[en] Within the past few years, angle-resolved photoemission from adsorbate core levels has been experimentally investigated in a few laboratories as a new tool for determining surface atomic geometries. This type of measurement is of interest because the initial state is very simple, the emitting site is well defined, and essentially all anisotropy is produced by final-state photoelectron diffraction. Both variable-energy synchrotron radiation up to about 100 eV and standard soft X-ray sources at 1.5 keV have been used for excitation. In studies of various adsorbates (including atomic Na, Se, Te and O, and molecular CO) on transition-metal surfaces (Ni and Cu), several types of anisotropy useful for deriving structural information have been noted. These involve both polar- and azimuthal-angle scans of electron emission direction at constant hν, as well as scans of hν for a fixed normal emission direction. At lower energies, a full multiple-scattering theoretical analysis appears to be necessary whereas at higher XPS energies, a single-scattering approach has met with some success. Work to date will be briefly reviewed, and the future of the method will be discussed, particularly with reference to the involvement of synchrotron radiation. (orig.)

[en] X-ray computed tomography technique was used to observe microstructure formation during freeze-drying. A specially designed vacuum freeze-drying stage was equipped at the X-ray CT stage, and the frozen and dried microstructures of dextrin solutions were successfully observed. It was confirmed that the many parts of the pore microstructures formed as a replica of the original ice microstructures, whereas some parts formed as a consequence of the dehydration dependent on the relaxation level of the glassy phases, suggesting that the post-freezing annealing is advantageous for avoiding quality loss that relates to the structural deformation of glassy matters. (Author)

[en] Atomic photoionization subshell cross-sections and asymmetry parameters necessary for determining the differential cross-sections of randomly-oriented atoms have been calculated within the one-electron, central-potential model and the dipole approximation for all subshells of C, O, Al, Si, S, Ni, Cu, Ga, Ge, As, Se, In, Sb, Cs, Ba, Ce, Ta, W, Pt, Au, and Pb for a photon energy range from 20 to 1500 eV, and the relevant Cooper minima located to within 10 eV. These values are tabulated for general use, together with the associated radial matrix elements and phase shifts. Differential photoionization cross-sections for fixed-orientation s-, p- and d-orbitals have also been derived within the same model for a completely general experimental geometry, and closed-form expressions depending on radial matrix elements and phase shifts are given. For the special geometry of a polarized excitation source with polarization parallel to the electron emission direction, it is further shown that such oriented-atom cross-sections are exactly proportional to the probability distribution of the initial orbital, a result equivalent to that derived by using a plane-wave final-state approximation. However, detailed numerical calculations of cross-sections for oriented Cu 3d and O 2p orbitals in various general geometries and at various energies exhibit significant differences in comparison to plane-wave cross-sections. By contrast, certain prior angular-resolved X-ray photoemission studies of single-crystal valence bands are found to have been carried out in an experimental geometry that fortuitously gave cross-sections close to the plane-wave predictions. (orig.)

No abstract available

[en] The development of two processes for fabricating superconductors, to be used for the study of basic problems related to forced cooling by supercritical helium, is reported. The fabrication, specifications and characteristics of both the strip-tubing and the multi-filament cabling types of hollow superconductors are given. Both processes are feasible for manufacturing long conductors of various sizes without large machinery such as mechanical or hydrostatic extrders. (U.K.)

No abstract available

[en] Welding technology between 9Cr-ODS martensitic cladding and end-plugs has been developed by means of the pressurized resistance welding (PRW) method under solid state condition. The method is based on electrical resistance heating of the components while maintaining a continuous force sufficient to forge weld without melting. The appropriate conditions, e.g., electric current, voltage and contact force, were selected. For the PRW welded specimens, the tensile, internal burst and creep rupture tests were conducted and its integrity was confirmed. In addition, a non-destructive ultrasonic inspection method has been developed to assure the integrity of the weld between cladding and end-plug. The PRW was conducted to fabricate the ODS fuel pins in a JNC-Russia collaboration work, and the integrity accomplishment of the welded parts was verified through dimensional and leak testing, mechanical testing and micrographic examination

[en] Plasma levels of 2-hydroxyestradiol (2-OHE₂) were measured using a new RIA procedure. Values were below the detection limit of the assay (<10 pg/ml), except in the third trimester of pregnancy, when they rose to approximately 15 pg/ml. The infusion of 130 μg/h purified 2-OHE₂ elevated its plasma concentration to 155 pg/ml, consistent with a plasma MCR (MCR/sub p) of approximately 20,000 liters/day. The infusion of [³H]2-OHE₂ to equilibrium and chromatographic separation of the extracted plasma metabolites yielded an MCR/sub p/ of about 13,000 liters/day; the major plasma metabolite comigrated with 2-methoxyestradiol, and [³H]delta-methoxyestrone was also formed. The MCR/sub p/ of 2-OHE₂ is approximately half that of 2-hydroxyestrone (2-OHE)₁, but much higher than those of other steroids. As is true for 2-OHE₁ the clearance of 2-OHE₂ must occur primarily in the blood compartment. Together, the measured MCR/sub p/ values and estrogen receptor affinities of 2-OHE₂ and 2-OHE₁ predict a relative potency for effects upon gonadotropin secretion which is close to that observed in vivo

No abstract available

No abstract available