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101.
The statistical properties of speckle intensity variations produced by coherent light in the diffraction field of diffusely transmitting objects are investigated experimentally with intimate relation to their surface roughness. The probability distribution and the average contrast of intensity variations in speckle patterns are studied as a function of the surface roughness of the objects and the receiving plane in the diffraction field. 相似文献
102.
103.
104.
Yosuke Ohkura Kenji Ohtsubo Kiyoshi Zaitsu Kazuya Kohashi 《Analytica chimica acta》1978,99(2):317-324
A sensitive fluorimetric method for the determination of aromatic aldehydes is based on their reaction in dilute sulfuric acid with a new reagent, 2,2'-dithiobis(l-amino-naphthalene) in the presence of tri-n-butylphosphine, sodium sulfite and sodium phosphite at ambient temperature. The fluorescences produced are fairly characteristic of individual aldehydes. The method is extremely selective for aromatic aldehydes and very sensitive, especially for p-hydroxybenzaldehyde, o-methoxybenzaldehyde, p-methoxybenzaldehyde and p-tolualdehyde which can be determined at concentrations of as little as 3–5 ng ml-1. 相似文献
105.
106.
Junji Ohtsubo 《Optics Communications》1980,34(2):147-152
The vector velocity measurement of the in-plane object motion based on the dynamic properties of speckle patterns is conducted. The time-space cross-correlation function of speckle intensity variations is used to determine the magnitude and direction of the in-plane object velocity. Theoretical and experimental studies of the speckle correlation technique for the determination of the in-plane object velocity are discussed and the vector velocities of the diffuse object are displayed as a two-dimensional image. 相似文献
107.
In order to investigate spectral shape factors of 12B and 12N, we make a new formalism of β-decay theory, where the radial wave functions of leptons are treated with no approximation and, therefore, the nuclear matrix elements are electron-energy dependent. With this formalism we can show strong support for the conserved vector current hypothesis in analyzing the experimental data which were given by Wu, Lee and Mo in 1963 and revised by them in 1977 using the latest experimental results on the end-point energies and branching ratios of the inner β-groups, in addition to the correct Fermi functions for the positron. In fact, the average slopes of the spectral shape factors for 12B and 12N are in excellent agreement with those in our theory. Recent experimental data given by the Heidelberg group are also in good agreement with the theory if we analyze the difference of the average slopes for 12B and 12N. There are, however, small discrepancies with the theory in their individual values. The relation of the present formalism with traditional theories of β-decay is discussed. 相似文献
108.
We made an explicit formula for beta-ray angular distribution by taking into account the radiative corrections, Coulomb corrections of the finite-size nucleus, weak magnetism, induced pseudoscalar, second-class induced tensor, and contributions of the d-wave leptons. Experimental data on the beta decays of aligned 12B and 12N given at Osaka are carefully investigated, and it is shown that these data are compatible with no induced tensor current, . The nuclear parameter y is 3.3±0.9 in excellent agreement with the predicted value 3.6. 相似文献
109.
M. Mihara T. Izumikawa H. Ueno K. Matsuta D. Nishimura T. Nagatomo T. Moriguchi Y. Ito D. Nagae M. Fukuda A. Yoshimi K. Yamada M. Takechi Y. Ichikawa S. Momota Y. Hirayama T. Ohtsubo S. Suzuki T. Kubo Y. Namiki A. Ozawa Y. Ishibashi H. Oishi K. Suzuki I. Hachiuma K. Namihira D. Horikawa T. Minamisono T. Yamaguchi T. Kuboki T. Suzuki K. Satoh Y. Kobayashi K. Asahi K. Matsukawa K. Shirai 《Hyperfine Interactions》2010,197(1-3):143-147
The β-NMR study of short-lived nucleus 58Cu (I π ?=?1?+?, T 1/2?=?3.2 s) in Si has been performed. Spin polarization of 58Cu induced by the charge exchange reaction of 58Ni was observed in Si at 15 K. The 58Cu magnetic moment $|\upmu[^{58}\mbox{Cu}]| = (0.46 \pm 0.03)\upmu_{\rm N}$ deduced from the β-NMR spectrum is consistent with the previous results on the laser spectroscopy. The present result shows that the 58Cu nucleus is promising as a new nuclear probe for the microscopic study of Cu impurities in Si. 相似文献
110.
In the anomaly-mediated supersymmetry (SUSY) breaking scenario, neutral gaugino of SUL(2) multiplet, Wino, can be the lightest SUSY particle and become a candidate for dark matter. We calculated scattering cross section of Wino dark matter with nucleon, which is responsible for direct detection of the dark matter, on the assumption that the SUSY particles and the heavier Higgs bosons have masses of the order of the gravitino mass in the SUSY standard model. In such a case, the Wino–nucleon coupling is generated by loop processes. We have included two-loop contribution to Wino–gluon interaction in the calculation, since it is one of the leading contributions to the Wino–nucleon coupling. It was found that the spin-independent scattering cross section with proton is 10−(46–48) cm2. While it is almost independent of the Wino mass, the result is quite sensitive to the Higgs boson mass due to the accidental cancellation. 相似文献