186 research outputs found

    Hierarchical zeolites TNU-9 and IM-5 as the catalysts for cracking processes

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    [EN] The 10-ring zeolites TNU-9 and IM-5 were obtained by a desilication and evaluated in series of acid-catalysed cracking reactions. n-Decane and 1,3,5-tri-iso-propylbenzene cracking were performed as model reactions, while vacuum gas oil, polypropylene and polyethylene were cracked into add-value lower molecular weight chemicals. The catalytic performance improvement of hierarchical zeolites was rationalized by deep acid sites characterization in situ FT-IR studies of pyridine, carbon monoxide and 2,6-di-tert-butylpyridine sorption. Further, operando FT-IR-GC studies supported by 2D COS (two-dimensional correlation) analysis provided insight into cracking and coking of catalysts during polypropylene and polyethylene decomposition. It was found that NaOH-derived catalysts ensure the most upsurged acidity, in terms of number and accessibility of the sites, and then with better performance. In VGO cracking the connected mesopores added post-synthesis increased yields to propylene and middle distillates and lowered coke production. A bigger share of iso-olefins was observed both in VGO and polyolefins cracking products.KGM acknowledges the Grant No 2021/43/B/ST4/00307 form National Science Center, Poland. KAT acknowledges the Grant No 2020/37/B/ST4/01215 form National Science Center, Poland. For the purpose of Open Access, the author has applied a CC-BY public copyright licence to any Author Accepted Manuscript (AAM) version arising from this submission. JMT acknowledges the Grant MFA/2022/016 from Advanced Materials program supported by MCIN with funding from European Union NextGenerationEU (PRTR-C17. I1) and by Generalitat Valenciana. The study was carried out using research infrastructure purchased with the funds of the European Union in the framework of the Smart Growth Operational Program, Measure 4.2; Grant No. POIR.04.02.00-00-D001/20-00, "ATOMIN 2.0-ATOMic scale science for the INnovative economy". The open-access publication of this article has been supported by a grant from the Faculty of Chemistry under the Strategic Programme Excellence Initiative at Jagiellonian University.Tarach, KA.; Martínez-Triguero, J.; Valencia Valencia, S.; Wojciechowska, K.; Rey Garcia, F.; Góra-Marek, K. (2023). Hierarchical zeolites TNU-9 and IM-5 as the catalysts for cracking processes. Applied Catalysis B Environmental. 338. https://doi.org/10.1016/j.apcatb.2023.12306633

    A Randomized Study of Food Pictures-Influenced Decision-Making Under Ambiguity in Individuals With Morbid Obesity

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    Background and Aims In addition to craving responses to salient food cues, the anticipation of short-term rewarding consumption of palatable food may overrun the anticipation of long-term negative consequences of obesity. The present investigation addressed the potential interplay of food cravings and decision-making abilities in individuals with obesity. Method Study 1 included 107 bariatric surgery candidates with class 2/3 obesity (OB-group) and study 2 included 54 individuals with normal weight/pre-obesity (nonOB-group). In both studies, standardized questionnaires concerning food cravings, food addiction, and psychopathology were administered. A cue-reactivity paradigm was used to measure craving responses toward semi-individualized images of highly palatable, processed food/fruit (appetitive food cues) compared to images of raw vegetables (non-appetitive food cues). Decision-making was measured with a modified computerized version of the Iowa Gambling Task (IGT) with food pictures. Both groups were divided into two subgroups that were randomized to different IGT conditions. In one IGT condition the advantageous IGT card decks were covered by pictures of palatable, processed food or fruit and the disadvantageous decks by images of raw vegetables (= congruent condition), and in the other IGT conditionvice versa. Results Participants in the OB-group admitted on average higher craving responses toward palatable, processed food or fruit cues compared to pictures of raw vegetables. This was not the case in the nonOB-group. Contrary to our hypothesis, decision-making performance in both groups was worse when pictures of palatable, processed food or fruit were associated with advantageous IGT card decks compared to performance when those pictures were linked to the disadvantageous decks. The interference effect of food pictures processing on advantageous decision-making has been observed particularly in those individuals of the OB-group who exhibited high craving responses toward palatable, processed food cues or high levels of food addiction. Discussion The results indicate that food pictures processing interferes with decision-making, regardless of weight status. Opposed to the hypothesis, stronger tendencies to avoid than to approach pictures presenting processed, tasty food were observed. Further research should examine how cognitive avoidance tendencies toward processed, high energy food and approach tendencies toward healthy food can be transferred to real life situations

    European Mixed Forests: definition and research perspectives

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    peer-reviewedAim of study: We aim at (i) developing a reference definition of mixed forests in order to harmonize comparative research in mixed forests and (ii) briefly review the research perspectives in mixed forests. Area of study: The definition is developed in Europe but can be tested worldwide. Material and methods: Review of existent definitions of mixed forests based and literature review encompassing dynamics, management and economic valuation of mixed forests. Main results: A mixed forest is defined as a forest unit, excluding linear formations, where at least two tree species coexist at any developmental stage, sharing common resources (light, water, and/or soil nutrients). The presence of each of the component species is normally quantified as a proportion of the number of stems or of basal area, although volume, biomass or canopy cover as well as proportions by occupied stand area may be used for specific objectives. A variety of structures and patterns of mixtures can occur, and the interactions between the component species and their relative proportions may change over time. The research perspectives identified are (i) species interactions and responses to hazards, (ii) the concept of maximum density in mixed forests, (iii) conversion of monocultures to mixed-species forest and (iv) economic valuation of ecosystem services provided by mixed forests. Research highlights: The definition is considered a high-level one which encompasses previous attempts to define mixed forests. Current fields of research indicate that gradient studies, experimental design approaches, and model simulations are key topics providing new research opportunities.The networking in this study has been supported by COST Action FP1206 EuMIXFOR

    Vertical Configuration of a Side Scan Sonar for the Monitoring of Posidonia oceanica Meadows

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    [EN] Posidonia oceanica meadows are ecosystem engineers that play several roles in marine environment maintenance. In this sense, monitoring of the spatial distribution and health status of their meadows is key to make decisions about protecting them against their degradation. With the aim of checking the ability of a simple low-cost acoustic method to acquire information about the state of P. oceanica meadows as ecosystem indicators, ground-truthing and acoustic data were acquired over several of these meadows on the Levantine coast of Spain. A 200 kHz side scan sonar in a vertical configuration was used to automatically estimate shoot density, canopy height and cover of the meadows. The wide athwartship angle of the transducer together with its low cost and user friendliness entail the main advantages of this system and configuration: both improved beam path and detection invariance against boat rolling. The results show that canopy height can be measured acoustically. Furthermore, the accumulated intensity of the echoes from P. oceanica in the first 30 centimeters above the bottom is indirectly related to shoot density and cover, showing a relation that should be studied deeply.Funding for open access charge: Universitat Politècnica de ValènciaLlorens-Escrich, S.; Tamarit, E.; Hernandis, S.; Sánchez-Carnero, N.; Rodilla, M.; Pérez Arjona, I.; Moszynski, M.... (2021). Vertical Configuration of a Side Scan Sonar for the Monitoring of Posidonia oceanica Meadows. Journal of Marine Science and Engineering. 9(12):1-15. https://doi.org/10.3390/jmse912133211591

    Simultaneous Extreme-Ultraviolet Explorer and Optical Observations of Ad Leonis: Evidence for Large Coronal Loops and the Neupert Effect in Stellar Flares

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    We report on the first simultaneous Extreme-Ultraviolet Explorer (EUVE) and optical observations of flares on the dMe flare star AD Leonis. The data show the following features: (1) Two flares (one large and one of moderate size) of several hours duration were observed in the EUV wavelength range; (2) Flare emission observed in the optical precedes the emission seen with EUVE; and (3) Several diminutions (DIMs) in the optical continuum were observed during the period of optical flare activity. To interpret these data, we develop a technique for deriving the coronal loop length from the observed rise and decay behavior of the EUV flare. The technique is generally applicable to existing and future coronal observations of stellar flares. We also determine the pressure, column depth, emission measure, loop cross-sectional area, and peak thermal energy during the two EUV flares, and the temperature, area coverage, and energy of the optical continuum emission. When the optical and coronal data are combined, we find convincing evidence of a stellar 'Neupert effect' which is a strong signature of chromospheric evaporation models. We then argue that the known spatial correlation of white-light emission with hard X-ray emission in solar flares, and the identification of the hard X-ray emission with nonthermal bremsstrahlung produced by accelerated electrons, provides evidence that flare heating on dMe stars is produced by the same electron precipitation mechanism that is inferred to occur on the Sun. We provide a thorough picture of the physical processes that are operative during the largest EUV flare, compare and contrast this picture with the canonical solar flare model, and conclude that the coronal loop length may be the most important factor in determining the flare rise time and energetics

    Modelling approaches for mixed forests dynamics prognosis. Research gaps and opportunities

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    Aim of study: Modelling of forest growth and dynamics has focused mainly on pure stands. Mixed-forest management lacks systematic procedures to forecast the impact of silvicultural actions. The main objective of the present work is to review current knowledge and forest model developments that can be applied to mixed forests.Material and methods: Primary research literature was reviewed to determine the state of the art for modelling tree species mixtures, focusing mainly on temperate forests.Main results: The essential principles for predicting stand growth in mixed forests were identified. Forest model applicability in mixtures was analysed. Input data, main model components, output and viewers were presented. Finally, model evaluation procedures and some of the main model platforms were described.Research highlights: Responses to environmental changes and management activities in mixed forests can differ from pure stands. For greater insight into mixed-forest dynamics and ecology, forest scientists and practitioners need new theoretical frameworks, different approaches and innovative solutions for sustainable forest management in the context of environmental and social changes.Keywords: dynamics, ecology, growth, yield, empirical, classification

    Pilagá- Dependencia

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    El propósito de este proyecto radica en implementar SIU-Pilagá en dependencias de la Universidad Nacional de Córdoba.Fil: Gelatti, Sonia Andrea. Universidad Nacional de Córdoba. Secretaría de Planificación y Gestión Institucional. Dirección General de Tecnologías Informáticas; Argentina.Fil: Goye Pampliega, Maximiliano. Universidad Nacional de Córdoba. Secretaría de Planificación y Gestión Institucional. Dirección General de Tecnologías Informáticas; Argentina.Fil: Durand Pauli, Graciela. Universidad Nacional de Córdoba. Secretaría de Planificación y Gestión Institucional. Dirección General de Programación Presupuestaria; Argentina.Fil: Ensabella, Carla María. Universidad Nacional de Córdoba. Secretaría de Planificación y Gestión Institucional. Dirección General de Contabilidad y Finanzas; Argentina.Fil: Aveta, Amelia. Universidad Nacional de Córdoba. Secretaría de Planificación y Gestión Institucional. Dirección General de Contabilidad y Finanzas; Argentina.Fil: Marek, Marta Susana. Universidad Nacional de Córdoba. Secretaría de Planificación y Gestión Institucional. Dirección General de Contrataciones; Argentina.Fil: Montoya, Juan Antonio. Universidad Nacional de Córdoba. Secretaría de Planificación y Gestión Institucional. Dirección General de Tecnologías Informáticas; Argentina

    Registro de Evaluación de Proveedores de la UNC

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    Este proyecto tiene por propósito lograr la eficiencia y la eficacia de las contrataciones en la UNC.Fil: López, Liliana. Universidad Nacional de Córdoba. Secretaría de Planificación y Gestión Institucional. Dirección General de Contrataciones, Argentina.Fil: Cocco, María Fernanda. Universidad Nacional de Córdoba. Secretaría de Planificación y Gestión Institucional, Dirección General de Contrataciones; Argentina.Fil: Vazquez, Soledad. Universidad Nacional de Córdoba. Secretaría de Planificación y Gestión Institucional, Dirección General de Contrataciones; Argentina.Fil: Marek, Susana. Universidad Nacional de Córdoba. Secretaría de Planificación y Gestión Institucional, Dirección General de Contrataciones; Argentina.Fil: Mazzoni, Emilio. Universidad Nacional de Córdoba. Secretaría de Planificación y Gestión Institucional, Dirección General de Contrataciones; Argentina.Fil: Miguez, Natalia. Universidad Nacional de Córdoba. Secretaría de Planificación y Gestión Institucional, Dirección General de Contrataciones; ArgentinaFil: Savid, Luis. Universidad Nacional de Córdoba. Secretaría de Planificación y Gestión Institucional, Dirección General de Contrataciones; ArgentinaFil: Gisela, Sollazzo. Universidad Nacional de Córdoba. Secretaría de Planificación y Gestión Institucional, Dirección General de Contrataciones; ArgentinaFil: Moya, Paola. Universidad Nacional de Córdoba. Secretaría de Planificación y Gestión Institucional, Dirección General de Contrataciones; ArgentinaFil: Gelatti, Sonia. Universidad Nacional de Córdoba. Secretaría de Planificación y Gestión Institucional, Dirección General de Tecnologías Informáticas; Argentin
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