(Fourier transform mechanical spectroscopy (FTMS )
The evolution of visco-elastic properties in non-Newtonian fluids exhibiting
time-dependent rheological changes is a matter of wide scientific interest,
particularly so in systems undergoing gelation. The gel-point, where a threedimensional
network structure is established, may be identified rheologically
by the establishment of a characteristic frequency dependence of the dynamic
moduli, and an associated frequency independent loss tangent [Winter and
. [Chambon, 1986
This criterion for gel-point detection, and the non-equilibrium nature of
systems undergoing gelation, requires that data be obtained rapidly over a wide
range of frequency, prompting the development of a frequency multi-plexing
technique known as Fourier Transform Mechanical Spectroscopy, FTMS,
at several frequencies simultane-ously,which allows the measurement of G
. [rather than consecutively, as in a conventional test [Holly et al., 1988
The technique, initially developed to measure visco-elastic properties in the
curing of polymers [Malkin et al., 1984], has been applied to gels (In and
Prud’homme, 1993) and model visco-elastic fluids [Davies and Jones, 1994].
In a variation of the technique, dynamic mechanical properties are determined
using the Fourier transform of pulsed deformations [Vratsanos and Farris,
.[1988
المادة المعروضة اعلاه هي مدخل الى المحاضرة المرفوعة بواسطة استاذ(ة) المادة . وقد تبدو لك غير متكاملة . حيث يضع استاذ المادة في بعض الاحيان فقط الجزء الاول من المحاضرة من اجل الاطلاع على ما ستقوم بتحميله لاحقا . في نظام التعليم الالكتروني نوفر هذه الخدمة لكي نبقيك على اطلاع حول محتوى الملف الذي ستقوم بتحميله .
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