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  • 1
    Electronic Resource
    Electronic Resource
    Resource quality and spatial variation in sex ratios of a free-living solitary sawfly, Dineura virididorsata (Hym., Tenthredinidae) (1993)
    Springer
    Oecologia 96 (1993), S. 420-425 
    Details
    ISSN: 1432-1939
    Keywords: Biased sex ratios ; Dineura virididorsata ; Sex-related survival ; Local mate competition ; Foliage quality
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The sex ratio in final-instar larvae of a birch-feeding, free-living solitary sawfly, Dineura virididorsata, was investigated in Finnish Lapland. The prepupal proportion of females, pooled over ten sites, was 56%, and at four individual sites the sex ratio was significantly female-biased. Larval survival from egg to prepupae did not differ between the sexes. This suggests a femalebiased primary sex ratio in the field. The sex ratio varied among the sites but not among host trees within sites. Contrary to previous results with hymenopterans, we did not find that differences in the sex ratio depended on forage quality: site-specific or tree-specific sex ratios did not correlate with the average prepupal weight. A literature search indicated that female-biased sex ratios are also common in other free-living sawflies. We are unable to explain sex ratios of Dineura virididorsata or other free-living sawflies with existing general models.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00317514
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    Paper (German National Licenses)
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  • 2
    Electronic Resource
    Electronic Resource
    Reproductive behaviour of mated and virgin females of a solitary sawflyDineura virididorsata (1994)
    Springer
    Entomologia experimentalis et applicata 70 (1994), S. 83-90 
    Details
    ISSN: 1570-7458
    Keywords: Hymenoptera ; Symphyta ; Tenthredinidae ; Dineura virididorsata ; sawfly ; sex ratio ; oviposition behaviour ; mating behaviour
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Sex ratios of the arrhenotokous sawflyDineura virididorsata Retz. (Hymenoptera: Tenthredinidae) are variable among populations in the field, but are biased in favour of females. We have concluded elsewhere that the sex ratios of this species cannot be satisfactorily explained by any general sex ratio model that is available. Here we present data on the different behavioural traits that are relevant to interpretation of the evolution of female-biased sex ratios under local mate competition. We report on oviposition behaviour, mating behaviour and the patterns of movement of ovipositing virgin and mated females. Our results show that adult emergence is synchronous and females will mate daily with different males (in the laboratory, at least). This would decrease the relatedness of offspring should it also take place in the field. In addition, ovipositing females (mated and virgin) leave their site of release in a relatively short time and deposit few eggs relative to their capabilities, so siblings are unlikely to be clumped. The time that virgins spend in deposition of an egg is not different from that spent by mated females, so there is no differential ‘investment’ in this regard. These behavioural observations agree with our previous conclusion that the preconditions of current sex ratio theories are not met byD. virididorsata.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02380634
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  • 3
    Electronic Resource
    Electronic Resource
    Slip velocity of particulate solids in vertical tubes (1966)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 12 (1966), S. 1070-1074 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: An equation using only easily determined physical properties of particles has been developed for calculating the slip velocity of nonspherical particulate solids falling in fluid media in the intermediate flow range where neither the Stokes nor Newton law applies. The variation in Reynolds numbers covered by this work ranged from 12 to 460. Slip velocities calculated from the equation differed from experimental data by an average deviation of only 3.7% when solids of a wide range of diameters (156 to 1,247 microns), densities (71 to 475 lb./cu. ft.), surface shape factors (0.40 to 0.97), and gases of a wide density range (0.01 to 0.31 lb./cu. ft.) were utilized. Thirty-eight different gas-solid systems were studied.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690120607
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  • 4
    Electronic Resource
    Electronic Resource
    Prediction of the properties of model polymer solutions and blends (1994)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 40 (1994), S. 878-887 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: In this work we present an extension of the statistical associating fluid theory (SAFT) developed for associating fluids by applying this extension to polymer solutions and blends. The polymer molecule is modeled as a flexible chain made of bonded spherical segments. These segments interact with the Lennard-Jones potential. The extension of SAFT is compared with molecular simulation results for polymer solutions and blends. Since the same force model is used in the simulation and theory, this comparison is a strong test of the assumptions made in deriving the theory. Results are presented for pure polymers of up to 50 segments long, polymer solutions of a polymer 20 segments long dissolved in its own monomer, and blends of polymers of 25 segments each. The theory produces results that are in better agreement with simulation results than the Flory-Huggins theory for the systems studied.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690400514
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  • 5
    Electronic Resource
    Electronic Resource
    Estimation of pressure drop for vertical pneumatic transport of solids (1967)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 13 (1967), S. 608-611 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690130338
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    Paper (German National Licenses)
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