{ "vercy": "1.0-draft", "publication": { "status": "research-draft", "adjudicationStatus": "unreviewed", "publishableCanonical": false, "generatedAt": "2026-09-12T09:26:18Z", "providers": [ "Codex" ], "breadth": "recalled by Codex without web access - no source was read", "missingProviders": [], "pass": 2, "cost": { "grok": { "seconds": 18.9, "error": "Reading additional input from stdin...\nOpenAI Codex v0.153.4\n--------\nworkdir: R:\\02_PROJECTS\\02_Meta_Models_Platforms\\Ver.cy\\current\\thing-registry-backlog\nmodel: gpt-6-astra\nprovider: openai\napproval: never\nsandbox: read-only\nreasoning effort: none\nreasoning summaries: none\nsession id: 01a094ef-149c-72c1-9b81-32daefd68eda\n--------\nuser\nDescribe what is already known about one registered thing. Answer as JSON only, no prose around it.\n\nThing: egtazic acid\nSense to describe: (none recorded)\nDomain code: PHY.MAT\nAlso known as: (none)\n\n\nContext for this batch of 1001 things:\n# Batch 043: 1001 re", "usd": 0.0, "recall": true }, "codex": { "seconds": 87.6, "error": "Reading additional input from stdin...\nOpenAI Codex v0.153.4\n--------\nworkdir: R:\\02_PROJECTS\\02_Meta_Models_Platforms\\Ver.cy\\current\\thing-registry-backlog\nmodel: gpt-6-astra\nprovider: openai\napproval: never\nsandbox: read-only\nreasoning effort: none\nreasoning summaries: none\nsession id: 01a094ef-148c-7033-95dd-3c0acb462624\n--------\nuser\nYou are drafting a Vercy meta-model for one registered thing. Answer as JSON only, no prose around it.\n\nThing: egtazic acid\nRegistry id: vr.tr.egtazic-acid\nPlane / domain: PHY / PHY.MAT\nRegistry definition: (none recorded)\nNames folded into this entry: (none)\n" } }, "enrichment": { "pass": 3, "engine": "claude", "producedAt": "2026-10-06T12:00:00Z", "ingestedAt": "2026-10-06T08:50:42+00:00", "fields": [ "agent_conduct", "ethics", "failure_modes_and_hazards", "owners", "standards_and_regulation", "visual_identification" ] }, "gate": { "passed": true, "version": "1.0", "at": "2026-10-07T10:10:30+00:00", "evidence": [ "completeness 1.00", "sense: Wikidata description", "2 live sources", "review by codex: pass" ] } }, "metaModel": { "id": "THING-Q408437", "registryId": "vr.tr.egtazic-acid", "name": "egtazic acid", "version": "0.1.0-research.1", "entryKind": "thing", "family": "Thing Registry", "domain": [ "PHY.MAT" ], "status": "research-draft" }, "canonicalUrl": "https://ver.cy/models/thing/q408437/", "model": { "registry_id": "vr.tr.egtazic-acid", "name": "egtazic acid", "purpose": "Enable an agent to recognise egtazic acid, assess its material and calcium-binding state, and determine its suitability for a specified laboratory use.", "definition": "Egtazic acid, commonly called EGTA, is an aminopolycarboxylic acid chelating agent used to bind calcium ions preferentially over magnesium ions under appropriately controlled solution conditions.", "scope_statement": "This model owns the chemical identity, material quality, solution speciation, chelation behaviour and handling constraints of egtazic acid under registry entry vr.tr.egtazic-acid, distinguishing the parent substance from salts, metal complexes and formulated products.", "in_scope": [ "Egtazic acid identity and synonyms, including EGTA", "Free-acid composition, purity, water content and metal contamination", "Physical state, dissolution and condition-dependent properties", "Protonation, calcium binding and competition from magnesium and other metals", "Material suitability for calcium buffering and chelation", "Form-specific hazard evidence, storage and disposal constraints" ], "out_of_scope": [ "Independent chemical identities of EGTA salts and isolated metal complexes", "Complete buffer formulations and commercial reagent products", "Biological systems and their responses to calcium depletion", "Experimental apparatus and complete assay protocols", "Industrial synthesis processes", "Clinical treatment decisions and medicinal product authorisations" ], "distinguishing_features": [ "Resolve egtazic acid and EGTA to the parent identity CAS 67-42-5 and PubChem CID 6207; an acronym alone is insufficient identification. [PubChem](https://pubchem.ncbi.nlm.nih.gov/compound/egta)", "Check for the free-acid formula C14H24N2O10 and molar mass 380.35 g/mol before converting mass to amount. [PubChem](https://pubchem.ncbi.nlm.nih.gov/compound/egta)", "Distinguish EGTA from edetic acid by its molecular connectivity, including two ether linkages, rather than treating all aminopolycarboxylate chelators as interchangeable. [PubChem](https://pubchem.ncbi.nlm.nih.gov/compound/egta)", "Evaluate calcium chelation in the presence of magnesium under specified conditions; this is a characteristic application of EGTA, but does not establish unconditional metal specificity. [Sigma-Aldrich](https://www.sigmaaldrich.com/NI/en/product/sial/e4378)", "Check counterions and protonation before equating an EGTA-labelled preparation with the free acid; EGTA tetrasodium has a distinct composition and compound record. [PubChem](https://pubchem.ncbi.nlm.nih.gov/compound/EGTA-tetrasodium)" ], "characteristics": [ { "name": "Parent chemical identity", "kind": "category", "unit_or_values": "Egtazic acid / EGTA; CAS 67-42-5; PubChem CID 6207", "why_it_matters": "Anchors synonym resolution and prevents confusion with related chelators. [PubChem](https://pubchem.ncbi.nlm.nih.gov/compound/egta)" }, { "name": "Material form", "kind": "category", "unit_or_values": "Free acid; salt-associated preparation; dissolved species; metal-loaded preparation", "why_it_matters": "Determines whether parent-substance calculations apply and which neighbouring substance or mixture records are needed." }, { "name": "Assay purity and water content", "kind": "measurement", "unit_or_values": "Mass %, with analytical method and as-received or dry basis", "why_it_matters": "Controls the amount of active ligand delivered by a weighed sample." }, { "name": "Residual metal content", "kind": "measurement", "unit_or_values": "µmol metal/g material or mg/kg, resolved by element", "why_it_matters": "Pre-existing metal loading can reduce available binding capacity and bias calcium-buffer preparation." }, { "name": "Total analytical EGTA concentration", "kind": "measurement", "unit_or_values": "mol/L, including protonated, unbound and metal-bound ligand", "why_it_matters": "Supports ligand mass balance without confusing total EGTA with available binding sites." }, { "name": "Solution conditions", "kind": "state", "unit_or_values": "pH; temperature in °C; ionic strength in mol/L; solvent and buffer composition", "why_it_matters": "Defines the conditions under which dissolution and equilibrium estimates are applicable." }, { "name": "Conditional metal affinity", "kind": "measurement", "unit_or_values": "Conditional Kd in mol/L, or explicitly defined formation constant, per metal and condition set", "why_it_matters": "Prevents use of an intrinsic constant as if it directly predicted binding in an experimental buffer." }, { "name": "Metal occupancy", "kind": "measurement", "unit_or_values": "mol bound metal/mol total EGTA, resolved by metal", "why_it_matters": "Distinguishes total ligand quantity from remaining chelation capacity." }, { "name": "Free calcium concentration", "kind": "measurement", "unit_or_values": "mol/L or pCa = -log10([Ca2+]/1 mol/L), with measured or calculated status", "why_it_matters": "Expresses the calcium-control outcome rather than merely the amount of calcium or EGTA added." }, { "name": "Applicable safety and regulatory record", "kind": "relation", "unit_or_values": "Material-specific SDS, supplier, revision, jurisdiction and verified inventory identifiers", "why_it_matters": "Connects handling decisions to the actual material form and current evidence." } ], "affordances": [ "Resolve an EGTA-labelled material to the parent acid or a linked salt, complex or formulation.", "Calculate ligand amount from mass using verified form, assay and water content.", "Assess whether a proposed stock concentration is soluble under its specified conditions.", "Estimate calcium binding and competing-metal effects using condition-matched equilibrium data.", "Select or reject a lot for a calcium-sensitive experiment using contamination and capacity evidence.", "Determine handling, storage and disposal requirements from the applicable material record." ], "agent_conduct": { "may": [ "Describe EGTA and its use as a calcium chelator in laboratory buffers.", "Report hazard and storage information from a safety data sheet.", "Track stock in a laboratory the agent is authorized to manage." ], "must_not": [ "Recommend EGTA for use in people or as a supplement.", "Confuse EGTA with EDTA in orders, protocols or records.", "Dispose of it outside the laboratory's chemical waste process." ], "requires_human": [ "Changing a validated protocol that depends on its calcium binding." ] }, "ethics": { "considerations": [ "Mix-ups between chelators can spoil experiments and waste research resources." ], "affected_parties": [ "Laboratory workers", "Researchers relying on results" ] }, "owners": { "steward": "The laboratory that holds it.", "master_systems": [ "Chemical inventories and safety data sheet systems" ] }, "visual_identification": [ "A white crystalline powder supplied in labelled reagent bottles." ], "failure_modes_and_hazards": [ "Can irritate eyes, skin and airways.", "Confusion with EDTA changes how calcium and magnesium are bound in an experiment." ], "standards_and_regulation": [ "Globally Harmonized System of Classification and Labelling of Chemicals (GHS), United Nations." ], "what_it_is_for": [ "Egtazic acid is used in biochemical and cell physiology laboratories to control available calcium in solutions.", "Its preferential binding of calcium over magnesium supports experiments that distinguish calcium-dependent processes under controlled solution conditions.", "It is also encountered in sample preparation and analytical work where metal binding affects the interpretation of results." ] }, "sources": [ { "id": "wikidata", "title": "Wikidata item Q408437: egtazic acid", "url": "https://www.wikidata.org/wiki/Q408437", "url_status": "live", "what_it_supports": "identity and sense of the item", "checked_by": "wikidata-api" }, { "id": "wikipedia-en", "title": "Wikipedia: EGTA", "url": "https://en.wikipedia.org/wiki/EGTA", "url_status": "live", "what_it_supports": "general description of the item", "checked_by": "wikidata-api sitelink" } ], "structure": { "bundles": [ { "id": "identity-and-form", "name": "Identity and form", "description": "Establish what an egtazic-acid label identifies and which chemical forms it includes.", "rationale": "The EGTA name can accompany parent acid, neutralised stocks and metal-containing preparations that require different calculations.", "layers": [ { "id": "parent-identity", "name": "Parent identity", "description": "Resolve names and identifiers against molecular structure.", "findings": [ { "id": "egtazic-acid-name-resolution", "name": "Egtazic acid name resolution", "description": "Require agreement between the supplied name, parent identifier and chemical structure.", "questions": [ { "text": "Does the material record identify egtazic acid as EGTA with CAS 67-42-5 and a matching structure?", "kind": "definition", "id": "egtazic-acid-name-resolution-q01" }, { "text": "Which authoritative record establishes its identifiers, including any verified EC number?", "kind": "provenance", "id": "egtazic-acid-name-resolution-q02" } ] } ] }, { "id": "acid-salt-complex-boundary", "name": "Acid, salt and complex boundary", "description": "Separate parent identity from counterions, protonation and bound metals.", "findings": [ { "id": "declared-egta-form", "name": "Declared EGTA form", "description": "Identify the form actually supplied or present before choosing a formula mass or interpreting an assay.", "questions": [ { "text": "Is the supplied material free acid, a defined salt, a metal complex or an EGTA-containing mixture?", "kind": "boundary", "id": "declared-egta-form-q01" }, { "text": "Which counterions, hydration state and prebound metals must be included in its composition?", "kind": "measurement", "id": "declared-egta-form-q02" }, { "text": "Which related forms need linked records rather than becoming aliases of the parent acid?", "kind": "boundary", "id": "declared-egta-form-q03" } ] } ] } ] }, { "id": "lot-quality-and-capacity", "name": "Lot quality and capacity", "description": "Characterise how much usable EGTA a particular material supplies.", "rationale": "Nominal mass and catalogue grade do not establish effective chelation capacity.", "layers": [ { "id": "assay-and-mass-basis", "name": "Assay and mass basis", "description": "Establish ligand content independently of moisture and other material.", "findings": [ { "id": "effective-ligand-content", "name": "Effective ligand content", "description": "Relate reported purity to its analytical method and the basis used for weighing.", "questions": [ { "text": "What EGTA assay and water content are reported for this lot, and on what mass basis?", "kind": "measurement", "id": "effective-ligand-content-q01" }, { "text": "Does the assay measure molecular purity, titratable acidity or metal-binding capacity?", "kind": "definition", "id": "effective-ligand-content-q02" } ] } ] }, { "id": "metal-background", "name": "Metal background", "description": "Account for contamination and prior metal loading.", "findings": [ { "id": "available-chelation-capacity", "name": "Available chelation capacity", "description": "Assess whether metals already present materially change ligand availability.", "questions": [ { "text": "What calcium, magnesium and other relevant metal concentrations are present in the lot or stock?", "kind": "measurement", "id": "available-chelation-capacity-q01" }, { "text": "What acceptance limit for metal background follows from the intended free-calcium target?", "kind": "action", "id": "available-chelation-capacity-q02" } ] } ] } ] }, { "id": "physical-state-and-stock-preparation", "name": "Physical state and stock preparation", "description": "Describe the solid material and the conditions needed for a characterised solution.", "rationale": "Dissolution, neutralisation and stock composition must be resolved before EGTA concentration is operationally meaningful.", "layers": [ { "id": "solid-state-properties", "name": "Solid-state properties", "description": "Associate observed appearance and thermal properties with a defined material form.", "findings": [ { "id": "physical-property-evidence", "name": "Physical property evidence", "description": "Require conditions and methods for phase and thermal claims rather than copying isolated constants.", "questions": [ { "text": "What physical state and appearance are observed for the identified lot at the recorded temperature?", "kind": "measurement", "id": "physical-property-evidence-q01" }, { "text": "Do reported thermal values describe melting, decomposition or another event, and is a boiling point experimentally meaningful?", "kind": "provenance", "id": "physical-property-evidence-q02" } ] } ] }, { "id": "dissolution-and-neutralisation", "name": "Dissolution and neutralisation", "description": "Track concentration, pH and counterions introduced during stock preparation.", "findings": [ { "id": "defined-egta-stock", "name": "Defined EGTA stock", "description": "Treat a stock as a characterised solution whose pH and added base affect subsequent use.", "questions": [ { "text": "What EGTA concentration is demonstrably dissolved at the specified pH, temperature and solvent composition?", "kind": "measurement", "id": "defined-egta-stock-q01" }, { "text": "Which base and amount were used, and what counterion concentration resulted?", "kind": "provenance", "id": "defined-egta-stock-q02" }, { "text": "What check confirms complete dissolution and final concentration before the stock is used?", "kind": "action", "id": "defined-egta-stock-q03" } ] } ] } ] }, { "id": "protonation-and-metal-equilibria", "name": "Protonation and metal equilibria", "description": "Represent EGTA binding as a condition-dependent competition among protonation and metal-complexation states.", "rationale": "A single affinity value cannot determine free calcium across different buffers.", "layers": [ { "id": "protonation-state", "name": "Protonation state", "description": "Establish how acid-base equilibria enter the binding calculation.", "findings": [ { "id": "applicable-acid-base-data", "name": "Applicable acid-base data", "description": "Select protonation data and conventions appropriate to the actual solution.", "questions": [ { "text": "Which protonation constants apply at the stated temperature and ionic strength?", "kind": "provenance", "id": "applicable-acid-base-data-q01" }, { "text": "How does the calculation account for protonated uncomplexed EGTA at the measured pH?", "kind": "definition", "id": "applicable-acid-base-data-q02" } ] } ] }, { "id": "competitive-metal-binding", "name": "Competitive metal binding", "description": "Evaluate calcium binding alongside magnesium and other competing ions.", "findings": [ { "id": "condition-matched-affinities", "name": "Condition-matched affinities", "description": "Distinguish intrinsic formation constants from conditional affinities and document the species included.", "questions": [ { "text": "What calcium and magnesium binding constants are supported under the intended conditions, and how are those constants defined?", "kind": "measurement", "id": "condition-matched-affinities-q01" }, { "text": "Which additional metals or ligands must be included to avoid overstating calcium selectivity?", "kind": "boundary", "id": "condition-matched-affinities-q02" }, { "text": "What complex stoichiometries and species are justified in the equilibrium model?", "kind": "definition", "id": "condition-matched-affinities-q03" } ] } ] } ] }, { "id": "calcium-control-and-use-fitness", "name": "Calcium control and use fitness", "description": "Connect a defined EGTA preparation to a measurable calcium-control objective.", "rationale": "An agent must distinguish adding chelator from achieving and maintaining the required free-calcium state.", "layers": [ { "id": "calcium-mass-balance", "name": "Calcium mass balance", "description": "Separate total calcium, free calcium and EGTA-bound calcium.", "findings": [ { "id": "free-calcium-target", "name": "Free-calcium target", "description": "Evaluate a target using the complete ligand and metal inventories with uncertainty.", "questions": [ { "text": "What total EGTA, total calcium and background-metal amounts enter the calculation?", "kind": "measurement", "id": "free-calcium-target-q01" }, { "text": "What free-calcium concentration is predicted, and how sensitive is it to pH, contamination and concentration uncertainty?", "kind": "measurement", "id": "free-calcium-target-q02" }, { "text": "What independent measurement or reference preparation will validate the predicted calcium state?", "kind": "action", "id": "free-calcium-target-q03" } ] } ] }, { "id": "experimental-compatibility", "name": "Experimental compatibility", "description": "Assess whether EGTA can deliver the intended effect within the experiment's conditions and timescale.", "findings": [ { "id": "chelation-fitness", "name": "Chelation fitness", "description": "Require use-specific evidence for equilibration and tolerance of altered metal availability.", "questions": [ { "text": "Does EGTA reach the relevant compartment and bind calcium quickly enough for the intended observation?", "kind": "boundary", "id": "chelation-fitness-q01" }, { "text": "Which required metal-dependent activities could be affected by this EGTA concentration?", "kind": "boundary", "id": "chelation-fitness-q02" }, { "text": "What control or acceptance criterion establishes that EGTA is suitable for this use?", "kind": "action", "id": "chelation-fitness-q03" } ] } ] } ] }, { "id": "handling-storage-and-disposition", "name": "Handling, storage and disposition", "description": "Tie handling decisions to the identified EGTA material and its current composition.", "rationale": "Dry acid, alkaline stocks and metal-loaded waste require distinct evidence for handling and disposition.", "layers": [ { "id": "form-specific-safety", "name": "Form-specific safety", "description": "Identify applicable hazard and exposure information without transferring it between different preparations.", "findings": [ { "id": "applicable-hazard-record", "name": "Applicable hazard record", "description": "Resolve classification and controls from records that match the material form and jurisdiction.", "questions": [ { "text": "Which current SDS and jurisdiction-specific classification apply to this free acid or EGTA-containing solution?", "kind": "provenance", "id": "applicable-hazard-record-q01" }, { "text": "What exposure limits are established, if any, and which handling controls follow from the applicable record?", "kind": "action", "id": "applicable-hazard-record-q02" } ] } ] }, { "id": "stock-integrity-and-waste", "name": "Stock integrity and waste", "description": "Track changes that invalidate stock suitability and account for bound metals at disposal.", "findings": [ { "id": "storage-requalification", "name": "Storage requalification", "description": "Define when a stored EGTA preparation remains acceptable or needs rechecking.", "questions": [ { "text": "What evidence supports the storage conditions and usable lifetime for this EGTA form and preparation?", "kind": "provenance", "id": "storage-requalification-q01" }, { "text": "Which changes in pH, precipitation, contamination or binding capacity require requalification or rejection?", "kind": "action", "id": "storage-requalification-q02" } ] }, { "id": "metal-containing-waste", "name": "Metal-containing waste", "description": "Assess spent EGTA by its actual metals, additives and pH.", "questions": [ { "text": "Which metals and other hazardous constituents are present in the spent EGTA solution?", "kind": "measurement", "id": "metal-containing-waste-q01" }, { "text": "Which disposal route is permitted for that composition under the applicable local rules?", "kind": "action", "id": "metal-containing-waste-q02" } ] } ] } ] }, { "id": "evidence-and-external-alignment", "name": "Evidence and external alignment", "description": "What the world already says about this thing, gathered so the model can be checked against it.", "rationale": "A model that cannot be lined up against existing standards, identifiers and practice cannot be adopted by anyone who already uses them.", "layers": [ { "id": "reported-evidence", "name": "Reported evidence", "description": "Findings from the breadth pass, kept separate from the structural claims.", "findings": [ { "id": "evidence-confidence-notes", "name": "Check these first", "description": "Recalled without web access and unsourced; every item is a lead to verify.", "evidence": [ "This is recalled information, not a source-verified account.", "Check quantitative binding constants and calcium-buffer calculations for the actual experimental conditions.", "Verify purity, hydration state, physical constants and hazard classification against documentation for the specific chemical form and grade." ], "questions": [ { "id": "evidence-confidence-notes-q01", "text": "Which of these check these first hold for the sense of egtazic acid this model covers, and on what evidence?", "kind": "provenance" } ] }, { "id": "evidence-identifiers", "name": "Identifiers and schemes", "description": "Recalled without web access and unsourced; every item is a lead to verify.", "evidence": [ { "scheme": "CAS Registry Number", "value_or_pattern": "67-42-5", "note": "Identifies the free acid; salts require separate identification." }, { "scheme": "Common chemical abbreviation", "value_or_pattern": "EGTA", "note": "Ethylene glycol-bis(2-aminoethylether)-N,N,N′,N′-tetraacetic acid." }, { "scheme": "Molecular formula", "value_or_pattern": "C14H24N2O10", "note": "Composition of the free acid; not a unique structural identifier." } ], "questions": [ { "id": "evidence-identifiers-q01", "text": "Which of these identifiers and schemes hold for the sense of egtazic acid this model covers, and on what evidence?", "kind": "provenance" } ] }, { "id": "evidence-real-world-use", "name": "Real-world use", "description": "Recalled without web access and unsourced; every item is a lead to verify.", "evidence": [ "Preparing calcium buffers with controlled free calcium concentrations.", "Removing available calcium in biochemical and cell biology experiments.", "Distinguishing calcium-dependent effects from magnesium-dependent effects in experimental systems." ], "questions": [ { "id": "evidence-real-world-use-q01", "text": "Which of these real-world use hold for the sense of egtazic acid this model covers, and on what evidence?", "kind": "provenance" } ] }, { "id": "evidence-measurements", "name": "Typical measurements", "description": "Recalled without web access and unsourced; every item is a lead to verify.", "evidence": [ { "quantity": "Molar mass of the free acid", "typical_range": "380.35", "unit": "g/mol" } ], "questions": [ { "id": "evidence-measurements-q01", "text": "Which of these typical measurements hold for the sense of egtazic acid this model covers, and on what evidence?", "kind": "provenance" } ] }, { "id": "evidence-failure-modes-and-hazards", "name": "Failure modes and hazards", "description": "Recalled without web access and unsourced; every item is a lead to verify.", "evidence": [ "Calcium binding depends on pH, temperature, ionic strength and competing ions; total added calcium does not directly specify free calcium concentration.", "Chelation can suppress calcium-dependent enzymes, signalling and other biological processes, confounding experiments.", "Limited dissolution of the free acid can lead to incorrect stock concentrations unless dissolution and pH are checked.", "Confusing free acid and salt forms can produce concentration errors when weighing reagents." ], "questions": [ { "id": "evidence-failure-modes-and-hazards-q01", "text": "Which of these failure modes and hazards hold for the sense of egtazic acid this model covers, and on what evidence?", "kind": "provenance" } ] }, { "id": "evidence-neighbours", "name": "Neighbouring kinds and how to tell them apart", "description": "Recalled without web access and unsourced; every item is a lead to verify.", "evidence": [ { "name": "EDTA", "difference": "EDTA has a different molecular backbone and generally discriminates less strongly between calcium and magnesium." }, { "name": "BAPTA", "difference": "BAPTA has an aromatic backbone and faster calcium-binding kinetics, making it experimentally distinct from EGTA." }, { "name": "EGTA salts", "difference": "Salts contain counterions and have different formula masses and dissolution behaviour from the registered free acid." } ], "questions": [ { "id": "evidence-neighbours-q01", "text": "Which of these neighbouring kinds and how to tell them apart hold for the sense of egtazic acid this model covers, and on what evidence?", "kind": "provenance" } ] } ] } ] } ] }, "openQuestions": [ "Which protonation and calcium/magnesium equilibrium datasets are sufficiently validated across the pH, temperature and ionic-strength ranges the model should support?", "Which EC identifier, jurisdiction-specific hazard classifications and substance-specific exposure limits can be verified for the parent free acid?", "What reliable measurements establish free-acid solubility and thermal behaviour, including whether reported melting values involve decomposition?", "What lot-level metal contamination and binding-capacity limits are appropriate for different free-calcium targets?", "What evidence establishes stock stability, equilibration times and requalification criteria for the intended laboratory uses?" ], "statistics": { "bundles": 7, "layers": 13, "findings": 19, "questions": 37 } }