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91.
物联网终端安全接入认证是保证电力物联网大规模建设的关键性技术.传统认证方案通常采用的椭圆曲线密码算法,计算量大,不能抵抗量子攻击.数论研究单元算法可以抵抗量子攻击,与椭圆曲线密码采用点乘算法相比,计算速度快.因此提出了一种时间变换数论研究单元算法物联网动态安全接入认证算法,使用动态变化时间序列通过哈希函数产生动态密钥,... 相似文献
92.
Jiao Shi Weihua Yu Chunwei Hu Haiyan Duan Jiaxing Ji Yuanyuan Kang Kun Cai 《International journal of molecular sciences》2022,23(12)
The path of crack propagation in a graphene sheet is significant for graphene patterning via the tearing approach. In this study, we evaluate the fracture properties of pre-cracked graphene during the tearing process, with consideration of the effects of the aspect ratio, loading speed, loading direction, and ambient temperatures on the crack propagation in the monolayer sheet. Some remarkable conclusions are drawn based on the molecular dynamic simulation results, i.e., a higher loading speed may result in a complicated path of crack propagation, and the propagation of an armchair crack may be accompanied by sp carbon links at high temperatures. The reason for this is that the stronger thermal vibration reduces the load stress difference near the crack tip and, therefore, the crack tip can pass through the sp link. A crack propagates more easily along the zigzag direction than along the armchair direction. The out-of-plane tearing is more suitable than the in-plane tearing for graphene patterning. The path of crack propagation can be adjusted by changing the loading direction, e.g., a rectangular graphene ribbon can be produced by oblique tearing. This new understanding will benefit the application of graphene patterning via the tearing approach. 相似文献
93.
Ze-Lin Cai Zi-Lin Peng Meng-Qi Wang Jia-Yan Wu Hao-Sen Fan Yu-Fei Zhang 《稀有金属(英文版)》2021,(6):1451-1458
Layered nickel oxides have been focused with intense research interests as high-performance lithium-ion batterie(LIB) anode.However,it is hard to obtain few layered nickel oxides material directly as it easily forms bulk material with the strong interaction between the interlayer.In this work,two-dimensional(2 D) nickel-based coordination polymers were successfully prepared according to aqueous phase copolymerization approach.And then uniform carbondoped NiO nanosheets were successfully obtained from facile solution assembly and post-thermal treatment.The detailed electrochemical testing shows that the uniform NiO nanocrystals encapsulated into porous N-doped carbon(NiO@NC) nanosheets present much higher rate capability with the discharge specific capacity of 782.7 mAh·g~(-1) at high current density of 2.0 A·g~(-1) than pure NiO(690 mAh·g~(-1)).It also shows long-term cycling performance with 91 % retention after 50 cycles at 1.0 A·g~(-1).The high rate capability,cycling stability and the easy synthesis make NiO@NC nanosheets as a promising candidate for LIB anode and build up new way for the fabrication of metal oxides anode materials. 相似文献
94.
Yi Ren Xian-bo Shi Zhen-guo Yang Yi-yin Shan Wei Ye Gui-xi Cai Ke Yang 《钢铁研究学报(英文版)》2021,28(6):752-761
The effect of microstructures on strength, strain capacity and low temperature toughness of a micro-alloyed pipeline steel was elucidated. Five various dual-pha... 相似文献
95.
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97.
Shengchen Gu Xupeng Zang Lei Jiang Ting Gu Fanming Meng Sixiu Huang Gengyuan Cai Zicong Li Zhenfang Wu Linjun Hong 《International journal of molecular sciences》2022,23(15)
Litter size is an important indicator to measure the production capacity of commercial pigs. Spontaneous embryo loss is an essential factor in determining sow litter size. In early pregnancy, spontaneous embryo loss in porcine is as high as 20–30% during embryo implantation. However, the specific molecular mechanism underlying spontaneous embryo loss at the end of embryo implantation remains unknown. Therefore, we comprehensively used small RNA sequencing technology, bioinformatics analysis, and molecular experiments to determine the microRNA (miRNA) expression profile in the healthy and arresting embryo implantation site of porcine endometrium on day of gestation (DG) 28. A total of 464 miRNAs were identified in arresting endometrium (AE) and healthy endometrium (HE), and 139 differentially expressed miRNAs (DEMs) were screened. We combined the mRNA sequencing dataset from the SRA database to predict the target genes of these miRNAs. A quantitative real-time PCR assay identified the expression levels of miRNAs and mRNAs. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were performed on differentially expressed target genes of DEMs, mainly enriched in epithelial development and amino acids metabolism-related pathways. We performed fluorescence in situ hybridization (FISH) and the dual-luciferase report gene assay to confirm miRNA and predicted target gene binding. miR-205 may inhibit its expression by combining 3′-untranslated regions (3′ UTR) of tubulointerstitial nephritis antigen-like 1 (TINAGL1). The resulting inhibition of angiogenesis in the maternal endometrium ultimately leads to the formation of arresting embryos during the implantation period. This study provides a reference for the effect of miRNA on the successful implantation of pig embryos in early gestation. 相似文献
98.
99.
Zahirul I. Talukder William Underwood Christopher G. Misar Gerald J. Seiler Xiwen Cai Xuehui Li Lili Qi 《International journal of molecular sciences》2022,23(14)
Sclerotinia head rot (HR), caused by Sclerotinia sclerotiorum, is an economically important disease of sunflower with known detrimental effects on yield and quality in humid climates worldwide. The objective of this study was to gain insight into the genetic architecture of HR resistance from a sunflower line HR21 harboring HR resistance introgressed from the wild perennial Helianthus maximiliani. An F2 population derived from the cross of HA 234 (susceptible-line)/HR21 (resistant-line) was evaluated for HR resistance at two locations during 2019–2020. Highly significant genetic variations (p < 0.001) were observed for HR disease incidence (DI) and disease severity (DS) in both individual and combined analyses. Broad sense heritability (H2) estimates across environments for DI and DS were 0.51 and 0.62, respectively. A high-density genetic map of 1420.287 cM was constructed with 6315 SNP/InDel markers developed using genotype-by-sequencing technology. A total of 16 genomic regions on eight sunflower chromosomes, 1, 2, 10, 12, 13, 14, 16 and 17 were associated with HR resistance, each explaining between 3.97 to 16.67% of the phenotypic variance for HR resistance. Eleven of these QTL had resistance alleles from the HR21 parent. Molecular markers flanking the QTL will facilitate marker-assisted selection breeding for HR resistance in sunflower. 相似文献
100.
The spatiotemporal evolution of hairpin vortex structures in a fully developed turbulent boundary layer is investigated qualitatively and quantitatively by usin... 相似文献