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一种高精度星载磁强计系统级标定方法

中国空间科学技术（中英文） 2024年第3期44卷 174-179页

作者：孟立飞徐超群肖琦刘超波耿晓磊陈德祥易忠张铁龙哈尔滨工业大学(深圳) 深圳518055 北京卫星环境工程研究所北京100094 北京控制工程研究所北京100190 奥地利科学院空间研究所格拉茨A-8042

星载三轴磁强计经常被用于卫星在轨的姿态确认与修正,为提高其在轨磁场测量精度,提出了一种高精度的星载磁强计系统级标定方法。首先,引入了光学棱镜基准,完成了参照磁强计磁轴的正交性自校准。随后,利用二乘法完成了三轴零磁环境模拟... 详细信息

星载三轴磁强计经常被用于卫星在轨的姿态确认与修正,为提高其在轨磁场测量精度,提出了一种高精度的星载磁强计系统级标定方法。首先,引入了光学棱镜基准,完成了参照磁强计磁轴的正交性自校准。随后,利用二乘法完成了三轴零磁环境模拟系统线圈系数校准,再利用参照磁强计完成了三轴零磁环境模拟系统磁轴正交性标定,从而获得高精度的空间磁环境地面模拟系统。最后,利用三轴零磁环境模拟系统与卫星正交性对应关系,完成了星载磁强计的标定。试验结果表明:经过标定后,三轴零磁环境模拟系统非正交度优于0.01°,星载磁强计标定误差优于10 nT,为星载磁强计系统地面标定试验验证提供了新途径。

关键词：卫星控制姿态确定磁强计自校准装置棱镜

氮添加加剧了海南岛尖峰岭热带山地雨林次生林植物生长的磷限制

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生态学杂志 2024年第7期43卷 2102-2108页

作者：游慧敏查苏娜吴桂林陈德祥张涛旷远文吴建辉周璋中国林业科学研究院热带林业研究所海南尖峰岭森林生态系统国家野外科学观测研究站广州510520 南京林业大学南京210037 中国林业科学研究院热带林业研究所试验站海南尖峰572542 中国科学院华南植物园广州510520

人类活动改变了生态系统中氮(N)和磷(P)的有效性,正深刻影响着生态系统的养分循环。本研究以海南尖峰岭热带山地雨林原始林和次生林为对象,通过11年野外氮(N)、磷(P)和氮+磷(NP)添加实验,量化氮、磷添加对土壤和植物叶片N、P含量的影响... 详细信息

人类活动改变了生态系统中氮(N)和磷(P)的有效性,正深刻影响着生态系统的养分循环。本研究以海南尖峰岭热带山地雨林原始林和次生林为对象,通过11年野外氮(N)、磷(P)和氮+磷(NP)添加实验,量化氮、磷添加对土壤和植物叶片N、P含量的影响,探讨热带森林的养分限制格局。结果表明:N添加对原始林和次生林土壤和叶片N、P含量均无显著影响;P和NP添加显著提高了原始林和次生林土壤有效P含量,而对叶片N、P含量无显著影响;自然条件下原始林和次生林叶片N∶P均超过16,P与NP添加均显著降低了两种林型叶片N∶P;N添加显著增加了次生林叶片N∶P,而对原始林叶片N∶P影响不显著;次生林中土壤有效N和土壤有效P呈显著负相关,原始林中两者关系不显著,而两种林型中叶片N∶P均与土壤有效P呈显著负相关。上述研究结果表明:尖峰岭热带山地雨林原始林和次生林植物生长均受P限制,P添加可以有效缓解P限制;N添加加剧了热带山地雨林次生林的P限制作用。该研究为增进全球变化背景下的生态系统养分限制格局的了解提供重要的参考依据。

关键词：氮添加磷添加热带雨林营养元素限制氮磷比

Responses of soil CH_(4) fluxes to nitrogen addition in two tropical montane rainforests in southern China

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Forest Ecosystems 2022年第3期9卷 335-343页

作者： Fangtao Wu Changhui Peng Chuanyao Wang Huai chen Weiguo Liu Zhihao Liu Hui Wang Hong Li dexiang chen Yide Li Shirong Liu Center for Ecological Forecasting and Global Change College of ForestryNorthwest Agriculture and Forestry UniversityYangling712100China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau College of ForestryNorthwest Agriculture and Forestry UniversityYangling712100China Department of Biology Sciences Institute of Environment SciencesUniversity of Quebec at MontrealC.P.8888Succ.Centre-VilleMontrealQCH3C 3P8Canada chengdu Institute of Biology Chinese Academy of SciencesChengdu610041China School of Architecture and Urban Planning Chongqing UniversityChongqing400044China Jianfengling National Key Field Observation and Research Station for Forest Ecosystem Research Institute of Tropical ForestryChinese Academy of ForestryGuangzhou510520China Research Institute of Forest Ecology Environment and ProtectionChinese Academy of ForestryBeijing100091China

Background:Atmospheric nitrogen(N)deposition is projected to increase in the next few decades,which may have a marked impact on soil-atmosphere CH_(4) ***,the impacts of increased atmospheric N depositions on soil CH_(4) flux in tropical rainforests are still poorly *** January 2015 to December 2018,a field experiment was conducted in a primary tropical montane rainforest(PTMR)and a secondary tropical montane rainforest(STMR)in southern China to quantify the impact of N additions at four levels(N0:0 kg N⋅ha^(-1)⋅year^(-1);N25:25 kg N⋅ha^(-1)⋅year^(-1);N50:50 kg N⋅ha^(-1)⋅year^(-1);N100:100 kg N⋅ha^(-1)⋅year^(-1)on soil CH_(4) ***:Four years of measurements showed clear seasonal variations in CH_(4) flux in all treatment plots for both forest types(PTMR and STMR),with lower rates of soil CH_(4) uptake during the wet season and higher rates of soil CH_(4) uptake during the dry *** CH_(4) uptake rates were significantly and negatively correlated with both soil temperature and soil moisture for both forest *** CH_(4) uptake for the N0 plots from the PTMR and STMR soils were2.20 and1.98 kg N⋅ha^(-1)⋅year^(-1),*** the PTMR site,mean CH_(4) uptake compared with the N0 treatment was reduced by 19%,29%,and 36%for the N25,N50,and N100 treatments,*** the STMR site,mean CH_(4) uptake compared with the N0 treatment was reduced by 15%,18%,and 38%for the N25,N50,and N100 treatments,*** level N addition had a stronger inhibitory impact on soil CH_(4) uptake than did the low level N ***:Our data suggest that soil CH_(4) uptake in tropical rainforests is sensitive to N *** atmospheric N deposition continues to increase in the future,the soil CH_(4) sink strength of tropical rainforests may weaken further.

关键词： Atmospheric nitrogen deposition Greenhouse gases Soil CH_(4)flux Tropical rainforest

Optimal Scheduling of Regional Integrated Energy Systems Considering Hybrid Demand Response

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1208-1219页

作者： Ganyun Lyu Bin Cao dexiang Jia Nan Wang Jun Li Guangyu chen Department of Electrical Engineering Nanjing Institute of TechnologyNanjing 211167China State Grid Energy Research Institute Co. LTDBeijing 102209China State Grid Integrated Energy Service Group Co. LTDBeijing 100032China IEEE CSEE

Flexible load can optimize the load curve,which is an important means to promote renewable energy *** peculiarities of electricity,heat,cooling and gas loads are analyzed in this paper,considering the fuzzy degree of human perception for water temperature,and the characteristic model of hot water load is *** the fuzzy degree of human perception of ambient temperature,the characteristic model of cooling load is established by using PMV and PPD ***,considering four combinations of cut load,translatable load,transferable load and alternative load,and considering the coupling relationship of composite parts,different response models of load are established *** the minimum cost of the system,including operation and compensation costs as the objective function,the optimization scheduling model of the regional integrated energy system is established,and the Gurobi solver is used for simulation analysis to solve the optimal output and load response curve of each piece of *** results show that the load curve can be optimized,the flexible regulation ability of the regional integrated energy system can be enhanced,the energy loss of the system can be reduced,and the wind power consumption ability of the system can be increased by considering the integrated demand response.

关键词： Alternative load day ahead optimal scheduling integrated demand response PMV and PPD index regional integrated energy system

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党的文化领导力建设与国家治理现代化

湖南师范大学社会科学学报 2022年第6期51卷 18-25页

作者：陈德祥湖南师范大学马克思主义学院湖南长沙410081

党的文化领导力是党的领导力的重要组成部分,实质是文化的价值和功能在政党政治活动中的体现,关乎执政兴衰、国家发展与社会稳定.在国家治理现代化视域中,文化是国家治理的对象客体和工具手段,引领和支撑国家治理现代化;中国共产党是国... 详细信息

党的文化领导力是党的领导力的重要组成部分,实质是文化的价值和功能在政党政治活动中的体现,关乎执政兴衰、国家发展与社会稳定.在国家治理现代化视域中,文化是国家治理的对象客体和工具手段,引领和支撑国家治理现代化;中国共产党是国家治理的主体要素,党的领导是国家治理现代化的制度优势和本质规定.中国国家治理现代化就是中国共产党凝聚思想以求共识、运用科技赋能治理、融通文化创新理论、塑造价值达成文明的社会历史活动.思想凝聚力、科技创新力、文化建构力、价值塑造力成为党的文化领导力的主要方面和核心内容.新时代加强党的文化领导力建设需要建好主流意识形态以增强国家思想凝聚力,提升国民科学素养以增强党和国家科技创新力,融通各种文化资源以提升国家文化建构力,培育良好社会风尚以提升国家价值引领力.

关键词：中国共产党文化领导力国家治理现代化

Targeting epidermal Langerhans cells by epidermal powder immunization

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Cell Research 2002年第2期12卷 97-104页

作者： dexiang chen, LENDON G PAYNEPowderJect Vaccines, Inc. 585 Science Drive, Madison, WI 53711, USA PowderJect Vaccines Inc. 585 Science Drive Madison USA

Immune reactions to foreign or self-antigens lead to protective immunity and, sometimes, immune disorders such as allergies and autoimmune diseases. Antigen presenting cells （APC） including epidermal Langerhans cells （LCs） play an important role in the course and outcome of the immune reactions. Epidermal powder immunization （EPI） is a technology that offers a tool to manipulate the LCs and the potential to harness the immune reactions towards prevention and treatment of infectious diseases and immune disorders.

关键词： Langerhans cells dendritic cells vaccines epidermal immunization.

Temperature and substrate availability regulate soil respiration in the tropical mountain rainforests,Hainan Island,China

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Journal of Plant Ecology 2013年第5期6卷 325-334页

作者： Zhang Zhou Lai Jiang Enzai Du Huifeng Hu Yide Li dexiang chen Jingyun Fang Department of Ecology College of Urban and Environmental SciencesPeking UniversityBeijing 100871China School of Urban Planning and Design Shenzhen Graduate SchoolPeking UniversityShenzhen 518055China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China Research Institute of Tropical Forestry Chinese Academy of ForestryGuangzhou 510520China

Aims Tropical forest plays a key role in global C cycle;however,there are few studies on the C budget in the tropical rainforests in *** study aims to(i)reveal the seasonal patterns of total soil respiration(R_(T)),litter respiration(R_(L))and soil respiration without surface organic litter(R_(NL))in the primary and secondary Asian tropical mountain rainforests and(ii)quantify the effects of soil temperature,soil moisture and substrate availability on soil *** The seasonal dynamics of soil CO_(2) efflux was measured by an automatic chamber system(Li-8100),within the primary and secondary tropical mountain rainforests located at the Jianfengling National Reserve in Hainan Island,*** litter removal treatment was used to assess the contribution of litter to belowground CO_(2) *** Findings The annual R_(T) was higher in the primary forest(16.73±0.87 Mg C ha−1)than in the secondary forest(15.10±0.26 Mg C ha−1).The rates of R_(T),R_(NL) and R_(L) were all significantly higher in the hot and wet season(May–October)than those in the cool and dry season(November–April).Soil temperature at 5cm depth could explain 55–61%of the seasonal variation in R_(T),and the temperature sensitivity index(Q_(10))ranked by R_(L)(Q_(10)=3.39)>R_(T)(2.17)>R_(NL)(1.76)in the primary forest and by R_(L)(4.31)>R_(T)(1.86)>R_(NL)(1.58)in the secondary *** contribution of R_(L) to R_(T) was 22–23%,while litter input and R_(T) had 1 month time *** addition,the seasonal variation of R_(T) was mainly determined by soil temperature and substrate *** findings suggested that global warming and increased substrate availability are likely to cause considerable losses of soil C in the tropical forests.

关键词： soil respiration soil temperature litter tropical mountain rainforest

Biomass and carbon dynamics of a tropical mountain rain forest in China

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Science China(Life Sciences) 2010年第7期53卷 798-810页

作者： chen dexiang LI YiDe LIU HePing XU Han XIAO WenFa LUO TuShou ZHOU Zhang LIN MingXian Research Institute of Tropical Forestry Chinese Academy of ForestryGuangzhou 510520China Department of Physics Atmospheric Science and GeoscienceJackson State UniversityMS 39217USA Research Institute of Forest Ecology Environment and ProtectionChinese Academy of ForestryBeijing 100091China Department of Ecology College of Urban and Environmental SciencesPeking UniversityBeijing 100872China

Biometric inventories for 25 years,from 1983 to 2005,indicated that the Jianfengling tropical mountain rain forest in Hainan,China,was either a source or a modest sink of ***,this forest was a small carbon sink with an accumulation rate of(0.56±0.22) Mg C ha-1yr-1,integrated from the long-term measurement data of two plots(P9201 and P8302).These findings were similar to those for African and American rain forests((0.62±0.23) Mg C ha-1yr-1).The carbon density varied between(201.43±29.38) Mg C ha-1 and(229.16±39.2) Mg C ha-1,and averaged(214.17±32.42) Mg C ha-1 for plot *** P8302,however,varied between(223.95±45.92) Mg C ha-1 and(254.85±48.86) Mg C ha-1,and averaged(243.35±47.64) Mg C *** relationships were found between the strength of carbon sequestration and heavy rainstorms and dry *** and evapotranspiration are two major factors controlling carbon sequestration in the tropical mountain rain forest.

关键词： Jianfengling tropical mountain rain forest biomass carbon storage environmental determinants

Influence of sulfur on inclusion and pitting resistance of 316L stainless steel

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Baosteel Technical Research 2020年第3期14卷 31-38页

作者： chen dexiang QIANG Shaoming New Material Industry Innovation Center China Baowu Steel Group Co.Ltd.Shanghai 201999China Research Institute Baoshan Iron&Steel Co.Ltd.Shanghai 201999China

The effect of the sulfur content on the microstructure and inclusions of 316 L stainless steel was studied by optical microscopy,scanning electron microscopy,and image analysis,and the effect of sulfur on the pitting corrosion resistance of 316 L stainless steel was studied by conducting ferric chloride immersion test and plotting the electrochemical polarization *** results show that the added sulfur is mainly in the form of manganese sulfide inclusions in 316 L stainless *** increases in the sulfur content,the grade and percentage of the sulfide in the steel gradually increased,and its distribution became increasingly *** the sulfur content exceeded0.1%,the number of sulfide inclusions in the sample increased *** the sulfur content reached 0.199%,the sulfides in the steel were primarily in spindle form,and a large number of spindles were found to refine the grain size of 316 L stainless *** pitting corrosion weight loss rate of 316 L stainless steel increased with increases in the sulfur content,while the pitting potential gradually ***,the pitting potential of 316 L stainless steel rebounded when the sulfur content reached 0.199%,which may be related to the grain refinement of the test steel and requires further study.

关键词： stainless steel manganese sulfide pitting corrosion resistance pitting potential