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
Filter
  • 1965-1969  (4)
Collection
Keywords
Publisher
Years
Year
  • 1
    Electronic Resource
    Electronic Resource
    Specific heat studies of various wool-water systems (1968)
    New York : Wiley-Blackwell
    Biopolymers 6 (1968), S. 1355-1377 
    Details
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Measurements of specific heat of wool-water systems were made at approximately 5°C intervals over the temperature range -70 to 100°C. Ten different, samples were used, each with a different amount of absorbed water in the range from dry ness to saturation at 0°C. The graph of specific heat against temperature for dry wool is precisely linear over the complete temperature range, suggesting that thermal motion is entirely vibrational. When absorbed water is present the data can be conveniently discussed in terms of behavior below and above an amount of absorbed water of 22.7 g in 100 g of wool (22.7% of absorbed water). Below 22.7% there is only one temperature range in which the results indicate an appreciable transition in heat absorbing properties. The temperature of transition depends on water content but is higher than 0°C. Above 22.7% a second transition appears in the range -30 to 0°C and grows rapidly larger with increase of water content. The first transition is tentatively ascribed to a slightly cooperative breakdown of polar bonds in wool, and the second to a process analogous to melting in the absorbed water. The results are discussed in these terms as well as with reference to specific heat theories, the heat absorption of the wool component and the water component, and enthalpy differences between the various samples.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bip.1968.360060910
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Heats of fusion of various amounts of absorbed water in wool keratin (1969)
    New York : Wiley-Blackwell
    Biopolymers 7 (1969), S. 459-474 
    Details
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Wool-water systems, at water contents above a threshold value of 22.7 g of water per 100 g of wool keratin, yielded curves of specific heat against temperature showing peaks that are ascribed to the fusion of the absorbed water. Integral and incremental heats of fusion were obtained. Integral heats increase as the square of the water content above the threshold, and incremental heats follow a linear relationship. The incremental heat reaches a value of 55 cal/absorbed water, at the saturation water content, at 0°C of 33.9 g of water per 100 g of keratin. The state of the absorbed water is discussed. Clustering of water molecules takes place only above the threshold water content.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bip.1969.360070405
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Specific heat of wool in the temperature range -50 to 100°C (1965)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 9 (1965), S. 893-902 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: The specific heat of wool containing 2.6, 2.9, and 8.9 g. of water per 100 g. 01 dry wool has been measured over the temperature range -50 to 100°C. All of the wool samples showed an approximately linear increase of cp, with temperature, but small increments appeared at -30, 20, 50, and 70°C. With increasing water content at any one temperature the specific heat increased. The specific heat of the sorbed water seemed to be more nearly like that of ice than of liquid water; if the sorbed water is assumed to have the specific heat of ice a t all compositions and temperatures, an apparent specific heat of the wool can be calculated. With increasing water content the apparent specific heat of the wool approaches that of the synthetic polymer, nylon 6.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1965.070090307
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Energetic and entropic components of tension in elastomeric wool fibers (1965)
    New York : Wiley-Blackwell
    Journal of Polymer Science Part A: General Papers 3 (1965), S. 3331-3342 
    Details
    ISSN: 0449-2951
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Tension against temperature data were obtained for both unreduced wool fibers and fibers in which some of the disulfide bonds had been reduced by a thiol. The measurements were done while the fibers contained a diluent. Coefficients of volume thermal expansion were also measured. From the results the ratio of the energetic component of tension to the total tension (fe/f) was calculated. Most values of fe/f were within the range ± 0.20. In the case of unreduced wool fe/f changed from negative to positive as the extension increased. With a reduced sample containing 8% of the native disulfide, fe/f was negative and nearly constant over the range of extension employed. The change for unreduced wool follows from extension-dependent interactions between polypeptide chains. The results indicate that, for unperturbed polypeptide chains from wool taken into solution following disulfide reduction, the end-to-end distance will decrease with increase of temperature, a partially extended form being the lower energy state.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1965.100030925
    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...