Amorphous relative density

Melting point, °C 1000-1500 Relative density (water -1) 2.5 Solubility in water none WHITE, BROWN OR BLUE SOLID WITH FIBROUS CRYSTALLINE STRUCTURE Unable to react with virtually any other substance. Becomes powdery (amorphous) and loses Its hazardous properties when heated above approx. 1200°C. Processes entailing the release of fine fibers Into the air should be avoided wherever possible. ... 

Relative density (water 1) >2 Solubility in water none Relative molecular mass 431.7 Gross formula C04Zr WHfTE AMORPHOUS POWDER Dissolves in acids, releasing carbon dioxide gas. ... 

Figure 8.21 Finite element simulation of viscous sintering of two rigid particles coated with an amorphous layer (a) Rigid particles of radius a coated with a viscous layer of thickness s and showing the finite element mesh (b) predictions for the relative density versus reduced time for different coating thicknesses, and for the Mackenzie and Shuttleworth (M-S) model. (From Ref. 33.)...

Figure 11.63 Predicted effect of crystallization on the sintering of an amorphous gel. The density of the matrix p, volume fraction of crystals v, and the porosity P are plotted versus reduced time for a gel with initial relative density of 0.2. Calculations are shown for two values of the parameter C (a) C = 0.3 and (b) C = 3.0. (From Ref. 100.)...

The extrusion of the AlgsNisYio amorphous powder into an amorphous bulk at extrusion ratios of four and seven was tried by changing the extrusion temperature. The extruded bulk was obtained at temperatures above 543 K and the relative density was measured to be 0.969 at 543 K, 0.980 at 573 K, 0.987 at 603 K and 0.996 at 673 K. The... 

Closed-cell PEN foams were for the first time produced by Sorrentino, Aurilia, and lannace in 2011 (2011). They used a batch foaming apparatus to solubilize carbon dioxide into amorphous PEN. Foams were produced within an extended temperature range (from 100 to 240 C) and were characterized by relative densities ranging from 0.13 to 0.44 and average cell size between 5 and 15 pm. Cell nucleation strongly increased above PEN glass transition temperature, as a consequence of the higher molecular mobility. 

Reactants. The size classified powders of Mo (1-6 pm particle size), Ta (1-4 pm), B (amorphous, < 0.1-2.0 pm) and carbon black were used in the experiments. The admixed oxygen contents were 5, 6, 1, and = 1 at.%, respectively. The relative densities of the pressed samples were 0.6-0.7. 

The refractive index of amorphous silicon is. within certain limits, a good measure for the density of the material. If we may consider the material to consist of a tightly bonded structure containing voids, the density of the material follows from the void fraction. This fraction / can be computed from the relative dielectric constant e. Assuming that the voids have a spherical shape, / is given by Bruggeman [61] ... 

Recent investigations have indicated that the aliphatic carbon fraction, rather than aromatic fraction, was strongly correlated to HOC sorption. For instance, the sorption of phenanthrene was related to nonpolar aliphatic carbon fraction, excluding poly(methylene), but was very strongly correlated with the content of the amorphous nonpolar aliphatic domains including amorphous poly(methylene) (Mao et al. 2002). In other words, the rubbeiy, relatively low-density, and amorphous nonpolar aliphatic carbon domains are excellent for phenanthrene partitioning (Figs. 3 and 4). 

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