کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
608240 1454606 2012 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Dielectric spectroscopy of bidisperse colloidal suspensions
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی شیمی کلوئیدی و سطحی
پیش نمایش صفحه اول مقاله
Dielectric spectroscopy of bidisperse colloidal suspensions
چکیده انگلیسی

Dielectric spectroscopy is used to measure the complex permittivity of bidisperse colloidal suspensions over the frequency range 2.5 kHz ⩽ ω/2π ⩽ 10 MHz using the spectrometer design of Hollingsworth and Saville (A.D. Hollingsworth, D.A. Saville, J. Colloid Interface Sci., 2003). Dielectric spectra of monodisperse polystyrene spheres of two diameters (530 nm and 1 μm) are fit to electrokinetic theory using the surface charge density as an adjustable parameter. Quantitative agreement is found in the dielectric increment and also for the conductivity increment, after considering the effect of added counterions and nonspecific adsorption. Bidisperse suspension spectra are a linear superposition of each particle’s dielectric response. The results provide a simple method to extend standard electrokinetic theory based on a single particle size to dilute suspensions with many particle sizes and verify the sensitivity of the spectrometer.

Figure optionsDownload high-quality image (113 K)Download as PowerPoint slideHighlights
► Dielectric spectroscopy measurements of bidisperse polystyrene suspensions.
► Monodisperse suspension spectra agree with standard electrokinetic theory.
► Bidisperse spectra is a linear superposition of monodisperse suspension spectra.
► Validates and extends electrokinetic model calculations to polydisperse suspensions.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Colloid and Interface Science - Volume 380, Issue 1, 15 August 2012, Pages 34–41
نویسندگان
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