By irradiating the nuclear material SiC, the characteristics of continuous wide energy spectrum, short pulse and high instantaneous current intensity of the laser-accelerated proton beam have been characterized. The SiC samples were placed at a distance of 4 cm from the target. The 300 shots proton beams were irradiated with a continuous wide energy spectrum proton beam of 1–4.5 MeV, which satisfied the exponential energy spectrum distribution. The surface and cross-section Raman characterizations showed that the intensity of the SiC scattering peaks after irradiation were reduced. The overall trend of Raman cross-section measurement was consistent with the depth of the distribution of energy loss by SRIM simulation. Thus, the experimental characterization of laseraccelerated proton beam with continuous energy distribution was realized. In addition, experiments showed that the short pulse characteristic of the laser-accelerated proton beam could produce a relatively high instantaneous beam current density on the SiC surface. The ultra-fast wide energy spectrum irradiation provides a possibility in simulated reactor neutron irradiation.

Using MCD19A2, a new product of MODIS with high temporal and spatial resolution(daily; 1 km × 1 km), spatial-temporal distribution of aerosol optical depth (AOD) over northeastern China during 2000?2019 were studied and analyzed. The results showed that the average AOD of the northeastern China in recent 20 years is 0.23, and have changed little. 2003 is the year with the highest AOD (0.38), which is mainly affected by spring drought, sand blowing, straw burning and other factors. In terms of spatial distribution, there is a decreasing trend from south to north. Liaoning province is higher than Jilin province and Jilin province is higher than Heilongjiang Province. AOD high-value areas are concentrated in the urban agglomeration of south-central region of Liaoning Province and other areas with dense population and developed industry. Low-value area is distributed in the greater Hinggan Mountains, lesser Hinggan Mountains, Changbai Mountains and other mountainous areas. Seasonal distribution of AOD; Higher in spring and summer, lower in autumn and winter. The results can be used to study the effects of aerosols on the atmospheric radiation balance or to simulate the concentration of particulate matter.

Two new methods for improving Chinese spelling correction are proposed. The first one is to add Gaussian Bias matrices to the Transformer’s attention mechanism, which is used to improve the model’s attention to local text and to extract information from the wrong words and the surrounding text in the error text. Secondly, the ON_LSTM model is used to extract grammatical information on the special grammatical structure features exhibited by the error text. The experimental results show that both methods are effective in improving accuracy and recall, and the model after fusing the two methods achieves the highest F1 value.