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121.
C.-A. Lee N. Tsukada A. Yamamoto T. Higuchi 《Applied Physics A: Materials Science & Processing》2008,91(3):445-450
The dependence of the liquid properties for fabricating convex microstructures on paraffin substrates using laser heating
is characterized. By analyzing the heat transfer from the material to the liquid, a highly linear relationship between the
heights of the fabricated microstructures and the heat-transfer coefficients is confirmed. In addition, the impact factor
of each liquid property is described. With this result, one can predict the features of the shapes of structures prior to
fabrication. Moreover, other parameters, such as the buoyant force and the substrate thickness, are also discussed.
PACS 07.10.Cm; 47.55.pf; 65.40.De; 79.20.Ds; 81.05.-t 相似文献
122.
Three ganglioside molecular species, OSG-0 (1), OSG-1 (2), and OSG-2 (3) have been obtained from the polar lipid fraction of the chloroform/methanol extract of the brittle star Ophiocoma scolopendrina. The structures of these gangliosides have been determined on the basis of chemical and spectroscopic evidence as 1-O-[(N-glycolyl-alpha-D-neuraminosyl)-(2-->6)-beta-D-glucopyranosyl]-ceramide (1), 1-O-[8-O-sulfo-(N-acetyl-alpha-D-neuraminosyl)-(2-->6)-beta-D-glucopyranosyll-ceramide (2) and 1-O-[(N-glycolyl-alpha-D-neuraminosyl)-(2-->8)-(N-acetyl- and N-glycolyl-alpha-D-neuraminosyl)-(2-->6)-beta-D-glucopyranosyl]-ceramide (3). The ceramide moieties were composed of heterogeneous unsubstituted fatty acid, 2-hydroxy fatty acid and phytosphingosine units. Compounds 2 and 3 represent new ganglioside molecular species. 相似文献
123.
124.
Hiroyuki Suga Satoshi Higuchi Daisuke Ishimoto Yuta Hashimoto Teruko Tsuchida Toshihide Baba 《Tetrahedron》2010,66(16):3070-6287
High enantioselectivities (94-96% ee) were obtained for the inverse electron-demand 1,3-dipolar cycloadditions between cyclohexyl vinyl ether and 2-benzopyrylium-4-olate generated via Rh2(OAc)4-catalyzed decomposition of o-methoxycarbonyl-α-diazoacetophenone. The reactions were effectively catalyzed by Eu(OTf)3, Ho(OTf)3, or Gd(OTf)3 complexes (10 mol %) of chiral 2,6-bis[(4S,5S)-4,5-diphenyl-2-oxazolinyl]pyridine. The reactions with the other electron-rich dipolarophiles such as allyl alcohol, 2,3-dihydrofuran, and butyl-tert-butyldimethylsilylketene acetal showed moderate enanantioselectivities (60-73% ee). Good to high enantioselectivities (73-97% ee) were also obtained for the cycloadditions between 3-acyl-2-benzopyrylium-4-olates, generated from methyl 2-(2-diazo-1,3-dioxoalkyl)benzoates and butyl or cyclohexyl vinyl ethers, in the presence of binaphthyldiimine (BINIM)-Ni(II) complexes (10 mol %). Under similar conditions, the reaction between methyl 2-(2-diazo-1,3-dioxohexyl)benzoate and 2,3-dihydrofuran was highly endo-selective, and moderately enantioselective (70% ee). For the BINIM-Ni(II)-catalyzed reactions of cyclohexyl vinyl ether, the use of an epoxyindanone as the 3-acyl-2-benzopyrylium-4-olate precursor revealed that the chiral Lewis acid can function as a catalyst for asymmetric induction. The scope of the cyclic carbonyl ylides was extended to those generated from 1-diazo-2,5-pentanedione derivatives, which were reacted with butyl or TBS vinyl ether and catalyzed using the (4S,5S)-Pybox-4,5-Ph2-Lu(OTf)3 complex to give good levels of asymmetric inductions (75-84% ee). 相似文献
125.
We propose Raman-induced collinear difference-frequency generation (DFG) as a method to manipulate dynamical magnetization. When a fundamental beam propagates along a threefold rotational axis, this coherent second-order optical process is permitted by angular momentum conservation through the rotational analogue of the umklapp process. As a demonstration, we experimentally obtained polarization properties of collinear magnetic DFG along a [111] axis of a single crystal of antiferromagnetic NiO with micromultidomain structure, which excellently agreed with the theoretical prediction. 相似文献
126.
Kierstead showed that every computable marriage problem has a computable matching under the assumption of computable expanding Hall condition and computable local finiteness for boys and girls. The strength of the marriage theorem reaches or if computable expanding Hall condition or computable local finiteness for girls is weakened. In contrast, the provability of the marriage theorem is maintained in even if local finiteness for boys is completely removed. Using these conditions, we classify the strength of variants of marriage theorems in the context of reverse mathematics. Furthermore, we introduce another condition that also makes the marriage theorem provable in , and investigate the sequential and Weihrauch strength of marriage theorems under that condition. 相似文献
127.
We have developed a novel synthetic method of phenylazomethine dendrons that uses 4,4'-methylenedianiline instead of 4,4'-diaminobenzophenone to synthesize the precursor of the phenylazomethine dendron and then oxidized the precursor to the next-generation dendron. For this method, the productivity of the dendrons has been significantly increased. Furthermore, as the synthesis of high-generation dendrons becomes easier, synthesis of DPA G5 was achieved. [structure--see text] 相似文献
128.
Saburo Higuchi 《Nuclear Physics B》1999,540(3):5677-741
A Hamiltonian cycle of a graph is a closed path that visits every vertex once and only once. It has been difficult to count the number of Hamiltonian cycles on regular lattices with periodic boundary conditions, e.g. lattices on a torus, due to the presence of winding modes. In this paper, the exact number of Hamiltonian cycles on a random trivalent fat graph drawn faithfully on a torus is obtained. This result is further extended to the case of random graphs drawn on surfaces of an arbitrary genus. The conformational exponent y is found to depend on the genus linearly. 相似文献
129.
130.