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41.
Elizabeth K. Heaney S.R. Logan William E. Watts 《Journal of organometallic chemistry》1978,150(2):309-319
The anions of 4-([3]ferrocenophanyl)butanoic acids (Id and IId), when excited by light of around 240 nm wavelength in aqueous solution in the presence of N2O, undergo photo-oxidation to zwitterions (III and IV respectively) in a manner completely analogous to the reaction of 4-ferrocenylbutanoate anion. The differences in the kinetic parameters of the reactions are thought to be attributable in part to slight tilting of the cyclopentadienyl rings caused by the connecting trimethylene bridge. 相似文献
42.
David G. Watts 《General Relativity and Gravitation》2003,35(10):1799-1813
An infinite class of magnetized line-source (wire) metrics are here derived within the 5D GR (Kaluza-Klein) formalism. These metrics are cylindrically-symmetric (thus representing line-sources), and off-diagonal (thereby representing magnetized wire sources). The off-diagonality of these metrics is significant as all prior cylindrically-symmetric 5D GR metrics have been diagonal. In Kaluza-Klein theory, the vector potentials of EM are incorporated into the extended off-diagonal components of the metric. Thus, examination of such off-diagonal line source (magnetized wire) metrics is a hitherto untapped potential for 5D GR investigation. 相似文献
43.
It has become apparent that many intracellular signaling processes involve the dynamic reorganization of cellular proteins into complex signaling assemblies that have a specific subunit composition, function, and subcellular location. Since the elements of such assemblies interact physically, multiprotein signaling complexes can be isolated and analyzed. Recent technical advances in highly sensitive protein identification by electrospray-tandem mass spectrometry have dramatically increased the sensitivity with which such analyses can be performed. The T-cell antigen receptor (TCR) is an oligomeric transmembrane protein complex that is essential to T-cell recognition and function. The extracellular protein domains are responsible for ligand binding while intracellular domains generate and transduce signals in response to specific receptor-ligand interactions. We used microbore capillary chromatography-tandem mass spectrometry to investigate the composition of the TCR protein complex isolated from resting and activated cells of the murine T-cell line CD11.3. We identified all the previously known subunits of the TCR/CD3 complex as well as proteins previously not known to associate with the TCR. The catalytic activities of some of these proteins could potentially be used to interfere pharmacologically with TCR signaling. 相似文献
44.
Ukegawa F Valls J Vejcik S Velev G Vidal R Vilar R Vologouev I Vucinic D Wagner RG Wagner RL Wahl J Wallace NB Walsh AM Wang C Wang CH Wang MJ Watanabe T Watts T Webb R Wenzel H Wester WC Wicklund AB Wicklund E Williams HH Wilson P Winer BL 《Physical review letters》2000,84(2):232-237
We report a measurement of the fraction of b quarks produced diffractively in &pmacr;p collisions at sqrt[s] = 1.8 TeV. Diffraction is identified by the absence of particles in a forward pseudorapidity region. From events with an electron of transverse momentum 9.5
相似文献
45.
Toyoda H Trischuk W de Troconiz JF Tseng J Turini N Ukegawa F Vaiciulis T Valls J Vejcik S Velev G Vidal R Vilar R Volobouev I Vucinic D Wagner RG Wagner RL Wahl J Wallace NB Walsh AM Wang C Wang CH Wang MJ Watanabe T Waters D Watts T Webb R 《Physical review letters》2000,84(22):5043-5048
We report results from a study of events with a leading antiproton of beam momentum fraction 0.9057 GeV. Using the dijet events, we evaluate the diffractive structure function of the antiproton and compare it with expectations based on results obtained in diffractive deep inelastic scattering experiments at the DESY ep collider HERA. 相似文献
46.
Accurate control of vocal pitch (fundamental frequency) requires coordination of sensory and motor systems. Previous research has supported the relationship between perceptual accuracy and vocal pitch matching accuracy. The purpose of this study was to investigate the role of memory for pitch in pitch matching and pitch discrimination ability. Three experimental tasks were used. First, a pitch matching task was completed, in which the participants listened to target tones and vocally matched the pitch of the tones. The second task was a pitch discrimination task that required the participants to judge the pitch (same or different) of complex tone pairs. The third task was pitch discrimination with memory interference task that was similar to the pitch discrimination task except interference tones were added. Results of the pitch matching and pitch discrimination tasks yielded a significant correlation between these values. When there was memory interference, pitch discrimination ability was poorer, and there was no significant correlation between pitch discrimination and pitch matching. These results support earlier findings of a relationship between pitch discrimination and pitch matching abilities. The results also suggest a possible role of pitch memory in both tasks. These findings may have implications for abilities related to accurate pitch control. 相似文献
47.
S. Barlag H. Becker T. Böhringer M. Bosman V. Castillo V. Chabaud D. Buchholz C. Damerell C. Daum H. Dietl H. Fawcett S. Gill A. Gillman R. Gilmore T. Gooch L. Görlich P. Gras Z. Hajduk E. Higon B. D. Hyams D. P. Kelsey J. Kemmer R. Klanner U. Kötz S. Kwan B. Lücking G. Lütiens G. Lutz J. Malos W. Männer E. Neugebauer H. Palka M. Pepé J. Richardson G. De Rijk K. Rybicki H. J. Seebrunner U. Stierlin H. G. Tiecke M. Turala G. Waltermann S. Watts P. Weilhammer F. Wickens L. W. Wiggers A. Wylie T. Zeludziewicz ACCMOR Collaboration 《Zeitschrift fur Physik C Particles and Fields》1987,37(1):17-23
We have measured the lifetimes of hadronically produced charged and neutralD mesons using silicon microstrip detectors and an active silicon target in the NA32 spectrometer at the CERN SPS. We obtainτ D± = (10.9± 1.5 1.9 )·10?13s andτ D (?)10 = (4.2±0.5)·10?13s based on 59 and 90 fully reconstructed decays respectively, giving a ratioτ D±/τ D (?)10 of 2.6 ±0.5. 相似文献
48.
The algebra dual to Woronowicz's deformation of the two-dimensional Euclidean group is constructed. The same algebra is obtained from SU
q
(2) via contraction on both the group and algebra levels. 相似文献
49.
50.
D. G. Middleton J. R. M. Annand C. Barbieri P. Barneo P. Bartsch D. Baumann J. Bermuth D. Bosnar H. P. Blok R. Böhm M. Ding M. O. Distler D. Elsner J. Friedrich C. Giusti D. I. Glazier P. Grabmayr S. Grözinger T. Hehl J. Heim W. H. A Hesselink E. Jans F. Klein M. Kohl L. Lapikás I. J. D. MacGregor I. Martin J. C. McGeorge H. Merkel P. Merle F. Moschini U. Müller Th. Pospischil G. Rosner H. Schmieden M. Seimetz A. Süle H. de Vries Th. Walcher D. P. Watts M. Weis B. Zihlmann 《The European Physical Journal A - Hadrons and Nuclei》2006,30(2):469-469