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
  • permeability  (3)
  • Korea
  • Springer  (3)
  • American Geophysical Union (AGU)
  • 1990-1994  (3)
Collection
Publisher
  • Springer  (3)
  • American Geophysical Union (AGU)
Years
Year
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Applied composite materials 1 (1994), S. 351-371 
    ISSN: 1573-4897
    Keywords: commingled yarn ; impregnation ; consolidation ; thermoplastics ; processing ; permeability ; mechanical testing ; mathematical modelling ; compression moulding ; glass fibre bed
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Impregnation mechanisms of different kinds of GF/PP commingled yarns have been studied. As the reinforcing fibres were always the same, a global description has been worked out. Two different mathematical approaches for fibre bed permeability (Kozeny-Carman and Gutowski) were compared. The constants of the applied mathematical models have to stay the same if the fibre reeinforcement and the fibre arrangement is the same. Neither the kind of matrix, nor the fibre volume content may change these constants. Differences in the degree of impregnation after the same process conditions can be only due to different sizes of fibre agglomerations, thus the initial distribution of reinforcing fibres and matrix. For an exact determination of impregnation times and conditions the exact distribution of fibres in the intermediate material and after processing has to be known. This distribution is determined by SEM microscopy and data given from the material supplier. The importance of different process parameters, such as temperature, pressure, processing time is weighted by determining the density and mechanical properties of the specimens.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1573-0603
    Keywords: transport ; epithelium ; edema ; beta-agonist ; barrier ; permeability
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary To investigate the cell physiologic and biological properties of the alveolar epithelium, we studied rat alveolar epithelial cell monolayers grown on permeable supports in primary culture. Type II alveolar epithelial cells were disaggregated using elastase, and partially purified on a discontinuous metrizamide gradient. These isolated cells were plated onto tissue culture-treated Nuclepore membrane filters at 1.5×106 cells/cm2 and maintained in a humidified incubator (5% CO2 in air, 37° C). After 2 days in culture, the bathing media on both sides of the cell monolayers were changed to fresh culture medium, thus removing nonadherent cells (mostly leukocytes). These monolayers exhibit a high transmonolayer resistance (〉2000 Ω-cm2) and actively transport ions. Radionuclide flux studies indicate that Na+ is the predominant ionic species absorbed actively under baseline conditions, accounting for about 80% of the total active ion transport. Cl− seems to be passively transported across the epithelium. However, when the epithelium is exposed to a beta-agonist (terbutaline), active absorption of Na+ is increased and active absorption of Cl− occurs. Although it is clear that both active Na+ and Cl− transport are dependent on Na+/K+-ATPase activity, and that Na+ enters cells predominantly through channels, the specific mechanisms by which Cl− enters and exits the alveolar epithelial cells remain unclear. The stimulated reabsorption of Na+ and Cl− may be important in helping to remove excess fluid from alveolar air spaces in the lung.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Pharmaceutical research 9 (1992), S. 1113-1122 
    ISSN: 1573-904X
    Keywords: thyrotropin releasing hormone ; buccal mucosa ; metabolism ; permeability ; in vitro tissue integrity ; transport pathways ; rate-limiting barrier
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The transport of thyrotropin releasing hormone (TRH) in rabbit buccal mucosa in vitro has been investigated with respect to (a) rate and type of metabolism of TRH on mucosal and serosal sides of buccal mucosa, (b) mechanism of TRH transport including charge effect on its permeability, and (c) pathway and rate-limiting regions of TRH movement. In addition, the integrity of excised buccal mucosa has been evaluated for purposes of in vitro solute diffusion experiments using tissue ATP level data, transmission electron microscopy, and TRH transport kinetic data. The results indicate that excised rabbit buccal mucosa can be used for TRH diffusion studies for approximately 6 hr. In addition, TRH apparently traverses buccal mucosa by simple diffusion with a steady-state permeability of about 10−7 cm/sec, and this permeability is independent of pH. Moreover, the primary pathway appears to be via the intercellular space in the rate-limiting barrier, i.e., the upper 50 µm of the epithelium. Finally, TRH is degraded predominantly by deamidase activity, which is followed by, to a lesser degree, carboxypeptidase metabolism.
    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...