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991.
Combining the constraints of Kähler differential geometry with the universality of the normal coordinate expansion in the background field method, we study the ultraviolet behavior of 2-dimensional supersymmetric non-linear -models with target space an arbitrary riemannian manifoldM. We show that the constraint ofN=2 supersymmetry requires that all counterterms to the metric beyond one-loop order be cohomologically trivial. It follows that such supersymmetric non-linear -models defined on locally symmetric spaces are super-renormalizable and thatN=4 models are on-shell ultraviolet finite to all orders of perturbation theory. 相似文献
992.
Kazimierz Frąckiewicz 《General Relativity and Gravitation》1985,17(10):953-970
It is shown that in the ECSK theory (coupled to an arbitrary tensor matter field) the degeneration distribution of the symplectic 2-form is closely connected with the action of the gauge groupG in the space of solutions to the field equations. 相似文献
993.
Marcel Erné 《Order》1985,2(2):199-210
A standard extension for a poset P is a system Q of lower ends (descending subsets) of P containing all principal ideals of P. An isomorphism between P and Q is called recycling if [Y]Q for all YQ. The existence of such an isomorphism has rather restrictive consequences for the system Q in question. For example, if Q contains all lower ends generated by chains then a recycling isomorphism between P and Q forces Q to be precisely the system of all principal ideals. For certain standard extensions Q, it turns out that every isomorphism between P and Q (if there is any) must be recycling. Our results include the well-known fact that a poset cannot be isomorphic to the system of all lower ends, as well as the fact that a poset is isomorphic to the system of all ideals (i.e., directed lower ends) only if every ideal is principal. 相似文献
994.
P. Kozma P. Bém B. P. Ad'yasevich V. G. Antonenko 《Czechoslovak Journal of Physics》1985,35(10):1118-1127
The parametrization of polarization observables in terms of (l, s, J) matrix elements is given for2H(d, p)3H and2H(d, n)3He reactions at low energies. It is shown that transverse polarizations of outgoing nucleons are to be measured in order to obtain a complete set of cross-section, analysing powers, spin-correlation and polarization transfer experiments. 相似文献
995.
996.
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999.
F. J. Coetzer T. C. Kotzé P. B. Kotzé F. J. Mostert P. van der Westhuizen 《Zeitschrift für Physik A Hadrons and Nuclei》1985,320(3):359-362
Detailed measurements on the 5p 4 S 3 2/0 and 5p~' 2 D 5 2/0 levels in Kr II are reported. Cascade effects were taken into account with the aid of the arbitrarily normalized decay curve (ANDC) technique. Experimental values are compared to values obtained by other investigators as well as to theoretical values. 相似文献
1000.
J. Lédé 《Journal of Thermal Analysis and Calorimetry》1996,46(1):67-84
This paper deals with models describing the thermal and chemical behaviour of solid particles undergoing fast endothermic reactions under the influence of an external heat flux. The heat source temperature is supposed to be constant, to increase with time, or to deliver a simple thermal flash. It is shown that the pyrolysis conditions (reaction temperature, conversion, etc.) depend on the chemical characteristics of the reaction and also to a large extent on the external heating conditions. Relationships are proposed to take into account these parameters. The results are applied to the thermal decomposition of NaHCO3. The pyrolysis of cellulose is finally chosen in order to show how these operating parameters can also affect the selectivity of a more complex reaction. 相似文献