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Free energy and chemical potential in the Flory-Huggins model for N A N B 1. Points S are spinodal points; points B are binodal points of coexisting compositions.
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We critically review dissipative particle dynamics (DPD) as a mesoscopic simulation method. We have established useful parameter ranges for simulations, and have made a link between these parameters and χ-parameters in Flory-Huggins-type models. This is possible because the equation of state of the DPD fluid is essentially quadratic in density. Thi...
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... hence A B 1. Under this condition B 1 A , and A is the only degree of freedom. When A and B are two components that do not favor contact the parameter is positive; when they favor each other over AA or BB contacts, then it is negative. For suffi- ciently large -parameters the free energy develops two minima, separated by a maximum, see Fig. 5. If N A N B the minimum free energy is found at F/ A 0. In Fig. 5 these points are indicated by a B. Their location follows from the implicit ...
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... only degree of freedom. When A and B are two components that do not favor contact the parameter is positive; when they favor each other over AA or BB contacts, then it is negative. For suffi- ciently large -parameters the free energy develops two minima, separated by a maximum, see Fig. 5. If N A N B the minimum free energy is found at F/ A 0. In Fig. 5 these points are indicated by a B. Their location follows from the implicit ...
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... is positive but too small, no segregation will take place, but when it exceeds a critical value A-rich and B-rich do- mains will occur. This critical -parameter is found from the condition that the spinodals S in Fig. 5 coincide. This im- plies that the first and second derivative of the chemical po- tential with respect to A vanish, which leads to the critical point crit 1 2 ...
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