ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

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
  • 1990-1994  (1,661)
  • 1970-1974
  • 1991  (1,661)
Collection
Keywords
Publisher
Years
  • 1990-1994  (1,661)
  • 1970-1974
Year
  • 1
    Electronic Resource
    Electronic Resource
    Hydrogenation effect on electrical and optical properties of GaAs epilayers grown on Si substrates by metalorganic chemical vapor deposition (1991)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 58 (1991), S. 2405-2407 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Hydrogenation effects on electrical and optical properties in GaAs epilayers grown on Si substrate by metalorganic chemical vapor deposition have been investigated. In as-grown GaAs layers on Si substrates, typically four deep levels at 0.81, 0.68, 0.57, and 0.53 eV below the conduction band were observed by deep level transient spectroscopy. After hydrogen plasma exposure at 250 °C for 2.5 h, the 0.68 eV level disappeared. In addition, the reverse leakage current in the hydrogenated sample decreased by three orders of magnitude compared to the untreated sample. These effects persist after dehydrogenation process with a 5 min, 400 °C anneal. The results indicate that the hydrogenation for GaAs-on-Si has some benefits to its device application.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.104885
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    A study on the Kerr effect enhancement by the multidielectric layer structure : 35th annual conference on magnetism and magnetic materials (1991)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 69 (1991), S. 5987-5988 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Many types of magneto-optical structures have been investigated to improve the MO Kerr effect. We have studied the enhancement of the MO Kerr effect in the Tb21Fe79 amorphous film having a multidielectric structure in which the TiO2 layer is sandwiched by SiNx layers. The variations of Kerr angle and reflectivity with the thickness of dielectric layer are calculated by using the reiterative formula [M. Mansuripur, G. A. N. Connel, and J. W. Goodman, J. Appl. Phys. 53, 4485 (1982)]. Experiment and simulation results are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.347813
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Optical properties of AgGaSe2 and AgGaSe2:Co2+ single crystals (1991)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 69 (1991), S. 7797-7799 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The temperature dependence of the optical energy gaps in AgGaSe2 and AgGaSe2:Co2+ single crystals has been investigated. The impurity optical absorption of AgGaSe2:Co2+ has also been studied. In the temperature dependence of the energy gaps, the temperature coefficients (dEg/dT) are measured to be 1.8×10−4 eV/K (10–60 K) and −3.2×10−4 eV/K (95–300 K) for the AgGaSe2, and 8.9×10−5 eV/K (10–60 K) and −1.0×10−4 eV/K(80–300 K) for the AgGaSe2:Co2+, respectively. In the optical-absorption spectrum of the AgGaSe2:Co2+, three absorption bands of 1.54, 0.72, and 0.51 eV are observed. It is identified that these impurity absorption peaks are attributed to the electronic transitions between the split energy levels of Co2+ ion with Td symmetry sites of the AgGaSe2 host lattice.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.347507
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Nb-added high-coercivity Nd-Fe-B melt-spun ribbon with high remanence : The 5th Joint MMM−Intermag Conference (1991)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 70 (1991), S. 6477-6479 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The effects of composition and additives on the microstructures and magnetic properties of Nd-Fe-B melt-spun ribbons were studied. Experimental results have revealed that homogeneous grain structure with fine grain size was obtained on composition close to 2-14-1 stoichiometry with additives. It was also found that Nb was very effective in increasing both remanence and coercivity in a Nd-Fe-B melt-spun ribbon. A high-energy product of 151.2 kJ/m3 (19.0 MGOe) was obtained from an isotropic (Nd0.5Pr0.5)12Fe72Co8B6Nb2 melt-spun ribbon with a remanence of 0.926 T and a coercivity exceeding 1200 kA/m (∼15 kOe).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.349905
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Effects of photochemical vapor deposition phosphorus-nitride interfacial layer on electrical characteristics of Au-InP Schottky diodes (1991)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 69 (1991), S. 6699-6700 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The enhancement of Schottky barrier heights on InP substrate using a thin layer of phosphorus-nitride(P3N5), grown by a direct photochemical vapor deposition process with a gaseous mixture of PCl3 and NH3, has been studied. A Au-Schottky diode formed using the in situ processes has a 50-A(ring) P3N5 intermediate layer showed a barrier height of 0.81 eV, an ideality factor of 1.08, and a reverse leakage current of 5.0 × 10−8 A(ring)/cm2 at 1 V. The breakdown voltage was larger than 30 V. The thin-film/InP interface was investigated using x-ray photoelectron spectroscopy.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.348972
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Hydrogen bonding between the water molecule and the hydroxyl radical (H2O⋅OH): The 2A‘ and 2A' minima (1991)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 94 (1991), S. 2057-2062 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The two degenerate components of the OH radical 2Π ground electronic state give rise to independent minima (of 2A‘ and 2A' symmetries) upon interaction with the water molecule. These two minima have been investigated here for the first time using ab initio quantum mechanical methods. Minimum, double zeta, double zeta plus polarization, and triple zeta plus double polarization basis sets have been employed in conjunction with self-consistent-field, second-order perturbation, and configuration interaction methods. At all levels of theory, the 2A‘ state is predicted to be the global minimum, with a dissociation energy De of about 3.5 kcal/mol. The 2A' state is predicted to lie about 1 kcal higher in energy. Both minima occur for structures with OH⋅⋅⋅O linkages close to linear and are reminiscent of the water dimer. However, the H⋅⋅⋅O distances (∼2.1 A(ring) for 2A‘, ∼2.2 A(ring) for 2A') are significantly longer than observed for the water dimer. Preliminary estimates of the H2O⋅OH vibrational frequencies are made.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.459927
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Fabrication of YBa2Cu3Ox superconductor using Y2BaCuO5, BaCuO2 and CuO (1991)
    Springer
    Journal of materials science 26 (1991), S. 3593-3598 
    Details
    ISSN: 1573-4803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract YBa2Cu3O x superconductor was synthesized using Y2BaCuO5, BaCuO2, and CuO powder mixture. Reaction temperatures were identified using differential thermal analysis (DTA) and thermogravimetry (TG) for syntheses of precursor powders and the powder mixtures. Appropriate reaction temperatures for Y2BaCuO5 and BaCuO2 precursor powders were 950 and 930°C, respectively. Two endothermic reactions involving melt formations were identified on the DTA and TG curves of the powder mixture, and the liquid increased the reactivity of the YBa2Cu3O x formation. Powder mixture samples were sintered at various temperatures ranging from 880 to 1000°C. Microstructural and X-ray powder diffraction studies showed YBa2Cu3O x and impurities to be formed in the samples sintered at various temperatures. The samples sintered at 990 and 1000°C showed dense microstructures. The critical temperature was 84 K for the sample sintered at 880°C and rose to 92 K as the sintering temperature increased.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00557149
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Determination of impurities in semiconductor grade silicon by instrumental neutron activation analysis (1991)
    Springer
    Journal of radioanalytical and nuclear chemistry 151 (1991), S. 373-378 
    Details
    ISSN: 1588-2780
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Energy, Environment Protection, Nuclear Power Engineering
    Notes: Abstract Instrumental neutron activation analysis has been applied to semiconductor grade silicon to study the concentration levels of impurity elements, the contamination during the single crystal growing process, and the vertical and radial distributions of impurities, along with the decontamination effect in the analysis. Twenty elements of Au, Br, As, W, Cr, Co, Na, Eu, La, Se, Zn, U, Th, Hf, Fe, Sb, Ag, Ce, Tb and Ta have been analyzed in p- and n-type wafers, single crystals and a polycrystal by a single comparator method using two comparators of gold and cobalt. Considerable surface contamination has been found and could be removed by etching the surface with nitric and hydrofluoric acid before and after irradiation. The impurity concentration has been found to be generally increased in the process of single crystal growth. The vertical and radial distributions of impurities have revealed that some impurity elements were more concentrated in the top region of a single crystal rod than in the middle region, and that Br, Cr, La, Eu and Sb were enriched in the central region and As, U and Fe in the outer region.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02035497
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Effect of drying conditions on the glass transition of poly(acrylic acid) (1991)
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 31 (1991), S. 867-872 
    Details
    ISSN: 0032-3888
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Systematic changes of drying conditions of poly(acrylic acid) were tested to study their effect on the glass transition of the material. The materials were synthesized in two different mediums of water and benzene, respectively. The glass transition temperatures of the samples were determined by thermal analysis using DSC. The samples were also characterized by IR spectra. The glass transition of poly(acrylic acid) was found to be significantly dependent on the drying conditions and also dependent on the medium in which poly(acrylic acid) was prepared. The anhydride formation in poly(acrylic acid) was increased as the drying temperature was raised, resulting in the increase of the glass transition temperature. The “bound” water involved in the preparation of poly(acrylic acid) in water medium could affect significantly the glass transition of the sample. A significant discrepancy in the previously reported values of the glass transition temperature of poly(acrylic acid) seems to be due to the differences in the drying conditions of the materials.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pen.760311205
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Crystallization characteristics of isotactic polypropylene with and without nucleating agentsParts of this paper have been presented at the IUPAC international Symposium, Seoul, Korea, June 1989. (1991)
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 31 (1991), S. 1009-1014 
    Details
    ISSN: 0032-3888
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Nucleation effects of two sorbitol derivatives on the crystallization of isotactic polypropylene (iPP) were studied by means of differential scanning calorimetry (DSC) and polarized optical microscopy (POM). A nonisothermal crystallization kinetic equation was employed to analyze the crystallization characteristics of iPP with or without the nucleating agents from DSC crystallization thermograms. The equilibrium melting temperature of iPP necessary for the kinetic study was obtained by the extrapolation method to be 209°C. The nonisothermal crystallization kinetic analysis for the unnucleated iPP at different cooling rates was possible by assuming the spherulite growth initiated simultaneously by heterogeneous and homogeneous nucleation. On the other hand, the crystallization kinetics of the nucleated iPP could be described by the heterogeneous nucleation and growth process alone. The addition of the nucleating agents up to their saturation concentrations in iPP increased the crystallization peak temperature by 17°C, and the number of effective nuclei by three orders of magnitude. A high concentration of the nucleating agents caused agglomeration of the agents to lower the number of effective nuclei.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pen.760311403
    Location Call Number Expected 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...