Physical Transformation AtlasPTA
Pathway · p-754ea47b1a · candidate

Concentration gradient → Useful heat

Concentration gradientDufour effectHeat flowUseful heat

Epistemic state of the route

known constituent relations
3 / 3 established or replicated · weakest constituent established
constituent maturity floor
K4 · experimentally observed
search for this exact route
Not assessed — complete composition not searched.
recorded-pathway overlap
none recorded
route-level evidence
0 sources for the complete composition · 3 cited by the constituent steps
boundaries and interfaces
BOUNDARY unknown · no scoped condition requirements recorded

Explorematrix context · physics checks · steps · route evidence · constituent evidence · cite

Matrix context

D = disequilibrium row · C = coupling family column. A cell reads the state of the atlas for that pair.

D.03 × C.33 · Concentration gradient × Thermodiffusivefamily: Thermodiffusive

Typed bounds on this route

Every limit the atlas holds for this route, as constraint records: reached through bounded_by claims on the route's own entities. Hard bounds (an upper bound or a formula) decide the thermodynamic-bound check above; benchmarks, constitutive relations and resource limits are listed and never decisive. No prose limit exists anywhere (pass 42).

  • Onsager–Casimir reciprocity · constitutive-relation · listed, never decisive
    L_ij(B) = ε_i ε_j L_ji(−B): the cross-coefficients of coupled linear transport are equal up to the time-reversal parities ε of the variables and reversal of the magnetic field; L_ij = L_ji is the zero-field, even-parity case

Steps

  1. 01
    chemical → thermal
    • a composition gradient in a liquid or gas mixture; the heat flux is the Onsager-reciprocal partner of Soret thermodiffusion
    refs [1] [2]
  2. 02
    Dufour effect —produces→ Heat flowestablishedclaim record
    thermal → thermal
    refs [1] [2]
  3. 03
    Heat flow —converts into→ Useful heatestablishedclaim record
    thermal → thermal
    • heat delivered at a temperature above the point of use
    refs [3]

Evidence for the complete composition · 0

No source on record for this exact composition. The sources below support the individual steps, not the route as a whole.

Evidence for the constituent relations · 3

  1. [1]
    R. L. Rowley, F. H. Horne. The Dufour effect. II. Experimental confirmation of the Onsager heat–mass reciprocal relation for a binary liquid mixture (1978)
    The Journal of Chemical Physics 68, 325-326 · doi:10.1063/1.435458 · crossref ✓ 2026-09-20 · record
  2. [2]
    S. R. de Groot, P. Mazur. Non-Equilibrium Thermodynamics (1962)
    North-Holland · book, no DOI · record
  3. [3]
    A. Bejan. Advanced Engineering Thermodynamics (4th ed.) (2016)
    Wiley · doi:10.1002/9781119245964 · crossref ✓ 2026-09-19 · record

Cite this route

Physical Transformation Atlas (2026). route p-754ea47b1a: Concentration gradient → Dufour effect → Heat flow → Useful heat. Dataset revision rbfbfcbb70e57 (hash of the canonical data). https://physical-transformation-atlas.wldud5192.workers.dev/path/754ea47b1a

Ids and matrix addresses are stable across revisions; the revision hash identifies the exact canonical files the record was compiled from and is meta.data_hash in every /api export. Reuse terms: see the license field in any export.