如果水是凉的，而空气是暖的，并伴有太阳，此时花费较长的时间入水是可以的，因为你的身体没有散失热量。

If the water is cold but the air is warm, and sun is shining, it's OK to take longer getting in since your body's not losing heat.

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浸泡在冷水中导致热量迅速散失。

Immersion in cold water resulted in rapid loss of heat.

《牛津词典》

举个例子来说，假如住宅的窗户没有进行恰当的隔热处理，或是不能在防止热量散失的同时阻挡紫外线，利用太阳电池板取暖的效力就会大大减弱。

For example, heating a home using solar panels becomes much less effective if the Windows in the house are not properly insulated or treated to keep the heat in and the UV rays out.

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