Sample cooling and storage method

A sample cooling and storage method, comprising a step of placing samples into a liquid nitrogen storage box, wherein in the sample cooling and storage method, the samples are raised and lowered in the liquid nitrogen storage box via a lifting device, undergo programmed cooling and then directly stored in the liquid nitrogen storage box after the programmed cooling, and a method of the programmed cooling comprises the following steps:

• dividing the programmed cooling into several stages of cooling which correspond to a standard ambient cooling curve and are performed in sequence, wherein each stage of cooling comprises the following steps:
• S1:
• setting a target ambient temperature w according to the standard ambient cooling curve;
• S2:
• acquiring an actual ambient temperature T1;
• and
• S3:
• comparing the target ambient temperature w with the actual ambient temperature T1 and controlling raising and lowering of the samples;
• lowering the samples by a first predetermined height if the target ambient temperature w is higher than the actual ambient temperature T1;
• raising the samples by a second predetermined height if the target ambient temperature w is lower than the actual ambient temperature T1;
• determining whether the actual ambient temperature T1 is equal to a target temperature T2 in this stage of cooling if the target ambient temperature w is equal to the actual ambient temperature T1;
• ending this stage of cooling if the actual ambient temperature T1 is equal to the target temperature T2 in this stage of cooling at the moment;
• and
• cyclically performing step S1 to step S3 if the actual ambient temperature T1 is not equal to the target temperature T2 in this stage of cooling at the moment, until the actual ambient temperature T1 is equal to the target temperature T2 in this stage of cooling.