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181.
R. Ukita A. Sugimoto T. Ekino 《Physica C: Superconductivity and its Applications》2011,471(21-22):622-624
We have investigated the iron-chalcogenide superconductor Fe(Se, Te) using a low-temperature scanning tunneling microscopy/spectroscopy (STM/STS) technique. STM topography at 4.9 K shows clear regular square arrangements of spots with the lattice spacing ~0.37 nm, from which what we observe are attributed to Se or Te atomic plane. In the topography, brighter and darker atomic spots are randomly distributed, which are most probably due to Te and Se atoms, respectively. For the FeTe compound, the topography exhibits clusters of the bright spots probably arising from separated iron atoms distributing over several Te lattice sites. The STS measurements clarify the existence of the large-size gap with 2Δ = 0.4–0.6 eV. 相似文献
182.
Effects of Motion, Implied Direction and Displacement of a Large-Visual-Stimulus on Postural Control
Effects of motion, implied direction in a static stimulus and displacement on postural control were examined independently.
In Experiment 1, rotation of a random-dot stimulus was presented. In Experiments 2 and 3, photographic slides of natural scenes
were used; participants closed their eyes during stimulus rotation to eliminate motion information. In Experiment 2, the stimulus
was presented upright initially, then presented again with a tilt. In Experiment 3, the order was reversed to separate the
effects of implied direction and displacement. Results showed that all information of motion, implied direction, and displacement
had some effect on postural control, although visual information of motion has been presumed to have a principal effect on
postural control. Results suggested that the effects of implied direction might reflect an immediate processing of information.
The effects of displacement and motion might reflect a continuous processing of information. 相似文献
183.
Takayuki Kato Kunihisa Sugimoto Mikio Yamasaki 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(11):1256-1258
The title compound, [Cu(C13H10N4O5)(H2O)], is an asymmetric and pentacoordinated square-pyramidal copper(II) complex, with a water molecule occupying an apical position. It consists of syn and anti isomers of the apical water molecule with respect to the metal-free carboxyl group on the equatorial ligand. The crystal structure of this complex is a rare example of conformational isomerization, in which the two isomers cocrystallize in a 1:3 ratio of syn to anti molecules in the same lattice. 相似文献
184.
185.
Inside Cover: Inhibition of Heme Uptake in Pseudomonas aeruginosa by its Hemophore (HasAp) Bound to Synthetic Metal Complexes (Angew. Chem. Int. Ed. 11/2014) 下载免费PDF全文
186.
187.
Shin Nakamura Yorihiko Tsunoda Ippei Nomoto Hirohiko Sato 《Hyperfine Interactions》2010,197(1-3):101-104
In order to investigate the electronic state, the local structure, and the magnetic structure of a new ion oxide Fe3B7O13(OH), we have applied 57Fe Mössbauer spectroscopy. The room-temperature values of isomer shift and quadrupole splitting are 1.16 mm/s and 3.21 mm/s, respectively, which indicate that the Fe ions are in high spin Fe2?+? state. The spectrum at 4.2 K is composed of a well-resolved hyperfine sextet with the hyperfine field of 3.6 T. In a trimer, each Fe2?+? magnetic moment is supposed to be directed from Fe2?+? to OH???. 相似文献
188.
The interaction of atomic H with Ag(1 1 1)/Si(1 1 1)7 × 7 surfaces was studied by thermal desorption (TD) spectroscopy and scanning tunneling microscopy (STM) at room temperature. TD spectroscopy revealed an intense peak from mono H–Si bonds, even though the Si surface was covered by the Ag atoms. This peak was not observed from Ag-coated SiO2/Si substrates. STM observation showed no clear change of the Ag surface morphology resulting from H exposure. All these results indicate that the atomic H adsorbs at neither the Ag surfaces nor Ag bulk sites, but at the Ag/Si interface by diffusing through the Ag film. 相似文献
189.
The effect of molecular crowding on the structure and stability of biomolecules has become a subject of increasing interest because it can clarify how biomolecules behave under cell-mimicking conditions. Here, we quantitatively analyzed the effects of molecular crowding on the thermodynamics of antiparallel G-quadruplex formation via Hoogsteen base pairs and of antiparallel hairpin-looped duplex (HP duplex) formation via Watson-Crick base pairs. The free energy change at 25 degrees C for G-quadruplex formation decreased from -3.5 to -5.5 kcal mol(-1) when the concentration of poly(ethylene glycol) 200 was increased from 0 to 40 wt %, whereas that of duplex formation increased from -9.8 to -6.9 kcal mol(-1). These results showed that the antiparallel G-quadruplex is stabilized under molecular crowding conditions, but that the HP duplex is destabilized. Moreover, plots of stability (ln K(obs)) of the DNA structures versus water activity (ln a(w)) demonstrated that the ln K(obs) for G-quadruplex formation decreased linearly as the ln a(w) increased, whereas that for duplex formation increased linearly with the increase in ln a(w), suggesting that the slope approximately equals the number of water molecules released or taken up during the formation of these structures. Thus, molecular crowding affects the thermodynamics of DNA structure formation by altering the hydration of the DNA. The stabilization of the DNA structures with Hoogsteen base pairs and destabilization of DNA structures with Watson-Crick base pairs under molecular crowding conditions lead to structural polymorphism of DNA sequences regulated by the state of hydration. 相似文献
190.
Hayashi T Murata D Makino M Sugimoto H Matsuo T Sato H Shiro Y Hisaeda Y 《Inorganic chemistry》2006,45(26):10530-10536
The incorporation of an artificially created metal complex into an apomyoglobin is one of the attractive methods in a series of hemoprotein modifications. Single crystals of sperm whale myoglobin reconstituted with 13,16-dicarboxyethyl-2,7-diethyl-3,6,12,17-tetramethylporphycenatoiron(III) were obtained in the imidazole buffer, and the 3D structure with a 2.25-A resolution indicates that the iron porphycene, a structural isomer of hemin, is located in the normal position of the heme pocket. Furthermore, it was found that the reconstituted myoglobin catalyzed the H2O2-dependent oxidations of substrates such as guaiacol, thioanisole, and styrene. At pH 7.0 and 20 degrees C, the initial rate of the guaiacol oxidation is 11-fold faster than that observed for the native myoglobin. Moreover, the stopped-flow analysis of the reaction of the reconstituted protein with H2O2 suggested the formation of two reaction intermediates, compounds II- and III-like species, in the absence of a substrate. It is a rare example that compound III is formed via compound II in myoglobin chemistry. The enhancement of the peroxidase activity and the formation of the stable compound III in myoglobin with iron porphycene mainly arise from the strong coordination of the Fe-His93 bond. 相似文献