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1.
Hans-Jürgen Odenthal Herbert Pfeifer Ina Lemanowicz Rainer Gorissen 《Metallurgical and Materials Transactions B》2002,33(2):163-172
The present work describes quantitative digital particle image velocimetry measurements of a full-scale water model of a thin
slab mold. Different casting speeds and two submerged entry nozzles with one and two outlet ports have been investigated.
The flow pattern of the single-port nozzle shows a counterclockwise-rotating double vortex that is nearly steady-state but
leads to high stationary surface waves. The flow jets out of the two-port nozzle oscillate and produce a transient flow pattern
with low wave amplitudes. The amplitudes for the one-port nozzle show a linear variation with the volumetric flow rate. The
experimental results lead to a good interpretation of the flow phenomena and are used to validate steady-state numerical simulations
with the commercial program, CFX, on the basis of the Reynolds equations. To describe anisotropic turbulence effects, the
Reynolds stress model (RSM) is used for the flat single-port nozzle and the standard k-ɛ model for the mold flow. The calculated mean velocities and wave amplitudes, predicted from pressure distribution at the
water surface, are generally in the consensus of the experimental data.
An erratum to this article is available at . 相似文献
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R Malisch 《Zeitschrift für Lebensmittel-Untersuchung und -Forschung》1987,184(6):467-477
Chloramphenicol and meticlorpindol may be determined by HPLC with UV-detection with a limit of 0.02-0.03 mg/kg. Residues of 0.001 mg/kg Chloramphenicol are determined by Capillary-GC with an ECD after an additional clean up step using chromatography on a miniaturized silica column, followed by a silylation step. HMDS/TMCS/Pyridine forms the disilylated Chloramphenicol. In samples of eggs, milk and meat the limit of detection is roughly 0.0002 mg/kg and is adequate to check the FDR tolerance levels for these foods. The proposed method was checked with residues of chloramphenicol in the range of 0.0005 to 0.005 mg/kg in milk from animals dosed with chloramphenicol. Results obtained by this method and results of a RIA-method correlated very well. The analytical procedure (applicable for all substances) was abbreviated compared to the method reported in the first communication on this topic. 相似文献
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