کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
8910883 1637933 2018 34 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
The effects of charge, polymerization, and cluster size on the diffusivity of dissolved Si species in pore water
ترجمه فارسی عنوان
اثرات شارژ، پلیمریزاسیون و اندازه خوشه بر انتشار مواد سمی محلول در آب معدنی
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات ژئوشیمی و پترولوژی
چکیده انگلیسی
Silicon (Si) is the most abundant cation in crustal rocks. The charge and degree of polymerization of dissolved Si significantly change depending on solution pH and Si concentration. We used molecular dynamics (MD) simulations to predict the self-diffusion coefficients of dissolved Si, DSi, for 15 monomeric and polymeric species at ambient temperature. The results showed that DSi decreased with increasing negative charge and increasing degree of polymerization. The relationship between DSi and charge (Z) can be expressed by DSi/10−6 = 2.0 + 9.8e0.47Z, and that between DSi and number of polymerization (NSi) by DSi/10−6 = 9.7/NSi0.56. The results also revealed that multiple Si molecules assembled into a cluster and D decreased as the cluster size increased. Experiments to evaluate the diffusivity of Si in pore water revealed that the diffusion coefficient decreased with increasing Si concentration, a result consistent with the MD simulations. Simulation results can now be used to quantitatively assess water-rock interactions and water-concrete reactions over a wide range of environmentally relevant conditions.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Geochimica et Cosmochimica Acta - Volume 224, 1 March 2018, Pages 301-312
نویسندگان
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