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41.
Molybdenum octahedral clusters, when incorporated into an appropriate polymer matrix, are considered as promising agents for a range of biological applications. This work describes the one‐pot synthesis, morphology and cellular toxicity of nano‐sized polystyrene beads doped with luminescent cluster complexes [{Mo6X8}(NO3)6]2? (X = Cl, Br or I). Specifically, the particles were obtained by free radical dispersion copolymerisation of styrene and methacrylic acid or 4‐vinylpyridine in the presence of the cluster complexes. The effects of the cluster loading in the reaction mixture on both the content of the final material and number‐average molar mass of the copolymers were evaluated. © 2017 Society of Chemical Industry  相似文献   
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The paper presents the research activity developed by the authors in the field of computer-aided inventive problem solving: an original model and a dialogue-based software application have been developed by integrating the logic of ARIZ (Algorithm for the Inventive Problem Solving) with some OTSM-TRIZ (General Theory of Powerful Thinking) models in order to guide a user also with no TRIZ education to the analysis of inventive problems. The paper demonstrates that through a dialogue-based interaction it is possible to guide the user towards a proper formulation of the problem statement, which is an essential step of any conceptual design activity. The proposed software system, although still at a prototype stage, has been tested with students at Politecnico di Milano and at the University of Florence. The paper details the structure of the algorithm and the results of the first validation activity; then, it discusses about the possibility to integrate the proposed approach into a new generation of CAD systems.  相似文献   
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A comprehensive study of the mechanisms of heating and cooling originating from an electrical current in semiconductor devices is reported. The variation in temperature associated with the Peltier effect is not related to the presence of heat sources and sinks if the heat flux is correctly determined. The Thomson effect is commonly regarded as a heat source/sink proportional to the Thomson coefficient, which is added to the Joule heating. In the present work, we will show that this formulation of the Thomson effect is not sufficiently clear. When the heat flux is correctly defined, the Thomson heat source/sink is proportional to the Seebeck coefficient. In the conditions in which the Peltier effect takes place, the temperature gradient is created, and, consequently, the Thomson effect will occur naturally.  相似文献   
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Charge migration is a ubiquitous phenomenon with profound implications throughout many areas of chemistry, physics, biology, and materials science. The long-term vision of designing functional materials with tailored molecular-scale properties has triggered an increasing quest to identify prototypical systems where truly molecular conduction pathways play a fundamental role. Such pathways can be formed due to the molecular organization of various organic materials and are widely used to discuss electronic properties at the nanometer scale. Here, we present a computational methodology to study charge propagation in organic molecular stacks at nano and sub-nanoscales and exploit this methodology to demonstrate that moving charge carriers strongly affect the values of the physical quantities controlling their motion. The approach is also expected to find broad application in the field of charge migration in soft matter systems.  相似文献   
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The present article proposes a constitutive model that includes the stacking fault energy (SFE)-dependence of the deformation behavior of Fe-Mn-C-(Al) TWIP steels. The different kinetics of the SFE-dependent strain hardening of twinned and twin-free grains are accounted for. The high flow stress of TWIP steels investigated is attributed to the combined effect of a large fraction of twinned grains and a low dynamic recovery rate—both effects being associated with its lowest SFE.  相似文献   
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The equations of energy balance, heat balance, and diffusion heat balance are obtained for a bipolar semiconductor. The roles of nonequilibrium charge carriers and the recombination in the heat transport are established. The expressions for the sources of energy fluxes, heat fluxes, and diffusion heat fluxes are discussed. Both radiative and nonradiative recombinations are studied.  相似文献   
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