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991.
B. Luk'yanchuk N. Bityurin N. Arnold D. Bäuerle 《Applied Physics A: Materials Science & Processing》1996,62(5):397-401
The role of non-stationary effects in nano-second ultraviolet (UV) excimer-laser ablation of organic polymers is discussed. The model includes reversible changes in absorption related to darkening and bleaching effects. Comparison of calculations and experimental data for polyimide demonstrates that the photophysical model describes the ablation kinetics quite well. 相似文献
992.
Chemical processing with lasers: Recent developments 总被引:1,自引:0,他引:1
D. Bäuerle 《Applied physics. B, Lasers and optics》1988,46(3):261-270
Chemical processing of materials with lasers is a new and interdisciplinary field with many already realized and potential applications in different areas of technology. This overview summarizes some recent developments in this rapidly expanding field. 相似文献
993.
K. Gäbel Ch. Bergmann E. Fill E. Förster I. Uschmann 《Applied physics. B, Lasers and optics》1993,56(1):3-7
Photo-resonant pumping of X-ray lasers requires close coincidence of a strong emission line with a suitable absorbing transition. We use a high-resolution crystal spectrometer to verify five coincidences, one of which has apparently not yet appeared in published work. All but one of the coincidences are found to lie within one linewidth. With respect to X-ray laser photo-pumping three of the five coincidences seem to be promising candidates. 相似文献
994.
Aminoacidesters and hydroxymethylphosphines form the title compounds, which react as bidentate ligands with Mo (CO)6 to give the cyclic Mo (CO)4 -complexes. 相似文献
995.
Assuming that the conduction electrons of an amorphous metal contribute to the binding, we investigate whether a magnetic field will influence the transition from the amorphous to the crystalline state. Measurements taken on amorphous Bi, Ga and Yb films show no change in the crystallization temperatures within an accuracy of ±0.1 K due to a magnetic field of 18.5 T parallel to the surface of the films.Dedicated to Prof. Dr. W. Buckel on the occasion of his 60th birthday 相似文献
996.
A. B. Sharma S. J. Halme M. Lähteenoja E. J. R. Hubach 《Optical and Quantum Electronics》1983,15(2):95-111
Based on the near-field filtration formulation, the paper identifies and quantifies the most important sources of interlaboratory error in multimode fibre attenuation measurements. Measures are proposed for the reduction of these errors, and it is estimated that a lower bound of about 0.04 dB should be possible under certain assumptions. 相似文献
997.
A high frequency transmission line periodically loaded with varactor diodes is presented to study nonlinear wave propagation.
The nonlinearity and dispersion characteristics are experimentally and theoretically analysed. Experimental results on shock
wave formation and harmonic frequency generation are found to be in good agreement with theoretical predictions. The influence
of dispersion on second-harmonic frequency generation is particularly discussed yielding large values of the efficiency. 相似文献
998.
999.
J. Bräuninger 《Numerische Mathematik》1981,36(4):359-373
Summary This paper presents a modification of the BFGS-method for unconstrained minimization that avoids computation of derivatives. The gradients are approximated by the aid of differences of function values. These approximations are calculated in such a way that a complete convergence proof can be given. The presented algorithm is implementable, no exact line search is required. It is shown that, if the objective function is convex and some usually required conditions hold, the algorithm converges to a solution. If the Hessian matrix of the objective function is positive definite and satisfies a Lipschitz-condition in a neighbourhood of the solution, then the rate of convergence is superlinear. 相似文献
1000.
Heiner-Müller-Merbach T. Gal J. Niedereichholz Ch. Schneeweiβ B. Schiemenz W. Törnig D. Hochstädter H. Schellhaas K. Weber G. Reckel W. Dinkelbach W. Rödder 《Mathematical Methods of Operations Research》1973,17(3):158-165
Ohne Zusammenfassung 相似文献