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951.
A novel combination of backlighting and glare point velocimetry and sizing (GPVS) is proposed to measure the size distribution
of microbubbles (or microdroplets). This new technique, which we will call laser marked shadowgraphy, avoids sizing out-of-focus
bubbles (or droplets) and the associated bias error. Compared to backlighting, this combination also improves the precision
of the diameter measurement and allows void fraction measurements. Compared with GPVS, a more robust image processing is obtained.
The applicability of the developed technique is demonstrated on a cloud of electrochemically generated hydrogen bubbles. 相似文献
952.
57Co was implanted in different reactive and non reactive frozen gases like Ne, Ar, N2, Xe, CH4 and C2H4. Higher ionization states of Fe and cryochemical compounds are detected. 相似文献
953.
George Eng Pamela K. McKinney-Forbes Kristy L. Richie Van V. Nguyen
Leopold May
《Journal of organometallic chemistry》1986,310(3):285-291To obtain more structural information on complexes formed between alkyltin halides and bidentate ligands, the solid-state IR and Mössbauer spectra of the 1,2-ethanediamine and 1,4-butanediamine complexes of trimethyltin halides and dimethyltin dihalides were examined. The structures of the trimethyltin halide complexes were found to be trigonal bipyramidal with coplnar methyl groups. The dimethyltin dihalide complexes were octahedral with the methyl groups in the cis-positions and the halides trans to each other. However, there were no differences in the structures of the chloro and bromo complexes of either type. 相似文献
954.
955.
Multiple Wilson and Jacobi–Piñeiro polynomials 总被引:1,自引:1,他引:0
We introduce multiple Wilson polynomials, which give a new example of multiple orthogonal polynomials (Hermite–Padé polynomials) of type II. These polynomials can be written as a Jacobi–Piñeiro transform, which is a generalization of the Jacobi transform for Wilson polynomials, found by Koornwinder. Here we need to introduce Jacobi and Jacobi–Piñeiro polynomials with complex parameters. Some explicit formulas are provided for both Jacobi–Piñeiro and multiple Wilson polynomials, one of them in terms of Kampé de Fériet series. Finally, we look at some limiting relations and construct a part of a multiple AT-Askey table. 相似文献
956.
957.
F. A. Theopold E. Gerdau R. Hollatz H. Riege R. Rüffer R. Van Staa 《Hyperfine Interactions》1986,29(1-4):1555-1558
Construction and use of a function generator are presented. The flexible outline allows a high precision control for all required
velocity profiles. 相似文献
958.
959.
960.
Yves Van Ingelgem Els Tourwé Orlin Blajiev Rik Pintelon Annick Hubin 《Electroanalysis》2009,21(6):730-739
Electrochemical impedance spectroscopy (EIS) is a powerful technique to study electrochemical processes and to perform screening tasks. Recently an integrated measuring and modeling methodology for EIS based on a multisine excitation signal was developed. A key issue in this methodology is the data analysis, allowing us to rapidly quantify the reliability of the measured data. In this paper, a comparison is made between classical single‐sine and the proposed multisine measurements on the same system. The fitting of the impedance data obtained by single‐or multisine excitation and using different weighting factors is also discussed. In addition to the advantages reported in earlier work, it is concluded that, of all investigated frequencies, the odd random phase multisine excitation yields the highest quality data in the shortest measurement time. 相似文献