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  • 1
    Electronic Resource
    Electronic Resource
    Investigation of galaxy and quasar luminosity evolution in the model of standard cosmology (1992)
    Springer
    Astrophysics and space science 190 (1992), S. 9-22 
    Details
    ISSN: 1572-946X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract It is shown that the Hubble curvem(z) for galaxies and quasars averaged over a large volume of data forms in the first approximation a single continuous curve in the interval of red shifts 10−2.5≤z≤4.5, which is satisfactorily described by the dependence $$\bar m_v \left( Z \right) = 4\log z + 2z - 0.4z^2 + 20$$ . A large deviation of the observed mean dependence from the theoretical one predicted by the standard cosmology is explained by the evolution of the galaxy and especially quasar luminosity. The corresponding mid-statistical function of the absolute luminosity variation for the last 4/5 times of existence in the Universe is equal toM(z)−M(z 0)=logz/z 0+2z−0.4z 2. The luminosity of the most far distant from the observed quasars on the average by 5–6 stellar magnitudes high than the luminosity of near galaxies and quasars. It is obtained that even the most far distant quasars atz≈5 are in the maximum of luminosity, or their extinction has just began, thus the quasar formation should be expected forz〉(5–6). The relative rate of the luminosity decrease of galaxies and near quasars is rather accurately amounts in the recent epoch 7% per 109 years. The obtained average Hubble curve of galaxies and quasars is evidently the main cause of their evolution in the Universe.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00644562
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    Paper (German National Licenses)
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  • 2
    Electronic Resource
    Electronic Resource
    A study of the products of the hydrolysis of the xylan ofMelilotus albus by endo-1 4-β-xylanase (1981)
    Springer
    Chemistry of natural compounds 16 (1981), S. 338-342 
    Details
    ISSN: 1573-8388
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The enzymatic hydrolysis of a 4-0-methylglucuronoxylan of white sweetclover (Melilotus albus) by a highly purified homogeneous endo-1, 4-β-xylanase fromAspergillus niger 14 has shown that the enzyme hydrolyzes 97% of the polysaccharide in 72 h. Acidic and neutral oligosaccharides were found in the hydrolysate after the action of the enzyme. An investigation of the hexauronic acid isolated has shown that the glucuronic acid is attached to the nonreducing end of the xylooligosaccharide, which demonstrates the specific action of the enzyme on the polysaccharide.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00568362
    Library Location Call Number Volume/Issue/Year Availability
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    Paper (German National Licenses)
    Fulltext
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