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Methods of rapid orbit forecasting after maneuvers for geostationary satellites

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Science China(Physics,Mechanics & Astronomy) 2009年第3期52卷 333-338页

作者： YANG XuHai li ZhiGang FENG ChuGang GUO Ji shi Huli AI GuoXiang WU FengLei QIAO RongChuan National Time Service Center(NTSC) Chinese Academy of SciencesXi’an 710600China National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China Graduate University of Chinese Academy of Sciences Beijing 100049China Beijing Aerospace Control Center(BACC) Beijing 100094China

A geostationary(GEO) satellite may serve as a navigation satellite,but there is a problem that maneuvers frequently occur and the forces are difficult to *** on the technique of determining satellite orbits by transfer,a predicted orbit with high accuracy may be achieved by the method of statis-tical orbit determination in case of no maneuver *** predicted orbit will soon be invalid after the maneuver starts,and it takes a long time to get a valid orbit after the maneuver *** order to improve ephemeris usability,the method of rapid orbit forecasting after maneuvers is ***,GEO satellite movement is analyzed in case of maneuvers based on the observation from the orbit meas-urement system by *** when a GEO satellite is in the free status just after maneuvers,the short arc observation is used to forecast the *** is assumed that the common system bias and biases of each station are constant,which can be obtained from orbit determination with long arc *** this way,only 6 orbit elements would be solved by the method of statistical orbit determination,and the ephemeris with high accuracy may be soon *** orbit forecasting with short arc observation for SINOSAT-1 satellite shows that,with the tracking network available,the precision of the predicted orbit(RMS of O-C) can reach about 5 m with 15 min arc observation,and about 3 m with 30 min arc observation.

关键词： geostationary satellite satellite maneuver orbit forecasting

Simultaneous measurements of nonlinear refraction and nonlinear absorption using a 4f imaging system

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Science China(Technological Sciences) 2008年第9期51卷 1483-1490页

作者： li YunBo SONG Yinglin WANG YuXiao ZHANG XueRu SUN JiangQin YANG JunYi shi Guang WANG Yu School of Physical Science and Technology Suzhou UniversitySuzhou 215006China Department of Physics Harbin Institute of TechnologyHarbin 150001China

A method is reported to simultaneously measure the nonlinear absorption and re-fraction coefficients of materials using a nonlinear-imaging technique with a phase object. In this technique, the sign and magnitude of both the nonlinear absorption and refraction can be acquired conveniently from the analysis of three experiment images: the linear image, the nonlinear image and the image without sample. In order to validate our approach, we demonstrate this method for ZnSe at 532 nm where two-photon absorption is present and the nonlinear refractive index n2 is negative. The values of β (nonlinear absorption coefficient) and n2 we measured are very close to the values found in other literature.

关键词： nonlinear absorption nonlinear refraction 4f system phase object

Effect of Deep Cryogenic Treatment on Formation of Reversed Austenite in Super Martensitic Stainless Steel

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Journal of Iron and Steel Research International 2015年第5期22卷 451-456页

作者： shi-qi ZHENG Wen JIANG Xuan BAI Shao-hong li Kun-yu ZHAO Xin-kun ZHU Department of Materials Science and Engineering Kunming University of Science and Technology

The effect of deep cryogenic treatment on the formation of reversed austenite （RA） in super martensitic stainless steel was investigated. RA was found to form in steels without （A） and with （B） deep cryogenic treatment. The volume fraction of RA initially increased and then decreased with increasing tempering temperature over 550-- 750 ℃ for the two steels, which were quenched at 1050 ℃. In addition, for both with and without deep cryogenic treatment, the RA content reached a maximum value at 650 ℃ although the RA content in steel B was greater than that in steel A over the entire range of tempering temperatures. Furthermore, the hardness （HRC） of steel B was greater than that of steel A at tempering temperatures of 550--750 ℃. From these results, the basic mechanism for the formation of RA in steels A and B was determined to be Ni diffusion. However, there were more Ni enriched points, a lower degree of enrichment, and a shorter diffusion path in steel B. It needed to be noted that the shapes of the RA consisted of blocks and stripes in both steels. These shapes resulted because the RA redissolved and trans- formed to martensite along the martensitic lath boundaries when the tempering temperature was 650--750 ℃, and a portion of RA in the martensitie lath divided the originally wider martensitic laths into a number of thinner ones. In- terestingly, the RA redissolved more rapidly in steel B and consequently resulted in a stronger refining effect.

关键词： reversed austenite super martensitie stainless steel deep cryogenic treatment diffusion transformation

Microbial diversity and functionally distinct groups in produced water from the Daqing Oilfield,China

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Petroleum Science 2012年第4期9卷 469-484页

作者： li Hui Ai Mingqiang Han Siqin Guo Yanling li Nana shi Rongjiu Zeng Xiangling Leng Shengbing Zhao Jinyi liu Xiaobo Zhang Ying Key Laboratory of Pollution Ecology and Environment Engineering Institute of Applied EcologyChinese Academy of SciencesShenyangLiaoning 110016China Daqing Oilfield Co.Ltd. DaqingHeilongjiang 163414China

The microbial community structure and functionally distinct groups in three kinds of produced water samples from the shallow,mesothermic and low-salinity Daqing oil reservoir were systematically evaluated using both culture-dependent and culture-independent *** analysis of the 16S rRNA genes indicated that the bacterial library was dominated by Acinetobacter and Arcobacter and the archaeal community was dominated by Methanosaeta and *** isolated methanogens were closely related with Methanothermobacter thermautotrophicus and Methanoculleus *** fermentative bacteria were identified as Pseudomonas,Haloanaerobium,Alcalibacter,Arcobacter,and *** predominant nitrate-reducing bacteria fell within the genus *** dominant members of the cultured hydrocarbon-oxidizing bacteria were phylogenetically associated with Micrococcus,Pseudomonas,and *** of biosurfactants and biopolymer producing groups mainly yielded Pseudomonas,Bacillus,and Acenitobacter-related *** functional groups related to polymer degradation were also affiliated with Pseudomonas and *** from this study provide the fresh insight into the diversity of microbial communities in Daqing petroleum *** vast pool of functional strains retrieved in this study was presumed to include the promising strains that could be applied in microbial-enhanced oil recovery in future.

关键词： Petroleum microbiology 16S rRNA gene diversity methanogens bio-surfactants producing bacteria biopolymer-producing bacteria nitrate-reducing bacteria

New Insights into the Nitrogen Form Effect on Photosynthesis and Photorespiration

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Pedosphere 2007年第5期17卷 601-610页

作者： GUO shi-Wei ZHOU Yi GAO Ying-Xu li Yong SHEN Qi-Rong College of Resources and Environmental Sciences Nanjing Agricultural University Nanjing 210095 （China）

Under high light conditions, ammonium nutrition has a negative effect on plant growth. This suggests that the adverse effects of ammonium nutrition on plant growth may be related to carbon gain, photosynthesis, and photorespiration. However, there is no consistent evidence of a specific mechanism that could explain the plant growth reduction under ammonium supply. It is generally accepted that during the light reaction, a surplus of nicotinamide adenine dinucleotide hydrogen phosphate （NADPH） is produced, which is not completely used during the assimilation of CO2, Nitrate reduc- tion in the leaf represents an additional sink for NADPH that is not available to ammonium-grown plants. Nitrate and ammonium nutrition may use different pathways for NADPH consumption, which leads to differences in photosynthesis and photorespiration. The morphological （i.e., cell size, mesophyll thickness, and chloroplast volume） and enzymic （i.e., ribulose-1,5-bisphosphate carboxylase/oxygenase （Rubisco）, phosphoenolpyruvate carboxylase （PEPCase）, and glutamine synthetase/glutamate synthetase （GS/GOGAT）） differences that develop when plants are treated with either nitrate or ammonium nitrogen forms are related to photosynthesis and photorespiration. The differences in photorespiration rate for plants treated with nitrate or ammonium are related to the conversion of citrate to 2-oxoglutarate （2-OG） and photorespiratory CO2 refixation.

关键词： ammonium nitrate nitrogen form photorespiration photosynthesis

Recent advances of traditional Chinese medicine on the prevention and treatment of COVID-19

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Chinese Journal of Natural Medicines 2020年第12期18卷 881-889页

作者： DAI Yu-Jie WAN shi-Yao GONG Shuai-Shuai liU Jin-Cheng li Fang KOU Jun-Ping Jiangsu Key Laboratory of TCM Evaluation and Translational Research School of Traditional Chinese PharmacyDepartment of Pharmacology of Chinese Materia MedicaChina Pharmaceutical UniversityNanjing 211198China

Coronavirus disease-2019(COVID-19)is a new highly infectious disease caused by a novel ***,the number of new cases infected pneumonia in the world continues to increase,which has aroused great concern from the international *** present,there are no small-molecule specific anti-viral drugs for the *** high mortality rate seriously threatens human *** Chinese medicine(TCM)is a unique health resource in *** combination of TCM and Western medicine has played a positive and important role in combating COVID-19 in *** this review,through literature mining and analysis,it was found that TCM has the potential to prevent and treat the ***,the network pharmacological studies demonstrated that TCM played roles of anti-virus,anti-inflammation and immunoregulation in the management of COVID-19 via multiple components acting on multiple targets and multiple ***,clinical researches also confirmed the beneficial effects of TCM on the treatment of *** review may provide meaningful and useful information on further drug development of COVID-19 and other viral infectious diseases.

关键词： Novel coronavirus pneumonia Prescription of traditional Chinese medicine Single Chinese herb Active ingredients of traditional Chinese medicine Viral infection

Parzen Window Estimated Value Convergence of Density Function

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数学进展 2006年第5期35卷 638-640页

作者：贾天理 WANG shi-kun Department of Mathematics and Information Science Mianyang Normal University Mianyang Sichuan621000 P. R. China 不详

Many commonly known density functions can seldom fit the probability density function in real-world *** recent years,many researchers attempt to solve these difficulties. This article embarks from a new kind of point of view, regarding population whose classified symbol probability density function form was not known in advance,making use of various

关键词： Window lim

Satellite Clock Offset Determination and Prediction with Integrating Regional Satellite‐ground and Inter‐satellite Data

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Satellite Clock Offset Determination and Prediction with Int...

Identification of additional QTLs for flowering time by removing the effect of the maturity gene E1 in soybean

第五届中国卫星导航学术年会

作者： liu li shi Xin Tang Guifen Du Lan Zhu lingfeng Guo Rui Beijing Satellite Navigation Center Information Engineering University

ISBN: (纸本)9783642547393

Time synchronization between Satellites is the foundation for satellite navigation system,which is realized by satellite‐ground clock offset determination and ***,satellite clock offset determination and prediction is a key technique for satellite navigation *** present,precise time synchronization between satellites by inter‐satellite link and auto‐time synchronization is considered to be important development direction for navigation domain.A satellite clock offset determination and prediction method by integrating regional satellite‐ground observation data and inter‐satellite observation data is *** first introduce some common used methods for satellite clock determination,and then discuss the principle and data process model for satellite clock determination based on inter‐satellite link *** provide the method of Helmert variance components estimation to determine and predict satellite clock based on integrating satellite‐ground and inter‐satellite observation *** last,we analysis the performance for our method by using real observation data and simulation data,the result shows the method overcomes the defects of regional monitoring network and improves the precise of prediction form 8ns to 1.5ns for MEO satellite when the satellites can’t been *** method also increases the satellite clock data when the satellites can be observed,which can improved the precise and reliability for determination and prediction satellite clock offset.

关键词： Navigation satellite Time synchronization Inter‐satellite link Clock offset determination Clock offset prediction.

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Journal of Integrative Agriculture 2016年第1期15卷 42-49页

作者： LU Si-jia li Ying WANG Jia-lin NAN Hai-yang CAO Dong li Xiao-ming shi Dan-ning FANG Chao shi Xin-yi YUAN Xiao-hui Jun Abe liU Bao-hui KONG Fan-jiang Key Laboratory of Soybean Molecular Design Breeding Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Harbin 150081 P.R.China University of Chinese Academy of Sciences Beijing 100049 P.R. China State Key Laboratory of Tree Genetics and Breeding Northeast Forestry University Harbin 150040 P.R.China Research Faculty of Agriculture Hokkaido University Sapporo 060-8589 Japan

The adaptability of soybean to be grown at a wide range of latitudes is attributed to natural variation in the major genes and quantitative trait loci （QTLs） that control flowering time and maturity. Thus, the identification of genes controlling flowering time and maturity and the understanding of their molecular basis are critical for improving soybean productivity. However, due to the great effect of the major maturity gene E1 on flowering time, it is difficult to detect other small-effect QTLs. In this study, aiming to reduce the effect of the QTL, associated with the E1 gene, on the detection of other QTLs, we divided a population of 96 recombinant inbred lines （RILs） into two sub-populations： one with the E1 allele and another with the elns allele. Compared with the results of using all 96 recombinant inbred lines, additional QTLs for flowering time were identified in the sub-populations, two （qFT-B1 and qFT-H） in RILs with the E1 allele and one （qFT-J-2） in the RILs with the elnl allele, respectively. The three QTLs, qFT-B1, qFT-H and qFT-J-2 were true QTLs and played an important role in the regulation of growth period. Our data provides valuable information for the genetic mapping and gene cloning of traits controlling flowering time and maturity and will help a better understanding of the mechanism of photoperiod-regulated flowering and molecular breeding in soybean.

关键词： multiple QTL model (MQM) mixed model-based composite interval mapping (MCIM) photoperiod maturity,productivity