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Aero-structural design of joined-wing aircraft based on high-fidelity model

Chinese Journal of Aeronautics 2024年第4期37卷 363-377页

作者： Cheng HE Fengjiang ZHAN Luchuang ma Gang CHEN jianying ma Unmanned Air Vehicle Research Institute Nanjing University of Aeronautics and AstronauticsNanjing 210016China Key Laboratory of Advanced Technology for Small and Medium-sized UAV Ministry of Industry and Information TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016China Aerospace System Engineering Shanghai Shanghai 201108China

The joined-wing configuration reduces induced drag and structural weight by connecting the rear wing to the front wing.In addition,the rear wing can replace the role of the horizontal tail of a conventional aircraft,thus eliminating the aerodynamic drag and weight associated with the horizontal tail.This particular shape creates a highly coupled relationship between aerodynamics and structure,which must be fully considered during the overall design process to enhance aircraft performance.In this research,an aero-structural design model of the joined-wing aircraft is constructed based on high-fidelity computational fluid dynamics and structural finite element methods.The model is able to obtain accurate aerodynamic loads for the non-planar wing and to simulate the statically indeterminate structure of the closed wing configuration.The influence of the joined-wing shape parameters on the aerodynamic and structural disciplines,as well as the influence of geometric nonlinear characteristics,deformation constraints and buckling constraints on the structural weight are all taken into consideration.The model is applied to complete the aero-structural design optimization of a high-altitude long-endurance joined-wing aircraft,and wind tunnel tests are conducted.The test results verify the credibility of the design model proposed and the validity of the design environment.

关键词： Joined-wing configuration Aircraft design Aero-structural design Finite element Wind tunnel test

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Application of stable isotope techniques to the study of soil salinization

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Journal of Arid Land 2011年第4期3卷 285-291页

作者： YongQin CUI jianying ma Wei SUN Dunhuang Gobi and Desert Ecology and Environment Research Station Cold and Arid Regions Environmental and Engineering Research Institute CAS Lanzhou 730000 China Key Laboratory of Vegetation Ecology Ministry of Education Institute of Grassland Sciences Northeast Normal University Changchun 130024 China

In this paper, we reviewed the progress in the application of stable isotope techniques to the study of soil salinization. As a powerful technique, stable isotopes have been widely used in the studies of soil water evaporation, the dynamics of soil salinization and salt-tolerant plant breeding. The impact of single environmental factors on plant isotope composition has been the focus of previous studies. However, the impact of multiple environmental factors on plant isotope composition remains unclear and needs to be carefully studied. In order to gain insights into soil salinization and amelioration, especially soil salinization in arid and semiarid areas, it is essential to employ stable isotope techniques and combine them with other methods, such as located field observation and remote sensing technology.

关键词： stable isotope soil water evaporation soil salinization dynamic salt-tolerant plants breeding

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A preliminary study of water use strategy of desert plants in Dunhuang,China

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Journal of Arid Land 2015年第1期7卷 73-81页

作者： YongQin CUI jianying ma Wei SUN JiaHuan SUN ZhengHu DUAN Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Ministry of Education Key Laboratory of Vegetation Ecology Institute of Grassland Science Northeast Normal University

Water is a restrictive factor for plant growth and ecosystem stability in arid and semiarid areas. The dynamics of water availability in soils and water use by plants are consequently critical to ecosystem functions, e.g. maintaining a high resistance to the changing climate. Plant water use strategies, including water-use efficiency （WUE） and the main water source that a plant species utilizes, play an important role in the evaluation of stability and sustainability of a plantation. The water use strategies of desert plants （Tamarix chinensis, Alhagi sparsifolia, Elaeagnus angustifolia, Sophora alopecuroides, Bassia dasyphylla and Nitraria sphaerocarpa） in three different habitats （saline land, sandy land and Gobi） in Dunhuang （located in the typical arid area of northwestern China） were studied. The stable isotope of oxygen was used to determine the main water source and leaf carbon isotope discrimination was used to estimate the long-term WUE of plant species in the summer of 2010. The results suggest that： 1） the studied desert plants took up soil water below the depth of 80 cm; 2） T. chinensis in the three habitats used deeper soil water and T. chinensis in the Gobi site had higher WUE than those in the saline land and the sandy land. The results indicated that desert plants in Dunhuang depended on stable water source and maintained high WUE to survive in water limited environments.

关键词： desert plant stable isotope water source water-use efficiency Dunhuang

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Active greeting technique: a mother-and-child catheter based technique to facilitate retrograde wire externalization in recanalization of coronary chronic total occlusion

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Science Bulletin 2018年第23期63卷 1565-1569页

作者： Junbo Ge Lei Ge Bin Zhang Xin Zhong jianying ma Leisheng Ru Tao Hu Juying Qian 无 Shanghai Institute of Cardiovascular Diseases Zhongshan HospitalFudan UniversityShanghai 200022China Institutes of Biomedical Sciences.Fudan University Shanghai 200032China Department of Cardiology Guangdong Cardiovascular InstituteGuangdong General Hospital Guangzhou510080China Department of Cardiology Bethune International Peace HospitalShzjiazhuang 050082China Department of Cardiology Xijing HospitalXi'an 710032China Chronic Total Occlusion Club China

Although retrograde approach has greatly improved the success rate of percutaneous coronary intervention(PCI) for coronary chronic total occlusion(CTO), retrograde wire externalization still remains challenging and time-consuming in some cases. Cases utilizing ‘‘Active Greeting Technique(AGT)", a mother-and-child catheter based technique to facilitate retrograde wire externalization, were extracted from Chronic Total Occlusion Club, China(CTOCC) database. AGT was performed by deep intubation a mother-and-child catheter(GuidezillaTMextension, 4 or 5 Fr inner catheter, and etc.) in combination with either reverse controlled antegrade or retrograde subintimal tracking(CART) technique or retrograde wire crossing technique. A total of 111 patients with 112 CTO lesions treated with this technique were retrospectively analyzed. Reverse CART technique and retrograde wire crossing technique were performed in 90.2% and 9.8% of all procedures. The utilization of GuidezillaTMextension, 4 Fr, and 5 Fr inner catheter accounted for 94.6%, 3.6%, and 1.8%, respectively. Externalization of retrograde wire was successful in all cases. No procedural complications were adjudicated to AGT. Complications independent of AGT included two target vessel perforations and two collateral perforations. No in-hospital major adverse cardiac events were found. AGT is a feasible and safe technique that facilitates retrograde wire externalization.

关键词： Percutaneous coronary intervention Chronic total occlusion Retrograde wire externalization Active greeting technique

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韩国与北约安全合作的深化和升级

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东北亚学刊 2024年第2期 27-47,145页

作者：马建英赵敏瑶山东大学东北亚学院山东大学国际问题研究院山东大学海洋战略与发展研究中心威海264209 韩国延世大学国际大学院首尔03722

韩国与北大西洋公约组织(简称“北约”)之间的安全合作虽不久远,但发展迅速。特别是近年,随着中美战略博弈加剧,以及北约不断转向亚太,双方安全合作进一步升级,合作领域不断深化,合作机制得到加强,合作对象日益拓展。双方基于利益需求... 详细信息

韩国与北大西洋公约组织(简称“北约”)之间的安全合作虽不久远,但发展迅速。特别是近年,随着中美战略博弈加剧,以及北约不断转向亚太,双方安全合作进一步升级,合作领域不断深化,合作机制得到加强,合作对象日益拓展。双方基于利益需求相互借重,势必加剧朝鲜半岛紧张局势,恶化中国周边安全环境,给中韩关系带来冲击。双方安全合作势必推动北约“亚太化”趋势。该趋势促进跨大西洋和跨太平洋间形成更深层次勾连,利于美国推动“两洋战略”联动效应,在欧亚大陆两端形成对中俄的“双压制”态势。双方安全合作同时助推亚太“北约化”,以北约亚太伙伴国为基础,亚太地区可能出现类似于北约的多边安全联盟。

关键词：尹锡悦政府北约“亚太化” 亚太“北约化” 安全合作中韩关系

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Variations of organic carbon isotopic composition and its environmental significance during the last glacial on western Chinese Loess Plateau

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Chinese Science Bulletin 2006年第13期51卷 1593-1602页

作者： CHEN Fahu RAO Zhiguo ZHANG Jiawu JIN Ming ma jianying Center for Arid Environment and Paleoclimate Research (CAEP) Key Laboratory of Western China's Environmental System of Ministry of Education Lanzhou University Lanzhou 730000 China Key Laboratory of marginal Sea Geology Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

A high-resolution loess section in the western Chinese Loess Plateau, Yuanbao Section, was sampled for organic carbon isotopic analyses. The soil organic carbon isotope (δ13Corg) varied be- tween ?22.6‰ and ?27.5‰ during the last glacial at the section. During the last interstadial, the δ 13Corg values were more negative than those in both early and late periods of the last glacial by 4‰. The iso- topic composition indicates a coupled response of the pure C3 plants to the temperature, precipitation and the concentration of atmospheric CO2. Decrease in temperature and the atmospheric CO2 concentration from the last interstadial to Last Glaicial maximum (LGM) caused the organic carbon isotopes to be- come positive by 1.5‰―2.0‰. The amplitude of 4‰ in the δ 13Corg variation during the last glacial should be mainly caused by the precipitation change. Therefore, the δ 13Corg variations of the Yuanbao Section during the last glacial period documented the large-amplitude fluctuation of the monsoon precipita- tion, which is estimated to be 250―310 mm more during the last interstadial than that in the LGM, and 100 mm more than that during early last glacial. The rapid changes of the monsoon precipitation on mil-lennial scale during the last glacial have also been recorded in the isotopic variations in Yuanbao loess section. As the isotopic composition varies compli- catedly as shown in the loess-paleosol sequence, it cannot be simply attributed to the abundances of C3 and C4 plants or be used as an indicator of the summer monsoon variations.

关键词：有机碳同位素成品冰黄土高原华西地区

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Fault-sand combination modes and hydrocarbon accumulation in Binhai fault nose of Qikou Sag, Bohai Bay Basin, East China

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Petroleum Exploration and Development 2019年第5期46卷 919-934页

作者： ZHOU Lihong HAN Guomeng DONG Yueqi SHI Qianru ma jianying HU Jinnan REN Shichao ZHOU Kejia WANG Jincheng SI Weiliu Dagang Oilfield Company PetroChinaTianjin 300280China

Based on seismic and logging data,taking the downthrow fault nose of Binhai fault in Qikou Sag as the object of study,we analyzed fault characteristics,sand body distribution,fault-sand combinations and hydrocarbon accumulation to reveal the hydrocarbon enrichment law in the fault-rich area of fault depression lake basin.The results show that the Binhai Cenozoic fault nose is characterized by east-west zoning,the main part of the western fault segment is simple in structure,whereas the broom-shaped faults in the eastern segment are complex in structure,including several groups of faults.The difference of fault evolution controls the spatial distribution of sand bodies.The sand bodies are in continuous large pieces in the downthrow fault trough belt along the Gangdong Fault in the middle segment of the fault nose,forming consequent fault-sand combination;whereas the fault activity period of the eastern part of the fault nose was later,and the sand bodies controlled by paleogeomorphology are distributed in multi-phase north-south finger-shaped pattern,forming vertical fault-sand combination pattern matching with the fault.The configuration between faults and sand bodies,and oil sources and caprocks determine the vertical conductivity,plane distribution and vertical distribution of oil and gas.Two oil and gas accumulation modes,i.***.single main fault hydrocarbon supply-fault sand consequent matching-oil accumulation in multi-layers stereoscopically and fault system transportation-fault sand vertical matching-oil accumulation in banded overlapping layers occur in the middle and eastern segments of the fault nose respectively,and they control the difference of oil and gas distribution and enrichment degree in the Binhai fault nose.

关键词： Bohai Bay Basin Qikou Sag Binhai fault nose sandstone development mechanism fault-sand combination oil and gas accumulation reservoir control mechanism

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Formation conditions and enrichment model of retained petroleum in lacustrine shale: A case study of the Paleogene in Huanghua depression, Bohai Bay Basin, China

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Petroleum Exploration and Development 2020年第5期47卷 916-930页

作者： ZHAO Xianzheng ZHOU Lihong PU Xiugang JIN Fengming SHI Zhannan HAN Wenzhong JIANG Wenya HAN Guomeng ZHANG Wei WANG Hu ma jianying PetroChina Dagang Oilfield Company Tianjin 300280China

Compared with marine facies shale strata,lacustrine shale strata are more complicated in geological conditions,and thus more difficult to explore and develop.To realize economic exploration and development of lacustrine shale oil,the geological regularities of accumulation and high yield of retained movable petroleum in shale should be understood first.In this work,taking the shale strata of Kong 2 Member and Sha 3 Member in the Paleogene of Huanghua depression in the Bohai Bay Basin as examples,based on the previous joint analysis results of over ten thousand core samples and the latest oil testing,production test and geochemical data of more than 30 horizontal wells,accumulation conditions and models of retained movable petroleum in lacustrine shale were studied comprehensively.The study shows that at moderate organic matter abundance(with TOC from 2%to 4%),shale strata have the best match between oil content and brittleness,and thus are rich in oil and good in fracability.Moderate ancient lake basin size and moderate sediment supply intensity are the internal factors leading to best coupling of organic matter abundance and brittle mineral content in the shale formation.Moderate thermal evolution maturity of Ro of 0.7%–1.0%(at burial depth of 3200 to 4300 m)is the interval where oil generation from thermal evolution and oil adsorption by kerogen in shale layers match best,and retained movable petroleum is high in proportion.Moderate diagenetic evolution stage(3200 to 4300 m in the middle diagenetic stage A)is conducive to the formation of a large number of dissolved pores and organic matter pores,which provide storage space for shale oil enrichment.Moderate development degree of natural fractures(without damaging the shale oil roof and floor sealing conditions)is conducive to the storage,seepage and preservation of shale oil.The research results have overthrown the general understanding that high organic matter abundance,high maturity,and high development degree of natural fractures are conducive to shale oil e

关键词： lacustrine shale retained hydrocarbon movable hydrocarbon shale oil enrichment model Kong 2 Member Sha 3 Member Huanghua Depression Bohai Bay Basin

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Global Climate Diplomacy:Origin and Development

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China International Studies 2010年第3期30卷 157-172页

作者： ma jianying PhD candidate at the School for International Relations and Public Affairs FudanUniversity

With the deterioration of global climate in recent years,climate change remains as a hot issue to which the international community pays close attention.2007 could be called the'Year of Climate Change'.In April,the United Nations Security Council held an open debate on climate change and international security for the first time,greatly enhancing the importance of

关键词：全球气候起源气候变化

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Identification of new cotton fiber-quality QTL by multiple genomic analyses and development of markers for genomic breeding

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The Crop Journal 2024年第3期12卷 866-879页

作者： Haozhe Tan Binghui Tang Mengling Sun Qiulu Yin Yizan ma jianying Li Pengcheng Wang Zhonghua Li Guannan Zhao maojun Wang Xianlong Zhang Chunyuan You Lili Tu National Key Laboratory of Crop Genetic Improvement Hubei Hongshan LaboratoryHuazhong Agricultural UniversityWuhan 430070HubeiChina Cotton Research Institute Shihezi Academy of Agriculture ScienceShihezi 832000XinjiangChina

Cotton fiber is one of the main raw materials for the textile industry.In recent years,many cotton fiber quality QTL have been identified,but few were applied in breeding.In this study,a genome wide association study(GWAS)of fiber-quality traits in 265 upland cotton breeding intermediate lines(GhBreeding),combined with genome-wide selective sweep analysis(GSSA)and genomic selection(GS),revealed 25 QTL.Most of these QTL were ignored by only using GWAS.The CRISPR/Cas9 mutants of GhMYB_D13 had shorter fiber,which indicates the credibility of QTL to a certain extent.Then these QTL were verified in other cotton natural populations,5 stable QTL were found having broad potential for application in breeding.Additionally,among these 5 stable QTL,superior genotypes of 4 showed an enrichment in most improved new varieties widely cultivated currently.These findings provide insights for how to identify more QTL through combined multiple genomic analysis to apply in breeding.

关键词： Cotton fiber quality breeding GWAS Genome-wide selective sweep analysis Genomic selection InDel markers

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