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991.
Darja Lisjak Pertti LintunenArto Hujanen Tommi VarisGiovanni Bolelli Luca LusvarghiMarko Jagodi? Miha Drofenik 《Materials Letters》2011,65(3):534-536
Composite coatings from different volume ratios of hexaferrite (BaFe12O19 or SrFe12O19) and polyethylene were prepared, for the first time, with flame spraying. The hexaferrite phase retained its crystal structure and microstructure during the process, while the polyethylene melted and resolidified. The coatings showed magnetic hysteresis loops with high coercivities. The measured electromagnetic behaviour proved that the studied composite coatings would be suitable for electromagnetic wave absorbers in the U-band. 相似文献
992.
Scott M. Duke-Sylvester Luca Bolzoni Leslie A. Real 《Journal of the Royal Society Interface》2011,8(59):817-825
Models for infectious diseases usually assume a fixed demographic structure. Yet, a disease can spread over a region encountering different local demographic variations that may significantly alter local dynamics. Spatial heterogeneity in the resulting dynamics can lead to important differences in the design of surveillance and control strategies. We illustrate this by exploring the north–south gradient in the seasonal demography of raccoon rabies over the eastern USA. We find that the greater variance in the timing of spring births characteristic of southern populations can lead to the spatial synchronization of southern epidemics, while the narrow birth-pulse associated with northern populations can lead to an irregular patchwork of epidemics. These results indicate that surveillance in the southern states can be reduced relative to northern locations without loss of detection ability. This approach could yield significant savings in vaccination programmes. The importance of seasonality in many widely distributed diseases indicates that our findings will find applications beyond raccoon rabies. 相似文献
993.
发现并生存于巴塞罗那旧城(CiutatVella)中心的"新"圣卡泰里娜的市场,就像是聆听某个人有时为了让停顿的争论重新富有生气,引出其他视野,同时向周围的人求助而大声说出来的、活泼而充满好奇的想法。EMBT(恩里克·米拉耶和贝纳德塔·达格利阿布艾)1999年到2005年设计和建造的市场不仅仅是简单而漂亮的建筑,而且是一个微笑的问号,是为了城市及居民的深度思索,是静静地从一个阶段到另一个阶段中寻找过渡建筑的工程之一。 相似文献
994.
Characterisation of naturally fermented sausages produced in the North East of Italy 总被引:2,自引:0,他引:2
In the Friuli Venezia Giulia region, in the North East of Italy, a traditional fermented sausage is produced without the use of microbial starters. It is characterized at the end of the ripening period by accentuated acidity, slight sourness and elastic, semi-hard consistency. In this study, three fermentations, carried out in different seasons (winter, spring and summer) were followed analyzing the microbiological, physicochemical and sensory aspects of this product. The sausages were characterized by an important microbial activity of lactic acid bacteria and micro/staphylococci that resulted in a product with a final pH of about 5.6-5.7. An interesting aspect was the high number of fecal enterococci that can play an important role in the definition of the organoleptic profile of the final product. No Listeria monocytogenes, Salmonella spp. and Staphylococcus aureus were ever isolated from the raw materials or the fermented sausages during the maturation, underlining the safety of this product. The final water activity of the product was 0.91-0.92. One hundred and fifty lactic acid bacteria were isolated and identified by molecular methods to understand which species were more predominant in the product. Lactobacillus curvatus and Lactobacillus sakei were the most numerous (54 and 64 strains isolated, respectively) and they were the only species common to all three fermentations. A cluster analysis of the profiles obtained from these strains after RAPD-PCR highlighted a population distribution that was fermentation-specific. 相似文献
995.
Anna Lisa Piccinelli Attilio Veneziano Siro Passi Francesco De Simone Luca Rastrelli 《Food chemistry》2007,100(1):344-349
Cottonseeds are fed to high-producing dairy cows as a source of fat and highly-digestible fibre. Seven flavonol glycosides have been identified from whole cottonseed by-product. Their structures were established as quercetin 3-O-{β-d-apiofuranosyl-(1 → 2)-[α-l-rhamnopyranosyl-(1 → 6)]-β-d-glucopyranoside} (1), kaempferol 3-O-{β-d-apiofuranosyl-(1 → 2)-[α-l-rhamnopyranosyl-(1 → 6)]-β-d-glucopyranoside} (2), quercetin 3-O-[β-d-apiofuranosyl-(1 → 2)-β-d-glucopyranoside] (3), quercetin 3-O-β-d-glucopyranoside (4), kaempferol 3-O-[α-l-rhamnopyranosyl-(1 → 6)-β-d-glucopyranoside] (5), quercetin 3-O-[α-l-rhamnopyranosyl-(1 → 6)-β-d-glucopyranoside] (6), and kaempferol 3-O-α-l-rhamnopyranoside (7). Gallic acid (8) and 3,4-dihydroxybenzoic acid (9) were also found. All structures were elucidated by ESI-MS and NMR spectroscopic methods. Total polyphenols were assayed by the Folin–Ciocalteu method. 相似文献
996.
Serena Niro Alessandra Fratianni Patrizio Tremonte Elena Sorrentino Luca Tipaldi Gianfranco Panfili Raffaele Coppola 《Journal of dairy science》2014
This study assessed and compared the physicochemical, microbiological, and sensorial characteristics of Caciocavallo cheeses, made from cow milk and a mixture of cow with ewe or goat milk, during ripening. Different cheese-making trials were carried out on an industrial scale following the standard procedure of pasta filata cheeses, with some modifications. The percentage of the different added milk to cow milk influenced compositional and nutritional characteristics of the innovative products, leading to a satisfactory microbiological and sensorial quality. 相似文献
997.
Andrea Dorigato Alessandro Pegoretti Luca Fambri Miroslav Slouf Jan Kolarik 《应用聚合物科学杂志》2011,119(6):3393-3402
We prepared cycloolefin copolymer (COC)/fumed silica nanocomposites by melt compounding to study the effect of the filler dimensions (filler surface area) on the physical properties, with particular attention to their thermal, mechanical, and optical behaviors. Thermogravimetric analysis revealed a positive contribution of silica nanoparticles to the thermal degradation resistance of COC, as the decomposition temperature of the nanofilled samples increased by 40°C with respect to that of the unfilled matrix. Dynamic mechanical thermal analysis and quasi‐static tensile tests of the nanocomposites evidenced a slight stiffening effect, proportional to the nanofiller surface area, without any reduction in the fracture toughness. Creep resistance of the nanocomposites was increased by the addition of silica nanoparticles, especially when high‐surface‐area nanoparticles were used. The positive effect of the nanoparticles on the viscoelastic and fracture behavior was related to the uniform dispersion of silica aggregates in the matrix. Ultraviolet–visible spectrometry measurements evidenced that the original transparency of neat COC was practically maintained after the addition of silica nanoparticles. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
998.
Luca Ortolani Florent Houdellier Marc Monthioux Etienne Snoeck Vittorio Morandi 《Carbon》2011,(4):1423-1429
We used low-voltage transmission electron holography to probe surface electrostatic potentials in graphene membranes and carbon nanotubes, as the number of graphenes varies. Further, we measured the phase shift induced by an individual graphene, and mapped the phase shift variation throughout a whole few-graphene-crystal as a function of the local number of layers. We found a size/surface effect as the ratio between the surface and the total number of atoms increases for an individual nanotube or graphene membrane. This surface phase term can be related to a fine electrostatic potentials redistributions occurring at the outer layers in carbon nanotubes and graphene membranes. 相似文献
999.
The goal of this paper is introducing the citer-success-index (cs-index), i.e. an indicator that uses the number of different citers as a proxy for the impact of a generic set of papers. For each of the articles of interest, it is defined a comparison term—which represents the number of citers that, on average, an article published in a certain period and scientific field is expected to “infect”—to be compared with the actual number of citers of the article. Similarly to the recently proposed success-index (Franceschini et al. Scientometrics 92(3):621–6415, 2011), the cs-index allows to select a subset of “elite” papers. The cs-index is analyzed from a conceptual and empirical perspective. Special attention is devoted to the study of the link between the number of citers and cited authors relating to articles from different fields, and the possible correlation between the cs- and the success-index. Some advantages of the cs-index are that (i) it can be applied to multidisciplinary groups of papers, thanks to the field-normalization that it achieves at the level of individual paper and (ii) it is not significantly affected by self citers and recurrent citers. The main drawback is its computational complexity. 相似文献
1000.
Olivier?CarrazEmail author Christian?Siemes Luca?Massotti Roger?Haagmans Pierluigi?Silvestrin 《Microgravity science and technology》2014,26(3):139-145
We propose a concept for future space gravity missions using cold atom interferometers for measuring the diagonal elements of the gravity gradient tensor and the spacecraft angular velocity. The aim is to achieve better performance than previous space gravity missions due to a very low white noise spectral behavior and a very high common mode rejection, with the ultimate goals of determining the fine structures of the gravity field with higher accuracy than GOCE and detecting time-variable signals in the gravity field better than GRACE. 相似文献