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Applied Mathematics and Mechanics - The type B aortic dissection (TBAD) is a perilous disease with high morbidity and mortality rates. The hemodynamics of TBAD in different scenarios has been... 相似文献
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Interfacial interactions of Nafion ionomer with superhydrophilic (Pt, Au), hydrophilic (SiO2), and hydrophobic (graphene, octyltrichlorosilane [OTS]‐modified SiO2) is investigated, using in situ thermal ellipsometry, by quantification of substrate‐ and thickness‐dependent thermal properties of the ultrathin Nafion films of nominal thickness ranging 25–135 nm. For sub‐50 nm thin Nafion films, the thermal expansion coefficient of films decreased in the order of most hydrophobic to most hydrophilic substrate: OTS > graphene > SiO2 > Au > Pt, implying weaker interpolymer and polymer–substrate interactions for films on hydrophobic substrates. Expansion coefficient of films on SiO2, graphene, and OTS‐modified SiO2 decreased with thickness whereas that of films on Au and Pt substrates increased with thickness. Above ~100 nm of thickness, films on all substrates converged toward a common value representative of bulk Nafion. Thermal transition temperature was found to be higher for films on hydrophilic SiO2 than that for films on hydrophobic graphene and OTS‐modified SiO2 but was not discernible for films on Au and Pt substrates. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57, 343–352 相似文献
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Dr. Ze-Lin Zhu Sheng-Fu Wang Li-Wen Fu Ji-Hua Tan Chen Cao Dr. Yi Yuan Shek-Man Yiu Dr. Ye-Xin Zhang Prof. Yun Chi Prof. Chun-Sing Lee 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(4):e202103202
Upon fusing the pyrazinyl pyrazole entity in giving pyrazolo[3,4-f]quinoxaline chelate, the corresponding Os(II) based NIR emitter exhibited “invisible” and efficient electroluminescence with a peak maximum at 811 nm. A maximum external quantum efficiency of 0.97 % and a suppressed efficiency roll-off till a current density of 300 mA cm−2 was also exhibited. 相似文献
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Alba Vargas‐Caamal Jose Luis Cabellos Filiberto Ortiz‐Chi Henry S. Rzepa Albeiro Restrepo Gabriel Merino 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(8):2812-2818
The potential energy surfaces of the HCl(H2O)n (n is the number of water molecules) clusters are systematically explored using density functional theory and high‐level ab initio computations. On the basis of electronic energies, the number of water molecules needed for HCl dissociation is four as reported by some experimental groups. However, this number is five owing to the inclusion of entropic factors. Wiberg bond indices are calculated and analyzed, and the results provide a quadratic correlation and classification of clusters according to the nondissociated, partially dissociated, and fully dissociated character of the H?Cl bond. Our computations show that if temperature is not controlled during the experiment, the values obtained for the dipole moment (or for any measurable property) are susceptible to change, providing a different picture of the number of water molecules needed for HCl dissociation in a nanoscopic droplet. 相似文献
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Jie Yang Zichun Ren Zongliang Xie Yingjie Liu Can Wang Yujun Xie Prof. Qian Peng Prof. Bin Xu Prof. Wenjing Tian Prof. Fan Zhang Prof. Zhenguo Chi Prof. Qianqian Li Prof. Zhen Li 《Angewandte Chemie (International ed. in English)》2017,56(3):880-884
We report the first example of an AIEgen (DPP-BO) with fluorescence–phosphorescence dual emission under mechanical stimulation. By carefully analyzing the crystal structure of DPP-BO, the efficient intermolecular and intramolecular interactions should account for its unique mechanoluminescence (ML) properties, especially the abnormal phosphorescence, as further confirmed by controlled experiments and theoretical calculations for the presence of ISC transitions. These results provide important information for understanding the complex ML process, possibly opening up a new way to study the inherent mechanism of ML by broadening the application of AIEgens. 相似文献