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131.
Summary The maturation of wheat varieties with different harvest times has been examined by high-performance capillary electrophoresis.
The unique proteins of the albumin, gliadin and glutenin fractions of Hungarian winter wheat cultivars Bánkúti 1201 (early
harvest time), Martonvásári 23 (medium harvest time), and Martonvásári 15 (semi-late harvest time) were analysed. An acidic
phosphate buffer containing a polymeric additive and organic modifiers was used in capillary zone electrophoresis mode. Formation
of albumin followed the same time scale, and the patterns were quite similar, for all three cultivars. For gliadins and glutenins
the time scale and patterns were different and some correlation was observed between harvest time and gliadin formation.
Presented at Balaton Symposium '01 on High-Performance Separation Methods, Siófok, Hungary, September 2–4, 2001 相似文献
132.
G. Debnath Frank Moss F. Marchesoni Th. Leiber H. Risken 《Journal of statistical physics》1989,54(5-6):1381-1382
A qualitative change in the topology of the joint probability densityP(,x), which occurs for strongly colored noise in multistable systems, has recently been observed first by analog simulation (F. Moss and F. Marchesoni,Phys. Lett. A
131:322 (1988)) and confirmed by matrix continued fraction methods (Th. Leiber and H. Riskin, unpublished), and by analytic theory (P. Hänggi, P. Jung, and F. Marchesoni,J. Stat. Phys., this issue). Systems studied were of the classx=–U(x)/x+(t,), whereU(x) is a multistable potential and (t, ) is a colored, Gaussian noise of intensityD, for which =0, and (t) (s)=(D/)exp(–t–s/). When the noise correlation time is smaller than some critical value 0, which depends onD, the two-dimensional densityP(,x) has the usual topology [P. Jung and H. Risken,Z. Phys. B
61:367 (1985); F. Moss and P. V. E. McClintock,Z. Phys. B
61:381 (1985)]: a pair of local maxima ofP(,x), which correspond to a pair of adjacent local minima ofU(x), are connected by a single saddle point which lies on thex axis. When >0, however,the single saddle disappears and is replaced by a pair of off-axis saddles. A depression, or hole, which is bounded by the saddles and the local maxima thus appears. The most probable trajectory connecting the two potential wells therefore does not pass through the origin for >0, but instead must detour around the local barrier. This observation implies that successful mean-first-passage-time theories of strongly colored noise driven systems must necessarily be two dimensional (Hänggiet al.). We have observed these holes for several potentialsU(x): (1)a soft, bistable potential by analog simulation (Moss and Marchesoni); (2) a periodic potential [Th. Leiber, F. Marchesoni, and H. Risken,Phys. Rev. Lett.
59:1381 (1987)] by matrix continued fractions; (3) the usual hard, bistable potential,U(x)=–ax
2/2+bx
4/4, by analog simulations only; and (4) a random potential for which the forcingf(x)=–U(x)/x is an approximate Gaussian with nonzero correlation length, i.e., colored spatiotemporal noise, by analog simulation. There is a critical curve 0(D) in the versusD plane which divides the two topological behaviors. For a fixed value ofD, this curve is shifted toward larger values of 0 for progressively weaker barriers between the wells. Therefore, strong barriers favor the observation of this topological transformation at smaller values of . Recently, an analytic expression for the critical curve, valid asymptotically in the small-D limit, has been obtained (Hänggiet al.).This paper will appear in a forthcoming issue of theJournal of Statistical Physics. 相似文献
133.
The representation of diatomic potential energy curves by rational fractions using low order polynomials in numerator and denominator is investigated. The rational fraction method, which is illustrated by examples, is shown to fail in providing a robust representation of diatomic potentials for wide application. 相似文献
134.
Yan-zhongZhang Zhi-qiangFan Bai-gengWu Jun-tingXu QiWang 《高分子科学》2004,(3):231-238
Spherical polyethylene/polypropylene (PE/PP) in-reactor blend granules with various ethylene/propylene molar ratios and high porosity were synthesized using a high yield TiCl4/MgCl2 supported catalyst. A solution of benzoyl peroxide (BPO)/maleic anhydride (MAH)/xylene (interfacial reagent) or BPO/MAH/St (comonomer) was absorbed onto the PE/PP inreactor blend granules, and solid phase gratt polymerization of MAH on PE/PP was conducted. The amount of grafted MAH on PE/PP was measured through chemical titration. The results showed that solid phase graft polymerization of MAH in PE/PP in-reactor blend granules produced graft copolymer with high amount of grafted MAH, and the amount of grafted MAH was raised slightly when St was introduced as comonomer. The graft in-reactor blend was fractionated into five fractions through temperature-gradient extraction fractionation (TGEF), and the fractions were analyzed by FTIR. The results revealed that MAH is mainly grafted on the PE segments, whereas MAH was predominantly grafted on the PP segments when St was present in the graft polymerization system. In addition, the final product is still in the form of regular spherical granules, which is beneficial for industrial processing. 相似文献
135.
《Indagationes Mathematicae》2022,33(6):1189-1220
This paper investigates the quadratic irrationals that arise as periodic points of the Gauss type shift associated to the odd continued fraction expansion. It is shown that these numbers, which we call O-reduced, when ordered by the length of the associated closed primitive geodesic on some modular surface , are equidistributed with respect to the Lebesgue absolutely continuous invariant probability measure of the Odd Gauss shift. 相似文献
136.
Xiao-Yan Zhang Ji-Suo Wang Xiang-Guo Meng Jie Su 《International Journal of Theoretical Physics》2009,48(3):803-814
Using the coherent state representation of Wigner operator and the technique of integration within an ordered product (IWOP)
of operators, the Wigner functions of the even and odd negative binomial states (NBSs) are obtained. We concentrate our analysis
on the fact that the even and odd NBSs interpolate between the even and odd coherent states and the even and odd quasi-thermal
states depending on the values of the parameters involved. Moreover, the tomograms of the even and odd NBSs are calculated
by virtue of intermediate coordinate-momentum representation in quantum optics.
Project 10574060 supported by the National Natural Science Foundation of China and project Q2007A01 supported by the Natural
Science Foundation of Shandong Province. 相似文献
137.
138.
In this article we carry on the study of the fundamental category (Goubault and Raussen, Dihomotopy as a tool in state space
analysis. In: Rajsbaum, S. (ed.) LATIN 2002: Theoretical Informatics. Lecture Notes in Computer Science, vol. 2286, Cancun,
Mexico, pp. 16–37, Springer, Berlin Heidelberg New York, 2002; Goubault, Homology, Homotopy Appl., 5(2): 95–136, 2003) of a partially ordered topological space (Nachbin, Topology and Order, Van Nostrand, Princeton, 1965; Johnstone, Stone Spaces, Cambridge University Press, Cambridge, MA, 1982), as arising in e.g. concurrency theory (Fajstrup et al., Theor. Comp. Sci. 357: 241–278, 2006), initiated in (Fajstrup et al., APCS, 12(1): 81–108, 2004). The “algebra” of dipaths modulo dihomotopy (the fundamental category) of such a po-space is essentially finite in a number
of situations. We give new definitions of the component category that are more tractable than the one of Fajstrup et al. (APCS,
12(1): 81–108, 2004), as well as give definitions of future and past component categories, related to the past and future models of Grandis (Theory
Appl. Categ., 15(4): 95–146, 2005). The component category is defined as a category of fractions, but it can be shown to be equivalent to a quotient category,
much easier to portray. A van Kampen theorem is known to be available on fundamental categories (Grandis, Cahiers Topologie
Géom. Différentielle Catég., 44: 281–316, 2003; Goubault, Homology, Homotopy Appl., 5(2): 95–136, 2003), we show in this paper a similar theorem for component categories (conjectured in Fajstrup et al. (APCS, 12(1): 81–108,
2004). This proves useful for inductively computing the component category in some circumstances, for instance, in the case of
simple PV mutual exclusion models (Goubault and Haucourt, A practical application of geometric semantics to static analysis
of concurrent programs. In: Abadi, M., de Alfaro, L. (eds.) CONCUR 2005 – Concurrency Theory: 16th International Conference,
San Francisco, USA, August 23–26. Lecture Notes in Computer Science, vol. 3653, pp. 503–517, Springer, Berlin Heidelberg New
York, 2005), corresponding to partially ordered subspaces of R
n
minus isothetic hyperrectangles. In this last case again, we conjecture (and give some hints) that component categories enjoy
some nice adjunction relations directly with the fundamental category.
相似文献
139.
S. M. Zen’kovskaya V. A. Novosyadlyi 《Computational Mathematics and Mathematical Physics》2008,48(9):1669-1679
The effect of single- and two-frequency vibrations on the behavior of a system consisting of two homogeneous viscous fluids bounded by rigid walls is analyzed. It is assumed that the system as a whole is under vertical vibrations obeying a certain law. An eigenvalue problem is obtained in order to analyze the stability of the relative equilibrium. The case of finite frequencies and arbitrary modulation amplitudes is treated along with the case of high frequencies and small modulation amplitudes. In the former case, the parametric resonance domains are examined depending on the parameters of the system. In the latter case, the high-frequency vibration is shown to create effective surface tension, thus flattening the interface, and can suppress instability when the heavy fluid is over the light one. 相似文献
140.
It is shown that each rational approximant to (ω,ω2)τ given by the Jacobi–Perron algorithm (JPA) or modified Jacobi–Perron algorithm (MJPA) is optimal, where ω is an algebraic function (a formal Laurent series over a finite field) satisfying ω3+kω-1=0 or ω3+kdω-d=0. A result similar to the main result of Ito et al. [On simultaneous approximation to (α,α2) with α3+kα-1=0, J. Number Theory 99 (2003) 255–283] is obtained. 相似文献