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991.
In this paper,we are concerned with the existence and non-existence of global solutions of a semi-linear heat equation with fractional Laplacian.We obtain some extension of results of Weissler who considered the case α = 1,and h ≡ 1. 相似文献
992.
First-principles study of structural stability and elastic property of pre-perovskite PbTiO3
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The structural stability and the elastic properties of a novel structure of lead titanate,which is named preperovskite PbTiO3 (PP-PTO) and is constructed with TiO6 octahedral columns arranged in a one-dimensional manner,are investigated by using first-principles calculations.PP-PTO is energetically unstable compared with conventional perovskite phases,however it is mechanically stable.The equilibrium transition pressures for changing from preperovskite to cubic and tetragonal phases are 0.5 GPa and 1.4 GPa,respectively,with first-order characteristics.Further,the differences in elastic properties between pre-perovskite and conventional perovskite phases are discussed for the covalent bonding network,which shows a highly anisotropic character in PP-PTO.This study provides a crucial insight into the structural stabilities of PP-PTO and conventional perovskite. 相似文献
993.
Synthesis and characterization of eumelanin‐inspired poly(indoylenearylenevinylene)s and poly(indoylenearyleneethynylene)s
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Santosh Adhikari RaiAnna A. Hopson Bhishma R. Sedai Frederick M. McFarland Song Guo Toby L. Nelson 《Journal of polymer science. Part A, Polymer chemistry》2017,55(3):457-463
Four novel conjugated polymers containing the eumelanin‐inspired indole core have been successfully synthesized using common cross coupling reactions. These polymers differed by the arylene and the carbon–carbon bond linkage. Optoelectronic experiments of these polymers suggest that the ethynylene linkage contributed to the red‐shifted absorption spectra and blue‐shifted emission spectra when compared to the vinylene linkage polymers. Furthermore, the optical bandgaps of the poly(indoylenearyleneethynylene)s (PIAEs) were smaller compared to the poly(indoylenearylenevinylene)s (PIAVs). Surprisingly, the HOMOs of these polymers were less affected by the nature of the carbon–carbon linkage. However, the LUMOs of the PIAEs were lower in comparison to the PIAVs. These eumelanin‐inspired PIAEs and PIAVs are good fluorophores with fluorescence quantum yields ranging from 0.12 to 0.67 and have good thermal stability for applications such as in organic light‐emitting diodes. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 457–463 相似文献
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Wang Zhongtang Wen Wei Quan Wei Du Liang Wang Ping Lin Jinxian Xie Yun Tan Zhaoyi 《Journal of Radioanalytical and Nuclear Chemistry》2018,316(1):411-417
Journal of Radioanalytical and Nuclear Chemistry - Plutonium is one of the key radionuclides in nuclear decommission. In this study, a rapid method was developed to analyze Pu for concrete samples... 相似文献
998.
Gao Jian Ma Na Tian Jianjun Shen Cong Wang Lili Yu Pengfei Chu Yuanyuan Liu Wei Tan Xiaoyao Li Xifei Yin Zhen 《Journal of Solid State Electrochemistry》2018,22(2):519-525
Journal of Solid State Electrochemistry - One-pot strategy to fabricate N, P co-doping carbon was developed based on the functional ionic liquid (IL) as the N, P, and C precursors. The IL featuring... 相似文献
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Journal of Radioanalytical and Nuclear Chemistry - As a result of nuclear power plant accidents such as Chernobyl and Fukushima, and even their maintenance, the soil is contaminated due to the... 相似文献
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