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
    Book
    Book
    Berlin :Konrad-Zuse-Zentrum für Informationstechnik,
    Title: Homoclinic Bifurcation at Resonant Eigen-values. /; Preprint SC 88-10
    Author: Chow, Shui-Nee
    Contributer: Deng, Bo , Fiedler, Bernold
    Publisher: Berlin :Konrad-Zuse-Zentrum für Informationstechnik,
    Year of publication: 1988
    Series Statement: Preprint / Konrad-Zuse-Zentrum für Informationstechnik Berlin Preprint SC 88-10
    ISSN: 0933-7911
    Type of Medium: Book
    Language: English
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2014-02-26
    Keywords: ddc:000
    Language: English
    Type: reportzib , doc-type:preprint
    Format: application/pdf
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    s.l. ; Stafa-Zurich, Switzerland
    Solid state phenomena Vol. 121-123 (Mar. 2007), p. 735-738 
    ISSN: 1662-9779
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Physics
    Notes: Iron oxide and its hydrate nanoparticles were synthesized by hydrothermal method andconfirmed by infrared and SEM (Scanning Electron Microscope) et al. The dimensions of thenanoparticles are about 50-120 nm. The crystalline form of iron oxide nanoparticles is likeglobosity while its hydrate rod. Amino acids intermingling with the synthesized nanoparticles werecrystallized to investigate the space effect of the nanoparticles. The crystalline forms of crystal aredifferent to that of pure amino acid. The positions and width of the nanoparticles’ peaks in theinfrared spectrum are changed too. Microscope observation and infrared spectrum results indicatedthe nanoparticles had changed the internal structure of amino acids crystal. To considerate thetoxicity of the synthesized nanoparticles, MTT (3-(4,5-dimethylthiazol 2-yl)-2,5diphenyltetrazolium bromide) assay was used to determine their cytotoxicity. The OD value(Optical Density) was used to calculated RGR% (Relative Generation Rate) of cells, whichdetermined the grade of cytotoxicity. The RGR of nanoparticles of iron oxide and its hydrate areabout 1 to 2, which indicate they have just low toxicity
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Woodbury, NY : American Institute of Physics (AIP)
    Chaos 11 (2001), S. 514-525 
    ISSN: 1089-7682
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Consideration is given to a basic food chain model satisfying the trophic time diversification hypothesis which translates the model into a singularly perturbed system of three time scales. It is demonstrated that in some realistic system parameter region, the model has a unimodal or logistic-like Poincaré return map when the singular parameter for the fastest variable is at the limiting value 0. It is also demonstrated that the unimodal map goes through a sequence of period-doubling bifurcations to chaos. The mechanism for the creation of the unimodal criticality is due to the existence of a junction-fold point [B. Deng, J. Math. Biol. 38, 21–78 (1999)]. The fact that junction-fold points are structurally stable and the limiting structures persist gives us a rigorous but dynamical explanation as to why basic food chain dynamics can be chaotic. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    FEMS microbiology reviews 13 (1994), S. 0 
    ISSN: 1574-6976
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Abstract: The possible roles of oxalic acid, veratryl alcohol, and manganese were investigated in relation to lignin biodegradation by white-rot basidiomycetes. Oxalate inhibited both lignin peroxidase (LiP) and manganese-peroxidase (MnP). and was decarboxylated by the mediation of veratryl alcohol and Mn. Oxalate was shown to regulate the mineralization of lignin in the in vivo system of Phanerochaete chrysosporium. In the brown-rot wood decay process, oxalic acid may serve as an acid catalyst as well as an electron donor for the Fenton reaction, to breakdown cellulose and hemicellulose. Oxaloacetase and glyoxylate oxidase may play a key role in production of oxalic acid by white-rot and brown-rot basidiomycetes such as Phanerochaete chrysosporium, Coriolus versicolor and Tyromyces palustris. A possible role of oxalate metabolism is discussed in relation to the physiology of wood-rotting fungi.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Journal of mathematical biology 38 (1999), S. 21-78 
    ISSN: 1432-1416
    Keywords: Key words: Bursting-spiking oscillations ; Continuous spiking oscillations ; Kneading sequence ; Period-doubling cascade ; Turning point ; Junction point ; Junction-fold point ; Slow manifold ; Stable and unstable foliations ; Poincaré map ; Asymptotic expansion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract  In the presence of stimulatory concentrations of glucose, the membrane potential of pancreatic β-cells may experience a transition from periods of rapid spike-like oscillations alternating with a pseudo-steady state to spike-only oscillations. Insulin secretion from β-cells closely correlates the periods of spike-like oscillations. The purpose of this paper is to study the mathematical structure which underlines this transitional stage in a pancreatic β-cell model. It is demonstrated that the transition can be chaotic but becomes more and more regular with increase in glucose. In particular, the system undergoes a reversed period-doubling cascade leading to the spike-only oscillations as the glucose concentration crosses a threshold. The transition interval in glucose concentration is estimated to be extremely small in terms of the rate of change for the calcium dynamics in the β-cells. The methods are based on the theory of unimodal maps and the geometric and asymptotic theories of singular perturbations.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Zeitschrift für angewandte Mathematik und Physik 46 (1995), S. 872-882 
    ISSN: 1420-9039
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Physics
    Notes: Abstract We consider Keller's functions, namely polynomial functionsf:C n →C n with detf(x)=1 at allx εC n. Keller conjectured that they are all bijective and have polynomial inverses. The problem is still open. Without loss of generality assumef(0)=0 andf'(0)=I. We study the existence of certain mappingsh λ, λ 〉 1, defined by power series in a ball with center at the origin, such thath′λ(0)=I andh λ(λf(x))=λh λ(x). So eachh λ conjugates λf to its linear part λI in a ball where it is injective. We conjecture that for Keller's functionsf of the homogeneous formf(x)=x +g(x),g(sx)=s dg(x),g′(x)n=0,xεC n,sεC the conjugationh λ for λf is anentire function.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Journal of dynamics and differential equations 2 (1990), S. 177-244 
    ISSN: 1572-9222
    Keywords: homoclinic orbit ; period doubling ; pathfollowing ; global bifurcation ; resonance ; 34C15 ; 34C35 ; 58F14
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract We consider a bifurcation of homoclinic orbits, which is an analogue of period doubling in the limit of infinite period. This bifurcation can occur in generic two parameter vector fields when a homoclinic orbit is attached to a stationary point with resonant eigenvalues. The resonance condition requires the eigenvalues with positive/negative real part closest to zero to be real, simple, and equidistant to zero. Under an additional global twist condition, an exponentially flat bifurcation of double homoclinic orbits from the primary homoclinic branch is established rigorously. Moreover, associated period doublings of periodic orbits with almost infinite period are detected. If the global twist condition is violated, a resonant side switching occurs. This corresponds to an exponentially flat bifurcation of periodic saddle-node orbits from the homoclinic branch.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Journal of dynamics and differential equations 5 (1993), S. 417-467 
    ISSN: 1572-9222
    Keywords: Strong inclination property ; neutrally twisted homoclinic orbits ; cusp horseshoe maps ; quotient symbolic systems ; singular perturbations ; 00A71 ; 34A34 ; 34C28 ; 34D30 ; 58F12 ; 58F13 ; 58F14 ; 58F40
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract Chaotic dynamics arises when the unstable manifold of a hyperbolic equilibrium point changes its twist type along a homoclinic orbit as some generic parameter is varied. Such bifurcation points occur naturally in singularly perturbed systems. Some quotient symbolic systems induced from the Bernoulli symbolic system on two symbols are proved to be characteristic for this new mechanism of chaos generation. Combination of geometrical and analytical methods is proved to be more fruitful.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1997 (1997), S. 2169-2175 
    ISSN: 0947-3440
    Keywords: Baker-Venkataraman rearrangement ; 3-Methoxyflavones ; Phase-transfer catalysis ; Catalytic transfer hydrogenation ; Transesterifications ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Some 3-methoxyflavones were known to possess antipicornavirus properties. In order to study the structure-activity relationship, attempts to prepare 3-methoxyflavone by literature methods were unsuccessful. We have modified the Baker-Venkataraman rearrangement, using a solid base and a phase-transfer catalyst. After searching optimal reaction conditions and a study of the intermediate formed in a model reaction, good yields were obtained for the 3-methoxyflavones 7, 21-32. Further some of the corresponding 7-O-n-butyl derivatives 4, 33-37 could be isolated as side products.
    Additional Material: 5 Tab.
    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...