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981.
982.
H. Sakai K. Hatanaka N. Matsuoka T. Saito A. Shimizu T. Motobayashi T. Shibata 《Physics letters. [Part B]》1983,133(6):375-379
The analyzing power of neutron continuum spectrum for the 93Nb(, nX) reaction at 65 MeV was measured for a wide angular range ?n = 20° – 130°. The analyzing powers are positive and large at large angles ?n > 40°. The characteristic features in the analyzing power for the 93Nb() reaction are very similar to those for the 93Nb(, p'X) reaction indicating the importance of a common reaction mechanism for both reactions. A DWBA calculation was performed and compared with the data. The calculation for EX = 14 MeV reproduced the cross sections but failed to reproduce the analyzing powers. 相似文献
983.
Kazuhiro Kawamura 《Proceedings of the American Mathematical Society》2002,130(2):609-611
We prove that every finitely generated group acts effectively on the universal Menger curve.
984.
985.
Kazuhiro Koike Geoffrey A. Cordell Norman R. Farnsworth Andrew A. Freer Christopher J. Gilmore George A. Sim 《Tetrahedron》1980,36(9):1167-1172
From the wood stem and stem bark of the Panamanian plant Rondeletia panamensis (Rubiaceae), three novel diterpenes have been isolated. The structure of oxidopanamensin (2) was determined by single crystal X-ray crystallography of the diacetate derivative. Panamensin (4) was correlated with oxidopanamensin (2) by epoxidation under alkali conditions and with rondeletin (6) by hydrogenation to 14,15-dihydrorondeletin (8). Of the three isolates, panamensin (4) and oxidopanamensin (2) were cytotoxic in the KB test system but rondeletin was inactive. 相似文献
986.
Yoshiro Sakai Machio Iwasaki 《Journal of polymer science. Part A, Polymer chemistry》1969,7(11):3143-3150
The anomalous crystalline transition of methacrylic acid found by broad-line NMR measurements was studied in connection with the build-up and decay of trapped radicals. The build-up of radicals is smaller and the decay rate of the trapped radicals is faster in the low-temperature range (phase II), which gave the narrower maximum slope distance ΔHmsl of the NMR spectrum, than those in the higher temperature range (phase I), which gave the broader ΔHmsl. From these experiments it was concluded that in phase I the crystals have a more closely packed structure, resulting in a more rigid matrix for the trapped radicals than those in phase II. This interpretation is consistent with the temperature dependence of the ESR spectrum of the trapped propagating radicals previously reported. The existence of the crystalline transition was also confirmed by DSC measurements, and the effects of the crystallization conditions on the transition were investigated and were discussed with reference to the results of broad line NMR measurements. 相似文献
987.
Kiyohisa Takahashi Masahiko Ikeda Kazuhisa Harakawa Kenji Tanaka Tetsuya Sakai 《Journal of Polymer Science.Polymer Physics》1978,16(3):415-425
An attempt was made to study the effect of interfacial slippage on the filler reinforcement based on the boundary condition that the constituents of a particle-filled composite can slip relative to each other, but no cavities are formed at the interfaces. The elastic field satisfying these conditions is derived using the linear theory of elasticity and the effective elastic moduli of the composite are calculated. The following assumptions are made: (1) Filler particles are spherical, (2) fillers are completely dispersed, and (3) the volume fraction of fillers is sufficiently small that the interaction among fillers may be neglected. The expression for the shear modulus of the composite μ**, which is derived here, is consistent with the viscosity of a suspension which has been derived by Oldroyd. Experiments who that the increase of Young's modulus by glass beads (GB) is lower in polystyrene (PS) than in epoxy resin (Ep). The reinforcement in Ep-GB systems can be estimated by the well known formula derived assuming perfect adhesion. However, the reinforcement in PS-GB systems is in rather good agreement with the formula derived here assuming interfacial slippage. 相似文献
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