ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

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
    Springer
    International journal of thermophysics 14 (1993), S. 923-936 
    ISSN: 1572-9567
    Keywords: alkali halides ; correlation ; corresponding states ; molten salts ; thermal conductivity ; thermal diffusivity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The principle of corresponding states has been applied to the thermal-conductivity data for molten alkali halides which have been obtained by recent forced Rayleigh scattering measurements. The theory, which was developed by Harada et al. for the transport properties of uni-univalent molten salts, is based on the fluctuation-dissipation theorem with the pair interaction between ions composed of core repulsive and Coulombic potentials. Four characteristic parameters specific to each salt have been used to reduce the thermal conductivity and temperature. It has been found that the thermal conductivity of molten alkali halides is adequately correlated by the corresponding-states correlation (λ * ∝ 1/T *) within experimental accuracy. By employing the correlation, the thermal conductivity of molten alkali fluorides, which could not be measured by the forced Rayleigh scattering method, is predicted.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    International journal of thermophysics 13 (1992), S. 931-942 
    ISSN: 1572-9567
    Keywords: capillary viscometer ; HFC 134a ; 1, 1, 1, 2-tetrafluoroethane ; viscosity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The viscosity of HFC 134a was measured over the range of temperatures from 213 to 423 K and pressures up to 30 MPa. The experimental method was that of the capillary flow and a closed-circuit high-pressure viscometer was used. The sample fluid was circulated through a stainless-steel capillary from a highpressure plunger system. The constant of the capillary was calibrated against the reference standard, pure water. The viscosity of the sample was calculated from the flow rate, the pressure drop at the capillary, and the capillary constant using the Hagen-Poiseuille equation. Measurements were made at a total of 39 points on eight isotherms. The measurement uncertainty of the viscosities was estimated as ±1.3%. Based on the present results, an empirical equation for the viscosity of HFC 134a has been correlated. The viscosity on the saturation line calculated by the equation compares with experimental viscosity data in other previous studies. There are rather considerable differences among these measurements. Comparisons of the data for HFC 134a with those for CFC 12 show that the viscosity of HFC 134a is similar in magnitude to that of CFC 12 at temperatures around 300 K but is higher at lower temperatures and lower at higher temperatures. The pressure gradients for these two corresponding substances are similar over the entire temperature range.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Springer
    International journal of thermophysics 13 (1992), S. 401-410 
    ISSN: 1572-9567
    Keywords: capillary viscometer ; 1,1-dichloro-2,2,2-trifluoroethane ; HCFC 123 ; viscosity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The viscosity of HCFC 123 was measured over the range of temperature from 223 to 418 K and pressure up to 20 MPa. The experimental method was that of the capillary flow and a closed-circuit high-pressure viscometer was used. The sample fluid was circulated through a Pyrex glass capillary from a high-pressure plunger system. The constant of the Pyrex glass capillary was calibrated against the reference standard, pure water. The viscosity of the sample was calculated from the flow rate, the pressure drop at the capillary, and the capillary constant using the Hagen-Poiseuille equation. Measurements were made on seven isotherms. In the case of the transpiration method, the density is needed for calculation of the viscosity from the kinematic viscosity. The available density data of HCFC 123 are less reliable than those for CFC 11. Therefore, uncertainty in the viscosity of HCFC 123 is larger, although the measured kinematic viscosity itself has a reproducibility of 0.1 %. HCFC 123 is proposed as an alternative to CFC 11. Comparisons of the data for these two substances show that the viscosity of HCFC 123 is similar in magnitude to that of CFC 11 at temperatures around 350 K, higher at lower temperatures, and lower at higher temperatures. The pressure gradients for these two corresponding substances are similar over the entire temperature range.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1572-9567
    Keywords: alkali halides ; forced Rayleigh scattering method ; molten salts ; thermal conductivity ; thermal diffusivity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract This paper is an addendum to two previous papers which contained data on the thermal diffusivity of molten alkali metal chlorides and bromides. The present salts are alkali metal iodides: NaI, KI, RbI, and CsI. The measurements were performed utilizing the forced Rayleigh scattering method at temperatures up to 1234 K. The accuracy of the reported data is estimated to be ±5 to ±10%. It is again found that our data show one of the smallest values and weakly negative temperature dependencies.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 1572-9567
    Keywords: alkali halides ; forced Rayleigh scattering method ; molten salts ; thermal conductivity ; thermal diffusivity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract As a series of experimental determinations of the thermal diffusivity of molten alkali halides, this paper describes measurements on five molten alkali metal chlorides (LiCl, NaCl, KCl, RbCl, and CsCl) in the temperature range up to 1440 K by the forced Rayleigh scattering method. K2Cr2O7 is employed as a dye substance to color the transparent molten salts. The accuracy is estimated to be ± 4 to ±11 % depending on the measured salts. In comparison with the present results converted into thermal conductivity, most of the previous experimental data obtained by steady-state methods show larger values, up to about five times, which may be due to the systematic error caused by the presence of convection and radiation. It is found that the thermal conductivity of these series of molten alkali metal chlorides decreases with increasing molecular weight, and their temperature coefficients are weakly negative.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1572-9567
    Keywords: alkali halides ; forced Rayleigh scattering method ; molten salts ; thermal conductivity ; thermal diffusivity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract This is a companion to an earlier paper (on molten alkali metal chlorides) which gives experimental results for the thermal diffusivity of four molten alkali metal bromides: NaBr, KBr, RbBr, and CsBr. The measurements were performed with a forced Rayleigh scattering instrument at temperatures up to 1326 K. The overall uncertainty in the measured thermal diffusivity is estimated to be ±3 to ±11%, depending on the measured salts. The results converted to thermal conductivity show one of the smallest values among other earlier experimental data obtained mainly by the steady-state methods. It is also found that the temperature dependence of the thermal conductivity is weakly negative.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...