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This paper investigated dynamic responses of steel monorail bridges incorporating train-bridge interaction under strong earthquakes. Two types of steel monorail bridges were considered in the study: a conventional type with steel track-girder; an advanced type with composite track-girder and simplified lateral bracing system. During strong earthquakes, monorail train was assumed standing on the track-girder of monorail bridges. Observations through the analytical study showed that considering the monorail train as additional mass rather than a dynamic system in numerical modeling overestimated effect of the train load on seismic performance of monorail bridges. Earlier plastic deformations at the end bracing of the girder system absorbed seismic energy and reduced the stress at the pier base.

Fullerene field-effect transistors (FETs) were fabricated with thin films of C_<84>, which showedn-channel normally-on depletion-type FET characteristics. The C_<84> FET device exhibited the highest mobility, μ, of 2.1×10^<－3> cm^2 V^<－1> s^<－1> among normally-on fullerene FETs. The carrier transport of this FET device can be interpreted as thermally activated hopping transport. Carrier type (n-channel) and transport mechanism (hopping) reflect the electronic properties of the C_<84> molecule.

Dy@C_<82> and Dy@C_<60> adsorbed on Si (111)-(7×7) surface are investigated by scanning tunneling microscopy (STM) at 295 K. The Dy@C_<82> molecules in the first layer are adsorbed on the Si (111)-(7×7) surface without formation of islands and nucleation, and the internal structure of the Dy@C_<82> molecule is first observed on the surface at 295 K. The average heights of the Dy@C_82 molecules in the first and second layers are estimated to be 7.2 and 10.8 Å, respectively, by STM. These results suggest strong interactions between the Si atoms and the Dy@C_<82> molecules in the first layer. The STM image reveals that the Dy@C_<60> molecule is nearly spherical, showing that the metal endohedral C_<60> possesses a cage-form structure., identifier:10980121, identifier:https://dspace.jaist.ac.jp/dspace/handle/10119/3366

Dy@C_<82> and Dy@C_<60> adsorbed on Si (111)-(7×7) surface are investigated by scanning tunneling microscopy (STM) at 295 K. The Dy@C_<82> molecules in the first layer are adsorbed on the Si (111)-(7×7) surface without formation of islands and nucleation, and the internal structure of the Dy@C_<82> molecule is first observed on the surface at 295 K. The average heights of the Dy@C_82 molecules in the first and second layers are estimated to be 7.2 and 10.8 Å, respectively, by STM. These results suggest strong interactions between the Si atoms and the Dy@C_<82> molecules in the first layer. The STM image reveals that the Dy@C_<60> molecule is nearly spherical, showing that the metal endohedral C_<60> possesses a cage-form structure.

The crystal structure of Dy@C_<82> isomer I at 298 K has been determined by Rietveld refinement for x-ray powder diffraction with synchrotron radiation. Isomer I shows a simple cubic structure (sc: Pa3^^-) with a lattice constant a of 15.78(1) Å. The C_2 axis of a C_2v-C_<82> cage aligns along the［111］direction of this crystal lattice. The C_<82> cage is orientationally disordered to satisfy a 3^^- symmetry along ［111］, which is requested in this space group. The large thermal parameter for the Dy atom estimated from the x-ray diffraction probably reflects a large disorder caused by a floating motion of the Dy atom inside the C_<82> cage as well as a ratchet-type motion of the Dy@C_<82> molecule. The electronic transport of thin film of Dy@C_<82> shows a semiconducting behavior. The energy gap E_g is estimated to be 0.2 eV. Further, the variation of valence from Dy^ <3+> to Dy^<2+> is found by metal doping into the Dy@C_<82> crystals., identifier:10980121, identifier:https://dspace.jaist.ac.jp/dspace/handle/10119/3363

N-channel field effect transistors (FETs) were fabricated with thin films of C_<60> and Dy@C_<82>. A typical enhancement-type FET property was observed in C_<60> FET above 220 K. The mobility of C_<60> FET increased with increasing temperature. This fact suggests hopping transport as the conduction mechanism, with the activation energy of 0.29 eV. The Dy@C_<82> FET was found to be a normally-on type FET, which has a property different from that for C_<60> and C_<70> FETs. A complementary metal oxide semiconductor (CMOS) logic gate circuit was first fabricated with C_<60> and pentacene thin-film FETs., identifier:https://dspace.jaist.ac.jp/dspace/handle/10119/4938

The crystal structure of Dy@C_<82> isomer I at 298 K has been determined by Rietveld refinement for x-ray powder diffraction with synchrotron radiation. Isomer I shows a simple cubic structure (sc: Pa3^^-) with a lattice constant a of 15.78(1) Å. The C_2 axis of a C_2v-C_<82> cage aligns along the［111］direction of this crystal lattice. The C_<82> cage is orientationally disordered to satisfy a 3^^- symmetry along ［111］, which is requested in this space group. The large thermal parameter for the Dy atom estimated from the x-ray diffraction probably reflects a large disorder caused by a floating motion of the Dy atom inside the C_<82> cage as well as a ratchet-type motion of the Dy@C_<82> molecule. The electronic transport of thin film of Dy@C_<82> shows a semiconducting behavior. The energy gap E_g is estimated to be 0.2 eV. Further, the variation of valence from Dy^ <3+> to Dy^<2+> is found by metal doping into the Dy@C_<82> crystals.

N-channel field effect transistors (FETs) were fabricated with thin films of C_<60> and Dy@C_<82>. A typical enhancement-type FET property was observed in C_<60> FET above 220 K. The mobility of C_<60> FET increased with increasing temperature. This fact suggests hopping transport as the conduction mechanism, with the activation energy of 0.29 eV. The Dy@C_<82> FET was found to be a normally-on type FET, which has a property different from that for C_<60> and C_<70> FETs. A complementary metal oxide semiconductor (CMOS) logic gate circuit was first fabricated with C_<60> and pentacene thin-film FETs.