When, for example, Should be put on the refrigerator immediately because some residue may disintegrate when it gets hot, such as insect pesticides will disintegrate faster when there is high temperature.
When the sample should be refrigerated immediately. The residue Some may decompose when heated, such as pesticide will decompose faster in high temperatures.
When the sample should put the refrigerator. Due to some kind of residue may decompose when heated, such as insecticides will decompose faster when in high temperature.