{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T11:12:37Z","timestamp":1788433957747,"version":"build-2803163510"},"reference-count":30,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2026,8,28]],"date-time":"2026-08-28T00:00:00Z","timestamp":1787875200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Open Access Publication Fund of OTH Regensburg"},{"id":[{"id":"https:\/\/ror.org\/04b9vrm74","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Ammonia is increasingly considered a promising hydrogen carrier due to its high hydrogen density and well-established infrastructure. Monitoring ammonia cracking efficiency requires robust, continuous gas analysis across a wide concentration range, with resistance to corrosive gases. Conventional methods such as gas chromatography or mass spectrometry meet these requirements, but are costly and operationally complex. To address this gap, a Thermal Conductivity Analyzer (TCA) was developed based on an OEM module and validated for continuous in situ monitoring of ammonia cracking. The system includes a pump-driven bypass extraction line and a three-stage calibration procedure: zero-point correction, look-up table generation, and span calibration. Measurement stability was assessed using binary H2\/N2 mixtures and a quasi-binary surrogate of the ammonia cracking product gas, mixed via mass flow controllers (MFCs). The analyzer was then applied to characterize a monolithic ammonia cracking catalyst from 200\u2013650 \u00b0C. With daily zero-point and span calibration, all measured H2 concentrations fell within the mixing uncertainty of the MFCs across 0\u2013100 vol.%. For the synthetic cracking gas, maximum conversion ratio deviations of +0.317 and \u22120.224 percentage points were achieved. These results demonstrate that the TCA offers a simple, ammonia-resistant alternative for monitoring NH3 cracking processes, with uncertainties competitive with MFC repeatability.<\/jats:p>","DOI":"10.3390\/s26175463","type":"journal-article","created":{"date-parts":[[2026,8,31]],"date-time":"2026-08-31T05:55:56Z","timestamp":1788155756000},"page":"5463","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Development and Validation of an Ammonia-Resistant Thermal-Conductivity Analyzer for In Situ Monitoring of NH3-Cracking-Processes"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0009-0004-9691-5869","authenticated-orcid":false,"given":"Lucas","family":"Ott","sequence":"first","affiliation":[{"name":"Technology Campus (TC) Kelheim, Ostbayerische Technische Hochschule (OTH) Regensburg, Hopfenbachweg 4, 93309 Kelheim, Germany"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"software","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-6480-6941","authenticated-orcid":false,"given":"Ottfried","family":"Schmidt","sequence":"additional","affiliation":[{"name":"Technology Campus (TC) Kelheim, Ostbayerische Technische Hochschule (OTH) Regensburg, Hopfenbachweg 4, 93309 Kelheim, Germany"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"software","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-8152-793X","authenticated-orcid":false,"given":"Hans-Peter","family":"Rabl","sequence":"additional","affiliation":[{"name":"Technology Campus (TC) Kelheim, Ostbayerische Technische Hochschule (OTH) Regensburg, Hopfenbachweg 4, 93309 Kelheim, Germany"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"validation","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"881","DOI":"10.3390\/cleantechnol3040051","article-title":"Hydrogen as a Clean and Sustainable Energy Vector for Global Transition from Fossil-Based to Zero-Carbon","volume":"3","author":"Guilbert","year":"2021","journal-title":"Clean Technol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"7746","DOI":"10.1016\/j.ijhydene.2019.01.144","article-title":"Reversible ammonia-based and liquid organic hydrogen carriers for high-density hydrogen storage: Recent progress","volume":"44","author":"Makepeace","year":"2019","journal-title":"Int. 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