广延量的平均值和涨落 =∑(sp,=吉∑(se-zx/a -ka品∑eXo =-kB三0y /alnΞ x-∑x0sk2aw=品是原 △X△Xm=(X-(Xm-Xm)=X7Xm-Xxm=kBav =-kB\aym =-kBayI y 广延量的平均值和涨落 𝑋𝑙 = Õ 𝑠 𝑋𝑙(𝑠)𝑝𝑠 = 1 Ξ Õ 𝑠 𝑋𝑙(𝑠)𝑒 − Í 𝑖 𝑦𝑖𝑋𝑖 (𝑠)/𝑘𝐵 = 1 Ξ Õ 𝑠 (−𝑘𝐵) 𝜕 𝜕𝑦𝑙 𝑒 − Í 𝑖 𝑦𝑖𝑋𝑖 (𝑠)/𝑘𝐵 = 1 Ξ (−𝑘𝐵) 𝜕 𝜕𝑦𝑙 Õ 𝑠 𝑒 − Í 𝑖 𝑦𝑖𝑋𝑖 (𝑠)/𝑘𝐵 = −𝑘𝐵 1 Ξ 𝜕Ξ 𝜕𝑦𝑙 = −𝑘𝐵  𝜕 ln Ξ 𝜕𝑦𝑙  {𝑦𝑖≠𝑙 } 𝑋𝑙𝑋𝑚 = 1 Ξ Õ 𝑠 𝑋𝑙(𝑠)𝑋𝑚(𝑠)𝑒 Í 𝑖 𝑦𝑖𝑋𝑖 (𝑠)/𝑘𝐵 = 𝑘 2 𝐵 1 Ξ 𝜕 2Ξ 𝜕𝑦𝑙𝜕𝑦𝑚 = 𝑘 2 𝐵 𝜕 2 ln Ξ 𝜕𝑦𝑙𝜕𝑦𝑚 + 𝑘 2 𝐵  𝜕 ln Ξ 𝜕𝑦𝑙   𝜕 ln Ξ 𝜕𝑦𝑚  = 𝑘 2 𝐵 𝜕 2 ln Ξ 𝜕𝑦𝑙𝜕𝑦𝑚 + 𝑋𝑙𝑋𝑚 Δ𝑋𝑙Δ𝑋𝑚 = (𝑋𝑙 − 𝑋𝑙) (𝑋𝑚 − 𝑋𝑚) = 𝑋𝑙𝑋𝑚 − 𝑋𝑙𝑋𝑚 = 𝑘 2 𝐵 𝜕 2 ln Ξ 𝜕𝑦𝑙𝜕𝑦𝑚 = −𝑘𝐵  𝜕𝑋𝑙 𝜕𝑦𝑚  {𝑦𝑖≠𝑚} = −𝑘𝐵  𝜕𝑋𝑚 𝜕𝑦𝑙  {𝑦𝑖≠𝑙 }