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In Italy the use of the underground for non-military purposes is highly developed only in the excavation of tunnels, e.g. for road, railway, hydroelectrical projects, underground trains and services. Owing to the generally difficult geological conditions, large underground works have been slow to develop in Italy. This paper summarizes and illustrates both existing and designed large underground projects.  相似文献   
74.
Reports an error in the original article by B. Lakey et al (Journal of Personality & Social Psychology, 1996 [Jun], Vol 70(6), 1270–1280. On page 1274, the degrees of freedom for several of the terms were incorrectly reported. In addition, the first author's name in the reference citation for Gurung et al. (1994) on p. 1279 contained a typographical error. (The following abstract of this article originally appeared in record 1996-01769-014). The extent to which perceived social support reflects characteristics of the environment, the personality of the perceiver, and their interaction is unknown. This article shows how the methods of generalizability theory can be used to address these questions. When participants rate the same targets on the targets' supportiveness, generalizability theory provides methods for determining the extent to which support judgments are determined by effects due to targets (supporters), perceivers, and their interaction. In 3 studies, each source of variance made significant contributions to support judgments, with the Perceivers–Supporters interaction, characteristics of supporters, and biases of perceivers making the largest contributions, respectively. The implications for theoretical models of perceived support are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
75.
Ignition phenomena in self-propagating high-temperature synthesis (SHS) of Al–C–Ti system were studied. The experiments were performed in quasi-adiabatic conditions. A CO2 laser was used as external energy source and was set to the influence of Al content, laser power and particle sizes of powder on the ignition behavior. The results showed the combustion temperature depended strongly on Al content, laser power and particle sizes of Ti and C; but the particle size of Al had little effect on combustion temperature, at the same time, the effect of Al content on adiabatic combustion temperature, Tad, was calculated. According to the calculation result, adiabatic temperature decreased with the increasing of Al content.  相似文献   
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Among the several known fatty acid‐derived chemical signals, the endogenous ligands of cannabinoid receptors type‐1 and ‐2, two G‐protein‐coupled receptors involved in several aspects of mammalian physiology and pathology, are perhaps those the levels of which have proven to be most sensitive to the fatty acid composition of the diet. The two most studied such ligands, known as endocannabinoids, are N‐arachidonoyl‐ethanolamine and 2‐archidonoylglycerol, and are found in tissues together with other N‐acyl‐ethanolamines and 2‐acylglycerols, not all of which activate the cannabinoid receptors, although several of them do exhibit important pharmacological effects. In this review article, we describe literature data indicating that the tissue concentrations of the endocannabinoids and related signalling molecules, and hence the activity of the respective receptors, can be modulated by modifying the fatty acid composition of the diet, and particularly its content in long chain PUFAs or in long chain PUFA precursors. We also discuss the potential impact of these diet‐induced changes of endocannabinoid tone on three of the major pathological conditions in which cannabinoid receptors have been involved, that is metabolic dysfunctions, inflammation and affective disorders.  相似文献   
78.
The effect of mesoporous Co3O4, NiCo2O4 and NiO on the hydrogen sorption performance of MgH2 was investigated. These oxides were synthesized by multi-step nanocasting and introduced during the high-energy ball milling of MgH2 powder to act as catalysts. Hydrogen desorption on the as-milled powders was assessed upon heating the samples from room temperature to 400 °C. In all cases, the onset temperature for desorption was lowered by taking advantage of the introduced additives. The NiO-doped sample displayed the best response, the desorption rate being 7 times faster than in pure MgH2. Complementary kinetic studies on this particular sample revealed that the sorption activation energies were much lower (50 kJ/mol for absorption and 335 kJ/mol for desorption) than the corresponding ones for undoped MgH2 (57 kJ/mol for absorption and 345 kJ/mol for desorption), thus proving the catalytic activity of the mesoporous NiO oxide. Significantly, the X-ray powder diffraction (XRPD) patterns taken on the NiO-doped sample after discharging/charging cycles revealed that Mg could fully hydrogenate at the end of the charging process, while Mg metal was still detected in the undoped (pure) sample. Favored conditions for dissociative chemisorption of hydrogen could be ascribed to the formation of metallic Ni arising from complete or partial reduction of NiO, as observed in the XRPD patterns.  相似文献   
79.
BACKGROUND: Many leafy brassicas are widely used for ready‐to‐use salads. Broccoli raab (Brassica rapa L.), also called turnip top, or rapini, is extensively cultivated in southern Italy. The edible portion is made up of the green, immature inflorescences and the stem with its most tender leaves. Recently, interest in this crop has increased among European consumers; moreover, a substantial increase in consumption could come from the ready‐to‐use product. RESULTS: The effects of four different atmosphere compositions (air, 3% O2 in nitrogen, 3% O2 + 10% CO2 in air, and 10% CO2 in air) on quality attributes of ready‐to‐use broccoli raab were studied. Controlled atmosphere affected appearance, composition, respiration rate, weight loss, and presence of off‐odours. Storage of broccoli raab florets under low oxygen conditions delayed post‐cutting deterioration during storage at 5 °C and preserved appearance and typical odour, up to 17 days. Moreover, respiration rate as well as loss of green colour, chlorophyll and vitamin C were also slowed down in this condition. Finally, in this study no effect of controlled atmosphere storage was found on total phenols content and antioxidant activity. CONCLUSION: Results showed that cold storage in 3% O2 can be beneficial in order to maintain quality of ready‐to‐use, broccoli raab for up to 17 days. Copyright © 2010 Society of Chemical Industry  相似文献   
80.
Levels of PCBs, DDTs and BHCs were measured in sediments taken from the central Mediterranean. BHC was usually < 1 ng g?1; ΣDDT (sum of DDT, DDE and DDD) ranged from < 1 ng g?1 to 27.5 ng g?1; ΣPCBs generally ranged from ca. 1 ng g?1 to > 80 ng g?1, but exceptionally high values (130–457 ng g?1) were observed from stations within Augusta Harbor.  相似文献   
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