[en] Dielectron pairs can be produced in nuclear reactions from many processes such as the proton-neutron bremsstrahlung, the delta decay, the annihilation of pion on nucleon, and the pion-pion annihilation. Based on the transport model. The authors calculate dielectron production from both proton-nucleus and nucleus-nucleus collisions. In this paper the possibility of studying the pion dispersion relation in dense nuclear matter via the dielectron invariant mass spectrum is discussed

[en] The crystallized cubic boron nitride (c-BN) films have been grown on silicon (100) wafer substrate successfully at room temperature by using a pulsed plasma enhanced chemical vapor deposition technique. Infrared absorption spectra and x-ray diffraction indicate that deposited boron nitride films mainly consist of c-BN phase. The scanning electron microscopy images exhibit regular grain shapes. The mean grain size is about 500 nm. The ratio of c-BN phase to h-BN phase in the deposited thin films mainly depends on the discharging voltages that producing the pulsed plasma

[en] Kaon production from meson-meson annihilation is enhanced significantly if the hadron masses are reduced in hot dense nuclear matter as a result of the restoration of chiral symmetry. In an expanding fireball model for heavy-ion collisions, the authors demonstrate that the observed enhancement of kaon yield in high energy heavy-ion collisions can be explained by this effect

[en] Dielectron pairs can be produced in nuclear reactions from many processes such as the proton-neutron bremsstrahlung, the delta decay, the annihilation of pions on nucleons, and the pion-pion annihilation. Based on the transport model, we calculate the dielectron-production cross section from nucleus-nucleus collisions and compare it to the available data. (orig.)

[en] Dielectron production in proton-nucleus reactions is studied in the cascade model. In addition to production from the proton-neutron bremsstrahlung and the decay of delta, we have also taken into account the contribution from the pion-nucleon interaction. The calculated dielectron invariant mass spectra are compared to the data obtained recently for proton-Be reactions at incident energies of 1.05, 2.1, and 4.9 GeV

[en] Kaon production from meson-meson annihilation is enhanced significantly because of the decrease of hadron masses in hot and dense matter as a result of the restoration of chiral symmetry. We show that this can lead to enhanced kaon yield in high-energy heavy-ion collisions

[en] In order to achieve steady state and high performance plasma in EAST, a new lower hybrid current drive system at a frequency of 4.6 GHz has been built. The system is composed of 24 continuous wave (CW) klystron amplifiers to generate 6MW/CW microwave, 24 standard rectangle waveguide transmission lines with water-cooling plate, a multi-junction grill composed of 576 active (in groups of 8) and 84 passive sub-waveguides arranged in 12 rows and 6 columns, and four sets of high voltage power supplies. The power value and the spectrum of the launched microwave from the antenna can be controlled by the low-power microwave circuits in front of the klystrons. The new LHCD system has been applied to the experiments on EAST tokmak since 2014, and the obtained results suggest that it is effective to couple the wave into plasma and drive plasma current.

[en] The effects of rare-earth element Er on the microstructure and mechanical properties of an as-extruded Al-Mg alloy have been studied. It has been shown that without solution treatment after thermomechanical process, the addition of Er obviously decreases the yield strength, tensile strength and elongation of the as-extruded Al-Mg alloy. Microstructural analysis indicates that coarse constituents with Er and Mg have been formed in the alloys containing Er, and thus reduce the solubility of Mg in the matrix. The reducement of solubility of Mg decreases the interaction between Mg solute atoms and dislocations, and thus degrades the yield strength of the alloy. During deformation, the constituents with Er and Mg fracture first and act as the microcrack sources due to the stress concentration. The results indicate that solution treatment after thermomechanical process is a fundamental procedure to improve the mechanical properties of the Al-Mg alloys by the addition of Er element

[en] In heavy-ion collisions, kaons can be produced from baryon-baryon, meson-baryon, and meson-meson interactions. Simple meson-exchange models are introduced to study kaon production from these processes in the free space. These models are then extended to determine kaon production in hot, dense nuclear matter by taking into account the decreasing hadron masses as a result of the restoration of chiral symmetry and the condensation of kaons. We find that the cross sections for kaon production from all three processes are enhanced. In particular, the effect of decreasing hadron masses on kaon production from the meson-meson annihilation is most significant. In the hydrochemical model for heavy-ion collisions, we demonstrate that the observed enhancement of kaon yield in high-energy heavy-ion collisions can be explained if the medium effect is included

[en] An improved terrestrial experiment to test the equivalence principle for rotating extended bodies is presented, and a new upper limit for the violation of the equivalence principle is obtained at the level of 1.6x10^-7, which is limited by the friction of the rotating gyroscope. This means that the spin-gravity interaction between the extended bodies has not been observed at this level