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131.
Diego F. Roa Patricio R. Santagapita M. Pilar Buera Marcela P. Tolaba 《Food and Bioprocess Technology》2014,7(9):2723-2731
Starch-enriched fractions of amaranth grain were obtained from planetary ball milling and subsequently studied for particle size reduction, hydration properties, and crystallinity loss. Wide-angle X-ray scattering (WAXS) was used to evaluate the crystalline of starch-enriched fractions, using an iterative smoothing algorithm to estimate amorphous background scattering. This methodology was then used to determine initial crystallinity and monitor crystallinity loss during this process. The attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) showed that ball-milling treatment significantly decreased (p?<?0.05) the intensity ratios of the bands at 1,039 and 1,014 cm?1 corresponding to the crystalline/amorphous part of starch structure. Starch crystallinity degree decreased by ball milling due to starch amorphization during this process. An excellent correlation was found between crystallinity degree obtained by WAXS and ATR-FTIR data for the whole ball-milled-analyzed samples. The energy required for size reduction was satisfactorily explained using a generalized grinding equation. A decrease of span and median diameter (D 50) indicated sample homogenization during ball milling. Water absorption index and water solubility increased with crystallinity loss during process. The flour produced at the higher milling energy (6.52 kJ/g), with a mean size of 68?±?1 μm, showed a low crystallinity degree (<5 %), and high water absorption and solubility indexes in comparison to the starch-enriched fraction sample. Particle activation provided by ball-milling process can offer chances for starch application such as sorbent agent in food or pharmaceutical industries. 相似文献
132.
I.M. Martínez P. Velásquez L. Meseguer-Olmo A. Bernabeu-Esclapez P.N. De Aza 《Materials science & engineering. C, Materials for biological applications》2012,32(4):878-886
This work describes the evaluation of pure α-Tricalcium Phosphate (TCP) and silica containing TCP ceramics in the system Dicalcium Silicate–Tricalcium Phosphate (C2S–TCP) as a potential substrate for bone tissue engineering. The ceramics were soaked in dynamic simulated body fluid (SBF) for 2 weeks and characterized by SEM-WDS, XRD, and TEM analysis, and the results indicated that a carbonated hydroxyapatite (CHA) was formed on the surface of the ceramics. In addition, cell attachment assay showed that the ceramics supported the adult mesenchymal stem cells of human origin (hMSCs-A) adhesion and spreading, and the cells established close contacts with the ceramics after 24 h of culture. Also, cellular assays have shown a greater ability of hMSCs-A to express markers of the osteoblast phenotype (ALP, Col I, OC) in the C2S doped α-TCP ceramics, indicating osteoblastic differentiation as a result of the increased concentration of silicon in solid solution in α-TCP. These findings indicate that the C2S doped α-TCP ceramics possess good bioactivity, and biocompatibility, and might be promising for bone implant material. 相似文献
133.
C. Roldán A. Roldán J. Martínez-Moreno 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2012,16(5):785-795
Least-squares technique is well-known and widely used to determine the coefficients of a explanatory model from observations
based on a concept of distance. Traditionally, the observations consist of pairs of numeric values. However, in many real-life
problems, the independent or explanatory variable can be observed precisely (for instance, the time) and the dependent or
response variable is usually described by approximate values, such as “about £300\pounds300” or “approximately $500”, instead of exact values, due to sources of uncertainty that may affect the response. In this paper,
we present a new technique to obtain fuzzy regression models that consider triangular fuzzy numbers in the response variable.
The procedure solves linear and non-linear problems and is easy to compute in practice and may be applied in different contexts.
The usefulness of the proposed method is illustrated using simulated and real-life examples. 相似文献
134.
This work optimizes the application of electrochemical potentiokinetic reactivation (EPR) to assess the degree of sensitization (DOS) of AISI 316L and compares the large-scale and small-scale EPR with the aim of improving the study of the different zones of AISI 316L welded joints by using an electrochemical minicell. The optimized EPR allows to discriminate better than the standardized EPR among different DOS. Small-scale EPR shows greater sensitivity to assess the DOS than large-scale EPR: (i) at lower deformation levels; (ii) for shorter sensitization times; (iii) when localized microstructural regeneration is caused by the combined effect of deformation and subsequent sensitization. 相似文献
135.
Rosalía López-Ruiz Roberto Romero-González José Luis Martínez Vidal 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2016,33(11):1685-1692
The development and validation of a method to determine flonicamid and its metabolites as TFNA (4-trifluoromethylnicotinic acid), TFNG (N-(4-trifluoromethylnicotinoyl) glycine) and TFNA-AM (4-trifluoromethylnicotinamide) in bell pepper samples by ultra-high-performance liquid chromatography coupled to Orbitrap mass spectrometry (UHPLC-Orbitrap-MS) was performed. A fast and simple extraction procedure with acidified acetonitrile and salts (magnesium sulfate and sodium chloride) was used. The methodology was validated, checking for specificity, recovery, precision, limits of detection (LODs) and limits of quantification (LOQs). The recoveries ranged from 84% to 98%, and precisions were lower than 17%. Finally, LODs ranged from 1 µg kg–1 (flonicamid) to 6 µg kg–1 (TFNA-AM), while LOQs ranged from 10 µg kg–1 (flonicamid) to 30 µg kg–1 (TFNA-AM). Bell pepper samples were analysed and concentrations up to 98 µg kg–1 (flonicamid) were detected, although the sum of flonicamid and metabolites did not exceed the maximum residue limit (MRL) set by the European Union. 相似文献
136.
Francisco J. Fernandez-Luque David Pérez Félix Martínez Ginés Domènech Isabel Navarrete Juan Zapata Ramón Ruiz 《Ad hoc Networks》2013,11(3):907-925
DIA (Dispositivo Inteligente de Alarma, in Spanish) is an AAL (Ambient Assisted Living) system that allows to infer a potential dangerous action of an elderly person living alone at home. This inference is obtained by a specific sensorisation with sensor nodes (portables and fixes) and a reasoning layer embedded in a PC that learns of the users behaviour patterns and advices when actual one differs significantly of the normal patterns. In AAL systems, energy is a limited resource therefore sensor devices need to be properly managed to conserve energy. In this paper, we introduce the design and implementation of innovative and specific mechanisms at the sensory layer middleware which is capable of, first to discriminate spurious motion detections assuming that these signals do not resemble the patterns of real motion detections and, second to reduce the dynamics of messages by a sensor signal processing in order to compress the whole information in one single event. The middleware achieves power saving by modifying the raw information from sensors and adapting it to the predefined semantic of the reasoning layer. It manages the important task of data processing from sensors (raw information), and transfers the pre-processed information into the top layer of reasoning in a more energy efficient way. We also address the trade-off between reducing power consumption and reducing delay for incoming data. We present results from experiments using our implementation of these mechanisms at the middleware that comprises from node firmware to the PC driver. The number of messages of the proposed method with respect to the raw data is reduced by approximately 98.5%. The resources used in the PIR signal processing is reduced by approximately 85%. The resulting delay introduced is small (10–19 s) but system dynamics is slow enough to avoid contextualisation errors or reduction of system performance. We consider these results as very satisfactory. 相似文献
137.
Laura Sánchez-Hernández Mariano Higes María T. Martín María J. Nozal 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2016,33(3):442-451
A validated analytical method to determine seven neonicotinoids (dinotefuran, nitenpyram, thiamethoxam, clothianidin, imidacloprid, acetamiprid and thiacloprid) in sunflower seeds (hull and kernel) using HPLC coupled to electrospray ionisation mass spectrometry (ESI-MS) is presented. Sample clean-up based on a solid–liquid extraction, and the removal of lipid fraction, in the case of kernels, is proposed and optimised. Low limits of detection and quantification were obtained, ranging from 0.3 × 10–3 to 1.2 × 10–3 µg g–1 and from 1.0 × 10–3 to 4.0 × 10–3 µg g–1, with good precision, and recovery values ranged from 90% to 104% for hulls and kernels. The method was applied for the analysis of five thiamethoxam-dressed sunflower seeds and four non-treated seeds, where, besides thiamethoxam, residues of the other neonicotinoid, clothianidin, were also detected and confirmed via tandem mass spectrometry (LC-ESI-MS/MS). Finally, the presence of residues of thiamethoxam and clothianidin in collected sunflower seeds (hulls) coming from coated seeds confirmed the translocation of these neonicotinoids through the plant up to these seeds. 相似文献
138.
Javier Solano Martínez Jérôme Mulot Fabien Harel Daniel Hissel Marie-Cécile Péra Robert I. John Michel Amiet 《Engineering Applications of Artificial Intelligence》2013,26(7):1772-1779
The aim of this paper is to present experimental validation results of an energy management system for hybrid electrical vehicles based on type-2 fuzzy logic. The energy management system (EMS) is designed by extracting knowledge from several experts using surveys. The consideration of interval type-2 fuzzy sets enables modeling the uncertainty in the answers of the experts. The validation of the EMS is performed on a real-scale heavy duty vehicle equipped with different energy sources such as batteries, fuel cell system and ultracapacitors. Experimental results are strong evidence that type-2 fuzzy logic is wide adapted for performing the energy management in hybrid electrical vehicles. 相似文献
139.
Juan Gabriel Brida Juan Carlos Martín Concepción Román Raffaele Scuderi 《Networks and Spatial Economics》2017,17(3):911-934
Different solutions for the integration of high-speed rail (HSR) and air transport could be implemented, ranging from very basic integration to more sophisticated systems that include ticket and handling integration. This paper uses two statistical techniques, name cluster analysis and discrete choice models in order to investigate how different market segments have a determining influence in being more proactive to change to HSR for the second leg in multimodal trips. A discrete choice experiment is conducted to better understand passengers’ preferences. We obtain a number of clusters and estimate flexible choice models, taking into account the panel nature of stated preference data. We obtain a range of willingness-to-pay values for service quality attributes, finding results that can be used to infer policy conclusions about the real attractiveness of the Air-HSR integrated alternative. In this respect, clusters and schedule coordination, which reduces connecting time, are crucial to explain HSR attractiveness. 相似文献
140.
Marcela Trybula Tomasz Gancarz Wladyslaw Gasior Alain Pasturel 《Metallurgical and Materials Transactions A》2014,45(12):5517-5530
Physicochemical properties like density, surface tension, and viscosity of liquid binary Al-Li and Li-Zn alloys have been measured using draining crucible method. The experimentally measured surface-tension values have been compared to theoretical results based either on the Butler model or the compound formation model assuming the existence of the most favored A 1 B 2 and A 2 B 3 clusters. Several models for viscosity calculation have been also applied and discussed in confrontation with measured data. Finally, the clustering effects in the liquid Al-Li and Li-Zn alloys have been examined using two microscopic functions, i.e., the concentration fluctuation function in the long-wavelength limit and the Warren-Cowley short-range order parameter. 相似文献