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1.
Various 2-substituted indoles were prepared by heteroannulation of o-iodoanilines and terminal alkynes in a one-pot reaction with a Pd(II)-NaY zeolite catalyst. The product formation largely depended on the solvent, base, and reaction temperature. The recycled catalyst showed good reusability in the heteroannulation reaction. 相似文献
2.
Dong‐Cheol Shin Yun‐Hi Kim Hong You Jae Gyu Jin Soon‐Ki Kwon 《Journal of polymer science. Part A, Polymer chemistry》2004,42(22):5636-5646
A poly(p‐phenylenevinylene) (PPV) derivative containing a bulky (2,2‐diphenylvinyl)phenyl group in the side chain, EHDVP‐PPV, was synthesized by Gilch route. The reduced tolane‐bisbenzyl (TBB) defects, as well as the structure of the polymer, was confirmed by various spectroscopic methods. The intramolecular energy transfer from the (2,2‐diphenylvinyl)phenyl side group to the PPV backbone was studied by UV‐vis and photoluminescence (PL) of the obtained polymer and model compound. The polymer film showed maximum absorption and emission peaks at 454 and 546 nm, respectively, and high PL efficiency of 57%. A yellow electroluminescence (λmax = 548 nm) was obtained with intensities of 6479 cd/m2 when the light‐emitting diodes of ITO/PEDOT/EHDVP‐PPV/LiF/Al were fabricated. The maximum power efficiency of the devices was 0.729 lm/W with a turn‐on voltage of 3.6 V. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5636–5646, 2004 相似文献
3.
An algorithm for a time accurate incompressible Navier–Stokes solver on an unstructured grid is presented. The algorithm uses a second order, three‐point, backward difference formula for the physical time marching. For each time step, a divergence free flow field is obtained based on an artificial compressibility method. An implicit method with a local time step is used to accelerate the convergence for the pseudotime iteration. To validate the code, an unsteady laminar flow over a circular cylinder at a Reynolds number of 200 is calculated. The results are compared with available experimental and numerical data and good agreements are achieved. Using the developed unsteady code, an interaction of a Karman vortex street with an elliptical leading edge is simulated. The incident Karman vortex street is generated by a circular cylinder located upstream. A clustering to the path of the vortices is achieved easily due to flexibility of an unstructured grid. Details of the interaction mechanism are analysed by investigating evolutions of vortices. Characteristics of the interactions are compared for large‐ and small‐scale vortex streets. Different patterns of the interaction are observed for those two vortex streets and the observation is in agreement with experiment. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
4.
Ki Sik Ha 《Semigroup Forum》1989,38(1):215-221
LetZ be a generator of an exponentially boundedC-semigroup {S
t
}
t≥0 in a Banach space and letT
t
=C
−1
S
t
. We show that the spectral mapping theorems such as exp(tσ(Z)) ⊂ σ(T
t
) and exp(tσ
p
(Z)) ⊂ tσ
p
(T
t
) ⊂ exp(tσ
p
(Z)) ⋃ {0} for everyt≥0 hold.
The present studies were supported by the Basic Science Research Institute Program, Ministry of Education, 1987. 相似文献
5.
Teruhiko Kai Yasunori Suma Shuichiro Ono Takeo Yamaguchi Shin‐ichi Nakao 《Journal of polymer science. Part A, Polymer chemistry》2006,44(2):846-856
We have investigated the effect of the surface state and surface treatment of the pores of an inorganic substrate on the plasma‐grafting behavior of pore‐filling‐type organic/inorganic composite membranes. Shirasu porous glass (SPG) was used as the inorganic substrate, and methyl acrylate was used as the grafting monomer. The grafting rate increased as the density of silanol on the SPG substrate increased. This result suggests that radicals are generated mainly at the silanol groups on the pore surface by plasma irradiation. The SPG substrates were treated with silane coupling agents used to control the mass of organic material bonded to the pore surface. The thickness of the grafted layer became thinner as the mass of organic material bonded to the pore surface of SPG increased. This decrease in the thickness of the grafted layer could be explained by the decrease in the penetration depth of vacuum ultraviolet rays contained in plasma having a wavelength of less than 160 nm that generated radicals in the pores of the substrate. The thickness of the grafted layer inside the SPG substrates could be controlled through the control of the mass of organic material bonded to the pore surface of the SPG substrate. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 846–856, 2006 相似文献
6.
Masahiro Nakao Chikako Yamazaki Hiroshi Tominaga Takako Yamaguchi Yoshikazu Fujita 《Analytical sciences》2006,22(2):313-316
A simple and highly sensitive spectrophotometric method for the determination of anthracycline anticancer agents, such as Daunorubicin hydrochloride (DAU), was established by using aluminum(III) and Chromazurol S (CAS) in a nonionic surfactant micellar medium. In the case of determination of DAU, the apparent molar absorptivity was 1.3 x 10(5) dm3 mol(-1) cm(-1) at 615 nm. Beer's law was obeyed in the concentration range of 0.028 - 2.82 microg ml(-1) for DAU. Owing to no need for solvent extraction, this method could be applied to assays of DAU and related drugs in pharmaceutical preparations. 相似文献
7.
T Nakao M Obata M Kawakami K Morita H Tanaka Y Morimoto S Takehara T Yakushiji T Tahara 《Chemical & pharmaceutical bulletin》1991,39(10):2556-2563
A series of 2-aryl-5,6-dihydro-(1)benzothiepino[5,4-c]pyridazin-3(2H)- ones and related compounds were synthesized and evaluated for their ability to displace 3H-diazepam from rat brain membranes in vitro, and to prevent bicuculline induced convulsions in mice in vivo. Compounds with a 4'-methoxyphenyl (36) or 4'-chlorophenyl group (37, 39--42) as 2-aryl substituents showed prominent activities in both the in vitro and in vivo tests. Among them, 2-(4'-chlorophenyl)-5,6-dihydro- (37) and 2-(4'-chlorophenyl)-5,6-dihydro-10-fluoro-(1)benzothiepino[5,4-c]+ ++pyridazin- 3(2H)-one 7-oxides (41) showed activity twice as potent as diazepam in an anticonflict test (Vogel type, rats) while exhibiting less muscle relaxation (rotarod test, mice) and augmentation of gamma-aminobutyric acid-induced chloride current (Icl) in isolated frog sensory neurones than diazepam. Compound 37 (Y-23684) was selected from this series as a candidate for further development. The structure-activity relationships are discussed. 相似文献
8.
9.
10.
We consider the time-dependent Schrödinger-Hartree equation (1) $$iu_t + \Delta u = \left( {\frac{1}{r}*|u|^2 } \right)u + \lambda \frac{u}{r},(t, x) \in \mathbb{R} \times \mathbb{R}^3 ,$$ (2) $$u(0,x) = \phi (x) \in \Sigma ^{2,2} ,x \in \mathbb{R}^3 ,$$ where λ≧0 and \(\Sigma ^{2,2} = \{ g \in L^2 ;\parallel g\parallel _{\Sigma ^{2,2} }^2 = \sum\limits_{|a| \leqq 2} {\parallel D^a g\parallel _2^2 + \sum\limits_{|\beta | \leqq 2} {\parallel x^\beta g\parallel _2^2< \infty } } \} \) . We show that there exists a unique global solutionu of (1) and (2) such that $$u \in C(\mathbb{R};H^{1,2} ) \cap L^\infty (\mathbb{R};H^{2,2} ) \cap L_{loc}^\infty (\mathbb{R};\Sigma ^{2,2} )$$ with $$u \in L^\infty (\mathbb{R};L^2 ).$$ Furthermore, we show thatu has the following estimates: $$\parallel u(t)\parallel _{2,2} \leqq C,a.c. t \in \mathbb{R},$$ and $$\parallel u(t)\parallel _\infty \leqq C(1 + |t|)^{ - 1/2} ,a.e. t \in \mathbb{R}.$$ 相似文献