Bibliothek

X
feed icon rss

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
  • 1
    Digitale Medien
    Digitale Medien
    Solubilization and Characterization of σ-Receptors from Guinea Pig Brain Membranes (1989)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of neurochemistry 53 (1989), S. 0 
    Details
    ISSN: 1471-4159
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Medizin
    Notizen: Abstract: The σ-receptor, a distinct binding site in brain tissue that may mediate some of the psychotomimetic properties of benzomorphan opiates and phencyclidine, has been sol-ubilized using the ionic detergent sodium cholate. Binding assays were performed with the solubilized receptor using vacuum filtration over polyethyleneimine-treated glass fiber filters. The pharmacological specificity of the solubilized binding site for σ-receptor ligands is nearly identical to the membrane-bound form of the receptor, with the order of potencies for displacement of the selective σ-ligand [3H]di-o-tolylguanidine ([3H]DTG) closely correlated. The stereoselectivity for (+)-benzomorphan opiate enantiomers was retained by the solubilized receptor. The soluble receptor retained high affinity for binding of [3H]DTG (KD= 28 ± 0.5 nM) and (+)-[3H]3-(3-hydroxyphenyl)-N-(l-propyl)piperi-dine {(+)-[3H]3-PPP} (KD= 36 ± 2 nM). Photoaffinity labeling of the solubilized receptor by [3H]p-azido-DTG, a σ-selective photoaffinity label, resulted in labeling of a 29-kilodalton polypeptide identical in size to that labeled in intact membranes. Estimation of the Stokes radius of the [3H]DTG binding site was obtained by Sepharose CL-6B chromatography in the presence of 20 mM cholate and calculated to be 8.7 nm. This value was identical to the molecular size found for the binding sites of the σ-selective ligands (+)-[3H]3-PPP and (+)-[3H]SKF-10,047, supporting the hypothesis that all three ligands bind to the same macro-molecular complex.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1111/j.1471-4159.1989.tb08554.x
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 2
    Digitale Medien
    Digitale Medien
    Influence of interfacial contamination on the structure and barrier height of Cr/GaAs Schottky contacts (1989)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 54 (1989), S. 356-358 
    Details
    ISSN: 1077-3118
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: The structure of as-deposited and annealed Cr/GaAs Schottky contacts was investigated by high resolution and analytical electron microscopy. The Schottky barrier height for contacts prepared by cleavage and in situ metallization in ultrahigh vacuum was stable upon annealing up to 370 °C in N2. In contrast, the contacts prepared on air-exposed substrates show an increase of the barrier height by 80 meV during annealing in the same range of temperatures. Comparing these two types of contacts, distinct differences in the grain size, presence of an oxide layer at the interface, and change in stoichiometry in the substrate beneath the contact were detected.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.100968
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 3
    Digitale Medien
    Digitale Medien
    Effect of boron on the deep donors (DX centers) in GaAs:Si (1989)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 54 (1989), S. 1344-1346 
    Details
    ISSN: 1077-3118
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: We found that, when boron was introduced into GaAs:Si, the deep donors induced by pressure exceeding 20 kbar reported previously by M. Mizuta, M. Tachikawa, H. Kukimoto, and S. Minomura [J. Appl. Phys. 24, L143 (1985)] disappeared while new donor levels with reduced binding energies and capture barrier heights appeared. It is proposed that B atoms paired up with Si donor atoms and the resultant change in the short-range potential of the Si donor atoms depressed the capture barrier height of the pressure-induced deep donor.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.100710
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 4
    Digitale Medien
    Digitale Medien
    Structure and electrical properties of TiN/GaAs Schottky contacts (1988)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 52 (1988), S. 2160-2162 
    Details
    ISSN: 1077-3118
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: The interface structure and morphology of TiN/GaAs contacts before and after annealing at 500, 700, and 850 °C have been investigated by transmission electron microscopy. Results reveal that pocket-like protrusions are formed beneath the interface after annealing at 500 °C. These pockets increased in number and maximum size with increased annealing temperature. Outdiffusion of Ga and/or As along high angle grain boundaries between columnar structure of the as-deposited TiN thin film has been proposed as being responsible for the pocket formation. The changes of electrical characteristics of these materials after annealing have been related to the formation of these pockets.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.99564
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 5
    Digitale Medien
    Digitale Medien
    Lattice relaxation of pressure-induced deep centers in GaAs:Si (1987)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 51 (1987), S. 349-351 
    Details
    ISSN: 1077-3118
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: Deep centers induced by hydrostatic pressure in GaAs:Si have been studied by deep level transient spectroscopy and constant temperature capacitance transient techniques. The capture behavior of these centers has been studied in detail and found to be consistent with the multiphonon emission theory. The pressure coefficients of the ionization energy and the barrier height are consistent with the large lattice relaxation model proposed by D. V. Lang and R. A. Logan [Phys. Rev. Lett. 39, 635 (1977)].
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.98437
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 6
    Digitale Medien
    Digitale Medien
    New mechanism for Si incorporation in GaAs-on-Si heteroepitaxial layers grown by metalorganic chemical vapor deposition (1989)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 55 (1989), S. 1674-1676 
    Details
    ISSN: 1077-3118
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: A new mechanism is proposed for Si incorporation in GaAs-on-Si heteroepitaxial layers grown by metalorganic chemical vapor deposition. This mechanism involves gas phase transport of the Si to the heteroepitaxial layers during growth. This mode of Si uptake could operate in addition to the previously proposed mechanism of Si incorporation by enhanced diffusion from the heterointerface through defects in the GaAs layer.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.102232
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 7
    Digitale Medien
    Digitale Medien
    Structural properties of As-rich GaAs grown by molecular beam epitaxy at low temperatures (1989)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 54 (1989), S. 1881-1883 
    Details
    ISSN: 1077-3118
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: GaAs layers grown by molecular beam epitaxy (MBE) at substrate temperatures between 200 and 300 °C were studied using transmission electron microscopy (TEM), x-ray diffraction, and electron paramagnetic resonance (EPR) techniques. High-resolution TEM cross-sectional images showed a high degree of crystalline perfection of these layers. For a layer grown at 200 °C and unannealed, x-ray diffraction revealed a 0.1% increase in the lattice parameter in comparison with bulk GaAs. For the same layer, EPR detected arsenic antisite defects with a concentration as high as 5×1018 cm−3. This is the first observation of antisite defects in MBE-grown GaAs. These results are related to off-stoichiometric, strongly As-rich growth, possible only at such low temperatures. These findings are of relevance to the specific electrical properties of low-temperature MBE-grown GaAs layers.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.101229
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 8
    Digitale Medien
    Digitale Medien
    Pressure dependence of the DX center in Ga1−xAlxAs:Te in the vicinity of the Γ-X crossover (1988)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 53 (1988), S. 1195-1197 
    Details
    ISSN: 1077-3118
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: The pressure dependence of the DX center in Ga1−xAlxAs :Te has been studied in two samples with x=0.15 and 0.35, respectively. The pressure coefficients of the activation energies for both emission and capture were found to change sign when the band gap of GaAlAs changes from direct to indirect. These results, together with previous experiments, suggested that electrons can be emitted from and capture into the DX centers via both L and X valleys.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.100017
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 9
    Digitale Medien
    Digitale Medien
    Decoration of flux pinning positions in YBa2Cu3O7−δ superconductors (1988)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 52 (1988), S. 326-327 
    Details
    ISSN: 1077-3118
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: Flux pinning in the sintered high Tc oxide superconductors, YBa2Cu3O7−δ, in the vortex state has been demonstrated for the first time using the Bitter pattern technique and scanning electron microscopy. External magnetic fields of 150 or 800 G perpendicular to the specimen surfaces were applied during the evaporation of cobalt after the specimens cooled with liquid nitrogen had reached a temperature below Tc. All specimens thus decorated with cobalt show nonuniformly distributed flux pinning positions as would be expected due to the porosity and multiphase character of the specimens as well as the relatively low field applied.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.99650
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 10
    Digitale Medien
    Digitale Medien
    Device quality growth and characterization of (110) GaAs grown by molecular beam epitaxy (1987)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 51 (1987), S. 670-672 
    Details
    ISSN: 1077-3118
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: Device quality (110)GaAs has been reproducibly grown by molecular beam epitaxy (MBE) for the first time. Angling of the substrate to expose stable, Ga-rich ledges on the (110) surface has been shown to be the necessary condition for two-dimensional growth. The layers exhibit a room-temperature electron mobility of ∼5700 cm2/V s for NSi∼4×1015 and a strong exciton photoluminescence emission at 4 K. This breakthrough in MBE growth of III-V compounds allows for fabrication of (110) GaAs devices which will take advantage of the unique properties of this orientation.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.98329
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...