Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Articles: DFG German National Licenses  (86)
  • 1990-1994  (42)
  • 1985-1989  (44)
  • 1
    Electronic Resource
    Electronic Resource
    Chromosome numbers, genome sizes, cell volumes and evolution of snake-head fish (family Channidae) (1988)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of fish biology 33 (1988), S. 0 
    Details
    ISSN: 1095-8649
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Chromosome number, C-value and cell volume studies were carried out on three species of the genus Channa, viz., C. punctatus, C. striatus and C. gachua. The chromosome number, karyotypic structure and DNA content per cell along with cell volume are reported and described. A series of chromosomal rearrangements are established in three different karyotypes along with polyploidy. Both pericentric inversion and Robertsonian fusion played a major role in chromosome rearrangements. The nuclear DNA content of these three species is within 19-29% of the present-day placental mammals, and is thus lower than the median amount for fishes in general and teleosts in particular. Their lower DNA content suggests that the three species of the family Channidae are highly specialized, and this is supported by their known morphologic, reproductive, behavioural and ecological characteristics.The evolutionary significance of these chromosomal rearrangements, their origin and their mode of establishment are discussed. A probable phylogenetic model based on karyotype, C-value and chromosomal rearrangements of the genus is presented.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1095-8649.1988.tb05523.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Conduction mechanisms in sputtered Ta2O5 on Si with an interfacial SiO2 layer (1989)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 65 (1989), S. 1140-1146 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The temperature dependence of leakage in sputtered Ta2O5 films (10–30 nm) on Si substrates with an interfacial SiO2 layer has been studied for temperatures between –50 and +100 °C and for electric fields between 0 and 2 MV/cm. The activation energy of leakage and the current-voltage relationships have been used to identify various high field conduction mechanisms such as Poole–Frenkel transport at high temperatures and field emission at low temperatures. At low fields and intermediate temperatures, electronic hopping conduction leading to space-charge-limited flow at high current densities has been observed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.343052
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Superconductivity in rapidly quenched metallic systems with nanoscale structure (1993)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 73 (1993), S. 2934-2940 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Nanocomposites of Al-In, Al-Pb, and Zn-Pb have been prepared and characterized using rapid quenching techniques and the nature of superconducting transitions in them has been studied by resistivity measurements. The precipitated second phases (In and Pb) have particle sizes (d) of a few tens of nanometers such that ξ0≥d≥dmin, where ξ0 is the superconducting zero temperature coherence length and dmin is the minimum particle size that supports superconductivity. The onset of superconductivity generally starts in samples with d∼ξ0 and progressively other grains with d≤ξ0 become superconducting. We suggest that the proximity effect of the matrix plays a significant role. In an Al-In system, even with 40 wt.% In, the zero resistivity state is obtained at T∼1.33 times the Tc of Al. But in Al-Pb and Zn-Pb, the zero resistivity state is obtained at T∼4 and 5 times the Tc of Al and Zn with only 10–15 wt % Pb, respectively.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.353024
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Measurement of band offset of a strained-layer single quantum well by a capacitance-voltage technique (1993)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 74 (1993), S. 7618-7620 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We report on a modified Kroemer's analysis [Appl. Phys. Lett. 36, 295 (1980)] for the determination of the band offset ΔEc of a single quantum well from a carrier profile obtained by capacitance-voltage measurement. The procedure is applied to a pseudomorphic GaAs/InGaAs/GaAs strained layer structure.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.354941
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Epitaxial silicon growth conditions and kinetics in low-temperature ArF excimer laser photochemical-vapor deposition from disilane (1992)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 72 (1992), S. 1137-1148 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Homoepitaxial Si films were deposited using an ArF excimer laser beam parallel to the substrate to photodissociate Si2H6 at low temperatures (250–350 °C) under laser intensity and Si2H6 partial pressure conditions that result in low initial photofragment concentrations (〈 1013 cm−3). Total pressure and flow conditions were chosen such that there is little secondary photolysis of the initial photofragments. The deposition yield of solid Si from photoexcited Si2H6 is estimated to be 0.20±0.04, indicating that in order for film growth to result solely from the primary products in ArF laser (193 nm) photolysis of Si2H6, a sticking coefficient ≥0.6 must be assigned to the dominant growth precursor. Growth rates vary linearly with laser intensity and Si2H6 partial pressure over a range of 1–15 mJ/cm2 pulse and 5–40 mTorr, respectively. Increasing the distance between the laser-beam axis and the silicon substrate results in a reduction of the growth rate that can be explained by gas-phase chemical reaction of the growth precursors as they diffuse to the substrate. Epitaxy is maintained for temperatures above the threshold for thermal decomposition of surface (SiH2)n chains at ∼250 °C, and for temperatures below the onset of Si2H6 pyrolysis and rapid thermal desorption of surface H2 at ∼350 °C.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.351791
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    ArF excimer laser induced photolytic growth of Si homoepitaxial films from Si2H6 at 330 °C (1991)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 58 (1991), S. 514-516 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: This letter discusses low-temperature Si homoepitaxy on Si(100) substrates by the photolytic decomposition of Si2H6 by the 193 nm emission of an ArF excimer laser. The chemical vapor deposition process at growth rates from 0.5–4 A(ring)/min is performed in an ultrahigh vacuum chamber which, along with an ex situ HF dip and a novel in situ hydrogen clean using laser excitation, results in minimization of oxygen and carbon contamination which inhibits Si epitaxy. The growth involves photolytic decomposition of Si2H6 and the generation and adsorption of SiH2 precursors on the hydrogenated Si surface, which is the rate limiting step. Very low defect density films in terms of stacking faults and dislocation loops (less than 106 cm−2), and excellent crystallinity have been grown at 330 °C and 0.5 W laser power, as confirmed by Schimmel etching and Nomarski microscopy, transmission electron microscopy, electron diffraction and in situ reflection high-energy electron diffraction.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.104599
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Passivation of GaAs (100) using selenium sulfide (1993)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 73 (1993), S. 4384-4387 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The chemical and electronic aspects of a GaAs (100) surface passivated by selenium sulfide (SeS2) have been investigated by x-ray photoelectron spectroscopy and photoluminescence. It has been observed that this treatment gives rise to an arsenic selenide (As2Se3) terminated surface. No S—GaAs bonds were observed. The remarkable electronic properties and the formation of the chemically and thermally stable As2Se3 phase reveals the successful passivation. Passivation of GaAs in single step and identification of a single selenium species on the surface are considered to be the major advantages of using SeS2.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.352775
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Discontinuity of B-diffusion profiles at the interface of polycrystalline Si and single crystal Si (1993)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 73 (1993), S. 3800-3804 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Boron diffusion in polycrystalline Si-on-single crystal Si systems has been studied by secondary ion mass spectrometry. The extrapolated B-diffusion profiles in polycrystalline Si and in the single crystal Si substrate reveal a discontinuity at the polycrystalline Si-single crystal Si interface. The discontinuity in the B profiles is believed to occur due to the blockage of B-defect complexes by the interfacial oxide between polycrystalline Si and the single-crystal Si substrate, as well as the immobility of these defect complexes in single crystal Si. The B in the implant peak region above the B solid solubility limit is found to be immobile in single crystal Si during annealing due to the formation of electrically inactive B-defect complexes. In polycrystalline Si, however, our results show that the B in the peak region spreads out more rapidly than in single crystal Si possibly due to the diffusion of B-defect complexes along grain boundaries. The B-defect complexes are electrically inactive as determined by spreading resistance analysis. If the B concentration is lowered below the solid solubility limit, either by decreasing the dose or by raising the anneal temperature, no discontinuity is observed in the B profile across the polycrystalline Si-single crystal Si interface.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.352886
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Crystallographic characterization of GexSi1−x/Si superlattices grown by remote plasma-enhanced chemical vapor deposition (1991)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 70 (1991), S. 3324-3328 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Single-crystal GexSi1−x/Si superlattices have been successfully fabricated using remote plasma-enhanced chemical vapor deposition, a novel low-temperature thin-film growth technique. Reflection high-energy electron diffraction, cross-sectional transmission electron microscopy (XTEM), plan view TEM, x-ray-diffraction, and secondary-ion mass spectroscopy techniques have been applied to study the crystallographic properties of the superlattice structures. Arrays of dislocation lines, which are either parallel or perpendicular to each other, have been observed in the superlattices for those cases in which the total layer thickness exceeds the critical layer thickness. The location, orientation, and Burgers vectors of the misfit dislocation lines have been analyzed. Possible mechanisms of the generation of the misfit dislocations are also discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.349265
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Magnetic viscosity of single domain magnetite particles (1991)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 70 (1991), S. 5533-5537 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The acquisition of viscous magnetization has been measured on a single domain magnetite sample in the temperature range 80 to 330 K and in applied fields up to 1540 Oe. Based on Néel's single domain theory, we have calculated the field and temperature dependence of viscous acquisition by numerical two-dimensional integration, using experimentally determined volume and switching field distributions. Predicted and experimental viscosity coefficients do not match, with especially strong discrepancies below the Verwey transition. The experimental acquisition coefficient is larger below the transition than at room temperature, even though the corresponding switching field distributions are nearly identical. Thus we cannot explain single domain viscosity by switching field and volume distributions alone, and we suspect that stress plays a prominent role.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.350211
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...