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121.
Yuta Takano 《Fullerenes, Nanotubes and Carbon Nanostructures》2014,22(1-3):243-249
Chemical syntheses and intramolecular electron transferring behaviors in the electron donor/acceptor conjugates based on endohedral metallofullerenes, La2@C80 and La@C82, are overviewed. A study on the photo-induced excited states of a La2@C80 derivative connected with an electron donor revealed the formation of a distinct radical ion pair state. A La@C82 derivative linked with an electron donor demonstrated an unprecedented ion/anion pair state, and La2@C80 tethered with an acceptor showed a fullerene donor system, in which the fullerene acts as an electron donor. Using endohedral lanthanide metallofullerenes for intramolecular electron transferring systems opens a new door for developing novel molecular materials. 相似文献
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123.
Ikuya Kinefuchi Yusuke Kotsubo Kenichi Osuka Yuta Yoshimoto Nobuya Miyoshi Shu Takagi Yoichiro Matsumoto 《Microfluidics and nanofluidics》2017,21(2):15
The scattering dynamics of water molecules on solid surfaces was investigated using the molecular beam technique. In contrast to the experiments previously reported in the literature, the range of incident energy was chosen to cover the typical kinetic energies of gas molecules in equilibrium at room temperature (35–130 meV). Even in such a narrow energy range, the angular distribution of scattered molecules is heavily affected by the incident energy, exhibiting both a nearly cosine distribution and a lobular distribution, which has a clear peak close to the specular direction. Interestingly, the tangential momentum accommodation coefficients (TMACs) estimated from the scattering experiments show opposite energy dependences on graphite (0001) and silicon (100) surfaces. As the incident energy increases, the TMAC decreases on the graphite surface, whereas it increases on the silicon surface. These trends can be attributed to the relatively large adsorption energy of water molecules on these surfaces and the atomic-scale surface corrugation, although a rigorous understanding requires further analysis by molecular dynamics simulations. Our findings suggest the need for an elaborate slip-flow model that takes account of the incident energy effect to accurately analyze water vapor flow in micro/nanostructures, which is ubiquitous in nature and engineering applications. 相似文献
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125.
Fish test for endocrine-disruption and estimation of water quality of Japanese rivers 总被引:11,自引:0,他引:11
The LC50 values (72 h) of 17beta-estradiol (E2), p-nonylphenol (NP) and bis-phenol-A (BPA) to adult male and female medaka were 3.5 and 3.5, 0.85 and 0.87, and 6.8 and 8.3 mg L(-1), respectively; the LC50 values to embryos were 0.46, 0.13 and 5.1 mg L(-1), respectively. The IC50 values for inhibition to egg hatching were 0.47, 0.85 and 9.0 mg L(-1), respectively. These values were much higher than concentrations detected in river water in Japan and the chemicals were considered to have no lethal effect on the fish in an aquatic environment. Mature male medaka was continuously exposed to 0.005, 0.05 or 1.0 microg L(-1) of E2, or to 0.1, 10 or 100 microg L(-1) of NP or BPA. Female specific proteins (FSP) were induced in the blood of male medaka that were exposed for 5 weeks to E2 higher than 0.005 microg L(-1), NP higher than 0.1 microg L(-1), or BPA higher than 10 microg L(-1). Based on these FSP inducible concentrations and reported concentrations of E2, NP and BPA in Japanese river water, some river water contaminated by E2 or NP could be estimated as the FSP inducible in male medaka. 相似文献
126.
Yuta Matsushima Tsutomu Yamazaki Kazuyuki Maeda Tatsuo Noma Takeyuki Suzuki 《Journal of the American Ceramic Society》2006,89(3):799-804
Plasma oxidation of a titanium electrode above liquid water was investigated to reveal the interaction between metallic titanium and plasma above liquid water. Dc-plasma was generated between the titanium and water electrodes. When the titanium electrode was set as anodal, a thick rutile layer was formed on the surface. We had reported previously that the layer showed the preferred orientation along 〈110〉normal to the surface. The degree of the preferred orientation showed a maximum of 0.8 at the electrode temperature of 1073 K. When the titanium electrode was set as cathodal, a plume was generated with the temperature rise because of the bombarding effect of cationic species in the plasma. The collected particles were spherical and were identified as anatase with a small amount of rutile. Optical emission spectroscopy suggested that an oxide layer (TiO2 ) firstly formed on the Ti cathode surface, and then vaporization took place with the temperature rise. The spherical anatase particles were formed from the TiO2 vapor through the rapid cooling. 相似文献
127.
Satoshi Murakawa Yuichiro Wada Yuta Tamura Masamichi Saitoh Yuki Aoki Ryuji Nomura Yuichi Okuda 《Journal of Low Temperature Physics》2008,150(3-4):154-159
We measured the complex transverse acoustic impedance of superfluid 3He in the B phase by coating a surface with 4He to study the boundary condition dependence of the surface bound states. Observed features in the temperature dependence
were similar to those without 4He coating. However, temperatures showing singularities became higher and variations in the dependence became smaller. The
small variations indicated that a specular surface was realized by the 4He coating. Increase in the singularity temperature indicated that the bandwidth of the surface Andreev bound states became
broader by the coating.
相似文献
128.
Ca3Co4O9 ceramic powders were synthesized by the polymerized complex (PC) method and consolidated by the hydrothermal hot-pressing
(HHP) technique. Observation by scanning electron microscope indicated that the form of powders by the PC process was fine
and flaky. The density of the sintered body increased with an increase of the operating temperature and pressure during the
HHP process. The electrical resistivity was greatly reduced with an increase of the operating pressure, but the thermal conductivity
is prone to increase with an increase of the operating temperature and pressure. The Seebeck coefficient was hardly affected
by the HHP condition. As a result, the sample treated by the HHP process under the condition of 573 K, 200 MPa, and 1 h showed
a maximum ZT of about 0.29 at 1,073 K. 相似文献
129.
130.