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Laurie S Sanderso - One of the best experts on this subject based on the ideXlab platform.

  • Models of fluid interaction with oral structures in suspension-feeding fishes.
    2018
    Co-Authors: Hannah Ooks, Gra E. Haines, Laurie S Sanderso
    Abstract:

    Coronal (frontal) sections illustrating flow patterns during (A) Crossflow Filtration in a species such as the blue tilapia (Oreochromis aureus, Cichlidae) [16], and (B) vortical cross-step Filtration in the paddlefish (Polyodon spathula, Polyodontidae) [8]. In both (A) and (B), mainstream flow passes parallel or tangential to the filter formed by the branchial arches (ba) and the gill rakers (gr), while filtrate passes between the gill rakers and across the gill filaments (gf) for gas exchange before exiting via the opercular cavities beneath the operculum (op). In (B), the interaction of Crossflow with the backward-facing steps formed by the branchial arches generates sustained vortices in the slots (sl) between the branchial arches. The first gill slot extends from the suspensorium in the oral roof and the dentary to the first branchial arch. Illustration by Virginia Greene/virginiagreeneillustration.com.

  • Hypothesized Filtration mechanisms in suspension-feeding fishes.
    2018
    Co-Authors: Hannah Ooks, Gra E. Haines, Laurie S Sanderso
    Abstract:

    (A) Dead-end sieving with flow perpendicular to the filter. Small particles exit while large particles clog pores [6]. (B) Hydrosol Filtration with flow perpendicular to the filter. Small particles that are retained on the sticky filter may clog pores [6]. (C) Crossflow Filtration with flow parallel to the filter. Inertial lift and shear-induced diffusion cause particle migration away from the filter [7]. (D) Vortical cross-step Filtration with flow approximately parallel (tangential) to the filter, which consists of backward-facing steps forming d-type ribs [8]. Inertial lift and shear-induced diffusion cause particle migration away from the filter. Smallest particles are concentrated and transported by vortices. Enlargement of cross-step filter (box on right), showing groove aspect ratio (wh-1, slot width divided by rib height) and zones (1, 2, 3) inside slot. Circles represent particles of different diameters, with smallest circles representing the smallest particles. Illustration by M. Carly Lin.

  • computational fluid dynamics of fish gill rakers during Crossflow Filtration
    Bulletin of Mathematical Biology, 2012
    Co-Authors: A Y Chee, Samso Cheung, Tienchieh Hung, Raul H Piedrahita, Laurie S Sanderso
    Abstract:

    We study Crossflow Filtration mechanisms in suspension-feeding fishes using computational fluid dynamics to model fluid flow and food particle movement in the vicinity of the gill rakers. During industrial and biological Crossflow Filtration, particles are retained when they remain suspended in the mainstream flow traveling across the filter surface rather than traveling perpendicularly to the filter. Here we identify physical parameters and hydrodynamic processes that determine food particle movement and retention inside the fish oral cavity. We demonstrate how five variables affect flow patterns and particle trajectories: (1) flow speed inside the fish oral cavity, (2) incident angle of the flow approaching the filter, (3) dimensions of filter structures, (4) particle size, and (5) particle density. Our study indicates that empirical experiments are needed to quantify flow parameters inside the oral cavity, and morphological research is needed to quantify dimensions of the filter apparatus such as gill rakers, the gaps between rakers, and downstream barriers. Ecological studies on suspension-feeding fishes are also needed to quantify food particle size and density, as these variables can affect particle retention due to hydrodynamic processes during Crossflow Filtration.

  • mucus function and Crossflow Filtration in a fish with gill rakers removed versus intact
    The Journal of Experimental Biology, 2007
    Co-Authors: Jennife C Smith, Laurie S Sanderso
    Abstract:

    Filtration mechanisms are known for only two species of suspension-feeding tilapia, each of which relies on a different method of particle retention. We used high-speed video endoscopy to assess whether a third species of tilapia, Oreochromis aureus , with gill rakers intact as well as surgically removed, uses mucus in the oropharyngeal cavity for hydrosol Filtration or uses Crossflow Filtration to retain particles during suspension feeding. Although a large amount of mucus was visible during feeding with rakers intact, particles were rarely retained in the mucus. The hypothesis that the presence of mucus results in particle entrapment by hydrosol Filtration is rejected for O. aureus . Rather than functioning as a sticky filter, mucus is proposed to function in this species to regulate the loss of water between the rakers and between the anterior branchial arches, increasing Crossflow speed and thereby increasing the inertial lift force that transports particles radially away from the arches. Gill raker removal resulted in an almost complete lack of observable mucus in the oropharyngeal cavity, probably due to the removal of mucus-secreting cells attached to the gill rakers. However, endoscopic videotapes showed that Crossflow Filtration continued to operate in the absence of gill rakers and mucus, indicating that the surfaces of the branchial arches play an important role in Crossflow Filtration.

  • feeding mechanisms in carp Crossflow Filtration palatal protrusions and flow reversals
    The Journal of Experimental Biology, 2003
    Co-Authors: Todd W Calla, Laurie S Sanderso
    Abstract:

    It has been hypothesized that, when engulfing food mixed with inorganic particles during benthic feeding, cyprinid fish use protrusions of tissue from the palatal organ to retain the food particles while the inorganic particles are expelled from the opercular slits. In Crossflow Filtration, the particle suspension is pumped parallel to the filter surface as filtrate exits through the filter pores, causing the suspension to become more concentrated as it travels downstream along the filter. We used high-speed video endoscopy to determine whether carp Cyprinus carpio use Crossflow Filtration and/or palatal protrusions during benthic feeding. We found that carp use Crossflow Filtration to concentrate small food particles in the pharyngeal cavity while expelling small dense inorganic particles through the opercular slits and via spits. Our results suggest that, during feeding on small food particles, palatal protrusions serve a localized chemosensory function rather than a mechanical particle-sorting function. However, palatal protrusions did retain large food particles while large inorganic particles were spit anteriorly from the mouth. We also investigated whether flow is continuous and unidirectional during suspension feeding in carp. As reported previously for ventilation in hedgehog skates and for certain industrial Crossflow Filtration applications, we observed that flow is pulsatile and bidirectional during feeding. These results have implications for hydrodynamic models of Crossflow Filtration in suspension-feeding fishes.

Benny D Freeman - One of the best experts on this subject based on the ideXlab platform.

  • polyamide interfacial composite membranes prepared from m phenylene diamine trimesoyl chloride and a new disulfonated diamine
    Journal of Membrane Science, 2012
    Co-Authors: Geoffrey M Geise, Benny D Freeman, Gwangsu Byun, James E Mcgrath
    Abstract:

    Abstract The influence of synthesis conditions (e.g., monomer concentration and membrane preparation protocol) on transport properties of polyamide thin-film composite (TFC) membranes prepared using m -phenylenediamine (MPD) and trimesoyl chloride (TMC) via interfacial polymerization is reported. For example, at 25 °C, NaCl rejection and permeate flux combinations of 99.6 ± 0.1% and 42 ± 3 L/(m 2  h), respectively, were achieved in Crossflow Filtration using a 2000 ppm aqueous solution of NaCl and a transmembrane pressure difference of 225 psi (15.5 bar). Additionally, a sulfone diamine, disulfonated bis[4-(3-aminophenoxy)phenyl]sulfone (S-BAPS), was used in place of MPD to prepare TFC membranes. The resulting membranes had low NaCl rejection but somewhat higher permeate flux than MPD/TMC membranes. These membranes had reduced chlorine tolerance compared to those prepared using MPD as the diamine.

  • effect of Crossflow testing conditions including feed ph and continuous feed Filtration on commercial reverse osmosis membrane performance
    Journal of Membrane Science, 2009
    Co-Authors: Elizabeth M Wagner, Alyson C Sagle, Mukul M. Sharma, Benny D Freeman
    Abstract:

    Crossflow Filtration experiments were performed to characterize the water flux and NaCl rejection of three commercial polyamide reverse osmosis (RO) membranes (LE and XLE from DOW Water Solutions and AG from GE Water and Process Technologies). Thorough cleaning of the Crossflow system, combined with following the manufacturer's recommended pretreatment and test conditions (i.e., feed pressure, flowrate, temperature, feed pH, and feed Filtration) resulted in measured performance values consistent with manufacturer benchmarks. Correction for the effect of concentration polarization also proved important. The influence of feed pH and continuous feed Filtration on water flux and salt rejection was characterized. While rejection was strongly affected by feed pH, water flux was essentially unaffected. Continuous Filtration of the feed led to higher water flux and lower salt rejection than that observed in experiments with unfiltered feed, suggesting fouling of the membrane surfaces by unfiltered feed. The flux and rejection of these three membranes obeyed a general tradeoff relation: membranes that exhibited higher flux had lower rejection and vice versa.

  • effect of Crossflow testing conditions including feed ph and continuous feed Filtration on commercial reverse osmosis membrane performance
    Journal of Membrane Science, 2009
    Co-Authors: Elizabeth M Wagner, Alyson C Sagle, Mukul M. Sharma, Benny D Freeman
    Abstract:

    Crossflow Filtration experiments were performed to characterize the water flux and NaCl rejection of three commercial polyamide reverse osmosis (RO) membranes (LE and XLE from DOW Water Solutions and AG from GE Water and Process Technologies). Thorough cleaning of the Crossflow system, combined with following the manufacturer's recommended pretreatment and test conditions (i.e., feed pressure, flowrate, temperature, feed pH, and feed Filtration) resulted in measured performance values consistent with manufacturer benchmarks. Correction for the effect of concentration polarization also proved important. The influence of feed pH and continuous feed Filtration on water flux and salt rejection was characterized. While rejection was strongly affected by feed pH, water flux was essentially unaffected. Continuous Filtration of the feed led to higher water flux and lower salt rejection than that observed in experiments with unfiltered feed, suggesting fouling of the membrane surfaces by unfiltered feed. The flux and rejection of these three membranes obeyed a general tradeoff relation: membranes that exhibited higher flux had lower rejection and vice versa.

  • crosslinked poly ethylene oxide fouling resistant coating materials for oil water separation
    Journal of Membrane Science, 2008
    Co-Authors: Hao Ju, Alyson C Sagle, Bryan D Mccloskey, Yuan Hsuan Wu, Victor A Kusuma, Benny D Freeman
    Abstract:

    Abstract Potential fouling reducing coating materials were synthesized via free-radical photopolymerization of aqueous solutions of poly(ethylene glycol) diacrylate (PEGDA). Crosslinked PEGDA (XLPEGDA) exhibited high water permeability and good fouling resistance to oil/water mixtures. Water permeability increased strongly with increasing the water content in the prepolymerization water mixture, going from 10 to 150 L μm/(m2 h bar) as prepolymerization water content increased from 60 to 80 wt.%. However, molecular weight cutoff decreased as water content increased. These materials were applied to polysulfone (PSF) UF membranes to form coatings on the surface of the PSF membranes. Oil/water Crossflow Filtration experiments showed that the coated PSF membranes had water flux values 400% higher than that of an uncoated PSF membrane after 24 h of operation, and the coated membranes had higher organic rejection than the uncoated membranes.

Yuewei Liu - One of the best experts on this subject based on the ideXlab platform.

C Fonade - One of the best experts on this subject based on the ideXlab platform.

  • enzyme transmission during Crossflow Filtration of yeast suspensions using gas liquid two phase flows
    Annals of the New York Academy of Sciences, 2003
    Co-Authors: Muriel Mercierboni, C Fonade
    Abstract:

    : The optimal conditions for recovery of an enzyme were determined using gas/liquid two-phase flows. When filtering the enzyme-only solution under single-phase flow conditions, severe fouling occurred. This fouling was manifest as a decline in flux to less than 2% of the initial water flux and a decline in protein concentration in the permeate to 30% of its initial value, during a five-hour Filtration period. When yeast cells were added under the same experimental conditions, enzyme transmission was maintained at 100% for the five-hour period and the enzyme mass flux was twofold higher. During gas-sparged microFiltration of the enzyme/yeast mixture in a permeate-recycling mode at the same liquid flow rate, gas/liquid slug flow strongly decreased the transmission of the enzyme (70% decrease), even though the permeate flux was improved (140% improvement). As a result, the mass flux of the enzyme was significantly reduced. However, with a bubble flow pattern, the permeate flux was 1.5 times higher and the transmission was maintained at a high level. The enzyme mass flux was then 25% higher when compared to single-phase flow Filtration conditions. During diaFiltration experiments with a bubble flow pattern, a 13% higher enzyme recovery was achieved.

  • comparison of three different systems used for flux enhancement application to Crossflow Filtration of yeast suspensions
    Desalination, 2002
    Co-Authors: Oma Alakoum, C Fonade, Muriel Mercierboni, Luhui Ding, Philippe Aptel, Michel Y Jaffri
    Abstract:

    The aim of this work is to characterize more accurately, through experimental or theoretical approaches, the hydrodynamics of three particular systems usually used for flux enhancement: shear-enhanced Filtration with a vibrating membrane module, gas/liquid two-phase flows and Dean vortices. The correlation between local hydrodynamics and permeate flux obtained during Crossflow Filtration of a yeast suspension under different operating conditions confirmed the importance of the wall shear stress in these three systems.

  • flux enhancement in Crossflow Filtration using an unsteady jet
    Journal of Membrane Science, 1997
    Co-Authors: C Maranges, C Fonade
    Abstract:

    This paper deals with the influence of a new type of unsteadiness in the flow on the permeate flux in Crossflow Filtration. A pneumatically controlled valve generates intermittent jets from the main flow leading to the formation of large vortices moving downstream along the tubular membrane. The experimental study was carried out by filtering a bentonite suspension through an ultraFiltration mineral membrane. Flux time measurements were taken under steady and unsteady operating conditions. The unsteadiness leads to a permeate flux more than two times higher than in the usual Filtration processes.

  • use of intermittent jets to enhance flux in Crossflow Filtration
    Journal of Membrane Science, 1993
    Co-Authors: G Arroyo, C Fonade
    Abstract:

    Abstract This paper deals with the influence of a new flow unsteadiness on the permeate fluxes in Crossflow Filtration. A pneumatically controlled valve generates intermittent jets from the main flow, causing the formation of large vortices moving downstream along the tubular membrane. The main results of the numerical calculation of such flows are given. The experimental study was carried out by filtering a bentonite suspension through an ultraFiltration mineral membrane. Time evolutions of flux were achieved in steady and unsteady operating conditions. Results concerning the influence and limits of the nozzle to tube diameter ratio and the jet velocities are discussed. The applicability of such an unsteady flow is examined with a view to effects on energy consumption and possible viscosity effects.

Todd W Calla - One of the best experts on this subject based on the ideXlab platform.

  • feeding mechanisms in carp Crossflow Filtration palatal protrusions and flow reversals
    The Journal of Experimental Biology, 2003
    Co-Authors: Todd W Calla, Laurie S Sanderso
    Abstract:

    It has been hypothesized that, when engulfing food mixed with inorganic particles during benthic feeding, cyprinid fish use protrusions of tissue from the palatal organ to retain the food particles while the inorganic particles are expelled from the opercular slits. In Crossflow Filtration, the particle suspension is pumped parallel to the filter surface as filtrate exits through the filter pores, causing the suspension to become more concentrated as it travels downstream along the filter. We used high-speed video endoscopy to determine whether carp Cyprinus carpio use Crossflow Filtration and/or palatal protrusions during benthic feeding. We found that carp use Crossflow Filtration to concentrate small food particles in the pharyngeal cavity while expelling small dense inorganic particles through the opercular slits and via spits. Our results suggest that, during feeding on small food particles, palatal protrusions serve a localized chemosensory function rather than a mechanical particle-sorting function. However, palatal protrusions did retain large food particles while large inorganic particles were spit anteriorly from the mouth. We also investigated whether flow is continuous and unidirectional during suspension feeding in carp. As reported previously for ventilation in hedgehog skates and for certain industrial Crossflow Filtration applications, we observed that flow is pulsatile and bidirectional during feeding. These results have implications for hydrodynamic models of Crossflow Filtration in suspension-feeding fishes.

  • Crossflow Filtration in suspension feeding fishes
    Nature, 2001
    Co-Authors: Laurie S Sanderso, A Y Chee, Jennife S Goodrich, Jenny D Graziano, Todd W Calla
    Abstract:

    Rows of comb-like or tufted gill rakers in the oral cavity of suspension-feeding fishes (for example, herring, anchovies and tilapia) have been thought to serve as (1) non-porous barriers that direct particle-laden water to the sticky oral roof, where particles are retained as water exits from the oral cavity, (2) conventional dead-end filters that sieve particles from water exiting between rakers, or (3) sticky filters that retain particles encountered by a hydrosol Filtration mechanism1,2,3,4,5,6. Here we present data from computational fluid dynamics and video endoscopy in suspension-feeding fish indicating that the rakers of three distantly related species function instead as a Crossflow filter7,8. Particles are concentrated inside the oral cavity as filtrate exits between the rakers, but particles are not retained on the rakers. Instead, the high-velocity Crossflow along the rakers carries particles away from the raker surfaces and transports the particles towards the oesophagus. This Crossflow prevents particles from clogging the gaps between the rakers, and solves the mystery of particle transport from the rakers to the oesophagus.