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
Filter
  • Articles: DFG German National Licenses  (3)
  • 1990-1994  (3)
  • Polymer and Materials Science  (2)
  • 36.40. + d  (1)
Source
  • Articles: DFG German National Licenses  (3)
Material
Years
Year
Keywords
  • 1
    Electronic Resource
    Electronic Resource
    Kinetics of photo-induced dissociation of Na clusters deposited on Mica (1993)
    Springer
    The European physical journal 28 (1993), S. 321-329 
    Details
    ISSN: 1434-6079
    Keywords: 36.40. + d ; 32.80.Wr ; 33.80.Gj
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Na clusters bound to mica surfaces have been irradiated with pulsed and cw visible laser light. Kinetic energy and angular distributions of the Na atoms desorbing from the clusters have been determined using cw two-photon laser-induced fluorescence detection. In addition the dependence of the desorption rate on laser power, wavelength and polarization has been measured. The most probable kinetic energyE kin of the photodesorbed atoms at the surface temperatureT S =300 K was found to beE kin=18±5 meV, independent of laser irradiance (3 µJ/cm2...20 mJ/cm2) and wavelength (450 nm, 505 nm, 658 nm). With increasing orientation angle between detection axis and surface normal (0°≦Θ≦90°)E kin was observed to decrease slightly, while it was nearly independent of surface temperature betweenT S =30 K andT S =300 K. Also, with increasing radius of the Na clusters the desorbing Na atoms slowed down. The angular distribution of the Na atoms was of cos2-type with respect to the surface normal. These observations suggest that laser-induced desorption of Na from Na clusters bound to mica surfaces involves an initial rate-limiting step of direct surface plasmon excitation followed by a final step of delayed thermal desorption.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01437267
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Untersuchungen zur Bildung wasserlöslicher Cellulosephosphate durch homogene Acylierung im System Cellulose N2O4/DMF. 1. Mitt.: Problemstellung und Ergebnisse zur Acylierung mit POCl3 (1991)
    Weinheim : Wiley-Blackwell
    Acta Polymerica 42 (1991), S. 213-217 
    Details
    ISSN: 0323-7648
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: After dissolution in the N2O4/DMF-system resulting in a partial substitution of OH-groups by nitrite ester groups, cellulose has been phosphorylated at homogeneous conditions of reaction with POCl3 to DSp-values up to about 1 in the presence of triethylamine. Solubility of the products in water was found in the DSp-range between 0.3 and 0.6 after suitable treatment of the reaction product in a protic medium.
    Notes: Nach Auflösung in einem N2O4/DMF-Gemisch unter partieller Bildung des Nitritesters wurde Cellulose unter homogenen Reaktionsbedingungen mit POCl3 in Gegenwart von Triethylamin bis zu DSp-Werten von etwa 1 phosphoryliert. Wasserlösliche Produkte wurden im DSp-Bereich zwischen 0,3 und 0,6 nach einer Behandlung des Reaktionsproduktes in einem protischen Medium erhalten.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/actp.1991.010420506
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Untersuchungen zur Bildung wasserlöslicher Cellulosephosphate durch homogene Acylierung im System Cellulose/N2O4/DMF. 2. Mitt.: Ergebnisse zur Acylierung mit Derivaten des POCl3 und zusamenfassende Diskussion zum Ablauf der Phosphorylierung im System N2O4/DMF/Cellulose1. Mitt.: siehe [1] (1991)
    Weinheim : Wiley-Blackwell
    Acta Polymerica 42 (1991), S. 554-560 
    Details
    ISSN: 0323-7648
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Cellulose and carboxymethyl cellulose are phosphorylated after dissolution in the N2O4/DMF-system by employing a modified acylation agent prepared by reaction of POCl3 with H2O and with N2O4, respectively. The N2O4-modified reagent was found to be suitable for preparing water-soluble cellulsoe phosphates in the Na+ and the triethylammonium salt form in a DS-range between 0.2 and 1.3. A reaction mechanism taking into account the steps of acylation and after-treatment is discussed.
    Notes: Cellulose und Carboxymethylcellulose wurden nach Auflösung im N2O4/DMF-System mit modifizierten Phosphorylierungs-reagentien acyliert, die durch Umsetzung von POCl3 mit Wasser oder mit N2O4 erhalten wurden. Das durch Umsetzung mit N2O4 modifizierte Reagens erwies sich als geeignet zur Gewinnung wasserlöslicher Cellulosephosphate in Form des Natrium-oder des Triethylammoniumsalzes im DS-Bereich zwischen 0,2 und 1,3. Ein Reaktionsmechnaismus für die bei Acylierung und Nachbehandlung ablaufenden Umsetzungen wird diskutiert.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/actp.1991.010421105
    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...