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Tracing of dye molecules in living plants through NaGdF_4:Yb^(3+),Er^(3+)fluorescent nanoprobes

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Journal of Rare Earths 2019年第3期37卷 237-241页

作者： Xiaofeng Wu Ya'nan Zhang Shiping Zhan Jin Li Guozheng Nie shigang hu Cong Yan Shaobing Wu Shengbin Cheng Junshan hu Lichun Shi Yunxin Liu School of Information and Electrical Engineering Hunan University of Science and Technology College of Physics and Electronics Science Hunan University of Science and Technology Key Laboratory of Organic Polymer Photoelectric Materials School of Science Xijing University

In this paper, we demonstrated trace of dye molecules in living plants. The NaGdF4:Yb^(3+),Er^(3+) nanoparticles probe was used to detect the rhodamine B(RhB) in bean sprout. It is found that the fluorescencedye can be efficiently imbibed during the growing process and the absorbance presented a position dependence effect, which was supported by the upconversion spectra and the fluorescent image characterization. In addition, the concentration of the residual RhB in bean sprout can be efficiently traced by the synthesized probe based on the fluorescent resonant energy transfer. Finally, the relation between the excitation power, concentration and the ratio of yellow to green emission are discussed in detail. These results can be helpful in understanding the RhB dye molecules absorbance process in vegetable growth and provide an efficient way to trace the residual dyes in vivo plant.

关键词： Rare-earth-doped materials Biological sensing and sensors Fluorescence Luminescence Upconversion nanoprobes

Improving error-correcting capability in DNA digital storage via soft-decision decoding

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National Science Review 2024年第2期11卷 135-144页

作者：丁璐璐伍世刚候志浩李阿伦许亚苹冯虎潘玮华阮珏 Shenzhen Branch Guangdong Laboratory of Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of Agriculture and Rural AffairsAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural Sciences Guangdong Provincial Key Laboratory of Plant Molecular Breeding State Key Laboratory for Conservation and Utilization of Subtropical Agro-BioresourcesSouth China Agricultural University

Error-correcting codes(ECCs) employed in the state-of-the-art DNA digital storage(DDS) systems suffer from a trade-off between error-correcting capability and the proportion of redundancy. To address this issue, in this study, we introduce soft-decision decoding approach into DDS by proposing a DNA-specific error prediction model and a series of novel strategies. We demonstrate the effectiveness of our approach through a proof-of-concept DDS system based on Reed-Solomon(RS) code, named as Derrick. Derrick shows significant improvement in error-correcting capability without involving additional redundancy in both in vitro and in silico experiments, using various sequencing technologies such as Illumina, Pac Bio and Oxford Nanopore Technology(ONT). Notably, in vitro experiments using ONT sequencing at a depth of 7× reveal that Derrick, compared with the traditional hard-decision decoding strategy, doubles the error-correcting capability of RS code, decreases the proportion of matrices with decoding-failure by 229-fold, and amplifies the potential maximum storage volume by impressive 32 388-fold. Also, Derrick surpasses ‘state-of-the-art' DDS systems by comprehensively considering the information density and the minimum sequencing depth required for complete information recovery. Crucially, the soft-decision decoding strategy and key steps of Derrick are generalizable to other ECCs' decoding algorithms.

关键词： DNA digital storage (DDS) error-correcting code (ECC) soft-decision decoding error-correcting capability storage volume

单边带光载LDPC-OFDM系统的传输性能

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中南大学学报（自然科学版） 2013年第3期44卷 1070-1075页

作者：席在芳刘懿吴笑峰胡仕刚湖南科技大学信息与电气工程学院湖南湘潭411201

对LDPC-OFDM信号在单边带光调制系统中的传输性能进行研究,介绍OFDM单边带调制系统原理,建立FDM单边带调制系统的仿真系统,仿真、分析并比较原始OFDM信号和LDPC-OFDM信号在单边带调制系统中的误码性能和星座图。研究结果表明:在传输距... 详细信息

对LDPC-OFDM信号在单边带光调制系统中的传输性能进行研究,介绍OFDM单边带调制系统原理,建立FDM单边带调制系统的仿真系统,仿真、分析并比较原始OFDM信号和LDPC-OFDM信号在单边带调制系统中的误码性能和星座图。研究结果表明:在传输距离相同的条件下,LDPC-OFDM信号的误码性能比原始OFDM信号的误码性能好;LDPC编码具有较强的纠错能力,前向纠错编码技术的使用弥补了光纤链路中色散对传输信号质量的影响;在OFDM信号的基础上采用LDPC编码能获得较好的编码性能增益。

关键词：单边带调制 OFDM信号 LDPC信号

Upconversion NaGdF4 nanoparticles for monitoring heat treatment and acid corrosion processes of hair

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Journal of Rare Earths 2016年第5期34卷 475-482页

作者：刘云新陈增辉吴笑峰胡仕刚胡盼余意戴港涛颜焕元唐志军 Department of Physics and Electrical Science Hunan University of Science and Technologp Xiangtan 411201 China INPAC-Institute for Nanoscale Physics and Chemsitry KU LeuvenCelestijnenlaan 200D B-3001Belgium School of Information and Electrical Engineering Hunan University of Science and TechnologyXiangtan 411201China College of Mechanical and Electrical Engineering Hunan University of Science and TechnologyXiangtan 411201China

Lanthanide-based upconversion core-shell NaGdF4 nanocrystals with strong upconversion luminescence and biocompatibility were synthesized by the solvothermal *** multicolor upconversion emission of these NaGdF4 nanoparticles could be easily obtained by controlling the core-shell *** multicolor core-shell NaGdF4 upconversion nanocrystals could be employed as fluorescent probes for imaging the mouse hair,by which the porous and scalelike structure of the mouse hair were presented ***,it was directly shown by fluorescent signals that the mouse hair could resist the corrosion of the strong acid even when the concentration of hydrochloric acid was increased to 36.5%,but could not avoid the carbonization at high temperature of 400 *** procedure based on upconversion fluorescent nanoprobes opens a novel route for investigating the basic physical structure and chemical properties of biological tissue and organism.

关键词： upconversion multicolor imaging mouse hair rare earths

Remarkable red-shift of upconversion luminescence and anti-ferromagnetic coupling in NaLuF_4:Yb^(3+)/Tm^(3+)/Gd^(3+)/Sm^(3+) bifunctional microcrystals

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Journal of Rare Earths 2016年第2期34卷 166-173页

作者：胡仕刚刘云新吴笑峰唐志军李志明颜焕元陈增辉胡盼余意 School of Information and Electrical Engineering Hunan University of Science and Technology Department of Physics and Electronic Science Hunan University of Science and Technology School of Information Science and Engineering University of Jinan College of Mechanical and Electrical Engineering Hunan University of Science and Technology

Lanthanide doped bifunctional materials are potentially important for developing multifunctional devices. Here, NaLuF4:Yb3+/Tm3+/Gd3+/Sm3+ optical-magnetic bifunctional microcrystals were successfully synthesized by hydrothermal method, which could emit ~480 nm blue light from the1G4→3H6 electronic transition and ~800 nm infrared light from the3H4→3H6electronic transition of Tm3+ ion, under the excitation of 980 nm infrared light. By doping Sm3+ ion into NaLuF4:Yb3+/Tm3+/Gd3+, the infrared emission peak centered at 800 nm would shift obviously to longer wavelength. This indicated that Sm3+ ion could efficiently tune the energy level gaps of Tm3+ ions in NaLuF4 host which was demonstrated based on the crystal field theory. In addition, these NaLuF4:Yb3+/Tm3+/Gd3+/Sm3+ microcrystals presented unique ferromagnetic property instead of usually reported paramagnetic prop-erty. Importantly, the ferromagnetic property decreased with increasing the concentration of Gd3+ ion. This was in good agreement with Swift’s theoretical investigation that the coexistence of light rare earth (Gd3+) and heavy rare earth (Yb3+/Tm3+) would lead to the anti-ferromagnetic coupling in the sub-lattices.

关键词： upconversion luminescence magnetic property bifunctional rare earth doping

对称双栅高斯掺杂应变Si金属氧化物半导体场效应管的二维解析模型

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中南大学学报（自然科学版） 2016年第4期47卷 1203-1208页

作者：李劲吴笑峰席在芳胡仕刚李目湖南科技大学信息与电气工程学院湖南湘潭411201

基于扩散、阈值调整和离子注入等工艺过程导致器件的沟道区的掺杂分布不均匀,提出对称双栅高斯掺杂应变硅MOSFET器件,并对其相关特性进行研究。通过对沟道二维泊松方程求解建立该器件结构的表面势和阈值电压模型,分析弛豫SiGe层的Ge组... 详细信息

基于扩散、阈值调整和离子注入等工艺过程导致器件的沟道区的掺杂分布不均匀,提出对称双栅高斯掺杂应变硅MOSFET器件,并对其相关特性进行研究。通过对沟道二维泊松方程求解建立该器件结构的表面势和阈值电压模型,分析弛豫SiGe层的Ge组分和掺杂偏差σn对表面势和阈值电压的影响。此外,还对比分析高斯掺杂对称双栅应变硅MOSFET器件和均匀掺杂对称双栅应变硅MOSFET器件的表面势和阈值电压。研究结果表明:阈值电压随应变Si膜中Ge组分的增加而降低;表面势和阈值电压随偏差σn的增加而减小;高斯掺杂对称双栅应变硅MOSFET器件和均匀掺杂对称双栅应变硅MOSFET器件的表面势和阈值电压相差较大,表明非均匀掺杂对器件表面势和阈值电压等影响较大。

关键词：高斯掺杂应变Si 阈值电压

Upconversion nanoparticles for differential imaging of plant cells and detection of fluorescent dyes

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Journal of Rare Earths 2016年第2期34卷 208-220页

作者：吴笑峰胡盼胡仕刚陈增辉严焕元唐志军席在芳余意戴港涛刘云新 School of Information and Electrical Engineering Department of Physics and Electrical Science College of Mechanical and Electrical Engineering Hunan University of Science and TechnologyXiangtan 411201China INPAC-Institute for Nanoscale Physics and Chemsitry KU LeuvenCelestijnenlaan 200D B-3001Belgium

Upconversion NaLuF4 nanoparticles were synthesized by the solvothermal method which could emit multicolor visible light under the excitation of 980 nm near-infrared (NIR) photons. These upconversion nanoparticles (UCNPs) with an acidic ligand could rapidly capture the basic rhodamine-B (RB) in plant cells to generate a close UCNPs@RB system. RB could efficiently absorb the green fluorescence from NaLuF4:18 mol.%Yb3+,2 mol.%Er3+ UCNPs and then emitted red light in the UCNPs@RB system by a robust luminescence resonance energy transfer (LRET) from UCNPs to RB. The detection limit of RB with these upconversion fluo-rescent nanoprobes could reach 0.25μg/cm3 in plant cell even under an ultra low excitation power source of 0.2 W/mm2. This LRET phenomenon was also extended to NaLuF4:18 mol.%Yb3+,0.5 mol.%Tm3+@Sodium fluorescein (SF) system. In addition, the differ-ential imaging could be achieved by successively incubating plant cells with fluorescent dyes and UCNPs. The fluorescent dyes ag-gregated in cell wall while UCNPs with surface modification distributed both in cell wall and cytoplasm, so that UCNPs@Dyes formed in cell walls which could emit multicolor light by LRET which was different from the emission in cytoplasm with only UCNPs.

关键词： upconversion luminescence fluorescent dye cell imaging detection rare earths

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小波变换的单开关电流积分器设计实现方法

中南大学学报（自然科学版） 2018年第2期49卷 378-383页

作者：李目吴笑峰席在芳李海鸥胡仕刚湖南科技大学信息与电气工程学院湖南湘潭411201 桂林电子科技大学广西精密导航技术与应用重点实验室广西桂林541004

针对小波变换的模拟电路实现问题,提出一种基于单开关电流积分器的模拟小波变换电路设计新方法。根据小波变换的模拟滤波器实现原理,以某一带通滤波器传递函数为例,首先,基于小波函数的容许条件,证明该网络函数为母小波函数;然后,采用... 详细信息

针对小波变换的模拟电路实现问题,提出一种基于单开关电流积分器的模拟小波变换电路设计新方法。根据小波变换的模拟滤波器实现原理,以某一带通滤波器传递函数为例,首先,基于小波函数的容许条件,证明该网络函数为母小波函数;然后,采用单开关电流积分器为基本单元设计冲激响应为该母小波的带通滤波器,通过调节滤波器电路时钟频率获得不同尺度小波函数实现小波变换。研究结果表明:该方法实现小波变换具有无需小波函数逼近过程、设计精度高、电路结构简单、小波函数尺度易于调节等特点,适合于低压、低功耗和实时工程应用。

关键词：小波变换开关电流积分器开关电流滤波器电路设计

任意实小波函数的高阶开关电流滤波器通用实现方法

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中南大学学报（自然科学版） 2016年第10期47卷 3417-3423页

作者：李目吴笑峰席在芳胡仕刚李劲邬书跃湖南科技大学信息与电气工程学院湖南湘潭411201 湖南涉外经济学院信息科学与工程学院湖南长沙410205

通过对实小波函数的模拟滤波器实现原理进行分析,将其实现过程分解为实小波函数逼近和小波滤波器设计2步,提出一种适合任意实小波函数的高阶开关电流滤波器通用综合方法,并设计具体的电路模型。首先,基于网络系统综合理论,构建实小波函... 详细信息

通过对实小波函数的模拟滤波器实现原理进行分析,将其实现过程分解为实小波函数逼近和小波滤波器设计2步,提出一种适合任意实小波函数的高阶开关电流滤波器通用综合方法,并设计具体的电路模型。首先,基于网络系统综合理论,构建实小波函数的通用优化逼近模型;然后,以开关电流双线性积分器和电流镜为基本单元设计出冲激响应为实小波逼近函数的通用多环反馈结构滤波器,通过调节开关电流滤波器的时钟频率获得不同尺度小波函数。以开关电流实Morlet小波滤波器设计为例验证该通用方法的正确性。

关键词：开关电流电路小波函数函数逼近小波滤波器设计