2,261 research outputs found
Response Fibre Bragg Grating (FBG) strain sensors embedded at different locations through the thickness around a delamination in a composite lamina
A few FBG strain sensors were embedded at a vicinity
of delamination of a laminated composite plate.
Reflected spectra of FBG sensors which located in the
same layer as the delamination and one layer above the
delamination were investigated in order to understand the
change of the reflected spectra due to stress
concentrations at the delamination. The reflected
waveforms of sensors were broadened with the increase
of loading, as expected. A considerable difference in
the response of two sensors was observed during both
uniaxial and flexural loading. These differences show
that the FBG sensors are capable of capturing the precise
nature of the delamination under various loading
conditions. Further, these observations provide
evidence of the feasibility of using FBG sensor responses
obtained from various locations allows the location of
the delamination to be determined. This paper details
some new and interesting findings of the use of spectral
shapes and strain measurements from embedded FBG
sensors in damage detection
Comparison of CâC bond hydrogenation in C-4 unsaturated nitriles over Pt/alumina
The hydrogenation of allyl cyanide (but-1-ene-4-nitrile, AC), trans- and cis-crotononitrile (E- and Z-but-2-ene nitrile, TCN and CCN), and methacrylonitrile (2-cyano-1-propene, MCN) were studied, both singly and competitively, over a Pt/alumina catalyst in the liquid phase. Each unsaturated nitrile only underwent CâC bond hydrogenation: no evidence was found for the formation of the saturated or unsaturated amine. The nonconjugated allyl cyanide was found to be the most reactive unsaturated nitrile. Activation energies for the hydrogenation of the CâC bond in AC and MCN were determined giving values of 64 ± 7 kJ molâ1 for AC and 37 ± 4 kJ molâ1 for MCN. The reaction was zero order for both nitriles. Competitive hydrogenations revealed that not only does allyl cyanide react preferentially over the other isomers but also it inhibits the hydrogenation of the other isomers. When all four nitriles were simultaneously hydrogenated, inhibition effects were easily seen suggesting that in terms of strength of bonding to the surface an order of AC > CCN > TCN ⌠MN can be generated
Queering Asexuality: Asexual-Inclusion in Queer Spaces
Discussions about emerging sexual identities are prevalent in todayâs society. As our recognition of the diversity of sexual identities grows, so does our need to define these identities and to better understand how they represent the human experience. One such identity is asexuality, which is defined by the Asexual Visibility and Education Network (AVEN) as a âperson who experiences no sexual attractionâ (âOverviewâ n.d.). In this research, I will analyze the debate over whether asexual individuals should be considered âqueer.â This analysis will examine previous research that focuses on identity, discourse, and boundaries between identities. The goal of this research is to enrich our understanding of how people use language to make identity statements, and to negotiate and navigate boundaries between identities by answering the following questions: 1.) Why might boundaries exist between identities? 2.) How does discourse vary, based on a groupâs status within a conversation? 3.) Why is the conversation surrounding asexual inclusion important
Asexuality and boundaries in online discourse
In this research, I will analyze the ongoing online discussion about whether or not asexuality can or should be considered queer enough to be included in queer spaces. By combining research based in both discourse analysis and queer theory, this paper offers a unique view not only of asexuality\u27s status in contemporary culture, but also of the way language is used to make statements about who belongs and who doesn\u27t, particularly in online spaces. This work will further explore how ideologies affect the formation of, and discourse between, different groups (van Dijk 2006b: 733-734)
Chirping fiber Bragg gratings within additively manufactured polymer packages.
Fiber Bragg gratings are embedded within 3D printed polymer packages. Information about both induced and applied stresses, and operator error, can be determined from the observed spectral shifts and chirping. A novel way to produce packaged broadband gratings, with ÎλBW>7nm/cm, is proposed and demonstrated
Hydrogen Two-Photon Continuum Emission from the Horseshoe Filament in NGC 1275
Far ultraviolet emission has been detected from a knot of Halpha emission in
the Horseshoe filament, far out in the NGC 1275 nebula. The flux detected
relative to the brightness of the Halpha line in the same spatial region is
very close to that expected from Hydrogen two-photon continuum emission in the
particle heating model of Ferland et al. (2009) if reddening internal to the
filaments is taken into account. We find no need to invoke other sources of far
ultraviolet emission such as hot stars or emission lines from CIV in
intermediate temperature gas to explain these data.Comment: 9 pages, 8 figures. Accepted for publication in MNRA
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