A comparison between experimental measurements and theoretical calculations of the permittivity and conductivity of concentrated colloidal suspensions is presented. Dielectric spectroscopy measurements for 100nm and 200nm diameter polystyrene spheres at volume fractions between ϕ=0.01-0.18 and electrolyte concentrations 0.01-1mM KCl (P.J. Beltramo, E.M. Furst, Langmuir 28 (2012) 10703-10712) are compared to cell-model calculations that account for the hydrodynamic and electrokinetic interactions between particles (F. Carrique, F.J. Arroyo, M.L. Jimenez, A.V. Delgado, J. Chem. Phys. 118 (2003) 1945-1956). Under most conditions, there is good agreement between experiment and theory. At low ionic strengths, the dielectric increment exhibits a low-frequency plateau in the experimental spectroscopy and cell model calculations. However, at the highest ionic strengths, the cell model predicts a low frequency plateau that is not observed experimentally. The conductivity increments qualitatively agree over all volume fractions, ionic strengths and frequencies.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.jcis.2013.07.042 | DOI Listing |
J Phys Chem B
January 2025
Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States.
In many simple viruses and virus-like particles, the protein capsid self-assembles around a nucleic-acid genome. Although the assembly process has been studied in detail, relatively little is known about how the capsid disassembles, a potentially important step for infection (in viruses) or cargo delivery (in virus-like particles). We investigate capsid disassembly using a coarse-grained molecular dynamics model of a = 1 dodecahedral capsid and an RNA-like polymer.
View Article and Find Full Text PDFMar Biotechnol (NY)
January 2025
East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai, 200090, China.
As an abiotic stress factor, salinity significantly affects the physiological activities of crustaceans. In this study, transcriptome sequencing was used to evaluate the mechanism of ion transport and the physiological response of black tiger shrimp (Penaeus monodon) under low salt stress. Four hundred post larval (PL) stage P.
View Article and Find Full Text PDFProc Biol Sci
January 2025
Department of Biology, California State University Northridge, Northridge, CA, USA.
Coral reefs experience numerous environmental gradients affecting organismal physiology and species biodiversity, which ultimately impact community metabolism. This study shows that submarine groundwater discharge (SGD), a common natural environmental gradient in coastal ecosystems associated with decreasing temperatures, salinity and pH with increasing nutrients, has both direct and indirect effects on coral reef community metabolism by altering individual growth rates and community composition. Our data revealed that SGD exposure hindered the growth of two algae, and by 67 and 200%, respectively, and one coral, by 20%.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Agronomy and Plant Breeding, College of Agriculture, Isfahan University of Technology, Isfahan, 84156-83111, Iran.
The increasing trend of salinization of agricultural lands represents a great threat to the growth of major crops. Hence, shedding light on the salt-tolerance capabilities of three environment-resilient medicinal species from the Apiaceae, i.e.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
School of Chemistry, Liaoning University, Shenyang 110036, China. Electronic address:
In this study, the interactions between three quaternary ammonium salt (QAS) cationic surfactants with different branched-chain lengths (TMBAC, TEBAC, and TBBAC) and DNA are investigated by UV-vis absorption, fluorescence and CD spectroscopy, viscosity method, and gel electrophoresis. Berberine hydrochloride (BR) is utilized as a fluorescent probe. The three interaction modes and strengths are compared.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!