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761.
Martina Sandholzer Alexandra Lex Gregor Trimmel Robert Saf Franz Stelzer Christian Slugovc 《Journal of polymer science. Part A, Polymer chemistry》2007,45(7):1336-1348
A convenient synthetic route towards polymerizable fluorescein, dicholorofluorescein, and eosin dyes is presented. Polymerizability was provided by linking 2‐norbornene carboxylic acid, 11‐bromo‐undecyl ester to the dye's carboxylate functionality. Although the monomers bearing dichlorofluorescein and eosin were obtained in high yield, the related fluorescein bearing monomer could only be obtained in low yield. In the latter case, concurring etherification and esterification led to a product mixture of the desired carboxy modified monomer and a double substituted by‐product. The dye‐monomers were used successfully for the preparation of statistical copolymers with endo,exo‐2,3‐norbornene dicarboxylic acid dimethylester by ROMP. Absorption and luminescence characteristics and, in particular, the acid/base sensitive behavior of the parent dyes were preserved in the monomers and copolymers. The absorption and emission maxima in THF solution and in the solid state were red shifted in comparison to the aqueous samples of the parent dyes. Dye‐copolymers exhibited good film forming properties. Solid state luminescence studies of the copolymers revealed an increasing sensitivity towards NEt3 vapor in the order fluorescein < dichlorofluorescein < eosin bearing copolymer. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1336–1348, 2007 相似文献
762.
763.
764.
P. Gregor 《Analytical and bioanalytical chemistry》1899,38(6):371-372
765.
766.
Gregor Dolinar Shuanping Du Jinchuan Hou Peter Legia 《Linear algebra and its applications》2008,429(1):100-109
Let be the space of all bounded linear operators on a Banach space X and let LatA be the lattice of invariant subspaces of the operator . We characterize some maps with one of the following preserving properties: Lat(Φ(A)+Φ(B))=Lat(A+B), or Lat(Φ(A)Φ(B))=Lat(AB), or Lat(Φ(A)Φ(B)+Φ(B)Φ(A))=Lat(AB+BA), or Lat(Φ(A)Φ(B)Φ(A))=Lat(ABA), or Lat([Φ(A),Φ(B)])=Lat([A,B]). 相似文献
767.
Georg Gregor 《Fresenius' Journal of Analytical Chemistry》1894,33(1):30-45
Ohne Zusammenfassung 相似文献
768.
769.
Total electron yields for perpendicular impact of C+ ions on W have been measured for projectile energies from 0.2 keV to 7 keV. The data are compared with the data of C+ bombardment of gold and graphite in order to demonstrate general trends in kinetic electron yields at low projectile velocities. The total electron yields in the studied combinations of projectiles and substrates show a similar exponential dependence Γ ∝ (v/A) exp(−A/v), where A is a constant and v is the projectile velocity. 相似文献
770.
Tarbert CM Watts DP Aguar P Ahrens J Annand JR Arends HJ Beck R Bekrenev V Boillat B Braghieri A Branford D Briscoe WJ Brudvik J Cherepnya S Codling R Downie EJ Föhl K Glazier DI Grabmayr P Gregor R Heid E Hornidge D Jahn O Kashevarov VL Knezevic A Kondratiev R Korolija M Kotulla M Krambrich D Krusche B Lang M Lisin V Livingston K Lugert S Macgregor IJ Manley DM Martinez M McGeorge JC Mekterovic D Metag V Nefkens BM Nikolaev A Novotny R Owens RO Pedroni P Polonski A Prakhov SN Price JW Rosner G 《Physical review letters》2008,100(13):132301
We present the first detailed measurement of incoherent photoproduction of neutral pions to a discrete state of a residual nucleus. The 12C(gamma,pi(0))(12)C*(4.4 MeV) reaction has been studied with the Glasgow photon tagger at MAMI employing a new technique which uses the large solid angle Crystal Ball detector both as a pi(0) spectrometer and to detect decay photons from the excited residual nucleus. The technique has potential applications to a broad range of future nuclear measurements with the Crystal Ball and similar detector systems elsewhere. Such data are sensitive to the propagation of the Delta in the nuclear medium and will give the first information on matter transition form factors from measurements with an electromagnetic probe. The incoherent cross sections are compared to two theoretical predictions including a Delta-hole model. 相似文献