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1.
By constructing close-one-cochain density Ω^12n in the gauge group space we get the Wess-Zumino-Witten (WZW) effective Lagrangian on high-dimensional noncommutative space.Especially consistent anomalies derived from this WZW effective action in noncommutative four-dimensional space coincide with those obtained by L.Bonora etc.(het-th/0002210). 相似文献
2.
Using an integral-equation approach based upon an approximation for the tail function, the equilibrium properties of a system of hard spheres are studied with special concern for the behavior in the region of close packing. The closure adopted is such that full, internal consistency is ensured in the thermodynamics of the model with respect to both the two zero-separation theorems as well as to the more standard virial and fluctuation routes to the equation of state. The scheme also makes use of the continuity properties of the tail function and of the cavity distribution function at contact. These properties are explictly tested in the low-density limit up to the fourth derivative. The theory generates an equilibrium branch bounded on the high-density side by a point corresponding to a packing fraction0.78, a value which closely matches Rogers' least upper bound for the densest packing of spheres. The pair structure of the fluid in the state of random close packing is also compared to the type of local order predicted by the theory at similar densities. 相似文献
3.
平面应力条件下闭合断续节理岩体力学特性试验研究 总被引:4,自引:0,他引:4
通过平面应力条件下闭合断续节理岩体的破坏试验,采用自行研制的高压柔性加载装置施加垂向和侧向荷载,用千分表和激光散斑照相技术量测试体位移场,用应变花量测试体平面应力场. 结果表明,激光散斑法用于测定闭合断续节理岩体的位移场效果良好,其测值比对应点千分表测值偏小14% 左右.据所测得的位移场和应力场,研究了裂纹尖端应力场的演变及裂纹扩展的路径,分析了试体的变形和破坏特征,测定了翼裂纹初裂角,探讨了试体的破坏机理. 相似文献
4.
The channelling of 3 MeV protons in the 〈110〉 direction of silicon has been simulated using Vineyard model taking into account
thermally vibrating nuclei and energy loss due to ion-electron interactions. A beam made up of constant energy particles but
with spatial divergence has been simulated for the purpose. The values of the minimum scattering yield and half width of the
channelling dip are shown to be depth sensitive and agree well with the measured values. The dependence of yield on the angle
of incidence has been found to give information of all three types of channelling. The critical angles for the three types
of channelling and wavelength of planar oscillations are consistent with the previous calculations. 相似文献
5.
S. Redner 《Journal of statistical physics》1981,25(1):15-23
We study the ground state properties of a one-dimensional Ising chain with a nearest-neighbor ferromagnetic interactionJ
1, and akth neighboranti-ferromagnetic interactionJ
k
. WhenJ
k/J1=–1/k, there exists a highly degenerate ground state with a residual entropy per spin. For the finite chain with free boundary conditions, we calculate the degeneracy of this state exactly, and find that it is proportional to the (N+k–1)th term in a generalized Fibonacci sequence defined by,F
N
(k)
=F
N–1
(k)
+F
N–k
(k)
. In addition, we show that this one-dimensional model is closely related to the following problems: (a) a fully frustrated two-dimensional Ising system with a periodic arrangement of nearest-neighbor ferro- and antiferromagnetic bonds, (b) close-packing of dimers on a ladder, a 2× strip of the square lattice, and (c) directed self-avoiding walks on finite lattice strips.Work partially supported by grants from AFOSR and ARO. 相似文献
6.
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9.
An analytic expression of the potential energy surface (PES) of the ground state of the Ne-HF complex is obtained by utilizing
nonlinear least square method to fit the intermolecular interaction energies [Zhang Y. Guizhou Science, 2003, 21(3): 9–13 (in Chinese)], which have been computed using the augmented correlation-consistent polarized quadruple
zeta basis set aug-cc-pVQZ at the theoretical level of CCSD (T). On the basis of the PES, the partial cross sections (PCSs)
at the incident energies of 60, 75, 100 and 150 meV for collisions between Ne atoms and HF molecules are calculated using
the quantum close coupling approach. The effects of the long-range attractive and the short-range anisotropic interactions
on the inelastic PCSs are discussed in detail. The results show: (1) The long-range attractive well of the EPS makes the significant
contribution to the lower excitation PCSs, especially the tail maximum for j = 0→j′ = 1 transitions, whereas no contribution is to the j′⩾3 inelastic transitions. (2) The short-range (the repulsive and attractive) interaction makes the significant contribution
to the lower excitation PCSs, especially the main peak for j = 0→j′ = 1, 2. As for the transitions of j′⩾3, the short-range interaction plays a key role in the inelastic excitation. (3) Although the positions of the maximums
and minimums of the inelastic PCSs are different at the collision energies, they correspond to almost the same impact parameter.
Supported by the National Natural Science Foundation of China (Grant Nos. 10676025 and 10574096) 相似文献
10.