| Relationship of Grain Boundary Structure and Mechanical Properties of Inconel 690 |
08 MAY 2009 |
140 pages |
| Authors:
Joseph J. Marra; MASSACHUSETTS INST OF TECH CAMBRIDGE
|
 | Stress corrosion cracking (SCC), failure due to environmentally assisted crack nucleation and propagation, is an important metallurgical problem with impact on current and future designs of ship structural components and nuclear reactors. SCC mechanism is dependent on the microstructure, particularly the grain boundaries, for a given alloy composition. This thesis investigated the relationship between the structural nature and the nanoscale mechanical properties on and near the grain boundaries to identify ... |
|
| High Efficiency, Room Temperature Mid-Infrared Semiconductor Laser Development for IR Countermeasures |
May-2009 |
21 pages |
| Authors:
Karen J Nordheden; Linda J Olafsen; KANSAS UNIV CENTER FOR RESEARCH INC LAWRENCE
|
| This purpose of this grant focused on the optical and electronic characterization and fabrication of antimonide-based semiconductor lasers for infrared applications. Recent results with Optical Pumping Injection Cavity (OPIC) lasers includes 4 micrometer emission from a broadband laser and the measurement of spatial and temporal beam profiles. From August 2006 through December of 2007, the work was expanded to include the development of plasma etch processes in an Oxford Instruments ... |
|
| DC Characteristics of InAs/AlSb HEMTs at Cryogenic Temperatures |
May 2009 |
3 pages |
| Authors:
G Moschetti; P -A Nilsson; N Wadefalk; M Malmkvist; E Lefebvre; J Grahn; Y Roelens; A Noudeviwa; A Olivier; S Bollaert; CHALMERS UNIV OF TECHNOLOGY GOETEBORG (SWEDEN) DEPT OF MICROELECTRONICS
|
| The Direct Current (DC) properties of 110-nm gate-length InAs/AlSb-based high electron mobility transistors (HEMTs) at cryogenic (30K) and room temperature (300K) were investigated. Compared to 300K, devices at 30K exhibited lower on-resistance (R (sub ON)) and output conductance (g (sub DS)), a higher transconductance (g sub m)), and a more distinct knee in the I (sub DS)(V (sub DS)) characteristics. The improvement in the DC performance at cryogenic temperature should ... |
|
| The Effects of Temperature and Electron Radiation on the Electrical Properties of AlGaN/GaN Heterostructure Field Effect Transistors |
Mar-2009 |
120 pages |
| Authors:
Jeffrey T Moran; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH GRADUATE SCHOOL OF ENGINEERING AND MANAGEMENT
|
| AlGaN/GaN Heterostructure Field Effect Transistors (HFETs) have come under increased study, in recent years, owing to their highly desirable material and electrical properties, ruggedness, and survivability even during and after exposure to extreme temperature and radiation environments. These devices or similar devices constructed of AlGaN and/or GaN materials are being researched for their potential applications in many military and space based systems. In this study, unpassivated and SiN passivated Al(0.27)Ga(0.73)N/GaN ... |
|
| Investigation of Electrical and Optical Properties of Bulk III-V Ternary Semiconductors |
Mar-2009 |
66 pages |
| Authors:
Travis C Gomez; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING AND MANAGEMENT/DEPT OF ENGINEERING PHYSICS
|
| Bulk grown III-V ternary semiconductors of In0.08Ga0.92Sb and In0.15Ga0.85As were investigated through Hall-effect and photoluminescence measurements to determine carrier concentration, mobility, sheet resistivity, and luminescence spectrum. In the past, epitaxial layers of ternary compounds have been grown on binary compound substrates, and thus very limited lattice matched ternary alloys were available. Recently, bulk grown ternary substrates have been developed, and it has presented a renewed interest in using these substrates ... |
|
| Radiometric Measurements on Ag/n-Si Composite Films for Detecting Radiation in the Earth's Atmospheric Windows |
20-Feb-2009 |
3 pages |
| Authors:
Bates; Clayton W Jr; HOWARD UNIV WASHINGTON DC
|
| The objectives of the research proposed in this 10-month effort were to assemble optical absorption and radiometric facilities for measuring the properties of Ag/n-Si composite films that are to be used as infrared detectors in the earth's atmospheric windows (1-2, 3-5, and 8-12 microns) from room temperature down to liquid nitrogen temperature and to begin making these measurements on films with specific microstructures. All of the equipment requested in the ... |
|
| Tunable, Room Temperature Light-emitting Diodes Based on Strained Si/SiGe Heterostructures |
24-Jan-2009 |
5 pages |
| Authors:
H H Cheng; G Sun; R A Soref; NATIONAL TAIWAN UNIV TAIPEI CENTER FOR CONDENSED MATTER SCIENCES
|
| This is the report of a project to engineer SiGe/Si heterostructures for a type-I band alignment in which the emission intensity at around 1 micrometer is enhanced over conventional Si-based diodes, and to develop sight-emitting diodes based on the novel type-I SiGe/Si heterostructure. |
|
| Development of a Multi-Scale Methodology for Prediction of the Microscopic Anisotropic Stress-Strain Response of Textured Metals under Dynamic Loading |
21-Jan-2009 |
69 pages |
| Authors:
Oana Cazacu; FLORIDA UNIV SHALIMAR DEPT OF MECHANICAL AND AEROSPACE ENGINEERING
|
| This report documents a comprehensive experimental and theoretical investigation of the deformation behavior of high-purity, polycrystalline alpha-titanium. A series of monotonic uniaxial compression and tension tests were carried out at room temperature under quasi-static conditions to quantify the plastic anisotropy and the tension-compression asymmetry of this material. The evolution of microstructure and texture during deformation was studied using optical image microscopy (OIM) and neutron-diffraction techniques to elucidate the role of ... |
|
| Sensitivity of Ion Absorption of Room Temperature Operating Single Electron Transistors |
Dec-2008 |
5 pages |
| Authors:
P S Karre; Paul L Bergstrom; Manoranjan Acharya; MICHIGAN TECHNOLOGICAL UNIV HOUGHTON
|
| Nanoelectronic devices form the building blocks of the nanoscaled systems and require innovative technologies for their realization. Single Electron Transistors (SET) is a novel class of nano transistor which operates on the principle of Coulomb blockade. Coulomb blockade effects become dominant when the device dimensions approach few nano-meters. The SET devices are potential candidates for applications in nano sensing, and data storage. Because of the smaller dimensions of the SET ... |
|
| Threshold Voltage Improvement and Gate Leakage Current Reduction in a Multi-dot Room Temperature Operating Single Electron Transistor (RT-SET) |
Dec-2008 |
5 pages |
| Authors:
Manoranjan Acharya; Daw D Cheam; P S Karre; Paul L Bergstrom; MICHIGAN TECHNOLOGICAL UNIV HOUGHTON DEPT OF ELECTRICAL AND COMPUTER ENGINEERING
|
| The single-electron transistor (SET) is one of the best candidates for future nano electronic circuits because of its ultralow power consumption and small size. SET devices operate on the principle of Coulomb blockade, which is more prominent at dimensions of a few nano meters. Typically, the SET device consists of two capacitively coupled ultra small tunnel junctions with a nano island between them. The electron tunneling through the tunnel junctions ... |
|
| Reversible Polymer Hydrogels |
Dec-2008 |
4 pages |
| Authors:
V M Boddu; N Naismith; H Patel; R C Flowers; ENGINEER RESEARCH AND DEVELOPMENT CENTER CHAMPAIGN IL CONSTRUCTION ENGINEERING RESEARCH LAB
|
| Temperature sensitive hydrogels based on N-isopropyl acrylamide (NIPA) and acryloyl glucosamine (AG) were synthesized using ammonium persulfate (APS) as initiator, N,N,N',N' -tetramethylenediamene (TEMED) as activator, and N,N'-methylene bisacrylamide (BIS) as cross-linker. The hydrogels were characterized using FTIR spectral analysis to investigate the chemical composition of the hydrogels. Swelling studies of the gel in water at room temperature to relate the swelling characteristics to the chemical composition were conducted. Further, the ... |
|
| Selected Research Highlights and Potential Impact for Army Applications |
Dec-2008 |
28 pages |
| Authors:
John D Joannopoulos; MASSACHUSETTS INST OF TECH CAMBRIDGE INSTITUTE FOR SOLDIER NANOTECHNOLOGIES (ISN)
|
| MISSION AND GOALS: To dramatically improve the survivability of the Soldier by working and extending the frontiers of Nano-technology through fundamental research ... and transitioning with our Army and Industry Partners. |
|
| Efficient THZ Source Based on Cascaded Optical Down-Conversion in Orientation-Patterned GaAs Structures |
20-Nov-2008 |
34 pages |
| Authors:
Konstantin Vodopyanov; David Bliss; Yun-Shik Lee; Walter Hurlbut; Vladimir Kozlov; James Harris; Anjie Lin; Xiaojun Yu; Paulina Kuo; Joe Schaar; Martin Fejer; Candace Lynch; STANFORD UNIV CA EDWARD L GINZTON LAB OF PHYSICS
|
| The goal of this DARPA TIFT project was to demonstrate an efficient room temperature source for THz imaging systems based on optical down-conversion in an orientation-patterned GaAs microstructure, incorporated into an optical resonant cavity, and pumped by a compact solid state laser. The main achievements are: (1) quasi-phase-matched (QPM) GaAs microstructures with periodic reversal of crystalline orientation, including orientation-patterned GaAs (OPGaAs), diffusion-bonded GaAs (DB-GaAs) and optically-contacted GaAs (OC-GaAs) suitable for ... |
|
| Optical Behavior of III-TM-N Materials and Devices |
26-Sep-2008 |
45 pages |
| Authors:
J Zavada; FLORIDA UNIV GAINESVILLE DEPT OF MATERIALS SCIENCE AND ENGINEERING
|
| Room temperature ferromagnetism has been observed in AlMnN grown by gas-source MBE. The lattice constant decreased with increasing Mn cell temperature for single phase material, indicating constant site occupation, probably substitutional. Hysteresis in M vs. H at room temperature was observed in single phase material and the magnetization as a function of temperature suggests ferromagnetism caused by AlMnN, not clusters. AlCrN was also investigated. Strong ferromagnetism persists to 350K (the ... |
|
| A Coupled Creep Plasticity Model for Residual Stress Relaxation of a Shot Peened Nickel-Base Superalloy (Postprint) |
Sep-2008 |
12 pages |
| Authors:
Reji John; Dennis J Buchanan; Robert A Brockman; Andrew H Rosenberger; DAYTON UNIV OH RESEARCH INST
|
| Shot peening is a commonly used surface treatment process that imparts compressive residual stresses into the surface of metal components. Compressive residual stresses retard initiation and growth of fatigue cracks. During the component loading history, loading, or during elevated temperature static loading, such as thermal exposure and creep. In these instances, taking full credit for compressive residual stresses would result in a methodical approach for characterizing and modeling residual stress ... |
|
| Modulation of Coulomb Blockade Behavior of Room Temperature Operational Single Electron Transistors by Tunnel Junction |
Aug-2008 |
5 pages |
| Authors:
P S Karre; Aditya Kapoor; Govind Mallick ;Shashi P Karna; Paul L Bergstrom; MICHIGAN TECHNOLOGICAL UNIV HOUGHTON DEPT OF ELECTRICAL AND COMPUTER ENGINEERING
|
| The effect of tunneling oxide thickness on the Coulomb blockade behavior of a room temperature operating multi dot Single Electron Transistors (SET) was investigated. Our room temperature operational SETs, fabricated from focused ion beam deposited tungsten nano-islands, clearly show the modulation of Coulomb Blockade voltage with the change in the tunnel oxide thickness. The Coulomb blockade voltage of the device was increased from 2.0 V to 5.0 V by the ... |
|
| Equation of State of Ballistic Gelatin |
23-Jun-2008 |
40 pages |
| Authors:
Muhetaer Aihaiti; Russell J Hemley; CARNEGIE INST OF WASHINGTON DC
|
| We determined the equation of state for ballistic gelatin using the Brillouin scattering spectroscopy with a diamond anvil cell by measuring the pressure dependence of the sound velocities from ambient pressure to 12 GPa at room temperature. We extended these measurements to a temperature range of 0 to 100 deg C between ambient and 12 GPa. We analyzed the Brillouin data using a high temperature Vinet equation of state and ... |
|
| High Al-content AlGaN Alloys for Deep UV Laser Applications |
16-Jun-2008 |
10 pages |
| Authors:
Hongxing Jiang; Jingyu Lin; KANSAS STATE UNIV MANHATTAN
|
| We have carried out the growth and systematic studies of the optoelectronic and structural properties of AlN epilayers. The results revealed that the threading dislocation (TD) density, in particular the edge TD density, decreases considerably with increasing the epilayer thickness. The screw dislocation density was estimated to be about 5x106 cm-2 in the 4 ?m thick AlN epilaye and is more than one order of magnitude lower than that in ... |
|
| Magnetic Sensors with Picotesla Magnetic Field Sensitivity at Room Temperature |
Jun-2008 |
17 pages |
| Authors:
Sy-Hwang Liou; NEBRASKA UNIV LINCOLN DEPT OF PHYSICS AND ASTRONOMY
|
| High sensitivity magnetic sensors will have a significant impact on security, industry, and quality of life. Many of these applications require sensitivities better than 1 nT/Hz1/2 as well as low cost, small size, low maintenance, and low power consumption. This project is to develop highly sensitive magnetic sensors that fit the goal of the MMSON-07-03 Statement of Need. This need is to develop novel sensors applicable to the diverse detection ... |
|
| The Study and Development of Metal Oxide Reactive Adsorbents for the Destruction of Toxic Organic Compounds |
15 APR 2008 |
22 pages |
| Authors:
Mark B. Mitchell; CLARK ATLANTA UNIV GA
|
| The achievements realized during the course of this project provide an important alternative method for mitigating the effects of the exposure of personnel and systems to chemical warfare agents and other toxic organic compounds. The research program that was developed built upon earlier results achieved in the room temperature oxidative decomposition of a chemical warfare agent simulant, dimethyl methylphosphonate (DMMP), on solid reactive adsorbents and examined ways of improving those ... |
|
| Laser Manipulation of Nuclear Transitions |
14 APR 2008 |
15 pages |
| Authors:
Olga Kocharovskaya; TEXAS A AND M UNIV COLLEGE STATION DEPT OF PHYSICS
|
| The project is focused on theoretical and experimental studies of the quantum coherence effects at the atomic and nuclear transitions in solids. The main results are the following. 1. Electromagnetically Induced Transparency (EIT) and all-optical writing and probing of quantum coherence in room temperature solids are demonstrated experimentally in the first time. 2. The method for coherent suppression of excited state absorption in laser crystals is suggested. It opens the ... |
|
| Spin-Precession Organic Magnetic Sensor |
11-Apr-2008 |
43 pages |
| Authors:
Srini Krishnamurthy; SRI INTERNATIONAL MENLO PARK CA
|
| The three major tasks we addressed in this project were to: (a) identify the issues for demonstration of a polymer-based spin-precession magnetic sensor; (b) develop theoretical and computational techniques to study the effect of the interface between ferromagnetic metal and polymers for FET applications; and (c) apply the existing light propagation codes to study transmission of 1.5 micron wavelength light through GaAs. We have completed all three tasks, and the ... |
|
| The Effect of Elevated Temperature on the Fretting Fatigue Behavior of Nickel Alloy IN-100 |
APR 2008 |
122 pages |
| Authors:
John F. Ownby; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING AND MANAGEMENT
|
| This thesis studied the effect of elevated temperature (600 C) on the fretting fatigue behavior of IN-100. First, fretting and plain fatigue S-N curves were determined over a large range of applied stress at an identical stress ratio of 0.03 at 600 C and for fretting tests, with a constant contact load. The partial slip condition was verified by using hysteresis between shear force and axial stress techniques. The contact ... |
|
| 3-5 Micrometers Room Temperature Operated CW Laser Diodes Based on Novel InGaAsNSb Material System |
14 MAR 2008 |
21 pages |
| Authors:
Gregory Balenky; STATE UNIV OF NEW YORK
|
| Novel mid-IR photonic device technology has been developed. High power room temperature operated diode lasers for spectral region above 3 micrometer have been designed and fabricated. 120mW CW output power level was obtained at 3 micrometer and 80 mw CW at 3.1 micrometer at room temperature. More than 200mW CW output was obtained near 3 micrometer at temperatures accessible with thermo-electric cooling. We demonstrate a double-quantum-well GaSb-based diode laser operating ... |
|
| Strain and Quantum Dots Manipulation in Nitride Compounds for Opto-electronic Devices |
15 FEB 2008 |
8 pages |
| Authors:
S. M. Bedair; N. A. El-Masry; NORTH CAROLINA STATE UNIV AT RALEIGH OFFICE OF CONTRACTS AND GRANTS
|
| Activities during the project period can be divided into two main areas. The first dealt with quantum structure and optical properties of light sources based on GaInN/AlInGaN quantum well structures. The second area covered research in the room temperature ferromagnetic properties of GaMnN dilute magnetic semiconductors. |
|
| Electro-Responsive Behaviour Multi-Wall Nanotubes/Gelatin Composites and Cross-Linked Gelatin Electrospun Mats |
11 FEB 2008 |
26 pages |
| Authors:
Soo-Young Park; KYUNGPOOK NATIONAL UNIV DAEGU (SOUTH KOREA) DEPT OF POLYMER SCIENCE
|
| Swelling, states of water, morphology, stability in the aqueous solution, and electro-mechano- chemical bending behaviors of the gelatin/chitosan blend system were studied in order to clarify the potential use of this blend system as an actuator. The gelatin/chitosan blend system was prepared in order to avoid dissolution of the pure chitosan film system in an aqueous medium and the rigidity and easy degradation of the pure gelatin system in the ... |
|
| Electromagnetic Characterization of YBa2Cu3O7-Delta Thin Films with Calcium Doping for Bi-Crystal Grain Boundary Conductivity Enhancement (Postprint) |
08 Feb 2008 |
8 pages |
| Authors:
Richard A Kleismit; Gregory Kozlowski; Angela L Campbell; Timothy J Haugan; Rand R Biggers; Paul N Barnes; Timothy L Peterson; Iam Maartense; Simon C Hopkins; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH PROPULSION DIR/POWER DIV/MECHANICAL ENERGY CONVERSION BRANCH
|
| The objective of this study was to examine the transport properties of two YBa2Cu3O7-delta thin films with (Y0.9Ca0.1)2BaCuO5 additions deposited on vicinal SrTiO3 6 deg. bi-crystal substrates and to investigate the possible correlations between spatial calcium distribution and local electromagnetic properties across bi-crystal grain boundaries using evanescent microwave microscopy (EMM) and atomic force microscopy (AFM). The samples under consideration differed in transport critical current measurements by a factor of two ... |
|
| Thermal Characterization of Thin Films for MEMS Applications |
FEB 2008 |
20 pages |
| Authors:
David J. Howe; Brian Morgan; ARMY RESEARCH LAB ADELPHI MD SENSORS AND ELECTRON DEVICES DIRECTORATE
|
| Thin film dielectrics play an important role in the fabrication and processes involved with microelectromechanical systems (MEMS). Two such dielectrics that are used widely are silicon dioxide (SiO2) and photoresist. As a large portion of these systems use the conduction of heat through SiO2 and photoresist layers, the thermal conductivity of these materials is crucial. In this work, the thermal conductivities of the above mentioned materials were determined using a ... |
|
| Preparation, Electromechanical, and Structural Study of Carbon Nanotube/Gelatin Nanocomposites |
15 JAN 2008 |
32 pages |
| Authors:
Soo-Young Park; KYUNGPOOK NATIONAL UNIV DAEGU (REPUBLIC OF KOREA)
|
| Multi-walled carbon nanotube "MWNT"/gelatin composites by dispersion of MWNT through ultrasonication in an aqueous medium with anionic surfactant sodium dodecyl sulfate "SDS". The swelling behavior and the bending mechanism of the composite and pure gelatin films were studied in order to clarify the potential use of MWNT in the gelatin actuator. The response of the composite and pure hydrogel to the applied electrical field in the NaCl aqueous solution was ... |
|
| Liquid Azide Salts and Their Reactions with Common Oxidizers IRFNA and N2O4 (Postprint) |
Jan-2008 |
9 pages |
| Authors:
Stefan Schneider; Michael Rosander; Steven Chambreau; Tommy Hawkins; Jeffrey Mills; Ghanshyam Vaghjiani; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
|
| Several imidazolium-based ionic liquid azides with saturated and unsaturated side chains were prepared and their physical and structural properties were investigated. The reactivity of these new as well as some previously reported ionic liquid azides with the strong oxidizers, N2O4 and inhibited, red-fuming-nitric acid (IRFNA), were studied. |
|
| Performance Optimization of Fe-Based Light Emitting Diodes |
10 DEC 2007 |
5 pages |
| Authors:
Athos Petrou; STATE UNIV OF NEW YORK AT BUFFALO AMHERST RESEARCH FOUNDATION
|
| We have evaluated the performance of a new type of Fe spin-LED in which recombination takes place in InAs monolayers grown at the intrinsic region of an n-i-p AlGaAs(n)/GaAs(i)/AlGaAs(p) diode. The intrinsic region is a wide GaAs quantum well. The InAs layer is known as the "wetting layer" (WL). The new WL spin-LEDs were found to have the same high circular polarization as the more conventional Fe spin-LEDs , but ... |
|
| Electrical Activation Studies of Silicon Implanted Aluminum Gallium Nitride with High Aluminum Mole Fraction |
DEC 2007 |
311 pages |
| Authors:
Elizabeth A. Moore; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING AND MANAGEMENT
|
| This research demonstrates a method for producing highly conductive Si-implanted n-type aluminum gallium nitride (AlxGa1-xN) alloys, and represents a comprehensive analysis of the resulting material's electrical and optical properties as a function of Al mole fraction, anneal temperature, anneal time, and implantation dose. Highly conductive alloys are critical to the fabrication of devices operating in deep UV, high-temperature, high-power, and high-frequency environments, and thus this research is significant in regard ... |
|
| Development of THz Fiber Lasers |
12-Sep-2007 |
8 pages |
| Authors:
Xi-Cheng Zhang; Albert Redo-Sanchez; Gernot S Pomrenke; RENSSELAER POLYTECHNIC INST TROY NY
|
| There is no Current commercially available THz fiber Laser on the market, and there is no any report successful demonstration of THz fiber lasers in literatures. Our DURIP project is to develop a THz fiber Laser on a novel photonic crystal fiber technique. The THz fiber laser has several important characteristics; sm portability, room temperature operation, and high output power. ALL provide advantages over current THz La a new high-power, ... |
|
| Processing of Training Range Soils for the Analysis of Energetic Compounds |
SEP 2007 |
34 pages |
| Authors:
Alan Hewitt; Susan Bigl; Marianne Walsh; Sylvie Brochu; Kevin Bjella; Dennis Lambert; ENGINEERING RESEARCH AND DEVELOPMENT CENTER HANOVER NH COLD REGIONS RESEARCH AND ENGINEERING LAB
|
| Large soil samples are often necessary to represent areas where analytes are distributed as particulates. Proper processing of these large samples impose additional time, space, and equipment requirements on the laboratory community servicing environmental programs to investigate military training ranges. Part of this study evaluated the robustness of two methods used to process large soil samples for the determination of energetic munitions residues whole sample mechanical grinding (comminution) and solvent ... |
|
| Structural, Thermodynamic, and Functional Mechanisms of Adaptations WrbA and AdoMetDC Proteins in Extremophilic Organisms |
15 AUG 2007 |
21 pages |
| Authors:
George Makhatadze; PENNSYLVANIA STATE UNIV COLL OF MEDICINE HERSHEY
|
| One of the open questions of structural biology is the understanding of the mechanisms %by which enzymes adapt to extreme temperatures, both high (thermophilic) and low (psychrophilic). A model protein used in this study, S-adenosyl-methionine decarboxylase (AdoMetDC), is a key enzyme in the polyamine biosynthesis and thus its activity should be strongly dependent on the environmental variables such as temperature. To date we completed the experimental characterization of the thermophilic ... |
|
| Alkene- and alkyne- substituted methylimidazolium bromides: structural effects and Physical properties (Postprint) |
Aug-2007 |
8 pages |
| Authors:
Stefan Schneider; Gregory Drake; Leslie Hall; Tommy Hawkiins; Michael Rosander; Dennis Smith; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
|
| Several bromide salts composed of methylimidazolium cations possessing unsaturated sidechains (allyl-, 3-butenyl-, propargyl-, 2-butynyl-, and 2-pentynyl-) have been synthesized and characterized by multinuclear NMR, vibrational spectroscopy, and DSC, X-ray and elemental analysis. X-ray structures of 1-(2-butynyl)-3-methylimidazolium bromide, 1-propargyl-3-methylimidazolium bromide as well as the X-ray structure of 1-allyl-3- methylimidazolium bromide which was previously identified as a room temperature ionic liquid, were all determined. |
|
| Quantum Computing in Diamond |
28 MAY 2007 |
13 pages |
| Authors:
Steven Prawer; MELBOURNE UNIV VICTORIA (AUSTRALIA)
|
| The aim of this proposal is to demonstrate the key elements needed to construct a logical qubit in diamond by exploiting the remarkable quantum properties of the nitrogen-vacancy (NV) optical centre. Specifically, the focus of the work was to address the materials and fabrication issues. We have demonstrated (i) that individual NV qubits can be fabricated by ion implantation with long coherence times (>350 microseconds at room temperature), (ii) electrical ... |
|
| Symposium Q: Magnetic Thin Films, Heterostructures, and Device Materials |
22 MAY 2007 |
25 pages |
| Authors:
William Bailey; MATERIALS RESEARCH SOCIETY WARRENDALE PA
|
| In Symposium Q on Magnetic Thin Films, Heterostructures, and Device Materials, spin-dependent tunneling junctions were presented, with a particular focus on Fe/MgO/Fe junctions. Tunneling magnetoresistance values in this system have recently attained up to 350% at room temperature, several times higher than those seen in any other materials system. High magnetoresistance values were presented experimentally, treated through ab initio models, and correlated with MgO barrier structure by in situ STM ... |
|
| Study of Cryogenic Complex Plasma |
26 APR 2007 |
9 pages |
| Authors:
Osamu Ishihara; Yoshiharu Nakamura; Masako Shindo; Chikara Kijima; YOKOHAMA NATIONAL UNIV (JAPAN) FACULTY OF ENGINEERING
|
| This Report describes the investigation entitled by "Study of Cryogenic Complex Plasma." The research has been carried out at Yokohama National University. Our overall goal is to study the cryogenic complex plasma experimentally and theoretically and to reveal novel natures of cryogenic complex plasma produced by a stable discharge above or in superfluid liquid helium. Two Dewar bottles, YD-1 (Yokohama Dewar 1) and YD-2 (Yokohama Dewar 2), accommodate cryogenic plasma ... |
|
| Room-Temperature, Near IR Fluorescence of High Optical Quality KTP (Postprint) |
APR 2007 |
10 pages |
| Authors:
S. M. Hegde; K. L. Schepler; R. D. Peterson; D. E. Zelmon; DAYTON UNIV OH RESEARCH INST
|
| We investigated room temperature fluorescence in the 500-900nm spectral region from high optical quality, polished and uncoated KTP crystals from three different commercial vendors. The crystals were all cut into 5x5x5 mm3 cubes with their dielectric axes along the cube edges. The pump source was a tripled Nd:YAG laser operating at 355nm and 7mJ energy having 3ns pulse width and 100Hz pulse repetition rate. Samples from two vendors showed low ... |
|
| Development of a Flow-Through SQUID System for Non-Destructive Evaluation of MRI Wire |
23 MAR 2007 |
3 pages |
| Authors:
Frederick C. Wellstood; MARYLAND UNIV COLLEGE PARK DEPT OF PHYSICS
|
| This project developed techniques to detect small defects in NbTi magnet wire at room-temperature using a flow-through high-transition temperature (Tc) superconducting quantum interference device (SQUID) system. The ability to detect small defects in km-long sections of NbTi magnet wire could improve the production yield of high-field magnets for power and medical applications. Such magnets are wound from continuous sections of wire up to 1 km long, and a single small ... |
|
| A Broadband High Spectral Brightness Fiber Based Two-Photon Source |
19 MAR 2007 |
8 pages |
| Authors:
Jingyun Fan; Alan L. Migdall; NATIONAL INST OF STANDARDS AND TECHNOLOGY GAITHERSBURG MD
|
| After characterizing the Raman scattering in a fused silica polarization-maintaining microstructure optical fiber, we built a fiber-based two-photon light source of high spectral brightness, broad spectral range, and very low noise background at room temperature. The resulting bright low-noise two-photon light can be used for a number of quantum information applications. |
|
| Ln3+-Catalyzed Alcoholysis of Organophosphates: New Methodology for the Catalytic Transformation of Phosphorus Pesticides and CW Agents |
14 MAR 2007 |
13 pages |
| Authors:
Robert S. Brown; QUEEN'S UNIV KINGSTON (ONTARIO)
|
| The title project involved investigation of the metal ion catalyzed alcoholysis (e.g. methanolysis) of neutral organophophorus (OP)ester compounds. These included several members of the phosphate [(ArO)(RO)2P=O] and phosphorothioate [(ArS)(RO)2P=O] classes, as well as phosphonate [(ArO)CH3(OR)P=O] and phosphonothioate [(ArS)CH3(RO)P=O] classes. Some work was conducted on the P=S phosphorothionate esters which are common pesticides. In general it was found that La3+ ion, in the presence of one equivalent of alkoxide, provided an ... |
|
| Cobalt Doping of Semiconducting Boron Carbide Using Cobaltocene |
MAR 2007 |
100 pages |
| Authors:
Lonnie Carlson; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH
|
| The decomposition of cobaltocene and metacarborane (closo-1,7-dicarba-decaborane) under low energy electron irradiation at about 200 K results in a material with the Fermi level closer to the valence band than the material resulting from the decomposition of metacarborane alone. This indicates that cobaltocene provides a relatively p-type dopant as seen in ultraviolet photoemission spectroscopy/inverse photoemission spectroscopy. Upon warming to room temperature, however, the Fermi level shifts towards the conduction band, ... |
|
| Comparison of Matrix Cracking in High Temperature and Lower Temperature PMCs from Cryogenic Exposure (Preprint) |
MAR 2007 |
11 pages |
| Authors:
Vernon T. Bechel; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH STRUCTURAL MATERIALS BRANCH/NONMETALLIC MATERIALS DIV
|
| The behavior of a high temperature carbon/polyimide composite, T650/AFR-PE-4, in a cryogenic environment was studied. The results were compared to results from similar testing of a carbon/epoxy and a carbon/bismaleimide composite to begin to scale the difficulties involved with using high temperature polymer matrix composites (PMCs) in cryogen containers on launch vehicles. T650/AFR-PE-4 developed transverse cracks in all plies after fewer cycles than the carbon/bismaleimide (IM7/5250-4) when each was cycled ... |
|
| Modeling of THz Quantum Cascade Lasers for Room Temperature Operation |
10-Jan-2007 |
18 pages |
| Authors:
Paolo Lugli; TECHNICAL UNIV OF MUNICH (GERMANY) INST FOR NANOELECTRONICS
|
| The terahertz frequency region spans the range between 0.3 and 10 THz. There is a considerable need for practical THz sources, notably for defence-oriented applications such as the detection of biological and chemical materials, imaging through persons or container walls, and secure short-distance communication through the atmosphere. However, electronics-based radiation sources generally operate at frequencies below the THz regime, while photonic sources usually are efficient above - thus, the THz ... |
|
| Single Spin Readout for the Silicon-Based Quantum Computer |
03 JAN 2007 |
13 pages |
| Authors:
P. C. Hammel; OHIO STATE UNIV COLUMBUS DEPT OF PHYSICS
|
| This report presents research funded under ARO grant DAAD19-02-1-0310 and conducted during the time period of 07/15/2002 - 07/14/2006. In the course of this research we have made major advancements in the development of Magnetic Resonance Force Microscopy (MRFM) on the way towards its application as a single spin readout for the silicon-based quantum computer. The main achievement of this work is the demonstration of electron spin resonance (ESR) signal ... |
|
| The Electronic Structure and Field Effects of an Organic-Based Room Temperature Magnetic Semiconductor |
01-Jan-2007 |
148 pages |
| Authors:
Derek M Lincoln; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH
|
| The future of spin-electronics or "spintronics" lies in the development of viable magnetic semiconductors that can effectively operate at room temperature Vanadium tetracyanoethylene (V[TCNE]~2) is a magnetic semiconductor with an ordering temperature well above that of room. Its highly disordered structure has hampered a comprehensive description of the interactions between the V and TCNE sublattices that give rise to its magnetic and electrical properties. We report the results of high-resolution ... |
|
| SR-1447 Fracture Mechanics Characterization of Aluminum Alloys for Marine Structural Applications |
JAN 2007 |
258 pages |
| Authors:
J. K. Donald; FRACTURE TECHNOLOGY ASSOCIATES PLEASANT VALLEY PA
|
| The Ship Structure Committee (SSC) identified a lack of information required for structural integrity and damage tolerance analyses of aluminum marine structures. The development of such data is vital in light of the increased use of aluminum alloys in marine construction. Under SSC project SR-1447, Fracture Technology Associates was contracted to characterize, through experimental fracture mechanics, the fatigue crack growth (FCG) resistance and fracture toughness of three aluminum alloys (5083, ... |
|
| Mid-IR Transition Metal Lasers (Postprint) |
JAN 2007 |
13 pages |
| Authors:
Kenneth L. Schepler; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH ELECTRO OPTICAL COUNTERMEASURES
|
| Transition metal ions have been of great interest from the beginning of laser development because of their broadband emission. The first demonstration of a transition metal laser used Ni2+ as the active ion in 1963. Other transition metal ions such as Co2+ have also been developed as lasers but low cross sections and the need for cryogenic cooling to achieve high efficiency hindered their transition from discovery to applications. The ... |
|
Reports by Keyword(s)
ROOM TEMPERATURE
