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91.
92.
93.
We discuss a short-time existence theorem of solutions to the initial value problem for a third order dispersive flow for closed curves into a compact almost Hermitian manifold. Our equations geometrically generalize a physical model describing the motion of vortex filament. The classical energy method cannot work for this problem since the almost complex structure of the target manifold is not supposed to be parallel with respect to the Levi-Civita connection. In other words, a loss of one derivative arises from the covariant derivative of the almost complex structure. To overcome this difficulty, we introduce a bounded pseudodifferential operator acting on sections of the pullback bundle, and eliminate the loss of one derivative from the partial differential equation of the dispersive flow. 相似文献
94.
Ryu Sato Toshiyuki Fujio Shiduko Nakajo Satoshi Ogawa Ashraful Alam 《Tetrahedron letters》2007,48(17):3013-3016
The synthesis of benzopentathiepin having a hydroxyl group at the neighboring position of polysulfur ring was performed by demethylation of 6-ethyl-9-methoxybenzopentathiepin with hydrogenbromide. Benzotrithiole having hydroxyl group was not isolated at all. The hydroxyl group was also alkylated with alkyl iodide in the presence of weak base. 相似文献
95.
Hiramatsu H Kamiya T Tohei T Ikenaga E Mizoguchi T Ikuhara Y Kobayashi K Hosono H 《Journal of the American Chemical Society》2010,132(42):15060-15067
LaCuOSe is a wide band gap (~2.8 eV) semiconductor with unique optoelectronic properties, including room-temperature stable excitons, high hole mobility ~8 cm(2)/(Vs), and the capability of high-density hole doping (up to 1.7 × 10(21) cm(-3) using Mg). Moreover, its carrier transport and doping behaviors exhibit nonconventional results, e.g., the hole concentration increases with decreasing temperature and the high hole doping does not correlate with other properties such as optical absorption. Herein, secondary ion mass spectroscopy and photoemission spectroscopy reveal that aliovalent ion substitution of Mg at the La site is not the main source of hole doping and the Fermi level does not shift even in heavily doped LaCuOSe:Mg. As the hole concentration increases, the subgap optical absorption becomes more intense, but the increase in intensity does not correlate quantitatively. Transmission electron microscopy indicates that planar defects composed of Cu and Se deficiencies are easily created in LaCuOSe. These observations can be explained via the existence of a degenerate low-mobility layer and formation of complex Cu and Se vacancy defects with the assistance of generalized gradient approximation band calculations. 相似文献
96.
Shirakawa E Itoh K Higashino T Hayashi T 《Journal of the American Chemical Society》2010,132(44):15537-15539
Sodium tert-butoxide mediates the coupling of aryl halides with benzene derivatives without the aid of transition metal catalysts but with a catalytic 1,10-phenanthroline derivative. 相似文献
97.
Eiji Hashimoto Yuichi Seshimo Keita Sasanuma Yuichiro Aoki Hitoshi Kanazawa Yuji Ike Seiji Kojima 《Journal of Thermal Analysis and Calorimetry》2010,99(1):45-50
The fragility of ethylene glycol and glucose aqueous solution systems has been investigated by temperature-modulated differential
scanning calorimetry (TMDSC). The frequency and temperature dependences of complex specific heat have been observed in the
vicinity of a glass-transition temperature T
g
. It is shown that the value of the fragility index m can be determined from the temperature dependence of the α-relaxation times observed by TMDSC. We have also studied the elastic
properties of these aqueous solutions by micro-Brillouin scattering, and determined these relaxation times of elastic properties
in the gigahertz range. 相似文献
98.
Eiji Kobayashi Larisa S. Plashnitsa Takayuki Doi Shigeto Okada Jun-ichi Yamaki 《Electrochemistry communications》2010,12(7):894-896
All-solid-state phosphate symmetric cells using Li3V2(PO4)3 for both the positive and negative electrodes with the phosphate Li1.5Al0.5Ge1.5(PO4)3 as the solid electrolyte were proposed. Amorphous Li1.5Al0.5Ge1.5(PO4)3 was added into the electrode to increase the interface area between the active materials and the electrolyte. Any other phases were not formed at the electrode/electrolyte interface even after hot pressing at 600 °C. The discharge capacity was 92 mAh g? 1 at 22 µA cm? 2 at 80 °C, and 38 mAh g? 1 at 25 °C, respectively. Symmetric cell configuration leads to simplify the fabrication process for all-solid-state batteries and will reduce manufacturing costs. 相似文献
99.
100.
Tanaka H Sudo M Hirata M Etoh H Sato M Yamaguchi R Sakai E Chen IS Fukai T 《Natural product communications》2010,5(11):1781-1784
A new biisoflavonoid, biseryvarin A (1a), together with two known compounds were isolated from the roots of Erythrina variegata. The structure of biseryvarin A was established on the basis of spectroscopic evidence. Biseryvarin A is the first dimeric isoflavonoid possessing isoprenoid groups from the genus Erythrina. Biseryvarin A showed low activity against methicillin-resistant Staphylococcus aureus (MRSA). 相似文献