激波管聚酯膜片变形过程分析

使用聚酯薄膜作为激波管膜片,通过施加不同压力的激波管实验,获得了膜片厚度及多张膜片的组合方式对膜片所能承受最大压力的影响。利用高速相机对激波管膜片从开始变形到破坏的全过程进行拍摄,使用三维DIC软件获得膜片在变形过程中的位移场。实验发现了膜片会出现圆弧反翘并快速破坏的特别现象,并以此为特征将变形过程分为2个阶段。给出任意厚度膜片第1阶段圆弧变形的数学规律及第2阶段圆弧反翘的形状特征,以及全过程中膜片厚度变化的数学规律。     

考虑横向剪切变形和旋转惯性的层合正交异性球壳的动态响应

本文建立了计及横向剪切变形的旋转惯性的复合材料轴对称层合圆柱正交异性球壳的运动方程。在此基础上，用有限差分法计算了球壳在轴对称动力载荷下的动态响应，并讨论了材料参数、结构参数和横向剪切变形的影响。     

Propagation of Plane Waves of a Defect Field in a Viscoplastic Medium in the Presence of an Interface between Two Media

The dynamic equations of the continual theory of defects are used to study the structure of the waves of a defect field characterized by a defect density tensor and a defect flux tensor in a viscoplastic medium. Relations are obtained that define the passage of defect field waves through an interface between two media. Particular cases of media with rapidly and slowly decaying waves are considered.     

Numerical investigation on detonation cell evolution in a channel with area-changing cross section

The two-dimensional cellular detonation propagating in a channel with area- changing cross section was numerically simulated with the dispersion-controlled dissipative scheme and a detailed chemical reaction model. Effects of the flow expansion and compression on the cellular detonation cell were investigated to illustrate the mechanism of the transverse wave development and the cellular detonation cell evolution. By examining gas composition variations behind the leading shock, the chemical reaction rate, the reaction zone length, and thermodynamic parameters, two kinds of the abnormal detonation waves were identified. To explore their development mechanism, chemical reactions, reflected shocks and rarefaction waves were discussed, which interact with each other and affect the cellular detonation in different ways.     

Transverse momentum spectra in high-energy nucleus-nucleus, proton-nucleus and proton-proton collisions

The transverse momentum distributions of final-state particles produced in nucleus-nucleus (AA), proton-nucleus (pA), and proton-proton (pp) collisions at high energies are investigated using a multisource ideal gas model. Our calculated results show that the contribution of hard emission can be neglected in the study of transverse momentum spectra of charged pions and kaons produced in Cu-Cu collisions at √s_NN=22.5 GeV. And if we consider the contribution of hard emission, the transverse momentum spectra of p and p produced in Cu-Cu collisions at √s_NN=22.5 GeV, K_s⁰ produced in Pb-Pb collisions at 158 A GeV, J/ψ particles produced in p-Pb collisions at 400 GeV and π⁺ , K⁺, p produced in proton-proton collisions at √s=200 GeV, can be described by the model, especially in the tail part of spectra.     

随机横场与晶场作用混合自旋系统的热力学性质

利用有效场理论和切断近似，在伊辛模型的框架内考虑随机横场与晶场作用的混合自旋1/2 和自旋1系统的热力学性质。重点研究了晶场、横场和随机浓度对混合自旋系统相变的影响 ，研究发现在随机横场条件下，较小的晶场存在并不能改变临界横场阈值；取较大横场值时 在某些随机浓度的范围内出现重入相变现象，而取较小横场值时则没有出现重入相变现象。 给出了有关相图并进行了讨论。 关键词： 混合自旋系统 伊辛模型 热力学性质 随机横场     

Magnetic properties of a hexagonal transverse Ising nanoisland

The magnetic properties of a hexagonal transverse Ising nanoisland have been calculated by the effective-field theory with correlations. The effects of surface coupling, interlayer coupling, and the competition between transverse fields at the surface shell and in the inner core on phase diagrams and magnetizations are examined. Meanwhile, the results are also compared with two different nanoislands which consist of two layers with nine atoms or five atoms in each of the layers.     

粘弹层合板的自由振动和横向应力

Based on Reddy＇s layerwise theory, the governing equations for dynamic response of viscoelastic laminated plate are derived by using the quadratic interpolation function for displacement in the direction of plate thickness. Vibration frequencies and loss factors are calculated for free vibration of simply supported viscoelastic sandwich plate, showing good agreement with the results in the literature. Harmonious transverse stresses can be obtained. The results show that the transverse shear stresses are the main factor to the delamination of viscoelastic laminated plate in lower-frequency free vibration, and the transverse normal stress is the main one in higher-frequency free vibration. Relationship between the modulus of viscoelastic materials and transverse stress is analyzed. Ratio between the transverse stress＇s maximum value and the in-plane stress＇s maximum-value is obtained. The results show that the proposed method, and the adopted equations and programs are reliable.     

Excitation Functions of Tsallis-Like Parameters in High-Energy Nucleus–Nucleus Collisions

The transverse momentum spectra of charged pions, kaons, and protons produced at mid-rapidity in central nucleus–nucleus (AA) collisions at high energies are analyzed by considering particles to be created from two participant partons, which are assumed to be contributors from the collision system. Each participant (contributor) parton is assumed to contribute to the transverse momentum by a Tsallis-like function. The contributions of the two participant partons are regarded as the two components of transverse momentum of the identified particle. The experimental data measured in high-energy AA collisions by international collaborations are studied. The excitation functions of kinetic freeze-out temperature and transverse flow velocity are extracted. The two parameters increase quickly from ≈3 to ≈10 GeV (exactly from 2.7 to 7.7 GeV) and then slowly at above 10 GeV with the increase of collision energy. In particular, there is a plateau from near 10 GeV to 200 GeV in the excitation function of kinetic freeze-out temperature.     

手征和运动介质界面异常光自旋霍尔效应

文章讨论了偏振高斯光束在空气-手征介质界面的反射和折射问题,发现了反射和折射光束的异常自旋霍尔效应.在某些特定的角度下,反射高斯光束重心的移动可以达到几十个波长的量级,通过调节手征参数,甚至会出现折射光重心移动方向由正到负的转变.文章还讨论了任意偏振高斯光束在空气-运动介质界面的反射和透射问题,当介质垂直于入射平面运动时,反射和透射光束的横向移动可以达到几个波长的量级,甚至在某些运动速度下可以实现移动方向正负的改变.这些研究对控制光的自旋霍尔效应提供了可能的途径.