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41.
42.
Novel morphology titanate tubes were successfully synthesized via a self-assembly and self-removal process. After the product was treated by calcinating and washing, crystalline TiO2 tubes were obtained. In this study, two new concepts are applied to design the synthetic route: (i) titanium glycolate rods obtained from an ethylene glycol-mediated process and titanate sheets synthesized using the hydrothermal process were used as the template and the precursor, respectively, and ii) the template was directly removed in the reaction without posttreatment. Furthermore, a possible mechanism was proposed for the formation of tubular structures. 相似文献
43.
Ritsuko Matsukawa Kiyotaka Hatakeda Shota Ito Yukiyo Numata Hidetoshi Nakamachi Yasushi Hasebe Shunichi Uchiyama Masahiro Notoya Zvy Dubinsky Isao Karube 《Applied biochemistry and biotechnology》1999,80(2):141-150
Forty-eight species of seaweeds from Japanese waters were screened for the valuable polyunsaturated fatty acids eicosapentaenoic
acid (EPA). The eight species that contained the highest levels of these compounds were analyzed in detail. Of all species
tested the red alga Pachymeniopsis lanceolata contained the highest EPA concentration, and it was present as both the free and bound forms. EPA constituted 38.7% of total
fatty acids, and polar lipids were the main constituent of the total lipids in P. lanceolata. EPA was obtained from the marine algae P. lanceolata by enzymatic hydrolysis of the total lipids extract using phospholipase A2(PLA2). The release of EPA reached a plateau after 10 min of enzymatic treatment. These results suggest that P. lanceolata is a useful natural source of EPA and that PLA2 treatment is a convenient method for obtaining EPA from the red alga. 相似文献
44.
45.
Edwards AA Ichihara O Murfin S Wilkes R Whittaker M Watkin DJ Fleet GW 《Journal of combinatorial chemistry》2004,6(2):230-238
A furanose sugar amino acid (SAA) has been utilized as a library scaffold for the first time. Two furanose SAA scaffolds were examined to illustrate their potential for derivatization. The resulting 99-member library contained three orthogonal points of diversification that allowed easy access to ethers and carbamates from a hydroxyl moiety, a range of ureas from an azide (via an amine), and a range of amides from a methyl ester. The novel amide formation (by displacement of the methoxide from the methyl ester moiety) was achieved in good yield and purity with high structural confidence. Full characterization of several library intermediates (including a crystal structure) was obtained. The library was submitted for antibacterial screening. 相似文献
46.
Yoshihisa Kurasawa Ho Sik Kim Ritsuko Katoh Tae Kawano Atsushi Takada Yoshihisa Okamoto 《Journal of heterocyclic chemistry》1991,28(3):787-792
The reaction of the hydrazones 5a-c with 2-chloroacrylonitrile produced the 1,2-diazepino[3,4-b]quinoxaline hydrochlorides 6a-c , which were transformed into the 5,6,7,13-tetrahydro-5,14-methano-16-oxo-1,5,6-benzoxadiazonino[3,4-b]quinoxalines 7a-c , respectively. The oxidation of 7a-c with diethyl azodicarboxylate afforded the 7,13-dihydro-5,14-methano-16-oxo-1,5,6-benzoxadiazonino[3,4-b]quinoxalines 8a-c , respectively. Compounds 7a-c and 8a-c were also obtained by a one-pot synthesis from 5a-c and 6a-c , respectively. 相似文献
47.
A newly designed anthryl dendron having perfluoroalkyl chains at terminals showed thermotropic liquid crystallinity, which was characterized using polarizing optical microscopy, differential scanning calorimetry, and X-ray diffraction. The anthryl dendron forms SB phase at room temperature below 53 °C, at which temperature a phase transition to Colrd takes place. In a fluorous solvent, regioselective photodimerization of the anthryl dendron occurred to give head-to-head photodimers, although photodimerization in the SB phase and chloroform gave both head-to-head and head-to-tail photodimers. 相似文献
48.
Thermal decomposition behaviors of a fluororubber are observed with linear heating mode at constant rate, controlled rate mode and isothermal mode of TG/DTA, and, with isothermal mode of TG/mass-spectrometer. The results suggest that this material decomposes with, at least, three consecutive reactions. From the results of TG/DTA and TGMS in isothermal mode, it is considered that the first reaction is the first-order reaction, the second reaction is chain reaction and the last reaction is vaporization of residue. Supposing these three consecutive reactions, the decomposition behaviors of the rubber is simulated. The observed curves of fraction of mass loss, , against time, t, are well reproduced by the simulation. The relationship between d/dt and is reproduced also, though the differences between observed and the calculated values of d/dt are slightly larger than noise level of d/dt. 相似文献
49.
M. Takeuchi T. Takano S. Ichihara Y. Takasu M. Kumakura T. Yabuzaki Y. Takahashi 《Applied physics. B, Lasers and optics》2006,83(1):107-114
We report the observation of paramagnetic Faraday rotation of spin-polarized ytterbium (Yb) atoms. As the atomic samples,
we used an atomic beam, released atoms from a magneto-optical trap (MOT), and trapped atoms in a far-off-resonant trap (FORT).
Since Yb is diamagnetic and includes a spin-1/2 isotope, it is an ideal sample for spin physics, such as quantum non-demolition
measurement of spin (spin QND), for example. From the results of the rotation angle, we confirmed that the atoms were almost
perfectly polarized.
PACS 32.80.Bx; 32.80.Pj; 42.25.Lc 相似文献
50.
H. Okuno K. Asahi H. Ueno H. Sato M. Adachi T. Kubo T. Nakamura N. Inabe A. Yoshida Y. Ohkubo T. Ichihara M. Ishihara T. Shimoda H. Miyatake N. Takahashi 《Hyperfine Interactions》1993,78(1-4):97-103
A method to produce beams of polarized unstable nuclei was developed, which fully exploits the advantageous features of the projectile fragmentation reaction. The method was applied tog-factor measurements of several neutron-rich nuclei. We present experimental results so far obtained and discuss capabilities and limitations the present polarization method has. 相似文献