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991.
Tomohiko Tagawa Yasuhito Fushii Hisao Imai Masahiro Yoshimura Shigeyuki Somiya 《Reaction Kinetics and Catalysis Letters》1989,39(1):49-53
Catalytic properties of a series of HfO2–Eu2O3 fine crystalline powders were examined by the isomerization of n-butenes. HfO2 pretreated at 873 K showed a high activity. It decreased with the addition of the Eu component. The product distributions are discussed on the basis of the acid-base properties.
HfO2–Eu2O3 -. HfO2, 873 K, . Eu. - .相似文献
992.
Ukai M Ajimura S Akikawa H Alburger DE Banu A Chrien RE Franklin GB Franz J Hashimoto O Hayakawa T Hotchi H Imai K Kishimoto T May M Millener DJ Minami S Miura Y Miyoshi T Mizunuma K Nagae T Nakamura SN Nakazawa K Okayasu Y Pile P Quinn BP Rusek A Sato Y Sutter R Takahashi H Tang L Tamura H Tanida K Yuan L Zhou SH;E 《Physical review letters》2004,93(23):232501
We have observed two gamma-ray transitions in (16)(Lambda)O from the 6.6 MeV excited 1(-)(2) state to both ground-state spin-doublet members (1(-)(1),0(-)) by the (K-,pi(-)gamma) reaction. We have obtained the ground-state doublet spacing to be 26.4+/-1.6(stat)+/-0.5(syst) keV and the excitation energy of the 1(-)(2) state to be 6561.7+/-1.1(stat)+/-1.7(syst) keV. The ground-state doublet spacing provides a small but nonzero strength of the tensor interaction between a Lambda and a nucleon. This is the first experimental result on the LambdaN tensor interaction. 相似文献
993.
Shimakoshi H Tokunaga M Kuroiwa K Kimizuka N Hisaeda Y 《Chemical communications (Cambridge, England)》2004,(1):50-51
Hydrophobic vitamin B(12) was covalently immobilized onto a platinum electrode surface, and the immobilized complex exhibits Co(ii)/Co(i) redox couple and in situ the Co(i) species reacts with phenethyl bromide to form styrene under irradiation with visible light with a turnover number of over 6000 for 1 h. 相似文献
994.
995.
Synthesis of [60]fullerene adducts bearing carbazole moieties by Bingel reaction and their properties 总被引:1,自引:0,他引:1
Carbazole-linked [60]fullerene adducts were successfully prepared by the Bingel reactions using carbazole derivatives bearing one or two ethyl malonate moieties. In the latter cases, specific bisadduct regioisomers were obtained, depending on the spacer unit between two ethyl malonate moieties. [reaction: see text] 相似文献
996.
Theoretical and experimental interpretations are given to the fact that in the optical Fresnel diffraction region acoustically modified spatial coherence is independent of the distance from the acoustic cell, but takes an identical expression across any planes parallel to the propagation direction of the acoustic wave. 相似文献
997.
The iron(III) complex of 2,7,12,17-tetraethyl-3,6,11,18-tetra-methylcorrphycene, an isomeric heme, was complexed with apomyoglobin to examine the ligand binding ability of the novel macrocycle under physiological conditions. The reconstituted holoprotein was found to be functionally active at pH 7.4 and 20 degrees C and to bind oxygen and carbon monoxide reversibly with a half-saturation pressure at 6.7 and 3.5mmHg, respectively. Equilibrium affinities for these ligands are one to two orders of magnitude lower than those reported for native myoglobin. The functional anomaly was ascribed to the geometric and electronic strain on the iron(II) atom in the trapezoidal coordination core of corrphycene. 相似文献
998.
Supercontinuum (SC) spectrum generation in a biconical tapered fiber is theoretically studied by taking into account the varying dispersion characteristics. Our numerical model is based on the extended nonlinear Schrödinger equation including higher-order dispersive terms, self-steepening, and Raman nonlinearity terms. We demonstrate how the group velocity dispersion and effective core area vary in the input taper region, which is significant for the broadening of the SC spectrum in the subsequent waist region. The evolutions of the unwrapped spectral phase and the spectral intensity along the transition and waist regions of the tapered fiber are also investigated in detail. It is found that the output taper has a considerable effect on the nonlinear variation of the spectral phase, e.g., 6.5 rad/THz in the infrared range of 280–300 THz (i.e., 1071–1000 nm in wavelength) and 21 rad/THz in the visible range of 600–620 THz (i.e., 500–484 nm). 相似文献
999.
Z. Elekes Zs. Dombrádi A. Saito N. Aoi H. Baba K. Demichi Zs. Fülöp J. Gibelin T. Gomi H. Hasegawa N. Imai M. Ishihara H. Iwasaki S. Kanno S. Kawai T. Kishida T. Kubo K. Kurita Y. Matsuyama S. Michimasa T. Minemura T. Motobayashi M. Notani T. K. Ohnishi H. J. Ong S. Ota A. Ozawa H. K. Sakai H. Sakurai S. Shimoura E. Takeshita S. Takeuchi M. Tamaki Y. Togano K. Yamada Y. Yanagisawa K. Yoneda 《The European physical journal. Special topics》2007,150(1):99-102
This paper reports on the 1H(28Ne,28Ne) and 1H(28Ne,27Ne)
reactions studied at intermediate energy using a liquid hydrogen target. From
the cross section populating the first 2+ excited state of 28Ne, and using the previously
determined B(E2) value, the neutron quadrupole transition matrix element has been
calculated to be Mn=13.8 ±3.7 fm2.
In the neutron knock-out reaction, two low-lying excited states were populated in 27Ne.
Only one of them can be interpreted by the sd shell model while the additional state
may intrude from the fp shell. These experimental observations
are consistent with the presence of fp shell configurations at low excitation energy
in 27,28Ne nuclei caused by a vanishing N=20 shell gap at Z=10. 相似文献
1000.
R Marumoto Y Yoshioka O Miyashita S Shima K Imai 《Chemical & pharmaceutical bulletin》1975,23(4):759-774