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141.
Takahashi M Kawamura A Kato N Nishi T Hamachi I Ohkanda J 《Angewandte Chemie (International ed. in English)》2012,51(2):509-512
Fluorescent combination: Cell-penetrating probes derived from the diterpene fusicoccin can form ternary complexes with 14-3-3 proteins and phosphopeptide ligands, whereupon the probes site-specifically attach a fluorescent tag onto the surface of the 14-3-3 proteins. 相似文献
142.
Uchiyama T Miyoki S Telada S Yamamoto K Ohashi M Agatsuma K Arai K Fujimoto MK Haruyama T Kawamura S Miyakawa O Ohishi N Saito T Shintomi T Suzuki T Takahashi R Tatsumi D 《Physical review letters》2012,108(14):141101
The thermal fluctuation of mirror surfaces is the fundamental limitation for interferometric gravitational wave (GW) detectors. Here, we experimentally demonstrate for the first time a reduction in a mirror's thermal fluctuation in a GW detector with sapphire mirrors from the Cryogenic Laser Interferometer Observatory at 17 and 18 K. The detector sensitivity, which was limited by the mirror's thermal fluctuation at room temperature, was improved in the frequency range of 90 to 240 Hz by cooling the mirrors. The improved sensitivity reached a maximum of 2.2×10(-19) m/√Hz at 165 Hz. 相似文献
143.
Suzuki M Kawamura N Miyagawa H Garitaonandia JS Yamamoto Y Hori H 《Physical review letters》2012,108(4):047201
We show that bulk gold (Au) exhibits temperature-independent paramagnetism in an external magnetic field by x-ray magnetic circular dichroism spectroscopy at the Au L(2) and L(3) edges. Using the sum-rule analysis, we obtained a magnetic moment of 1.3 × 10(-4) μB/atom in an external magnetic field of 10 T and a paramagnetic susceptibility of 8.9 × 10(-6) for the 5d orbit. The induced paramagnetism in bulk Au is characterized by a large (≈ 30%) orbital contribution. This orbital component was retained even when Au atoms formed nanoparticles, playing an important role in stabilizing the spontaneous spin polarization in the Au nanoparticles. 相似文献
144.
Yohsuke Satoh Takuya Yamada Yuto Onozaki Dai Kawamura Ichiro Hayakawa Hideo Kigoshi 《Tetrahedron letters》2012,53(11):1393-1396
Synthesis of the macrolactone part of biselides A (1) and B (2), marine cytotoxic polyketides, was achieved by using regioselective allylic oxidation as a key step. 相似文献
145.
Zone diagrams are a variation on the classical concept of Voronoi diagrams. Given n sites in a metric space that compete for territory, the zone diagram is an equilibrium state in the competition. Formally it is defined as a fixed point of a certain “dominance” map. Asano, Matou?ek, and Tokuyama proved the existence and uniqueness of a zone diagram for point sites in the Euclidean plane, and Reem and Reich showed existence for two arbitrary sites in an arbitrary metric space. We establish existence and uniqueness for n disjoint compact sites in a Euclidean space of arbitrary (finite) dimension, and more generally, in a finite-dimensional normed space with a smooth and rotund norm. The proof is considerably simpler than that of Asano et?al. We also provide an example of non-uniqueness for a norm that is rotund but not smooth. Finally, we prove existence and uniqueness for two point sites in the plane with a smooth (but not necessarily rotund) norm. 相似文献
146.
The separation of potassium and sodium ions from their mixture was performed by electrodialyzing a mixed solution of potassium
chloride and sodium chloride in the presence of 18-crown-6 using a commercial cation-exchange membrane. After 18-crown-6 had
been impregnated in the membrane, the mixed solution containing 18-crown-6 was electrodialyzed as the desalting-side solution.
The permeation of potassium ions through the membrane decreased remarkably and the electrical resistance of the membrane increased
during electrodialysis with increasing concentration of 18-crown-6 in the solution. Because potassium ions form a more stable
complex with 18-crown-6 than sodium ions and because the complex permeated through the membrane with difficulty, sodium ions
are thought to selectively permeate through the membrane. The current efficiency in electrodialysis was greater than 97.0%.
Received: 1 June 1999/Accepted in revised form: 13 August 1999 相似文献
147.
H. Kawamura R. M. Parr H. S. Dang W. Tian R. M. Barnes G. V. Iyengar 《Journal of Radioanalytical and Nuclear Chemistry》2000,245(1):123-126
Analytical quality assurance procedures adopted for use in the IAEA Co-ordinated Research Project on Ingestion and Organ Content of Trace Elements of Importance in Radiological Protection are designed to ensure comparability of the analytical results for Cs, I, Sr, Th, U and other elements in human tissues and diets collected and analysed in nine participating countries. The main analytical techniques are NAA and ICP-MS. For sample preparation, all participants are using identical food blenders which have been centrally supplied after testing for contamination. For quality control of the analyses, six NIST SRMs covering a range of matrices with certified and reference values for the elements of interest have been distributed. A new Japanese reference diet material has also been developed. These quality assurance procedures are summarized here and new data are presented for Cs, I, Sr, Th and U in the NIST SRMs. 相似文献
148.
149.
150.
E. Arakawa N. Ishimatsu N. Kawamura F. Itoh A. Ochiai H. Maruyama O. Shimomura 《Journal of Physics and Chemistry of Solids》2004,65(12):2089-2092
An experimental system for X-ray magnetic diffraction (XMD) under extreme conditions was constructed on the beamline BL39XU at SPring-8. This system aims at studying magnetic properties of ferromagnets through the measurements of magnetic form factors under the conditions of low temperature (5 K), high magnetic field (6 T) and high pressure (10 GPa). This system consists of a superconducting magnet (SCM), a diamond anvil cell (DAC), a two-axis manipulator for the DAC, a five-axis goniometer for the SCM, and an X-ray polarizer with a phase plate. Details of this system are presented. Experimental results on uranium telluride are shown as a performance test with this instrumentation. 相似文献