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181.
In this paper, we completely determine the diffeomorphism types of the 5‐dimensional links of 3‐dimensional log‐canonical singularities defined by Brieskorn polynomials. Moreover, we show that if k is an integer with 1 ≤ k < 611, then there is no link K defined by a Brieskorn polynomial in ?4 such that the order of H2(K) is 6k. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
182.
This paper builds on a formal theory of how certain observable properties of images of stratification and self‐location within an image are generated in ordinary social interactioa The new element is the attention to shape, involving the transformation of an actual distribution of actors in class locations into some distribution image. Such an image may resemble a simple form, such as a diamond or pyramid. As in all our work, such images depend upon the actor's class location. We derive general results and analyze a number of special cases in detail. 相似文献
183.
Osamu Horie Yasuhiko Syono Yasuaki Nakagawa Atsuko Ito Kiyohito Okamura Seishi Yajima 《Solid State Communications》1978,25(7):423-426
HomogeneousBaO?Fe2O3?B2O3 glasses containing maximum Fe2O3 content of 63 mol.% are prepared by splat cooling technique. Mössbauer study reveals that the glass mainly consists of tetrahedral network of Fe3+O4. Mössbauer spectrum of the glass shows a well defined hyperfine structure at low temperatures. Magnetic ordering temperature estimated is about 130 K for the most iron-rich specimen, being much lower than that of the corresponding crystalline phases, BaO;·;Fe2O3 and BaO·;2Fe2O3. The magnetic structure is suggested to be of a short-range antiferromagnetic ordering. 相似文献
184.
Takao Yamazaki Katsuhide Matoba Atsuko Shirokawa Raymond N. Castle 《Journal of heterocyclic chemistry》1978,15(3):467-471
The reaction of ethyl 3,4-dihydro-4-quinazolylacetate ( 1a ) with cyclopentanone in the presence of trifluoroacetic acid gave mainly two decomposition products, carbostyril (VIII) and ethyl 2-aminocinnamate (IX). Two compounds which are suggested to have the 6,8-diazasteroid skeleton were also obtained in poor yield. Ethyl 3,4-dihydro-2-p-methoxyphenyl-4-quinazolylacetate (1b), however, gave 2-p-methoxyphenylquinazoline (XII) as a decomposition product and did not condense with cyclopentanone. Furthermore, two ethyl 3,4-dihydroquinazolylacetates substituted at the 2-position with cyclohexyl (1c) and methyl (1d) groups could not be converted to the expected diazasteroid system. 相似文献
185.
Kazunori Kadota Takenobu Yamamoto Atsuko Shimosaka Yoshiyuki Shirakawa Jusuke Hidaka Masato Kouzu 《Journal of nanoparticle research》2011,13(12):7209-7218
The mechanism on aggregation of spindle granular particles of calcite was investigated for the carbonation of calcium hydroxide
in aqueous suspension for the purpose of controlling morphology of CaCO3. The experimental carbonation process was carried out in a semi-batch bubble column reactor under different conditions. Although,
fine rhombic nano-particles diameter ranged from 100 to 200 nm were obtained at 291 K, a higher temperature of 300 K provided
spindle granular particles with a length of 1.0–1.5 μm and a width of 0.3–0.5 μm. The average crystallite size was 28 nm for
the fine rhombic nano-particles and 43 nm for the spindle granules. Zeta potential measurement for the spindle granules indicated
that the suspension tended to be aggregated during the carbonation process. The effect of the degree of particle aggregation
on the shape of the obtained calcite particles was studied by Monte Carlo simulations. Our simulation results elucidated the
dependence of aggregation on unit particles, i.e., primary particles, on the experiment carbonation condition where the spindle
granules were formed out of the unit particles under the same condition as the experiments. In addition, the formation mechanism
of the granules was investigated by applying classical nucleation theory to the present simulations. 相似文献
186.
The catalytic asymmetric Friedel-Crafts/protonation of indoles and pyrroles with α-substituted nitroalkenes to give the corresponding adducts in a highly anti-selective manner was achieved by an imidazoline-aminophenol (L2)-Cu complex. The anti-adducts could be successfully transformed to biochemically important α-substituted β-heteroarylalkylamines. 相似文献
187.
A new strategy for synthesizing quinolizidine skeletons by reductive cyclization via acylpyridinium cations was developed. Several functional groups, including carbonyl, silyl, and acetal, were tolerated under mild reaction conditions. The reaction was successfully extended to a one-pot synthesis of a bicyclic compound, and the synthetic strategy was applied to concise total syntheses of quinolizidines 207I and 1-epi-207I, without protecting groups. 相似文献
188.
189.
Tatsuya Yamamoto Kazuyuki Kinoshita Nobuyuki Kosaka Yoshitaka Sato Hiroki Shioura Hiroaki Takeuchi Hirohiko Kimura 《Magnetic resonance imaging》2013,31(8):1271-1277
IntroductionTechnological developments have increased the ease of performing perfusion MRI by arterial spin labeling (ASL) in clinical settings. The objective of this study was to evaluate the effects of radiotherapy on extra-axial brain tumors by using MR perfusion images obtained using the pseudo-continuous arterial spin labeling (pcASL) method.Materials and MethodsSix consecutive patients (nine lesions) with extra-axial brain tumors treated only with radiotherapy were enrolled in this study. MR examinations, including pcASL imaging, were performed before and after radiotherapy. Cerebral blood flow, maximum tumor blood flow (mTBF), tumor volume and the ratio of signal enhancement by contrast material (enhancement ratio) were evaluated in serial examinations during the course of radiotherapy. Both the percentage change in mTBF (mTBF ratio) and the percentage change in volume (volume ratio) were calculated using values obtained before and after radiotherapy. The correlation between the volume ratio and the mTBF ratio was assessed using linear regression analysis and Spearman’s rank correlation coefficient (rs).ResultsA strong correlation was demonstrated between the tumor volume ratio and the mTBF ratio before and after radiotherapy (rs= 0.93, P< .01). However, no significant correlation was identified between changes in enhancement and volume ratio (rs= 0.20) or between changes in enhancement and mTBF ratio (rs= 0.30) before and after radiotherapy.ConclusionThe mTBF measured using pcASL may serve as an additive index for tumor volume when determining tumor response to radiotherapy even in the absence of contrast material. 相似文献
190.
Hiromichi Hayashi Akiko Ueda Atsuko Suino Kyoko Hiro Yukiya Hakuta 《Journal of solid state chemistry》2009,182(11):2985-2990
Yttria stabilized zirconia nanoparticles have been prepared by hydrothermal flow reaction system under subcritical and supercritical conditions. ZrO(NO3)2/Y(NO3)3 mixed solutions were used as starting materials. Reaction temperature was 300–400 °C. Reaction time was adjusted to 0.17–0.35 s. Based on the residual Zr and Y concentrations, the complete conversion of zirconium was achieved irrespective of pH and hydrothermal temperature, whereas the conversion of yttrium increased with an increase in pH and hydrothermal temperature. Stoichiometric solid solution was achieved at pH>8. XRD results revealed that tetragonal zirconia can be formed regardless of yttrium content, where the tetragonality was confirmed by Raman spectroscopy. The average particle size estimated from BET surface area was around 4–6 nm. Dynamic light scattering particle size increased with the solution pH owing to the aggregation of primary particles. TG-DTA analyses revealed that weight losses for adsorbed water and hydroxyl groups decreased with hydrothermal temperature. 相似文献