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Trajectory versus probability density entropy

Description: In this article, the authors show that the widely accepted conviction that a connection can be established between the probability density entropy and the Kolmogorov-Sinai (KS) entropy is questionable.
Date: 2001
Creator: Bologna, Mauro; Grigolini, Paolo; Karagiorgis, Markos & Rosa, Angelo
Partner: UNT College of Arts and Sciences

Generalization of gas-flow-interferometry theory and interferogram evaluation equations for one-dimensional density fields

Description: Report presenting interferogram equations for calculating one-dimensional density distributions from optical-interference records, which are derived from generalized equations. The resulting evaluation equations are applicable for any plane of focus.
Date: February 1955
Creator: Howes, Walton L. & Buchele, Donald R.
Partner: UNT Libraries Government Documents Department

Density profiles of subsonic boundary layers on a flat plate determined by x-ray and pressure measurements

Description: Report presenting an investigation of laminar, transitional, and turbulent boundary layers in a subsonic wind tunnel at two Mach numbers at various Reynolds numbers and stations along a flat plate. Comparisons are made of the density profiles obtained with a total-pressure probe of small frontal opening and by means of an X-ray absorption method and, in a few cases, by using interferometer data.
Date: February 1954
Creator: Weltmann, Ruth N. & Kuhns, Perry W.
Partner: UNT Libraries Government Documents Department

Surface Dependent Electron and Negative Ion Density in Inductively Coupled Discharges

Description: Electron and negative ion density have been measured in a modfied Applied Materials DPS metal etch chamber using gas mixtures of BCl{sub 3}, Cl{sub 2} and Ar. Measurements were performed for four dflerent substrate types to examine the influence of surface material on the bulk plasma properties; aluminurq alumina, photoresist and 50 percent patterned aluminum / photoresist. Electron densities in the Cl{sub 2} / BCl{sub 3} mixtures varied from 0.25 to 4 x 10{sup 11} cm{sup -3}. Photodetachment measurements of the negative ion density indicate that the negative ion density was smaller than the electron density and that the electron to negative ion density ratio varied between 1 and 6. The presence of photoresist had a dominant intluence on the electron and negative ion density compared to alumina and aluminum surfaces. In most cases, the electron density above wafers covered with photoresist was a factor of two lower while the negative ion density was a factor of two higher than the aluminum or alumina surfaces.
Date: January 18, 1999
Creator: Blain, M.G.; Hamilton, T.W.; Hebner, G.A.; Jarecki, R.L. & Nichols, C.A.
Partner: UNT Libraries Government Documents Department

Thermochemical and Theoretical Studies of Dimethylpyridine-2,6-dicarboxylate and Pyridine-2,3-, Pyridine-2,5-, and Pyridine-2,6-dicarboxylic Acids

Description: Article discussing thermochemical and theoretical studies of dimethylpyridine-2,6-dicarboxylate and pyridine-2,3-, pyridine-2,5- and pyridine-2,6-dicarboxylic acids.
Date: May 6, 2005
Creator: Matos, M. Agostinha R.; Morais, Victor M. F.; Silva, Maria D. M. C. Ribeiro da; Marques, Marta C. F.; Sousa, Emanuel A.; Castiñeiras, Jorge P. et al.
Partner: UNT College of Arts and Sciences

Some measurements of atmosphere turbulence obtained from flow-direction vanes mounted on an airplane

Description: Report presenting a calculation of the power spectrum of relatively short wavelength turbulence in the atmosphere using measurements made in flight. The power spectral density varies with the square of the wavelength of the turbulence. Results regarding the power spectrum of gust vertical velocity, problems related to gust disturbance determination, and use of flow-direction vanes are provided.
Date: November 1954
Creator: Chilton, Robert G.
Partner: UNT Libraries Government Documents Department

Electronic Structure of zinc-blende AlxGa1-xN; Screened-ExchangeStudy

Description: We present a first principle investigation of the electronicstructure and the band gap bowing parameter of zinc-blende \AlGaN usingboth local density approximation and screened-exchange density functionalmethod. The calculated sX-LDA band gaps for GaN and AlN are 95 percentand 90 percent of the experimentally observed values, respectively, whileLDA under estimates the gaps to 62 percent and 70 percent. In contrast tothe gap itself, the band gap bowing parameter is found to be very similarin sX-LDA and LDA. Because of the difference in the conduction bandstructure, the direct to indirect band gap crossover is predicted tooccur at different Al concentration.
Date: January 3, 2006
Creator: Lee, Byounghak & Wang, Lin-Wang
Partner: UNT Libraries Government Documents Department

Experimental and model-based study of the robustness of line-edgeroughness metric extraction in the presence of noise

Description: As critical dimensions shrink, line edge and width roughness (LER and LWR) become of increasing concern. Crucial to the goal of reducing LER is its accurate characterization. LER has traditionally been represented as a single rms value. More recently the use of power spectral density (PSD), height-height correlation (HHCF), and {sigma} versus length plots has been proposed in order to extract the additional spatial descriptors of correlation length and roughness exponent. Here we perform a modeling-based noise-sensitivity study on the extraction of spatial descriptors from line-edge data as well as an experimental study of the robustness of these various descriptors using a large dataset of recent extreme-ultraviolet exposure data. The results show that in the presence of noise and in the large dataset limit, the PSD method provides higher accuracy in the extraction of the roughness exponent, whereas the HHCF method provides higher accuracy for the correlation length. On the other hand, when considering precision, the HHCF method is superior for both metrics.
Date: June 1, 2007
Creator: Naulleau, Patrick P. & Cain, Jason P.
Partner: UNT Libraries Government Documents Department

Interfacial structures and energetics of the strengthening precipitate phase in creep-resistant Mg-Nd-based alloys

Description: This article discusses the study of two interfaces– {112}β1/{1100}Mg and {111}β1/{1120}Mg– that are commensurate with β1/hcp-Mg orientation relationship via first principles calculations.
Date: January 17, 2017
Creator: Choudhuri, Deep; Banerjee, Rajarshi & Srivilliputhur, Srinivasan
Partner: UNT College of Engineering

Particle-In-Cell/Monte Carlo Simulation of Ion Back Bombardment in Photoinjectors

Description: In this paper, we report on studies of ion back bombardment in high average current dc and rf photoinjectors using a particle-in-cell/Monte Carlo method. Using H{sub 2} ion as an example, we observed that the ion density and energy deposition on the photocathode in rf guns are order of magnitude lower than that in a dc gun. A higher rf frequency helps mitigate the ion back bombardment of the cathode in rf guns.
Date: March 2, 2009
Creator: Qiang, Ji; Corlett, John & Staples, John
Partner: UNT Libraries Government Documents Department

PROGRESS RELATING TO CIVILIAN APPLICATIONS DURING NOVEMBER 1958

Description: The effect of irradiation on the thermal conductivity and electrical resistivity of U and U0/sub 2/ is being investigated. The creep properties of 15% cold-worked Zircaloy-2 are being investigated in the 290 to 400 deg C temperature range for times exceeding 10,000 hr. The density distribution of crushed graphite is being investigated by the sink-float method. Centrifugal- casting techniques for the production of Al-35 wt.% U casting in the form of hollow cylinders are being investigated. A study of the processes involved in the solidification of U castings in graphite molds is being made. Work continued on electrolytic oxide and electroless oxide coatings on Croloy-2 1/4. Experimental work was continued to determine the effect of additive oxides on the oxidation characteristics and phase stability of U0/sub 2/. The fueled-moderator study has continued with the determination of additional hydrogen-absorption isotherms for the Zr-25 wt.% alloy and high-temperature x-ray diffraction patterns of hydrides of the 1 and 50 wt.% alloys. The irradiation of type 347 stainless steel at ETR process-water temperature. about 120 deg F and at 600 deg F, and subsequent determination of irradiation damage are being done in support of the KAPL-33 loop to be installed at the ETR. AIloys of U and Nb are being considered as possible high-temperature reactor fuels. Thorium-uranium base alloys are the subject of an investigation aimed at improving irradiation stability and corrosion resistance by ternary alloying and control of processing techniques Cermet fuel materials consisting of from 60 to 90 vol.% U0/sub 2/, UN, or UC dispersed in stainless steel are being investigated. Several types of 1 1/ 2-inch-diameter fueled graphite spheres containing 10 wt.% of fully enriched U0/ sub 2/ are being evaluated before and after irradiation in the BRR. Some localized attack has been observed after prolonged exposure of Ti steam tubes ...
Date: December 1, 1958
Creator: Dayton, R.W. & Tipton, C.R. Jr.
Partner: UNT Libraries Government Documents Department