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
  • American Institute of Physics (AIP)  (20)
  • Springer Nature  (7)
  • American Association for the Advancement of Science (AAAS)  (4)
  • 1985-1989  (31)
Collection
Keywords
Publisher
Years
Year
  • 1
    Electronic Resource
    Electronic Resource
    The kinetics of CO dissociation on Ru(001): Time-resolved vibrational spectroscopy at elevated pressures (1989)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 90 (1989), S. 2816-2823 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Time-resolved Fourier transform-infrared reflection absorption spectroscopy (FT-IRAS) has been utilized to measure the kinetics of CO dissociation on a Ru(001) surface at elevated pressures (10−3 to 10 Torr) and temperatures (500–700 K). The reaction of CO with Ru(001) is found to be a nonsteady state and results in CO disproportionation, i.e., 2CO→C+CO2. The decrease in total CO coverage follows first order kinetics and exhibits Arrhenius behavior with an activation energy of 20.6 kcal and a preexponential factor of 102 s−1. Comparison of the overall reaction rate with that of CO2 formation (O+CO→CO2) confirms that CO dissociation is the rate-limiting step in the disproportionation reaction. The in situ reaction rate constant exhibits a weak dependence on CO pressure (〈first order). However, the determination of local CO coverages during reaction reveals a linear dependence of the dissociation rate with CO coverage. This confirms that the chemisorbed state of the molecule is a precursor to dissociation and that a high pressure is required to maintain a steady state surface coverage of CO at reaction temperature. In situ vibrational spectra demonstrate the formation of carbon islands under reaction conditions which prevent further CO adsorption and result in a decrease in total CO coverage at constant local CO coverage. Post-reaction spectroscopy confirms the formation of two-dimensional islands of carbon whose reactivity toward oxidation is found to be between that of amorphous carbon and three-dimensional graphite.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.455931
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    A potentially size-consistent multiconfiguration based coupled electron pair approximation (1989)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 90 (1989), S. 3671-3679 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: A coupled electron pair approximation is derived and illustrative calculations are presented. The present approximation, which we refer to as the unitary coupled electron pair approximation (UCEPA), provides multiconfigurational (MC) reference capability and is as computationally tractable as multireference configuration interaction (MRCI). The method is capable of yielding size-consistent energies if the MC reference function is of the complete active space (CAS) variety. The coefficient matrix of the resultant set of simultaneous linear equations is evaluated using internal/external orbital space partitioning within a unitary group approach (UGA) treatment of the state space. We demonstrate the accuracy of the method on several small benchmark molecules for which full CI results are known, and on nontrivial studies on the singlet–triplet splitting in methylene and the electron affinity of the oxygen atom.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.455824
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Vibrational phase relaxation at surfaces: The role of lateral interaction (1988)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 88 (1988), S. 3349-3352 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: We have studied the temperature and coverage dependence of the vibrational line shape of the C–O stretch vibration for CO on Ru(001). We find that the narrow IR line profile which is observed for the ordered structure of CO on Ru(001) is due to the strong dipole–dipole coupling and that for low CO coverage (or in the isotopic dilution limit), where the lateral interaction is effectively zero, the linewidth of the C–O stretch mode increases in accordance with theory. The implication of this result is briefly discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.453929
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Model experiments describing the microcontact of ZnO varistors (1985)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 57 (1985), S. 5372-5379 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: A macroscopic model of the microcontacts in ceramic ZnO varistors was prepared by using ZnO single-crystal plates and a layer of the usual oxide additives. The electrical properties of these model contacts are very similar to those of the microcontacts. Measurements on one-sided macrocontacts require the assumption of a "buried'' potential barrier underneath the surface of the ZnO, the formation of which is explained by the distribution of the atomic defects and the dopants in the ZnO. Based on this idea, the I-V characteristics in the prebreakdown region and the breakdown voltage have been calculated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.334858
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Heavy-ion excitation of rare-gas excimers (1987)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 62 (1987), S. 357-361 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Beams of high-energy heavy ions (Ar and U) from the UNILAC accelerator have been used to excite rare gases at pressures near 1 bar. The dominant spectroscopic feature observed in Ar, Kr, and Xe gases was molecular excimer emission at the second excimer continuum at 130, 150, and 170 nm, respectively. The excimer radiation was studied as a function of time (with respect to the excitation pulse), ion-beam current, pressure, and excitation density. The efficiency of excimer production from heavy-ion-beam energy was found to be several percent. Details of spectral shape, especially the ratio of first-to-second continuum emission, were found to depend on pressure and exciting beam type.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.339804
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Intrinsically irreversible light-driven engine (1985)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 58 (1985), S. 2893-2901 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We examine a reciprocating heat engine which necessarily operates far from equilibrium and about an unstable steady state. The piston of the engine is driven by the nonlinear coupling of the working fluid to an external light source which provides high quality heat and to the environment into which waste heat is dumped. We determine the piston trajectories that optimize two different criteria of process performance, the maximization of work output, and the minimization of entropy production. The trajectories optimizing different performance goals are qualitatively different. In engines not dominated by friction losses, the cycle optimizing work output requires that the expansion stroke begins with a slight compression and the temperature of the working fluid increases briefly.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.336281
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Optimal paths for thermodynamic systems: The ideal diesel cycle (1985)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 58 (1985), S. 2125-2134 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Optimal control theory is used to determine the piston trajectory which yields maximum power output for a model which incorporates the diesel engine's major irreversibilities. Optimal trajectories were obtained for the cases of unconstrained and constrained piston acceleration. Optimizing the path for our standard engine increased both the net work output per cycle and the net efficiency by about 10%.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.335977
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Oxidation of indium in gold-indium alloys (1985)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 58 (1985), S. 3200-3205 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The oxidation in air of AuIn alloys with low indium content (1 ppm, 0.1 and 1.0 at. %) was investigated with the help of the time-differential perturbed angular correlation technique. From the results it is concluded that the oxidation is external and is independent of solute concentration. While in the concentrated alloys, the oxide formed was In2O3, in the cases of the dilute ones, In-O-Au complexes appeared. From the oxidation rate in the temperature range 300–1000 °C values of the frequency factor A=0.006(10) cm2/s and the activation energy Q=29.0(5) kcal/mol for the diffusion of indium in gold were obtained.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.335829
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Instrument to collect fogwater for chemical analysis (1985)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 56 (1985), S. 1291-1293 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: An instrument is presented which collects large samples of ambient fogwater by impaction of droplets on a screen. The collection efficiency of the instrument is determined as a function of droplet size, and it is shown that fog droplets in the range 3–100-μm diameter are efficiently collected. No significant evaporation or condensation occurs at any stage of the collection process. Field testing indicates that samples collected are representative of the ambient fogwater. The instrument may easily be automated, and is suitable for use in routine air quality monitoring programs.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1137995
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Photoelastic modulator for the mid-IR range down to 33 μm with inexpensive and simple control electronics (1987)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 58 (1987), S. 1675-1677 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: The construction of a photoelastic modulator is described which is intended to push the long wavelength limit of infrared circular dichroism measurements down to about 300 cm−1 (33 μm). A simple electronic circuit has been designed to drive the device. The performance of the modulator is evaluated by transmission and calibration spectra.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1139656
    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...