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Tables of Spectral-Line Intensities: Part 2 - Arranged by Wavelengths

Description: From Preface: "This new edition of the NBS Tables of Spectral-Line Intensities incorporates three improvements on the original edition of 1961. In the original edition only about 25 000 of the 39 000 lines in the tables had been classified. In the ensuing thirteen years, about 8500 more lines (chiefly rare-earths) have been classified and the new classifications are here incorporated."
Date: May 1975
Creator: Meggers, William F.; Corliss, Charles H. & Scribner, Bourdon F.
Partner: UNT Libraries Government Documents Department

Experimental Transition Probabilities for Spectral Lines of Seventy Elements: Derived from the NBS Tables of Spectral-line Intensities

Description: From introduction: "The goal of the work was to provide lists of the principal lines of the elements generally observed under ordinary conditions in arc spectra, together with their relative intensities on a true scale of relative energy."
Date: July 20, 1962
Creator: Corliss, Charles H. & Bozman, William R.
Partner: UNT Libraries Government Documents Department

Microwave Spectral Tables: [Volume 1.] Diatomic Molecules

Description: From Abstract: "For about 1500 spectral lines of diatomic molecules observed by coherent radiation techniques, measured frequencies, assigned quantum numbers, and newly computed intensities are given."
Date: December 1, 1964
Creator: Wacker, Paul F.; Mizushima, Masataka; Peterson, Jean D. & Ballard, Joe R.
Partner: UNT Libraries Government Documents Department

Microwave Spectral Tables: Volume 5. Spectral Line Listing

Description: From Abstract: "This volume is a listing of the spectral lines reported in Volume I, III, and IV of the Microwave Spectral Tables. These lines are listed according to ascending magnitude of frequency and should provide a steady reference."
Date: June 1968
Creator: Cord, Marian S.; Lojko, Matthew S. & Petersen, Jean D.
Partner: UNT Libraries Government Documents Department

Line Parameters and Computed Spectra for Water Vapor Bands at 2.7 mu

Description: From Foreword: "This Monograph is one of a series intended to provide fundamental information required for the estimation and interpretation of atmospheric transmittance at infrared frequencies. Part I of this Monograph presents the fundamental properties of the 2.7m water vapor band in terms of line absorptions and the integrated transmittance at any frequency for infinite resolution. Part II presents examples of the "degraded" transmittance for finite resolution, as a function of the spectral slit width, concentration, and pressure with which direct observations may be compared."
Date: August 3, 1964
Creator: Gates, David M.; Calfee, Robert F.; Hansen, David W. & Benedict, W. S.
Partner: UNT Libraries Government Documents Department

Tables of Spectral-Line Intensities: Part 1, Arranged by Elements

Description: Abstract: "These data are presented by element in part I, and all 39,000 observed lines are given in order of wavelength in Part II." From Introduction: "In the beginning, most intensity data were reported on an arbitrary scale of 10 steps, weak lines being assigned an intensity of 1, and the strongest line intensity 10."
Date: December 29, 1961
Creator: Meggers, William F.; Corliss, Charles H. & Scribner, Bourdon F.
Partner: UNT Libraries Government Documents Department

Tables of Spectral-Line Intensities: Part 1, Arranged by Elements

Description: From Abstract: "Comparisons with other other intensity measurements in individual spectra indicate that the National Bureau of Standards spectral-line intensities may have average errors of 20 percent, but first of all they provide uniform quantitative values for the seventy chemical elements commonly determined by spectrochemists. These data are presented by element in part I, and all 39000 observed lines are given in order of wavelength in part II."
Date: May 1975
Creator: Meggers, William F.; Corliss, Charles H. & Scribner, Bourdon F.
Partner: UNT Libraries Government Documents Department

Observed Differences in the Arc Spectra of U²³⁵ and U²³⁸

Description: Abstract: "It has been found that the two principal uranium isotopes exhibit slightly different arc spectra. Certain U-235 lines have been found to be displaced from corresponding U-238 lines by about one reciprocal centimeter. The intensity ratio, IU235/IU238, has been shown to be a steadily increasing function of the U-235 concentration. These data indicate the possibility of developing a method for the determination of isotopic concentration by means of emission spectra."
Date: January 15, 1947
Creator: Long, D. R. & Smith, D. D.
Partner: UNT Libraries Government Documents Department

The [beta]-Spectra of Pu²³⁹, Pu²⁴⁰, Pu²⁴¹and Sm¹⁵¹

Description: The [beta] spectrum of the 10-year Pu²⁴¹ was run on a sample of radiochemically pure plutonium containing the isotopes Pu²³⁹, Pu²⁴⁰, Pu²⁴¹, isotopically enriched in Pu²⁴¹ by pile neutron irradiation. The isotopic composition was determined mass spectrographically.
Date: February 8, 1952
Creator: Wagner, F.; Freedman, Melvin S. & Engelkemeir, D. W.
Partner: UNT Libraries Government Documents Department

Eckart frame motions and molecular vibrations

Description: This dissertation deals with motions of the Eckart frame in relation to molecular vibrations. The angular motion and the angular acceleration of the Eckart frame are treated. A technique for taking the first and second differentials of real symmetric eigenvalue problems is developed. This technique is applied to the first differential of the Eckart frame matrix.
Date: December 1978
Creator: Meyer, Frederick O.
Partner: UNT Libraries

The Spectrographic Determination of Iron in Uranium and Its Compounds

Description: Abstract: A spectrophotometric determination of iron employing the ferrous-1, 10-phenanthroline complex has been developed. The colored complex is measured at a wave-length where interference of the yellow uranyl ion is a minimum. Recommended procedures and analytical results using these procedures are given. Data are presented which indicate that the iron in the acid-insoluble residue is negligible. A method for the determination of iron in ammonium oxalate is included.
Date: July 1947
Creator: Fassel, Velmer A.; Tuthill, S. M. & Buckheim, O. J.
Partner: UNT Libraries Government Documents Department

Methods of Opacity Calculations

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

Photon Spectrum From Bremsstrahlung

Description: Abstract: The number of photons of given energy radiated in Bremsstrahlung collision of electrons with nuclei is calculated relativistically. Expansions are obtained for energies small to mc-squared. The photon spectrum is averaged over a Maxwell distribution for the electrons. Numerical results are included.
Date: August 11, 1953
Creator: Gluckstern, R. L.; Hull, M. H., Jr. & Breit, G.
Partner: UNT Libraries Government Documents Department

The Furnace Spectrum of Plutonium

Description: Abstract: "The spectrum of plutonium has been observed over the temperature range of 2000 to 2600 C and a wavelength coverage of 3476 to 6888 A. The spectrum was excited in a modified King furnace."
Date: May 12, 1953
Creator: Conway, John G.
Partner: UNT Libraries Government Documents Department

The Fission Neutron Spectrum of 25

Description: Abstract: "Photographic plates have been used to measure the energy of neutrons from the fission of 25. The spectrum as inferred from the ranges of 850 protons recoiling in the forward direction shows a very wide maximum at ~1.5 Mev with an exponentially decreasing high energy tail which extends beyond 7 Mev. The minimum energy neutrons recorded were ~700 kv. If the spectrum is extrapolated to zero, one finds that this average neutron energy is about 1.85 Mev. The stopping power of the plates was calibrated by the use of monochromatic neutrons from the Li-7(pn) Be-7 reaction and the d-d reaction."
Date: February 11, 1944
Creator: Richards, Hugh T. & Perlman, Isadore
Partner: UNT Libraries Government Documents Department