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未知人Na(+)-K(+)-Exchanging ATPase α1亚基基因第一内含子的获得及鉴定
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作者 杨靖轩 张金三 卢圣栋 《中国医学科学院学报》 CAS CSCD 北大核心 1999年第3期159-165,共7页
目的研究人Na(+)-K(+)-ExchangingATPaseα1亚单位基因胞外区约80~130位氨基酸编码序列的未知基因组结构。方法采用聚合酶链反应(PCR)方法对人基因组DNA及cDNA文库进行扩增,限制性酶切... 目的研究人Na(+)-K(+)-ExchangingATPaseα1亚单位基因胞外区约80~130位氨基酸编码序列的未知基因组结构。方法采用聚合酶链反应(PCR)方法对人基因组DNA及cDNA文库进行扩增,限制性酶切分析扩增产物,并进行荧光测序,对测序结果进行同源性分析及剪接位点的搜索并对得到的核苷酸序列进行分析。结果人基因组DNA和cDNA经扩增后分别得到833和195bp两种不同大小的片段Fg,Fc。分析序列发现Fg与Fc相比在138~775bp处含有一638bp的插入片段,此片段与GenBank中的任何已知序列均无明显同源性。结论本研究发现了一段全新未知的人Na(+)-K(+)-ExchangingATPaseα1亚单位基因的内含子全序列,并得到了第一外显子同第二外显子之间的相对位置和序列,其在Gen-Bank的基因检索号为L76938。序列分析表明该内含子可能具有潜在的调控基因表达的功能,并含有一个可能的编码序列。 展开更多
关键词 exchanging ATPASE α1亚单位 PCR 内含子
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Preparation of SiO_2 Nanoparticles by Ion Exchanging and Study on Their Dispersion Stability
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作者 黄可知 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2004年第2期7-10,共4页
By adopting sodium silicate as a major material,SiO_2 nanoparticles (size in 8-15nm) water-dispersiod was prepared by ion exchanging.The effects of sodium silicate concentration,surface-modifying time,temperature and ... By adopting sodium silicate as a major material,SiO_2 nanoparticles (size in 8-15nm) water-dispersiod was prepared by ion exchanging.The effects of sodium silicate concentration,surface-modifying time,temperature and technological conditions on their diameter,size distribution and dispersion stability were also studied.The result show that,the hydrophilic lipophlic and hydrophilic-lipophilic SiO_(2) nanoparticles water-dispersoid can be prepared through different kinds of surface-modifiers and the optimum reaction conditions have been determined as follows:sodium silicate solution concentration:8w%;silicone dosage:3% of the total mass of nano SiO_(2) water-dispersoid;adding way and time of surface-modifier:continual dropping for 2h;surface-modifying temperature:60-70℃. 展开更多
关键词 NANOPARTICLES ion exchanging surface-modified size distribution dispersion stability
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Molecular Exchanging Energy of Anionic/Cationic Surfactants System on the Surface of Solution
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作者 DongYangHUANG XiZhangYI ZhengWuWANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第10期1077-1080,共4页
In order to study synergism of the mixed surfactants system with molecular exchanging energy (E), the Lennard-Jones formula has been firstly introduced to evaluate the E of the mixed system, CH3(CH2)nOSO 3 /CH3(CH2)nN... In order to study synergism of the mixed surfactants system with molecular exchanging energy (E), the Lennard-Jones formula has been firstly introduced to evaluate the E of the mixed system, CH3(CH2)nOSO 3 /CH3(CH2)nN+(CH3)3 directly from their molecular structure. The comparison of the calculated and the observed results showed that this method is practical. 展开更多
关键词 SURFACTANT molecule exchanging energy dimensional crystal model.
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Study on Relationship Between Arc Behavior and Joint Forming in Cold Metal Transfer Welding Technology with Polarity⁃Exchanging
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作者 Lijun Han Pengyu Lin +2 位作者 Gengwei Zhang Lihui Zhong Changhua Liu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2020年第5期81-86,共6页
Cold metal transfer with polarity⁃exchanging is a new integrated welding technology based on MIG.Due to the alternation of the positive and negative polarities of the wire,favorable control upon the deposition rate an... Cold metal transfer with polarity⁃exchanging is a new integrated welding technology based on MIG.Due to the alternation of the positive and negative polarities of the wire,favorable control upon the deposition rate and the welding shape coefficient was obtained in order to meet the desired joint design,and the related controlling principles and joint characteristics were reported.Droplet transfer physical behavior exhibited strong dependability on the studied welding parameters,such as welding voltage,welding current,wire feeding speed,and polarity⁃exchanging.This welding technology provides a new way for the welding of body⁃in⁃white(BIW)thin sheet with special demands.Moreover,the typical quality defects of MIG were greatly improved.Our study provides important technical information from the perspective of industrial application of MIG and sheds light on the higher application level of MIG in BIW welding. 展开更多
关键词 MIG cold metal transfer polarity⁃exchanging arc behavior joint shape coefficient
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Heat Exchanging Process of Metal Target under Millisecond Pulsed Laser Shocking
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作者 王洪礼 赵志培 +1 位作者 孙景 杨静 《Transactions of Tianjin University》 EI CAS 2013年第1期66-69,共4页
Laser plays an important role in synthesizing nanometer material. A three-dimensional mathematical model is established in this paper when single pulsed millisecond laser shocks the surface of the metal target at a li... Laser plays an important role in synthesizing nanometer material. A three-dimensional mathematical model is established in this paper when single pulsed millisecond laser shocks the surface of the metal target at a liquid-solid interface. By changing laser power density and target size, the temperature field variation of the metal target is investigated. Results show that the generation process of nanoparticles includes heating, melting and boiloff. 展开更多
关键词 laser shocking pulse heat exchanging
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Exchanging Experience and Promoting Cooperation——On China-German Seminar of "Women's Status and Roles in the New Era
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作者 Kong Genhong Guo Yamin 《International Understanding》 2003年第4期27-29,共3页
关键词 in On China-German Seminar of exchanging Experience and Promoting Cooperation
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Constructing the Silk Road With Sweat,Exchanging Friendship Cordially──Notes on the Visit of Mr. Turkmen, Columnist and Former Foreign Minister of Turkey
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《International Understanding》 2000年第1期7-9,共3页
关键词 Columnist and Former Foreign Minister of Turkey Constructing the Silk Road With Sweat exchanging Friendship Cordially Notes on the Visit of Mr
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Primary Study of Power-Exchanging Trans- action Model Among Price-Varied Power Plants in Practical Conditions
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作者 Chen Tianxiang Zhang Baohui 《Electricity》 2005年第3期12-16,共5页
At present, electricity price to grid of domestic power plants is priced by the national administration based on the policy of "one power plant with one electricity price to grid," which is difficult to real... At present, electricity price to grid of domestic power plants is priced by the national administration based on the policy of "one power plant with one electricity price to grid," which is difficult to realize real bidding for access to grid in practice in a short term. This paper presents one kind of power-exchanging transaction model among price-varied power plants, which will be beneficial to price-varied power plants without any loss of profits of them and guarantee state-owned assets profits in minimum loss with no promotion of average price limit by power plants. Under ideal conditions, the computation results showed the sufficiency and necessity of power-exchanging transaction and maximum similarity with the requirements of optimized resources disposition in economics. The presented model is shown to be full of practicability and has been used in some part of power market. 展开更多
关键词 different price power plant power exchange transaction model
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Calculation of the molecular exchanging energy of binary surfactants system on the surface monolayer of aqueous solution 被引量:2
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作者 WANG ZhengWu YI XiZhang 《Science China Chemistry》 SCIE EI CAS 2007年第4期468-475,共8页
By using the binary anionic/cationic surfactants system CH_(3)(CH_(2))nOSO_(3)/CH_(3)(CH_(2))nN_(+)(CH_(3))_(3)as an ex-ample,the molecular exchanging energy(ε)of adsorption on the surface monolayer of aqueous solu-t... By using the binary anionic/cationic surfactants system CH_(3)(CH_(2))nOSO_(3)/CH_(3)(CH_(2))nN_(+)(CH_(3))_(3)as an ex-ample,the molecular exchanging energy(ε)of adsorption on the surface monolayer of aqueous solu-tion has been studied.εcan be obtained with two methods.One is from the relationship betweenεand the molecule interaction parameter(β).This relationship is founded by considering that the adsorption of mixed surfactants on the surface monolayer of solution satisfies the dimensional crystal model condition under whichβcan be obtained by testing the surface tension of solution.The other is directly from the molecular structure of surfactants with the Lennard-Jones formula.The results for the studied system show that these two methods coincide well. 展开更多
关键词 SURFACTANT molecule exchanging energy dimensional crystal model
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Carbon Supported Octahedral PtNi Nanoparticles(Oct-PtNi/C)as a Cathode Catalyst for Proton Exchange Membrane Fuel Cells(PEMFCs)with Improved Activity and Durability
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作者 Zi-Wei Feng Hai-Zhong Chen +3 位作者 Xiao Duan Ling Tang Yun-Kun Zhao Long Huang 《电化学(中英文)》 北大核心 2026年第1期65-76,共12页
Proton exchange membrane fuel cells(PEMFCs)are considered as a promising renewable power source.However,the massive commercial application of PEMFCs has been greatly hindered by their high expense and less-satisfied p... Proton exchange membrane fuel cells(PEMFCs)are considered as a promising renewable power source.However,the massive commercial application of PEMFCs has been greatly hindered by their high expense and less-satisfied performance mainly due to the sluggish oxygen reduction reaction(ORR)kinetics even on state-of-the-art Pt catalyst.Octahedral PtNi nanoparticles(oct-PtNi NPs)with excellent ORR activity in a half-cell have been widely studied,while their performance in membrane electrode assembly(MEA)has much less reported.Herein,we investigated the MEA performance using the carbon supported oct-PtNi NPs(oct-PtNi/C)as the cathode catalyst.Under the mild acid washing condition,the surface Ni atoms of oct-PtNi/C were largely removed,and the performance of the MEA using the acid-leaching oct-PtNi/C(PNC-A)as the cathode catalyst was greatly improved.The maximum power density of the MEA reached 1.0 W·cm^(-2) with the cath-ode Pt loading of 0.2 mg·cm^(-2),which is 15%higher than that using Pt/C as the catalyst.After 30k cycles in the accelerated degradation test(ADT),the MEA using PNC-A as the catalyst showed a performance retention of 82%,higher than that of Pt/C(74%).The results reported here verify the possibility of using PNC-A as an advanced cathode catalyst in PEMFCs,thus enhancing the performance of PEMFCs while lowering the amount of expensive Pt. 展开更多
关键词 Proton exchange membrane fuel cell Octahedral PtNi Oxygen reduction reaction Membrane electrode assembly
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Benggang segmentation via deep exchanging of digital orthophoto map and digital surface model features
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作者 Shengyu Shen Jiasheng Chen +2 位作者 Dongbing Cheng Honghu Liu Tong Zhang 《International Soil and Water Conservation Research》 SCIE CSCD 2024年第3期589-599,共11页
Benggang is a typical fragmented erosional landscape in southern and southeastern China,posing sig-nificant risk to the local residents and economic development.Therefore,an efficient and accurate fine-grained segment... Benggang is a typical fragmented erosional landscape in southern and southeastern China,posing sig-nificant risk to the local residents and economic development.Therefore,an efficient and accurate fine-grained segmentation method is crucial for monitoring the Benggang areas.In this paper,we propose a deep learning-based automatic segmentation method for Benggang by integrating high-resolution Digital Orthophoto Map(DOM)and Digital Surface Model(DSM)data.The DSM data is used to extract slope maps,aiming to capture primary morphological features.The proposed method consists of a dual-stream convolutional encoder-decoder network in which multiple cascaded convolutional layers and a skip connection scheme are used to extract morphological and visual features of the Benggang areas.The rich discriminative information in the DOM and slope data is fused by a channel exchanging mechanism that dynamically exchanges the most discriminative features from either the DOM or DSM stream ac-cording to their importance at the channel level.Evaluation experiments were conducted on a chal-lenging dataset collected from Guangdong Province,China,and the results show that the proposed channel exchanging network based deep fusion method achieves 84.62%IoU in Benggang segmentation,outperforming several existing unimodal or multimodal baselines.The proposed multimodal segmen-tation method greatly improves the efficiency of large-scale discovery of Benggang,and thus is important for the management and restoration of Benggang in southern and southeastern China,as well as the monitoring of other similar erosional landscapes. 展开更多
关键词 Benggang segmentation Deep fusion Channel exchanging DOM DSM
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Promoting Cultural Exchange Through Thangka
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作者 LI YUAN 《China Today》 2026年第1期72-75,共4页
A Tibetan art form bridges the past and present and connects cultures around the world.THANGKA,a unique form of Tibetan sacred painting,is gaining prominence globally due to its vibrant colors,exquisite craftsmanship,... A Tibetan art form bridges the past and present and connects cultures around the world.THANGKA,a unique form of Tibetan sacred painting,is gaining prominence globally due to its vibrant colors,exquisite craftsmanship,and profound religious and cultural significance.With the acceleration of globalization,this symbol of Tibetan culture that combines artistic expression with spirituality has become a bridge for cultural exchange between the East and the West.Recently,China Today spoke to Yixi Puncog,art collector and council member of the China Association for Preservation and Development of Tibetan Culture,to learn more about Thangka art,its role in international exchange,and how it is enhancing China’s cultural soft power. 展开更多
关键词 GLOBALIZATION cultural exchange Tibetan art yixi puncogart international exchange thangka artistic expression cultural soft power
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Range shifts of four Larix species across a three-dimensional geographic gradient in response to climate change
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作者 Zhi Zhang Wenqiang Gao +1 位作者 Xiangdong Lei Jiejie Sun 《Journal of Forestry Research》 2026年第2期72-84,共13页
Climate warming is significantly altering the distribution of tree species,which holds crucial implications for China’s Larix species as they are important afforestation efforts.Understanding their optimal habitats a... Climate warming is significantly altering the distribution of tree species,which holds crucial implications for China’s Larix species as they are important afforestation efforts.Understanding their optimal habitats and environmental constraints is vital for predicting range shifts and guiding adaptive forest management.Previous studies prioritized changing climate impacts on horizontal range shifts of Larix,neglecting the influence of soil factors and range shift along altitudinal gradients.To address this,we applied an optimized MaxEnt model to assess current and future SSP126/SSP585 scenarios,three-dimensional habitat suitability(latitude,longitude,altitude)for four major Larix species(L.principis-rupprechtii,L.gmelinii,L.kaempferi,L.olgensis),while identifying key environmental drivers.Our results indicate that elevation and extreme moisture conditions universally constrain their distribution.Soil chemistry properties exhibited species-specific influences:cation exchange capacity critically shaped L.principis-rupprechtii and L.gmelinii ranges,whereas exchangeable aluminum determined L.kaempferi and L.olgensis distribution.Under future climate scenarios,habitat areas show divergent trajectories-L.principis-rupprechtii maximum gains 5.1%under SSP126,while L.kaempferi maximum expands 15.1%.Conversely,SSP585 triggered a 3.7% decline for L.gmelinii during the 2040s−2100s,and L.olgensis faces a net reduction to 0.4% by 2100s despite transient gains.Spatially,three species(L.kaempferi,L.gmelinii,L.olgensis)shifted northward,while L.principis-rupprechtii migrated northwest.All species distribution ascended altitudinally reflecting thermal adaptation strategies.These multidimensional insights enable targeted species selection for climate-resilient afforestation and underscore the need for soil-inclusive management planning. 展开更多
关键词 Climate change MaxEnt model ELEVATION Cation exchange capacity Exchangeable aluminum
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Ningxia Museum
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《China Today》 2026年第2期76-79,共4页
At the Ningxia Museum,visitors can dive into the history of the mysterious Western Xia Dynasty,as well as cultural and ethnic exchanges that occured along the ancient Silk Road centuries ago.THE area of present-day Ni... At the Ningxia Museum,visitors can dive into the history of the mysterious Western Xia Dynasty,as well as cultural and ethnic exchanges that occured along the ancient Silk Road centuries ago.THE area of present-day Ningxia Hui Autonomous Region in northwest China was a vital corridor of the ancient Silk Road.Around a thousand years ago,Yuan Hao,leader of the Tangut people,established the Western Xia(also known as Xixia)Dynasty(1038-1227)on this land,which coexisted with the Song,Liao,and Jin dynasties across China for nearly 200 years. 展开更多
关键词 cultural ethnic exchanges Silk Road Ningxia Museum Yuan Hao Western Xia Dynasty Cultural Exchange
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Defence Technology Aims and Scope
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《Defence Technology(防务技术)》 2026年第2期F0002-F0002,共1页
Defence Technology(ISSN 2214-9147(O);2096-3459(P)),sponsored by China Ordnance Society,is published monthly and aims to become one of the well-known comprehensive journals in the world,which reports on the breakthroug... Defence Technology(ISSN 2214-9147(O);2096-3459(P)),sponsored by China Ordnance Society,is published monthly and aims to become one of the well-known comprehensive journals in the world,which reports on the breakthroughs in defence technology by building up an international academic exchange platform for the defence technology related research.It publishes original research papers having direct bearing on defence,with a balanced coverage on analytical,experimental,numerical simulation and applied investigations.It covers various disciplines of science,technology and engineering. 展开更多
关键词 defence technology applied investigation original research papers analytical methods academic exchange platform breakthroughs experimental methods international academic exchange
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Notes for Contributors
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《Chinese Journal of Chemical Engineering》 2026年第1期I0002-I0002,共1页
The Chinese Journal of Chemical Engineering is the official journal of The Chemical Industry and Engineering Society of China and published by the Chemical Industry Press Co.,Ltd.The aim of the journal is to develop t... The Chinese Journal of Chemical Engineering is the official journal of The Chemical Industry and Engineering Society of China and published by the Chemical Industry Press Co.,Ltd.The aim of the journal is to develop the international exchange of scientific and technical information in the field of chemical engineering.Submission of Papers All papers will be submitted on line. 展开更多
关键词 chemical engineeringsubmission international exchange technical information scientific information develop international exchange scientific technical information chemical engineering chemical industry engineering society
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THOUGHTS FOR A NEW ERA
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《ChinAfrica》 2026年第2期6-6,共1页
On 8 January,President Xi Jinping sent a congratulatory letter to the launch ceremony of the 2026 China-Africa Year of People-to-People Exchanges held at the African Union headquarters in Addis Ababa,Ethiopia.Selected... On 8 January,President Xi Jinping sent a congratulatory letter to the launch ceremony of the 2026 China-Africa Year of People-to-People Exchanges held at the African Union headquarters in Addis Ababa,Ethiopia.Selected excerpts follow:The Year of People-to-People Exchanges marks a significant step to further cement public support for China-Africa friendship at a new historical starting point. 展开更多
关键词 China Africa Year People People Exchanges historical starting point public support China Africa friendship Addis Ababa Ethiopia African Union people people exchanges
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The Timeless Allure of Yangzhou
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作者 ZHOU LIN 《China Today》 2026年第3期23-23,共1页
The book Yangzhou:The Biography,written by Wei Minghua,is part of the Biographies of 100 Cities Along the Silk Road series.Rather than writing a general history account of this millennia-old city,this book aims to ans... The book Yangzhou:The Biography,written by Wei Minghua,is part of the Biographies of 100 Cities Along the Silk Road series.Rather than writing a general history account of this millennia-old city,this book aims to answer one central question:What is Yangzhou’s relationship with the Silk Road?This requires examining several aspects:the significant historical facts about Yangzhou in China’s foreign exchanges,why Yangzhou became a renowned hub for such interaction,and the stories of ordinary people in today’s Yangzhou. 展开更多
关键词 Historical Facts Ordinary People HUB Silk Road BIOGRAPHY Foreign Exchanges Yangzhou
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Covalent organic framework ionomers enable synergistic efficient transport of protons and oxygen in medium-temperature proton exchange membrane fuel cells
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作者 Zijie Lin Qing Li 《Chinese Chemical Letters》 2026年第1期7-9,共3页
Covalent organic framework ionomers enable synergistic efficient transport of protons and oxygen in medium-temperature proton exchange membrane fuel cells Proton exchange membrane fuel cells(PEMFCs),as clean and effic... Covalent organic framework ionomers enable synergistic efficient transport of protons and oxygen in medium-temperature proton exchange membrane fuel cells Proton exchange membrane fuel cells(PEMFCs),as clean and efficient energy technologies,are constrained in their performance enhancement by the sluggish oxygen reduction reaction(ORR)kinetics at the cathode,anode CO poisoning(e.g.,from methanol crossover)and intricate water management dilemmas[1]. 展开更多
关键词 covalent organic framework ionomers proton exchange membrane fuel cells pemfcs proton exchange membrane fuel cells sluggish oxygen reduction reaction orr kinetics PROTONS water management dilemmas OXYGEN
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Guide for Authors
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《Chinese Journal of Aeronautics》 2026年第1期F0003-F0003,共1页
About Journal Chinese Journal of Aeronautics(CJA)is a comprehensive academic journal dealing with the fields of aeronautics and astronautics.It reports researches concerning the two fields in China and abroad to promo... About Journal Chinese Journal of Aeronautics(CJA)is a comprehensive academic journal dealing with the fields of aeronautics and astronautics.It reports researches concerning the two fields in China and abroad to promote the academic exchange.Founded in 1988 and sponsored by the Chinese Society of Aeronautics and Astronautics and Beihang University. 展开更多
关键词 AERONAUTICS ASTRONAUTICS academic exchange academic journal RESEARCH journal aeronautics cja
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