{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,3]],"date-time":"2026-04-03T03:45:12Z","timestamp":1775187912900,"version":"3.50.1"},"reference-count":36,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2020,4,16]],"date-time":"2020-04-16T00:00:00Z","timestamp":1586995200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","award":["UIDB\/00511\/2020"],"award-info":[{"award-number":["UIDB\/00511\/2020"]}]},{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","award":["UIDB\/50020\/2020"],"award-info":[{"award-number":["UIDB\/50020\/2020"]}]},{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","award":["PTDC\/BTA-BTA\/31736\/2017 - POCI-01-0145-FEDER-031736"],"award-info":[{"award-number":["PTDC\/BTA-BTA\/31736\/2017 - POCI-01-0145-FEDER-031736"]}]},{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","award":["CEECIND\/01317\/2017"],"award-info":[{"award-number":["CEECIND\/01317\/2017"]}]},{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","award":["IF\/01341\/2015"],"award-info":[{"award-number":["IF\/01341\/2015"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Energies"],"abstract":"<jats:p>Microalgae can be a future source of biomass with a wide range of applications, including its use to solve current environmental issues. One of the main variables for microalgal cultivation is the light supply: (i) its intensity that often does not present a uniform spatial distribution inside the culture; (ii) photoperiod; and (iii) spectrum. Therefore, this study aims to evaluate the growth of the microalgae Chlorella vulgaris in a tubular photobioreactor with compound parabolic collectors (CPCs) under outdoor conditions. The effect of ultraviolet and visible radiation on biomass productivity and nutrients (nitrogen and phosphorus) uptake was assessed. The maximum biomass productivity was (5 \u00b1 1) \u00d7 10\u22123 g\u00b7L\u22121\u00b7h\u22121, and the specific growth rates ranged from (1.1 \u00b1 0.3) \u00d7 10\u22122 to (2.0 \u00b1 0.6) \u00d7 10\u22122 h\u22121. Regarding nutrient uptake, initial removal rates of (0.9 \u00b1 0.4) mg N\u00b7L\u22121\u00b7h\u22121 for nitrogen and (0.17 \u00b1 0.04) mg P\u00b7L\u22121\u00b7h\u22121 for phosphorus were reached. These values increased with visible and ultraviolet irradiance until certain values (143 WVIS\u00b7m\u22122 and 9 WUV\u00b7m\u22122 for biomass productivity; 101 WVIS\u00b7m\u22122 and 6 WUV\u00b7m\u22122 for nutrient removal) and then decreased for higher ones due to the photoinhibition phenomenon. Therefore, the application of CPCs to photobioreactors (PBRs) may be beneficial for microalgal culture in countries with higher latitude (with lower solar irradiance levels).<\/jats:p>","DOI":"10.3390\/en13081962","type":"journal-article","created":{"date-parts":[[2020,4,16]],"date-time":"2020-04-16T13:01:39Z","timestamp":1587042099000},"page":"1962","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Outdoor Cultivation of the Microalga Chlorella vulgaris in a New Photobioreactor Configuration: The Effect of Ultraviolet and Visible Radiation"],"prefix":"10.3390","volume":"13","author":[{"given":"Alcinda P.","family":"Lopes","sequence":"first","affiliation":[{"name":"LEPABE\u2014Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"},{"name":"Laboratory of Separation and Reaction Engineering\u2014Laboratory of Catalysis and Materials (LSRE-LCM), Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]},{"given":"Francisca M.","family":"Santos","sequence":"additional","affiliation":[{"name":"LEPABE\u2014Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"},{"name":"Laboratory of Separation and Reaction Engineering\u2014Laboratory of Catalysis and Materials (LSRE-LCM), Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]},{"given":"T\u00e2nia F. C. V.","family":"Silva","sequence":"additional","affiliation":[{"name":"Laboratory of Separation and Reaction Engineering\u2014Laboratory of Catalysis and Materials (LSRE-LCM), Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]},{"given":"V\u00edtor J. P.","family":"Vilar","sequence":"additional","affiliation":[{"name":"Laboratory of Separation and Reaction Engineering\u2014Laboratory of Catalysis and Materials (LSRE-LCM), Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2738-5102","authenticated-orcid":false,"given":"Jos\u00e9 C. M.","family":"Pires","sequence":"additional","affiliation":[{"name":"LEPABE\u2014Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2020,4,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Pereira, S.E.L., Goncalves, A.L., Moreira, F.C., Silva, T.F.C.V., Vilar, V.J.P., and Pires, J.C.M. (2016). Nitrogen removal from landfill leachate by microalgae. Int. J. Mol. Sci., 17.","DOI":"10.3390\/ijms17111926"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"3043","DOI":"10.1016\/j.rser.2012.02.055","article-title":"Carbon dioxide capture from flue gases using microalgae: Engineering aspects and biorefinery concept","volume":"16","author":"Pires","year":"2012","journal-title":"Renew. Sust. 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