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High strength and high toughness are important indicators of material load-bearing capacity and reliability. The challenge remains on how to improve the material strength while maintaining its toughness during conventional surface treatments, such as overall hardening. This paper proposed a multi-pass discrete laser spot hardening (DLSH) process based on time-domain energy modulation. The characteristics of 42CrMoV alloy steel treated with multi-pass DLSH process, compared with conventional DLSH process, were investigated in terms of surface quality, microstructure evolution, and tensile properties. The results demonstrated that the surface quality of the hardened point lattice using multi-pass processing was significantly improved, and the microstructure was refined after multiple rapid austenitization cycles. Additionally, different “soft-hard” distribution states were formed on the sample surface. The ultimate tensile strength of the samples treated with conventional DLSH and multi-pass DLSH processes was increased by 9.5% and 5.2% respectively. However, the latter exhibited significantly higher elongation at fracture and showed a ductile fracture, while the former displayed brittle fracture. The multi-pass DLSH process maintained the original material toughness while enhancing its strength. Therefore, the multi-pass DLSH process holds significant importance in improving surface quality and material toughness in laser hardening applications.

Sugarcane, a major sugar and energy crop worldwide faces an increasing demand for higher yields. Identifying yield-related markers and candidate genes is valuable for breeding high-yield varieties using molecular techniques. In this work, seven yield-related traits were evaluated in a diversity panel of 159 genotypes, derived from Tripidium arundinaceum, Saccharum spontaneum, and modern sugarcane genotypes. All traits exhibited significant genetic variance with high heritability and high correlations. Genetic diversity analysis reveals a genomic decay of 23 kb and an average single nucleotide polymorphism (SNP) number of 25,429 per genotype. These 159 genotypes were divided into 4 subgroups. Genome-wide association analysis identified 47 SNPs associated with brix, spanning 36 quantitative trait loci (QTLs), and 138 SNPs for other traits across 104 QTLs, covering all 32 chromosomes. Interestingly, 12 stable QTLs associated with yield-related traits were identified, which contained 35 candidate genes. This work provides markers and candidate genes for marker-assisted breeding to improve sugarcane yields.

Metal surface laser micro-melting technology is widely used in laser cladding, laser welding and laser texture fields. In this paper, laser micro-melting model is established according to the surface morphology forming mechanism. The effects of boundary heat transfer, recoil pressure, surface tension, capillary force and thermal capillary force on micro-flow are fully considered in this model. The study found that the recoil pressure and capillary force are the main reason for the height variation of the morphology bulge. In the heating stage, the capillary force and thermal capillary force dominate the flow of molten metal, while in the cooling stage, the capillary force dominates the flow of the metal, and the capillary force gradually converges from both sides to the middle. This is also the reason why the morphology almost does not change in the radial direction but continues to change in the axial bulge height during cooling stage.

A two-dimensional analytical model based on the Reynolds equation considering mass conservation cavitation is proposed to investigate the performance of partially textured thrust bearings with circular grooves. The geometrical and distribution parameters of the circular grooves are numerically optimized to obtain the maximum load-carrying capacity. The samples of partially textured thrust bearings are machined by the picosecond laser, and tribological experiments are carried out on an MMW-1 tribological rig. The average friction coefficient and the friction reduction ratio are applied to analyze the tribological performance of partially textured thrust bearings. Through a comparative analysis, the optimal geometrical values obtained from the experimental results are in good agreement with the theoretical analysis, especially at high rotation speeds and a low load condition.

Lithium–sulfur (Li–S) batteries with high specific energy density, low cost, and environmental friendliness of sulfur have been regarded as a competitive alternative to replace lithium-ion batteries. However, the shuttle effect and the sluggish conversion rate of lithium polysulfides (LiPSs) have seriously limited the practical application of Li–S batteries. Herein, high-entropy oxides grown on the carbon cloth (CC/HEO) are synthesized by a simple and ultrafast solution combustion method for the sulfur cathode. The as-prepared composites possess abundant HEO active sites for strong interaction with LiPSs, which can significantly promote redox kinetics. Besides, the carbon fiber substrate not only ensures high electrical conductivity but also accommodates large volume change, leading to a stable sulfur electrochemistry. Benefiting from the rational design, the Li–S batteries with CC/HEO as cathode skeleton exhibits good cyclability with a capacity decay rate of 0.057% per cycle after 1000 cycles at 2 C. More importantly, the Li–S batteries with 4.3 mg cm–2high sulfur loading can still retain a high capacity retention of 78.2% after 100 cycles.

Driven by the strong adsorptive and catalytic ability of metal sulfides for soluble polysulfides, it is considered as a potential mediator to resolve the problems of shuttle effect and slow reaction kinetics of polysulfides in lithium−sulfur (Li−S) batteries. However, their further development is limited by poor electrical conductivity and bad long-term durability. Herein, one type of new catalyst composed of SnS/SnS2heterostructures on hierarchical porous carbon (denoted as SnS/SnS2–HPC) by a simple hydrothermal method is reported and used as an interlayer coating on the conventional separator for blocking polysulfides. The SnS/SnS2–HPC integrates the advantages of a porous conductive network for promoting the transport of electrons and an enhanced electrocatalyst for accelerating polysulfides conversion. As a result, such a cell coupled with a SnS/SnS2–HPC interlayer exhibits a long-term lifespan of 1200 cycles. This work provides a new cell configuration by using heterostructures with a built-in electric field formed from a p-n heterojunction to improve the performance of Li–S batteries.

•Investigating how living built environments affect residents’ mobility at an aggregated level.•Movement distance, activity space, and the number of stops were derived from raw mobile phone data to characterize human mobility.•The living built environment could better explain the activity space than the movement distance and number of stops.

Modern sugarcanes are polyploid interspecific hybrids, combining high sugar content from Saccharum officinarumwith hardiness, disease resistance and ratooning of Saccharum spontaneum. Sequencing of a haploid S. spontaneum, AP85-441, facilitated the assembly of 32 pseudo-chromosomes comprising 8 homologous groups of 4 members each, bearing 35,525 genes with alleles defined. The reduction of basic chromosome number from 10 to 8 in S. spontaneumwas caused by fissions of 2 ancestral chromosomes followed by translocations to 4 chromosomes. Surprisingly, 80% of nucleotide binding site-encoding genes associated with disease resistance are located in 4 rearranged chromosomes and 51% of those in rearranged regions. Resequencing of 64 S. spontaneumgenomes identified balancing selection in rearranged regions, maintaining their diversity. Introgressed S. spontaneumchromosomes in modern sugarcanes are randomly distributed in AP85-441 genome, indicating random recombination among homologs in different S. spontaneumaccessions. The allele-defined Saccharumgenome offers new knowledge and resources to accelerate sugarcane improvement.

Peanut (Arachis hypogaeaL.) nodulation is relatively diverged from other legumes. Further understanding of nodulation mechanisms would facilitate improvement of biological N fixation and yield in peanut. The objective of this study was to characterize the non‐nodulating (Nod−) peanut recombinant inbred lines (RILs) in comparison to their nodulating (Nod+) sister RILs morphologically and genetically. Two pairs of Nod− and Nod+ RILs were inoculated with rhizobia for morphological observation. Nodules and root hairs were absent in Nod− lines and present in Nod+ lines. The Nod− lines had a much smaller canopy with yellow leaves and fewer pods than Nod+ lines. Simple‐sequence repeat (SSR) marker genotyping of the two pairs of RILs and their parental lines revealed several chromosome regions differing between Nod− and Nod+ sister lines, which potentially harbor the genes controlling nodulation. Two F2populations segregating for nodulation were constructed by crossing the two Nod− lines with their Nod+ sister lines. The segregation ratios of Nod−/Nod+ of the two populations followed 7:9 and 7:57, respectively, indicating that multiple genes were involved in controlling peanut nodulation. The results from this study provided important morphological and genetic information related to peanut nodulation, which paved the road for further mapping and cloning of peanut nodulation genes and for eventually developing peanut cultivars with improved N fixation efficiency.

In the version of this article originally published, the accession codes listed in the data availability section were incorrect and the section was incomplete. The text for this section should have read “The genome assembly and gene annotation have been deposited in the NCBI database under accession number QVOL00000000, BioProject number PRJNA483885 and BioSample number SAMN09753102. The data can also be downloaded from the following link: http://www.life.illinois.edu/ming/downloads/Spontaneum_genome/.” The errors have been corrected in the HTML and PDF versions of the article.