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991.
Itsuo Mori Yoshikazu Fujita Minako Toyoda Miyoko Hamada Masao Akagi 《Fresenius' Journal of Analytical Chemistry》1992,343(12):902-904
Summary A simple and sensitive determination of cobalt(II) is based on its fluorescence reaction with p-hydroxy-2-anilinopyridine and hydrogen peroxide. The relative standard deviation is 2.5% (n=5). An application to pharmaceutical preparations is recommended.The application of diarylamine compounds in analytical chemistry. IV.-Part III see ref. [1] 相似文献
992.
993.
994.
Tadakatsu Mandai Kazuhito Mori Keisuke Hasegawa Mikio Kawada Junzo Otera 《Tetrahedron letters》1984,25(46):5225-5226
A novel synthetic method for α-methylene-γ-butyrolactones involving a thioallylic rearrangement as a key step was developed. 相似文献
995.
996.
Keiji Takeda Hiroko Tokoro Fumiyoshi Hakoe Akira Yamaguchi Hatsumi Mori Hidehiko Ishimoto Takayoshi Nakamura Shinya Kuriki Shin-ichi Ohkoshi 《Polyhedron》2009,28(9-10):1746-1749
We have developed a high temperature superconductor (HTS) micro SQUID magnetometer for molecular-based magnets. By employing the dipole approximation, we verified the flux value of 40Φ0 from the saturation magnetic moment of the ferrimagnetic microcrystal of [Mn2(H2O)2(CH3COO)][W(CN)8] · 2H2O (15 × 15 × 13 μm). Considering the relative arrangement of the sample and the SQUID loop, including the influence of the film and grease, the calculated the flux values were Φ = 71Φ0 and 31Φ0 at distances of 20 and 30 μm between the sample bottom face and the SQUID plane, respectively. Thus, the experimentally obtained flux value is reasonable. 相似文献
997.
998.
To evaluate the influence of a printed wiring board (PWB) with a high coefficients of thermal expansion (CTE) on the thermal deformation of a small outline J-leaded electronic package (SOJ), a newly developed phase-shifting method was applied to moiré interferometry. This phase-shifting moiré interferometry method uses a wedged glass plate as a phase shifter to obtain displacement fields with a sensitivity of 100 nm/line. This technique also enabled the quantitative determination of strain distributions in all observation areas. Thermal loading was applied from room temperature (25 °C) to an elevated temperature (100 °C), and then the thermal strains of SOJ with and without the PWB were compared. The results showed that the concentrations of the longitudinal strains εxx and εyy became increasingly prominent when mounted on the PWB, and the shear strains γxy were concentrated at the corners of the silicon chip. The values of these strains increased by about 50% when the SOJ was mounted on the PWB. 相似文献
999.
Toshimasa Katagiri Michiharu Handa Hiroyuki Asano Teppei Asanuma Tomohiro Mori Tatsuya Jukurogi Kenji Uneyama 《Journal of fluorine chemistry》2009,130(8):714-717
Preparations and reactions of a series of 2-trifluoromethylketenimines are described. Trifluoromethylketenimines were prepared from trifluoropropanoic acids via corresponding imidoyl chlorides in good yields. 2-Trifluoromethylketenimine was functionalized at its β-position by electrophilic addition of halide, followed by dehydrohalogenation. Addition of nucleophile at α-position gave trifluoroethylated β-amino acid derivative via 1,3-proton shift. 相似文献
1000.
Three twin types of troponoid liquid crystals, in which the directions of the tropone carbonyl groups are different from each other, were prepared to establish their thermal properties. Symmetrical type I dimers, in which the two tropone carbonyl groups are directed inwards, had monotropic smectic C phases, whereas two other symmetrical type IIa and IIb dimers, whose troponoid dipoles are directed outwards, were not mesomorphic except for one type IIa compound having two long terminal chains and a short alkylene spacer. Unsymmetrical type III dimers had smectic A phases. Among the dimers, unsymmetrical type III dimers had the highest clearing point when the number of atoms of the inner and outer spacers was fixed. X-ray diffraction studies of a type III dimer, in which the number of the atoms of the inner spacer was odd, showed that the molecules form an interdigitated layer structure. The binary system between type I and type IIb dimers showed an induced enantiotropic smectic A phase, in which the dipole moments of the tropone rings were cancelled. 相似文献