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31.
Perylene bisimide (PBI) is a fluorescent dye which has strong emission and high photostability. Although PBI has been widely used for industrial materials, the application of PBI in analytical fields was limited mainly due to its high hydrophobicity. In recent years, however, unique and useful analytical methods based on PBI platform are being successfully developed by utilizing the characteristic features of this compound including its high hydrophobicity. In this article, the recent trend of environmental and biological analysis using PBI is reviewed. 相似文献
32.
A rhodium-catalyzed asymmetric addition of readily available potassium organotrifluoroborates to both N-tosyl and N-nosyl ketimines has been developed. High enantioselectivity has been achieved by using a chiral diene ligand, and the nosyl group of the addition products can be easily removed while retaining the enantiomeric purity. 相似文献
33.
Péter Csomós Lajos Fodor Antal Csámpai Pál Sohár 《Journal of heterocyclic chemistry》2011,48(5):1079-1084
We report a convenient approach for the synthesis of a new ring system: 4,5‐dihydro‐1,3‐thiazino[5,4‐b]indoles. The procedure involves the use of Lawesson's reagent in the presence of silica to achieve the one‐step ring‐closure reactions of 2‐benzoylamino‐3‐hydroxymethylindole intermediates to furnish 4,5‐dihydro‐2‐aryl‐1,3‐thiazino[5,4‐b]indoles. 2‐Phenylimino‐1,3‐thiazino[5,4‐b]indoles were obtained via the corresponding 3‐phenylthiourea‐2‐carboxylic acid ester derivatives by chemoselective reduction of the ester group, followed by ring closure under acidic conditions. The structures of the novel products were elucidated by IR, 1H‐NMR, and 13C‐NMR spectroscopy, including 2D‐HMQC, 2D‐HMBC, and DEPT measurements. J. Heterocyclic Chem., (2011). 相似文献
34.
Maiti KK Samanta A Vendrell M Soh KS Olivo M Chang YT 《Chemical communications (Cambridge, England)》2011,47(12):3514-3516
SERS nanotags have been prepared to accomplish the multiplex detection of cancer cells. Herein we evaluated the adequacy of lipoic acid-containing cyanine derivatives (Cy3LA and Cy5LA) to function as multiplex partners with a triphenylmethine Raman reporter (B2LA) under a single excitation wavelength. SERS experiments enabled the multiplex recognition of two different cancer cells with antibody-conjugated nanotags that were derivatized with optimized cyanine and triphenylmethine reporters. 相似文献
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37.
Banbara Mutsunori Inoue Katsumi Kaufmann Benjamin Okimoto Tenda Schaub Torsten Soh Takehide Tamura Naoyuki Wanko Philipp 《Annals of Operations Research》2019,275(1):3-37
Annals of Operations Research - Answer Set Programming (ASP) is an approach to declarative problem solving, combining a rich yet simple modeling language with high performance solving capacities.... 相似文献
38.
Chin‐Ann Soh 《Journal of Graph Theory》2007,55(1):14-26
The circular chromatic number is a refinement of the chromatic number of a graph. It has been established in [3,6,7] that there exists planar graphs with circular chromatic number r if and only if r is a rational in the set {1} ∪ [2,4]. Recently, Mohar, in [1,2] has extended the concept of the circular chromatic number to digraphs and it is interesting to ask what the corresponding result is for digraphs. In this article, we shall prove the new result that there exist planar digraphs with circular chromatic number r if and only if r is a rational in the interval [1,4]. © 2006 Wiley Periodicals, Inc. J Graph Theory 55: 14–26, 2007 相似文献
39.
Year-long biophoton measurements: normalized frequency count analysis and seasonal dependency 总被引:2,自引:0,他引:2
Jung HH Yang JM Woo WM Choi C Yang JS Soh KS 《Journal of photochemistry and photobiology. B, Biology》2005,78(2):149-154
Biophoton emissions from three healthy human subjects were measured for 52 weeks. The active nature of dorsal hands and personal discernable patterns in palmar hands were investigated through frequency count analysis of biophoton emission rates. Also, the seasonal dependency of biophoton emission rates from human hands was studied and we found that emission rates were lowest in autumn. There was a reversion of relative emission rates from the palms and the dorsa depending upon the season. The emission rates from the palms remain rather stable throughout the year, but those from the dorsa vary widely depending upon the season. These features of biophoton emission rates were considered in light of the diagnostic view of traditional Chinese medicine. 相似文献
40.
Găină L Csámpai A Túrós G Lovász T Zsoldos-Mády V Silberg IA Sohár P 《Organic & biomolecular chemistry》2006,4(23):4375-4386
A series of novel 3(5)-aryl/ferrocenyl-5(3)-phenothiazinylpyrazoles and pyrazolines were obtained by substituent-dependent regioselective condensation of the corresponding (E)-3-(2-alkyl-10H-phenothiazin-3-yl)-1-aryl/ferrocenylprop-2-en-1-one with hydrazine or methylhydrazine in acetic acid. The different propensity of the primary formed beta-hydrazino adducts to undergo competitive retro-Mannich reaction was interpreted in terms of tautomerisation equilibrium constants calculated by DFT using a solvent model. The regioselectivity of the cyclisation reactions with methylhydrazine and the substituent-dependent redox properties of pyrazolines were also rationalized by comparative DFT calculations performed for simplified model molecules. On the effect of ultrasound-promoted oxidation with copper(II)nitrate phenothiazine-containing pyrazolines, enones and oxo-compounds were selectively transformed into sulfoxides. Only one sulfoxide enone was partially converted into an oxirane derivative. The structure of the novel products was determined by IR and NMR spectroscopy including COSY, HSQC, HMBC and DNOE measurements. 相似文献