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1Precise orbit determination of Beidou Satellites with precise positioning显示文摘Chinese Beidou satellite navigation system constellation currently consists of eight Beidou satellites and can provide preliminary service of navigation and positioning in the Asia-Pacific Region.Based on the self-developed software Position And Navigation Data Analysis(PANDA) and Beidou Experimental Tracking Stations (BETS),which are built by Wuhan University,the study of Beidou precise orbit determination,static precise point positioning (PPP),and high precision relative positioning,and differential positioning are carried out comprehensively.Results show that the radial precision of the Beidou satellite orbit determination is better than 10 centimeters.The RMS of static PPP can reach several centimeters to even millimeters for baseline relative positioning.The precision of kinematic pseudo-range differential positioning and RTK mode positioning are 2-4 m and 5-10 cm respectively,which are close to the level of GPS precise positioning.Research in this paper verifies that,with support of ground reference station network,Beidou satellite navigation system can provide precise positioning from several decimeters to meters in the wide area and several centimeters in the regional area.These promising results would be helpful for the implementation and applications of Beidou satellite navigation system.SHI Chuang ZHAO QiLe LI Min TANG WeiMing HU ZhiGang LOU YiDong ZHANG HongPing NIU XiaoJi LIU JingNan 2012Science China Earth Sciences2012,55,7:61
2Arrangement models of alkylammonium cations in the interlayer of HDTMA^+pillared montmorillonites显示文摘The orientation of HDTMA+ in the interlayer of organic pillared montmorillonites prepared at different concentrations of HDTMA+ have been studied using X-ray powder diffraction (XRD) and theoretical calculation. A series of arrangement models of HDTMA+ in the interlayer of montmorillonite have been proposed as lateral-monolayer (LM), lateral-bilayer (LB), pseudotrilayer (PT), paraf-fin-type-monolayer (PM), paraffin-type-bilayer (PB). With the increase of the concentration of HDTMA+, the arrange-ment model of HDTMA+ in the interlayer of montmorillo-nites changes as lateral-monolayer→lateral-bilayer→para- ffin-type monolayer→pseudotrilayer→paraffin-type-bilayer and the packing density of HDTMA+ in the interlayer in-creases gradually. In the intermediate stages, different mod-els may coexist.ZHU Jianxi, HE Hongping, GUO Jiugao, YANG Dan & XIE Xiande Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China Correspondence should be addressed to He Hongping 2003Chinese Science Bulletin2003,48,4:16
3Review on development of volumetric particle image velocimetry显示文摘Volumetric particle image velocimetry(PIV)is a laser technique measuring three-component velocity field in a volume.Common volumetric PIV techniques are defocusing PIV,multi-view PIV and holographic PIV.Tomographic PIV is an advanced approach of multi-view PIV,which significantly improves the spatial resolution of the measurement by using the multiplicative algebraic reconstruction technique(MART)to reconstruct the particle field.Due to the rapid progress being made in volumetric PIV measurements,this article focuses on introducing the principles of different volumetric PIV methods from aspects of particle reconstruction and velocity reconstruction.Advantages and limitations on applications are elaborated.Issues specific to volumetric PIV regarding illumination,digital imaging,depth of focus,ghost particle and spatial resolution are discussed.GAO Qi WANG HongPing SHEN GongXin 2013Chinese Science Bulletin2013,58,36:16
4Synthesis, characterization and size control of zerovalent iron nanoparticles anchored on montmorillonite显示文摘Zerovalent iron nanoparticles have been successfully synthesized using sodium borohydride solution reduction of ferric trichloride hexahydrate in the presence of montmorillonite as an effective protective reagent and support as well. A combination of characterizations reveals that with high monodispersity these obtained iron nanoparticles are well dispersed on clay surface, virginal from boron related impurity, and oxidation resistant well with iron core-iron oxide shell structure. The shell thickness of 3 nm remains almost invariable under ambient conditions. The size control of these iron nanoparticles has been achieved by tailoring the amount of the ferric iron, which mainly depends on the protective action of montmorillonite.FAN MingDe YUAN Peng CHEN TianHu HE HongPing YUAN AiHua CHEN KangMin ZHU JianXi LIU Dong 2010Chinese Science Bulletin2010,55,11:15
5Contrasting Effects of Ethylene Biosynthesis on Induced Plant Resistance against a Chewing and a Piercing-Sucking Herbivore in Rice显示文摘乙烯是有在草食动物抵抗上对比效果的压力荷尔蒙。然而,这些差别是否植物特定或草食动物特定,仍然保持未知。我们克隆米饭 1-aminocyclopropane-1-carboxylic 酸(ACC ) synthase 基因, OsACS2,其抄本响应由二个重要害虫的机械伤害和群袭是很快起来调整的:有斑纹的茎 borer (SSB ) Chilo suppressalis 和棕色的 planthopper (BPH ) Nilaparvata lugens。OsACS2 (当交流) 的 Antisense 表示减少了得到的乙烯排放,得到 SSB 的胰岛素朊酶禁止者(TrypPI ) 活动,导致 SSB 的不稳定的版本,和 SSB 抵抗。ACC 的外长的申请恢复了 TrypPI 活动和 SSB 抵抗。与 SSB 相对照, BPH 群袭在当交流线增加了不稳定的排放。因此, BPH 喜欢喂并且在上产卵野类型(WT ) 能被归因于二讨厌的 volatiles, 2-heptanone 和 2-heptanol 的 plantsan 效果,那被当交流植物在更高的数量射出。BPH 蜜露排泄被减少,生来的敌人吸引力在当交流线被提高,导致到 BPH 的更高全面的抵抗。这些结果证明发信号的乙烯对咀嚼和一只穿透吸昆虫在米饭防卫回答和电阻上有形成对照的、草食动物特定的效果,并且可以调停在不同的喂的草食动物之间的抵抗交易在米饭的行业协会。Jing Lu Jiancai Li Hongping Ju Xiaoli Liu Matthias Erb Xia Wang Yonggen Lou 2014Molecular Plant2014,7,11:15
6Distribution characteristics and ecological risk assessment of PAHs in surface waters of China显示文摘The concentrations of PAHs in the surface waters from seven river basins in China were summarized from literature published from 2000-2010. Subsequently, the risks from individual PAHs and ∑PAHs in the surface waters of China were quantified by comparing the overlap between the probability distributions of exposure concentrations with the probability distributions of toxicity data. The results show that the concentrations of 15 PAHs in the surface waters ranged from 3.09 to 38139.00 ng L-1, with a geometric mean of 474.93 ng L-1. The significantly higher concentrations of the 15 PAHs occurred in the surface waters from northern China when compared with those from southern China. The concentrations of the 15 PAHs in Chinese surface waters were higher than those in other waters worldwide. The MOS10 (margin of safety) values were calculated at 90th percentile values of exposure concentrations and 10th percentile values of toxicity data, with 5.75, 0.17, 2.33, 0.30, 0.57, 1.74, 1.05, and 0.11 for Ace, Ant, Flu, BaP, Flua, Nap, Phe, and Pyr, respectively. The probabilities of the individual PAH concentrations exceeding the 10th percentile value of the toxicity data were 6.06%, 2.07%, 9.51%, and 2.07% for Nap, Ace, Phe, and Flu, respectively, suggesting minimal risk to aquatic organisms; however, the probabilities of BaP, Ant, Flua, and Pyr exceeding this value were 19.49%, 25.46%, 15.15%, and 30.50%, respectively, indicating potential risks. Among the individual PAHs, the ecological risk from Pyr was the highest, followed by, in descending order of risk, Ant, Bap, Flua, Phe, Nap, Flu, and Ace. Additionally, the combined ecological risk of ∑PAH8 in Chinese surface waters was significantly higher than any that of individual PAHs alone. The MOS10 values in the river basins were < 1, except for the Haihe River Basin, suggesting a potential combined risk from ∑PAH8 in the other six river basins. The probabilities calculation indicate that low to high ecological risk from ∑PAH8 for all aquatic species was reported in the Liaohe River Basin (65.58%), Huaihe River Basin (57.15%), Songhua River Basin (46.49%), Pearl River Basin (38.41%), Yangtze River Basin (25.98%), Yellow River Basin (15.92%), and Haihe River Basin (5.22%).GUO GuangHui WU FengChang HE HongPing ZHANG RuiQing LI HuiXian FENG ChengLian 2012Science China Earth Sciences2012,55,6:14
7A modified Kelvin impact model for pounding simulation of base-isolated building with adjacent structures显示文摘基础隔离能有效地在一座上层建筑上减少地震力量,在特别地低 -- 到中等上升的大楼。在强壮的近差错的地面运动下面,然而跳可以发生在在孤立底的大楼(围嘴) 和它的包围挡土墙之间的隔离水平。为了有效地调查在估计通常使用的一些以后,与邻近的结构跳的 BIB 的行为,影响当模特儿,一个修改凯尔文影响模型在这篇论文被建议。在修改凯尔文模型的相关参数理论上通过一个简单的跳案例被导出并且数字地验证了。同时,孤立的上层建筑的无弹力被介绍以便精确地评估潜在的损坏到与邻近的结构跳 BIB 引起的上层建筑。修改凯尔文影响模型的可靠性与另外的影响模型一起通过数字比较被验证。然而,从各种各样的影响的数字结果之间的差别分析模型不是重要的。围嘴的许多数字模拟被进行调查各种各样的设计参数的影响并且在跳期间在山峰上调节内部故事的飘移和地板加速。跳能实质地增加地板加速,这被显示出,特别在影响发生的一楼。颤动的更高的模式在跳期间是激动的,增加而不是保留上层建筑的一个将近僵硬身体的运动的内部故事的飘移。而且,更高的韧性要求能在上层建筑的更低的地板上被强加。而且,影响僵硬似乎在隔离水平和上层建筑的更低的地板的内部故事的飘移在加速反应起一个重要作用。最后,数字结果证明隔离系统的过多的灵活性过去常最小化加速可以引起 BIB 更产生在有限地震差距下面跳的地板。Ye Kun Li Li Zhu Hongping 2009Earthquake Engineering and Engineering Vibration2009,8,3:13
8Rapid Detection of Filoviruses by Real-time TaqMan Polymerase Chain Reaction Assays显示文摘Ebola virus (EBOV) and Marburg virus (MARV) are causative agents of severe hemorrhagic fever with high mortality rates in humans and non-human primates and there is currently no licensed vaccine or therapeutics. To date, there is no specific laboratory diagnostic test in China, while there is a national need to provide differential diagnosis during outbreaks and for instituting acceptable quarantine procedures. In this study, the TaqMan RT-PCR assays targeting the nucleoprotein genes of the Zaire Ebolavirus (ZEBOV) and MARV were developed and their sensitivities and specificities were investigated. Our results indicated that the assays were able to make reliable diagnosis over a wide range of virus copies from 103 to 109, corresponding to the threshold of a standard RNA transcript. The results showed that there were about 1010 RNA copies per milliliter of virus culture supernatant, equivalent to 10,000 RNA molecules per infectious virion, suggesting the presence of many non-infectious particles. These data indicated that the TaqMan RT-PCR assays developed in this study will be suitable for future surveillance and specific diagnosis of ZEBOV and MARV in China.Yi Huang Hongping Wei Yunpeng Wang Zhengli Shi Herve Raoul Zhiming Yuan 2012Virologica Sinica2012,27,5:10
9A single camera volumetric particle image velocimetry and its application显示文摘Volumetric particle image velocimetry(VPIV) refers to a PIV-based technique which can obtain full velocity components in a three-dimensional measurement volume.A new VPIV method with a single lens was developed.A three-vision prism was used to make viewing from different angles using one camera.The technique was tested and successfully applied to a three-dimensional three-component(3D3C) measurement of a zero-net-mass-flux jet flow.The accuracy of the measurement was investigated,specifically in steps of calibration,self-calibration and particle triangulation.Time sequence of a vortex ring development was presented.It was shown that the measurement has high accuracy with validation rate of velocity vector reaching about 95%.The flow with vortex ring passing the measurement volume was studied using both swirl strength and vorticity magnitude criteria.Through comparison,the swirl criterion was found to be superior to the criterion of vorticity in differentiating the rotation motion and the free shear.GAO Qi WANG HongPing WANG JinJun 2012Science China(Technological Sciences)2012,55,9:10
10Metal Sealing Performance of Subsea X-tree Wellhead Connector Sealer显示文摘The metal sealing performance of subsea X-tree wellhead connectors is crucial for the safety and reliability of subsea X-trees. In order to establish the theoretical relation between metal sealing ring's contact stress and its structural parameters and working pressure, a mechanical analysis method for double-cone sealing of high pressure vessels is applied in analyzing the metal sealing ring under the condition of preload and operation. As a result, the formula of the unit sealing load for the metal sealing ring under operation with residual preload is shown in this paper, which ensures that the metal sealing ring has an excellent sealing effect and can prevent the metal sealing ring from yielding. Besides, while analyzing the sealing process of the metal sealing ring, the change rule of contact stress and working pressure is concluded here, putting forward that the structural parameters of the metal sealing ring are the major factors affecting the change rule. Finally, the analytical solution through theoretical analysis is compared with the simulation result through finite element analysis in a force feedback experiment, and both are consistent with each other, which fully verifies for the design and calculation theory on metal sealing ring's contact stress and its structural parameters and working pressure deduced in this paper. The proposed research will be treated as an applicable theory guiding the design of metal seal for subsea X-tree wellhead connectors.ZHAO Honglin CHEN Rui LUO Xiaolan DUAN Menglan LU Yinghui FU Guowei TIAN Hongping YE Daohui 2015Chinese Journal of Mechanical Engineering2015,28,3:9
11A Nowcasting Technique Based on Application of the Particle Filter Blending Algorithm显示文摘To improve the accuracy of nowcasting, a new extrapolation technique called particle filter blending was configured in this study and applied to experimental nowcasting. Radar echo extrapolation was performed by using the radar mosaic at an altitude of 2.5 km obtained from the radar images of 12 S-band radars in Guangdong Province,China. The first bilateral filter was applied in the quality control of the radar data; an optical flow method based on the Lucas–Kanade algorithm and the Harris corner detection algorithm were used to track radar echoes and retrieve the echo motion vectors; then, the motion vectors were blended with the particle filter blending algorithm to estimate the optimal motion vector of the true echo motions; finally, semi-Lagrangian extrapolation was used for radar echo extrapolation based on the obtained motion vector field. A comparative study of the extrapolated forecasts of four precipitation events in 2016 in Guangdong was conducted. The results indicate that the particle filter blending algorithm could realistically reproduce the spatial pattern, echo intensity, and echo location at 30-and 60-min forecast lead times. The forecasts agreed well with observations, and the results were of operational significance. Quantitative evaluation of the forecasts indicates that the particle filter blending algorithm performed better than the cross-correlation method and the optical flow method. Therefore, the particle filter blending method is proved to be superior to the traditional forecasting methods and it can be used to enhance the ability of nowcasting in operational weather forecasts.yuanzhao chen hongping lan xunlai chen wenhai zhang 2017Journal of Meteorological Research2017,31,5:9
12Purification and Characterization of a New Ribosome Inactivating Protein from Cinchonaglycoside C-treated Tobacco Leaves显示文摘A new ribosome-inactivating protein(RIP)with a molecular weight of 31 kDa induced by Cinchonaglycoside C(1)designatedCLP31,was isolated from tobacco leaves.Analysis of this protein sequence indicated that it belongs to the RIP family and itwas distinct from the other plant RIPs reported previously at its N-terminal amino acid sequence.CIP31 can directly impairsynthesis of coat protein(CP)of tobacco mosaic virus(TMV),which resulted in inhibition of TMV long distance movementand multiplication in tobacco plants at concentrations of ng/mL.Furthermore,no toxicity was shown to the growth andfertility of the plants.CIP31 was synthesized only in the presence of Cinchonaglycoside C(1)and was independent of thesalicylic acid(SA)signal pathway.We provided evidence for the SA-independent biological induction of resistance.Yanmei Li Yantao Jia Zhongkai Zhang Xiaoying Chen Hongping He Rongxiang Fang Xiaojiang Hao 2007Journal of Integrative Plant Biology2007,49,9:8
13Developing a bacteriophage cocktail for biocontrol of potato bacterial wilt显示文摘Bacterial wilt is a devastating disease of potato and can cause an 80% production loss. To control wilt using bacteriophage therapy, we isolated and characterized twelve lytic bacteriophages from different water sources in Kenya and China. Based on the lytic curves of the phages with the pathogen Ralstonia solanacearum, one optimal bacteriophage cocktail, P1, containing six phage isolations was formulated and used for studying wilt prevention and treatment efficiency in potato plants growing in pots. The preliminary tests showed that the phage cocktail was very effective in preventing potato bacterial wilt by injection of the phages into the plants or decontamination of sterilized soil spiked with R. solanacearum. Eighty percent of potato plants could be protected from the bacterial wilt(caused by R. solanacearum reference strain GIM1.74 and field isolates), and the P1 cocktail could kill 98% of live bacteria spiked in the sterilized soil at one week after spraying.However, the treatment efficiencies of P1 depended on the timing of application of the phages, the susceptibility of the plants to the bacterial wilt, as well as the virulence of the bacteria infected,suggesting that it is important to apply the phage therapy as soon as possible once there are early signs of the bacterial wilt. These results provide the basis for the development of bacteriophagebased biocontrol of potato bacterial wilt as an alternative to the use of antibiotics.Cuihua Wei Junli Liu Alice Nyarnbura Maina Francis B Mwaura Junping Yu Chenghui Yan Ruofang Zhang Hongping Wei 2017Virologica Sinica2017,32,6:8
14Bacteriophages, revitalized after 100 years in the shadow of antibiotics显示文摘The year 2015 marks 100 years since Dr.Frederick Twort discovered the'filterable lytic factor',which was later independently discovered and named 'bacteriophage' by Dr.Felix d’Herelle.On this memorable centennial,it is exciting to see a special issue published by Virologica Sinica on Phages and Therapy.In this issue,readers will not only fi nd that bacteriophage research isHongping Wei 2015Virologica Sinica2015,30,1:7
15Wharton's jelly mesenchymal stem cells differentiate into retinal progenitor cells显示文摘Human Wharton's jelly mesenchymal stem cells were isolated from fetal umbilical cord. Cells were cultured in serum-free neural stem cell-conditioned medium or neural stem cell-conditioned medium supplemented with Dkk-1, a Wnt/β catenin pathway antagonist, and LeftyA, a Nodal signaling pathway antagonist to induce differentiation into retinal progenitor cells. Inverted microscopy showed that after induction, the spindle-shaped or fibroblast-like Wharton's jelly mesenchymal stem cells changed into bulbous cells with numerous processes. Immunofluorescent cytochemical staining and reverse-transcription PCR showed positive expression of retinal progenitor cell markers, Pax6 and Rx, as well as weakly down-regulated nestin expression. These results demonstrate that Wharton's jelly mesenchymal stem cells are capable of differentiating into retinal progenitor cells in vitro.Ying Hu Jun Liang Hongping Cui Xinmei Wang Hua Rong Bin Shao Hao Cui 2013Neural Regeneration Research2013,8,19:7
16Mechanism of the interaction between Au nano-particles and polymerase in nanoparticle PCR显示文摘Nanoparticle PCR is a novel method to optimize DNA amplification. It performs well in improving specificity, enhancing sensitivity and speed. Several mechanisms were proposed in previous studies: one was based on the interaction between gold nanoparticles (AuNPs) and DNA while the other was attributed to the heat transfer property of AuNPs. In this paper, we propose that the interaction between AuNPs and DNA polymerase can significantly influence PCR. First, the addition of DNA polymerase can eliminate the inhibitory effects of excess AuNPs. Second, the addition of AuNPs will increase yield of the desired PCR product and make the optimum concentration of DNA polymerase move to higher value. Third, while excess polymerase might inhibit amplification efficiency, AuNPs can reverse this process and the yield of PCR amplification. Based on these results we propose a possible mechanism that AuNPs might modulate the activity of polymerase and improve PCR amplification.MI LiJuan ZHU HongPing ZHANG XiaoDong HU Jun FAN ChunHai 2007Chinese Science Bulletin2007,52,17:7
17Finite Element Model Updating of Bridge Structures Based on Sensitivity Analysis and Optimization Algorithm显示文摘The dynamic characteristics of bridge structures, such as the natural frequencies, mode shapes and model damping ratio, are the basis of structural dynamic computation, seismic analysis, vibration control and structural health condition monitoring. In this paper, a three-dimensional finite-element model is established for a highway bridge over a railway on No.312 National Highway and the ambient test is carried out in site, the dynamic characteristics of the bridge are studied using the finite-element analysis and ambient vibration measurements. Comparison between the theoretical and experimental results shows that the frequency differences of the modes range between 0.44% and 8.77%. If the measurement is more reliable, the finite element model updating is necessary. Thus, a set of de- sign variables is selected based on sensitivity analysis, then the finite ele- ment model of the bridge is updated based on optimization algorithm. The results of model updating show that the proposed updating method in this paper is more simple and effective, the updated finite element model can reflect the dynamic characteristics of the bridge better, the analytical results can provide the theoretical basis for damage identification and health con- dition monitoring of the bridge.HUANG Minshui ZHU Hongping 2008Wuhan University Journal of Natural Sciences2008,13,1:6
18Heterogeneous Fracture Simulation of Three-point Bending Plain-concrete Beam with Double Notches显示文摘Plain concrete is regarded as a two-phase material comprising randomly distributed aggregates and mortar matrix. A series of three-point bending concrete beams with symmetric or asymmetric double notches are modeled using the modified random aggregate generation and packing algorithm. The cohesive zone model is used as the fracture criterion and the cohesive elements are inserted into both the mortar matrix and the aggregate-mortar interfaces as potential micro-cracking zones. The dead and alive crack phenomena are studied experimentally and numerically; and the influences of notch location, aggregate distribution and gradation on fracture are numerically evaluated. Some important conclusions are given.Chuanchuan Zhang Xinhua Yang Hu Gao Hongping Zhu 2016Acta Mechanica Solida Sinica2016,29,3:6
19Preparation and characterization of 3-aminopropyl-triethoxysilane grafted montmorillonite and acid-activated montmorillonite显示文摘3-aminopropyltriethoxysilane grafted montmorillonites were synthesized with montmorillonite, acidactivated montmorillonites and 3-aminopropyltriethoxysilane in ethanol-water mixture. The resulting products were investigated using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TG). XRD patterns demonstrated that silane was intercalated into the montmorillonite gallery, indicated by increasing basal spacings. These intercalated silanes probably adopt bilayer arrangement models within the montmorillonite and acid-activated montmorillonites interlayer spaces. TG and DTG curves indicate that acidification results in a decrease of the thermal stability of the resultant montmorillonites. Silane grafting leads to a surface property transformation of montmorillonite from hydrophilicity to lipophilicity and an increase of the thermal stability of the condensed silanes.SHEN Wei HE HongPing ZHU JianXi YUAN Peng MA YueHong LIANG XiaoLiang 2009Chinese Science Bulletin2009,54,2:6
20An interpolating boundary element-free method (IBEFM) for elasticity problems显示文摘The paper begins by discussing the interpolating moving least-squares (IMLS) method. Then the formulae of the IMLS method obtained by Lancaster are revised. On the basis of the boundary element-free method (BEFM), combining the boundary integral equation method with the IMLS method improved in this paper, the interpolating boundary element-free method (IBEFM) for two-dimensional elasticity problems is presented, and the corresponding formulae of the IBEFM for two-dimensional elasticity problems are obtained. In the IMLS method in this paper, the shape function satisfies the property of Kronecker δ function, and then in the IBEFM the boundary conditions can be applied directly and easily. The IBEFM is a direct meshless boundary integral equation method in which the basic unknown quantity is the real solution to the nodal variables. Thus it gives a greater computational precision. Numerical examples are presented to demonstrate the method.REN HongPing 1 , CHENG YuMin 2 & ZHANG Wu 1 1 School of Computer Engineering and Science, Shanghai University, Shanghai 200072, China 2 Shanghai Institute of Applied Mathematics and Mechanics, Shanghai University, Shanghai 200072, China 2010Science China(Physics,Mechanics & Astronomy)2010,53,4:5
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