Grains Method

Experimental values cited in the program. Estimated values bWater solubility in ppm at 25 C. Estimated from log Kow Vapor pressure in mmHg estimated by the modified Grain method dSoil adsorption coefficient in L/kg estimated by log Kow... 

VP estimation is performed by the MPBPWIN program using three separate methods (1) the Antoine method, (2) the modified Grain method, and (3) the Mackay method. All three use the normal boiling point to estimate VP. Unless the user enters a boiling point on the data-entry screen, MPBPWIN uses the estimated boiling point from the adapted Stein and Brown method. When a boiling point is entered on the data entry screen, MPBPWIN uses it. Each VP method is discussed below. 

Modified Grain Method — See Dearden (2003) for a basic description of the modified Grain method used by MPBPWIN. This method is a modification and significant improvement of the modified Watson method (which is currently used by PC-PCHEM to estimate VP for solids). It is applicable to solids, liquids, and gases. It is probably the best all-round VP estimation method currently available. 

Dissipative Particle Dynamics (DPD) is a coarse graining method that groups several atoms into simulation sites whose dynamics is governed by conservative and frictional forces designed to reproduce thermodynamics and hydrodynamics [132,133]. Since the effective interactions are constmcted to reproduce macroscopic properties soft repulsive forces can be used, thereby avoiding the small MD step sizes needed to integrate the system when full interactions are taken into account. In addition, random... 

Particle-based methods have been linked to continuum models in order to exploit the efficiency of hnite element schemes and yet account for boundary layers and other regions where continuum approaches may fail [135]. It is very likely that coarse grained methods will continue to be developed and used since many physical systems are too large or too complex to be treated by full MD. 

Saunders, M. G., and G. A. Voth, Coarse-graining methods for computational biology, in Annual Review of Biophysics, vol 42, K. A. Dill, ed. 2013, Annual Reviews Palo Alto. pp. 73-93. 

Saunders, M.G., Voth, G.A. Coarse-graining methods for computational biology. Annu. Rev. Biophys. 42, 73-93 (2013)... 

Fig. 1.11 (a) A typical coarse-graining method replaces groups of atoms by ellipsoidal rigid bodies, (b) The Gay-Beme potential models the anisotropic interaction between nonspherical coarse-grained molecules potentials are described by the orientation of the molecules with respect to a fixed frame and the separation between their centers of mass... 

Andreev, V. Molchanov, O. (1987). Snow mold ofwinter grains (Methods of study and control measures). Moscow. Research Institute of Technic-Economic Researches, 46 p. 

Keywords Molecular Simulation Quanmm Atomistic Coarse-Grained Methods... 

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