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141.
Acrylamide formation in a cookie system as influenced by the oil phenol profile and degree of oxidation 总被引:1,自引:0,他引:1
Gema Arribas-Lorenzo Vincenzo Fogliano Francisco J. Morales 《European Food Research and Technology》2009,229(1):63-72
The purpose of this study was to investigate the effect of the olive oil phenolic compounds as well as of thermoxidised oil
on the formation of acrylamide in a cookies system. Three virgin olive oils having different phenolic profile and a thermoxidised
sunflower oil were selected. Cookies were baked at 190 °C for different times (8–16 min) following a basic recipe where type
of oil was the variable. Additionally to acrylamide (AA), other parameters such as colour, moisture, antioxidant activity
(AOA), and hydroxymethylfurfural (HMF) were measured. Results showed that concentration and composition of phenolic moiety
of virgin olive oil significantly affect the acrylamide formation, particularly at prolonged baking time. Virgin olive oil
with a higher dihydroxy/monohydroxy ratio was more efficient in the AA mitigation and AA was reduced up to 20%. Colour and
AOA were not significantly different among the three types of oils. However, AA is dramatically increased when thermoxidised
oil is used with a parallel increase of browning and HMF. It was concluded that lipid oxidation products should be considered
as an important factor in acrylamide formation during baking of fat-rich products. 相似文献
142.
143.
A simplified version of the extension matrix algorithm has been proved to be useful for implementation on a cellular automata machine(CAM-6),Te algorithm and its implementation are described. 相似文献
144.
This paper presents Circe, an environment for the analysis of natural language requirements. Circe is first presented in terms of its architecture, based on a transformational paradigm. Details are then given for the various
transformation steps, including (i) a novel technique for parsing natural language requirements, and (ii) an expert system
based on modular agents, embodying intensional knowledge about software systems in general. The result of all the transformations
is a set of models for the requirements document, for the system described by the requirements, and for the requirements writing
process. These models can be inspected, measured, and validated against a given set of criteria.
Some of the features of the environment are shown by means of an example. Various stages of requirements analysis are covered,
from initial sketches to pseudo-code and UML models. 相似文献
145.
Individually interviewed 50 male undergraduates for 20 min about procedures used in confronting decision-making situations. The interviewer disclosed experiences, attitudes, and feelings similar to those revealed by the students 0, 2, 4, 8, or 12 times during the interviews. An intermediate number of interviewer self-disclosures resulted in significantly more students returning for a 2nd interview than did few or many self-disclosures. Results suggest that the use of a moderate number of interviewer self-disclosures may be an effective means of increasing counselor attractiveness and client approach responses to the counselor. (16 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
146.
Fausto?SargeniEmail author Vincenzo?Bonaiuto 《Analog Integrated Circuits and Signal Processing》2005,44(3):283-292
Cellular Non Linear Networks can be useful applied for the solution of several types of Partial Differential Equations (PDEs).
This paper will describe an analogue circuit implementation for the simulation of one-dimensional Reaction-Diffusion PDE with
the possibility to set different boundary conditions as well as to select different discretization methodologies.
Fausto Sargeni was born in Riano (ROMA) in 1961. He received the Dipl. Eng. degree in Electronic Engineering at the University of Rome “La
Sapienza" in 1987. In 1989 he jointed the Dept. of Electronic Engineering at the University of Rome “Tor Vergata" as Assistant
Professor. In 1998 he became Associate Professor. His research interests include analog VLSI circuits for non linear circuits
and high-speed interconnections.
Vincenzo Bonaiuto was born in Rome, Italy, in 1962. He received the Dipl. Eng. degree in Electronic Engineering at the University of Rome “La
Sapienza". In 1997 he received the the Ph.D. in Telecommunication and Microelectronics. In 1996 he jointed the Electronic
Engineering Dept. as Assistant Professor at the University of Rome “Tor Vergata” and, in 2002, he became Associate Professor.
His main research interests are in the area of non linear circuits, Artificial Neural Networks analogue/digital VLSI circuits
implementation. 相似文献
147.
This study evaluates the effectiveness of Fenton's oxidation (FO) process and ozone (O3) oxidation compared with a coagulation-flocculation (CF) process to remove effluent toxicity as well as colour and COD from a textile industry wastewater. Daphnia magna was used to test acute toxicity in raw and pre-treated wastewater. The operational parameters for each process were determined on the basis of complete toxicity removal. The FO process removed COD at a higher rate (59%) than O3 (33%) while colour removal was similar (89% and 91%, respectively). The CF process removed both COD and colour at rates similar to the FO process. A colour range of 150-250 platin-cobalt (Pt-Co) unit was assessed for toxicity. 相似文献
148.
Stochastic simulation of hourly global radiation carried out with Auto-Regressive Moving Average and Factor Analysis techniques is found unable to describe the statistical features of time sequences. A Markov transition-matrix approach operating on atmospheric transmittance provides a simple yet effective simulation device. Two novel sophisticated models, the transmittance transition tensor and the Gaussian mapping technique are not justified in this context. 相似文献
149.
The formal definition of a programming language in denotational style is taken as the basis for the automatic generation of its interpreter. The facilities available in GANDALF are exploited to implement and integrate such a generation technique in a GANDALF environment. 相似文献
150.
Antonella De Leonardis Vincenzo Macciola Giuseppe Lustrato Giancarlo Ranalli Ahindra Nag 《European Food Research and Technology》2010,230(3):405-410
In the last few decades, biotechnological applications of phenoloxidase enzymes have become an area of significant interest.
In this study, sunflower seeds, seedlings and defatted mill cake were investigated as possible plant source of polyphenoloxidase
(PPO). Noticeable variation of chlorogenic acid concentration in each raw material has undoubtedly proven that only sunflower
seedlings have significant amounts of active PPO. The activity of the enzymes was assessed by measuring the molar decrease
of caffeic acid. Isolated protein powders from each raw material confirmed the presence of PPO only in the seedlings. Catalytic
action of the PPO of seedlings was compared to that of the commercial laccase from Trametes versicolor. Sunflower PPO was selectively active on caffeic and chlorogenic acids, less active on ferulic acid and not active on mono-phenols
and gallic acid. Conversely, laccase was highly active on all the assessed phenols. PPO activity was good in a large range
of pH (4–8), whilst it was approximately halved in solutions containing 35% ethyl alcohol (v/v), 500 mg L−1 citric acid and finally 200 mg L−1 sulphur dioxide. In conclusion, sunflower seedlings can be considered a potential and interesting plant source of PPO. Sunflower
PPO could be used to oxidise selectively o-diphenols, for example in alcoholic and nonalcoholic beverages. 相似文献