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11.
R. DellAnna P. Lazzeri M. Frisanco F. Monti F. Malvezzi Campeggi E. Gottardini M. Bersani 《Analytical and bioanalytical chemistry》2009,394(5):1443-1452
The discrimination and classification of allergy-relevant pollen was studied for the first time by mid-infrared Fourier transform
infrared (FT-IR) microspectroscopy together with unsupervised and supervised multivariate statistical methods. Pollen samples
of 11 different taxa were collected, whose outdoor air concentration during the flowering time is typically measured by aerobiological
monitoring networks. Unsupervised hierarchical cluster analysis provided valuable information about the reproducibility of
FT-IR spectra of the same taxon acquired either from one pollen grain in a 25 × 25 μm2 area or from a group of grains inside a 100 × 100 μm2 area. As regards the supervised learning method, best results were achieved using a K nearest neighbors classifier and the leave-one-out cross-validation procedure on the dataset composed of single pollen grain
spectra (overall accuracy 84%). FT-IR microspectroscopy is therefore a reliable method for discrimination and classification
of allergenic pollen. The limits of its practical application to the monitoring performed in the aerobiological stations were
also discussed.
Figure Traditional and innovative methods for the identification of airborne pollen grains 相似文献
12.
In this paper, we discuss some relations between zeros of Lucas–Lehmer polynomials and the Gray code. We study nested square roots of 2 applying a “binary code” that associates bits 0 and 1 to “plus” and “minus” signs in the nested form. This gives the possibility to obtain an ordering for the zeros of Lucas–Lehmer polynomials, which take the form of nested square roots of 2. 相似文献
13.
Djaoued Y. Badilescu S. Ashrit P.V. Bersani D. Lottici P.P. Robichaud J. 《Journal of Sol-Gel Science and Technology》2002,24(3):255-264
Nanocrystalline titania films were prepared by a complexing agent-assisted sol-gel dip-coating process. The effect of acetylacetone, diethanolamine and polyethylene glycol on the structure of the heat-treated titania films was examined by Raman and FTIR spectroscopy and X-ray diffraction. The effect the complexing agents have on the anatase to rutile phase transition during the heat treatment process is studied. The understanding of this effect is expected to enhance our capacity to tailor the composition and morphology of films and thus their properties. The Raman and the infrared spectra of nanocrystalline titania films and the changes induced by the heat treatment were also investigated. We have also studied the size of the crystallites in TiO2 films and its dependence on the type of complexing agent used. 相似文献
14.
M. L. Polignano M. Alessandri B. Crivelli R. Zonca A. P. Caricato M. Bersani M. Sbetti L. Vanzetti 《Journal of Non》2001,280(1-3):39-47
A newly developed technique for the simultaneous measurement of the oxide–silicon interface properties and of minority carrier lifetime in the silicon volume was used for a systematic study of the nitridation process of oxide films.This technique is based on the surface recombination velocity measurements, and does not require the formation of a capacitor structure, so it is suitable for the measurement of as-grown interface properties. Oxides grown both in dry and in wet environments were prepared, and nitridation processes in N2O and in NO were compared to N2 annealing processes. The effect of nitridation temperature and duration were also studied, and processes of rapid thermal oxidation (RTO) and nitridation (RTN) were compared to conventional furnace nitridation processes. Surface recombination velocity was correlated with nitrogen concentration at the oxide–silicon interface obtained by secondary ion mass spectroscopy (SIMS) measurements. Surface recombination velocity (hence surface state density) decreases with increasing nitrogen pile-up at the oxide–silicon interface, indicating that in nitrided interfaces surface state density is limited by nitridation. NO treatments are much more effective than N2O treatments in the formation of a nitrogen–rich interface layer and, as a consequence, in interface state reduction. X-ray photoelectron spectrometry (XPS) analyses were used to extend our correlation to very thin oxides (3 nm). 相似文献
15.
On Some Almost-Periodicity Problems in Various Metrics 总被引:1,自引:0,他引:1
The Bohr-type and the Bochner-type definitions for almost periodic functions are examined in various metrics (Stepanov, Weyl and Besicovitch). The correct definitions of Besicovitch-like multifunctions are given. Weak almost-periodic solutions are proved for differential equations and inclusions. This problem is also discussed as a fixed-point problem in function spaces. 相似文献
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Two holy water fonts (dated at the beginning of the XVII century) in the Santa Maria della Steccata Church in Parma (Italy) have recently been restored. Before the intervention, a detailed investigation on their degradation products was carried out to understand the mechanisms of alteration of the materials and to suggest appropriate restoration procedures.The analyses were performed by means of powder X-ray diffraction (XRD), micro-Fourier transform infrared (FTIR) and micro-Raman spectroscopies. Calcite, iron oxides, silicates and sodium chloride (from salted holy water) were found in the red coloured calcarenite. On and under the lead coverings, different lead oxides (mainly massicot), other lead salts (lead basic carbonate, cerussite, plumbonacrite Pb10O(OH)6(CO3)6 and lead-chlorine compounds as laurionite PbOHCl and phosgenite Pb2CO3Cl2) were identified by Raman spectroscopy and XRD. Haematite α-Fe2O3, goethite α-FeO(OH) and lepidocrocite γ-FeO(OH) were found on and around the iron hinges.Lead compounds and sodium chloride, through crystallization and solubilization cycles, were responsible for the stone's degradation, whereas the iron corrosion materials on the hinges produced mechanical stress and cracks in the stone.Various suggestions have been given on how to restore these fonts and to remove the causes of damage. 相似文献
18.
Alberto Maria Bersani Alessandro Della Corte Giuseppe Piccardo Nicola Luigi Rizzi 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2016,67(4):108
The authors investigate the linear vibrations induced in an elastic string by a loading point-like mass constrained to moving on it with constant horizontal velocity. Exact solutions are shown in the case of subsonic regime. The displacement is explicitly provided in terms of a power series determined by iteration, which is shown to converge to the solution of the problem. The presence of a discontinuity in the right extremum of the considered space interval is also shown both analytically and numerically. 相似文献
19.
C. Baratto P.P. Lottici D. Bersani G. Antonioli G. Gnappi A. Montenero 《Journal of Sol-Gel Science and Technology》1998,13(1-3):667-671
Films of Fe2O3 have been prepared by two different sol-gel syntheses, starting from inorganic salts as precursors, Fe(NO3)3 · 9H2O or FeCl3 · 6H2O. Differences in the local order between the two preparations are investigated by XAFS (X-Ray Absorption Fine Structure) and Raman measurements. 相似文献
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