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941.
Orsolya Hakkel Zoltán Pászti Tamás Keszthelyi Krisztina Frey László Guczi 《Reaction Kinetics and Catalysis Letters》2009,96(2):345-356
In this work a complex experimental setup is described which was developed by connecting an ultra-high vacuum multi-technique
surface analysis system and a sum frequency generation vibrational spectrometer. This arrangement provides a unique environment
to study interfaces under in situ conditions by a combination of complementary techniques. Preliminary results of CO adsorption experiments on gold and iron
oxide thin layers grown on gold are presented as application examples of the experimental setup. 相似文献
942.
943.
944.
Wenjie Xie Siu-Chung Tam Yee-Loy Lam Hongru Yang Jianhui Gu Gang Zhao Wilson Tan 《Optics & Laser Technology》1999,31(8):555-558
Based on space-dependent rate equation, the lowest threshold input power for diode end-pumped solid state lasers is obtained for pump spot size wp → 0. However, when the pump beam waist is decreased, the far-field half-angle increases due to the same beam quality, which will influence the match between the pump volume and mode volume. Most importantly, when the pump beam waist is decreased, the temperature and temperature gradient in the laser rod would be very high due to the resulting heat, which would cause material distortion, variation of refractive index, instability of laser resonator etc. We analyze the temperature distributions with different pump beam sizes and conclude that the condition wp ≈ w0 (the radius of the laser beam at the laser rod) is often taken as a rough guide to the optimum case. 相似文献
945.
946.
In this paper, we first present the Grammian determinant solutions to the non-isospectral and variable-coefficient Kadomtsev-Petviashvili (vcKP) equation. Then, by using the pfaffianization procedure of Hirota and Ohta, a new non-isospectral and variable-coefficient integrable coupled system is generated. Moreover, Gramm-type pfaffian solutions of the pfaffianized system are proposed. 相似文献
947.
Tamás Szőnyi 《Designs, Codes and Cryptography》1996,8(3):327-332
Let H be a subgroup of a cyclic Singer group of PG (n,q). In this paper we study the following problem: When is a point orbit of H a cap? A necessary and sufficient condition for this is derived and used to give a short proof of some results by Ebert [6] and to show that small orbits are typically caps. 相似文献
948.
Symmetry classes of tensors associated with certain groups 总被引:1,自引:0,他引:1
We discuss the existence of an orthogonal basis consisting of decomposable vectors for some symmetry classes of tensors associated with certain subgroups of the full symmetric group The dimensions of these symmetry classes of tensors are also given 相似文献
949.
950.
Tamás Rapcsák 《Journal of Global Optimization》2008,40(1-3):375-388
The aim of the paper is to show how to explicitly express the function of sectional curvature with the first and second derivatives
of the problem’s functions in the case of submanifolds determined by equality constraints in the n-dimensional Euclidean space endowed with the induced Riemannian metric, which is followed by the formulation of the minimization
problem of sectional curvature at an arbitrary point of the given submanifold as a global minimization one on a Stiefel manifold.
Based on the results, the sectional curvatures of Stiefel manifolds are analysed and the maximal and minimal sectional curvatures
on an ellipsoid are determined.
This research was supported in part by the Hungarian Scientific Research Fund, Grant No. OTKA-T043276 and OTKA-K60480. 相似文献