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Journal of Sport and Health Science 2024年第2期13卷 204-211页

作者： Kexiang Shi Yunqing Zhu Jun Lv Dianjianyi Sun Pei Pei Huaidong Du Yiping Chen Ling Yang Bing Han Rebecca Stevens Junshi Chen Zhengming Chen liming Li Canqing Yu China Kadoorie Biobank collaborative group Department of Epidemiology&Biostatistics School of Public HealthPeking University Health Science CenterBeijing 100191China Peking University Center for Public Health and Epidemic Preparedness&Response Beijing 100191China Key Laboratory of Epidemiology of Major Diseases(Peking University) Ministry of EducationBeijing 100191China Clinical Trial Service Unit&Epidemiological Studies Unit(CTSU) Nuffield Department of Population HealthUniversity of OxfordOxford OX37LFUK Medical Research Council Population Health Research Unit at the University of Oxford Oxford OX37LFUK NCDs Prevention and Control Department Henan Center for Disease Control and PreventionZhengzhou 450016China China National Center for Food Safety Risk Assessment Beijing 100022China 不详

Background:Information on the association between physical activity(PA)and the risk of chronic kidney disease(CKD)is *** aimed to explore the associations of total,domain-specific,and intensity-specific PA with CKD and its subtypes in ***:The study included 475,376 adults from the China Kadoorie Biobank aged 30-79 years during 2004-2008 at *** interviewer-administered questionnaire was used to collect the information about PA,which was quantified as metabolic equivalent of task hours per day(MET-h/day)and categorized into 4 groups based on *** regression was used to analyze the association between PA and CKD ***:During a median follow-up of 12.1 years,5415 incident CKD cases were documented,including 1159 incident diabetic kidney disease(DKD)cases and 362 incident hypertensive nephropathy(HTN)*** PA was inversely associated with CKD risk,with an adjusted hazard ratio(HR,95%confidence interval(95%CI))of 0.83(0.75-0.92)for incident CKD in the highest quartile of total PA as compared with participants in the lowest *** results were observed for risk of DKD and HTN,and the corresponding HRs(95%CIs)were 0.75(0.58-0.97)for DKD risk and 0.56(0.37-0.85)for HTN *** nonoccupational PA,low-intensity PA,and moderate-to-vigorous-intensity PA were significantly associated with a decreased risk of CKD,with HRs(95%CIs)of 0.80(0.73-0.88),0.85(0.77-0.94),and 0.85(0.76-0.95)in the highest quartile,***:PA,including nonoccupational PA,low-intensity PA,and moderate-to-vigorous-intensity PA,was inversely associated with the risk of CKD,including DKD,HTN,and other CKD,and such associations were dose dependent.

关键词： Chronic kidney disease Domain Intensity Physical activity

Intelligent fault diagnosis methods toward gas turbine: A review

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Chinese Journal of aeronautics 2024年第4期37卷 93-120页

作者： Xiaofeng LIU Yingjie CHEN Liuqi XIONG Jianhua WANG Chenshuang LUO liming ZHANG Kehuan WANG School of Transportation Science and engineering Beihang UniversityBeijing 100191China Systems engineering Research Institute China State Shipbuilding CorporationBeijing 100094China

Fault diagnosis plays a significant role in conducting condition-based maintenance and health management for gas turbines(GTs) to improve reliability and reduce costs. Various diagnosis methods developed by modeling engine systems or certain components implement faults detection and diagnosis based on the measurement of systemic parameters deviations. However, these conventional model-based methods are hindered by limitations of inability to handle the nonlinear nature, measurement uncertainty, fault coupling and other implementing problems. Recently, the development of artificial intelligence algorithms has provided an effective solution to the above problems, triggering broad researches for data-driven fault diagnosis methods with better accuracy,dynamic performance, and universality. This paper presents a systematic review of recently proposed intelligent fault diagnosis methods for GT engines, according to the classification of shallow learning methods, deep learning methods and hybrid intelligent methods. Moreover, the principle of typical algorithms, the evolution of enhanced methods, and the assessment of pros and cons are summarized to conclude the present status and look forward to the future in the field of GT fault diagnosis. Possible directions for development in method validation, information fusion, and interpretability of intelligent diagnosis methods are concluded in the end to provide insightful concepts for scholars in related fields.

关键词： Fault diagnosis Health management Gas turbine Artificial intelligence Intelligent diagnosis method

Effect of trigger system on experimental dispersion characteristics of active surface wave testing

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Earthquake engineering and engineering Vibration 2024年第2期23卷 311-318页

作者： Lin Shibin Jeramy C.Ashlock Zhu liming Qin Zexiang Li Bo Zhu Xingji Zhai Changhai State Key Laboratory of Precision Blasting Jianghan UniversityWuhan 430056China Hubei Key Laboratory of Blasting engineering Jianghan UniversityWuhan 430056China Department of Civil Construction&Environmental EngineeringIowa State UniversityAmesIA 50010USA Wuhan Airport Road Development Co. Ltd.Wuhan 430065China School of Civil and Environmental engineering Harbin Institute of TechnologyShenzhen 518055China Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education Harbin Institute of TechnologyHarbin 150090China Key Lab of Smart Prevention and Mitigation of Civil engineering Disaster of the Ministry of Industry and Information Technology Harbin Institute of TechnologyHarbin 150090China

A trigger system is typically employed in active seismic testing to trigger and synchronize multichannel surface wave data *** effect of the trigger system on the dispersion image of surface waves is empirically known to be negligible,however,theoretical explanation regarding the effect of the trigger system is *** study systematically examines the theory for surface wave dispersion analysis and proves that the effect of the trigger system on a dispersion image is negligible via a solid theoretical ***,based on the new theoretical explanation,an alternative method that uses only the relative phase difference between sensors to extract dispersion characteristics with better conceptual clarity is *** active surface wave testing cases are considered to validate the theory and *** results indicate that(1)an accurate trigger system is not necessary for surface wave data acquisition,and(2)it is unnecessary to assume that the impact point is the generation point of the surface waves for the experimental dispersion analysis.

关键词： site investigation surface waves data acquisition dispersion

A novel nano-grade organosilicon polymer:Improving airtightness of compressed air energy storage in hard rock formations

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International Journal of Mining Science and Technology 2024年第3期34卷 305-321页

作者： Zhuyan Zheng Guibin Wang Chunhe Yang Hongling Ma liming Yin Youqiang Liao Kai Zhao Zhen Zeng Hang Li Yue Han Institute of Rock and Soil Mechanics Chinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Geomechanics and Geotechnical engineering Wuhan 430071China State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400044China PowerChina Huadong engineering corporation Limited Hangzhou 310014China

Enhancing cavern sealing is crucial for improving the efficiency of compressed air energy storage(CAES)in hard rock *** study introduced a novel approach using a nano-grade organosilicon polymer(NOSP)as a sealant,coupled with an air seepage evaluation model that incorporates Knudsen ***,the initial coating application methods were outlined,and the advantages of using NOSP compared to other sealing materials,particularly regarding cost and construction techniques,were also examined and *** results indicated a significant reduction in permeability of rock specimens coated with a 7–10μm thick NOSP ***,under a 0.5 MPa pulse pressure,the permeability decreased to less than 1 n D,and under a 4 MPa pulse pressure,it ranged between4.5×10^(-6)–5.5×10^(-6)m D,marking a 75%–80%decrease in granite *** sealing efficacy of NOSP surpasses concrete and is comparable to rubber *** optimal viscosity for application lies between 95 and 105 KU,and the coating thickness should ideally range from 7 to 10μm,applied to substrates with less than 3%*** study provides new insights into air transport and sealing mechanisms at the pore level,proposing NOSP as a cost-effective and simplified solution for CAES applications.

关键词： Compressed air energy storage Lining Permeability Transient pulse method Hard rock cavern Nano-grade organosilicon polymer coating

Efficient desorption and reuse of collector from the flotation concentrate: A case study of scheelite

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International Journal of Minerals, Metallurgy and Materials 2024年第11期31卷 2435-2444页

作者： Tao, liming Wang, Jianjun Liao, Dejin Jia, Wenkai Zhao, Zihan Che, Wenfang Qi, Zhongxu Sun, Wei Gao, Zhiyong School of Minerals Processing and Bioengineering Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources Engineering Research Center of Ministry of Education for Carbon Emission Reduction in Metal Resource Exploitation and Utilization Central South University Changsha China State Key Laboratory of Mineral Processing BGRIMM Technology Group Beijing China Mining Technology Research Center China Tungsten and Hightech Materials Co. Ltd. Chenzhou China Luoyang Luanchuan molybdenum group Co. Ltd. Luoyang China Changsha Institute of Mining Research Co. Ltd. Changsha China

Flotation is the most common method to obtain concentrate through the selective adsorption of collectors on target minerals to make them hydrophobic and floatable. In the hydrometallurgy of concentrate, collectors adsorbed on concentrate can damage ion-exchange resin and increase the chemical oxygen demand (COD) value of wastewater. In this work, we proposed a new scheme, i.e., desorbing the collectors from concentrate in ore dressing plant and reusing them in flotation flowsheet. Lead nitrate and benzohydroxamic acid (Pb-BHA) complex is a common collector in scheelite flotation. In this study, different physical (stirring or ultrasonic waves) and chemical (strong acid or alkali environment) methods for facilitating the desorption of Pb-BHA collector from scheelite concentrate were explored. Single-mineral desorption tests showed that under the condition of pulp pH 13 and ultrasonic treatment for 15 min, the highest desorption rates of Pb and BHA from the scheelite concentrate were 90.48% and 63.75%, respectively. Run-of-mine ore flotation tests revealed that the reuse of desorbed Pb and BHA reduced the collector dosage by 30% for BHA and 25% for Pb. The strong alkali environment broke the chemical bonds between Pb and BHA. The cavitation effect of ultrasonic waves effectively reduced the interaction intensity between Pb-BHA collector and scheelite surfaces. This method combining ultrasonic waves and strong alkali environment can effectively desorb the collectors from concentrate and provide “clean” scheelite concentrate for metallurgic plants; the reuse of desorbed collector in flotation flowsheet can reduce reagent cost for ore dressing plants.

关键词： scheelite concentrate collector desorption reuse flotation

Design and parameters optimization of the curved sieve for an air suction jujube harvester

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International Journal of Agricultural and Biological engineering 2024年第2期17卷 132-139页

作者： Shenghe Bai Yanwei Yuan Kang Niu liming Zhou Bo Zhao Liguo Wei Lijing Liu Xuejun Zhang College of engineering China Agricultural UniversityBeijing 100083China National Key Laboratory of Agricultural Equipment Technology Chinese Academy of Agricultural Mechanization Sciences Group Co.Ltd.Beijing 100083China College of Mechanical and Electrical engineering Xinjiang Agricultural UniversityUrumqi 830052China

In order to improve the screening performance and cleaning effect of the jujube harvesting machinery cleaning device,a vibrating curved screen device was designed in this *** analyzing the structure mechanism of the curved sieve body,it was obtained that the arc-shaped mesh hole spacing S was 15-25 mm and the curved mesh hole curvature U was 90°-150°.By exploring the movement state and stress of jujube and impurities on the curved sieve body,it was determined that the horizontal spacing L of the curved layer sieve was 30 mm and the vertical spacing H was 45-65 *** the vertical spacing H of the curved layer sieve,the curvature U of the curved mesh hole,and the spacing S of the curved mesh hole as the experimental factors,considering the screening efficiencyαand the impurity contentβof the jujube as the response values,the three-factor three-level quadratic regression orthogonal experiment was designed,establishing the regression mathematical model of each factor and response value,and the multiple target optimization algorithm of Design-expert software was used to optimize various *** results showed that the influence factors on the screening efficiency were in the descending order as:the arc screen spacing,the vertical spacing of the curved layer screen,and the curved screen hole curvature;The significant factors affecting the impurity content of jujube were in the descending order as:the arc screen spacing,the curved screen hole curvature,and the vertical spacing of the curved layer *** experimental results were verified by the optimized combination of parameters:when the vertical spacing H of the curved layer screen was 65 mm,the curved screen hole curvature U was 110°,and the arc screen spacing S was 23 mm,the average screening efficiencyαin the test was 91.09%.The relative error between the experimental verification value and the theoretical optimization value was 1.36%,which was less than 5%.The impurity content of jujubeβin the test w

关键词： jujube harvesting cleaning device curved sieve sieve structure conveying pipe mathematical model

Theory Analysis and Experiment Investigation of Laser Shock Processing on Titanium Alloy Blade

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稀有金属材料与工程 2011年第S4期40卷 235-239页

作者： Che Zhigang1,Gong Shuili1,Cao Ziwen1,Zou Shikun1,Gao Yu2,Ma He1 1Laboratory of Science and Technology on Power Beam Processes,Beijing aeronautical Manufacturing Technology Research Institute,Bei-jing 100024,China 2Shenyang liming aero-engine group corporation Ltd.,Shenyang 110043,China Beijing aeronaut Mfg Technol Res Inst Lab Sci & Technol Power Beam Proc Beijing 100024 Peoples R China Shenyang liming aeroengine Grp Corp Ltd Shenyang 110043 Peoples R China

Laser shock processing (LSP) is an effective surface treatment technology to increase the resistance of metallic components to high-cycle fatigue (HCF),stress corrosion cracking (SCC),wear,etc.,through imparting compressive residual stress on the *** requirement for aeroengine blade treatment and the principle of LSP were introduced at the beginning of this *** key theories and technologies for LSP were analyzed,including improving the pressure model and introducing the technique of eliminating wave reflection at the back of blade during *** nanocrystallation of titanium alloy surface was realized for the first time using the method of laser shocking at the same time no impurity particles were *** treating one kind of aeroengine blade using LSP,the technology parameters were *** nature frequency,fatigue life and residual stress were *** results showed the blade performance was improved obviously,which established the theory and experiment base of laser shock processing on blisk.

关键词： laser shock processing pressure model nanocrystallation natural frequency titanium alloy

Systematic review and Meta-analysis of brain plasticity associated with electroacupuncture in experimental ischemic stroke

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Journal of Traditional Chinese Medicine 2024年第5期44卷 859-870页

作者： XU Yingshan WU Chunxiao YU Wei GUO Hongji LU liming XU Nenggui TANG Chunzhi College of Acupuncture and Massage Shaanxi University of Chinese Medicine Department of Encephalopathy Shenzhen Hospital of Integrated Traditional Chinese and Western MedicineGuangzhou University of Chinese Medicine Department of Obstetrics and Gynecology Shenzhen Hospital of Guangzhou University of Chinese Medicine Medical College of Acu-Moxi and Rehabilitation Guangzhou University of Chinese Medicine

OBJECTIVE: To systematically evaluate the role of electroacupuncture in maintaining brain plasticity in ischemic stroke mediated brain damage. METHODS: We searched for all relevant trials published through Oct 7, 2022 from seven databases. Methodological quality was assessed using the CAMARADES Risk of Bias Tool. A Meta-analysis of comparative effects was performed using Review Manager v.5.3 software. RESULTS: A total of 101 studies involving 2148 animals were included. For most studies, primary outcomes results of the Meta-analysis indicate that EA significantly improved ischemic stroke rat's postsynaptic density thickness [Standardized Mean Difference(SMD) = 1.41, 95% confidence interval(CI)(0.59, 2.23), P = 0.0008], numerical density of synapses [SMD = 1.55, 95% CI(0.48, 2.63), P = 0.005] compared with non-EA-treated. Similarly, EA could improve parts of biomarkers of synapses, neurogenesis, angiogenesis and neurotrophin activity than the control group(P < 0.05). CONCLUSION: The existing evidence suggests EA regulating ischemic stroke may be through brain plasticity. More rigorous and high quality studies should be conducted in the future.

关键词： Meta-analysis animal brain plasticity electroacupuncture experimental ischemic stroke systematic review

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Degradation of EB-PVD thermal barrier coatings caused by CMAS deposits

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Progress in Natural Science:Materials International 2012年第5期22卷 461-467页

作者： Hui Peng a,Lu Wang a,b,Lei Guo a,Wenhui Miao a,Hongbo Guo a,Shengkai Gong a a School of Materials Science and engineering,Beihang University,No.37,Xueyuan Road,Beijing 100191,China b AVIC Shenyang liming aero-engine group corporation Ltd.,Shenyang 110043,China School of Materials Science and engineering Beihang University No.37 Xueyuan Road Beijing 100191 China AVIC Shenyang liming aero-engine group corporation Ltd. Shenyang 110043 China

In aero-turbine engines,thermal barrier coatings(TBCs) must be capable to withstand harsh environments,such as high-temperature oxidation and ***,a new failure mode of TBCs caused by calcium-magnesium-alumina-silicate(CMAS) glass has attracted increasing *** this paper,yttria stabilized zirconia(YSZ) TBCs produced by electron beam physical vapor deposition(EB-PVD) were exposed to CMAS deposits at 1250℃.The microstructure evolution and failure mechanism of the coatings were *** has been shown that CMAS glass penetrated into the YSZ ceramic layer along the inter-columnar gaps and interacted with *** a result,an interaction zone of about 20μm thickness,which was the mixture of CMAS and YSZ with equiaxial structure,was formed in the YSZ surface layer after 4h heat-treatment at 1250℃.Meanwhile,yttria in YSZ layer as a stabilizer was dissolved in CMAS glass and caused accelerated monoclinic phase *** 8h heat-treatment,degradation of YSZ TBC occurred by delamination cracking of YSZ layer,which is quite different from the traditional failure caused by interfacial cracking at the YSZ/metallic bond *** models have been built to describe the failure mechanism of EB-PVD TBCs attacked by CMAS deposits.

关键词： Thermal barrier coatings(TBCs) Electron beam-physical vapor deposition(EBPVD) Calcium-magnesium-alumina-silicate(CMAS) Failure mechanism