Simptomatologia i microorganismes associats a la necrosi bruna apical de la noguera (Juglans regia)

La Necrosi Apical Bruna (BAN, brown apical necrosis, segons les sigles en anglès) Es va detectar per primer cop l’any 1997 a Extremadura degut a la severa caiguda de fruits. Avui dia la malaltia és present a quasi totes les zones productores de la mediterrània. Els símptomes difereixen dels provocats per Xanthomonas arboricola pv. juglandis i Gnomonia leptsostyla.. S’observa que els fruits afectats presenten una taca bruna a la zona apical i necrosi dels teixits interiors. El grup de Patologia Vegetal de la Universitat de Girona participa i dirigeix la tasca sobre l’etiologia de la BAN dins la xarxa europea d’investigació en bacteris patògens de fruiters ,COST873. Hi ha una certa controvèrsia en la definició dels símptomes i agents causals. Tots els grups coincideixen en afirmar que es tracta d’una malaltia complexa amb diferents organismes implicats

Development of a decision support system for the integrated control of membrane bioreactors

The work presented in this PhD thesis includes various partial studies aimed at developing a decision support system for membrane bioreactor integrated control. The decision support systems (DSS) have as a main goal to facilitate the operation of complex processes due to the multiple variables that are processed. For this reason, the research used has focused on aspects related to nutrient removal, and on the development of indicators or sensors capable of facilitating, automating and controlling the filtration process in an integrated way with the biological processes that taking place. Work has also been done on the design, development, implementation and validation of tools based on the knowledge made available by the automatic control and the supervision of the MBRs

Development of an air-scour control system for membrane bioreactors

The thesis involves the development and implementation of a new and robust control system based on permeability trends but at the same time capable of reducing aeration proportionally to permeate flux. Permeability was made a key parameter for directly comparing temporary changes in membrane performance. Transmembrane pressure and flux were gathered every 10 seconds and permeability values were automatically calculated; different mathematical algorithms were applied for the signal filtering of on-line data. Short term and long term permeability trends were compared once a day, and a control action was applied proportionally to the short term/long term permeability ratio without exceeding the aeration flow recommended by the membrane suppliers.