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81.
Elisabeth Holder Veronica Marin Alexander Alexeev Ulrich S. Schubert 《Journal of polymer science. Part A, Polymer chemistry》2005,43(13):2765-2776
A set of novel greenish‐yellow‐, yellow‐, and orange‐light‐emitting polymeric iridium(III) complexes were synthesized with the bridge‐splitting method. The respective dimeric precursor complexes, [Ir(ppy)2‐μ‐Cl]2 (ppy = 2‐phenylpyridine) and [Ir(ppy? CHO)2‐μ‐Cl]2 [ppy? CHO = 4‐(2‐pyridyl)benzaldehyde], were coordinated to 2,2′‐bipyridine carrying poly(ε‐caprolactone) tails. The resulting emissive polymers were characterized with one‐dimensional (1H) and two‐dimensional (1H? 1H correlation spectroscopy) nuclear magnetic resonance and infrared spectroscopy, gel permeation chromatography, and matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry, and the successful coordination of the iridium(III) centers to the 2,2′‐bipyridine macroligand was revealed. The thermal behavior was studied with differential scanning calorimetry and correlated with atomic force microscopy. Furthermore, the quantitative coordination was verified by both the photophysical and electrochemical properties of the mononuclear iridium(III) compounds. The photoluminescence spectra showed strong emissions at 535 and 570 nm. The color shifts depended on the substituents of the cyclometallating ligands. Cyclic voltammetry gave oxidation potentials of 1.23 V and 1.46 V. Upon the excitation of the films at 365 nm, yellow light was observed, and this could allow potential applications in light‐emitting devices. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2765–2776, 2005 相似文献
82.
Marin Katalinić 《Colloid and polymer science》1934,68(3):372-373
Ohne Zusammenfassung
L. D. Mahajan, Kolloid-Z.65, 20 (1933). 相似文献
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85.
Platov Yu. T. Metlenkin D. A. Platova R. A. Rassulov V. A. Vereshchagin A. I. Marin V. A. 《Journal of Applied Spectroscopy》2021,88(4):723-730
Journal of Applied Spectroscopy - The application of UV-VIS-NIR spectroscopy combined with multivariate analysis for the classification and identification of buckwheat groats was analyzed. Samples... 相似文献
86.
A metal-free synthesis of symmetrical anhydrides has been developed starting from aldehydes, both aliphatic and aromatic or primary benzylic alcohols. The reaction occurs at room temperature and makes use of trichloroisocyanuric acid (TCCA) as an oxidant providing the desired carboxylic anhydrides in satisfactory yields. 相似文献
87.
Lidia S. Konstantinova Natalia V. Obruchnikova Yulia V. Nelyubina Oleg A. Rakitin 《Tetrahedron》2010,66(24):4330-634
The treatment of 5H-1,2,3-dithiazole-5-thiones 1 in chloroform under reflux and 5H-1,2,3-dithiazol-5-ones 2 in THF at room temperature with primary aliphatic amines and benzylamine afforded 1,2,5-thiadiazole-3(2H)-thiones 3 and 1,2,5-thiadiazol-3(2H)-ones 6, respectively. The structure of dithiazolone 3f was confirmed by X-ray diffraction analysis. The reaction of dithiazolone 2e bearing an electron-donating methyl group in the 4-position gave 2-oxoacetamide 7e in high yield. The reaction of thiones 1 with secondary aliphatic amines in DMSO yielded 2-iminothioacetamides 8 in moderate yields together with elemental sulfur. Interestingly, the treatment of dithiazolones 2 with secondary amines under the same conditions afforded 2-oxoacetamides 9—the products of the hydrolysis of corresponding imino derivatives 10, which was isolated as 10b. A general mechanism was proposed for the formation of the products. 相似文献
88.
Antibacterial effects of the essential oils of commonly consumed medicinal herbs using an in vitro model 总被引:1,自引:0,他引:1
Soković M Glamočlija J Marin PD Brkić D van Griensven LJ 《Molecules (Basel, Switzerland)》2010,15(11):7532-7546
The chemical composition and antibacterial activity of essential oils from 10 commonly consumed herbs: Citrus aurantium, C. limon, Lavandula angustifolia, Matricaria chamomilla, Mentha piperita, M. spicata, Ocimum basilicum, Origanum vulgare, Thymus vulgaris and Salvia officinalis have been determined. The antibacterial activity of these oils and their main components; i.e. camphor, carvacrol, 1,8-cineole, linalool, linalyl acetate, limonene, menthol, a-pinene, b-pinene, and thymol were assayed against the human pathogenic bacteria Bacillus subtilis, Enterobacter cloacae, Escherichia coli O157:H7, Micrococcus flavus, Proteus mirabilis, Pseudomonas aeruginosa, Salmonella enteritidis, S. epidermidis, S. typhimurium, and Staphylococcus aureus. The highest and broadest activity was shown by O. vulgare oil. Carvacrol had the highest antibacterial activity among the tested components. 相似文献
89.
Lidia M. Ravelo-Pérez Antonio V. Herrera-HerreraJavier Hernández-Borges Miguel Ángel Rodríguez-Delgado 《Journal of chromatography. A》2010,1217(16):2618-2641
Since the first report in 1991, carbon nanotubes (CNTs) have shown great possibilities for a wide variety of processes and applications, which include their use as electrodes, sensors (gas, enzymatic, etc.), nanoprobes, electronic materials, field emitters, etc. The combination of structures, dimensions and topologies has provided physical and chemical attractive properties that are unparalleled by most known materials. Their applications have also reached the Analytical Chemistry field in which CNTs are being used as matrices in matrix assisted laser desorption ionization, stationary phases in either gas chromatography, high performance liquid chromatography or capillary electrochromatography, also as pseudostationary phases in capillary electrophoresis, etc. as well as new solid-phase extraction (SPE) materials. Concerning this last application the number of works has considerably increased in the last five years. This review article pretends to focus on the most important features and different applications of SPE using CNTs (including matrix solid-phase dispersion and solid-phase microextraction) covering articles published since their introduction up to now (September 2009). 相似文献
90.