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71.
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Let f : U → X be a map from a connected nilpotent space U to a connected rational space X. The evaluation subgroup G
*(U, X; f), which is a generalization of the Gottlieb group of X, is investigated. The key device for the study is an explicit Sullivan model for the connected component containing f of the function space of maps from U to X, which is derived from the general theory of such a model due to Brown and Szczarba (Trans Am Math Soc 349, 4931–4951, 1997).
In particular, we show that non Gottlieb elements are detected by analyzing a Sullivan model for the map f and by looking at non-triviality of higher order Whitehead products in the homotopy group of X. The Gottlieb triviality of a fibration in the sense of Lupton and Smith (The evaluation subgroup of a fibre inclusion, 2006)
is also discussed from the function space model point of view. Moreover, we proceed to consideration of the evaluation subgroup
of the fundamental group of a nilpotent space. In consequence, the first Gottlieb group of the total space of each S
1-bundle over the n-dimensional torus is determined explicitly in the non-rational case.
相似文献
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Nobuyuki Takeyasu Takayuki Deguchi Manami Tsutsumikawa Junichi Matsumoto Totaro Imasaka 《Analytical sciences》2002,18(3):243-246
A distributed-feedback dye laser with a quenching cavity was designed and constructed for generating a tunable picosecond pulse with a narrow spectral linewidth. This nearly transform-limited pulse was succeedingly amplified by a triple-pass off-axis amplifier. The pulse duration and the spectral linewidth were 60 ps and 9.4 pm, respectively. The amplified pulse was frequency-doubled by second-harmonic generation, producing a 0.5-mJ pulse with no background emission. The potential advantage of this laser in the analysis of dioxin based on supersonic jet/resonance-enhanced multiphoton ionization/mass spectrometry is discussed. 相似文献
77.
Jnn'ichi Toei Keizen Fujii Nobuyuki Baba 《Fresenius' Journal of Analytical Chemistry》1989,334(1):13-15
Summary A new type reaction valve for flow injection analysis has been developed. In a FIA system with this valve the injected sample is once passed into a loop of the valve, thereafter the valve is rotated to the next position. Therefore, the sample is retained in the loop in a stop-state for a long time and the next sample is introduced into another loop in the next position. When the valve is rotated for one round, the stopped sample in the fist loop is again passed into the detector flow cell. Thus, an analysis, which needs a long reaction time, can be performed with this valve with high precision.
Verbessertes Reaktionsventil für die Flie\injektionsanalyse相似文献
78.
We shall study the relation between the unstable homotopy spectral sequence associated with the cell decomposition of the source space and the one associated with the Postnikov decomposition of the target space. It is proved that the Maunder's result holds for these two types of spectral sequences. This result will be exploited to study the differentials of these spectral sequences and we obtain a generalization of a theorem due to Atiyah-Hirzebruch and Dold. Making use of these spectral sequences with the convergence lemma, some results on the phantom maps and the homotopy groups of map*(Y, X) will be proved. 相似文献
79.
Sang Ju Lee Seung Jun Oh Eun Hye Cho Da Hye Kim Shozo Furumoto Nobuyuki Okamura Jae Seung Kim 《Journal of Radioanalytical and Nuclear Chemistry》2017,314(3):1587-1593
[18F]THK-5351, a new candidate for tau protein imaging, is based on an aryl quinoline structure. We report the full automatic synthesis using disposable cassettes under pH controlled [18F]fluorination. After the trapping of 88.5 ± 21.9 GBq of [18F]fluoride, it was eluted with potassium methansulfonate (KOMs) (pH 7.8)/K222. After drying, 3 mg of the precursor was added to 1 mL DMSO and subjected to [18F]fluorination at 110 °C for 10 min. After hydrolysis, the final product was purified by HPLC. The overall radiochemical yield was 31.9 ± 11.1% (n = 22), satisfying all quality control criteria. It was stable for up to 6 h with high radiochemical purity as 99.8 ± 0.5%. 相似文献
80.
Nobuyuki Tamaoki Takashi Kamei 《Journal of Photochemistry and Photobiology, C: Photochemistry Reviews》2010,11(2-3):47-61
Photochromic reactions in liquid crystals induce re-alignments of the host molecules, accompanied by changes in the optical properties and various other properties of the materials. Since the first report by Sackmann in 1971, various combinations of photochromic compounds and liquid crystals have been studied to elicit the reversible photo-regulated changes of various properties. In this report we review the advances of this field during the past 5 years, which include the creation of mechanical functions, the regulation of novel optical properties, cholesteric liquid crystals doped with azobenzene compounds in high concentrations, the regulation of ferroelectric liquid crystals, the induction of chirality by circularly polarized light, photoresponsive chiral dopants, and the photo-regulation of the oscillation wavelength of mirrorless lasers. 相似文献