中文摘要：

本文根据已证明了的光谱等效温度Tλ方程和光量子能量，首次导出了光量子熵常数sλ为3．72680×10^-23J·K^-1，并证明通过sλ算出的黑体等效温度等于黑体辐射温度，验证了光量子熵常数结论的正确性；此外，给出了闭口系平衡态空腔辐射场光子气的熵和熵变方程，首次提出开口系辐射流的熵，接收器的净辐射熵差的计算式。本文的结果，为非平衡态辐射热力学体系提供了新的理论基础，对研究辐射能与其它能量转化中不可逆损失将提供有益帮助。

英文摘要：

Using the proved equation of spectral effective temperature Tλ and photon energy, the entropy constant of the photon is educed to be 3.72680× 10^-23J·K^-1 for the first time. The blackbody effective temperature educed from sλ is proved to be equal to the blackbody radiation temperature, which validated the correctness of the photon entropy constant. Furthermore, the entropy and entropy equation of photon gas in the equilibrious radiation field in a closed cavum is got. The entropy of radiant flow in an open system and the formula for calculating the net entropy received by the receiver are presented for the first time. The paper provides a new theoretical basis for non-equilibrium thermodynamics system, and can help to study the irreversible loss during conversions of radiation energy to other energy.