We present a model for the theoretical description of the electric double layer of realistic salt-free colloidal suspensions. This kind of systems consist of aqueous suspensions deionized maximally without any electrolyte added during the preparation, in which the only ions present can be (i) the added counterions that counterbalance the surface charge, (ii) the H(+) and OH(-) ions from water dissociation, and (iii) the ions produced by the atmospheric CO2 contamination. Our theory is elaborated in the framework of the classical Poisson-Boltzmann theory, the spherical cell model approach, and the appropriate local equilibrium reactions, and it also includes an efficient mathematical treatment for dealing with the resulting integro-differential equations. We have applied it to the study of the surface electric potential in a wide range of volume fraction and surface charge density values in a variety of cases. The numerical results show that it is necessary to consider the water dissociation influence for volume fractions lower than approximately 10(-2), whereas the atmospheric contamination, if the suspensions are open to the atmosphere, is important in the region of phi<10(-1). The present work sets the basis for theoretical models concerning the equilibrium phase diagram, electrokinetics, and rheology of such systems.
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Int J Biol Macromol
January 2025
Beijing Key Laboratory of Functional Food from Plant Resources, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China. Electronic address:
This study investigated the dynamic changes in legume starches (common vetch, mung bean, and pea) during gelatinization. All three starches displayed a similar pattern: water absorption and swelling at lower temperatures (50-65 °C), structural rupture at medium temperatures (65-75 °C), and melting/reorganization at higher temperatures (75-90 °C). Gelatinization likely starts with internal structural dissociation, as evidenced by the weakening of the double helix structure and decreasing order observed throughout the process.
View Article and Find Full Text PDFFood Chem
January 2025
School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, China. Electronic address:
In this study, the absolute electrostatic charge of myofibrillar protein (MP) was substantially increased by protein-glutaminase (PG) treatment, which was a critical step for achieving the dissociation and solubility of MP under low salt condition. The PG-treated MP exhibited the capacity to form thermo-reversible gels that could be melted through heating and subsequently reformed into a stable gel structure upon refrigeration. The results of SDS-PAGE further revealed that the levels of soluble monomeric myosin and actin in the supernatant of deamidated MP (DMP) gels were markedly elevated, and confirmed the increased formation of intermolecular disulfide bond between myosin and actin.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
December 2024
Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), State Key Laboratory of Chemical Engineering, Haihe Laboratory of Sustainable Chemical Transformations, Tianjin Key Laboratory of Applied Catalysis Science and Engineering, School of Chemical Engineering & Technology, Tianjin University, Tianjin, 300072, P. R. China.
CO hydrogenation to methanol using green hydrogen derived from renewable resources provides a promising method for sustainable carbon cycle but suffers from high selectivity towards byproduct CO. Here, we develop an efficient PdZn-ZnO/TiO catalyst by engineering lattice dislocation structures of TiO support. We discover that this modification orders irregularly arranged atoms in TiO to stabilize crystal lattice, and consequently weakens electronic interactions with supported active phases.
View Article and Find Full Text PDFGenes Cells
January 2025
Laboratory for Systems Molecular Ethology, RIKEN Center for Brain Science, Saitama, Japan.
Single-cell RNA-sequencing (scRNA-seq) is a powerful method to comprehensively overlook gene expression profiles of individual cells in various tissues, providing fundamental datasets for classification of cell types and further functional analyses. Here we adopted scRNA-seq analysis for the zebrafish olfactory sensory neurons which respond to water-borne odorants and pheromones to elicit various behaviors crucial for survival and species preservation. Firstly, a single-cell dissociation procedure of the zebrafish olfactory rosettes was optimized by using cold-active protease, minimizing artifactual neuronal activation.
View Article and Find Full Text PDFAnal Chim Acta
January 2025
Tianjin Key Laboratory on Technologies Enabling Development of Clinical Therapeutics and Diagnostics, School of Pharmacy, Tianjin Medical University, 300070, Tianjin, China. Electronic address:
Background: Many of the ligand affinity analyses are presented in water environment, and the hydrophilic solution such as methanol is used for dissociating the bound compounds. The obtained dissociation solution needs to be concentrated for improving the sensitivity of the assay. However, it is not good for the analysis of hydrophobic and volatile compounds such as coumarins.
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