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

Network Covalent Solids02:18

Network Covalent Solids

14.9K
Network covalent solids contain a three-dimensional network of covalently bonded atoms as found in the crystal structures of nonmetals like diamond, graphite, silicon, and some covalent compounds, such as silicon dioxide (sand) and silicon carbide (carborundum, the abrasive on sandpaper). Many minerals have networks of covalent bonds.
To break or to melt a covalent network solid, covalent bonds must be broken. Because covalent bonds are relatively strong, covalent network solids are typically...
14.9K
Porosity and Absorption of Aggregate01:20

Porosity and Absorption of Aggregate

439
Aggregates contain pores of varying sizes; while some are completely enclosed within the particles, others open onto the surface, allowing water to penetrate. The porosity of aggregates is a major factor contributing to the overall porosity of concrete, given that aggregates constitute about three-quarters of concrete's volume.
When all pores in an aggregate are filled with water, the aggregate is considered saturated and surface-dry. If left in dry air, water will evaporate until the...
439
Structure of Porins01:21

Structure of Porins

3.3K
Mitochondria, chloroplasts, and gram-negative bacteria have transmembrane, beta-barrel proteins called porins to mediate the free diffusion of ions and metabolites across the membrane. Mitochondrial porin precursors contain conserved amino acid sequences called beta signals at their C-terminal. Beta signals have a  motif of PoXGXXHyXHy (Po-Polar, X-Any amino acid, G-Glycine, Hy-LargeHydrophobic), which are crucial for precursor recognition to initiate precursor assembly. Beta-barrel...
3.3K
Crystal Field Theory - Octahedral Complexes02:58

Crystal Field Theory - Octahedral Complexes

28.2K
Crystal Field Theory
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
28.2K
Pore Size Distribution01:23

Pore Size Distribution

228
In concrete, the pore size distribution significantly influences the material's properties. Capillary pores, markedly larger than gel pores, form a vast network within partially hydrated cement paste, reducing the concrete's strength and increasing its permeability. This heightened permeability leads to a greater risk of damage from environmental factors like freeze-thaw cycles and chemical attacks, with the extent of vulnerability also being tied to the water-to-cement ratio.
Adequate...
228
Aromatic Hydrocarbon Anions: Structural Overview01:18

Aromatic Hydrocarbon Anions: Structural Overview

3.1K
Neutral hydrocarbons like cyclopentadiene with an odd number of carbon atoms and one intervening CH2 group in the ring are not aromatic. Cyclopentadiene with 4 π electrons does not satisfy the 4n + 2 π electron rule. Additionally, the intervening CH2 group is sp3 hybridized and lacks a vacant p orbital, thereby interrupting the overlap of p orbitals in a continuous manner and preventing the delocalization of π electrons throughout the ring.
Due to the absence of continuous...
3.1K

You might also read

Related Articles

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

Sort by
Same author

Growth-Coupled Assembly of Hydrogen-Bonded Organic Framework Membranes on Cell Surfaces.

Journal of the American Chemical Society·2026
Same author

Single-port compared with conventional laparoscopic ovarian cystectomy for benign ovarian cysts: a systematic review and meta-analysis.

Frontiers in oncology·2026
Same author

Antibiotic residues in cattle manure increase greenhouse gas emissions during solid storage in Kenya.

Journal of environmental management·2026
Same author

Anode-pressurized water electrolysis with modulated anion exchange membrane architecture.

Nature communications·2026
Same author

Water-Induced Dynamic Structural Adaptivity of Zr-MOF for Holistic Metrics Optimization in Atmospheric Water Harvesting.

Journal of the American Chemical Society·2026
Same author

Two-dimensional p-π conjugated amide-linked polymeric photocatalysts with enhanced carrier separation.

Nature communications·2026
Same journal

Decoding Galectin-Glycan Recognition with <sup>19</sup>F-Tagged Lectins: from Simple Glycans to the Cellular Glycocalyx.

Journal of the American Chemical Society·2026
Same journal

Open- and Closed-Shell Roles of Sensitizer and Annihilator in Pseudo-Single Component Mixtures for Upconversion.

Journal of the American Chemical Society·2026
Same journal

Pressure-Induced Superconductivity at 15 K in van-der-Waals Ferroelectric CuInP<sub>2</sub>S<sub>6</sub>.

Journal of the American Chemical Society·2026
Same journal

Carbene Analogues of Group 15: Reduction of s-Hydrindacene-Based Chloropnictogenium Ions To Access an Antimony Hydride Monocation and a Trinuclear Bismuth Dication.

Journal of the American Chemical Society·2026
Same journal

Chiral-Ligand-Modulated Nickel-Catalyzed Stereoselective Radical Migratory C2-Arylation of Carbohydrates.

Journal of the American Chemical Society·2026
Same journal

Coordination-Constraint-Driven Enhanced Chirality Induction in Perovskite Quantum Dot Solids.

Journal of the American Chemical Society·2026
See all related articles

Related Experiment Video

Updated: Oct 1, 2025

Microfluidic-based Synthesis of Covalent Organic Frameworks COFs: A Tool for Continuous Production of COF Fibers and Direct Printing on a Surface
08:42

Microfluidic-based Synthesis of Covalent Organic Frameworks COFs: A Tool for Continuous Production of COF Fibers and Direct Printing on a Surface

Published on: July 10, 2017

13.6K

Covalent Organic Frameworks with Record Pore Apertures.

Zhenjie Mu1, Yuhao Zhu1, Bixiao Li1

  • 1Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, Key Laboratory of Cluster Science, Ministry of Education, Advanced Technology Research Institute (Jinan), Frontiers Science Center for High Energy Material, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, P. R. China.

Journal of the American Chemical Society
|March 8, 2022
PubMed
Summary
This summary is machine-generated.

Researchers developed new covalent organic frameworks (COFs) with record-large, uniform mesopores up to 10.0 nm. These stable, crystalline materials enable the separation of large biomolecules like pepsin and protect enzymes.

More Related Videos

Synthesis and Characterization of Functionalized Metal-organic Frameworks
11:27

Synthesis and Characterization of Functionalized Metal-organic Frameworks

Published on: September 5, 2014

48.4K
Author Spotlight: Characterizing Porous Materials for Aiding the Development of Robust Metal-Organic Frameworks with Adsorption Behavior
06:45

Author Spotlight: Characterizing Porous Materials for Aiding the Development of Robust Metal-Organic Frameworks with Adsorption Behavior

Published on: March 8, 2024

8.3K

Related Experiment Videos

Last Updated: Oct 1, 2025

Microfluidic-based Synthesis of Covalent Organic Frameworks COFs: A Tool for Continuous Production of COF Fibers and Direct Printing on a Surface
08:42

Microfluidic-based Synthesis of Covalent Organic Frameworks COFs: A Tool for Continuous Production of COF Fibers and Direct Printing on a Surface

Published on: July 10, 2017

13.6K
Synthesis and Characterization of Functionalized Metal-organic Frameworks
11:27

Synthesis and Characterization of Functionalized Metal-organic Frameworks

Published on: September 5, 2014

48.4K
Author Spotlight: Characterizing Porous Materials for Aiding the Development of Robust Metal-Organic Frameworks with Adsorption Behavior
06:45

Author Spotlight: Characterizing Porous Materials for Aiding the Development of Robust Metal-Organic Frameworks with Adsorption Behavior

Published on: March 8, 2024

8.3K

Area of Science:

  • Materials Science
  • Polymer Chemistry
  • Nanotechnology

Background:

  • Porous materials with tunable pore sizes are crucial for molecular separation and protection.
  • Existing metal-organic frameworks (MOFs) and covalent organic frameworks (COFs) have limitations in pore aperture size, hindering access for large molecules.
  • Achieving uniform, large mesopores in crystalline porous polymers remains a significant challenge.

Purpose of the Study:

  • To construct novel covalent organic frameworks (COFs) with record-breaking, predesigned mesopore apertures.
  • To overcome the limitations of interpenetration and structural fragility in creating large-pore COFs.
  • To demonstrate the utility of these novel COFs in practical applications involving large biomolecules.

Main Methods:

  • Design and synthesis of novel building blocks with enhanced conformational rigidity, planarity, and controlled local polarity.
  • Characterization of the resulting covalent organic frameworks (COFs) for crystallinity, porosity, stability, and pore size distribution.
  • Application of the synthesized COFs in biomolecule separation and enzyme protection.

Main Results:

  • A series of covalent organic frameworks (COFs) were successfully synthesized with pore aperture values ranging from 7.7 to 10.0 nm, surpassing previous records.
  • The obtained COFs exhibited high crystallinity, permanent porosity, structural stability, and eclipsed stacking.
  • Demonstrated successful separation of pepsin (approximately 7 nm) from crude mixtures and protection of tyrosinase from heat-induced denaturation.

Conclusions:

  • The developed strategy enables the construction of covalent organic frameworks (COFs) with unprecedentedly large and uniform mesopores.
  • These novel COFs offer significant potential for advanced separation technologies and biomolecular stabilization.
  • The findings pave the way for designing next-generation porous materials for complex molecular interactions.