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Precise orbit determination for BDS satellites

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Satellite Navigation 2022年第1期3卷 1-24,I0002页

作者： Qile Zhao Jing Guo Chen Wang Yifei Lyu Xiaolong Xu chao Yang Junqiang li GNSS Research Center Wuhan University129 Luoyu RoadWuhan 430079China School of Geological Engineering and Geomatics 126 Yanta RoadXi’an 710064China School of Geodesy and Geomatics Wuhan University129 Luoyu RoadWuhan 430079China.

Since the frst pair of BeiDou satellites was deployed in 2.00,China has made continuous eforts to establish its own independent BeiDou Navigation Satellite System(BDS)to provide the regional radio determination satellite service as well as regional and global radio navigation satellite services,which rely on the high quality of orbit and clock *** article summarizes the achievements in the precise orbit determination(POD)of BDS satellites in the past decade with the focus on observation and orbit dynamic ***,the disclosed metadata of BDS satellites is presented and the contribution to BDS POD is *** complete optical properties of the satellite bus as well as solar panels are derived based on the absorbed parameters as well the material ***,the status and tracking capabilities of the L-band data from accessible ground networks are presented,while some low earth orbiter satellites with onboard BDS tracking capability are *** topological structure and measurement scheme of BDS Inter-Satellite-link(ISL)data are *** highlighting the progress on observation models as well as orbit perturbations for BDS,e.g.,phase center corrections,satellite attitude,and solar radiation pressure,diferent POD strategies used for BDS are *** addition,the urgent requirement for error modeling of the ISL data is emphasized based on the analysis of the observation noises,and the incompatible characteristics of orbit and clock derived with L-band and ISL data are illuminated and *** further researches on the improvement of phase center calibration and orbit dynamic models,the refnement of ISL observation models,and the potential contribution of BDS to the estimation of geodetic parameters based on L-band or ISL data are *** this,it is promising that BDS can achieve better performance and provides vital contributions to the geodesy and navigation.

关键词： BDS Orbit and clock Solar radiation pressure Attitude Phase center correction Inter-satellite-link

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尼达尼布治疗进展性肺纤维化的疗效分析

锦州医科大学学报 2024年第4期45卷 88-92,96页

作者：闫丽丽李鑫焦雪刘超单丽娜锦州医科大学附属第一医院辽宁锦州121000

目的探讨进展性肺纤维化(progressive pulmonary fibrosing,PPF)患者应用尼达尼布治疗的临床效果及安全性分析。方法回顾性分析2.2.年6月至2.2.年10月在锦州医科大学附属第一医院住院确诊为PPF的患者的临床资料(80例),依据是否应用尼达... 详细信息

目的探讨进展性肺纤维化(progressive pulmonary fibrosing,PPF)患者应用尼达尼布治疗的临床效果及安全性分析。方法回顾性分析2.2.年6月至2.2.年10月在锦州医科大学附属第一医院住院确诊为PPF的患者的临床资料(80例),依据是否应用尼达尼布治疗分为常规治疗组37例和尼达尼布治疗组43例,均通过完善检查明确病因,并给予病因治疗及对症治疗,尼达尼布治疗组在此基础上给予联合尼达尼布治疗。比较两组患者治疗前和治疗6个月后的肺功能DLCO%、FVC%指标、PaO_(2.、六分钟步行试验(6 minute walking test,6MWT)距离、胸部HRCT评分和不良反应发生率。结果尼达尼布治疗组患者FVC%、DLCO%、PaO_(2.以及6MWT距离优于常规治疗组(P0.05)。结论尼达尼布治疗能够延缓PPF患者肺功能的下降速度。延缓肺纤维化进展,提高生活质量且治疗期间未增加不良反应发生率。

关键词：进展性肺纤维化尼达尼布肺功能六分钟步行试验

基于多源数据融合的城市出租车载客出行特征研究——以岳阳市为例

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交通运输系统工程与信息 2018年第2期18卷 45-51页

作者：唐艳丽蒋超郑伯红李茜铭中南大学土木工程学院长沙410075 岳阳市规划局湖南岳阳414000 中南大学建筑与艺术学院长沙410075

为探究城市出租车载客出行特征,在出租车GPS轨迹大数据基础上,融合居民出行调查数据、城市土地利用数据及天气数据,构建出租车载客出行量回归模型,得出出租车载客出行量与片区岗位数、天气状况、时段、片区面积有较强的相关性,而基于RB... 详细信息

为探究城市出租车载客出行特征,在出租车GPS轨迹大数据基础上,融合居民出行调查数据、城市土地利用数据及天气数据,构建出租车载客出行量回归模型,得出出租车载客出行量与片区岗位数、天气状况、时段、片区面积有较强的相关性,而基于RBF神经网络构建的回归模型在上述4个因素的基础上增加了片区常住人口数和是否工作日2.因素.通过10折交叉验证表明,RBF神经网络回归模型的拟合效果比多元线性回归模型更好.

关键词：城市交通 GPS大数据时空分布多元线性回归 RBF神经网络 10折交叉验证

Surface-modification effect of MgO nanoparticles on the electrical properties of polypropylene nanocomposite

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High Voltage 2020年第3期5卷 249-255页

作者： Shixun Hu Yao Zhou chao Yuan Wei Wang Jun Hu Qi li Jinliang He Beijing Key Lab of High Voltage&EMC and State Key Lab of Alternate Electrical Power System with Renewable Energy SourcesNorth China Electric Power UniversityBeijing 102206People's Republic of China Department of Electrical Engineering State Key Laboratory of Power SystemsTsinghua UniversityBeijing 100084People's Republic of China

Polypropylene(PP)-based nanocomposite is a promising insulation material for recyclable high-voltage direct current(HVDC)cables,where the coupling agent plays an important *** this study,four silane coupling agents with different alkyl chain groups(methyl,propyl,octyl,and octadecyl)were used to surface-modify magnesium oxide(MgO)*** surface-modification effect on the electrical properties of PP/MgO nanocomposites was *** results show that surface-modified nanoparticles introduce quantities of deep traps,whose quantity increases as the alkyl chain length *** similar tendency also occurs on DC volume *** these nanocomposites show remarkable space charge suppression ability and improved DC breakdown *** them,the nanocomposites with octyl-modified MgO show the best electrical properties,which could be attributed to the introduction of a large quantity of deep *** work may give a reference for the selection of coupling agents in PP-based nanocomposite insulation material for HVDC cable.

关键词： electrical coupling insulation

Photochemical and electrochemical strategies in C-F bond activation and functionalization

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Organic Chemistry Frontiers 2022年第3期9卷 853-873页

作者： Zhanghong Wang Yu Sun liu-Yu Shen Wen-chao Yang Fei Meng Pinhua li College of Eco-Environmental Engineering Guizhou Minzu UniversityGuiyang 550025PR China School of Horticulture and Plant Protection Yangzhou UniversityYangzhou 225009P.R.China Anhui Laboratory of Clean Catalytic Engineering Anhui Laboratory of Functional Complexes for Materials Chemistry and ApplicationCollege of Chemical and Environmental EngineeringAnhui Polytechnic UniversityWuhuAnhui 241000P.R.of China

The activation and functionalization of C-F bonds under mild conditions can serve as an important tool for organic syntheses including the modification of pharmaceuticals and agrochemicals and the synthesis of value-a... 详细信息

关键词： bonds activation functionalization

Energy transfer followed by electron transfer(ETET)endows a TPE-NBD dyad with enhanced environmental sensitivity

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Chinese Chemical Letters 2021年第6期32卷 1937-1941页

作者： Xia Wu Dongyang li Jin li Weijie Chi Xie Han chao Wang Zhaochao Xu Jun Yin Xiaogang liu Fluorescence Research Group Singapore University of Technology and DesignSingapore 487372Singapore Key Laboratory of Pesticide and Chemical Biology Ministry of EducationHubei International Scientific and Technological Cooperation Base of Pesticide and Green SynthesisInternational Joint Research Center for Intelligent Biosensing Technology and HealthCollege of ChemistryCentral China Normal UniversityWuhan 430079China CAS Key Laboratory of Separation Science for Analytical Chemistry Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Energy transfer and electron transfer are both fundamental mechanisms enabling numerous functional materials and *** most materials systems employ either energy transfer or electron transfer,the combined effect of energy and electron transfer processes in a single donor/acceptor system remains largely ***,we demonstrated the energy transfer followed by electron transfer(ETET)process in a molecular dyad *** to energy transfer,the fluorescence of TPE-NBD was greatly enhanced in non-polar *** contrast,polar solvents activated subsequent electron transfer and markedly quenched the emission of ***,ETET endows TPE-NBD with significant polarity *** expect that employing ETET could generate many functional materials with unprecedented properties,i.e.,for single laser powered multicolor fluorescence imaging and sensing.

关键词： Energy transfer Electron transfer Polarity probes Environmental sensitivity

REE concentrations of garnet and omphacite in eclogites from the Dabie Mountain, central China

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Chinese Journal Of Geochemistry 2013年第1期32卷 85-94页

作者： li Jing DU Jianguo CHANG Qing liU Lei CUI Yueju XIE chao SUN Yutao Institute of Earthquake Science China Earthquake Administration Institute of Disaster Prevention Institute for Research on Earth Evolution (IFREE) Japan Agency for Marine-Earth Science and Technology (JAMSTEC)

Distributions of the rare-earth elements (REE) in omphacite and garnet and REE behaviors during metamorphic processes were discussed. The REE concentrations of garnet and omphacite in six eclogite samples from the Dabie Mountain, central China, were measured by inductively coupled plasma-mass spectrometry (ICP-MS). The correlation of δEu ratios between garnet and omphacite indicated that chemical equilibrium of REE distribution between garnet and omphacite could be achieved during ultra-high pressure (UHP) metamorphism. Most of the partition coefficients (Kd=CiOmp/CiGrt) of light rare-earth elements (LREE) are higher than 1. However the partition coefficients of heavy rare-earth elements (HREE) are lower than 1. This indicated that the LREE inclined to occupy site M2.in omphacite, but the HREEs tended to occupy eightfold coordinated site in garnet during the eclogite formation. The REE geochemistry of the eclogites indicated that LREE could be partially lost during the prograde metamorphic process of protolith, but be introduced into the rocks during the symplectite formation. LREE are more active than HREE during the UHP metamorphism. The results are favorable to highlighting the REE behavior and evolution of UHP metamorphic rocks.

关键词：稀土元素分布石榴子石元素浓度绿辉石榴辉岩大别山中国电感耦合等离子体质谱

Rh-incompatible hemolytic disease of the newborn in Hefei

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World Journal of Clinical Cases 2019年第20期7卷 3202-3207页

作者： Shao-Hua Bi liang-liang Jiang li-Ying Dai Hong Zheng Jian Zhang li-li Wang chao Wang Qiao Jiang Yu liu Yong-li Zhang Juan Wang chao Zhu Guang-Hui liu Ru-Jeng Teng Divisions of Neonatology Anhui Provincial Children’s HospitalHefei 230022Anhui ProvinceChina Pediatrics Neurology Anhui Provincial Children’s HospitalHefei 230022Anhui ProvinceChina Division of Neonatology First Affiliated Hospital of Anhui Medical UniversityHefei 230022Anhui ProvinceChina Hefei Blood Center Hefei 230022Anhui ProvinceChina Clinical pathology Anhui Provincial Children’s HospitalHefei 230022Anhui ProvinceChina Division of Neonatology Department of PediatricsMedical College of WisconsinMilwaukeeWI 53226United States

BACKGROUND Anti-D antibody is not the common cause of Rh-isoimmunization in Chinese neonatal *** change in national population policy has followed by an increase in Rh-isoimmunization related hemolytic disease of the newborn(HDN).Unfortunately,regional status of Rh-HDN is *** hypothesize that Rh-HDN in our region is most commonly due to anti-E *** To investigate the prevalence of hemolytic disease of the newborn due to Rhisoimmunization in Hefei *** Retrospective review of data obtained from Children’s Hospital of Anhui and Hefei Blood Center between January 2.17 and June *** of minor blood group antibody was studied in the corresponding *** Totally 4138 newborns with HDN admitted during the study period and 116(2.8%)received blood exchange transfusion(BET).Eighteen newborns(0.43%)with proven Rh-incompatible HDN were *** were not the first-born *** mothers were RhD(+)(72.)and five were RhD(-).The distribution of Rh-related antibodies in mothers was ten anti-E(55%),five anti-D(2.%),and for one anti-C,anti-c,and anti-E/c(6%)***(72.2.)were qualified for BET,relative risk for BET was 2..9 as compared to other types of HDN,but only 10 received due to parenteral ***(100%)RhD related HDN received BET which is not significantly different from RhE related HDN(81.8%).CONCLUSION As expected,all Rh-incompatible HDN newborns were not the *** to the Caucasian population,anti-D induced HDN is not the most common *** our region,anti-E(11/18,61%)is the most common cause of Rh-HDN.

关键词： Rh-isoimmunization Hemolytic disease of the newborn Minor blood group

Isolation and Structural Indentification of Herbicidal Toxin Fractions Produced by Pythium aphanidermatum

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Agricultural Sciences in China 2010年第7期9卷 995-1000页

作者： ZHANG li-hui KANG Zhan-hai XU Jiao XU Wen-chao ZHANG Jin-lin College of Plant Protection Agricultural University of Hebei Baoding 071001 P.R. China

In order to understand the compsition and structure of herbicidal component of Pythium aphanidermatum,the isolation and structural indentification were *** culture filtrate was extracted by ethyl acetate,petroleum,and chloroform with the same volume respectively and the activity of the crude toxin was *** toxin was separated by using the method of thin layer chromatography（TLC）,then the main fraction was separated by HPLC,and the structure was analyzed by the sepctrum of IR,13C-NMR and *** results showed that the ethyl acetate extracts had the strongest herbicidal *** the method of TLC,the bioassay results showed that the extracts with Rf 0.19 had the strongest effect on weeds and the inhibition to Digitaria sanguinalis and Amaranthus retroflexus reached five levels,and the component was proved to be dimethyl o-phthalate from the spectrum of IR,13C-NMR and 1HNMR,which was one of the components from the toxin,and it had herbicidal activity.

关键词： Pythium aphanidermatum toxin herbicidal structure identification