Segregation, strong/weak

The disordered arrangement of the globuh and worm-hke species in combination with their uniform shape and diameter of 50 A demonstrates that the intramolecular self-assembly did not depend on intermolecular ordering. For both types of particles, the monolayer thickness was similar to the lateral diameter of the particles d = 50 5A. The topographic contrast of the images in Fig. 6 was enabled by strong molecular segregation and weak interpenetration of the particles. 

Covers for the melt can be used. Prebumed charcoal has been successfully used as a cover and is appHed hot directly from the prebumer. Fluxing and deoxidation is not necessary because of the strong affinity silicon has for oxygen. Silicon-heating scrap must be kept segregated from other scrap, because silicon as an impurity ia other alloys can promote a very coarse dendritic stmcture and weak porous castings. 

Matson M.W. and Bates E.S., Unifying weak- and strong-segregation block copolymer theories. Macromolecules, 29, 1091, 1996. 

Recently, Grason and Kamien calculated the phase diagrams in the weak and strong segregation limit for AB miktoarm-star copolymers using both... 

This luminescence band is believed to be due to segregation of defects B1, which is a relatively large spheroid of aggregates of nitrogen and is characterized by strong N9 (236 and 230.8 nm) and weak NIO (240 and 248 nm) absorption systems. It gives white-blue luminescence (Fig. 4.71) excited by UV shorter that 240 nm with practically structureless broadband. Its luminescence decay is characterized by three components, mainly 25 ns, 100 ps and 3 ms. 

Fig. 2.1 Composition profiles of A and B components in the weak and strong segregation limits, compared to the mean (straight line).

Computer simulations of a range of properties of block copolymer micelles have been performed by Mattice and co-workers.These simulations have been based on bead models for copolymer chains on a cubic lattice. Types of allowed moves for bead chains are illustrated in Fig. 3.27. The formation of micelles by diblock copolymers under weak segregation conditions was simulated with pairwise interactions between A and B beads and between the A bead and vacant sites occupied by solvent, S (Wang et al. 19936). This leads to the formation of micelles with a B core. The cmc was found to depend strongly on fVB and % = x.w = %AS. In the range 3 < (xlz)N < 6, where z is the lattice constant, the cmc was found to be exponentially dependent onIt was found than in the micelles the insoluble block is slightly collapsed, and that the soluble block becomes stretched as Na increases, with [Pg.178]

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