{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,4]],"date-time":"2026-03-04T08:10:51Z","timestamp":1772611851749,"version":"3.50.1"},"reference-count":62,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2021,9,14]],"date-time":"2021-09-14T00:00:00Z","timestamp":1631577600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"German Ministry for Education and Research BMBF","award":["05A17VK2"],"award-info":[{"award-number":["05A17VK2"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Highly accurate, quantitative analyses of mixtures of hydrogen isotopologues\u2014both the stable species, H2, D2, and HD, and the radioactive species, T2, HT, and DT\u2014are of great importance in fields as diverse as deuterium\u2013tritium fusion, neutrino mass measurements using tritium \u03b2-decay, or for photonuclear experiments in which hydrogen\u2013deuterium targets are used. In this publication we describe a production, handling, and analysis facility capable of fabricating well-defined gas samples, which may contain any of the stable and radioactive hydrogen isotopologues, with sub-percent accuracy for the relative species concentrations. The production is based on precise manometric gas mixing of H2, D2, and T2. The heteronuclear isotopologues HD, HT, and DT are generated via controlled, in-line catalytic reaction or by \u03b2-induced self-equilibration, respectively. The analysis was carried out using an in-line intensity- and wavelength-calibrated Raman spectroscopy system. This allows for continuous monitoring of the composition of the circulating gas during the self-equilibration or catalytic evolution phases. During all procedures, effects, such as exchange reactions with wall materials, were considered with care. Together with measurement statistics, these and other systematic effects were included in the determination of composition uncertainties of the generated reference gas samples. Measurement and calibration accuracy at the level of 1% was achieved.<\/jats:p>","DOI":"10.3390\/s21186170","type":"journal-article","created":{"date-parts":[[2021,9,14]],"date-time":"2021-09-14T23:34:11Z","timestamp":1631662451000},"page":"6170","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Accurate Reference Gas Mixtures Containing Tritiated Molecules: Their Production and Raman-Based Analysis"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5420-4533","authenticated-orcid":false,"given":"Simon","family":"Niemes","sequence":"first","affiliation":[{"name":"Tritium Laboratory Karlsruhe (TLK), Institute for Astroparticle Physics (IAP), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76021 Karlsruhe, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4839-7310","authenticated-orcid":false,"given":"Helmut H.","family":"Telle","sequence":"additional","affiliation":[{"name":"Departamento de Qu\u00edmica F\u00edsica Aplicada, Campus de Cantoblanco, Universidad Aut\u00f3noma de Madrid, 28049 Madrid, Spain"}]},{"given":"Beate","family":"Bornschein","sequence":"additional","affiliation":[{"name":"Tritium Laboratory Karlsruhe (TLK), Institute for Astroparticle Physics (IAP), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76021 Karlsruhe, Germany"}]},{"given":"Lucian","family":"Fasselt","sequence":"additional","affiliation":[{"name":"Tritium Laboratory Karlsruhe (TLK), Institute for Astroparticle Physics (IAP), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76021 Karlsruhe, Germany"},{"name":"Institut f\u00fcr Physik, Humboldt-Universit\u00e4t zu Berlin, Unter den Linden 6, 10099 Berlin, Germany"}]},{"given":"Robin","family":"Gr\u00f6\u00dfle","sequence":"additional","affiliation":[{"name":"Tritium Laboratory Karlsruhe (TLK), Institute for Astroparticle Physics (IAP), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76021 Karlsruhe, Germany"}]},{"given":"Florian","family":"Priester","sequence":"additional","affiliation":[{"name":"Tritium Laboratory Karlsruhe (TLK), Institute for Astroparticle Physics (IAP), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76021 Karlsruhe, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3091-8088","authenticated-orcid":false,"given":"Magnus","family":"Schl\u00f6sser","sequence":"additional","affiliation":[{"name":"Tritium Laboratory Karlsruhe (TLK), Institute for Astroparticle Physics (IAP), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76021 Karlsruhe, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0479-3258","authenticated-orcid":false,"given":"Michael","family":"Sturm","sequence":"additional","affiliation":[{"name":"Tritium Laboratory Karlsruhe (TLK), Institute for Astroparticle Physics (IAP), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76021 Karlsruhe, Germany"}]},{"given":"Stefan","family":"Welte","sequence":"additional","affiliation":[{"name":"Tritium Laboratory Karlsruhe (TLK), Institute for Astroparticle Physics (IAP), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76021 Karlsruhe, Germany"}]},{"given":"Genrich","family":"Zeller","sequence":"additional","affiliation":[{"name":"Tritium Laboratory Karlsruhe (TLK), Institute for Astroparticle Physics (IAP), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76021 Karlsruhe, Germany"}]}],"member":"1968","published-online":{"date-parts":[[2021,9,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"143","DOI":"10.13182\/FST08-A1786","article-title":"A decade of tritium technology development and operation at the Tritium Laboratory Karlsruhe","volume":"54","author":"Besserer","year":"2008","journal-title":"Fusion Sci. 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