Two-dimensional(2D)atomically thin quantum dots(QDs)possess extraordinary electrical and optical properties.However,fabricating high quality 2D QDs via a universal and reliable technique remains a challenge.Here,we re...Two-dimensional(2D)atomically thin quantum dots(QDs)possess extraordinary electrical and optical properties.However,fabricating high quality 2D QDs via a universal and reliable technique remains a challenge.Here,we report a simple strategy to prepare high quality,monolayer single crystal 2D QDs via ultrathin cutting 2D bulk single crystals by ultramicrotome,followed by an exfoliation process.The as-prepared 2D QDs have pristine surface,high quality,high monolayer yield and high photoluminescence quantum yield(the highest photoluminescence quantum yield of WS2 is18%),which can be used as promising,low toxic,biocompatible,and good cell-permeability fluorescent labeling agents for in vitro imaging.展开更多
In this paper,we present a central cutting plane algorithm for solving convex min-max semi-infinite programming problems.Because the objective function here is non-differentiable,we apply a smoothing technique to the ...In this paper,we present a central cutting plane algorithm for solving convex min-max semi-infinite programming problems.Because the objective function here is non-differentiable,we apply a smoothing technique to the considered problem and develop an algorithm based on the entropy function.It is shown that the global convergence of the proposed algorithm can be obtained under weaker conditions.Some numerical results are presented to show the potential of the proposed algorithm.展开更多
基金This work was supported by the National Natural Science Foundation of China(21573253)the National Key Research and Developmet Program of China(2017YFA0204700)the Strategic Priority Research Programme of the Chinese Academy of Sciences(XDB12010000).
文摘Two-dimensional(2D)atomically thin quantum dots(QDs)possess extraordinary electrical and optical properties.However,fabricating high quality 2D QDs via a universal and reliable technique remains a challenge.Here,we report a simple strategy to prepare high quality,monolayer single crystal 2D QDs via ultrathin cutting 2D bulk single crystals by ultramicrotome,followed by an exfoliation process.The as-prepared 2D QDs have pristine surface,high quality,high monolayer yield and high photoluminescence quantum yield(the highest photoluminescence quantum yield of WS2 is18%),which can be used as promising,low toxic,biocompatible,and good cell-permeability fluorescent labeling agents for in vitro imaging.
基金supported by National Natural Science Foundation of China(Grant No.11271221)
文摘In this paper,we present a central cutting plane algorithm for solving convex min-max semi-infinite programming problems.Because the objective function here is non-differentiable,we apply a smoothing technique to the considered problem and develop an algorithm based on the entropy function.It is shown that the global convergence of the proposed algorithm can be obtained under weaker conditions.Some numerical results are presented to show the potential of the proposed algorithm.
