{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,12]],"date-time":"2026-05-12T00:20:43Z","timestamp":1778545243863,"version":"3.51.4"},"reference-count":34,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2019,2,12]],"date-time":"2019-02-12T00:00:00Z","timestamp":1549929600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Membrane distillation (MD) has recently gained considerable attention as a valid process for the production of fresh-water due to its ability to exploit low grade waste heat for operation and to ensure a nearly feed concentration-independent production of high-purity distillate. Limitations have been related to polarization phenomena negatively affecting the thermal efficiency of the process and, as a consequence, its productivity. Several theoretical models have been developed to predict the impact of the operating conditions of the process on the thermal polarization, but there is a lack of experimental validation. In this study, electrospun nanofiber membranes (ENMs) made of Poly(vinylidene fluoride) (PVDF) and doped with (1, 10-phenanthroline) ruthenium (II) Ru(phen)3 were tested at different operating conditions (i.e., temperature and velocity of the feed) in direct contact membrane distillation (DCMD). The temperature sensitive luminophore, Ru(phen)3, allowed the on-line and non-invasive mapping of the temperature at the membrane surface during the process and the experimental evaluation of the effect of the temperature and velocity of the feed on the thermal polarization.<\/jats:p>","DOI":"10.3390\/molecules24030638","type":"journal-article","created":{"date-parts":[[2019,2,13]],"date-time":"2019-02-13T02:49:44Z","timestamp":1550026184000},"page":"638","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":39,"title":["Experimental Evaluation of the Thermal Polarization in Direct Contact Membrane Distillation Using Electrospun Nanofiber Membranes Doped With Molecular Probes"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7687-0780","authenticated-orcid":false,"given":"Sergio","family":"Santoro","sequence":"first","affiliation":[{"name":"Institute on Membrane Technology (ITM-CNR), via P. Bucci 17\/C, 87036 Rende (CS), Italy"},{"name":"Institute of Nanoscience of Aragon (INA) and Department of Chemical, Engineering and Environmental Technology, University of Zaragoza, C\/Mariano Esquillor, s\/n, I+D+i Building, 50018 Zaragoza, Spain"},{"name":"LAQV, REQUIMTE, Departamento de Qu\u00edmica, Faculdade de Ci\u00eancias e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal"}]},{"given":"Ivan","family":"Vidorreta","sequence":"additional","affiliation":[{"name":"Institute of Nanoscience of Aragon (INA) and Department of Chemical, Engineering and Environmental Technology, University of Zaragoza, C\/Mariano Esquillor, s\/n, I+D+i Building, 50018 Zaragoza, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7032-3436","authenticated-orcid":false,"given":"Isabel","family":"Coelhoso","sequence":"additional","affiliation":[{"name":"LAQV, REQUIMTE, Departamento de Qu\u00edmica, Faculdade de Ci\u00eancias e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0528-1967","authenticated-orcid":false,"given":"Joao Carlos","family":"Lima","sequence":"additional","affiliation":[{"name":"LAQV, REQUIMTE, Departamento de Qu\u00edmica, Faculdade de Ci\u00eancias e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal"}]},{"given":"Giovanni","family":"Desiderio","sequence":"additional","affiliation":[{"name":"Istituto di Nanotecnologia (CNR - NANOTEC), Via P. Bucci 31c, 87036 Rende (Cs), Italy"}]},{"given":"Giuseppe","family":"Lombardo","sequence":"additional","affiliation":[{"name":"Istituto per i Processi Chimico-Fisici, CNR-IPCF, Viale F. Stagno D\u2019Alcontres 37, 98158 Messina, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1092-5368","authenticated-orcid":false,"given":"Enrico","family":"Drioli","sequence":"additional","affiliation":[{"name":"Institute on Membrane Technology (ITM-CNR), via P. Bucci 17\/C, 87036 Rende (CS), Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4758-9380","authenticated-orcid":false,"given":"Reyes","family":"Mallada","sequence":"additional","affiliation":[{"name":"Institute of Nanoscience of Aragon (INA) and Department of Chemical, Engineering and Environmental Technology, University of Zaragoza, C\/Mariano Esquillor, s\/n, I+D+i Building, 50018 Zaragoza, Spain"}]},{"given":"Joao","family":"Crespo","sequence":"additional","affiliation":[{"name":"LAQV, REQUIMTE, Departamento de Qu\u00edmica, Faculdade de Ci\u00eancias e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal"}]},{"given":"Alessandra","family":"Criscuoli","sequence":"additional","affiliation":[{"name":"Institute on Membrane Technology (ITM-CNR), via P. Bucci 17\/C, 87036 Rende (CS), Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3347-0506","authenticated-orcid":false,"given":"Alberto","family":"Figoli","sequence":"additional","affiliation":[{"name":"Institute on Membrane Technology (ITM-CNR), via P. Bucci 17\/C, 87036 Rende (CS), Italy"}]}],"member":"1968","published-online":{"date-parts":[[2019,2,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"301","DOI":"10.1038\/nature06599","article-title":"Science and technology for water purification in the coming decades","volume":"452","author":"Shannon","year":"2008","journal-title":"Nature"},{"key":"ref_2","first-page":"1","article-title":"Materials and membrane technologies for water and energy sustainability","volume":"7","author":"Le","year":"2016","journal-title":"Sustain. Mater. Technol."},{"key":"ref_3","first-page":"1","article-title":"Water desalination: The role of RO and MSF","volume":"6","author":"Singh","year":"2013","journal-title":"J. Environ. 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