Results 91 to 100 of about 390,595 (315)

Artificial optical emissions at HAARP for pump frequencies near the third and second electron gyro-harmonic [PDF]

, 2005
International audienceHigh-power high-frequency radio waves beamed into the ionosphere cause plasma turbulence, which can accelerate electrons. These electrons collide with the F-layer neutral oxygen causing artificial optical emissions identical to ...
F. T. Djuth, T. Pedersen, A. Senior, Hughes, J., Gerken, E., E. Gerken, Marshall, R., Pedersen, T., Senior, A., McCarrick, M., R. Marshall, Djuth, F. T., Kosch, M. J., M. J. Kosch, D. Sentman, J. Hughes, M. McCarrick, Sentman, D.   +17 more
core   +1 more source

Slip Localization Intensification Mediated by Grain Boundary Sliding in a Polycrystalline Nickel‐Based Superalloy

Advanced Engineering Materials, EarlyView.
The temperature dependence of fatigue behavior in nickel‐based superalloys is investigated through high‐resolution measurements of plastic localization. While increasing temperature reduces localization and enhances fatigue performance in René 88DT, Inconel 718 exhibits a sharp degradation at intermediate temperature due to intensified slip ...
M. Calvat, D. Anjaria, I. Woo, C. Bean, D. Texier, J. C. Stinville   +5 more
wiley   +1 more source

Fatigue Crack Initiation and Growth in Nanocrystalline Ni at Multiple Length‐Scales

Advanced Engineering Materials, EarlyView.
Overview of miniaturized in situ SEM fatigue setup and resultant fatigue crack growth data for nanocrystalline Ni. The presented study focuses on the analysis of fatigue crack growth rate (FCGR) in focused ion beam‐notched microcantilevers prepared from nanocrystalline (NC) Ni as a model material.
Igor Moravcik, Alexander Jelinek, Markus Alfreider, Jutta Luksch, Anton Hohenwarter, Florian Schaefer, Christian Motz, Daniel Kiener   +7 more
wiley   +1 more source

Research progress on alkaline earth aluminates for dispenser cathodes

工程科学学报
Vacuum electron devices have wide applications in aerospace, radar communications, research equipment, and medical devices. They occupy an irreplaceable position in high-frequency, high-power microwave devices.
Zichen LI, Yunfei YANG, Yongfeng CAI, Zheng LIU, Junhao SUN, Hongmei LIU, Wenyuan ZHOU, Shizhong WEI, Jinshu WANG   +8 more
doaj   +1 more source

Influence of Test Temperature and Test Frequency on Fatigue Life of Aluminum Alloy EN AW‐2618A

Advanced Engineering Materials, EarlyView.
The influence of test temperature and test frequency on the fatigue life of EN AW‐2618A is investigated. High‐cycle fatigue tests are performed at different test temperatures and frequencies on the 1000 h/230°C overaged state. Both test parameters reduce fatigue life due to time‐dependent damage mechanisms.
Ying Han, Julian M. Rosalie, Jan Radners, Mauro Madia, Philipp von Hartrott, Birgit Skrotzki   +5 more
wiley   +1 more source

Observation of O+ 4P-4D0 lines in proton aurora over Svalbard

, 2004
Spectra of a proton aurora event show lines of O+ 4P-4D0 multiplet (4639–4696 Å) enhanced relative to the N2 +1N(0,2) compared to normal electron aurora. Conjugate satellite particle measurements are used as input to electron and proton transport models,
Ivchenko, N., Lanchester, B.S., Fordham, J., Galand, M., Rees, M.H., Lummerzheim, D., Furniss, I.   +6 more
core  

Formation of Saturn's ring spokes by lightning-induced electron beams

, 2006
Spokes are near-linear markings sometimes visible on Saturn's rings. They are widely accepted as being electrostatically-levitated sheets of similar to 0.6 micron-radius charged grains.
Lagg, A, Roussos, E, Mitchell, DG, Krüger, H., Jones, G., Arridge, C., McAndrews, HJ, Krupp, N., Krupp, N, Dougherty, MK, Jones, G. H., Woch, J, Arridge, C. S., Krimigis, S., Kruger, H, Ip, WH, Franz, M, Mitchell, D., Woch, J., Ip, W., McAndrews, H. J., McAndrews, H., Mitchell, D. G., Krimigis, S. M., Arridge, CS, Lagg, A., Fränz, M., Dougherty, M. K., Dougherty, M., Ip, W.-H., Jones, GH, Krimigis, SM, Roussos, E.   +32 more
core   +1 more source

Simulation of high energy tail of electron distribution function [PDF]

, 2004
P(論文)This report presents Monte Carlo simulations of the electron energy distribution for alow ionized plasma interacting with the F-region neutral gas.
Aso, Takehiko, Sergienko, Timothy, Häggström, Ingemar, Honary, Farideh, Gustavsson, Björn   +4 more
core   +1 more source

Recycling of NiTi Shape Memory Alloys: Fundamental and Technological Aspects of a Vacuum Induction Melting Processing Route

Advanced Engineering Materials, EarlyView.
The present study investigates recycling of NiTi shape memory alloys via vacuum induction melting. An ingot was synthesized from elemental Ni and Ti and subjected to three subsequent remelting cycles. Remelting increases process durations and impurity levels and adversely affects microstructures and functional properties.
Sakia Sophia Noorzayee, Son Tung Mai, Sarath Menon, Braulio Gadiel Sánchez Ortega, Ralf Drautz, Alexander Kauffmann, Gunther Eggeler, Jan Frenzel   +7 more
wiley   +1 more source

Plasmon Excitation in the Interaction of Slow Singly Charged Argon Ions with Magnesium

Solids
We report angle-resolved energy spectra of electron emitted in the interaction of slow singly charged heavy ions with Mg surface. The work is focused mainly on the excitation of plasmons of Mg under Argon impact.
Pierfrancesco Riccardi
doaj   +1 more source