{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,13]],"date-time":"2026-08-13T13:34:11Z","timestamp":1786628051423,"version":"build-2736575974"},"reference-count":33,"publisher":"American Chemical Society (ACS)","issue":"8","license":[{"start":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T00:00:00Z","timestamp":1785369600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100008421","name":"Electric Power Research Institute","doi-asserted-by":"publisher","award":["1-11019601-01"],"award-info":[{"award-number":["1-11019601-01"]}],"id":[{"id":"10.13039\/100008421","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100019237","name":"University Network of Excellence in Nuclear Engineering","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100019237","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000038","name":"Natural Sciences and Engineering Research Council of Canada","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100000038","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,8,13]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Ionization constants, Ka,H, for N,N-diethylhydroxylamine (DEHA) have been measured under hydrothermal conditions, from 25 to 250 \u00b0C at 15 MPa, using the thermally stable colorimetric pH indicator acridine. The measurements were carried out by UV\u2013visible spectroscopy using a high-temperature, high-pressure titanium flow cell with sapphire windows. The use of flow minimized the effects of thermal decomposition because the data could be collected rapidly with short equilibration times. NMR and Raman spectroscopic analysis of the quenched experimental solutions from 250 \u00b0C showed that the extent of DEHA decomposition in the experimental solution was minimal at the highest temperature studied. These are the first experimental values for the ionization constant of DEHA above 25 \u00b0C that have been reported. The experimental values of pKa,H for DEHA were fitted using the simplified form of the extended van\u2019t Hoff equation for an isocoulombic reaction and with Mesmer\u2019s \u201cDensity\u201d model to generate thermochemical parameters suitable for the EPRI MULTEQ chemical equilibrium model and other similar software used to model water chemistry in nuclear reactor secondary coolant systems and in fossil steam generating systems.<\/jats:p>","DOI":"10.1021\/acs.jced.6c00121","type":"journal-article","created":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T13:21:03Z","timestamp":1785849663000},"page":"3372-3380","source":"Crossref","is-referenced-by-count":0,"title":["Experimental Determination\nof the Ionization Constant\nof\n                    <i>N<\/i>\n                    ,\n                    <i>N<\/i>\n                    -diethylhydroxylamine\n(DEHA) from 25 to 250 \u00b0C at 15 MPa"],"prefix":"10.1021","volume":"71","author":[{"given":"Sreedhanya","family":"Swaroop","sequence":"first","affiliation":[{"name":"University of Guelph , , 50 Stone Rd. E ., , ,","place":["Guelph, Ontario, Canada, N1G 2W1"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Swaroop","family":"Sasidharanpillai","sequence":"additional","affiliation":[{"name":"University of Guelph , , 50 Stone Rd. E ., , ,","place":["Guelph, Ontario, Canada, N1G 2W1"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9722-9180","authenticated-orcid":true,"given":"Peter R.","family":"Tremaine","sequence":"additional","affiliation":[{"name":"University of Guelph , , 50 Stone Rd. E ., , ,","place":["Guelph, Ontario, Canada, N1G 2W1"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"316","published-online":{"date-parts":[[2026,7,30]]},"reference":[{"key":"2026081308091050300_cit1","first-page":"341","article-title":"Chemistry of steam cycle solutions: Principles","volume-title":"The ASME Handbook on Water Technology for Thermal Power Systems","author":"Lindsay Jr","year":"1989"},{"key":"2026081308091050300_cit2","first-page":"1371","article-title":"Management\nof Cycle Chemistry","volume-title":"The ASME Handbook on\nWater Technology for Thermal Power Systems.","author":"Grabowski","year":"1989"},{"key":"2026081308091050300_cit3","unstructured":"Pressurized Water Reactor\nSecondary Water Chemistry Guidelines-Revision\n8\n          Electric Power Research Institute: Palo Alto, CA; 20173002010645."},{"key":"2026081308091050300_cit4","unstructured":"Marks, C.\n          \n          Steam Generator Management\nProgram: Effects of Different pH Control Agents on Pressurized Water\nReactor Plant Systems and Components\n          Electric\nPower Research Institute: Palo Alto,\nCA; 20091019042."},{"key":"2026081308091050300_cit5","unstructured":"Miller, A. 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