Illumination of Conjugated Polymers Reduces the Nucleation Probability and Slows Down the Crystal Growth Rate

Crystal growth rates of copper sulphate pentahydrate (CuSO4.5 H2O) determined by different authors and methods are compared. The methods included in this comparison are: (i) Measurement on a fixed crystal suspended in a streaming solution, (ii) measurement on a rotating disc, (iii) measurement in a fluidized bed, (iv) measurement in an agitated suspension. The comparison involves critical estimation of the supersaturation used in measurements, of shape factors used for data treatment and a correction for the effect of temperature. Conclusions are drawn for the choice of values to be specified when data of crystal growth rate measurements are published.

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Optical resolution of N-formylphenylalanine succeeds by crystal growth rate differences of diastereomeric salts

Tetrahedron Asymmetry ◽

10.1016/j.tetasy.2007.01.029 ◽

2007 ◽

Vol 18 (2) ◽

pp. 260-264 ◽

Cited By ~ 10

Author(s):

Laura Bereczki ◽

Emese Pálovics ◽

Petra Bombicz ◽

György Pokol ◽

Elemér Fogassy ◽

...

Keyword(s):

Growth Rate ◽

Crystal Growth ◽

Optical Resolution ◽

Crystal Growth Rate ◽

Diastereomeric Salts

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Crystal-growth kinetics of protein single crystals along capillary tubes in the gel-acupuncture technique

Acta Crystallographica Section D Biological Crystallography ◽

10.1107/s0907444998013985 ◽

1999 ◽

Vol 55 (2) ◽

pp. 577-580 ◽

Cited By ~ 3

Author(s):

Abel Moreno ◽

Manuel Soriano-García

Keyword(s):

Growth Rate ◽

Crystal Growth ◽

Capillary Tube ◽

Crystal Growth Rate ◽

Equilibrium Studies ◽

Acta Cryst ◽

Average Growth ◽

X Ray Crystallography ◽

Growing Cell ◽

Kinetics Of

In attempts to obtain protein crystals of a sufficient size for structural studies, lack of knowledge of the physicochemical properties of protein solutions and of their crystal-growth behaviour lead to a bottleneck for drug design as well as for X-ray crystallography. Most formal investigations on crystal-growth phenomena have been focused on equilibrium studies, where the protein is soluble, and on the kinetics of crystal growth, which is related to both nucleation and crystal-growth phenomena. The aim of this work is to measure the crystal-growth rate along a capillary tube used as a growing cell. These experiments were carried out using the gel-acupuncture technique [García-Ruiz et al. (1993). Mater. Res. Bull. 28, 541–546; García-Ruiz & Moreno (1994). Acta Cryst. D50, 484–490; García-Ruiz & Moreno (1997). J. Cryst. Growth, 178, 393–401]. Crystal-growth investigations took place using lysozyme and thaumatin I as standard proteins. The maximum average growth rate obtained in the lower part of the capillary tube was about 35 Å s−1 and the minimum average growing rate in the upper part of the capillary tube was about 8 Å s−1. The crystal-growth rate as a function of the supersaturation was experimentally estimated at a constant height along the capillary tube.

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Phase separation in undercooled molten Pd80Si20: Part I

Journal of Materials Research ◽

10.1557/jmr.1999.0493 ◽

1999 ◽

Vol 14 (9) ◽

pp. 3653-3662 ◽

Cited By ~ 31

Author(s):

K. L. Lee ◽

H. W. Kui

Keyword(s):

Growth Rate ◽

Phase Separation ◽

Crystal Growth ◽

Grain Refinement ◽

Crystallization Temperature ◽

Sharp Decrease ◽

Nucleation And Growth ◽

Crystal Growth Rate ◽

Large Undercooling ◽

Kinetic Crystallization

Three different kinds of morphology are found in undercooled Pd80Si20, and they dominate at different undercooling regimens ΔT, defined as ΔT = T1 – Tk, where T1 is the liquidus of Pd80Si20 and Tk is the kinetic crystallization temperature. In the small undercooling regimen, i.e., for ΔT ≤ 190 K, the microstructures are typically dendritic precipitation with a eutecticlike background. In the intermediate undercooling regimen, i.e., for 190 ≤ ΔT ≤ 220 K, spherical morphologies, which arise from nucleation and growth, are identified. In addition, Pd particles are found throughout an entire undercooled specimen. In the large undercooling regimen, i.e., for ΔT ≥ 220 K, a connected structure composed of two subnetworks is found. A sharp decrease in the dimension of the microstructures occurs from the intermediate to the large undercooling regimen. Although the crystalline phases in the intermediate and the large undercooling regimens are the same, the crystal growth rate is too slow to bring about the occurrence of grain refinement. Combining the morphologies observed in the three undercooling regimens and their crystallization behaviors, we conclude that phase separation takes place in undercooled molten Pd80Si20.

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