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Examined whether the method of constant stimuli with the standard presented first produces a constant error that depends on adaptation level. 120 university students were shown 5 series of 5 pairs of standard and variable lines. They had to decide whether the standard or the variable was longer or shorter than the preceding variable, or standard, respectively. In order to establish when the constant error occurred, the point of subjective equality was determined for each response. It was found that the 1st response was nearly random. The constant error was present from the 2nd response, and its magnitude did not change in succeeding series, contrary to expectations from adaptation-level theory. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Research has been carried out to ascertai the effects of different processing systems on olive oil quality. Tests were performed in industrial oil mills that were equipped with both pressure and centrifugation systems. Results show that oils extracted from good-quality olives do not differ in free fatty acids, peroxide value, ultraviolet absorption and organoleptic properties. Polyphenols ando-diphenols contents and induction times are higher in oils obtained from good-quality olives by the pressure system because it does not require addition of water to the olive paste. The centrifugation system requires the addition of warm water to the olive paste and helps to obtain oils with a lower content of natural antioxidants. Oils obtained from poorquality or from ripe olives in continuous centrifugal plants are lower in free fatty acids than those obtained by the pressure system. Dr. Mario Solinas is deceased—May 23, 1993.  相似文献   
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Recent natural disasters have led crisis management organizations to revise their protocols so as to rely on the contribution of a wider range of actors, including simple citizens as well as expert operators, to support decision making activities. Reliable and timely information sharing among members of distributed teams of disaster responders has become paramount for the success of the overall crisis management process. In this paper we propose a crisis management system based on spreadsheet-mediated collaboration among on-site responders and decision makers. To share data a common spreadsheet artifact has been developed by using a participatory design approach which is accessed through mobile user interfaces. The evaluation results showed that the use of the spreadsheet artifact has resulted in more effective decision making relating to set of earthquake management scenarios in high-risk areas located in Italy.  相似文献   
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The combined use of calorimetric and catalytic methods for the investigation of the acid-base properties of oxide systems is discussed with reference to the authors' work on pure and doped zirconia samples, ceria-zirconia and ceria-lanthana solid solutions. Adsorption microcalorimetry of ammonia and carbon dioxide had been used to characterize the samples, whose chemical and thermal history was taken into account. The catalytic behavior of these samples in the conversion of 4-methylpentan-2-ol, route to 4-methylpent-1-ene (starting product for the manufacture of polymers of superior technological properties), had also been studied. On the basis of the calorimetric data, a rationale for interpreting the data for the transformation of 4-methylpentan-2-ol is formulated, which takes into account the role of the concentration and strength of the sites in governing the competition among the various mechanisms for dehydration and dehydrogenation.  相似文献   
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Polyurethane prepolymers prepared from toluene 2,4‐diisocyanate, toluene 2,6‐diisocyanate, and polypropylene glycol with a ratio between the isocyanate and hydroxyl groups equal to 2 were analyzed by 1H nuclear magnetic resonance (NMR) spectroscopy in acetone‐d6. Different temperatures and concentrations were used. Toluene 2,4‐dimethylurethane and toluene 2,6‐dimethylurethane were synthesized and used as model compounds to assign prepolymers signals. Measurements of spin–lattice relaxation time T1 by “inversion recovery” experiments were carried out on toluene 2,4‐diisocyanate, toluene 2,6‐diisocyanate, toluene 2,4‐dimethylurethane, toluene 2,6‐dimethylurethane, and polyurethane prepolymers. Differences in T1 times were used to interpret prepolymers spectra, by means of the strong observed effect on protons due to the presence of adjacent isocyanate groups. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 347–357, 2003  相似文献   
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With the Smart Grid revolution and the increasing interest in renewable energy sources, the management of the electricity consumption and production of individual households and small residential communities is becoming an essential element of new power systems. The electric energy chain can greatly benefit from a flexible interaction with end-users based on the optimization of load profiles and the exploitation of local generation and energy storage. This paper proposes a framework for the development of a complete energy management system for individual residential units and small communities of domestic users, taking into account both the power system and the final users’ perspectives. All the main elements of the framework are considered, and contributions are provided on the users’ habits profiling, electricity generation forecast, energy load, and storage optimization. Specifically, we propose a linear regression model to predict the photovoltaic panels production, a stochastic method to forecast the home appliances usage, and two optimization models to optimize the electricity management of residential users with the goal of minimizing their bills. The study shows that it is possible to reduce the energy bill of residential users through the electricity optimization driven by dynamic energy prices. Moreover, remarkable improvements of the electric grid efficiency can be achieved with the cooperation among users, confirming that services for the coordination of the demand of groups of users allow huge benefits on the power system performance.  相似文献   
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This paper describes the development and performance of a new rapid amperometric biosensor for fructose monitoring in food analysis. The biosensor is based on the activity of fructose dehydrogenase (FDH) immobilised into a carbon nanotube paste electrode according to two different procedures. The direct wiring of the FDH in a highly original osmium-polymer hydrogel was found to offer a better enzyme entrapment compared to the immobilisation of the enzyme in an albumin hydrogel. The optimised biosensor required only 5 U of FDH and kept the 80% of its initial sensitivity after 4 months. During this time, the biosensor showed a detection limit for fructose of 1 μM, a large linear range between 0.1 and 5 mM, a high sensitivity (1.95 μA cm−2 mM), good reproducibility (RSD = 2.1%) and a fast response time (4 s).  相似文献   
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In the search for non-chemical and green methods to counteract the bacterial contamination of foods, the use of natural substances with antimicrobial properties and light irradiation at proper light waves has been extensively investigated. In particular, the combination of both techniques, called photodynamic inactivation (PDI), is based on the fact that some natural substances act as photosensitizers, i.e., produce bioactive effects under irradiation. Notably, curcumin is a potent natural antibacterial and effective photosensitizer that is able to induce photodynamic activation in the visible light range (specifically for blue light). Some practical applications have been investigated with particular reference to food preservation from bacterial contaminants.  相似文献   
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