The High Energy X-ray telescope (HE) on-board the Hard X-ray Modulation Telescope (Insight-HXMT) can serve as a wide Field of View (FOV) gamma-ray monitor with high time resolution (μs) and large effective area (up to thousands cm2). We developed a pipeline to search for Gamma-Ray Bursts (GRBs), using the traditional signal-to-noise ratio (SNR) method for blind search and the coherent search method for targeted search. By taking into account the location and spectrum of the burst and the detector response, the targeted coherent search is more powerful to unveil weak and sub-threshold bursts, especially those in temporal coincidence with Gravitational Wave (GW) events. Based on the original method in literature, we further improved the coherent search to filter out false triggers caused by spikes in light curves, which are commonly seen in gamma-ray instruments (e.g. Fermi/GBM, POLAR). We show that our improved targeted coherent search method could eliminate almost all false triggers caused by spikes. Based on the first two years of Insight-HXMT/HE data, our targeted search recovered 40 GRBs, which were detected by either Swift/BAT or Fermi/GBM but too weak to be found in our blind search. With this coherent search pipeline, the GRB detection sensitivity of Insight-HXMT/HE is increased to about 1.5E-08 erg cm−2 (200 keV–3 MeV). We also used this targeted coherent method to search Insight-HXMT/HE data for electromagnetic (EM) counterparts of LIGO-Virgo GW events (including O2 and O3a runs). However, we did not find any significant burst associated with GW events.

Ionizing radiation produces reactive oxygen species (ROS), which cause damage to cells. We have synthesized a class of ROS scavengers and found that one of them, named GANRA-5, exhibits high radio-protective effects against both heavy ion irradiation and X-rays, while at the same time displaying low levels of toxicity. Pre-administration with an effective dose of GANRA-5 reduces radiation-induced damage to tissues and increases the survival rate of exposed mice. In this study, we evaluated the changes to the immune system via X-ray irradiation, and investigated how pre-administration of GANRA-5 exhibited preventative characteristics. Compared to the irradiated control groups, GANRA-5 treatment significantly reduced the radiation-induced spleen shrinkage and pathological changes. Moreover, pretreatment with GANRA-5 significantly (p < 0.01) enhanced the cellular immune response, which was characterized by higher peritoneal macrophage as well as splenocyte survival, and a higher ratio of CD4(+)/CD8(+) T lymphocytes. In addition, GANRA-5 treatment before whole body irradiation significantly improved the humoral response (p < 0.01) as indicated by the higher antibody titers of IgG, IgA, and IgM. Furthermore, GANRA-5 treatment significantly (p < 0.01) countered radiation-induced decreases in the titers of serum IL-2 and IL-4 when compared to irradiated but untreated control groups. In summary, these findings indicate that GANRA-5 provides effective protection to the immune system against X-ray-induced immunosuppression.

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Dy films, deposited on the surface of sintered Nd-Fe-B magnets by magnetron sputtering, were employed for grain boundary diffusion source. High coercivity sintered Nd-Fe-B magnets were successfully prepared. Effects of sputtering power and grain boundary diffusion processes (GBDP) on the microstructure and magnetic properties were investigated in detail. The dense and uniform Dy films were beneficial to prepare high coercivity magnets by GBDP. The maximum coercivity value of 1189 kA m −1 could be shown, which was an amplification of 22.3%, compared with that of as-prepared Nd-Fe-B magnet. Furthermore, the improved remanence and maximum energy product were also achieved through tuning grain boundary diffusion processes. Our results demonstrated that the formation of (Nd, Dy) 2 Fe 14 B shell surrounding Nd 2 Fe 14 B grains and fine, uniform and continuous intergranular RE-rich phases jointly contribute to the improved coercivity.