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61.
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   
62.
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   
63.
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   
64.
65.
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   
66.
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   
67.
Francesca Ridi  Piero Baglioni 《Fuel》2009,88(2):319-4687
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   
68.
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   
69.
70.

With the recent availability of industry-grade, high-performing engines for video games production, researchers in different fields have been exploiting the advanced technologies offered by these artefacts to improve the quality of the interactive experiences they design. While these engines provide excellent and easy-to-use tools to design interfaces and complex rule-based systems to control the experience, there are some aspects of Human-Computer Interaction (HCI) research they do not support in the same way because of their original mission and related design patterns pointing at a different primary target audience. In particular, the more research in HCI evolves towards natural, socially engaging approaches, the more there is the need to rapidly design and deploy software architectures to support these new paradigms. Topics such as knowledge representation, probabilistic reasoning and voice synthesis demand space as possible instruments within this new ideal design environment. In this work, we propose a framework, named FANTASIA, designed to integrate a set of chosen modules (a graph database, a dialogue manager, a game engine and a voice synthesis engine) and support rapid design and implementation of interactive applications for HCI studies. We will present a number of different case studies to exemplify how the proposed tools can be deployed to develop very different kinds of interactive applications and we will discuss ongoing and future work to further extend the framework we propose.

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