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New materials and designs for 2D-based infrared photodetectors

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Nano Research 2023年第2期16卷 3074-3103页

作者： Huitian guo Weihong qi State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsNorthwestern Polytechnical UniversityXi’an 710072China Shandong Laboratory of Yantai Advanced Materials and Green Manufacturing Yantai 264006China

Infrared photodetectors have attracted much attention considering their wide civil and military ***-dimensional(2D)materials offer new opportunities for the development of costless,high-level integration and high-performance infrared *** the advent of a broad investigation of infrared photodetectors based on graphene and transition metal chalcogenides(TMDs)exhibiting unique properties in recent decades,research on the better performance of 2D-based infrared photodetectors has been extended to a larger scale,including explorations of new materials and artificial structure *** this review,after a brief background introduction,some major working mechanisms,including the photovoltaic effect,photoconductive effect,photogating effect,photothermoelectric effect and bolometric effect,are briefly ***,the discussion mainly focuses on the recent progress of three categories of 2D materials beyond graphene and *** transition metal dichalcogenides,black phosphorus and arsenic black phosphorous and 2D ternary compounds are great examples of explorations of mid-wavelength or even long-wavelength 2D infrared ***,four types of rational structure designs,including type-II band alignments,photogating-enhanced designs,surface plasmon designs and ferroelectric-enhanced designs,are discussed to further enhance the performance via diverse mechanisms,which involve the narrower-bandgap-induced interlayer exciton transition,gate modulation by trapped carriers,surface plasmon polaritons and ferroelectric polarization in ***,applications including imaging,flexible devices and on-chip integration for 2D-based infrared photodetectors are ***,a summary of the state-of-the-art research status and personal discussion on the challenges are delivered.

关键词： two-dimensional(2D)materials infrared photodetectors noble transition metal dichalcogenides black phosphorus layered ternary compounds structure designs

Screening of the ubiquitin-proteasome system activators for anti-Alzheimer’s disease by the high-content fluorescence imaging system

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Chinese Journal of Natural Medicines 2022年第1期20卷 33-42页

作者： WANG Yi-Ling YOU jing CAO jing-Jie LI Wei jing Liu-Yang MEI qi-Bing WU An-guo Sichuan Key Medical Laboratory of New Drug Discovery and Drugability Evaluation Luzhou Key Laboratory of Activity Screening and Druggability Evaluation for Chinese Materia MedicaSchool of PharmacyEducation Ministry Key Laboratory of Medical ElectrophysiologySouthwest Medical UniversityLuzhou 646000China Luzhou New Drug Evaluation and Research Center Luzhou 646000China

Ubiquitin-proteasome system(UPS)plays an important role in neurodegenerative diseases,such as Alzheimer’s disease(AD),Parkinson’s disease(PD),and Huntington’s disease(HD).The discovery of UPS activators for anti-neurodegenerative diseases is becoming increasingly *** this study,we aimed to identify potential UPS activators using the high-throughput screening method with the high-content fluorescence imaging system and validate the neuroprotective effect in the cell models of *** first,stable YFP-CL1 HT22 cells were successfully constructed by transfecting the YFP-CL1 plasmid into HT22 cells,together with G418 *** degradation activity of the test compounds via UPS was monitored by detecting the YFP fluorescence intensity reflected by the ubiquitin-proteasome degradation signal *** employing the high-content fluorescence imaging system,together with stable YFP-CL1 HT22 cells,the UPS activators were successfully screened from our established TCM *** representative images were captured and analyzed,and quantification of the YFP fluorescence intensity was performed by flow ***,the neuroprotective effect of the UPS activators was investigated in pEGFP-N1-APP(APP),pRK5-EGFP-Tau P301L(Tau P301L),or pRK5-EGFP-Tau(Tau)transiently transfected HT22 cells using fluorescence imaging,flow cytometry,and Western *** conclusion,our study established a high-content fluorescence imaging system coupled with stable YFP-CL1 HT22 cells for the highthroughput screening of the UPS *** compounds,namely salvianolic acid A(SAA),salvianolic acid B(SAB),and ellagic acid(EA),were identified to significantly decrease YFP fluorescence intensity,which suggested that these three compounds are UPS *** identified UPS activators were demonstrated to clear AD-related proteins,including APP,Tau,and Tau ***,these findings provide a novel insight into the discovery and development of anti-AD drugs.

关键词： Ubiquitin-proteasome system High-content fluorescence imaging system Traditional Chinese medicine Alzheimer’s disease YFP-CL1 HT22 cells

UNIFORM SUPERAPPROXIMATION OF THE DERIVATIVE OF TETRAHEDRAL QUADRATIC FINITE ELEMENT APPROXIMATION

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Journal of Computational Mathematics 2005年第1期23卷 75-82页

作者： jing-hongLiu qi-dingZhu InstituteofAppliedMathematics HunanUniversityChangsha~10082China)(SchoolofMathematicsandComputerScienceHunanNormalUniversityChangsha410081China SchoolofMathematicsandComputerScience HunanNormalUniversityChangsha410081China

In this paper,we will prove the derivative of tetrahedral quadratic finite element ap-proximation is superapproximate to the derivative of the quadratic Lagrange interpolant of the exact solution in the L^∞-norm, which can be used to enhance the accuracy of the derivative of tetrahedral quadratic finite element approximation to the derivative of the exact solution。

关键词： tetrahedron superapproximation finite element

Dynamic recrystallization behavior of Fe–20Cr–30Ni–0.6Nb–2Al–Mo alloy

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Rare Metals 2019年第2期38卷 181-188页

作者： Rui Luo qi Zheng jing-jing Zhu Shun guo Dong-Sheng Li Gui-Fang Xu Xiao-Nong Cheng School of Materials Science and Engineering Jiangsu University

Single-pass compression tests of an aluminaforming austenite(AFA) alloy(Fe–20Cr–30Ni–0.6Nb–2Al–Mo) were performed using a Gleeble-3500 thermal–mechanical simulator. By combining techniques of electron back-scattered diffraction(EBSD) and transmission electron microscopy(TEM), the dynamic recrystallization(DRX) behavior of the alloy at temperatures of 950–1100 ℃ and strain rates of 0.01–1.00 s^(-1) was investigated. The regression method was adopted to determine the thermal deformation activation energy and apparent stress index and to construct a thermal deformation constitutive model. Results reveal that the flow stress is strongly dependent on temperature and strain rate and it increases with temperature decreasing and strain rate increasing. The DRX phenomenon occurs more easily at comparably higher deformation temperatures and lower strain rates. Based on the method for solving the inflection point via cubic polynomial fitting of strain hardening rate(h) versus strain(e) curves, the ratio of critical strain(ec) to peak strain(ep) during DRX was precisely predicted. The nucleation mechanisms of DRX during thermal deformation mainly include the strain-induced grain boundary(GB)migration, grain fragmentation, and subgrain coalescence.

关键词： Alumina-forming austenitic alloy Constitutivemodel Dynamic recrystallization Critical strain Straininduced grain boundary migration

System Identification and Parameter Self-Tuning Controller on Deep-Sea Mining Vehicle

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China Ocean Engineering 2023年第1期37卷 53-61页

作者： WENG qi-wang YANG Jian-min LIANG qiong-wen MAO jing-hang guo Xiao-xian SJTU Yazhou Bay Institute of Deepsea SCI-TECH Sanya 572000China State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China Institute of Marine Equipment Shanghai Jiao Tong UniversityShanghai 200240China

System identification is a quintessential measure for real-time analysis on kinematic characteristics for deep-sea mining vehicle, and thus to enhance the control performance and testing efficiency. In this study, the system identification algorithm, recursive least square method with instrumental variables(IV-RLS), is tailored to model ‘Pioneer I’, a deep-sea mining vehicle which recently completed a 1305-meter-deep sea trial in the Xisha area of the South China Sea in August, 2021. The algorithm operates on the sensor data collected from the trial to obtain the vehicle’s kinematic model and accordingly design the parameter self-tuning controller. The performances demonstrate the accuracy of the model, and prove its generalization capability. With this model, the optimal controller has been designed, the control parameters have been self-tuned, and the response time and robustness of the system have been optimized,which validates the high efficiency on digital modelling for precision control of deep-sea mining vehicles.

关键词： deep-sea mining system identification parameter self-tuning controller digital modeling

Role of mountains and rivers in the formation of logistics enterprises'spatial pattern in the central urban areas of Chongqing

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Journal of Mountain Science 2022年第7期19卷 2060-2074页

作者： LIU Si-jing ZHU Cheng-jia HE Nan-nan LI guo-qi School of Transportation and Logistics Southwest Jiaotong UniversityChengdu611756China National Engineering Laboratory of Integrated Transportation Big Data Application Technology Chengdu611756China National United Engineering Laboratory of Integrated and Intelligent Transportation Chengdu611756China

The complex landforms of a Shan-shui City(Shan-shui refers to mountains and rivers)significantly impact the selection of locations for logistics *** paper takes Chongqing,one of the most typical Shan-shui Cities in China,as the research object,and adopts spatial analysis methods and a mediating effect model,to explore the role of mountains and rivers in the formation of logistics enterprises’spatial pattern on the street *** study results reveal that 90% of the logistics enterprises in the central urban areas of Chongqing are located in the low-altitude area below 353m above sea level,and distributed in a north-south direction along the mountains,as a result of blockage by mountain ranges,such as those of Zhongliang Mountain and Tongluo *** than 70% of the logistics enterprises are located less than 5 km from either the Yangtze River or Jialing River,spreading along the *** addition,more than half of the logistics enterprises in commercial and financial,and residential land are located within the urban core area,while 80.83% of the logistics enterprises located in warehousing land and industrial land are concentrated in the urban expansion *** areas with high land prices,the negative effect of altitude on logistics enterprise agglomeration is weakened,while the promotion effect of river proximity on logistics enterprise agglomeration is *** the urban core area with the advantage of low altitude and proximity to the Jialing and Yangtze Rivers,the role of mountains and rivers on logistics enterprises is not apparent;in contrast,in the urban expansion area with more complex landforms,land price can be an effective means for the government to macro-manage the spatial pattern of logistics enterprises in a Shan-shui City.

关键词： Logistics enterprise Spatial pattern Influencing factors Driving mechanism Chongqing

Synthesis and characterization of Co_3O_4 prepared from atmospheric pressure acid leach liquors of nickel laterite ores

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International Journal of Minerals,Metallurgy and Materials 2018年第1期25卷 20-27页

作者： Long Meng Zhan-cheng guo jing-kui Qu Tao qi qiang guo Gui-hua Hou Peng-yu Dong Xin-guo Xi National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Key Laboratory of Green Process and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Zhengzhou Institute of Emerging Technology Industries Zhengzhou 450000China Key Laboratory for Advanced Technology in Environmental Protection of Jiangsu Province Yancheng Institute of TechnologyYancheng 224051China Jiangsu Collaborative innovation Center for Ecological Building Materials and Environmental Protection Equipments Yancheng Institute of TechnologyYancheng 224051China

A chemical precipitation-thermal decomposition method was developed to synthesize Co3O4 nanoparticles using cobalt liquor obtained from the atmospheric pressure acid leaching process of nickel laterite ores. The effects of the precursor reaction temperature, the concentration of Co2＋, and the calcination temperature on the specific surface area, morphology, and the electrochemical behavior of the ob- tained Co304 particles were investigated. The precursor basic cobaltous carbonate and cobaltosic oxide products were characterized and ana- lyzed by Fourier transform infrared spectroscopy, thermogravimetric differential thermal analysis, X-ray diffraction, field-emission scanning electron microscopy, specific surface area analysis, and electrochemical analysis. The results indicate that the specific surface area of the Co3O4particles with a diameter of 30 rim, which were obtained under the optimum conditions of a precursor reaction temperature of 30℃, 0.25 mol/L Co2＋, and a calcination temperature of 350℃, was 48.89 m2/g. Electrodes fabricated using Co3O4 nanoparticles exhibited good electrochemical properties, with a specific capacitance of 216.3 F/g at a scan rate of 100 mV/s.

关键词： nickel laterite ores, acid leach liquors synthesis cobaltosic oxide characterization

Total Ionizing Dose Effect and Failure Mechanism of Digital Signal Processor

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Chinese Journal of Electronics 2021年第5期30卷 986-990页

作者： YU Xin LU Wu LI Xiaolong LIU Mohan WANG Xin SUN jing guo qi Xinjiang Technical Institute of Physics and Chemistry Laboratory of Solid State Radiation Physics

Ionizing radiation effect and failure mechanism of Digital signal processor(DSP) is studied through test-board and automatic test equipment to find the relationship between system function failure and parameter degradation. Static bias is more sensitive than dynamic bias when DSP is tested on-line during radiation. Core current, high-Z leakage current and timing parameter are sensitive to ionizing radiation. No enhanced low-dose-rate sensitivity is found by comparing experiment results under high and low dose rate *** memory interface and Timer are deduced to be the sensitive module by step radiation and analysis basing full parameter test in Verigy 93000. The timing parameter degradation have a strong correlation to these module functions. And the degeneration mechanism is analysed on inverter through Hspice simulation which indicate the leakage circuit caused by radiation can lead a delay to the digital signal propagating. The parasitical capacitance among long connections make it worse to the data transmission around DSP, field programmable gate array and memory. Then an early function failure occurs in test board than Verigy 93000. This work provide support to systematic radiation hardness design and hardness assurance/lot acceptance testing in space applications.

关键词： Verigy 93000 analysis basing full parameter test digital signal propagating radiation effect radiation effects DSP external memory interface leakage currents early function failure leakage circuit test board sensitive module system function failure high dose rate radiation static bias automatic test equipment timing parameter degradation low dose rate radiation field programmable gate array enhanced low-dose-rate sensitivity Digital signal processor degeneration mechanism systematic radiation hardness design radiation hardening (electronics) field programmable gate arrays integrated circuit testing ionizing radiation dynamic bias module functions step radiation digital signal processing chips failure mechanism test-board

Studying the localized CP violation and the branching fraction of the B^0→K^-π^+π^+π^-decay

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Chinese Physics C 2020年第10期44卷 51-58页

作者： jing-Juan qi Zhen-Yang Wang jing Xu Xin-Heng guo Junior College Zhejiang Wanli UniversityZhejiang 315101China Physics Department Ningbo UniversityZhejiang 315211China Department of Physics Yantai UniversityYantai 264005China College of Nuclear Science and Technology Beijing Normal UniversityBeijing 100875China

In this work,we study the localized CP violation and the branching fraction of the four-body decay^ˉB 0→K^−π^+π^−π^+by employing a quasi-two-body QCD factorization *** the interference of^ˉB 0→ˉK^∗0(700)ρ0(770)→K^−π^+π^−π^+and^ˉB 0→ˉK∗(892)f0(500)→K^−π^+π^−π^+channels,we predict ACP(^ˉB 0→K^−π^+π^−π^+)∈[0.15,0.28]and B(^ˉB 0→K^−π^+π^−π^+)∈[1.73,5.10]×10^−7,respectively,which shows that the interference mechanism of these two channels can induce the localized CP violation to this four-body ***,within the two quark model framework for the scalar mesons f0(500)andˉK^∗0(700),we calculate the direct CP violations and branching fractions of the^ˉB 0→ˉK^∗0(700)ρ0(770)and^ˉB 0→ˉK∗(892)f0(500)decays,*** corresponding results are ACP(^ˉB 0→ˉK^∗0(700)ρ0(770))∈[0.20,0.36],ACP(^ˉB 0→ˉK∗(892)f0(500))∈[0.08,0.12],B(^ˉB 0→ˉK^∗0(700)ρ0(770)∈[6.76,18.93]×10^−8 and B(^ˉB 0→ˉK∗(892)f0(500))∈[2.66,4.80]×10^−6,indicating that the CP violations of these two-body decays are both positive and the branching fractions quite *** studies provide a new way to investigate the aforementioned four-body decay and can be helpful in clarifying the configuration of the structure of the light scalar meson.

关键词： decays of bottom mesons CP violation perturbative calculations