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Nucleation crystallization

The resistance to nucleation is associated with the surface energy of forming small clusters. Once beyond a critical size, the growth proceeds with the considerable driving force due to the supersaturation or subcooling. It is the definition of this critical nucleus size that has consumed much theoretical and experimental research. We present a brief description of the classic nucleation theory along with some examples of crystal nucleation and growth studies. [Pg.328]

As r -> 0, AT -> 00, showing that the lateral dimensions of the plate are critical for very small crystals. This makes the crystal nucleation event especially crucial. [Pg.215]

Scaling is not always related to temperature. Calcium carbonate and calcium sulfate scaling occur on unheated surfaces when their solubiUties are exceeded in the bulk water. Metallic surfaces are ideal sites for crystal nucleation because of their rough surfaces and the low velocities adjacent to the surface. Corrosion cells on the metal surface produce areas of high pH, which promote the precipitation of many cooling water salts. Once formed, scale deposits initiate additional nucleation, and crystal growth proceeds at an accelerated rate. [Pg.270]

Barium bromide is very soluble in methanol, yet almost insoluble in ethanol. Repotted uses of barium bromide include fabrication of phosphors, for example from Bap2, BaBi2 2H O and EuBy (6) as a crystallization nucleating agent to control supercooling of CaBi2 solutions (7) and in the production... [Pg.476]

Tempering. The state, or physical stmcture, of the fat base in which sugar, cocoa, and milk soHds are suspended is critical to the overall quaHty and stabiHty of chocolate. Production of a stable fat base is compHcated because the cocoa butter in soHdified chocolate exists in several polymorphic forms. Tempering is the process of inducing satisfactory crystal nucleation of the Hquid fat in chocolate. [Pg.95]

Along with operating variables of the crystallizer, nucleation and growth determine such crystal characteristics as size distribution, purity, and shape or habit. [Pg.342]

Nucleation. Crystal nucleation is the formation of an ordered soHd phase from a Hquid or amorphous phase. Nucleation sets the character of the crystallization process, and it is, therefore, the most critical component ia relating crystallizer design and operation to crystal size distributions. [Pg.342]

A. D. Randolph and D. Etherton, Study of Gypsum Crystal Nucleation and Growth Rates in Simulated Flue Gas Desulfurization Eiquors, EPRI Report CS1885, Electric Power Research Institute, Palo Alto, Calif., 1981. [Pg.28]

Nucleation The mechanism of crystal nucleation from solution has been studied by many scientists, and recent work suggests that—in commercial crystallization equipment, at least—the nucleation rate is the sum of contributions by (1) homogeneous nucleation and (2) nucleation due to contaci between crystals and a) other crystals, h) the walls of the container, and (c) the pump impeller. If is the net number of new crystals formed in a unit volume of solution per unit of time. [Pg.1658]

Tavare, N.S. and Garside, J., 1986. Simultaneous estimation of crystal nucleation and growth kinetics from batch experiments. Chemical Engineering Research and Design, 64, 109. [Pg.324]

Second, the molecular orientation of the fiber and the prepolymer matrix is important. The rate of crystal nucleation at the fiber-matrix interface depends on the orientation of matrix molecules just prior to their change of phase from liquid to solid. Thus, surface-nucleated morphologies are likely to dominate the matrix stmcture. [Pg.85]

Transfomation from a meta-stable phase, such as supersaturated solution, to a thermodynamically more favorable phase requires first the crystal nucleation of a germ of the new phase. According to the classical nucleation theory, the volume nucleation rate J (cm" sec ), describing the number of nuclei(i.e., a critical germ) formed per volume per time, is given by ... [Pg.682]

As can be seen from Fig. 6, liquid-liquid demixing clearly precedes crystallization in case Cl. Moreover, crystallization in this case occurs at a higher temperature than in cases C2 and C3. Apparently, the crystallization takes place in the dense disordered phase (which has a higher melting temperature than the more dilute solution Fig. 5). In case C2, the crystallization temperature is close to the expected critical point of liquid-liquid demixing, but higher than in case C3. This suggests that even pre-critical density fluctuations enhance the rate of crystal nucleation. [Pg.14]

Equation 20 predicts a free-energy barrier for primary crystal nucleation (i.e., the free-energy difference between the top of the barrier and the initial coil state) as... [Pg.25]

Kelton KF (1991) In Ehrenreich H, Turnbull D (eds) Crystal nucleation in liquids and glasses. Academic, Boston, p 75... [Pg.34]

Keywords Induction period Melt and glass crystallization Nucleation and growth Optical microscopy Scattering techniques Spinodal decomposition... [Pg.185]


See other pages where Nucleation crystallization is mentioned: [Pg.2286]    [Pg.2288]    [Pg.220]    [Pg.223]    [Pg.263]    [Pg.190]    [Pg.290]    [Pg.225]    [Pg.341]    [Pg.216]    [Pg.1620]    [Pg.1657]    [Pg.1670]    [Pg.68]    [Pg.92]    [Pg.144]    [Pg.256]    [Pg.164]    [Pg.124]    [Pg.1045]    [Pg.126]    [Pg.805]    [Pg.116]    [Pg.141]    [Pg.144]    [Pg.247]    [Pg.260]    [Pg.13]    [Pg.14]    [Pg.185]    [Pg.187]    [Pg.188]   
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A-crystal nucleating agent

Accelerated Crystal Nucleation at Liquid Interfaces

Accelerated Crystal Nucleation in the Concentrated Phase

Atomistic Simulations of Crystal Nucleation and Growth

Chain entropy, polymer crystal nucleation

Chain growth, polymer crystal nucleation

Crystal Nucleation Rate

Crystal contact nucleation

Crystal formation nucleation

Crystal growth and nucleation kinetics

Crystal growth nucleation

Crystal growth surface nucleation mechanism

Crystal nucleating agent

Crystal nucleation

Crystal nucleation

Crystal nucleation kinetics

Crystal nucleation temperature

Crystal nucleation theory

Crystal nucleation, computer simulation

Crystal nucleation, pure melt

Crystal structure nucleating agents

Crystal surface nucleation

Crystal, defect, point nucleation,

Crystallization by nucleation and growth

Crystallization dimensionless nucleation

Crystallization heterogeneous nucleation

Crystallization homogeneous nucleation

Crystallization kinetics, polymer crystal nucleation

Crystallization nucleated

Crystallization nucleated

Crystallization nucleating agents

Crystallization nucleation and growth

Crystallization nucleation rate

Crystallization nucleation theories

Crystallization secondary nucleation

Crystallization solution-precipitation nucleation

Crystallization, fats nucleation

Crystallizer dimensionless nucleation

Crystallizers contact nucleation

Crystallizers nucleation

Crystallizers nucleation

Density fluctuations, polymer crystal nucleation

Dislocation nucleation in a perfect crystal

Equilibrium melting temperature, polymer crystal nucleation

Flow effects, polymer crystal nucleation

Fold surfaces, lamellae, polymer crystal nucleation

Food crystallization nucleation

Heterogeneous nucleation affecting crystallization rate

Homogeneous Nucleation and Fractionated Crystallization

Homogeneous Nucleation and Fractionated Crystallization in Block Copolymer Microdomains

Homogeneous nucleation rate, polymer crystal

Homopolymers, crystallization kinetic homogeneous nucleation

Homopolymers, crystallization kinetic nucleation rate

Homopolymers, crystallization kinetic nucleation theory

Initiation of Crystallization - Nucleation Phase

Intramolecular crystal nucleation

Intramolecular crystal nucleation model

Isothermal crystallization nucleation rate

Kinetics of Crystal Nucleation

Lamellae properties, polymer crystal nucleation

Lauritzen-Hoffman theory, polymer crystallization secondary nucleation

Melting temperature, polymer crystal nucleation

Molecular Aspects on the Dissolution and Nucleation of Ionic Crystals

Molecular Aspects on the Dissolution and Nucleation of Ionic Crystals in Water

Molecular modeling, polymer crystal nucleation

Molecular nucleation, polymer crystal

Monte Carlo simulation polymer crystal nucleation

Morphology and Crystal Nucleation

Nonisothermal crystallization nucleation rate

Nucleated crystal, ratio

Nucleation Crystallization Specific

Nucleation Processes of Alkali Halide Crystals

Nucleation and Crystal Growth Lauritzen-Hofmann Theory

Nucleation and Crystal Growth in MSMPR Crystallizers

Nucleation and crystal growth

Nucleation and growth of many crystals

Nucleation and the Crystal Growth Process

Nucleation competition with crystal growth

Nucleation control, crystal growth

Nucleation control, crystal growth solution

Nucleation crystal growth rates

Nucleation crystal-growing techniques

Nucleation in crystal growth

Nucleation in crystallization

Nucleation of Cholesterol Crystals

Nucleation of Polymer Crystallization

Nucleation of crystallization

Nucleation of crystals

Nucleation of crystals from solution

Nucleation polymer crystal growth

Nucleation protein crystal

Nucleation protein crystallization

Nucleation, crystal fundamentals

Nucleation, crystal heterogeneous

Nucleation, crystal homogeneous

Nucleation, crystal molecular

Nucleation, crystal tertiary

Nucleation, crystallization behaviors

Nucleation, polymer crystallization

Nucleation, polymer crystallization elongational flow

Nucleation, polymer crystallization flow effects

Nucleation, polymer crystallization initial crystals

Nucleation, polymer crystallization lamellae characteristics

Nucleation, polymer crystallization molecular modeling

Nucleation, polymer crystallization origins

Nucleation, polymer crystallization phenomenology

Nucleation, polymer crystallization regime

Nucleation, polymer crystallization simulations

Nucleation, polymer crystallization spherical nucleus

Nucleation, polymer crystallization temperature dependence, lamellar

Nucleation, polymer crystallization theoretical model

Nucleation, polymer crystallization thermodynamics

Nucleation, polymer crystallization thickness

Nucleation-driven crystallization

Nucleation/crystal growth constant

Nucleation/crystallization promoter

PLA Crystallization Behavior and Nucleating Agents

Polymer crystallization heterogeneous nucleation

Polymer crystallization primary nucleation

Polymer crystallization sporadic nucleation

Polymer crystallization tertiary nucleation

Polymer crystals nucleation

Polymer surfaces, crystal nucleation affected

Primary crystal nucleation

Protein crystallization nucleation mechanism

Protein crystallization nucleation rate

Rate of Nucleation and Crystal Growth

Results for Nucleation-Driven Crystallization

Rubber crystallization, nucleating agent

Secondary crystal nucleation

Secondary nucleation, polymer crystallization

Secondary nucleation, polymer crystallization regime

Single chain models, polymer crystal nucleation

Spherical nucleus, polymer crystal nucleation

Spherulites lamellae, polymer crystal nucleation

Supercooling mechanisms, polymer crystal nucleation

Surface nucleation control, crystal

Temperature dependence, polymer crystal nucleation

The influence of mixing on nucleation and crystal growth

Theory of Crystal Nucleation and Growth

Thermodynamics, polymer crystal nucleation

Time-dependent measurements polymer crystal nucleation, crystallization

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