传统的传感器网络多目标定位方法面临的关键问题是目标与回波数据之间的匹配关联,而关联过程会带来计算量大以及如何准确提取目标的问题。基于成像策略的双站距离空间投影(Bistatic Range Space Projection,BRSP)定位算法可以有效地解...传统的传感器网络多目标定位方法面临的关键问题是目标与回波数据之间的匹配关联,而关联过程会带来计算量大以及如何准确提取目标的问题。基于成像策略的双站距离空间投影(Bistatic Range Space Projection,BRSP)定位算法可以有效地解决回波关联问题。然而,此算法存在运算量较大以及定位精度较低的问题。该文提出一种快速高精度双站距离空间投影(Fast and High Precision Bistatic Range Space Projection)定位算法。该算法采用分层处理,先进行低分辨率投影定位,获取目标可能区域,再以更高分辨率在目标可能区域进行投影定位,以减少运算量。然后将定位结果作为初值,构建方程组,利用泰勒级数展开算法进一步提高定位精度。仿真验证了该文所提方法的有效性,与BRSP定位算法相比,该文算法在提高定位精度的同时,相同硬件条件下定位速度可以提高数十倍,有利于实现实时定位。展开更多
Graphitic carbon nitride quantum dots(CNQDs) are emerging as attractive photoluminescent(PL)materials with excellent application potential in fluorescence imaging and heavy-metal ion detection. However, three limitati...Graphitic carbon nitride quantum dots(CNQDs) are emerging as attractive photoluminescent(PL)materials with excellent application potential in fluorescence imaging and heavy-metal ion detection. However, three limitations, namely, low quantum yields(QYs), self-quenching,and excitation-dependent PL emission behaviors, severely impede the commercial applications of crystalline CNQDs.Here we address these three challenges by synthesizing borondoped amorphous CNQDs via a hydrothermal process followed by the top±down cutting approach. Structural disorder endows the amorphous boron-doped CNQDs(B-CNQDs)with superior elastic strain performance over a wide range of pH values, thus effectively promoting mass transport and reducing exciton quenching. Boron as a dopant could fine-tune the electronic structure and emission properties of the PL material to achieve excitation-independent emission via the formation of uniform boron states. As a result, the amorphous B-CNQDs show unprecedented fluorescent stability(i.e., no obvious fading after two years) and a high QY of 87.4%;these values indicate that the quantum dots obtained are very promising fluorescent materials. Moreover, the B-CNQDs show bright-blue fluorescence under ultraviolet excitation when applied as ink on commercially available paper and are capable of the selective and sensitive detection of Fe^(2+) and Cd^(2+) in the parts-per-billion range. This work presents a novel avenue and scientific insights on amorphous carbon-based fluorescent materials for photoelectrical devices and sensors.展开更多
Hydrophobic fluorescence:Tan and his colleagues recently introduced a brand new chemotype of environment-sensitive fluorescent turn-on probes to detect the hydrophobic ligand-binding domain by using SBD fluorophore.Th...Hydrophobic fluorescence:Tan and his colleagues recently introduced a brand new chemotype of environment-sensitive fluorescent turn-on probes to detect the hydrophobic ligand-binding domain by using SBD fluorophore.The design strategy described in this report generalized the environment sensitivity turn-on mechanism to recognize a specific protein,which provides a robust breakthrough for interchanging fluorescence in conventional small-molecule fluorescent imaging.展开更多
文摘传统的传感器网络多目标定位方法面临的关键问题是目标与回波数据之间的匹配关联,而关联过程会带来计算量大以及如何准确提取目标的问题。基于成像策略的双站距离空间投影(Bistatic Range Space Projection,BRSP)定位算法可以有效地解决回波关联问题。然而,此算法存在运算量较大以及定位精度较低的问题。该文提出一种快速高精度双站距离空间投影(Fast and High Precision Bistatic Range Space Projection)定位算法。该算法采用分层处理,先进行低分辨率投影定位,获取目标可能区域,再以更高分辨率在目标可能区域进行投影定位,以减少运算量。然后将定位结果作为初值,构建方程组,利用泰勒级数展开算法进一步提高定位精度。仿真验证了该文所提方法的有效性,与BRSP定位算法相比,该文算法在提高定位精度的同时,相同硬件条件下定位速度可以提高数十倍,有利于实现实时定位。
基金supported by the National Natural Science Foundation of China (51772085 and 12072110)the Natural Science Foundation of Hunan Province (2020JJ4190)。
文摘Graphitic carbon nitride quantum dots(CNQDs) are emerging as attractive photoluminescent(PL)materials with excellent application potential in fluorescence imaging and heavy-metal ion detection. However, three limitations, namely, low quantum yields(QYs), self-quenching,and excitation-dependent PL emission behaviors, severely impede the commercial applications of crystalline CNQDs.Here we address these three challenges by synthesizing borondoped amorphous CNQDs via a hydrothermal process followed by the top±down cutting approach. Structural disorder endows the amorphous boron-doped CNQDs(B-CNQDs)with superior elastic strain performance over a wide range of pH values, thus effectively promoting mass transport and reducing exciton quenching. Boron as a dopant could fine-tune the electronic structure and emission properties of the PL material to achieve excitation-independent emission via the formation of uniform boron states. As a result, the amorphous B-CNQDs show unprecedented fluorescent stability(i.e., no obvious fading after two years) and a high QY of 87.4%;these values indicate that the quantum dots obtained are very promising fluorescent materials. Moreover, the B-CNQDs show bright-blue fluorescence under ultraviolet excitation when applied as ink on commercially available paper and are capable of the selective and sensitive detection of Fe^(2+) and Cd^(2+) in the parts-per-billion range. This work presents a novel avenue and scientific insights on amorphous carbon-based fluorescent materials for photoelectrical devices and sensors.
基金supported by the National Natural Science Foundation of China (81370085)the Program of New Century Excellent Talents in University (NCET-11-0306)+2 种基金the Fok Ying Tong Education Foundation (122036)the Shandong Natural Science Foundation (JQ201019)the Independent Innovation Foundation of Shandong University (2010JQ005 and 2012JC002).
文摘Hydrophobic fluorescence:Tan and his colleagues recently introduced a brand new chemotype of environment-sensitive fluorescent turn-on probes to detect the hydrophobic ligand-binding domain by using SBD fluorophore.The design strategy described in this report generalized the environment sensitivity turn-on mechanism to recognize a specific protein,which provides a robust breakthrough for interchanging fluorescence in conventional small-molecule fluorescent imaging.
