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991.
992.
993.
Wojciech Pieczynski 《Comptes Rendus Mathematique》2003,336(10):869-872
The hidden Markov chains (HMC) (X,Y) have been recently generalized to triplet Markov chains (TMC), which enjoy the same capabilities of restoring a hidden process X from the observed process Y. The posterior distribution of X can be viewed, in an HMC, as a particular case of the so called “Dempster–Shafer fusion” (DS fusion) of the prior Markov with a probability q defined from the observation Y=y. As such, when we place ourselves in the Dempster–Shafer theory of evidence by replacing the probability distribution of X by a mass function M having an analogous Markov form (which gives again the classical Markov probability distribution in a particular case), the result of DS fusion of M with q generalizes the conventional posterior distribution of X. Although this result is not necessarily a Markov distribution, it has been recently shown that it is a TMC, which renders traditional restoration methods applicable. The aim of this Note is to present some generalizations of the latter result: (i) more general HMCs can be considered; (ii) q, which can possibly be a mass function Q, is itself a result of the DS fusion; and (iii) all these results are finally specified in the hidden Markov trees (HMT) context, which generalizes the HMC one. To cite this article: W. Pieczynski, C. R. Acad. Sci. Paris, Ser. I 336 (2003). 相似文献
994.
Wojciech Jabłoński 《Aequationes Mathematicae》2007,74(3):287-309
We determine all homomorphisms of the differential group L1sL^1_s with arbitrary s ≥ 2 into the group L1rL^1_r for r ≤ 3. 相似文献
995.
AgO is a prototypical mixed‐valence compound, with markedly different coordination environment of dumbbell Ag(1+) and low‐spin square‐planar Ag(3+) which render it a narrow band gap semiconductor. The hybrid HSE06 functional reproduces fairly well the band gap of its P 21/c form at ambient conditions (ΔEexp = 1.0–1.1 eV, ΔEtheor = 0.94 eV) and suggest progressive band gap decrease with external pressure with metallization at 50 GPa via band overlap. Dynamic (phonon) instability appears at the onset of metallization leading to a structural phase transition to a more stable but still metallic form. The density of electronic states at the Fermi level of the polymorph is small and a pseudo‐gap at the Fermi level is preserved.
996.
997.
Prof. Jiří Kulhánek Prof. Filip Bureš Dr. Wojciech Kuznik Prof. Iwan V. Kityk Dr. Tomáš Mikysek Prof. Aleš Růžička 《化学:亚洲杂志》2013,8(2):465-475
A series of new nonlinear optical chromophores ( 1 – 15 ) that were comprised of ferrocene‐donor and 4,5‐dicyanoimidazole‐acceptor moieties and various π linkers of different length were synthesized. Support for the presence of significant D ? A interactions in these NLO‐phores was obtained from the evaluation of the quinoid character of the 1,4‐phenylene moieties and their electronic absorption spectra, which featured intense high‐energy (HE) bands that were accompanied by less‐intense low‐energy (LE) bands. The redox behavior of these compounds was investigated by cyclic voltammetry (CV) and by rotating‐disc voltammetry (RDV); their electrochemical gaps decreased steadily from 2.64 to 2.09 V. In addition to the experimentally obtained data, DFT calculations of their absorption spectra, HOMO/LUMO levels, and second‐order polarizabilities (β) (?2ω,ω,ω) were performed. A structure–property relationship study that was performed by systematically altering the π linker revealed that the intramolecular charge‐transfer and nonlinear optical properties of these inorganic–organic hybrid D? π? A systems ( 1 – 15 ) were primarily affected by: 1) The presence of olefinic/acetylenic subunits; 2) the length of the π linker; and 3) the spatial arrangement (planarity) of the π linker. 相似文献
998.
Piotr A. Gauden Artur P. Terzyk Sylwester Furmaniak Marek Wiśniewski Piotr Kowalczyk Agnieszka Bielicka Wojciech Zieliński 《Adsorption》2013,19(2-4):785-793
Experimental data of nitrogen adsorption (T = 77.3 K) from gaseous phase measured on commercial closed carbon nanotubes are presented. Additionally, we show the results of N2 adsorption on compressed (using hydraulic press) CNTs. In order to explain the experimental observations the results of GCMC simulations of N2 adsorption on isolated or bundled multi-walled closed nanotubes (four models of bundles) are discussed. We show that the changes of the experimental adsorption isotherms are related to the compression of the investigated adsorbents. They are qualitatively similar to the theoretical observations. Taking into account all results it is concluded that in the “architecture” of nanotubes very important role has been played by isolated nanotubes. 相似文献
999.
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
1000.
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