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991.
Hisamitsu Akamaru Akifumi Onodera Tadashi EndoOsamu Mishima 《Journal of Physics and Chemistry of Solids》2002,63(5):887-894
Effect of pressure on the band gaps on AlN and graphite-type BN (g-BN) has been studied up to 2.7 GPa at room temperature by measuring the optical-absorption edge of single crystals of each substance pressurized in a sapphire-anvil cell. The direct band gap of AlN shifted towards higher energy at a rate of 49±1 meV/GPa, whereas in g-BN the pressure dependence of the band gap was −36±1 meV/GPa. The results are compared with existing first-principles calculations. 相似文献
992.
Hirano Morio Mori Hirofumi Miura Yuuki Matsunaga Naoki Nakamura Noriyuki Matsunaga Tadashi 《Applied biochemistry and biotechnology》1990,(1):183-191
The production of γ-linolenic acid from algae in fresh and marine water was investigated. WhenSpirulina platensis was left in the dark condition, it contained about one and a half times γ-linolenic acid compared with conventionalSpirulina platensis. Marine microalga,Chlorella sp. NKG 042401 contained about 10% of γ-linolenic acid. The highest γ-linolenic acid content was obtained when this alga was
cultured under the radiation of around 100 μEinstein/m2/s. 相似文献
993.
994.
995.
996.
Several 4-oxa- and -aza-bird-cage compounds were prepared by transannular cyclizations of pentacyclo[6.2.1.0.2,70.4,1005,9]undecan-3,6-dione (3). Diol derivatives of 3 cyclized to afford the corresponding 4-oxa-bird-cage derivatives such as 9, 16a and 16b. The corresponding 3-keto-6-ol derivatives (6, 10a and 10b) did not cyclize transannularly, while 3-imino-6-ol, 3-keto-6-amino, and 3- imino-6-amino type derivatives cyclized to afford 3-substituted 4-oxa- and -aza-bidr-cage compounds such as 12, 14 and 18. The transannular cyclization reactivity in the 3 system has been compared with that in the bicyclo[3.3.1]nona-3,7-dione system (1). 相似文献
997.
Tatsuya Shono Yoshihiro Usui Tadashi Mizutani Hiroshi Hamaguchi 《Tetrahedron letters》1980,21(32):3073-3076
Controlled potential reduction of immonium salts in the presence of bromo esters such as o-bromomethyl benzoates has afforded annellated products. The method is applicable to the synthesis of berbine alkaloids. 相似文献
998.
999.
Tohru Eguchi 《Nuclear Physics B》1974,70(3):390-396
By constructing exact exchange-degenerate solutions of baryons with the harmonic-oscillator spectrum for a set of reactions MB→M′B′, MB → M′D′ and MD → M′D′, we investigate the duality constraints on the amplitude signs in MB → M′D′. It is shown that the amplitude signs determined by duality are consistent with those predicted by the extended version of SU(6)W symmetry with the universal dominance of the ΔLZ = 0 or ΔLZ = ±1 amplitude in the mesonic transitions of the baryons. 相似文献
1000.
Shinto Eguchi 《Annals of the Institute of Statistical Mathematics》1991,43(2):245-260
This paper is concerned with the theory of testing hypothesis with composite null hypothesis or with nuisance parameters. The asymptotic behaviour of the likelihood ratio and the associated test statistics are investigated. Under a class of local alternatives with local orthogonality relative to the nuisance parameter vector, a unique decomposition of local power is presented. The decomposition consists of two parts; one is the influence of nuisance parameters and the other is the power corresponding to the simple case where the nuisance parameters are known. The decomposition formula is applied to some examples, including the gamma, Weibull and location-scale family. 相似文献