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Reference Materials for Phase Equilibrium Studies. 1. Liquid-Liquid Equilibria by Ala Bazyleva and others by
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IUPAC Technical Report, Pure and Applied Chemistry 93(7), 2021; DOI10.1515/pac-2020-0905. Title-page byline gives Ala Bazyleva as corresponding author and task-group chair. Abstract and Introduction: seven reference binary systems, critically evaluated property values and estimated uncertainties for validating phase-equilibrium instruments and techniques.
Corporate primary technical information, Elastic element pressure gauges, WIKA data sheet IN00.01, September2010. Precise locators: p1, Description, atmospheric reference; p1, Pressure gauges with bourdon tube and labelled tube/linkage/pointer mechanism; p3, Absolute pressure gauges, sealed reference arrangement. No individual author is inferred. The numerical motion coefficients in the article are original teaching inputs, not product specifications. New WIKA and Work by WIKA headers are EMPTY in owned metrology.bigb.
Vibroscope method for determination of cross-sectional area of glass and carbon fibres - Theory and further development by Bo Madsen and others by
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Composites Part A 187, 108446 (2024); DOI10.1016/j.compositesa.2024.108446. By Bo Madsen, Jan Høgsberg and Hans Lilholt. §2.1, tensioned Euler-Bernoulli beam; §2.2, fully clamped boundary conditions and frequency equation; §§5–6, deformation corrections. The simple hinged-beam example in the estimator article is derived separately.
Weighing by Double Substitution by National Institute of Standards and Technology by
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Recommended Standard Operating Procedure for Weighing by Double Substitution, SOP4,2019, part of NISTIR6969–2019. Corporate primary publication; no individual authorship inferred. Precise locators: p1, Purpose, comparison twice with a known standard and response calibration using a sensitivity mass; pp6–8, actual sequences/observation instructions; §3 and uncertainty section, buoyancy and density contributions. The article's separate equally spaced four-reading cancellation example is an original simplified model, not a transcription of this full procedure.
Certificate for Standard Reference Material 1922 by National Institute of Standards and Technology by
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Archived certificate, issue date24June2009, Standard Reference Material1922, Liquid Refractive Index - Mineral Oil. Page1 describes a precision spectrometer-goniometer, minimum-deviation measurements, an oil-filled hollow prism, water-bath temperature control and tests on multiple aliquots. Page2, Table1 gives wavelength-specific values at20degrees Celsius, temperature coefficients and expanded uncertainties with coverage factor2;589.3nm value comes from fitted dispersion data. Used as a historical physical reference-material example, without a current-availability or current-certificate claim.
Additional locators in the archived 2009 certificate: p. 1, multiple-aliquot homogeneity tests and conditional certification validity; p. 3, original bottle, tight recapping, ambient storage and protection against excessive moisture and light.
Vibroscope method for determination of cross-sectional area of glass and carbon fibres – Experiments and analyses by Bo Madsen and others by
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Composites Part A: Applied Science and Manufacturing187,108447(2024). Explicit primary byline Bo Madsen, Rajnish Kumar and Hans Lilholt; first author marked corresponding author. Public abstract: frequency measurements of a tensioned fibre, simple/direct/iterative area analysis, area distributions and stress-strain comparisons. Full-text apparatus locators are given below.
Full text: backend.orbit.dtu.dk/ws/portalfiles/portal/375268265/1-s2.0-S1359835X24004445-main.pdf . §3.2 documents the Favimat+ apparatus, acoustic excitation, resonance fitting and readout resolutions; §§2.1–2.2 distinguish the simple estimate from correction procedures.
How to Consistently Verify the Performance of Nanopositioning Motion Control Equipment by Physik Instrumente by
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Part2 of Metrology for Precision Motion / Positioning Systems - Methods and Principles. §§3.1–3.2: repeated approaches, static readout, interferometer/autocollimator and paired reflectors; §§4.1–4.4: direction-specific means, scatter, reversal and repeatability. Manufacturer's stated method, including its declared adaptations of the cited positioning-test standards.
Additional locators: §4.3, axis-wide maximum of absolute directional mean differences; §4.4, unidirectional and bidirectional aggregation conventions.
NBS Handbook H28(1944), Section II, Terminology, 1(a), definition1: a uniform-section ridge following a cylindrical helix or a conical spiral, on an external or internal surface. Used for historical geometric terminology only, not present-day dimensional compliance or current standards. No individual author identity inferred from the committee roster.
Precision Motion and Positioning: Difference between Micropositioning and Nanopositioning by Physik Instrumente by
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Manufacturer tutorial, Glossary: Design Resolution is theoretical from screw/gearing/motor increments; Minimum Incremental Motion is repeatedly executable movement. Backlash, elastic drivetrain effects and friction distinguish commanded and load motion. Used for terminology and physical mechanism only; original chosen drive and repeated-move data are not product measurements or recommendations.
Water Calorimetry: A Correction to the Heat Defect Calculations by Norman V. Klassen and Carl K. Ross by
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Journal of Research of NIST107(2),171–178(2002); DOI10.6028/jres.107.015. First-page bylines Norman V. Klassen and Carl K. Ross, with Ionizing Radiation Standards, National Research Council, Ottawa affiliation, verified directly. Printed p.171, Abstract and Introduction: correction of an erroneous literature reaction-rate constant in the earlier model III and introduction of model IIIR; independent calorimetric and chemical-product comparisons. No historical gas-system numerical recommendation is adopted here.
Applied Radiation and Isotopes68(7–8),1561–1565(2010), DOI10.1016/j.apradiso.2009.11.052. Primary abstract verifies byline Eduardo García-Toraño, Virginia Peyrés Medina and Miguel Roteta Ibarra; three detector systems, measurements up to nine half-lives and reported1.82871(18)h. This is the result of that experiment, not a claim about the latest evaluated value.
OIML R76-1, Edition2006(E), Non-automatic weighing instruments; Part1: Metrological and technical requirements - Tests. T.1.1 (printed p5) defines weighing as mass determination using gravity. T.5.2.1–T.5.2.3 and T.5.3.1–T.5.3.2 (printed p16; PDF index15) define gross, net, tare and preset-tare/calculated-net values, with the zero-indication condition. Used for measurement terminology, not current jurisdictional compliance guidance.
Rigorous evaluation of chemical measurement uncertainty: Liquid chromatographic analysis methods using detector response factor calibration by Blaza Toman and others by
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Primary Metrologia54(3),S16 article. Verified first-author byline Blaza Toman. Only the general physical measurement model from the introduction is used: equations1–3 define RF as amount-per-response, and the discussion after equation3/equation4 establishes correlations from a shared calibration factor. The body uses a different, explicitly defined signal-per-amount convention and original numerical data; no biological samples or protocols are described.
Journal of Research of NIST102(1),63–74(1997); DOI10.6028/jres.102.006. First-page full bylines verified. Printed p.63, Eqs1–2 define D_w=c_w ΔT/(1-k_HD) and k_HD=(E_a-E_h)/E_a; Abstract and Introduction compare radiolysis calculations with hydrogen-peroxide measurements. Later numerical-model correction: doi.org/10.6028/jres.107.015 (2002); no historical gas-system numerical recommendation used here.
An Absorbed Dose Water Calorimeter: Theory, Design, and Performance by Steve R. Domen by
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Journal of Research of the National Bureau of Standards87(3),211–235(1982); DOI10.6028/jres.087.016. Verified full byline Steve R.Domen. Abstract and opening description: two calibrated thermistors in a water medium, local temperature-rise measurement and conversion through water specific heat capacity. Public-domain NBS paper.
Directly inspected VIM3 entry4.2, blank indication: indication from a similar phenomenon/body/substance with the quantity of interest assumed absent or not contributing. Cite the specific edition/entry; do not conflate the broader VIM background-indication alternate term with every narrower chemical blank usage.
Further VIM3 locators: Entry 5.1, measurement standard, definition and notes 1–5 and Entry 2.8, primary reference measurement procedure, definition and gravimetric-volume example.
Further VIM3 locators: Entry2.15, measurement precision; Entry2.20, repeatability conditions; Entry2.21, measurement repeatability.
Further VIM3 entries: 2.14, measurement trueness; 2.22, intermediate precision conditions; 2.23, intermediate measurement precision; 2.24, reproducibility conditions; 2.25, measurement reproducibility.
Further VIM3 entries: 2.6, measurement procedure and 3.2, measuring system.
Verified device and procedure entries: jcgm.bipm.org/vim/en/3.1.html and jcgm.bipm.org/vim/en/3.2.html and jcgm.bipm.org/vim/en/2.6.html
Entry3.1 is measuring instrument; entry3.2 is measuring system, which may consist of one instrument. Entry2.6 defines a detailed measurement procedure including a model and calculation, with an optional target uncertainty.
Additional verified VIM3 material entries: jcgm.bipm.org/vim/en/5.13.html and jcgm.bipm.org/vim/en/5.14.html
Entry5.13 defines reference material through property-specific homogeneity, stability and fitness for intended use; note2 distinguishes precision control without an assigned value from calibration/trueness control requiring an assigned value. Entry5.14 defines certified reference material and its documented property values, uncertainties and traceabilities.
Additional VIM3 locators: Entry 2.9, measurement result, notes 1–3; Entry 2.5, measurement method, note and annotation of 11 June 2015; Entry 3.10, measuring chain and examples 1–2. Entries 5.13 and 5.14 distinguish reference materials and certified reference materials: 5.13, note 2 and 5.14, notes 1 and 3–4.
Additional VIM3 locators: Entry 2.4, measurement principle, definition and physical example 1; Entry 2.10, measured quantity value, note 1 and annotation of 9 December 2016; Entry 3.7, measuring transducer, definition and examples.
Additional VIM3 locators: Entry 4.1, indication, definition and notes 1–2; Entry 4.12, sensitivity, definition and notes 1–2.
Additional verified locator: jcgm.bipm.org/vim/en/4.18.html , VIM3 entry 4.18, detection limit. The definition specifies a probability beta of falsely claiming absence at a given probability alpha of falsely claiming presence; note 1 gives IUPAC default values alpha = beta = 0.05. An observed decision threshold and a signal level meeting both error-probability criteria are distinct quantities.
Journal of Research of NIST99(2),121–141 (March–April1994), primary byline Steve R. Domen. Sections1–2: temperature-rise principle, two-thermistor bridge and glass assembly; Abstract and results: dissolved-gas heat-defect investigation. Original full text: pmc.ncbi.nlm.nih.gov/articles/PMC8345238/ .
A Review of NIST Primary Activity Standards for 18F: 1982 to 2013 by Denis E. Bergeron and others by
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Original NIST author account in Journal of Research of NIST119(2014),371–396; DOI10.6028/jres.119.013. First-page byline verifies Denis E.Bergeron as first author. Section2.1 describes conversion of ionizing radiation to scintillation light and photomultiplier detection; section2.1.1 distinguishes efficiency from count rate. The cited section distinguishes the measured count rate from the activity inferred through a detection-efficiency model.
Massic Activity Ratios of the NBS/NIST Tritiated-Water Standards Issued Between 1954 and 1999 by L. L. Lucas by
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Primary paper by L.L.Lucas, Journal of Research of NIST105(4),535–539(2000); DOI10.6028/jres.105.042. Full text pmc.ncbi.nlm.nih.gov/articles/PMC4877154/ . Abstract: liquid-scintillation measurement of massic-activity ratios; comparison with ratios from gravimetric dilution, with agreement within stated uncertainties. Initial-only byline retained.
Calibration of the National Institute of Standards and Technology tritiated-water standards by M. P. Unterweger and others by
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M. P. Unterweger and L. L. Lucas, Applied Radiation and Isotopes52(3),527–531(2000). Primary abstract indexed at pubmed.ncbi.nlm.nih.gov/10724401/ ; NIST publication record www.nist.gov/publications/calibration-national-institute-standards-and-technology-tritiated-water-standards . Verified: gas-proportional counting, liquid-scintillation intercomparisons, SRM4927 activity record over38years and measured half-life4504±9days(one standard deviation). Initial-only author header preserved.
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





