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61.
62.
Masahiro Isaka Hiroaki Homma Masaaki Kimura Akinobu Dote Akira Ohnishi 《Few-Body Systems》2013,54(7-10):1219-1222
The low-lying level structure of ${^{10}_\Lambda{\rm Be}}$ and ${^{12}_\Lambda{\rm Be}}$ has been studied by using the antisymmetrized molecular dynamics for hypernuclei (HyperAMD). In these hypernuclei, it is interesting to reveal the changes of excitation spectra by adding Λ hyperon, because the ground and low-lying states with different deformation coexist in 9Be and 11Be. Based on the HyperAMD calculation, it is found that the first excited state 1/2+ of 9Be is shifted up by about 700 keV in ${^{10}_\Lambda{\rm Be}}$ . In ${^{12}_\Lambda{\rm Be}}$ , the parity-inverted ground state of 11Be is reverted by adding Λ hyperon. In this article, we discuss the reason for these structure changes related to the coexistence of ground and low-lying states with different deformation. 相似文献
63.
64.
Akinobu Shiga 《Research on Chemical Intermediates》2002,28(5):485-492
Olefin insertion and chain transfer to monomer on [Oh-CH3MCl4]m(M = Ti, Zr, m = –1, –2: models of Ziegler-Natta catalysts) and [Td-CH3ML2]m(M = Ti, Zr; L = Cl, Cp m = 0, +1: models of metallocene catalysts) were analyzed by paired interacting orbitals (PIO) proposed by Fujimoto et al. Polymerization activities, molecular weights and regioselectivities of propylene insertion were easily predicted by using the total overlap population of all PIOs as an index of catalytic reactions. 相似文献
65.
66.
Dohi T Morimoto K Kiyono Y Maruyama A Tohma H Kita Y 《Chemical communications (Cambridge, England)》2005,(23):2930-2932
The head-to-tail (H-T) dimers could be obtained selectively by the oxidative coupling reaction of 3-substituted thiophenes using a combination of hypervalent iodine(III) reagents and trimethylsilyl trifluoromethanesulfonate. 相似文献
67.
K. Shoda H. Miyase M. Sugawara T. Saito S. Oikawa A. Suzuki J. Uegaki 《Nuclear Physics A》1975,239(3):397-411
The differential (e, e'p) cross sections of 88Sr, 89Y, 90Zr and 92Mo have been measured at θ = 90°. The results are used to obtain the (γ, p) cross sections by correcting with the angular distribution data. The (γ, p) cross sections are compared with the (γ, n) cross sections. A resonance corresponding to the T< GDR is found and another resonance is separated by fitting a Lorentz line with a width equal to that of the (γ, n) GDR. The ratios σ(γ, p)/σ(γ, n) and σ(γ, p0)/σ(γ, p) show differences between the two resonances. The two GDR resonances are studied from the isospin splitting point of view. The sum rule and splitting energy of the (γ, p) GDR agree well with theory. However, when the sum of the (γ, p) and (γ, n) experimental data is taken, the results are too large to be explained by the T> GDR. 相似文献
68.
Moser DF Naka A Guzei IA Müller T West R 《Journal of the American Chemical Society》2005,127(42):14730-14738
Reactions of stable silylenes 1 and 2 with a variety of halogenated organic compounds have been studied. Depending on the nature of the halocarbon, the products can be disilanes, LSiX-LSiR, or monosilanes, LSiXR, or a mixture of both types of products. Hexachloroethane reacts with the silylenes to give mainly the dichlorodisilane, LSiX-LSiX. The experimental results are rationalized in terms of several related free-radical chain mechanisms. 相似文献
69.
Cyclodextrin-modified micellar electrokinetic chromatography was applied to the enantioseparation of catechin and epicatechin using 6-O-alpha-D-glucosyl-beta-cyclodextrin together with sodium dodecyl sulfate and borate-phosphate buffer. Factors affecting chiral resolution and migration time of catechin and epicatechin were studied. The optimum running conditions were found to be 200 mM borate-20 mM phosphate buffer (pH 6.4) containing 25 mM 6-O-alpha-D-glucosyl-beta-cyclodextrin and 240 mM sodium dodecyl sulfate with an effective voltage of +25 kV at 20 degrees C using direct detection at 210 nm. Under these conditions, the resolution (Rs) of racemic catechin and epicatechin were 4.15 and 1.92, respectively. With this system, catechin and epicatechin enantiomers along with other four catechins ((-)-catechin gallate, (-)-epicatechin gallate, (-)-epigallocatechin, (-)-epigallocatechin gallate) and caffeine in tea samples were analyzed successfully. The difference of migration time between catechin and epicatechin is discussed. 相似文献
70.
Yamamoto A Yasuhara A Kodama S Matsunaga A Suzuki S Mohri S Yamada M 《Journal of separation science》2004,27(4):325-329
An ion-exclusion chromatographic method with on-line desalinization for the determination of volatile fatty acids in landfill leachates is described. Highly sensitive conductivity detection of the organic acids was achieved by using dilute p-hydroxybenzoic acid solution as an eluent. Interference with mineral acids was reduced by treatment with barium chloride solution prior to desalinization. A silver-loaded cation-exchange guard column for the desalinization was installed in series with the analytical column to avoid the contamination of organic acids. This method features detection limits of 0.01 mg L(-1) formic acid, 0.02 mg L(-1) acetic acid, 0.05 mg L(-1) propionic acid, and 0.1 mg L(-1) butyric acid, respectively, with an injection of 20 microL sample. Application of the on-line desalinization LC method is illustrated for leachate samples from a Japanese sanitary landfill. 相似文献