The deposition of colloidal particles from a sessile drop of a volatile suspension subject to particle adsorption and coagulation

AbstractThe coupled transport of pollutants that are adsorbed to colloidal particles has always been a major topic for environmental sciences due to many unfavorable effects on soils and groundwater. This laboratory column study was conducted under saturated moisture conditions to compare the hydrophobic character of the suspended and mobilized colloids in the percolates released from a wettable subsoil and a water repellent topsoil. Both soils with different organic matter content were analyzed for wettability changes before and after leaching using sessile drop contact angles as well as water and ethanol sorptivity curves, summarized as repellency index. Hydrophobicity of the effluent suspensions was assessed using the C18 adsorption method. Water repellency level of the repellent soil decreased after leaching but remained on a lower level of water repellency, while, the wettable soil remained wettable. The leached colloids from the repellent soil were predominantly hydrophilic and the percentage of the hydrophobic colloid fraction in the effluent did not systematically changed with time. Total colloid release depended on soil carbon stock but not on soil wettability. Our results suggest that due to the respective character of transported colloids a similar co-transport mechanism for pollutants may occur which does not depend explicitly on soil wettability of the releasing horizon, but could be more affected by total SOM content. Further studies with a wider range of soils are necessary to determine if the dominant hydrophilic character of leached colloids is typical. Due to the mostly hydrophilic colloid character we conclude also that changes in wettability status, i.e. of wettable subsoil horizons due to the leachate, may not necessarily occur very fast, even when the overlaying topsoil is a repellent soil horizon with a high organic matter content.

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THE MODEL OF DRYING SESSILE DROP OF COLLOIDAL SOLUTION

Modern Physics Letters B ◽

10.1142/s0217984911026280 ◽

2011 ◽

Vol 25 (15) ◽

pp. 1303-1310 ◽

Cited By ~ 8

Author(s):

I. V. VODOLAZSKAYA ◽

YU. YU. TARASEVICH

Keyword(s):

Colloidal Particles ◽

Colloidal Solution ◽

Sessile Drop ◽

Temporal Evolution ◽

Volume Fraction ◽

Colloidal Suspension ◽

Phase Dynamics ◽

Gel Phase ◽

Horizontal Substrate ◽

Physical Quantities

We have proposed and investigated a model of drying colloidal suspension drop placed onto a horizontal substrate in which the sol to gel phase transition occurs. The temporal evolution of volume fraction of the solute and the gel phase dynamics were obtained from numerical simulations. Our model takes into account the fact that some physical quantities are dependent on volume fraction of the colloidal particles.

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Evaporative Deposition of Bacteria and Microspheres on Mica from a Sessile Drop: The Use of Surface Conditioning in a Laboratory Atmosphere to Control Drop Spreading and Particle Deposition Patterns

MRS Proceedings ◽

10.1557/proc-1273-mm03-03 ◽

2010 ◽

Vol 1273 ◽

Author(s):

Joan E Curry ◽

Raina M. Maier ◽

Theresa A. Norris ◽

Kyle Fisher Baughman

Keyword(s):

Contact Angle ◽

Particle Deposition ◽

Colloidal Particles ◽

Colloidal Particle ◽

Sessile Drop ◽

Mica Surface ◽

Deposition Pattern ◽

Deposition Patterns ◽

Drop Spreading ◽

Surface Conditioning

AbstractEvaporative deposition from a sessile drop is an appealing way to deposit materials on a surface due to the simplicity of the technique. In this work we deposit aqueous solutions of two types of colloidal particles, namely bacteria and microspheres, on mica. We show that by controlling the extent of initial drop spreading through subtle changes in surface conditioning caused by exposure to the laboratory atmosphere in a laminar flow hood it is possible to systematically vary the particle deposition patterns. On freshly cleaved mica the contact angle of water is < 5°. Drops of bacterial and microsphere solutions deposited on freshly cleaved mica spread to cover a large surface area. Drying occurs through pinning and depinning events leaving a series of colloidal particle rings. We found in our laboratory that the contact angle of water on mica exposed to a constant flow of filtered laboratory air in a laminar flow hood gradually increases with time. For drops of both bacterial and microsphere solutions there is a corresponding decrease in the extent of drop spreading with increasing exposure of the mica surface to laboratory air. This results in a profound change in the colloidal particle deposition pattern. Short exposures of minutes to hours are enough to decrease spreading and affect the resulting deposition pattern. For our longest mica surface exposure times (months to 1 year) the contact angle of water reaches values near 20°. Spreading of the bacterial and microsphere drops is substantially decreased. A portion of the colloidal particles are deposited in an outer deposition ring which marks the extent of drop spreading and the remainder of the particles are deposited in the drop interior as a honeycomb or cellular film. The fraction of the drop residue covered with the cellular film increases with particle concentration as well as the length of time the mica is exposed to the laboratory atmosphere. This work shows that evaporative deposition on mica is very sensitive to surface conditioning through atmospheric exposure and also suggests that particle deposition patterns can be tuned by small changes in drop spreading.

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Simulations of the dynamic deposition of colloidal particles from a volatile sessile drop

Journal of Colloid and Interface Science ◽

10.1016/j.jcis.2018.04.054 ◽

2018 ◽

Vol 525 ◽

pp. 282-290 ◽

Cited By ~ 5

Author(s):

Anna Zigelman ◽

Ofer Manor

Keyword(s):

Colloidal Particles ◽

Sessile Drop

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Ultrastructure of Lymphatic Capillaries in the Transport of Colloidal Particles

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100060945 ◽

1967 ◽

Vol 25 ◽

pp. 186-187

Author(s):

L. V. Leak ◽

J. F. Burke

Keyword(s):

Connective Tissue ◽

Colloidal Particles ◽

Ultrastructural Level ◽

Vital Role ◽

Time Intervals ◽

Thorium Dioxide ◽

Lymphatic Capillary ◽

Tissue Area ◽

Rapid Removal ◽

Tissue Fluids

The vital role played by the lymphatic capillaries in the transfer of tissue fluids and particulate materials from the connective tissue area can be demonstrated by the rapid removal of injected vital dyes into the tissue areas. In order to ascertain the mechanisms involved in the transfer of substances from the connective tissue area at the ultrastructural level, we have injected colloidal particles of varying sizes which range from 80 A up to 900-mμ. These colloidal particles (colloidal ferritin 80-100A, thorium dioxide 100-200 A, biological carbon 200-300 and latex spheres 900-mμ) are injected directly into the interstitial spaces of the connective tissue with glass micro-needles mounted in a modified Chambers micromanipulator. The progress of the particles from the interstitial space into the lymphatic capillary lumen is followed by observing tissues from animals (skin of the guinea pig ear) that were injected at various time intervals ranging from 5 minutes up to 6 months.

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Deposited emulsion particles in the pores of aluminum oxide film

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100109392 ◽

1978 ◽

Vol 36 (1) ◽

pp. 450-451

Author(s):

Michio Ashida ◽

Yasukiyo Ueda

Keyword(s):

Oxide Film ◽

Acid Solution ◽

Barrier Layer ◽

Colloidal Particles ◽

Oxalic Acid Solution ◽

Anodic Oxide ◽

Anodic Oxide Film ◽

Carbon Replica ◽

Sectioning Method ◽

Thin Sectioning

An anodic oxide film is formed on aluminum in an acidic elecrolyte during anodizing. The structure of the oxide film was observed directly by carbon replica method(l) and ultra-thin sectioning method(2). The oxide film consists of barrier layer and porous layer constructed with fine hexagonal cellular structure. The diameter of micro pores and the thickness of barrier layer depend on the applying voltage and electrolyte. Because the dimension of the pore corresponds to that of colloidal particles, many metals deposit in the pores. When the oxide film is treated as anode in emulsion of polyelectrolyte, the emulsion particles migrate onto the film and deposit on it. We investigated the behavior of the emulsion particles during electrodeposition.Aluminum foils (99.3%) were anodized in either 0.25M oxalic acid solution at 30°C or 3M sulfuric acid solution at 20°C. After washing with distilled water, the oxide films used as anode were coated with emulsion particles by applying voltage of 200V and then they were cured at 190°C for 30 minutes.

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COUPLING OF COLLOIDAL PARTICLES AND RECOILLESS FRACTION

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1976655 ◽

1976 ◽

Vol 37 (C6) ◽

pp. C6-273-C6-276

Author(s):

H. J. ÜBELHACK ◽

F. H. WITTMANN

Keyword(s):

Colloidal Particles ◽

Recoilless Fraction

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How to use alum with cationic dispersed rosin size

TAPPI Journal ◽

10.32964/tj15.5.331 ◽

2016 ◽

Vol 15 (5) ◽

pp. 331-335 ◽

Cited By ~ 3

Author(s):

LEBO XU ◽

JEREMY MYERS ◽

PETER HART

Keyword(s):

Zeta Potential ◽

Colloidal Particles ◽

Streaming Potential ◽

Excessive Amount ◽

Paper Machine ◽

Optimum Amount ◽

Potential Measurement ◽

Streaming Current ◽

Wide Range ◽

Laboratory Results

Retention of cationic dispersed rosin size was studied via turbidity measurements on stock filtrate with different alum and dispersed rosin size dosages. Stock charge characteristics were analyzed using both an analysis of charge demand determined via a streaming current detector and an evaluation of zeta potential of the fibers by streaming potential measurement. The results indicated that an optimum amount of alum existed such that good sizing retention was maintained throughout a wide range of dispersed rosin size dosages. However, when an excessive amount of alum was used and fines and colloidal particles were transitioned from anionic to cationic, the cationic size retention was reduced. Laboratory results were confirmed with a paper machine trial. All data suggested that a stock charge study was necessary to identify optimal alum dosage for a cationic dispersed rosin sizing program.

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