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61.
The perfect all-anti-octasilane composed of two bicyclic trisilane units with trimethylsilyl groups at the termini has been synthesized. Its X-ray crystal structure and spectroscopic data demonstrate the effective sigma-delocalization over the silicon framework, which is a definitive difference from the unconstrained n-Si8Me18. 相似文献
62.
Sato K Egami A Odake T Tokeshi M Aihara M Kitamori T 《Journal of chromatography. A》2006,1111(2):228-232
A cellular biochemistry analysis system was integrated on a quartz glass microchip with a microchamber for cell culture followed by a microchannel for detecting with a thermal lens microscope (TLM). Nerve cells from rat hippocampus were successfully cultured to form neural networks in the microchip. An aqueous solution of glutamate, which is known as a neurotransmitter, was introduced to stimulate the cultured neuron to release a retrograde messenger, arachidonate which is considered to be critical for neuronal plasticity, especially for long-term potentiation (LTP). After the introduction, the solution that flowed through the culture chamber was analyzed using the UV-TLM (excitation wavelength, 244 nm). The measured signal intensity was dependent on glutamate solution concentration, and the neurons were considered to release the retrograde messenger according to the glutamate concentration. This system is suitable for time-course monitoring of ultra trace amounts of chemicals released from very small amount of cultured cells. 相似文献
63.
[reaction: see text] We synthesized zigzag polymers consisting of dithia[3.3](2,6)pyridinophane units that were flipped rapidly as a result of syn-[anti]-syn isomerization. Pyridinophane units were fixed in the syn form by complexation with palladium, and the resulting polymer complex exhibited a high catalytic activity for the Heck coupling reaction. 相似文献
64.
65.
Hiromi Takiguchi Azusa Tsubata Makoto Miyata Tamao Odake Hiroki Hotta Tomonari Umemura Kin-ichi Tsunoda 《Analytical sciences》2006,22(7):1017-1019
A flow injection analysis system was built with a liquid core waveguide spectrophotometric detector using an 80 cm Teflon AF-1600 capillary tube (2,2-bistrifluoromethyl-4,5-difluoro-1,3-dioxole/tetrafluoroethylene). The system was applied to determine nitrite ion in river water samples. The lower limit of detection for nitrite was 2.1 nmol dm(-3) (0.1 ng dm(-3) as NO(2)(-)) and the relative standard deviation of measurements was typically 0.56% (n = 5) at 0.21 micromol dm(-3). 相似文献
66.
Tamao Ishida Yuta Onuma Kota Kinjo Akiyuki Hamasaki Hironori Ohashi Tetsuo Honma Tomoki Akita Takushi Yokoyama Makoto Tokunaga Masatake Haruta 《Tetrahedron》2014
Palladium nanoparticles (Pd NPs) encapsulated by conjugated microporous polymers (CMPs) were prepared by the Pd-catalyzed polymerization followed by a thermal treatment with N2 or H2. The Pd catalysts were embedded in the porous network during polymerization and used as a precursor for the generation of Pd NPs in CMP. Although no Pd NPs were formed in the as-synthesized Pd/CMPs, Pd NPs with 1.6–3.5 nm size were formed after the thermal treatment. The obtained Pd/CMP-N2 and -H2 catalysts were highly selective in the hydrogenation of 4-nitrostyrene to 4-ethylnitrobenzene, whereas Pd NPs supported on carbon (Ketjen black) gave a fully reduced product, 4-ethylaniline. Substituents in CMP framework could change the catalytic activity of Pd NPs; hydroxy-substituted CMP encapsulated Pd NPs showed higher catalytic activity than Pd/CMP-H2 for benzyl alcohol oxidation. 相似文献
67.
Jun'Ichi Shiraishi Harunobu Kubo Hidetoshi Awata Satoru Odake 《Letters in Mathematical Physics》1996,38(1):33-51
A quantum deformation of the Virasoro algebra is defined. The Kac determinants at arbitrary levels are conjectured. We construct a bosonic realization of the quantum deformed Virasoro algebra. Singular vectors are expressed by the Macdonald symmetric functions. This is proved by constructing screening currents acting on the bosonic Fock space. 相似文献
68.
(E)-Alkenylpentafluorosilicates, obtainable from acetylenes via hydrosilylation-silicate formation, react with alcohols in the presence of a catalytic amount of copper(II) acetate under an atmosphere of air (oxygen) at room temperature to form (E)-alkenyl ethers stereoselectively in satisfactory yields. Similar reaction with water gives aldehydes. 相似文献
69.
Nucleophilic hydroxymethylation of aldehydes and ketones has been achieved by the reaction with the (isopropoxydimethylsilyl)methyl Grignard reagent and the subsequent oxidative cleavage of the carbon-silicon bond. 相似文献
70.