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271.
The generation and behavior of ultrasonic standing waves was modeled using the light cut method for transparent fluid. The oscillations of the fluid surface in initial moment of switching on ultrasound and appearance of standing wave channel were observed. The effect of continuous fluid depth decrease and increase on the behavior of ultrasonic standing wave channel was studied. The ultrasonic standing wave channel floated in the liquid between of the crucible bottom and fluid surface and discretely changed its height by half ultrasonic wavelength with the decrease or increase of the liquid level. This channel had the behavior of a “quasi solid state” and damped of convection. 相似文献
272.
Espinosa-Solares T Morales-Contreras M Robles-Martínez F García-Nazariega M Lobato-Calleros C 《Applied biochemistry and biotechnology》2008,147(1-3):133-142
Agro-food industrial processes produce a large amount of residues, most of which are organic. One of the possible solutions
for the treatment of these residues is anaerobic digestion in bioreactors. A novel 18-L bioreactor for treating waste water
was designed based on pneumatic agitation and semispherical baffles. Flow patterns were visualized using the particle tracer
technique. Circulation times were measured with the particle tracer and the thermal technique, while mixing times were measured
using the thermal technique. Newtonian fluid and two non-Newtonian fluids were used to simulate the operational conditions.
The results showed that the change from Newtonian to non-Newtonian properties reduces mixed zones and increases circulation
and mixing times. Circulation time was similar when evaluated with the thermal and the tracer particle methods. It was possible
to predict dimensionless mixing time (θ
m) using an equivalent Froude number (Fr
eq). 相似文献
273.
《Analytical letters》2012,45(7-8):539-550
Abstract A sensitive, rapid, and specific high pressure liquid chromatographic (HPLC) assay was developed for the determination of salicylic (SA) and salicyluric (SU) acids in plasma and urine. The compounds are extracted into ethyl ether at acid pH, evaporated, and reconstituted prior to instrumental separation. Overall recovery of both compounds is 90 ± 5%, and the sensitivity limits are 150 ng of SU and 300 ng SA per ml of biological fluid. The assay was used for the determination of both compounds in plasma and urine of man following oral doses of 40 mg/kg of sodium salicylate. 相似文献
274.
This paper is an analytical study of the rotating flow of a third grade fluid past a porous plate with partial slip effects. It serves as a flow model for the study of polymers. The analytic solution has been determined using homotopy analysis method (HAM).The English text was polished by Yunming Chen. 相似文献