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91.
Characterizations of some properties of generalized R 0 and R 1 topological spaces by using closure operator defined on a generalized topological space will be given. It is also shown that many results done in this area in some previous papers can be considered as special cases of our results.  相似文献   
92.
The radiative decayJ/ψ → γ π+ π? has been studied using the 8.6 millionJ/ψ produced in the DM2 experiment at the DCIe +e? storage rings at Orsay. The π+ π? mass spectrum shows a cleanf 2 (1270) signal, and the possible presence of two other states at thef 2 (1720) andf 4 (2030) masses. For thef 2 (1270), the branching ratio BR(J/ψ →γf)xBR(f→π+ π?) is measured to be (7.50±0.30±1.12)×10?4, and the spin analysis prefers theJ=2 assignment, with helicity parametersx=0.83±0.06 andy=0.01±0.06. The existence of higher mass states is discussed.  相似文献   
93.
We consider the Lie-Backlund symmetries and conservation laws of a perturbed KdV equation and NLS equation. The arbitrary coefficients of the perturbing terms can be related to the condition of existence of nontrivial LB symmetry generator. When the perturbed KdV equation is subjected to Painlevé analysisa la Weiss, it is found that the resonance position changes compared to the unperturbed one. We prove the compatibility of the overdetermined set of equations obtained at the different stages of recursion relations, at least for one branch. All other branches are also indicated and difficulties associated them are discussed considering the perturbation parameter to be small. We determine the Lax pair for the aforesaid branch through the use of Schwarzian derivative. For the perturbed NLS equation we determine the conservation laws following the approach of Chen and Liu. From the recurrence of these conservation laws a Lax pair is constructed. But the Painlevé analysis does not produce a positive answer for the perturbed NLS equation. So here we have two contrasting examples of perturbed nonlinear equations: one passes the Painlevé test and its Lax pair can be found from the analysis itself, but the other equation does not meet the criterion of the Painlevé test, though its Lax pair is found in another way.  相似文献   
94.
Zusammenfassung Der Verfasser behandelt die Wirbelstr?mung um Pfeilflügel. Diese Str?mung ist, bei etwas h?heren Anstellwinkeln, gekennzeichnet durch die Ausbildung einer Singularit?t, die er ?Wickelfl?che? (nappe en cornet) nennt. Die Konfiguration am Rand dieser Wirbelfl?che wird analysiert. Weiter wird das Bild einer konischen Str?mung für einen unendlichen Delta-Flügel untersucht; dabei wird genauer auf den Sinn der Singularit?ten eingegangen, die zu den Wirbeln der ?Wickelfl?che? oder den von der Pseudo-Str?mung in einer Querebene gebildeten Wülsten dieser Fl?che hinzugefügt werden, und die den Charakter von Quellen oder Senken haben. Der Verfasser diskutiert die Bedeutung der Staupunkte, der Trenn- und Abl?sungs-Linien und legt dar, wie man die Ausbildung der Wülste und weiter der ?Wickelfl?che? selbst als das Ergebnis des Zusammenfliessens der beiden Grenzschichten von Ober- und Unterseite auffassen kann, wobei diese letztere zur Oberseite hinüberstr?mt. Schliesslich wird die Bildung von Gegenwirbeln untersucht. O. N. E. R. A. (Office national d'études et de recherches aéronautiques).  相似文献   
95.
If μ and λ are probability measures on a metrisable compact convex set with μ < λ in the Choquet sense, then the main object of this paper is the study of the extremal structure of the convex set of all dilations carrying μ to λ. The extremal dilations are characterized and the relationships between these dilations and the extremal measures they induce are investigated. Several examples of extremal dilations with special properties are given to illustrate their behavior. Also given is a systematic characterization of measures which are extreme in the convex set of all measures dominating μ in the Choquet ordering.  相似文献   
96.
Thin films (25-2500 Å) of C60 molecules have been deposited on both (001) NaCl and mica substrates at varying temperatures by resistive evaporation. Both electron diffraction and high resolution microscopy have been used to assess the degree of crystallinity, the orientational ordering and the nature of the defects present in these face-centered-cubic films. For NaCl, optimum conditions yielded polycrystalline films with a tendency towards a 110 orientation, while for mica, extended single crystal films have been fabricated which exhibit a 111 direction normal to the film surface.  相似文献   
97.
98.
The analysis in this paper looks at two important elements in modelling the market for timber in the United States. First, the issue of directional causality between price and quantity and its implications in a modelling effort is investigated. Second, the extent of the geographic market for timber is discussed and a method of detecting it is suggested. The method for detecting the extent of the geographical market is tractable and can be applied in a straightforward way. Both considerations are applied to the softwood lumber market in the United States.  相似文献   
99.
Hydromagnetic turbulent shear flow of viscous, incompressible, electrically conducting fluid between two infinite uniformly porous moving parallel planes in the presence of axial and transverse magnetic field has been studied by the semi-empirical method. The expressions for the mean distributions for velocity and magnetic field for turbulent shear flow have been obtained for both the cases. As particular cases, the results have been obtained if the planes are fixed. The solutions obtained when the magnetic field is axial have been shown graphically for turbulent and laminar flows.  相似文献   
100.
This is summary of the activities of the working group on collider physics in the IXth Workshop on High Energy Physics Phenomenology (WHEPP-9) held at the Institute of Physics, Bhubaneswar, India in January 2006. Some of the work subsequently done on these problems by the subgroups formed during the workshop is included in this report.  相似文献   
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