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111.
The effects of temperatures and volumetric expansion on the diffusion of fluids through solid polymers 下载免费PDF全文
Yiming Fan Antonio Gomez Serena Ferraro Brian Pinto Anastasia Muliana Valeria La Saponara 《应用聚合物科学杂志》2017,134(31)
This study examines moisture sorption behaviors of two glassy polymers, epoxy and vinylester, immersed in different fluids at two temperatures below the glass transition temperatures of the polymers. The main purpose of this study is to understand the effect of volume‐dependent temperatures and deformations on the diffusion process of solid polymers. Diffusivity coefficients are first determined by assuming the diffusion to follow the classical Fickian diffusion. In some cases, moisture sorption led to quite significant changes of volume, and the diffusion process cannot be well described by the Fickian diffusion. In such situation, the coupled deformation–diffusion model for linear elastic isotropic materials presented by Gurtin 1 is adopted, as a first approximation. This coupled deformation‐diffusion model reduces to a Fickian diffusion model when the coupling parameters are absent and the volume changes in the solid polymers during diffusion are negligible. A finite difference method is used in order to solve for the coupled deformation‐diffusion model. The model is used to predict the one‐dimensional moisture diffusion in thin plates and the multiaxial three‐dimensional moisture diffusion in dogbone specimens. The multiaxial diffusion in the dogbone specimens is used to validate the calibrated material parameters from the standard thin plate diffusion characterization. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45151. 相似文献
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Sonia Di Gaetano Luciano Pirone Ioannis Galdadas Serena Traboni Alfonso Iadonisi Emilia Pedone Michele Saviano Francesco Luigi Gervasio Domenica Capasso 《International journal of molecular sciences》2022,23(5)
Galectins are soluble β-D-galactoside-binding proteins whose implication in cancer progression and disease outcome makes them prominent targets for therapeutic intervention. In this frame, the development of small inhibitors that block selectively the activity of galectins represents an important strategy for cancer therapy which is, however, still relatively underdeveloped. To this end, we designed here a rationally and efficiently novel diglycosylated compound, characterized by a selenoglycoside bond and the presence of a lipophilic benzyl group at both saccharide residues. The relatively high binding affinity of the new compound to the carbohydrate recognition domain of two galectins, galectin 3 and galectin 9, its good antiproliferative and anti-migration activity towards melanoma cells, as well as its anti-angiogenesis properties, pave the way for its further development as an anticancer agent. 相似文献
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Serena Mirata Vanessa Almonti Dario Di Giuseppe Laura Fornasini Simona Raneri Stefania Vernazza Danilo Bersani Alessandro F. Gualtieri Anna Maria Bassi Sonia Scarfì 《International journal of molecular sciences》2022,23(5)
Alveolar macrophages are the first line of defence against detrimental inhaled stimuli. To date, no comparative data have been obtained on the inflammatory response induced by different carcinogenic mineral fibres in the three main macrophage phenotypes: M0 (non-activated), M1 (pro-inflammatory) and M2 (alternatively activated). To gain new insights into the different toxicity mechanisms of carcinogenic mineral fibres, the acute effects of fibrous erionite, crocidolite and chrysotile in the three phenotypes obtained by THP-1 monocyte differentiation were investigated. The three mineral fibres apparently act by different toxicity mechanisms. Crocidolite seems to exert its toxic effects mostly as a result of its biodurability, ROS and cytokine production and DNA damage. Chrysotile, due to its low biodurability, displays toxic effects related to the release of toxic metals and the production of ROS and cytokines. Other mechanisms are involved in explaining the toxicity of biodurable fibrous erionite, which induces lower ROS and toxic metal release but exhibits a cation-exchange capacity able to alter the intracellular homeostasis of important cations. Concerning the differences among the three macrophage phenotypes, similar behaviour in the production of pro-inflammatory mediators was observed. The M2 phenotype, although known as a cell type recruited to mitigate the inflammatory state, in the case of asbestos fibres and erionite, serves to support the process by supplying pro-inflammatory mediators. 相似文献
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The effects of thermal treatment on green table olives were evaluated as a method to control enzymatic browning, to minimise the microorganism presence and to extend their shelf-life. However this treatment is often responsible for colour alterations, development of off-flavours and unfavourable texture changes. Moreover, the effect of different re-use of the natural brine of fermentation with or without different treatments was investigated. Calcium treatment was suggested to maintain firmness. Firming effects obtained from heat treatment combined with calcium treatment have been attributed to heat-activated pectin methylesterase and/or to increased calcium diffusion into tissues at higher temperatures. The results derived from this study will help in designing new processes which can be applied in table olive industry. 相似文献
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Reduction of NO emissions in a turbojet combustor by direct water/steam injection: Numerical and experimental assessment 总被引:2,自引:0,他引:2
Ernesto Benini Sergio Pandolfo Serena Zoppellari 《Applied Thermal Engineering》2009,29(17-18):3506-3510
Numerical and experimental investigations are conducted to assess the benefits and drawbacks of both water (mist) and steam direct injection within the combustion chamber of a 200 N static thrust turbojet. For this purpose, a three-dimensional CFD model of the combustion process is implemented where pollutant emissions are calculated; in parallel, a test campaign on the turbojet at sea level static conditions is carried out. In both cases the refrigerant flow is injected directly into the combustor, outside the liner. The aim of the investigations is to evaluate the impact of increasing water and steam flows (ranging from 0% to 200% of the fuel mass flow) onto the emissions levels (NO and CO) of the engine. 相似文献
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We give an algorithm for constructing a basis and a multiplication table of a finite-dimensional finitely-presented Lie ring. Secondly, we give relations that are equivalent to the n-Engel condition, and only have to be checked for the elements of a basis of a Lie ring. We apply this to construct the freest t-generator Lie rings that satisfy the n-Engel condition, for (t,n)=(2,3),(3,3),(4,3),(2,4). 相似文献