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排序方式: 共有3616条查询结果,搜索用时 13 毫秒
91.
Manuel Gómez Jose Pardo Bonastre Oliete Pedro A Caballero 《Journal of the science of food and agriculture》2009,89(3):470-476
BACKGROUND: Most of rye flour is obtained by a gradual reduction system using roller flour mills, which generate different flour streams. The study of the different flour streams composition is necessary since it determines the flour quality and the flour uses. Four break streams and nine reduction streams were analysed for moisture, ash, starch, protein, damaged starch, falling number, amylose/amylopectin ratio, β‐glucans and colour. Mixing and pasting properties were also determined with a doughLAB and a Rapid Visco Analyser respectively. RESULTS: As the milling process advanced, moisture and starch content decreased but protein, ash, β‐glucans and damaged starch increased. The differences in composition are probably related to the effect of the roller mills and the increase in the contamination with bran. The absorption, development time, and pasting viscosity increased as the milling proceeded, in detriment of the peak time. The β‐glucan content was positively correlated to absorption, mixing tolerance index and pasting viscosity, and negatively correlated to peak time. CONCLUSION: Differences in composition, above all, in bran, showed different mixing and pasting properties in rye streams. The most different streams corresponded to the last streams in the break process, in the sizings and in the middlings. Copyright © 2008 Society of Chemical Industry 相似文献
92.
正坐落在上海南外滩老码头新规划区内的水舍,是一座仅有19个客房的四层精品酒店。建筑本身由建造于上世纪三十年代三层楼高的日本武装总部改建而成。酒店濒临黄浦江,与闪烁着璀璨灯光的浦东天际线隔江相对。如恩设计研究室(NERlHU DESIGN AND RESEARCH OFFICE)对这一建筑的改造设计理念基于"新"与"旧"的融合。对历史构造的选择性保留与新设计的完美拼合,让这座建筑本身重焕新生。 相似文献
93.
Gabriel Henrique Horta de Oliveira Paulo Cesar Corrêa Emílio de Souza Santos Pedro Casanova Treto Mayra Darliane Martins Silva Diniz 《International Journal of Food Science & Technology》2011,46(10):2077-2084
The desorption isotherms and thermodynamic properties of cocoa beans were obtained during the drying process of this product. The isotherms were determined by dynamic method for various temperature (25, 35, 45 and 55 °C) and relative humidity (RH) conditions (30, 40, 50, 60, 70 and 80%). Equilibrium moisture content data were correlated by the Guggenheim–Anderson–de Boer (GAB) model, which presented good fit to the data, according to statistical procedures. Equilibrium moisture content ranged from 5.90 to 16.67 d.b.; it increased with an increment in the RH and decreased with increased temperature at a constant RH. Enthalpy values for each model coefficient were encountered, ranging from ?90.05 to 545.96 kJ kg?1. The integral isosteric heat of desorption and differential entropy increased with decreased equilibrium moisture content, a tendency also found for Gibbs free energy. 相似文献
94.
Differential effect of common ligands and molecular oxygen on antimicrobial activity of silver nanoparticles versus silver ions 总被引:1,自引:0,他引:1
The antibacterial activity of silver nanoparticles (AgNPs) is partially due to the release of Ag(+), although discerning the contribution of AgNPs vs Ag(+) is challenging due to their common co-occurrence. We discerned the toxicity of Ag(+) versus a commercially available AgNP (35.4 ± 5.1 nm, coated with amorphous carbon) by conducting antibacterial assays under anaerobic conditions that preclude Ag? oxidation, which is a prerequisite for Ag(+) release. These AgNPs were 20× less toxic to E. coli than Ag(+) (EC??: 2.04 ± 0.07 vs 0.10 ± 0.01 mg/L), and their toxicity increased 2.3-fold after exposure to air for 0.5 h (EC??: 0.87 ± 0.03 mg/L) which promoted Ag(+) release. No significant difference in Ag(+) toxicity was observed between anaerobic and aerobic conditions, which rules out oxidative stress by ROS as an important antibacterial mechanism for Ag(+). The toxicity of Ag(+) (2.94 μmol/L) was eliminated by equivalent cysteine or sulfide; the latter exceeded the solubility product equilibrium constant (K(sp)), which is conducive to silver precipitation. Equivalent chloride and phosphate concentrations also reduced Ag(+) toxicity without exceeding K(sp). Thus, some common ligands can hinder the bioavailability and mitigate the toxicity of Ag(+) at relatively low concentrations that do not induce silver precipitation. Furthermore, low concentrations of chloride (0.1 mg/L) mitigated the toxicity of Ag(+) but not that of AgNPs, suggesting that previous reports of higher AgNPs toxicity than their equivalent Ag(+) concentration might be due to the presence of common ligands that preferentially decrease the bioavailability and toxicity of Ag(+). Overall, these results show that the presence of O? or common ligands can differentially affect the toxicity of AgNPs vs Ag(+), and underscore the importance of water chemistry in the mode of action of AgNPs. 相似文献
95.
A mathematical representation is developed for the turbulent flow field, temperature field, and tracer distribution in the
upper region of the liquid pool in continuous casting. The problem is formulated through the statement of the two-dimensional
turbulent flow equa-tions, which were then solved numerically, using the adaptation of a technique described by Spalding and
coworkers. The computed results for the velocity fields were found to be in good qualitative agreement with the results of
water model studies for both straight and radial flow nozzles. Furthermore, the predictions based on the model for the temperature
and tracer profiles within the pool seem to be consistent with expectations.
R. T. YADOYA, formerly Graduate Student, State University of New York at Buffalo 相似文献
96.
Antonio J. Suárez Fábrega José Manuel Bravo Caro Pedro J. Abad Herrera Rafael M. Gasca 《International Journal of Adaptive Control and Signal Processing》2014,28(12):1299-1324
In this paper, a new data‐driven fault‐detection method is proposed. This method is based on a new nonparametric system identification approach, which constitutes the principal contribution to this work. The fault‐detection method is a parametric model‐free approach that can be applied to nonlinear systems that work at various operating points. Not only can the fault‐detection process be applied to the steady state of each operating point, but it can also be applied to the transient state resulting from a change in the operating point. In order to detect faults, the proposed method uses an interval predictor based on bounded‐error techniques. The utilization of techniques based on bounded error enables system uncertainties to be included in an explicit way. This in turn leads to the possibility of obtaining interval predictions of the behaviour of the system, which include information on the reliability of the prediction itself. In order to show the effectiveness of the fault‐detection method, two examples are presented: in the form of a simulated process (counter‐flow shell‐and‐tube heat‐exchanger system) and an example of a real application (two‐tanks system). A comparison with two fault‐detection methods has also been included. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
97.
98.
99.
Paulo Santos Diogo Peixoto Inês Ferreira Ricardo Passos Pedro Pires Marco Simes Pedro Pouso-Ferreira Teresa Baptista Benjamín Costas 《International journal of molecular sciences》2022,23(3)
Photobacteriosis is a septicaemic bacterial disease affecting several marine species around the globe, resulting in significant economic losses. Although many studies have been performed related to the pathogen virulence and resistance factors, information regarding the host defence mechanisms activated once an infection takes place is still scarce. The present study was designed to understand innate immune responses of farmed juvenile gilthead seabream (Sparus aurata) after Photobacterium damselae subsp. piscicida (Phdp) infection. Therefore, two groups of seabream juveniles were intraperitoneally injected with 100 µL of PBS (placebo) or 100 µL of exponentially growing Phdp (1 × 106 CFU/mL; infected). The blood, plasma, liver, and head kidney of six fish from each treatment were sampled immediately before infection and 3, 6, 9, 24 and 48 h after infection for the broad screening of fish immune and oxidative stress responses. Infected animals presented marked anaemia, neutrophilia and monocytosis, conditions that are correlated with an increased expression of genes related to inflammation and phagocytic activity. Similar studies with different fish species and bacteria can be useful for the definition of health biomarkers that might help fish farmers to prevent the occurrence of such diseases. 相似文献
100.
Mingxuan Lu Prabhakar V. Gulgunje Pedro J. Arias-Monje Jeffrey Luo Jyotsna Ramachandran Yudhisthira Sahoo Sandip Agarwal Satish Kumar 《Polymer Engineering and Science》2020,60(9):2143-2151
Bi-component, polyacrylonitrile (PAN)/carbon nanotube (CNT) fibers were processed, at different core-sheath area ratios, by gel spinning. A percolated CNT network at 10 wt% CNT in the sheath enhanced electrical conductivity as compared to the neat PAN fiber, while PAN polymer in the core contributed to the good mechanical properties. Fibers with relatively thin sheath allowed overall CNT loading as low as 3.7 wt% to be made with good electrical conductivity, and PAN stabilization by Joule heating was demonstrated. Such fibers with combined good mechanical properties and electrical conductivity can also potentially be used for electrical heating of fabrics, for making smart textiles, and for electromagnetic interference shielding. 相似文献