Institution
Wright-Patterson Air Force Base
Other•Wright-Patterson AFB, Ohio, United States•
About: Wright-Patterson Air Force Base is a other organization based out in Wright-Patterson AFB, Ohio, United States. It is known for research contribution in the topics: Laser & Microstructure. The organization has 5817 authors who have published 9157 publications receiving 292559 citations. The organization is also known as: Wright-Patterson AFB & FFO.
Topics: Laser, Microstructure, Thin film, Mach number, Liquid crystal
Papers published on a yearly basis
Papers
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TL;DR: In this paper, the impact of polymer backbone rigidity on the photomechanical response in a series of linear, azobenzene-functionalized polymers was examined, and it was shown that increasing the rigidity of the polymer backbone increases the magnitude of stress that is generated but decreases the angle of cantilever deflection.
Abstract: Azobenzene-functionalized polyimide materials can directly transduce light into mechanical force. Here, we examine the impact of polymer backbone rigidity on the photomechanical response in a series of linear, azobenzene-functionalized polymers. The rigidity of the backbone was varied by the polymerization of five dianhydride monomers with a newly synthesized diamine (azoBPA-diamine). The azobenzene-functionalized linear polymers exhibit glass transition temperatures (Tg) ranging from 276 to 307 °C and maintain excellent thermal stability. The photomechanical response of these materials was characterized by photoinduced cantilever bending as well as direct measurement of photogenerated stress upon exposure to linearly polarized, 445 nm light. Increasing the rigidity of the polymer backbone increases the magnitude of stress that is generated but decreases the angle of cantilever deflection.
81 citations
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TL;DR: It is reported that in situ polymerization of a highly conductive self-doped conducting polymer "skin" around and along single stranded DNA dispersed and functionalized single wall carbon nanotubes can greatly decrease the contact resistance.
Abstract: The overall conductivity of SWNT networks is dominated by the existence of high resistance and tunneling/Schottky barriers at the intertube junctions in the network. Here we report that in situ polymerization of a highly conductive self-doped conducting polymer “skin” around and along single stranded DNA dispersed and functionalized single wall carbon nanotubes can greatly decrease the contact resistance. The polymer skin also acts as “conductive glue” effectively assembling the SWNTs into a conductive network, which decreases the amount of SWNTs needed to reach the high conductive regime of the network. The conductance of the composite network after the percolation threshold can be 2 orders of magnitude higher than the network formed from SWNTs alone.
80 citations
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TL;DR: In this paper, an integrated modeling/simulation and experimental approach was employed to represent the nonlinear constitutive behavior under both LSP and thermal loads, and the activation enthalpy of the relaxation process for laser shock peened Ti-6Al-4V was determined to be in the range of 0.71 eV to 1.37 eV.
Abstract: Laser shock peening (LSP) induced residual stresses in Ti–6Al–4V, and their thermal relaxation due to short-term exposure at elevated temperatures are investigated by an integrated modeling/simulation and experimental approach. A rate and temperature-dependent plasticity model in the form of Johnson–Cook (JC) has been employed to represent the nonlinear constitutive behavior under both LSP and thermal loads. By comparing the simulation results with experimental data, model parameters for Ti–6Al–4V are first calibrated and subsequently applied in analyzing the thermal stability of the residual stress in LSP-treated Ti–6Al–4V. The analysis shows that the magnitude of stress relaxation increases with the increase of applied temperature due to material softening. Most of stress relaxation occurs before 10 min to 20 min exposure in this study, and stress distribution becomes more uniform after thermal exposure. An analytical model based on the Zener–Wert–Avrami formula is then developed based on the simulation results. The activation enthalpy of the relaxation process for laser shock peened Ti–6Al–4V is determined to be in the range of 0.71 eV to 1.37 eV.
80 citations
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TL;DR: A vinylene-linked porphyrin dimer, with no substituents at the beta-positions, has been synthesized by CuI/CsF promoted Stille coupling, and the absorption, emission spectra, and electrochemistry reveal substantial porphirin-porphyrin pi-conjugation.
80 citations
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TL;DR: In this article, the residual stresses in laser shock peened (LSP) Inconel 718 Ni-base superalloy and their thermal relaxation behavior were investigated based on three-dimensional nonlinear finite element analysis.
80 citations
Authors
Showing all 5825 results
Name | H-index | Papers | Citations |
---|---|---|---|
John A. Rogers | 177 | 1341 | 127390 |
Liming Dai | 141 | 781 | 82937 |
Mark C. Hersam | 107 | 659 | 46813 |
Gareth H. McKinley | 97 | 467 | 34624 |
Robert E. Cohen | 91 | 412 | 32494 |
Michael F. Rubner | 87 | 301 | 29369 |
Howard E. Katz | 87 | 475 | 27991 |
Melvin E. Andersen | 83 | 517 | 26856 |
Eric A. Stach | 81 | 565 | 42589 |
Harry L. Anderson | 80 | 396 | 22221 |
Christopher K. Ober | 80 | 631 | 29517 |
Vladimir V. Tsukruk | 79 | 481 | 28151 |
David C. Look | 78 | 526 | 28666 |
Richard A. Vaia | 76 | 324 | 25387 |
Kirk S. Schanze | 73 | 512 | 19118 |