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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Insectes sociaux 29 (1982), S. 164-174 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Resume ChezLasius sakagamii, le taux de reproduction est en relation avec la densité des reines dans chaque nid. Dans les nids à forte densité de reines, le développement des ovaires et le taux de ponte de chaque reine sont plus faibles que dans les autres nids, alors que le nombre des œufs dans chaque nid est plus élevé. En général, dans les nids à très forte densité de reines (plus du 25 reines par mètre carré de nid) ou avec des faibles rapports ouvrières/reine (moins de 5 000 ouvrières pour une reine), aucune reine ailée n'est produite. C'est aussi le cas des nids où les rapports larves/ouvrière sont élevés (plus de 5 larves par ouvrière). D'autre part, la production des ouvrières et des mâles est plus grande dans les nids à forte densité de reines que dans ceux où la densité de celle-ci est faible.
    Notes: Summary The reproduction rate ofL. sakagamii is related to the queen density in each nest. In nests with higher queen densities, the ovarian development and the egg-laying rate of each queen is lower, though the number of eggs produced per nest is larger. In general, in nests with very high queen densities (more than about 25 queens per square meter of nest) or low worker/queen ratios (less than about 5,000 workers per queen), no alate queens are produced. Further, nests with high larva/worker ratios (more than about 5 larvae per worker) also produce no alate queens. On the other hand, the production of workers and males is larger in nests with high queen densities than in those with low queen densities.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    European journal of pediatrics 144 (1986), S. 516-517 
    ISSN: 1432-1076
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 24 (1968), S. 182-191 
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: The X-ray intensity of Zn Kα radiation emitted from clean cleavage surfaces (110) of zincblende crystals excited by fast electrons, which impinge on the surfaces in the same way as in ordinary electron diffraction experiments, was measured under various diffraction conditions of exciting electrons. The electron energy was about 30 keV. It was found that the X-ray intensity decreases at Bragg conditions by about 10–20%, in an asymmetric way with respect to the glancing angle of the electrons. Some of features of such an anomaly in X-ray intensity have been discussed on the basis of a two-wave dynamical theory of electron diffraction taking account of the phenomenological absorption.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 30 (1974), S. 374-380 
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: With a triple-axis low-energy electron diffractometer, the intensity curves of the specular reflexion 00 from the cleaved face (001) of a MgO crystal were measured against the glancing angle, for the electrons in the energy range from 180 eV to 500 eV and for three crystal azimuths in a range near [010]. By the use of diagrams drawn on the basis of the Ewald construction to indicate the surface wave resonance conditions for various reciprocal rods, a number of fine structures as well as gross features of the intensity curves were interpreted fairly well in terms of the resonance effect.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 31 (1975), S. 32-38 
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: The behaviour of the Kikuchi lines parallel to the shadow edge, which are formed under diffraction conditions in the Bragg case, is experimentally studied for zincblende (ZnS), MgO and rock salt. A line of this group generally has an asymmetric intensity profile across it. Sometimes it shows contrast reversal from an excess appearance in the central range to a defect appearance in the side ranges along the line. These peculiarities become noticeable with the increase in the glancing angle of the incident beam with the crystal surface. It is pointed out that theoretically the form of the line term in the intensity formula for Kikuchi patterns in the Bragg case differs from that in the Laue case. The variation of the line profile, including the effect of contrast reversal, takes place by the change in the intensity formula, in the ratio of the band term to the line term, depending on the scattering vector appropriate to the inelastic electron scattering involved. By assuming approximate forms for the scattering factors for Kikuchi patterns, the observed results are qualitatively explained.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Copenhagen : International Union of Crystallography (IUCr)
    Acta crystallographica 17 (1964), S. 1083-1084 
    ISSN: 0001-5520
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Geosciences
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 26 (1970), S. 60-70 
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: The relation between an anomalous intensity effect in patterns from high energy electron diffraction by crystals, and the so-called resonance effect in LEED, is discussed mainly on the basis of experimental observations with electrons in both energy ranges, using crystals of zincblende, magnesium oxide and gallium arsenide. It is concluded that these two effects are essentially of the same nature. It is pointed out, that the intensity enhancement of the specular spot and other Laue-zone spots, which occurs under conditions of resonance, is particularly conspicuous when the specular spot is also a Bragg reflection spot. The nature of the wavefield generated in the crystal at resonance is discussed in connexion with other phenomena which appear under the resonance condition, such as the overall intensity enhancement of electron scattering, the increase of secondary electron emission and the variation of X-ray emission yield.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 25 (1969), S. 257-264 
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: A survey of the present status of the error problem concerning the experimental structure factor values (F-values) is given, with special reference to the fluctuation, or the reproducibility, of original data obtained by various methods under different experimental conditions. It is pointed out that in most methods the reproducibility of F-values approaches the range of 1% ̃0.5% in favourable cases; the absolute accuracy is lower than this in all but a few examples.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 30 (1974), S. 103-104 
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: Property of the fundamental equations of the dynamical theory of X-ray diffraction given in terms of the electric field E(r), instead of D(r), is discussed, and some merits of the equations in terms of E(r) are pointed out.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 35 (1979), S. 349-350 
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Type of Medium: Electronic Resource
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