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991.
张玉虎 M.Oshima T.Morikawa T.Hayakawa Y.Toh 周小红 何建军 刘忠 甘再国 T.Shizuma M.Koizumi A.Osa J.Katakura Y.Hatsukawa M.Matsuda< sup 《中国物理 C》2003,27(4):313-318
利用重离子熔合蒸发反应和在束γ谱学实验方法研究了双奇核176,178Ir和182Au的高自旋态结构,在这3个双奇核中观测到了基于πi13/2 νi13/2准粒子组态下的转动带.以能级间隔系统学为判据,对184Au核中πi13/2 νi13/2转动带能级自旋进行了指定.指出176,178Ir和182,184Au 4个双奇核的πi13/2 νi13/2转动带在低自旋区均出现旋称反转.对πi13/2 νi13/2转动带旋称反转现象进行了定性的讨论.用推转壳模型对πh9/2 νi13/2带和πi13/2 νi13/2带能级结构进行了理论研究,发现当采用形变和对力自洽计算后,从理论上可以定性地解释两个半退耦带出现的旋称反转现象. 相似文献
992.
C. B. Moon C. S. Lee S. J. Chae J. H. Ha J. C. Kim T. Komatsubara T. Hayakawa J. Lu M. Matsuda T. Watanabe K. Furuno 《Zeitschrift für Physik A Hadrons and Nuclei》1997,357(1):53-59
High-spin states of the 115Te were studied by in-beam spectroscopy with the 89Y (29Si, p2n) fusion-evaporation reaction at a beam energy of 108 MeV. γ?γ coincidence and γ?γ angular correlation analyses were employed for determining the level scheme of 115Te. We have identified two vibrational-like bands built on the νh11/2 and νg7/2 quasiparticle states and the noncollective oblate states from the full alignment of quasiparticle configurations. In addition, a regular ΔI = 2 sequence with positive-parity was found for the first time in odd-A Te nuclei. This sequence is interpreted as a deformed structure resulting from three-quasiparticle alignment having the [π(g7/2, h 11/2) ? ν(h 11/2)] configuration. Calculations of total Routhian surfaces and cranked shell model were performed and were used for assigning quasiparticle configurations to the states in 115Te. 相似文献
993.
Summary The optimal peak separation is defined as one from which the maximal amount of Shannon information called FUMI can be collected. The optimal peak separation depends on the peak-resolving powers of the data processing used for a chromatographic system. Data processings of different peak-resolving powers have their own optimal peak separation of different Rs. This paper demonstrates that a data processing of superior powers can collect more information from the optimal than an inferior one, although the information FUMI is calculated from their own optimals. The flow chart for the calculation of FUMI is annexed. 相似文献
994.
995.
Shigeki Matsuda 《Compositio Mathematica》2002,134(1):1-34
Let k be a field and X = Spec (k[t,t
-1
]). Katz proved that a differential equations with coefficients in k((t
-1
)) is uniquely extended to a special algebraic differential equation on X when k is of characteristic 0. He also proved that a finite extension of k((t
-1
)) is uniquely extended to a special covering of X when k is of any characteristic. These theorems are called canonical extension or Katz correspondence. We shall prove a p-adic analogue of canonical extension for quasi-unipotent overconvergent isocrystals. As a consequence, we can show that the local index of a quasi-unipotent overconvergent is equal to its Swan conductor. 相似文献
996.
Takaaki Horaguchi Shinichi Matsuda Kiyoshi Tanemura Tsuneo Suzuki 《Journal of heterocyclic chemistry》1987,24(4):965-969
3-Methyl-5-nitrobenzofuran ( 2 ) and 3-methyl-5-nitrobenzofuran-2-carboxylic acid ( 3 ) were obtained by heating 2-acetyl-4-nitrophenoxyacetic acid ( 1 ) with various bases in acetic anhydride. It appeared that 3-hydroxy-3-methyl-5-nitro-2,3-dihydrobenzofuran-2-carboxylic acid ( 4 ) was the intermediate in the benzofuran synthesis. The properties of 4 were examined under various conditions. Using strong bases such as triethyl-amine in place of sodium acetate, 3-methyl-5-nitrobenzofuran-2-carboxylic acid ( 3 ) was obtained exclusively. However, in the presence of acetic acid in the reaction mixture 3-methyl-5-nitrobenzofuran ( 2 ) was obtained in good yield. The reaction pathways for the formation of 2 and 3 are discussed. 相似文献
997.
The vacuum space inside carbon nanotubes offers interesting possibilities for the inclusion, transportation, and functionalization of foreign molecules. Using first-principles density functional calculations, we show that linear carbon-based chain molecules, namely, polyynes (C(m)H(2), m = 4, 6, 10) and the dehydrogenated forms C(10)H and C(10), as well as hexane (C(6)H(14)), can be spontaneously encapsulated in open-ended single-walled carbon nanotubes (SWNTs) with edges that have dangling bonds or that are terminated with hydrogen atoms, as if they were drawn into a vacuum cleaner. The energy gains when C(10)H(2), C(10)H, C(10), C(6)H(2), C(4)H(2), and C(6)H(14) are encapsulated inside a (10,0) zigzag-shaped SWNT are 1.48, 2.04, 2.18, 1.05, 0.55, and 1.48 eV, respectively. When these molecules come inside a much wider (10,10) armchair SWNT along the tube axis, they experience neither an energy gain nor an energy barrier. They experience an energy gain when they approach the tube walls inside. Three hexane molecules can be encapsulated parallel to each other (i.e., nested) inside a (10,10) SWNT, and their energy gain is 1.98 eV. Three hexane molecules can exhibit a rotary motion. One reason for the stability of carbon chain molecules inside SWNTs is the large area of weak wave function overlap. Another reason concerns molecular dependence, that is, the quadrupole-quadrupole interaction in the case of the polyynes and electron charge transfer from the SWNT in the case of the dehydrogenated forms. The very flat potential surface inside an SWNT suggests that friction is quite low, and the space inside SWNTs serves as an ideal environment for the molecular transport of carbon chain molecules. The present theoretical results are certainly consistent with recent experimental results. Moreover, the encapsulation of C(10) makes an SWNT a (purely carbon-made) p-type acceptor. Another interesting possibility associated with the present system is the direction-controlled transport of C(10)H inside an SWNT under an external field. Because C(10)H has an electric dipole moment, it is expected to move under a gradient electric field. Finally, we derive the entropies of linear chain molecules inside and outside an open-ended SWNT to discuss the stability of including linear chain molecules inside an SWNT at finite temperatures. 相似文献
998.
Matsuda T Yamaguchi Y Shigeno M Sato S Murakami M 《Chemical communications (Cambridge, England)》2011,47(30):8697-8699
In the presence of gold(I)-phosphine catalysts, alkenyl- and arylsilanes undergo intramolecular cyclisation reactions onto appendant alkyne moieties to afford 1-silaindene derivatives. The reaction pathways vary depending on the substituent on silicon. 相似文献
999.
Quantum chemical calculations were performed to analyze the excited states and the redox potentials of a recently synthesised fluorine-containing porphycene, 2,7,12,17-tetraethyl-3,6,13,16-tetrakis(trifluoromethyl) porphycene. The reduction and oxidation potentials of the porphycenes measured by cyclic voltammetry were semiquantitatively reproduced using density-functional theory (DFT) and polarizable continuum model calculations, in which solvent effect and basis-sets extension effect were indispensable. Symmetry-adapted cluster configuration interaction and time-dependent (TD) DFT calculations were performed to analyze the visible region of the absorption spectra, and the results were in good agreement with the experimental data. The results of the calculations showed that both structural distortion and electronic effects cause specifically large stabilization of the LUMO level and become the origin of the particularly large positive-side shift of the reduction potential and the red-shift in the Q band absorption. 相似文献
1000.
Maeda H Eifuku N Haketa Y Ito Y Lee E Lee M 《Physical chemistry chemical physics : PCCP》2011,13(9):3843-3850
Wedge-shaped amphiphilic derivatives of 1,3-dipyrrolyl-1,3-propanedione boron complexes, with one or no aliphatic chains attached at one aryl moiety and three hydrophilic chains at the other, exhibited formation of assembled structures in aqueous solutions. UV/vis, fluorescence and DLS analyses suggested that the wedge-shaped amphiphiles exist in assembled modes in the solution state, and TEM measurements revealed that a balance of hydrophobic and hydrophilic moieties in the amphiphiles is crucial for the formation of organized structures in aqueous solutions as evidenced by the formation of spherical and cylindrical micelles. 相似文献