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991.
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Hong-Jian Feng 《Journal of magnetism and magnetic materials》2012,324(2):178-182
Ab initio calculations show that the coupling between antiferrodistortive (AFD) distortions and magnetization in perovskite Bi2FeMnO6 is prohibited to make magnetization rotate as effective Hubbard parameter is larger than 2.7 eV, where anomalies in antiferromagnetic (AFM) vectors and band gap varying with on-site Coulomb interaction can be observed. This coupling is attributed to the antisymmetric Dzyaloshinskii-Moriya interaction driven by the eg-eg states AFM interaction and charge redistribution with respect to different AFD distortions. 相似文献
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《Journal of computational chemistry》2018,39(8):438-449
Excitation energy transfer (EET) determines the fate of sunlight energy absorbed by light‐harvesting proteins in natural photosynthetic systems and photovoltaic cells. As previously reported (D. Kosenkov, J. Comput. Chem. 2016, 37(19), 1847), PyFREC software enables computation of electronic couplings between organic molecules with a molecular fragmentation approach. The present work reports implementation of direct fragmentation‐based computation of the electronic couplings and EET rates in pigment–protein complexes within the Förster theory in PyFREC. The new feature enables assessment of EET pathways in a wide range of photosynthetic complexes, as well as artificial molecular architectures that include light‐harvesting proteins or tagged fluorescent biomolecules. The developed methodology has been tested analyzing EET in the Fenna–Matthews–Olson (FMO) pigment–protein complex. The pathways of excitation energy transfer in FMO have been identified based on the kinetics studies. © 2017 Wiley Periodicals, Inc. 相似文献
994.
Ph. Pruzan J. C. Chervin M. M. Thiéry J. P. Itié J. M. Besson J. P. Forgerit 《高压研究》2013,33(1-6):215-217
Abstract After a pressure cycle to 30 GPa, benzene transforms to a white solid which can be recovered at ambient. Results obtained from infrared spectroscopy and other physico-chemical methods show that the recovered solid is a highly cross-linked polymer. The molecular structure of benzene is very likely completely altered by the transformation. 相似文献
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Abstract An anthrylpolyamine chemosensor, whose fluorescence is partially quenced upon electrostatic complexation to ATP, can be used to monitor the action of an enzyme (apyrase) that hydrolyses ATP to AMP and inorganic phosphate. 相似文献
996.
《Composite Interfaces》2013,20(8-9):787-803
Poly(amide)-6/clay nanocomposites are investigated by means of modulated temperature differential scanning calorimetry. The importance of polymer–filler interaction is explored by comparing nanocomposites based on untreated and organically modified clay. During quasi-isothermal crystallization experiments, an excess contribution is observed in the recorded heat capacity signal due to reversible melting and crystallization. The magnitude of this excess contribution depends on the nanocomposite investigated. We suggest that it is directly related to the segmental mobility of the polymer chains in the interphase region. As such, the magnitude of this excess contribution can be used to quantify the efficiency of the polymer–clay interaction. Depending on the clay type used, differences in interfacial interaction can be achieved, which is of great importance with respect to the improvement of material properties. Based on thermal analysis results, a simple interphase model is proposed that is able to account for both the thermal and mechanical properties of poly(amide)-6/clay nanocomposites. 相似文献
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