Large-area and high-quality two-dimensional crystals are the basis for the development of the next-generation electronic and optical devices.The synthesis of two-dimensional materials in wafer scales is the first crit...Large-area and high-quality two-dimensional crystals are the basis for the development of the next-generation electronic and optical devices.The synthesis of two-dimensional materials in wafer scales is the first critical step for future technology uptake by the industries;however,currently presented as a significant challenge.Substantial efforts have been devoted to producing atomically thin two-dimensional materials with large lateral dimensions,controllable and uniform thicknesses,large crystal domains and minimum defects.In this review,recent advances in synthetic routes to obtain high-quality two-dimensional crystals with lateral sizes exceeding a hundred micrometres are outlined.Applications of the achieved large-area two-dimensional crystals in electronics and optoelectronics are summarised,and advantages and disadvantages of each approach considering ease of the synthesis,defects,grain sizes and uniformity are discussed.展开更多
Defect-rich,highly porous two-dimensional carbon nanosheets(CNS) have attracted tremendous research interests in catalysis and environmental purification and other fields,because of their unique micromorphology,chemic...Defect-rich,highly porous two-dimensional carbon nanosheets(CNS) have attracted tremendous research interests in catalysis and environmental purification and other fields,because of their unique micromorphology,chemical stability and high specific surface area.Herein,in this work,we report a new solution to synthesize an ultrathin two-dimensional CNS with rich defects and abundant pores via two-step etching the Ti_(3)AlC_(2)with the help of I2and NaOH.The CNS thickness,specific surface area and pore volume could be all tunable by adding the amount of I2.And the highest specific surface area and pore volume of the synthesized 2D CNS can be achieved 1134.4 m^(2)/g and 0.80 cm^(3)/g,with a thickness of only 0.64 nm and a yield of 35.9%.When employed as the anodes for lithium-ion batteries,the synthesized CNS anodes exhibit good cycling and rate capabilities.This work provides a novel and facile strategy for synthesizing highly porous and defective 2D carbon materials with good lithium storage properties.展开更多
The two-dimensional cellular detonation propagating in a channel with area-changing cross section was numerically simulated with the dispersion-controlled dissipative scheme and a detailed chemical reaction model. Eff...The two-dimensional cellular detonation propagating in a channel with area-changing cross section was numerically simulated with the dispersion-controlled dissipative scheme and a detailed chemical reaction model. Effects of the flow ex-pansion and compression on the cellular detonation cell were investigated to illus-trate the mechanism of the transverse wave development and the cellular detona-tion cell evolution. By examining gas composition variations behind the leading shock,the chemical reaction rate,the reaction zone length,and thermodynamic parameters,two kinds of the abnormal detonation waves were identified. To explore their development mechanism,chemical reactions,reflected shocks and rarefac-tion waves were discussed,which interact with each other and affect the cellular detonation in different ways.展开更多
为了给电力通信网的安全管理提供有效工具,针对区域位置坐标难以定位与区域面积误差较大的问题,在二维云模型下提出一种电力通信网安全脆弱性区域检测方法。根据电力通信网络的连接方式以及工作原理,构建二维云模型,采集并处理电力通信...为了给电力通信网的安全管理提供有效工具,针对区域位置坐标难以定位与区域面积误差较大的问题,在二维云模型下提出一种电力通信网安全脆弱性区域检测方法。根据电力通信网络的连接方式以及工作原理,构建二维云模型,采集并处理电力通信网络数据,从网络节点、链路等方面评估电力通信网的综合安全脆弱性,通过与阈值的比对,得出脆弱性区域面积以及位置的检测结果。仿真实验结果表明,脆弱节点判断与预先设置情况基本一致,优化的设计方法检测出的脆弱性区域位置坐标与区域面积误差分别为1.6 m和1.82 m 2,均低于预设值,说明该方法具有良好的检测性能。展开更多
基金the financial support from“National Natural Science Foundation of China”(No.51850410506)。
文摘Large-area and high-quality two-dimensional crystals are the basis for the development of the next-generation electronic and optical devices.The synthesis of two-dimensional materials in wafer scales is the first critical step for future technology uptake by the industries;however,currently presented as a significant challenge.Substantial efforts have been devoted to producing atomically thin two-dimensional materials with large lateral dimensions,controllable and uniform thicknesses,large crystal domains and minimum defects.In this review,recent advances in synthetic routes to obtain high-quality two-dimensional crystals with lateral sizes exceeding a hundred micrometres are outlined.Applications of the achieved large-area two-dimensional crystals in electronics and optoelectronics are summarised,and advantages and disadvantages of each approach considering ease of the synthesis,defects,grain sizes and uniformity are discussed.
基金financially supported by the National Natural Science Foundation of China (No. 51902036)Natural Science Foundation of Chongqing Science & Technology Commission (No. cstc2019jcyj-msxm1407)+4 种基金Natural Science Foundation of Jiangsu Province (No. BK20200047)Natural Science Foundation of Chongqing Technology and Business University (No. 1952009)the Science and Technology Research Program of Chongqing Education Commission (Nos. KJQN201900826 and KJQN201800808)the Venture & Innovation Support Program for Chongqing Overseas Returnees (Nos. CX2021046 and CX2018129)the Innovation Group of New Technologies for Industrial Pollution Control of Chongqing Education Commission (No. CXQT19023)。
文摘Defect-rich,highly porous two-dimensional carbon nanosheets(CNS) have attracted tremendous research interests in catalysis and environmental purification and other fields,because of their unique micromorphology,chemical stability and high specific surface area.Herein,in this work,we report a new solution to synthesize an ultrathin two-dimensional CNS with rich defects and abundant pores via two-step etching the Ti_(3)AlC_(2)with the help of I2and NaOH.The CNS thickness,specific surface area and pore volume could be all tunable by adding the amount of I2.And the highest specific surface area and pore volume of the synthesized 2D CNS can be achieved 1134.4 m^(2)/g and 0.80 cm^(3)/g,with a thickness of only 0.64 nm and a yield of 35.9%.When employed as the anodes for lithium-ion batteries,the synthesized CNS anodes exhibit good cycling and rate capabilities.This work provides a novel and facile strategy for synthesizing highly porous and defective 2D carbon materials with good lithium storage properties.
文摘The two-dimensional cellular detonation propagating in a channel with area-changing cross section was numerically simulated with the dispersion-controlled dissipative scheme and a detailed chemical reaction model. Effects of the flow ex-pansion and compression on the cellular detonation cell were investigated to illus-trate the mechanism of the transverse wave development and the cellular detona-tion cell evolution. By examining gas composition variations behind the leading shock,the chemical reaction rate,the reaction zone length,and thermodynamic parameters,two kinds of the abnormal detonation waves were identified. To explore their development mechanism,chemical reactions,reflected shocks and rarefac-tion waves were discussed,which interact with each other and affect the cellular detonation in different ways.
文摘为了给电力通信网的安全管理提供有效工具,针对区域位置坐标难以定位与区域面积误差较大的问题,在二维云模型下提出一种电力通信网安全脆弱性区域检测方法。根据电力通信网络的连接方式以及工作原理,构建二维云模型,采集并处理电力通信网络数据,从网络节点、链路等方面评估电力通信网的综合安全脆弱性,通过与阈值的比对,得出脆弱性区域面积以及位置的检测结果。仿真实验结果表明,脆弱节点判断与预先设置情况基本一致,优化的设计方法检测出的脆弱性区域位置坐标与区域面积误差分别为1.6 m和1.82 m 2,均低于预设值,说明该方法具有良好的检测性能。
基金financially supported by the National Key R&D Program of China (2022YFA1503400)the National Natural Science Foundation of China (21991091)+2 种基金the Key Projects of Shandong Key R&D plan (2019JZZY010506)Taishan Scholar Foundation (tspd20210308)the Petro China Research and Development Projects (2020A-1816 and 2020A-1817)。