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化学反应工程与工艺 1992年第3期8卷 297-301页

作者：蔡平金涌俞芷青 L.-s.fan 清华大学化工系 100084 美国Ohio state University

以机理实验为依据,提出了一个描述气-固流化床中从鼓泡流态化向湍动流态化流型转变的物理模型。导出了当单位床层体积中气泡数目对气速的二阶导数为零时发生流型转变,该模型的计算机结果与实验数据吻合良好。

关键词：流型流化床反应器

Analysis of Maternal Mortality in Obstetrics and Anesthesia Resuscitation in 15 Years at Chu Point“G”about 389 Cases Bamako/Mali

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Open Journal of Obstetrics and Gynecology 2020年第2期10卷 243-253页

作者： I.Kanté M.sima A.Coulibaly M.Traoré T.Théra A.Bocoum s.Z.Daou A.Kouma s.fané A.Traoré O.Traore Y.Traoré I.Teguété B.Maiga Obstetric Gynecology service of C.H.U Point“G” BamakoMali Obstetric Gynecology service of C.H.U Gabriel TOURE” BamakoMali Common Reference Health Center Commune II BamakoMali Obstetric Gynecology service of C.H.U KATI BamakoMali Obstetrics Gynecology service of CHU Hospital DU Mali BamakoMali Common Reference Health Center Commune V BamakoMali

Objective: Analyze the maternal mortality in the two departments of CHU Point “G” in Bamako, because of high maternal mortality rate in our country. Material and Methods: This was an analytical cross-sectional study on maternal deaths from February 19, 2005 to November 19, 2019 for patients admitted in both departments and who died during the pregnancy-puerperal period at CHU Point “G”. All the patients who died outside this pregnancy-puerperal period were not retained. The data were entered and analyzed using sPss 12.0 software. The statistical test used was that of Chi2, the statistical significance threshold was fixed at 5%. Results: During our study, we recorded 389 maternal deaths out of 16,033 admissions in 15 years and 18,060 live births during the same period making a maternal mortality ratio of 2153.931 and a frequency of 2.426. At the end of our study, we noted that the frequency of maternal deaths was higher in 2014: 12.9% (50/389). The maternal death predominantly affected women aged of 20 - 24 with a frequency of 22.4% (87/389). The multiparity (166/389 making 42.7%), illiteracy (341/389 making 87.7%), the poor evacuation conditions (non-medicalized transport): 263/389 making 67.6%;the evacuation without any evacuation sheet: 259/389 making 66.6%), poor CPN (Prenatal consultation) quality (undone CPN: 191/389 making 49.1%) and the poor monitoring of delivery works (no use of partograph in 343/389 making 88.2%) were the factors favoring maternal deaths. The main causes of maternal deaths were direct in 231/389 making 59.4% with hemorrhage in first line: 21.1% (82/389), infection (61/389 cases making 15.68%), dystocia: 50 cases making 12.85% and high blood pressure and complications (38/389 making 9.76%);indirect in 158/389 cases making 40.6% (Figures 1-3). The majority of women 65.8% (256/389) of our patients died in the gynecology and obstetrics department;in the Resuscitation department 73/389 making 18.8%;in the operating room 43/389 making 11.1% and

关键词： Hemorrhage High Blood Pressure Maternal Death Partographe Prenatal Consultation

Tackling the microlensing wave effects of strong lensing gravitational waves with TAAH

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science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 257-258页

作者： Zuhui fan south-Western Institute for Astronomy Research Yunnan University

The rapid development of gravitational wave（GW） observations since their first detection in 2015 [1] has opened a completely new window for exploring the Universe. Consequently, astronomical research has entered the multimessenger era, allowing us to use different tracers to view the cosmos from various perspectives. Among others, the appealing application of gravitational wave events from compact binary mergers is that they can act as standard sirens to determine absolute cosmic distances entirely independent of standard candles. This approach is one of the most promising means to solve the current H0tension problem.

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soluble epoxide hydrolase:a next-generation drug target for Alzheimer's disease and related dementias

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Neural Regeneration Research 2025年第9期20卷 2585-2586页

作者： Andrew Gregory Chengyun Tang fan fan Department of Physiology Medical College of GeorgiaAugusta UniversityAugustaGAUSA

Alzheimer's disease(AD)and Alzheimer's diseaserelated dementias(ADRD)represent a significant public health challenge,with projections indicating a substantial increase in affected individuals due to the aging global *** the World Health Organization,AD/ADRD has affected more than 55 million individuals worldwide,with an additional 10 million cases diagnosed each year.

关键词： Alzheimer population drug

Reconstructing forest and grassland cover changes in China over the past millennium

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science China Earth sciences 2025年第1期68卷 94-110页

作者： fanneng HE fan YANG Yafei WANG Key Laboratory of Land surface Pattern and simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Key Research Institute of Yellow River Civilization and sustainable Development Henan University University of Chinese Academy of sciences

Historical forest and grassland cover changes not only are critical indicators for quantifying ecological and environmental change processes but also serve as fundamental data for long-term climate change simulations and terrestrial ecosystem carbon emission assessments. However, because of limitations in historical data, quantitative estimations and spatially gridded reconstructions of these changes remain challenging, necessitating further methodological exploration. This study focused on China's present-day land area over the past millennium, objectively capturing the characteristics and drivers of forest and grassland cover changes. On this basis, using the forest transition theory and the space-for-time substitution method, we depicted the historical deforestation process as an inverted “s” curve and developed a model to reconstruct historical forest area changes based on the functional relationship between the forest area and population size dynamics. subsequently, a gridded forest allocation model was established on the basis of deforestation tendencies. For the grassland cover, we implemented regionspecific methods, such as the cropland area deduction method and the habitat constraint method, to quantitatively reconstruct historical changes. Consequently, we obtained provincial forest and grassland area changes over the past millennium and mapped 10-km-resolution gridded data of forest and grassland cover. The results indicated the following.(1) The methods developed using population data as a proxy objectively reproduced the spatiotemporal evolution of forest and grassland cover in China over the past millennium. These feasible methods offer a novel pathway for the quantitative reconstruction of historical forest and grassland cover changes.(2) The data indicated that China's forest area generally decreased over the past millennium, characterized by a “decrease-then-increase” pattern. The forest area experienced three distinct phases: a slow decline(AD 1000

关键词： Land use and land cover change Forest Grassland Quantitative reconstruction Gridded reconstruction China historical period

Dynamic behaviors of graphene platelets-reinforced metal foam piezoelectric beams with velocity feedback control

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 63-80页

作者： Jie CHEN Xinyue ZHANG Mingyang fan school of Mathematics Statistics and Mechanics Beijing University of Technology College of Mechanical & Energy Engineering Beijing University of Technology

Graphene platelets(GPLs)-reinforced metal foam structures enhance the mechanical properties while maintaining the lightweight characteristics of metal foams. Further bonding piezoelectric actuator and sensor layers on the surfaces of GPLs-reinforced metal foam beams enables active vibration control, greatly expanding their applications in the aerospace industry. For the first time, this paper investigates the vibration characteristics and active vibration control of GPLs-reinforced metal foam beams with surfacebonded piezoelectric layers. The constant velocity feedback scheme is used to design the closed-loop controller including piezoelectric actuators and sensors. The effects of the GPLs on the linear and nonlinear free vibrations of the beams are numerically *** Newmark-β method combined with Newton's iteration technique is used to calculate the nonlinear responses of the beams under different load forms including harmonic loads,impact loads, and moving loads. Additionally, special attention is given to the vibration reduction performance of the velocity feedback control on the responses of the beam.

关键词： Piezoelectric actuators

Automatic and Rapid Throughflow-Based Optimal Design Method for Multi-stage Axial-Flow Compressors

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Journal of Thermal science 2025年第1期34卷 77-91页

作者： LEI fan ZHANG Xiawen JU Yaping ZHANG Chuhua Department of Fluid Machinery and Engineering School of Energy and Power EngineeringXi'an Jiaotong University Production and Environmental Department China Huaneng Group.Co.Ltd. state Key Laboratory for strength and Vibration of Mechanical structures Xi'an Jiaotong University

Throughflow design has the advantages of less time consumption and large optimization space,and thus is the corner stone of advanced design system of multi-stage axial-flow *** majority of relevant studies were limited to the throughflow inverse designs,and quite few works have been till now devoted to the throughflow optimal *** this work,an automatic and rapid throughflow-based optimal design method is proposed for axial-flow compressors in which a throughflow inverse design solver is embedded in optimal genetic algorithm to improve the design efficiency of axial-flow *** types of design parameters in the throughflow inverse design of axial-flow compressors,i.e.,swirl and shroud curve,are simultaneously used to optimize both the blade shape and flow *** proposed method is validated by the redesign optimization of the benchmark axial-flow compressor NAsA stage 35,and the CFD predictions show that the throughflow-based optimization leads to 1.18% efficiency benefit at design *** proposed method is then utilized to the two-dimensional throughflow optimal design of a large-scale 6.5-stage axial-flow industrial *** optimal design results are confirmed by CFD predictions,indicating that the proposed method can effectively improve the design adiabatic efficiency of the compressors by 1.09% within a few minutes on desk-top *** throughflow design implications are also obtained for advanced axial-flow industrial *** work could enhance the capability of throughflow design method and has engineering application value to explore the throughflow optimization space of multi-stage axial-flow compressors.

关键词： NAsA

Effect of a Carbon Fibre-steel Fibre-graphite Conductive Filler on the Electrothermal Properties of Cementitious Materials

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Journal of Wuhan University of Technology(Materials science) 2025年第1期40卷 141-151页

作者： fan Yanan WEI Hong ZHENG Hongyong DU Hongxiu Department of Architecture and Environmental Engineering Taiyuan UniversityTaiyuan 030032China College of Civil Engineering Taiyuan University of TechnologyTaiyuan 030032China

Carbon fibre,steel fibre and graphite were used as conductive fillers to prepare cementitious materials with excellent electrothermal *** electrically conductive cementitious materials with different volume dosages were analysed through compressive and flexural strength,electrochemical impedance spectroscopy and temperature rise *** equivalent circuit model was established to study the electrically conductive heat generation mechanism in the electrically conductive cementitious *** results indicate that the mechanical properties of cementitious composite materials with a ternary conductive phase are better than those of pristine cementitious materials because the fibrous filler improves their mechanical ***,the incorporation of graphite in the material reduces its *** fibrous and point-like conductive phase materials into the cementitious material enhances the overall conductive pathway and considerably reduces the electrical resistance of the cementitious material,enhancing its conductive *** volume ratios of carbon fibre,steel fibre and graphite that achieve an optimal complex doping in the cementitious material were 0.35%,0.6%and 6%,*** was determined using the mutation point of each circuit element parameter as the percolation *** addition,at a certain safety voltage,there is a uniform change between the internal and surface temperatures of the conductive cementitious material,and the heating effect in this materialis is considerably better than that in the pristine cementitious material.

关键词： cementitious composites conductive fillers electrothermal properties electrochemical impedance spectroscopy

Endoscopy-assisted lightweight diagnosis system based on transformers for colon polyp detection

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Optoelectronics Letters 2025年第1期21卷 57-64页

作者： fan Weiming YU Jiahui JU Zhaojie school of Automation and Electrical Engineering Shenyang Ligong University Department of Biomedical Engineering Zhejiang University school of Computing University of Portsmouth

The integration of endoscopy has significantly propelled the diagnosis and treatment of gastrointestinal diseases, with colonoscopy establishing itself as the primary method for early diagnosis and preventive care in colorectal cancer(CRC). Although deep learning holds promise in mitigating missed polyp rates, modern endoscopy examinations pose additional challenges, such as image blurring and atomizing. This study explores lightweight yet powerful attention mechanisms, introducing the spatial-channel transformer(sCT), an innovative approach that leverages spatial channel relationships for attention weight calculation. The method utilizes rotation operations for inter-dimensional dependencies, followed by residual transformation, encoding inter-channel and spatial information with minimal computational overhead. Extensive experiments on the CVC-Clinic DB polyp detection dataset, addressing endoscopy pitfalls, underscore the superiority of our sCT over other state-of-the-art methods. The proposed model maintains high performance, even in challenging scenarios.

关键词： Endoscopy

Effects of carbon content on the microstructure and tensile properties of a low-density steel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 391-401页

作者： Yongxuan shang Mingyu fan shuyong Jiang Zhongwu Zhang Key Laboratory of superlight Materials and surface Technology Ministry of EducationCollege of Materials Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001China state Key Laboratory of Metal Material for Marine Equipment and Application Iron&Steel Research Institute of Ansteel Group CorporationAnshan 114009China

Carbon can change the phase components of low-density steels and influence the mechanical *** this study,a new method to control the carbon content and avoid the formation ofδ-ferrite by decarburization treatment was *** microstructural changes and mechanical characteristics with carbon content induced by decarburization were systematically ***-Jaoul(C-J)analysis was employed to examine the work hardening characteristics during the tensile *** decarburization by heat treatments,the carbon content within the austenite phase decreased,while Mn and Al were almost unchanged;this made the steel with full austenite transform into the austenite and ferrite dual ***,(Ti,V)C carbides existed in both matrix phase and the mole fraction almost the *** addition,the formation of other carbides *** loss induced a decrease in strength due to the weakening of the carbon solid *** the steel with the single austinite,the deformation mode of austenite was the dislocation planar glide,resulting in the formation of *** the dual-phase steel,the deformation occurred by the dislocation planar glide of austenite first,with the increase in strain,the cross slip of ferrite took place,forming dislocation cells in *** the late stage of deformation,the work hardening of austinite increased rapidly,while that of ferrite increased slightly.

关键词： low-density steels carbon content decarburization strengthening mechanisms work hardening behavior