Poly (acrylic ester) hydrogel materials were widely used in intraocular lens and contact lens because of their excellent optical performance and biocompatibility. In this paper, the bulk copolymerization behavior of hydrophilic hydroxyethyl methacrylat with hydrophobic methyl metharylate was studied; and the optical performance, calcium deposits, equilibrium water content of polymers and its hydrogels obtained by different ratios of monomers were systematically investigated. The experimental results showed that the average light transmittance and the equilibrium water content of the obtained hydrogels increased with the increasing of the hydrophilic monomer content from 0 to 100%; however, the hardness decreased. The highest light transmittance reached 97% and the hardness of Shore A fell from 92 to 25, the equilibrium water content of hydrogel increased from 16% to 64%. The absorbent capacity of copolymers reduced with the adding of cross-linking monomer. When m(hydrophilic monomer): m(hydrophobic monomer) = 90 : 10, the combination property of the polymer and its hydrogel obtained is optimum.
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Med Phys
January 2025
OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany.
Background: Previous studies have shown that in-beam magnetic resonance imaging (MRI) can be used to visualize a proton beam during the irradiation of liquid-filled phantoms. The beam energy- and current-dependent local image contrast observed in water was identified to be predominantly caused by beam-induced buoyant convection and associated flow effects. Besides this flow dependency, the MR signal change was found to be characterized by a change in the relaxation time of water, hinting at a radiochemical contribution, which was hypothesized to lie in oxygen depletion-evoked relaxation time lengthening.
View Article and Find Full Text PDFJ Phys Chem A
January 2025
Center for Satellite Application on Environment, Ministry of Ecology and Environment, Beijing 100094, China.
The edge structures of carbonaceous materials exhibit temperature-dependent behavior on the atomic scale, with variations in the relative ratios of zigzag, reconstructed 5-7 zigzag (ZZ57), and armchair edges observed at different temperatures. Nevertheless, the mechanisms underlying the interconversion of these edge structures and the influence of the surrounding metals remain unclear. This study investigates the reconstruction and reversible transformation processes of ZZ57 edge structures in carbon materials and examines the effects of different metal atoms (Na, K, and Ca) by using density functional theory.
View Article and Find Full Text PDFBiopolymers
March 2025
Guangxi Key Laboratory of Natural Polymer Chemistry and Physics, College of Chemistry and Materials, Nanning Normal University, Nanning, People's Republic of China.
The crosslinked porous corn starch was prepared by two steps: the native corn starch was hydrolyzed by α-amylase and glucoamylase, then the porous corn was crosslinked by sodium trimetaphosphate (STMP). The morphology and size of granules, spherulites, crystal type, molecular structure, swelling properties, thermal stability and adsorption properties of the crosslinked porous starch were investigated. The results indicated that a lot of holes formed in the porous starch, and the particle size of starch granules decreased.
View Article and Find Full Text PDFLangmuir
January 2025
Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, United States.
We demonstrate, using non-equilibrium molecular dynamics simulations, that lipid membrane capacitance varies with surface charge accumulation linked to membrane shape and curvature changes. Specifically, we show that lipid membranes exhibit a hysteretic response when exposed to oscillatory electric fields. The electromechanical coupling in these membranes leads to hysteretic buckling, in which the membrane can spontaneously buckle in one of two distinct directions along the electric field, even for the same ionic charge accumulation at the water-membrane interface.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
January 2025
Grupo de Investigación Materiales Con Impacto (Mat&Mpac), Facultad de Ciencias Básicas, Universidad de Medellín, Carrera 87 No. 30-65, 050026, Medellín, Colombia.
This study shows the efficiency of WH-C450, an adsorbent obtained from water hyacinth (WH) biomass, in the removal of sulfamethoxazole (SMX) from aqueous solutions. The process involves calcination of WH at 450 °C to produce an optimal adsorbent material capable of removing up to 73% of SMX and maximum SMX adsorption capacity of 132.23 mg/g.
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