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71.
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Tomislav Fratrovi? Eduard Maruši?-Paloka 《Journal of Mathematical Analysis and Applications》2011,373(2):399-409
We study a stationary, purely viscous polymer flow through a porous medium modelled as a periodic array of cells consisted of a fluid part and a solid one. Solid parts of the domain present impermeable obstacles, whose impact on fluid flow may be seen as a slowing factor through averaged quantities such as the permeability function, obtained by the homogenization process. In that way, the influence of the microstructure is implemented in the homogenized equations through a kind of nonlinear Darcy's law. Our goal is to find more explicitly the dependence of the permeability function on the size η of the obstacle in the unit cell and the so-called low-volume-fraction limit. Main difficulties arise from the nonlinear character of the power-law viscosity and the apparent weak convergence of the solutions involved. 相似文献
73.
Štefica Cerjan Stefanović Tomislav Bolanča Melita Luša Šime Ukić Marko Rogošić 《Analytica chimica acta》2012
This paper describes the development of ad hoc methodology for determination of inorganic anions in oilfield water, since their composition often significantly differs from the average (concentration of components and/or matrix). Therefore, fast and reliable method development has to be performed in order to ensure the monitoring of desired properties under new conditions. The method development was based on computer assisted multi-criteria decision making strategy. The used criteria were: maximal value of objective functions used, maximal robustness of the separation method, minimal analysis time, and maximal retention distance between two nearest components. Artificial neural networks were used for modeling of anion retention. The reliability of developed method was extensively tested by the validation of performance characteristics. Based on validation results, the developed method shows satisfactory performance characteristics, proving the successful application of computer assisted methodology in the described case study. 相似文献
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We show that during cosmological inflation the nonsymmetric metric tensor theory of gravitation develops a spectrum which is potentially observable by cosmic microwave background observations, and may be the most sensitive probe of the scale of cosmic inflation. 相似文献
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Sandra Kaabel Robin S. Stein Maria Fomitenko Ivar Jrving Tomislav Fri
i Riina Aav 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(19):6296-6300
Self‐organization is one of the most intriguing phenomena of chemical matter. While the self‐assembly of macrocycles and cages in dilute solutions has been extensively studied, it remains poorly understood in solvent‐free environments. Provided here is the first example of using anionic templates to achieve selective assembly of differently‐sized macrocycles in a solvent‐free system. Using acid‐catalyzed synthesis of cyclohexanohemicucurbiturils as a model, size‐controlled, quantitative synthesis of 6‐ or 8‐membered macrocycles by spontaneous anion‐directed reorganization of mechanochemically‐made oligomers in the solid state is demonstrated. 相似文献
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JPC – Journal of Planar Chromatography – Modern TLC - This paper explores the high-performance thin-layer chromatographic (HPTLC) fingerprinting of non-sugar constituents for the... 相似文献