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971.
Kazuo Hayakawa Yuki Akiyama Yoshinori Tsukamoto Mikio Kurata Kenichi Yukihira Hiroyoshi Soejima Yutaka Yoshida 《Hyperfine Interactions》2012,206(1-3):79-82
We have been developing a “M?ssbauer Spectroscopic Microscope (MSM)” which consists of a focusing lens for 14.4?keV γ-rays and a high precision X–Y stage. The measuring system both for electrons and γ-rays combined with a new M?ssbauer driver, i.e., “a moving coil actuator with a liner encoder” enables us to measure the mapping images simultaneously corresponding to different spectral components. The system has a controlling system based on a LabVIEW program and a LIST mode data acquisition system (NIKI-GLASS/A3100). To investigate a correlation between the microstructure of a sample and 57Fe atoms, a scanning electron microscope (APCO/Mini-EOC) is also installed to this system. 相似文献
972.
Yoshihisa Kurasawa Kiminari Yoshida Naoki Yamazaki Kotoji Iwamoto Yoshihiko Hamamoto Eisuke Kaji Kenji Sasaki Yoshito Zamami 《Journal of heterocyclic chemistry》2012,49(6):1323-1331
The 4‐quinolone‐2‐carboxylates 4a,b were converted into the 4‐quinolone‐2‐carbohydrazides 5a,b , hydrazones 6,7,10 , and related compounds 8,9,11 . The 4‐methoxyquinoline‐2‐carboxylate 12 was also transformed into the 4‐methoxyquinoline‐2‐carbohydrazide 13 , which was modified to the hydrazone 14 and related compound 15 . The antimicrobial activities of compounds 6b and 14 are described together with the 4‐oxo and 4‐hydroxy tautomers of compounds 4‐11 in deuteriodimethyl sulfoxide and deuteriotrifluoroacetic acid. 相似文献
973.
974.
Eri Yoshida 《Colloid and polymer science》2011,289(10):1127-1132
The nitroxide-mediated photo-controlled/living radical polymerization of ethyl acrylate was attained using (2RS,2′RS)-azobis(4-methoxy-2,4-dimethylvaleronitrile)
as the initiator, 4-methoxy-2,2,6,6-tetramethylpiperidine-1-oxyl as the mediator, and (4-tert-butylphenyl)diphenylsulfonium triflate as the photo-acid generator. The photopolymerization was performed in acetonitrile
at room temperature by irradiation with a high-pressure mercury lamp. The molecular weight distribution of the resulting polymer
decreased as the monomer concentration decreased. It was confirmed that the polymerization was controlled on the basis of
the linear correlations for the first-order time-conversion plots and the plots of the molecular weight vs. the reciprocal
of the initial concentration of the initiator, although the conversion–molecular weight plots did not show a completely linear
correlation. The block copolymerization with methyl methacrylate accompanied by no deactivation of the growing polymer chain
end supported the livingness of the polymerization. 相似文献
975.
The lemma given by Schmitt and Vogel is an important tool in the study of the arithmetical rank of squarefree monomial ideals.
In this paper, we give a Schmitt-Vogel type lemma for reductions as an analogous result. 相似文献
976.
Nitrogen-doped NaTaO3 was synthesized through 1-pot reaction, hydrothermal process using Ta3N5 as precursor. Changing concentration and amount of NaOH aqueous solution influenced nitrogen content in NaTaO3. Absorption edge of nitrogen-doped NaTaO3 was extended at 570 nm, and absorbance in visible light region depended on nitrogen content in NaTaO3. Anodic photocurrent measured under visible light irradiation became larger with increasing nitrogen content in NaTaO3-xNy. Under ultraviolet light irradiation (λ ≤ 400 nm), the highest anodic photocurrent was observed when nitrogen concentration was y = 0.024. It was possible to expand the wavelength range that can be effectively utilized for the photoelectrochemical reaction. 相似文献
977.
978.
The photoluminescence (PL) enhancement has been studied at room temperature using various specimen atmospheres (O2 gas, CO2 gas, CO2–H2 mixture gas, Ar–H2 mixture gas and vacuum) under 325 nm laser light irradiation on various metal oxides. Of them, the results obtained for BaTiO3 nanocrystals, SrTiO3 ones and HfO2 powder crystal are given in the present paper. Their PL were considerably increased in intensity by irradiation of 325 nm laser light in CO2 gas and CO2–H2 mixture gas. The cause of the PL intensity enhancements is discussed in the light of the exciton theory, the defect chemistry and the photocatalytic theory. The results may be applied for the utilization of greenhouse gas (CO2) and the optical sensor for CO2 gas. 相似文献
979.
980.