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61.
62.
Yoshihisa Kitazawa 《Physics letters. [Part B]》1985,151(2):165-170
We compare the PCAC prediction based on the chiral anomaly for the π0 lifetime with a recent experiment. We find that the QED corrections are as large as 3%. After these corrections the experiment and the PCAC prediction disagree by 8.5 ± 2%. We estimate the corrections to the PCAC prediction. We find that reliably calculable corrections are not large enough to account for the discrepancy. However, contributions from the excited π0's may be able to explain the difference. 相似文献
63.
Takafumi Isogai 《Annals of the Institute of Statistical Mathematics》1985,37(1):289-301
Summary Some extension of Haldane's multivariate median is carried out by minimization principle of a specified distance function.
Then, making use of the median, three types of measures of multivariate skewness are introduced and their asymptotic null
distributions are obtained. 相似文献
64.
Tri-O-benzoyl and tri-O-acetyl derivatives of the title compound are obtained from the corresponding 1-O-acetates in good yields by treatment with cyanotrimethylsilane. 相似文献
65.
In order to determine the copper content x of copper Chevrel compound CuxMo6S8?y(0?y?0.4) as a function of copper activity aCu and sulfur deficit y, a solid state electrochemical cell, Cu/Rb4Cu16I7Cl13/CuxMo6S8?y/Pt, was constructed and coulometric titration studies were made at 400 K. For the evaluation of the coulometric titration data, measurements were made on the electronic conductivity of copper-ion conductor Rb4Cu16I7Cl13. Also, a brief investigation was made on the condition of formation of single phase Chevrel CuxMo6S8?y with varying x and y at 1000°C. The structural change of CuxMo6S8?y with a change in x and y was studied by the X-ray diffraction method. It was found that x for constant aCu decreases with increasing y. The maximum value xmax of x in CuxMo6S8?y in equilibrium with metallic copper was found to be expressed by . In the region of y<0.3, xmax exceeded 4, contrary to a presupposition that xmax is less than 4. X-ray analysis revealed that most of the copper Chevrel compounds denoted by CuxMo6S8 so far were sulfur deficient ones with y?0.4. The importance of sulfur deficit on the properties of the copper Chevrel compound was emphasized. 相似文献
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Aizawa T Kanakubo M Hiejima Y Ikushima Y Smith RL 《The journal of physical chemistry. A》2005,109(33):7353-7358
Local density augmentation around exciplex between acetophenone and N,N,N',N'-tetramethylbenzidine in supercritical water was measured by observing the peak shift of transient absorption spectrum at temperatures from 380 to 410 degrees C and at pressures from 6 to 37 MPa. Large local density augmentation was observed at lower solvent densities. Local density augmentation was evaluated by the excess density, which was defined as the difference between local density and bulk density, and the density enhancement factor, which was defined by the ratio of the local density to the bulk density. The number of solvating molecules was estimated with a Langmuir adsorption model. The excess density was found to exhibit a maximum at approximately 0.15 g cm(-3), which decreased with increasing temperature. The density enhancement factor was found to decrease with increasing temperature; however, its value was much greater than unity at 410 degrees C, which provides evidence that exciplex-water interactions still exist at these conditions. The temperature dependence of local density augmentation around the exciplex in supercritical water was comparable with that in supercritical carbon dioxide, which suggests that the ratios of the solute-solvent and solvent-solvent interactions are comparable between these two systems. 相似文献