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排序方式: 共有295条查询结果,搜索用时 15 毫秒
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Dr. Takeshi Fujita Yutaro Kobayashi Dr. Ikko Takahashi Ryutaro Morioka Dr. Tomohiro Ichitsuka Prof. Dr. Junji Ichikawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(2):e202103643
Nickel-catalyzed reductive cross-coupling of allylic difluorides with aryl iodides was achieved via allylic C−F bond activation. Based on this protocol, a series of γ-arylated monofluoroalkenes were synthesized in moderate to high yields with high Z-selectivities. Mechanistic studies suggest that the C−I bonds of the aryl iodides and the C−F bonds of the allylic difluorides were cleaved via oxidative addition and β-fluorine elimination, respectively, where the oxidative addition of less reactive C−F bonds was avoided to permit their transformation. 相似文献
85.
Masataka Nakagawa Yui Tomioka Chiaki Sakuma Yasunori Kurosawa Takashi Shibata Tsutomu Arakawa Teruo Akuta 《Electrophoresis》2023,44(17-18):1446-1460
A new protocol for conducting two-dimensional (2D) electrophoresis was developed by combining the recently developed agarose native gel electrophoresis with either vertical sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis (PAGE) or flat SDS agarose gel electrophoresis. Our innovative technique utilizes His/MES buffer (pH 6.1) during the first-dimensional (1D) agarose native gel electrophoresis, which allows for the simultaneous and clear visualization of basic and acidic proteins in their native states or complex structures. Our agarose gel electrophoresis is a true native electrophoresis, unlike blue native–PAGE, which relies on the intrinsic charged states of the proteins and their complexes without the need for dye binding. In the 2D, the gel strip from the 1D agarose gel electrophoresis is soaked in SDS and placed on top of the vertical SDS–PAGE gels or the edge of the flat SDS–MetaPhor high-resolution agarose gels. This allows for customized operation using a single electrophoresis device at a low cost. This technique has been successfully applied to analyze various proteins, including five model proteins (BSA, factor Xa, ovotransferrin, IgG, and lysozyme), monoclonal antibodies with slightly different isoelectric points, polyclonal antibodies, and antigen–antibody complexes, as well as complex proteins such as IgM pentamer and β-galactosidase tetramer. Our protocol can be completed within a day, taking approximately 5–6 h, and can be expanded further into Western blot analysis, mass spectrometry analysis, and other analytical methods. 相似文献
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87.
Laurallene (), a new brominated cyclic ether having a terminal allene moiety, has been isolated as a main constituent from the marine red alga Yamada (Rhodomelaceae, Rhodophyta) and its structure was determined by its physical and chemical properties. 相似文献
88.
Tetsuro Murahashi Naohiro Kato Sensuke Ogoshi Hideo Kurosawa 《Journal of organometallic chemistry》2008,693(5):894-898
The reaction of a substitutionally labile dipalladium(I) complex [Pd2(CH3CN)6][BF4]2 (1) with 1,3,5,7-cyclooctatetraene (COT) in acetonitrile afforded [Pd2(μ-η3:η3-C8H8)(CH3CN)4][BF4]2 (2). The reaction of 2 with COT in acetonitrile yielded [Pd2(μ-η3:η3-C16H16)(CH3CN)4][BF4]2 (4), where COT is dimerized via C-C bond formation. Complexes 2 and 4 were structurally characterized by X-ray diffraction analyses. In dichloromethane, COT isomerized to styrene at room temperature in the presence of catalytic amount of 1, 2, or 4. 相似文献
89.
Real-time distance measurement of a moving object with high accuracy and high resolution using an ultrasonic wave is difficult due to the influence of the Doppler effect or the limit of the calculation cost of signal processing. An over-sampling signal processing method using a pair of LPM signals has been proposed for ultrasonic distance and velocity measurement of moving objects with high accuracy and high resolution. The proposed method consists of cross correlation by single-bit signal processing, high-resolution Doppler velocity estimation with wide measurement range and low-calculation-cost Doppler-shift compensation. The over-sampling cross-correlation function is obtained from cross correlation by single-bit signal processing with low calculation cost. The Doppler velocity and distance of the object are determined from the peak interval and peak form in the cross-correlation function by the proposed method of Doppler velocity estimation and Doppler-shift compensation. In this paper, the proposed method of Doppler-shift compensation is improved. Accuracy of the determined distance was improved from approximately within ±140 μm in the previous method to approximately within ±10 μm in computer simulations. Then, the proposed method of Doppler velocity estimation is evaluated. In computer simulations, accuracy of the determined Doppler velocity and distance were demonstrated within ±8.471 mm/s and ±13.87 μm. In experiments, Doppler velocities of the motorized stage could be determined within ±27.9 mm/s. 相似文献
90.
Let {R
n
}
n≥0 be a binary linear recurrence defined by R
n+2 = A
R
n+1 + B
R
n
(n ≥ 0), where A, B, R
0, R
1 are integers and Δ = A
2 + 4B > 0. We give necessary and sufficient conditions for the transcendence of the numbers
?k 3 0¢\fracakRrk+b,\sum_{k\geq 0}{}^{\prime}\frac{a_k}{R_{r^k}+b}, 相似文献 |