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31.
The microwave spectrum of MnO3F has been remeasured and several corrections and new results have been obtained: B0 = 4129.141 MHz, DJ = 1.12 kHz, DJK = 1.87 kHz; , , , |q5| = 16.005, and |q6| = 8.456 MHz. 相似文献
32.
John C. Helmer 《Journal of Electron Spectroscopy and Related Phenomena》1973,1(3):259-267
The chemical shift in electron binding energy, magnetic splitting of electron shells, and structures in the valence band are examined for chromium in the 3 + and 6 + oxidation states.The splitting of the Cr 3s energy level is associated with the appearance of a sharp Cr 3d line in the valence band. The relative chemical shift in the Cr 2p line between Cr2O3 and K2Cr2O7 is verified in the mixed compound KCr3O8 which contains both types of Cr ions, and the structure of this compound is verified by the X-ray photoelectron spectra. The spin-orbit intensity ratio of the 2p doublet of Cr6+ is 3, instead of the theoretical value of 2, and the spin-orbit splitting is less than for Cr3+. In the 3p level of Cr the relative chemical shift is 3.5 eV whereas for the 2p level the shift is only 2.4 eV. The differences in chemical shift and intensity ratio can not be explained. 相似文献
33.
34.
Aliu E Andringa S Aoki S Argyriades J Asakura K Ashie R Berns H Bhang H Blondel A Borghi S Bouchez J Burguet-Castell J Casper D Cavata C Cervera A Cho KO Choi JH Dore U Espinal X Fechner M Fernandez E Fukuda Y Gomez-Cadenas J Gran R Hara T Hasegawa M Hasegawa T Hayashi K Hayato Y Helmer RL Hill J Hiraide K Hosaka J Ichikawa AK Iinuma M Ikeda A Inagaki T Ishida T Ishihara K Ishii T Ishitsuka M Itow Y Iwashita T Jang HI Jeon EJ Jeong IS Joo K Jover G Jung CK Kajita T Kameda J Kaneyuki K Kato I 《Physical review letters》2005,94(8):081802
We present results for nu(mu) oscillation in the KEK to Kamioka (K2K) long-baseline neutrino oscillation experiment. K2K uses an accelerator-produced nu(mu) beam with a mean energy of 1.3 GeV directed at the Super-Kamiokande detector. We observed the energy-dependent disappearance of nu(mu), which we presume have oscillated to nu(tau). The probability that we would observe these results if there is no neutrino oscillation is 0.0050% (4.0 sigma). 相似文献
35.
Ahmed SN Anthony AE Beier EW Bellerive A Biller SD Boger J Boulay MG Bowler MG Bowles TJ Brice SJ Bullard TV Chan YD Chen M Chen X Cleveland BT Cox GA Dai X Dalnoki-Veress F Doe PJ Dosanjh RS Doucas G Dragowsky MR Duba CA Duncan FA Dunford M Dunmore JA Earle ED Elliott SR Evans HC Ewan GT Farine J Fergani H Fleurot F Formaggio JA Fowler MM Frame K Fulsom BG Gagnon N Graham K Grant DR Hahn RL Hall JC Hallin AL Hallman ED Hamer AS Handler WB Hargrove CK Harvey PJ Hazama R Heeger KM Heintzelman WJ 《Physical review letters》2004,92(18):181301
The Sudbury Neutrino Observatory has precisely determined the total active (nu(x)) 8B solar neutrino flux without assumptions about the energy dependence of the nu(e) survival probability. The measurements were made with dissolved NaCl in heavy water to enhance the sensitivity and signature for neutral-current interactions. The flux is found to be 5.21 +/- 0.27(stat)+/-0.38(syst) x 10(6) cm(-2) s(-1), in agreement with previous measurements and standard solar models. A global analysis of these and other solar and reactor neutrino results yields Deltam(2)=7.1(+1.2)(-0.6) x 10(-5) eV(2) and theta=32.5(+2.4)(-2.3) degrees. Maximal mixing is rejected at the equivalent of 5.4 standard deviations. 相似文献
36.
Refractive index measurements by probe-beam deflection 总被引:1,自引:0,他引:1
G.?T.?Purves G.?Jundt C.?S.?Adams I.?G.?HughesEmail author 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2004,29(3):433-436
Two deflection techniques for the measurement of the dispersive properties of an optical medium have been implemented. Prismatic deflection is used to measure the dispersion of a medium exhibiting Electromagnetically Induced Transparency (EIT) with the
cascade system in 85Rb and 87Rb. In addition, the dispersion associated with a saturated absorption and hyperfine pumping spectrum is measured by deflection due to a spatial inhomogeneity of the refractive index induced by an expanded Gaussian-profile pump beam.Received: 19 December 2003, Published online: 20 April 2004PACS:
39.30. + w Spectroscopic techniques - 33.55.Ad Optical activity, optical rotation; circular dichroismG. Jundt: Present address: Institute of Quantum Electronics, Department of Physics, ETH Zürich, Hönggerberg 8093, Switzerland 相似文献
37.
Here we consider, in a principally ordered regular semigroup in which the operation
$x \mapsto x*$ is weakly isotone, the structure of the *-subsemigroup that is
generated by a pair of comparable idempotents. 相似文献
38.
Wan H Holmén AG Wang Y Lindberg W Englund M Någård MB Thompson RA 《Rapid communications in mass spectrometry : RCM》2003,17(23):2639-2648
A high-throughput pKa screening method based on pressure-assisted capillary electrophoresis (CE) and mass spectrometry (MS) is presented. Effects of buffer type and ionic strength on sensitivity and pKa values were investigated. Influence of dimethyl sulfoxide (DMSO) concentration present in the sample on effective mobility measurement was examined. A series of ten volatile buffers, covering a pH range from 2.5 to 10.5 with the same ionic strength, was employed. The application of volatile background electrolytes resulted in significant signal increase as compared with commonly used non-volatile phosphate buffers. In general, the CE/MS system provided a ten-fold higher sensitivity than conventional UV detection. The newly developed CE/MS method offers high-throughput capacity by pooling a number of compounds into a single sample. Simultaneous measurement of more than 50 compounds was readily achieved in less than 150 min. The measured pKa values are consistent with the published data obtained from the CE/UV method and are also in good agreement with data generated by other methods. Other advantages of using CE/MS for pKa screening are illustrated with typical examples, including poorly soluble compounds and non-UV-absorbing compounds. 相似文献
39.
G.?JundtEmail author G.?T.?Purves C.?S.?Adams I.?G.?Hughes 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,27(3):273-276
We explore pump-probe non-linear Sagnac interferometry as a tool to measure the dispersive properties of a medium. We introduce the background theory, and show experimental spectra obtained on the D2 transition with 85Rb and 87Rb. The measured dispersion spectra are in excellent agreement with the Kramers-Kronig relations. In addition, as both beams traverse identical optical paths, Sagnac interferometry is very robust against mechanical vibrationReceived: 5 June 2003, Published online: 16 September 2003PACS:
39.30. + w Spectroscopic techniques - 33.55.Ad Optical activity, optical rotation; circular dichroismG. Jundt: Present address: Institute of Quantum Electronics, Department of Physics, ETH Zürich, Hönggerberg 8093, Switzerland. 相似文献
40.
Han S Gemmell SJ Helmer KG Grigg P Wellen JW Hoffman AH Sotak CH 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2000,144(2):217-227
Water diffusion measurements were performed on rabbit Achilles tendons during static tensile loading and tendons in an unloaded state. The apparent diffusion coefficient (ADC) was measured along two directions: parallel and perpendicular to the long axis of the tendon. Tendons were studied after being prepared in two ways: (a) after being stored frozen in phosphate-buffered saline (PBS) and (b) freshly isolated. Statistically significant directional anisotropy was observed in the ADC in all tendons. The ADC was significantly greater in the direction parallel to the long axis of the tendon than in the perpendicular direction. The anisotropy is attributed to the greater restrictions seen by the water molecules in the perpendicular direction and is consistent with the known geometry of the tendon. Storage in PBS caused tendons to swell. This increased the ADC measured along both directions and reduced the anisotropy. The existence of anisotropy in the ADC was not related to the orientation of the specimen in the magnet. The ADC increased along both directions following the application of a 5-N tensile load; the increase was greatest along the perpendicular axis of the tendon. In order to determine whether load-related changes in the ADC reflected changes in interfibrilar spacing, we used electron microscopy to measure load-related changes in fibril spacing. Load-related changes in fiber spacing could not account for the observed changes in the ADC. The increase in ADC caused by loading was attributed to the extrusion of tendon water into a bulk phase along the outside surface of the tendon. In PBS-stored samples, enough fluid was extruded that it could be visualized. The transient response of the ADC to a 5-N tensile load was also studied. The absolute ADC in both directions increased with loading and recovered to baseline upon unloading. The transient changes in ADC, for both loading and unloading, had a mean time constant of approximately 15 min. The magnitude of the load-induced transient ADC changes was comparable to that seen in the static-loading experiments. 相似文献