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Record W2000567534 · doi:10.1080/14786430310001593456

A mechanism for spontaneous relaxation of glass at room temperature

2003· article· en· W2000567534 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.

Bibliographic record

VenueThe Philosophical Magazine A Journal of Theoretical Experimental and Applied Physics · 2003
Typearticle
Languageen
FieldMaterials Science
TopicGlass properties and applications
Canadian institutionsMcMaster University
FundersSecretário de Ciência, Tecnologia e Ensino Superior, Governo do Estado de Parana
KeywordsRelaxation (psychology)Materials scienceActivation energyGlass transitionThermodynamicsSilicateDissipationStress relaxationKineticsStrain rateAtom (system on chip)Composite materialChemistryCreepPhysical chemistryPhysics

Abstract

fetched live from OpenAlex

Silicate glasses kept at ambient temperature densify spontaneously, and their properties change with time. This is known as ageing of a glass. The spontaneous change occurs according to first-order rate kinetics, with a characteristic (relaxation) time much shorter than that of the α-relaxation process. According to the mechanism proposed here, there are local regions in the network structure of a silicate glass which collapse spontaneously with time by simultaneous motions of atoms seen as β or the Johari-Goldstein relaxation. The collapse causes the Si-O-Si bond angles in the immediate surroundings to change, and these angles become elastically strained. This strain biases the potential energy in a two-site model for oxygen-atom displacement, which occurs at a faster rate and rapidly dissipates the strain. Thus the glass densifies homogeneously on ageing, by two processes: process I, spontaneous collapse of local regions; process II, subsequent dissipation of strain energy resulting from the collapse. The first process, which is much slower, determines the kinetics of ageing. A fictive temperature Tf,β corresponding to the freezing out of the localized motions of the Johari-Goldstein relaxation process is proposed. For silicate glasses, Tf,β is 40-45% of the usual fictive temperature for the α-relaxation process. The volume lost during ageing may be recovered on heating the aged glass to a temperature far below T g in a time- and temperature-dependent manner, as has already been found from zero-point measurements of a glass thermometer.

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)0.000
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: Theoretical or conceptual · Consensus signal: none
GenreCandidate signal: Empirical · Consensus signal: Empirical
Teacher disagreement score0.009
Threshold uncertainty score0.369

Codex and Gemma teacher scores by category

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

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 head0.012
GPT teacher head0.238
Teacher spread0.225 · 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