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991.
992.
F. Präßler Volker Hoffmann Joachim Schumann Klaus Wetzig 《Fresenius' Journal of Analytical Chemistry》1996,355(7-8):840-846
An algorithm is presented as a concept for the quantification in direct current and radiofrequency glow discharge (GD) modes for GD optical emission spectroscopy. The algorithm is divided into excitation and sputtering part and thus it is possible to distinguish between the different excitation processes and to consider equivalent sputtering crater formations in both modes. Intensity-time profiles are affected corresponding to the method by several effects. One important effect is that sputtering occurs at a single time in different depths because of curved crater bottoms, this is usually called crater effect. The main purpose is to introduce an iterative deconvolution technique which for the quantification numerically takes into account the curved sputtering crater bottom. Input data for the deconvolution technique are the calibrated mass-time profile, the partial densities of the sample constituents and the measured final shape of the sputtering crater. Using a relatively simple model for ion sputtering the deconvolution technique improves iteratively the calculated layer structure by means of information on crater formation. The mathematical handling is illustrated for the quantification of a depth profile of a multilayer sample of ten 100 nm layers. The resulting concentration-depth profile reflects excellently the real elemental distribution of the multilayer system. 相似文献
993.
Consider a ring on which customers arrive according to a Poisson process. Arriving customers drop somewhere on the circle and wait there for a server who travels on the ring. Whenever this server encounters a customer, he stops and serves the customer according to an arbitrary service time distribution. After the service is completed, the server removes the client from the circle and resumes his journey.We are interested in the number and the locations of customers that are waiting for service. These locations are modeled as random counting measures on the circle. Two different types of servers are considered: The polling server and the Brownian (or drunken) server. It is shown that under both server motions the system is stable if the traffic intensity is less than 1. Furthermore, several earlier results on the configuration of waiting customers are extended, by combining results from random measure theory, stochastic integration and renewal theory. 相似文献
994.
995.
996.
A three-dimensional potential energy surface for the photodissociation of H2O in its lowest excited singlet state 1B1 in C2v or 1A″ in C3 symmetry, respectively, has been calculated with quantum-chemical ab initio methods including electron correlation. The main features of the surface are discussed and qualitative explanations are given for the experimentally observed vibrational and rotational excitations of the product OH(2Π) radicals. The surface will be used in subsequent investigations of the dynamics of the H2O photodissociation process. 相似文献
997.
998.
Dipl. Math. Hans-Wiegand Binzer Prof. Dr. Volker Mammitzsch 《manuscripta mathematica》1979,30(4):383-386
A theorem of W.RUPP [4] on integration of correspondences (set-valued functions) is slightly generalized and a new short proof is given by means of a measurability concept for correspondences which was introduced by H.RICHTER [3]. 相似文献
999.
Complexes have been obtained by the reaction of iron atoms with butadiene or styrene at - 196°C followed by treatment with ligands such as CO or (MeO)3P. 相似文献
1000.