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  • 1
    Electronic Resource
    Electronic Resource
    Temperature dependence of two-beam coupling and dark decay in photorefractive BaTiO3 (1996)
    Springer
    Optical and quantum electronics 28 (1996), S. 1509-1520 
    Details
    ISSN: 1572-817X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology , Physics
    Notes: Abstract The temperature dependence of two-beam coupling and dark decay in photorefractive BaTiO3 is reported. We show that the competition between deep and shallow traps depends on temperature and writing intensity, and influences two-beam coupling and dark decay. The dynamics of dark decay, characterized by a fast decay of partial erasure and a subsequent slow decay, is influenced by the presence of deep and shallow traps. Partial erasure, due to thermal excitation of charges from the shallow traps, decreases with temperature and increases with writing intensity. The time constant of the slow decay, due to thermal excitation of charges from the deep traps, depends strongly on temperature, but not on the writing intensity. At room temperature, the existence of deep and shallow trap leads to intensity-dependent photorefractive gains. As temperature increases, the influence from the shallow trap decreases, and the photorefractive gain becomes independent of the intensity. However, at much higher temperatures (∼100°C), the photorefractive gain resumes its dependence on intensity due to an increase in dark conductivity at elevated temperature.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00326221
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  • 2
    Electronic Resource
    Electronic Resource
    Anodic dissolution of galena concentrate in perchloric acid (1978)
    Springer
    Journal of applied electrochemistry 8 (1978), S. 25-32 
    Details
    ISSN: 1572-8838
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Electrical Engineering, Measurement and Control Technology
    Notes: Abstract A basic study has been made on the anodic dissolution of lead sulphide ore (galena) in perchloric acid. The electrodes used in the research were fabricated by melting and casting the ore in a suitable mould. The phases which were present in sufficient quantities to be detected by X-ray diffraction were PbS and ZnS. Coulombic efficiencies were determined at 40° C at various levels of pH and current density, and were in the range of 90% for most of the tests. Transient studies revealed a non-uniform surface attack and that the dissolution reaction was irreversible, as indicated by the absence of cathodic currents, in the vicinity of the rest potential. Steady-state studies showed the reaction to be activation controlled and that the rate-determining step was a chemical reaction following the first electron transfer.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00615390
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  • 3
    Electronic Resource
    Electronic Resource
    Morphology of poly(ether sulfone)-modified polycyanurates (1997)
    Springer
    Journal of polymer research 4 (1997), S. 203-211 
    Details
    ISSN: 1572-8935
    Keywords: Aromatic dicyanate ; Phase separation ; Fracture surface ; Iminocarbonate
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract Polycyanurates prepared from cure of bisphenol A dicysanate (BPADCy) were modified with either hydroxyl-terminated or cyanated poly(ether sulfone)s (as HPES or CPES, respectively) of different molecular weights. With high molecular weight HPES (or CPES), the resulting resin showed a two-phase morphology in contrast to the single-phase morphology generated from the curing reactions of the low molecular weight HPES (or CPES) and BPADCy as observed from optical microscopy. Results from scanning electron microscopy suggests a discrete-continuous fracture surface for the high molecular weight HPES-modified polycyanurate but for the CPES-modified analogue, a blur interface between particle and matrix was observed. However, this blur interface can also be generated if 1 wt% of catalyst system (n-nonylphenol/cobaltic acetylacetonate) was used during cure of mixtures of high molecular weight HPES and BPADCy. This blur interface in the catalyzed system is attributed to the inter-reactions between the hydroxyl termini in HPES and the cyanate groups in BPADCy.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s10965-006-0026-y
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  • 4
    Electronic Resource
    Electronic Resource
    Pump-energy-dependent photo-ionization and collisional ionization in two-photon-resonant- and three-photon-ionization processes (1998)
    Springer
    Applied physics 66 (1998), S. 617-620 
    Details
    ISSN: 1432-0649
    Keywords: PACS: 32.80.Rm; 34.50.Fa
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s003400050446
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  • 5
    Electronic Resource
    Electronic Resource
    Physiological and symbiotic characteristics of Rhizobium fredii isolated from subtropical-tropical soils (1988)
    Springer
    Biology and fertility of soils 5 (1988), S. 350-354 
    Details
    ISSN: 1432-0789
    Keywords: Rhizobia ; Effective N2-fixation ; Osmotic pressure ; Symbiosis ; Glycine max ; Rhizobium fredii ; Rhizobium japonicum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Physiological and symbiotic characteristics were identified in Rhizobium fredii isolated from subtropical-tropical soils. The generation times of R. fredii Taiwan isolated-SB 357 and -SB 682 were 1.7 and 2.5 h, respectively. These strains were associated with acid production in yeast-extract mannitol medium. They were able to use hexoses, pentose, sucrose, trehalose and raffinose. Strain SB 357 can resist a high concentration of kanamycin (100 μg ml−1 and penicillin (400 μg ml−1). It can tolerate up to 2.34% NaCl and 1031.3 mosmol kg−1 (23.4 bars). The growth rate of R. fredii SB 357 under the concentration of approximately 450 mosmol kg−1 (10.2 bars) was not affected by salinity, but responded to osmotic pressure. Both strains (SB 357 and SB 682) isolated from subtropical-tropical soils were able to form an effective N2-fixing symbiosis with the US soybean cv Clark lanceolate leaflet.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00262145
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  • 6
    Electronic Resource
    Electronic Resource
    A very large poritid colony at Green Island, Taiwan (1999)
    Springer
    Coral reefs 18 (1999), S. 42-42 
    Details
    ISSN: 1432-0975
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s003380050151
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  • 7
    Electronic Resource
    Electronic Resource
    Minimum area circumscribing Polygons (1985)
    Springer
    The visual computer 1 (1985), S. 112-117 
    Details
    ISSN: 1432-2315
    Keywords: Geometric algorithms ; Circumscribing ; Optimization ; Convex polygons ; Minimum area
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Notes: Abstract We show that the smallestk-gon circumscribing a convexn-gon can be computed inO(n 2 logn logk) time.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01898354
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  • 8
    Electronic Resource
    Electronic Resource
    An optimal approximation algorithm for the rectilinearm-center problem (1990)
    Springer
    Algorithmica 5 (1990), S. 341-352 
    Details
    ISSN: 1432-0541
    Keywords: Rectilinearm-center problem ; NP-completeness ; Approximation algorithm
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Notes: Abstract Given a set ofn points on the plane, the rectilinearm-center problem is to findn rectilinear squares covering all thesen points such that the maximum side length of these squares is minimized. In this paper we prove that there is no polynomial-time algorithm with an error ratio ɛ 〈 2 for the rectilinearm-center problem unless NP = P. A polynomial-time approximation algorithm with an error ratio of 2 is also proposed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01840393
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  • 9
    Electronic Resource
    Electronic Resource
    A new structure of 780 nm AlGaAs/GaAs high power laser diode with non-absorbing mirrors (1999)
    Springer
    Applied physics 68 (1999), S. 467-470 
    Details
    ISSN: 1432-0630
    Keywords: PACS: 78.20.Wc; 78.45.+h; 78.40.Fy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s003390050925
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  • 10
    Electronic Resource
    Electronic Resource
    The effect of Aspergillus oryzae fermentation extract on the anaerobic fungus Neocallimastix frontalis EB 188: effects on physiology (1996)
    Springer
    Applied microbiology and biotechnology 45 (1996), S. 811-816 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  Aspergillus oryzae fermentation extract (Amaferm) was used to stimulate the in vitro growth of the cellulolytic fungus Neocallimastix frontalis EB 188. Soluble and filter-sterilized extract was added either at the start or throughout culture growth. Culture mass, protein secretion and cellulase secretion were measured in stationary test-tubes or round-bottom flasks and a stirred (desktop) fermenter. The soluble extract increased culture mass and protein and cellulase secretion in a dose-dependent manner. Maximum stimulation caused the supernatant cellulase to nearly double (i.e., 87% over controls; P〈0.05), cell mass increased by 27% (P〈0.05) over controls and secreted protein increased 37% (P〈0.05) over controls. The timing of extract addition did not alter the culture response and suggested a recycling of components. The robustness of fungal zoospores used as inoculum, however, greatly influenced the effectiveness of the extract to stimulate secretions. Extracts did not directly influence the pH of the culture medium or the endogenous levels of enzymes. The rate of carbon source utilization and morphology of the fungus were unchanged by soluble-extract additions at any level tested. The extract was inhibitory when added to concentrations exceeding an amount equivalent to 20 g animal-1 day-1.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002530050767
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