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Design and optimization of fluid lubricated bearings operated with extreme working performances——a comprehensive review

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International Journal of Extreme Manufacturing 2024年第2期6卷 325-376页

作者： Guohua Zhang Ming Huang Gangli Chen Jiasheng Li Yang Liu Jianguo He Yueqing Zheng Siwei tang hailong Cui Institute of Machinery Manufacturing Technology China Academy of Engineering PhysicsMianyangSichuan 621999People’s Republic of China

Fluid lubricated bearings have been widely adopted as support components for high-end equipment in metrology,semiconductor devices,aviation,strategic defense,ultraprecision manufacturing,medical treatment,and power generation.In all these applications,the equipment must deliver extreme working performances such as ultraprecise movement,ultrahigh rotation speed,ultraheavy bearing loads,ultrahigh environmental temperatures,strong radiation resistance,and high vacuum operation,which have challenged the design and optimization of reliable fluid lubricated bearings.Breakthrough of any related bottlenecks will promote the development course of high-end equipment.To promote the advancement of high-end equipment,this paper reviews the design and optimization of fluid lubricated bearings operated at typical extreme working performances,targeting the realization of extreme working performances,current challenges and solutions,underlying deficiencies,and promising developmental directions.This paper can guide the selection of suitable fluid lubricated bearings and optimize their structures to meet their required working performances.

关键词： fluid lubricated bearings structural design performance optimization extreme working performances

A multi-fidelity simulation method research on front variable area bypass injector of an adaptive cycle engine

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Chinese Journal of Aeronautics 2022年第4期35卷 202-219页

作者： Zhewen XU Ming LI hailong tang Min CHEN School of Energy and Power Engineering Beihang UniversityBeijing 100083China Aero Engine Academy of China Beijing 101300China Research Institute of Aero-Engine Beihang UniversityBeijing 102206China

Front Variable Area Bypass Injector(Front-VABI) is a component of the Adaptive Cycle Engine(ACE) with important variable-cycle features. The performance of Front-VABI has a direct impact on the performance and stability of ACE, but the current ACE performance model uses approximate models for Front-VABI performance calculation. In this work, a multi-fidelity simulation based on a de-coupled method is developed which delivers a more accurate calculation of the Front-VABI performance based on Computational Fluid Dynamics(CFD) simulation. This simulation method proposes a form of Front-VABI characteristic and its matching calculation method between it and the ACE performance model, constructs a coupling method between the(2-D) Front-VABI model and the(0-D) ACE performance model. The result shows, when ACE works in triple bypass mode, the approximate model cannot account for the effect of FrontVABI pressure loss on Core Driven Fan Stage(CDFS) design pressure ratio, and the calculated error of high-pressure turbine inlet total temperature is more than 40 K in mode transition condition(the transition operating condition between triple bypass mode and double bypass mode). In double bypass mode, the approximate model can better simulate the performance of FrontVABI by considering the local loss of area expansion. This method can be applied to the performance-optimized design of Front-VABI and the ACE control law design during mode transition.

关键词： Adaptive cycle engine Computational fluid dynamics Front variable area bypass injector Multi-fidelity simulation Performance model

Plant genomic resources at National Genomics Data Center:assisting in data-driven breeding applications

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aBIOTECH 2024年第1期5卷 94-106页

作者： Dongmei Tian Tianyi Xu hailong Kang Hong Luo Yanqing Wang Meili Chen Rujiao Li Lina Ma Zhonghuang Wang Lili Hao Bixia tang Dong Zou Jingfa Xiao Wenming Zhao Yiming Bao Zhang Zhang Shuhui Song National Genomics Data Center Beijing Institute of GenomicsChinese Academy of Sciences&China National Center for BioinformationBeijing 100101China CAS Key Laboratory of Genome Sciences and Information Beijing Institute of GenomicsChinese Academy of Sciences&China National Center for BioinformationBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Genomic data serve as an invaluable resource for unraveling the intricacies of the higher plant systems,including the constituent elements within and among species.Through various efforts in genomic data archiving,integrative analysis and value-added curation,the National Genomics Data Center(NGDC),which is a part of the China National Center for Bioinformation(CNCB),has successfully established and currently maintains a vast amount of database resources.This dedicated initiative of the NGDC facilitates a data-rich ecosystem that greatly strengthens and supports genomic research efforts.Here,we present a comprehensive overview of central repositories dedicated to archiving,presenting,and sharing plant omics data,introduce knowledgebases focused on variants or gene-based functional insights,highlight species-specific multiple omics database resources,and briefly review the online application tools.We intend that this review can be used as a guide map for plant researchers wishing to select effective data resources from the NGDC for their specific areas of study.

关键词： Plant-omics data Data repositories Data integration Knowledgebase Plant genomics

Spatiotemporal distribution, environmental risk and carbon emission reduction potential of livestock manure in Shaanxi Province, China

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Frontiers of Agricultural Science and Engineering 2024年第3期11卷 381-396页

作者： Mengyuan QIAO Jianchun ZHU Ronghua LI Junting PAN Ran XIAO hailong WANG Kuok Ho Daniel tang Zengqiang ZHANG College of Humanities & Social Development Northwest A&F University College of Natural Resources and Environment Northwest A&F University Key Laboratory of Low-carbon Green Agriculture in Northwestern China Ministry of Agriculture and Rural Affairs Key Laboratory of Non-point Source Pollution of Ministry of Agricultural and Rural Affairs Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin College of Resources and Environment Southwest University Biochar Engineering Technology Research Center of Guangdong Province School of Environmental and Chemical Engineering Foshan University Department of Environmental Science University of Arizona

Shaanxi is a leading province in animal husbandry（AH） in China. However, the lack of provincial information on the characteristics and utilization potential of livestock manure（LM） hinders crucial management decisions. Therefore, we investigated the spatiotemporal distribution, availability and biogas potential of LM in Shaanxi, and examine the carbon emission reduction potential of AH.There has been a 1.26-fold increase in LM quantities in Shaanxi over the past 35 years, reaching 4635.6 × 10～4 t by 2021. LM was mainly concentrated in northern Shaanxi and the eastern part of Hanzhong. Cattle and pig manure were the primary sources of LM, with the average LM land-load of 14.57 t·ha-1in 2021. While the overall AH in Shaanxi has not exceeded the environmental capacity, the actual scales of AH in Ankang and Hanzhong have already surpassed the respective environmental capacities, posing a higher risk of N and P pollutions. In 2021, the estimated biogas energy potential of LM was 1.2 × 1011MJ. From 2012 to 2021, the average carbon emission reduction potential in Shaanxi was 22%, with an average potential scale of 10%. The results of this research provide valuable data and policy recommendations for promoting the intensive use of LM and reducing carbon emissions in Shaanxi.

关键词： Livestock manure emission estimation N and P loads biogas potential carbon emission reduction

A new component maps correction method using variable geometric parameters

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Chinese Journal of Aeronautics 2021年第4期34卷 360-374页

作者： Shaochen LI hailong tang Min CHEN School of Energy and Power Engineering Beihang UniversityBeijing 100083China Aircraft Engine Integrated System Safety Beijing Key Laboratory Beijing 100083China

Accurate engine performance models are important for model-based performance evaluation of aero engine.The accuracy of the model often depends on engine component maps,so there is a need for a method that can accurately correct the component maps of the model over a wide range.In this paper,a new method for modifying component maps is proposed,this method combines the correction of the scaling factors with the solution process of the off-design working point,and uses the adjustment of the variable geometric parameters of the engine to change the position of the working line,in order to obtain more correction results and guarantee high accuracy in a wider range.The method is validated by taking the main fan of the Adaptive Cycle Engine(ACE),an ideal power unit for a new generation of multi-purpose and ultra-wide working range aircraft,as an example.The results show that the maximum error between the corrected component maps and the target maps is less than 1%.New possibility for more precise component maps can be realized in this paper.

关键词： Adaptive cycle engine Component map correction Performance model Scaling factor Variable geometric parameter

Microstructure,elastic/mechanical and thermal properties of CrTaO_(4):A new thermal barrier material?

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Journal of Advanced Ceramics 2024年第3期13卷 373-387页

作者： Shuang Zhang Xiaohui Wang Chao Zhang Huimin Xiang Yingwei Li Cheng Fang Mingliang Li hailong Wang Yanchun Zhou School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Civil Engineering Wuhan UniversityWuhan 430072China

CrTaO_(4)(or Cr_(0.5)Ta_(0.5)O_(2))has been unexpectedly found to play a decisive role in improving the oxidation resistance of Cr and Ta-containing refractory high-entropy alloys(RHEAs).This rarely encountered complex oxide can effectively prevent the outward diffusion of metal cations from the RHEAs.Moreover,the oxidation kinetics of CrTaO_(4)-forming RHEAs is comparable to that of the well-known oxidation resistant Cr_(2)O_(3)-and Al_(2)O_(3)-forming Ni-based superalloys.However,CrTaO_(4)has been ignored and its mechanical and thermal properties have yet to be studied.To fill this research gap and explore the untapped potential for its applications,here we report for the first time the microstructure,mechanical and thermal properties of CrTaO_(4)prepared by hot-press sintering of solid-state reaction synthesized powders.Using the HAADF and ABF-STEM techniques,rutile crystal structure was confirmed and short range ordering was directly observed.In addition,segregation of Ta and Cr was identified.Intriguingly,CrTaO_(4)exhibits elastic/mechanical properties similar to those of yttria stabilized zirconia(YSZ)with Young’s modulus,shear modulus,and bulk modulus of 268,107,and 181 GPa,respectively,and Vickers hardness,flexural strength,and fracture toughness of 12.2±0.44 GPa,142±14 MPa,and 1.87±0.074 MPa·m^(1/2).The analogous elastic/mechanical properties of CrTaO_(4)to those of YSZ has spurred inquiries to lucrative leverage it as a new thermal barrier material.The measured melting point of CrTaO_(4)is 2103±20 K.The anisotropic thermal expansion coefficients areα_(a)=(5.68±0.10)×10^(-6)K^(-1),α_(c)=(7.81±0.11)×10^(-6)K^(-1),with an average thermal expansion coefficient of(6.39±0.11)×10^(-6)K^(-1).The room temperature thermal conductivity of CrTaO_(4)is 1.31 W·m^(-1)·K^(-1)and declines to 0.66 W·m^(-1)·K^(-1)at 1473 K,which are lower than most of the currently well-known thermal barrier materials.From the perspective of matched thermal expansion coefficient,CrTaO_(4)pertains to an eligible thermal barrier material fo

关键词： microstructure synthesis thermal conductivity thermal expansion coefficient melting point CrTaO_(4) mechanical and thermal properties

Time-series surface water reconstruction method(TSWR)based on spatial distance relationship of multi-stage water boundaries

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International Journal of Digital Earth 2022年第1期15卷 2335-2354页

作者： Mingyang Li Shanlong Lu Cong Du Yong Wang Chun Fang Xinru Li hailong tang Muhammad Hasan Ali Baig Harrison Odion Ikhumhen International Research Center of Big Data for Sustainable Development Goals Key Laboratory of Digital Earth ScienceAerospace Information Research InstituteChinese Academy of SciencesBeijingPeople’s Republic of China College of Resources and Environment University of Chinese Academy of SciencesBeijingPeople’s Republic of China School of Earth Sciences and Spatial Information Engineering Hunan University of Science and TechnologyXiangtanPeople’s Republic of China School of Geospatial Engineering and Science Sun Yat-Sen UniversityZhuhaiPeople’s Republic of China Institute of Geo-Information & Earth-Observation (IGEO) PMAS Arid Agriculture University RawalpindiRawalpindiPakistan Key Laboratory of Ministry of Education for Coastal Wetland Ecosystems College of the Environment and EcologyXiamen UniversityXiamenPeople’s Republic of China

Spatiotemporal continuity of surface water datasets widely known for its significance in the surface water dynamic monitoring and assessments,are faced with drawbacks like cloud influence,which hinders the direct extraction of data from time-series remote sensing images.This study proposes a Time-series Surface Water Reconstruction method(TSWR).The initial stage of this method involves the effective use of remote sensing images to automatically construct multi-stage surface water boundaries based on Google Earth Engine(GEE).Then,we reconstructed regions the reconstruction of regions with missing water pixels using the distance relationship between the multi-stage water boundaries in previous and later periods.When applied to 10 large rivers around the world,this method yielded an overall accuracy of 98%for water extraction,an RMSE of 0.41 km2.Furthermore,time-series reconstruction tests conducted in 2020 on the Lancang and Danube rivers revealed a significant improvement in the image availability.These findings demonstrated that this method could not only be used to accurately reconstruct the surface water distribution missing water images,but also to depict a more pronounced time variation characteristic.The successful application of this method on GEE demonstrates its importance for use on large scales or in global studies.

关键词： Google earth engine sentinel-2 surface water reconstruction time-series surface water data

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生物质碳点对Q235钢的缓蚀性能研究

中国腐蚀与防护学报 2024年第3期44卷 807-814页

作者：龙武剑唐杰罗启灵丘章鸿王海龙深圳大学土木与交通工程学院深圳518060 广东省滨海土木工程耐久性重点实验室深圳518060 广东裕恒工程检测技术有限责任公司广州511356

金属腐蚀威胁金属设施的安全性和可靠性,也加剧了环境污染和经济损失问题。然而,使用可持续、可再生且经济的原材料制备绿色缓蚀剂现阶段仍是有挑战性难题。本文以荔枝叶为原料制备了生物质基碳点(CDs),并采用失重法、电化学阻抗谱和动... 详细信息

金属腐蚀威胁金属设施的安全性和可靠性,也加剧了环境污染和经济损失问题。然而,使用可持续、可再生且经济的原材料制备绿色缓蚀剂现阶段仍是有挑战性难题。本文以荔枝叶为原料制备了生物质基碳点(CDs),并采用失重法、电化学阻抗谱和动电位极化曲线系统研究了其在1 mol/L HCl中对Q235钢的缓蚀性能。所获得的生物质基CDs具有丰富的含氧和含氮官能团,这些官能团使CDs在1 mol/L HCl溶液中保持稳定,具有长期有效的缓蚀性能。

关键词：碳点缓蚀剂吸附电化学实验

粤东河源盆地的深部构造、沉积序列与盆地演化

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地球学报 2024年第3期45卷 291-308页

作者：张敏李海龙唐灵祁士华旷健王文张金龙广东省有色金属地质局九三五队广东惠州516001 中国地质科学院北京100037 中国地质大学(武汉)生物地质与环境地质国家重点实验室湖北武汉430074

粤东河源盆地是东南沿海规模较大的晚中生代—新生代陆相盆地之一,发育有较为完整的晚白垩世—新近纪地层。研究该盆地的深部构造、控盆断裂、沉积序列和盆地的形成发展,对于认识东南沿海晚中生代—新近纪的大地构造演化有重要意义。通... 详细信息

粤东河源盆地是东南沿海规模较大的晚中生代—新生代陆相盆地之一,发育有较为完整的晚白垩世—新近纪地层。研究该盆地的深部构造、控盆断裂、沉积序列和盆地的形成发展,对于认识东南沿海晚中生代—新近纪的大地构造演化有重要意义。通过对野外地质调查、地球物理反射剖面和约两千米的地质科学钻探等数据资料的综合研究,查明了河源盆地为中生代—新生代沉积断陷盆地,地层结构清晰,沉积基底为早古生代地层,并建立了该盆地晚白垩世—新近纪的三阶段沉积序列;该盆地发育渐新世的火山岩,揭示了控盆边界断裂及内部构造发育特征,暗示了原型盆地的破坏发生于晚新生代:即盆地南北两侧紫金—博罗逆冲断层和河源断裂带在晚古近纪—新近纪强烈地改造了原型盆地;基于以上认识,初步恢复了河源盆地的形成演化历史,构建了河源盆地沉积序列-构造演化模式。

关键词：河源盆地沉积序列反射地震构造演化控盆断裂科学钻探东南沿海