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Aerodynamics of Ascending Flight in Fruit Flies

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Journal of Bionic Engineering 2017年第1期14卷 75-87页

作者： xueguang meng Yanpeng Liu mao sun Institute of Fluid Mechanics Beijing University of A eronautics and Astronautics Beijing 100191 China

As a very basic flight mode, ascending flight is obviously of great importance to all kinds of manmade and natural fliers. Yet, for the most commonly seen fliers - insects, researches on this flight mode are rare. In this paper, we combined both experimental measurements and numerical simulations to investigate the kinematical characteristics, aerodynamic performance and power requirement of ascending flight in fruit flies （Drosophila virilis）. The flies ascend at an advance ratio of about 0.12. The most significant characteristic of ascending flight is larger stroke amplitude compared to hovering, while the other kinematics is very similar. From an aerodynamics point of view, this increased stroke amplitude is needed to overcome the negative effects of＂downwash flow＂, caused by the upward motion of the fly. Same as hovering, the ascending fruit flies utilize delayed stall and fast pitching-up mechanisms to generate the majority of the lift required for balancing the weight and body drag. By using a larger stroke-amplitude to overcome the negative effects of＂downwash flow＂, larger energy cost （about 20%） than that of equivalent hovering is required.

关键词： fruit fly ascending flight Computational Fluid Dynamics (CFD) low Reynolds number aerodynamics power requirement

A Metadata Reconstruction Algorithm Based on Heterogeneous Sensor Data for Marine Observations

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Journal of Ocean University of China 2023年第6期22卷 1541-1550页

作者： GUO Shuai sun meng mao Xiaodong College of Science Qingdao University of TechnologyQingdao 266520China College of Information and Control Engineering Qingdao University of TechnologyQingdao 266520China

Vast amounts of heterogeneous data on marine observations have been accumulated due to the rapid development of ocean observation *** state-of-art methods are proposed to manage the emerging Internet of Things(IoT)sensor ***,the use of an inefficient data management strategy during the data storage process can lead to missing metadata;thus,part of the sensor data cannot be indexed and utilized(i.e.,‘data swamp’).Researchers have focused on optimizing storage procedures to prevent such disasters,but few have attempted to restore the missing *** this study,we propose an AI-based algorithm to reconstruct the metadata of heterogeneous marine data in data swamps to solve the above ***,a MapReduce algorithm is proposed to preprocess raw marine data and extract its feature tensors in ***,load the feature tensors are loaded into a machine learning algorithm and clustering operation is *** similarities between the incoming data and the trained clustering results in terms of clustering results are also ***,metadata reconstruction is performed based on existing marine observa-tion data processing *** experiments are designed using existing datasets obtained from ocean observing systems,thus verifying the effectiveness of the *** results demonstrate the excellent performance of our proposed algorithm for the metadata recon-struction of heterogenous marine observation data.

关键词： Internet of Things(IoT) sensor data data swamp metadata reconstruction

Analysis of the Transformation-induced Plasticity Effect during the Dynamic Deformation of High-manganese Steel

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Journal of Materials Science & Technology 2015年第2期31卷 191-198页

作者： Huizhen Wang Xiurong sun Ping Yang Weimin mao Li meng School of Materials Science and Engineering University of Science and Technology Beijing

The transformation-induced plasticity(TRIP) effect and resistance characteristics to adiabatic shear failure at high strain rates of high-manganese steel were investigated by using scanning electron microscopy and electron backscattering diffraction. Results showed that the high-manganese steel exhibited excellent strain hardening effect and resistance to adiabatic shear failure because of the TRIP effect. The TRIP effect occurred during dynamic deformation and showed two distinct stages,namely,the smooth TRIP process before the formation of adiabatic shear band(ASB) and the inhibited TRIP process during further deformation. In the first stage,the martensitic transformation showed slight orientation dependence and weak variant selection,which promoted the TRIP effect. In the second stage,reverse martensitic transformation occurred. Adiabatic shear bands(ASBs) developed typical shear microtextures {111}. In microtextures,two groups of fine grains are in a twin relationship and uniform distribution,which restrained the formation of holes and cracks within the ASBs and enhanced damage resistance after ASB formation.

关键词： High-manganese steel Martensitic transformation Ad

Kinetics process for structure-engineered integrated gradient porous paper-based supercapacitors with boosted electrochemical performance

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Nano Research 2023年第7期16卷 9471-9479页

作者： Chuanyin Xiong Yongkang Zhang Jiayu Xu Weihua Dang Xuhui sun meng An Yonghao Ni Junjie mao College of Bioresources Chemical&Materials Engineering Shaanxi University of Science and TechnologyXi’an 710021China College of Mechanical and Electrical Engineering Shaanxi University of Science and TechnologyXi’an 710021China University of New Brunswick Limerick Pulp&Paper CtrFrederictonNB E3B 5A3Canada College of Chemistry and Materials Science Anhui Normal UniversityWuhu 241000China

Due to their rich and adjustable porous network structure,paper-based functional materials have become a research hotspot in the field of energy ***,reasonably designing and making full use of the rich pore structure of paper-based materials to improve the electrochemical performance of paper-based energy storage devices still faces many ***,we propose a structure engineering technique to develop a conductive integrated gradient porous paper-based(CIGPP)supercapacitor,and the kinetics process for the influence of gradient holes on the electrochemical performance of the CIGPP is investigated through experimental tests and COMSOL *** results indicate that the gradient holes endow the CIGPP with an enhanced electrochemical ***,the CIGPP shows a significant improvement in the specific capacitance,displays rich frequency response characteristics for electrolyte ions,and exhibits a good rate ***,the CIGPP supercapacitor exhibits a low self-discharge and maintains a stable electrochemical performance in different electrolyte environments because of gradient *** importantly,when the CIGPP is used as a substrate to fabricate a CIGPP-PANI hybrid,it still maintains good electrochemical *** addition,the CIGPP supercapacitor also shows excellent stability and sensitivity for monitoring human motion and deaf-mute voicing,showing potential application *** study provides a reference and feasible way for the design of structure-engineered integrated paper-based energy storage devices with outstanding comprehensive electrochemical performance.

关键词： conductive gradient porous paper electrochemical performance COMSOL simulations supercapacitor sensor

Cellular localization of NLRP3 inflammasome

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Protein & Cell 2013年第6期4卷 425-431页

作者： Yan Wang Chen Yang Kairui mao Shuzhen Chen Guangxun meng Bing sun Key Laboratory of Molecular Virology and Immunology Institute Pasteur of ShanghaiShanghai Institutes for Biological SciencesChinese Academy of SciencesShanghai 200025China State Key Laboratory of Cell Biology Institute of Biochemistry and Cell BiologyShanghai Institutes for Biological SciencesChinese Academy of ScienceShanghai 200031China

Infl ammasome is a large protein complex activated upon cellular stress or microbial infection,which triggers maturation of pro-inflammatory cytokines interleukin-1βand interleukin-18 through caspase-1 ***-like receptor family protein 3(NLRP3)is the most character-ized infl ammasome activated by various ***,the mechanism of its activation is unclear and its exact cellular localization is still *** examined the potential co-localization of NLRP3 infl ammasome with mi-tochondria and seven other organelles under adenosine triphosphate,nigericin or monosodium urate stimulation in mouse peritoneal macrophages using confocal micros-copy *** results revealed that the activated endogenous apoptosis-associated speck-like protein containing a CARD(ASC)pyroptosome forms in the cyto-plasm and co-localizes with NLRP3 and caspase-1,but not with any of the organelles *** study indicates that the ASC pyroptosome universally localizes within the cytoplasm rather than with any specifi c organelles.

关键词： NLRP3 inflammasome ASC pyroptosome confocal microscopy cytoplasmic

Construction of hierarchical photocatalysts by growing ZnIn_(2)S_(4) nanosheets on Prussian blue analogue-derived bimetallic sulfides for solar co-production of H_(2) and organic chemicals

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Journal of Energy Chemistry 2021年第3期30卷 386-394页

作者： Liangxuan Zhong Baodong mao meng Liu Mingyue Liu Yaqiu sun Yi-Tao Song Zhi-Ming Zhang Tong-Bu Lu Tianjin Key Laboratory of Structure and Performance for Functional Molecules College of ChemistryTianjin Normal UniversityTianjin 300387China Institute for New Energy Materials&Low Carbon Technologies School of Materials Science&EngineeringTianjin University of TechnologyTianjin 300384China School of Chemistry and Chemical Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

Exploring highly efficient bifunctional photocatalysts for simultaneous H2 evolution and organic chemical production in pure water represents a green route for sustainable solar energy storage and ***,a facile strategy was explored for preparing a hierarchical porous heterostructure of Fe_(4)Ni_(5)S_(8)@ZnIn_(2)S_(4)(FNS@ZIS)by the in situ growth of ZIS nanosheets on Prussian blue analogue(PBA)-derived bimetallic FNS sulfides.A series of FNS@ZIS hierarchical structures were facilely prepared by adjusting the loading amount(n%)of FNS(n=19,26,and 32 for FNS@ZIS-1-3).These structures can efficiently drive the solar co-production of H_(2) and organic *** optimal co-production was achieved with FNS@ZIS-2,affording a H_(2) evolution rate of 10465μmol·g^(-1)·h^(-1),along with high selectivity for the oxidation of benzyl alcohol to benzaldehyde(>99.9%).The performance was 22 and 31 times higher than that of FNS and ZIS,respectively,and even superior to the state-of-the-art results achieved using various sacrificial *** mechanistic study indicated that the unique hierarchical core/shell architecture can facilitate interfacial charge separation,afford bimetallic synergy,abundant active sites and excellent *** work highlights a simple and efficient method for preparing porous multimetallic hierarchical structures for the solar co-production of organic chemicals and H_(2) fuel.

关键词： Prussian blue analogue Photocatalysis Hydrogen evolution Benzyl alcohol oxidation Coordination polymer

Hot working process optimization of Fe-20Mn-19Cr-0.5C-0.6N steel by activation energy, power dissipation and microstructural evolution

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Journal of Iron and Steel Research International 2019年第8期26卷 856-865页

作者： meng-du Peng Jie Shi Wen-chao Yu Bing Cui Ting sun Xiao-yuan Li mao-qiu Wang Institute for Special Steels Central Iron and Steel Research Institute Beijing 100081 China Technology Center Ma'anshan Iron and Steel Co. Ltd. Ma'anshan 243000 Anhui China School of Materials Science and Engineering Anhui University of Technology Ma'anshan 243000 Anhui China

Hot deformation behavior of an Fe-20Mn-19Cr-0.5C-0.6N high-nitrogen austenitic steel has been studied by isothermal compression tests in deformation temperature range of 800-1200℃ and strain rate range of 0.01-10 s^-1. Results indicate that the Fe-20Mn-19Cr-0.5C-0.6N steel has high deformation resistance due to strong hindering effect on dislocation moving by nitrogen-induced lattice misfit. The twinning-induced plasticity effect is gradually suppressed with the increase in deformation temperature, and high-temperature plastic deformation mechanism by twinning is gradually replaced by dislocation planar slip. The deformation resistance is up to 343 MPa at deformation conditions of (1000 ℃, 0.01 s^-1), which is over 100 MPa higher than that in martensitic steel and 50 MPa higher than that in austenitic steel. Besides, value of deformation activation energy for the Fe-20Mn-19Cr-0.6N steel is up to 784 kJ mol^-1. Power dissipation efficiency is lower than 0.13, while hot processing map exhibits a very wide range of working area. The optimum hot working process obtains at deformation temperature range of 950-1200℃ and strain rate range of 0.01-10 s^-1, when deformation acti-vation energy is less than 662.6 kJ mol^-1, power dissipation efficiency exceeds 0.22, dynamic recrystallization fraction is over 46.1% and microstructures are without instable characteristics.

关键词： High-nitrogen austenitic steel Flow behavior Constitutive equation Deformation resistance Deformation activation energy Hot processing map

LAMC1, LAMA2 and LAMA3 gene polymorphisms and the risk for severe pelvic organ prolapse

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Science Bulletin 2019年第7期64卷 466-468页

作者： Lei Li Jia Kang Ye Zhang meng mao Yuxiang Yang Jinghe Lang Zhijing sun Juan Chen Lan Zhu Department of Obstetrics and Gynecology Peking Union Medical College Hospital Chinese Academy of Medical Sciences & Peking Union Medical College

Pelvic organ prolapse (POP) is the descent of the pelvic organs,including bladder, uterus, vagina and rectum, resulting in pelvic discomfort, urinary and fecal incontinence and sexual dysfunction(1)The prevalence of symptomatic POP in China is 9.56%according to a cross-sectional study involving 54,000 adult women in six provinces in the mainland of China (unpublished data). The etiology of this disorder is multifactorial, including race, age, body mass index(BMI), parity and menopause (1)The loss of the integrity of vaginal connective tissue has been demonstrated to weaken the pelvic floor support and promote the development of POP.

关键词： POP LAMA2 and LAMA3 gene polymorphisms and the risk for severe pelvic organ prolapse LAMC1

First wetland mapping at 10-m spatial resolution in South America using multi-source and multi-feature remote sensing data

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Science China Earth Sciences 2024年第10期67卷 3252-3269页

作者： Weiwei sun Gang YANG Yuling HUANG Dehua mao Ke HUANG Lin ZHU Xiangchao meng Tian FENG Chao CHEN Yong GE Department of Geography and Spatial Information Techniques Ningbo UniversityNingbo 315211China State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences&Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Natural Resources and Planning Bureau Shanghai Pudong New DistrictShanghai 200100China Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China Faculty of Electrical Engineering and Computer Science Ningbo UniversityNingbo 315211China School of Geography Science and Geomatics Engineering Suzhou University of Science and TechnologySuzhou 215009China

Wetland degradation has been accelerating in recent years globally. Accurate information on the geographic distribution and categories of wetlands is essential for their conservation and management. Despite being the world′s fourth largest continent, South America has limited research on wetland mapping, and there is currently no available map that provides comprehensive information on wetland distribution and categories in the region. To address this issue, we used Sentinel-1, Sentinel-2 and SRTM data, developed a sample collection method and a wetland mapping method with a collection of multi-source features such as optical features, polarization features and shape features for South American wetlands. We produced a 10-m resolution wetland map based on the Google Earth Engine(GEE) platform. Our Level-1 wetland cover map accurately captured six wetland sub-categories with an overall accuracy of 96.24% and a kappa coefficient of 0.8649, while our Level-2 water cover map included five sub-categories with an overall accuracy of 97.23% and a kappa coefficient of0.9368. The results show that the total area of existing wetlands in South America is approximately 1,737,000 km~2, which is6.8% of the total land area. Among the ten wetland categories, shallow sea had the largest area(960,527.4 km~2), while aquaculture ponds had the smallest area 1513.6 km~2. Swamp had the second largest area(306,240.1 km~2). Brazil, Argentina,Venezuela, Bolivia, and Colombia were found to have the largest wetland areas, with Brazil and Colombia having the most diverse wetland categories. This product can serve as baseline data for subsequent monitoring, management, and conservation of South American wetlands.

关键词： Wetland mapping Google Earth Engine Sentinel imagery South America