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991.
K. Shigemori D. Ichinose T. Irifune K. Otani T. Shiota T. Sakaiya H. Azechi 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,44(2):301-305
We present a novel scheme to measure sound velocity of
shock-compressed iron of geophysical interest. The sound velocity of
laser-irradiated iron foils was obtained with side-on X-ray radiograph
technique from measured rarefaction wave velocity of shocked iron. Iron
foils were irradiated with a two-stepped square laser pulse to reach Earth's
core condition by double compression. The experimental parameters of
temperature and pressure were very close to the Earth's core condition. 相似文献
992.
Takahiro Sugimoto Yuichi Tateishi Yoshihisa Sei Seiji Shinkai 《Tetrahedron letters》2005,46(32):5347-5350
A new strategy to control the orientation and aggregation numbers of porphyrins by alignment along well-defined templates has been demonstrated. Porphyrin-bridged bisPYBOX ligands were arranged along the oligomeric secondary dialkylammonium cations as templates to form well-defined supramolecular complexes. The templates controlled the aggregations of the porphyrins. 相似文献
993.
Kiyoshi Endo Takahiro Kitagawa Kenji Nakatani 《Journal of polymer science. Part A, Polymer chemistry》2006,44(13):4088-4094
The effect of an alkyl substituted in the aromatic ring of the salen ligand on the polymerization of butadiene (Bd) with (salen)Co(II) complexes in combination with methylaluminoxane (MAO) was investigated. The activity for the polymerization of Bd was influenced significantly by the introduction of alkyl groups at the 3,3′,5,5′‐positions in the aromatic ring of the salen ligand, and both the polymerization rate and 1,4‐cis contents increased in the following order with respect to the alkyl group: H < CH3 < t‐C4H9. This is in good agreement with the bulkiness of the alkyl groups. The activity for the polymerization of the (salen)Co(II) complex possessing t‐C4H9 at the 3,3′‐positions was higher than that of the (salen)Co(II) bearing t‐C4H9 at the 5,5′‐positions. Thus, the introduction of bulky substituents at the 3,3′‐positions of the salen ligand was an important factor in achieving both high activity and high 1,4‐cis selectivity in the polymerization of Bd with (salen)Co(II) complexes in combination with MAO. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4088–4094, 2006 相似文献
994.
Using an in situ pulsed laser photolysis/pulsed laser‐induced fluorescence/technique, the OH reaction kinetics of a three‐ring polycyclic aromatic hydrocarbon (PAH), phenanthrene (and its deuterated form), was investigated over the temperature range of 373–1000 K. This study represents the first examination of the OH kinetics for phenanthrene at elevated temperatures using the absolute rate technique. The phenanthrene results indicate a temperature dependence similar to its isomer anthracene, reported previously in R. Ananthula, T. Yamada, and P. H. Taylor, J Phys Chem A 2006, 100, 3559–3566, over a similar temperature range. The phenanthrene rate constants are similar to anthracene at high temperature (ca. 1000 K) and a factor of ca. 2 lower at low temperatures (373–700 K). The rate measurements were best fitted by the following two‐parameter expression of the form ATn: k1(373–1000 K) = 4.98 ± 2.96 × 10?6 * T?1.97±0.10 (in units of cm3 molecule?1 s?1, error limits ±1σ). Rate measurements with deuterated phenanthrene below 725 K were indistinguishable from the phenanthrene rate measurements, within random error limits, providing strong evidence for an OH‐addition mechanism. The effects of PAH size on their reactivity with OH radicals based on selected data over the temperature range of 243–1200 K are discussed. © 2007 Wiley Periodicals, Inc. Int J Chem Kinet 39: 629–637, 2007 相似文献
995.
A new integral transform whose kernel is a Stokes stream function of an exact solution to the axisymmetric stationary Euler
equations is derived with its inverse by using a Coulomb wave function. In the process of its derivation, a set of integral
transforms with respect to the radial variable is also found. Each of them is different from the Hankel (the Fourier–Bessel)
transform. 相似文献
996.
997.
Yuichi Ito Takahiro Shimada Jaekook Ha Martin Vacha Hisaya Sato 《Journal of polymer science. Part A, Polymer chemistry》2006,44(14):4338-4345
We report the preparation of a new electroluminescent polymer by the oxidative coupling copolymerization of N‐(4‐n‐butylphenyl)phenoxazine and 9,9‐di‐n‐butylfluorene with ferric(III) chloride. The reaction yields soluble polymers with a weight‐average molecular weight as high as 9000. The reactivity has been studied with respect to the reaction time, temperature, and feed ratio of the comonomers. Under optimum conditions, a copolymer with a 50% comonomer incorporation ratio can be obtained in a 75% yield. The polymers have been characterized with differential scanning calorimetry, cyclic voltammetry, and optical spectroscopy. A simple single‐layer light‐emitting‐diode device of an indium tin oxide/polymer/Mg–Ag structure shows a luminance of 200 cd/m2 at an 18‐V operating voltage. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4338–4345, 2006 相似文献
998.
Takahiro Hayashi 《Communications in Mathematical Physics》1993,157(2):331-345
For each Boltzmann weight of a face model, we associate two quantum groups (face algebras) which describe the dependence of the partition function on boundary value condition. Using these, we give a proof of (non-)flatness of A-D-E connections of A. Ocneanu, which is a crucial algebraic part of the classification of subfactors with Jones' index less than 4. 相似文献
999.
Naonobu Katada Takuya Toyama Miki Niwa Takahiro Tsubouchi Yuichi Murakami 《Research on Chemical Intermediates》1995,21(2):137-149
Structures of materials deposited from various Si alkoxides on alumina were determined based on gravimetry, product analysis
and coverage measurement. The activity for double-bond isomerization of l-butene was observed over the silica monolayer with a network of siloxanes (Si-O-Si) deposited from Si(OCH3)4 at 493 and 593 K. However, the isolated silica species deposited from Si(OCH3)4 at low temperatures (≤ 423 K) and those deposited from Si(OCH3)n(CH3)4-n (n ≥ 3) showed almost no activity. Based on these findings, the species — Al-O-SiOH in the network of Si-O-Si was suggested
to be the Bronsted acid site. 相似文献
1000.
Crystals of lead sulfate were precipitated in a solution of polyethylenimine (PEI) using a double-jet crystallizer. PEI controlled both the nucleation rate and the growth rate, and enabled to produce fine monodispersed crystals. This effect is considered to be due to a complexation between PEI and lead ion. The on-line measurement of the variation in the lead ion concentration indicated PEI lost its effect when a certain amount of reactants was supplied. And the duration in which PEI could control the precipitation rate and the amount of PEI had a strong correlation. In addition, it was suggested that their relationship could be utilized in order to produce monodispersed particles. 相似文献