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51.
Emanuela Locci Yves Dehouck Mariano Casu Giuseppe Saba Adolfo Lai Michel Luhmer Jacques Reisse Kristin Bartik 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2001,150(2):167
The interaction of xenon with different proteins in aqueous solution is investigated by 129Xe NMR spectroscopy. Chemical shifts are measured in horse metmyoglobin, hen egg white lysozyme, and horse cytochrome c solutions as a function of xenon concentration. In these systems, xenon is in fast exchange between all possible environments. The results suggest that nonspecific interactions exist between xenon and the protein exteriors and the data are analyzed in term of parameters which characterize the protein surfaces. The experimental data for horse metmyoglobin are interpreted using a model in which xenon forms a 1:1 complex with the protein and the chemical shift of the complexed xenon is reported (Locci et al., Keystone Symposia “Frontiers of NMR in Molecular Biology VI”, Jan. 9–15, 1999, Breckenridge, CO, Abstract E216, p. 53; Locci et al., XeMAT 2000 “Optical Polarization and Xenon NMR of Materials”, June 28–30, 2000, Sestri Levante, Italy, p. 46). 相似文献
52.
Jacques Bros 《Communications in Mathematical Physics》2003,237(1-2):289-308
It is proved that in any massive relativistic quantum field theory satisfying two-particle asymptotic completeness, all the
bounded energy components in the elastic two-particle range of all subsets of states which are excitations of the vacuum state
by uniformly bounded observables localized in a given finite region of spacetime are compact in the Hilbert space of states.
This result, which is in agreement with Haag-Swieca's conjecture, is also given a more precise form in terms of the rate of
decrease of the ``N–dimensional thickness' (or approximation number) of such sets of states when N tends to infinity. A similar computation, valid at arbitrarily high energies, is also given for the massive free-field case.
Received: 7 February 2003 / Accepted: 5 April 2003
Published online: 13 May 2003
Communicated by H. Araki, D. Buchholz and K. Fredenhagen 相似文献
53.
Chalcogenide glass fibers have been successfully used for remote spectroscopy, temperature sensing and CO2 laser power delivery. In bulk form, chalcogenide glass is the most promising candidate for replacing the expensive germanium lenses for thermal imaging. 相似文献
54.
Ghislain Blanquet Jacques Walrand Irne Hilgers Daniel Lambot 《Journal of Molecular Spectroscopy》1990,140(2)
A tunable diode laser was used to perform measurements of absolute lines intensities in the ν1 fundamental of carbonyl sulfide. Spectra have also been recorded for the following isotopic species: 16O12C34S, 16O13C32S and 16O12C33S. The vibrational band strength Sv0 was calculated at 298 K. The absolute intensity for 100% of 16O12C32S species is found to be Sv0 = 29.69 ± 0.15 cm−2 atm−1 with the uncertainty covering three times the standard deviation. We have tried to determine the α-coefficient involved in the Hermann-Wallis factor F = (1 + αm + )2 and the value is found to be negligible (−5 ± 8) × 10−5. The Sv0 value obtained for the other isotopic species is very close to the normal one. 相似文献
55.
Brick DH Widgoff M Beilliere P Lutz P Narjoux JL Gelfand N Alyea ED Bloomer M Bober J Busza W Cole B Frank TA Fuess TA Grodzins L Hafen ES Haridas P Huang D Huang HZ Hulsizer R Kistiakowsky V Ledoux RJ Milstene C Noguchi S Oh SH Pless IA Steadman S Stoughton TB Suchorebrow V Tether S Trepagnier PC Wadsworth BF Wu Y Yamamoto RK Cohn HO Calligarich E Castoldi C Dolfini R Introzzi G Ratti S Badiak M DiMarco R Jacques PF Kalelkar M Plano RJ Stamer PE Brucker EB Koller EL Alexander G Grunhaus J 《Physical review D: Particles and fields》1990,41(3):765-773
56.
57.
Othman Belhadj Miled David Grosso Jacques Livage 《Journal of Physics and Chemistry of Solids》2004,65(10):1751-1755
This paper describes the synthesis and optical pH sensing properties of a pH indicator dye activated mesostructured silica coated optical fibre. The pH-sensitive dye bromothymol blue was incorporated into the mesostructure sol precursor and thin films/coatings were used for pH-sensing applications without prior removal of the surfactant. The pH sensitivity range and operating wavelength were analysed by absorption measurements on layer dip-coated on glass slides. The pH sensing properties of coated optical fibre were tested by evanescent wave method. Experiments were carried out by using a series of solutions of known pH. No leaching was observed (except at very high pH) and an excellent reversibility was obtained between pH=2 and 5. 相似文献
58.
Merlet D Béguin L Courtieu J Giraud N 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2011,209(2):315-322
The application of the G-SERFph pulse sequence is presented on enantiomeric mixtures dissolved in a chiral liquid crystal. It aims at editing, within one single 2D spectrum, every proton coupling which is experienced by a given proton site in the molecule, and leads to real phased T-edited spectroscopy (T=J+2D). This NMR experiment is based on the combination of homonuclear semi-selective refocusing techniques with a spatial frequency encoding of the sample. This approach, which consists in handling selectively each coupling in separate cross sections of the sample, is applied to the visualization of enantiomers dissolved in a chiral liquid crystalline phase. Advantages and limits of this methodology are widely discussed. 相似文献
59.
60.
A very compact 3-D range sensor for robot and vehicle guidance is described. A dual aperture mask in a camera lens is used to transform a small commercially available CCD video camera into a ranging sensor. An active system using a projected laser beam provides a 360° range map which can be used to plan trajectories, either for robots or autonomous vehicles. Good quality panoramic intensity and 3-D images were obtained. Accuracy, speed of acquisition, and cost are discussed. Experimental results are presented. 相似文献