| Ice formation inside or outside cells has been proposed to be a factor causing cryoinjury to cells or tissues during cryopreservation. How to control, reduce or eliminate the ice formation has been an important research topic in fundamental cryobiology.Common methods used to achieve vitrification involve the use of either an ultrarapid cooling rate or a very high concentration of cryoprotectants. Unfortunately, an ultrarapid cooling rate is very difficult to attain, introduction of high concentration of cryoprotectants can directly damage cells and tissues. For these reasons it is desirable to develop novel technologies to vitrify biomaterials using achievable cooling rates.The magnetic generator making and the effects of low-frequent magnetic field on the ice formation are discussed in this paper. The self-made magnetic generator, which is composed of an oscillator, a second-order system, a scaler, a decoder, a circuit and Helmholtz-loops, account for designing and tailing a second-order system especially, which using switch capacitance technic implement tracking signal.During performance, applies low-frequent magnetic field on the KMnO4 solution with a concentration of 0.9% selected as sample during performance. A self-made cooling device for temperature control is used to measure the temperature of the solution during ice formation at low temperatures. The whole process of the solution icing and the shapes of ice crystals formed in alternating magnetic fields of different frequencies and intensities are observed, to explore the relationship between ice formation, and magnetic conditions and cooling speed, to find out a best electromagnetic control parameter for the vetrification of the solution. While analyzing to experiment the phenomenon, dielectric polarization and dissipative mechanism are used for qualitative analysis, then put forward the frequency wave segment of eddy magnetic, which is likely to working on ice crystal's vegetal.
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