INDEX particle stress

By plotting the percentage of carbon particles separated from the vulcanizate versus the stress applied to the sample during extension, Hess et al. determined the stress at which the arbitrary quantity of 20% of the black had been separated from the matrix. This stress was indicated as the adhesion index. It appears (Fig. 12) that blacks of higher structures are associated with an increase of the adhesion index, i.e., with an enhancement of filler-elastomer interactions. 

In a series of lectures, the improvements effected using the Coulter double lens system and PIDS are discussed [156]. Scattering intensity falls off rapidly as 6 increases the effect of this is reduced using PIDS which also enables the lower limit of measurement to be reduced to 0.05 pm. PIDS system has been applied to size determination of several pigments [157]. The importance of the imaginary part of the refractive index, in calculation of particle size distribution, was stressed. 

The third Hiestand Index is the stain index. It is a measure of the strain, associated with the release of elastic stresses after plastic deformation. It can be calculated by taking a ratio of Ho/E where Ho is the dynamic indentation hardness of the compact including particles and pores. 

For example, the cohesion of dairy powders has been studied with an unconfined yield test by preparing cylindrical plugs of powder at different particle sizes and moistures. Unconfined yield stress values were obtained as an index of cohesion for whole milk powder and skim milk powder. Dry... 

It is seen to contain two parameters m referred to as the consistency index with units of Pa s" and the dimensionless power law exponent . If = 1, the fluid is Newtonian and m = fi. For < 1, the fluid is shear thinning and the shear stress—shear rate slope decreases monotonically with increasing shear rate for > 1, the fluid is shear thickening and the stress-shear rate slope increases with increasing shear rate. We have already indicated that most macromolecular non-Newtonian fluids are shear thinning, however, shear thickening behavior is also observed over some ranges of shear rate with a number of polymer solutions and concentrated particle suspensions (Barnes et al. 1989). 

Narciso SP, Nadziejko E, Chen LC et al (2003) Adaptation to stress induced by restraining rats and mice in nose-only inhalation holders. Inhalation Toxicol 15 1133-1143 National Institute of Standards and Technology (NIST), http //ts.nist.gov/measurementservices/ referencematerials/index.cfm. Accessed 17 September 2009 Nemmar A, Hoet PHM, Vanquickenborne B et al (2002) Passage of inhaled particles into the blood circulation in humans. Circulation 105 411-414... 

Basically, birefringence is the contribution to the total birefringence of two-phase materials, due to deformation of the electric field associated with a propagating ray of light at anisotropically shaped phase boundaries. The effect may also occur with isotropic particles in an isotropic medium if they dispersed with a preferred orientation. The magnitude of the effect depends on the refractive index difference between the two phases and the shape of the dispersed particles. In thermoplastic systems the two phases may be crystalline and amorphous regions, plastic matrix and microvoids, or plastic and filler. See amorphous plastic coefficient of optical stress compact disc crystalline plastic directional property, anisotropic ... 

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