKate1 but trans for LSSmKate2. Crystallographic and mutagenesis analyses, as well as isotope and temperature dependences, suggest that an excited-state proton transfer (ESPT) is responsible for the LSSs observed in LSSmKates. Hydrogen bonding between the chromophore hydroxyl and Glu160 in LSSmKate1 and a proton relay involving the chromophore tyrosine hydroxyl, Ser158, and the Asp160 carboxylate in LSSmKate2 represent the putative ESPT pathways. Comparisons with mKeima LSS RFP suggest that similar proton relays could be engineered in other FPs. Accordingly, we mutated positions 158 and 160 in several conventional red-shifted FPs, including mNeptune, mCherry, mStrawberry, mOrange, and mKO, and the resulting FP variants exhibited LSS fluorescence emission in a wide range of wavelengths from 560 to 640 nm. These data suggest that different chromophores formed by distinct tripeptides in different environments can be rationally modified to yield RFPs with novel photochemical properties.