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  • 1
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 90 (2001), S. 2730-2736 
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The effects of growth temperature, substrate offcut, and dislocation pileup formation on threading dislocation density (TDD) in compositionally graded SiGe buffers are explored. To investigate dislocation glide kinetics in these structures, a series of identical samples graded to 30% Ge were grown at temperatures between 650 and 900 °C on (001)-, (001) offcut 6° towards an in-plane 〈110〉-, and (001) offcut 6° towards an in-plane 〈100〉-oriented Si substrates. The field threading dislocation density (field TDD) in the on-axis samples varied exponentially with temperature, from 3.7×106 cm−2 at 650 °C to 9.3×104 cm−2 at 900 °C. The activation energy for dislocation glide in this series, calculated from the evolution of field TDD with growth temperature, was 1.38 eV, much lower than the expected value for this composition. This deviation indicates that strain accumulating during the grading process at low growth temperatures is forcing further dislocation nucleation, resulting in a deviation from pure glide-limited relaxation. The TDD of samples grown on offcut substrates exhibited a more complicated temperature dependence, likely because films grown on offcut substrates have an increased tendency towards saturation in dislocation reduction reactions at high temperature. Dislocation reduction processes were further explored by initiating compositional grading up to 15% Ge at 650 °C and continuing the grade to 30% Ge at 900 °C. The low temperature portion of this growth provided an excess concentration of threading dislocations which could subsequently be annihilated during the high temperature portion of the growth, enabling a comparison of reduction rates for different substrate offcuts. Combining these results with threading dislocation densities in a variety of other samples, a complete picture of strain relaxation kinetics in compositionally graded SiGe/Si emerges. Generally, strain relaxation in these structures is limited by dislocation glide, and threading dislocation densities are independent of final Ge content. However, we theorize that dislocation pileup formation inhibits the strain relaxation process and is therefore accompanied by a rise in field threading dislocation density. Based on these results, we now have a predictive model for TDD in compositionally graded SiGe/Si over a wide range of growth conditions. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Journal of medicinal chemistry 5 (1962), S. 808-815 
    ISSN: 1520-4804
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Journal of food science 42 (1977), S. 0 
    ISSN: 1750-3841
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Bakers and brewers yeasts, yeast cell walls (bakers yeast glycan), and a protein isolate from yeast (bakers yeast protein) incorporated into the diets of rats partially or totally prevent the elevation of the serum cholesterol in rats fed cholesterol and cholic acid as a hypercholester-olemic agent. The degree of response depends upon the level of yeast' product in the diet. Bakers yeast glycan incorporated into the diet of hypercholesterolemic rats rapidly and markedly lower the serum cholesterol.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 0009-840X
    Source: Cambridge Journals Digital Archives
    Topics: Classical Studies
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Cambridge : Cambridge University Press
    The @classical quarterly 44 (1994), S. 7-16 
    ISSN: 0009-8388
    Source: Cambridge Journals Digital Archives
    Topics: Classical Studies
    Notes: The papyrus text of the Partheneion, discovered in 1855 and now in the Louvre, consists of 101 lines in three columns. Of these the first 34 lines (column i) are badly mutilated owing to the disappearance of the left-hand side of the column, whereas lines 35–101 (columns ii and iii) can be restored with almost complete confidence. Of a fourth column nothing is legible, though a coronis opposite the fifth line of column iii shows that the poem ended only four lines after our text runs out. The lengths of the existing columns are 34 lines (i), 34 lines (ii), 33 lines (iii). If a full column of 35 lines has been lost before our column i—a pre-eminently reasonable hypothesis—the entire poem will have consisted of 140 lines. Since each strophe consists of fourteen lines, we may thus imagine the whole to have consisted of ten strophes. By a curious coincidence the part of the poem which is almost intact and which deals with the occasion consists of five strophes or seventy lines: it seems to be the case, thus, that the lost or damaged part also consisted of five strophes or seventy lines of choral lyric and dealt with myth: what we can make out, certainly, appears to be exclusively myth and attendant moralising.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 166 (1950), S. 1109-1110 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Results obtained with a-particles seem to provide the most satisfactory basis of comparison. Integral bias curves have been obtained using ±-particles (6.04 and 872 MeV.) from thorium C and . This procedure has the further advantage that thin crystals with an area of one or two square ...
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 206 (1965), S. 1253-1253 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] A mass spectrometer was used to examine the spectra of the various gases in which these species were observed. Gas from a reservoir at pressures up to 200 torr passed through a narrow orifice (diameter and length 2 x 10 4 cm) directly into the ionizing electron beam, of the spectrometer. As the ...
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    BBA Section Nucleic Acids And Protein Synthesis 149 (1967), S. 302-304 
    ISSN: 0005-2787
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Biology
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Cambridge : Cambridge University Press
    The @classical quarterly 40 (1990), S. 307-318 
    ISSN: 0009-8388
    Source: Cambridge Journals Digital Archives
    Topics: Classical Studies
    Notes: Hieron of Syracuse was the most powerful Greek of his day. He was also, and the two facts are not unrelated, the most frequent of Pindar's patrons. A singular feature of the four poems for this Sicilian prince is their obsession with sin and punishment: Tantalus in the First Olympian, Typhoeus, Ixion, and Coronis in the first three Pythians – all offend divinity and suffer terribly. But even in this company, where glory comes trailing clouds of pain, the Third Pythian stands out. The other three odes are manifestly epinician and celebrate success, both athletic and military. The Second Pythian, for instance, is a sombre canvas, and a motif of ingratitude dominates the myth. Yet it rings at the outset with praise of Syracuse and of Hieron's victory. The Third Pythian, by comparison, is not obviously a victory ode.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Cambridge : Cambridge University Press
    The @classical quarterly 36 (1986), S. 317-321 
    ISSN: 0009-8388
    Source: Cambridge Journals Digital Archives
    Topics: Classical Studies
    Notes: In the Eighth Olympian, for Alcimedon of Aegina, Pindar recounts a story (31–46) that, according to a notice in the scholia, is not found in earlier Greek literature. Aeacus was summoned from Aegina to Troy by Apollo and Poseidon to help in the construction of the city's fortifications. Smoke, says the poet, would one day rise from the very battlements Aeacus built. The wall newly completed, a portent appeared: three snakes tried to scale the ramparts but two fell to earth while one succeeded in entering the city. Apollo immediately interpreted this sign: Troy would be taken ‘owing to the work of Aeacus’ hand' and would, moreover, be taken ‘by the first and the fourth generations’.If there is literary invention here, it would seem that Pindar has drawn inspiration from three passages of our Iliad: (i) 7.452–3, Apollo and Poseidon toiled to build a wall for Laomedon; (ii) 6.433–4, there was one spot in the wall of Troy that was especially vulnerable; (iii) 2.308–29, the seer Calchas declares an omen involving a snake to signify the eventual destruction of Ilium.The general import of the passage is clear enough — descendants of Aeacus play a prominent part in the Trojan war and in the capture of the city. But the details of the portent and of the prophecy have caused much perplexity, for they cannot easily be made to correspond to the history they prefigure. It is the numbers in Pindar's account that are the chief source of confusion.On the model of the omen interpreted by Calchas (where a snake eating nine birds represents a lapse of nine years before the sack of the city) the three snakes in the Pindaric story might reasonably be expected to represent the lapse of three generations before Aeacus' great-grandson Neoptolemus played his conspicuous part in the final agony of Troy. But this interpretation of the portent forces us to explain away the fact that Troy was also destroyed by Aeacus' son, Telamon, as Pindar repeatedly insists in his Aeginetan odes (Nem. 3.37, 4.25; Isth. 6.26–31): if the snakes are taken to represent generations, one of the unsuccessful snakes in fact represents a successful conqueror. This is a disturbing inconcinnity.
    Type of Medium: Electronic Resource
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