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An effect of nuclear elastic scattering (NES) on the energy transfer to plasma ions and electrons during (a) neutral beam injection (NBI) and (b) α-particle heating operations is examined on the basis of the Boltzmann-Fokker-Planck (BFP) equation for a beam ion and an α-particle in deuterium-tritium thermonuclear plasmas. The BFP calculations show that the enhancement in the fraction of the NBI heating power deposited to ions due to NES becomes appreciable when the beam energy is larger than 1MeV. How the NES effect is influenced by the plasma condition is discussed.

In D–T fusion plasma seeded with a small amount of 6 Li, monochromatic 0.429-, 0.478- and 0.981-MeV γ rays are produced in the 6 Li+D and 6 Li+T nuclear reactions. In the present paper we investiga...

The molecular structures of two [2.2]paracyclophanes containing a 7,7,8,8-tetracyanoquinodimethan (TCNQ) moiety as an electron acceptor have been determined by means of X-ray diffraction. The electron-donating moieties in these cyclopahnes are benzene (TCNQ-X) and p-dimethoxybenzene (TCNQ-X (OMe)2) rings. TCNQ-X crystallizes in a triclinic space group P\bar1 with two molecules per unit cell; a=9.772(2), b=18.477(4), c=6.569(1) A, α=90.38(2), β=107.92(2), γ=100.32(2)°. The crystals of TCNQ-X(OMe)2 belong to the orthorhombic system; space group Fdd2; a=25.618(3), b=31.895(5), c=9.808(1) A, Z=16. Both structures were solved by the direct method and refined by the block-diagonal least-squares procedure to R=0.088 (TCNQ-X) and 0.109 (TCNQ-X(OMe)2) for 3141 and 1695 non-zero rehections. In the two structures determined, the [2.2] paracyclophane skeleton has the usual structure; the benzene ring and six-membered ring of the TCNQ moiety have a boat form, and two C(CN)2 portions in the TCNQ moiety are bent down fr...

The molecular structure of the sole photocycloaddition product of α-naphthonitrile with phenyl vinyl ether, C19H15ON was determined by means of X-ray diffraction. The crystals are monoclinic, space group P21/c, unit-cell dimensions are a=11.563(2), b=9.826(1), c=14.324(2) A, β=113.46(1)°, Z=4. The structure was solved by the direct method, the final R value being 0,042 for 2022 non-zero reflections. The molecule has an endo-configuration, and the cyclobutane ring is puckered.

Under tritium production method using a high-temperature gas-cooled reactor loaded Li compound, Li compound has to be coated by ceramic materials in order to suppress the spreading of tritium to the whole reactor. Pyrolytic carbon (PyC) is a candidate of the coating material because of its high resistance for gas permeation. In this study, hydrogen permeation experiments using a PyC-coated isotropic graphite tube were conducted and hydrogen diffusivity, solubility and permeability were evaluated. Tritium permeation behavior through PyC-coated Li compound particles was simulated by using obtained data. Hydrogen permeation flux through PyC in a steady state is proportional to the hydrogen pressure and is larger than that through Al 2 O 3 which is also candidate coating material. However, total tritium leak within the supposed reactor operation period through the PyC-coated Li compound particles is lower than that through the Al 2 O 3 -coated ones because the hydrogen absorption capacity in PyC is considerably larger than that in Al 2 O 3 .