Characteristic Vibrational Spectral Change Observed for the π-Conjugated Structure of Sulfonated Polyethylene

1997 ◽  
Vol 30 (10) ◽  
pp. 2956-2962 ◽  
Author(s):  
Kohji Tashiro ◽  
Takeru Kitashoji ◽  
Jyoji Ihata
Keyword(s):  
Spectral Change

scholarly journals Spectral change of hadrons and chiral symmetry

2002 ◽  
Vol 698 (1-4) ◽  
pp. 243-252 ◽  
Author(s):  
T. Hatsuda
Keyword(s):  
Chiral Symmetry ◽  
Spectral Change

Temperature Gradients Through EHD Films and Molecular Alignment Evidenced By Infrared Spectroscopy

1981 ◽  
Vol 103 (1) ◽  
pp. 65-73 ◽  
Author(s):  
V. W. King ◽  
J. L. Lauer
Keyword(s):  
Absorption Spectrum ◽  
Emission Spectra ◽  
Infrared Emission ◽  
Molecular Alignment ◽  
Temperature Gradients ◽  
Spectral Change ◽  
Continuum Source ◽  
Polyphenyl Ether ◽  
Elementary Analysis ◽  
Gap Width

Partial and complete emission band reversals have been observed in the infrared emission spectra from portions of operating sliding contacts. An elementary analysis has been carried out to show that partial reversals are due to temperature gradients in the fluid film—the film acts both as a radiation-emitter and absorber, and that total reversals—an emission spectrum appears as an absorption spectrum—are likely to be due to a continuum source, such as hot solid asperities. The total energy radiated under the latter conditions exceeds that under the others. A decrease in gap width with increased load was accompanied by a dramatic spectral change in the case of 5P4E polyphenyl ether, which is indicative of molecular alignment.

Photo-induced reversible spectral change in several AgI–oxide particle composites

2006 ◽  
Vol 376-377 ◽  
pp. 827-830 ◽  
Author(s):  
Fumito Fujishiro ◽  
Shosuke Mochizuki
Keyword(s):  
Oxide Particle ◽  
Spectral Change

scholarly journals Sensitivity of rat inferior colliculus neurons to frequency distributions

2015 ◽  
Vol 114 (5) ◽  
pp. 2941-2954 ◽  
Author(s):  
Björn Herrmann ◽  
Aravindakshan Parthasarathy ◽  
Emily X. Han ◽  
Jonas Obleser ◽  
Edward L. Bartlett
Keyword(s):  
Inferior Colliculus ◽  
Field Potentials ◽  
Spectral Change ◽  
Relative Probability ◽  
Frequency Distributions ◽  
Specific Adaptation ◽  
Spectral Changes ◽  
Neural Spiking ◽  
Different Response ◽  
Neural Gain

Stimulus-specific adaptation refers to a neural response reduction to a repeated stimulus that does not generalize to other stimuli. However, stimulus-specific adaptation appears to be influenced by additional factors. For example, the statistical distribution of tone frequencies has recently been shown to dynamically alter stimulus-specific adaptation in human auditory cortex. The present study investigated whether statistical stimulus distributions also affect stimulus-specific adaptation at an earlier stage of the auditory hierarchy. Neural spiking activity and local field potentials were recorded from inferior colliculus neurons of rats while tones were presented in oddball sequences that formed two different statistical contexts. Each sequence consisted of a repeatedly presented tone (standard) and three rare deviants of different magnitudes (small, moderate, large spectral change). The critical manipulation was the relative probability with which large spectral changes occurred. In one context the probability was high (relative to all deviants), while it was low in the other context. We observed larger responses for deviants compared with standards, confirming previous reports of increased response adaptation for frequently presented tones. Importantly, the statistical context in which tones were presented strongly modulated stimulus-specific adaptation. Physically and probabilistically identical stimuli (moderate deviants) in the two statistical contexts elicited different response magnitudes consistent with neural gain changes and thus neural sensitivity adjustments induced by the spectral range of a stimulus distribution. The data show that already at the level of the inferior colliculus stimulus-specific adaptation is dynamically altered by the statistical context in which stimuli occur.

Nuclear Magnetic Resonance Study of Ring Inversion in Cycloheptene

1971 ◽  
Vol 49 (8) ◽  
pp. 1256-1261 ◽  
Author(s):  
Maurice St-Jacques ◽  
Cambyse Vaziri
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Nuclear Magnetic Resonance Study ◽  
Spectral Change ◽  
Magnetic Resonance Study ◽  
Ring Inversion ◽  
Energy Profiles ◽  
Nuclear Magnetic

The p.m.r. spectrum of 4,4,5,6,6-pentadeuteriocycloheptene (3) has been studied down to −171 °C. Analysis of the spectral change below −160 °C yielded a ΔF≠ value of 5.0 kcal/mol at −165 °C. Possible energy profiles for the ring inversion of cycloheptene are discussed.

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