infrared portion的用法和樣例：
例句
- The range of the spectrum in which heat is radiated mostly lies within the infrared portion.
輻射熱的光譜段大部分落在紅外區。 - This expansion causes changes in the character of the emission over time, resulting in the time delay between the infrared and sub-millimetre flares.
這種膨脹導致了輻射的性質隨著時間變化，結果就是紅外波段和亞毫米波段的閃耀時延。
