Search results for "engineering.material"
showing 10 items of 2352 documents
Claiming the sea: Bronze Age fortified sites of the north-eastern Adriatic Sea (Cres and Lošinj islands, Croatia)
2017
ABSTRACTMore than 1,000 Bronze and Iron Age hillforts can be listed for the eastern Adriatic region. These constructions left a mark on the landscape which is still perceptible today. In some cases, such as the island of Losinj, this density is challenging to explain: almost thirty hillfort (or simply hilltop) sites were recorded on a rugged island with an area of 74km2. Different factors potentially involved in the formation of this settlement pattern are discussed (territorial control, surveillance, control of maritime networks), only to show that without considering some kind of symbolic display a plausible explanatory model cannot be devised. A new reading of the coastal seascape is pro…
Seismic properties across an amphibolite- to greenschist-facies strain gradient (Neves area, eastern Alps, Italy): New considerations for shear zone …
2021
Abstract Detecting the presence and geometry of crustal shear zones by geophysical methods relies on our understanding of the intrinsic parameters controlling the seismic properties of these deformed rocks, over the range of pressure-temperature conditions expected in the Earth's crust. To this end, we aimed to track changes in P-wave propagation velocity (VP), anisotropy (AVP) and S-wave splitting (AVS) across a natural shear zone using experimental and electron backscatter diffraction methods. Five samples were collected across a meter-scale shear zone developed under amphibolite- to greenschist-facies in the Neves metagranodiorite (Tauern Window, Eastern Alps). With increasing strain, se…
Review of the SISAK system in transactinide research
1998
Abstract The performance of the SISAK 1 liquid–liquid extraction system applied in transactinide experiments has been improved with respect to the equipment itself and the way it is operated. The improvements were checked in on-line experiments, under conditions similar to those during transactinide experiments. As a result, the yield of the separation system was increased by a factor >5. Furthermore, a cleaner organic scintillation phase was obtained due to a better phase separation. This reduced the β-background, which disturbs the α-measurements. The sensitivity of the SISAK apparatus, including the gasjet and the detection system has been improved by more than one order of magnitude.
Phosphorylation triggered growth of metal phosphate on halloysite and sepiolite nanoparticles: preparation, entrapment in chitosan hydrogels and appl…
2020
The rational design of porous, biomass-derived eco-friendly adsorbents instead of costly synthetic, petroleum-based resins stands as a promising approach to resolving the thorny issue of sewage treatment (for example, by supplying safe water for drinking and irrigation). Herein we explore a straightforward transformation of abundant clay and polysaccharides into highly-reactive water-cleaning adsorbents. Surface-functionalization of sepiolite and halloysite by phosphoryl chloride triggered metal dissolution from the framework (inside of the lumen for halloysite and on the external surface for sepiolite) and the concomitant growth of well-truncated crystalline metal phosphates. These unprece…
Comparative statistical studies on the anthropology of the Iron Age (last millennium B.C.)
1975
Abstract Extending previous statistical studies on the anthropology of the Neolithic and Bronze Ages, anthropological material from the Iron Age (1000-0) was compiled and condensed into 71 series (population samples). Penrose distances were calculated on the basis of 10 skull measurements. The dendrogram consisting of 49 larger series shows a division into a west- and an east-cluster. The west-cluster can be broken down into a northern, entirely European section, and into a southern subcluster, stretching from Sardinia to Pakistan. The east-cluster differs from the west-cluster above all in the larger width measurements, as in the case with the north-east and south-west complexes in the Neo…
Distribution of radioactive elements in three progressively metamorphosed pelite series of the Bohemian Massif
1980
The variations of the content of radioactive elements in pelitic rocks in dependence on the grade of metamorphism were studied in three regions of the Bohemian Massif with a different character and age of metamorphism. The concentrations of Th, U and K were determined by gammaspectrometric method, the major elements Si, Ti, Al, Fe, Mn, Ca, K, P by the X-ray fluorescence method. An increasing mobility of radioactive elements was found with the help of variation diagrams in the higher stages of metamorphism, the migration being apparent especially for Th and usually starting in the garnet or biotite zone. A significant negative correlation of both Th and U content with the content of SiO2 was…
Qualitative traits and shelf life of fig fruit (cv Melanzana) treated with Aloe vera gel coating
2021
The fig (Ficus carica L.) cv Melanzana is typical of Southern Italy. This cultivar produces breba fruit in June and fig fruit in August. Some previous studies on the use of coatings extracted from stems of Aloe vera showed positive effects to maintain fruit quality during shelf life. However, there are no studies on breba fig fruit treated with Aloe vera coating. In this study breba fig fruit, cv Melanzana, was treated with an application of Aloe vera gel, sealed in macro-perforated bag and stored at 5°C for 10 days. The effect of application of the Aloe vera gel on the shelf-life of this fruit, and its quality attributes after application were evaluated measuring fresh weight, total solubl…
Effects of ocean acidification on the shells of four Mediterranean gastropod species near a CO2 seep
2017
Marine CO2seeps allow the study of the long-term effects of elevated pCO2(ocean acidification) on marine invertebrate biomineralization. We investigated the effects of ocean acidification on shell composition and structure in four ecologically important species of Mediterranean gastropods (two limpets, a top-shell snail, and a whelk). Individuals were sampled from three sites near a volcanic CO2seep off Vulcano Island, Italy. The three sites represented ambient (8.15 pH), moderate (8.03 pH) and low (7.73 pH) seawater mean pH. Shell mineralogy, microstructure, and mechanical strength were examined in all four species. We found that the calcite/aragonite ratio could vary and increased signifi…
The cork oak in the Mountains of Palermo (Italy): ecological insights from the south-eastern edge of its distribution range
2020
Abstract: The uneven presence of the cork oak (Quercus suber L.) within its distribution range is not only determined by its climatic requirements but also by specific edaphic needs. Although most of the natural populations thrive in acidic soils deriving from metamorphic or volcanic rock outcrops, some cork oak populations are found growing in soils deriving from calcareous bedrock, which are considered less suitable. We carried out a multidisciplinary investigation at the south eastern edge of the Q. suber distribution range (Mountains of Palermo, NW Sicily), including soil, floristic, and vegetation surveys, aimed at: (i) assessing the native or introduced origin of some peculiar cork oa…
Essential oils composition of two Sicilian cultivars of Opuntia ficus-indica (L.) Mill. (Cactaceae) fruits (prickly pear).
2013
The essential oils composition of the skin, pulp and seeds from fruits of two Sicilian cultivars of Opuntia ficus-indica (cv. Sanguigna and cv. Surfarina) has been obtained by hydrodistillation and the possible antioxidant, antimicrobial and semiochemical roles have been investigated comparing the data with those reported in the literature. The presence of antioxidants and antimicrobials found in this study increases the spectrum of compounds that have beneficial properties in O. ficus-indica. In addition, several compounds identified in this study have been reported to influence the behaviour of Ceratitis capitata, a phytophagous pest which causes severe damages to several crops including …