无能力之人
发表于 2025-3-25 05:46:56
Spin Hamiltonians,are quadratic with respect to the second quantization operators). We shall also discuss the conditions under which the exact Hamiltonian of a system can be reduced to a spin Hamiltonian of the Heisenberg type, and we shall consider typical spin Hamiltonians.
娘娘腔
发表于 2025-3-25 11:34:40
Method of Approximate Second Quantization,. To do this, it is necessary to know the energy spectrum of the system. The problem of the exact determination of the spectrum of a strongly magnetic substance is very complex and, therefore, we shall consider here a simple method for the approximate determination of the lower part of the energy sp
POLYP
发表于 2025-3-25 11:39:54
Molecular Field Method and Perturbation Theory,sis of some obvious physical considerations, by a Hamiltonian representing the interaction of spins with some effective field (molecular field), which is proportional to the magnetization of the substance. We shall use the theorems relating to the minimum values of the free energy, and thereby we sh
自然环境
发表于 2025-3-25 18:26:04
,Green’s Function Method,idely used in statistical mechanics, because it is an effective means of calculating the observable macroscopic properties of a system as well as the microscopic quantities (for example, the energy and lifetime of elementary excitations). The Green’s function method is also convenient in the calcula
轿车
发表于 2025-3-25 22:47:00
http://reply.papertrans.cn/64/6324/632347/632347_25.png
逃避责任
发表于 2025-3-26 02:02:19
and design.States the recent developments of electrical dri.Recent Developments of Electrical Drives .is composed of the papers which cover a wide spectrum of theory and practice, thus they are deeply rooted in engineering problems, being simultaneously of high theoretical level. This way the conte
Ledger
发表于 2025-3-26 04:39:16
http://reply.papertrans.cn/64/6324/632347/632347_27.png
1FAWN
发表于 2025-3-26 10:32:22
http://reply.papertrans.cn/64/6324/632347/632347_28.png
无动于衷
发表于 2025-3-26 13:57:40
Sergei Vladimirovich Tyablikovre are 57 lakes, that have been created from the final mine voids of a multitude of small-scale opencast mines, varying in size between 0.2 ha and 100 ha. Added to this are lakes that were planned specifically for reasons of landscape preservation in the context of a recultivation scheme (known as l
Pantry
发表于 2025-3-26 18:53:24
Sergei Vladimirovich Tyablikovcal interface, due to relative shear movement in the plane of the discontinuity. The dilatant phenomena will result in displacements in a direction normal to the shear movement and these displacements will be influenced by the elasticity of the geological materials and the compression at the interfa