Bibliothek

X
Ihre Suchhistorie ist leer.
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
    Experimental measurements and numerical simulations of the gas composition in a hot-filament-assisted diamond chemical-vapor-deposition reactor (1994)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 76 (1994), S. 7567-7577 
    Details
    ISSN: 1089-7550
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: Molecular-beam mass spectroscopy was used to measure the gas composition near a growing diamond surface in a hot-filament-assisted chemical-vapor-deposition reactor. The dependencies of the gas composition on changes in (1) the carbon mole fraction in the reactor feed XC, (2) the identity of the inlet carbon source (CH4 versus C2H2), and (3) the surface temperature TS, were studied. For XC≤0.02, the gas composition appeared to be nearly independent of the identity of the inlet hydrocarbon source and depended only on the C/H ratio in the feed gas. At higher values of XC, catalytic poisoning of the hot filament resulted in different product distributions in these two systems. Increasing the surface temperature affected changes in the hydrocarbon composition; the dependencies of the CH3 and C2H2 mole fractions on TS can each be characterized as having an activation energy of 3±1 kcal/mol. Surprisingly, the H-atom mole fraction was independent of TS. These results suggest that reported temperature sensitivities of film growth properties are primarily due to changes in the kinetics of surface processes rather than changes in the gas composition near the surface. A numerical model of the process is presented. In the study of the compositional change as a function of XC, the code gives good prediction for the methane case but grossly underestimates the methane and methyl concentrations for the acetylene case. The H-atom mole fraction is predicted to increase by ×7 if the H destruction probability on the diamond surface is expected to have an activation energy of 7.3 kcal/mol. Good agreement with experimental data can be obtained, however, if H loss by lateral transport to the walls is taken into account. © 1994 American Institute of Physics.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.358525
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 2
    Digitale Medien
    Digitale Medien
    Optical and electrical properties of direct-current magnetron sputtered ZnO:Al films (2001)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 90 (2001), S. 3432-3436 
    Details
    ISSN: 1089-7550
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: In this study, high-quality ZnO:Al (ZAO) films were prepared by using dc reaction magnetron sputtering technology. The effect of Al doped in ZnO films on electrical and optical properties and its scattering mechanism were discussed in detail. The results showed that Al2O3 could be effectively removed by controlling oxygen flow and Al-doped concentration during deposition of ZnO:Al films. Zn, Al, and oxygen elements were well distributed through the films. For highly degenerated ZnO:Al semiconductor thin films, it was revealed that ionized impurity scattering dominated the Hall mobility of the films in the low-temperature range; while the lattice vibration became a major scattering mechanism in the high-temperature range. The grain-boundary scattering only played a major role in the ZAO films with small grain size (as compared to the electron mean-free path). The photoelectric properties of ZAO films showed that the lower resistivity (∼5×10−4 Ω cm) was obtained, and transmittance in the visible range and reflectance in the IR region were above 80% and 60%, respectively. © 2001 American Institute of Physics.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.1398070
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 3
    Digitale Medien
    Digitale Medien
    Gas-phase kinetics during microwave plasma-assisted diamond deposition: Is the hydrocarbon product distribution dictated by neutral-neutral interactions? (1992)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 72 (1992), S. 3102-3109 
    Details
    ISSN: 1089-7550
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: The mole fractions of H, H2, CH3, CH4, and C2H2 that were generated in a microwave plasma under conditions typical for diamond deposition are reported. When the methane percentage in the feed gas was 〈1%, the measured concentrations were surprisingly similar to those reported for a hot-filament system operated under nearly identical conditions. However, as the methane percentage was increased beyond 1%, a noticeable deviation from the hot-filament results became apparent. In the hot-filament case, surface-induced dissociation of hydrogen on the filament surface was significantly inhibited at this high methane level and lead to a pronounced reduction of the H-atom concentration. But, in the microwave system where dissociation is a homogeneous process, no such reduction was observed. Other observations were: (i) The acetylene concentration scaled as the square of the methyl concentration; (ii) The CH4+H↔CH3+H2 reaction was found to be at the same level of nonequilibrium as in the hot-filament case. These results, plus arguments based on general principles of plasma chemistry, are taken as indications that the hydrocarbon chemistry in the microwave system is as strongly dictated by neutral-neutral reactions as in a thermal system. The primary effect of the plasma is perhaps its role in dissociating hydrogen molecules to H atoms without having to raise the gas temperature significantly.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.351470
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 4
    Digitale Medien
    Digitale Medien
    Diamond deposition from fluorinated precursors using microwave-plasma chemical vapor deposition (1995)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 67 (1995), S. 2379-2381 
    Details
    ISSN: 1077-3118
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: Diamond thin films were grown using fluorinated precursors by microwave plasma-assisted chemical vapor deposition. Using CH4/H2, CH3F/H2, and CF4/H2 gas mixtures, films were grown at surface temperatures in the range 600–900 °C at constant microwave power, carbon mole fraction, and pressure. Growth activation energies for the CH4/H2, CH3F/H2, and CF4/H2 mixtures were 12.6±1.8, 13.7±1.2, and 12.4±1.1 kcal/mole, respectively. Argon ion etching in conjunction with x-ray photoelectron spectroscopy indicated negligible fluorine incorporation into the films. These results are consistent with the hypothesis that diamond is grown from the same intermediates, namely methyl radicals and atomic hydrogen, for all of these mixtures. © 1995 American Institute of Physics.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.114351
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 5
    Digitale Medien
    Digitale Medien
    In-situ monitoring of redeposited carbon in the vicinity of a plasma–graphite interacting region (abstract) (1988)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 59 (1988), S. 1891-1891 
    Details
    ISSN: 1089-7623
    Quelle: AIP Digital Archive
    Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik
    Notizen: The interaction of the plasma with graphite limiters in fusion devices has been observed to lead to the formation of carbon film deposits. This occurs from the erosion of the graphite tiles in a high-flux region and subsequent redeposition of the carbon atoms onto a low-flux surface. The redeposition of carbon has strong ramifications on the in-vessel tritium inventory. A commercially available quartz crystal monitor has been tested in a plasma simulator device to measure the flux of eroded carbon. The test was done with the intent of mounting such a detector in TFTR. The monitor measures the deposited film thickness as a change in the resonance frequency of the crystal. The plasma simulator is a Penning discharge operated with graphite electrodes. Initial tests show the crystal monitor has high sensitivity and can detect film thickness changes of a few angstroms. Thermal shock problems, however, may limit time resolution of the measurement and can provide only an integrated deposited thickness within a discharge. This work was supported by the U. S. DOE.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.1140046
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 6
    Digitale Medien
    Digitale Medien
    Oscillatory magnetic interlayer exchange coupling in Fe–N/TiN multilayers (1996)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 68 (1996), S. 2887-2889 
    Details
    ISSN: 1077-3118
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: The discovery of oscillatory interlayer exchange coupling in a new type of ceramic superlattice system Fe–N/TiN, is reported. The magnitude of the exchange coupling was found to oscillate with the thickness of the TiN spacer layer and Fe–N ferromagnetic layer with periods about 0.8 and 0.6 nm, respectively. © 1996 American Institute of Physics.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.116321
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 7
    Digitale Medien
    Digitale Medien
    Phenolic Composition of Authentic Pineapple Juice (2002)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of food science 67 (2002), S. 0 
    Details
    ISSN: 1750-3841
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft , Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: : The phenolic composition of authentic pineapple juice concentrate was analyzed by HPLC. Nine major peaks accounting for 70% of total peak area were characterized and their concentrations measured in 54 commercial samples. Means and standard deviations were as follows (mg/100 mL single-strength juice, normalized to 12.8 °Brix): tyrosine, 3.6(1.4); serotonin, 1.8(0.8); dimethylhydroxylfuranone, 1.4(0.7); dimethylhydroxylfuranone β-glucoside, 6.2(3.0); tryptophan, 2.2(0.9); S-sinapyl-L-cysteine, 1.1(0.6); N-γ-L-glutamyl-S-sinapyl-L-cysteine, 2.3(1.1); S-sinapyl glutathione, 5.4(1.4); and a p-coumaric acid-like phenolic compound (calculated as p-coumaric acid), 0.5(0.4). This information will be useful for evaluation of authenticity and quality.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1111/j.1365-2621.2002.tb11376.x
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 8
    Digitale Medien
    Digitale Medien
    Total amino acid analysis using pre-column fluorescence derivatization
    Amsterdam : Elsevier
    Journal of Chromatography A 239 (1982), S. 463-474 
    Details
    ISSN: 0021-9673
    Quelle: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Thema: Chemie und Pharmazie
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1016/S0021-9673(00)82003-8
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 9
    Digitale Medien
    Digitale Medien
    Purification of high mobility group nonhistone chromosomal proteins by liquid chromatography ona column containing immobilized histone H5
    Amsterdam : Elsevier
    Journal of Chromatography A 314 (1984), S. 436-444 
    Details
    ISSN: 0021-9673
    Quelle: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Thema: Chemie und Pharmazie
    Materialart: Digitale Medien
    URL: http://linkinghub.elsevier.com/retrieve/pii/S0021-9673(01)97758-1
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 10
    Digitale Medien
    Digitale Medien
    Heterogeneity in cDNA clones encoding rice glutelin
    Amsterdam : Elsevier
    FEBS Letters 222 (1987), S. 135-138 
    Details
    ISSN: 0014-5793
    Schlagwort(e): (Rice) ; Amino acid sequence ; Glutelin ; Nucleotide sequence ; cDNA clone
    Quelle: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Thema: Biologie , Chemie und Pharmazie , Physik
    Materialart: Digitale Medien
    URL: http://linkinghub.elsevier.com/retrieve/pii/0014-5793(87)80206-5
    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...