280 results on '"Osmose"'
Search Results
2. Zur kolloidalen Natur von AKR‐Produkten.
- Author
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Giebson, Colin and Ludwig, Horst‐Michael
- Subjects
CONCRETE - Abstract
Kurzfassung: Von den Produkten einer Alkali‐Kieselsäure‐Reaktion (AKR) wird angenommen, dass sie Wasser aufnehmen und sich infolgedessen ein Quelldruck in Gesteinskörnern und im Zementstein aufbaut, der Dehnungen verursacht und schließlich zur Rissbildung im Beton führt. Neuere Untersuchungen haben jedoch gezeigt, dass AKR‐Produkte oft eine kristalline Struktur haben und weniger Wasser aufnehmen als erwartet. Darüber hinaus sind gemessene Quelldrücke oft überraschend gering. Offensichtlich ist die Natur der AKR‐Produkte noch nicht in ausreichendem Umfang verstanden worden. Ergebnisse eigener Untersuchungen zeigten, dass AKR‐Produkte als kolloidale Systeme betrachtet werden können. Um zu klären, ob und inwieweit AKR‐Produkte kolloidale Eigenschaften aufweisen, wurden 10 AKR‐Produkte mit unterschiedlicher Zusammensetzung und unterschiedlichem Wassergehalt bei zwei Temperaturen (40 und 60 °C) synthetisiert. Die AKR‐Produkte wurden über einen Zeitraum von 1,5 Jahren unter anderem mittels der Rasterelektronenmikroskopie, der Nanopartikelanalyse sowie mittels eines Osmosezellenversuchs untersucht. Die Ergebnisse zeigen insbesondere, dass AKR‐Produkte Partikel kolloidaler Größe (50‐600 nm) enthalten. Dadurch kann es im Beton zum DONNAN‐Effekt kommen, der zur Osmose führt und damit eine Erklärung für den AKR‐Quellvorgang liefert. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
3. Touching, Licking, Tasting: Performing Multisensory Spatial Perception Through Extended‐Reality Models.
- Author
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Strunden, Paula
- Abstract
There has been much written speculation about leaving the body on entering fully virtual space. However, it is clear that the only reason we can experience virtual reality is precisely because we are embodied. Transdisciplinary researcher and architectural artist Paula Strunden works at the intersection of the real and the virtual, exploiting our body's important conduits for complete sensory and visceral experience of augmented space. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
4. Novel technologies combined with osmotic dehydration for application in the conservation of fruits: an overview.
- Author
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de Sousa Pinto, Barbara, Campos de Melo, Ariane Carla, da Costa Junior, Esly Ferreira, and Souza da Costa, Andréa Oliveira
- Subjects
- *
DRIED fruit , *MASS transfer , *FRUIT , *GAMMA rays , *CONSERVATION of mass , *HYPERTONIC solutions - Abstract
Osmotic dehydration (OD) is a technique used for the partial removal of water from foodstuff, including fruit and vegetables, with the aim of producing a desiccated product. The process involves placing the material in a hypertonic solution for several hours and allowing water to move from the cell compartment into the solution by osmosis. OD is influenced by various factors such as the concentration and composition of the osmotic solution, the solution temperature, the type of agitation and the time of exposure, as well as the size, shape and compactness of the food material. The main advantages of OD over conventional drying processes are the superior quality of the dried products and the minimization of shrinkage. In recent years, research effort has focused on the combination of OD with other technologies, such as ultrasound, cryogenic freezing with liquid nitrogen, pulsed electric field, gamma radiation and high hydrostatic pressure. The application of these methods prior to or concomitant with OD accelerates mass transfer and reduces the drying rate of fruit and vegetables by increasing the permeability of cell membranes. In this manner, combined processes tend to be more efficient and economical in comparison with conventional OD because they reduce operating times and; consequently, energy consumption. In addition, the dried products generated by such coupled processes typically exhibit improved nutritional and physicochemical characteristics. This review summarizes the basic principles and applications of OD in combination with other methods, with particular emphasis on the production of dried fruits. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
5. Exploring balanced harvest as a potential strategy for highly exploited multispecies fisheries.
- Author
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Sun, Runlong, Sun, Peng, Fu, Caihong, Liu, Guankui, Liang, Zhenlin, Shin, Yunne-Jai, Barrier, Nicolas, and Tian, Yongjun
- Subjects
- *
FISHERIES , *FISHERY management , *FISH mortality , *FUNCTIONAL groups , *DEATH rate , *BIOMASS ,DEVELOPING countries - Abstract
Balanced harvest (BH) proposes moderate fishing mortality rates across all species or sizes in proportion to productivity, serving as a possible strategy for ecosystem-based fisheries management. Fishing patterns in some developing countries (e.g. China, the largest producer of seafood) closely resemble BH, where catches have been highly diversified by unselective gears due to market demand for almost all species. In this study, we employed an OSMOSE ecosystem model developed for the Yellow Sea in China to investigate the potential occurrences and advantages of BH in this region with highly exploited multispecies fisheries. Simulations were carried out under four types of fishing scenarios, where various levels of fishing mortality rates for all species or specific functional groups were implemented. Results indicated that the occurrences of BH depended on fishing pressure and targeted functional groups, and that size-level BH was significantly correlated with biomass and yield for most species. In particular, varying fishing pressure for certain functional groups resulted in BH, which produced a high yield for specific species and ensured their biomass sustainability. We concluded that the benefits of BH could be potentially achieved by adjusting fishing pressure for certain functional groups based on the existing fishing pattern in over-exploited ecosystems. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
6. Diving deeper: Mesopelagic fish biomass estimates comparison using two different models
- Author
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Mariana Hill Cruz, Iris Kriest, and Julia Getzlaff
- Subjects
mesopelagic fish ,food-web model ,OSMOSE ,twilight zone ,multispecies model ,life cycle ,Science ,General. Including nature conservation, geographical distribution ,QH1-199.5 - Abstract
A growing population on a planet with limited resources demands finding new sources of protein. Hence, fisheries are turning their perspectives towards mesopelagic fish, which have, so far, remained relatively unexploited and poorly studied. Large uncertainties are associated with regards to their biomass, turn-over rates, susceptibility to environmental forcing and ecological and biogeochemical role. Models are useful to disentangle sources of uncertainties and to understand the impact of different processes on the biomass. In this study, we employed two food-web models – OSMOSE and the model by Anderson et al. (2019, or A2019) – coupled to a regional physical–biogeochemical model to simulate mesopelagic fish in the Eastern Tropical South Pacific ocean. The model by A2019 produced the largest biomass estimate, 26 to 130% higher than OSMOSE depending on the mortality parameters used. However, OSMOSE was calibrated to match observations in the coastal region off Peru and its temporal variability is affected by an explicit life cycle and food web. In contrast, the model by A2019 is more convenient to perform uncertainty analysis and it can be easily coupled to a biogeochemical model to estimate mesopelagic fish biomass. However, it is based on a flow analysis that had been previously applied to estimate global biomass of mesopelagic fish but has never been calibrated for the Eastern Tropical South Pacific. Furthermore, it assumes a steady-state in the energy transfer between primary production and mesopelagic fish, which may be an oversimplification for this highly dynamic system. OSMOSE is convenient to understand the interactions of the ecosystem and how including different life stages affects the model response. The combined strengths of both models allow us to study mesopelagic fish from a holistic perspective, taking into account energy fluxes and biomass uncertainties based on primary production, as well as complex ecological interactions.
- Published
- 2023
- Full Text
- View/download PDF
7. Detection of fishing pressure using ecological network indicators derived from ecosystem models
- Author
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Maysa Ito, Ghassen Halouani, Pierre Cresson, Carolina Giraldo, and Raphaël Girardin
- Subjects
OSMOSE ,Atlantis ,Ecological network analysis ,Network indicators ,Fishery ,Ecosystem model ,Ecology ,QH540-549.5 - Abstract
Marine ecosystems are exposed to multiple stressors, mainly fisheries that, whenever mismanaged, may cause irreversible damages to whole food webs. Ecosystem models have been applied to forecast fisheries impact on fish stocks and marine food webs. These impacts have been studied through the use of multiple indicators that help to understand ecosystem responses to stressors. This study focused on a category of ecological indicators derived from the network theory to quantify energy flows inside the food web. These indicators were computed using two ecosystem models applied to the Eastern English Channel (i.e. Atlantis and OSMOSE). This work aimed at investigating how several ecological network indicators respond to different levels of fishing pressure and evaluating their robustness to model structure and fishing strategies. We applied a gradient of fishing mortality using two ecosystem models and carried out ecological network analysis to obtain network-derived indicators. The results revealed that the indicators response is highly driven by the food web structure, although the model assumptions buffered some results. The indicators computed from OSMOSE outputs were more sensitive to changes in fishing pressure than those from Atlantis. However, once the food web from Atlantis was simplified to mimic the structure of OSMOSE model, the indicators of the modified Atlantis became more sensitive to the intensity of fishing pressure. The indicators related to amount of energy flow and to the organization of the flows in the food web were sensitive to the increase of fishing mortality for all fishing strategies. These indicators suggested that increasing fishing mortality jeopardizes the amount of energy mobilized by the food webs and simplifies the ecological interactions, which has implications for the resilience of marine ecosystems. The study shed light on the trophic networks structure and functioning of the ecosystems whenever exposed to disturbances. Furthermore, these indicators might be adequate for whole ecosystem assessments of health and contribute to ecosystem management.
- Published
- 2023
- Full Text
- View/download PDF
8. Educação antirracista no ensino de química: Sobre representatividade e osmose.
- Author
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Batista Alvino, Antônio César, Barcelos Moreira, Marilene, Rodrigues Camargo, Marysson Jonas, and Canavarro Benite, Anna Maria
- Subjects
RACE ,HIGH school students ,PARTICIPANT observation ,LEGAL education ,OSMOSIS - Abstract
Copyright of Revista Electrónica de Enseñanza de las Ciencias is the property of Revista Electronica de Ensenanza de las Ciencias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2022
9. Percepciones de los estudiantes de octavo grado acerca de la ósmosis en el colegio Liceo Integral los Alisos ubicado en el municipio de Soacha-Cundinamarca, Colombia.
- Author
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Rey Romero, Jeferson Stip and Gómez Villamil, Laura Valentina
- Subjects
EDUCATIONAL standards ,CONCEPT learning ,OSMOSIS ,HUMAN rights ,EVERYDAY life - Abstract
Copyright of Bio-grafía. Escritos Sobre la Biología y su Enseñanza is the property of Universidad Pedaggica Nacional and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2022
10. Current Trends and Future Developments on (Bio-) Membranes : Reverse and Forward Osmosis: Principles, Applications, Advances
- Author
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Angelo Basile, Alfredo Cassano, Navin Kumar Rastogi, Angelo Basile, Alfredo Cassano, and Navin Kumar Rastogi
- Subjects
- Membranes (Technology), Osmosis, Membranes (Technologie), Osmose
- Abstract
Current Trends and Future Developments on (Bio-) Membranes: Reverse and Forward Osmosis: Principles, Applications, Advances covers the important aspects of RO, FO and their combination in integrated systems, along with their specific and well-established applications. The book offers an overview of recent developments in the field of forward and reverse osmosis and their applications in water desalination, wastewater treatment, power generation and food processing. General principles, membrane module developments, membrane fouling, modeling, simulation and optimization of both technologies are also covered. The book's ultimate goal is to support the scientific community, professionals and enterprises that aspire to develop new applications. - Provides an overview of the advances made in combining reverse osmosis membrane technology and the corresponding forward osmosis - Provides a comprehensive review of advanced research on membrane processes for water desalination, wastewater treatments, etc. - Addresses key issues in process intensification and extraction of energy from renewable sources - Identifies further research needs for the practical implementation of these two membrane technologies
- Published
- 2019
11. DESSALINIZAÇÃO DE ÁGUA SALOBRA POR OSMOSE REVERSA: UMA REVISÃO DE LITERATURA.
- Author
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ARAUJO, GÉSSICA CONRADO, ROSA, THAÍS DE SOUZA, and OLIVEIRA, TIAGO MARCEL
- Subjects
SEPARATION (Technology) ,MEMBRANE separation ,ARTIFICIAL membranes ,BRACKISH waters ,SALINE water conversion ,REVERSE osmosis - Abstract
Copyright of Journal of Exact Sciences is the property of Master Editora and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2021
12. Evaluating Impacts of Trophic Interactions on the Effectiveness of Single-Species Fisheries Management
- Author
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Lei Xing, Yong Chen, Bai Li, Kisei R. Tanaka, Robert Boenish, Yiping Ren, and Binduo Xu
- Subjects
OSMOSE ,single-species fisheries management ,prey-predator process ,food competition ,Jiaozhou Bay ,Science ,General. Including nature conservation, geographical distribution ,QH1-199.5 - Abstract
Single-species fisheries management (SSFM) is applied to many fisheries ecosystems around the world. The associated ecological impacts are usually not well understood due to the lack of considering trophic interactions among species in the ecosystem. This impedes the implementation of SSFM in an ecosystem context and reduces our ability to understand the possible ecological impacts of fishing activities. This study focuses on two economically important species in the Jiaozhou Bay, China: the short-lived, fast-growing, and relatively abundant Japanese mantis shrimp (Oratosquilla oratoria) and the long-lived, slow-growing, and less abundant Korean rockfish (Sebastes schlegelii). We evaluated how varying trophic interactions influenced O. oratoria and S. schlegelii (i.e., target-species) who were managed under constant fishing pressure. The increase of fishing pressure to other species (i.e., non-target species) was beneficial to O. oratoria and S. schlegelii. O. oratoria was more sensitive to the decrease of fishing pressure to other species. The predation mortality of age-0 O. oratoria increased with the increased fishing pressure to other species. The predation mortality of age-1 O. oratoria and age-0 S. schlegelii had negative relationships with the fishing pressure to other species. Age-1 S. schlegelii seemed not to be sensitive to the changes in trophic interactions. The predation mortality of O. oratoria and S. schlegelii had bigger changes than the starvation mortality after fishing changed. It suggested the prey-predator relationship had a bigger impact than the food competition. The increase of high-trophic-level fish Johnius belangerii fishery positively impacted O. oratoria, but negatively impacted S. schlegelii. S. schlegelii was more sensitive to the changes of the low-trophic-level fish Pholis fangi fishery. Given the complex dynamics of ecosystems, this study highlights the importance of species-specific responses of fishes to shifting trophic interactions in fisheries management.
- Published
- 2021
- Full Text
- View/download PDF
13. Osmotische Wirkung von Kochsalz: Ein Schülerexperiment zur Bestimmung der Zellsaftkonzentration bei verschiedenen Gemüsearten
- Author
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Fabian Schumacher, Gabriele Beyer-Sehlmeyer, Stefanie Henrich, Sabrina Polte, Andreas Stockey, and Matthias Wilde
- Subjects
Experimentieren ,Osmose ,Unterrichtskonzept ,Scientific Inquiry ,Mathematisierung ,Education - Abstract
Salze sind für Lebewesen lebenswichtig. In hohen Konzentrationen wirken sie aber u.U. toxisch. In vorhergehenden Unterrichtseinheiten haben sich die Schüler*innen bereits mit dem Aufbau und der Struktur von tierischen und pflanzlichen Zellen beschäftigt. In der vorliegenden Einheit wird den Schüler*innen die Gelegenheit gegeben, die Wirkung von Salzen auf Zellen zu verstehen. Eine Messung der Gewichtsveränderung, verursacht durch osmotische Vorgänge in den Zellen, ermöglicht die Bestimmung und den Vergleich der Zellsaft-Konzentration von Gemüsearten.
- Published
- 2020
- Full Text
- View/download PDF
14. Lösungswärme energetisch betrachtet: Ein Schülerexperiment zur Bestimmung der konzentrationsabhängigen Lösungsenthalpie beim Lösen verschiedener Salze
- Author
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Cornelia Stiller, Gabriele Beyer-Sehlmeyer, Gudrun Friedrich, Andreas Stockey, and Tobias Allmers
- Subjects
Experimentieren ,Unterrichtskonzept ,Osmose ,Lösungsenthalpie ,Scientific Inquiry ,Education - Abstract
Im folgenden Beitrag wird ein Schülerexperiment zur experimentellen Bestimmung der Temperaturänderung beim Lösen von Salzen vorgestellt. Im Rahmen des Gesamtkonzeptes des Kurses haben sich die Schüler*innen davor mit der Dichte von Salzlösungen beschäftigt. Der für diese Unterrichtseinheit wichtige Energiebegriff wurde bereits in der Unterrichtseinheit zur Energieerhaltung am Beispiel des Fadenpendels eingeführt und wird hier in einem anderen Kontext aufgegriffen. Anhand des Experiments werden die energetischen Vorgänge beim Lösen eines Salzes erarbeitet.
- Published
- 2020
- Full Text
- View/download PDF
15. Schüler*innen werten selbstständig ein Experiment zur Bestimmung der Zellsaftkonzentration (Osmose) aus
- Author
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Holger Bekel-Kastrup, Philipp Hamers, Svea Isabel Kleinert, Darius Haunhorst, and Matthias Wilde
- Subjects
Binnendifferenzierung ,Biologieunterricht ,Naturwissenschaftlicher Unterricht ,gestufte Lernhilfen ,Osmose ,Zellsaftkonzentration ,Education (General) ,L7-991 - Abstract
In dem Forschungsprojekt „Bielefelder Binnendifferenzierung in den MINT-Fächern“ (BiBi-MINT) am Oberstufen-Kolleg Bielefeld zur Verzahnung von Mathematikunterricht und Naturwissenschaftsunterricht mit gleichzeitigem Fokus auf die Binnendifferenzierung sind unter anderem gestufte Lernhilfen zur Auswertung eines Experimentes zur Bestimmung der Zellsaftkonzentration entwickelt, angewendet und evaluiert worden. Sie sind dazu geeignet, Schüler*innen eigenverantwortlich die Auswertung und Interpretation des Experimentes durchführen zu lassen. Das Untersuchungsprinzip des Experimentes ist das Bestimmen der Masse von Gemüsestreifen vor und nach dem Einlegen in verschieden konzentrierten NaCl-Lösungen. Die Lernhilfen beinhalten dabei sowohl eine wiederholende Hinführung zur Bestimmung der relativen Massendifferenz als auch eine mathematische Auswertung und Bestimmung der Zellsaftkonzentration. Zur Interpretation werden Inhalte der biologischen Unterrichtsreihe zur Osmose vermittelt bzw. wiederholend bearbeitet.
- Published
- 2020
- Full Text
- View/download PDF
16. Evaluating impacts of pulse fishing on the effectiveness of seasonal closure.
- Author
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Xing, Lei, Chen, Yong, Zhang, Chongliang, Li, Bai, Shin, Yunne-Jai, and Ren, Yiping
- Abstract
Seasonal fishing closures are often used in fisheries management to conserve overfished stocks. As one of the unintended consequences, fishermen often contend for maximizing catches immediately after reopening fisheries. The resultant large catch landings in a short time period (i.e., pulse fishing) may undermine the benefit of closure. We implemented an end-to-end model OSMOSE-JZB (Object-oriented Simulator of Marine ecOSystem Exploitation OSMOSE) modelling ecosystem in the Jiaozhou Bay located in China to evaluate the impact of pulse fishing on the effectiveness of seasonal closure at levels of fish community, population, and individual. Our study demonstrated that the three-month closure was successful in conserving fish stocks. There were small variations on ecological indicators (i.e., total biomass of the community, mean trophic level of the community, mean trophic level of the catch, and Shannon-Wiener biodiversity index) when pulse fishing occurred. Pulse fishing seemed not to result in a great shift in community structure. Compared to other species, the biomass of two large predatory fishes were more susceptible to pulse fishing. Pulse fishing could change the pressure of predators to fish stocks via food webs, especially for young individuals. Our simulations indicate that we can improve the effectiveness of seasonal closure by managing pulse fishing. Although the results derived in this study may be specific to the target ecosystem, the general approach is applicable to other ecosystems when evaluating fishing impacts. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
17. TONICIDAD: ¿UNA PROPIEDAD DE LAS SOLUCIONES Y/O DE LAS CÉLULAS? APRENDIZAJE SUSTENTABLE DEL TRANSPORTE DE AGUA.
- Author
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Píriz, Nazira, López Larrama, María Noel, Tucci, Jerónimo, Cantero, Joselín, and Mallarini, Virginia
- Abstract
Copyright of Bio-grafía. Escritos Sobre la Biología y su Enseñanza is the property of Universidad Pedaggica Nacional and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2020
18. Ecosystem-based reference points under varying plankton productivity states and fisheries management strategies.
- Author
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Guo, Chuanbo, Fu, Caihong, Forrest, Robyn E, Olsen, Norm, Liu, Huizhu, Verley, Philippe, and Shin, Yunne-Jai
- Subjects
- *
FISHERY management , *SUSTAINABLE fisheries , *PLANKTON , *FISH mortality , *CLIMATE change , *BIOMASS - Abstract
In the context of ecosystem-based fisheries management, which should consider changing and uncertain environmental conditions, the development of ecosystem-based biological reference points (EBRPs) to account for important multi-species (MS) interactions, fishery operations, and climate change, is of paramount importance for sustainable fisheries management. However, EBRPs under varying plankton productivity states and fisheries management strategies are seldom developed, and the ecosystem effects of these changes are still largely unknown. In this study, ecosystem-based F MSY (fishing mortality rate at MSY) values were estimated within an end-to-end ecosystem model (OSMOSE) for three focused fish species (Pacific Herring, Clupea pallasii ; Pacific Cod, Gadus macrocephalus ; Lingcod, Ophiodon elongatus) under three plankton productivity states of differing plankton biomass at high, current, and low levels. In addition, ecosystem effects were compared across different plankton productivity and fisheries management strategies with the latter consisting of two fishery scenarios (i.e. single-species-focused (SS) and MS-focused), various fishing mortality rates, and two harvest policies (with and without harvest control rules, HCRs). Main findings of this study include: (i) plankton productivity change affected the values of ecosystem-based F MSY, which increased as plankton productivity states changed from low to high plankton biomass; (ii) ecosystem-based F MSY for Pacific Herring and Pacific Cod stocks increased when fishery scenarios shifted from SS-focused to MS-focused; (iii) fisheries management incorporating HCR yielded more stable system catch and system biomass; and (iv) high plankton biomass combined with fisheries management using HCR could maintain stable ecosystem production and sustainable fisheries. Based on our findings, we highlight possible adaptive fisheries management strategies in the face of future climate and ocean changes. Overall, EBRPs complement SS stock assessments by incorporating key ecological processes and ecosystem properties, thus providing supporting evidence for better incorporation of ecosystem considerations into scientific advice for sustainable fisheries management. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
19. Siebter Ausflug: Zum Wasser
- Author
-
Neubauer, Dieter and Neubauer, Dieter
- Published
- 2016
- Full Text
- View/download PDF
20. Detection of fishing pressure using ecological network indicators derived from ecosystem models
- Author
-
Ito, Maysa, Halouani, Ghassen, Cresson, Pierre, Giraldo, Carolina, Girardin, Raphael, Ito, Maysa, Halouani, Ghassen, Cresson, Pierre, Giraldo, Carolina, and Girardin, Raphael
- Abstract
Marine ecosystems are exposed to multiple stressors, mainly fisheries that, whenever mismanaged, may cause irreversible damages to whole food webs. Ecosystem models have been applied to forecast fisheries impact on fish stocks and marine food webs. These impacts have been studied through the use of multiple indicators that help to understand ecosystem responses to stressors. This study focused on a category of ecological indicators derived from the network theory to quantify energy flows inside the food web. These indicators were computed using two ecosystem models applied to the Eastern English Channel (i.e. Atlantis and OSMOSE). This work aimed at investigating how several ecological network indicators respond to different levels of fishing pressure and evaluating their robustness to model structure and fishing strategies. We applied a gradient of fishing mortality using two ecosystem models and carried out ecological network analysis to obtain network-derived indicators. The results revealed that the indicators response is highly driven by the food web structure, although the model assumptions buffered some results. The indicators computed from OSMOSE outputs were more sensitive to changes in fishing pressure than those from Atlantis. However, once the food web from Atlantis was simplified to mimic the structure of OSMOSE model, the indicators of the modified Atlantis became more sensitive to the intensity of fishing pressure. The indicators related to amount of energy flow and to the organization of the flows in the food web were sensitive to the increase of fishing mortality for all fishing strategies. These indicators suggested that increasing fishing mortality jeopardizes the amount of energy mobilized by the food webs and simplifies the ecological interactions, which has implications for the resilience of marine ecosystems. The study shed light on the trophic networks structure and functioning of the ecosystems whenever exposed to disturbances. Furthermore
- Published
- 2023
- Full Text
- View/download PDF
21. Exploring balanced harvest as a potential strategy for highly exploited multispecies fisheries
- Author
-
Runlong Sun, Peng Sun, Caihong Fu, Guankui Liu, Zhenlin Liang, Yunne-Jai Shin, Nicolas Barrier, and Yongjun Tian
- Subjects
Ecosystem approach to fisheries ,Ecology ,multispecies fisheries ,ecosystem model ,OSMOSE ,Aquatic Science ,Oceanography ,Balanced harvest ,Ecology, Evolution, Behavior and Systematics - Abstract
Balanced harvest (BH) proposes moderate fishing mortality rates across all species or sizes in proportion to productivity, serving as a possible strategy for ecosystem-based fisheries management. Fishing patterns in some developing countries (e.g. China, the largest producer of seafood) closely resemble BH, where catches have been highly diversified by unselective gears due to market demand for almost all species. In this study, we employed an OSMOSE ecosystem model developed for the Yellow Sea in China to investigate the potential occurrences and advantages of BH in this region with highly exploited multispecies fisheries. Simulations were carried out under four types of fishing scenarios, where various levels of fishing mortality rates for all species or specific functional groups were implemented. Results indicated that the occurrences of BH depended on fishing pressure and targeted functional groups, and that size-level BH was significantly correlated with biomass and yield for most species. In particular, varying fishing pressure for certain functional groups resulted in BH, which produced a high yield for specific species and ensured their biomass sustainability. We concluded that the benefits of BH could be potentially achieved by adjusting fishing pressure for certain functional groups based on the existing fishing pattern in over-exploited ecosystems.
- Published
- 2023
22. An End-to-End Model Reveals Losers and Winners in a Warming Mediterranean Sea
- Author
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Fabien Moullec, Nicolas Barrier, Sabrine Drira, François Guilhaumon, Patrick Marsaleix, Samuel Somot, Caroline Ulses, Laure Velez, and Yunne-Jai Shin
- Subjects
biodiversity scenario ,climate change ,ecosystem model ,end-to-end model ,OSMOSE ,fishing ,Science ,General. Including nature conservation, geographical distribution ,QH1-199.5 - Abstract
The Mediterranean Sea is now recognized as a hotspot of global change, ranking among the fastest warming ocean regions. In order to project future plausible scenarios of marine biodiversity at the scale of the whole Mediterranean basin, the current challenge is to develop an explicit representation of the multispecies spatial dynamics under the combined influence of fishing pressure and climate change. Notwithstanding the advanced state-of-the-art modeling of food webs in the region, no previous studies have projected the consequences of climate change on marine ecosystems in an integrated way, considering changes in ocean dynamics, in phyto- and zoo-plankton productions, shifts in Mediterranean species distributions and their trophic interactions at the whole basin scale. We used an integrated modeling chain including a high-resolution regional climate model, a regional biogeochemistry model and a food web model OSMOSE to project the potential effects of climate change on biomass and catches for a wide array of species in the Mediterranean Sea. We showed that projected climate change would have large consequences for marine biodiversity by the end of the 21st century under a business-as-usual scenario (RCP8.5 with current fishing mortality). The total biomass of high trophic level species (fish and macroinvertebrates) is projected to increase by 5 and 22% while total catch is projected to increase by 0.3 and 7% by 2021–2050 and 2071–2100, respectively. However, these global increases masked strong spatial and inter-species contrasts. The bulk of increase in catch and biomass would be located in the southeastern part of the basin while total catch could decrease by up to 23% in the western part. Winner species would mainly belong to the pelagic group, are thermophilic and/or exotic, of smaller size and of low trophic level while loser species are generally large-sized, some of them of great commercial interest, and could suffer from a spatial mismatch with potential prey subsequent to a contraction or shift of their geographic range. Given the already poor conditions of exploited resources, our results suggest the need for fisheries management to adapt to future changes and to incorporate climate change impacts in future management strategy evaluation.
- Published
- 2019
- Full Text
- View/download PDF
23. Implementation of an end-to-end model of the Gulf of Lions ecosystem (NW Mediterranean Sea). I. Parameterization, calibration and evaluation.
- Author
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Bănaru, Daniela, Diaz, Fréderic, Verley, Philippe, Campbell, Rose, Navarro, Jonathan, Yohia, Christophe, Oliveros-Ramos, Ricardo, Mellon-Duval, Capucine, and Shin, Yunne-Jai
- Subjects
- *
PREY availability , *MARINE parks & reserves , *ENGRAULIS encrasicolus , *FOOD chains , *BLUEFIN tuna - Abstract
Highlights • Spatialized dynamic model linking the coupled model Eco3M-S/SYMPHONIE to OSMOSE. • The model was calibrated and evaluated with satellite, biomass, landings, and trophic data. • Outputs of the end-to-end OSMOSE-GoL model are similar to field and literature data. Abstract An end-to-end model named OSMOSE-GoL has been built for the Gulf of Lions, the main French Mediterranean fishing area. This spatialized dynamic model links the coupled hydrodynamic and biogeochemical model Eco3M-S/SYMPHONIE (LTL – low trophic level model) to OSMOSE (HTL – high trophic level model). It includes 15 compartments of living organisms, five from the LTL model (i.e. nanophytoplankton, microphytoplankton, nanozooplankton, microzooplankton and mesozooplankton) and ten from the HTL model (northern krill, southern shortfin squid, European pilchard, European anchovy, European sprat, Atlantic horse mackerel, Atlantic mackerel, blue whiting, European hake and Atlantic bluefin tuna). With the exception of northern krill and European sprat, all HTL species are commercially exploited and undergo fisheries mortality pressure. The modeled species represent more than 70% of annual catches in this area. This paper presents the parameterization, calibration and evaluation of this model with satellite data for phytoplankton and with biomass, landings, diet and trophic level data for HTL groups. For most species, the diets in output of OSMOSE-GoL are similar to field and literature data in terms of dominant prey groups and species. However, some differences were observed. Various reasons may explain the mismatch between the modeled diet and field data. Benthic prey sometimes observed in the stomach content of the HTL predators were not modeled in OSMOSE-GoL. Field studies were carried out at specific periods and locations, while our data concern the period 2001–2004 and the entire modeled domain. Inter- and intra-annual variations in spatial distribution and density of prey may also explain these differences. The model estimates trophic level values similar to those cited in the literature for all the HTL compartments. These values are also close to the trophic levels estimated by a previous Ecopath model for the same area and period. Even though some improvements are still possible, this model may already be of use to explore fishery or Marine Protected Areas scenarios for socio-ecosystem management issues. [ABSTRACT FROM AUTHOR]
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- 2019
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24. Building bridges between global information systems on marine organisms and ecosystem models.
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Grüss, Arnaud, Palomares, Maria L.D., Poelen, Jorrit H., Barile, Josephine R., Aldemita, Casey D., Ortiz, Shelumiel R., Barrier, Nicolas, Shin, Yunne-Jai, Simons, James, and Pauly, Daniel
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SOFTWARE architecture , *MARINE ecology , *MARINE organisms , *WEB-based user interfaces , *INFORMATION storage & retrieval systems , *USER interfaces , *DATA libraries - Abstract
Highlights • We designed a web application providing parameter values to OSMOSE ecosystem models. • These parameter values are derived from data from FishBase and SeaLifeBase. • Our web application couples a user interface and an application programming interface. • It delivers all the configuration files necessary for running an OSMOSE model. • Other web applications supporting management can be designed with our framework. Abstract To facilitate the wider implementation of ecosystem modeling platforms and, thereby, to help advance ecosystem-based fisheries management (EBFM) worldwide, tools delivering a large quantity of inputs to ecosystem models are needed. We developed a web application providing OSMOSE ecosystem models with values for trophic, growth and reproduction parameters derived from data from two global information systems (FishBase and SeaLifeBase). Our web application guides the user through simple queries to extract information from FishBase and SeaLifeBase data archives, and it delivers all the configuration files necessary for running an OSMOSE model. Here, we present our web application and demonstrate it for the West Florida Shelf ecosystem. Our software architecture can serve as a basis for designing other advanced web applications using FishBase and SeaLifeBase data in support of EBFM. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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25. An end-to-end model to evaluate the sensitivity of ecosystem indicators to track fishing impacts.
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Halouani, Ghassen, Le Loc'h, François, Shin, Yunne-Jai, Velez, Laure, Hattab, Tarek, Romdhane, Mohamed Salah, and Ben Rais Lasram, Frida
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- *
BIOINDICATORS , *FISHING , *FISHERY management , *MARINE ecology - Abstract
Graphical abstract Highlights • An end-to-end model was used to evaluate a set of indicators in the Gulf of Gabes. • Contrasted fishing strategies were simulated to test the performance of indicators. • The indicators were compared based on their sensitivity to fishing pressure. • 3 paradigms defining the desirable properties of an indicator were scrutinized. • The Large Fish Indicators were the most sensitive to track fishing effects. Abstract In order to assist fisheries managers, ecological indicators are needed to evaluate the effects of fishing activities on marine ecosystems and to improve communication of these effects in both public and scientific contexts. Finding appropriate indicators is challenging given the complexity of marine food webs as well as the ecosystem response to fishing pressure. In this study, an end-to-end model developed in the Gulf of Gabes ecosystem (Tunisia) was used to compare the performance of a set of ecosystem indicators in assessing the impact of fishing. This end-to-end model aimed to represent the ecosystem functioning by coupling two existing sub-models, the multispecies individual-based model OSMOSE, representing the dynamics of exploited species and the biogeochemical model Eco3M-Med. The aim of the indicator selection method is to evaluate the sensitivity of a set of ecological indicators regardless the fishing management plan. This method was performed in two major steps. The first step consisted in simulating three simple contrasted fishing strategies in the OSMOSE model exploiting target species (i.e. high trophic level, low trophic level or all species) and then applying a fishing effort multiplier for each fishing strategy to the focus target species. In the second step, three paradigms defining the desirable properties of an ecological indicator have been specified: i/the indicator decreases with increasing fishing pressure, ii/the indicator responds linearly to an increase in fishing pressure and iii/the indicator responds consistently across different fishing strategies. Our results highlighted that the majority of indicators have quite similar performance regarding the trend and the linearity of their responses. However, the size-based indicators seem to be the most robust to track ecosystem effects of fishing when the fishing strategy changes. A focus on size-based indicators showed that Large Fish Indicators (40 cm) derived from demersal or all surveyed species were the most suitable to reflect a change in the status of the Gulf of Gabes ecosystem due to fishing pressure. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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26. Osmose
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Gressner, Axel M., editor and Arndt, Torsten, editor
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- 2019
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27. Novas tecnologias combinadas com desidratação osmótica para aplicação na conservação de frutas: uma revisão
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Barbara de Sousa Pinto, Ariane Carla Campos de Melo, Esly Ferreira da Costa Junior, and Andréa Oliveira Souza da Costa
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transferência de massa ,General Veterinary ,processamento e conservação de frutas ,mass transfer ,desidratação ,osmose ,Animal Science and Zoology ,dehydration ,osmosis ,combined technologies ,tecnologias combinadas ,Agronomy and Crop Science ,fruit processing and conservation - Abstract
Osmotic dehydration (OD) is a technique used for the partial removal of water from foodstuff, including fruit and vegetables, with the aim of producing a desiccated product. The process involves placing the material in a hypertonic solution for several hours and allowing water to move from the cell compartment into the solution by osmosis. OD is influenced by various factors such as the concentration and composition of the osmotic solution, the solution temperature, the type of agitation and the time of exposure, as well as the size, shape and compactness of the food material. The main advantages of OD over conventional drying processes are the superior quality of the dried products and the minimization of shrinkage. In recent years, research effort has focused on the combination of OD with other technologies, such as ultrasound, cryogenic freezing with liquid nitrogen, pulsed electric field, gamma radiation and high hydrostatic pressure. The application of these methods prior to or concomitant with OD accelerates mass transfer and reduces the drying rate of fruit and vegetables by increasing the permeability of cell membranes. In this manner, combined processes tend to be more efficient and economical in comparison with conventional OD because they reduce operating times and; consequently, energy consumption. In addition, the dried products generated by such coupled processes typically exhibit improved nutritional and physicochemical characteristics. This review summarizes the basic principles and applications of OD in combination with other methods, with particular emphasis on the production of dried fruits. RESUMO: A desidratação osmótica (DO) é uma técnica utilizada para remover parcialmente a água dos alimentos, incluindo frutas e vegetais, com vistas a produção de alimentos secos. O processo consiste em colocar o material em uma solução hipertônica por várias horas e deixar a água passar do compartimento celular para a solução por osmose. A DO é influenciada por vários fatores como a concentração e composição da solução osmótica, a temperatura da solução, o tipo de agitação e o tempo de exposição, assim como o tamanho, forma e compactação do material alimentar. As principais vantagens da DO em relação aos processos de secagem convencionais são que ela dá origem a produtos secos de qualidade superior e minimiza o encolhimento. Nos últimos anos, tem-se investigado a combinação da DO com outras tecnologias, tais como ultrassom, congelamento criogênico com nitrogênio líquido, campo elétrico pulsado, radiação gama e alta pressão hidrostática. A aplicação desses métodos antes ou simultaneamente com a DO acelera a transferência de massa e reduz a taxa de secagem de frutas e vegetais através do aumento da permeabilidade das membranas celulares. Assim, os processos combinados tendem a ser mais eficientes e econômicos do que a DO convencional, pois reduzem o tempo de operação e, consequentemente, o consumo de energia. Adicionalmente, os produtos desidratados gerados através de processos associados geralmente apresentam melhores características nutricionais e físico-químicas. Esta revisão sumariza os princípios básicos e aplicações da DO em combinação com outros métodos, com ênfase especial dada à produção de frutas secas.
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- 2022
28. Understanding the drivers of fish variability in an end-to-end model of the Northern Humboldt Current System
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Mariana Hill Cruz, Ivy Frenger, Julia Getzlaff, Iris Kriest, Tianfei Xue, and Yunne-Jai Shin
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Higher trophic levels ,Eastern boundary upwelling system ,physical-biogeochemical model ,Ecological Modeling ,Ecosystem modelling ,End-to-end model ,CROCO ,Northern Humboldt Current System ,Fisheries ,OSMOSE ,Trophic interactions ,BioEBUS - Abstract
Highlights: • Modelled fish biomass was affected by interannual variability in the plankton food. • The effects were small compared with the high variability in observations. • Fish were highly affected by changes in the larval mortality of anchovy. Abstract: The Northern Humboldt Current System is the most productive eastern boundary upwelling system, generating about 10 % of the global fish production, mainly coming from small pelagic fish. It is bottom-up and top-down affected by environmental and anthropogenic variability, such as El-Niño Southern Oscillation and fishing pressure, respectively. The high variability of small pelagic fish in this system, as well as their economic importance, call for a careful management aided by the use of end-to-end models. This type of models represent the ecosystem as a whole, from the physics, through plankton up to fish dynamics. In this study, we utilised an end-to-end model consisting of a physical–biogeochemical model (CROCO-BioEBUS) coupled one-way with an individual-based fish model (OSMOSE). We investigated how time-variability in plankton food production affects fish populations in OSMOSE and contrasted it against the sensitivity of the model to two parameters with high uncertainty: the plankton accessibility to fish and fish larval mortality. Relative interannual variability in the modelled fish is similar to plankton variability. It is, however, small compared with the high variability seen in fish observations in this productive ecosystem. In contrast, changes in larval mortality have a strong effect on anchovies. In OSMOSE, it is a common practice to scale plankton food for fish, accounting for processes that may make part of the total plankton in the water column unavailable. We suggest that this scaling should be done constant across all plankton groups when previous knowledge on the different availabilities is lacking. In addition, end-to-end modelling systems should consider environmental impacts on other biological processes such as larval mortality in order to better capture the interactions between environmental processes, plankton and fish.
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- 2022
29. Understanding the drivers of fish variability in an end-to-end model of the Northern Humboldt Current System
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Hill Cruz, Mariana, Frenger, Ivy, Getzlaff, Julia, Kriest, Iris, Xue, Tianfei, Shin, Yunne-jai, Hill Cruz, Mariana, Frenger, Ivy, Getzlaff, Julia, Kriest, Iris, Xue, Tianfei, and Shin, Yunne-jai
- Abstract
The Northern Humboldt Current System is the most productive eastern boundary upwelling system, generating about 10 % of the global fish production, mainly coming from small pelagic fish. It is bottom-up and top-down affected by environmental and anthropogenic variability, such as El-Niño Southern Oscillation and fishing pressure, respectively. The high variability of small pelagic fish in this system, as well as their economic importance, call for a careful management aided by the use of end-to-end models. This type of models represent the ecosystem as a whole, from the physics, through plankton up to fish dynamics. In this study, we utilised an end-to-end model consisting of a physical–biogeochemical model (CROCO-BioEBUS) coupled one-way with an individual-based fish model (OSMOSE). We investigated how time-variability in plankton food production affects fish populations in OSMOSE and contrasted it against the sensitivity of the model to two parameters with high uncertainty: the plankton accessibility to fish and fish larval mortality. Relative interannual variability in the modelled fish is similar to plankton variability. It is, however, small compared with the high variability seen in fish observations in this productive ecosystem. In contrast, changes in larval mortality have a strong effect on anchovies. In OSMOSE, it is a common practice to scale plankton food for fish, accounting for processes that may make part of the total plankton in the water column unavailable. We suggest that this scaling should be done constant across all plankton groups when previous knowledge on the different availabilities is lacking. In addition, end-to-end modelling systems should consider environmental impacts on other biological processes such as larval mortality in order to better capture the interactions between environmental processes, plankton and fish.
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- 2022
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30. An individual-based model for simulating the ecosystem dynamics of Jiaozhou Bay, China.
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Xing, Lei, Zhang, Chongliang, Chen, Yong, Shin, Yunne-Jai, Verley, Philippe, Yu, Haiqing, and Ren, Yiping
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- *
SIMULATION methods & models , *OPERATIONS research , *ECOSYSTEM dynamics , *ECOLOGY , *ENVIRONMENTAL sciences - Abstract
The Object-oriented Simulator of Marine ecoSystem Exploitation (OSMOSE) is one of the end-to-end models developed for ecosystem dynamic simulation and management strategy evaluation (MSE) in support of ecosystem-based fishery management (EBFM). However, the implementation of such integrated models has been limited due to lack of data, and their performance in advising fisheries management has been rarely evaluated. We developed an end-to-end model (OSMOSE-JZB) representing organisms of high and low trophic levels in the Jiaozhou Bay, a temperate bay in China with limited available data. We evaluated the performance of the model for simulating the ecosystem dynamics by comparing the model-predicted species biomass, size structure, trophic level, and mortality with relevant data derived from scientific surveys and literature. In general, the model-predicted species biomass and size ranges were consistent with observations. However, the size structure of the two dominant fish species showed some discrepancies between the model simulations and observations. The predicted mean trophic levels from OSMOSE-JZB were closer to the values derived from an Ecopath model of the same region, compared to the values derived from empirical isotope analysis. The model's output suggested that predation mortality appeared to be the main source of mortality for younger individuals compared to starvation and fishing mortality. This study suggests that the OSMOSE-JZB performs well under a data-poor situation and can be considered as a baseline ecosystem model for developing EBFM. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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31. Spatial and temporal dynamics of predator-prey species interactions off western Canada.
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Fu, Caihong, Olsen, Norm, Taylor, Nathan, Grüss, Arnaud, Batten, Sonia, Liu, Huizhu, Verley, Philippe, Shin, Yunne-Jai, and Link, Handling editor: Jason
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- *
FISHERY management , *COASTAL zone management , *PREY availability , *POPULATION dynamics , *PREDATION , *MARINE ecology , *SPATIAL ability , *TIME management - Abstract
Ecosystem models are valuable tools for informing fisheries management due to their ability to simulate the spatial dynamics of modelled species, their trophic interactions, and their responses to fishing in an ecosystem context. In this study, we developed an OSMOSE (Object-oriented Simulator of Marine Ecosystems Exploitation) model for the Pacific North Coast Integrated Management Area (PNCIMA) ecosystem off western Canada, which simulated the entire life cycle of six key species and for the first time integrated spatial population structure and "background" taxa. Background taxa are of secondary importance for the study at hand but have the potential to be important prey or predators of the key species. The primary aim of the study was to explore how the population dynamics of the key species differed over time and different management areas, with results focusing on Pacific Herring (Clupea pallasii) and Pacific Cod (Gadus macrocephalus) that have been assessed on a single-species basis in the last 5 years. Results found that the population dynamics of a specific species varied in different management areas due to differences in species interactions particularly in the form of predation mortality, which supports the current area-specific assessment and management framework. The study also indicated that increasing predation mortality may have caused the decline of the Pacific Cod populations. By contrast, increasing starvation mortality was found to be a limiting factor for the Pacific Herring populations. The discoveries from these OSMOSE simulations provide important information for fisheries management within the PNCIMA ecosystem. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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32. Exigência conceptual do trabalho prático: abordagem multidisciplinar de análise do discurso pedagógico na aula de ciências.
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Ferreira, Sílvia and Morais, Ana Maria
- Abstract
Copyright of Revista Práxis Educativa is the property of Revista Praxis Educativa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2017
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33. VERS DES TRANS(ES)IMMERSIONS SYMBIOSE-EXTASE-OSMOSE-VERTIGE.
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ANDRIEU, Bernard
- Abstract
Copyright of Societes is the property of De Boeck Universite and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2016
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34. Modelling food web structure using an end-to-end approach in the coastal ecosystem of the Gulf of Gabes (Tunisia).
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Halouani, Ghassen, Ben Rais Lasram, Frida, Shin, Yunne-Jai, Velez, Laure, Verley, Philippe, Hattab, Tarek, Oliveros-Ramos, Ricardo, Diaz, Frédéric, Ménard, Frédéric, Baklouti, Melika, Guyennon, Arnaud, Romdhane, Mohamed Salah, and Le Loc’h, François
- Subjects
- *
FOOD chains , *COASTAL ecology , *CONTINENTAL shelf , *BIOMASS , *FISHING , *ECOSYSTEMS , *MATHEMATICAL models - Abstract
Given the ecological importance and high socio-economic value of the fishery of the Gulf of Gabes, an end-to-end model was applied to its continental shelf ecosystem to characterize the structure of the food web in the 2000s. This approach consisted in forcing a high trophic level model (OSMOSE) with an existing biogeochemical model (Eco3M-MED) representing the seasonal dynamics of the low trophic levels. The two models were linked through trophic interactions to represent the ecosystem dynamics from primary producers to top predators. In this study, we developed the multispecies, individual-based model OSMOSE in the Gulf of Gabes (OSMOSE-GoG). This model aims to capture the main processes that influence species life cycle and simulate the functioning of the ecosystem according to opportunistic predation process based on size selection and spatio-temporal co-occurrence between a predator and its prey. The spatial distribution of the eleven modelled species was derived from a Multi-Scale Species Distribution Modelling approach. We calibrated OSMOSE-GoG model with available data of biomass and fishing yield, using an optimization method based on evolutionary algorithms which is suitable for complex and stochastic models. Finally, OSMOSE-GoG was validated against independent data sets at different hierarchical levels: the individual (diet composition), population (mean size of commercial catch) and community levels (mean trophic level) following the Pattern-Oriented Modelling approach. The model outputs were overall consistent with the diet compositions and mean trophic levels derived from the ECOPATH model of the Gulf of Gabes (ECOPATH-GoG) and the observations of mean size of catches. The OSMOSE-GoG can be considered as a baseline model to investigate ecosystem responses to environmental changes and fishing management measures in the Gulf of Gabes. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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35. Marguerite Duras – Joseph Losey
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Podvin, Virginie
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Acteurs ,Scénario ,Paradoxe ,Osmose ,Correspondances - Abstract
Des affinités particulières se dessinent entre Marguerite Duras et Joseph Losey ainsi qu'en témoigne leur échange épistolaire soutenu. De multiples propositions, de lui à elle, sont émises. Les projets prennent peu à peu corps, des noms d'actrices sont évoqués. Malgré cela, aucune collaboration ne verra le jour. Cette étude se propose d'éclairer – à la lecture de plusieurs lettres – les tenants et aboutissants de cette rencontre manquée.
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- 2022
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36. Incorporating electrokinetic effects in the porochemoelastic inclined wellbore formulation and solution
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Vinh X. Nguyen and Youname N. Abousleiman
- Subjects
perfuração ,eletrocinética ,poço inclinado ,osmose ,poromecânica ,estabilidade ,drilling ,electrokinetic ,inclined wellbore ,osmotic ,poromechanics ,stability ,Science - Abstract
The porochemoelectroelastic analytical models and solutions have been used to describe the response of chemically active and electrically charged saturated porous media such as clays, shales, and biological tissues. However, these attempts have been restricted to one-dimensional consolidation problems, which are very limited in practice and not general enough to serve as benchmark solutions for numerical validation. This work summarizes the general linear porochemoelectroelastic formulation and presents the solution of an inclined wellbore drilled in a fluid-saturated chemically active and ionized formation, such as shale, and subjected to a three-dimensional in-situ state of stress. The analytical solution to this geometry incorporates the coupled solid deformation and simultaneous fluid/ion flows induced by the combined influences of pore pressure, chemical potential, and electrical potential gradients under isothermal conditions. The formation pore fluid is modeled as an electrolyte solution comprised of a solvent and one type of dissolved cation and anion. The analytical approach also integrates into the solution the quantitative use of the cation exchange capacity (CEC) commonly obtained from laboratory measurements on shale samples. The results for stresses and pore pressure distributions due to the coupled electrochemical effects are illustrated and plotted in the vicinity of the inclined wellbore and compared with the classical porochemoelastic and poroelastic solutions.Modelos analíticos poroelásticos incluindo acoplamento químico e elétrico e soluções têm sido utilizados paradescrever a resposta de meios porosos saturados ativos química e eletricamente tais como argilas, folhelhos e tecidos biológicos. Entretanto tais tentativas têm sido restritas a problemas de consolidação unidimensional os quais exibem limitações na prática não constituindo exemplos realistas para validação de soluções numéricas. Este trabalho apresenta formulações gerais dos modelos poroelásticos lineares incluindo acoplamento químico e elétrico e apresenta a solução de um problema de estabilidade de um poço perfurado através de uma formação saturada quimicamente ativa e ionizada tal como um folhelho submetido a um estado tridimensional de tensão. A solução analítica para esta geometria incorpora o acoplamento entre a deformação do sólido e o fluxo simultâneo de fluido e íons induzido pelos gradientes de poro pressão, potencial químico e potencial elétrico sob condições isotérmicas. O fluido residente na formação é modelado como uma solução eletrolítica composta de um solvente e cátions e anions dissolvidos. A abordagem analítica integra na solução o uso quantitativo da capacidade de troca catiônica (CTC) comumente obtida por medidas experimentais em amostras de folhelhos. Os resultados obtidos para as distribuições de tensões e poro pressão devido ao acoplamento eletroquímico são ilustrados e plotados na vizinhança do poço inclinado e comparados com as soluções clássicas poroelásticas com acoplamento químico.
- Published
- 2010
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37. Biaxial testing of canine annulus fibrosus tissue under changing salt concentrations
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Jacques M. Huyghe
- Subjects
inchamento ,colágeno ,osmose ,Donnan ,tecido cartilaginoso ,swelling ,collagen ,osmosis ,cartilaginous ,Science - Abstract
The in vivo mechanics of the annulus fibrosus of the intervertebral disc is one of biaxial rather than uniaxial loading. The material properties of the annulus are intimately linked to the osmolarity in the tissue. This paper presents biaxial relaxation experiments of canine annulus fibrosus tissue under stepwise changes of external salt concentration. The force tracings show that stresses are strongly dependent on time, salt concentration and orientation. The force tracing signature of are sponse to a change instrain, is one of a jumpin stress that relaxes partly as the new strain is maintained. The force tracing signature of a stepwise change in salt concentration is a progressive monotonous change in stress towards a new equilibrium value. Although the number of samples does not allow any definitive quantitative conclusions, the trends may shed light on the complex interaction among the directionality of forces, strains and fiber orientation on one hand, and on the other hand, the osmolarity of the tissue. The dual response to a change in strain is understood as an immediate response before fluid flows in or out of the tissue, followed by a progressive readjustment of the fluid content in time because of the gradient in fluid chemical potential between the tissue and the surrounding solution.A mecânica in vivo do anel fibroso do disco intervertebral é baseada em carregamento biaxial ao invés de uniaxial. As propriedades materiais do anel estão intimamente ligadas à osmolaridade no tecido. O artigo apresenta experimentos de relaxação biaxiais do anel fibroso de um tecido canino sob mudanças abruptas na concentração externa de sal. A assinatura da força devido à mudança brusca de salinidade resulta em uma progressiva e monótona mudança na tensão em direção a um novo valor de equilíbrio. Embora o número de amostras não permita nenhuma conclusão quantitativa, as tendências podem abrir uma luz no entendimento das interações complexas na direção das forças, deformações e orientação das fibras por um lado e a osmolaridade do tecido por outro lado. A resposta dual devido à uma mudança na deformação é compreendida como uma resposta imediata antes do fluido escoar para dentro ou para fora do tecido, seguido de uma progressiva readaptação da quantidade de fluido notempo devido ao gradiente do potencial químico entre o tecido e a solução externa.
- Published
- 2010
- Full Text
- View/download PDF
38. Desidratação osmótica de frutículos de jaca (Artocarpus integrifólia L.): aplicação de modelos matemáticos - DOI: 10.4025/actascitechnol.v31i2.1026
- Author
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Tatiana Sant'Anna de Souza, Modesto Antonio Chaves, Renata Cristina Ferreira Bonomo, Rilvaynia Dantas Soares, Ellen Godinho Pinto, and Iara Ribeiro Cota
- Subjects
secagem ,conservação ,glicose ,sacarose ,osmose ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Science (General) ,Q1-390 - Abstract
A desidratação osmótica tem sido sugerida como uma operação unitária importante, na transformação de frutos perecíveis em novos produtos com maior vida de prateleira e maior valor agregado. A aplicação de modelos matemáticos confiáveis torna possível prever o comportamento de diversos fenômenos que ocorrem no processo, bem como possibilita a redução do seu custo operacional. Este trabalho teve como objetivo o estudo da aplicação de modelos matemáticos para as variáveis perda de água, ganho de sólidos, pH e ATT, durante a desidratação osmótica dos frutículos de jaca em solução de sacarose a 64°Brix, para diferentes temperaturas (40, 50, 60 e 70°C) das soluções, no tempo de 2.880 min. O Modelo Decaimento Exponencial 2 se ajustou melhor aos dados experimentais de perda de água, constatando-se variação do coeficiente de determinação de 76,73 a 97,16%, enquanto para as variáveis SST e ATT, o Modelo Logístico ajustou-se melhor aos dados experimentais, obtendo variação de 80,5 a 98,2% e 89,5 a 99,4%. Já para o pH, o Modelo Decaimento Exponencial 1 obteve bom ajuste aos dados experimentais, com coeficientes de determinação variando de 80,5 a 98,2%.
- Published
- 2009
- Full Text
- View/download PDF
39. Desidratação osmótica de frutículos de jaca (Artocarpus integrifolia L.): aplicação de modelos matemáticos = Osmotic dehydration of jackfruit (Artocarpus integrifolia L.): application of mathematical models
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Tatiana Sant'Anna de Souza, Modesto Antonio Chaves, Renata Cristina Ferreira Bonomo, Rilvaynia Dantas Soares, Ellen Godinho Pinto, and Iara Ribeiro Cota
- Subjects
secagem ,conservação ,glicose ,sacarose ,osmose ,drying ,conservation ,glucose ,sucrose ,osmosis ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Science (General) ,Q1-390 - Abstract
A desidratação osmótica tem sido sugerida como uma operação unitáriaimportante, na transformação de frutos perecíveis em novos produtos com maior vida de prateleira e maior valor agregado. A aplicação de modelos matemáticos confiáveis torna possível prever o comportamento de diversos fenômenos que ocorrem no processo, bem como possibilita a redução do seu custo operacional. Este trabalho teve como objetivo oestudo da aplicação de modelos matemáticos para as variáveis perda de água, ganho de sólidos, pH e ATT, durante a desidratação osmótica dos frutículos de jaca em solução de sacarose a 64°Brix, para diferentes temperaturas (40, 50, 60 e 70°C) das soluções, no tempo de 2.880 min. O Modelo Decaimento Exponencial 2 se ajustou melhor aos dadosexperimentais de perda de água, constatando-se variação do coeficiente de determinação de 76,73 a 97,16%, enquanto para as variáveis SST e ATT, o Modelo Logístico ajustou-se melhor aos dados experimentais, obtendo variação de 80,5 a 98,2% e 89,5 a 99,4%. Já para o pH, o Modelo Decaimento Exponencial 1 obteve bom ajuste aos dados experimentais, com coeficientes de determinação variando de 80,5 a 98,2%.Osmotic dehydration has been suggested as an important unitary operation in the processing of perishable fruit into new products withgreater shelf live and aggregate value. The application of reliable mathematical models makes it possible to predict the behavior of several phenomena that occur in the process, enabling the reduction of operational cost as well. The objective of this paper was to studythe application of mathematical models to water loss, solid gain, pH and titratable acidity (TA) variables during osmotic dehydration of jackfruit in sucrose solution at 64ºbrix and at different concentrations of sucrose and different solution temperatures (40, 50, 60 and 70ºC), for 2,880 minutes. The exponential decay model 2 was better adjusted to water loss experimental data, with the determination coefficient ranging from 76.73% to 97.16%,whereas for the variables total soluble solids (TSS) and TA, the logistic model was better adjusted to the experimental data, obtaining a variation from 80.5 to 98.2% and from 89.5 to99.4%. For pH, the exponential decay model 1 obtained a good adjustment to the experimental data, with determination coefficients ranging from 80.5 to 98.2%.
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- 2009
40. ASSEMBLY OF A METHODOLOGY FOR DETERMINATION OF MEMBRANE EFFICIENCY IN PRESERVED SHALES
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Jhoao Villabona-Camacho, Sergio Orozco-Orozco, Zuly Calderón-Carrillo, and Néstor-F Saavedra
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eficiencia de membrana ,selectividad iónica ,prueba de potencial electroquímico ,estabilidad de pozo ,interacción química ,ósmosis ,rocas arcillosas ,actividad acuosa ,eficiência de membrana ,seletividade iônica ,prova de potencial eletroquímico ,estabilidade de poço ,interação química ,osmose ,rocas argilosas ,atividade aquosa ,membrane efficiency ,ionic selectivity ,electrochemical potential test ,wellbore stability ,chemical interaction ,osmosis ,shales ,water activity ,Energy industries. Energy policy. Fuel trade ,HD9502-9502.5 ,Chemical engineering ,TP155-156 - Abstract
Determination of Membrane Efficiency (ME) is a very useful tool in the study of the chemical component of wellbore stability since it is a variable input in chemical elastic models (Lomba, Chenevert & Sharma, 2000). This article presents a novel methodology for the determination of ME using the Electrochemical Potential Test (EPT) in shale rocks. This method is based on the development of correlations with Ionic Selectivity (IS) values in presence of NaCl, KCl and CaCl2 at diverse solution concentrations. The correlation, not reported previously in the literature, depends on the type of salt used. The EPT is a generic test easily applied to any rock type from any well or basin. It is simpler and quicker than other tests used for the ME determination, like the Pressure Transmission Test (PTT). Correlations between ME and IS are applicable to any type of argillaceous rock. Samples of unperturbed plugs with diverse properties belonging to different Colombian formations were used. The results obtained with the application of the proposed methodology indicate that it is possible to obtain IS and ME values through EPT in any type of argillaceous rock by applying the developed correlations.La determinación de la Eficiencia de Membrana (EM) constituye una herramienta útil en el estudio del componente químico en la estabilidad de pozo, ya que es una variable de entrada en el desarrollo del modelamiento químico elástico (Lomba et al., 2000). En este artículo se propone una metodología novedosa para la determinación de la EM de rocas arcillosas utilizando una Prueba de Potencial Electroquímico (PPE), mediante el desarrollo de correlaciones no reportadas con anterioridad en la literatura y dependientes del tipo de sal usada, con los valores de Selectividad Iónica (SI), en presencia de soluciones de NaCl, KCl y CaCl2 de diversas concentraciones. La PPE es una prueba genérica que puede ser aplicada fácilmente a cualquier tipo de roca, de cualquier pozo, cuenca o campo, y es más sencilla y rápida que otras pruebas usadas en la determinación de la EM como la Prueba de Transmisión de Presión (PTP). Las correlaciones obtenidas entre la EM y la SI son aplicables a cualquier tipo de roca arcillosa. Para la aplicación de la metodología propuesta se utilizaron muestras de roca de diversas propiedades de formaciones Colombianas. Los resultados obtenidos con la aplicación de la metodología propuesta muestran que es posible obtener valores de SI y valores de EM a través de la PPE en cualquier tipo de roca arcillosa, por medio de las correlaciones desarrolladas.A determinação da Eficiência de Membrana (EM) constitui uma ferramenta útil no estudo do componente químico na estabilidade de poço, já que é uma variável de entrada no desenvolvimento do modelamento químico elástico (Lomba et al., 2000). Neste artigo se propõe uma metodologia inovadora para a determinação da EM de rocas argilosas utilizando uma Prova de Potencial Eletroquímico (PPE), mediante o desenvolvimento de correlações não reportadas com anterioridade na literatura e dependente do tipo de sal usado, com os valores de Seletividade Iônica (SI), em presença de soluções de NaCl, KCl e CaCl2 de diversas concentrações. A PPE é uma prova genérica que pode ser aplicada facilmente a qualquer tipo de roca, de qualquer poço, bacia ou campo, e á mais simples e rápida que outras provas usadas na determinação da EM como a Prova de Transmissão de Pressão (PTP). As correlações obtidas entre a EM e a SI são aplicáveis a qualquer tipo de roca argilosa. Para a aplicação da metodologia proposta foram utilizadas amostras de roca de diversas propriedades de formações Colombianas. Os resultados obtidos com a aplicação da metodologia proposta mostram que é possível obter valores de SI e valores de EM através da PPE em qualquer tipo de roca argilosa, por meio das correlações desenvolvidas.
- Published
- 2009
41. Incorporação de óxido de grafeno em membranas compostas de poliamida visando a melhoria de desempenho em sistemas de osmose inversa
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Rafael Isidoro da Silva, Kátia Cecília de Souza Figueiredo, Cristiano Piacsek Borges, and Thiago Henrique Rodrigues da Cunha
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Óxido de grafeno ,Engenharia química ,Dessalinização da água ,Dessalinização ,Osmose inversa ,Osmose ,Membrana de poliamida ,Polimerização ,Polimerização interfacial - Abstract
CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior O constante crescimento populacional aliado ao desenvolvimento industrial tem gerado um consumo de água cada vez maior. Tendo em vista que a água potável é um recurso limitado, tecnologias capazes de tratar essa água são necessárias para evitar um cenário global de escassez nos próximos anos. A dessalinização via osmose inversa utilizando membranas é uma das estratégias adotadas para contornar essa situação. Dentre as propostas estudadas para melhorar o desempenho das membranas, destaca-se a inserção de óxido de grafeno na matriz polimérica devido à sua hidrofilicidade. Visando a melhoria das membranas, foi estudada neste trabalho a incorporação de óxido de grafeno ao suporte de polisulfona e à camada de poliamida. O suporte poroso foi preparado por meio da técnica de inversão de fases e a nanocarga foi incorporada na solução contendo a polisulfona em diferentes concentrações. A membrana de polisulfona foi caracterizada em um sistema de permeação gasosa onde obteve-se um valor médio de permeância de 456 GPU para o nitrogênio para a membrana sem óxido de grafeno e 1370 GPU para a membrana com a nanocarga na concentração de 0,2% m/m de GO. A camada densa da membrana foi sintetizada utilizando o método de polimerização interfacial. A formação da pele foi evidenciada através da microscopia eletrônica de varredura e pela redução na permeância através da membrana para o valor de 170 GPU para nitrogênio. A permeabilidade hidráulica das membranas foi determinada através da permeação em um sistema de osmose inversa. Notou-se tanto o aumento da permeabilidade de 2,7 para 3,4 L/h.m².bar quanto o aumentou da rejeição salina de 13,6 para 31,2% evidenciando a melhoria da membrana após a adição da nanocarga. Potable water has become a valuable, and sometimes, scarce resource due to population growth and the industrial activities. Therefore, technologies that can process and generate this product are necessaries to avoid a global scenario of water scarcity in the next years. Reverse osmosis desalination using membranes is one of the most used strategies today to produce potable water. There are many studies to improve membrane’s performance, one of them is incorporating graphene oxide into the polymeric matrices due to its hydrophilicity. In order to improve their performance, it was studied in this work the incorporation of graphene oxide on the support of polysulfone and polyamide film. The porous supports were prepared using the phase inversion method and the nanoparticles were added in the solution of the polysulfone on different concentrations. The polysulfone membranes produced were characterized on a gas permeation system. The average permeance using nitrogen was 456 GPU for the pure membranes and 1370 GPU for the membranes with 0,2% m/m graphene oxide. The dense layer of polyamide was synthesized through the interfacial polymerization method. Results of scanning electron microscopy confirmed the formation of a thin film layer. Gas permeation tests showed that the permeance reduced to 170 GPU using nitrogen. Hydraulic permeability was obtained by using a reverse osmosis system for permeation. It was observed that both permeability and salt rejection improved. Hydraulic permeability increased from 2.7 to 3.4 L/h.m².bar while salt rejection increased from 13,6 to 31,2%. These results showed that the nanoparticle improves membrane performance for desalination systems.
- Published
- 2021
42. Avaliação do processo de osmose inversa para concentração de suco de laranja e simulação da recuperação do etil butirato através da pervaporação com predição de propriedades
- Author
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Araujo, Wilson Andalecio de, Maciel, Maria Regina Wolf, 1955, Torres Alvarez, Mario Eusebio, Silva, Jose Carlos Rodrigues, Viotto, Luiz Antonio, Aznar, anca: Martin, Boss, Edinara Adelaide, Universidade Estadual de Campinas. Faculdade de Engenharia Química, Programa de Pós-Graduação em Engenharia Química, and UNIVERSIDADE ESTADUAL DE CAMPINAS
- Subjects
Juice ,Suco de laranja ,Acetaldeído ,Reverse osmosis ,Membrane ,Ethyl Butyrate ,Acetaldehyde ,Osmose ,Separação de membrana ,Pervaporation ,Pervaporação ,Predição (Logica) ,Prediction ,Aroma ,Simulation ,Simulação (Computadores) - Abstract
Orientadores: Maria Regina Wolf Maciel, Mario Eusebio Torres Alvarez Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica Resumo: Os processos de separação com membranas (PSM) têm sido considerados como alternativa a processos clássicos de separação. Esta é uma área de estudo que apresenta uma forte interdisciplinaridade. Há um crescente interesse nestes processos para diversas aplicações como, por exemplo, tratamento de efluentes industriais, desalinização de águas, purificação e concentração de correntes da indústria alimentícia. A separação, em geral, não envolve mudança de fase, o que significa economia no consumo de energia e operações a temperaturas moderadas. Na tecnologia de separação com membranas, os componentes das misturas líquidas ou gasosas são separados ao permearem de forma seletiva através de uma membrana. As membranas podem ser poliméricas ou cerâmicas. A corrente de alimentação é dividida em duas correntes de saída: a que permeou através da membrana (permeado) e a corrente concentrada retida (¿retentate¿). Estes processos têm sido aplicados no processamento de bebidas, sucos, e aromas. Neste trabalho, dois PSM foram estudados, a Osmose Inversa (OI) e a Pervaporação (PV). Experimentos em escala piloto foram realizados empregando-se o processo de OI (membrana de poliamida) para a concentração de suco de laranja a 20°Brix. Avaliou-se a retenção de compostos de voláteis (acetaldeído, metanol e etanol) monitorando-se as correntes de alimentação e permeado. Os resultados de retenção de aromas obtidos não foram satisfatórios. A membrana apresentou baixas retenções para os voláteis monitorados na temperatura usada para realização dos experimentos. Na segunda etapa do trabalho, o processo de PV foi avaliado para recuperação de um importante éster do suco de laranja, o etil butirato. O software PERVAP, um simulador Fortran essencialmente preditivo, foi empregado no estudo de desempenho do processo para duas membranas, polidimetilsiloxano (PDMS) e polioctilmetilsiloxano (POMS). Realizou-se a predição de propriedades de membranas poliméricas para incremento da capacidade preditiva do simulador. Foram empregados métodos de contribuição de grupos para predição das propriedades dos polímeros. Os dados de viscosidade preditos para o POMS viabilizaram a realização de cálculos para obtenção de parâmetros requeridos para operação do simulador. A abordagem proposta proporcionou maior versatilidade ao simulador Abstract: The membrane separation processes (MSP) have been considered as alternative for conventional separation processes. In this research area a strong interdisciplinarity is observed. There is an increasing of interest for these processes considering many aplications (e.g., industrial wastewater treatment, water desalination, purification and concentration of food industry streams). The separation usually does not requires phase change, which means energy savings and moderate temperatures. A membrane separation system separates an inlet stream into two effluent streams known as the permeate and the retentate. The permeate is the portion of the fluid that has passed through the membrane. Whereas the retentate stream contains the constituents that have been rejected by the membrane. The membrane can be polymeric or ceramic. These processes have been applied for processing beverages, juices and aromas. In this work, two of these processes were studied, Reverse Osmosis (RO) and Pervaporation (PV). Pilot scale experiments were accomplished using RO (poliamide membrane) for concentrating single strength orange juice at 20ºBrix. The retention of volatile compounds (acetaldehyde, methanol and ethanol) was evaluated by monitoring feed and permeate streams. The retention results obtained were unsatisfactory. The membrane presented low retention for monitored volatiles under studied temperature conditions. In the second stage of this work, the PV process was evaluated for recovering an important ester of orange juice, the ethyl butyrate. The PERVAP software, an essentially predictive Fortran simulator, was used for evaluating process performance considering two membranes, polydimethylsiloxane (PDMS) and polyoctylmethylsiloxane (POMS). It was accomplished the prediction of properties for polymeric membranes targeting the software predictivity improvement. Viscosity data predicted for POMS was crucial for calculating parameters required by simulator. The predictive approach proposed improved the software versatility Doutorado Desenvolvimento de Processos Químicos Doutor em Engenharia Química
- Published
- 2021
43. Estudo da influencia de substancias osmoticas sobre o automatismo, inotropismo e periodo refratario efetivo do atrio isolado de cobaio
- Author
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Molina, Neoclair, Sakate, Minoru, Universidade Estadual de Campinas. Faculdade de Odontologia de Piracicaba, Programa de Pós-Graduação em Ciências, and UNIVERSIDADE ESTADUAL DE CAMPINAS
- Subjects
Regulação osmótica ,Osmose ,Química fisiológica - Abstract
Orientador: Minoru Sakate Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba Resumo: Não informado Abstract: Not informed. Mestrado Farmacologia Mestre em Ciências
- Published
- 2021
44. Separação de misturas binarias por pervaporação e osmose inversa
- Author
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Perioto, Fabiano Romero, Maciel, Maria Regina Wolf, 1955, Cabral, Fernando Antonio, Guimarães, José Roberto, Pinto, Glaucia Maria Ferreira, Alvarez, Mario Eusebio Torres, Universidade Estadual de Campinas. Faculdade de Engenharia Química, Programa de Pós-Graduação em Engenharia Química, and UNIVERSIDADE ESTADUAL DE CAMPINAS
- Subjects
Modelos matemáticos ,Mathematical models ,Pervaporation ,Solution-diffusion model ,Reverse osmosis ,Misturas ,Modeling ,Separação de membrana ,Osmose ,Separação (Tecnologia) ,Simulation ,Simulação (Computadores) - Abstract
Orientador: Maria Regina Wolf Maciel Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica Resumo: Neste trabalho de tese, foram realizadas a modelagem e a simulação dos processos de separação pervaporação e osmose inversa aplicados a sistemas binários. A premissa empregada foi o desenvolvimento de metodologias de predição das variáveis de processo da pervaporação e osmose inversa independentes de dados experimentais destes processos; os dados necessários para a predição destas variáveis foram propriedades fundamentais dos componentes puros da alimentação. A partir de uma revisão bibliográfica dos modelos existentes para o processo de pervaporação, foi definida uma metodologia de predição das variáveis de processo baseado no modelo solução-difusão. A etapa inicial da metodologia foi o desenvolvimento de um programa de cálculo das composições de sorção na membrana, baseado no modelo UNIQUAC e no método de contribuição de grupos UNIFAC, adaptados ao uso de polímeros. O programa foi validado pela aplicação a sistemas ideais e não-ideais sob o ponto de vista termodinâmico. Os resultados empregando o modelo UNIQUAC apresentaram boaconcordância com os dados experimentais; no caso dos resultados obtidos via UNIFAC para solventes orgânicos obteve-se um bom ajuste dos dados experimentais, mas, no caso da água, os resultados obtidos pelo modelo não foram adequados. Na segunda etapa da metodologia, foram realizados o estudo da predição do coeficiente de difusão na membrana, a partir do modelo do volume livre, seguindo a abordagem de Fick e Maxwell-Stefan; a determinação dos parâmetros necessários ao respectivo modelo; a aplicação a casos estudos e uma análise paramétrica. Os resultados obtidos concordaram bem com os dados experimentais. Com isto, a partir dos valores de sorção e coeficientes de difusão, foi elaborado um programa para a predição do processo de pervaporação; o programa foi aplicado a casos estudos citados na literatura. Foi também estudada a aplicação da pervaporação ao sistema fenol-água, considerando uma membrana de poli (dimetil siloxano) como agente de separação. Os resultados concordaram bem com os dados experimentais disponíveis e mostraram que uma melhor seletividade e performance de separação foram obtidos em concentrações de fenol na alimentação inferiores a 0,2 % molar. A etapa final do trabalho foi a elaboração de um programa para simulação do processo de osmose inversa tendo como base um modelo derivado da mecânica-estatística. A partir dos parâmetros do modelo, foram preditos a rejeição e fluxo do permeado da mistura etanol-água em uma membrana de poliamida. O coeficiente de difusão de Maxwell-Stefan em alta pressão foi predito e empregado na simulação da osmose inversa Abstract: In this work, the modelling and simulation of pervaporation and reverse osmosis processes for binary mixtures were carried out. The development of prediction methodologies for process variables of pervaporation and reverse osmosis without the necessity of experimental data was the general guideline followed; the experimental data used in these methodologies were the fundamental properties of pure components of feed. Based on the literature review for available models for pervaporation process, a prediction methodology according to the solution-difusion model was choosen and developed. The inicial step for the methodology elaboration was the development of a software for sorption composition determination in the membrane, based on the UNIQUAC model and UNIFAC group contribution method, both suitable for polymer applications. The software was validated applying it forideal and non-ideal systems on thermodynamic viewpoint. The results obtained according to the UNIQUAC model agreed well with experimental data; in the case of the results obtained by the UNIFAC method when applied for organic solvents, it was obtained a good agreement with experimental data, but, on the other hand, for the water, the results showed that the model must be improved. In the second step of methodology development, the study of the prediction of the diffusion coefficient in the membrane according Fick and Maxwell-Stefan approaches, the determination of models parameters, the validation of the prediction method with experimental data and a parametric sensitivity analysis were carried out. The results agreed well with experimental data. So, using the sorption compositions and diffusion coeficients calculated, it was developed a software for pervaporation prediction; the software was applied for some cases of literature. It was also studied the application of pervaporation to phenol-water system using poly(dimethylsiloxane) as selective barrier. The results agreed well with available experimental data and showed that a best selectivity and separation performance were achieved for phenol concentration lesser than 0.2% molar in the feed side. The final step of this work was the development of a software for simulation of reverse osmosis process based on a mecanical-statistical model. By using the model parameters, the rejection and permeate flux of ethanol-water mixture were predicted in a poliamide membrane. The diffusion coefficient of Maxwell-Stefan in high pressure was predicted and used in the reverse osmosis simulation Doutorado Desenvolvimento de Processos Químicos Doutor em Engenharia Química
- Published
- 2021
45. Estudo do efeito da dobutamina (Dobutrex) R e da radiação laser sobre a ação hidrosmotica da vasopressina em bexiga de sapo 'in vitro'
- Author
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Franco, Wilson, Arbex, Samir Tufic, 1939-2017, Universidade Estadual de Campinas. Faculdade de Odontologia de Piracicaba, Programa de Pós-Graduação em Ciências, and UNIVERSIDADE ESTADUAL DE CAMPINAS
- Subjects
Radiação ,Osmose - Abstract
Orientador: Samir Tufic Arbex Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba Resumo: No presente trabalho é descrito e caracterizado o efeito de diversos agentes farmacológicos, em especial a Dobutamina e de um agente físico-radiação Laser - nos eventos que se seguem à interação da Vasopressina com os receptores da membrana de bexiga de sapo, e que são relacionados à síntese e inativação do 3'5'AMPc. O fluxo de água entre as duas faces da membrana foi medido gravimetricamente por meio da técnica de BENTLEY (1958) para preparações em formas de lobos e da técnica de PROCÓPIO e LACAZ-VIEIRA (1977), para preparações em forma de lâmina. Na ausência de Vasopressina, a Dobutamina ou aplicação de radiação Laser não provocou alteração da permeabilidade normal do epitélio à água. Em contraste, a ativação dos receptores adrenérgicos por Dobutamina (8x10-4M) provocou bloqueio significativo (da ordem de 31%) da ação hidrosmótica da Vasopressina 10mU/ml de banho). De maneira semelhante, a aplicação do Laser (10J/cm2) na face serosa bloqueou significativamente (da ordem de 34%) a resposta do tecido a uma nova dose de Vasopressina. Esse efeito não foi verificado quando a face mucosa da membrana foi exposta à radiação. Por outro lado, a associação do 3'5'AMPc com a radiação Laser promoveu aumento do fluxo de água, sugerindo que o agente físico pode ter apresentado efeitos antagônicos sobre o transporte de água, com efeito negativo sobre a produção de 3'5'AMPc, pelo complexo adenilciclase e com efeito positivo sobre a ação do nucleotídeo por inibição da enzima fosfodiesterase-nucleotídeo. Foi verificado também que o inibidor da fosfodiesterase, Teofilina, promoveu aumento significativo do fluxo hidrosmótico, por provocar aumento da concentração de 3'5'AMPc. Quando foi associada Dobutamina à Teofilina, observou-se diminuição da atividade hidrosmótica da metil-xantina, sendo essa ação regenerada, quase que na sua totalidade, pela adição ao banho do antagonista alfa-adrenérgico, Fentolamina. Esses resultados sugerem que a Teofilina atua não somente bloqueando a atividade da fosfodiesterase, como também estimulando o complexo adenilciclase-dependente, na conversão do ATP em 3'5'AMPc. Em contraste, quando da associação de Dobutamina, Vasopressina e um agente beta bloqueador, Propranolol, não ocorreu a restauração do efeito do hormônio anti-diurético. Por outro lado, a associação de agentes bloqueadores alía-adrenérgicos, Fentolamina ou Rauwolscina ao meio contendo Dobutamina e Vasopressina, levou à observação do pleno restabelecimento da ação da Vaso pressina, evidenciando a participação de receptor alfa2-adrenérgico no bloqueio da ação hidrosmótica do hormônio, caracterizando esse receptor como sendo um agonista da diurese. Os resultados obtidos quando da associação de Indometacina com a radiação Laser antes e depois do fluxo de água ter sido estimulado pela Vaso- I pressina, apontam para a possibilidade de que o Laser estimularia a produção I de Prostaglandinas neste tipo de epitélio, que por sua vez interferiria sobre a I atividade hidrosmótica da Vasopressina Abstract: In the present work the effects of several pharmacological agents in special Dobutamine and a physical agent-Laser radiation - on the events that follow the interaction of Vasopressin with membrane receptors related to syn¬thesis and inactivation of cyclic-AMP in the toad bladder, are described and characterized. Water flow across the membrane was measured gravimetrically by the technique of BENTLEY(1958) in sac preparations of the membrane, and by the technique of PROCÓPIO &: LACAZ VIEIRA (1977) in sheet preparations of the bladder. Dobutamine or the application of Laser radiation did not al¬ter the normal water permeability of the epithelium in the absence of Vaso¬pressin. In contrast, adrenoceptors activation by Dobutamine (8x10-4M) led to a significant (about 31%) blockage of the hydrosmotic action of Vasopressin. Similarly, low-energy Laser radiation (10/ Jcm2) blocked the tissue response to Vasopressin after the previously treatment of the membrane with the hor¬mone. This inhibitory effect was not observed when the mucosal face of the membrane was exposed to the Laser radiation. On the other hand, association of cyclic-AMP with Laser radiation pro¬moted an increase in the water flow suggesting that the physical agent may present dual effects on the water tran-sport, one being negative on the cyclic¬AMP production by the adenylate-cyclase complex and the other being positi've on the nucleotide action by phosphodiesterase - nucleotide inhibition. It was also seen that Theophylline - the phosphodiesterase inhibitor ¬stimulated water transport by increasing cyclic-AMP concentration in the tis¬sue. The association of Dobutamine with Theophylline led to a decrease in the methyl-xanthine hydrosmotic activity, being this effect restored almost com¬pletely by the presence in the serosal bathing solution of an alpha-adrenergic antagonist, Phentolamine. These results suggest that Theophylline acts not only by blocking phosphodiesterase activity, but also by stimulating adenylate¬cyclase-dependent complex in the conversion mechanism of ATP to cyclic-AMP. In constrast, when Dobutamine, Vasopressin and an beta-adrenergic an¬tagonist, Propranolol were associated, the hydrosmotic response of the tissue to Vasopressin was not restored. On the other hand, the association of alfa¬adrenergic agent Phentolamine or Rauwolscine to the Dobutamine and Vaso¬pressin serosal bathing solution restored the action of Vasopressin, evidencing alpha2-adrenergic receptor participation on the blockage of the hydrosmotic action of the hormone, further characterizing this receptor as one diuresis ag¬onist. The results obtained by the association of Indomethacin with Laser ra¬diation before and after the stimulation of water flow by Vasopressin point to the possibility that Laser radiation would stimulate Prostaglandins syn¬thesis in this tissue, interfering in this way with the hydrosmotic activity of Vasopressim Doutorado Farmacologia Doutor em Ciências
- Published
- 2021
46. Avaliação do processo combinado de desidratação osmotica e secagem na qualidade de cubos de mamão formosa (Carica papaya L.)
- Author
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El-Aouar, Anoar Abbas, Murr, Fernanda Elizabeth Xidieh, 1952-2013, Universidade Estadual de Campinas. Faculdade de Engenharia de Alimentos, Programa de Pós-Graduação em Engenharia de Alimentos, and UNIVERSIDADE ESTADUAL DE CAMPINAS
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Mamão ,Secagem ,Osmose ,Qualidade - Abstract
Orientador : Fernanda Elizabeth Xidieh Murr Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos Resumo: No presente trabalho avaliou-se a influência do processo de desidratação osmótica como pré-tratamento na secagem de cubos de mamão formosa (Carica papaya L.). O pré-tratamento osmótico foi conduzido a 30°C, com agitação 110rpm, utilizando-se dois tipos de soluções de sacarose 70oBrix: solução contendo lactato de sódio 2,4% em peso e ácido láctico 0,1M e solução contendo lactato de sódio 2,4% em peso e ácido cítrico 0,1M. O estudo da ~inética de desidratação osmótica mostrou que a solução contendo ácido cítr~coapresentou valor de perda de água (WL), ao final de 48 horas de processo, ligeiramente superior ao encontrado para a solução contendo ácido láctico. Comportamento contrário ocorreu para o ganho de sólidos (SG). O ajuste dos dados experimentais da desidratação osmótica foi realizado através de um modelo empírico de dois parâmetros e do modelo difusional para geometria cúbica, sem considerar encolhimento durante o processo. A etapa de secagem foi estudada através de um planejamento fatorial 22com triplicata no ponto central para a fruta "in natura" e desidratada osmoticamente. As variáveis avaliadas foram temperatura (40, 50, 60OC) e velocidade do ar de secagem (1,25; 2,25 e 3,25m1s).As respostas foram atividade de água, perdas de vitamina C e carotenóides totais e tempo de secagem. Os experimentos foram realizados em secador de leito fixo. O aumento da temperatura e velocidade do ar favoreceu à redução do tempo de secagem do produto final, cuja umidade foi de 30% em base úmida, conforme legislação para frutas secas. Tal fato foi mais pronunciado para a secagem da fruta "in natura". O ajuste dos dados experimentais foi realizado utilizando-se o modelo difusional para geometria cúbica, sem considerar encolhimento e um modelo empírico exponencial de dois parâmetros Abstract: Effect of osmotic dehydration as a pre-treatment to air drying of papaya(Carica papaya L.) cubes was studied. Two 70oBrix sucrose osmotic dehydration solutions were used: containing 2,4% w/w sodium lactate and O,1M lactic acid; and containing 2,4% w/w sodium lactate and 0,1M citric acid. Values of temperature and agitation to both solutions were 30°C and 110rpm, respectively. Water loss (WL) with the solution containing citric acid was higher than one contenting lactic acid. The opposite occurred with respect to solid gain (SG). The osmotic dehydration curves were fitted using a diffusional model for cubic geometry and an empiric model with two parameters, without considering shrinkage during processo Factorial experimental design methodology was used for the drying process, both "in natura" fruit and osmotic dehydrated one, in order to obtain a final product more similar to the fresh product and more stable microbiologically. The independent variables studied were the temperature (40, 50 and 60OC) and the air velocity (1,25; 2,25 and 3,25m1s).The dependent variables were water activity, vitamin C and carotenoid losses, and drying time. The experiments were made using of a fixed bed dryer. According to the kinetic study, increasing of temperature and air velocity led to a decrease of drying. This was more significant for "in nature" fruit drying. Drying curves were fitted using a diffusional model for cubic geometry, considering no shrinkage and an empiric two parameter exponential mode Mestrado Mestre em Engenharia de Alimentos
- Published
- 2021
47. Influencia da estrutura celular e da geometria da amostra na taxa de transferencia de massa do processo de desidratação osmotica de banana nanica (Musa cavendishi) e de mamão formosa (Carica papaya L.)
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Antonio, Graziella Colato, Murr, Fernanda Elizabeth Xidieh, 1952-2013, Menegalli, Florência Cecília, Park, Kil Jin, Universidade Estadual de Campinas. Faculdade de Engenharia de Alimentos, Programa de Pós-Graduação em Engenharia de Alimentos, and UNIVERSIDADE ESTADUAL DE CAMPINAS
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Microscopia eletrônica de varredura ,Desidratação ,Mamão ,Osmose ,Banana - Abstract
Orientador: Fernanda Elizabeth Xidieh Murr Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos Resumo: Neste trabalho foi estudada a transferência de massa na Banana Nanica (Musa cavendishi) e no Mamão Formosa (Carica papaya 1.) no processo de desidratação osmótica. Foi analisada a influência da geometria e estruturas celulares, para a verificação do mellior desempenho na transferência de massa. A etapa de desidratação osmótica foi conduzida com agitação constante de 80rpm e analisada através de um planejamento experimental fatorial 24-1com 3 repetições no ponto central para cada geometria estudada. As variáveis analisadas foram temperatura (30, 45 e 60°C), concentração da solução de sacarose (45, 55 e 65°Brix), concentração de ácido láctico (O, 0,05, 0,1M), e geometria da amostra (placa plana e cubo). As respostas analisadas foram perda de água, ganho de sólidos e atividade de água. A temperatura foi a variável que mais influenciou na perda de água e ganho de sólidos, seguida da concentração de sacarose da solução. A geometria de placa foi a que mais facilitou a perda de água no processo de desidratação osmótica tanto para a banana quanto para o mamão. O Modelo de Peleg e Azuara ajustaram-se bem os dados experimentais, sendo que os dados de equilibrio de perda de água que mais se aproximaram dos dados experimentais foram os calculado pelo Modelo de Azuara. Pela análise de imagens obtidas através da microscopia eletrônica de varredura foi possível verificar que as células da banana apresentam-se de forma alongada com presença de grânulos de amido e tanino, enquanto que as células do mamão apresentam-se forma oval. A geometria da amostra mostrou ser a variável que mais influenciou nas modificações ocorridas durante o processo de desidratação osmótica de ambas frutas, seguida da temperatura. Abstract: In this work was studied mass transfer in banana (Musa cavendish) and papaya (Carica papaya L.) in osmotic dehydration process. It was analyzed the influence of geometry and cells structures to verify the best performance in mass transfer. Osmotic dehydration was carried on with constant agitation of 80 rpm and analyzed through a factorial experimental design 24-1with 3 repetitions of central point for each geometry. Analized variables were temperature (30, 45 and 60°C), sucrose concentration (3,5; 4,5 and 5,5 M), lactic acid concentration (O; 0,05 and O,lM) and sample geometry (fIat plate and cube). Analyzed responses were water 1055,solid gain and water activity. Water loss and solid gain were influenced more by temperature and after by sucrose concentration. In osmotic dehydration process, fIat plate geometry facilitated water loss in both banana and papaya. Peleg and Azuara's models fitted well to experimental data, but equilibrium data were better approached when they were calculated by Azuara's model. Analyzing obtained images through electronic microscopy scanning it was possible to verify that banana cells presented elongated shape with starch granules and tanine, while papaya cells presented egg-shaped. The variable that caused more influence in occurred changes during osmotic dehydration was sample geometry and after the temperature. Mestrado Mestre em Engenharia de Alimentos
- Published
- 2021
48. Obtenção de extrato de banana (musa cavendishi) isento de polifenol oxidase por ultrafiltração e concentrado por osmose inversa
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Tanada, Patricia Sayuri, Jardini, Jose Gilberto, Jardine, Jose Gilberto, Menezes, Hilary Castle de, Massaguer Roig, Salvador, Universidade Estadual de Campinas. Faculdade de Engenharia de Alimentos, Programa de Pós-Graduação em Tecnologia de Alimentos, and UNIVERSIDADE ESTADUAL DE CAMPINAS
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Ultrafiltração ,Osmose ,Banana - Abstract
Orientador: Jose Gilberto Jardine Dissertação (mestrado) . Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos Resumo: O objetivo deste trabalho foi à obtenção de extrato de banana isento de polifenol oxidase por ultrafiltração e concentração por osmose inversa. Foi realizado o processamento de extração de suco de banana, com inibição prévia da enzima polifenol oxidase com solução de 0,15% de metabissulfito de sódio e 1 % de ácido ascórbico para evitar o escurecimento inicial. Posteriormente esta enzima ficou retida na etapa de ultrafiltração. Os processos de ultrafiltração foram realizados com membranas de polissulfona com peso molecular de corte de 20.000 daltons à duas pressões transmembranas, 6 e 8 bar. O processo à 6 bar foi melhor por apresentar fluxo de permeado mais estável e menor diminuição deste com o tempo e concentração. Para a osmose inversa foram utilizadas membranas de filme composto (HR 95) e foram realizados quatro processos, dois à pressão transmembrana de 40 bar, um do suco ultrafiltrado à 6 bar e outro à 8 bar, e dois processos à 60 bar, dos mesmos sucos ultrafiltrados. Os processos à 60 bar foram superiores, dentre eles o do suco ultrafiltrado à 6 bar devido ao maior fluxo de permeado (27,8 L/h.m²) e concentração do suco (31º Brix) e menor tempo de processo. Uma aplicação do extrato concentrado de banana é a produção de licor. O licor obtido de 190 GL estava amarelo claro e sem turvação. Pela análise sensorial realizada, 74% das pessoas gostaram do licor devido ao sabor e aroma de banana Abstract:The objective of this research was the production of a banana extract by ultrafiltration containing no polyphenol oxidase by ultrafiltration and its concentration by reverse osmosis. The extraction of the banana juice was effected after a prior inhibition of the enzyme polyphenol oxidase using a solution containing 0,15% sodium metabissulfite and 1 % ascorbic acid to avoid initial browning. Later, this enzyme was successfully retained by ultrafiltration. The processes of ultrafiltration were carried out using polysulfone membranes with a cut-off of 20.000 daltons at two transmembrane pressures, 6 and 8 bar. The process using apressure of 6 bar was better because of the more stable permeate flux, decreasing less with time and concentration. The processes of reverse osmosis were effected using thin film composite membranes (HR-95) and four experiments were carried out, two with a transmembrane pressure of 40 bar, one with the 6 bar ultrafiltered juice and the other with the 8 bar one, and two processes at 60 bar, with the same ultrafiltered juices. The processes at 60 bar were better, specially that with the 6 bar ultrafiltered juice, because of the higher permeate flux (27,8 L/h.m²) and concentration of the juice (31° Brix) and the shorter process' time. One application of the concentrated banana extract is the production of liqueur. Liqueur with 19° GL was produced presenting a light yellow, transparent appearance and no turbidity. A sensory evaluation indicated that 74% of the people liked the liqueur because of the taste and flavour of banana Mestrado Mestre em Tecnologia de Alimentos
- Published
- 2021
49. Desenvolvimento de doce de fruta em massa funcional de valor calorico reduzido, pela combinação de goiaba vermelha e yacon desidratados osmoticamente e acerola
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Ventura, Fernanda Cardoso, Pezoa García, Nelson Horacio, 1946, Garcia, Nelson Horacio Pezoa, 1946, Murr, Fernanda Elizabeth Xidieh, Moretti, Roberto Hermínio, Menezes, Hilary Castle de, Universidade Estadual de Campinas. Faculdade de Engenharia de Alimentos, Programa de Pós-Graduação em Tecnologia de Alimentos, and UNIVERSIDADE ESTADUAL DE CAMPINAS
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Yacon ,Goiaba ,Red guava ,Fructooligosaccharides ,Acerola ,Osmose ,Osmotic concentration ,West Indian cherry ,Continuous processing - Abstract
Orientador: Nelson Horacio Pezoa Garcia Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos Resumo: Ultimamente tem aumentado a preocupação pela relação entre dieta e saúde, estimulando o consumo de alimentos saudáveis, nutritivos e funcionais e ainda de valor calórico reduzido, que tenham nutrientes com potencial protetor de saúde. Esses alimentos além de satisfazer requerimentos nutricionais e sensoriais básicos desempenham efeitos fisiológicos benéficos que diminuiriam o risco de doenças crônicas cardiovasculares, cancerígenas ou outras. Existe uma grande variedade de produtos para fins especiais, sendo aqueles destinados a dietas de redução de açúcares um dos mais expressivos. Assim, as indústrias têm o desafio de desenvolver processamentos em condições amenas de operação, tempo e temperatura, provocando menores alterações de coloração, sabor e nutricionais. Com base nisso, a finalidade desse trabalho foi concentrar os nutrientes da goiaba vermelha e yacon, através da desidratação osmótica e desenvolver um doce em massa com as frutas desidratadas osmoticamente e acerola, de valor calórico reduzido através de processo contínuo. Primeiramente, foi realizado um estudo para otimizar a desidratação osmótica utilizando xarope de sorbitol e de sacarose. Os ensaios foram realizados utilizando planejamento fatorial completo, variando-se o tempo, temperatura e concentração da solução osmótica, visando a maximização da perda de umidade e minimização da incorporação de sólidos. Na desidratação osmótica utilizando xarope de sorbitol foram obtidas perdas de umidade de 35 a 43% % e incorporação de sólidos de 5,7 a 8% na goiaba vermelha e no yacon 53 a 55% de perdas de umidade e 6,02 a 6,46% de incorporação de sólidos. Os resultados obtidos mostraram que utilizando xarope de sorbitol se conseguem maiores perdas de umidade em relação ao xarope de sacarose, contudo há também uma maior incorporação de sólidos, mas isto seria irrelevante no caso de produtos de baixo valor calórico, nos quais o sorbitol é comumente utilizado, por apresentar um valor energético de 2,4kcal/g, enquanto que a sacarose fornece 4kcal/g. Outro objetivo foi também obter um doce em massa de goiaba vermelha, yacon e acerola, com um maior teor em sólidos de frutas que um produto convencional. Foram realizadas três formulações para análise sensorial, sendo utilizado o teste de aceitação. Os doces em massa tiveram boas médias de aceitação sensorial, variando de ¿gostei ligeiramente¿ a ¿gostei moderadamente¿, diferindo entre si (p< 0,05) nos atributos cor, sabor e impressão global, e não apresentando diferença significativa no atributo aroma. A formulação preferida foi com 50% goiaba vermelha, 30% acerola e 20% yacon, processada em tratamento térmico contínuo. Os resultados da caracterização química (pH, acidez e atividade de água) e física (sinerese, cor e textura) dos doces em massa mostraram concordância com os trabalhos encontrados na literatura. Através da avaliação microbiológica o produto foi considerado como ¿comercialmente estéril¿, indicando que o tratamento térmico foi eficiente para manter a estabilidade microbiológica do produto Abstract: Concern about the relation between diet and health has greatly increased recently, stimulating the consumption of healthy, nutritive and functional foods, preferably of reduced caloric value, containing potentially health-protecting nutrients. In addition to satisfying the basic nutritional and sensory requirements, these foods play a beneficial physiological role in decreasing the risks of chronic cardiovascular diseases, cancer and other diseases. A great variety of special purpose foods exist, those destined for low sugar diets being the most prominent. Thus modern industry faces the challenge of developing processes operating under mild time/temperature conditions so as to minimize alterations in color, flavor and nutritional quality. Based on this idea, the objective of this research was to concentrate the nutrients of red guava and yacon by osmotic dehydration and develop a reduced calorie solid preserve using the osmotically dehydrated fruits plus West Indian cherry by way of a continuous process. Initially the osmotic dehydration process was optimized using sorbitol and sucrose syrups. A complete factorial experimental design was used for these trials, varying the time, temperature and concentration of the osmotic solution, aiming at maximizing moisture loss and minimizing solids incorporation. Osmotic dehydration using sorbitol syrup resulted in moisture losses of from 35 to 43% and solids incorporation between 5.7 and 8% for red guava and moisture losses of from 53 to 55% for yacon with solids incorporation from 6.02 to 6.46%. The results showed that higher moisture losses were obtained using the sorbitol syrup than with the sucrose syrup, although the solids incorporation was also higher. However, in low calorie products this is irrelevant since sorbitol is frequently used in such products due to its low energy value of 2.4kcal/g as compared to 4kcal/g for sucrose. A further objective was to prepare a solid preserve from red guava, yacon and West Indian cherry containing higher fruit solids content than the conventional product. Three formulations were prepared for the sensory acceptance test. The three formulations received good mean scores for acceptance, varying from ¿liked slightly¿ to ¿liked moderately¿, with significant differences (p£0.05) amongst the three for the attributes of color, flavor and overall impression but with no significant difference for aroma. The most preferred formulation was that containing 50% red guava, 30% West Indian cherry and 20% yacon, processed by a continuous heat treatment. The results of the chemical (pH, acidity and water activity) and physical (syneresis, color and texture) characterizations agreed with those of similar studies reported in the literature. The microbiological evaluation showed the product to be commercially sterile, indicating that the heat treatment was efficient in maintaining the microbiological stability of the product Mestrado Mestre em Tecnologia de Alimentos
- Published
- 2021
50. Avaliação do processo de concentração osmotica para obtenção de banana passa
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Aguiar, Alessandra Mara Locatelli de, Moretti, Roberto Hermínio, 1940, Schmidt, Flavio Luis, Srebernich, Silvana Mariana, Garcia, Nelson Horacio Pezoa, Universidade Estadual de Campinas. Faculdade de Engenharia de Alimentos, Programa de Pós-Graduação em Tecnologia de Alimentos, and UNIVERSIDADE ESTADUAL DE CAMPINAS
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Osmosis ,Secagem ,Osmose ,Banana ,Drying - Abstract
Orientador: Roberto Herminio Moretti Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos Resumo: O Brasil é um país com característica agrícola e o desenvolvimento dos setores agroindustriais é de grande importância sócio-econômica e que devem ser explorados a fim de evitar o desperdício de alimentos, agregar valor aos produtos agrícolas e aumentar a renda dos produtores. A transformação industrial, à experiência de regiões e países bem sucedidos, mostra que pelo menos a transformação primária das frutas deve ser pensada pelos produtores. Isto porque é um prolongamento das atividades agrícolas, que objetiva transformar produtos perecíveis em produtos estáveis. A bananicultura é uma atividade de importância econômica e social, sendo cultivada na maioria dos países tropicais. O Brasil é o terceiro maior produtor e representa cerca de 9,0% da produção mundial, com uma área de 495 mil ha, superado apenas pela Índia e pelo Equador. O presente trabalho estudou o processo de concentração osmótica em banana nanica (Musa cavendishi) através de planejamento experimental completo com 3 variáveis independentes (tempo, espessura e concentração de ácido cítrico), utilizando soluções de açúcar invertido, à pressão atmosférica e temperatura constante de 45°C. As variáveis dependentes para os 17 experimentos realizados foram: perda de peso, perda de umidade, incorporação de sólidos, variação de sólidos totais, variação de sólidos solúveis e a relação brix / acidez (ratio) que indica o equilíbrio das características sensoriais do produto. Para identificar a melhor relação foram selecionados 4 experimentos com diferentes ratio. Estas amostras de banana préconcentradas osmoticamente foram secas em estufa com circulação forçada de ar quente a 60°C até atingirem um teor de 65% de sólidos totais. Foi realizada uma análise sensorial (teste de preferência) com as 4 amostras selecionadas. Os resultados obtidos com os experimentos mostram uma perda de umidade entre 25,13 a 38,16% no processo de concentração osmótica e um produto com boas características organolépticas Abstract: Brazil is a country with agricultural characteristics and thus the development of the agro-industrial sector is of great socio-economic importance and should be explored so as to avoid food wastage and increase the value of agricultural products and producer profit. Based on the experience of highly successful regions and countries, in industrial transformation, the primary transformation of fruits should be thought of by the producers, since this is really a prolongation of the agricultural activity, with the aim of transforming perishable products into stable ones. The culture of bananas is an economically and socially important activity, bananas being cultivated in the majority of tropical countries. Brazil is the third biggest producer, behind India and Ecuador, representing 9% of world production and occupying an area of 495 thousand hectares. This work studied the osmotic concentration of banana nanica (Musa cavendishi) using a complete experimental design with 3 independent variables (time, thickness and citric acid concentration), using invert sugar solutions, atmospheric pressure and a constant temperature of 45ºC. The variable dependents for the 17 experiments carried out were: weight loss, moisture loss, solids incorporation, variation in total solids, variation in soluble solids and the brix:acidity ratio, which indicates the equilibrium of the product sensory characteristics. Four experiments with different ratios were selected in order to identify the best ratio. These osmotically pre-concentrated banana samples were dried in a forced air incubator at 60ºC to a total solids content of 65%. A sensory preference analysis was carried out with the 4 samples selected. The results obtained showed moisture losses from 25.13 to 38.16% in the osmotic concentration process and a product with good organoleptic characteristics Mestrado Mestre em Tecnologia de Alimentos
- Published
- 2021
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