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101.
102.
Luciano Favretto Luciana Gabrielli Favretto 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1984,179(5):377-380
Summary Principal component analysis has been applied to analyze the correlation matrix obtained from a (6 × 44) data matrix. The 6 trace metals are Co, Ni, Cu, Cd, Hg, and Pb, which are contained in the soft part of edible mussels (Mytilus galloprovincialis Lamarck) from a hatchery on the gulf of Trieste. In the space of eigenvectors, the dimensions are reduced to 3 principal axes, which account for about 77% of the total variance.The unrotated factor matrix obtained by the principal components shows that Co, Ni and Cu are bonded to the first principal component, Cd and Pb to the second, Hg to the third. This picture is also assessed by the Varimax-rotated matrix and it is tentatively explained, at least in part, by considering the associations of the trace metals from various geographical sources.
Hauptkomponentenanalyse für das Studium der Assoziationen unter Spurenmetallen in Miesmuscheln im Golf von Triest
Zusammenfassung Die Hauptkomponentenanalyse wurde auf die Korrelationsmatrix, die aus der (6 × 44) Datenmatrix hervorgeht, angewandt. Die 6 Spurenmetalle sind Co, Ni, Cu, Cd, Hg, Pb, die im Miesmuschelnfleisch (Mytilus galloprovineialis Lamarck) gefunden werden. Die Miesmuschelnproben stammen aus der Zucht des Golfes von Triest. In dem Eigenvektorraum werden die Dimensionen auf drei Hauptachsen reduziert, die ungefähr 77% der totalen Varianz erklären.Die unrotierte Faktorenmatrix, die aus den Hauptkomponenten hervorgeht, zeigt, daß Co, Ni, Cu an die erste Hauptkomponente, Cd und Pb an die zweite, Hg an die dritte gebunden sind. Dieses Bild wird von der Varimax-rotierten Matrix bestätigt und es findet eine Erklärung in der Herkunft der Spurenmetalle.相似文献
103.
Thaísa Leal da Silva Luciano Volcan Agostini Luis Alberto da Silva Cruz 《Journal of Real-Time Image Processing》2016,12(2):357-368
The advances in display technologies and the growing popularity of 3D video systems have attracted more consumers for 3D viewing experiences, and, consequently, the demand for storage and transmission of 3D video content is increasing. To cope with this demand, a 3D video extension of high-efficiency video coding (HEVC) standard is being developed and near the final standardization stage. The upcoming 3D-HEVC standard is expected to provide higher encoding efficiency than its predecessors, supporting multiple views with high resolution, at a cost of considerable increase in computational complexity, which can be an obstacle to its use in real-time applications. This article proposes a novel complexity reduction algorithm developed to optimize the 3D-HEVC intra mode decision targeting real-time video processing for consumer devices with limited computational power, such as 3D camcorders and smartphones equipped with multiple cameras and depth acquisition capabilities. The proposed algorithm analyzes the texture frames and depth maps to estimate the orientation of edges present in the prediction unit data, speeding up the intra prediction process and reducing the 3D-HEVC encoding processing time. Experimental results demonstrate that the proposed algorithm can save 26 % in computational complexity on average with negligible loss of encoding efficiency. This solution contributes to make more feasible the compression of 3D videos targeting real-time applications in power-constrained devices. 相似文献
104.
105.
Nasim Mia Kuljeet Singh James Polson Luciano Lisi Evan Willemsen Yulin Hu 《加拿大化工杂志》2024,102(2):585-606
Hydrogen (H2) is a clean energy carrier widely used in oil refineries, fertilizers, chemicals, and steel manufacturing. Presently, the majority of H2 is produced from either steam methane reforming of natural gas or coal gasification; however, these technologies result in a massive amount of CO2 emission. Alternatively, the use of photocatalysts for producing H2 via water splitting is an eco-friendly and sustainable approach, among which the selection of highly efficient, stable, and cheap photocatalysts is the key. In this review, Znln2S4-based photocatalysts are thoroughly described in terms of the fundamentals and thermodynamics of water splitting, fabrication methods, and different heterostructure photocatalytic systems. After this, recent developments in the large-scale implementation of photocatalytic reactors are discussed. Finally, a summary of future research directions and major conclusions is provided. With proper modification, such as heterojunction systems and the selection of proper fabrication methods, Znln2S4-based photocatalysts could be superior materials for water splitting. In short, this review article could offer meaningful and useful insights and guidance for the development of Znln2S4-based photocatalysts in water splitting for producing H2 under visible light. 相似文献
106.
Alberto Angioni Luciano Porcu Marco Secci Pierantonio Addis 《Food Analytical Methods》2012,5(5):1131-1136
Sea urchin roe (Paracentrotus lividus) is an excellent biomarker, and it has been used as a test for toxicology study of chemical pollution of restricted marine
areas; in fact, unlike mussels which filter water, it feeds mainly on micro- and macroalgae. Therefore, it is not influenced
by the sea tide and meets better the situation of local pollution. A modified Quick Easy Cheap Effective Rugged Safe extraction
method coupled with gas chromatography ion trap mass spectrometry analysis has been used to set up a method for the determination
of 17 polycyclic aromatic hydrocarbons (PAHs) in P. lividus sea urchin roe. A method validation was performed, and the following parameters have been determined: instrument limit of
detection (LOD) and of quantification (LOQ), precision, recovery, and linearity. The method carried out showed good LOD under
1.5 μg/kg and LOQ under 5 μg/kg for all PAHs studied, and these values were in close agreement with quality criteria described
in the Commission Regulation (EC) no. 333/2007 concerning the PAH benzo[a]pyrene in foodstuffs. Precision and linearity were in accordance with EC SANCO/10684/2009 values. For all PAHs, recoveries
ranged from 72% to 119%, with RSD ranging from 3% to 17% in the most unfavorable case. 相似文献
107.
Eduardo Sáenz-de-Cabezón L. Javier HernándezM. Teresa Rivas Esteban García-RuizVicente Marco Ignacio Pérez-MorenoF. Javier Sáenz-de-Cabezón 《Mathematics and computers in simulation》2011,82(1):2-14
This paper presents a new procedure to construct families of spatial approximation-prediction functions which depend on several parameters. The method is based on partitions of the unity. In order to find optimal functions in these families we introduce a Vietoris simplicial set associated to an influence radius. We consider error estimators induced by these Vietoris simplicial sets. A computational implementation of these mathematical models has been developed to be applied to any kind of finite discrete data. Our methods provide a useful tool for the analysis of the spatial distribution of species, which is imperative for developing accurate and efficient management of endangered and invasive species, biological conservation programs, etc. We demonstrate the application of our method to the analysis of the spatial distribution of the grape moth Lobesia botrana (Lepidoptera: Tortricidae) in the vineyards of La Rioja obtaining useful results for the management of this pest. 相似文献
108.
Véronic Landry Pierre Blanchet Luciano Zotig Tommy Martel 《Journal of Coatings Technology and Research》2013,10(1):37-46
The purpose of this study was to investigate the performance of a semitransparent PVDF–acrylic coating on two wood species: Black spruce and White pine. An accelerated aging test was performed on the PVDF–acrylic coating and the results obtained were compared with those obtained for a water-based acrylic coating. Color changes were found to be more significant for the acrylic coating, especially after 1000 h of exposure, and for the White pine panels. Infrared spectroscopy revealed that the acrylic resin was more affected by the accelerated aging test than the PVDF resin, although X-ray photoelectron spectroscopy revealed that PVDF was slightly affected at the extreme surface (first 10 nm). Star-shaped defects were found at the surface of the White pine panels finished with the PVDF–acrylic coating. Experiments revealed that the PVDF–acrylic coating does not seem to be flexible enough to sustain resin exudation or other stresses. 相似文献
109.
110.
José Robinson-Duggon Francisco Pérez-Mora Luciano Dibona-Villanueva Denis Fuentealba 《Israel journal of chemistry》2018,58(3-4):199-214
Cucurbit[n]urils (CB[n]s) have emerged as potential candidates for drug delivery in several areas due to their strong binding interactions and low toxicity. More recently, their benefits for a type of cancer treatment termed Photodynamic Therapy (PDT) have been recognized. The outcomes of this therapy rely on better drug delivery strategies and improving overall photoactivity of the drugs, which is where CB[n]s could have a strong impact. The effects of these molecular containers on photoactivity are discussed and new interesting work is highlighted. 相似文献