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The fraction of a specified population of chemical atoms that has become ionized. For singly ionized atoms with no external charge source, charge neutrality gives equal free-electron and ion number densities. Its equilibrium value depends on both temperature and total number density through the Saha ionization equation.
A geometric heuristic favouring the largest coordination number compatible with neighbouring opposite-charge ions touching the central ion without overlap. A limiting radius ratio rule comes from additionally making the surrounding ions just touch. It is a hard-sphere model, not an exact stability criterion.
A hard-sphere model relating the radius ratio of opposite-charge ions to a possible coordination number. For a cube of eight mutually touching anions around a touching cation, ; real bonding and coordination-dependent radii limit its predictive power.
Evolutionary reassortment of exon-associated coding segments. Introns can provide boundaries permitting changes in protein-domain arrangement, but the role of a particular intron requires historical evidence.
An introduced species whose establishment and spread cause adverse effects under the specified ecological definition. Presence outside the native range does not alone establish an impact.
The chemical potential fixed by equal conduction-electron and valence-hole densities in an intrinsic semiconductor. In the nondegenerate parabolic-band model, .
In a symmetric model with constant density of states per volume and energy in two broad bands, charge neutrality gives and . In the nondegenerate limit, . Thus the leading exponential activation law can coexist with an algebraic temperature prefactor.
The SI unit of absorbed dose.[ref]
The International System of Units (SI), ninth edition, SI Brochure. Appendix 1, 15th CGPM (1975), Resolution 9, special name gray
The SI unit used for equivalent dose and effective dose. Sharing dimensions with the gray does not make the quantities interchangeable.[ref]
The International System of Units (SI), ninth edition, SI Brochure. Appendix 1, 16th CGPM (1979), Resolution 5; CIPM Recommendation 1 (1984)
Work by International Association for the Properties of Water and Steam by 
Codex 0 Created 2026-10-20 Updated 2026-10-31
Codex 0 Created 2026-10-20 Updated 2026-10-31With friction , inward force gives constant entry speed after capture. With the field off, constant outward entropic force gives and a quadratic recoil time. Exterior drag, adsorption and the short final end region are omitted. These ideal transport times alone do not establish steady size separation through a whole uniform channel.
Display of antigen-derived material for immune recognition, including peptide display by MHC molecules to T-cell receptors. Processing, expression and recognition are distinct requirements.
Pinned article: Introduction to the OurBigBook Project
Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
Intro to OurBigBook
. Source. We have two killer features:
- topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculusArticles of different users are sorted by upvote within each article page. This feature is a bit like:
- a Wikipedia where each user can have their own version of each article
- a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.
Figure 1. Screenshot of the "Derivative" topic page. View it live at: ourbigbook.com/go/topic/derivativeVideo 2. OurBigBook Web topics demo. Source. - local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
- to OurBigBook.com to get awesome multi-user features like topics and likes
- as HTML files to a static website, which you can host yourself for free on many external providers like GitHub Pages, and remain in full control
Figure 2. You can publish local OurBigBook lightweight markup files to either OurBigBook.com or as a static website.
Figure 3. Visual Studio Code extension installation.
Figure 5. . You can also edit articles on the Web editor without installing anything locally. Video 3. Edit locally and publish demo. Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension. 
- Infinitely deep tables of contents:
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact