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Provider-curated glucosylceramide class: glucose monosaccharide headgroup and variable lipid substituents. Related subclass www.ebi.ac.uk/chebi/CHEBI:18368 specifies D-glucosyl-N-acylsphingosine; do not substitute its one-variable-group formula for the broader class.
Provider-curated general xanthine record: purine nucleobase, formula C5H4N4O2, neutral charge. www.ebi.ac.uk/chebi/CHEBI:17712 is specifically9H-xanthine, with oxo groups at2 and6 and N9 protonation; not the general tautomer-unspecified record.
Provider-curated general urate anion definition and conjugate-base relationship. Monoanion www.ebi.ac.uk/chebi/CHEBI:30848 : formula C5H3N4O3, net charge-1. The generic record also includes dianions; it is not exclusively the monoanion.
Nomenclature of Lipids by the IUPAC-IUB Commission on Biochemical Nomenclature by 
Codex 0 2026-11-05
Codex 0 2026-11-05 Sedimentation, creaming, centrifugation and diffusion in the IUPAC colloid terminology by Codex 0 2026-11-05
Codex 0 2026-11-05Official IUPAC terminology table: sedimentation coefficient and Svedberg unit S=10^-13 second. Parallel definition and unit discussion media.iupac.org/reports/2001/colloid_2001/manual_of_s_and_t/node40.html .
1994, Determination of Trace Elements in Waters and Wastes by Inductively Coupled Plasma-Mass Spectrometry. Section3.2 defines calibration standards as dilutions of stock standard solutions used to relate instrument response to analyte concentration; §7.4 gives calibration-standard preparation. Official original method, not a claim about current regulatory approval.
EntryS05746, DOI10.1351/goldbook.S05746, online version5.0.0(2025). Verified indexed official entry: liquid or solid phase containing more than one substance, solvent/solute designation. Terminology authority, not new experimental data. Direct fetch returned403; official indexed text and PDF goldbook.iupac.org/terms/view/S05746/pdf verified the definition.
Primary publisher-preview text inspected via indexed excerpt, Chapter1 printed page4, §§1.13–1.15: blank indication, blank material and blank value. Section1.15 defines conversion of a blank indication by a calibration function. No edition date or individual editor/author inferred from the excerpt; IUPAC is the issuing organization.
Direct primary CHEBI:30854 record: Definition, Formula, Net Charge and conjugate-base relation to CHEBI:16411. Formula C10H8NO2, charge-1. Article uses a symbolic pH-minus-pKa calculation, not a newly claimed measured pKa.
Directly inspected definition and Standard Source panel. Analytical control for contamination/interference from labware, reagents and solvents; identifies ANSI/ASTM E1732(2025) as standard source. No claim that NIST originally authored the ASTM definition.
Originating manufacturer technical information. Product Range identifies polyethersulfone(PESU), polysulfone(PSU) and polyphenylsulfone(PPSU) as distinct amorphous thermoplastic families. Original product brochure www.basf.com/dam/jcr%3Acb9e928f-9c26-3ceb-9a08-f7cc23f160bf/basf/www/cn/documents/en/chinaplas/UltrasonESPproductbrochureEN.pdf , printed p.10, identifies the families and corresponding repeat-structure diagrams; full PDF retrieval exceeded the browser size limit, so no visual inspection is claimed. No universal grade-independent service limit inferred.
Originating curated chemical record. Definition: ether with oxygen joined to two methyl groups; structure and formula C2H6O; synonym methoxymethane. NIST record CAS115-10-6 independently identifies the same compound.
Nomenclature in evaluation of analytical methods including detection and quantification capabilities by Lloyd A. Currie by Codex 0 2026-11-05
Codex 0 2026-11-05IUPAC Recommendations1995, Pure and Applied Chemistry67(10),1699–1723; DOI10.1351/pac199567101699. Prepared for publication by Lloyd A. Currie. Primary indexed title/byline and page1709 text inspected, §§3.7.2–3.7.3: measurement-process scope, type-I/type-II errors and distinction of critical decision value from detection capability. Direct PDF retrieval returned403; no full-PDF or figure-image inspection claimed.
DOI10.1351/goldbook.08008. Official primary indexed entry: correction removes effect of blank indication; quantities must be of the same kind; subtraction or transmittance division depending on measurement model. Underlying2021 IUPAC recommendations, page1001.
DOI10.1351/goldbook.08010. Official indexed definition and notes3–6 verified: material contains no or as little as possible analyte; distinguish blank material, indication, correction and procedural scope. Underlying Metrological and quality concepts in analytical chemistry(IUPAC Recommendations2021), PAC93,997, term on page1001. Direct HTML retrieval challenged; no full-paper inspection claimed.
Originating curated generic homocysteine entry: Definition, Structure and Ontology show the sulfur-containing non-proteinogenic amino acid, neutral formula C4H9NO2S and unspecified stereochemistry. Specific L form www.ebi.ac.uk/chebi/CHEBI:17588 has (2S) configuration. Keep generic and stereospecific identities distinct.
CHEBI:16680. Verified Definition, Formula, Net Charge and structure: S-adenosyl derivative of L-homocysteine, neutral representation C14H20N6O5S. Other protonation representations are distinct entries; no concentration-based clinical interpretation inferred.
DOI10.1351/goldbook.L03540. Official indexed definition verified: concentration or quantity derived from the smallest measure detected with reasonable certainty for a specified procedure; blank mean plus a confidence-dependent multiple of blank standard deviation. Direct historical HTML/PDF retrieval failed, so no full-PDF inspection claimed. The article's equal-variance normal example is an explicitly derived model, not a universal prescribed multiplier.
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