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25 March 2022, Volume 39 Issue 2 Previous Issue    Next Issue
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Review Article

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Progress in the Study of Deuteron-Triton Fusion Cross Sections in Superintense Laser Fields Wenjuan LYU, Binbing WU, Shiwei LIU, Hao DUAN, Jie LIU 2022, 39(2): 127-142.  DOI: 10.19596/j.cnki.1001-246x.8388 Abstract ( )   HTML ( )   PDF (11679KB) ( )   Development of superintense laser technology has brought historic opportunities and space to expand for the study of interaction between light and matter. The process of nuclear reaction assisted by superintense laser field, especially the influence on cross sections of deuteron-triton fusion reaction, has attracted more and more attention. In this paper, we introduce the rapid development of laser technology and the wide application of superintense laser technology. Then we introduce the cross sections of nuclear fusion reaction and its influencing factors, and review recent progress in the study of light nuclear fusion cross sections in superintense laser field with emphasis on deuteron-triton fusion reaction. At last, we make some prospects for future development in this direction.

Research Reports

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A Parallel SN Method for Neutron Transport Equation in 2-D Spherical Coordinate Ying CAI, Cunbo ZHANG, Xu LIU, Zhengfeng FAN, Yuanyuan LIU, Xiaowen XU, Aiqing ZHANG 2022, 39(2): 143-152.  DOI: 10.19596/j.cnki.1001-246x.8381 Abstract ( )   HTML ( )   PDF (5045KB) ( )   Targeting at SN algorithm for the neutron transport equation in the two-dimensional spherical coordinate system, we propose a directed graph model based on a (cell, direction) two-tuple, and design a multi-level parallel SN algorithm with controllable granularity on the basis of the existing parallel pipeline algorithm based on directed graph. Among them, a combination of domain decomposition and parallel pipeline is used to mine parallelism in the space-angle direction, and an energy group pipeline parallel method is proposed. Furthermore, by setting appropriate pipeline granularity, the overhead of scheduling, communication and idle waiting are well balanced. Experimental results show that the algorithm can effectively solve the neutron transport equation in the two-dimensional spherical coordinate system. For a typical neutron transport problem with 960 000 grids, 60 directions, 24 energy groups, and billions of degrees of freedom, the parallel program achieved 71% parallel efficiency on 1920 cores of a domestic parallel machine.

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A Three-dimensional Neutron Diffusion Nodal Solver Based on 2D Generic Transverse Integrate Fused with 1D Semi-analytical Nodal Method Zhiyong LI 2022, 39(2): 153-158.  DOI: 10.19596/j.cnki.1001-246x.8377 Abstract ( )   HTML ( )   PDF (811KB) ( )   The nodal expansion method (NEM) based on transverse integrated technique is widely used in liquid water reactor core design. It uses an empirical transverse leakage polynomial approximation. Furthermore, it requires pin power reconstruction model for pin power within the assembly. A generic transverse integrate proposed in this work avoids the above shortages. Since the core heterogeneous usually happens in radial direction, the 3D neutron diffusion equation is solved with 2D generic transverse integrate fused with traditional 1D semi-analytical nodal method. With IAEA 2D/3D benchmark problem, the method is demonstrated correct and feasible for core neutron diffusion calculations.

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Structural Stability and Anharmonic Effect of Metallic Hydrogen FCC Phase Under High Pressures Xiaohui WANG, Ping ZHANG 2022, 39(2): 159-164.  DOI: 10.19596/j.cnki.1001-246x.8401 Abstract ( )   HTML ( )   PDF (5180KB) ( )   First principles molecular dynamics calculation is used to study anharmonic effect of metallic hydrogen system. Lattice vibrations of metallic hydrogen are given, and temperature effect of phonon spectrum of metallic hydrogen is discussed. Phonon dispersions of FCC phases of protium, deuterium and tritium at non-zero temperature were given. Comparing phonon dispersions at different temperatures, we found that 3.6 TPa is the critical pressure of thermodynamic stability at zero temperature, while the critical pressure dropped to 2.8 TPa at a finite temperature (100 K). Anharmonic effect changes significantly stability and phonon dispersions of the system.

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Quantum Discord of Heisenberg XYZ Spin Chain in Non-Markovian Environment Shisheng TANG, AHMAT Abliz 2022, 39(2): 165-172.  DOI: 10.19596/j.cnki.1001-246x.8393 Abstract ( )   HTML ( )   PDF (2282KB) ( )   We study dynamical evolution of quantum discord of a two-bit anisotropic Heisenberg XYZ model in a cosine magnetic field using a quantum discord method. With the maximum entangled state $\left|\psi_{A B}\right\rangle=(1 / \sqrt{2})(|11\rangle+|00\rangle)$ as the initial state of the Heisenberg XYZ spin chain, the non-Markovian master equation is solved analytically with the non-Markovian quantum state diffusion method and the reduced density matrix of anisotropic Heisenberg XYZ is obtained; Then we bring it into the quantum discord formula to derive evolution dynamics of quantum discord of the system. It is found that as the environmental correlation coefficient γ is small, quantum discord of the system obviously shows an upward trend. It shows that the non-Markovian environment has a positive effect on the quantum discord of the system. Greater spin coupling coefficient J, JZ and cosine magnetic field intensity increase the quantum discord as well.

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Analysis of Optical Power Limit of Injection Fiber for Long Distance Transmission of High Power Laser in Single Mode Fiber Hualong YU, Shiyu WANG, Jiachen WU 2022, 39(2): 173-178.  DOI: 10.19596/j.cnki.1001-246x.8373 Abstract ( )   HTML ( )   PDF (3913KB) ( )   For long-distance transmission of high-power laser in single-mode fiber, traditional Raman scattering (SRS) threshold is used as the laser power of the injected fiber, which is too large. In this paper, the variation of pump and Stokes power with laser power of injected fiber of high-power laser over long-distance single-mode fiber is simulated and analyzed theoretically. According to the mechanism of SRS generation in the fiber, optical power limit of injected fiber suitable for high-power laser over long-distance single-mode fiber is proposed. The limit of injected laser power corresponds to the maximum curvature point of the power curve of Raman Stokes light propagating in a single-mode fiber. The variation of optical power limit with fiber length is simulated and a formula of laser power limit of single-mode fiber is obtained with curve fitting. Experimental results show that the formula is suitable for high-power laser over long-distance single-mode fiber.

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Reducing Entropy Production in a Lagrangian Method Liji WANG, Hongping GUO, Zhijun SHEN 2022, 39(2): 179-190.  DOI: 10.19596/j.cnki.1001-246x.8384 Abstract ( )   HTML ( )   PDF (8475KB) ( )   We investigate entropy production in a cell centered Lagrangian method. The motivation is to reduce intrinsic entropy dissipation of a Godunov method in calculating isentropic flow problems. By implementing pressure modification to the original scheme, a flux fix approach is proposed based on the fully discrete entropy inequality. Numerical experiments show that for problems with expansion waves the modified flux algorithm has better solution behaviors than the original Lagrangian method.

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FTM Numerical Simulation of Point Heat Source in Marangoni Without Gravity Mengying SUN, Ming MA, Hailong GUO, Mengjun YAO, Meng XU, Ying ZHANG 2022, 39(2): 191-200.  DOI: 10.19596/j.cnki.1001-246x.8395 Abstract ( )   HTML ( )   PDF (7219KB) ( )   Front-tracking method (FTM) is used to study droplet motion caused by Marangoni effect with a point heat source in the diagonal direction. Droplet motion at different Marangoni (Ma) numbers was simulated. It was found that the droplet velocity which decreases as Ma number increasing, increases rapidly to a stable migration velocity then decreases. However, it reverses at t=1.2, which increases as Ma number increasing. Whereupon, the vortex of Hill sphere split and the vortex center moved slightly. The same reflux exists in the droplet as in the Hill sphere vortex. With the increasing of Ma, end topology of temperature field bifurcates twice: The lowest temperature point jumps into the droplet from the stagnation point when occurs firstly in the lower critical Ma number; The inner shell cooling zone breaks from the central point when occurs secondly at upper, then forming toroidal cooling zone.

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Application of Grey System Theory in Approximate Calculation of Wave Packet Evolution Jiayu NI, Dehong GAO, Linfeng YE, Xiangdong FENG 2022, 39(2): 201-211.  DOI: 10.19596/j.cnki.1001-246x.8361 Abstract ( )   HTML ( )   PDF (6012KB) ( )   Based on the grey system theory, we replace the time response function of GM (1, 1) model for wave packet distribution, and obtain simulated evolution behavior of wave packet's wave function with mathematical techniques such as variational method, and make error analysis and correction. In practical applications, the approximate evolution behavior of wave function can be obtained with parameters of its development coefficient. Gaussian wave packet is taken as an example to show the method. The grey system theory in mathematical modeling is introduced into the calculation of physics, and an approximate calculation method is provided, which can be used in the calculation of wave packet evolution.

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Site-bond Percolation Modeling of Real Networks: Generating Function Method Tao FU, Long WU, Chenguang LI 2022, 39(2): 212-222.  DOI: 10.19596/j.cnki.1001-246x.8362 Abstract ( )   HTML ( )   PDF (1334KB) ( )   We propose a site-bond percolation model based on generating function method, and then apply it to four representative concrete networks to observe accuracy of its estimates. Finally, we discuss causes of the inaccuracy and give simple applications. Our site-bond percolation model could be used to anticipate the connectivity of various real networks after site and bond attack and study their entire robustness. Process procedure of the model is simple, and the accuracy of its estimates is acceptable compared with that calculated with the message passing algorithm. Meanwhile, its calculation time is much lower than that of the information passing algorithm. Therefore, it has good application potential.

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A Compound Neural Network for Learning Partial Differential Equations from Noisy Data Jian PAN, Zhaoli GUO, Songze CHEN 2022, 39(2): 223-232.  DOI: 10.19596/j.cnki.1001-246x.8364 Abstract ( )   HTML ( )   PDF (9193KB) ( )   A compound neural network method, NN-PDE(neural network-partial differential equations), is proposed for data preprocessing and learning partial differential equation. NN-PDE uses one sub network to preprocess noisy data, and another one to couple information of the alternative equations to learn the underlying governing equation. These two sub networks are merged into one compound network so that it can process noisy data more efficiently and effectively to reduce the influence of noise. Noisy data generated from various physical equations (such as Burgers equation, Korteweg-de Vries(KdV) equation, Kuramoto-Sivashinsky(KS) equation and Navier-Stokes(NS) equation) are studied with NN-PDE, and accurate governing equations are obtained.

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Analysis of Braess Paradox in an Interconnected Power Grid Based on Complex Network Theory Shaoze ZHANG, Yanli ZOU, Shuyi TAN, Haoqian LI, Xinyan LIU 2022, 39(2): 233-243.  DOI: 10.19596/j.cnki.1001-246x.8387 Abstract ( )   HTML ( )   PDF (10803KB) ( )   To explore Braess paradox phenomenon in an interconnected power grid, a second order Kuramoto-like phase oscillator model is applied to model dynamics of the power grid. The two subnets are connected by the largest degree nodes to build an interconnected power grid. As power transmission between two subnets occurs, new transmission lines are added in the two subnets repectively to explore the probability of Braess paradox phenomenon and analyze the reasons. It is found that as the power transmission between the two subnets reaches a critical value, synchronizability of the power receiving subnet is much better than that of the power supply subnet. The probability of Braess paradox caused by adding a new transmission line in the power supply subnet is much higher than that caused by adding a new transmission line in the power receiving subnet. The phenomena are analyzed in depth by defining subnet order parameter. This study is important for the topology optimization of a interconnected power grid.

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Dynamical Analysis and Circuit Implementation of a Memristive Hopfield Neural Network Lihong TANG, Zongmei HE, Yanli YAO 2022, 39(2): 244-252.  DOI: 10.19596/j.cnki.1001-246x.8386 Abstract ( )   HTML ( )   PDF (7314KB) ( )   An extremely multistable memristive Hopfield neural network (HNN) is proposed which includes only three neurons and one multistable memristor synapse. Dissipativity and stability of equilibrium points are theoretically analyzed, and influence of memristive synapse-coupled strengths on dynamics in the memristive neural network is analyzed with numerical methods such as bifurcation diagrams, Lyapunov exponents, and phase plots. As network parameters are fixed, dynamical behavior of extreme multistability related to initial states is revealed. Finally, analog equivalent circuit of the memristive HNN is designed, and MATLAB numerical simulation results are verified with PSIM circuit simulation.