The beginning of G is false, and B is true in Hong Kong.

The thermos pot is a new product category, which is mainly developed for the inherent characteristics of homes, conferences and other places. Its predecessor evolved from thermos and thermos cup, which can also be called coffee pot.

Modern thermos was invented by British thermos physicist Sir James Dewa in 1892. At that time, he was engaged in the research of liquefied gas. To liquefy gas at low temperature, he first needs to design a container that can isolate the gas from the outside temperature, so he asks the glass technician Berg to blow a double-layer glass container for him, coat the inner walls of the two layers with mercury, and then draw air between the two layers to form a vacuum. This kind of thermos, also called Dupin, can keep the temperature of the liquid in it constant for a certain period of time. Because thermos bottles are mainly used to keep warm hot water at home, they are also called thermos bottles. The structure of thermos bottle is not complicated. There is a double glass bottle liner in the middle. These two layers are evacuated and plated with silver or aluminum. The vacuum state can avoid thermal convection. Glass itself is a poor conductor of heat, and silver-plated glass can reflect the heat energy radiated from the container. On the contrary, if the cold liquid is stored in the bottle, the bottle can prevent the external heat energy from radiating into the bottle. The cork of thermos bottle is usually cork or plastic, both of which are not easy to conduct heat.