Mass fraction of crystals

This quantity, which is often referred to as magma density or soHds concentration (mass of crystals per unit system volume), is often an important process variable. A cumulative mass fraction of crystals having a size less than U can also be defined as... 

A slurry contains crystals of copper sulfate pentahydrate [CuS04-5H20(s), specific gravity = 2,3] suspended in an aqueous copper sulfate solution (liquid SG = 1.2). A sensitive transducer is used to measure the pressure difference, A/ (Pa), between two points in the sample container separated by a vertical distance of h meters. The reading is in turn used to determine the mass fraction of crystals in the slurry, Xc(kg crystals/kg slurry). 

Besides, without addictive AICI3 as a crystal conversion agent, phase composition of most neogenic Ti02 particles was anatase in our experiment. Conversions active energy finm anatase to rutile was 460 kJ/mol [5], with temperature arose, crystal conversion rate as well as mass fraction of rutile would increase [6,7]. Hence, after a lot of heat accumulated, phase composition of particle-sintered layer was rutile. 

Figure 17. Plot of Li isotopic composition vs. temperature of growth for synthetic calcite crystallized from a solution containing Li from L-SVEC (Marriott et al. 2004). The results are most consistent with temperature not being a significant control on mass fractionation of Li during crystallization from aqueous solution, thus essentially eliminating Li isotopes as a paleotemperature proxy in marine carbonates.

Ammonium perchlorate (AP NH4CIO4) is a white, crystalline material, the crystal structure of which changes from orthorhombic to cubic at 513 K, which affects the decomposition process. AP is not hygroscopic in the atmosphere and the mass fraction of oxygen is 0.545. It is used as an oxidizer in various types of propellants and pyrolants. A rapid sublimation occurs between 670 K and 710 K at low pressures. Under slow heating, AP starts to decompose at about 470 K according to ... 

Ammonium nitrate (AN NH4NO3) is a white, crystalline material, the crystal structure of which varies with temperature.melting point is 442 K and its heat of fusion is 71.4 kj kg . Though the mass fraction of oxygen of AN is 0.5996, it is highly hygroscopic and absorbs moisture from the atmosphere to form liquid AN acid. This limits its application in propellants and pyrolants. However, AN is widely used as an oxidizer of explosives such as slurry explosives and ANFO (ammonium nitrate fuel oil) explosives. 

Crystal growth Consider the case for crystal growth along one direction (hence a one-dimensional problem). Define the initial interface to be at x = 0 and the crystal is on the side with negative x (left-hand side) and the melt is on the positive side (Section 3.4.6). Due to crystal growth, the interface advances to the positive side. Define the interface position at time t to be at x = Xq, where Xq > 0 is a function of time. Let w be the mass fraction of the main equilibriumdetermining component then the diffusion equation in the melt is... 

Molecular Weight Dependence of Phase Structure. Similar line shape analysis was performed for samples with molecular weight over a very wide range that had been crystallized from the melt. In some samples, an additional crystalline line appears at 34.4 ppm which can be assigned to trans-trans methylene sequences in a monoclinic crystal form. Therefore the spectrum was analyzed in terms of four Lorentzian functions with different peak positions and line widths i.e. for two crystalline and two noncrystalline lines. Reasonable curve fitting was also obtained in these cases. The results are plotted by solid circles on the data of the broad-line H NMR in Fig. 3. The mass fractions of the crystalline, amorphous phases and the crystalline-amorphous interphase are in good accord with those of the broad, narrow, and intermediate components from the broad-line NMR analysis. 

Fig. 13. Mass fractions of three phases of bulk polyethylene versus weight-average molecular weight, obtained by broad-line JH NMR analyses. Solid lines indicate high-pressure crystallized samples, while broken lines show samples which were isothermally crystallized under atmospheric pressure...

Figure 1. Kinetics of crystallization of zeolite X (Figure A) and zeolite Na-Pc (Figure B) at 80°C, from the aluminosilicate gels aged for tQ = 1 d ( ), tQ = 3 d (A), ta = 5 d (A), ta = 7 d ( ) and ta = 10 d (o) at 25°C. f and fpc are mass fractions of zeolite X and zeolite Na-Pc crystallized at crystallization time tc. Solid curves represent the kinetics of crystallization, calculated by Equation (1) and the corresponding values of the constants K and q from Table I.

Figure 2. The changes in A. mass fractions of zeolite X (o), fpc of zeolite Na-Pc ( ) and fg of gel (A), B. concentrations C [(L) of aluminum ( ) and Cgj(L) of silicon (o) in the liquid phase and C. molar ratio [ Si/Al]s in the solid phase (o), with the crystallization time tc, during the crystallization from the gel aged for ta = 1 d.

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