Reconsideration of the dielectric properties response of concentration dependence of aqueous urea solution at the microwave frequency

Abstract

In this paper, we investigate the dielectric properties of aqueous urea solution over the frequency range 200 MHz–20 GHz. We reveal the single nature of urea–water cooperative interaction and draw a profile of the overview that urea–water cooperative interaction plays a dominating role in the aqueous urea solution system using Cole–Cole analysis. The self-diffusion coefficient is related to the concentration of the urea aqueous solution. The decay of the effective number of water molecules bound to the urea molecules with its concentration and the urea perturb the water structure beyond the first hydration shell, which is confirmed in the aqueous urea solution system. And the relation between $\tau$ and $\alpha$ may be utilised widely to measure the urea concentration for a microwave biosensor technique.

Keywords:

• Dielectric property response
• microwave frequency
• cooperative interaction

Acknowledgements

The authors sincerely acknowledge the anonymous reviewer of Physics and Chemistry of Liquids for precious advice to make their paper more substantial in content and improve its readability. Y.G. acknowledges Miss Qian Jie and Miss Li Xun for improving the language and revising the grammar.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China [grant number 61102044].