ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • 78.47. + p  (1)
  • Analytical Chemistry and Spectroscopy  (1)
  • 1995-1999  (2)
Collection
Keywords
Publisher
Years
Year
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Applied physics 63 (1996), S. 255-264 
    ISSN: 1432-0649
    Keywords: 07.60.Ly ; 42.65.Re ; 78.47. + p
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract A femtosecond frequency-domain interferometer is applied to metal-free and vanadyl phthalocyanine (H2Pc and VOPc) thin films to measure time-resolved difference phase and transmission spectra simultaneously. For both samples, the phase-change dynamics is different from the transmission-change dynamics at 620 nm, reflecting that the phthalocyanines (Pc) cannot be modeled with a two-level system but by a multi-level or inhomogeneously broadened system, in which each level pair exhibits different relaxation dynamics. Because of this dynamical difference, a phase-change measurement is required to correct distortion of the transient spectra due to induced phase modulation of probe pulses. Near zero time delay, the phase and transmission changes show different growth behavior. This behavior is explained by antisymmetric amplitude and phase gratings which are produced by coherent coupling between frequency-chirped pump and probe pulses.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1075-4261
    Keywords: brain microsomal membranes ; fatty acids ; learning behavior ; FTIR ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Physics
    Notes: We measured the Fourier transform infrared spectra of brain microsomal membranes prepared from rats fed under two dietary oil conditions with and without brightness-discrimination learning tasks: one group fed α-linolenate deficient oil (safflower oil) and the other group fed the sufficient oil (perilla oil) from mothers to offspring. The infrared spectra of microsomes under the two dietary conditions without the learning task showed no significant difference in the range 1000-3000 cm-1. Only after the learning task were the infrared spectral differences noted between the microsomal membranes from both groups. Spectral differences were observed mainly in the absorption bands of fatty acid ester at around 1730 cm-1 (sn-2 position), those of phosphate and oligosaccharides in the range of 1050-1100 cm-1, and a band at around 1145 cm-1. The infrared band of fatty acid ester at the sn-2 position in the microsomal membrane shifted to a longer wavenumber position in the perilla oil group than in the safflower oil group, suggesting a difference between both groups in hydrogen bonding of the fatty acid ester with water. A band observed at 1055 cm-1 and a small band at around 1145 cm-1 in the second derivative spectrum decreased in intensity in the perilla oil group after learning task. These bands were assigned mainly to the oligosaccharide C - O bond in hydroxyl groups that might interact with some other membrane components. These results suggest changes in hydration of membrane surface and modification in oligosaccharide environment (removal or modification) of microsomes, which may be correlated in part with dietary oil-induced changes in learning performance. © 1997 John Wiley & Sons, Inc. Biospectroscopy 3: 281-290, 1997
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...