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排序方式: 共有294条查询结果,搜索用时 15 毫秒
71.
In this paper, we obtain a sufficient condition for the convergence of positive linear operators in Banach function spaces on \({\mathbb {R}}^n\) and derive a Korovkin type theorem for these spaces. Also, we generalized this result via statistical sense. 相似文献
72.
We consider nonparametric Bayesian estimation of the drift coefficient of a multidimensional stochastic differential equation from discrete-time observations on the solution of this equation. Under suitable regularity conditions, we establish posterior consistency in this context. 相似文献
73.
Tomoki Saka Toru Okaki Shohei Ifuku Yukiko Yamashita Kasumi Sato Shota Miyawaki Akiko Kamori Atsushi Kato Isao Adachi Yasuhiro Tezuka Peter G. Kiria Osamu Onomura Daishiro Minato Kenji Sugimoto Yuji Matsuya Naoki Toyooka 《Tetrahedron》2013
Synthesis and inhibitory activities against α-l-fucosidase of phenylalkyl-substituted polyhydroxypiperidines have been described. Among the newly synthesized compounds, 2,4,6-trichloro derivative (16q) showed very high inhibitory activity against α-l-fucosidase with IC50 value of 0.005 μM, and Ki values of 0.0011 μM, respectively. 相似文献
74.
Dr. Toshifumi Dohi Nobutaka Yamaoka Shota Nakamura Kohei Sumida Koji Morimoto Prof. Dr. Yasuyuki Kita 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(6):2067-2075
We have successfully established an efficient route to the core structure of donor–acceptor head‐to‐tail (H–T)‐linked regioregular oligothiophenes, which includes the following key synthetic steps, that is, hypervalent iodine induced direct and regioselective coupling of thiophenes and the use of the obtained bithiophenes as excellent coupling substrates for the Suzuki and Stille couplings. The versatility of this new approach is highlighted in the dramatic improvement of the yield (ca. 59 % overall yield) of MK‐2, a high‐performance organic dye, for photovoltaic applications. 相似文献
75.
Morrey Spaces for Non-doubling Measures 总被引:6,自引:0,他引:6
Yoshihiro SAWANO Hitoshi TANAKA 《数学学报(英文版)》2005,21(6):1535-1544
The authors give a natural definition of Morrey spaces for Radon measures which may be non-doubling but satisfy certain growth condition, and investigate the boundedness in these spaces of some classical operators in harmonic analysis and their vector-valued extension. 相似文献
76.
Application of a Palladium‐Catalyzed C−H Functionalization/Indolization Method to Syntheses of cis‐Trikentrin A and Herbindole B
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Raul A. Leal Caroline Bischof Youjin V. Lee Shota Sawano Christopher C. McAtee Luke N. Latimer Zachary N. Russ Prof. John E. Dueber Prof. Jin‐Quan Yu Prof. Richmond Sarpong 《Angewandte Chemie (International ed. in English)》2016,55(39):11824-11828
We describe herein formal syntheses of the indole alkaloids cis‐trikentrin A and herbindole B from a common meso‐hydroquinone intermediate prepared by a ruthenium‐catalyzed [2+2+1+1] cycloaddition that has not been used previously in natural product synthesis. Key steps include a sterically demanding Buchwald–Hartwig amination as well as a unique C(sp3)?H amination/indole formation. Studies toward a selective desymmetrization of the meso‐hydroquinone are also reported. 相似文献
77.
Shota Nagasaki 《Tetrahedron letters》2008,49(22):3578-3581
[2+2] Cycloaddition reactions of P2 with alkenes were predicted to have concerted paths, that is, pseudoexcitation, distorted 2πs+2πs, and 2πs+2πa processes without any interventions of intermediates. The pseudoexcitation and/or distorted 2πs+2πs paths with retention of configuration of alkenes are kinetically preferred to the 2πs+2πa path with inversion of configuration. The reactions were predicted from the appreciable difference in the calculated enthalpies of activation to be stereospecific. 相似文献
78.
Takatsugu Endo Shota Suzuki Nobukazu Miyagawa Shigeru Takahara 《Journal of photochemistry and photobiology. A, Chemistry》2008,200(2-3):181-186
We present N-(p-anilinesulfonyloxy)-1,8-naphthalimide (ASNI) as fluorescence imaging material based on a novel fluorescence imaging mechanism. ASNI is composed of two functional moieties in one molecule: an acid-reactive fluorescence probe and a photoacid generator (PAG). When ASNI is photoirradiated, a bond in the PAG moiety breaks and an acid is generated. The fluorescence probe moiety then detects the acid and fluoresces. We call this novel mechanism a self-contained photoreaction (SCP). The photophysical properties and photoreactivity of ASNI were measured and compared with those of a prototype PAG, N-(phenylsulfonyloxy)-1,8-naphthalimide. These were well represented by density functional theory calculations. SCP permits one-step fluorescence imaging without any wet or dry developing process. 相似文献
79.
Malval JP Suzuki S Morlet-Savary F Allonas X Fouassier JP Takahara S Yamaoka T 《The journal of physical chemistry. A》2008,112(17):3879-3885
The photophysical properties of a series of 1,8-naphthalimide photoacid generators were studied by steady state fluorescence and phosphorescence spectroscopy. Emission and excitation anisotropies, triplet quantum yields in polar and nonpolar solvent and photoacid generation were evaluated. The singlet excited state exhibits a low polarity and is strongly deactivated by an efficient intersystem crossing process. In protic solvent, a homolytic singlet cleavage of the N-O bond occurs and leads to the acid production. The existence of a triplet state close to the singlet state was clearly evidenced. The presence of close singlet excited states is supported by fluorescence anisotropy and picosecond laser spectroscopy experiments. Results of DFT calculations well confirm the experimental contentions and yield important information about the cleavage process involved in such compounds. 相似文献
80.
Yosihiro Sawano Hiroshi Fujiwara Saburou Saitoh 《Complex Analysis and Operator Theory》2008,2(3):511-521
We investigate compactness of linear operators associated with the real inversion formulas of the Laplace transform, coming
with weighted Sobolev reproducing kernel Hilbert spaces on the half line R
+. We present concrete reproducing kernels along with several typical examples.
Submitted: October 13, 2007. Accepted: November 11, 2007. 相似文献