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61.
Piero Zamperoni 《Image and vision computing》1984,2(3):123-133
A model-based approach to grey-tone image segmentation is presented. A conceptual and computational frame is described, in which a variety of image models can be accommodated. Each model is defined by a feature pair and implies a uniformity criterion for ideal regions. Some particularly relevant models are described in detail and illustrated by means of experimental results obtained with real-world images. 相似文献
62.
Colli Franzone Piero Stefanelli Mario Viganotti Carlo 《IEEE transactions on bio-medical engineering》1979,(10):586-596
The use of mathematical models of iron metabolism has been recognized as an essential tool for analyzing ferrokinetic data. Multicompartment models, however, did not make it possible to describe marrow iron kinetics, taking into account that marrow erythroid cells uptake iron from the plasma according to their maturity. 相似文献
63.
Ermanno Barni Piero Savarino Gaetano di Modica Rosarina Carpignano Sisto Sergio Papa Giacomo Giraudo 《Dyes and Pigments》1984,5(1):15-36
Data on a series of 65 azo dyes derived from 4-alkylamido-2-hydroxybenzoic acids are reported. The dyes are suitable for application to polyamide fibres.Many correlations between the nature of substituents and the physical, spectroscopic or tinctorial properties of dyes were established. Correlations between structure and colour of dyed fabrics were also found. 相似文献
64.
Raffaello Lazzaroni Sergio Bertozzi Carlo Bertucci Piero Salvadori Piero Pino 《Israel journal of chemistry》1976,15(1-2):63-68
A series of cis- and trans-dichloro(benzylamine) (chiral olefin) platinum(II) complexes, containing (Z) and (E) isomers of the internal chiral olefins R-CH=CH-R', has been prepared by ethylene displacement from the corresponding ethylene containing complexes. The particular stereochemical features of the complexes allow one to interpret the CD on the basis of the individual contributions coming from the chiral centres already present in the free olefin and from the chiral centres formed in the complexation of the double bond. Evidence is reported showing that the aforementioned contributions are additive and that the chiral centre(s) bound to the metal dominates the CD at about 400 nm, its chirality type being reflected in the sign and its chirality prevalence in the Δϵ value. 相似文献
65.
This study evaluates the performance of two nanofiltration membranes in removing a herbicide: dichloroaniline. The membranes, one polyamide and one cellulose acetate, have a cut-off in the range 150-300 g/mol (manufacturers' data). The experiments were carried out with solutions of dichloroaniline in demineralized water, with concentrations from 1 to 10 ppb. For each membrane, the amount of herbicide retained and adsorbed by the membrane was determined as a function of feed concentration and transmembrane pressure. The two membranes, made of different materials but having the same nominal cut-off, retained dichloroaniline to very different extents and by different mechanisms. 相似文献
66.
67.
Andrea Baschirotto Enrico Dallago Massimo Ferri Piero Malcovati Andrea Rossini Giuseppe Venchi 《Measurement》2010
In this paper we present an Earth magnetic field measurement system and an automated acquisition setup to characterize it. The measurement system consists of a fluxgate sensor and an integrated front-end circuit, both realized in CMOS technology. The couple of orthogonal axes of the sensor makes the system suitable for realizing an electronic compass device. Indeed, we can measure not only the amplitude of the Earth magnetic field (whose full-scale value is of the order of 60 μT), but also its direction. The complete measurement system achieves a maximum angular error of 1.5° in the measurement of the Earth magnetic field direction. Furthermore, an acquisition setup was developed to evaluate the measurement system performance. It consists of a precision mechanical plastic structure, in tower form, a microcontroller-based interface circuit, that provides a digital output through an RS232 serial interface, a PC software suitably developed to post-process the data from the acquisition system and a couple of Helmholtz coils to evaluate the linearity of the system. This setup allows us to perform a completely automated and numerically controlled characterization of the measurement system. 相似文献
68.
Gian Piero Gallerano Andrea Doria Marzia Germini Emilio Giovenale Giovanni Messina Ivan P. Spassovsky 《Journal of Infrared, Millimeter and Terahertz Waves》2009,30(12):1351-1361
Two Free Electron Laser sources have been developed at ENEA-Frascati for a variety of applications: A Compact Free Electron
Laser (C-FEL) that provides coherent radiation in the frequency range between 90 and 150 GHz Gallerano et al. (Infrared Phys. and Techn. 40:161, 1999), and a second source, FEL-CATS, which utilizes a peculiar radio-frequency structure to generate coherent emission in the
range 0.4 to 0.7 THz Doria et al. (Phys. Rev. Lett 93:264801, 2004). The high peak power of several kW in 15 to 50 ps pulses, makes these sources particularly suitable for the assessment of
exposure limits in biological systems and for long range detection. In this paper we present a phase-sensitive reflective
imaging device in the mm-wave and THz regions, which has proven to be a valuable tool in the biological Ramundo-Orlando et al. (Bioelectromagnetics 28:587–598, 2007), environmental Doria et al. (2005) and art conservation fields Gallerano et al. (2008). Different setups have been tested at different levels of spatial resolution to image objects from a few centimeter square
to larger sizes. Images have been compared to identify and characterize the contrast mechanism. 相似文献
69.
Differential scanning calorimetry (DSC) and inelastic neutron scattering were applied to study the phase separation kinetics of Maya asphaltene water-in-oil emulsion by following the water separation from the upper phase. In addition, transformation of the separated water from the free state to the bound and/or restricted state was also investigated. Maya asphaltene in toluene with 0.1 M HCl forms emulsion following ultrasonic or high speed mechanical emulsification. Initially, water molecules in the emulsion are largely free water. The emulsion gradually separates into two phases and at the 7th day over 90% of water molecules have situated at the bottom phase. In the mean time water molecules at the free state initially slowly transform into bound state in a much slower pace (over 100 days) than the phase separation kinetics. 相似文献
70.
Alessandro Mandoli Marco Lessi Dario Pini Claudio Evangelisti Piero Salvadori 《Advanced Synthesis \u0026amp; Catalysis》2008,350(3):375-379
The use of platinum‐catalyzed hydrosilylation chemistry of silicones greatly simplifies the preparation of bis‐oxazoline (box) ligands covalently bound to an insoluble polymeric support. The use of such immobilized chiral ligands in different copper‐catalyzed asymmetric transformations (carbonyl‐ene, Mukaiyama aldol and olefin cyclopropanation reactions) allows the attainment of high levels of enantioselectivity (91–99 % ee). 相似文献