The in situ rheology of polymeric solutions has been studied experimentally in etched silicon micromodels which are idealizations of porous media. The rectangular channels in these etched networks have dimensions typical of pore sizes in sandstone rocks. Pressure drop/flow rate relations have been measured for water and non-Newtonian hydrolyzed-polyacrylamide (HPAM) solutions in both individual straight rectangular capillaries and in networks of such capillaries. Results from these experiments have been analyzed using pore-scale network modeling incorporating the non-Newtonian fluid mechanics of a Carreau fluid. Quantitative agreement is seen between the experiments and the network calculations in the Newtonian and shear-thinning flow regions demonstrating that the 'shift factor,'alpha, can be calculated a priori. Shear-thickening behavior was observed at higher flow rates in the micromodel experiments as a result of elastic effects becoming important and this remains to be incorporated in the network model.
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http://dx.doi.org/10.1016/j.jcis.2005.09.012 | DOI Listing |
Heliyon
January 2025
Institute of Mathematics, Henan Academy of Sciences, Zhengzhou, 450046, China.
This study examines the behavior of the Casson nanofluid bioconvection flow around a spinning disc under various influences, including gyrotactic microorganisms, multiple slips, and thermal radiation. Notably, it accounts for the reversible nature of the flow and incorporates the esterification process. The aim of this study is to investigate the influence of reversible chemical reactions on the flow behavior of a Casson nanofluid in the presence of bioconvective microorganisms over a spinning disc.
View Article and Find Full Text PDFComput Methods Programs Biomed
January 2025
Dalian University of Technology Affiliated Central Hospital, Dalian 116024, China.
Objective: The study aims to elucidate the mechanisms underlying plaque growth by analyzing the variations in hemodynamic parameters within the plaque region of patients' carotid arteries before and after the development of atherosclerotic lesions.
Methods: The study enrolls 25 patients with common carotid artery stenosis and 25 with tandem carotid artery stenosis. Based on pathological analysis, three-dimensional models of the actual blood vessels before and after the lesion are constructed for two patients within a two-year period.
Int J Biol Macromol
January 2025
National Research and Development Center of Freshwater Fish Processing, College of Life Sciences, Jiangxi Normal University, Nanchang, Jiangxi 330022, China. Electronic address:
Tannin is the main naturally occurring phytochemicals in Rubus chingii Hu with poor digestive stability and low bioavailability. In this study, oil-in-water (O/W) and water-in-oil (W/O) emulsion gels encapsulating Rubus chingii Hu ellagitannins (RCHT) were fabricated and their structure, rheology, stability, in vitro digestion and in vivo metabolism were characterized. The W/O emulsion gel showed smaller particle size, better pH stability, thermal stability, centrifugal stability and storage stability.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
Department of Food Engineering and Technology, Tezpur University, Napaam, Sonitpur, Tezpur, Assam, India. Electronic address:
Microwave-assisted extraction of pectin from Dillenia indica (DI) fruit was optimized using Box-Behnken design to maximize yield and quality. Parameters such as solid:solvent (1:10-1:30), microwave power (200-600 W), and extraction time (4-10 min) were varied to determine the optimal conditions. Through experimentation, the optimized extraction parameters were identified as 1:23.
View Article and Find Full Text PDFElectromagn Biol Med
January 2025
Department of Applied Mathematics, University of Calcutta, Kolkata, India.
The current investigation explores tri-hybrid mediated blood flow through a ciliary annular model, designed to emulate an endoscopic environment. The human circulatory system, driven by the metachronal ciliary waves, is examined in this study to understand how ternary nanoparticles influence wave-like flow dynamics in the presence of interfacial nanolayers. We also analyze the effect of an induced magnetic field on Ag-Cu-/blood flow within the annulus, focusing on thermal radiation, heat sources, buoyancy forces and ciliary motion.
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