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31.
Masazumi Ishiguro Kensuke Harada Keiichi Tanaka Takehiko Tanaka 《Journal of Molecular Spectroscopy》1996,180(2)
Rotational transitions of fluoroacetylene in the ν1(CH stretch) vibrational state have been observed by the laser–microwave double resonance technique using a color center laser as a radiation source in the 3 μm region. The rotational constant and centrifugal distortion constant in the ν1state were determined to be 9684.310(16) MHz and 2.68(62) kHz, respectively, where the uncertainties given in parentheses correspond to 2.5 standard deviations. 相似文献
32.
M. Musha Y. Sato K. Nakagawa K. Ueda A. Ueda M. Ishiguro 《Applied physics. B, Lasers and optics》2006,82(4):555-559
We have developed an optical fiber length stabilization system for the distribution of reference millimeter wave signals in a long-baseline phased-array radio telescope. The fiber length was compared with an absolute wavelength reference laser using a Michelson interferometer. We used a digital servo system including a digital phase-frequency discriminator with a wide phase dynamic range and a digital signal processor (DSP) for the digital servo system. All-digital servo system made it possible to realize a robust and precise length stabilization of a 25-km long optical fiber. PACS 42.62.Eh; 42.81.Uv; 95.55.Jz 相似文献
33.
Akifumi Yafune Toshiki Matsubara Makio Ishiguro 《Annals of the Institute of Statistical Mathematics》1993,45(3):401-418
For the treatment of patients with cancer of the thoracic esophagus, lymphatic spreading is one important factor to infer how advanced their cancer is. We introduced a one-dimensional scale based on lymphatic spreading patterns, the stage of cancer, to express how advanced their cancer is, and we proposed a method to infer each patient's stage from his lymphatic spreading pattern by applying a Bayesian model. Our Bayesian model was built based on the assumption that lymphatic spreading in cancer could be explained as what was brought about by the advance of stage. In the modeling, we introduced the probability of what stage each patient was in as a prior distribution. We also introduced distribution functions of Weibull distributions to express the relation between the advance of stage and the increase of the probability of metastasis. Our model was applied to the data of nodal involvement obtained from 103 patients with cancer of the thoracic esophagus and the parameters were estimated with the maximum likelihood method. AIC was used to check that the data had enough information to be divided into the stages of a clinically reasonable number. With the estimated parameters, we inferred the probability of metastasis to each lymph node in each stage and calculated by Bayes' theorem with 31 new patients the probability of what stage they were in. The results well represented some characteristics of the lymphatic spreading and suggested the appropriateness of our approach.The present study was carried out under the ISM Cooperative Research Program (91-ISM·CRP-18). 相似文献
34.
Sensitized photooxidation of alkylphenyldiazomethanes under oxygen afforded, in addition to alkyl phenyl ketones, alkyl benzoates, which are probably formed by a rearrangement via dioxirane diradical. 相似文献
35.
Katsuya Ishiguro Kohtaro Tomizawa Yasuhiko Sawaki Hiizu Iwamura 《Tetrahedron letters》1985,26(31):3723-3726
A tracer study for the rearrangement of carbonyl oxides to esters using doubly-labeled oxygen lead to a conclusion that carbonyl oxides do not isomerize directly to dioxyranes and the rearrangement to esters proceeds via a cyclic tetroxide. 相似文献
36.
K. Kajimura H. Tokumoto M. Tokumoto K. Murata T. Ukachi H. Anzai T. Ishiguro G. Saito 《Solid State Communications》1982,44(12):1573-1576
Successive transitions from metal to the spin-density-wave (SDW) state and the three-dimensional superconducting (3D-SC) state were found in thermally quenched bis-tetramethyltetraselenafulvalenium perchlorate, (TMTSF)2ClO4. The SDW state was suppressed after the sample was warmed above ~25 K and cooled slowly. The appearance of the SDW state in addition to the 3D-SC state in the quenched sample is interpreted by the decrease in interchain coupling which could result from the thermal quenching of a high temperature configuration with disordered (ClO4)-anions. The effect of thermal quenching on quantum oscillations in transverse magnetoresistance was also studied. 相似文献
37.
Umebayashi Y Mroz B Asada M Fujii K Matsumoto K Mune Y Probst M Ishiguro S 《The journal of physical chemistry. A》2005,109(21):4862-4868
Solvation structure of the zinc(II) ion in N,N-dimethylpropionamide (DMPA) was studied by Raman spectroscopy at varying temperature and by quantum mechanical calculations. No significant ion-pair formation was found for the Zn(ClO4)2 solution in the molality range m(Zn) < 1.5 mol kg(-1), and the solvation number of the zinc(II) ion was determined to be 4, indicating that 6-coordination of DMPA is sterically hindered. Interestingly, DMPA molecules are under equilibrium between planar cis and nonplanar staggered conformers, and the latter is more preferred in the coordination sphere, while the reverse is the case in the bulk. The DeltaG degrees , DeltaH degrees , and TDeltaS degrees values of conformational change from planar cis to nonplanar staggered in the coordination sphere were obtained to be -0.9, -8.5, and -7.5 kJ mol(-1), respectively. Density functional theory (DFT) calculations show that the planar cis conformer is more favorable than the nonplanar staggered one in the 1:2 cluster, as is the case for a single DMPA molecule and H(DMPA)+, indicating that there hardly occurs solvent-solvent interaction through the metal ion in the Zn2+-DMPA 1:2 cluster. On the other hand, the SCF energy of [Zn(planar cis-DMPA)4-n(nonplanar staggered DMPA)n]2+ (n = 0-4) decreases with increasing n, implying that the nonplanar staggered conformer is preferred in the solvate ion. It is thus concluded that solvent-solvent interaction through space, or solvation steric effect, plays a crucial role in the conformational equilibrium in the coordination sphere of the four-solvate metal ion. 相似文献
38.
S. Kagoshima T. Ishiguro E.M. Engler T.D. Schultz Y. Tomkiewicz 《Solid State Communications》1980,34(3):151-155
In the quasi one-dimensional conductor TTF0.4TSeF0.6-TCNQ, it is found that the 2kF CDW has three-dimensional correlations of relatively long range below the metal-insulator transition temperature ~40K, although the 4kF CDWs are only one-dimensional in character at all temperatures. This result supports the speculation that the 2kF CDWs and the 4kF CDWs are present predominantly on the TCNQ and the fulvalene stacks, respectively. The 2kF-value of the present material is similar to that of TTF-TCNQ but far from that of TSeF-TCNQ. The change of the value with the concentration of TSeF (or TTF) is nonlinear. The transverse period of the ordered 2kF CDW along the a-axis is just below the transition temperature and becomes 4 below 34.5K. A discussion is given based on the two-chain model. 相似文献
39.
40.
The temperature dependences of the elastic constants, c11, c33, c44, and c66, in KCP are described. In the temperature range 10–100 K softening is observed in c44, while c66 decreases almost linearly with decreasing temperature. These results indicate the presence of a new critical region. 相似文献