| Chinese herbs in China is rich in resources, the use of Chinese herb for disease treatment and prevention has a long history. With the needs of modernization of Chinese medicine and the extensive application of ultrasonic technology, researches on ultrasonic extraction of Chinese herbs have great influence on promoting the modernization and development of Chinese medicine.Based on Fick's first law and ultrasound effect of breaking plant cells, extracting dynamic equations of mass transfer on ultrasonic extracting herbs has been established. The relationships between the concentration of herbs and extraction time and the concentration of herbs and ultrasonic power have been found. It has been verified by the extraction experiments of extracting Ginkgo flavonoids from Ginkgo leaves and extracting Glycyrrhizin from Licorice.Ginkgo tree is planted in many regions of our country. Ginkgo flavonoids has strong scavenge free radicals and antioxidant activity. In this paper, the experiment of extracting Ginkgo flavonoids from Ginkgo leaves has been completed in two ways. One is using cell disruptor and the other is using ultrasonic cleaning tank. Spectrophotometric standard curve of Ginkgo flavonoids concentration ranging in 12.16-97.28mg/L is set up with Rutin acting as the standard. Ginkgo flavonoids is analyzed and concentration is measured by Al (NO3)3 and NaN02 complexion method, and the results are compared with the soak extraction. The results show that ultrasound strenghs the process of extracting Ginkgo flavonoids from Ginkgo leaves. For the same extraction time, the concentration of Ginkgo flavonoids increases with the ultrasonic power. When the ultrasonic power is fixed, the concentration of Ginkgo flavonoids increases with the extraction time. Under the same extraction conditions, plug-in extraction ways are more efficient than ultrasonic cleaning extraction ways.Licorice is widely used in medicine. Glycyrrhizic acid, an important ingredient in licorice, has anti-virus, anti-thrombosis and other functions. In the Glycyrrhizic extraction experiments, with the use of water as the extraction medium, cell disruptor and ultrasonic cleaning tank is used as extraction equipment. Licorice slices, Licorice fiber and Licorice powder are used to extract Glycyrrhizic from them. Based on a linear relationship between absorbance and concentration of Glycyrrhizic acid in 30%-60% ethanol, spectrophotometric standard curve of concentration ranging in 20-100mg/L is set up. The concentration of the extraction liquid that is obtained under different conditions is measured. The results show that the way of using cell disruptor is more efficient than that of using ultrasonic cleaning and the way of complex extraction is more efficient than others. By comparing the particle shapes and the shapes extracted by ultrasound, we have found that shapes of particle change obviously. The effect of ultrasonic breaking cells is that licorice powder is better than fiber, fiber is better than slices.The analysis of sound field is the theoretical basis for designing and manufacturing ultrasonic extraction equipment. Based on the analysis and vibration calculation function of SYSNOISE and ANSYS software, the sound field of H66MC ultrasonic cleaning tanks working at 39.7KHz is calculated. The sound pressure distribution pictures and laws of the plane located at different distances from bottom are obtained. With the help of the Ultra-PAC ultrasonic C scanning system, the sound field of H66MC ultrasonic cleaning tank is measured and the sound pressure distribution images are obtained, too. Using the PPB US TK ultrasonic energy meter, the sound intensity distribution of the plane located at different distances (1cm,4cm,7cm,10cm,13 cm, 16cm) from bottom is measured with the cleaning tank's power of 100W,200W and 250W; the sound intensity distributions in radiation direction of every transducer are measured; the images of sound intensity distributions are plotted with Matlab, whose results are based on SYSNOISE and ANSYS calculation in accord with the results of measurement.Based on the calculation method of SYSNOISE and ANSYS, the sound pressure distributions of an ultrasonic cleaning tank are calculated under the conditions:different aspect ratio (1:1,2:1,3:2), different rows of transducers settled, and different ways of extraction. The relation between sound field distribution and the influence factors is found. The sound field distributions of cylindrical reactors are calculated as the calculation process as ultrasonic cleaning tank. The results of sound field distribution hereinbefore will provide simulation support for the ultrasonic extraction device designing. The main contributions of this thesis are as follows:(1) Based on the Fick's first law and the effect of ultrasonic breaking plant cells, ultrasonic extraction dynamic equations of mass transfer are established.(2) The experiments of extracting Ginkgo flavonoids from Ginkgo leaves and extracting Glycyrrhizic acid from Licorice, are completed. The ultrasonic extraction dynamic equation is verified.(3) Based on the calculation function of SYSNOISE and ANSYS, the method of sound field calculation is established.(4) The sound fields of the rectangular cleaning tank and the cylindrical reactor are calculated, based on the calculation function of SYSNOISE and ANSYS. The sound field distributions are obtained.
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