Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Coagulation01:06

Coagulation

357
Colloidal solids are solid particles suspended in solution. They are usually negatively charged, attracting a compact primary layer of positively charged ions, which attract more counterions to form an electrical double layer. Electrostatic repulsion between the charged double layers prevents the particles from colliding, stabilizing the colloids. These solids are often undesirable because they can contain toxins that are difficult to remove. Coagulation is a technique that helps aggregate and...
357
Colloidal precipitates01:09

Colloidal precipitates

725
The high insolubility of some precipitates can result in an unfavorable relative supersaturation. This can lead to colloidal particles with a large surface-to-mass ratio, where adsorption is promoted. For instance, in the precipitation of silver chloride, silver ions are adsorbed on the surface of the colloidal particles, forming a primary layer. This layer attracts ions of opposite charge (such as nitrate ions), forming a diffuse secondary layer of adsorbed ions. This electric double layer...
725
Colloids03:22

Colloids

17.8K
Children at play often make suspensions such as mixtures of mud and water, flour and water, or a suspension of solid pigments in water known as tempera paint. These suspensions are heterogeneous mixtures composed of relatively large particles that are visible to the naked eye or can be seen with a magnifying glass. They are cloudy, and the suspended particles settle out after mixing. On the other hand, a solution is a homogeneous mixture in which no settling occurs and in which the dissolved...
17.8K
Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)01:20

Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)

1.1K
Two NMR-active nuclei bonded to a central atom can be involved in geminal or two-bond coupling. Geminal coupling is commonly seen between diastereotopic protons in chiral molecules and unsymmetrical alkenes, among others.
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...
1.1K
Colloids and Suspensions01:17

Colloids and Suspensions

2.1K
Children at play often make suspensions such as mixtures of mud and water, flour and water, or a suspension of solid pigments in water known as tempera paint. These suspensions are heterogeneous mixtures composed of relatively large particles visible to the naked eye or seen with a magnifying glass. They are cloudy, and the suspended particles settle out after mixing. The suspended particles in a suspension settle out after some time of mixing. The separation of particles from a suspension is...
2.1K
Spin–Spin Coupling: Three-Bond Coupling (Vicinal Coupling)01:22

Spin–Spin Coupling: Three-Bond Coupling (Vicinal Coupling)

1.1K
Vicinal or three-bond coupling is commonly observed between protons attached to adjacent carbons. Here, nuclear spin information is primarily transferred via electron spin interactions between adjacent C‑H bond orbitals. This generally favors the antiparallel arrangement of spins, so 3J values are usually positive.
The extent of coupling depends on the C‑C bond length, the two H‑C‑C angles, any electron-withdrawing substituents, and the dihedral angle between the...
1.1K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Charge localization, rectification, and transport in electrolyte patchy nanochannels.

Faraday discussions·2026
Same author

Plug flow down to the nanoscale can induce partial solidification of confined fluids.

Soft matter·2026
Same author

Periodic confined cell migration drives partially reversible chromatin reorganization in cancer cell lines.

Communications biology·2026
Same author

Theory of active self-organization of dense nematic structures in the actin cytoskeleton.

eLife·2025
Same author

Unravel the rotational and translational behavior of a single squirmer in flexible polymer solutions at different Reynolds numbers.

Communications physics·2025
Same author

Sorting of binary active-passive mixtures in designed microchannels.

Soft matter·2025

Related Experiment Video

Updated: Aug 30, 2025

Reliable Mechanochemistry: Protocols for Reproducible Outcomes of Neat and Liquid Assisted Ball-mill Grinding Experiments
13:05

Reliable Mechanochemistry: Protocols for Reproducible Outcomes of Neat and Liquid Assisted Ball-mill Grinding Experiments

Published on: January 23, 2018

10.7K

Onsager reciprocal relations and chemo-mechanical coupling for chemically active colloids.

Marco De Corato1, Ignacio Pagonabarraga2

  • 1Aragon Institute of Engineering Research (I3A), University of Zaragoza, Zaragoza, Spain.

The Journal of Chemical Physics
|September 1, 2022
PubMed
Summary

Chemically active colloids use environmental energy for self-propulsion via surface reactions. This study validates Onsager reciprocal relations for active colloids, revealing their breakdown near nonequilibrium states.

More Related Videos

Synthesis and Characterization of Supramolecular Colloids
09:26

Synthesis and Characterization of Supramolecular Colloids

Published on: April 22, 2016

9.9K
Quantitative and Qualitative Examination of Particle-particle Interactions Using Colloidal Probe Nanoscopy
13:15

Quantitative and Qualitative Examination of Particle-particle Interactions Using Colloidal Probe Nanoscopy

Published on: July 18, 2014

11.1K

Related Experiment Videos

Last Updated: Aug 30, 2025

Reliable Mechanochemistry: Protocols for Reproducible Outcomes of Neat and Liquid Assisted Ball-mill Grinding Experiments
13:05

Reliable Mechanochemistry: Protocols for Reproducible Outcomes of Neat and Liquid Assisted Ball-mill Grinding Experiments

Published on: January 23, 2018

10.7K
Synthesis and Characterization of Supramolecular Colloids
09:26

Synthesis and Characterization of Supramolecular Colloids

Published on: April 22, 2016

9.9K
Quantitative and Qualitative Examination of Particle-particle Interactions Using Colloidal Probe Nanoscopy
13:15

Quantitative and Qualitative Examination of Particle-particle Interactions Using Colloidal Probe Nanoscopy

Published on: July 18, 2014

11.1K

Area of Science:

  • Colloid Science
  • Chemical Physics
  • Soft Matter Physics

Background:

  • Synthetic colloids, like microorganisms, can self-propel using environmental energy via surface reactions.
  • Chemo-mechanical coupling governs this self-propulsion, linking chemical reactions to motion.
  • Onsager reciprocal relations describe the interplay between chemical and mechanical driving forces.

Purpose of the Study:

  • To investigate chemo-mechanical coupling and Onsager reciprocal relations in self-propelling active colloids.
  • To analyze the behavior of a spherical active colloid catalyzing a reversible surface reaction.
  • To determine the validity and limitations of Onsager relations in different thermodynamic states.

Main Methods:

  • Solving transport equations using perturbation expansion.
  • Employing numerical simulations to validate theoretical predictions.
  • Analyzing a spherical colloid with a reversible surface catalytic reaction.

Main Results:

  • Demonstrated the validity of Onsager reciprocal relations near equilibrium for active colloids.
  • Identified solute advection as crucial for maintaining the symmetry of the Onsager matrix.
  • Showed that Onsager reciprocal relations break down in nonequilibrium steady states.

Conclusions:

  • Onsager reciprocal relations are valid near equilibrium, governing the coupling between chemical reactions and motion in active colloids.
  • Solute advection plays a key role in preserving the symmetry of these relations.
  • The breakdown of Onsager relations near nonequilibrium states has significant implications for understanding active colloid behavior and thermal fluctuations in experimental settings.