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671.
Dr. Karolina Hurej Weronika Oszczęda Ewelina Opas Dr. Szymon J. Zelewski Prof. Miłosz Pawlicki Dr. Michał J. Białek Dr. Łukasz Orzeł Prof. Lechosław Latos-Grażyński 《Angewandte Chemie (International ed. in English)》2023,62(28):e202303394
The insertion of palladium(II) into di-p-pyrirubyrin results in mutually convertible bimetallic complexes. Post-synthetic functionalization of one of them yielded bispalladium(II) dioxo-di-p-pyrirubyrin and, after demetallation, dioxo-di-p-pyrirubyrin, introducing for the first time the α,β′-pyridin-2-one unit into the macrocyclic frame. Bispalladium(II) di-p-pyrirubyrin 6 , bispalladium(II) dioxo-di-p-pyrirubyrin 9 , and dioxo-di-p-pyrirubyrin 10 absorb and emit light around 1000 nm and are characterized by high photostability. Thus, they are promising candidates for near-infrared photoacoustic dyes, ideally targeting ( 9 ) the wavelength of Yb-based fiber lasers. The incorporation of an α,β′-pyridine moiety into expanded porphyrins opens a highly interesting area of research due to the attractive optical and coordination properties of the resulting molecules. 相似文献
672.
Martin K. Leonowicz Marta Lawecka A. Ślawska-Waniewska Gulzhian I. Dzhardimalieva Aleksander S. Rozenberg Anatolii D. Pomogailo 《Macromolecular Symposia》2003,204(1):257-266
Metallopolymer nanocomposites on the bases of cobalt and iron acrylates as well as their cocrystallites have been obtained and characterized. Microstructure of the materials consists of both agglomerated and individual nanocrystallites which are homogeneously distributed in the polymer matrix. Mean crystallite size is 7-14 nm. All the composite materials exhibit soft magnetic properties at room temperature. The magnetic parameters are controlled by the intrinsic magnetic properties of the constituents and agglomeration of the particles. 相似文献
673.
Szymon Wójcik Valentin Mirceski Bogusław Baś Małgorzata Jakubowska 《Electroanalysis》2023,35(8):e202300040
This work demonstrates that quadruple-disk electrodes with an innovative design, iridium-platinum, platinum-glassy carbon, and iridium-glassy carbon can effectively function as a single sensor and act as a voltammetric electronic tongue in food profiling. The key strategy used was a novel technique called double-sampled differential square-wave voltammetry (DSSWV), which increased the resolution and enabled extraction of the full, hidden information available in the measuring signals. Four clustering validity indices, namely the Calinski – Harabasz index, Davies – Bouldin index, Silhouette index and gap statistics were employed to select the optimal sensor and methodology for interpreting the current samples. The best expected results were obtained using an iridium-platinum electrode combined with overall cathodic potential modulation using the DSSWV technique. Principal component analysis and polar dendrogram confirmed the correct clustering of different isotonic beverages. However, it was also demonstrated that in some variants of measurement and signal interpretation, it was not possible to group the samples appropriately. 相似文献
674.
Spectrally resolved thermoluminescence (TL) measurements provide a lot of information concerning trapping and recombination states in various dielectric materials. As long-lived luminescence is typically weak, this technique requires a very sensitive apparatus. This paper describes the measurement system that is used for studying spectrally resolved TL and phosphorescence decay in polymers. Exemplary investigations are presented for poly(N-vinylcarbazole) (PVK) thin films. The obtained spectra clearly indicate the influence of solvents (dioxane, chlorobenzene) and excitation wavelengths on TL in PVK samples. 相似文献
675.
Jan Łukaszczyk Piotr Benecki Katarzyna Jaszcz Monika Śmiga 《Macromolecular Symposia》2004,210(1):457-464
Polysuccinates with pendant allyl groups (PSAGE) were synthesized by melt copolymerization of succinic anhydride with allyl glycidyl ether and eventually other glycidyl ethers. It was found that PSAGE could be crosslinked by radical copolymerization with methyl methacrylate. Oxidized PSAGE considered as multifunctional epoxy resin was cured with use of glutaric anhydride to form solid material susceptible to hydrolytic degradation to water-soluble non-toxic products. Comb-like amphiphilic polysuccinates containing both pendant poly(oxyethylene) chains and epoxy groups have been synthesized as well and checked for their solubility in water. Properties of PSAGE-type polymers suggests their potential use as biomaterials and polymeric drug carries. Please note, in the print publication of D. Theis, T. Schmidt, K.-F. Arndt, Macromol. Symp. 210 (2004), 465, erroneously the DOI 10.1002/masy.200450651 is repeated. There, the DOI should read: 10.1002/masy.200450652 相似文献
676.
To characterize an activity of silica toward elastomers usually the parameters of the filler structure and a possibility of its interactions with macromolecules of a matrix are taken into consideration [1,2,3]. As a rule, low molecular weight substances of different polarity are dissolved in a rubber mix (e.g. accelerators, activators, crosslinking substances, etc). They undergo adsorption on the surface of active fillers what exerts an effect on a structure of a network formed and influences mechanical properties of vulcanizates at the same time. 相似文献