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  • 1985-1989  (5)
  • 1980-1984  (2)
  • 1965-1969  (4)
  • 1935-1939  (1)
Material
Years
Year
  • 1
    Electronic Resource
    Electronic Resource
    New York, NY : American Institute of Physics (AIP)
    Physics of Fluids 1 (1989), S. 1911-1925 
    ISSN: 1089-7666
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Calculations are shown of the structure of plasmas in equilibrium with solid surfaces that reemit incident plasma ions as relatively cold neutral gas. A numerical transport model that includes a Fokker–Planck treatment of ion–ion collisions obtains the distribution function for ions in a phase space of one spatial coordinate and two velocities. This is done self-consistently with an electrostatic potential, a Maxwell–Boltzmann description of electrons, and electron impact ionization of the reemited neutrals. Solutions are obtained from a higher temperature kinetic regime where Coulomb collisions are nearly negligible to a lower temperature regime where plasma behavior is approximately fluidlike. A result of these calculations is the resolution of an ambiguity posed by previous kinetic regime calculations that omitted ion–ion collisions and obtained a family of solutions for each set of physical parameters [Phys. Rev. Lett. 49, 650 (1982); Phys. Fluids B 1, 448 (1989)]. The physically correct solution for semi-infinite surface plasmas is shown to be the member of each family that maximizes the ion thermal conduction to the surface and the magnitude of a maximum in the electrostatic potential that is found in these and the previous calculations. Further results are in agreement at lower temperatures with solutions obtained from a fluid model and the identification of the correct boundary condition on normal flow velocity to be used in fluid models.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Physics of Fluids 28 (1985), S. 3676-3682 
    ISSN: 1089-7666
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The linear stability of an ablating plasma is investigated as an eigenvalue problem by assuming the plasma to be at the stationary state. For various structures of the ablating plasma, the growth rate is found to be expressed well in the form γ=α(kg)1/2 −βkVa, where α=0.9, β(approximately-equal-to)3–4, and Va is the flow velocity across the ablation front, and is found to agree well with recent two-dimensional simulations in a classical transport regime. Short-wavelength lasers inducing enhanced mass ablation are suggested to be advantageous to stable implosion because of the ablative stabilization.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    New York, NY : American Institute of Physics (AIP)
    Physics of Fluids 1 (1989), S. 448-467 
    ISSN: 1089-7666
    Source: AIP Digital Archive
    Topics: Physics
    Notes: A numerical study is done of a plasma in contact with a solid surface that reemits some fraction of the incident plasma as neutral gas. The calculation uses a steady-state, kinetic treatment of the transport equations in one space dimension and one or two velocity dimensions to determine self-consistently the distribution functions of the interacting species and the electrostatic potential. The dominant phenomena are the ionization of the neutral gas and the acceleration of the resulting ions away from a potential maximum that is predicted to form in the ionization region. Other effects involved are a Debye sheath structure between the solid surface and the potential maximum, and collisional trapping and untrapping of electrons in the well represented by the potential maximum. Results are presented from a nondimensional model with a monatomic returning neutral species, and for diatomic molecular deuterium returning from the surface. For each set of physical parameters chosen, a one parameter family of solutions is obtained. A hypothesis is presented for the choice from this family of solutions that would be found experimentally.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Entomology 27 (1982), S. 229-252 
    ISSN: 0066-4170
    Source: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Topics: Biology
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 208 (1965), S. 1215-1216 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] By sharp contrast, less than half the neurones in the cuneate nucleus of the monkey seem to be under cortical influence-and those that are often suffer a mixed influence, depending on the site of cortical stimulation. Furthermore, quite iinlike that in the cat, cortical excitation in the monkey can ...
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Microchimica acta 56 (1968), S. 297-303 
    ISSN: 1436-5073
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Ein Verfahren der chromatographischen Trennung und radiometrischen Fällung zur Bestimmung von Nickel in der Größenordnung von Mikrogramm bis Submikrogramm wurde beschrieben. Mit einem geeigneten Lösungsmittel wird Nickel vollständig von allen störenden Faktoren auf einem Chromatogrammstreifen isoliert und dann als Ni35S gefällt. Durch Radioautographie und Radiometrie erhält man quantitative Ergebnisse.
    Notes: Summary A technique combining Chromatographic separation with radiometric precipitation is described in which nickel is determined at theμg to submicrogram range. An appropriate solvent completely isolates nickel from interference on a Chromatographic strip. Nickel is then precipitated as the35S labeled nickel sulfide. Quantitative yields are obtained using radioautography and radiometry.
    Type of Medium: Electronic Resource
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  • 7
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    Unknown
    Philadelphia : Periodicals Archive Online (PAO)
    Social studies. 28:2 (1937:Feb.) 62 
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  • 8
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 210 (1966), S. 652-653 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] This device consists of a flat surface over which steel wires are stretched at J-in. (6-36-mm) intervals. The wires are alternately grounded and charged. The bees, on being shocked, sting down through a sheet of nylon parchment taffeta; the venom is left on the underside of the nylon when the sting ...
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Insectes sociaux 31 (1984), S. 221-237 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Resume La production de cellules royales après orphelinage accidentel fut examinée dans des colonies d'abeilles de différentes races européennes. Treize colonies ont été quotidiennement placées dans un orphelinat expérimental après l'apparition d'une nouvelle reine. Des observations ont été faites sur le nombre de cellules, le “timing” de la reconstruction des cellules royales, l'emplacement des cellules à l'intérieur du nid, l'âge des larves sélectionnées en vue de l'élevage des reines, le taux de mortalité des cellules et le phénomène d'exhibition de la glande de Nassanoff des ouvrières dans les colonies orphelines. On a pu détecter la perte d'une reine après 6 à 12 heures; celle-ci fut tout d'abord indiquée par le fait qu'un certain nombre d'abeilles exhibent leur organe odorant lors de l'ouverture de la ruche, et l'élaboration de la cupule royale. Le nombre des ouvrières exposées a atteint son record entre 12 et 24 heures puis s'est mis à décroître, alors que les cellules royales augmentaient. Le temps requis pour l'initiation des cellules royales a varié entre 12 et 48 heures, selon les colonies. Les cellules royales de remplacement ont commencé ordinairement à se former sur des larves d'ouvrières de moins de 2 jours (64,7%), mais des cellules se sont développées sur des larves âgées de 3 (25,3%) à 4 jours (10,0%). Sur 268 cellules, 2 étaient uniquement formées à partir d'œufs, dont un seul survivait et devenait une larve mâle. Dans six des colonies, des cellules royales se sont développées à partir de larves mâles, mais celles-ci furent immédiatement détruites soit avant, soit juste après l'operculation. Le taux de développement de cellules royales était de 9,3% par rapport aux cellules mâles. Le taux de développement de nouvelles cellules royales après la perte d'une reine a été assez élevé pendant une période de 2 à 4 jours, mais s'est mis à décroître bien que de nouvelles cellules royales se formaient entre 8 et 9 jours après le début de l'orphelinage. Nous avons noté un taux record de cellules produites par une colonie vers le 3e ou 4e jour, qui s'est ensuite réparti de façon plus égale. Le taux de mortalité des cellules a alors provoqué la baisse du nombre total des cellules. Le nombre des cellules royales des colonies a varié entre 11 et 49, c'est-à-dire une moyenne de 20,4; le taux de mortalité des cellules s'est avéré de 39,1%. Les cellules royales étaient bien distribuées dans tout le nid à couvain, mais surtout vers le fond du cadre, et loin de l'entrée de la ruche.
    Notes: Summary Emergency queen cell production was examined in honey bee colonies of mixed European races. Thirteen colonies were dequeened and followed on a daily basis until after queen emergence. Observations were made on the number of cells, the temporal sequence of queen cell construction, cell location within the nest, the age of larvæ selected for queen rearing, mortality of immature queens and the scenting behavior of workers in queenless colonies. Queen loss was detected within 6–12 hours and was first indicated by an increase in scenting behavior (on colony disturbance) and queen cup construction. The number of scenting workers reached a peak in 12–24 hours and then declined, as queen cell numbers increased. The time of queen cell initiation varied from 12–48 hours in different colonies. Emergency queen cells were usually started over worker larvæ less than 2 days of age (64.7%), but cells were built over 3 (25.3%) and 4 (10.0%) day old larvæ. Only 2 of 268 cells (0.8 %) were started over eggs; one survived and developed into a drone larva. In 6 colonies emergency queen cells were started over drone larvæ but these were destroyed immediately before or shortly after capping. The overall rate for queen cell construction over drone larvæ was 9.3%. The rate at which new queen cells were started after queen loss was high for two to four days, but then declined although new queen cells were started as late as eight or nine days after queen removal. The number of cells produced by a colony usually peaked by the third or fourth day and then leveled. Slight declines in total cell number often occurred because of cell mortality. The number of queen cells started by colonies varied from 11–49 with a mean of 20.4; cell mortality averaged 39.1%. Queen cells were well distributed throughout the brood nest but placement was biased toward the bottom of the frames and away from the entrance.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Insectes sociaux 32 (1985), S. 217-220 
    ISSN: 1420-9098
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung Honigbienen (Apis mellifera) bevorzugen ehemals bewohnte Brutkästen bei der Wahl zwischen noch nie benutzten und vormals von Bienen bewohnten Brutkästen mit Wabe (p=0.032). Dieses Verhalten ist möglicherweise adaptiv in Bezug auf Energieersparnis, verglichen mit einer neuen Kolonie. Die Wahl eines vormals bewohnten Brutkästens könnte jedoch den einfachen Grund haben, daß bereits benutzte Brükästen mit Wabe für die Bienen auffälliger und leichter zu finden sind.
    Notes: Summary Given a choice between nesting in boxes which had been previously occupied by bees, containing comb, and boxes never occupied, honey bees (Apis mellifera) show a significant (p=0.032) preference for the previously occupied cavities. This behavior may be adaptive in terms of energetic savings to a new colony, or cavities with comb may simply be more conspicous.
    Type of Medium: Electronic Resource
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