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Biomass-based Carbon Dots as Peroxidase Mimics for Colorimetric Detection of Glutathione and L-Cysteine

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Chemical Research in Chinese Universities 2022年第6期38卷 1446-1452页

作者： LIU Junxue WANG Yufei ma Wenyan ZONG Siyu LI Jiyang State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun130012P.R.China

Biomass-carbon dots(named as B-CDs) have been successfully prepared via facile one-step hydrothermal reflux treatment at a low temperature from passion fruit peel. The as-prepared B-CDs had a uniform sphere morphology and size of 1–3 nm, which possessed rich nitrogen/oxygen-containing functional groups. B-CDs could imitate peroxidase and accelerate the reaction process of H2O_(2) oxidizing the substrate 3,3’,5,5’-tetramethylbenzidine(TMB), which caused an obvious color change in the solution due to the oxidization of achromic TMB into blue oxidation product(ox-TMB) with an absorption peak at 652 nm. Furthermore, the product could be further reduced to native colorless TMB by the reducing agent glutathione or L-Cysteine. Thus, depending on the peroxidase-like properties of B-CDs, we developed a colorimetric approach to detecting both glutathione and L-Cysteine, which showed superior selective and sensitive detection towards glutathione and L-Cysteine in a linear range of 0–20 µmol/L. The limits of detection were 0.62 and 0.58 µmol/L, respectively.

关键词： Carbon dot Biomass Colorimetry Glutathione Cysteine

High performance photodetector based on few-layer MoTe_(2)/CdS_(0.42)Se_(0.58) flake heterojunction

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Frontiers of physics 2024年第4期19卷 91-101页

作者： Ran ma Qiuhong Tan Peizhi Yang Yingkai Liu Qianjin Wang College of Physics and Electronic Information Yunnan Normal UniversityKunming 650500China Yunnan Provincial Key Laboratory for Photoelectric Information Technology Yunnan Normal UniversityKunming 650500China Key Laboratory of Advanced Technique&Preparation for Renewable Energy materials Ministry of EducationYunnan Normal UniversityKunming 650500China

Two-dimensional(2D)transition metal dichalcogenides have been extensively studied due to their fascinating physical properties for constructing high-performance ***,their relatively low responsivities,current on/off ratios and response speeds have hindered their widespread ***,we fabricated a high-performance photodetector based on few-layer MoTe_(2) and CdS_(0.42)Se_(0.58) flake *** photodetector exhibited a high responsivity of 7221 A/W,a large current on/off ratio of 1.73×10^(4),a fast response speed of 90/120μs,external quantum efficiency(EQE)reaching up to 1.52×10^(6)%and detectivity(D*)reaching up to 1.67×10^(15) *** excellent performance of the heterojunction photodetector was analyzed by a photocurrent mapping test and first-principle ***,the visible light imaging function was successfully attained on the MoTe_(2)/CdS_(0.42)Se_(0.58) photodetectors,indicating that the device had practical imaging application *** findings provide a reference for the design of ultrahighperformance MoTe_(2)-based photodetectors.

关键词： photodetector MoTe_(2) heterojunction visible light imaging first-principles calculations

Sparse Least Square Support Vector machines based on Random Entropy 36

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Sparse Least Square Support Vector Machines based on Random ...

Microstructure and corrosion behavior of the heat affected zone of a stainless steel 308L-316L weld joint

第36届中国控制会议

作者： Wenlu ma Han Liu Faculty of Automation and Information Engineering Xi'an University of Technology Shaanxi Key Lab. of Complex System Control and Intelligent Information Processing Faculty of Automation and Information EngineeringXi’an University of Technology

ISBN: (纸本)9781538629185

Least squares support vector machines（LSSVM） has a good performance in small data samples, but can’t solve the large-scale sample problems. In this paper, large data set sparse least squares support vector machines model based on stochastic entropy is proposed, and it can be applied to large-scale data samples. Firstly, the large-scale data set is divided into several subsets. Then the entropy method is used to the sparse samples in each subset. Finally, we use sparse samples sets as training samples, and use least squares support vector machine algorithm to train. The results show that the sparse least squares support vector machine model based on entropy can effectively solve the problem of large-scale data.

关键词： Sparsity LSSVM Large-scale data Random Entropy

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Journal of materials Science & Technology 2018年第10期34卷 1823-1834页

作者： Cheng ma Qunjia Peng Jinna Mei En-Hou Han Wei Ke Key Laboratory of Nuclear materials and Safety Assessment. Institute of Metal Research Chinese Academy of Science Shenyang 110016 China University of Chinese Academy of Sciences Beifing 100049 China Suzhou Nuclear Power Research Institute Suzhou 215004 China

Microstructure of the heat affected zone （HAZ） of a 308L-316L stainless steel （SS） weld joint and its corrosion behavior in high temperature water were studied. Peak of the residual strain was observed to approach to the fusion boundary in the HAZ while the strain increased from the top to root areas of the HAZ. The root area of the HAZ shows a lower corrosion resistance in high temperature water than the top and middle areas of the HAZ. This is attributed to a higher level of residual strain in association with a higher density of tangled dislocations in the top area of the HAZ. The results suggest that the residual strain in the HAZ could also promote the SCC through its effect on corrosion, in addition to that on the local microstructure and mechanical property of the steel.

关键词： Stainless steel HAZ Weld joint Corrosion High temperature water

Titanium Isotope Analysis of Igneous Reference materials using a Double-spike MC-ICP-MS Method

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Acta Geologica Sinica(English Edition) 2022年第2期96卷 517-524页

作者： LI Jin TANG Suohan ZHU Xiangkun ma Jianxiong ZHAO Xinmiao MNR Key Laboratory of Isotope Geology Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

Ti separation was achieved by ion-exchange chromatography using Bio-Rad AG 1-X8 anion-exchange and DGA *** high-Fe/Ti and high-Mg/Ti igneous samples,a three-column procedure was required,whereas a two-column procedure was used for low-Fe/Ti and low-Mg/Ti igneous *** Ti isotopes were analysed by MC-ICP-MS,and instrumental mass bias was corrected using a ^(47)Ti-^(49)Ti double-spike *** ^(47)Ti-^(49)Ti double-spike and SRM 3162a were calibrated using SRM 979-Cr,certificated value ^(53)Cr/^(52)Crt rue=*** interference was evaluated by analysing Alfa-Ti doped with Na,Mg,Ca,and Mo,and results indicate that high concentrations of Na and Mg have no significant effect on Ti isotope analyses;however,Ca and Mo interferences lead to erroneousδ^(49/47)Ti values when Ca/Ti and Mo/Ti ratios exceed 0.01 and 0.1,*** isotopic compositions were determined for 12 igneous reference materials,BCR-2,BHVO-2,GBW07105,AGV-1,AGV-2,W-2,GBW07123,GBW07126,GBW07127,GBW07101,JP-1,and *** yieldδ^(49/47)Ti(‰)of−0.035±0.022,−0.038±0.031,0.031±0.022,0.059±0.038,0.044±0.037,0.000±0.015,0.154±0.044,−0.044±0.018,0.010±0.022,0.064±0.043,0.169±0.034,and−0.047±0.025(relative to OL-Ti,±2SD),respectively;of which isotopic compositions of DTS-2b,JP-1,GBW07101,GBW07105,GBW07123,GBW07126,and GBW07127 are reported for the first *** Alfa-Ti was analysed repeatedly over a ten-month period,indicating a reproducibility of±0.047(2SD)forδ^(49/47)Ti,similar to the precisions obtained for geochemical reference materials.

关键词： Ti isotope double-spike mass bias correction MC-ICP-MS reference material

Recent developments in superjunction power devices

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Journal of Semiconductors 2024年第11期45卷 18-35页

作者： Chao ma Weizhong Chen Teng Liu Wentong Zhang Bo Zhang State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of ChinaChengdu 610054China

Superjunction(SJ)is one of the most innovative concepts in the field of power semiconductor devices and is often referred to as a"milestone"in power *** balanced charge field modulation mechanism breaks through the strong dependency between the doping concentration in the drift region and the breakdown voltage V_(B)in conventional *** results in a reduction of the trade-off relationship between specific on-resistance R_(on,sp)and V_(B)from the conventional R_(on,sp)∝V_(B)^(2.5)to R_(on,sp)∝W·V_(B)^(1.32),and even to R_(on,sp)∝W·V_(B)^(1.03).As the exponential term coefficient decreases,R_(on,sp)decreases with the cell width W,exhibiting a development pattern reminiscent of"Moore's Law".This paper provides an overview of the latest research developments in SJ power semiconductor ***,it introduces the minimum specific on-resistance R_(on,min)theory of SJ devices,along with its combination with special effects like 3-D depletion and tunneling,discussing the development of R_(on,min)theory in the wide bandgap SJ ***,it discusses the latest advancements in silicon-based and wide bandgap SJ power ***,it introduces the homogenization field(HOF)and high-K voltage-sustaining layers derived from the concept of SJ charge *** has made significant progress in device performance,reliability,and integration,and in the future,it will continue to evolve through deeper integration with different materials,processes,and packaging technologies,enhancing the overall performance of semiconductor power devices.

关键词： super junction silicon limit power semiconductor device design theory

Comparative population genetic analyses suggest hybrid origin of Rhododendron pubicostatum,an endangered plant species with extremely small populations endemic to Yunnan,China

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Plant Diversity 2020年第4期42卷 312-318页

作者： Xuemei Zhang Hantao Qin Weijia Xie Yongpeng ma Weibang Sun Yunnan Key Laboratory for Integrative Conservation of Plant Species with Extremely Small Populations Kunming Institute of BotanyChinese Academy of Sciences(CAS)Kunming650201YunnanChina Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of Sciences(CAS)Kunming650201China University of Chinese Academy of Sciences 100049BeijingChina Flower Research Institute Yunnan Academy of Agriculture SciencesKunming650201China

Gene flow between sympatric congeneric plants is thought to be very common and may pose serious threats to endangered *** the present study,we evaluate the genetic diversity and divergence of three sympatric Rhododendron species in Jiaozi Mountain using newly developed microsatellites through the Illumina MiSeq sequencing *** diversity of all three Rhododendron species studied was moderate in comparison to genetic parameters previously reported from species of this ***,genetic structure analysis of the three species identified a possible hybrid origin of the threatened *** sympatry should be considered a unimodal hybrid zone,since *** is predominant *** hybrid zones are uncommon in Rhododendron,despite the fact that hybridization frequently occurs in the *** pertaining to the conservation of *** resulting from admixture of genetic material from its parental species are discussed.

关键词： Rhododendron pubicostatum Plant Species with Extremely Small Populations(PSESP) Microsatellite markers Illumina MiSeq sequencing Conservation management

Diffusive representation of Riemann-Liouville fractional integrals and derivatives 36

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Diffusive representation of Riemann-Liouville fractional int...

Optically pumped semiconductor nanowire lasers

第36届中国控制会议

作者： Yuxiang Guo Baoli ma The Seventh Research Division Beijing University of Aeronautics and Astronautics

ISBN: (纸本)9781538629185

This paper presents a novel equivalent description of fractional-order integrals and derivatives via an auxiliary integral function of two *** the concept of Laguerre integration,a novel approximate scheme for the resulting infinite dimensional state space model is derived.A simple example with numerical simulations is provided to show the superiority and effectiveness of the proposed method in comparison with some related works from the previous results.

关键词： Riemann-Liouville integral Riemann-Liouville derivative fractional-order system Mittag-Leffler function Laguerre integration

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Frontiers of Optoelectronics 2012年第3期5卷 239-247页

作者： Yaoguang ma Limin TONG State Key Laboratory of Modem Optical Instrumentation Department of Optical Engineering Zhejiang University Hangzhou 310027 China

This paper reviews our recent work on fabrication, optical characterization and lasing application of semiconductor nanowires, with brief introduction of related work from many other groups.

关键词： semiconductor nanowire nanowire laser,optical pump microfiber