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Displaying 3701 - 3725 of 74638

Development of a Small and Portable Absolute Gravimeter

October 12, 2021
Author(s)
A L. Vitouchkine, J E. Faller
lhgh precision (10 -9-10 -8)g absolute ballistic gravimeters (ABGs) are now being used worldwide. The ballistic method is based on the measurement of time and distance changes during the free fall of a test mass (TM) in a vacuum. The movement of the TM

Development of an Emergency Procedures Manual Database (REPMD)

October 12, 2021
Author(s)
J J. La Rosa, P Motabar, Kenneth G. Inn, H Ziegler
A Radioanalytical Emergency Procedures Manual Database (REPMD) is currently under development at NIST. Its main objective is to act as a valuable reference and guide summarizing information available from many sources. It will provide quick access to

DEVELOPMENT OF NbN TERAHERTZ HEB MIXERS COUPLED THROUGH SLOT-RING ANTENNAS.

October 12, 2021
Author(s)
Eyal Gerecht, Dazhen Gu, Xin Zhao, John Nicholson, Fernando R. Morales, Sigfrid Yngvessen
In order to improve the power coupling to Phonon-Cooled Hot Electron Bolometric (PHEB)devices, we are experimenting with a different type of antenna. The goal of the project is to eliminate the need for a beam splitter or diplexer and to couple both the

Development of NbN THz HEB Mixer Devices and Films

October 12, 2021
Author(s)
Eyal Gerecht, V. A. Bhupathiraju, John Nicholson, Dazhen Gu, Yan Zhuang, Fernando R. Morales, Xin Zhao, Ric Zannoni, Sigfrid Yngvesson
Until recently, the thin-film NbN samples used by most PHEB research groups across the world have been produced in Moscow(MSPU). We have developed a process for fabricating thin NbN films at the National Institute of Standards and Technology (NIST) in

Dielectric Function of Wurtzite GaN and AIN Thin Films

October 12, 2021
Author(s)
L X. Benedict, Eric L. Shirley, T Wethkamp, K Wilmers, C Cobet, N Esser, W Richter, M Cardona
We present measurements and calculations of the dielectric function of wurtzite GaN and AIN. Spectroscopic ellipsometry was used to determine ε (omega) of thin film samples in the energy range from 3 eV to 9.8 eV. Calculations of ε (omega) for the bulk

Displacive Phase Transition in SrTiO 3 Thin Films Grown on Si(001)

October 12, 2021
Author(s)
F S. Aguirre-Tostado, A Herrera-Gomez, Joseph Woicik, R Droopad, Z Yu, D G. Schlom, E Karapetrova, P Zschack
Polarization dependent x-ray absorption fine structure measurements performed at the Ti K edge together with x-ray diffraction have been used to study the local structure in SrTiO3 thin films grown epitaxially on Si(001). SrTiO3 layers on Si(001) are found

Dopant Location Identification in Nd 3+ -Doped TiO 2 Nanoparticles

October 12, 2021
Author(s)
W Li, A I. Frenkel, Joseph Woicik, C Ni, S I. Shah
Doping large bandgap semiconductors is typically done in order to enhance photocatalytic, photovoltaic and other chemical and optoelectronic properties. The identification of dopant position and its local environment is essential to exploring the doping

Effects of Argon Gas-Cluster Ion Beam Processing on Surface Roughness, Crystalline Orientation Texture, Magnetic, and Giant Magnetoresistance Properties of A-Fe 2 O 3 Bottom Spin-Valves

October 12, 2021
Author(s)
S Bae, J H. Judy, P J. Chen, L Gan, William F. Egelhoff Jr., J Hautala
The effects of gas-cluster ion beam (GCIB) processing on the surface roughness, crystalline orientation texture, magnetic, and giant magneto resistance (GMR) properties of exchange biased anti-ferromagnetic (AF) oxide α-Fe 2O 3 bottom spin-vales (BSV) have

Effects of Aspect Ratio of Multi-Walled Carbon Nanotube on Flammability Properties of Polymer Nanocomposites

October 12, 2021
Author(s)
Bani Cipiriano, Takashi Kashiwagi, Srinivasa R. Raghavan, Ying Yang, E A. Grulke, Kazuya Yamammoto, John R. Shields, Jack F. Douglas
The effects of the aspect ratio of multi-walled carbon nanotube (MWNT) on viscoelastic properties and flammability properties of PS/MWNT nanocomposites are studied with two different MWNTs having average aspect ratios of 49 and 150. While no significant

Effects of Bond Coat Surface-Roughness on Residual Stresses of Thermal Barrier Coating Systems

October 12, 2021
Author(s)
C H. Hsueh, J Haynes, M Lance, P Becher, M Ferber, Stephen A. Langer, W Carter, W R. Cannon, Lin-Sien H. Lum
The adherence of plasma-sprayed thermal barrier coatings (TBCs) is dependent on mechanical interlocking at the interface between the ceramic top coat and the underlying metallic bond coat. A rough bond coat surface is required in order to establish

Effects of Solution pH and Surface Chemistry on the Post-Deposition Growth of Chemical Bath Deposited PbSe Nanocrystalline Films

October 12, 2021
Author(s)
Shaibai K. Sarkar, Shifi Kababya, Shimon Vega, Hagal Cohen, Joseph Woicik, A I. Frenkel, Gary Hodes
Chemical bath deposited PbSe films were subjected to post-deposition treatment with aqueous (typically 0.25 - 0.5 M) KOH. For films deposited using a citrate complex, this treatment resulted in dissolution of surface lead oxides (seen from XPS and EXAFS

Efficient Computation of Optical Forces With the Coupled Dipole Method

October 12, 2021
Author(s)
P C. Chaumet, Adel Rahmani, A Sentenac, Garnett W. Bryant
We present computational techniques to compute in an efficient way optical forces on arbitrary nanoobjects using the coupled dipole method. We show how the time of computation can be reduced by several orders of magnitude with the help of fast-Fourier

Elastic Modulus Measurements in Plasma Sprayed Deposits

October 12, 2021
Author(s)
Jay S. Wallace, J Ilavsky
A technique has been developed to characterize the elastic modulus of zirconium oxide-8% yttrium oxide plasma sprayed deposits. A commercial hardness indenter has been modified to record load-displacement as a spherical ball is elastically loaded onto the

Electro-optically derived millimeter-wave sources with phase and amplitude control

October 12, 2021
Author(s)
Bryan Bosworth, Nick Jungwirth, Kassi Smith, Jerome Cheron, Franklyn Quinlan, Ari Feldman, Dylan Williams, Nate Orloff, Chris Long
Integrated circuits are building blocks in millimeter-wave handsets and base stations, requiring nonlinear characterization to optimize performance and energy efficiency. Today's sources use digital-to-analog converters to synthesize arbitrary electrical

Electron Backscatter Diffraction Investigation of a Nano-Crystalline Pt Thin Film

October 12, 2021
Author(s)
T Maitland, X Han, Mark D. Vaudin, G R. Fox, M Coy
A polycrystalline Pt thin film deposited on a cut Si single crystal wafer coated with SiO2 and a TiO2 adhesion layer was studied using automated electron backscatter diffraction (EBSD). Integration of the EBSD detector and a scanning electron microscope
Displaying 3701 - 3725 of 74638