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81.
Matsuoka H Shimoda S Miwa Y Saito M 《Bioelectrochemistry (Amsterdam, Netherlands)》2006,69(2):187-192
A 2-channel (2C) microinjector was prepared by pulling a glass capillary with a theta-shaped cross section. One channel was used as a potential measuring electrode (MeaE) and the other was used as an electrophoretic introduction electrode (IntE). The 2C microinjector was propelled by an oil pressure manipulator driven by a pulse motor, while the MeaE output was recorded continuously. When the 2C microinjector penetrated the cell membrane of a mouse ES cell or a rice protoplast, the output potential changed sharply. The differential of this potential change was used as a stop signal for the pulse motor. Thus, the microinjector was correctly positioned in the cell without losing cell viability. Its success rate was 73% and 84% for ES cells and rice protoplasts, respectively. After the positioning of the microinjector in the cell, Lucifer yellow (LY) was introduced via IntE. Under these conditions, the rate of viable cells was 16% and 62% for ES cells and rice protoplasts, respectively. 相似文献
82.
Dr. Sigma Hashimoto Soichiro Nakatsuka Prof. Dr. Masaharu Nakamura Prof. Dr. Takuji Hatakeyama 《Angewandte Chemie (International ed. in English)》2014,53(51):14074-14076
A P‐fused double helicene consisting of a highly distorted benzene ring, with a bending angle of 23°, has been synthesized by a tandem intramolecular phospha‐Friedel–Crafts reaction. Despite the distortion and reduced aromaticity, the double helicene shows thermal and chemical stability. These are important features that make these compounds attractive for applications as a new C2‐symmetric bisphosphine ligand. The simple strategy proposed in this work can be used to prepare a diverse range of distorted molecules. 相似文献
83.
The paper studies effect of momentum injection, accomplished through circular cylindrical rotating elements, on the pressure distribution at the roof of a model house. Extensive wind tunnel tests, complemented by flow visualization, suggest that such Moving Surface Boundary-layer Control (MSBC) effectively delays separation and significantly increases the pressure, both on leeward and windward surfaces. This would assist in protection of the roof against wind storms and snow accumulation. 相似文献
84.
Yoshiro Tatsu Soichiro Yamamura Hitoshi Yamamoto Susumu Yoshikawa 《Fresenius' Journal of Analytical Chemistry》1992,344(7-8):360-361
Summary Human serum albumin (HSA) and complement were photographically assayed. The complement activated by the formed antigen-antibody complex causes the hemolysis of red blood cells. Leaked hemoglobins catalyze the chemiluminescent reaction of luminol and hydrogen peroxide (H2O2). The resulting emission was recorded on instant film. 相似文献
85.
Motoyama S Makiura R Sakata O Kitagawa H 《Journal of the American Chemical Society》2011,133(15):5640-5643
Layer-structured metal-organic framework (MOF) nanofilms (NAFS-2) consisting of 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin (H(2)TCPP) molecules and copper ion metal linkers were assembled on a gold or a silicon surface by applying a solution-based layer-by-layer growth technique coupled with the Langmuir-Blodgett method. Synchrotron X-ray diffraction measurements showed that NAFS-2 exhibits highly crystalline order in both the in-plane and out-of-plane orientations. Each MOF sheet (monolayer) adheres without pillaring units, and the nanofilm maintains its highly crystalline order above 200 °C. The results provide an excellent demonstration of how to exercise in a facile way fine control of the assembly of molecule-based hybrid objects and their thermal stability, which is a key issue for the future use of MOFs in potential applications in nanodevices. 相似文献
86.
According to the concept of active sites, the activity of heterogeneous catalysts correlates with the number of available catalytic sites and the binding affinity of the substrates. Herein, we report a single-molecule, single-particle fluorescence approach to elucidate the inherent photocatalytic activity of exposed surfaces of anatase TiO(2), a promising photocatalyst, using redox-responsive fluorogenic dyes. A single-molecule imaging and kinetic analysis of the fluorescence from the products shows that reaction sites for the effective reduction of the probe molecules are preferentially located on the {101} facets of the crystal rather than the {001} facets with a higher surface energy. This surprising discrepancy can be explained in terms of face-specific electron-trapping probability. In situ observation of the catalytic events occurring at the solid/solution interfaces reveals the hidden role of the crystal facets in chemical reactions and their impact on the efficiency and selectivity of heterogeneous (photo)catalysts. 相似文献
87.
Prof. Dr. Shintaro Ishida Takuroh Hatakeyama Takuya Nomura Maiko Matsumoto Dr. Kimio Yoshimura Prof. Dr. Soichiro Kyushin Prof. Dr. Takeaki Iwamoto 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(68):15811-15815
The catalyst-free hydrosilylation of CO2 under mild conditions remains limited. Herein, we report the synthesis, characterization, and reactivity of 5,10,15,20-tetraphenylporphyrinato(dihydrido)silicon(IV) ( 1 ) as a six-coordinate silicon dihydride. The Si-H moiety of 1 reacts with polar double bonds and CO2 in the absence of a catalyst to afford hydrosilylated products. Combining the hydrosilylation with subsequent transformation furnishes formic acid from CO2. Computational studies indicate that the hydride-donor properties of 1 are exceptionally high for a neutral silicon hydride, and that the direct hydride transfer from silicon to carbon is a pivotal step in the hydrosilylation of CO2 with 1 . 相似文献
88.
Di-uracil substituted cyclen derivatives were prepared by the reaction of cyclen with 6-chloro-1-methyluracil or 6-chloro-1,3-dimethyluracil. The reaction of cyclam with 6-chloro-1,3-dimethyluracil gave a similar di-uracil substituted cyclam. The 1,7-di-uracil substituted cyclen was converted to the tricyclic guanidinium salt and acylurea upon heating in DMSO in the presence of weak acid. The 1,8-di-uracil substituted cyclam gave a tricyclic dihydroimidazolium salt under the same conditions. These reactions can be explained by an intramolecular uracil ring-breaking reaction mechanism. 相似文献
89.
90.
Yoshimoto S Tsutsumi E Honda Y Murata Y Murata M Komatsu K Ito O Itaya K 《Angewandte Chemie (International ed. in English)》2004,43(23):3044-3047