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71.
Mutual mass diffusion and thermal diffusion has been investigated in poly(dimethylsiloxane)/ poly(ethylmethylsiloxane) (PDMS/PEMS) polymer blends of equal weight fractions. Molar masses ranged from below 1 to over 20 kg/mol. Both the mutual mass (D) and the thermal diffusion (DT) coefficient contain a thermally activated factor with an activation temperature of 1415 K. The molar mass dependence of DT is due to an end-group effect of the local friction coefficient. The thermal diffusion coefficient in the limit of long chains and infinite temperature is DT0, = - 1.69×10-7cm2(sK)-1. The Soret coefficient ST of blends far enough away from a critical point is proportional to the static structure factor S(q = 0). 相似文献
72.
A new concept and its methodology for studying human meridians are presented based on rigorous and scientific observation
on the objective existence of human meridians in view of biomedical optics. According to this methodology, the infrared radiant
characteristics of acupuncture meridians over human body and the optical transport properties of light propagating along the
meridian are reported. This study, thus, confirms the existence of acupuncture meridians, sheds new light on an approach to
investigation of human meridians and offers a new perspective in understanding the potential meridian functions such as energy
and information transfer and physiological regulation.
Supported by the National Key Basic Research Program of China (Grant No. 2006CB504505), the National Natural Science Foundation
of China (Grant Nos. 60578056 and 30572309), the Science Research Foundation of Ministry of Health & United Fujian Provincial
Health and Education Project for Tackling the Key Research of China (Grant No. WKJ2005-2-004), the Young Scientists and Technicians
Innovation Project of Fujian Province (Grant No. 2007F3026), and the Fund from Fujian Normal University (Grant No. 2008100218) 相似文献
73.
Mónica ClappSergio Hernández-Linares Eric Hernández-Mart?&#x;nez 《Journal of Differential Equations》2002,185(1):181-199
We consider paths of functionals starting with one which is invariant under the action of an arbitrary group of symmetries. We give conditions for the existence of an unbounded sequence of critical values of the non-symmetric functional at the end of the path in terms of the growth of the critical values of the symmetric one. We apply this to obtain a multiplicity result for a system of elliptic equations whose symmetries are perturbed by a linear term and a non-homogeneous boundary condition. 相似文献
74.
Alexander Blokh Michal Misiurewicz 《Transactions of the American Mathematical Society》1999,351(1):63-78
We compare periodic orbits of circle rotations with their counterparts for interval maps. We prove that they are conjugate via a map of modality larger by at most 2 than the modality of the interval map. The proof is based on observation of trips of inhabitants of the Green Islands in the Black Sea.
75.
We improve over a sufficient condition given in [8] for uniqueness of a nondegenerate critical point in best rational approximation
of prescribed degree over the conjugate-symmetric Hardy space of the complement of the disk. The improved condition connects to error estimates in AAK approximation, and is necessary
and sufficient when the function to be approximated is of Markov type. For Markov functions whose defining measure satisfies
the Szego condition, we combine what precedes with sharp asymptotics in multipoint Padé approximation from [43], [40] in order
to prove uniqueness of a critical point when the degree of the approximant goes large. This lends perspective to the uniqueness
issue for more general classes of functions defined through Cauchy integrals. 相似文献
76.
Zheng-da Huang 《计算数学(英文版)》2000,(5)
1. IntroductionLetf(x) = 0 (1.1)where j: X - Y is a norilineax operator which maps Banach space X into Baaedspace Y. The well-known iteration methods for solving (1.1) are the Nixon methodaam very ldnds of its improvement methods. One of them is the so called King-Wernerm6thod denned bykw(p, x03 yo):which is established by King in [7], Werner in [12] in d~nt formulas, respectively.It is interesting that the method (1.2) is of order 1 fi with the same functioncompotatinn coSt and twO ti… 相似文献
77.
In this paper we introduce a weak contractive condition, called weakly φ-pair, for two mappings in the framework of cone metric spaces and we prove a theorem which ensures existence and uniqueness of
common fixed points for such mappings. Also we obtain a result on points of coincidence. These results extend and generalize
well-known comparable results in the literature.
The authors are supported by Università degli Studi di Palermo, R. S. ex 60%. 相似文献
78.
Harold R. Parks 《Journal of Mathematical Analysis and Applications》2006,324(2):934-940
A variant of lexicographic order called symmetrized-lexicographic order is defined. The symmetrized-lexicographic order finds its application in the goal programming procedure called the method of points. The symmetrized-lexicographic order is shown to be representable using linear algebra and, thus, the method of points can be implemented as a linear programming problem. 相似文献
79.
V. A. Yudin 《Mathematical Notes》1998,63(2):279-282
80.
Tomokuni Takahashi 《Mathematische Nachrichten》2013,286(4):402-429
We classify the algebraic surfaces with Eisenbud‐Harris general fibration of genus 4 over a rational curve or an elliptic curve whose slope attains the lower bound. The classification of our surfaces is strongly related to the result of the classification for certain relative quadric hypersurfaces in 3‐dimensional projective space bundles over a rational curve and an elliptic curve. We further prove some results about the canonical maps, the quadric hulls of the canonical images and the deformation for these surfaces. 相似文献