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991.
Ohyabu N Ida K Morisaki T Narihara K Komori A Watanabe K Narushima Y Nagayama Y Shoji M Ashikawa N Emoto M Funaba H Goto M Idei H Ikeda K Inagaki S Inoue N Isobe M Khlopenkov K Kobuchi T Kostrioukov A Kubo S Kumazawa R Liang Y Masuzaki S Minami T Miyazawa J Morita S Muto S Mutoh T Murakami S Nakamura Y Nakanishi H Nishimura K Noda N Notake T Ohkubo K Ohdachi S Oka Y Osakabe M Ozaki T Peterson BJ Sakamoto R Sakakibara S Sagara A Saito K Sasao M Sato K Sato M Seki T Shimozuma T Sudo S Suzuki H 《Physical review letters》2002,88(5):055005
In the Large Helical Device plasma discharges, the size of an externally imposed island with mode number ( n/m = 1/1) decreases substantially when the plasma is collisionless ( nu(*)< approximately 1) and the beta is finite ( > approximately 0.1%) at the island location. For the collisional plasmas with finite beta, on the other hand, the size of the island increases. However, there is a threshold in terms of the vacuum island size below which the island enlargement is not seen. 相似文献
992.
993.
Nishikawa H Morimoto T Kodama T Ikemoto I Kikuchi K Yamada J Yoshino H Murata K 《Journal of the American Chemical Society》2002,124(5):730-731
The synthesis and electrochemical properties of a new organic donor, (1,4-dioxan-2,3-diyldithio)dihydrotetrathiafulvalene (DODHT), and the crystal structures and physical properties of its superconducting salts are described. The DODHT molecule has the bulky dioxane ring condensed by cis fusion, and the reduced pi-electron system of DODHT, as compared with conventional tetrachalcogenafulvalene donors, leads to both the weak electron-donating ability and the large on-site Coulomb energy. Nevertheless, DODHT produces the superconducting AsF6 and PF6 salts, which are isostructural and exhibit superconducting transitions at 3.3 and 3.1 K, respectively, under 16.5 kbar. 相似文献
994.
Furukawa S Takagi N Ikeda T Ono M Nafady AM Nohara T Sugimoto H Doi S Yamada H 《Chemical & pharmaceutical bulletin》2002,50(3):439-440
Two new long-chain alkanoic acid esters of lupeol were isolated together with known triterpenoids, alpha-amyrin, beta-amyrin, cycloartenol, lanosta-7,24-diene-3beta-ol and lupeol from Alecrim-propolis collected in Brazil. The structures were characterized by spectroscopic means. 相似文献
995.
Psilocin analogs having either a formyl group (9-12) or a bromine atom (13-18) at the 5- or 7-position have been prepared for the first time. Syntheses of 5- and 7-bromo derivatives of 4-hydroxy- (23, 24, 28) and 4-benzyloxyindole-3-carbaldehyde (19, 25, 29, 30), 4-benzyloxyindole-3-acetonitriles (20, 31), and 4-benzyloxy-N,N-dimethyltryptamine (32, 34, 35) have also been established. 相似文献
996.
Yamada K Sasaki K Harada Y Isobe R Higuchi R 《Chemical & pharmaceutical bulletin》2002,50(11):1467-1470
Ten glucocerebrosides, HPC-3-A-HPC-3-J, have been isolated from their obtained parent glucocerebroside molecular species HPC-3, together with other glucocerebroside molecular species HPC-1 and HPC-2, from the less polar lipid fraction of a chloroform/methanol extract of the sea cucumber Holothuria pervicax. The structures of these glucocerebrosides have been determined on the basis of chemical and spectroscopic evidence. Reversed-phase HPLC, including a recycling system, was effective in isolating these glucocerebrosides, revealing a very close resemblance in structure, though the problem due to regio-isomers remains. 相似文献
997.
Anthracene derivatives with several TEMPO radicals (2-4, 10) were prepared, and each photodimerization reaction was investigated. Although the photodimerization was unsuccessful in obtaining the dimers of anthracenes 2 and 3, which could be alternatively prepared in a stepwise manner, the photodimers of anthracenes 4 and 10 were available by the direct photoreaction. The dissociation reaction of the dimers proceeded well by heating them in solution to give the corresponding monomers in each case, and thus the reversible system could be constructed in the latter two systems. While no large difference was observed in their magnetic behaviors between the monomer/dimer pair of 4 and 8, an intriguing difference was found in the magnetic behaviors for the pair of 10 and 11 from ferromagnetic interactions in 10 to the variable magnetic interactions in 11 depending on the solvent molecules incorporated in the crystals. 相似文献
998.
Yamakawa M Yamada I Noyori R 《Angewandte Chemie (International ed. in English)》2001,40(15):2818-2821
999.
Three-dimensional hole drilling of silica glass from the rear surface with femtosecond laser pulses 总被引:4,自引:0,他引:4
By moving silica glass in a preprogrammed structure, we directly produced three-dimensional holes with femtosecond laser pulses in single step. When distilled water was introduced into a hole drilled from the rear surface of the glass, the effects of blocking and redeposition of ablated material were greatly reduced and the aspect ratio of the depth of the hole was increased. Straight holes of 4-mu;m diameter were more than 200 microm deep. Three-dimensional channels can be micromachined inside transparent materials by use of this method, as we have demonstrated by drilling a square-wave-shaped hole inside silica glass. 相似文献
1000.
Experimental tie-line data have been determined for the ternary system water + methyl tert-butyl ether + tert-amyl methyl ether and the quaternary systems water + methanol + methyl tert-butyl ether + tert-amyl methyl ether, and water + ethanol + methyl tert-butyl ether + tert-amyl methyl ether at 25°C and ambient pressure. The experimental results have been satisfactorily correlated using the modified UNIQUAC and extended UNIQUAC models with ternary and quaternary, in addition to binary parameters. 相似文献