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
  • 1980-1984  (3)
  • 1965-1969
  • 1983  (2)
  • 1982  (1)
  • 1
    Electronic Resource
    Electronic Resource
    13C- and Na-NMR studies of sodium octanoate in reversed micelles (1983)
    Springer
    Colloid & polymer science 261 (1983), S. 340-345 
    Details
    ISSN: 1435-1536
    Keywords: reversed micelles ; sodium octanoate ; 1-hexanol ; 13C-NMR ; Na-NMR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The dynamic behavior of sodium octanoate (NaO), especially that of the polar headgroups of NaO, in1-hexanol in the presence of cosolubilized water was studied by Na-NMR and13C-NMR at 24 and 25 MHz. Na-NMR data have indicated that the mobility of the sodium ions of NaO shows the lowest value at 1.2 M of NaO at a given water content, which is related to the maximum amount of water cosolubilized into the system and the change in the structure of polar headgroups of NaO.13C-NMR data have shown that the mobility of methylene carbons, No. 5 and 6 of NaO, is higher than that of methylene carbons, No. 4 and 7, and that water molecules entered among the polar headgroups of NaO affect the mobility of methylene carbons of NaO, No. 5 and 6. The hydroxyl groups of1-hexanol were found to be contact with water molecules entered among the polar headgroups of NaO, and to fill the space among the hydrocarbon chains of NaO. By assuming spherical geometry the size of water pools and the average aggregation number were calculated, and the results were discussed on the basis of13C-NMR and Na-NMR data.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01413941
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Determination of pH in reversed micelles (1982)
    Springer
    Colloid & polymer science 260 (1982), S. 697-701 
    Details
    ISSN: 1435-1536
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The pH in the reversed micellar system of di(ethylhexyl) sodium sulfosuccinate (Aerosol OT, AOT) / phosphate buffer solutions/octane was determined by a P-NMR technique, and pHs in the reversed micelles containing buffer solutions other than the phosphate buffer solution were measured by the spectrophotometric method with the aid of Phenol Red. pHs in reversed micelles were found to be substantially determined by the buffer capacity of buffer solutions solubilized into the systems. By means of both the methods, pKa of Phenol Red in the systems was found to be 7.7, which is almost consistent with that in water. Analysis of Na-NMR spectra indicates that the mobility of the sodium ion of AOT is independent of the molar ratio of water to AOT when the ratio is above 7 and is restricted strongly by the interaction with the sulfonate group of AOT. The relationship between pH and the mobility of the sodium ion was discussed on the basis of the data of Na-NMR spectra.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01414656
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Conformational studies of copoly (N 5-ω-hydroxyalkyl-L-glutamine-L-glutamic acid)s (1983)
    Springer
    Colloid & polymer science 261 (1983), S. 591-599 
    Details
    ISSN: 1435-1536
    Keywords: Copoly (N 5-ω-hydroxyalkyl-L-glutamine-L-glutamic acid) ; Solvent-induced conformational change ; pH-induced conformational change
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Copoly (α-amino acid)s consisting ofL-glutamic acid residue andN 5-ω hydroxyalkyl-L-glutamine residue, i.e., 2-hydroxyethyl, 3-hydroxypropyl, and di-2-hydroxyethyl derivatives were prepared by the reactions of copoly (L-glutamic acid) containing succinimide ester with corresponding amino alcohols. The conformation of these copolymers was examined by the CD and infrared measurements. These three copolymers containing about 20–30% hydroxyalkyl groups undergo a methanol-induced and a pH-induced conformational transitions. The copolymer containing about 50% 3-hydroxypropyl group assumes the α-helical conformation in the pH region from 2.5 to 11.6, and in a methanol-water mixture (9∶1). On the other hand, the copolymer containing about 60% di-2-hydroxyethyl groups does not allow any helical conformation even at lower pH and also even in a trifluoroethanol-water mixture (9∶1), suggesting that the branched hydroxyalkyl group is unfavorable for the formation of α-helix. Furthermore, the poly(N 5-di-2-hydroxyethyl-L-glutamine) is shown to have a rather disordered structure in the solid state.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01526625
    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...