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141.
Gritsan N. P. Bagryansky V. A. Vlasyuk I. V. Molin Yu. N. Makarov A. Yu. Platz M. S. Zibarev A. V. 《Russian Chemical Bulletin》2001,50(11):2064-2070
Photolysis of 12-electron, formally antiaromatic, 1,3,2,4-benzodithiadiazine (1a) and its tetrafluoro-substituted derivative (1b) was studied in glassy matrices at 77 K and in an argon matrix at 14 K by UV, IR, and ESR spectroscopy. In these matrices, a diamagnetic species (3a,b) is formed as a persistent species. It is product of the intramolecular transformations of heterocycles 1a,b and the precursor of 1,2,3-benzodithiazolyl radicals (2a,b). The nitrenoid structure, intermediate between the structures of singlet 1,2,3-benzodithiazol-2-ylnitrene RS—N: and the corresponding thiazyl RSN, was ascribed to intermediate 3a,b in agreement with the data of IR spectroscopy. 相似文献
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Dal Molin M Gasparini G Scrimin P Rastrelli F Prins LJ 《Chemical communications (Cambridge, England)》2011,47(46):12476-12478
(13)C-isotope labelling is presented as a novel tool for the study of complex chemical systems. (13)C-isotope labelling permits the quantification of all 26 members of a dynamic library from a single (13)C NMR spectrum without the need for advanced instrumentation or sophisticated experimental protocols. 相似文献
144.
Self‐made microextraction by packed sorbent device for the cleanup of polychlorinated biphenyls from bovine serum 下载免费PDF全文
Liu Yang Qiang Han Shuya Cao Junchao Yang Jiang Zhao Molin Qin Mingyu Ding 《Journal of separation science》2016,39(8):1518-1523
Microextraction by packed sorbent, a miniaturized form of the solid‐phase extraction, is a new sample pretreatment technology mainly used for bioanalysis. In this work, self‐made device was fabricated by packing C18 sorbent into a microinjection needle (50 μL) and then applied for the analysis of polychlorinated biphenyls in bovine serum followed by gas chromatography with mass spectrometry determination. Compared with conventional solid‐phase extraction, the developed method bears many intriguing properties such as low consumption of the sample and organic solvent, time‐saving and easy operation, which are of great interest and desire for bioanalysis applications. A series of parameters that affect the analytical performance, such as the type of elution, the aspirating/dispensing cycles of sample loading and elution, washing solution, and matrix effects, was investigated in detail. Under the optimized conditions, the proposed method presented a good linearity (R ≥ 0.986) and satisfactory sensitivity and limits of detection (0.06–0.53 ng/mL) and quantification (0.20–1.77 ng/mL), respectively. In addition, satisfactory recoveries (60.0–91.4%) and accuracy (RSD ≤ 5.72%) were achieved after optimizing the conditions when applying the developed method to real sample analysis. The screening of polychlorinated biphenyls residues in bovine serum samples by the developed method demonstrated that the assay is ideally suited as a monitoring method for polychlorinated biphenyls residues in bioanalysis. 相似文献
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A. I. Potapov D. V. Stass E. Yu. Fursova N. N. Lukzen G. V. Romanenko V. I. Ovcharenko Yu. N. Molin 《Applied magnetic resonance》2008,35(1):43-55
We suggest that intramolecular exchange coupling J in solutions can possibly be measured with just a ruler using an analogue of the nuclear magnetic resonance paramagnetic
shift. If one of the two coupled electron spins is rapidly relaxing, the resulting electron paramagnetic resonance (EPR) spectrum
of the system is the resolved spectrum for the second spin with a shifted g-factor. The amount and the sense of the shift are both linear in J, which thus can be obtained from the measured shift by simple algebra. We prepared a set of complexes of rare-earth ions
with nitroxides to probe this idea, but the sought effect was not yet found indicating J < 0.1 cm−1 for these systems. Either the radical centers should be brought closer to the central lanthanide ion, or the ion itself should
be substituted for a rapidly relaxing transition-metal ion, e.g., Cr2+ or Co2+. Furthermore we report evolving EPR spectra that reflect the inner life of the complexes in solution.
Authors' address: Dmitri Stass, Institute of Chemical Kinetics and Combustion, Russian Academy of Sciences, 630090 Novosibirsk,
Russia 相似文献