Library

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
    ISSN: 1432-0649
    Keywords: 68 ; 42.70 ; 42.60 ; 61.70 ; 61.50 ; 42.80 ; 29
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Journal of statistical physics 8 (1973), S. 299-307 
    ISSN: 1572-9613
    Keywords: Statistical thermodynamics of curved boundary layers ; scaled particle theory ; equation of state ; cycle equation ; fluid-solid phase transition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The thermodynamics of curved boundary layers, with the assumption that the distance between the surface of a fluid cavity and its surface of tension is a quadratic function of the cavity radius, is applied to the exact thermo-dynamic expression forG, the central function of scaled particle theory. The coefficients in the quadratic representation are determined so as to satisfyall five of the known exact conditions onG valid for cavity radii between one-half and one molecular diameter. The results of the calculation are displayed as the hard-sphere equation of state, the boundary tension associated with the surface of tension, and the distance between the cavity surface and the surface of tension. Although the hard-sphere equation of state obtained by this method using all five conditions onG is more accurate than in the case where only two or three conditions are used, the original scaled particle theory, in whichG itself was represented simply by a quadratic function of inverse powers of cavity radius, still yields the more accurate equation of state. Nevertheless, the present approach limits approximations to the distance between the cavity surface and the surface of tension, a small quantity in itself. The path to a still more improved theory remains well defined, contingent upon the discovery of additional exact conditions, and does not depend, as in the original scaled particle theory, on a form forG arrived at in a somewhat ad hoc manner.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1615-6102
    Keywords: Lilium ; Pollen tube ; Calcium gradient ; Polarity ; Protoninduced X-ray emission (PIXE) ; The Heidelberg proton microprobe
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The intracellular calcium distribution in pollen tubes ofLilium longiflorum was measured by proton-induced X-ray emission (PIXE) with the Heidelberg proton microprobe, which is a new method for biological application. Studies by electron-induced X-ray emission (EIXE) were done in comparison. Independent of the preparation technique, the pollen tubes show a tip-to-base calcium gradient. The shape of the calcium gradient and the total calcium content depend on the preparation technique. The calcium ionophore A-23187 destroys the calcium gradient and leads to a loss of most cell calcium. Chlorotetracycline (CTC) treatment increases the amount of membrane-bound calcium.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Protoplasma 139 (1987), S. 20-24 
    ISSN: 1615-6102
    Keywords: Calcium activity ; Calcium gradient ; Lilium ; Polar growth ; Pollen tube ; Quin-2 ; Microfluorimeter
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Pollen tubes ofLilium longiflorum were loaded with quin-2 to determine the cytoplasmic free calcium. Quin-2-fluorescence was detected at 500 nm with alternating excitation at 340 nm and 360 nm. The calcium2+-concentration was obtained using the intensity ratio R=I340/I360. The analysis exhibits a [Ca2+] of nearly 10−7mol·l−1 in the tip region and about 2·10−8 mol·l−1at the tube base, near the pollen grain. The data give evidence for the existence of a continuous gradient of free calcium within growing pollen tubes of various length.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Journal of statistical physics 7 (1973), S. 143-159 
    ISSN: 1572-9613
    Keywords: Statistical thermodynamics of curved boundary layers ; scaledparticle theory ; equation of state ; cycle equation ; fluid-solid phase transition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The thermodynamics of curved boundary layers is combined with scaled particle theory to determine the rigid-sphere equation of state. In particular, the boundary analog of the Gibbs-Tolman-Koenig-Buff equation is solved for a rigid-sphere fluid, using the approximation that the distance between the surface of a cavity and its surface of tension is a function of the density only (the first-order approximation). This, in conjunction with several exact conditions onG, the central function of scaled particle theory, leads to an approximate rigid-sphere fluid equation of state and a qualitatively correct rigid-sphere solid equation of state. The fluid isotherm compares favorably with previous results (2.9 % error in the fourth virial coefficient), but due to the inaccuracy of the solid isotherm, no phase transition is obtained. The theory described here is to be contrasted with previous approaches in that a less arbitrary functional form forG is assumed, and the surface of tension and cavity surface are not assumed to be coincident. The “cycle equation” of Reiss and Tully-Smith is rederived by a simpler route and shown to be correct to all orders of cavity curvature, rather than only first order as was originally thought. A new exact condition, obtained from the compressibility equation of state, is used as a boundary condition for the “cycle equation” to determine the location of the equimolecular surface. This molecular calculation compares favorably (discrepancy of 〈2 %) with a thermodynamic calculation based on the boundary analog of the Gibbs adsorption equation and indicates the accuracy and consistency of the first-order approximation.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...