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The aim of this investigation is to define a model of an alternating current impedance response that can identify the state of health of a porous electrode due to the blocked diffusion effect. To identify and simulate different pore geometries, an analytical differential equations system was studied. Standard and low performance battery products were simulated by the model and validated with electrochemical impedance spectroscopy (EIS) experimental data. The correlation between pore structure geometries and the related battery efficiency is also addressed. This investigation may clarify the possible reasons for low performance batteries. Identifying the benchmark pore geometry, parameters may be useful for the battery producers to improve the efficiency of their products. Various recovery methods are also included in this investigation to disperse the build-up of lead sulphate crystal that limits the electrolysis process in the low performance batteries. 相似文献
174.
Margarita Evtiouguina Alessandro Gandini Carlos Pascoal Neto Naceur M Belgacem 《Polymer International》2001,50(10):1150-1155
The reaction of various polyols derived from the oxypropylation of cork with aliphatic and aromatic mono‐ and diisocyanates was studied in solution at room temperature. In all instances, good second‐order kinetics were observed and the corresponding rate constant determined. The reactivity of the aromatic isocyanate was found to be much higher than that of aliphatic counterparts. The ensuing urethanes and polyurethanes were characterised by FTIR and 1H NMR spectroscopy, DSC and sol/gel distribution. © 2001 Society of Chemical Industry 相似文献
175.
The literature dedicated to the analysis of the difference in research productivity between the sexes tends to agree in indicating
better performance for men. Through bibliometric examination of the entire population of research personnel working in the
scientific-technological disciplines of Italian university system, this study confirms the presence of significant differences
in productivity between men and women. The differences are, however, smaller than reported in a large part of the literature,
confirming an ongoing tendency towards decline, and are also seen as more noticeable for quantitative performance indicators
than other indicators. The gap between the sexes shows significant sectorial differences. In spite of the generally better
performance of men, there are scientific sectors in which the performance of women does not prove to be inferior. 相似文献
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Andrzej Banaszuk Vladimir A. Fonoberov Thomas A. Frewen Marin Kobilarov George Mathew Igor Mezic Alessandro Pinto Tuhin Sahai Harshad Sane Alberto Speranzon Amit SuranaAuthor vitae 《Annual Reviews in Control》2011,35(1):77-98
Development of robust dynamical systems and networks such as autonomous aircraft systems capable of accomplishing complex missions faces challenges due to the dynamically evolving uncertainties coming from model uncertainties, necessity to operate in a hostile cluttered urban environment, and the distributed and dynamic nature of the communication and computation resources. Model-based robust design is difficult because of the complexity of the hybrid dynamic models including continuous vehicle dynamics, the discrete models of computations and communications, and the size of the problem. We will overview recent advances in methodology and tools to model, analyze, and design robust autonomous aerospace systems operating in uncertain environment, with stress on efficient uncertainty quantification and robust design using the case studies of the mission including model-based target tracking and search, and trajectory planning in uncertain urban environment. To show that the methodology is generally applicable to uncertain dynamical systems, we will also show examples of application of the new methods to efficient uncertainty quantification of energy usage in buildings, and stability assessment of interconnected power networks. 相似文献
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Maurizio Martino Anna Paola Caricato Francesco Romano Tiziana Tunno Daniele Valerini Marco Anni M. Elisabetta Caruso Alessandro Romano Tiziano Verri 《Journal of Materials Science: Materials in Electronics》2009,20(Z1):435-440
We report on the deposition of soft matter thin films by Matrix Assisted Pulsed Laser Evaporation (MAPLE). In particular,
thin layers of biological material (Bovine Serum Albumin) and polymers (polyfluorene) for medical and optoelectronic applications,
were realized by laser irradiating a frozen solution containing a low amount of material diluted in a laser absorbing volatile
solvent. The depositions were carried out varying different parameters as solvent–solute concentration, solvent nature, laser
fluencies, etc. The optical, morphological, structural and spectroscopical properties were detected by means of different
analyses as FTIR, photoluminescence, AFM and SDS. 相似文献
180.
Alessandro Abbotto Erika Herrera Calderon Norberto Manfredi Claudio Maria Mari Chiara Marinzi Riccardo Ruffo 《Synthetic Metals》2011,161(9-10):763-769
Vinylene-linked donor–acceptor–donor semiconducting polymers have been prepared by electropolymerization of the new monomers 2,6-bis[(E)-2-(1-methylpyrrol-2-yl)vinyl]pyridine and 2,5-bis[(E)-2-(1-methylpyrrol-2-yl)vinyl]pyridine. The monomers, consisting of two pyrrole donor units and a central pyridine acceptor ring spaced by vinylene links, differ by the substitution pattern around the central pyridine core (2,6 vs. 2,5-substitution). The electropolymerization process is more efficient on the 2,5-derivative. The new polymers show reversible electrochemistry dominated by a strong charge trapping effect. Poly(2,5-bis[(E)-2-(1-methylpyrrol-2-yl)vinyl]pyridine) energy levels closely match those of design rules for optimized polymers in combination with fullerene derivatives in bulk heterojunction solar cells. 相似文献