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A simplex method for the orbit determination of maneuvering satellites

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Science China(Physics,Mechanics & Astronomy) 2018年第2期61卷 49-55页

作者： jianrong chen JunFeng Li XiJing Wang Jun Zhu DanNa Wang School of Aerospace Engineering Tsinghua University Beijing 100084 China State Key Laboratory of Astronautic Dynamics Xi'an 710043 China Shanghai Institute of Spaceflight Control Technology Shanghai 201108 China

A simplex method of orbit determination （SMOD） is presented to solve the problem of orbit determination for maneuvering satellites subject to small and continuous thrust. The objective function is established as the sum of the nth powers of the observation errors based on global positioning satellite （GPS） data. The convergence behavior of the proposed method is analyzed using a range of initial orbital parameter errors and n values to ensure the rapid and accurate convergence of the SMOD. For an uncontrolled satellite, the orbit obtained by the SMOD provides a position error compared with GPS data that is commensurate with that obtained by the least squares technique. For low Earth orbit satellite control, the precision of the acceleration produced by a small pulse thrust is less than 0.1% compared with the calibrated value. The orbit obtained by the SMOD is also compared with weak GPS data for a geostationary Earth orbit satellite over several days. The results show that the position accuracy is within 12.0 m. The working efficiency of the electric propulsion is about 67% compared with the designed value. The analyses provide the guidance for subsequent satellite control. The method is suitable for orbit determination of maneuvering satellites subject to small and continuous thrust.

关键词： simplex method orbit determination electric propulsion orbit control

Biochar-based materials and their applications in removal of organic contaminants from wastewater:state-of-the-art review

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Biochar 2019年第1期1卷 45-73页

作者： Qiang Huang Shuang Song Zhe chen Baowei Hu jianrong chen Xiangke Wang MOE Key Lab of Resources and Environmental System Optimization College of Environmental Science and EngineeringNorth China Electric Power UniversityBeijing 102206People’s Republic of China School of Life Science Shaoxing UniversityHuancheng West Road 508Shaoxing 312000People’s Republic of China College of Geography and Environmental Science Zhejiang Normal UniversityJinhua 321004People’s Republic of China

As a class of famous carbon materials,biochars(BCs)and their derivative materials with excellent physicochemical properties and diversified functionalities present great potential in wastewater treatment *** review focuses on the latest development in reported biochar-based materials as superior adsorbents or catalysts for removing harmful organic contaminants from *** construction and properties of biochar-based materials are briefly introduced at the *** one of the major factors affecting the properties of BCs,the wide diversity of feedstocks,such as agricultural and forest residues,industrial by-products as well as municipal wastes,endows BCs different chemical compositions and *** and herbaceous BCs usually have higher carbon contents,larger surface areas and strong aromaticity,which is in favor of the organic contaminant *** by the desire of more cost-effective materials,several types of biochar-based hybrid materials,such as magnetic BC composites(MBC),nanometal/nanometallic oxides/hydroxide BC composites and layered nanomaterial-coated BCs,as well as physically/chemically activated BCs,have also been *** the help of foreign materials,these types of hybrid BCs have excellent capacities to remove a wide range of organic contaminants,including organic dyestuff,phenols and chemical intermediates,as well as pharmaceutically active compounds,from aquatic *** on the different types of biochar-based materials,organic contaminants can be removed by different mechanisms,such as physical adsorption,electrostatic interaction,π-πinteraction and Fenton process,as well as photocatalytic *** summary,the low cost,tunable surface chemistry and excellent physical-chemical properties of BCs allow it to be a potential material in organic contaminant *** combination of BCs with foreign materials endows BCs more functionalities and broader development *** the urge

关键词： Biochar-based materials Water purification Organic contaminants Catalytic degradation Adsorption

Identification of Potential Sites of Debris Flows in the Upper Min River Drainage,Following Environmental Changes Caused by the Wenchuan Earthquake

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Journal of Mountain Science 2010年第3期7卷 255-263页

作者： LIU Jinfeng YOU Yong chen Xingchang FAN jianrong Key Laboratory of Mountain Surface Process and Hazards Chinese Academy of Sciences Chengdu 610041 P.R. ChinaInstitute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 P.R. China

The Wenchuan earthquake caused numerous landslides and collapses that provide abundant unconsolidated material for future mobilization as debris *** flows will be very active and cause considerable damage for some time in the affected *** of environmental changes related to the earthquake,many potentially dangerous debris flow gullies have yet to be *** paper selects the upper Min River from Yinxiu to Wenchuan as the study area,interprets the unconsolidated deposits,and discusses their relationship to distance from the ***,applying that information and the values of other factors relating to debris flow occurrence,the locations of potential debris flows are analyzed by multi-factor comprehensive identification and rapid *** multi-factor comprehensive identification employs fuzzy matter-element extension *** volume of unconsolidated material in the study area is about 3.28 × 108 *** to the analysis by multi-factor comprehensive identification,47 gullies have a high probability for potential debris flow,8 gullies have a moderate probability,and 1 gully has a low probability.

关键词： Wenchuan earthquake unconsolidatedmaterial potential debris flow identification

Precise Orbit Determination for BeiDou Satellites during Eclipse Seasons

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Precise Orbit Determination for BeiDou Satellites during Ecl...

Precise regulation of pyrrole-type single-atom Mn-N4 sites for superior pH-universal oxygen reduction

第五届中国卫星导航学术年会

作者： Zhu Jun chen jianrong Zeng Guang Li Jie Wang Jiasong State Key Laboratory of Astronautic Dynamics Xi’an Satellite Control Center

ISBN: (纸本)9783642547393

During the eclipse seasons, BeiDou IGSO/MEO satellites perform attitude maneuvers from yaw‐steering to yaw‐fixed, while the nominal yaw‐angle is fixed to zero. Unfortunately, different levels of the orbit accuracy degradations in the Precise Orbit Determination （POD） process occur in this period. In this paper, a reduce‐dynamic orbital model with additional pseudo‐stochastic parameters is introduced to improve the orbit quality. The geometrical corrections in observations and the force variations related to attitude are modeled and investigated. The pseudo‐stochastic orbit modeling techniques are applied for absorbing effects of the mis‐modeled part of the attitude maneuvers. The POD results indicate a significantly improved performance of orbit with appropriate pseudo‐stochastic parameters for BeiDou satellites during eclipse seasons.

关键词： Precise Orbit Determination (POD). BeiDou navigation satellite System (BDS). Solar Radiation Pressure (SRP). eclipse seasons.

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Carbon Energy 2021年第6期3卷 856-865页

作者： Lei Yan Liyan Xie Xi-Lin Wu Mengying Qian jianrong chen Yijun Zhong Yong Hu Department of Chemistry Key Laboratory of the Ministry of Education for Advanced Catalysis MaterialsZhejiang Normal UniversityJinhuaZhejiangChina College of Geography and Environmental Science Zhejiang Normal UniversityJinhuaChina Hangzhou Institute of Advanced Studies Zhejiang Normal UniversityHangzhouZhejiangChina

The study of atomically dispersed metal-nitrogen electrocatalysts is still limited in terms of understanding their catalytic mechanism because of the inability to precisely regulate the coordination number and type of N in combination with the metal *** by the high catalytic activity and selectivity of natural enzymes,herein,we have designed and fabricated ultrathin carbon nanosheet-supported Mn single-atom catalysts(SACs)with a precise pyrrole-type Mn-N4(PT-MnN4)configuration using a bio-mimicking *** PT-MnN4 SACs display outstanding oxygen reduction reaction(ORR)activity,with a half-wave potential(E_(1/2))of 0.88 V(*** hydrogen electrode[RHE])and extremely high stability in alkaline ***,superior ORR activities are also obtained,E_(1/2) of 0.73 V and 0.63 V in acid and neutral electrolytes,respectively,indicating the efficient pH-universal ORR *** assembled zinc-air battery using the PT-MnN4 SACs as air cathodes exhibits a high peak power density(175 mW cm^(−2))and long-term stability up to 150 h,implying its promising application in metal-air *** study has paved the way toward the rational design and precise regulation of single-atom electrocatalysts.

关键词： oxygen reduction reaction pH-universal pyrrole-type N single-atom catalysts Zn-air batteries

Review of China’s Energy Policy in 2022

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China Oil & Gas 2023年第1期30卷 9-16页

作者： Zhang Pengcheng chen jianrong CNPC Economics&Technology Research Institute

2022 has seen continuous release of energy *** by changes in domestic and international situations such as the COVID-19 pandemic,the Ukraine crisis,the European energy crisis,the China-US game,and climate change,Chinese central government has attached great importance to energy *** 20th National Congress of the Communist Party of China and the Central Economic Work Conference made important instructions on the development of China’s energy,which reflect the systematicness and synergy of China’s energy security concept.A series of“14th Five-Year Plan”and medium to long-term special energy development plans have been successively ***“Dual-Carbon”1+N policy system has been basically *** energy field is of paramount importance to achieving carbon peak and carbon neutrality;thus,reform and protection policies have been intensively released,and the construction of a national unified energy market has made great progress,making overall energy security and green development become the main policy *** oil and gas companies,opportunities outweigh *** should follow the national policies,make good use of resource and technological advantages,continue to consolidate the main business of oil and gas production,develop emerging businesses and accelerate green,low-carbon transformation.

关键词： companies policy attached

Application of biochar-based photocatalysts for adsorption-(photo)degradation/reduction of environmental contaminants:mechanism,challenges and perspective

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Biochar 2022年第1期4卷 436-459页

作者： Yin Lu Yawen Cai Sai Zhang Li Zhuang Baowei Hu Suhua Wang jianrong chen Xiangke Wang Key Laboratory of Pollution Exposure and Health Intervention of Zhejiang Province College of Biological and Environment EngineeringZhejiang Shuren UniversityHangzhou 310015People’s Republic of China School of Life Science Shaoxing UniversityShaoxing 312000People’s Republic of China College of Environmental Science and Technology North China Electric Power UniversityBeijing 102206People’s Republic of China School of Environmental Science and Engineering Guangdong University of Petrochemical TechnologyMaoming 525000People’s Republic of China College of Geography and Environmental Science Zhejiang Normal UniversityJinhua 321004People’s Republic of China

The fast increase of population results in the quick development of industry and *** amounts of contaminants such as metal ions and organic contaminants are released into the natural environment,posing a risk to human health and causing environment ecosystem *** efficient elimination of contaminants from aqueous solutions,photocatalytic degradation of organic pollutants or the in-situ solidification/immobilization of heavy metal ions in solid phases are the most suitable strategies to decontaminate the *** and biochar-based composites have attracted multidisciplinary interests especially in environmental pollution management because of their porous structures,large amounts of functional groups,high adsorption capacities and photocatalysis *** this review,the application of biochar and biochar-based composites as adsorbents and/or catalysts for the adsorption of different contaminants,adsorption-photodegradation of organic pollutants,and adsorption-(photo)reduction of metal ions are summarized,and the mechanism was discussed from advanced spectroscopy analysis and DFT calculation in *** doping of metal or metal oxides is the main strategy to narrow the band gap,to increase the generation and separation of photogenerated e−-h+pairs,to produce more superoxide radicals(·O_(2)^(−))and hydroxyl radicals(·OH),to enhance the visible light absorption and to increase photocatalysis performance,which dominate the photocatalytic degradation of organic pollutants and(photo)reduction of high valent metals to low valent *** biochar-based composites are environmentally friendly materials,which are promising candidates in environmental pollution *** challenge and perspective for biochar-based catalysts are provided in the end.

关键词： Biochar-based composites Adsorption Photocatalytic degradation Photocatalytic reduction Environmental pollutants

Analysis on Policies of Oil and Gas in China

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China Oil & Gas 2018年第3期25卷 5-12页

作者： Jiang He chen jianrong CNPC Economics & Technology Research Institute

The Government has actively introduced oil and gas policies to promote the sustainable and healthy development of the industry it, 2017. The purposes of such policies are： to accelerate the reform of mineral resource royalties and advance the competitive transfer of mining rights; to promote the reform of the natural gas price, introduce cost supervision on long-distance natural gas pipeline enterprises in the area of gas pipeline transportation, and strengthen the regulation qf the distribution price; to liberalize the import qf crude oil in an orderly manner, increase the allowable volume of non-state trading crude oil imports, strengthen the supervision and periodically pause the approval of the right to use imported crude oil; and to enhance environmental protection.

关键词： Royalty Reform Price Crude oil import Environmental protection tax

ADSORPTION OF GALLIUM WITH N_503LEVEXTREL RESIN

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中国有色金属学会会刊：英文版 1994年第3期4卷 36-40页

作者： chen, jianrong Hu, Jianhua Peng, Chaoqun(Department of Chemistry,Zhe jiang Normal University,Jinhua 32100 4)

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关键词： gallium adsorption N503 levextrel resin