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Including Energy Efficiency and Renewable Energy Policies in Electricity Demand Projections

Description: A paper that has a methodology for estimating the energy impacts of key EE/RE on-the-books policies that are not explicitly reflected in the EIA's AEO 2013 electricity projections and including them in their baseline projections.
Date: April 2015
Creator: United States. Environmental Protection Agency.
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 Electron Emission Characteristics of Aluminum, Molybdenum and Carbon Nanotubes Studied by Field Emission and Photoemission.

Description: The electron emission characteristics of aluminum, molybdenum and carbon nanotubes were studied. The experiments were setup to study the emission behavior as a function of temperature and exposure to oxygen. Changes in the surface work function as a result of thermal annealing were monitored with low energy ultra-violet photoelectron spectroscopy for flat samples while field emission energy distributions were used on tip samples. The change in the field emission from fabricated single tips exposed to oxygen while in operation was measured using simultaneous Fowler-Nordheim plots and electron energy distributions. From the results a mechanism for the degradation in the emission was concluded. Thermal experiments on molybdenum and aluminum showed that these two materials can be reduced at elevated temperatures, while carbon nanotubes on the other hand show effects of oxidation. To purely reduce molybdenum a temperature in excess of 750 ºC is required. This temperature exceeds that allowed by current display device technology. Aluminum on the other hand shows reduction at a much lower temperature of at least 125 ºC; however, its extreme reactivity towards oxygen containing species produces re-oxidation. It is believed that this reduction is due to the outward diffusion of aluminum atoms through the oxide. Carbon nanotubes on the other hand show signs of oxidation as they are heated above 700 ºC. In this case the elevated temperatures cause the opening of the end caps allowing the uptake of water. Oxygen exposure experiments indicate that degradation in field emission is two-fold and is ultimately dependent on the emission current at which the tip is operated. At low emission currents the degradation is exclusively due to oxidation. At high emission currents ion bombardment results in the degradation of the emitter. In between the two extremes, molybdenum tips are capable of stable emission.
Date: December 2002
Creator: Sosa, Edward Delarosa
Partner: UNT Libraries

Weak Line Quasars at High Redshift: Extremely High Accretion Rates or Anemic Broad-Line Regions?

Description: This article presents Gemini-North K-band spectra of two representative members of the class of high-redshift quasars with exceptionally weak rest-frame ultraviolet emission lines.
Date: September 8, 2010
Creator: Shemmer, Ohad; Trakhtenbrot, Benny; Anderson, Scott F.; Brandt, William Nielsen; Diamond-Stanic, Aleksandar M.; Fan, Xiaohui et al.
Partner: UNT College of Arts and Sciences

A Population of X-Ray Weak Quasars: PHL 1811 Analogs at High Redshift

Description: This article reports the results from Chandra and XMM-Newton observations of a sample of 10 type 1 quasars selected to have unusual UV emission-line properties similar to those of PHL 1811.
Date: April 15, 2011
Creator: Wu, Jianfeng; Brandt, William Nielsen; Hall, Patrick B.; Gibson, Robert R.; Richards, Gordon T.; Schneider, Donald P. et al.
Partner: UNT College of Arts and Sciences

The Ultraviolet-To-Mid-Infrared Spectral Energy Distribution of Weak Emission Line Quasars

Description: This article presents Spitzer Space Telescope photometry of 18 Sloan Digital Sky Survey quasars which have weak or undetectable high-ionization emission lines in their rest-frame ultraviolet spectra.
Date: September 23, 2011
Creator: Lane, Ryan A.; Shemmer, Ohad; Diamond-Stanic, Aleksandar M.; Fan, Xiaohui; Anderson, Scott F.; Brandt, William Nielsen et al.
Partner: UNT College of Arts and Sciences

A Statistical Relation Between the X-ray Spectral Index and Eddington Ratio of Active Galactic Nuclei in Deep Surveys

Description: This article presents an investigation into how well the properties of the accretion flow on to a supermassive black hole may be coupled to those of the overlying hot corona.
Date: May 22, 2013
Creator: Brightman, M.; Silverman, John David; Mainieri, Vincenzo; Ueda, Yoshihiro; Schramm, Malte; Matsuoka, Kenta et al.
Partner: UNT College of Arts and Sciences

High-Redshift SDSS Quasars With Weak Emission Lines

Description: This article identifies a sample of 74 high-redshift quasars with weak emission lines from the Fifth Data Release of the Sloan Digital Sky Survey and present infrared, optical, and radio observations of a subsample of four objects at z > 4.
Date: April 16, 2009
Creator: Diamond-Stanic, Aleksandar M.; Fan, Xiaohui; Brandt, William Nielsen; Shemmer, Ohad; Strauss, Michael A.; Anderson, Scott F. et al.
Partner: UNT College of Arts and Sciences

The Hard X-Ray Spectrum as a Probe for Black Hole Growth in Radio-Quiet Active Galactic Nuclei

Description: This article studies the hard X-ray spectral properties of 10 highly luminous radio-quiet active galactic nuclei at z = 1.3-3.2, including new XMM-Newton observations of four of these sources.
Date: April 3, 2008
Creator: Shemmer, Ohad; Brandt, William Nielsen; Netzer, Hagai; Maiolino, Roberto & Kaspi, Shai
Partner: UNT College of Arts and Sciences

Air Emission Inventory for the INEEL -- 1999 Emission Report

Description: This report presents the 1999 calendar year update of the Air Emission Inventory for the Idaho National Engineering and Environmental Laboratory (INEEL). The INEEL Air Emission Inventory documents sources and emissions of nonradionuclide pollutants from operations at the INEEL. The report describes the emission inventory process and all of the sources at the INEEL, and provides nonradionuclide emissions estimates for stationary sources.
Date: May 1, 2000
Creator: Zohner, Steven K
Partner: UNT Libraries Government Documents Department