The experimental dependences of viscoelasticity modulus and phase angle as a function of frequency for various C 14EO8 concentrations at the critical micelle concentration (cmc) of 7 micromol/L and far above the cmc (up to 70 x cmc) were studied using the buoyant bubble profile analysis method. With increasing C14EO8 concentration the viscoelasticity modulus decreases and the phase angle increases. At the highest surfactant concentrations, the phase angle was more than 45 degrees . For the theoretical description of the equilibrium surface tension isotherm and the limiting elasticity modulus, a combined theoretical model was used considering surface reorientation and molecular compression. To analyze the experimental dependencies of the viscoelasticity modulus and phase angle on frequency, a model proposed by Joos for fast micellar kinetics was applied. This theory agrees well with the experimental data of the viscoelasticity modulus obtained for all concentrations of the studied nonionic surfactant C14EO8.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/la704058y | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Mechanical Wear of Degraded Articular Cartilage.
Ann Biomed Eng
January 2025
School of Mechanical Engineering, Purdue University, West Lafayette, IN, 47907, USA.
Purpose: To evaluate the mechanical wear of cartilage with different types of degradation.
Methods: Bovine osteochondral explants were treated with interleukin-1β (IL-1β) to mimic inflammatory conditions, with chondroitinase ABC (ChABC) to specifically remove glycosaminoglycans (GAGs), or with collagenase to degrade the collagen network during 5 days of culture. Viscoelastic properties of cartilage were characterized via indentation.
Piezoresistive Cantilever Microprobe with Integrated Actuator for Contact Resonance Imaging.
Sensors (Basel)
January 2025
Institute of Semiconductor Technology (IHT), Technische Universität Braunschweig, Hans-Sommer-Straße 66, 38106 Braunschweig, Germany.
A novel piezoresistive cantilever microprobe (PCM) with an integrated electrothermal or piezoelectric actuator has been designed to replace current commercial PCMs, which require external actuators to perform contact-resonance imaging (CRI) of workpieces and avoid unwanted "forest of peaks" observed at large travel speed in the millimeter-per-second range. Initially, a PCM with integrated resistors for electrothermal actuation (ETA) was designed, built, and tested. Here, the ETA can be performed with a piezoresistive Wheatstone bridge, which converts mechanical strain into electrical signals by boron diffusion in order to simplify the production process.
View Article and Find Full Text PDFPly Optimization of Composite Laminates for Processing-Induced Deformation and Buckling Eigenvalues Based on Improved Genetic Algorithm.
Materials (Basel)
January 2025
School of Aeronautic Science and Engineering, Beihang University, Beijing 100191, China.
The structure of thermoset composite laminated plates is made by stacking layers of plies with different fiber orientations. Similarly, the stiffened panel structure is assembled from components with varying ply configurations, resulting in thermal residual stresses and processing-induced deformations (PIDs) during manufacturing. To mitigate the residual stresses caused by the geometric features of corner structures and the mismatch between the stiffener-skin ply orientations, which lead to PIDs in composite-stiffened panels, this study proposes a multi-objective stacking optimization strategy based on an improved adaptive genetic algorithm (IAGA).
View Article and Find Full Text PDFEffects of laminarin and ferulic acid on pasting, rheology, freeze-thaw stability and in vitro digestion of cassava starch.
Int J Biol Macromol
January 2025
College of Tourism and Cuisine, Yangzhou University, Yangzhou 225127, China. Electronic address:
This study aimed to investigate the effects of laminarin (LA) and ferulic acid (FA) on the gelatinization, rheological properties, freeze-thaw stability, and digestibility of cassava starch (CS). The results indicated that LA increased the peak viscosity, trough viscosity, final viscosity, storage modulus, and loss modulus of CS, while decreasing the breakdown viscosity. Conversely, FA exerted opposite effects.
View Article and Find Full Text PDFPhysicochemical and rheological characterization of plant-based proteins, pectin, and chitin nanofibers for developing high internal phase Pickering emulsions as potential fat alternatives.
Food Chem
January 2025
Department of Nutritional Sciences, University of Connecticut, Storrs, CT, 06269, United States. Electronic address:
This study evaluated the properties of lentil protein, pea protein, quinoa protein, and soy protein as natural nanoparticle stabilizers and their interactions with pectin and chitin nanofiber in preparing high internal phase Pickering emulsions (HIPPEs). The globular plant proteins interact with polysaccharides through hydrogen bonding and electrostatic interactions, transforming the structure into complex morphologies, including fibrous and elliptical shapes. These complex nanoparticles exhibited enhanced thermal decomposition stability, and the HIPPEs constructed by them demonstrated significantly improved apparent viscosity and elastic modulus, with a yield stress of 931.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!