37 research outputs found

    Prediction of horizontal daily global solar irradiation using artificial neural networks (ANNs) in the Castile and León region, Spain

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    Producción CientíficaThis article evaluates horizontal daily global solar irradiation predictive modelling using artificial neural networks (ANNs) for its application in agricultural sciences and technologies. An eight year data series (i.e., training networks period between 2004–2010, with 2011 as the validation year) was measured at an agrometeorological station located in Castile and León, Spain, owned by the irrigation advisory system SIAR. ANN models were designed and evaluated with different neuron numbers in the input and hidden layers. The only neuron used in the outlet layer was the global solar irradiation simulated the day after. Evaluated values of the input data were the horizontal daily global irradiation of the current day [H(t)] and two days before [H(t−1), H(t−2)], the day of the year [J(t)], and the daily clearness index [Kt(t)]. Validated results showed that best adjustment models are the ANN 7 model (RMSE = 3.76 MJ/(m2·d), with two inputs ([H(t), Kt(t)]) and four neurons in the hidden layer) and the ANN 4 model (RMSE = 3.75 MJ/(m2·d), with two inputs ([H(t), J(t)]) and two neurons in the hidden layer). Thus, the studied ANN models had better results compared to classic methods (CENSOLAR typical year, weighted moving mean, linear regression, Fourier and Markov analysis) and are practically easier as they need less input variables

    Zoning of potential areas for the production of oleaginous species in Colombia under agroforestry systems

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    Producción CientíficaDue to the need to develop more agroforestry systems, the Moringa oleifera, Olea Europea, Glycine max, Brassica napus, Helianthus annuus, and Jatropha curcas are identified as unconventional species for their expansion under these systems in Colombia. With the Colombian Environmental Information System (SIAC) database, zoning was carried out according to the agroclimatic species requirements and optimal coverage for their production. As a result, a total area of 212,977.2 km2 was identified, mainly including the departments of Casanare, Arauca, Vichada, Guajira, Córdoba, Meta, Magdalena, Cesar, Tolima, and Cundinamarca. The species and associations species with the most options for productive expansion are Moringa (75,758 km2), Moringa, Jatropha, and Sunflower (42,515.1 km2), Moringa and Jatropha (37,180.4 km2), Jatropha (20,840 km2), Jatropha and Sunflower (17,692.1 km2), Olive (7332.1 km2), and Soybean (3586.3 km2). Of the potential agroforestry areas to their establishment, 36% correspond to herbaceous and/or shrubby vegetation, 34% to grasses, and 22% to heterogeneous agricultural areas. This research is the first step to representing the agronomic versatility of these promising species and their potential contribution to the diversification of the agri-food and agroforestry sectors

    Crude and refined oils from Elaeis guineensis: Facile characterization by FTIR and thermal analysis techniques

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    From an industrial perspective, fast characterization of raw materials provides an important tool for preventing manufacturing problems and contributes to assure the quality of the final products. In this work, several fast, cheap, and simple methods (Fourier transform infrared spectroscopy (FTIR) and various thermoanalytical techniques) were used for screening and characterization of crude and refined palm oils and other palm-derived products. The FTIR spectra allowed for ready distinction between mesocarp-derived products and those obtained from the kernel. The same applied to high-temperature differential scanning calorimetry (DSC) and differential thermal analysis (DTA) thermograms and the low-temperature DSC curves, in which the peak values and the presence or absence of certain peaks also permitted to differentiate among the various oils and fractions. Correspondences of mesocarp-derived oils with olein and kernel-derived oils with stearin were confirmed by both analytical methods and from the crystallization study. The relationship between the triglyceride composition and the FTIR and thermal profiles of the various palm-derived products has potential to be utilized as a facile quality control method in mill plants and laboratories

    Life cycle analysis of macauba palm cultivation: A promising crop for biofuel production

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    The 450 Scenario, which limits the increase in global average temperature to 2¿°C, makes it necessary to take steps towards a low-carbon economy. Since the energy sector is a major contribution to anthropogenic greenhouse gas (GHG) emissions, the production of biofuels can play a key role in strategies aimed at climate change mitigation. In this regard, the oil derived from macauba palm (Acrocomia aculeata), mainly constituted of saturated organic chains, has been claimed to hold promise for the production of liquid fuels. The high potential yield, diversity of co-products and various positive features of this emerging energy crop make it an interesting option both from a social and an environmental point of view. Nonetheless, a full environmental evaluation is still missing. In the study presented herein, the impacts produced in its plantation, cultivation and harvesting phases and the associated cumulative energy demand have been determined using a life cycle analysis methodology, in addition to shedding some light on its GHG intensity relative to the other energy crops it can displace. Excluding land use changes and biogenic CO2 fixed by the crop, it was concluded that to produce one ton of macauba fruit in Brazil, the system would absorb 1810.21¿MJ, with GHG emissions of 158.69¿kg CO2eq in the 20-year timeframe, and of 140.04¿kg CO2eq in the 100-year timeframe (comparable to those of African oil palm). Damage to human health, ecosystem quality, and resources would add up to 16¿Pt·t-1 according to Eco-indicator 99 methodology. In order to account for the uncertainty derived from improvement and domestication programs, which should affect current production levels, a sensitivity analysis for different productivities was performed. In all analyses, fertilization was found to be responsible for ca. 90% of the impacts, and hence special attention should be paid to the development of alternative fertilizer management schemes

    Bioenergy on islands: An environmental comparison of continental palm oil vs. local waste cooking oil for electricity generation

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    Producción CientíficaEnergy security on islands is a challenging issue due to their isolation from energy markets and fossil fuel dependence. In addition, islands’ average energy intensity has increased in recent years due to economic development. This research explores the environmental performance of two alternative non-variable bioelectricity feedstocks to increase energy resilience on islands. The study was developed for the Galápagos islands to address the environmental impacts from the direct use of waste cooking oil (WCO) and refined palm oil (RPO) to produce 1 MWh using the life cycle assessment methodological framework. A combination of primary and secondary data sources was used. The results show better performance for the electricity derived from WCO in all the impact categories considered when compared to RP

    Evaluation of urban sustainability in cities of the French Way of Saint James (Camino de Santiago Francés) in Castilla y León according to the Spanish urban agenda

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    Producción CientíficaThe emblematic FrenchWay of Saint James (Camino de Santiago Francés) crosses towns, cities, and Spanish regions to the Cathedral of Santiago de Compostela (Galicia, Spain), However, where is The French Way of Saint James going with respect to the urban sustainability of its host cities? As each city is unique and urban sustainability favors the revitalization and transition of urban areas, to know where to go, it is first necessary to establish a diagnosis that makes the different urban situations visible. In this article, the behavior of urban sustainability is analyzed in the six host cities of The French Way of Saint James in the Autonomous Community of Castilla y León, a region characterized by its link with the rural environment and its current depopulation problems. The data and indicators used are officially provided by the Spanish Urban Agenda, which, through the normalization of its values, are able to territorialize the SDGs at the local level and reflect the realities of the cities of Burgos, Astorga, Cacabelos, León, Ponferrada, and Valverde de la Virgen. The results make it possible to diagnose and compare these host cities, identifying weaknesses, skills, and opportunities that favor the promotion of action plans, local or joint (favored by The French Way of Saint James), in the multiple aspects of sustainability. In addition, they show that Valverde de la Virgen is the city with the best performance in terms of urban sustainability.Unión Europea - (FUSILLI project H2020-FNR-2020-1/CE-FNR-07-2020

    An example lignocellulosic waste reuse in two consecutive steps: sorption of contaminants and enzymatic hydrolysis

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    In this study, an example of the reuse and revalorization of lignocellulosic waste from carnauba palm (Copernicia prunifera) leaves, macauba palm (Acrocomia aculeata) endocarp (shell) and European stone pine (Pinus pinea) nut shell is presented for the first time. The physical-chemical adsorption of Rhodamine B (RhB) dye for the different materials is studied in detail, together with the thermodynamic feasibility and the spontaneous and endothermic nature of the biosorption process. Subsequently, the production of total reducing sugars (TRS) is compared by enzymatic hydrolysis (before and after the adsorption process of the RhB pollutant), confirming the viability of TRS production in all cases, with yields ranging from 65.9% for pine nut shell (after adsorption) to 74.9% for the carnauba endocarp and to 84.0% for carnauba leaves (before adsorption). Hence the use of lignocellulosic materials as adsorbents does not preclude their ulterior reuse for obtaining fermentable sugars by enzymatic hydrolysis

    Rhodamine B removal with activated carbons obtained from lignocellulosic waste.

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    By-products from the wax production process from carnauba palm (leaves), from the extraction of oil from macauba seeds (endocarp) and from pine nut production (shell) have been assessed for activated carbon production, using H3PO4 or CaCl2 for their chemical activation. The resulting activated charcoals have been thoroughly characterized by elemental and thermal analysis, X-ray diffraction, infrared spectroscopy, electron scanning microscopy and N2 adsorption behavior. Subsequently, their adsorption capacity for the removal of rhodamine B (RhB) from aqueous solutions has been evaluated by studying different parameters: contact time, pH, adsorbent dose, initial dye concentration and solution temperature. The adsorption of RhB followed Freundlich's model in all cases. Kinetic studies indicate that the pseudo-second order model can be used for describing the dynamics of the adsorption process. Thermodynamic parameters have also been evaluated, indicating its endothermic and spontaneous nature. Finally, a preliminary analysis of the impact of cellulose content in the carbon precursor materials has been conducted, by using a mixture of native cellulose with one of the lignocellulosic materials

    Phytochemical Profile and Activity against Fusarium Species of Tamarix gallica Bark Aqueous Ammonia Extract

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    French tamarisk, Tamarix gallica L. (family Tamaricaceae) is a deciduous tree that, like other halophytes, grows in a wide variety of saline habitats thanks to its powerful phenolics-based antioxidant system. Given that antioxidant properties are usually linked to the presence of compounds with antifungal properties, in the work presented herein the antimicrobial activity of T. gallica bark extract was investigated against four phytopathogenic species of genus Fusarium. According to the results of gas chromatography–mass spectroscopy, the phytochemical profile of the aqueous ammonia extract included 1-(2,4,6-trihydroxyphenyl)-2-pentanone; 3,5-dimethoxy-4-hydroxycinnam aldehyde; trans-squalene; 4-hydroxy-3,5-dimethoxy-benzaldehyde; dihydro-3-methylene-2,5-furandione; 1-(4-hydroxy-3,5-dimethoxyphenyl)-ethanone; and 4-hydroxy-3,5-dimethoxy-benzoic acid as main constituents. Concerning in vitro antifungal activity, EC90 effective concentrations in the 335–928 μg·mL−1 range were obtained against F. acuminatum, F. culmorum, F. equiseti, and F. graminearum, remarkably lower than those of two conventional fungicides (viz. mancozeb and fosetyl-Al). The antifungal activity of the extract was tested further in wheat and maize grain protection bioassays, confirming that the treatment effectively controlled F. graminearum at a concentration of 375 µg·mL−1. Given this promising activity, T. gallica bark extracts may be susceptible to valorization as a natural and sustainable biorational for Fusarium spp. control.Publishe

    Seasonal and sex-related variations in serum steroid hormone levels in wild and farmed brown trout Salmo trutta L. in the north-west of Spain

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    P. 720-728Serum steroid profiles were investigated in order to evaluate the potential use of circulating sex steroid levels as a tool for sex identification in brown trout. Changes in the serum concentrations of testosterone (T), progesterone (P), 17-β-estradiol (E2), and cortisol (F) in wild and farmed mature female and male brown trout, Salmo trutta L., were measured in each season (January, May, July, and October) in six rivers and four hatcheries located in the north-west of Spain. Serum cortisol levels in farmed brown trout were significantly higher and showed a seasonal pattern opposite to that found in wild trout. Because levels of the hormones under study can be affected by disruptive factors such as exposure to phytoestrogens (which alters the hypothalamic–pituitary–gonadal axis) and infection with Saprolegnia (which alters the hypothalamic–pituitary–adrenal axis), both factors are taken into account.S
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