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Bozena PIATEK 《数学学报(英文版)》2011,27(4):635-646
In this paper we show that an iterative sequence generated by the Halpern algorithm converges to a fixed point in the case
of complete CAT(κ) spaces. Similar results for Hadamard manifolds were obtained in [Li, C., López, G., Martín-Márquez, V.: Iterative algorithms
for nonexpansive mappings on Hadamard manifolds. Taiwanese J. Math., 14, 541–559 (2010)], but we study a much more general case. Moreover, we discuss the Halpern iteration procedure for set-valued
mappings. 相似文献
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Dr. Łukasz Orzeł Dr. Dorota Rutkowska-Zbik Prof. Rudi van Eldik Prof. Leszek Fiedor Prof. Grażyna Stochel 《Chemphyschem》2021,22(4):344-348
The extensive speciation of copper(II) chloride in organic solvents varies with concentration, temperature, pressure and oxygen content, providing the ability to switch between different chlorophyll transmetalation pathways. We found that one of them is exceptionally suitable for the formation and stabilisation of the chlorophyll π-cation radical. This is due to unique redox cycling, which is coupled to the generation and transformation of various reactive oxygen species. In the presence of a proton donor, our system shows behavior which resembles that of superoxide dismutase (SOD). Regardless of light, chlorophyll acts as an electron transfer mediator. 相似文献
996.
Błażej Gierczyk Michał Cegłowski Marcin Kaźmierczak Maciej Zalas 《Magnetic resonance in chemistry : MRC》2012,50(9):637-641
The 1H, 13C and 15N spectra of aryl‐substituted 1,3,4‐thiadiazoles were recorded. The results obtained were correlated with Hammett coefficients. The experimental results were compared with DFT‐calculated chemical shifts. The results obtained were compared with those for 1,3,4‐oxadiazoles and 1,3,4‐selenadiazoles. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Kang Hee Ku Hyunseung Yang Se Gyu Jang Joona Bang Bumjoon J. Kim 《Journal of polymer science. Part A, Polymer chemistry》2016,54(2):228-237
Combining the functionality of nanoparticles (NPs) with the processability of polymers offers great promise for designing novel materials. In particular, NPs with tailored surface properties can effectively modify the interface between two distinct fluids and/or different polymer matrices which allows them to function as efficient surfactants. The efficiency of NP surfactants is strongly affected by their size and shape, which influences their adsorption energy to the interface, and the entropic contribution to the system. In this review, the assembly of size- and shape-controlled inorganic NPs at the interface of block copolymers (BCPs) and polymer blends has been focused. First, we discuss the design of size- and shape-controlled NP surfactants and we review the examples of NP surfactant-driven BCPs and polymer blend morphologies. In addition, we review the recent investigations of the morphological transition of BCP emulsion particles induced by NP surfactants. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 228–237 相似文献
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Synthesis of higher carbon sugars from dihydroxyacetone and d-arabinose: an organocatalytic approach
Maciej Cieplak Magdalena Ceborska Piotr Cmoch Sławomir Jarosz 《Tetrahedron: Asymmetry》2012,23(15-16):1213-1217
The reaction of 2,3:4,5-diacetone-d-arabinose with protected dihydroxyacetone catalyzed by l-proline afforded two diastereoisomeric octoses in a 7:1 ratio in 75% yield. The anti (3S,4S) configuration at the newly created stereogenic centers was assigned to the main isomer on the basis of the X-ray analysis. The same reaction when catalyzed with unnatural d-proline provided the same products in a 1:20 ratio. 相似文献