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排序方式: 共有3026条查询结果,搜索用时 31 毫秒
991.
Alessandro Moncalvo Laura Marinoni Roberta Dordoni Guillermo Duserm Garrido Vera Lavelli 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2016,33(7):1116-1126
Skin powders and aqueous alcohol extracts were obtained from waste marcs from different grape varieties (Barbera, Nebbiolo, Pinot Noir, Chardonnay, Moscato and Müller-Thurgau). Both skins and extracts were analysed for the content of chemical contaminants: ochratoxin A (OTA), biogenic amines (BIAs), pesticides and metals. OTA was detected in low concentrations in Barbera, Moscato and Nebbiolo skins, but only in Barbera and Moscato extracts. Cadaverine, putrescine, ethanolamine and ethylamine were found in extracts at very low levels, while potential allergenic amines, tyramine and histamine, were never detected. Different pesticides were present in both skins and extracts. Pb and Cd were found in trace only in the powders, and K, Ca and Mg were the most abundant elements in both skin powders and extracts. Concentrations of the different contaminants were related to fibre content or total phenolics content of powders and extracts, respectively, in order to evaluate their use in the food sector. 相似文献
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The primary concern of the present paper is the regulation of an uncertain heat process with collocated boundary sensing and actuation. The underlying heat process is governed by an uncertain parabolic partial differential equation (PDE) with Neumann boundary conditions. It exhibits an unknown constant diffusivity parameter and it is affected by a smooth boundary disturbance, which is not available for measurements and which is possibly unbounded in magnitude. The proposed robust synthesis is formed by the linear feedback design and by the ”Twisting” second-order sliding-mode control algorithm, suitably combined and re-worked in the infinite-dimensional setting. A non-standard Lyapunov functional is invoked to establish the global asymptotic stability in a Sobolev space, involving spatial state derivatives of the same order as that of the plant equation. The stability proof is accompanied by a set of simple tuning rules for the controller parameters. The effectiveness of the developed control scheme is supported by simulation results. 相似文献
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Leonardo Lesmo Alessandro Mazzei Monica Palmirani Daniele P. Radicioni 《Artificial Intelligence and Law》2013,21(2):139-172
In this work we present the TULSI system (so named after Turin University Legal Semantic Interpreter), a system to produce automatic annotations of normative documents through the extraction of modificatory provisions. TULSI relies on a deep syntactic analysis and a shallow semantic interpreter that are illustrated in detail. We report the results of an experimental evaluation of the system and discuss them, also suggesting future directions for further improvement. 相似文献
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Alessandro Ricci Nicola Poccia Boby Joseph Antonio Bianconi 《Journal of Superconductivity and Novel Magnetism》2011,24(3):1201-1205
The lattice critical response in REFeAsO (RE=Pr, Nd and Sm) oxypnictides near the orthorhombic-to-tetrahedral structural phase transition is studied using ultra-high-resolution X-ray diffraction in the temperature range 4 to 250 K. The critical exponent of the structural phase transition ?? is found to decrease with decreasing RE size. The ?? values determined to be 0.212, 0.209 and 0.194, respectively, for PrOFeAs, NdOFeAs and SmOFeAs. Temperature hysteresis is observed for all the REFeAsO, with ??T being of the order of 2 to 3 K. The results are discussed in the frame of Fermi surface nesting induced structural transition in the pnictides. 相似文献
1000.
Calabria Marco; Jacquin-Courtois Sophie; Miozzo Antonio; Rossetti Yves; Padovani Alessandro; Cotelli Maria; Miniussi Carlo 《Canadian Metallurgical Quarterly》2011,25(2):193
Objective: It has been proposed that time, space, and numbers share the same metrics and cortical network, the right parietal cortex. Several recent investigations have demonstrated that the mental number line representation is distorted in neglect patients. The aim of this study is to investigate the relationship between time and spatial configuration in neglect patients. Method: Fourteen right-brain damaged patients (six with neglect and eight without neglect), as well as eight age-matched healthy controls, performed a time discrimination task. A standard tone (short: 700 ms and long: 1,700 ms) had to be confronted in duration to a test tone. Test tone differed of 100, 200, and 300 ms respect to the standard tone duration. Results: Neglect patients performed significantly worse than patients without neglect and healthy controls, irrespective of the duration of the standard tone. Conclusion: These results support the hypothesis that mental representations of space and time both share, to some extent, a common cortical network. Besides, spatial neglect seems to distort the time representation, inducing an overestimation of time durations. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献