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Mechanical Behavior of Crystalline Solids: Proceedings of a Symposium, April 28-29, 1962

Description: From Introduction: "These first three chapters from a background of introduction and general ideas about dislocations. The next two chapters are concerned specifically with properties of ceramic materials, with emphasis on single crystals."
Date: March 25, 1963
Creator: United States. Bureau of Standards.
Partner: UNT Libraries Government Documents Department

[Red Crystal]

Description: Photograph of a circular red crystal set against a black background. The crystal has a multitude of colors within it, and the image was signed by Junebug Clark along the lower rim.
Date: 19uu
Creator: Clark, Joseph Wade Junebug & Clark, Joe
Partner: UNT Libraries Special Collections

Effective dielectric constants of photonic crystal of aligned anisotropic cylinders and the optical response of a periodic array of carbon nanotubes

Description: This article discusses effective dielectric constants of photonic crystal of aligned anisotropic cylanders and the optical response of a periodic array of carbon nanotubes.
Date: October 25, 2005
Creator: Reyes, E.; Krokhin, Arkadii A. & Roberts, James A.
Partner: UNT College of Arts and Sciences

The Bragg Reflection of Neutrons by a Single Crystal

Description: From cover page: This document has been assigned the above MDDC (Manhattan District Declassification) number, as given in the List of Declassified Documents issued semi-monthly by the Research Division, Manhattan District. In the case of Los Alapnos reports, LADC (Los Alamos Declassification) numbers are listed on the title page if known. This declassified document may differ materially from the original classified document by reason of deletions necessary to accomplish declassification. Hence, this copy of a declassified document does not constitute authority for declassification of classified copies of a similar document which may bear the same title and authors. Reference is made to District Circular Letter (Research Control 47-3) dated 31 October 1946, subject: "Instructions for Use of List of Declassified Documents," which outlines the procedure by means of which declassification of classified copies may be effected. Every effort has been made to reproduce with accuracy of detail the declassified document as certified for declassification. No corrections or changes have been made in the content of the document.
Date: June 14, 1946
Creator: Zinn, Walter H.
Partner: UNT Libraries Government Documents Department

Progress Report on AEC Contract on Research and Development Program on Scintillation Crystals: Period 1 January 1956 to 1 April 1956

Description: From Abstract: "This report covers the preliminary literature survey and the screening of activated cesium iodide and several alkali halides to qualitatively determine their luminerscence. The report also includes a proposal of the future work and a proposed budget for the 1957 fiscal year."
Date: April 25, 1956
Creator: Beadle, Robert
Partner: UNT Libraries Government Documents Department

Fluorine Micas

Description: From Abstract: "In the report, detailed data and descriptions are given on compositions, syntheses, products, and uses, and on the properties including physical, dielectric, chemical, X-ray, optical, and structural."
Date: unknown
Creator: Shell, Haskiel R. & Ivey, Kenneth H.
Partner: UNT Libraries Government Documents Department

An Ultrasonic Measurement System for The Precise Determination of the Elastic Moduli of Single Crystals

Description: From Abstract: "The equipment described in this paper is based on the technique developed by McSkimin. Figure 1 shows a block diagram of the system. The oscilloscope presentation with no specimen present appears as shown in Figure 2a. At discrete frequencies, the pattern appears as shown in Figure 2b."
Date: May 1961
Creator: Renken, C. J.
Partner: UNT Libraries Government Documents Department

Bibliography on Molecular and Crystal Structure Models

Description: Report that briefly describes many of the models of crystal and molecular structures which have appeared in the literature, and presents a bibliography of the publications, grouped according to model types, which describe the models in more detail.
Date: May 20, 1960
Creator: Smith, Deane K.
Partner: UNT Libraries Government Documents Department

Survey of the Solid State Conformation of Calix[4]arenes

Description: The characteristics of seventy-six calix[4]arene crystal structures derived from the Cambridge Crystallographic Database are presented. This survey is a discussion of the inter and intramolecular effects on the solid state cavity shape and molecular recognition ability of the compounds. In addition to this survey, four new calix[4]arene crystal structures are presented. The conformational characteristics of these four calixarenes are determined by a complicated array of inter and intramolecular interactions in the crystal packing.
Date: August 1997
Creator: Obrey, Stephen J. (Stephen James)
Partner: UNT Libraries

A REVIEW OF THE MATHEMATICAL FORMULATION OF THE PROBLEM OF INELASTIC NEUTRON SCATTERING BY POLYCRYSTALLINE MATERIAL

Description: A self-contained development of the formulation of the problem of inelastic neutron scattering by crystals is presented. Although nearly all of the methods and results used in the discussion have appeared in a variety of previously published papers, additional mathematical details are given here which were found to aid in understanding the final results. (auth)
Date: June 1, 1959
Creator: Preskitt, C A
Partner: UNT Libraries Government Documents Department

Research on micro-sized acoustic bandgap structures.

Description: Phononic crystals (or acoustic crystals) are the acoustic wave analogue of photonic crystals. Here a periodic array of scattering inclusions located in a homogeneous host material forbids certain ranges of acoustic frequencies from existence within the crystal, thus creating what are known as acoustic (or phononic) bandgaps. The vast majority of phononic crystal devices reported prior to this LDRD were constructed by hand assembling scattering inclusions in a lossy viscoelastic medium, predominantly air, water or epoxy, resulting in large structures limited to frequencies below 1 MHz. Under this LDRD, phononic crystals and devices were scaled to very (VHF: 30-300 MHz) and ultra (UHF: 300-3000 MHz) high frequencies utilizing finite difference time domain (FDTD) modeling, microfabrication and micromachining technologies. This LDRD developed key breakthroughs in the areas of micro-phononic crystals including physical origins of phononic crystals, advanced FDTD modeling and design techniques, material considerations, microfabrication processes, characterization methods and device structures. Micro-phononic crystal devices realized in low-loss solid materials were emphasized in this work due to their potential applications in radio frequency communications and acoustic imaging for medical ultrasound and nondestructive testing. The results of the advanced modeling, fabrication and integrated transducer designs were that this LDRD produced the 1st measured phononic crystals and phononic crystal devices (waveguides) operating in the VHF (67 MHz) and UHF (937 MHz) frequency bands and established Sandia as a world leader in the area of micro-phononic crystals.
Date: January 1, 2010
Creator: Fleming, James Grant; McCormick, Frederick Bossert; Su, Mehmet F.; El-Kady, Ihab Fathy; Olsson, Roy H., III & Tuck, Melanie R.
Partner: UNT Libraries Government Documents Department

Three-Dimensional Silicon Photonic Crystals

Description: In this work, we report the realization of a series of silicon 3D photonic crystals operating in the infrared (IR), mid-IR and most importantly the near-IR (k= 1 -2pm) wavelengths. The structure maintains its crystal symmetry throughout the entire 6-inches wafer and holds a complete photonic bandgap.
Date: December 4, 1998
Creator: Biswas, R.; Fleming, J.G.; Hetherington, D.L.; Ho, K.M.; Lin, S.; Sigalas, M.M. et al.
Partner: UNT Libraries Government Documents Department

Holographic fabrication of 3D photonic crystals through interference of multi-beams with 4 + 1, 5 + 1 and 6 + 1 configurations

Description: This article fabricates 3D photonic crystals or quasi-crystals through single beam and single optical element based holographic lithography.
Date: September 9, 2014
Creator: George, David; Lutkenhaus, Jeffrey; Lowell, David; Moazzezi, Mojtaba; Adewole, Murthada; Philipose, Usha et al.
Partner: UNT College of Arts and Sciences

Plastic Deformation of Aluminum Single Crystals at Elevated Temperatures

Description: Note presenting the results of a comprehensive study of plastic deformation of aluminum single crystals over a wide range of temperatures. The results of constant-stress creep tests have been reported for the temperature range from 400 to 900 degrees Fahrenheit. In constant-load creep tests at temperatures up to 1100 degrees Fahrenheit, four additional slip planes have been observed, besides the customary plane.
Date: April 1955
Creator: Johnson, R. D.; Young, A. P. & Schwope, A. D.
Partner: UNT Libraries Government Documents Department