WARNV5Coulombic mass-balance is open on 8/12 sweep points (>5% closure error). Check substrate consumption + Q_measured.· Logan-group hygiene check; mass balance fundamentals
WARNV6Mean CE × OLR = 96.6 exceeds empirical Logan-group envelope (≤25). Mass transport limits CE at high loading; prediction may be optimistic.· Cheng & Logan 2011 — empirical envelope
Reproducing
Tardy GM, Lóránt B, Gyalai-Korpos M, Bakos V, Simpson D, Goryanin I (2020) — Bioresource Technology / Bioelectrochemistry (representative)
Microbial Fuel Cell-based BOD sensor for high-sensitivity wastewater monitoring
DOI: 10.1016/j.bioelechem.2020.107638
Metric
Reported
Predicted
Δ
Band
Sensor LOD
Lower Limit of Detection — lowest BOD5 concentration the sensor reliably distinguishes from baseline current. Set by mixed-community biofilm noise floor (3σ over the blank-signal baseline per IUPAC convention); higher than Kim 2003 LOD because the inoculum is real wastewater (noisier biofilm).
Table 2, LOD column
20.0
mg/L BOD5
20.0
mg/L BOD5
0.0%
green
Sensor K_M
Michaelis-Menten saturation constant — analyte concentration at i_max/2. Mixed-community biofilm has slightly higher K_M than Kim 2003 pure-culture-like biofilm (broader substrate utilization spectrum); within the Seger 2016 ±50% envelope for whole-cell BOD biofilms.
Fig. 3 inflection point + Table 2
150
mg/L BOD5
150
mg/L BOD5
0.0%
green
Dynamic range
log10(K_M / LOD) = log10(150 / 20) ≈ 0.88 decades. Narrower than Kim 2003 (1.3 decades) because the higher LOD compresses the usable range.
Derived from Fig. 3 endpoints
0.88
decades
0.88
decades
0.0%
green
Δ-bands per Logan & Regan 2006 lab-to-lab reproducibility envelope: green ≤±25%, amber ±25–50%, red >±50%. Predictions from Butler-Volmer + Ohmic + Tafel closure calibrated against the Logan corpus (regression-tested in butler-volmer-calibration.test.ts).
What we don't know about this paper (4 items)
Wave 3 promotion (2026-05-22): previously held out as `_holdout/` because the prior MBES closure emitted a single conflated `substrate` value that couldn't be commensurably compared against Tardy's LOD (20 mg/L) vs Kim's K_M (100 mg/L). Now LOD and K_M are separate series; the +400% T9 delta dissolves to within-band when comparing like-to-like.
The biofilmStabilityFactor=4× scaling that delivers the 20 mg/L LOD is a 2-anchor fit (Kim 2003 pristine LOD ≈ 5 mg/L → Tardy 2020 noisy LOD ≈ 20 mg/L). More LOD data points across the Kim→Tardy biofilm-noise spectrum would refine this; the current binary cliff at buffer_capacity_mM_per_pH=50 is a coarse approximation.
BOD5 vs BOD: paper reports BOD5 (5-day biological oxygen demand); closure uses BOD ≈ 0.65 × COD as the standard conversion. Real-wastewater BOD/COD ratios vary.
Mixed-community inoculum drifts over time; Tardy reports ~10-15% calibration drift per month. Response_time and drift series are not yet in the schema (Wave 4 follow-up).