ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

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
    Characterization of microporous-mesoporous MCM-41 silicates prepared in the presence of octyltrimethylammonium bromide (1997)
    Springer
    Catalysis letters 49 (1997), S. 147-153 
    Details
    ISSN: 1572-879X
    Keywords: MCM-41 ; M41S ; mesoporous materials ; bimodal pore size distribution ; thermal restructuring
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract MCM-41 silicates prepared in the presence of octyltrimethylammonium bromide either by a conventional method or by post-synthesis hydrothermal treatment were characterized by nitrogen adsorption in a wide range of relative pressure from 10-6 to 1. Hydrothermally restructured samples were found to have lower BET surface areas, lower external surface areas and thicker silica walls than the non-treated sample. More importantly, in addition to their characteristic mesopores (ca. 3 nm), they were shown to have considerable amounts of micropores. The relative amount of micropores and mesopores was shown to be dependent on the treatment conditions. Thus, it is demonstrated that the postsynthesis hydrothermal restructuring is a convenient synthesis route to MCM-41 silicates with bimodal pore size distribution involving controllable amounts of microporosity.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1019073809368
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Adsorption and Thermogravimetric Methods for Monitoring Surface and Structural Changes in Ordered Mesoporous Silicas Induced by their Chemical Modification (1999)
    Springer
    Adsorption 5 (1999), S. 313-317 
    Details
    ISSN: 1572-8757
    Keywords: MCM-41 ; bonding of organosilanes ; surface analysis ; adsorption energy distribution ; pore structure analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Physics , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract The current work demonstrates that the standard adsorption analysis has a limited applicability for characterization of chemically modified porous silicas. Since low-pressure nitrogen adsorption isotherms are sensitive to the surface changes caused by chemical modification of silicas, these isotherms were successfully used to evaluate their surface heterogeneity during different stages of modification. The surface analysis was accomplished by using adsorption energy distributions and high-resolution comparative plots.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1008992228421
    Location Call Number Expected 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...