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1.
Yoshinori Takanohashi Narumi Tabata Tomoaki Tanase Sadatoshi Akabori 《Journal of organometallic chemistry》1993,450(1-2):103-108
The reaction of bis(2-bromoethyl)selenium dibromide (1a) with 1,5-hexadiene (2) in methanol or ethanol affords 2,5-bis(alkoxymethyl)tetrahydroselenophene-1,1-dibromides (R = CH3 (3b), R = C2H5 (3c)) via 2,5-bis(bromomethyl)tetrahydroselenophene-1,1-dibromide (3a). The reaction of 1a with 2 in 1-propanol, 2-methyl-1-propanol or 1-butanol in the presence of sodium carbonate gave 2,5-bis(alkoxymethyl)tetrahydroselenophene (R = C3H7 (4a), R = (CH3)2CHCH2 (4b) and R = C4H9 (4c)) via 3a. The ratios of the trans and cis isomers of 3a–3c are 3:2. In addition, the structure of trans-2,5-bis(methoxymethyl)tetrahydroselenophene-1,1-dibromide (trans-3b) was determined by X-ray crystallography. 相似文献
2.
T. Yoshii H. Hara A. Kawamori K. Akabori M. Iwaki S. Itoh 《Applied magnetic resonance》1999,16(4):565-580
Light-induced spin-polarized radical pairs, P700+A1 ? in spinach photosystem (PS) I particles and P680+QA ? in Zn-substituted PS II core complexes, in oriented membranes were studied by pulsed electron paramagnetic resonance (EPR). Based on the determined distance of 25.2 ± 0.2 Å between P700 and A1, the angular dependence of the spin-polarized electron spin echo envelope modulation (ESEEM) spectra on the magnetic field suggests that the angle between $R_{P700 - {\rm A}_1 } $ , the radius-vector connecting P700 and A1, and the membrane normaln was 24 ± 4° in PS I particles. Obtained angle and distance of P700-A1 axis suggested QK side in the molecular geometry of cofactors presented in a recent X-ray crystallography of cyanobacterial PS I reaction center to be an active branch of electron transfer. The distance between P680 and QA was determined to be 27.4 ± 0.3 Å for a nonoriented PS II. The angle between $R_{P680 - Q_{\rm A} } $ , the radius-vector connecting P680 and QA, andn was determined to be 21 ± 5°. The angle of P680-QA axis was close to that of 20° of P870-QA axis reported in X-ray analysis of the purple bacterial reaction center crystal. 相似文献
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Toshiyuki Fujii Genki Okude Akihiro Uehara Shun Sekimoto Hirokazu Hayashi Mitsuo Akabori Kazuo Minato Hajimu Yamana 《Journal of Radioanalytical and Nuclear Chemistry》2011,288(1):181-187
Distribution behavior of Ce(III), Am(III), and Cm(III) between tri-n-butyl phosphate solution and molten calcium nitrate hydrate Ca(NO3)2·RH2O or molten calcium chloride hydrate CaCl2·RH2O was studied radiochemically. In Ca(NO3)2·RH2O systems, maximum separation factors of Ce and Cm to Am were observed to be 12 (Ce/Am) and 1.7 (Cm/Am). The distribution
ratios of these elements increased with the decrease of water activity in the hydrates, and the extractabilities at the water
deficient region was less sensitive compared to those at the water abundant region. This trend was similar to the coordination
circumstance change observed in electronic absorption spectra of Nd(III) in the hydrates. 相似文献
5.
A series of double armed diaza‐15‐crown‐5 ethers (9a ‐ 16a) and diaza‐18‐crown‐6 ethers (9b ‐ 16b) have been prepared by the Mannich reaction of 2,6‐disubstituted phenols with the corresponding N,N'‐dimethoxymethyldiaza‐crown ethers in benzene. The crystal structures of the diaza‐18‐crown‐6 ethers having iso‐propyl (10b) , tert‐butyl (11b) , and mixed methyl and tert‐butyl groups (12b) at positions 3′ and 5′ of the phenolic side arms were determined using X‐ray diffraction methods. Competitive transport by these ligands for sodium, potassium and cesium cations were measured under basic‐source phase and acidic‐receiving phase conditions. 相似文献
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Syoji Yamada Takashi Ohnishi Masashi Akabori Hiroshi Sugiura Eiichi Yamaguchi 《Solid State Communications》2005,133(10):647-649
Basic electronic properties of two-dimensional electron gas (2DEG) formed at GaN/AlGaN hetero-interface in large-scale (100 mm) wafer made by metal organic chemical vapour deposition (MOCVD) have been reported and discussed. From conventional Hall measurements, highest electron mobility was found to be μe∼1680 and 9000 cm2/V s at room temperature and at ∼5 K, respectively, for sheet electron density of ns∼8×1012 cm−2. In magneto-resistance (MR) measurements carried out at 1.5 K in Hall bar sample defined by photolithography and ion implantation, very clear Schubnikov de-Haas oscillations and integer quantum Hall effect were observed in diagonal (Rxx) and off-diagonal (Rxy) resistances, respectively. In addition, a good insulating nature of GaN layer is confirmed by capacitance-voltage (C-V) measurement. These results suggest the high-qualitiness of our 100 mm GaN/AlGaN high electron mobility transistor (HEMT) wafers comparable to those so far reported. 相似文献
8.
Sadatoshi Akabori Hiroyuki Munegumi Seiichi Sato Masaru Sato 《Journal of organometallic chemistry》1984,272(3):C54-C56
Thiacrown ethers containing ruthenocene as a subunit were synthesized by the reaction of 1,1′-bis(3-chloropropyl-1-thia)ruthenocene with disodium dithiolates in THF/EtOH. In these reactions, some unexpected products were obtained. 相似文献
9.
Abstract The Syn isomers (3b and 4b) of xylene-bridged cryptophane showed selective complexing abilities for 2,2-dimethylbutane, 3-methylpentane, 3,3-di-methylpentane and 3-ethylpentane among the investigated alkanes, although the Anti isomers (3a,4a,5a) did not complex with these alkanes. However, both the Anti-and Syn-isomers (2a and 2b) of the diethyleneoxy-bridged cryptophane showed selective complexing abilities for 2,2-dimethylbutane, 3,3-dimethylpentane, 2,2,3-trimethylbutane and 2,2,3,3-terramethybutane among the investigated alkanes. 相似文献
10.
2-Selena-1,3-dicalcogena[3]metallocenophanes are obtained in high and moderate yields by the reaction of metallocene-1,1′-dithiol and -diselenol with bis(2-bromoethyl)selenium dibromide under mild conditions. 相似文献