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991.
Tero Kilpeläinen 《Arkiv f?r Matematik》1999,37(2):275-289
We construct singular solutions to equations
similar to thep-Laplacian, that tend to ∞ on a given closed set ofp-capacity zero. Moreover, we show that everyG
δ-set of vanishingp-capacity is the infinity set of someA-superharmonic function.
The research is financed by the Academy of Finland (Project #8597). 相似文献
992.
During the last 50 years extensive experimental investigation has been carried out on the chemical effects of ultrasound, but limited work has been reported on modeling. This paper presents a new model in which a numerical calculation of the three-dimensional linear sound pressure field distribution in a commonly used sonoreactor containing three transducers is carried out. In this model the inhomogeneous three-dimensional time-dependent wave equation was solved using the finite difference approach. The modeled results are then compared with the experimentally measured values, and the agreement, in general, is found to be good. Further, our modeling studies have an advantage, since they clearly describe the continuous sound pressure field structure, unlike previously reported results in which some information is missing due to limited intermittent measured points. 相似文献
993.
Schmidt Jörg Guesdon Christine Schomäcker Reinhard 《Journal of nanoparticle research》1999,1(2):267-276
Engineering aspects of the preparation of palladium nanoparticles in non-ionic w/o-microemulsions are examined. In order to achieve reproducible synthesis conditions a semi-batch reactor with a standardized design is used. Influences of the stirring rate and of different ways of concentration control on the product properties are observed. For reproducible synthesis it is important to establish appropriate and defined preparation conditions. Monodisperse palladium particles of around 5nm size are obtained by adding the microemulsion containing the palladium salt at a constant feed rate to the precharged microemulsion containing the reducing agent. A quantitative kinetic model is proposed to describe particle formation in microemulsions. Unknown parameters of the model have been estimated by independent examinations or can be achieved by fitting to the experimental data. 相似文献
994.
W. Potzel C. Schäfer M. Steiner H. Karzel W. Schiessl M. Peter G. M. Kalvius T. Katila E. Ikonen P. Helistö J. Hietaniemi K. Riski 《Hyperfine Interactions》1992,72(1-3):195-214
A gravitational tedshift (GRS) experiment using the high-resolution Mössbauer resonance in67Zn is described. The tiny Doppler motion of the source can be checked by a dc-SQUID based displacement sensor. The results on the GRS strongly indicate that solid-state effects, which are difficult to control experimentally, finally limit the accuracy that Mössbauer measurements can provide in determining the GRS. We argue that for this reason conventional Mössbauer experiments most probably will not be able to compete with other methods in future GRS measurements of very high precision. 相似文献
995.
F. Dinkelacker M. Schäfer W. Ketterle J. Wolfrum W. Stolz J. Köhler 《Experiments in fluids》1992,13(5):357-359
A new method for the determination of the velocity field with all three velocity components in a light sheet was demonstrated that combines conventional particle tracking anemometry (PTA) with an intensity analysis of the particle flecks. The correlation between intensity and the dimension perpendicular to the light sheet was obtained from the monotonous variation of the laser light intensity across the width of the light sheet. 相似文献
996.
997.
Phenomenological models based on the master equation are analyzed to calculate the temperature and angular dependence of time of flight spectra in chemisorption. Strong deviations from Knudsen's cosine law and Maxwell's velocity distribution are produced. The Gaussian model seems of little relevance for the analysis of experimental data for which, in most cases, models incorporating activation barriers are needed. 相似文献
998.
Applied Biochemistry and Biotechnology - 相似文献
999.
1000.
Olle Häggström 《Journal of statistical physics》1996,84(5-6):1351-1361
We study the random-cluster model on a homogeneous tree, and show that the following three conditions are equivalent for a random-cluster measure: quasilocality, almost sure quasilocality, and the almost sure nonexistence of infinite clusters. As a consequence of this, we find that the plus measure for the Ising model on a tree at sufficiently low temperatures can be mapped, via a local stochastic transformation, into a measure which fails to be almost surely quasilocal. 相似文献