Organization of Nano-disks of Laponite® in Soft Colloidal Systems

Colloidal systems in soils

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100168050 ◽

1994 ◽

Vol 52 ◽

pp. 64-65

Author(s):

J. Thieme ◽

J. Niemeyer ◽

P. Guttman

Keyword(s):

Clay Minerals ◽

Polymeric Materials ◽

Spatial Arrangement ◽

High Specific Surface Area ◽

Turnover Rates ◽

Colloidal Systems ◽

Chemical Conditions ◽

Aggregation Phenomena ◽

Iron And Manganese ◽

Soil Colloids

In soil science the fraction of colloids in soils is understood as particles with diameters smaller than 2μm. Clay minerals, aquoxides of iron and manganese, humic substances, and other polymeric materials are found in this fraction. The spatial arrangement (microstructure) is controlled by the substantial structure of the colloids, by the chemical composition of the soil solution, and by thesoil biota. This microstructure determines among other things the diffusive mass flow within the soils and as a result the availability of substances for chemical and microbiological reactions. The turnover of nutrients, the adsorption of toxicants and the weathering of soil clay minerals are examples of these surface mediated reactions. Due to their high specific surface area, the soil colloids are the most reactive species in this respect. Under the chemical conditions in soils, these minerals are associated in larger aggregates. The accessibility of reactive sites for these reactions on the surface of the colloids is reduced by this aggregation. To determine the turnover rates of chemicals within these aggregates it is highly desirable to visualize directly these aggregation phenomena.

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Disintegrating polymer multilayers to jump-start colloidal micromotors

Nanoscale ◽

10.1039/c8nr08071b ◽

2019 ◽

Vol 11 (2) ◽

pp. 733-741 ◽

Cited By ~ 4

Author(s):

Marina Fernández-Medina ◽

Xiaomin Qian ◽

Ondrej Hovorka ◽

Brigitte Städler

Keyword(s):

Colloidal Systems ◽

Autonomous Mobility

Colloidal systems with autonomous mobility are attractive alternatives to static particles for diverse applications.

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Tunable thermo-reversible bicontinuous nanoparticle gel driven by the binary solvent segregation

Nature Communications ◽

10.1038/s41467-020-20701-3 ◽

2021 ◽

Vol 12 (1) ◽

Cited By ~ 2

Author(s):

Yuyin Xi ◽

Ronald S. Lankone ◽

Li-Piin Sung ◽

Yun Liu

Keyword(s):

Phase Separation ◽

Domain Size ◽

Binary Solvent ◽

Colloidal Systems ◽

Colloidal Assembly ◽

Structures And Properties ◽

Wide Range ◽

Equilibrium Process ◽

Equilibrium Structures ◽

Non Equilibrium

AbstractBicontinuous porous structures through colloidal assembly realized by non-equilibrium process is crucial to various applications, including water treatment, catalysis and energy storage. However, as non-equilibrium structures are process-dependent, it is very challenging to simultaneously achieve reversibility, reproducibility, scalability, and tunability over material structures and properties. Here, a novel solvent segregation driven gel (SeedGel) is proposed and demonstrated to arrest bicontinuous structures with excellent thermal structural reversibility and reproducibility, tunable domain size, adjustable gel transition temperature, and amazing optical properties. It is achieved by trapping nanoparticles into one of the solvent domains upon the phase separation of the binary solvent. Due to the universality of the solvent driven particle phase separation, SeedGel is thus potentially a generic method for a wide range of colloidal systems.

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Bacterial streamers as colloidal systems: Five grand challenges

Journal of Colloid and Interface Science ◽

10.1016/j.jcis.2021.02.102 ◽

2021 ◽

Vol 594 ◽

pp. 265-278

Author(s):

Udita U. Ghosh ◽

Hessein Ali ◽

Ranajay Ghosh ◽

Aloke Kumar

Keyword(s):

Colloidal Systems ◽

Grand Challenges

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Towards a methodology for the characterisation of the fabric of wet clays using X-ray scattering

E3S Web of Conferences ◽

10.1051/e3sconf/20199201005 ◽

2019 ◽

Vol 92 ◽

pp. 01005

Author(s):

Georgios Birmpilis ◽

Reza Ahmadi-Naghadeh ◽

Jelke Dijkstra

Keyword(s):

Materials Science ◽

Measurement Techniques ◽

Invasive Technique ◽

Colloidal Systems ◽

Characteristic Distance ◽

X Ray ◽

Hydrophobic Coating ◽

X Ray Scattering ◽

Wide Range ◽

Ray Scattering

X-ray scattering is a promising non-invasive technique to study evolving nano- and micromechanics in clays. This study discusses the experimental considerations and a successful method to enable X-ray scattering to study clay samples at two extreme stages of consolidation. It is shown that the proposed sample environment comprising flat capillaries with a hydrophobic coating can be used for a wide range of voids ratios ranging from a clay suspension to consolidated clay samples, that are cut from larger specimens of reconstituted or natural clay. The initial X-ray scattering results using a laboratory instrument indicate that valuable information on, in principal evolving, clay fabric can be measured. Features such as characteristic distance between structural units and particle orientations are obtained for a slurry and a consolidated sample of kaolinite. Combined with other promising measurement techniques from Materials Science the proposed method will help advance the contemporary understanding on the behaviour of dense colloidal systems of clay, as it does not require detrimental sample preparation

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