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41.
Hawryluk RJ Adler H Alling P Ancher C Anderson H Anderson JL Ashcroft D Barnes CW Barnes G Batha S Bell MG Bell R Bitter M Blanchard W Bretz NL Budny R Bush CE Camp R Caorlin M Cauffman S Chang Z Cheng CZ Collins J Coward G Darrow DS DeLooper J Duong H Dudek L Durst R Efthimion PC Ernst D Fisher R Fonck RJ Fredrickson E Fromm N Fu GY Furth HP Gentile C Gorelenkov N Grek B Grisham LR Hammett G Hanson GR Heidbrink W Herrmann HW Hill KW Hosea J Hsuan H Janos A Jassby DL Jobes FC Johnson DW 《Physical review letters》1994,72(22):3530-3533
42.
István Bitter Gábor Tóth Áron Szöllősy István Hermecz Zoltán Mészáros 《Tetrahedron letters》1985,26(30):3621-3622
9-Bromo-6,7,8,9-tetrahydro-4-pyrido [1,2-]pyrimidin-4-ones react with sodium azide to afford 9-amino-6,7-dihydroanalogues. A mechanism involving a tricyclic tetrazine intermediate formed by neighbouring-group participation is suggested. 相似文献
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Wong-Foy A Saxena S Moulé AJ Bitter HM Seeley JA McDermott R Clarke J Pines A 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2002,157(2):235-241
Laser-polarized (129)Xe and a high-T(c)superconducting quantum interference device (SQUID) are used to obtain magnetic resonance images in porous materials at a magnetic field of 2.3 mT, corresponding to a Larmor frequency of 27 kHz. Image resolution of 1 mm is obtained with gradients of only 1 mT/m. The resolution of xenon chemical shifts in different physicochemical environments at ultralow fields is also demonstrated. Details of the circulating flow optical pumping apparatus and the SQUID spectrometer are presented. 相似文献
46.
M. Dülk ST. Fischer M. Bitter M. Caraccia W. Vogt E. Gini H. Melchior W. Hunziker A. Buxens H.N. Poulsen A.T. Clausen 《Optical and Quantum Electronics》2001,33(7-10):899-906
A monolithically integrated and fully packaged Mach–Zehnder interferometer with semiconductor optical amplifiers (MZI-SOA) is demonstrated as polarisation-independent high-speed demultiplexer for up to 160 Gbit/s optical time division multiplexed (OTDM) data streams. 相似文献
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Martin Bitter Sven Scharnowski Rainer Hain Christian J. Kähler 《Experiments in fluids》2011,50(4):1019-1030
High-repetition-rate PIV measurements were performed in the trisonic wind tunnel facility at the Bundeswehr University Munich
in order to investigate the boundary layer parameters on a generic rocket model and the recirculation area in the wake of
the model at Mach numbers up to Mach = 2.6. The data are required for the validation of unsteady flow simulations. Because
of the limited run time of the blow-down wind tunnel, a high-repetition-rate PIV system was applied to obtain the flow statistics
with high accuracy. The results demonstrate this method’s potential to resolve small-scale flow phenomena over a wide field
of view in a large Mach number range but also show its limitations for the investigations of wall-bounded flows. 相似文献
49.
Ildikó Mohammed-Ziegler Áron Szöllősy Miklós Kubinyi András Grofcsik Alajos Grün István Bitter 《Supramolecular chemistry》2013,25(6):415-421
Complexation of lithium ions by three chromoionophoric calix[4]arenes has been studied by 1H and 7Li NMR spectroscopy. The signalling unit of the chromoionophores is the N-methylpyridinium(methyleneimino) group in conjugation with a phenolic group of the calixarene ring while the coordination spheres contain esteric (ethoxycarbonylmethoxy) or etheric (ethoxy, propoxy) units. 1H NMR and NOESY measurements suggest the dominance of cone conformations of the calixarene rings with slight, solvent-dependent distortions. Complexation occurs only in the presence of a weak base. The interaction with lithium ions causes a broadening of both the 1H and 7Li NMR signals. Analysis of the chemical shifts in the three complexes indicates a different coordination environment for the lithium with the calixarene containing esteric groups from those having etheric groups. This explains the differences in the stabilities of the lithium complexes of the two types of calixarenes. 相似文献
50.
The Mitsunobu cyclization of p-t-butylthiacalix[4]arene with glycols was expanded to oligoethylene glycol analogues composed of O, S and N atoms in the chain. In this way a number of 1,3-thiacalix[4]monocrowns have been synthesized, offering simple and general access to a large variety of crowned thiacalixarenes. The binding properties of some ligands towards transition metal cations have been studied by 1H NMR, UV/Vis spectroscopic and potentiometric methods. 相似文献