Scientific Journals of INIA (Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria)
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    3042 research outputs found

    Comparative performance analysis of innovative separation chamber configurations: Numerical and experimental investigations

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    Aim of study: Novel configurations of separation chamber are proposed to resolve the critical issue of separation in agro-industrial equipment.Area of study: Dept. of Mechanical and Biosystems Engineering, Urmia, IranMaterial and methods: Precise and instrumented experimentation has been conducted to calibrate the computational fluid dynamics (CFD) methodology in the modeling and simulating chickpea pod separation. Mechanisms were selected based on optimizing separation efficiency, relative purification and required airflow as a criterion for energy consumption.Main results: Applying a guiding blade and suction fans may potentially increase the separation efficiency while reducing the relative purification and required airflow. The highest separation efficiency (95%), the lowest required airflow (545 m³/h) and the lowest pressure drop (16.3 Pa), were obtained by such configuration. Furthermore, the highest relative purification of 90% was achieved when the mechanism was free of blade and fans.Research highlights: To integrate the advantages of the above-mentioned configurations, a series-type assembling them is proposed to preserve the separation efficiency and relative purification at the highest level, meanwhile reducing the required airflow. Also, 15% enhancement in the separation efficiency and 302.8 m³/h reductions in the airflow were found as a crucial finding. The high correlation of experimental and theoretical CFD results is the key point to motivate the researchers for extension of similar case projects

    Quantity-to-intensity (Q/I) relationships can efficiently characterize intensively cultivated agricultural soils in Bangladesh for better potassium supplying capacity

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    Aim of the study: Firstly, to evaluate the K dynamics of soils through a quantity-intensity isotherm study; and secondly, to characterize the soils on the basis of quantity-intensity (Q/I) parameters.Area of study: Gazipur, BangladeshMaterial and methods: Eleven soils collected from major agro-ecological zones in Bangladesh were evaluated for their varying K dynamics parameters, and K supplying capacities of these soils were described.Main results: The Q/I plot showed both linear and polynomial relationships for soils in the study. The eleven soils had labile K ranging from 0.022 in Palashbari clay loam to 1.35 cmol kg-1 in Barisal clay. The latter soil had the highest equilibrium K activity ratio (0.003 mol L-1)1/2 and potential buffering capacity (PBC) (460.4 (cmol kg-1) (mol L-1)1/2). The PBC of soils for non-exchangeable pool (PBCne) was much higher than that of exchangeable pool (PBCe) in most soils. The largest amount of PBCne and PBCe occurred in Barisal clay, Gopalpur clay, Jhalokathi clay and Nachol loam which had a higher K desorption rate than all the other soils. The equilibrium exchangeable K, critical exchangeable K and equilibrium solution K of the soils varied widely (0.0006-0.035, 0.06-0.61 and 0.06-0.604 cmol kg-1, respectively). The added K was converted almost equally for the respective soils, with specific reference to the respective exchangeable and non-exchangeable pool for Barisal clay and Nachol loam.Research highlights: All the studied parameters revealed wide variations among the soils. The linear and polynomial relationships for soils can efficiently characterize intensively cultivated soils in Bangladesh

    Simulation of local head loss of drip-irrigation tape with integrated in-line emitters as a function of cross section

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    Aim of study: To investigate how the cross section of a drip-irrigation tape affects local head loss.Area of study: The work was carried out in the laboratory of Irrigation hydraulics, College of Water Conservancy and Environment, Three Gorges University, Yichang, Hubei province.Material and methods: Tapes with six different wall thicknesses were studied experimentally to determine the relationship between cross-section deformation, wall thickness, and pressure. Based on the experimental results, we determined the factors that influence local head loss in drip-irrigation tapes by numerical simulation and dimensional analysis.Main results: The cross-sectional shape of the drip-irrigation tape varied with pressure: under low pressure, the cross section was nearly elliptical. The cross-sectional shape of the tape strongly influenced the local head loss, which was inversely proportional to the 0.867th power of the flattening coefficient of the drip irrigation tape. We expressed the local head loss of a drip-irrigation tape equipped with integrated in-line emitters by considering the deformation of the cross section. Under the conditions used in this study, when the cross section is circular, the ratio of local head loss to frictional head loss was about 10% but, when the cross section is elliptical, this ratio increased to 15%.Research highlights: The shape of the cross section of a drip-irrigation tape is nearly elliptical under low pressure. Local head loss is inversely proportional to the 0.867th power of that is the flatting coefficient of the drip-irrigation tape. Local head loss is about 1.5 times for elliptical tape than circular tape

    Estimate of body growth curve and feed intake of free-range chickens receiving different levels of digestible lysine

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    Aim of the study: To adjust nonlinear Gompertz model to describe the body growth and feed intake (FI) of free-range chickens of the CPK (Color Plumé) strain, receiving different levels of digestible lysine (dig-Lys), from 21 to 77 days of age.Area of study: São Cristovão, Sergipe, Brazil.Material and methods: A total of 432 one-day-old unsexed chickens were used in the study. At 21 days of age, the birds were assigned to four treatments (0.85%; 0.97%; 1.09%; 1.21%) of dig-Lys, in a completely randomized design with four replicates, with 27 birds per experimental unit. The Gompertz model was used to estimate bird growth curves related to body weight (BW) and FI at each Lys level.Main results: The tests of comparison between the parameters of the Gompertz model for each Lys level showed that parameter A varied, while parameters B (0.0329) and C (45.819) did not differ significantly. In parameter A, the dig-Lys level of 0.97% provided the highest BW estimate at maturity and maximum BW at the inflection point.Research highlights: Use of non-linear models to predict nutritional requirements, helps farmers to optimize management decisions and, thus, maximize their profit. According to Gompertz model, it was possible to infer that the inclusion of 0.97% dig-Lys in the diet of mixed batches of free-range chickens of the CPK strain meets their nutritional requirements

    Effect of soil particle-size distribution (PSD) on soil-subsoiler interactions in the discrete element model

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    Aim of study: This work investigated the significance and mechanism for the effect of particle-size distribution (PSD) under different nominal radii using the discrete element method (DEM) and validated using the laboratory soil-bin results to accurately determine PSD.Area of study: Yangling, ChinaMaterial and methods: The experimental soil was Lou soil. Soil disturbance characteristics (soil rupture distance ratio, height of accumulated soil, soil density change rate) and cutting forces (draft and vertical) under different treatments were predicted and measured respectively.Main results: The ANOVA outputs showed that PSD significantly affected draft and vertical forces (

    Effect of finishing diet on carcass characteristics and meat quality of Mos cockerel

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    Aim of study: To evaluate the effect of different diets on carcass characteristics and meat quality from Mos free-ranged cockerel.Area of study: Galicia (NW Spain).Material and methods: Cockerels (n=75) were allocated to 3 groups (n=25) according to finishing diets: commercial fodder (CF), 50% wheat and 50% corn (WH) and 33% wheat and 66% corn (CR). Meat quality was assessed in terms of physicochemical, and nutritional features.Main results: The highest live and carcass weight were obtained in CF group. Meat from CF and CR groups were similar in moisture, protein and cholesterol content in drumstick cut, meanwhile in breast piece there were no significant differences (p>0.05) in intramuscular fat (IMF), ash, and lightness (L*). On the other hand, finishing diet affected L* and redness (a*) values, showing the highest L* values in meat samples from CF treatment (49.94 for drumstick) (p<0.01), whereas a* was superior in WH samples (11.30 and 4.61, for drumstick and breast, respectively) (p<0.001). Meat shear force test was not affected (p>0.05) by diets. Finally, the finishing feed affected (p<0.05) the fatty acid and amino acid profile in both cuts (drumstick and breast).Research highlights: Present study allowed to characterize for the first time Mos cockerels fed with different diets. Some carcass features obtained were higher than previous studies with other Mos categories, and some autochthonous and industrial breeds. Meat from cockerels was characterized by a high protein percentage and lower IMF

    Governance of knowledge and innovation in the Ibero-American agri-food system

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    Aim of study: Governance and the knowledge and innovation system (KIS) are interrelated concepts. Knowledge management best practices are linked to KIS performance. This article explores the governance of the leading research, development, and innovation institutes in Ibero-American agriculture, food, and agro-industry sector. The paper reports mapping of the governance of 20 agricultural research institutes.Area of study: Latin America and the Caribbean, Spain and Portugal.Material and methods: In total, 51 strategic objectives for effective governance were identified. Self-evaluation by the National Agricultural Research Institutes (NARIs) was validated at a workshop backed by FONTAGRO, a cooperation mechanism amongst Latin American and the Caribbean countries, Portugal and Spain, and the Ibero-American Network of NARIs.Main results: As a strength, the key dimension of NARIs appears to be coordination and cooperation. This result was acknowledged in the internal and external evaluations and supports previous research on the relevance of innovation networks in Latin America. By contrast, as a challenge, the key dimension appears to be demand articulation, followed closely by capacity building. Most of the institutes are also well-positioned to develop deeper ties with social and environmental challenges.Research highlights: In the medium and long term, NARIs should make efforts to improve the processes of organizational evaluation and learning, demand articulation, and strategic direction of the institutions. Improvement in management processes, in addition to best practices for social responsibility and gender equality, appear to be short-term priorities

    Tillage effects on soil properties, crop responses and root density of sweet pepper (Capsicum annuum)

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    Aim of study: Soil compaction causes an increase in bulk density, resistance to penetration, low diffusion of oxygen and water in the soil. Tillage is one of the techniques to alleviate compaction. The objective of this work was to evaluate the effects of tillage on sweet pepper grown in greenhouse soil.Area of study: The experimental work was conducted in a plastic greenhouse at the Experimental Station of the University of Almería (SE Spain).Material and methods: The soil was ploughed with a single pass with ripper to 15 cm depth and with rotavator to 10 cm depth. The control treatment was soil untilled. Crop dry matter production and root length growth and density of sweet pepper were evaluated, in addition to soil characteristics such as bulk density, resistance to penetration and soil matric potential.Main results: Tillage reduced soil bulk density from 1.70 to 1.60 kg L-1 in the 10-40 cm of soil depth. There was a notable reduction in irrigation (12%), total N applied (13%), drainage (91%) and N leaching (95%) in the tillage treatment. However, tillage did not improve significantly crop dry matter production and yield. The absence of tillage effect is possible due to a slight reduction in the bulk density of the soil.Research highlights: The tillage treatment produced a notable reduction in irrigation, total N applied, drainage and N leaching when compared to the control

    A two-step feeding of calcium salts of fish oil improves reproductive performance in Holstein cows

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    Aim of study: To examine the effects of a biphasic schedule of feeding n-3 fatty acids on dairy cows.Area of the study: Isfahan, Iran.Materials and methods: 140 lactating Holstein cows were allotted at calving into two groups of 70 animals and received one of two dietary treatments: 1) saturated fatty acids (SFA, containing 80% palmitic acid) or 2) calcium salt of fish oil (CSFO, containing 16% eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA)), with an n-6/n-3 FA ratio of approximately 7 for SFA and 5 for CSFO treatments. The dietary supplements were fed to the respective groups at 240 g/head.day from 0 to 21 days in milk, and 120 g/head.day from 22 to 150 days in milk. Milk yield was recorded biweekly and milk composition was evaluated monthly. The concentration of FA in the milk and blood was determined on d-90 of the experiment in 10 cows randomly selected from each group. Reproductive indices were recorded until d-150.Main results: The CSFO supplementation did not affect average milk yield, milk composition or milk somatic cell count (SCC); however, in some weeks it decreased milk SCC (p<0.05). Plasma concentrations of palmitic acid and n-3 FA as well as milk fat concentration of EPA and DHA increased in the CSFO-fed cows (p<0.05). Feeding the CSFO decreased open days (100 vs 119 days, p<0.05), service per conception and all service conception rates (p<0.05).Research highlights: The implementation of a two-stage feeding program of n-3 FA improved reproductive variables and reduced milk SCC in dairy cows

    Agronomic and chemical evaluation of hop cultivars grown under Mediterranean conditions

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    Aim of study: Evaluation of the agronomic performance and chemical profile of four hop cultivars grown under Mediterranean conditions.Area of study: The study was undertaken in Bragança, north-eastern Portugal.Material and methods: The newly introduced cultivars (‘Columbus’, ‘Cascade’ and ‘Comet’) were compared with the well-stablished ‘Nugget’. The field experiment was carried out between 2017 and 2019. Dry matter (DM) yield (plant and cones), tissue elemental composition and bitter acid and nitrate (NO3-) concentrations in the cones were assessed.Main results: ‘Comet’ was the most productive cultivar with the highest total DM yield (1,624 to 1,634 g plant-1), cone yield (572 to 633 g plant-1), and dry weight of individual cones (0.28 to 0.79 g cone-1). ‘Cascade’ showed the lowest average total DM yield (723 to 1,045 g plant-1). The year affected the average values of DM yield and the concentration of bitter acids in the cones, with ‘Cascade’ showing the highest sensitivity between cultivars. The concentrations of α and β-acids in the cones were within or close to the normal ranges internationally accepted for all cultivars. ‘Columbus’ exhibited the highest levels of α-acids, ranging between 12.04 % and 12.23%, followed by ‘Nugget’ (10.17–11.90%), ‘Comet’ (9.32–10.69%) and ‘Cascade’ (4.46–8.72%). The nutrient accumulation criteria in cone and leaf tissues seem to be a differentiating factor between cultivars with influence on bitter acid biosynthesis and biomass production.Research highlights: All cultivars showed notable performance in terms of DM yield and bitter acid concentration in the cones when compared to international standards

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    Scientific Journals of INIA (Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria)
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