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Volume shrinking

Explicit forms for the stress tensors d1 are deduced from the microscopic expressions for the component stress tensors and from the scheme of the total stress devision between the components [164]. Within this model almost all essential features of the viscoelastic phase separation observable experimentally can be reproduced [165] (see Fig. 20) existence of a frozen period after the quench nucleation of the less viscous phase in a droplet pattern the volume shrinking of the more viscous phase transient formation of the bicontinuous network structure phase inversion in the final stage. [Pg.185]

Let us assume a many-electron atom enclosed within an infinitely hard spherical cavity of radius R and develop the method and calculations so that we may recover the free-atom case when . This procedure also allows to look at the evolution of its ground state energy as the cage volume shrinks as has been done elsewhere [25,53]. The TFDW energy-density functional for an atom enclosed within a spherical cavity of radius R is written as... [Pg.346]

However, the melt volume shrinks as crystallization proceeds. Hence, one can write... [Pg.365]

The H-bonds between H,0 and C H OH molecules are stronger than the H-bond between the like molecules of the individual compounds. The H,0 and C,H,OH molecules are closer when mixed, and the volume shrinks. [Pg.27]

Suppose that the atoms are distributed in space as in Fig. 1.5.6 Consider the behavior of the concentration of i—defined by (number of atoms of type i)/(volume)— as the volume shrinks toward the point where c(f) is evaluated as in Fig. 1.6. Apparently, the limiting value used intuitively to define the concentration c(f) is... [Pg.11]

The crystal volume shrinks on the right and VK expand on the left... [Pg.225]

As the liquid is cooled, its volume shrinks, presumably due to both a contraction of volume occupied by the molecules, and a contraction of the free volume Vf between... [Pg.197]

With MRI, there is often a volume mismatch between tissue showing reduced water molecule diffusion (a signature for cell swelling and ischemic tissue) and a larger area of compromised tissue perfusion early after stroke onset - the so-called diffusion/perfusion mismatch. The difference, at least for all practical purposes, is believed to reflect the ischemic penumbra [138, 148-151]. Perfusion MRI currently affords a relative, rather than absolute, quantitative measure of cerebral tissue perfusion. Many studies have shown that the MRI-documented mismatch volume shrinks over time. However, mismatch may persist, for example those who present beyond 3 h and still have substantial mismatch [152], suggesting a longer window of therapeutic opportunity in select patients. [Pg.11]

It follows from the above discussion that as the solvent is made poorer, i.e., as t /i (1 - 0/T) decreases, the excluded volume shrinks and at T = 0 it disappears entirely. In other words, as the solvent becomes poorer, polymer-polymer repulsion ditninishes and at the 0-point the net interaction becomes zero. Where T < 9, polymer molecules attract each other and the excluded volume is negative. When the temperature is much lower than the 0-point, precipitation occurs. [Pg.330]

The volume demand for some substances in certain solvents can even be negative. The volume shrinks when such a substance is dissolved. An example of this is the solution of sodium hydroxide in water ... [Pg.223]

The polymer always has a greater density than the monomer, i.e., the volume shrinks during polymerization. [Pg.36]

Look at the balloon in the middle of Figure 13-4. What do you think would happen to the balloon if you placed it in the freezer It d get smaller. Inside the freezer, the external pressure, or atmospheric pressure, is the same, but the gas particles inside the balloon aren t moving as fast, so the volume shrinks to keep the pressure constant. If you heat the balloon, the balloon expands and the volume increases. This is a direct relationship — as the temperature increases, the volume increases, and vice versa. [Pg.219]

There are regions close to the impeller where dispersion predominates. For scale-up under geometrically similar conditions, the effective dispersion volume shrinks with increasing vessel size. [Pg.696]

Hirotsu studied the phase transition of gels obtained from copolymerizing NIPAAm and acrylic acid in an electric field [63], The phase-transition temperature of this gel is approximately 39°C. However, this transition decreases to 31°C with an electric field of 10 V/cm. If the direct voltage is applied to this gel the volume shrinks while vibrating. Although the mechanism has yet to be understood, it is nonetheless a very interesting phenomenon. [Pg.699]

The volume does not change with the nitrate ion but with an iodide ion it swells. On the other hand, volume shrinks -with chlorine, sulfate, and phosphate ions [21]. The effect of anions on the swelling behavior of gels relates to the ratio (n/vi), the valence n of the anion, and radius of the ion... [Pg.1443]


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See also in sourсe #XX -- [ Pg.87 , Pg.96 ]




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Shrinking

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