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
    A high-temperature pulsed supersonic nozzle (1993)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 64 (1993), S. 3020-3021 
    Details
    ISSN: 1089-7623
    Quelle: AIP Digital Archive
    Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik
    Notizen: A pulsed supersonic nozzle is presented which can be heated to 1300 K and cooled to 4 K. The whole system is composed of quartz to prevent the decomposition of the molecules at a high temperature. The nozzle has produced gas pulses at a rate of 10 Hz and pulse lengths of 5 ms. The performance of the system is demonstrated by the flight time and the rotational temperature of NO molecules as a function of the stagnation pressure and the nozzle temperature.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.1144351
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 2
    Digitale Medien
    Digitale Medien
    New vapor phase spontaneous Raman spectrometer (1992)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 63 (1992), S. 3280-3284 
    Details
    ISSN: 1089-7623
    Quelle: AIP Digital Archive
    Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik
    Notizen: A highly sensitive, spontaneous Raman spectrometer designed for the study of vapors and other low-density samples is discussed. The high sensitivity is achieved by means of the novel combination of a multipass light cell and a high-temperature gasdynamic focusing system. A complete description of the apparatus is given, along with the results of a sensitivity test in ambient air, as well as results demonstrating gasdynamic focusing of a vapor and Raman transitions in such a sample.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.1142537
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 3
    Digitale Medien
    Digitale Medien
    An electron diffraction study of alkali bromide vapors (1987)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 87 (1987), S. 5477-5482 
    Details
    ISSN: 1089-7690
    Quelle: AIP Digital Archive
    Thema: Physik , Chemie und Pharmazie
    Notizen: The structures of NaBr, KBr, RbBr, and CsBr in the vapor phase were determined via standard electron diffraction counting techniques with nozzle temperatures ranging from 820–920 K. The data analysis yielded the structure parameters and the ratio of the monomeric to dimeric compounds. The mean amplitudes of vibration for the monomeric molecules were held at values based on microwave frequencies and the harmonic potential approximations. The corrected monomer distances re agree well with microwave–spectroscopy results. Rhombic geometries with bonded dimer distances ranging from 2.74 to 3.37 A(ring) and Br–M–Br angles that ranged from 85° to 101.6° were observed. The percentage of dimer in the vapor was found to vary from 7% to 18%. The most surprising result was the large value obtained for the KBr dimer bonded distance. It is substantially larger than predicted by current theories and is nearly as large as the interionic distance in the crystal. Thermodynamic calculations were performed to allow comparisons of the dimer mole fractions observed with values derived from existing structure models.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.453666
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 4
    Digitale Medien
    Digitale Medien
    New elastic electron scattering factors for the elements for incident energies of 10, 40, 60, and 90 keV (1986)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 85 (1986), S. 6810-6811 
    Details
    ISSN: 1089-7690
    Quelle: AIP Digital Archive
    Thema: Physik , Chemie und Pharmazie
    Notizen: An improved set of scattering factors for all neutral elements has bee completed for inclusion in the new edition of the International Tables of X−ray Crystallography . These calculations are compared with the former electron scattering factors and the deviations between the two are discussed.(AIP)
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.451417
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 5
    Digitale Medien
    Digitale Medien
    An electron diffraction study of alkali chloride vapors (1985)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 83 (1985), S. 4418-4426 
    Details
    ISSN: 1089-7690
    Quelle: AIP Digital Archive
    Thema: Physik , Chemie und Pharmazie
    Notizen: Monomers and dimers of the four alkali chlorides NaCl, KCl, RbCl, and CsCl have been studied in the vapor phase using the counting method of high energy electron diffraction. Nozzle temperatures from 840–960 K were required to achieve the necessary vapor pressures of approximately 0.01 Torr. Large mean amplitudes of vibration (as big as 0.26 A(ring)) and the similarity of the monomer and dimer bonded distances complicate the analysis, although the refined structures yield good fits to the data, especially for the stronger scatterers RbCl and CsCl. Using harmonic calculations for the monomer and dimer l values, a consistent set of structures for all four molecules is obtained. The corrected monomer re distances reproduce the microwave values very well. The planar rhombic structure of the dimers shows a uniform decrease of the Cl–M–Cl angle as the alkali M increases in size. For the better data sets some of the l values were refined to gain perspective on the validity of the calculated ones. The experiment also yields information on the amount of dimer present in the vapor, and these results are compared with thermodynamic values.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.449060
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 6
    Digitale Medien
    Digitale Medien
    A pulsed supersonic molecular beam with high rotational temperatures (1994)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 65 (1994), S. 407-411 
    Details
    ISSN: 1089-7623
    Quelle: AIP Digital Archive
    Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik
    Notizen: The construction and operation of a novel high temperature pulsed quartz nozzle employed for the generation of rotationally excited supersonic molecular beams are reported herein. At high stagnation pressures ((approximately-greater-than) 1 bar) the NO molecules in the beam pulse exhibit a translational and rotational behavior identical to heated continuous nozzles (Trot〈50 K; Ekin≈7/2 kTN). At reduced stagnation pressures (10 mbar–1 bar) the rotational temperatures of the beam molecules are increased substantially (up to Trot≈700 K) accompanied by a translational behavior, which can be characterized by a small Mach number. The design has produced the rotationally hottest supersonic beam ever prepared in the pulsed mode.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.1145147
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 7
    Digitale Medien
    Digitale Medien
    Vortex dynamics investigation using an acoustic technique (1999)
    [S.l.] : American Institute of Physics (AIP)
    Physics of Fluids 11 (1999), S. 3380-3389 
    Details
    ISSN: 1089-7666
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: A new acoustic technique using the double time-reversal mirrors system and based on geometrical acoustics, is used to study a vortical flow. The interaction between the sound and a vortex is described in details. This technique has been applied to the study of a stretched vortex. This vortex is generated by stretching the vorticity of a boundary layer in a low velocity water channel. It is shown that the velocity field can be reconstructed from the phase distortion of an ultrasonic wave. The technique gives access to a complete characterization of the vortex dynamics, such as the temporal evolution of its size, its circulation and its position. © 1999 American Institute of Physics.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.870197
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 8
    Digitale Medien
    Digitale Medien
    Investigating a stretched vortex with ultrafast two-dimensional ultrasonic speckle velocimetry (2001)
    [S.l.] : American Institute of Physics (AIP)
    Physics of Fluids 13 (2001), S. 1683-1690 
    Details
    ISSN: 1089-7666
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: Ultrasonic speckle velocimetry (USV) was recently introduced as a new ultrafast tool for measuring fluid velocities in two dimensions by analyzing the speckle signal backscattered from particles moving with the flow [Sandrin et al., Appl. Phys. Lett. 78, 1155 (2001)]. An experimental study of a stationary stretched vortex is presented, which demonstrates the efficiency of ultrafast 2D USV in terms of quantitative assessment of vortical flows. The full velocity field is recovered and compared to the Burgers model for two different fluids: water and milk. The dependence of the vortex characteristics on the main control parameter is investigated. © 2001 American Institute of Physics.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.1370388
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 9
    Digitale Medien
    Digitale Medien
    Structure of zinc phthalocyanine by gas phase electron diffraction (1993)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 99 (1993), S. 6416-6420 
    Details
    ISSN: 1089-7690
    Quelle: AIP Digital Archive
    Thema: Physik , Chemie und Pharmazie
    Notizen: Gas phase electron diffraction data have been successfully recorded for zinc phthalocyanine. Molecular structure parameters have been determined by least square fitting a geometrically consistent model of C4v symmetry to the data. The results agree well with previous x-ray diffraction studies of crystals. However, the zinc atom was found to be slightly out the plane of the molecule in contrast with the x-ray results.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.465880
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 10
    Digitale Medien
    Digitale Medien
    An electron diffraction study of alkali fluoride vapors (1988)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 89 (1988), S. 6058-6063 
    Details
    ISSN: 1089-7690
    Quelle: AIP Digital Archive
    Thema: Physik , Chemie und Pharmazie
    Notizen: The structures of NaF, KF, RbF, and CsF in the vapor phase were determined via standard electron diffraction counting techniques with nozzle temperatures ranging from 798 to 1123 K. The reactivity of the fluorides combined with the higher temperature requirements necessitated a new nozzle design as well as modification to the oven. The data analysis yielded the structure parameters and the ratio of monomeric to dimeric compounds. The mean amplitudes of vibration of the monomeric molecules were held at values based on microwave frequencies and the harmonic potential approximation. The corrected monomer distances re agree well with microwave-spectroscopy results. Rhombic geometries with bonded dimer distances ranging from 2.08 to 2.70 A(ring) were observed. The F–M–F bond angles were found to be nearly constant, varying only from 82.2° to 85.5°. The dimer mole fractions in the vapor were observed to vary from 5% to 18%. There were no significant amounts of any trimeric species observed in the vapor. The observed dimer mole fractions were compared with existing measurements from velocity selection experiments and found to be in excellent agreement. The dimer mole fractions were also compared with various theoretical predictions.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.455420
    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...