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Abstract

The authors’ objective is to manage sulfur content in gasoline over a multi-product pipeline using data derived from a correlation study. Sulfur content is analyzed by ultraviolet fluorescence or monochromatic wavelength dispersive X-ray fluorescence spectrometry in three different sampling points by three laboratories. At the same time, this study evaluates the homogeneity between laboratories/methods and if the analytical results of data vary in different sampling points of the pipeline. By means of two-way analysis of variance with interaction, the results show that there are variations along the multi-product pipeline besides differences between methods and laboratories.  相似文献   
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Embracing renewable energy technology makes a lot of sense for the public sectors and schools as it meets the government sustainability goals and provides a financially viable means of achieving carbon savings while offering income potential. This study is aimed to quantify the achievable energy saving by spread use ofphotovoltaic systems on public building stock in the city of Rome. The installation of PV (photovoltaic) systems in the historic center depends on the feasibility conditions, generally more complex compared to the cases examined in the consolidated city, because they require compliance with the formal and aesthetic characteristics of the buildings, so the choice must be made between compatible components, which allow to minimize the transformation. The suburbs are characterized by large plane roofs in bad conditions and belonging to isolated buildings, so the useful surface, according to shading condition, offers a big potential for renewable technologies. The research provides an evaluation of maximum production of solar energy and the subsequent energy saving and reduction of greenhouse gasses, using parametric data, and an evaluation of the cost-effectiveness, with a rough calculation of return on investment.  相似文献   
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This paper presents a three-dimensional (3D) finite-element (FE) analysis of eddy current losses generated in the tank walls and yoke clamps of a three-phase 40 MV A power transformer. The time harmonic FE model is used to compute the magnetic leakage field in the case of a short circuit condition of the power transformer. Three cases are analyzed to study the impact of modeling tank walls and yoke clamp plates in FE context in estimation of their losses. The load loss test was carried out on an experimental transformer to validate the simulation.  相似文献   
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The bioactive form of vitamin D, 1,25-dihydroxyvitamin D (1,25D3), exerts immunomodulatory actions resulting in neuroprotective effects potentially useful against neurodegenerative and autoimmune diseases. In fact, vitamin D deficiency status has been correlated with painful manifestations associated with different pathological conditions. In this study, we have investigated the effects of vitamin D deficiency on microglia cells, as they represent the main immune cells responsible for early defense at central nervous system (CNS), including chronic pain states. For this purpose, we have employed a model of low vitamin D intake during gestation to evaluate possible changes in primary microglia cells obtained from postnatal day(P)2-3 pups. Afterwards, pain measurement and microglia morphological analysis in the spinal cord level and in brain regions involved in the integration of pain perception were performed in the parents subjected to vitamin D restriction. In cultured microglia, we detected a reactive—activated and proliferative—phenotype associated with intracellular reactive oxygen species (ROS) generation. Oxidative stress was closely correlated with the extent of DNA damage and increased β-galactosidase (B-gal) activity. Interestingly, the incubation with 25D3 or 1,25D3 or palmitoylethanolamide, an endogenous ligand of peroxisome proliferator-activated-receptor-alpha (PPAR-α), reduced most of these effects. Morphological analysis of ex-vivo microglia obtained from vitamin-D-deficient adult mice revealed an increased number of activated microglia in the spinal cord, while in the brain microglia appeared in a dystrophic phenotype. Remarkably, activated (spinal) or dystrophic (brain) microglia were detected in a prominent manner in females. Our data indicate that vitamin D deficiency produces profound modifications in microglia, suggesting a possible role of these cells in the sensorial dysfunctions associated with hypovitaminosis D.  相似文献   
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Several authors proposed to import in Natural Language (NL) semantics the ideas lying behind the well-known Skolem theorem, defined in First Order Logic. In these proposals, logical forms include referential (functional) terms, inserted as argument of Generalized Quantifiers. The referential terms have to be maximized with respect to the model where formulae are evaluated, in order to provide the proper truth conditions. This article presents two recent proposals belonging to this approach, i.e. Steedman (2007) [60] and Robaldo (2009) [50], and compares their way to incorporate the maximality requirement. The comparison highlights that the latter provides a more adequate and flexible management of the model theoretic interpretation of the formulae and the inferences that may be carried out starting from them.  相似文献   
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Studies on the phase constitution of annealed master ingots of the Au49Ag5.5Pd2.3Cu26.9Si16.3 alloy suggest that it is a quinary eutectic and revealed which phases solidify from the melt. The alloy has been amorphized in ribbon form. Ribbon crystallization has been studied in isothermal and continuous heating modes. From such experiments data on the mechanism and kinetics of crystallization have been obtained. Time–temperature–transformation and Continuous Heating Transformations plots for crystallization have been derived from thermal data.  相似文献   
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