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

Positron Emission Tomography01:29

Positron Emission Tomography

6.2K
Positron emission tomography (PET) is a medical imaging technique involving radiopharmaceuticals — substances that emit short-lived radiation. Although the first PET scanner was introduced in 1961, it took 15 more years before radiopharmaceuticals were combined with the technique and revolutionized its potential.
One of the main requirements of a PET scan is a positron-emitting radioisotope, which is produced in a cyclotron and then attached to a substance used by the part of the body...
6.2K
Imperfections in Crystal Structure: Stoichiometric Point Defects01:26

Imperfections in Crystal Structure: Stoichiometric Point Defects

143
Schottky defects arise when some lattice points in a crystal, such as those in NaCl, remain unoccupied, creating lattice vacancies without disturbing the overall electrical neutrality of the crystal. This defect is common in ionic crystals where the positive and negative ions are similar in size, as seen in sodium chloride and cesium chloride. The presence of Schottky defects enables the crystal to conduct electricity to a small extent through an ionic mechanism. Electric fields cause nearby...
143
Imperfections in Crystal Structure: Non-Stoichiometric Defects01:29

Imperfections in Crystal Structure: Non-Stoichiometric Defects

115
Non-stoichiometric defects refer to a type of defect in the crystal structure of a compound where the ratio of its constituent elements deviates from the ideal stoichiometric ratio. There are two main types of non-stoichiometric defects: metal excess defects and metal deficiency defects.Metal excess defects occur when there is a slight surplus of metal ions than what is required by the stoichiometric ratio of the compound. For example, heating a sodium chloride crystal in sodium vapor results...
115
Imperfections in Crystal Structure: Point, Line and Plane Defects01:25

Imperfections in Crystal Structure: Point, Line and Plane Defects

150
A perfect crystal, in theory, has a uniform structure with the same unit cell and lattice points throughout. However, any deviation from this periodic arrangement is known as an imperfection or defect. These defects can be categorized into three types: point, line, and plane defects.Point defects occur when there is a deviation from the ideal due to missing atoms, displaced atoms, or additional atoms. These imperfections might occur due to imperfect packing during crystallization or because of...
150

You might also read

Related Articles

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

Sort by
Same author

Bone transcriptomics reveals that juzentaihoto remodels and activates multiple pathways in Klotho-deficient mice.

Bone reports·2026
Same author

Intron Retention as a Homeostatic State Variable for Drug Response and Recovery: Lessons from Depression for Broader Applications.

International journal of molecular sciences·2026
Same author

Activation of human and mouse transient receptor potential vanilloid 1 by enantiomeric evodiamine and rutaecarpine.

Journal of natural medicines·2026
Same author

The IR-Homeostat Hypothesis: Intron Retention as an Evolutionarily Conserved Fine-Tuning Layer and a Reversible Blood Biomarker of Homeostatic Dysregulation in Mood Disorders.

International journal of molecular sciences·2026
Same author

Bioinspired silver nanoparticles from <i>Artemisia lerchiana</i> as durable electrodes for next-generation supercapacitors.

Physical chemistry chemical physics : PCCP·2026
Same author

Sustainable wastewater treatment by banana peel/layered double hydroxide composite under ideal conditions using the Taguchi method.

Scientific reports·2026

Related Experiment Video

Updated: May 3, 2026

Half-segmental Diaphyseal Bone Defect Model in Rats for Evaluating Bone Substitute Performance in Load-bearing Regions
04:32

Half-segmental Diaphyseal Bone Defect Model in Rats for Evaluating Bone Substitute Performance in Load-bearing Regions

Published on: December 30, 2025

312

Structural defects and positronium formation in 40 keV B(+)-implanted polymethylmethacrylate.

Taras Kavetskyy1, Volodymyr Tsmots, Atsushi Kinomura

  • 1Faculty of Biology and Solid-State Microelectronics Laboratory, Drohobych Ivan Franko State Pedagogical University , 24 I. Franko Str., Drohobych 82100, Ukraine.

The Journal of Physical Chemistry. B
|January 29, 2014
PubMed
Summary

This study investigates structural defects and positronium formation in boron-implanted polymethylmethacrylate (B:PMMA) using positron annihilation. Results reveal distinct defect formation processes, including free radical appearance and carbonization, dependent on ion dose.

More Related Videos

Effects of Mechanical Methods Used in Peri-implantitis Treatment on Implant Surface Decontamination and Roughness
06:36

Effects of Mechanical Methods Used in Peri-implantitis Treatment on Implant Surface Decontamination and Roughness

Published on: March 14, 2025

1.1K
Multi-Scale Modification of Metallic Implants With Pore Gradients, Polyelectrolytes and Their Indirect Monitoring In vivo
12:19

Multi-Scale Modification of Metallic Implants With Pore Gradients, Polyelectrolytes and Their Indirect Monitoring In vivo

Published on: July 1, 2013

10.3K

Related Experiment Videos

Last Updated: May 3, 2026

Half-segmental Diaphyseal Bone Defect Model in Rats for Evaluating Bone Substitute Performance in Load-bearing Regions
04:32

Half-segmental Diaphyseal Bone Defect Model in Rats for Evaluating Bone Substitute Performance in Load-bearing Regions

Published on: December 30, 2025

312
Effects of Mechanical Methods Used in Peri-implantitis Treatment on Implant Surface Decontamination and Roughness
06:36

Effects of Mechanical Methods Used in Peri-implantitis Treatment on Implant Surface Decontamination and Roughness

Published on: March 14, 2025

1.1K
Multi-Scale Modification of Metallic Implants With Pore Gradients, Polyelectrolytes and Their Indirect Monitoring In vivo
12:19

Multi-Scale Modification of Metallic Implants With Pore Gradients, Polyelectrolytes and Their Indirect Monitoring In vivo

Published on: July 1, 2013

10.3K

Area of Science:

  • Materials Science
  • Polymer Physics
  • Radiation Damage

Background:

  • Polymethylmethacrylate (PMMA) is susceptible to structural changes under ion implantation.
  • Understanding defect formation is crucial for tailoring material properties.

Purpose of the Study:

  • To investigate structural defects and positronium formation in B(+)-implanted PMMA.
  • To elucidate the mechanisms of defect evolution with varying ion doses.

Main Methods:

  • Slow positron beam implantation spectroscopy.
  • Doppler broadening of positron annihilation gamma rays.
  • Optical absorption measurements.
  • Comparison with SRIM simulations.

Main Results:

  • Identified two primary defect formation processes: free radical appearance at lower doses and carbonization at higher doses.
  • Observed dose-dependent changes in positron annihilation parameters (S-parameter, o-Ps lifetime and intensity).
  • Optical absorption increased with ion dose, indicating carbonaceous phase formation.

Conclusions:

  • Boron implantation induces significant structural modifications in PMMA.
  • Positron annihilation spectroscopy effectively probes radiation-induced defects and polymer chain scission.
  • The findings provide insights into polymer modification via ion implantation for potential applications.