Nitrogen distribution at 77.7 K in mesoporous Gelsil 50 generated via evolutionary minimization with statistical descriptors derived from adsorption and in situ SANS

Digitized periodic material models of size 1003 nm3 of mesoporous xerogel Gelsil 50 are reconstructed by use of an evolutionary minimization technique, with two point probability S r and volume based pore size distribution F D as a hybrid target function. S r and F D are derived from small angle neutron scattering SANS and adsorption data, respectively. The nitrogen distribution in Gelsil 50 is characterized in the multilayer adsorption and capillary condensaiton regimes by S r and statistical parameters obtained from in situ SANS data. The evolutionary algorithm is also used to generate the spatial nitrogen distribution by means of the descriptors liquid free pore space, S r and the size distribution of the liquid free pore spac

Numerical simulation of jet mixing noise associated with engine exhausts

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Reconstruction of the mesoporous silica glass Gelsil 50

A stochastic optimization technique is applied to the construction of three dimensional models of Debye random media and random ensembles of mono disperse penetrable sphere

Knowledge based reconstruction of random porous media

An evolutionary optimization technique is used to reconstruct digitized material models of 3003 ,nm3 size for mesoporous two phase systems. The models are adapted to the two point probability TPP and to a volume based pore size distribution PSD which were derived from SANS and adsorption experiments and which carry statistical information about morphology and topology of the pore system. To avoid extreme update costs, the bulk of mutations are assessed by means of a suitable approximation of the PSD; it is demonstrated that a sporadic insertion of the PSD suffices to drive the algorithm towards satisfactory models in acceptable time. Our approach is knowledge based in the sense that i the mutations are restricted to expedient exchanges of phase voxels by a heuristic rule, and ii the sporadic calculation of the PSD from the current state of the model, in essence, provides an efficient self control for the evolutionary process. We applied the method to reconstruct periodic models of the xerogel Gelsil 200. Such reconstructs of real mesoporous solids could be utilized, for instance, to verify theories of adsorption and capillary condensatio

Die spezifische Rolle kleiner und mittlerer Betriebe der metallverarbeitenden Industrie im Prozess der weiteren Vergesellschaftung der Produktion

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