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Thermonuclear Project Semiannual Progress Report: for Period Ending July 31, 1960

Description: From Introduction: "The present semiannual progress report introduces more active consideration than has been given in the past (by us, at least) to the importance of energy degradation in DCX-like devices. The following pages introduce also a new major apparatus designated as DCX-2. Some of these concepts cannot as yet be released publicly and therefore Chap. 3 of this report, covering the DCX-EP-B design, is being issued separately, with restricted distribution, as ORNL-3044."
Date: January 13, 1961
Partner: UNT Libraries Government Documents Department

Spectroscopy of Uranyl Salts in the Solid State

Description: From Introduction: "The interpretation of the fluorescence and absorption spectrum of the uranyl ion, indicated in this introduction, is based on the spectroscopic work of Nichols, Howes and co-workers (1914-1919), Dieke and van Heel (1925), Moerman and Kraak (1939), and Freymann and co-workers (1946-1948); on infrared studies (cf., Section 3 below) and Raman spectra; but most of all, on the work of Dieke, Duncan, and co-workers, carried out in 1943-1944 under the Manhattan District program. In the present chapter we will review briefly the earlier investigations in the field of uranyl salt and spectroscopy and give a somewhat more detailed summary of the results of Nichols and Howes and, particularly, of Dieke and co-workers."
Date: November 1953
Creator: Rabinowitch, Eugene
Partner: UNT Libraries Government Documents Department

Effect of Mn Substitution for Multiferroic BiFeO3 Probed by High-Resolution Soft-X-Ray Spectroscopy

Description: The electronic structures of BiFeO{sub 3} (BF) and Mn-doped BiFeO{sub 3} (BF(Mn)) have been studied by X-ray absorption spectroscopy (XAS) and soft-X-ray emission spectroscopy (SXES). The BF and BF(Mn) have the mixed valence state of Fe{sup 2+} and Fe{sup 3+}. The valence band is mainly composed of O 2p state hybridized with the majority-spin t{sub 2g} and e{sub g} orbitals of Fe 3d state. The conduction band is composed of the minority-spin t{sub 2g} and e{sub g} orbitals of Fe 3d. The band gaps of BF and BF(Mn) are estimated to be 1.3 eV and 2.7 eV, respectively. The increase of band gap with Mn substitution contributes to the change of bandwidth of valence band.
Date: July 11, 2008
Creator: Higuchi, Tohru; Higuchi, T.; Hattori, T.; Sakamoto, W.; Itoh, N.; Shimura, T. et al.
Partner: UNT Libraries Government Documents Department

Hierarchy of multiple many-body interaction scales in high-temperature superconductors

Description: To date, angle-resolved photoemission spectroscopy has been successful in identifying energy scales of the many-body interactions in correlated materials, focused on binding energies of up to a few hundred meV below the Fermi energy. Here, at higher energy scale, we present improved experimental data from four families of high-T{sub c} superconductors over a wide doping range that reveal a hierarchy of many-body interaction scales focused on: the low energy anomaly ('kink') of 0.03-0.09eV, a high energy anomaly of 0.3-0.5eV, and an anomalous enhancement of the width of the LDA-based CuO{sub 2} band extending to energies of {approx} 2 eV. Besides their universal behavior over the families, we find that all of these three dispersion anomalies also show clear doping dependence over the doping range presented.
Date: December 21, 2006
Creator: Hussain, Zahid; Meevasana, W.; Zhou, X.J.; Sahrakorpi, S.; Lee, W.S.; Yang, W.L. et al.
Partner: UNT Libraries Government Documents Department

Polycyclic Aromatic Hydrocarbon Solute Probes. Part 5: Fluorescence Spectra of Pyrene, Ovalene, Coronene, and Benzo[ghi]perylene Dissolved in Liquid Alkylammonium Thiocyanate Organic Salts

Description: Article on polycyclic aromatic hydrocarbon solute probes and fluorescence spectra of pyrene, ovalene, coronene, and benzo[ghi]perylene dissolved in liquid alkylammonium thiocyanate organic salts.
Date: February 24, 1989
Creator: Street, Kenneth W.; Acree, William E. (William Eugene); Fetzer, John Charles, 1953-; Shetty, Prabhakara H. & Poole, Colin F.
Partner: UNT College of Arts and Sciences

The Development and Application of Capillary Absorption Cells

Description: Abstract: "Various types of capillary absorption cells have been constructed from a variety of materials. These cells, having volumes as low as 160 microliters, have been used to increase the sensitivity of several colorimetrics methods as much as 1000 fold without appreciable loss of accuracy. Small volumes of solution must be used in order to concentrate the colored material present."
Date: 1951
Creator: Rosenfels, R. S.; Kirk, P. L.; Kitson, R. E.; Patton, R. L. & Curtis, R. E.
Partner: UNT Libraries Government Documents Department

Soft X-Ray and Vacuum Ultraviolet Based Spectroscopy of the Actinides

Description: The subjects of discussion included: VUV photoelectron spectroscopy, X-ray photoelectron spectroscopy, Synchrotron-radiation-based photoelectron spectroscopy, Soft x-ray absorption spectroscopy, Soft x-ray emission spectroscopy, Inverse photoelectron spectroscopy, Bremstrahlung Isochromat Spectroscopy, Low energy IPES, Resonant inverse photoelectron spectroscopy.
Date: March 17, 2011
Creator: Tobin, J. G.
Partner: UNT Libraries Government Documents Department

2011 GASEOUS IONS GORDON RESEARCH CONFERENCE

Description: The Gaseous Ions: Structures, Energetics and Reactions Gordon Research Conference will focus on ions and their interactions with molecules, surfaces, electrons, and light. The conference will cover theory and experiments, and systems ranging from molecular to biological to clusters to materials. The meeting goal continues to be bringing together scientists interested in fundamentals, with those applying fundamental phenomena to a wide range of practical problems. Each of the ten conference sessions will focus on a topic within this spectrum, and there will also be poster sessions for contributed papers, with sufficient space and time to allow all participants to present their latest results. To encourage active participation by young investigators, about ten of the poster abstracts will be selected for 15 minute 'hot topic' talks during the conference sessions. Hot topic selection will be done about a month before the meeting. Funds should be available to offset the participation cost for young investigators.
Date: March 4, 2011
Creator: Anderson, Scott
Partner: UNT Libraries Government Documents Department

Radioactivity of Potassium Solutions: A Comparison of Calculated Activity to Measured Activity from Gross Beta Counting and Gamma Spectroscopy

Description: In order to determine if the measured beta activity for a solution containing potassium was exactly as predicted, particularly since the CES gas counter is not calibrated specifically with K-40, an experiment was conducted to compare measured activities from two radioanalytical methods (gamma spectroscopy and gas proportional counting) to calculated activities across a range of potassium concentrations. Potassium, being ubiquitous and naturally radioactive, is a well-known and common interference in gross beta counting methods. By measuring the observed beta activity due to K-40 in potassium-containing solutions across a wide range of concentrations, it was found that the observed beta activity agrees well with the beta activity calculated from the potassium concentration measured by standard inorganic analytical techniques, such as ICP-OES, and that using the measured potassium concentration to calculate the expected beta activity, and comparing this to the observed beta activity to determine if potassium can account for all the observed activity in a sample, is a valid technique. It was also observed that gamma spectroscopy is not an effective means of measuring K-40 activity below approximately 700 pCi/L, which corresponds to a solution with approximately 833 mg/L total potassium. Gas proportional counting for gross beta activity has a much lower detection limit, typically 20-50 picoCi/L for a liquid low in total dissolved solids, which corresponds to a potassium concentration of approximately 30-70 ppm K.
Date: July 26, 2005
Creator: Gaylord, R F
Partner: UNT Libraries Government Documents Department

Electronic Structure of the ID Conductor K0.3MoO3 studied using resonant inelastic x-ray scattering and soft x-ray emission spectroscopy

Description: The electronic structure of the quasi-one dimensional conductor K{sub 0.3}MoO{sub 3} has been measured using high resolution resonant inelastic x-ray scattering and x-ray absorption spectroscopy. The data is compared to that from the related two dimensional insulator {alpha}-MoO{sub 3}. Scattering features are observed from both oxides that are explained in terms of the band momentum selectivity of the scattering process, allowing a comparison of the scattering data to recent band structure calculations.
Date: September 24, 2008
Creator: Learmonth, T.; Glans, P.-A.; McGuinness, C.; Plucinski, L.; Zhang, Y.; Guo, J.-H. et al.
Partner: UNT Libraries Government Documents Department

Microwave Line Widths of the Asymmetric Top Formic Acid Molecule

Description: This work consisted of an experimental investigation of the formic acid (HCOOH) molecule's rotational spectrum. Measurements of line widths were obtained for J = 5, 12, 13, 19, and 20 for a pressure range from 1 to 10 microns. A linear behavior between Av and p was observed as predicted by theory. The line width parameter Avp was observed to depend on the quantum number J. Hard sphere collision diameters b1 were calculated using the obtained AvP values. These deduced hard sphere values were found to be larger than the physical size of the molecule. This result was found to be in general agreement with other investigation in which long range forces (dipole-dipole) dominate.
Date: August 1974
Creator: Maynard, Wayne R.
Partner: UNT Libraries

Light hadron spectroscopy

Description: I review the progress that has been made in light hadron spectroscopy from lattice QCD, since the LATTICE`94 conference in Bielefeld.
Date: December 31, 1995
Creator: Sinclair, D.K.
Partner: UNT Libraries Government Documents Department