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A novel rotor dynamic balancing method based on blade tip clearance measurement without the once per revolution sensor

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Chinese Journal of Aeronautics 2025年第2期38卷 445-458页

作者： Weibo LI Weimin WANG Shuai ZHANG Jiale WANG Yulong LIN Tianqing LI Key Lab of Engine Health Monitoring-Control and Networking of Ministry of Education Beijing University of Chemical TechnologyBeijing 100029China State Key Laboratory of High-end Compressor and System Technology Beijing University of Chemical TechnologyBeijing 100029China

The existence of the aeroengine casing,limited monitoring points,and multi-fault characteristics make obtaining the rotor’s vibration transmission characteristics challenging,resulting in difficulties accurately identifying the rotor *** paper utilizes a high-frequency composite sensor to monitor the engine’s blade tip clearance(BTC)and extracts unbalanced information from BTC signals for rotor dynamic balancing,while avoiding the need for the once per revolution(OPR)***,the vibration characteristics of the rotor-blade system under multi-fault conditions are ***,based on BTC measurement,a none OPR method and an unbalance identification method are proposed,in which the radial vibration of the blade tip in the BTC signals at different speeds is extracted and operated in the time domain to obtain the rotor unbalanced vibration,the signal is reconstructed,and cross-correlation analysis is used to accurately identify the magnitude and phase of the unbalanced ***,a rotor test bench is utilized for experimental *** results reveal that the dynamic balancing method based on the BTC signal can more precisely identify the rotor unbalance than the traditional rotor dynamic balancing *** application of this technique will effectively improve engine health management and fault prediction.

关键词： Aeroengine Rotor unbalance Composite sensor None once per revolution Blade tip clearance Dynamic balancing

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Enhanced VOC emission with increased temperature contributes to the shift of O_(3)-precursors relationship and optimal control strategy

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Journal of Environmental Sciences 2025年第4期150卷 218-229页

作者： Fangqi Qu Yuanjie Huang Yemin Shen Genqiang Zhong Yan Xu Lingling Jin Hongtao Qian Chun Xiong Fei Zhang Jiasi Shen Bingye Xu Xudong Tian Zhengning Xu Zhibin Wang Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control MOE Key Laboratory of Environment Remediation and Ecological HealthCollege of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China ZJU-Hangzhou Global Scientific and Technological Innovation Center Zhejiang UniversityHangzhou 311215China Jiaxing Ecological and Environment Bureau Tongxiang Branch Tongxiang 314500China Zhejiang Ecological and Environmental Monitoring Center Hangzhou 310012China Zhejiang Key Laboratory of Ecological and Environmental Monitoring Forewarning and Quality ControlHangzhou 310058China

Assessing the impact of anthropogenic volatile organic compounds(VOCs)on ozone(O_(3))formation is vital for themanagement of emission reduction and pollution *** of O_(3)and the major precursorswas conducted in a typical light industrial city in the YRD region from 1 May to 25 July in *** were the most abundant VOC group,contributing to 55.0%of TVOCs concentration(56.43±21.10 ppb).OVOCs,aromatics,halides,alkenes,and alkynes contributed 18.7%,9.6%,9.3%,5.2%and 1.9%,*** observational site shifted from a typical VOC control regime to a mixed regime from May to July,which can be explained by the significant increase of RO_(x)production,resulting in the transition of environment from NOx saturation to radical saturation with respect to O_(3)*** optimal O_(3)control strategy should be dynamically changed depending on the transition of control *** NOx saturation condition,minimizing the proportion of NOx in reduction could lead to better achievement of O_(3)*** mixed control regime,the cut percentage gets the top priority for the effectiveness of O_(3)*** VOCs sources were identified:temperature dependent source(28.1%),vehicular exhausts(19.9%),petrochemical industries(7.2%),solvent&gasoline usage(32.3%)and manufacturing industries(12.6%).The increase of temperature and radiation would enhance the evaporation related VOC emissions,resulting in the increase of VOC concentration and the change of RO_(x)*** results highlight determination of the optimal control strategies for O_(3)pollution in a typical YRD industrial city.

关键词： O_(3)pollution Volatile organic compounds Photochemical box model Source apportionment Optimal O_(3)control strategies

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Compensation method and sensitivity analysis of DPHP frozen soil ice content measurement

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Research in Cold and Arid Regions 2025年第2期17卷 85-96页

作者： Cai, YongMing Wang, Meng Li, Xu Chen, WenHua Candidate Key Laboratory of Urban Underground Engineering of Ministry of Education Beijing Jiaotong University Beijing 100044 China Key Laboratory of Structural Health Monitoring and Control Shijiazhuang Tiedao University Hebei Shijiazhuang 050043 China School of Civil Engineering Beijing Jiaotong University Beijing 100044 China

The Duel-Probe-Heat-Pulse (DPHP) ice content sensor can measure the ice content of the soil, but its measurement process is not clear for the disturbance of frozen soil. In this study, the ice content measurement test was carried out for silty clay specimens. Firstly, the influence of heating power was clarified. The variation trends of the temperature rise relaxation area in the respective conditions of the three representative volumetric water content specimens and the degree of compaction of the specimen preparation was compared. Then, the influence of five kinds of heating interval time on the measurement accuracy was explored. Finally, the compensation and analysis method of the temperature relaxation area, based on the temperature of the measuring point and the phase change of ice water, is proposed. The experimental results show that: (1) There is a hysteresis in the temperature rise curve of the probe of the DPHP ice content sensor. In the measurement process, a long enough integral interval should be selected to calculate the temperature relaxation area. (2) For the specimens with the same initial water content, the measured temperature relaxation area increases with the increase of compaction degree, and this trend weakens in the specimens with the increase of water content. (3) The DPHP ice content sensor causes irreversible disturbance to the soil during the measurement process. The temperature relaxation area, obtained by continuous measurement at a short heating interval, is small, and manifests a decreasing trend with the increase of measurement times. (4) It is recommended that the heating interval time should be more than 120 min, and the temperature relaxation area should be compensated when the continuous measurement of short heating interval time is carried out, to offset the influence of the temperature rise of the measuring point. The research results reveals the influence of multiple factors on the measurement of DPHP ice content sensors, whic

关键词： Duel-probe-heat-pulse method Soil ice content Temperature modeling compensation Temperature relaxation area Thermal conductivity

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Construction of core-triple shell upconversion nanostructures NaNdF4:Yb,Gd@NaGdF4:Yb@NaGdF4:Yb,Er@NaGdF4 with high FRET efficiency for the biochemical sensor

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Ceramics International 2025年第12期51卷 16986-16995页

作者： Liao, Chuan Wang, Jiaxuan Liu, Hanqing Xu, Jing Zhou, Wen Guo, Peng Wang, Tao Zhou, Guangjun Hu, Jifan State Key Laboratory of Crystal Materials Shandong University Jinan250100 China Health Inspection and Testing Institute Shandong Provincial Center for Disease Control and Prevention Jinan250014 China Shandong Provincial Key Laboratory of Marine Monitoring Instrument Equipment Technology National Engineering and Technological Research Center of Marine Monitoring Equipment Qingdao266061 China

Upconversion nanoparticles (UCNPs) are excellent energy donors for Föster resonance energy transfer (FRET) systems. However, the lower FRET efficiency to some extend limits its application. To improve the efficiency of FRET, NaNdF4:Yb,Gd@NaGdF4:Yb@NaGdF4:Yb,Er@NaGdF4 core-triple shell (CTS) UCNPs with sensitizers in the core region and activators doped in the outer shell region were successfully prepared by changing the traditional core-shell structure design sequence. By introducing a certain amount of Gd3+ into the core nanoparticles, the crystal growth process of core nanoparticles was regulated, solving the problem of excessive and uneven size caused by high concentration of sensitizers. The insertion of Yb3+ doped transition layer weakens the negative effect between Nd3+ and activator ions, and enhances the luminescence intensity. In addition, comparing CTS UCNPs with UCNPs prepared in the traditional core-shell structure design sequence proves that CTS UCNPs have higher FRET efficiency. A biochemical sensing system was designed using this novel core-shell structure UCNPs, achieving simultaneous detection of GSH and Cd2+ with detection limits of 4.2 nM and 15.2 nM, respectively. The new core-shell structure UCNPs have broader application prospects in the field of biochemical sensing design. © 2024 Elsevier Ltd and Techna Group S.r.l.

关键词： Shells (structures)

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A comparative study on the formation of nitrogen-containing organic compounds in cloud droplets and aerosol particles

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Journal of Environmental Sciences 2025年第3期149卷 456-464页

作者： Guohua Zhang TaoWang Qinhao Lin Kun Liu Wei Sun Duohong Chen Lei Li Xinming Wang Xinhui Bi State Key Laboratory of Organic Geochemistry and Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization Guangzhou Institute of GeochemistryChinese Academy of Sciences(CAS)Guangzhou 510640China Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control Guangzhou Institute of GeochemistryCASGuangzhou 510640China University of Chinese Academy of Sciences Beijing 100049China School of Environmental Science and Engineering Institute of Environmental Health and Pollution ControlGuangdong University of TechnologyGuangzhou 510006China State Environmental Protection Key Laboratory of Regional Air Quality Monitoring Guangdong Environmental Monitoring CenterGuangzhou 510308China Institute of Mass Spectrometer and Atmospheric Environment Jinan UniversityGuangzhou 510632China

Nitrogen-containing organic compounds(NOCs)may potentially contribute to aqueous secondary organic aerosols,yet the different formation of NOCs in aerosol particles and cloud droplets remains *** the in-situ measurements performed at a mountain site(1690 m a.s.l.)in southern China,we investigated the formation of NOCs in the cloud droplets and the cloud-free particles,based on their mixing state information of NOCscontaining particles by single particle mass *** relative abundance of NOCs in the cloud-free particles was significantly higher than those in cloud residual(cloud RES)*** were highly correlated with carbonyl compounds(including glyoxalate and methylglyoxal)in the cloud-free particles,however,limited correlation was observed for cloud RES *** of their mixing state and temporal variations highlights that NOCs was mainly formed from the carbonyl compounds and ammonium in the cloud-free particles,rather than in the cloud RES *** results support that the formation of NOCs from carbonyl compounds is facilitated in concentrated solutions in wet aerosols,rather than cloud *** addition,we have identified the transport of biomass burning particles that facilitate the formation of NOCs,and that the observed NOCs is most likely contributed to the light *** findings have implications for the evaluation of NOCs formation and their contribution to light absorption.

关键词： Nitrogen-containing organic compounds Individual particles Cloud Carbonyl compounds Mixing state

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Research on the life prediction of vehicle engine cylinder head driven by dual channel Markov chain

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High Technology Letters 2025年第1期31卷 12-19页

作者： LI Zhijie WANG Yonglai CHEN Cuicui ZHOU Long WANG Yao YUAN Shaoshe National Key Laboratory of Internal Combustion Engines and Power Systems Weichai Power Co.Ltd.Weifang 261061P.R.China Key Laboratory of Engine Health Monitoring-control and Networking Ministry of EducationBeijing University of Chemical TechnologyBeijing 100029P.R.China

The performance degradation of vehicle engine cylinder heads is a complex phenomenon,and the accurate prediction of their remaining useful life is essential for maintenance *** address the problem of low prediction accuracy caused by insufficient data mining depth in current prediction models for the remaining service life of engine cylinder heads,a prediction method of dualchannel model is ***,the driving status data of multiple vehicles is summarized and analyzed,and the on-board network common variables related to cylinder head life are ***,driving segments are defined,the driving state features of each driving segment are extracted,and feature correlation analysis and principal component analysis are *** driving state profiles of the vehicle are divided using the clustering algorithm,and the cumulative degradation factors for driving state profiles are defined and ***,the mileage of each driving segment is classified into intervals by applying fuzzy set theory,and the state transfer probability matrices of driving state profiles and driving segment mileage are calculated.A new engine head life prediction model based on dual channel Markov chain(DCMC)is ***,the proposed method is applied to the residual life prediction of cylinder head of seven actual vehicles,and the comparison with actual life statistics results proved the validity of the proposed method.

关键词： engine cylinder head driving cycle vehicle networking life prediction

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Coumarin Glycosides Reverse Enterococci-Facilitated Enteric Infections

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Research 2025年第1期2024卷 121-134页

作者： Wenjiao Xu Guixin Yuan Yuwen Fang Xiaojia Liu Xiaowei Ma Kui Zhu National Key Laboratory of Veterinary Public Health and Safety College of Veterinary MedicineChina Agricultural UniversityBeijing 100193China Engineering Research Center of Animal Innovative Drugs and Safety Evaluation Ministry of EducationCollege of Veterinary MedicineChina Agricultural UniversityBeijing 100193China Ministry of Agriculture and Rural Affairs Key Laboratory for Crop Pest Monitoring and Green Control China Agricultural UniversityBeijing 100193China

Commensal enterococci with pathogenic potential often facilitate the growth of diverse pathogens,thereby exacerbating ***,there are few effective therapeutic strategies to prevent and intervene in enterococci-mediated polymicrobial ***,we find that enterococci at high density drive the expansion and pathogenicity of enteric Salmonella enterica serotype Typhimurium(***).Subsequently,we show that the driving role of enterococci in such infections is counteracted by dietary coumarin glycosides in ***,which are tolerant of iron-deficient environments,produceβ-glucosidases to hydrolyze coumarin glycosides into bioactive aglycones,inhibiting *** growth and ameliorating the severity of ***-induced symptoms by inducing iron ***,we demonstrate that coumarin glycosides as a common diet effectively reverse enterococci-facilitated enteric infections,providing an alternative intervention to combat polymicrobial infections.

关键词： polymicrobial infections coumarin glycosides dietary coumarin g iron limitation enterococci enteric infections commensal enterococci glucosidases

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Smart monitoring of the expansion state of boiler water walls in coal-fired power plants using a digital twin model

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Proceedings of the Estonian Academy of Sciences 2025年第2期74卷 149-154页

作者： Luo, Lijia Wang, Weida Lei, Zhenheng Bao, Shiyi Bassir, David Chen, Gongfa College of Mechanical Engineering Zhejiang University of Technology China Zhejiang Rancon Turbine Machinery Co. Ltd. China Smart Structural Health Monitoring and Control Laboratory Sino-French Institute Dongguan University of Technology China IRAMAT UMR-CNRS 7065 UTBM CEDEX Belfort France

This article presents an approach for monitoring the expansion state of water walls in coal-fired power plants using a digital twin (DT) model. The monitored boiler belongs to a 1000 MW ultrasupercritical power generating unit;it has been in service for more than 14 years and has accumulated more than 100 000 hours of operation. The fracture of the water wall has become a serious problem for safe operation. The size of the water wall is huge, the structure is complex, the stress state is changeable, and the fracture treatment is difficult. Existing online monitoring systems are mainly based on wall temperature, and it is difficult to evaluate the stress state of the water wall. However, there are few technical systems that can monitor the expansion displacement and local strain/stress of water walls online. To address this problem, a DT model is built to monitor the expansion state of boiler water walls. An optical non-contact strain monitoring system (based on digital image correlation (DIC) technologies) coupled with finite element analysis is developed to measure the actual strain/stress data and generate more simulation data for improving the accuracy of the DT model. This monitoring system provides an effective way to prevent the expansion fracture of the water wall. © 2025 Authors.

关键词： Fossil fuel power plants

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Effect of Coix Seed on the Rheological and structural Properties of Wheat Dough and Noodle Quality

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食品科学 2025年第11期46卷 64-75页

作者： WU Yingmei XU Longquan YU Yunliu LUO Guangjie WANG Chengli PU Dingfang HUANG Qun Key Laboratory of Environmental Pollution Monitoring and Disease Control Ministry of EducationGuizhou Provincial Engineering Research Center of Ecological Food InnovationSchool of Public HealthGuizhou Medical UniversityGuiyang 561113China Technology Center of China Tobacco Guizhou Industrial Co.Ltd. Guiyang 550000China

The effect of coix seed flour(0%–25%)on the rheological and structural properties of wheat dough and noodle quality was *** addition of coix seed flour was found to enhance the elasticity of dough,which may be attributed to the fact that small starch particles increase the filling capacity within the dough *** increase subsequently resulted in more complete and uniform structure of ***,setback viscosity rose to 1095 *** rapid water absorption of coix seed starch led to changes in the secondary structure of proteins in *** proportion ofβ-sheet markedly increased,whereas the proportion ofα-helix decreased with increasing level of coix seed flour ***,coix seed flour substitution significantly reduced the estimated glycemic index of *** analysis revealed that pasting parameters had significant effects on the evaluation of noodle *** study provides a foundation for researchers to substitute wheat flour with coix seed flour.

关键词： coix seed dough properties noodle quality

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Gaseous air pollution exposure and depression in middle-aged and elderly adults: evidence from a Chinese cohort

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Environmental Science: Processes and Impacts 2025年第5期27卷 1472-1481页

作者： Zhou, Yumeng Wang, Kexue Wang, Xiaoqing Tang, Enjie Liu, Hao Liu, Xiaoling Yao, Chunyan Wang, Liangmei Zhou, Chunbei Li, Qianqian Xu, Wuwei Lu, Wuqiang Ji, Ailing Cai, Tongjian Department of Disease Prevention and Control Daping Hospital State Key Laboratory of Trauma and Chemical Poisoning Army Medical University Third Military Medical University Chongqing400042 China Department of Physico-chemical Inspection Shijiazhuang Center for Disease Control and Prevention Shijiazhuang050011 China Department of Neurology 925 Hospital of PLA Joint Logistics Support Force Guiyang550009 China Department of Epidemiology College of Preventive Medicine State Key Laboratory of Trauma and Chemical Poisoning Army Medical University Third Military Medical University Chongqing400038 China School of Public Health The Key Laboratory of Environmental Pollution Monitoring and Disease Control Ministry of Education Guizhou Medical University Guiyang550025 China Chongqing Center for Disease Control and Prevention Chongqing400700 China Department of Digital Health Chongqing College of Architecture and Technology Chongqing401331 China

Increasing research has investigated the impact of atmospheric gaseous air pollution on depression. However, the results have exhibited inconsistencies, and the majority of studies have focused on the impact of long- or short-term exposures. The aim of the study was to investigate the impact of intermediate-term exposure to gaseous air pollution on depression in middle-aged and older adults. In 2013, 8639 participants aged 45 and above were enrolled in the China health and Retirement Longitudinal Study (CHARLS). Using a linear mixed-effects model, we examined the association between gaseous air pollution (NO2, SO2, CO, and O3) and depression over intermediate-term exposure windows (30, 60, 90, and 180 days). Interaction and subgroup analyses were conducted to identify potential effect modifiers in the association. Every 10 μg m−3 increase in NO2 and SO2 was associated with increased depression scores, with the most pronounced effects observed in the 30 day exposure window (β = 0.55, 95% CI: 0.25-0.85) and 60 day exposure window (β = 0.75, 95% CI: 0.52-0.99), respectively. For CO, every 1 mg m−3 increase was associated with elevated depression scores in the 60 day exposure window (β = 1.28, 95% CI: 0.44-2.13). Interaction analyses revealed that individuals who consumed alcohol, lived in urban areas, or were married exhibited heightened susceptibility to the effects of gaseous air pollution on depression. Here, we provide the first evidence that intermediate-term gaseous air pollution exposure within specific temporal windows may substantially increase the risk of depression. It is important to prioritize individuals who consume alcohol, live in urban areas, and are married. © 2025 The Royal Society of Chemistry.

关键词： Air quality

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