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71.
Akitami Ichihara Noriki Nio Yoshihiko Terayama Ryoji Kimura Sadao Sakamura 《Tetrahedron letters》1979,20(39):3731-3734
Various 2-alkyl-2-butenolactones were simply prepared from cyclopentadiene-maleic anhydride adducts through the retro-Diels-Alder reaction. The procedure was applied for the synthesis of dehydrolappaol A dimethyl ether. 相似文献
72.
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75.
Sadao Ikeda 《Annals of the Institute of Statistical Mathematics》1961,13(1):259-266
Summary In [1] the author treated a characterization problem of the ShannonWiener measure of information for continuous probability
distributions defined over an abstract measure space (R, S, m), wherem is a σ-finite measure over a σ-field S of subsets ofR, whose rangeM(S) is such thatM(S)=[0, ∞]. This condition on the range of the basic measure, however, can slightly be altered such thatM(S)=[0,1], and this modification is useful for characterization of the Kullback-Leibler mean information.
In the present paper, it is shown that the characterization procedure of [1] can be applicable to continuous probability distributions
defined on a finite measure space. 相似文献
76.
D. Nishimura Y. Fujita M. Fukuda E. Ganioğlu Y. Ichikawa M. Kanazawa A. Kitagawa M. Mihara S. Momota B. Rubio S. Sato G. Susoy M. Torikoshi K. Matsuta 《The European Physical Journal A - Hadrons and Nuclei》2011,47(12):1-7
A β-γ spectroscopy of the J π , 426 keV isomeric state of 24Al (24m Al) has been carried out by using a 24Al secondary beam with high purity and high isomeric ratio. From the absolute γ-ray and β-particle intensities observed in the decay of the isomeric state, the branching ratio R B of the isomeric γ decay from 24m Al to the J π = 4+, ground state of 24Al have been derived. The obtained R B value of 69.6(7)% is much smaller than the previously accepted value of 82.5(30)%. The precise half-life for the isomer decay, T 1/2 m = 130.9(13) ms, has been also determined in this experiment. Accordingly, the M3 γ-decay strength B(M3) of the 24m Al decay becomes smaller and the total β-decay branching ratio becomes larger. In particular, the β-decay branching ratio to the ground state of 24Mg becomes 24.3(9)%, which is 2.4 times larger than the previous value of 10.1(28)%. By combining the branching ratio and the half-life, the Gamow-Teller (GT) transition strength B(GT) of 0.0194(7) is deduced for the GT transition from 24m Al to the J π = 0+, ground state of 24Mg. This value is in good agreement with the values derived from charge-exchange reactions. 相似文献
77.
Treatment of 4-bromoisophorone with sodium methoxide gave 2-methoxyisophorone (4). Reaction of 4-chloroisophorone with sodium methoxide at 65–70° C afforded Favorskii-type rearangement product along with 4. 相似文献
78.
The cyclohexane ring-containing polyamide 1,3-CBMA-6 was synthesized from 1,3-cyclohexane-bismethylamine (1,3-CBMA) and adipic acid (6), and effects of cis/trans isomers of the ring on crystallinity and thermal properties were studied. Polymers with high cis and high trans contents, respectively, were made by polymerizing the 1,3-CBMA-6 salts of 98% cis and 93% trans derived from the salt of 75/25 (cis/trans) by fractional crystallization. A polymer with 97% cis content was highly crystalline, with a melting temperature of 253°C, while one with 93% trans contents was amorphous. In contrast to this, little difference was found in the glass transition temperature of 97 and 84°C. These results indicate that the isomers affect the conformation of the molecular chains, which determines the crystallinity and melting temperature, but they do not much affect the mobility of the chains as manifested by the glass transition. 相似文献
79.
Zen-ichi Yoshida Mitsuhiro Shibata Shuji Kida Sadao Miki Toyonari Sugimoto Shigeo Yoneda 《Tetrahedron letters》1984,25(3):345-348
The titled cationic systems with a doubly cross-conjugated 3-5-3 membered ring have been successfully synthesized. The change of electronic structure due to difference of substituent and substitution mode is discussed on the basis of their spectral data. 相似文献
80.
紫外可见光谱法研究脂质体结构形态与染料的相互作用 总被引:1,自引:0,他引:1
本文利用紫外可见光谱研究了脂质体的三种特定结构:胶束,层状相,反六方相与染料的相互作用。通过光谱的变化可检验脂质体的形态结构,筛选出4种可用于检测不同脂质体结构的染料。初步探索出一种利用染料检测脂质体结构相态的方法并探讨了染料与脂质体不同相态的作用机理。该方法有望作为一种简便快捷的检测手段,在分离天然磷脂及生产过程中控制脂质体形状结构中得到应用。 相似文献