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A multi-sensor-based distributed real-time measurement system for glacier deformation

Journal of Mountain Science 2023年第10期20卷 2913-2927页

作者： DONG Han-chuan liU Shuang PANG li-li TAO Zhi-gang fang li-de ZHANG Zhong-hua li Xiao-ting College of Quality and Technical Supervision Hebei UniversityBaoding 071002China Technology Innovation Center for Geological Environment Monitoring Ministry of Natural ResourcesBaoding 071051China Center for Hydrogeology and Environmental Geology Survey China Geological SurveyChina Geological SurveyBaoding 071051China Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610299China School of Mechanics and Civil Engineering China University of Mining and TechnologyBeijing 100083China

Glacier disasters occur frequently in alpine regions around the world,but the current conventional geological disaster measurement technology cannot be directly used for glacier disaster ***,in this study,a distributed multi-sensor measurement system for glacier deformation was established by integrating piezoelectric sensing,coded sensing,attitude sensing technology and wireless communication *** traditional Modbus protocol was optimized to solve the problem of data identification confusion of different acquisition *** indoor wireless transmission,adaptive performance analysis,error measurement experiment and landslide simulation experiment,the performance of the measurement system was analyzed and *** unmanned aerial vehicle technology,the reliability and effectiveness of the measurement system were verified on the site of Galongla glacier in southeastern Tibet,*** results show that the mean absolute percentage errors were only 1.13%and 2.09%for the displacement and temperature,*** distributed glacier deformation real-time measurement system provides a new means for the assessment of the development process of glacier disasters and disaster prevention and mitigation.

关键词： Glacier disasters Distributed deformation measurement Multi-sensor Real-time LoRa Data adaptive.

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Measurement of CO_(2) concentration based on supercontinuum laser absorption spectroscopy

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Optoelectronics Letters 2021年第3期17卷 176-182页

作者： li Hong-lian DI Shuai li Wen-duo LüWen-jing WANG Fan fang li-de College of Quality and Technical Supervision Hebei UniversityBaoding 071002China National and Local Joint Engineering Center of Measuring Instruments and Metrology Systems Baoding 071002China College of Chemistry&Environmental Science Hebei UniversityBaoding 071002China

The concentrations of CO_(2) were measured by the supercontinuum laser at normal temperature and variable temperature accurately in this paper. The absorption spectra of CO_(2) at different concentrations(1.2%—9.0%) were measured in the wavelength range of 1 425—1 445 nm under the optical path of 26.4 m at 293 K and 1 atm. The experimental results showed that the positions of the primary and secondary absorption peaks(1 432 nm, 1 437 nm) were consistent with the HITRAN database. A linear model of concentration and signal intensity at 1 432 nm was established. The maximum relative error of the concentration measurement was 3.3%. The line intensities of 99.9% CO_(2) in the 1 425—1 445 nm at different temperatures(298—373 K, interval of 15 K) were measured. The influence of temperature changes on the concentration measurement result was corrected and the relative error of the concentration measurement was reduced to 1.4%. Finally, the source of the uncertainty of the entire spectrum measurement system was analyzed and evaluated. This paper demonstrate that the supercontinuum laser can achieve the long-distance measurement of the CO_(2) under normal temperature or variable temperature environment accurately, which provide an important reference for the long-distance gas detection on site and simultaneous detection of multi-component gases.

关键词： laser absorption concentration

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Plasma characteristics and quantitative analysis of Pb and Ni in soil based on liBS technology

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Optoelectronics Letters 2020年第2期16卷 143-148页

作者： li Hong-lian WANG Hong-bao HUANG Yi-chen KANG Sha-sha FU Shi-jie li Hao-ran fang li-de li Xiao-ting College of Quality and Technology Supervising Hebei UniversityBaoding 071000China National and Local Joint Engineering Center of Measuring Instruments and Metrology Systems Baoding 071000China College of Chemistry and Environmental Science Hebei UniversityBaoding 071000China College of Optical Sciences University of ArizonaTucson 85721America

When measured by laser induced breakdown spectroscopy, the characteristic parameters of the plasma fluctuate significantly with the experimental parameters, which would have a greater impact on the quantitative measurement. The effects of two experimental parameters, lens to sample distance(LTSD) and delay time, on plasma temperature and electron density were analyzed. Thereafter the optimal LTSD and delay time for quantitative analysis of Pb and Ni in soil were identified. Two element calibration curves were calculated by the internal standard method under the optimal LTSD and delay time. About the two elements, correlation coefficient of the calibration curves is above 0.993. The maximum relative standard deviation(RSD) were 4.47% and 4.76%, respectively, and the maximum relative errors were 12% and 4.8%, respectively. The experimental results showed that laser induced breakdown spectroscopy method in combination with plasma characteristic parameter analysis shows the advantage on quantitative analysis of heavy metals in soil.

关键词： measurement. breakdown analysis

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Double [5]carbohelicene: facile synthesis, chiroptical properties,isomerization study, and lasing application

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Science China Chemistry 2025年第1期68卷 233-240页

作者： Peipei liu Yantong li Meng-Xiang Wu Hao Kang Xiao-li Zhao lin Xu linlin liu Xiaodong li Junfeng fang Zhiwei fang Ya Cheng Hai-Bo Yang Huakang Yu Xueliang Shi State Key Laboratory of Petroleum Molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal University School of Physics and Optoelectronics South China University of Technology Institute of Polymer Optoelectronic Materials & devices State Key Laboratory of Luminescent Materials & Devices South China University of Technology School of Physics and Electronic Science Engineering Research Center of Nanophotonics & Advanced Instrument Ministry of EducationEast China Normal University State Key Laboratory of Precision Spectroscopy School of Physics and Electronic Science East China Normal University

Double carbohelicenes have attracted considerable attention due to their aesthetic structures, distinct π-conjugation extension, inherent chirality, and intriguing optical and electronic properties. Herein, the concise de novo synthesis of a new double[5]carbohelicene 1 together with its chiroptical properties, isomerization process and lasing application is presented. 1 was synthesized by a simple protocol involving the formation of a 6,6′-bipentacene as the key intermediate. It is worth noting that1 existed as two diastereomers 1-PP/MM and 1-PM, which were successfully isolated and unambiguously confirmed by Xray crystallography. The optical resolution of the racemic 1-PP/MM was successfully achieved by chiral-phase highperformance liquid chromatography（HPLC）, and 1-PP and 1-MM were characterized by circular dichroism. Interestingly, it was found that 1-PP/MM could be completely isomerized to 1-PM upon heating, and the detailed thermodynamics and kinetics of the isomerization process were systematically investigated. 1-PM exhibited deep-red luminescence with emission maximum at 723 nm and fluorescence quantum yield as high as 32.95%. Consequently, we can showcase the lasing application of 1-PM by doping with epoxy resin to assemble a bottle microlaser spontaneously, which the lasing wavelength is 796.6 nm at a threshold of 0.8 m J cm-2. We believe that our studies, including the facile synthesis methodology, detailed isomerization studies, and lasing application, will shed some light on the design and synthesis of novel carbohelical systems with more functions.

关键词： double carbohelicene optical resolution organic laser isomerization X-ray diffraction

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deciphering the role of mtH2O2 in hepatic ischemia-reperfusion injury mechanisms with low-background super-resolution fluorogenic probe

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Science China Chemistry 2025年第1期68卷 297-307页

作者： Bin fang limin Wang Haoqin li Jiaxin Zhang Yang Ding Pan Pan li Bo Peng Hua Bai lin li Frontiers Science Center for Flexible Electronics Xi'an Institute of Flexible Electronics (IFE) and Xi'an Institute of Biomedical Materials &Engineering Northwestern Polytechnical University Institute of Flexible Electronics (IFE Future Technologies) Xiamen University

Hepatic ischemia-reperfusion injury（HIRI） is characterized by mitochondrial dysfunction and oxidative stress. Monitoring mitochondrial hydrogen peroxide（mtH2O2） levels in real-time through super-resolution imaging is crucial for elucidating its distribution in live cells and its mechanism of action during HIRI. However, low-background fluorogenic probes have been overlooked in the context of super-resolution imaging. In this study, we developed a low-background fluorogenic probe（MitoWG） with the potential for super-resolution morphology-correlated mitochondrial identification to track the fluctuates of mtH2O2in HIRI. Activation of the desirable fluorescence properties of the probe by mtH2O2was confirmed using structural illumination microscopy（SIM）, enabling high-quality mitochondrial imaging with exceptional specificity and *** in mtH2O2levels were successfully observed in both cellular and rat models of HIRI. Furthermore, we associated the decline in mitochondrial redox homeostasis with accelerated mtH2O2production during HIRI, which triggered mitophagy deficiency and led to cell death. In conclusion, Mito-WG possesses excellent photophysical and low-background properties for SIM imaging, making it a promising tool for mtH2O2tracking in HIRI research and clinical diagnosis.

关键词： hepatic ischemia-reperfusion injury low-background mtH2O2-activatable super-resolution imaging fluorogenic probe

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水平管气液两相流竖直方向压差信号复杂度分析

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热科学与技术 2014年第1期13卷 87-94页

作者：董芳方立德河北大学质量技术监督学院河北保定071002

为了减小沿程摩阻压降的影响,对水平管段气液两相流竖直方向的压差波动信号进行测量,此信号主要由气液两相重位压差和气液两相间作用力产生的压差两部分组成,对其进行分析处理能够得到气液相间作用力对流型变化的影响。对测量信号提取了... 详细信息

为了减小沿程摩阻压降的影响,对水平管段气液两相流竖直方向的压差波动信号进行测量,此信号主要由气液两相重位压差和气液两相间作用力产生的压差两部分组成,对其进行分析处理能够得到气液相间作用力对流型变化的影响。对测量信号提取了Lempel-Ziv复杂性和近似熵两种复杂性测度。结果表明,两种复杂性测度随气相表观速度增加呈增大的趋势,对两相流流型变化是敏感的,能够得到气液两相流动力学结构反演特性。

关键词：气液两相流压差信号 Lempel-Ziv复杂性近似熵相间作用力

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基于狭缝文丘里管的气液两相流测量

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传感技术学报 2008年第8期21卷 1458-1465页

作者：方立德张涛徐英河北大学质量技术监督学院河北保定071002 天津大学电气与自动化工程学院天津市过程检测与控制重点实验室天津300072

提出了一种新的气液两相流测量系统—狭缝文丘里气液两相流测量系统。理论分析表明,狭缝文丘里管利用对称结构可以减小或消除摩阻压降的影响,中间狭缝处垂直于水平流向的重位压降的测量同样避免了沿程摩擦阻力的影响。提出了基于狭缝文... 详细信息

提出了一种新的气液两相流测量系统—狭缝文丘里气液两相流测量系统。理论分析表明,狭缝文丘里管利用对称结构可以减小或消除摩阻压降的影响,中间狭缝处垂直于水平流向的重位压降的测量同样避免了沿程摩擦阻力的影响。提出了基于狭缝文丘里测量系统的气液两相流非分离测量方案,并进行了实验研究。利用狭缝文丘里重位压降信号在三类流动下的特性,可以直接识别流型,在不同的流型下用相应的测量模型求解气液两相的流量。结果表明该方法是可行的。

关键词：气液两相流狭缝文丘里加速压降摩阻压降重位压降

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垂直于水平流向的气液两相流重位压差波动信号分析

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传感技术学报 2008年第7期21卷 1184-1189页

作者：方立德张涛徐英河北大学质量技术监督学院保定071002 天津大学电气与自动化工程学院天津市过程检测与控制重点实验室天津300072

以往对差压波动信号的分析,通常是指平行于流向测得的管道的沿程压力损失或节流装置产生的压力差。本文首次分析了垂直于水平流向的气液两相流重位压差波动信号。根据流体力学基本方程,分析了重位压差与截面含气率的关系,并在天津大学... 详细信息

以往对差压波动信号的分析,通常是指平行于流向测得的管道的沿程压力损失或节流装置产生的压力差。本文首次分析了垂直于水平流向的气液两相流重位压差波动信号。根据流体力学基本方程,分析了重位压差与截面含气率的关系,并在天津大学低压油气水三相流实验装置上进行了实验,讨论了不同流型下重位差压波动信号的功率谱密度特性,重位压差的相对统计方差特性,不同流型下重位压差时均信号的特性,以及重位压差波动信号与时均信号在不同流型的互补特性。

关键词：气液两相流重位压差波动信号截面含气率功率谱密度

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Isobaric enzymatic assays reveal depth-dependent variation in microbial ectoenzyme activities in the deepest ocean on Earth

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Science China Earth Sciences 2025年第1期68卷 185-194页

作者： Junwei CAO Jiahua WANG Hongge ZHANG Junhao deNG Binbin PAN Jiawang CHEN li ZHANG Jiasong fang College of Oceanography and Ecological Science Shanghai Ocean University Ocean College Zhejiang University Laboratory for Marine Biology and Biotechnology Qingdao National Laboratory for Marine Science and Technology

Microbial ectoenzymes play essential roles in the transformation and mineralization of organic matter in the ***, conventional methods for measuring microbial ectoenzyme activities(MEAs) in the deep ocean under atmospheric conditions can misrepresent the metabolic activities of indigenous microbial communities. To overcome this limitation, we measured the activities of three microbial ectoenzymes(aminopeptidase, α-glucosidase, and β-glucosidase) under both atmospheric and in situ pressure conditions in seawater collected using pressure-retaining and non-pressure-retaining samplers in the Challenger deep, Mariana Trench. In the case of aminopeptidase and α-glucosidase, the highest isobaric MEAs were observed in the surface layer(50 m), followed by those at abyssopelagic depths(4,000–6,000 m) for aminopeptidase, hadal realm(10,903 m)for α-glucosidase, while β-glucosidase activity exhibited the highest value at 10,903 m. Furthermore, the isobaric MEAs in hadal waters were commonly found to be higher than the decompressed counterparts, highlighting the importance of pressure-retaining sampling and isobaric enzymatic assays. The half-saturation constant(Km) showed a general decreasing trend with depth,suggesting that the deep ocean microbes might have adapted to the high-pressure and oligotrophic environment by increasing their ectoenzyme's affinity to substrate. Furthermore, particle-free MEAs contribute more to the total MEAs in the deep ocean than particle-associated MEAs, suggesting the significance of cell-associated and dissolved ectoenzymes in ocean *** study provides a foundation for future investigations of MEAs in the ocean and has important implications for understanding the dynamics of microbially mediated biogeochemical cycling in marine ecosystems.

关键词： Pressure-retaining sampling Microbial ectoenzyme activity deep-sea microbes High pressure Mariana Trench

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Al_2O_3包覆正极材料liNi_(1/3)Co_(1/3)Mn_(1/3)O_2

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电池 2016年第6期46卷 306-309页

作者：靳芳芳任丽赵德河北工业大学化工学院天津300130

采用高温固相法制备liNi_（1/3）Co_（1/3）Mn_（1/3）O_2正极材料,并用三氧化二铝（Al_2O_3）进行表面包覆改性。通过XRD、SEM对材料晶体结构、形貌进行分析,用恒流充放电和循环伏安等对材料进行测试。Al_2O_3包覆的liNi_（1/3）Co_（... 详细信息

采用高温固相法制备liNi_（1/3）Co_（1/3）Mn_（1/3）O_2正极材料,并用三氧化二铝（Al_2O_3）进行表面包覆改性。通过XRD、SEM对材料晶体结构、形貌进行分析,用恒流充放电和循环伏安等对材料进行测试。Al_2O_3包覆的liNi_（1/3）Co_（1/3）Mn_（1/3）O_2正极材料具有典型的空间群,为R-3m的六方层状α-Na Fe O2结构。以0.2 C在2.5-4.3 V循环,Al_2O_3包覆量为1%的材料电化学性能最好,首次放电比容量可达145.7 m Ah/g,第30次循环的容量保持率为94.0%,比未包覆Al_2O_3材料在相同条件下的放电比容量提高了6.3%。

关键词：正极材料高温固相法 liNi1/3Co1/3Mn1/3O2 三氧化二铝(Al2O3) 表面包覆

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