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The Addition of a Second Lanthanide Ion to Increase the Luminescence of Europium(III) Macrocyclic Complexes

Description: At present, the microscopic visualization of luminescent labels containing lanthanide(III) ions, primarily europium(III), as light-emitting centers is best performed with time-gated instrumentation, which by virtually eliminating the background fluorescence results in an improved signal to noise ratio. However, the use of the europium(III) macrocycle, Quantum Dye{trademark}, in conjunction with the strong luminescence enhancing effect (cofluorescence) of yttrium(III) or gadolinium(III), can eli… more
Date: December 29, 1998
Creator: Bromm, Alfred J. Jr.; Vallarino, L.M.; Leif, Robert C. & Quagliano, John R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Multi-Window Classical Least Squares Multivariate Calibration Methods for Quantitative ICP-AES Analyses

Description: The advent of inductively coupled plasma-atomic emission spectrometers (ICP-AES) equipped with charge-coupled-device (CCD) detector arrays allows the application of multivariate calibration methods to the quantitative analysis of spectral data. We have applied classical least squares (CLS) methods to the analysis of a variety of samples containing up to 12 elements plus an internal standard. The elements included in the calibration models were Ag, Al, As, Au, Cd, Cr, Cu, Fe, Ni, Pb, Pd, and Se.… more
Date: October 1999
Creator: Chambers, William B.; Haaland, David M.; Keenan, Michael R. & Melgaard, David K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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New liquid scintillators for fiber-optic applications

Description: New long-wavelength-emitting, high-speed, liquid scintillators have been developed and tailored specifically for plasma diagnostic experiments employing fiber optics. These scintillators offer significant advantages over commercially available plastic scintillators in terms of sensitivity and bandwidth. FWHM response times as fast as 350 ps have been measured. Emission spectra, time response data, and relative sensitivity information are presented.
Date: January 1, 1981
Creator: Lutz, S. S.; Franks, L. A.; Flournoy, J. M. & Lyons, P. B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Highly Luminescent Lanthanide Complexes of 1 Hydroxy-2-pyridinones

Description: The synthesis, X-ray structure, stability, and photophysical properties of several trivalent lanthanide complexes formed from two differing bis-bidentate ligands incorporating either alkyl or alkyl ether linkages and featuring the 1-hydroxy-2-pyridinone (1,2-HOPO) chelate group in complex with Eu(III), Sm(III) and Gd(III) are reported. The Eu(III) complexes are among some of the best examples, pairing highly efficient emission ({Phi}{sub tot}{sup Eu} {approx} 21.5%) with high stability (pEu {ap… more
Date: November 1, 2007
Creator: University of California, Berkeley; Laboratory, Lawrence National; Raymond, Kenneth; Moore, Evan G.; Xu, Jide; Jocher, Christoph J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Imaging x-ray spectrometer to study solar activity in conjunction with the SCADM program

Description: An experiment is proposed to study solar active region dynamics and evolution. It will greatly extend the range of capabilities provided by the Solar Maximum Mission. The larger volume and weight capacity of a shuttle launch make possible an experiment with enough sensitivity to study the fastest known solar phenomena with high spatial and spectral resolution. It will be possible to use high spectral resolving power to image events on a small scale in short time intervals, and it will be possib… more
Date: January 1, 1979
Creator: Blake, R.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Chemometric analysis of infrared emission spectra for quantitative analysis of BPSG films on silicon

Description: Infrared emission spectra of 21 borophosphosilicate glass (BPSG) thin films on silicon wafers were collected with the samples held at constant temperature between 125--400{degree}C using a heating stage designed for precise temperature control ({plus_minus}{degree}C). Partial test squares calibrations applied to the BPSG infrared emittance spectra allowed four BPSG thin-film properties to be simultaneously quantified with precisions of 0.1 wt. % for boron and phosphorus, 35 {Angstrom} for film … more
Date: November 1, 1993
Creator: Franke, J. E.; Chen, Chuenyuan S.; Zhang, Songbaio; Niemczyk, T. M. & Haaland, D. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Characterization of short pulse laser-produced plasmas at the Lawrence Livermore National Laboratory ultra short-pulse laser

Description: The K-shell emission from porous aluminum targets is used to infer the density and temperature of plasmas created with 800 nm and 400 nm, 140 fs laser light. The laser beam is focused to a minimum spot size of 5 {mu}m with 800 nm light and 3 {mu}m with 400 nm light, producing a normal incidence peak intensity of 10{sup 18} Watts/cm{sup 2}. A new 800 fs x-ray streak camera is used to study the broadband x-ray emission. The time resolved and time integrated x-ray emission implies substantial diff… more
Date: July 14, 1993
Creator: Shepherd, R.; Price, D.; White, W.; Osterheld, A.; Walling, R.; Goldstein, W. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Configuration interaction in LTE spectra of heavy elements

Description: We present a method for including the effects of configuration interaction (CI) between relativistic subconfigurations of an electron configuration in the calculation of emission and absorption spectra of plasmas in local thermodynamic equilibrium (LTE). Analytical expressions for the correction to the intensities, owing to Cl, of an unresolved transition array (UTA) and of a supertransition array (STA) are obtained when the correction is small compared to the spin-orbit splitting, bypassing th… more
Date: November 1, 1992
Creator: Bar-Shalom, A.; Oreg, J. & Goldstein, W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Spectroscopy and dynamics of 5f states of Es{sup 3+} in LaF{sub 3}

Description: Using time- and wavelength-resolved laser-induced fluorescence methods, the 5f state spectroscopy and photodynamics of {sup 253}Es{sup 3+} in LaF{sub 3} have been investigated. Based on an effective operator Hamiltonian model and approximating the metal ion site symmetry as C{sub 2V}, a set of crystal field parameters has been obtained that fit the 56 assigned levels associated with the 7 states of Es{sup 3+} that were observed. The {sup 5}F{sub 5} emitting state of Es{sup 3+} exhibited a decay… more
Date: November 1, 1997
Creator: Beitz, J.V.; Williams, C.W. & Liu, G.K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Wire array z-pinch insights for high X-ray power generation

Description: The discovery that the use of very large numbers of wires enables high x-ray power to be generated from wire-array z-pinches represents a breakthrough in load design for large pulsed power generators, and has permitted high temperatures to be generated in radiation cavities on Saturn and Z. In this paper, changes in x-ray emission characteristics as a function of wire number, array mass, and load radius, for 20-mm-long aluminum arrays on Saturn that led to these breakthrough hohlraum results, a… more
Date: 1998
Creator: Sanford, T. W. L.; Marder, B. M. & Desjarlais, M. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Laser demonstrations of rare-earth ions in low-phonon chloride and sulfide crystals

Description: Laser results are summarized for the low-phonon hosts KPb{sub 2}Cl{sub 5} and CaGa{sub 2}S{sub 4}. Radiative quantum efficiencies were determined in KPb{sub 2}Cl{sub 5}:Dy{sup 3+} directly from emission spectra in order to accurately determine its long-wavelength potential. The results indicate that room-temperature laser action should be possible to near 9 {micro}m in this host.
Date: April 1, 2000
Creator: Nostrand, M; Page, R; Payne, S; Schunemann, P & Isaenko, L
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Iterative retrieval of surface emissivity and temperature for a hyperspectral sensor

Description: The central problem of temperature-emissivity separation is that we obtain N spectral measurements of radiance and need to find N + 1 unknowns (N emissivities and one temperature). To solve this problem in the presence of the atmosphere we need to find even more unknowns: N spectral transmissions {tau}{sub atmo}({lambda}) up-welling path radiances L{sub path}{up_arrow}({lambda}) and N down-welling path radiances L{sub path}{down_arrow}({lambda}). Fortunately there are radiative transfer codes s… more
Date: November 1, 1997
Creator: Borel, C.C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Time-Resolved Temperatures of Shocked and Detonating Energetic Materials

Description: Chemical processes occurring in shock-compressed and detonating high explosives have been studied using fast time-resolved emission spectroscopy and a two-stage gas-gun. The spectral characteristics of emission from shock-compressed nitromethane, tetranitromethane and single crystals of pentaerythritol tetranitrate are typically very broad and structureless, likely representing thermal emission. Assuming the thermal emission from a gray-body, the emission intensity can be correlated to the temp… more
Date: August 14, 1995
Creator: Yoo, C. S.; Holmes, N. C. & Souers, P. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Benchmark Measurements of the Ionization Balance of Non-LTE Gold

Description: The authors present a series of benchmark measurements of the ionization balance of well characterized gold plasmas with and without external radiation fields at electron densities near 10{sup 21} cm{sup -3} and various electron temperatures spanning the range 0.8 to 2.4 keV. They have analyzed time- and space-resolved M-shell gold emission spectra using a sophisticated collisional-radiative model with hybrid level structure, finding average ion changes <Z> ranging from 42 to 50. At the l… more
Date: April 20, 2007
Creator: Heeter, R. F.; Hansen, S. B.; Fournier, K. B.; Foord, M. E.; Froula, D. H.; Mackinnon, A. J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Time-dependent multi-dimensional simulation studies of the electron output scheme for high power FELs

Description: The authors examine the performance of the so-called electron output scheme recently proposed by the Novosibirsk group. In this scheme, the key role of the FEL oscillator is to induce bunching, while an external undulator, called the radiator, then outcouples the bunched electron beam to optical energy via coherent emission. The level of the intracavity power in the oscillator is kept low by employing a transverse optical klystron (TOK) configuration, thus avoiding excessive thermal loading on … more
Date: December 1, 1994
Creator: Hahn, S. J.; Fawley, W. M.; Kim, K. J. & Edighoffer, J. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A photoemission study of Au, Ge, and O{sub 2} deposition on NH{sub 4}F etched Si(111)

Description: We have studied the interaction of a metal, Au, a semiconductor, Ge, and a non-metal, O{sub 2}, with the NH{sub 4}F etched Si(111) surface with photoemission spectroscopy. Two components were present in Si 2p core level spectra from the H-terminated surface. We observed the flat band condition from the as-etched, n-type, Si(111) surface. We performed stepwise depositions of Au and measured the band bending with photoemission spectroscopy. The Fermi level pinned near mid-gap as Au was deposited … more
Date: March 1, 1994
Creator: Terry, J.; Cao, R.; Wigren, C. & Pianetta, P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Spectrally and temporally resolved laser emission from vertical cavity surface emitting lasers

Description: We have measured the laser emission spectra of several vertical cavity surface emitting lasers following pulsed laser excitation, with a time resolution of < 1 ps. Correlations between the observed pulse widths and cavity lifetimes were observed.
Date: December 31, 1992
Creator: Sinclair, M.; Gourley, P. L.; Brennan, T. M. & Hammons, B. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Infrared and visible laser double resonance studies of vibrational energy transfer processes in polyatomic molecules. Final report, June 15, 1988--June 14, 1991

Description: A study of the spectroscopy of chromyl chloride (CrO{sub 2}Cl{sub 2}?) in dilute solutions has been initiated. A discussion is given of its spectra and emission bands. 17 refs, 5 figs, 1 tab. (DLC)
Date: December 31, 1991
Creator: Bhatnagar, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Development of Layered Photonic Band Gap Structures Using a Micro-Transfer Molding Technique

Description: Photonic band gap (PBG) crystals are periodic dielectric structures that manipulate electromagnetic radiation in a manner similar to semiconductor devices manipulating electrons. Whereas a semiconductor material exhibits an electronic band gap in which electrons cannot exist, similarly, a photonic crystal containing a photonic band gap does not allow the propagation of specific frequencies of electromagnetic radiation. This phenomenon results from the destructive Bragg diffraction interference … more
Date: May 1, 2001
Creator: Sutherland, Kevin Jerome
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Generation of x-ray pulses with rapid rise times to pump inner-shell photo-ionized x-ray lasing in carbon at 45 {angstrom}

Description: An investigation of the rapid rise time of x-ray emission from targets heated by an ultrashort-pulse high-intensity optical laser was conducted for use as a pump for inner-shell photo-ionized x-ray lasing. Results of x-ray rise times from instantaneously heated Au rod targets show little benefit for using optical pulse widths less than 30 fs. Gain calculations for inner-shell photo-ionized lasing show that large gains can be obtained for pulse widths between 30 and 100 fs. Calculated spectra, u… more
Date: July 28, 1995
Creator: Moon, S. J. & Eder, D. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Using spectral line profiles as a diagnostic of the plasma electron density

Description: A description of a simple interactive fitting procedure is given which uses line profiles calculated for highly stripped ions, i.e., hydrogenic, helium-like and lithium-like species. Information on the calculation of these profiles is provided. The experimental data is read from disk, so any appropriately formatted data can be referenced.
Date: August 1, 1981
Creator: Lee, R.W. & Matthews, D.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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