Library

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
  • 1
    Electronic Resource
    Electronic Resource
    Transient chaos in a closed chemical system (1991)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 94 (1991), S. 1134-1140 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Complex oscillations and even aperiodicity can exist as transient phenomena in closed chemical systems. These effects are illustrated through the analysis of a simple, isothermal chemical model based on mass action kinetics for autocatalytic feedback, involving the conversion of a reactant to a final product via three intermediate species. The use of the so-called pool chemical approximation and of pseudo-steady-state analyses for such systems is indicated and discussed, particularly with relevance to "real'' chemical situations where small perturbations due to extraneous noise are inevitably present.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.460019
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Erratum: Transient chaos in a closed chemical system [J. Chem. Phys. 94, 1134 (1991)] (1991)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 95 (1991), S. 2227-2227 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.461836
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Determination of approximate lumping schemes by a singular perturbation method (1993)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 99 (1993), S. 3562-3574 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: A singular perturbation method is employed for the determination of an approximate nonlinear lumped model for a chemical kinetic system described by a set of first order ordinary differential equations with a group of small positive parameters corresponding to different time scales. New variables, called purely fast variables, are introduced and determined. Substituting their explicit expressions into the original kinetic equation system yields a lumped differential equation system containing the independent variable t. The lumped system can reach any desired accuracy for any initial composition. A further approximation to this lumped system, obtained by omitting transient exponential functions of t, is shown to define the dynamics of the system on a slow invariant manifold. Two simple examples are used to illustrate this approach.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.466153
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Reduced Mechanisms for Propane Pyrolysis (1995)
    s.l. : American Chemical Society
    Industrial & engineering chemistry research 34 (1995), S. 3749-3760 
    Details
    ISSN: 1520-5045
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/ie00038a010
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    A general analysis of approximate nonlinear lumping in chemical kinetics. I. Unconstrained lumping (1994)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 101 (1994), S. 1172-1187 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: A general analysis of approximate nonlinear lumping for a chemical kinetic system described by an n-dimensional first order ordinary differential equation system dy/dt=f(y) is presented. There is a one-to-one relation between the differential equation system and the linear partial differential operator A=∑ni=1fi(y)(∂/∂yi). The algebraic method in nonlinear perturbation theory is utilized to approximately transform A into some canonical forms in which the new dependent variables are partly separated. These canonical forms of A will give the generalized eigenfunctions or other higher dimensional unconstrained nonlinear lumping schemes of the original system approximately. Unconstrained nonlinear lumping gives a reduced differential equation system describing new variables which are nonlinear functions of the original ones. This approach may supply some purely fast variables. The solutions of original dependent variables can be obtained by the inverse transformation from the lumped variables and the approximate analytical solutions of the purely fast variables. The theoretical basis of this approach is presented. A simple example is used for illustration.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.467811
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    A general analysis of approximate nonlinear lumping in chemical kinetics. II. Constrained lumping (1994)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 101 (1994), S. 1188-1201 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: A general analysis of approximate constrained nonlinear lumping is presented for a chemical kinetic system described by an n-dimensional set of first order ordinary differential equations dy/dt=f(y). There is a one-to-one relation between the differential equation system and the linear partial differential operator A=∑ni=1fi(y)(∂/∂yi). The algebraic method in nonlinear perturbation theory for lumping is extended to include constrained nonlinear lumping, in which the operator A is only transformed to a partially canonical form and some variables are left unlumped. A singular perturbation method is used to provide approximate analytical expressions for the solutions of the lumped variables. The resulting expressions can then be substituted into the equations describing the unlumped species, leading to a low dimensional system. The method is illustrated by application to a simple model describing the nonisothermal oxidation of hydrogen in a closed vessel. The results show that the method of constrained lumping leads to an accurate representation of the ignition features and maximum temperature rise given by the full model. The singular perturbation technique is proved to be only a special case of a general constrained lumping approach based on the algebraic method in nonlinear perturbation theory when the equations are linear in the deleted variables. Consequently the quasisteady-state approximation (QSSA) is the zeroth order approximation within the slow invariant manifold of the constrained approach. In cases where QSSA is not a good approximation, the first order correction generally provides significant improvement of the results.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.467812
    Library Location Call Number Volume/Issue/Year 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...