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Orbit determination for geostationary satellites with the combination of transfer ranging and pseudorange data

Science china(Physics,mechanics & Astronomy) 2010年第9期53卷 1746-1754页

作者： GUO Rui1,2,3,4,hu XiaoGong2,4,LIU Li1,WU XiaoLi1,huANG Yong2,4 & HE Feng1 1 beijing Global Information Application and Development Center,beijing 100094,china 2 Shanghai Astronomical Observatory,chinese academy of sciences,Shanghai 200030,china 3 Graduate University of chinese academy of sciences,beijing 100049,china 4 Space Navigation and Positioning Technology,Laboratory of Shanghai Municipal,Shanghai 200030,china beijing Global Information Application and Development Center Beijing China chinese academy of sciences Shanghai Astronomical Observatory Shanghai China (GRID:grid.9227.e) (ISNI:***) Graduate University of chinese academy of sciences Beijing China (GRID:grid.458514.9) Laboratory of Shanghai Municipal Space Navigation and Positioning Technology Shanghai China (GRID:grid.458514.9) chinese academy of sciences Shanghai Astronomical Observatory Shanghai China (GRID:grid.9227.e) (ISNI:***) Laboratory of Shanghai Municipal Space Navigation and Positioning Technology Shanghai China (GRID:grid.9227.e) beijing Global Information Application and Development Center Beijing China (GRID:grid.9227.e)

Geostationary satellites(GEOs) play a significant role in the regional satellite navigation *** experiments show that the clock corrections could be mitigated through a single strategy or double differencing strategies for a navigation constellation,but for the mode of individual GEO orbit determination,high precision orbit and clock correction could not be obtained in the orbit determination based on the pseudorange data.A new GEO combined precise orbit determination(POD) strategy is studied in this paper,which combines pseudorange data and C-band transfer ranging *** strategy overcomes the deficiency of C-band transfer ranging caused by limited stations and tracking time *** the combination of transfer ranging and pseudorange data,clock corrections between the GEO and the stations can be estimated simultaneously along with orbital parameters,maintaining self-consistency between the satellite ephemeris and clock correction *** error covariance analysis is conducted to illuminate the contributions from the transfer ranging data and the psudoranging *** data collected for a chinese GEO satellite with 3 C-band transfer ranging stations and 4 L-band pseudorange tracking stations,POD experiments indicate that a meter-level accuracy is *** root-mean-square(RMS) of the post-fit C-band ranging data is about 0.203 m,and the RMS of the post-fit pseudorange is 0.408 *** component errors of the POD experiments are independently evaluated with the satellite laser ranging(SLR) data from a station in beijing,with the residual RMS of 0.076 *** SLR evaluation also suggests that for 2-h orbital predication,the predicted radial error is about 0.404 m,and the clock correction error is about 1.38 *** for the combination of one C-band transfer ranging station and 4 pseudorange stations,POD is able to achieve a reasonable accuracy with the radial error of 0.280 m and the 2-h predicted radial error of 0.888 *** syn

关键词： satellite navigation precise orbit determination pseudorange equipment ranging delay GEO SLR

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The flhDC gene affects motility and biofilm formation in Yersinia pseudotuberculosis

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Science china(Life sciences) 2007年第6期50卷 814-821页

作者： WANG Yao1, DING LiSha1,2, hu YangBo1,2, ZHANG Yong1,2, YANG BaoYu1 & CHEN ShiYun1 1 Wuhan Institute of Virology, chinese academy of sciences, Wuhan 430071, china 2 Graduate University of chinese academy of sciences, beijing 100049, china Wuhan Institute of Virology Chinese Academy of Sciences Wuhan 430071 China

The flagella master regulatory gene flhDC of Yersinia pseudotuberculosis serotype III (YPIII) was mutated by deleting the middle region; replaced by a tetracycline resistant gene,; the subsequent mutant strain named YPIIIΔflhDC was obtained. Swimming assay showed that the swimming motility of the mutant strain was completely abolished. The promoter region of the flagella second-class regulatory gene fliA was fused with the lux box,; was conjugated with the mutant; the parent strains respectively for the first cross. LUCY assay result demonstrated that flhDC regulated the expression of fliA in YPIII as reported in E. coli. Biofilm formation of the mutant strain on abiotic; biotic surfaces was observed; quantified. The results showed that mutation of flhDC decreased biofilm formation on both abiotic; biotic surfaces,; abated the infection on Caenorhabdtis elegans. Our results suggest that mutation of the flagella master regulatory gene flhDC not only abolished the swimming motility, but also affected biofilm formation of YPIII on different surfaces. The new function of flhDC identified in this study provides a novel viewpoint for the control of bacterial biofilm formation.

关键词： Yersinia pseudotuberculosis, flhDC, motility, biofilm

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Preparation and antibacterial activity of aromatic derivatives of β-aminopropionic and γ-aminobutyric acid

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chinese Journal of Chemistry 1997年第4期15卷 366-370页

作者： GUAN,Jing-Qu hu,Zun-Ju ZOU,Zhi-Chen WU,Zhi-GuangDepartment of Chemistry,Shandong Teachers’ University,Jinan,Shandong 350014,china Institute of Photographic Chemistry,chinese academy of sciences,beijing 100101,china Department of Chemistry Shandong Teachers' University Jinan Shandong 250014 China Institute of Photographic Chemistry Chinese Academy of Sciences Beijing 100101 China

Ten aromatic derivatives of β-aminopropionic acid and γ-aminobutyric acid were *** compositions and structures were identified by elemental analysis,IR,and 1H *** have been examined for their antibacterial action against Staphylococcua aurens and Escherichia *** compounds showed higher activity than the aromatic derivatives of ct-amino acid which were reported *** general conclusion to be drawn is that the distance between amino and carboxylic group in these molecules could affect their antibacterial ***,those compounds with p-methyl substituent in phenyl ring exhibit higher activity than the others,and all the compounds exhibit higher activity against Escherichia coli and against Staphylococcua aureus.

关键词： Antibacterial agent aromatic derivatives β-aminopropionic acid γ-aminobutyric acid

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Very high upper critical fields of F-doped Fe-based layered superconductors NdO_(0.88)F_(0.12)FeAs and CeO_(0.88)F_(0.12)FeAs

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Science china(Physics,mechanics & Astronomy) 2008年第6期51卷 715-718页

作者： WU Dan, LI Zheng, SU ShaoKui, DONG Jing, LI Gang, hu WanZheng, ZHENG Ping, CHEN GenFu, LUO JianLin & WANG NanLin Institute of Physics, chinese academy of sciences, beijing 100190, china Institute of Physics Chinese Academy of Sciences Beijing China

Using the solid state reaction method, we have synthesized the polycrystalline F-doped NdO0.88F0.12FeAs and CeO0.88F0.12FeAs with the superconducting transition temperatures at about 48 and 40 K, respectively. To obtain the upper critical field Hc2 of Nd(Ce)O0.88F0.12FeAs samples, we measured the electrical resistivity under magnetic field up to 14 T. Based on the Werthamer-Helfand-Hohenberg (WHH) rela-tion together with the Hc2(T) curves in a relatively high field, we estimated that these superconductors have a rather high upper critical field of about 115 T for Nd-based and 107 T for Ce-based samples, indicating the similarities between these ReO1-xFxFeAs (Re = rare earth element) superconductors and high Tc cuprate su-perconductors.

关键词： upper critical field Fe-based superconductor

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Investigation on Pasting Characteristics of Spring-sown chinese Bread Wheats

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Agricultural sciences in china 2002年第7期1卷 720-724页

作者： ZHANG Yong and HE Zhong-hu(’ Institute of Crop Breeding and Cultivation /National Wheat Improvement Center, chinese academy of Agriculture sciences, beijing 100081 , P.R. china CIMMYT-china Office, chinese academy of Agricultural sciences ,beijing 100081 , P.R. china) Institute of Crop Breeding and Cultivation/National Wheat Improvement Center Chinese Academy of Agriculture Sciences Beijing 100081 P. R . China Institute of Crop Breeding and Cultivation/National Wheat Improvement Center Chinese Academy of Agriculture Sciences Beijing 100081 P. R . China CIMMYT-china Office Chinese Academy of Agricultural Sciences Beijing 100081P.R .China

Forty-seven spring wheat Triticumaestivum cultivars and advanced lines from spring-sown spring wheat regions, at twelve locations in 1998 and 1999, were used to investigate pasting properties of chinese spring wheats. Starch pasting properties were closely associated with noodle quality. Significant differences were observed for all pasting characteristics. Samples collected from Harbin, Shenyang, beijing, Ba-meng, Yongning, and Urumqi had better pasting quality than those from other locations. Genotype, environment, and genotype by environment interaction had large effects on all pasting characteristics. Significant correlations among pasting characteristics were observed and peak viscosity was considered the most important pasting characteristics.

关键词： Triticum aestivum Pasting characteristics Noodle quality Genotype and environment interaction

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Changes in extreme high temperature warning indicators over china under different global warming levels

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Science china Earth sciences 2024年第6期67卷 1895-1909页

作者： Yuxia ZHANG Ying SUN Ting hu chinese academy of Meteorological sciences Beijing 100081China National Climate Center Laboratory for Climate StudiesChina Meteorological AdministrationBeijing 100081China

High temperature warning indicators play a pivotal role in meteorological departments,serving as crucial criteria for issuing warnings that guide both social production and daily *** their importance,limited studies have explored the relationship between different global warming levels and changes in high temperature warning *** this study,we analyze data from 2,419 meteorological stations over china and utilize the Coupled Model Intercomparison Project Phase 6(CMIP6)models to examine historical changes in high temperature warning indicators used by the china Meteorological *** evaluate model performance and estimate future changes in these indicators using an annual cycle bias correction *** results indicate that since 1961,the number of high temperature days(TX35d and TX40d)and length of season(TX40d and TX40l)with daily maximum temperature reaching or exceeding 35℃ and 40℃ have increased over *** intensity of high temperatures(TXx)has strengthened and the geographical extent affected by high temperatures has *** 2022,the occurrence of 40℃ high temperatures surges,with Eastern china experiencing a two-day increase in TX40d and an extended seasonal length in TX40l by over five *** CMIP6 models have underestimated the high temperature indictors associated with 35℃ during historical periods,notable difference is not observed between the models and observations for TX40d and TX40l,given their rare ***,future projections,after bias correction,indicate that the increasing trends for 35℃ and 40℃ high temperature days and length of season become more pronounced than the raw projection,suggesting a more severe increase than that anticipated *** global warming intensifies,the high temperature days and length of season are projected to increase non-linearly,while the intensity of high temperatures is expected to increase *** every 1℃ increase in global temperature,the intensity is

关键词： Extreme high temperatures Meteorological warning CMIP6 Global warming levels Future projection

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Coupled conditional nonlinear optimal perturbations and their application to ENSO ensemble forecasts

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Science china Earth sciences 2024年第3期67卷 826-842页

作者： Wansuo DUAN Lei hu Rong FENG LASG Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of chinese academy of sciences Beijing 100049China

Limitations are existed in current ensemble forecasting initial perturbation methods for describing the interactions among various spheres of the Earth system. In this study, a new method is proposed, namely, the coupled conditional nonlinear optimal perturbation(C-CNOP) method, which incorporates multisphere interactions much appropriately. The El Nino-Southern Oscillation(ENSO) is a typical ocean-atmosphere “coupling”(or “interaction”) phenomenon. The C-CNOP method is applied to ensemble forecasting of ENSO. It is demonstrated that the C-CNOP method can generate coupled initial perturbations(CPs) that appropriately consider initial ocean-atmosphere coupling uncertainty for ENSO ensemble forecasts. Results reveal that the CPs effectively improve the ability of ENSO ensemble-mean forecasts in both temporal variability of Nio3.4 sea surface temperature anomalies(SSTAs) and spatial variability of ENSO mature-phase SSTAs. Notably, despite the weakest ocean-atmosphere coupling strength in the tropical Pacific occurring during the boreal spring and summer, CPs still capture the uncertainties of this weak coupling when ENSO predictions are initialized at these seasons. This performance of CPs significantly suppresses the rapid increase of ENSO prediction errors due to the high ocean-atmosphere coupling instability during these seasons, and thus effectively extends the lead time of skillful ENSO forecasting. Hence, the C-CNOP method is a suitable initial perturbation approach for ENSO ensemble forecast that can describe initial ocean-atmosphere coupling uncertainty. It is expected that the CCNOP method plays a significant role in predictions of other high-impact climate phenomena, and even future Earth system predictions.

关键词： Ensemble forecast Multisphere interaction Initial perturbations ENSO

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Ethylene oligomerization by novel iron(Ⅱ) diimine complexes/MAO

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chinese Science Bulletin 2002年第19期47卷 1616-1618页

作者： WANG Hang, YAN Weidong, JIANG Tao, LIU Binbin, XU Wenqing, MA Jianjiang & hu YouliangState Key Laboratory of Engineering Plastics, Center for Molecular Science, Institute of Chemistry, chinese academy of sciences, beijing 100080, china Graduate Student of State Key Lab. of Eng. Plastics Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China Grad. Student chinese Acad. of Sci. Beijing 100039 China Inst. of Polymer Science/Engineering School of Chemical Engineering Hebei University of Technology Tianjin 300130 China Dept. of Petrochemical Engineering Daqing Petroleum Institute Anda 151400 China Res. Inst. Dushanzi Petrochem. Co. PetroChina Xinjiang 833600 China

Two novel Fe(Ⅱ) diimine complexes have been synthesized. In combination with MAO, they generate active catalytic systems that oligomerize ethylene with both high catalytic activity and high selectivity for a-olefins. The effects of substituents on the aryl ring, reaction temperatures and molar ratios of Al/Fe on catalytic activity and product distribution are studied.

关键词： late-transition-metal catalysts ethylene oligomerization α-olefin.

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Investigation on Paste Property of chinese Bread Wheat Varieties

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Agricultural sciences in china 2002年第1期1卷 45-49页

作者： YAN Jun, ZHANG Yong and HE Zhong-hu( Institute of Crop Breeding and Cultivation , chinese academy of Agricultural sciences , beijing 100081 CIMMYT china Office, C/O chinese academy of Agricultural sciences, beijing 100081) Institute of Crop Breeding and Cultivation Chinese Academy of Agricultural Sciences Beijing 100081 Institute of Crop Breeding and Cultivation Chinese Academy of Agricultural Sciences Beijing 100081 CIMMYT china Office C/O Chinese Academy of Agricultural Sciences Beijing 100081

Starch viscosity is closely associated with noodle quality. RVA(rapid viscosity analyzer) was used to investigate the paste property of leading chinese wheat varieties arid 38 Australian wheat lines. Results showed that significant variability for RVA parameters was observed among chinese wheat varieties, particularly among spring wheat varieties. In general, Australia wheat lines performed better paste characters than that of chinese winter wheats. Genotype (G), environment (E) and genotype by environment (G×E) interaction affected all paste traits. Correlation analysis indicated that peak viscosity correlated highly and significantly with viscosity, breakdown, setback, final viscosity, peak time, and falling number(r = 0.56-0.93, Phuai Valley.

关键词： T. aestivum Bread wheat Paste traits RVA Noodle quality

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A draft sequence of the rice (Oryza sativa ssp. indica) genome

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chinese Science Bulletin 2001年第23期46卷 1937-1942页

作者： YU Jun, hu Songnian, WANG Jun,LI Songgang WONG Ka-Shu Gane, LIU Bin,DENG Yajun, DAI Li, ZHOU Yan,ZHANG Xiuqing, CAO Mengliang, LIU Jing,SUN Jiandong , TANG Jiabin, CHEN Yanjiong,huANG Xiaobing, LIN Wei, YE Chen, TONG Wei,CONG Lijuan, GENG Jianing, HAN Yujun, LI Lin,LI Wei, hu Guangqiang, huANG Xiangang,LI Wenjie, LI Jian, LIU Zhanwei, LI Long,LIU Jianping, Ql Qiuhui, LIU Jinsong, LI Li,WANG Xuegang, LU Hong, WU Tingling,Zhu Miao, Nl Peixiang, HAN hua, DONG Wei,REN Xiaoyu, FENG Xiaoli, GUI Peng,LI Xianran, WANG Hao, XU Xin, ZHAI Wenxue,XU Zhao, ZHANG Jinsong, HE Sijie,ZHANG Jianguo, XU Jichen, ZHANG Kunlin,ZHENG Xianwu, DONG Jianhai, ZENG Wanyong,TAO Lin, CHEN Xuewei, HE Jun, LIU Daofeng,TIAN Wei, TIAN Chaoguang, XIA Hongai,LI Gang, GAO hui, LI Ping, CHEN Wei ,WANG Xudong, ZHANG Yong, hu Jianfei,WANG Jing, LIU Song, YANG Jian,ZHANG Guangyu, XIONG Yuqing, LI Zhijie,MAO Long, ZHOU Chengshu, Zhu Zhen,CHEN Runsheng, HAO Bailin,ZHENG Weimou, CHEN Shouyi, QUO Wei,LI Guojie, LIU Siqi, huANG Guyang,TAO Ming, WANG Jian, Zhu Lihuang,YUAN Longping& YANG huanmingbeijing Genomics Institute/Center of Genomics & Bioinformatics, chinese academy of sciences, beijing 101300, china Hangzhou Genomics Institute/Institute of Bioinformatics of Zhejiang University/Key Laboratory of Bioinformatics of Zhejiang Province, Hangzhou 310007, china Institute of Genetics, chinese academy of sciences, beijing 100101, china National Hybrid Rice R & D Center, Changsha 410125, china Laboratory of Bioinformatics, Institute of Biophysics, chinese academy of sciences, beijing 100101, china College of Life sciences, Peking University, beijing 100871, china Institute of Theoretical Physics, chinese academy of sciences, beijing 1Q0080, china Digital china Ltd., beijing 100080, china Institute of Computing Technology, chinese academy of sciences, beijing 100080, china Medical College, Xi’an Jiaotong University, Xi’an 710061, chinaThese authors contributed equally to this work.Corresponding author.Corresponden beijing Genomics Institute/Center of Genomics & Bioinformatics Chinese Academy of Sciences Beijing China Hangzhou Genomics Institute/Institute of Bioinformatics of Zhejiang University/Key Laboratory of Bioinformatics of Zhejiang Province Hangzhou China College of Life sciences Peking University Beijing China Medical College Xi’an Jiaotong University Xi’an China Institute of Genetics Chinese Academy of Sciences Beijing China Laboratory of Bioinformatics Institute of Biophysics Chinese Academy of Sciences Beijing China National Hybrid Rice R & D Center Changsha China Institute of Theoretical Physics Chinese Academy of Sciences Beijing China Digital china Ltd. Beijing China Institute of Computing Technology Chinese Academy of Sciences Beijing China

The sequence of the rice genome holds fundamental information for its biology, including physiology, genetics, development, and evolution, as well as information on many beneficial phenotypes of economic significance. Using a "whole genome shotgun" approach, we have pro-duced a draft rice genome sequence of Oryza sativa ssp. in-dica, the major crop rice subspecies in china and many other regions of Asia. The draft genome sequence is constructed from over 4.3 million successful sequencing traces with an accumulative total length of 2214.9 Mb. The initial assembly of the non-redundant sequences reached 409.76 Mb in length, based on 3.30 million successful sequencing traces with a total length of 1797.4 Mb from an indica variant cultivar 93-11, giving an estimated coverage of 95.29% of the rice genome with an average base accuracy of higher than 99%. The coverage of the draft sequence, the randomness of the sequence distribution, and the consistency of BIG-ASSEM-BLER, a custom-designed software package

关键词： rice genome draft sequences.

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