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Record W1938901960 · doi:10.1002/xrs.2629

The quantification of total lead in lipstick specimens by total reflection X‐ray fluorescence spectrometry

2015· article· en· W1938901960 on OpenAlex

Why this work is in the frame

A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.

affAt least one author lists a Canadian institution in the pinned OpenAlex snapshot.
fundA Canadian funder is recorded on the work.

Bibliographic record

VenueX-Ray Spectrometry · 2015
Typearticle
Languageen
FieldArts and Humanities
TopicCultural Heritage Materials Analysis
Canadian institutionsToronto Metropolitan University
FundersNatural Sciences and Engineering Research Council of Canada
KeywordsLipstickDetection limitX-ray fluorescenceMaterials scienceAnalytical Chemistry (journal)YttriumChemistryChromatographyMineralogyFluorescenceOpticsMetallurgyPhysics

Abstract

fetched live from OpenAlex

Lipstick is known to contain lead, and this has been a general area of concern. Methods of quantifying lead in lipstick currently require the use of rather harsh digestion procedures given that lipstick specimens are high in their lipid content and contain many refractory materials. A simple method of performing lead analysis in lipstick specimens based on total reflection X‐ray fluorescence spectrometry (TXRF) is presented here. Samples were prepared by melting lipstick specimens along with a non‐ionic surfactant and an yttrium internal standard followed by homogenization. Solid prepared samples were then finely streaked directly onto a quartz reflector, and TXRF measurements made for 900‐s live time. The method was found to produce a mean limit of detection for lead of 0.04μg/g. Precisions were found to be on the order of 11–38% relative standard deviation (RSD) and apparent recoveries for lead between 92% and 106% ( n = 8). Although the spreading technique may result in thickness variations that may contribute to the higher than expected variances about the determined lead concentrations, the method presented in this work does show promise as a means of performing routine lead analysis in lipstick specimens without the need for harsh digestion procedures. Copyright © 2015 John Wiley & Sons, Ltd.

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.

Full frame distilled prediction

Teacher imitation

Not calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.

metaresearch head score (Codex)0.001
metaresearch head score (Gemma)0.000
Version: codex-gemma-dda1882f352aValidation status: machine_predicted_unvalidated
Candidate categoriesnone
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Bench or experimental · Consensus signal: Bench or experimental
GenreCandidate signal: Empirical · Consensus signal: Empirical
Teacher disagreement score0.302
Threshold uncertainty score0.981

Codex and Gemma teacher scores by category

CategoryCodexGemma
Metaresearch0.0010.000
Meta-epidemiology (narrow)0.0000.000
Meta-epidemiology (broad)0.0000.000
Bibliometrics0.0000.001
Science and technology studies0.0000.000
Scholarly communication0.0000.000
Open science0.0000.000
Research integrity0.0000.000
Insufficient payload (model declined to judge)0.0010.000

Machine scores (provisional)

The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.

Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.

Opus teacher head0.043
GPT teacher head0.261
Teacher spread0.218 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it