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What is the modulus of elasticity of bone?
The average trabecular Young’s modulus measured ultrasonically and mechanically was 14.8 GPa (S.D. 1.4) and 10.4 (S.D. 3.5) and the average Young’s modulus of microspecimens of cortical bone measured ultrasonically and mechanically was 20.7 GPa (S.D.
How do you increase the modulus of hydrogel?
For instance, increasing the crystallinity of the polymer chains within the hydrogel by the addition of a salt or base solution at high concentration can enhance the modulus of the hydrogel.
How do you measure the elastic modulus of a hydrogel?
On a mesoscale, the elastic modulus can be measured by the imaging-based indentation methods which measure the indentation depth of a hydrogel sample deformed by a static ball indenter on the gel. The measured indentation depth is converted to the Young’s modulus of the hydrogel via a contact mechanics model.
How is hydrogel stiffness measured?
You can meaure the stiffness of your hydrogels by performing oscillatory rheological measurements of the elastic modulus G΄ and the viscous modulus G΄΄ as function of shear strain (Amplitude sweep experiment) and as function of frequency (Frequency sweep experiment).
How do hydrogels swell?
Hydrogels made of polyelectrolytes serve as pH-sensitive sensors (Peppas et al., 2000). Depending on solution pH and dissociation constants (pKa or pKb) of polymer side groups, the hydrogel becomes ionized and swells as a result of electrostatic repulsion of polymer chains (see Fig.
Does hydrogel dissolve in water?
A hydrogel is a crosslinked hydrophilic polymer that does not dissolve in water.
What is the elastic modulus of gelatin?
=39.3kPa
G´ remains constant in the 0.01 to 100 Hz range with an average value of 13.1kPa. Hence, the elastic modulus arisen from rheology experiments is E=39.3kPa, which practically coincides with the obtained in uniaxial compression.
What is the Young’s modulus of Jello?
So, the Young’s Modulus of double-strength Jell-O is about 5.3 psi and 4.3 psi for the double-strength generic gelatin for moderate strains. That Young’s Modulus is about a million times lower than the modulus of shale, which is typically a few millions of psi!
How do you measure AFM stiffness?
The basic principle of this method is to indent a cell with an AFM tip of selected geometry and measure the applied force from the bending of the AFM cantilever. Fitting the force-indentation curve to the Hertz model for the corresponding tip geometry can give quantitative measurements of material stiffness.
How do you test the mechanical properties of hydrogel?
At present the most commonly used method to determine the mechanical properties of hydrogels are by tensile testing or strip extensiometry. These methods have been extensively used to study the mechanical behaviour of various hydrogels [13, 15].