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91.
92.
The reaction of phenylselenenyl chloride with olefins in aqueous acetonitrile affords β-hydroxyalkyl phenyl selenides in excellent yields, providing the most convenient method for hydroxyselenation of olefins so far reported. When the reaction was applied to conjugated dienes, monohydroxyselenated products were obtained in good to excellent yields. From non-conjugated dienes, on the other hand, cyclic ethers containing two phenylseleno groups were produced in good to excellent yields, the first step of this reaction being the hydroxyselenation of one double bond.  相似文献   
93.
Total cross sections for single-electron capture by He+ ions in vapor targets of Cs, Rb, K and Na have been determined in the energy range 0.4–5.0 keV. The energy dependence of the cross-section curves is very similar for all the targets. The cross sections for all the targets are maximum at about the same energy, 1.5 keV. Comparison is made with other reported experimental and theoretical results.  相似文献   
94.
Mader proved that for every k-edge-connected graph G (k ≥ 4), there exists a path joining two given vertices such that the subgraph obtained from G by deleting the edges of the path is (k - 2)-edge-connected. A generalization of this and a sufficient condition for existance of 3, 4, or 5 terminus k edge-disjoint paths in graphs are given.  相似文献   
95.
The author traces the encounter of μSR physicists with the Kubo–Toyabe theory and the subsequent development of zero‐field μSR by mutual communication between experiment and theory. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
96.
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98.
The ensemble-averaged spatial coherence of quasi-thermal light, produced by passing a focused laser beam through a rotating ground glass plate, is studied as a function of the illuminated area, the fineness of the glass used, the speed of rotation of the glass, and the laser mode selected as a primary source. It becomes clear that the ensemble-averaged spatial coherence depends strongly upon the illuminated area and on the fineness of the rotating ground glass, and also on the laser mode chosen but not on the speed of rotation of the glass.  相似文献   
99.
100.
The equations of motion of a test particle moving near the center of a massive rotating ring are derived up to the post-post-Newtonian order of approximation, by using the metric tensor for many body system which is Minkowskian at spatial infinity. Logarithmic divergences due to self-interaction of the ring appear in the equations of motion. These divergences can be removed by the procedure which is similar to the renormalization method in particle physics. In the equations of motion there appears a force directing to the rotation axis and depending on the angular velocity of the ring. This force vanishes when the magnitude of the gravitational constant times the mass of the ring divided by the radius of the ring is about one tenth of the square of the velocity of light. Under this condition it is shown that the relative magnitude of the Coriolis force to the centrifugal force in the equations of motion agrees with the expected one from the equations of motion in a rotating reference frame.  相似文献   
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