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第285行： − 当今非平衡态热力学的范围并不包括所有的物理过程。在物质的非平衡态热力学几年，许多研究有效的一个条件是，他们处理的是所谓的局部热力学平衡。+ 第294行：
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→Local thermodynamic equilibrium
==Local thermodynamic equilibrium==
==Local thermodynamic equilibrium==
局部热力学平衡
The scope of present-day non-equilibrium thermodynamics does not cover all physical processes. A condition for the validity of many studies in non-equilibrium thermodynamics of matter is that they deal with what is known as ''local thermodynamic equilibrium''.
The scope of present-day non-equilibrium thermodynamics does not cover all physical processes. A condition for the validity of many studies in non-equilibrium thermodynamics of matter is that they deal with what is known as ''local thermodynamic equilibrium''.
The scope of present-day non-equilibrium thermodynamics does not cover all physical processes. A condition for the validity of many studies in non-equilibrium thermodynamics of matter is that they deal with what is known as local thermodynamic equilibrium.
The scope of present-day non-equilibrium thermodynamics does not cover all physical processes. A condition for the validity of many studies in non-equilibrium thermodynamics of matter is that they deal with what is known as local thermodynamic equilibrium.
目前非平衡态热力学的范围并不包括所有的物理过程。在物质的非平衡态热力学中，许多研究有效的一个条件是，他们处理的是所谓的局部热力学平衡。
Local thermodynamic equilibrium of matter (see also Keizer (1987) means that conceptually, for study and analysis, the system can be spatially and temporally divided into 'cells' or 'micro-phases' of small (infinitesimal) size, in which classical thermodynamical equilibrium conditions for matter are fulfilled to good approximation. These conditions are unfulfilled, for example, in very rarefied gases, in which molecular collisions are infrequent; and in the boundary layers of a star, where radiation is passing energy to space; and for interacting fermions at very low temperature, where dissipative processes become ineffective. When these 'cells' are defined, one admits that matter and energy may pass freely between contiguous 'cells', slowly enough to leave the 'cells' in their respective individual local thermodynamic equilibria with respect to intensive variables.
Local thermodynamic equilibrium of matter (see also Keizer (1987) means that conceptually, for study and analysis, the system can be spatially and temporally divided into 'cells' or 'micro-phases' of small (infinitesimal) size, in which classical thermodynamical equilibrium conditions for matter are fulfilled to good approximation. These conditions are unfulfilled, for example, in very rarefied gases, in which molecular collisions are infrequent; and in the boundary layers of a star, where radiation is passing energy to space; and for interacting fermions at very low temperature, where dissipative processes become ineffective. When these 'cells' are defined, one admits that matter and energy may pass freely between contiguous 'cells', slowly enough to leave the 'cells' in their respective individual local thermodynamic equilibria with respect to intensive variables.
物质的局部热力学平衡(参见 Keizer (1987))意味着，从概念上来说，为了研究和分析，系统可以在空间上和时间上分为小(无限小)尺寸的‘细胞’或‘微相’ ，在这种情况下，物质的经典热力学平衡条件得到了很好的近似。例如，在非常稀薄的气体中，分子碰撞很少发生; 在恒星的边界层中，辐射将能量传递到空间; 在非常低的温度下，相互作用的费米子中，耗散过程变得无效。当这些细胞被定义时，人们承认物质和能量可以在相邻的细胞之间自由通过，慢到足以让细胞在它们各自关于强化变量的局部热力学平衡中离开。
物质的局部热力学平衡(参见 Keizer (1987))意味着，从概念上来说，为了研究和分析，系统可以在空间和时间上分割为小(无限小)尺寸的‘细胞’或‘微相’ ，每个微元中物质的经典热力学平衡条件得在很好的近似下得以满足。经典热力学平衡条件对系统整体可能不能满足，例如在非常稀薄的气体中，分子碰撞很少发生; 在恒星的边界层中，辐射将能量传递到空间; 在非常低的温度下相互作用的费米子中，耗散过程变得无效。但是当我们定义这些“细胞”时，人们承认物质和能量可以在相邻的“细胞”之间自由通过，慢到足以在它们各自关于强度量的局部热力学平衡中离开“细胞”。
考虑到恒星，Edward a. Milne 给出了局部热力学平衡的定义，即每个局部细胞中物质的热辐射。他定义了细胞中的局部热力学平衡，要求它在宏观上吸收和自发放射辐射，就好像它处于细胞物质温度的辐射平衡中一样。然后严格遵守基尔霍夫辐射发射率和吸收率相等的定律，使用一个黑体源函数。这里局域热力学平衡的关键在于，可重物质粒子的碰撞速率，比如分子，应该远远超过光子的产生和湮灭速率。
考虑到恒星，Edward a. Milne 给出了局部热力学平衡的定义，即每个局部细胞中物质的热辐射。他定义了细胞中的局部热力学平衡，要求它在宏观上吸收和自发放射辐射，就好像它处于细胞物质温度的辐射平衡中一样。然后严格遵守基尔霍夫辐射发射率和吸收率相等的定律，使用一个黑体源函数。这里局域热力学平衡的关键在于，可重物质粒子的碰撞速率，比如分子，应该远远超过光子的产生和湮灭速率。
==Entropy in evolving systems==
==Entropy in evolving systems==