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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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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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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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Polypropylene microplastics reshape diazotrophic community composition and interactions in the plastisphere without affecting the rhizosphere of Capsicum annuum L.

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Science of the Total Environment 2025年 978卷 179449页

作者： Liao, Hongkai Ran, Tanshan Zhao, Yuxin Zheng, Chunli Guizhou Provincial Key Laboratory of Mountain Environment Guizhou Normal University Guiyang550001 China The Key Laboratory of Environmental Pollution Monitoring and Disease Control Ministry of Education Department of Toxicology School of Public Health Guizhou Medical University Guizhou Guiyang550025 China

Interactions between microorganisms and microplastics play a crucial role in soil biological processes;however, the response of microbial functional groups in the presence of microplastics (MP) remains unclear. In this study, we investigated the diversity and composition of free-living nitrogen-fixing microorganisms (diazotrophs) in the rhizosphere and plastisphere of pepper (Capsicum annuum L.) across three growth stages under MP stress, using an optimized pipeline for functional nifH gene sequence analysis. Our results showed that MP addition suppressed plant growth, although soil properties were not significantly altered, except for soil pH, which was significantly reduced at each plant growth stage. Notable differences in diazotrophic community composition were observed between the rhizosphere and plastisphere, with the genus Rubrivax exhibiting a significantly lower relative abundance in the plastisphere. Moreover, we found strong deterministic assembly processes and intense network structures of diazotrophs in the plastisphere. Interestingly, MP addition did not significantly alter the diversity, composition, or network properties of diazotrophic communities in the rhizosphere compared to control soils. Our study provides insights into the interactions between microbial functional groups and microplastics, enhancing our understanding of the biological processes that drive ecological nutrient cycling and balance in changing environments. © 2025 Elsevier B.V.

关键词： Anthropogenic

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Fault diagnosis method for blade fracture of gas turbine based on casing vibration

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Mechanical Systems and Signal Processing 2025年 234卷

作者： Hu, Ming-Hui Jin, Bao-teng Liu, Shao-Peng Wang, Wei-Min Jiang, Zhi-Nong Zhang, Xiao-Yang Gao, Jin-ji State Key Laboratory of High-end Compressor and System Technology Beijing University of Chemical Technology Beijing100029 China Key Lab of Engine Health Monitoring-Control and Networking of Ministry of Education Beijing University of Chemical Technology Beijing100029 China Beijing Key Laboratory of Health Monitoring and Self-Recovery for High-End Mechanical Equipment Beijing University of Chemical Technology Beijing100029 China National Key Laboratory of Internal Combustion Engines and Power Systems Weichai Power Co. Ltd. China

Blade fracture is one of the most difficult faults to diagnose in rotating machinery. Most gas turbines can only measure casing vibration rather than directly measuring blade vibration with other sensors, making monitoring and diagnosing such faults more challenging. Research on vibration characteristics and fault diagnosis methods of blade fracture is critical to ensure the safe and reliable operation of gas turbines. The current paper presents a new method to monitor the blade fracture faults from the vibration signal of the casing. Firstly, based on the function mechanism of blade wake excitation forces, the transfer path of the vibration response of gas turbine blades and the variation rule of the wake excitation force have been investigated. Then, based on the casing vibration response model, we analyzed the dynamic evolution of vibration response in the pre- and post-fracture stages of rotor blade failure. The results indicate that the response characteristics of velocity RMS, blade passing frequency (BPF), and fundamental frequency can effectively characterize blade fracture faults. Secondly, based on the vibration-sensitive characteristics of blade fracture faults, we propose an Improved Ordered Cluster Analysis (IOCA) identification method. Considering that the blade fracture can decrease the BPF amplitude and lead to the appearance of side-frequency bands. We propose a Fault Localization Estimation (FLE) method, which constructs a fracture localization factor called ΔUBF, and the highest ΔUBF value corresponds to the stage where the blade fracture has appeared. Finally, A fault diagnosis scheme for gas turbine blade fracture based on casing vibration is proposed. An engineering case of a gas turbine blade fracture fault is analyzed. The results show that the proposed method can timely and effectively diagnose the gas turbine blade fracture fault from the vibration signal of the casing. They can further localize the blade fracture fault at the 8th and 9th s

关键词： Rotating machinery

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Mechanical responses and time-dependent multifractal behaviors of brittle rock under true triaxial stress

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Journal of Rock Mechanics and Geotechnical Engineering 2025年

作者： Hao, Jiawang Fang, Shufan Zhao, Weigang Qiao, Lan Han, Liang Key Laboratory of Structural Health Monitoring and Control School of Safety Engineering and Emergency Management Shijiazhuang Tiedao University Shijiazhuang 050043 China Beijing Key Laboratory of Urban Underground Space Engineering University of Science and Technology Beijing Beijing 100083 China College of Science Wuhan University of Science and Technology Wuhan 430065 China

Unveiling the underlying physical mechanisms governing the fracture of brittle rocks is imperative for preventing rockbursts. The novelty of this study lies in the analysis of the dynamic response process of rock three-dimensional (3D) deformation under true triaxial stress, and the surge behavior of time-dependent multifractal spectrum has been successfully used to warn of progressive failure inside the rock. Firstly, this study analyzed the dynamic adjustment trajectory of rock deformation, specifically lateral strain, within the framework of the Poisson effect. This analysis highlighted the intricate dependence of rock mechanical properties on the intermediate principal stress. Secondly, by defining the crack interval function (ICF), this study compared the disparities between the two crack growth stages (strengthening stage and weakening stage) under varying stress levels. It was found that the fracture activity of granite system has significant multifractal characteristics. Notably, the multifractal spectrum emerges as a valuable tool for characterizing the distinct fracture properties of rocks, encompassing both the crack scale and the associated energy. Finally, a quantitative criterion grounded in the multifractal parameters of the acoustic emission (AE) time series was formulated, and it indicates that the abrupt changes observed in the time-dependent fractal spectra can serve as precursor indicators for the progressive development of rockbursts. © 2025 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences

关键词： AE time series Deformation response Inter-crack function Multifractal theory Rockburst warning True triaxial stress

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