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71.
[structure: see text] An o-allenyl-p-methoxyphenol intermediate (Int) was for the first time proved to be involved in the photochromic reaction of 2,2-di(4-fluorophenyl)-6-methoxy-2H-1-chromene (FC). Transoid-cis (TC) and transoid-trans (TT) photomerocyanines and the intermediate Int are generated by UV irradiation of FC. Visible light converts TC and TT into Int. The monitoring of the reactions was carried out on the basis of (1)H, (13)C, (19)F, and (2)H NMR spectroscopy. 相似文献
72.
We investigate the low-noise regime of a large class of probabilistic cellular automata, including the North-East-Center model of Toom. They are defined as stochastic perturbations of cellular automata belonging to the category of monotonic binary tessellations and possessing a property of erosion. We prove, for a set of initial conditions, exponential convergence of the induced processes toward an extremal invariant measure with a highly predominant spin value. We also show that this invariant measure presents exponential decay of correlations in space and in time and is therefore strongly mixing. 相似文献
73.
Okadaic acid (OA), a lipophilic phycotoxin highly toxic to humans is produced by toxigenic dinoflagellates. The need to develop high performing methods for OA analysis able to improve the traditional ones is evident. In this work, competitive indirect enzyme-linked electrochemical immunosensor based on super paramagnetic nanobeads has been developed for the detection of OA. Streptavidin-coated magnetic beads were used as support to immobilize the biotinylated OA. Preliminary, colorimetric tests were performed in order to optimize different experimental parameters. Electrochemical detection was carried out by differential pulse voltammetry (DPV). The limit of detection (LOD) (0.38 μg L−1), the mid point value (IC50) (3.15 μg L−1) and the time needed (60 min) for analysis of a real sample validated the developed electrochemical immunosensor as a promising tool for routine use. The matrix effect and the recovery rate were also assessed, showing an excellent percentage of recovery. 相似文献
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Juan‐Ramn Jimnez Jana Glatz Amina Benchohra Geoffrey Gontard Lise‐Marie Chamoreau Jean‐Franois Meunier Azzedine Bousseksou Rodrigue Lescouëzec 《Angewandte Chemie (International ed. in English)》2020,59(21):8089-8093
A mixed‐valence {MnII3MnIIIFeII2FeIII2} cyanide‐bridged molecular cube hosting a caesium cation, Cs?{Mn4Fe4}, was synthesized and structurally characterized by X‐ray diffraction. Cyclic‐voltammetry measurements show that its electronic state can be switched between five different redox states, which results in a remarkable electrochromic effect. Magnetic measurements on fresh samples point to the occurrence of a spin‐state change near room temperature, which could be ascribed to a metal‐to‐metal electron transfer converting the {FeII?CN?MnIII} pair into a {FeIII?CN?MnII} pair. This feature was only previously observed in the polymeric MnFe Prussian‐blue analogues (PBAs). Moreover, this novel switchable molecule proved to be soluble and stable in organic solvents, paving the way for its integration into advanced materials. 相似文献
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C. Matignon G. Marchal W. Bothe O. Erbacher K. Philipp K. Donat O. Hahn J. Heidenhain J. St. van der Lingen F. Tödt O. von Baeyer Lise Jette W. West F. Paneth P. Beer F. Richter K. Horovitz A. Lottermoser F. Haber K. Fajans K. v. Beckerath L. Michaelis Sh. Dokan J. N. Mukherjee M. Centnerszwer M. Straumanis T. Isnardi und I. Langmuir 《Fresenius' Journal of Analytical Chemistry》1932,87(5-6):200-211
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