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71.
72.
Symbolic dynamics is applied to the one-dimensional three-body problem with equal masses. The sequence of binary collisions along an orbit is expressed as a symbol sequence of two symbols. Based on the time reversibility of the problem and numerical data, inadmissible (i.e., unrealizable) sequences of collisions are systematically found. A graph for the transitions among various regions in the Poincare section is constructed. This graph is used to find an infinite number of periodic sequences, which implies an infinity of periodic orbits other than those accompanying a simple periodic orbit called the Schubart orbit. Finally, under reasonable assumptions on inadmissible sequences, we prove that the set of admissible symbol sequences forms a Cantor set. (c) 2000 American Institute of Physics. 相似文献
73.
Yun-Qi Liu Dao-Ben Zhu Li-Ke Ruan Chun-Li Bai Akira Yamada Kiyotaka Shigehara 《中国化学》1991,9(2):126-130
Three different kinds of rare-earth metal phthalocyanine complexes (Pc2LuH, Pc3Gd2, R12 Pc3Dy2) were synthesized. Their ultra-thin films were prepared by the Langmuir-Blodgett technique. Crystallites were observed in Langmuir film of Pc3Gd2 by means of transmission electron microscopy. The limiting molecular areas of the phthalocyanine derivatives on pure water increased in the order mono-, di- and triphthalocyanine, implying that these phthalocyanine molecules are stacked with a face-to-face orientation and edge-on to the water surface. By using scanning tunneling microscopy individual molecules of lutetium diphthalocyanine adsorbed on graphite surfaces were imaged for the first time. 相似文献
74.
The growing of large single crystals of stearic acid (CH3(CH2)16COOH), one of the saturated fatty acids, from organic solutions is reported. There are two parts in this experimental investigation; (1) to clarify the relationship between polymorphism of stearic acid having three modifications, namely, the A-form (orthorhombic), the B- and C-forms (monoclinic) and the growth conditions in the case of solution growth, because this complicated relationship has apparently made it very difficult to obtain large single crystals, (2) to produce large single crystals of stearic acid under the optimum growth conditions according to part (1). As a result large single crystals of stearic acid more than 8 × 8 mm2 in area of the B- and C-modifications were successfully obtained. The values of long spacing, the crystal habit and the cleavage plane are also reported. 相似文献
75.
A sulfur redox cycle between La(2)O(2)SO(4)(S(6+)) and La(2)O(2)S(S(2-)) phases was found for the first time to achieve the oxygen storage of 2 mol O(2) mol(-1), which is eight times larger than that of the conventional CeO(2)-ZrO(2) system. 相似文献
76.
We study the coexistence of symmetric non-Birkhoff periodic orbits of C(1) reversible monotone twist mappings on the cylinder. We prove the equivalence of the existence of non-Birkhoff periodic orbits and that of transverse homoclinic intersections of stable and unstable manifolds of the fixed point. We derive the positional relation of symmetric Birkhoff and non-Birkhoff periodic orbits and obtain the dynamical ordering of symmetric non-Birkhoff periodic orbits. An extension of the Sharkovskii ordering to two-dimensional mappings has been carried out. In the proof of various properties of the mappings, reversibility plays an essential role. (c) 2002 American Institute of Physics. 相似文献
77.
Ikushima Y Hatakeda K Sato M Sato O Arai M 《Chemical communications (Cambridge, England)》2002,(19):2208-2209
Our microreaction system using supercritical water solutions achieves nearly 100% yield and 100% selectivity for epsilon-caprolactam production at reaction times shorter than 1 s. 相似文献
78.
79.
80.
We study the radiative decays of the X(3872) in the charmonium-molecule model combined with the quark potential model. We obtain \({\Gamma(X(3872) \to J/\psi \, \gamma) = 29.2\,{\rm keV}}\) and \({\Gamma(X(3872) \to \psi' \, \gamma) = 6.3\,{\rm keV}}\) . The ratio of these two is 0.22, which is much smaller than the BABAR observation. We find that the result is very sensitive to the amount of the \({\chi_{c1}(1P)}\) component in the X(3872). 相似文献