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Displaying 3976 - 4000 of 74647

Renewable Standard Reference Material for the Detection of TP53 Mutations

October 12, 2021
Author(s)
C D. O'Connell, L A. Tully, J E. Devaney, M A. Marino, J P. Jakupciak, Donald H. Atha
It is important to have standards for use in mutation detection systems to monitor the sensitivity of mutation detection and the possible introduction of errors during amplification and separation procedures. We have developed 12 plasmid clones containing

Representation of Zn(II) Complexes in Polarizable Molecular Mechanics. Further Refinements of the Electrostatic and Short-Range Contribution of the Intermolecular Interaction Energy. Comparisons With Parallel Ab Initio Computations

October 12, 2021
Author(s)
N. Gresh, F M. Piquemal, Morris Krauss
Accurate molecular mechanics potentials are required for the representation of metal binding sites in proteins. These potentials must reproduce accurate quantum mechanics potential energy surfaces. This study is the most recent refinement of the SIBFA (Sum

Resistance Heating of the Gasket in a Gem-Anvil High Pressure Cell

October 12, 2021
Author(s)
N M. Balzaretti, E J. Gonzalez, Gasper J. Piermarini, T Russell
The design and fabrication of a modified gem-anvil high pressure cell capable of statically heating gasketed samples to temperatures in the range of 1100 degrees C at pressures up to 4.0 Gpa is described. The high temperatures were achieved by resistance

Ring-on-Ring Strength Measurements on Rectangular Glass Slides

October 12, 2021
Author(s)
Theo Fett, G Rizzi, J -. Guin, Sheldon M. Wiederhorn
The ring-on-ring test has been standardized and used extensively for strength measurements on glasses and ceramics. The specimen is especially useful to avoid edge defects that often dominate the failure of flexure bars. In this paper, we extend the

Robust Design of an Evolutionary Algorithm for Machining Optimization Problems

October 12, 2021
Author(s)
Jean-Louis Vigouroux, Laurent Deshayes, Sebti Foufou, James J. Filliben, Lawrence A. Welsch, Alkan Donmez
In this paper, a methodology for the robust design of an evolutionary algorithm is presented. The evolutionary algorithm (EA) is studied with the intention to solve machining optimization problems having highly non linear constraints and uncertainties. A

Role of Substrate Material in Failure of Crown-Like Layer Structures

October 12, 2021
Author(s)
Jeonghwan Kim, Sanjit Bhowmick, Herzl Chai, Brian R. Lawn
The role of substrate modulus on critical loads to initiate and propagate radial cracks to failure in curved brittle glass shells on compliant polymeric substrates is investigated. Flat glass disks are used to drive the crack system. This configuration is

Rotational Spectra, Nuclear Quadrupole Hyperfine Tensors, and Conformational Structures of the Mustard Gas Simulent Chloroethyl Ethyl Sulfide

October 12, 2021
Author(s)
M J. Tubergen, A Lesarri, R D. Suenram, A C. Samuels, J O. Jensen, M W. Ellzy, J M. Lochner
Rotational spectra have been recorded for both the 35Cl and 37Cl isotopes of two structural conformations of chloroethyl ethyl sulfide (CEES). The rotational constants of the 35Cl and 37Cl isotopomers were used to identify the conformations as GGT and TGT

Satellite Instrument Calibration for Measuring Global Climate Change

October 12, 2021
Author(s)
G Ohring, B Wielicki, R Spencer, W Emery, Raju V. Datla
Measuring the small changes associated with long-term global climate change from space is a daunting task. The satellite instruments must be capable of observing atmospheric temperature trends as small as 0.10 degrees C / decade, ozone changes as little as

Science for Stewardship: Multidisciplinary Research on the USS Arizona

October 12, 2021
Author(s)
Matthew A. Russell, L E. Murphy, D L. Johnson, Timothy J. Foecke, Pamela J. Morris, R Mitchell
The National park Service's Submerged Resources Center and USS Arizona Memorial are conducting and coordinating research directed at understanding the nature and rate of natural processes affecting the deterioration of the USS Arizona in Peal Harbor

Secondary Phase Evolution in Silicon Nitride During Creep and Heat Treatment

October 12, 2021
Author(s)
F Lofaj, H Gu, A Okada, Sheldon M. Wiederhorn, H Kawamoto
The microstructure of a ytterbia- and yttria-containing grade of silicon nitride, SN 88, was investigated after it had been annealed in nitrogen, in air and crept in air. We were particularly interested in phase transformation within the secondary silicate

Self-Assembled Multiferroic Nanostructures in CoFe 2 O 4- PbTiO 3 System

October 12, 2021
Author(s)
Jiying Li, Igor Levin, Julia Slutsker, Virgil Provenzano, Peter K. Schenck, J.H. Yang, Alexander L. Roytburd
The effect of substrate orientation of the morphologies of epitaxial self-assembled nanostructures was demonstrated using newly synthesized multiferroic 0.67PbTiO3-0.33CoFe2O4 nanocomposite thin films. The two-phase nanostructures were grown on single

Self-Organization of Self-Assembled Tetrameric Porphyrin Arrays on Surfaces

October 12, 2021
Author(s)
T Milic, Jayne C. Garno, T. Saab, G Smeureanu, J Batteas, Charles M. Drain
The incorporation of designed self-assembled supramolecular structures into devices requires deposition onto surfaces with retention of both structure and function. This remains a significant challenge and presents a barrier to developing devices with

Shape of Hollow Dislocation Cores: Elastic and Anisotropic Surface Energy Effects

October 12, 2021
Author(s)
David J. Srolovitz, N Sridhar, J P. Hirth, John W. Cahn
Evidence for the existence of hollow core dislocations has existed for nearly forty years. Such hollow cores are often found in growth spirals associated with screw dislocations. Examples of this type of morphology may be found in silicon carbide, copper

Simulating Thermal Response of EB-PVD Thermal Barrier Coating Microstructures

October 12, 2021
Author(s)
M Bartsch, U Schulz, J M. Dorvaux, O Lavigne, Lin-Sien H. Lum, Stephen A. Langer
As ceramic thermal barrier coatings (TBC) are used in more critical applications in advanced engines, knowing basic physiproperties of TBC's is essential for design and reliability assessment. In particular, knowledge of thermal conductivity is cruciin

Simulation of a Single Asperity Impacts at Head-Disk Interface

October 12, 2021
Author(s)
Tze J. Chuang, Stephen M. Hsu
During the track accessing mode of a hard disk drive, the flying height of the slider over the disk surface becomes smaller and smaller as the demand in data storage a real density increases. As a result, the propensity of glide avalanche is bound to

SiO 2 /Si 3 N 4 /A1 2 O 3 Stacks on Silicon for Scaled-Down Memory Devices: Effects of Interfaces and Thermal Annealing

October 12, 2021
Author(s)
M Lisiansky, A Heiman, M Kovler, Y Roizin, Igor Levin, A Gladkikh, M Oksman, R Edrei, A A. Hofman, Y Shnieder, T Claasen
Effects of interfaces and thermal annealing on the electrical performance of the SiO2/Si3N4/A12O3 (ONA) stacks in non-volatile memory devices were investigated. Structural and electrical characterization demonstrated the principal role of the Si3N4/A12O3
Displaying 3976 - 4000 of 74647