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971.
Jianguo Sun Qiaomei Sun Anna Plewa Yumei Wang Linchun He Feng Zheng Chao Chen Wojciech Zajac Janina Molenda Kaiyang Zeng Li Lu 《Angewandte Chemie (International ed. in English)》2020,59(23):8991-8997
In hunting for safe and cost‐effective materials for post‐Li‐ion energy storage, the design and synthesis of high‐performance solid electrolytes (SEs) for all‐solid‐state batteries are bottlenecks. Many issues associated with chemical stability during processing and storage and use of the SEs in ambient conditions need to be addressed. Now, the effect of water as well as oxyhdryl group (.OH) on NaBi3O4Cl2 are investigated by evaluating ionic conductivity. The presence of water and .OH results in an increase in ionic conductivity of NaBi3O4Cl2 owing to diffusion of H2O into NaBi3O4Cl2, partially forming binding .OH through oxygen vacancy repairing. Ab initio calculations reveal that the electrons significantly accumulate around .OH and induce a more negative charge center, which can promote Na+ hopping. This finding is fundamental for understanding the essential role of H2O in halide‐based SEs and provides possible roles in designing water‐insensitive SEs through control of defects. 相似文献
972.
Andy S. Sardjan Dr. Palas Roy Dr. Wojciech Danowski Giovanni Bressan Dr. Laura Nunes dos Santos Comprido Prof. Wesley R. Browne Prof. Ben. L. Feringa Prof. Stephen R. Meech 《Chemphyschem》2020,21(7):594-599
Efficient photomolecular motors will be critical elements in the design and development of molecular machines. Optimisation of the quantum yield for photoisomerisation requires a detailed understanding of molecular dynamics in the excited electronic state. Here we probe the primary photophysical processes in the archetypal first generation photomolecular motor, with sub-50 fs time resolved fluorescence spectroscopy. A bimodal relaxation is observed with a 100 fs relaxation of the Franck-Condon state to populate a red-shifted state with a reduced transition moment, which then undergoes multi-exponential decay on a picosecond timescale. Oscillations due to the excitation of vibrational coherences in the S1 state are seen to survive the ultrafast structural relaxation. The picosecond relaxation reveals a strong solvent friction effect which is thus ascribed to torsion about the C−C axle. This behaviour is contrasted with second generation photomolecular motors; the principal differences are explained by the existence of a barrier on the excited state surface in the case of the first-generation motors which is absent in the second generation. These results will help to provide a basis for designing more efficient molecular motors in the future. 相似文献
973.
974.
975.
Honorata Mąka Wojciech Sikorski 《International Journal of Polymer Analysis and Characterization》2014,19(8):682-692
Epoxy compositions based on low-molecular bisphenol A type resin and deep eutectic solvents from choline chloride (ChCl) and guanidine derivatives or urea were prepared and investigated. Pot life at room temperature and curing process at dynamic mode were studied using DSC and rheometry while DES basic ratio was changed in a range of 3–9 wt. part/100 wt. part of epoxy resin (phr). Thermomechanical properties (glass transition and tan δ) of the cured epoxy materials (DES content up to 20 phr) using DMTA and their thermal resistance on the basis of thermogravimetric measurements were evaluated. The curing mechanism, i.e., ratio of polyaddition reaction to catalytic polymerization, was evaluated considering changeable guanidine derivative content in relation to epoxy resin. 相似文献
976.
Maciej Sowa Alicja Kazek-Kęsik Agnieszka Krząkała Robert P. Socha Grzegorz Dercz Joanna Michalska Wojciech Simka 《Journal of Solid State Electrochemistry》2014,18(11):3129-3142
Herein, a study of the plasma electrolytic oxidation (PEO) of niobium in an anodising bath composed of potassium silicate (K2SiO3) and potassium hydroxide (KOH) is reported. The effects of the K2SiO3 concentration in the bath and the process voltage on the characteristics of the obtained oxide layers were assessed. Compact, barrier-type oxide layers were obtained when the process voltage did not exceed the breakdown potential of the oxide layer. When this threshold was breached, the morphology of the oxide layer changed markedly, which is typical of PEO. A significant amount of silicon, in the form of amorphous silica, was incorporated into the oxide coatings under these conditions compared with the amount obtained with conventional anodising. This surface modification technique led to an improvement in the corrosion resistance of niobium in Ringer’s solution, regardless of the imposed process conditions. 相似文献
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978.
JPC – Journal of Planar Chromatography – Modern TLC - 相似文献
979.
The existence of a periodic solution to an impulsive differential inclusion being invariant with respect to a non-convex set of state constraints is established by the use a Lefschetz type fixed-point theorem for set-valued maps. 相似文献
980.
Irena Pawow Wojciech M. Zajaczkowski 《Mathematical Methods in the Applied Sciences》2006,29(7):853-876
In this paper, we prove the classical solvability of a nonlinear 1‐D system of hyperbolic–parabolic type arising as a model of phase separation in deformable binary alloys. The system is governed by the nonstationary elasticity equation coupled with the Cahn–Hilliard equation. The existence proof is based on the application of the Leray–Schauder fixed point theorem and standard energy methods. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献