It can be used for building exterior wall thermal insulation owing to its excellent thermal insulation, good construction workability and low cost.

该保温砂浆保温性能优良，施工和易性好，成本较低，可用于建筑外墙保温。

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This approach is described as a "passive" system because once initial conditions are set inside the flask, a continuing presence of helium and good insulation is all that is required to maintain those conditions.

BBC: Herschel space telescope finishes mission