Coarse-Grained Components

Understanding the fundamental issues from the atomic or molecular scale to macroscopic morphology in such a complex system is challenging. Most analytical theories [11] are severely limited for such complex systems that exhibit linear and nonlinear response properties on different spatial and temporal scales. Computer simulations remain the primary choice to probe multiscale phenomena from microscopic characteristics of constituents to macroscopic observables in such complex systems. Most real systems [9] are still too complex to be fully addressed by computing and computer simulations alone. Coarse-grained descriptions are almost unavoidable in developing models for such nanocomposite systems. 

---

Because these pipes are key components used for airplanes, their ultrasonic testing quality must be guranteed. Therefore, the author has conducted studies about the flaw detection methods for coarse-grained TC4P extrusion pipes. 

The next most important mechanism affecting the surface tension at a single component simple fluid gas-liquid interface is, we believe, associated with the nonlocality of the repulsive interaetions. To account for this mechanism, observe that it enters by way of the exeluded volume effeet. In the coarse-grained GvdW(S) theory above, the free volume faetor /(r) is given by... 

At the antipodes of the latter description, there is a continuous need for better low-resolution models that involve, for instance, coarse graining of molecules, or implicit solvation. This need is motivated by the expectation that the free energy of a large system can be calculated with sufficient accuracy without requiring that all its components be described at the atomic level. In many cases, this is equivalent to the assumption that a mean-field approximation works, or that many fast degrees of freedom can be removed from the system, yet without any appreciable loss of... 

At the mesoscopic scale, interactions between molecular components in membranes and catalyst layers control the self-organization into nanophase-segregated media, structural correlations, and adhesion properties of phase domains. Such complex processes can be studied by various theoretical tools and simulation techniques (e.g., by coarse-grained molecular dynamics simulations). Complex morphologies of the emerging media can be related to effective physicochemical properties that characterize transport and reaction at the macroscopic scale, using concepts from the theory of random heterogeneous media and percolation theory. 

Coarse-grained molecular d5mamics simulations in the presence of solvent provide insights into the effect of dispersion medium on microstructural properties of the catalyst layer. To explore the interaction of Nation and solvent in the catalyst ink mixture, simulations were performed in the presence of carbon/Pt particles, water, implicit polar solvent (with different dielectric constant e), and ionomer. Malek et al. developed the computational approach based on CGMD simulations in two steps. In the first step, groups of atoms of the distinct components were replaced by spherical beads with predefined subnanoscopic length scale. In the second step, parameters of renormalized interaction energies between the distinct beads were specified. 

The most primitive chondrites consist of coarse-grained (mm-sized) mineral assemblages embedded in fine-grained (10 nm-5 pm) matrix material (see Fig. 1.2). The coarse-grained chondritic components are diverse in their composition and mineralogy and include calcium-aluminum-rich inclusions (CAIs), amoeboid olivine aggregates (AOAs), Al-rich chondrules, Fe-Mg chondrules, Fe-rich metals, and iron sulfides. The CAIs are composed largely of calcium, aluminum, and titanium... 

I and rich in component II. The inhomogeneous site-site direct correlation function is represented by an average of two homogeneous terms parametrically dependent on the coarse-grained density profiles p(Fi) and p(F2) at the two given positions. 

In order to include the stractural component of proton diffusion, a coarse-grained RMD algorithm has been developed to study stractural diffusion. The algorithm is composed of three steps ... 

The ureilites are the most remarkable of the primitive achondrites. They are coarse-grained, carbon-bearing ultramafic rocks, and are residues of extensive partial melting that has removed a basaltic component. Their oxygen isotopic compositions are highly variable, and extend along an extrapolation of the CCAM line. The isotopic variability is probably inherited from heterogeneous carbonaceous chondrite precursors (Clayton and Mayeda, 1988). 

This can be illustrated by a natural example. In the coarse-grained Allanin magnesium-gabbro, infiltration of fluid caused the formation of reaction rims around olivine (Chinner and Dixon, 1973). The succession is olivine anthophyllite (2 wt.% H2O) — talc (4wt.% H2O + kyanite — chloritoid (8wt.% H20- -talc + kyanite. This reaction rim is H2O undersaturated, and the succession of mineral assemblages corresponds to an increase of H2O content towards the rim and can only be modeled by an increase in the availability of water towards the rim. The H20-undersamrated character of the inner rim zones does not necessitate (or justify) a CO2 component in the fluid, but rather reflects limited availability of an H2O fluid. 

---