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161.
Calefato Fabio Castellano Giovanna Rossano Veronica 《Multimedia Tools and Applications》2019,78(23):33169-33188
Multimedia Tools and Applications - Revision control is a vital component in the collaborative development of artifacts such as software code and multimedia. While revision control has been widely... 相似文献
162.
Thermal behavior of thermoplastic polymer nanocomposites containing graphene nanoplatelets
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Andrea Caradonna Giovanna Colucci Mauro Giorcelli Alberto Frache Claudio Badini 《应用聚合物科学杂志》2017,134(20)
Polypropylene (PP), acrylonitrile butadiene styrene (ABS), and thermoplastic polyurethane (TPU) nanocomposites filled with 5 wt % of two different kinds of commercially available graphene nanoplatelets (GNPs) were prepared. Composites materials were characterized in terms of thermal properties (thermal conductivity and thermal stability) in order to study the effect of different fillers within different thermoplastic matrices. The exfoliation process and the mechanical properties were also investigated. We chose three different thermoplastic polymers (polyolefin, copolymer and elastomer) to cover a wide range of thermoplastic materials and identify a guideline in the use of GNPs for nanocomposite materials. No drastic differences were observed in terms of mechanical properties when the same matrices were filled with different GNPs. Concerning thermal conductivity, it was observed that the GNPs plane dimensions play a crucial role in the increase of conductive properties. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44814. 相似文献
163.
Federica Prinetto Giovanna Ghiotti Sergio De Rossi Gaetano Di Modica 《Applied catalysis. B, Environmental》1997,14(3-4):225-239
Catalysts at different Cr loading (x, in the range 0.18–3.8 wt% Cr) were prepared by (i) impregnation of SiO2 Aerosil directly with the waste water (SCx(I) samples); or (ii) mixing Aerosil with chromium oxo-hydroxides, precipitated from the waste water to eliminate the sulphate and sodium ions (SCx(II) and SCx(III) samples). Preparations (II) and (III) only differ for the accuracy in sulphate and sodium ions elimination. Catalyst surface characterization was performed by FT-IR spectroscopy using CO, adsorbed at room temperature, as test molecule, and by UV-Vis-NIR DR spectroscopy. Their activity towards ethylene polymerization were tested by FT-IR spectroscopy, monitoring the time dependence of the CH2 stretching modes intensity. The obtained results were compared with those obtained for simplified Phillips catalysts with comparable chromium contents, SCx(R). SCx(I) catalysts were not active in the ethylene polymerization, while the SCx(II) and SCx(III) ones showed lower activity (1/10 at maximum) compared to that of simplified Phillips catalysts with comparable chromium contents. SCx(II) and SCx(III) catalysts were active in the isobutane dehydrogenation reaction and showed activity in the range of those of standard catalysts, while SCx(I) ones showed activity at 873 K, but very low at the usual temperatures (773–823 K). 相似文献
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165.
Valente G Martelli S Taddei F Farinella G Viceconti M 《Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine》2012,226(2):161-169
Modelling the mechanical effect of muscles is important in several research and clinical contexts. However, few studies have investigated the effect of different muscle discretizations from a mechanical standpoint. The present study evaluated the errors of a reduced discretization of the lower-limb muscles in reproducing the muscle loading transferred to bones. Skeletal geometries and a muscle data collection were derived from clinical images and dissection studies of two cadaver specimens. The guidelines of a general method previously proposed for a different anatomical district were followed. The data collection was used to calculate the mechanical effect of muscles, i.e. the generalized force vectors, and the errors between a large and a reduced discretization, in a reference skeletal pose and in the extreme poses of the range of motion of joints. The results showed that the errors committed using a reduced representation of muscles could be significant and higher than those reported for a different anatomical region. In particular, the calculated errors were found to be dependent on the individual anatomy and on the skeletal pose. Since different biomechanical applications may require different discretization levels, care is suggested in identifying the number of muscle lines of action to be used in musculoskeletal models. 相似文献
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The modern low-pressure methanol synthesis catalysts are based on copper-containing systems such as Cu/ZnO/Al2O3 and Cu/ZnO/Cr2O3 with various compositions. These catalysts are also highly active for the low-temperature CO shift reaction. For both reactions the nature of the active sites is still an open question. 相似文献
168.
Regina Frei Richard McWilliam Benjamin Derrick Alan Purvis Asutosh Tiwari Giovanna Di Marzo Serugendo 《The International Journal of Advanced Manufacturing Technology》2013,69(5-8):1033-1061
This article reviews the existing work in self-healing and self-repairing technologies, including work in software engineering, materials, mechanics, electronics, MEMS, self-reconfigurable robotics, and others. It suggests a terminology and taxonomy for self-healing and self-repair, and discusses the various related types of other self-* properties. The mechanisms and methods leading to self-healing are reviewed, and common elements across disciplines are identified. 相似文献
169.
D. Melideo D. Baraldi B. Acosta-Iborra R. Ortiz Cebolla P. Moretto 《International Journal of Hydrogen Energy》2017,42(11):7304-7313
During the filling of hydrogen tanks high temperatures can be generated inside the vessel because of the gas compression while during the emptying low temperatures can be reached because of the gas expansion. The design temperature range goes from ?40 °C to 85 °C. Temperatures outside that range could affect the mechanical properties of the tank materials. CFD analyses of the filling and emptying processes have been performed in the HyTransfer project. To assess the accuracy of the CFD model the simulation results have been compared with new experimental data for different filling and emptying strategies. The comparison between experiments and simulations is shown for the temperatures of the gas inside the tank, for the temperatures at the interface between the liner and the composite material, and for the temperatures on the external surface of the vessel. 相似文献
170.