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211.
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Measurements of X-ray scattering intensity from a ferroelectric liquid crystal are carefully carried out to clarify the mechanism of the ferroelectric phase transition. The temperature dependences of the scattering intensity and the tilt angle of the molecules in the ferroelectric smectic C phase are discussed on the base of Landau's theory. 相似文献
213.
Development of an electrochemical detector for high-performance liquid chromatographic assay of brain catecholamines 总被引:1,自引:0,他引:1
An electrochemical detector that utilizes the reduction-oxidation phenomena of electrochemically active substances has been developed for high-performance liquid chromatography. The construction and application of the detector to brain catecholamines, particularly for norepinephrine and dopamine analysis, are described. The differences between this detector and those reported previously are discussed. 相似文献
214.
Kouichi Yamaguchi Takeshi Wada Shinsaku Maruyama Masaaki Takehisa 《Journal of Polymer Science.Polymer Physics》1973,11(8):1573-1584
The molecular weight distribution of polyethylene produced by radiation was calculated according to a kinetic scheme. The calculated molecular weight distribution was compared with the results deduced from gel-permeation chromatography. The observed distribution curve from GPC was broader and showed a lower degree of polymerization than the calculated one. Discrepancies between observed and calculated curves can be explained if the polymer contains nonsteady-state products and if the reaction mechanism includes chain transfer to dead polymer. By this reaction long-chain branching would occur. Several long-chain branches per polymer molecule were indeed found, as inferred from solution properties. 相似文献
215.
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217.
Iwaki O. K. Hikichi M. Kaneko S. Shimizu und T. Maruyama 《Colloid and polymer science》1975,253(4):340
Ohne Zusammenfassung 相似文献
218.
H. Yamazaki T. Yorita T. Kinoshita T. Okuda H. Matsui T. Maruyama J. Kasagi T. Suda K. Itoh T. Miyakawa H. Okuno H. Shimizu H. Y. Yoshida T. Kinashi 《Nuclear Physics A》2000,670(1-4):202-205
In order to study the S11(1535) resonance in the nuclear medium, total cross sections of the (γ, η) reactions on C, Al and Cu have been measured for photon energies between 680 and 1000 MeV. A broad resonance due to the excitation and decay of the S11 resonance in the nucleus has been clearly observed for the first time. The apparent energy and width of the resonance are 900 and 300 MeV, respectively. Model calculations based on the quantum molecular dynamics have been performed. A comparison of the calculations with the data indicates that the S11 resonance in nuclei should have a larger width; the width of about 250 MeV is required while the elementary one is about 150 MeV. 相似文献
219.
Optical,Electrochemical, and Magnetic Properties of Pyrrole‐ and Thiophene‐Bridged 5,15‐Diazaporphyrin Dimers 下载免费PDF全文
Satoshi Omomo Yasuhisa Maruyama Prof. Dr. Ko Furukawa Dr. Taniyuki Furuyama Prof. Dr. Haruyuki Nakano Prof. Dr. Nagao Kobayashi Prof. Dr. Yoshihiro Matano 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(5):2003-2010
The first examples of pyrrole‐ and thiophene‐bridged 5,15‐diazaporphyrin (DAP) dimers are prepared through Stille coupling reactions of nickel(II) and copper(II) complexes of 3‐bromo‐10,20‐dimesityl‐5,15‐diazaporphyrin (mesityl=2,4,6‐trimethylphenyl) with the respective 2,5‐bis(tributylstannyl)heteroles. The effects of the heterole spacers and meso nitrogen atoms on the optical, electrochemical, and magnetic properties of the DAP dimers are investigated by UV/Vis absorption spectroscopy, density functional theory calculations, magnetic circular dichroism spectroscopy, cyclic voltammetry, and EPR spectroscopy. The heterole spacers are found to have a significant impact on the electronic transitions over the entire π‐system. In particular, the pyrrole‐bridged DAP dimers exhibit high light‐harvesting potential in the low‐energy visible/near‐infrared region owing to the intrinsic charge‐transfer character of the lowest excitation. 相似文献
220.
Alexander G. O'Brien Akinobu Maruyama Yasuhide Inokuma Makoto Fujita Phil S. Baran Donna G. Blackmond 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(44):12062-12065
Electrochemical reactions are shown to be effective for the C H functionalization of a number of heterocyclic substrates that are recalcitrant to conventional peroxide radical initiation conditions. Monitoring reaction progress under electrochemical conditions provides mechanistic insight into the C H functionalization of a series of heterocycles of interest in medicinal chemistry. 相似文献