Acer pentaphyllum is a critically endangered maple confined to the valley of Yalong River in Southwest China. The whole chloroplast genome of A. pentaphyllum was 156,862 bp in length with a typical quadripartite structure, containing a large single-copy (LSC) region of 85,292 bp, a small single-copy (SSC) region of 18,146 bp, and a pair of inverted repeat (IR) regions of 26,712 bp separated among them. Totally 137 unique genes were predicted, comprising 89 protein-coding genes, 39 tRNA genes, and 8 rRNA genes (4 rRNA types). The phylogenetic analysis showed that A. pentaphyllum was resolved as sister to the clade containing A. griseum and A. sino-oblongum. This study reported the first complete chloroplast genome sequences of A. pentaphyllum and reconstructed a phylogeny tree based on 16 Sapindaceae species, which may provide new insight into phylogenetic studies of Sapindaceae and further conservation strategies for A. pentaphyllum.

Nuclear energy is an efficient energy source. Nuclear fuel has the advantages of high energy density and convenient transportation and storage. After decades of tortuous development, nuclear energy has been well utilized in many ways, especially in the field of nuclear power generation. However, as the number of nuclear power plants continues to increase, the problem of nuclear waste disposal is becoming more and more serious. Nuclear waste disposal is a complex process. For nuclear waste treatment, people initially only temporarily deposit these nuclear wastes or dump them directly. However, as people’s awareness of nuclear waste increases, and the huge potential threat of nuclear waste is known, it is necessary to analyze the current characteristics of nuclear waste and its pollution status in order to find a better nuclear waste treatment and management method.

Computational fluid dynamics numerical simulation method was used to numerically simulate the combustion process in 700 °C ultra-supercritical compact swirl opposed coal-fired boiler. The flow field distribution, composition distribution and NO distribution in the furnace were obtained through simulation. Simulating the NO generation in the boiler when the burner is put into different operation modes under different loads. The results show that the velocity and temperature fields in the ultra-supercritical compact boiler have the same characteristics as the typical swirl opposed coal-fired boiler. The O2 concentration showed good consistency with the main gas products CO and CO2 concentration. To a certain extent, NO generation and distribution characteristics are related with the temperature field. When the burner is put into operation in different ways, NO generation and distribution are different correspondingly. The simulation and test can provide theoretical basis for the technical implementation and structural optimization of the ultra-supercritical compact boiler at 700 °C.