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
  • 1
    Electronic Resource
    Electronic Resource
    Growth of carbon nanotubes by gas source molecular beam epitaxy (2001)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 89 (2001), S. 1973-1976 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Multiwall carbon nanotubes have been grown by gas source molecular beam epitaxy in the presence of Ni catalyst. Some nanotubes show thinner bases compared with their heads. First- and second-order Raman scattering spectra are used to study the structure of samples with different initial thicknesses of Ni layers. The second-order 2D Raman mode of carbon nanotubes shows a downshift compared with the graphite-like structure. The growth of carbon nanotubes is found to depend on the size of the metal droplets. When the initial Ni layer is either too thick or too thin, few carbon nanotubes are observed. The Raman spectra show graphite and glassy carbon structures for too thick and too thin initial Ni layer films, respectively. Only when a proper range of Ni catalyst film is used, carbon nanotubes could be found. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1337083
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Spin-state transition in La1−xSmxCoO3 perovskites (2001)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 89 (2001), S. 1331-1335 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Structural and magnetic properties of La1−xSmxCoO3 with x=0, 0.02, 0.04, 0.06, 0.08, 0.12, 0.16, and 0.2 have been systematically studied. LaCoO3 exhibits a rhombohedral structure of R3¯C symmetry. The lattice parameters decrease progressively with the incorporation of Sm, and a second orthorhombic phase of Pbnm symmetry appears for x≥0.12. The volume fraction of the orthorhombic phase is a sensitive function of the Sm content in the compounds, and increases from 16% for x=0.12 to 75% for x=0.2. Accordingly, the low-spin-to-high-spin transition of the trivalent Co ions, characterized by a steep rise of the magnetization, shifts to higher temperatures. A molecular field analysis indicates an increased energy gap, from 317 K for x=0 to 500 K for x=0.2, between the low-spin and the high-spin state, implying a stabilization of the low-spin trivalent Co ions by the presence of Sm. The enhanced compressive chemical pressure due to the introduction of Sm is suggested to be responsible for the present observations. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1336521
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Properties of fixed-position Bragg diffractors for parallel detection of x-ray spectra (1993)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 64 (1993), S. 2195-2200 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: Advantages of wavelength-dispersive spectrometers over energy-dispersive spectrometers for parallel detection of x rays are discussed and factors involved in the design of wavelength-dispersive spectrometers are reviewed. The dispersion and collection solid angle of fixed-position Bragg diffractors used for parallel detection of x rays are calculated and the properties of four such spectrometers based on singly and doubly curved diffractors are compared with the properties of scanning monochromators. It is concluded that the previously studied parallel-detection spectrometers based on Bragg diffractors are less advantageous than scanning monochromators but they may be preferred when it is necessary to detect many characteristic x-ray lines simultaneously or to avoid the use of moving parts.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1143959
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Effect of hydroquinone, dicyandiamide and encapsulated calcium carbide on urea N uptake by spring wheat, soil mineral N content and N2O emission (1998)
    Oxford, UK : Blackwell Publishing Ltd
    Soil use and management 14 (1998), S. 0 
    Details
    ISSN: 1475-2743
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract. At present about half of the N fertilizer used in China is as urea. However, recovery of urea N in crops is often limited to 30–40%. Application of urea in combination with hydroquinone plus dicyandiamide (U-HQ-DCD) gave an improved urea-N recovery and grain yield by spring wheat in a pot experiment. The apparent total urea-N recovery was 69% and 73% of this recovered N was found in the grain. The grain yield was 32% higher than in the treatment where urea was applied without inhibitors. The application of hydroquinone and dicyandiamide also resulted in a smaller soil nitrate content, which might restrict post-harvest leaching of N. Another beneficial effect of these inhibitors was that the N2O emission from the soil—plant system was reduced by 35% compared to the treatment where only urea was applied. The use of urea in combination with hydroquinone plus encapsulated calcium carbide gave smaller beneficial effects.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1475-2743.1998.tb00156.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    D-Homoannulation of 5.alpha.-pregnane-3.beta., 20.beta.-diol 3-acetate with phosphorus pentabromide (1968)
    s.l. : American Chemical Society
    The @journal of organic chemistry 33 (1968), S. 3632-3635 
    Details
    ISSN: 1520-6904
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/jo01273a061
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    D-Homoannulation of 3.beta.-acetoxy-5.alpha.-pregnan-20.beta.-o1 with some chlorinating agents (1968)
    s.l. : American Chemical Society
    The @journal of organic chemistry 33 (1968), S. 3635-3637 
    Details
    ISSN: 1520-6904
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/jo01273a062
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    1.55 μm high-power large optical cavity lasers (1991)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 59 (1991), S. 3087-3089 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: A high-power 1.55 μm large optical cavity (LOC) laser structure is successfully prepared for the first time by reasonably designing its configuration and by using a proper single step liquid phase epitaxy (LPE) so as to realize lasers with peak output power higher than 2 W per facet in pulsed operation at room temperature. The devices are also characterized by their lower threshold current ( Jth≤2.7 KA/cm2 for broad area contact structure) and high-temperature stability (T0≈130 K). At the same time they are of long-lived operation and are an ideal source of light in this spectral region.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.105797
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Two new all-organic complexes with electrical bistable states (1995)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 67 (1995), S. 2241-2242 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Two all-organic complexes, MC+TCNQ and BBDN+TCNQ, with electrical bistable states at room temperature have been discovered. The resistivity of these thin films prepared in vacuum can be transferred from high to low under a voltage of few volts. The transition time is 〈100 ns. Therefore, both materials are suitable for making write-once read-only memories. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.115116
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Effect of channel doping on the low-frequency noise in GaN/AlGaN heterostructure field-effect transistors (1999)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 75 (1999), S. 2064-2066 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We examined low-frequency noise in doped and undoped channel GaN/AlGaN/SiC heterostructure field-effect transistors with different Al content in the barrier. The observed noise spectra follow the 1/fγ law with 0.8≤γ≤1.2 for frequencies f up to 100 kHz. Our results indicate two orders of magnitude reduction in the input-referred noise spectral density in the undoped channel devices with respect to the noise density in the doped channel devices of comparable electric characteristics. Low temperature measurements reveal generation—recombination-type peaks in the spectra of the doped channel devices. Effects of the piezoelectric charges at the GaN/AlGaN interface are also discussed. © 1999 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.124917
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Magnetotransport study on the two-dimensional electron gas in AlGaN/GaN heterostructures (1998)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 73 (1998), S. 1391-1393 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We have performed magnetotransport studies on AlGaN/GaN heterostructures at low temperature and magnetic field up to 30 T. The integer quantum Hall effect is observed in two-dimensional electron gas at the AlGaN/GaN interface. From the temperature dependence of the low-field Shubnikov–de Hass oscillations, a carrier effective mass of m*=0.228me is obtained. Dingle plots of our resistivity data show inhomogeneity in the two-dimensional electron gas. Finally, we found that for electronic density as high as 5.47×1012 cm−2, only the lowest subband in the quantum well is occupied. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.121954
    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...