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A 89m-long spiral trench in 4” Si wafer is fabricated as the coil mold for the compact superconducting magnetic energy storage. Seven parallel 3-stepped micro-trench can reduce the disconnection risk caused by defects being the safety each other.

The influence of segregated sulfur on palladium permeability was investigated using deuterium permeation through palladium membrane, which was pretreated by annealing in vacuum and/or in air. It has been found that the palladium membrane is almost impermeable after vacuum annealing, while it is permeable after air annealing. A combination of vacuum annealing of a Pd membrane followed by annealing in air leads to better and more stable D2 permeation because S has been depleted from the Pd bulk. In fact, cleaning S from Pd in spell out (UHV) normally proceeds via cycles of high T annealing to drive S to the surface, followed by burning off the S as SO2 by heating in an O2 environment. The results in this study well demonstrate the influence of sulfur on the deuterium-permeation rate and on the behavior of sulfur segregation from Pd bulk to the surface.

1H- and 3H-Cyclopent[a]azulenes having an electron withdrawing group, such as a methoxycarbonyl or a cyano group, at the 9-position were synthesized from their dihydro compounds by means of bromination with NBS and succeeding dehydrobromination by refluxing in chloroform. Base-catalyzed condensation of these cyclopent[a]azulenes with carbonyl compounds afforded 1-methylene-1H- and 3-methylene-3H-cyclopent[a]azulene derivatives having an electron withdrawing group at the 9-position. The physical properties of these methylenecyclopent[a]azulenes are also discussed.

1H- and 3H-Cyclopent[a]azulenes having an electron withdrawing group, such as a methoxycarbonyl or a cyano group, at the 9-position were synthesized from their dihydro compounds by means of bromination with NBS and succeeding dehydrobromination by refluxing in chloroform. Base-catalyzed condensation of these cyclopent[a]azulenes with carbonyl compounds afforded 1-methylene-1H- and 3-methylene-3H-cyclopent[a]azulene derivatives having an electron withdrawing group at the 9-position. The physical properties of these methylenecyclopent[a]azulenes are also discussed.

The effects of the oxygen deficiency on the electrical and magnetic properties of Sr 2 VO 4− δ were investigated. Single-phase samples of polycrystalline Sr 2 VO 4− δ with δ =0.18, 0.29 and 0.38 were synthesized by the solid state reaction in flowing hydrogen atmosphere. The crystal structure was determined by Rietveld analysis of X-ray diffraction data. All the samples were tetragonal at 298 K. With increase of δ, the lattice constant ‘a’ decreased and the lattice constant ‘c’ increased. Electrical resistivity measurements showed that all the samples were semiconductive with resistivity of about 1Ωcm at 298 K. Magnetic measurements showed that the magnetic properties of Sr 2 VO 4− δ system were strongly dependent on the oxygen deficiency δ. It was suggested that the non oxygen-deficient compound Sr 2 VO 4 ( δ =0) had no magnetic long-range order. As δ was increased, spin-glass-like behavior became evident at low temperatures and was overlapped by a long-range magnetic order with a transition temperature of ∼ 35 K for δ ≧ ∼ 0.2 . It was suggested that the long-range magnetic order was a canted antiferromagnetism with a small net magnetization.

A new tricyclic π-conjugated system, cyclopent[a]azulen-3(H)-one, was prepared by flash vacuum pyrolysis on the final step. All proton signals of this molecule were observed at higher magnetic resonance field than expected in terms of induced paramagnetic ring current in the periphery of this molecule.

A layered perovskite compound Sr3V2O7.01 was synthesized by heating mixtures of the constituent oxides at 1110°C in flowing hydrogen atmosphere. Rietveld analysis based on powder X-ray diffraction data shows that the compound has a tetragonal structure (I4/mmm) with a = 3.8331(7) A and c = 20.2459(6) A . The resistivity of the compound is 4.8 mΩ· cm at room temperature (300 K) and decreases with decreasing temperature down to 2 K. The magnetic susceptibility can be represented by a summation of temperature-independent and Curie-Weiss terms. The effective number of Bohr magnetons per vanadium atom is 0.37, which is considerably smaller than the free-ion value of 1.73 for V4+.

A new compound Sr4V3O9.60±0.01 has been synthesized by solid state reaction in flowing hydrogen atmosphere. Rietveld analysis based on X-ray diffraction data shows that it has a tetragonal structure (I4/mmm) with a = 3.8457(1) A and c = 27.9017(3) A . The resistivity of the compound is 1.4 mΩ · cm at room temperature (300 K) and decreases with decreasing temperature down to about 100 K followed by a slight increase with a further decrease of temperature. The magnetic susceptibility can be represented by a summation of temperature-independent and Curie-Weiss terms. The effective number of Bohr magnetons per vanadium atom is 0.37, which is considerably smaller than the free-ion values of 2.83 for V3+ and 1.73 for V4+. These results suggest that electron-electron interactions among the narrow π∗ band (t2g symmetry) electrons are important in this compound.

It is generally believed that the superconducting transition temperature ( T c ) of YBa 2 Cu 3 O x constantly increases as x increases up to 7. On the contrary, measurements of electric properties for epitaxially-grown thin films show that the T c is reduced near x =7. This reduction in T c reminds one of the property of La 2− y Sr y CuO 4 for high hole concentration, that is, the T c is reduced by excess hole doping. This over-hole-doping state may be an intrinsic feature of YBa 2 Cu 3 O ≈7 .

A new tricyclic π-conjugated system, cyclopent[a]azulen-3(H)-one, was prepared by flash vacuum pyrolysis on the final step. All proton signals of this molecule were observed at higher magnetic resonance field than expected in terms of induced paramagnetic ring current in the periphery of this molecule.

The behaviour of deuterium implanted in Al was studied by the D(3He,p)4He and the D(d,p)T nuclear reactions. Changes of the depth profiles on the deuterium after heat treatments indicated that the implanted deuterium was trapped by the defect produced during the deuterium implantation and the release probability of the trapped deuterium increased as the specimen temperature was raised. Assuming a thermal equilibrium locally in the region of high defect concentration, the trapping energy of deuterium in Al was determined to be 0.12 eV. Since the release probability for the single crystal was considerably larger than that for the polycrystal specimens, the deuterium was considered to be strongly trapped in the grain boundaries. Distributions of displaced Al atoms and the recovery of the lattice damage by annealing were measured by the channelling technique.

Crotonothioamide, sorbothioamide, and cinnamothioamide undergo a threo selective aldol condensation via their enolates generated by a Michael addition of organometallics.