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正常类飞机自然结冰试飞适航审定技术

航空学报 2024年第1期45卷 188-209页

作者：高郭池张波全敬泽尹崇丁丽姜裕标中国民用航空沈阳航空器适航审定中心沈阳110043 哈尔滨飞机工业集团飞机设计研究所哈尔滨150066 中国空气动力研究与发展中心绵阳621000

民用飞机如果申请已知结冰条件下飞行(FIKI),应按照除防冰相关适航规章条款要求进行表明符合性适航验证,其中自然结冰试飞是必须完成的重要环节。以Y12F飞机自然结冰试飞为例,以中国民用航空局(CAAC)和美国联邦航空管理局(FAA)发布的已... 详细信息

民用飞机如果申请已知结冰条件下飞行(FIKI),应按照除防冰相关适航规章条款要求进行表明符合性适航验证,其中自然结冰试飞是必须完成的重要环节。以Y12F飞机自然结冰试飞为例,以中国民用航空局(CAAC)和美国联邦航空管理局(FAA)发布的已知结冰条件下飞行相关指导文件为基础,结合Y12F飞机自然结冰试飞适航审定过程,分析总结了除防冰系统、测试设备及安装、试飞空域、结冰大气条件、试飞内容、试飞状态、试飞程序、试飞结果和分析以及结冰探测、结冰大气探测、冰积聚情况监测等方面的适航审定要求和关键技术,并对试飞过程中发现问题的分类、解决措施、设计改进方案以及完成的补充验证工作进行了阐述。经CAAC和FAA同步审查,Y12F飞机获得CAAC和FAA已知结冰条件下飞行的批准。构建的自然结冰试飞适航审定方法,成为FIKI适航验证重要实践指导性材料。

关键词：自然结冰试飞除防冰系统结冰探测试飞程序适航审定

Effect of biochar application on rice,wheat,and corn seedlings in hydroponic culture

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Journal of Environmental Sciences 2024年第1期135卷 379-390页

作者： yingjie yin Jikai Li Sihang Zhu Qing Chen chong Chen Yukui Rui Jianying Shang College of Land Science and Technology China Agricultural UniversityKey Laboratory of Plant-Soil InteractionsMinistry of Educationand Key Laboratory of Arable Land Conservation in North ChinaMinistry of Agriculture and Rural AffairsBeijing 100193China Agricultural Management Institute Ministry of Agriculture and Rural AffairsBeijing 102208China College of Resources and Environmental Sciences China Agricultural UniversityBeijing Key Laboratory of Farmland Soil Pollution Prevention and RemediationBeijing 100193China

In recent years,biochar has attracted considerable attention for soil quality improvement and carbon sequestration due to its unique physicochemical ***,the mechanism by which biochar application negatively affects the growth of crop seedlings has not been fully *** this study,a hydroponic experiment was conducted to evaluate the response of rice,wheat,and corn seedlings to biochar application(CK,0 g/L;BC1,0.5 g/L;and BC2,1.0 g/L).Compared with the CK treatment,the BC1 and BC2 treatments decreased the fresh shoot and root weights of rice and corn seedlings(P0.05).For the contents of nutrient elements in seedlings,both BC1 and BC2 treatments hindered the roots from absorbing Fe and Cu and increased the uptake of Ca and *** with the CK treatment,the translocation factor(TF)values of Ca,Mn,and Zn were significantly decreased especially in rice seedlings(35.3%-36.8%,68.7%-76.5%,and 29.8%-22.0%,respectively)under the BC1 and BC2 treatments,while only Mn was significantly decreased in wheat and corn seedlings(P<0.05).Transmission electron microscope(TEM)analysis of root cross-sections showed that nano-sized biochar particles(10~23 nm)were found in the root cells under BC2 treatment *** findings reveal that a large amount of biochar application can reduce nutrient absorption and translocation,and hinder rice,wheat,and corn seedlings,particularly rice seedling,in hydroponic system.

关键词： Biochar Toxicity Seedling growth Hydroponic cultivation

Genomic insights into adaptation to bipedal saltation and desert-like habitats of jerboas

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Science China Life Sciences 2024年第9期67卷 2003-2015页

作者： Simin Chai Yujie chong Daiqing yin Qiang Qiu Shixia Xu Guang Yang Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou) Jiangsu Key Laboratory for Biodiversity and Biotechnology School of Life Sciences Nanjing Normal University School of Ecology and Environment Northwestern Polytechnical University

Jerboas is a lineage of small rodents displaying atypical mouse-like morphology with elongated strong hindlimbs and short forelimbs. They have evolved obligate bipedal saltation and acute senses, and been well-adapted to vast desert-like habitats. Using a newly sequenced chromosome-scale genome of the Mongolian five-toed jerboa(Orientallactaga sibirica), our comparative genomic analyses and in vitro functional assays showed that the genetic innovations in both protein-coding and non-coding regions played an important role in jerboa morphological and physiological adaptation. Jerboa-specific amino acid substitutions, and segment insertions/deletions(indels) in conserved non-coding elements(CNEs) were found in components of proteoglycan biosynthesis pathway(XYLT1 and CHSY1), which plays an important role in limb development. Meanwhile, we found specific evolutionary changes functionally associated with energy or water metabolism(e.g., specific amino acid substitutions in ND5 and indels in CNEs physically near ROR2) and senses(e.g., expansion of vomeronasal receptors and the FAM136A gene family) in jerboas. Further dual-luciferase reporter assay verified that some of the CNEs with jerboa-specific segment indels exerted a significantly different influence on luciferase activity, suggesting changes in their regulatory function in jerboas. Our results revealed the potential molecular mechanisms underlying jerboa adaptation since the divergence from the Eocene-Oligocene transition, and provided more resources and new insights to enhance our understanding of the molecular basis underlying the phenotypic diversity and the environmental adaptation of mammals.

关键词： jerboa adaptive evolution comparative genomics conserved non-coding elements bipedal saltation

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Development of the electric automatic steering system for agricultural vehicles

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 209-214页

作者： Guangshun An chong Yu Juan Du Xiang yin Youliang Ni Chengqian Jin School of Agricultural Engineering and Food Science Shandong University of TechnologyZibo 255000ShandongChina Nanjing Research Institute for Agricultural Mechanization of Ministry of Agriculture and Rural Affairs Nanjing 210014China

Automatic guidance of agricultural vehicles requires automatic execution of operation commands received from the navigation controller by using electronically controlled mechanisms for wheel steering,speed changing and work *** steering contributes as a prerequisite technique in automatic and semi-automatic agricultural *** research aimed to develop an electric automatic steering system that was compact in its structure and integrated into original steering mechanism in a simply and convenient way for aftermarket modification.A brushless motor and reducer assembly was utilized to provide an adequate steering torque instead of manual maneuver.A rapid assembling approach was proposed by passing the steering shaft through the hollow output shaft.A digital proportional-integral-differential(PID)algorithm was implemented to calculate the rotation speeds and directions by comparing the desired angle and the actual angle,which was implemented in a printed circuit board with a microcontroller unit(MCU)and interface *** unmanned wheeled tractor was applied as test platform to integrate the newly developed electric automatic steering *** were conducted to evaluate its performance in terms of stability and *** autonomous navigation system guided the tractor along target paths in the field by sending steering commands to the electric automatic steering *** results show that the steering angle error was less than 0.81°when desired steering angle was less than 10°.The lateral error difference was no more than 4.76 cm when repeating following the same target path,which indicated that the electric automatic steering system responded accurately and robustly to steering commands.

关键词： automatic steering automatic navigation agricultural vehicles

Periodic Structures of Rossby Wave under Influence of Dissipation

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Communications in Theoretical Physics 2007年第1期47卷 35-40页

作者： CHEN Zhe LI chong-yin FU Zun-Tao LASG Institute of Atmospheric Physics Academy of Sciences Beijing 100029 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China Institute of Meterology University of Science and Technology of the PLA Nanjing 211101 China School of Physics Peking University Beijing 1000871 China State Key Laboratory for Turbulence and Complex Systemi Peking University Beijing 100871 China

有驱散的影响的一个简单 barotropic 潜力涡度方程被使用在 tropicalatmophere 在 shear 流动调查非线性的 Rossby 波浪。由减少的不安方法，我们导出旋转 KdV (rKdV 为短) 方程。然后在 Jacobi 椭圆形的功能的帮助下，我们为这些 Ross... 详细信息

有驱散的影响的一个简单 barotropic 潜力涡度方程被使用在 tropicalatmophere 在 shear 流动调查非线性的 Rossby 波浪。由减少的不安方法，我们导出旋转 KdV (rKdV 为短) 方程。然后在 Jacobi 椭圆形的功能的帮助下，我们为这些 Rossby 波浪获得各种各样的周期的结构。驱散为合理形式的这些周期的结构是很重要的，这被显示出。

关键词：罗斯比波周期结构正压位势涡量方程耗散 KdV方程

Advanced solar materials for thin-film photovoltaic cells

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Frontiers of physics 2011年第2期6卷 177-196页

作者： Fu-qiang HUANG chong-yin YANG Dong-yun WAN College of Engineering and College of Chemistry and Molecular Engineering Peking University Beijing 100871 China CAS Key Laboratory of Materials for Energy Conversion Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences Suzhou 215123 China

As one of the most promising solutions for the green energy, thin-film photovoltaic cell technology is still immature and far from large-scale industrialization. The major issue is getting low cost and stable module efficiency. To solve these problems, a large amount of advanced solar materials have been developed to improve all parts of solar cell modules. Here, some new solar material developments applied in different critical parts of chalcogenide thin-film photovoltaic cells are reviewed. The main efforts are focused on improving light trapping and antireflection, internal quantum efficiency and collection of photo-generated carriers.

关键词： thin-film solar cell thin films CIGS CdTe

Further Study of Typhoon Tracks and the Low-Frequency (30-60 Days) Wind-Field Pattern at 850 hPa

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Atmospheric and Oceanic Science Letters 2010年第6期3卷 319-324页

作者： TIAN Hua LI chong-yin State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical FluidDynamics （LASG） Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Editorial Board of the Institute of Atmospheric Physics Beijing 100029 China Institute of Meteorology the People＇s Liberation Army （PLA） University of Science and Technology Nanjing 211101 China

The association of typhoon tracks over the western Pacific with the low-frequency wind-field pattern of atmospheric intraseasonal (30-60 days) oscillation at 850 hPa is further studied by using observational data analyses. Comparative analyses of the composite wind fields at 850 hPa, contrasting the atmospheric intraseasonal oscillation (ISO) with the original circulation, show that the typhoon tracks are closely related to the wind pattern of the ISO but are not obviously related to the original wind fields. Case studies of two typhoons in 2006 also show that the low-frequency wind-field pattern, particularly the maximum-value line (belt) of low-frequency cyclonic vorticity at 850 hPa, is closely related to the typhoon track. Therefore, the lowfrequency circulation pattern and the maximum-value line (belt) of low- frequency cyclonic vorticity at 850hPa can be used to predict typhoon tracks over the northwestern Pacific.

关键词：台风路径低频率大气季节内振荡场模风场分布流通模式西北太平洋西太平洋

A comparative study of the pore characteristics and phenol adsorption performance of activated carbons prepared from oil-palm shell wastes by steam and combined steam-chemical activation

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Green Chemical Engineering 2024年第1期5卷 85-96页

作者： Aik chong Lua School of Mechanical and Aerospace Engineering Nanyang Technological University50 Nanyang AvenueSingapore639798Republic of Singapore

Oil-palm shell wastes were successfully converted into useful activated carbons in a systematic and novel approach by optimizing the pyrolysis conditions and subsequent steam activation conditions to maximize the BET surface *** optimal activation conditions were a steam flow rate of 1.13 kg/h,hold time of 1.5 h and temperature of 950℃,yielding BET areas of 1432.94 and 1382.95 m^(2)/g for nitrogen-pyrolyzed and vacuumpyrolyzed chars,*** steam-chemical activation,one-step activation of oil-palm shell in steam with potassium carbonate(K_(2)CO_(3)),sodium carbonate(Na_(2)CO_(3))or potassium chloride(KCl)was conducted,resulting in BET area output order of shell/K_(2)CO_(3)(710.56 m^(2)/g)>shell/KCl(498.55 m^(2)/g)>shell(366.7 m^(2)/g)>shell/Na_(2)CO_(3)(326.62 m^(2)/g).This study reported the first use of KCl and Na_(2)CO_(3)as chemical reagents in one-step steam-chemical activation of ***-activated carbon exhibited retardation of tar formation property,resulting in better pore development than pure steam activated *** adsorption of activated carbon is not only a function of the BET surface area but also the type of pyrolysis used prior to physical *** carbon(BET area of 1192.29 m^(2)/g)pyrolyzed under vacuum could adsorb 87%more phenol than that pyrolyzed in nitrogen flow which had a higher BET area of 1432.94 m^(2)/*** adsorption capacities of activated carbons are:shell pyrolyzed under vacuum(275.5 mg/g)>shell pyrolyzed in N_(2)flow(147.1 mg/g)>shell/K_(2)CO_(3)(145.7 mg/g)>shell without pyrolysis(12.1 mg/g).These activated carbons would be highly suitable in industry processes to remove phenolic contaminants.

关键词： Pore surface area Oil-palm shell Activated carbon Steam activation Phenol adsorption

Physical Essence of the “Predictability Barrier”

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Atmospheric and Oceanic Science Letters 2009年第5期2卷 290-294页

作者： Li chong-yin Ling Jian LASG Institute of Atmospheric Physics Chinese Academy of Science Beijing 100029 China

Although the "predictability barrier" is a scientific problem brought forward during the middle 1990’s,it has yet to be clearly *** this paper,the authors used model results to study the "predictability barrier" of some atmospheric (climatic) systems,including the equatorial Pacific sea surface temperature (SST),East Asia trough (EAT),and South Asia wind field (monsoon).It is shown that the "predictability barrier" appeared not only in predicting the SST in the equatorial Pacific,but also in predicting the atmospheric circulation systems,such as the EAT and the *** "predictability barrier" for predicting the different climate systems appeared not only in spring,but also in different *** appeared in spring for the equatorial Pacific SST,in summer for the EAT,and in fall and winter for the *** analyses showed that the fundamental physical essence of the "predictability barrier" is the seasonal variability characteristics of the atmospheric (climate) *** "predictability barrier" would occur when the system was at its weakest or worst continuous ***,the models and error patterns also had an important impact on the "predictability barrier";good models and special error patterns can minimize the "predictability barrier".

关键词： 'predictability barrier' physical essence atmospheric(climatic)system