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In order to obtain the failure characteristics of pipe surface under the shock wave action of gas explosion, the physical and mathematical model of gas explosion in pipe were established by LS-DYNA software, and the shock failure characteristics of pipe surface with different radii under gas explosion were simulated, the radius is 0.4 m, 0.6 m, 0.8 m and 1.0 m, respectively. Results showed that with the increase of the radius, the duration of the pressure "platform" in the measuring point A and B is obviously shortened, fluctuation range produced by the pressure curves in measuring points C, D, E and F change less, but their fluctuation time is shortened. The explosion pressure increases and the failure degree increases with increase of the radius. Finally, the influence of scale effect of gas explosion and its propagation process on gas explosion propagation parameters is obtained. The research results have some guiding effects on gas explosion and disaster prevention.

The multinucleon transfer reaction of Xe136+198Pt at Elab=7.98 MeV/nucleon is investigated by using the improved quantum molecular dynamics model. The quasielastic, deep-inelastic, and quasifission collision mechanisms are studied via analyzing the angular distributions of fragments and the energy dissipation processes during the collisions. The measured isotope production cross sections of projectile-like fragments are reasonably well reproduced by the calculation of the ImQMD model together with the GEMINI code. The isotope production cross sections for the target-like fragments and double differential cross sections of $^{199}$Pt, $^{203}$Pt, and $^{208}$Pt are calculated. It is shown that about 50 new neutron-rich heavy nuclei can be produced via deep-inelastic collision mechanism, where the production cross sections are from 10−3 to 10−6 mb. The corresponding emission angle and the kinetic energy for these new neutron-rich nuclei locate at 40∘–60∘ and 100–200 MeV, respectively.

High spin states in 170Ta have been studied via 159Tb(16O, 5nγ)170Ta reaction at 105 MeV beam energy. Three rotational bands have been observed among which one coupled band and an unfavored ΔI = 2 transition sequence of the semidecoupled band are identified in this work. The effects of the π½-[541] proton intruder orbital are qualitatively discussed.

A method to calculate the concentrations of accelerator-induced radionuclides in the accelerator hall is presented. Calculations of the short-term diffusion factors, the coordinates of the maximum concentration positions, and γ-submersion dose for short-life radionuclide 13 N, have been performed. The environment impact of radioactivity released by accelerators are discussed.

High-spin states of 119Xe have been investigated by in-beam γ-ray spectroscopy via the reaction of 16O bombarding a 106Cd target at beam energies of 67-80 MeV. No enhanced E1 transition was observed, the non-existence of octupole correlations in 119Xe.

Unknown β-delayed proton precursor 135Gd has been synthesized by the reaction 106Cd ( 32S, 3n ) and identified using a helium-jet recoil fast tape-transport system with a γ(X)-p coincidence measurements. Its β-delayed proton spectrum has been observed. The half-life of 135Gd decay has been determined to be 1.1 ± 0.2 s.