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181.
Natural events impacting on chemical and process plants may cause severe accidents, triggering the release of relevant quantities of hazardous substances. The present study focused on the development of the tools needed to build up a general framework allowing the extension of quantitative risk assessment procedure to include the analysis of the industrial accidents caused by natural events. Specific methods and models were developed to allow the quantitative assessment of risk caused by two categories of “Na-Tech” accidents: accidents triggered by earthquakes and accidents triggered by floods. The approach allows the identification of the different damage modes expected for process equipment and of the accidental scenarios that may be triggered. The damage models developed allow the calculation of the damage probability of equipment items due to the natural events. A specific methodology was issued to take into account the consequences of the possible contemporary failure of several process units due to the impact of the natural event. The procedure allows the calculation of the overall individual and societal risk indexes including the multiple-failure scenarios caused by the impact of natural events. The overall methodology was applied to the analysis of specific case studies.  相似文献   
182.
The present study reports for the first time qualitative and quantitative data about flavonoids and furocoumarins distribution of unripe Citrus × myrtifolia Rafinesque homogenate, used as ingredient of the popular soft drink Chinotto. No data are available in literature about the chemical characterization of flavonoids and furocoumarins of the chinotto homogenate used to produce the industrial extract. Samples for analysis were therefore processed to better reproduce the crude materials used to obtain industrial chinotto extract: the whole fruits were cut in half, seeds removed, softly squeezed discarding part of the juice, and homogenized in small pieces. The polyphenolics separation was made by HPLC–PDA detector coupled to ESI/MS/MS in positive and negative mode. It has allowed the identification and relative quantification of 16 compounds, among which the flavone-C-glycoside lucenin-2, the 3-hydroxy-3-methylglutaryl flavanone glycoside melitidin and five polymethoxylated flavones have been detected for the first time in Citrus × myrtifolia. The flavonoids and furocoumarins distribution was compared with one of the Citrus × myrtifolia juice, and the antioxidant activity of both samples was assessed by ORAC (Oxygen Radical Absorbance Capacity)-fluorescein assay.  相似文献   
183.
In the frame of an Interreg IIIC Network-Operation named RegEnergy, that unites 18 partners from 11 countries of Europe, the feasibility of using the woody by-products for heating purpose in a typical Mediterranean region was investigated. Focusing on the Abruzzo Region as representative sample area, it came out that a significant amount of the above mentioned renewable energetic material is annually available as a consequence of well-consolidated and economically significant agro-industrial activities, forest maintenance and industrial wood production and transformation. In particular, it was found that the total amount of woody residues, as dry substance, are more than 700 kt/a, with 30% resulting from pruning activities related to the cultivation of about 360 km2 of vineyards and 450 km2 of olive-groves; these residues are concentrated in the hilly part of the region close to the Adriatic sea coast. Starting by this pleasant situation, the feasibility of a properly localized wood pellets production plant was supported by both the economic and energetic analysis. Additional suggestions related to optimal plant localization and to the best use of the woody pellets as substitute of natural gas for heating purposes were reported along with the positive impact of the whole action on the quality of the environment and on the recovery of soil fertility.  相似文献   
184.
185.
    
In this article, an algorithm able to deal at the same time with wire frame and surface patch models for the method of moments in time domain is presented. After a unified theory combining both models, attention is focused on stability dependence issues on the time basis function chosen and on other algorithm parameters. An accurate analysis of time interpolation functions and of their time filtering properties is provided. © 2011 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2011.  相似文献   
186.
    
A domain decomposition approach is here applied to the finite element solution of a multiport waveguide passive device. The approach allows separating the problem in multiple, coupled subproblems which can be solved individually. By appropriately defining one of these subdomains as containing all the possible variations to be studied it is hence possible to restrict the tolerance analysis to this latter, smaller domain. Numerical results showing the gain in computing time are presented. © 2008 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2009.  相似文献   
187.
    
Polymorphic crystalline microfibers from an achiral octithiophene with one S‐hexyl substituent per ring are separately and reproducibly grown with the same characteristics on various solid surfaces, including the interdigitated electrodes/SiO2 surface of a bottomcontact field‐effect transistor. The arrangement of the same molecule in two diverse supramolecular structures leads to markedly different electronic, optical, and charge mobility properties. The microfibers—straight and yellow emitting or helical and red emitting—exhibit p‐type charge transport characteristics, with the yellow ones showing a charge mobility and on/off current ratio of one and three orders of magnitude, respectively, greater than the red ones. Both forms show circular dichroism signals with significant differences from one form to the other. DFT calculations show that the octithiophene exists in two different quasi‐equienergetic conformations aggregating with diverse orientations of the substituents. This result suggests that the observed polymorphism is conformational in nature. The self‐assembly, driven by sulfur–sulfur non‐bonding interactions, amplifies the small property differences between conformers, leading to quite different bulk properties.  相似文献   
188.
  总被引:1,自引:0,他引:1  
A robust multivariate statistical procedure applied to an accurate gas chromatography (GC) analysis was used to analyze 1004 monovarietal and multivarietal Sicilian extra virgin olive oils coming from 22 cultivars of different geographical areas of Sicily and collected in nine years (1993, 1995, 1996, 1997, 1998, 1999, 2000, 2001 and 2002). The effect of the cultivar, of pedoclimatic conditions as well as of the year of harvesting on the olive oil fatty acid composition and therefore on their classification was investigated. Oleic, linoleic and palmitic fatty acids, important for the nutritional properties of an olive oil, showed a crucial rule in the characterization of olive oils.  相似文献   
189.
    
This monograph is a critical review of the biological activities that occur during virgin olive oil (VOO) extraction process. Strategic choices of plant engineering systems and of processing technologies should be made to condition the enzymatic activities, in order to modulate the nutritional and the sensory quality of the product toward the consumer expectations. “Modulation” of the product quality properties has the main aim to predetermine the quantity and the quality of 2 classes of substances: polyphenols and volatile compounds responsible of VOO nutritional and sensory characteristics. In the 1st section, a systematic analysis of the literature has been carried out to investigate the main olive enzymatic activities involved in the complex biotransformation that occurs during the mechanical extraction process. In the 2nd section, a critical and interpretative discussion of the influence of each step of the extraction process on the polyphenols and the volatile compounds has been performed. The effect of the different mechanical devices that are part of the extraction process is analyzed and recommendations, strategies, and possible avenues for future researches are suggested.  相似文献   
190.
  总被引:1,自引:0,他引:1  
ABSTRACT: The major natural polyphenols of wine are flavonoids. Red wine also contains a natural phytoalexin called resveratrol which recently has been the subject of conflicting reports regarding its protective role against cardiovascular diseases. We have investigated the free radical scavenging capacity of resveratrol, its effects on xanthine oxidase (XO) activity, spontaneous membrane lipid oxidation, and DNA cleavage. Resveratrol showed a dose-dependent free radical scavenging activity, significant inhibition of XO activity, an anti-lipoperoxidative capacity, and a protective effect on DNA cleavage. The antioxidant capacity of resveratrol is ascribed to the concomitant activities of scavenging free radicals, metal chelating, and inhibition of some enzymes involved in free radical generation.  相似文献   
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