31 research outputs found

    Frecuencia de riego en variedades tintas: Repercusión en la producción y la composición de la uva, durante un periodo bienal, en 4 regiones de España

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    Resumen La restricción hídrica es un aspecto limitante del cultivo del viñedo en muchas regiones, por lo que el riego constituye uno de los principales factores determinantes de su desarrollo en muchas zonas, que ha sido estudiado en diferentes ámbitos, pero la frecuencia de aplicación del riego, que afecta a su distribución en el suelo y puede influir en el comportamiento del viñedo, no ha sido suficientemente evaluada, por lo que su estudio resulta de gran interés en diversas condiciones de cultivo. El objetivo de este trabajo fue evaluar los efectos de cuatro frecuencias de riego deficitario del 30% ET0: 7 riegos por semana (T01), 2 riegos por semana (T03), 1 riego por semana (T07) y 1 riego cada dos semanas (T15), en la producción de uva y la composición de la baya. El experimento se desarrolló durante los años 2021 y 2022, en viñedos de Garnacha Tinta (en Badajoz: T03, T07, T15), Tempranillo (en Valladolid: T03, T07, T15), Syrah (en Albacete: T03 y T07) y Mencía (en Lugo: T01, T03, T07). Tanto la producción como la composición de la uva fueron determinadas en vendimia. Las diferentes frecuencias de riego han repercutido en el rendimiento y la calidad de la uva de forma variable según la variedad, la localización y el año. La producción de uva y la madera de poda se vieron ligeramente favorecidos por la frecuencia T07 con respecto a T03 en Garnacha y, sólo en la producción, en Tempranillo, mientras que ocurrió lo contrario en Syrah y Mencía. La concentración de azúcares se vio ligeramente favorecida por la frecuencia T07 en Syrah y, parcialmente, en Tempranillo. El pH del mosto no ofreció una respuesta apreciable derivada de la frecuencia de riego. La acidez total mostró valores ligeramente superiores de T07 en Garnacha y Tempranillo, pero algo más altos de T03 en Syrah y Mencía. El ácido tartárico apenas presentó una ligera tendencia favorable a T07 en Garnacha, mientras que el ácido málico mostró una tendencia ligeramente favorable a T07 en Garnacha y Mencía, pero beneficiosa para T03 en Syrah. El contenido de potasio y de polifenoles totales ofreció una clara variabilidad entre frecuencias de riego en general, aunque el primero mostró un ligero aumento del T03 con respecto al T07 en Mencía y el segundo un ligero aumento del T07 frente al T03 en Syrah. En definitiva, los efectos productivos y cualitativos derivados de la frecuencia de riego aplicada han tenido un alcance reducido, que, sin embargo, puede variar moderadamente en función de la variedad y del año

    Probing the 3D molecular and mineralogical heterogeneity in oil reservoir rocks at the pore scale

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    Innovative solutions have been designed to meet the global demand for energy and environmental sustainability, such as enhanced hydrocarbon recovery and geo sequestration of CO2. These processes involve the movement of immiscible fluids through permeable rocks, which is affected by the interfacial properties of rocks at the pore scale. Overcoming major challenges in these processes relies on a deeper understanding about the fundamental factors that control the rock wettability. In particular, the efficiency of oil recovery strategies depends largely on the 3D wetting pattern of reservoir rocks, which is in turn affected by the adsorption and deposition of contaminant molecules on the pores surface. Here, we combined high resolution neutron tomography NT and synchrotron X ray tomography XRT to probe the previously unobserved 3D distribution of molecular and mineralogical heterogeneity of oil reservoir rocks at the pore scale. Retrieving the distribution of neutron attenuation coefficients by Monte Carlo simulations, 3D molecular chemical mappings with micrometer dimensions could be provided. This approach allows us to identify co localization of mineral phases with chemically distinct hydrogen containing molecules, providing a solid foundation for the understanding of the interfacial phenomena involved in multiphase fluid flow in permeable medi

    Capturing 3D water layers and water filled micropores in carbonate rock by high resolution neutron tomography

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    Knowledge of micrometer scale wetting layers and microporosity in rocks is crucial for a deeper understanding of immiscible fluid displacement, and especially capillary trapping. It is an established fact that the amount of capillary trapping is a result from the competition between flow via wetting layers and piston like displacement. Despite the large amount of experimental work published, there are many open questions about fluid displacement mechanisms in complex porous media, particularly the role of microporosity in the disconnection and entrapment of the nonwetting phase. Here, we applied the state of the art neutron tomography technique with the best spatial resolution available at neutron imaging facilities to reveal the 3D distribution of water layers and water filled micropores in a carbonate rock. Our results revealed wetting layers with a non uniform thickness distribution completely covering the rock surface. During imbibition at a low capillary number, a marked increase in the amount of water filled micropores with the concomitant swelling of wetting layers were observed. This approach can be used as a platform to explore a huge range of interfacial phenomena, such as enhanced oil recovery and CO2 storag

    Unveiling 3D physicochemical changes of sugarcane bagasse during sequential acid alkali pretreatments by synchrotron phase contrast Imaging

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    Several pretreatment strategies focus on the removal of a significant part of lignin from plant cell walls, as it is considered the main barrier to the process of deconstructing biomass to simple sugars by hydrolytic enzymes. The ability to chemically differentiate and spatially locate lignins across cell walls provides an important contribution to the effort to improve these processes. Here, we present a novel approach using synchrotron phase contrast tomography to probe the physicochemical features of plant cell walls. In addition to the 3D cellular architecture, the distribution of dense packed lignin carbohydrate complexes or, simply dense lignin over larger regions and within cell walls has been successfully provided. We examined in particular the effect of the sequential H2SO4 and NaOH pretreatment on sugacane bagasse. Our results revealed that aggregates of dense lignin form elongated 3D structures in cell corners CC following the orientation of the sclerenchyma fibers; a remarkable result in the light of the conventional perception that lignin particles are discrete and roughly spherical. After the acid pretreatment, a considerable fraction of the dense lignin primarily located in CCs was removed; and it was further dissolved with the subsequent alkali treatment. Unexpectedly, the two step pretreatment did not contribute to the cellulose accessibility in terms of available surface area and porosity. This study provides new insights into the underlying mechanisms of biomass deconstruction by pretreatments; and the approach established here can be extended to other systems relevant to the bioenergy and biotechnology arena

    Effects of experimental infections with larvae of Eustrongylides ignotus Jäegerskiold, 1909 and Contracaecum multipapillatum (Drasche, 1882) Baylis, 1920 in rabbits Efeitos de infecções experimentais em coelhos com larvas de Eustrongylides ignotus Jäegerskiold, 1909 e Contracaecum multipapillatum (Drasche, 1882) Baylis, 1920

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    Rabbits were infected per os with 10 Eustrongylides ignotus L4 and with 50 Contracaecum multipapillatum L3 per rabbit, recovered from naturally infected freshwater fishes (Hoplias malabaricus) in order to evaluate the patogenicity of these two nematode species in mammalian host. Two rabbits (20%) infected with E. ignotus died before the fourth day post-inoculation (one after 51 and the other after 78 hours). Six rabbits (60%) were inappetent until the fifth day following experimental inoculation. No clinical signs in rabbits inoculated with C. multipapillatum were observed; nevertheless, eight (80%) animals were positive for this nematode species. Rabbits inoculated with E. ignotus, had gastric congestion with hematoma of the gastric wall in 60% of the cases. Peritoneum was congested in 20% of the animals with the presence of peritoneal abscess in 10% of the cases. All inoculated animals showed hyperemia of the gastric mucosa with hemorrhagic gastritis due to infections with E. ignotus. In C. multipapillatum inoculated animals, the hyperemia was followed by disruption of the epithelial mucosa in the sites of parasite attachment. In the gastric mucosa, miscellaneous leukocitary infiltrates, with multifocal necrosis reaching the submucosa in the infections with C. multipapillatum were observed under bright field microscopy. Perforating lesions in several organs, mainly in the gastric wall, pancreas and liver, always in the presence of a mixed inflammatory process, intensely fibrous, with hemorrhage and necrosis were observed in animals infected with E. ignotus.<br>Coelhos foram infectados experimentalmente per os com 10 larvas L4 de Eustrogylides ignotus (n= 10) e 50 L3 de Contracaecum multipapillatum (n= 50) coletados em traíras (Hoplias malabaricus) naturalmente parasitadas a fim de se avaliar a patogenicidade induzida por essas espécies de nematóides em mamíferos. Dois coelhos (20%) infectados com E. ignotus morreram antes do quarto dia pós-infecção (um após 51 horas e outro após 78 horas). Seis coelhos (60%) mostraram-se inapetentes até o quinto dia após a infecção experimental. Não foram observados sinais clínicos nos coelhos infectados com C. multipapillatum. À necropsia, oito (80%) mostraram-se positivos para essa espécie de nematóide. Os coelhos infectados com E. ignotus apresentaram congestão gástrica, com formação de hematoma na parede gástrica em 60% dos casos. O peritônio estava congestionado em 20% dos animais, e em 10% dos casos foi observada a presença de abscesso. Todos os animais infectados apresentaram hiperemia da mucosa gástrica com gastrite hemorrágica provocada pela infecção com E. ignotus. Nas infecções com C. multipapillatum, a hiperemia foi seguida por ruptura da mucosa nos locais de fixação do parasito, e na mucosa gástrica observou-se infiltrado leucocitário, com necrose multifocais alcançando a submucosa. Nas infecções com E. ignotus foram constatadas lesões perfurantes em diversos órgãos, principalmente na parede gástrica, pâncreas e fígado, sempre na presença de processo inflamatório misto, intensamente fibrótico, com hemorragia e necrose

    Evaluation of the conventional and synchrotron X ray tomography applied to heterogeneous oil reservoir rocks

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    Carbonate and sandstone reservoirs play an important role in oil industry as they host over 50 of the world s hydrocarbon reserves. For an accurately assessment of porosity and pore size distribution of such complex pore network, which affect directly the macroscopic characteristics of multiphase fluid flow, X ray computed microtomography micro CT emerges as a powerful tool. In contrast to lab based X ray micro CT XCT , synchrotron X ray micro CT SXCT images are commonly free of artefacts i.e. beam hardening and the unique properties of synchrotron sources enable the X ray imaging of complex and heterogeneous materials in greater detail, with higher quality, and short acquisition time. This work reports results of cone beam computed microtomography XCT in comparison with synchrotron computed microtomography SXCT applied to very heterogeneous carbonate and sandstone reservoir rocks. We analyze the quality of the image generated in terms of detection of details and artefacts, the advantages and limitation of each technique, as well as features like contrast, sharpness, and signal to noise ratio SNR . Although SXCT offers significant advantages over XCT, the latter gains in cost of operation, accessibility and user friendlines
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