Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Mechanisms of a remanent optical alignment of dyes in a gel matrix (1996)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 80 (1996), S. 4655-4659 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We present the mechanisms of a remanent alignment of polarizable molecules dispersed in a solid silica gel matrix, when submitted to powerful, femtosecond, linearly polarized, optical pulses emitted from a dye laser. This alignment can be related to third-order nonlinearities of the dopants through an orientational optical Kerr effect. Its remanence results from the strong interactions the dopants share with their host matrix, particularly through hydrogen bonds. We expose here the detailed mechanism of this phenomenon, considering that such a rotation of large chromophores may not be compatible at first sight with subpicosecond pulse durations. Through several experiments, we show that this apparent contradiction is solved once analyzed, by the structure of the excitation pulses, which cannot be simply described as "femtosecond pulses'', but consist of two temporal components—a femtosecond one and a nanosecond one—playing different but essential roles in the process. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.363425
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Azo oxide gels for optical storage (1993)
    s.l. : American Chemical Society
    Chemistry of materials 5 (1993), S. 589-591 
    Details
    ISSN: 1520-5002
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/cm00029a001
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Reverse saturable absorption in solid xerogel matrices (1993)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 62 (1993), S. 1721-1723 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Aluminophthalocyanine (APC) and fullerene carbon 60 (C60) have been studied encaged in different silica matrices. The reverse saturable absorption properties of these doped xerogels have been compared to those of reference solutions of APC and C60. We show that reverse saturable absorber molecules retain their properties even when they are enclosed in the pores of a solid xerogel matrix.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.109585
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Modified sol-gel films for optical storage (1994)
    Springer
    Journal of sol gel science and technology 2 (1994), S. 779-782 
    Details
    ISSN: 1573-4846
    Keywords: azooxide gel ; photoisomerization ; birefringence ; functionalized alkoxide
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Substituted azobenzene molecules (DR1, DO3, DR17, DY7, Magneson1, DR19C1 and DR19CICI) are grafted onto a silicon alkoxide precursor. Films are prepared by the sol-gel process. We have conducted preliminary optical experiments with DR1 and DO3 functionalized oxide gels. Optical information is written on the sol-gel film via the trans-cis-trans photoisomerization process with a polarized argon laser beam and read with a low power He-Ne laser. A stable signal (up to 60% of the maximum birefringence) is read a long time after the writing beam had been turned off. This shows the ability of the azo oxide gels to store optical information.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00486349
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Biological activity of functionalized SiO2 thin films prepared by sol-gel method (1996)
    Springer
    Journal of sol gel science and technology 7 (1996), S. 81-85 
    Details
    ISSN: 1573-4846
    Keywords: sol-gel ; functionalized films ; grafting of antibodies ; biological activity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract In this work we investigated the biological properties of sol-gel films in aqueous medium. Functionalized silica films were prepared by the sol-gel process, from organically modified silicon alkoxides with amino or thiol groups. Covalent binding of proteins with different orientations according to the hydrophilic or hydrophobic character of the surface was studied. This binding occurred via a covalent coupling agent providing a very stable linkage. No denaturation was detected and a good detection of the antigen was observed. Immunoassays have demonstrated the biological activity of grafted antibodies.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00401887
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Optical Alignment of Organic Dopants in a Solid Gel Matrix: Dispersed and Grafted Rhodamine B Molecules (1997)
    Springer
    Journal of sol gel science and technology 9 (1997), S. 33-39 
    Details
    ISSN: 1573-4846
    Keywords: dye-doped xerogels ; grafting ; alignment ; optical Kerr effect ; memory
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract We study herein the rotational mobility of organic dye molecules and their ability to align on a strong optical electric field when they are encaged in the pores of an inorganic silica xerogel matrix. We compare the case of dye molecules simply dispersed in the pores of the gel—and possibly held by hydrogen bonds—to the case of molecules chemically grafted on the inner surface of these pores through covalent bonds. The study is led on hybrid silicon-zirconium based inorganic matrices doped with organic rhodamine B molecules. The stronger holding of the dopants when these are grafted to the matrix enhances the molecular alignment—and thus the induced anisotropy—as well as the remanence of this alignment. Furthermore, we show that submitting the samples to a supplementary drying at higher temperature tends to increase both the alignment anisotropy and its stability. We explain these results in terms of mobility of the molecules, in relation to their immediate environment.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1026456222574
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Optical alignment of organic dopants in a solid gel matrix: dispersed and grafted rhodamine B molecules (1997)
    Springer
    Journal of sol gel science and technology 9 (1997), S. 33-39 
    Details
    ISSN: 1573-4846
    Keywords: dye-doped xerogels ; grafting ; alignment ; optical Kerr effect ; memory effect
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract We study herein the rotational mobility of organic dye molecules and their ability to align on a strong optical electric field when they are encaged in the pores of an inorganic silica xerogel matrix. We compare the case of dye molecules simply disperesed in the pores of the gel—and possibly held by hydrogen bonds—to the case of molecules chemically grafted on the inner surface of these pores through covalent bonds. The study is led on hybrid silicon-zirconium based inorganic matrices doped with organic rhodamine B molecules. The stronger holding of the dopants when these are grafted to the matrix enhances the molecular alignment—and thus the induced anisotropy—as well as the remanence of this alignment. Furthermore, we show that submitting the samples to a supplementary drying at higher temperature tends to increase both the alignment anisotropy and its stability. We explain these results in terms of mobility of the molecules, in relation to their immediate environment.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02439334
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Covalent grafting of optically active molecules on silica gels (1997)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 43 (1997), S. 2820-2826 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Active organic molecules are grafted on the xerogel silica matrix by using functionalized alkoxides f-R′-Si(OEt)3, where f is a chemical function and R′ is an alkyl spacer to limit the degrees of freedom of the molecules. Organic-inorganic hybrid films are prepared in which optically nonlinear DRl chromophores are covalently bound to the silica network. These films exhibit a large and stable second-order nonlinear coefficient from second harmonic generation experiments. Protoporphyrin molecules are attached double covalently to the xerogel matrix via flexible organic spacers. Persistent spectral holes are still burnt with moderate fluency at 120 K.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690431329
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...