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Takayuki Motoyama Toshiaki Hayashi Hiroshi Hirota Masashi Ueki Hiroyuki Osada 《Chemistry & biology》2012,19(12):1611-1619
Highlights? The terpendole biosynthetic gene cluster was isolated ? Terpendole E is a key biosynthetic intermediate of indole-diterpenes ? Terpendole E was overproduced by gene knockout of the bispecific enzyme TerP ? Indole-diterpene biosynthetic pathways can be classified into two groups 相似文献
34.
The laser-induced thermal acoustics (LITA) method was used to measure the temperature profiles induced behind spherical shock
waves, generated by high-voltage discharge in air with an energy of 6 J. A Nd:YAG laser (wavelength 532 nm, energy 300 mJ,
pulse duration 10 ns, line width 0.005 cm−1) and an Ar-ion laser (wavelength 488 nm, power 4 W) served as the pump and probe lasers, respectively for the LITA measurements.
The peak temperatures were in good agreement with results calculated with the Euler equations. The temperature profiles behind
the shock, however, differed in decay rates. The peak temperatures behind the shock wave were determined by reflected overpressure
and agreed with those from the LITA measurements within a maximum error of 5%. 相似文献
35.
Toyoki Kunitake 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(5):797-816
Polymerization with many triphenylmethyl salts was conducted for α-methylstyrene, isobutyl vinyl ether, t-butyl vinyl ether, and spiro[2,4]hepta-4,6-diene (SHD). The variation of polymer structure (the isotactic unit content for the first three monomer systems and the amount of the 1,4-addition structure for SHD) showed fairly simple correlations with the counteranion size. The results can be interpreted in terms of the tightness of the propagating ion pair within the framework of a theory of the cationic propagation which had been proposed. When the counteranion radius was greater than 3.5 Å, the counteranion exerts a parallel influence on the tightness of the growing ion pair without regard to the monomer structure. However, in the case of smaller counterions, the tightness appears to be determined by the relative sizes of counteranion and monomer. The penta-coordinated counteranions gave rise to the polymer structure which would arise from tighter ion pairs than expected from their sizes alone. The polymer structure was also affected by the initiator concentration in these cases. These results are attributed to peculiar characteristics of penta-coordinated anions. 相似文献
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Satoru Nakashima Tsuneo Koura Motomi Katada Hirotoshi Sano Izumi Motoyama 《Hyperfine Interactions》1990,53(1-4):361-366
TCNQ salts of 1-monoalkylbiferrocenes showed a temperature-independent trapped-valence state as expected for the unsymmetrical structure of cations. On the other hand, mixed crystals of 1-monobutyl- and 1.1-dibutylbiferrocenium+(TCNQ)
3
–
showed a temperature dependence of the mixed-valence states, showing that the lattice affects the mixed-valence states. 相似文献
39.
Chuji Aso Sanae Tagami Toyoki Kunitake 《Journal of polymer science. Part A, Polymer chemistry》1970,8(6):1323-1336
Copolymerizations of three phthalaldehyde isomers (M2) with styrene (M1) were carried out in methylene chloride or in toluene with BF3OEt2 catalyst. The monomer reactivity ratios were r1 = 0.77, r2 = 0 for the meta isomer and r1 = 0.60, r2 = 0 for the para isomer. The second aldehyde group of both isomers did not participate in polymerization and acted simply as the electron-withdrawing group, thus reducing the cationic reactivity of these monomers. Copolymerization behaviors of the ortho isomer (o-PhA) were quite different between 0°C and ?78°C. At ?78°C, o-PhA preferentially polymerized to yield “living” cyclopolymers, until an equilibrium concentration of o-PhA monomer was reached. Then, styrene propagated from the living terminal rather slowly. The block structure of the copolymer was confirmed by the chemical and spectroscopic means. In the copolymerization at 0°C, the o-PhA unit in copolymer consisted both of cyclized and uncyclized units. This copolymer seemed to contain short o-PhA sequences. The variation of the o-PhA-St copolymer structure with the polymerization temperature was explained on the basis of whether the polymerization was carried out above or below the ceiling temperature (?43°C) of the homopolymerization of o-PhA. 相似文献
40.
M. Katada S. Nakashima Y. Uchida I. Motoyama H. Sano H. Sakai Y. Maeda 《Journal of Radioanalytical and Nuclear Chemistry》1986,104(6):349-358
129I-Mössbauer spectroscopic data are presented for the titled iodides. Comparison of Mössbauer parameters of the mixed-valence biferrocenium iodides suggests that the rate of intramolecular electron transfer depends on the nature of biferrocenium cation moiety in solid state. 相似文献