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  • 1
    Electronic Resource
    Electronic Resource
    Emission life and surface analysis of barium-impregnated thermionic cathodes (1993)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 74 (1993), S. 6482-6487 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Emission life of small Ba-impregnated thermionic cathodes suitable for use in TV tubes is investigated systematically. Cathodes are covered with an Os layer to enhance the emissivity. They have an unusual emission life in that the emission current decreases gradually with time and then drops abruptly. The early gradual decrease in emission at high cathode temperatures is caused by the phase change of the Os layer to OsW2. A linear relationship is found to exist between the logarithm of the lifetime and the reciprocal of the cathode temperature. This life end is believed to happen after the end of the reduction reaction between BaO and the porous W body and after ceasing replenishment of the low work function Ba+-O− monolayer on the metal surface. A formula for the emission lifetime is derived from the assumption that the rate determining step is the Ba diffusion inside the pellet. Emission lifetime τ is shown to be given by τ=Ad2 exp(E/kT), where A is a constant, d is the pellet thickness, and E is the activation energy of Ba diffusion. This relation is confirmed experimentally.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.355136
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  • 2
    Electronic Resource
    Electronic Resource
    Pressure-induced phase transition in solid hydrogen sulfide at 11 GPa (1991)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 95 (1991), S. 2036-2040 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The Raman spectra of hydrogen-bonded molecular solid H2S have been measured up to 23 GPa at 300 K in a gasketed diamond-anvil cell. In the orientationally disordered phase I between 0.47 and 11 GPa, the symmetric stretching mode ν1 shows a red-shift in frequency (dν1/dP=−10.1 cm−1/GPa ) and a dramatic broadening with pressure. At about 11 GPa, the antisymmetric stretching band ν3 appears at the higher-frequency side of ν1. Near this same pressure five low-frequency vibrational modes also appear and show pressure-sensitive features. These results indicate a pressure-induced phase transition near 11 GPa. This new solid phase, which persists to at least 23 GPa at 300 K, seems to be the same phase as previously found above 3.3 GPa at 25 K.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.461002
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  • 3
    Electronic Resource
    Electronic Resource
    High-pressure Raman study of solid deuterium sulfide up to 17 GPa (1992)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 97 (1992), S. 7137-7139 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: High-pressure Raman studies up to 17 GPa have been made on solid D2S at room temperature. Features of vibron and phonon modes indicate a pressure-induced phase transition near 10 GPa. In the orientationally disordered phase I between 0.5 and 10 GPa, the symmetric stretching mode ν1 shows a red-shift in frequency (dν1/dP=−6.0 cm−1/GPa). By comparing with recent studies of solid H2S, the deuterium isotope effects are investigated for vibrational properties and phase transitions of D2S under ultrahigh pressures.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.463538
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  • 4
    Electronic Resource
    Electronic Resource
    Temporal behavior of the electron density profile during limiter biasing in the HYBTOK-II tokamak (1994)
    [S.l.] : American Institute of Physics (AIP)
    Physics of Plasmas 1 (1994), S. 1089-1091 
    Details
    ISSN: 1089-7674
    Source: AIP Digital Archive
    Topics: Physics
    Notes: A rapid change in the detailed edge electron density profile during positively biased limiter experiment is obtained with high temporal resolution of ∼20 μs using a laser blowoff lithium beam probe technique in HYBTOK-II tokamak [IEEE Trans. Plasma Sci. PS-19, 885 (1991)]. The transient change in the electron density profile and the movement of the position where a steep density gradient is formed are experimentally observed. The temporal behavior of the electron density profile correlates well with reductions in the biasing current and Hα emission in the scrape-off layer, and the suppression of electrostatic fluctuations near the edge of the core region.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.870788
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  • 5
    Electronic Resource
    Electronic Resource
    Laser blow-off lithium beam probing with high temporal resolution for edge plasma diagnostics (1993)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 64 (1993), S. 2277-2284 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: Laser blow-off neutral lithium beam probing with high temporal resolution has been developed to measure edge electron density profiles in a plasma. A new electron density reconstruction method, taking account of the transport of a laser blow-off beam in the plasma, improves the accuracy of the density measurement. The use of a camera system with a gate function makes it possible for us to measure the density profile with a high temporal resolution of 10–50 μs. The optimum condition for shutter timing and period to observe the Li i emission profile is discussed from the viewpoints of the beam penetration into the plasma and the accuracy of measurement. A rapid temporal evolution of the edge electron density profile during limiter biasing in a small tokamak HYBTOK-II was successfully obtained by this system.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1143923
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  • 6
    Electronic Resource
    Electronic Resource
    Edge plasma density reconstruction for fast monoenergetic lithium beam probing (1993)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 64 (1993), S. 1699-1704 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: Two different electron density reconstruction methods for 8-keV neutral lithium beam probing have been developed for the Compact Helical System (CHS). Density dependences on emission and ionization processes are included by using effective rate coefficients obtained from the collisional radiative model. Since the two methods differ in the way the local beam density in the plasma is determined, the methods have different applicable electron densities. The beam attenuation is calculated by iteration from the electron density profile in method I. In method II, the beam remainder at the observation point z is determined by integrating the Li i emission intensity from z toward the position of emission tail-off. At the emission tail-off, the fast lithium beam is completely attenuated. Selecting an appropriate method enables us to obtain edge electron density profile well inside the last closed flux surface for various ranges of plasma densities (1012–5×1013 cm−3). The electron density profiles reconstructed by these two different methods are in good agreement with each other and are consistent with results from ruby laser Thomson scattering.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1143996
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  • 7
    Electronic Resource
    Electronic Resource
    (NH4)2Sx-treated InP(001) studied by high-resolution x-ray photoelectron spectroscopy (1994)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 76 (1994), S. 3059-3062 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The chemical state of sulfur on (NH4)2Sx-treated InP(001) surfaces has been studied by high-resolution x-ray photoelectron spectroscopy. We find three kinds of chemical states of sulfur (S2p3/2 lines at 161.2, 162.0, and 163.4 eV) on the sample treated at RT. It is suggested that they correspond to sulfur in phosphorus sites (in the second layer of the InP(001) surface), to sulfur bonded to indium on the first layer, and to elemental sulfur on sulfide, respectively. One (S2p3/2=162.0 eV) of them becomes predominant with long-time exposure to atmosphere at RT. Upon annealing the sample at 400 °C, the 163.4 eV line disappears, while the lines at 162.0 and 161.2 eV remain on the surface. A model of the treated surface is presented.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.357487
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  • 8
    Electronic Resource
    Electronic Resource
    Enhancement of human fibroblast growth and other dermatological effects induced by cell extract from heat-shocked blue green alga (Cyanobacteria) (2004)
    Oxford, UK : Blackwell Science Ltd
    International journal of cosmetic science 26 (2004), S. 0 
    Details
    ISSN: 1468-2494
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: It has been known that high amounts of ‘heat shock proteins (HSPs)’ are produced under heat and other environmental stresses in cells. Recently, it was reported that HSP could also be accumulated in some dermal cells to protect the cellular proteins from damage caused by ultraviolet radiation. Here, the authors have focused on thermophilic cyanobacteria and the heat shock treatment. Thermophilic cyanobacteria are known to thrive under extreme environmental conditions, and produce distinctively high amounts of HSP when exposed to higher temperatures. We tested cell extract from heat-shocked cyanobacterial cells on a number of skin-related biological activities and found it significantly effective. The cyanobacterial cells, originally collected from a spa as hot as 55 °C, were cultivated in the laboratory at 50 °C and broken by a freeze-fracture method. The extract thus obtained had a superoxide dismutase (SOD)-like activity and inhibited lipid peroxide formation. We found that the extract obtained from the heat-shocked (at 63 °C) cells showed a much stronger SOD-like activity, while the inhibitory effect on lipid peroxide formation remained almost the same. Furthermore, the SOD-like activity could withstand heat up to 70 °C for as long as 1 h. Most remarkably, supplementing this heat-shocked extract strongly promoted the proliferation of human dermal fibroblast culture. Extracts from the cells grown at a regular temperature (50 °C) did not promote the proliferation of the fibroblasts. The heat-shocked extract was fractionated by ultrafiltration for further analysis. A fraction (molecular weight: 10 000–30 000) has shown the strongest activity so far. These results indicate that the heat-shocked cyanobacterial extract with its increased amounts of HSPs is a promising potent ingredient for anti-aging cosmetic materials.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1467-2494.2004.00224_5.x
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  • 9
    Electronic Resource
    Electronic Resource
    Computation and management of chemical properties in CACTVS: An extensible networked approach toward modularity and compatibility (1994)
    s.l. : American Chemical Society
    Journal of chemical information and modeling 34 (1994), S. 109-116 
    Details
    ISSN: 1520-5142
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/ci00017a013
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  • 10
    Electronic Resource
    Electronic Resource
    Application of a digital 1H-NMR spectrum to the survival test of substructures and the assignment test (1994)
    s.l. : American Chemical Society
    Journal of chemical information and modeling 34 (1994), S. 735-744 
    Details
    ISSN: 1520-5142
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/ci00020a007
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