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| 1 | The principle of the positioning system based on communication satellites显示文摘It is a long dream to realize the communication and navigation functionality in a satellite system in the world. This paper introduces how to establish the system, a positioning system based on communication satellites called Chinese Area Positioning System (CAPS). Instead of the typical navigation satellites, the communication satellites are configured firstly to transfer navigation signals from ground stations, and can be used to obtain service of the positioning, velocity and time, and to achieve the function of navigation and positioning. Some key technique issues should be first solved; they include the accuracy position determination and orbit prediction of the communication satellites, the measur- ing and calculation of transfer time of the signals, the carrier frequency drift in communication satellite signal transfer, how to improve the geometrical configuration of the constellation in the system, and the integration of navigation & communication. Several innovative methods are developed to make the new system have full functions of navigation and communication. Based on the development of crucial techniques and methods, the CAPS demonstration system has been designed and developed. Four communication satellites in the geosynchronous orbit (GEO) located at 87.5°E, 110.5°E, 134°E, 142°E and barometric altimetry are used in the CAPS system. The GEO satellites located at 134°E and 142°E are decommissioned GEO (DGEO) satellites. C-band is used as the navigation band. Dual frequency at C1=4143.15 MHz and C2=3826.02 MHz as well as dual codes with standard code (CA code and precision code (P code)) are adopted. The ground segment consists of five ground stations; the master station is in Lintong, Xi’an. The ground stations take a lot of responsibilities, including monitor and management of the operation of all system components, determination of the satellite position and prediction of the satellite orbit, accomplishment of the virtual atomic clock measurement, transmission and receiving navigation signals to and from each satellite. In the north, the south, the east, the west and the center of Chinese main land, the function of CAPS demonstration system is checked and measured. In cars and on board the system is also checked and measured. The results are as follow: CA-code, horizontal positioning accuracy, 15-25 m (1σ), vertical, 1-3 m; P-code, horizontal positioning accuracy, 8-10 m (1σ), vertical, 1-3 m; velocity accuracy, CA-code, 0.13-0.30 m/s, P-code, 0.15-0.17 m/s; time accuracy, CA-code, 160 ns, P-code, 13 ns; determination accuracy of orbit ≤2 m. About 20 million US $ and two years are spent for the development of demonstration. A complete CAPS system is now being established. | AI GuoXiang SHI HuLi WU HaiTao LI ZhiGang GUO Ji | 2009 | Science China(Physics,Mechanics & Astronomy)2009，52，3： | 21 |
| 2 | Effect of Reclamation Time and Land Use on Soil Properties in Changjiang River Estuary,China显示文摘The objective of this study is to analyze soil physical and chemical properties,soil comprehensive functions and impact factors after different years of reclamation.Based on the survey data taken from 216 soil sampling points in the Fengxian Reclamation Area of the Changjiang (Yangtze) River Estuary,China in April 2009 and remotely sensed TM data in 2006,while by virtue of multivariate analysis of variance (MANOVA),geo-statistical analysis (GA),prin-cipal component analysis (PCA) and canonical correspondence analysis (CCA),it was concluded that:1) With the in-crease in reclamation time,soil moisture,soil salinity,soil electric conductivity and soil particle size tended to decline,yet soil organic matter tended to increase.Soil available phosphorous tended to increase in the early reclamation period,yet it tended to decline after about 49 years of reclamation.Soil nitrate nitrogen,soil ammonia nitrogen and pH changed slightly in different reclamation years.Soil physical and chemical properties reached a steady state after about 30 years of reclamation.2) According to the results of PCA analysis,the weighted value (0.97 in total) that represents soil nutrient factors (soil nitrate nitrogen,soil organic matter,soil available phosphorous,soil ammonia nitrogen,pH and soil particle size) were higher than the weighted value (0.48 in total) of soil limiting factors (soil salinity,soil elec-tric conductivity and soil moisture).The higher the F value is,the better the soil quality is.3) Different land use types play different roles in the soil function maturity process,with farmlands providing the best contribution.4) Soil physi-cal and chemical properties in the reclamation area were mainly influenced by reclamation time,and then by land use types.The correlation (0.1905) of the composite index of soil function (F) with reclamation time was greater than that with land use types (-0.1161). | SUN Yongguang LI Xiuzhen ülo MANDER HE Yanlong JIA Yue MA Zhigang GUO Wenyong XIN Zaijun | 2011 | Chinese Geographical Science2011，21，4： | 17 |
| 3 | Growth and nutrient dynamics of Betula alnoides seedlings under exponential fertilization显示文摘Betula alnoides is a fast-growing hardwood species grown in large plantations in Southeast Asia and South China.Nitrogen requirements for producing robus seedlings,growth and nutrient dynamics were investigated using exponential fertilization treatments.Root collar diameter,height,dry mass and nutrient contents of seedlings increased exponentially in all fertilization treatments as time progressed.Moreover,with water soluble fertilizer(Plant Products plus microelements N–P_2O_5–K_2O:20–20–20),300 mg N seedling^(-1)was adequate.Vector analysis revealed that P was the most responsive nutrient element followed by N and K.Dilutions of N and K were evident in the plants without N addition,which induced initial P sufficiency and then luxury consumption probably due to the antagonistic interaction between N and P.However deficiencies of N,P and K were mostly observed in al exponential regimes during the experiment because seedling growth rate exceeded nutrient uptake rate,inferring that further study on improving the nutrient uptake efficiency is needed.Analysis of relationships among nutrient supply,dry mass,N content and N concentration demonstrated that 100–400 mg N seedling^(-1)induced sufficiency to luxury consumption of nitrogen without significant change in dry mass,and 400 mg N seedling^(-1)is recommended to apply for nutrient loading of seedlings before outplanting.The findings will help improve seedling quality and enhance the production of robust seedlings for plantation forestry of this species. | Lin Chen Chunsheng Wang Bernard Dell Zhigang Zhao Junjie Guo Daping Xu Jie Zeng | 2018 | Journal of Forestry Research2018，29，1： | 14 |
| 4 | Sources and characteristics of fine particles over the Yellow Sea and Bohai Sea using online single particle aerosol mass spectrometer显示文摘Marine aerosols over the East China Seas are heavily polluted by continental sources. During the Chinese Comprehensive Ocean Experiment in November 2012, size and mass spectra of individual atmospheric particles in the size range from 0.2 to 2.0 μm were measured on board by a single particle aerosol mass spectrometer(SPAMS). The average hourly particle number(PN)was around 4560 ± 3240 in the South Yellow Sea(SYS), 2900 ± 3970 in the North Yellow Sea(NYS), and 1700 ± 2220 in the Bohai Sea(BS). PN in NYS and BS varied greatly over 3 orders of magnitude, while that in SYS varied slightly. The size distributions were fitted with two log-normal modes. Accumulation mode dominated in NYS and BS, especially during episodic periods. Coarse mode particles played an important role in SYS. Particles were classified using an adaptive resonance theory based neural network algorithm(ART-2a). Six particle types were identified with secondary-containing, aged sea-salt, soot-like, biomass burning, fresh sea-salt,and lead-containing particles accounting for 32%, 21%, 18%, 16%, 4%, and 3% of total PN,respectively. Aerosols in BS were relatively enriched in particles from anthropogenic sources compared to SYS, probably due to emissions from more developed upwind regions and indicating stronger influence of continental outflow on marine environment. Variation of source types depended mainly on origins of transported air masses. This study examined rapid changes in PN, size distribution and source types of fine particles in marine atmospheres. It also demonstrated the effectiveness of high-time-resolution source apportionment by ART-2a. | Huaiyu Fu Mei Zheng Caiqing Yan Xiaoying Li Huiwang Gao Xiaohong Yao Zhigang Guo Yuanhang Zhang | 2015 | Journal of Environmental Sciences2015，27，3： | 12 |
| 5 | Antibiotic growth promoter olaquindox increases pathogen susceptibility in fish by inducing gut microbiota dysbiosis显示文摘Low dose antibiotics have been used as growth promoters in livestock and fish. The use of antibiotics has been associated with reduced pathogen infections in livestock. In contrast, antibiotic growth promoter has been suspected of leading to disease outbreaks in aquaculture. However, this phenomenon is circumstantial and has not been confirmed in experimental conditions. In this study,we showed that antibiotic olaquindox increased the susceptibility of zebrafish to A. hydrophila infection. Olaquindox led to profound alterations in the intestinal microbiota of zebrafish, with a drastic bloom of Enterobacter and diminishing of Cetobacterium. Moreover, the innate immune responses of zebrafish were compromised by olaquindox(P<0.05). Transfer of microbiota to GF zebrafish indicated that while the immuo-suppression effect of olaquindox is a combined effect mediated by both OLA-altered micro biota and direct action of the antibiotic(P<0.05), the increased pathogen susceptibility was driven by the OLA-altered microbiota and was not dependent on direct antibiotic effect. Taken together, these data indicate that low level of OLA induced gut microbiota dysbiosis in zebrafish, which led to increased pathogen susceptibility. | suxu he quanmin wang shuning li chao ran xiaoze guo zhen zhang zhigang zhou | 2017 | Science China(Life Sciences)2017，60，11： | 10 |
| 6 | Transcriptional activation and phosphorylation of OsCNGC9 confer enhanced chilling tolerance in rice显示文摘Low temperature is a major environmental factor that limits plant growth and productivity.Although transient elevation of cytoplasmic calcium has long been recognized as a critical signal for plant cold tolerance,the calcium channels responsible for this process have remained largely elusive.Here we report that OsCNGC9,a cyclic nucleotide-gated channel,positively regulates chilling tolerance by mediating cytoplasmic calcium elevation in rice(Oryza sativa).We showed that the loss-of-function mutant of OsCNGC9 is defective in cold-induced calcium influx and more sensitive to prolonged cold treatment,whereas OsCNGC9 overexpression confers enhanced cold tolerance.Mechanistically,we demonstrated that in response to chilling stress,OsSAPK8,a homolog of Arabidopsis thaliana OST1,phosphorylates and activates OsCNGC9 to trigger Ca2+influx.Moreover,we found that the transcription of OsCNGC9 is activated by a rice dehydration-responsive element-binding transcription factor,OsDREB1A.Taken together,our results suggest that OsCNGC9 enhances chilling tolerance in rice through regulating cold-induced calcium influx and cytoplasmic calcium elevation. | Jiachang Wang Yulong Ren Xi Liu Sheng Luo Xiao Zhang Xin Liu Qibing Lin Shanshan Zhu Hua Wan Yang Yang Yu Zhang Bin Lei Chunlei Zhou Tian Pan Yongfei Wang Mingming Wu Ruonan jing Yang Xu Meng Han Fuqing Wu Cailin Lei Xiuping Guo Zhijun Cheng Xiaoming Zheng Yihua Wang Zhigang Zhao Ling Jiang Xin Zhang Yong-Fei Wang Haiyang Wang Jianmin Wan | 2021 | Molecular Plant2021，14，2： | 10 |
| 7 | Methods of rapid orbit forecasting after maneuvers for geostationary satellites显示文摘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 model.Based 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 force.The predicted orbit will soon be invalid after the maneuver starts,and it takes a long time to get a valid orbit after the maneuver ends.In order to improve ephemeris usability,the method of rapid orbit forecasting after maneuvers is studied.First,GEO satellite movement is analyzed in case of maneuvers based on the observation from the orbit meas-urement system by transfer.Then when a GEO satellite is in the free status just after maneuvers,the short arc observation is used to forecast the orbit.It is assumed that the common system bias and biases of each station are constant,which can be obtained from orbit determination with long arc observations.In 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 obtained.Actual 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. | YANG XuHai LI ZhiGang FENG ChuGang GUO Ji SHI HuLi AI GuoXiang WU FengLei QIAO RongChuan | 2009 | Science China(Physics,Mechanics & Astronomy)2009，52，3： | 10 |
| 8 | New inverter topology for ground current suppression in transformerless photovoltaic system application显示文摘An interesting inverter topology is proposed in this paper.It is similar to the typical three-phase full bridge inverter from the topology point of view,but smartly designed for the ground current reduction in single-phase photovoltaic(PV)inverter applications.Theoretical analysis is conducted to clarify the operation mechanism of the proposed topology.Performance evaluation is carried out to verify the effectiveness of the proposed topology for the ground current suppression. | Xiaoqiang GUO Huaibao WANG Zhigang LU Baocheng WANG | 2014 | Journal of Modern Power Systems and Clean Energy2014，2，2： | 9 |
| 9 | Compound-specific carbon isotope compositions of individual long-chain n-alkanes in severe Asian dust episodes in the North China coast in 2002显示文摘The molecular compositions and com- pound-specific carbon isotope compositions of indi- vidual long-chain n-alkanes of atmospheric aerosols collected during two severe Asian dust episodes in Qingdao in spring of 2002 were analyzed using gas chromatography/mass spectrometry (GC/MS) and gas chromatography/isotope ratio mass spectrometry (GC/IRMS). Typical plant wax n-alkanes (C29 and C31) had lower δ 13C values than those from anthropo- genic (engine exhaust) sources (C21―C23). The av- erage δ 13C value of plant wax n-alkane C29 in non-dust episode periods was -30.5‰ (?30.3‰― ?31.9‰), while -31.3‰ (?31.1‰―?31.5‰) in dust episode periods; for C31, it was ?31.4‰ (?31.1‰― ?33.0‰) in non-dust episode periods, and ?31.7‰ (?31.3‰―?32.6‰) in dust episode periods. Plant wax in the dust episode samples was mainly from herbaceous plants via long-range transport, while local plant wax was mainly from deciduous plants and woody plants. In North China coast, 83.3% of the plant wax in the severe dust episode samples was from C3 plants while 80.0% for the non-dust samples, indicating that plant wax transported to the north- western Pacific Ocean by airborne dust from East Asia was mainly from C3 plants. The results suggestthat the molecular and molecular-isotopic composi- tions of individual long-chain n-alkanes can, as an effective indicator, identify the terrestrial organic components in the dust from East Asia and sedi- ments in the northwest Pacific Ocean. | GUO Zhigang LI Juyuan FENG Jialiang FANG Ming YANG Zuosheng | 2006 | Chinese Science Bulletin2006，51，17： | 8 |
| 10 | A Brief Introduction to BNU-HESM1.0 and Its Earth Surface Temperature Simulations显示文摘Integrated assessment models and coupled earth system models both have their limitations in understanding the interactions between human activity and the physical earth system. In this paper,a new human–earth system model,BNUHESM1.0,constructed by combining the economic and climate damage components of the Dynamic Integrated Model of Climate Change and Economy to the BNU-ESM model,is introduced. The ability of BNU-HESM1.0 in simulating the global CO2 concentration and surface temperature is also evaluated. We find that,compared to observation,BNU-HESM1.0underestimates the global CO2 concentration and its rising trend during 1965–2005,due to the uncertainty in the economic components. However,the surface temperature simulated by BNU-HESM1.0 is much closer to observation,resulting from the overestimates of surface temperature by the original BNU-ESM model. The uncertainty of BNU-ESM falls within the range of present earth system uncertainty,so it is the economic and climate damage component of BNU-HESM1.0 that needs to be improved through further study. However,the main purpose of this paper is to introduce a new approach to investigate the complex relationship between human activity and the earth system. It is hoped that it will inspire further ideas that prove valuable in guiding human activities appropriate for a sustainable future climate. | YANG Shili DONG Wenjie CHOU Jieming FENG Jinming YAN Xiaodong WEI Zhigang YUAN Wenping GUO Yan TANG Yanli HU Jiacong | 2015 | Advances in Atmospheric Sciences2015，32，12： | 8 |
| 11 | Seasonal variation of sedimentation in the Changjiang Estuary mud area显示文摘Seasonal distributions of suspended matter and their sedimentary effect on the Changjiang Estuary mud area of the East China Sea were discussed, based on three cruise data of total suspended matter, temperature and salinity collected from the Changjiang Estuary and its adjacent area in summer and winter. The results show that the basic pattern of distributions of suspended matter in the study area is almost the same in winter and in summer. Sediments from Changjiang (Yangtze River) to the sea are chiefly trapped to the west of 123 o 15’E due to a strong obstruction of the Taiwan Warm Current. This suggests that these sediments are mainly transported and deposited in the inner shelf. The sediment supply, Taiwan Warm Current, and Zhejiang Coastal Current show a strong seasonal variation, which results in a strong seasonal variation of the sedimentary effect on this mud area. This mud area is a 'sink' of the Changjiang’s sediment discharge to the sea and its sedimentation is stronger in summer and weaker in winter. | GUO Zhigang,YANG Zuosheng,FAN Dejiang,PAN Yanjun(College of Marine Geosciences, Ocean University of China, Qingdao 266003, China) | 2003 | Journal of Geographical Sciences2003，13，3： | 8 |
| 12 | Global warming projections using the human–earth system model BNU-HESM1.0显示文摘Future climate change is usually projected by coupled earth system models under specific emission scenarios designed by integrated assessment models(IAMs),and this offline approach means there is no interaction between the coupled earth system models and the IAMs.This paper introduces a new method to design possible future emission scenarios and corresponding climate change, in which a simple economic and climate damage component is added to the coupled earth system model of Beijing Normal University(BNU-ESM). With the growth of population and technological expertise and the declining emission-to-output ratio described in the Dynamic Integrated Climate-Economy model, the projected carbon emission is 13.7 Gt C, resulting in a 2.4 °C warming by the end of the twenty-first century(2080–2099) compared with1980–1999. This paper also suggests the importance of the land and ocean carbon cycle in determining the CO2 concentration in the atmosphere. It is hoped that in the near future the next generation of coupled earth system models that include both the natural system and the social dimension will be developed. | Shili Yang Wenjie Dong Jieming Chou Jinming Feng Zhigang Wei Yan Guo Xiaohang Wen Ting Wei Di Tian Xian Zhu Zhiyong Yang | 2016 | Science Bulletin2016，61，23： | 7 |
| 13 | High salt diet accelerates the progression of murine lupus through dendritic cells via the p38 MAPK and STAT1 signaling pathways显示文摘The increased incidence of systemic lupus erythematosus(SLE)in recent decades might be related to changes in modern dietary habits.Since sodium chloride(NaCl)promotes pathogenic T cell responses,we hypothesize that excessive salt intake contributes to the increased incidence of autoimmune diseases,including SLE.Given the importance of dendritic cells(DCs)in the pathogenesis of SLE,we explored the influence of an excessive sodium chloride diet on DCs in a murine SLE model.We used an induced lupus model in which bone marrow-derived dendritic cells(BMDCs)were incubated with activated lymphocyte-derived DNA(ALD-DNA)and transferred into C57BL/6 recipient mice.We observed that a high-salt diet(HSD)markedly exacerbated lupus progression,which was accompanied by increased DC activation.NaCl treatment also stimulated the maturation,activation and antigenpresenting ability of DCs in vitro.Pretreatment of BMDCs with NaCl also exacerbated BMDC-ALD-DNA-induced lupus.These mice had increased production of autoantibodies and proinflammatory cytokines,more pronounced splenomegaly and lymphadenopathy,and enhanced pathological renal lesions.The p38 MAPK–STAT1 pathway played an important role in NaClinduced DC immune activities.Taken together,our results demonstrate that HSD intake promotes immune activation of DCs through the p38 MAPK–STAT1 signaling pathway and exacerbates the features of SLE.Thus,changes in diet may provide a novel strategy for the prevention or amelioration of lupus or other autoimmune diseases. | Ze Xiu Xiao Xiaojiang Hu Ximei Zhang Zhigang Chen Julie Wang Ke Jin Feng Lin Cao Baoqing Sun Joseph A.Bellanti Nancy Olsen Song Guo Zheng | 2020 | Signal Transduction and Targeted Therapy2020，5，1： | 6 |
| 14 | Senegenin promotes in vitro proliferation of human neural progenitor cells显示文摘Senegenin,an effective component of Polygala tenuifolia root extract,promotes proliferation and differentiation of neural progenitor cells in the hippocampus.However,the effects of senegenin on mesencephalon-derived neural progenitor cells remain poorly understood.Cells from a ventral mesencephalon neural progenitor cell line(ReNcell VM) were utilized as models for pharmaceutical screening.The effects of various senegenin concentrations on cell proliferation were analyzed,demonstrating that high senegenin concentrations(5,10,50,and 100 μmo/L),particularly 50 μmol/L,significantly promoted proliferation of ReNcell VM cells.In the mitogen-activated protein kinase signal transduction pathway,senegenin significantly increased phosphorylation levels of extracellular signal-regulated kinases.Moreover,cell proliferation was suppressed by extracellular signal-regulated kinase inhibitors.Results suggested that senegenin contributed to in vitro proliferation of human neural progenitor cells by upregulating phosphorylation of extracellular signal-regulated kinase. | Shi, Fang Liang, Zhigang Guo, Zixuan Li, Ran Yu, Fen Zhang, Zhanjun Wang, Xuan Wang, Xiaomin | 2011 | Neural Regeneration Research2011，6，3： | 5 |
| 15 | Universal thermodynamic model of calculating the mass action concentrations of omponents in a ternary strong electrolyte aqueous solution and its application in the NaCl-KCl-H_2O system显示文摘A universal thermodynamic model of calculating the mass action concentrations of components in a ternary strong elec-trolyte aqueous solution has been developed based on the ion and molecule coexistence theory,and verified in the NaCl-KCl-H2O ternary system at 298.15 K. To compare the difference of the thermodynamic model in binary and ternary strong electrolyte aqueous solutions,the mass action concentrations of components in the NaCl-H2O binary strong electrolyte aqueous solution were also com-puted at 298.15K. A transformation coefficient was required to compare the calculated mass action concentration and reported activ-ity because they were obtained at different standard states and concentration units. The results show that the transformation coeffi-cients between calculated mass action concentrations and reported activities of the same components change in a very narrow range. The calculated mass action concentrations of components in the NaCl-H2O and NaCl-KCl-H2O systems are in good agreement with the reported activities. This indicates that the developed thermodynamic model can reflect the structural characteristics of solutions,and the mass action concentration also strictly follows the mass action law. | Weijie Zhao Hanjie Guo Xuemin Yang Zhigang Dan | 2008 | Journal of University of Science and Technology Beijing2008，15，5： | 5 |
| 16 | Vertical structure and seasonal variation of tidal and residual currents in the northern Huanghai Sea显示文摘Analysis of tidal current and sea level has been made based on the observations from the summer of 2006 to the winter of 2007,respectively.The result indicates that a two-layer structure of residual current exists in summer,with its upper layer going northwestward and the lower layer southeastward.In addition,some strong residuals exist in the neighboring depth of the pycnocline during the current period of astronomical tide.In winter,except some individual layersthe residual currents mostly direct to the northwest,from which we can see the fluctuation of abnormal sea-level and the appearance of associated current because of the changes of the wind field.The analysis of tidal ellipse indicates that the direction of the maximum semidiurnal component is clockwise from summer to winter,with an angle of 16-18.Moreover,in summer the semidiurnal component rotates with depth clockwise while the diurnal component counterclockwise.However,the vertical structure is almost homogeneous in winter. | SONG Jun GUO Junru QIAO Lulu MU Lin YAO Zhigang LIU Yang LI Huan BAO Xianwen SUN Xiaoyan GAO Jia | 2011 | Acta Oceanologica Sinica2011，30，5： | 4 |
| 17 | Stability control of a deep shaft insert显示文摘The deterioration of a deep shaft insert at the Xing'an Coal Mine was analyzed by studying the physical and mechanical properties of the rock located at key positions relative to the shaft. Factors that influence shaft stability were obtained. The numerical simulation program FLAC3D was used to simulate the destruction of the deep shaft insert. Two different support methods were analyzed by simulation. The simulations demonstrate that a single stiffness support is inappropriate for this shaft insert. The appropriate support method is an integrated coupling method of rigid and flexible supports. The flexible support is applied first and then the rigid support is second. Engineering practice in the Xing'an Coal Mine shows that this technology can effectively control deep-shaft insert deterioration. This support approach provides an important direction for future project design and construction, as well. | LI Guofeng | 2010 | Mining Science and Technology2010，20，4： | 4 |
| 18 | Effect of electrode Pt-loading and cathode flow-field plate type on the degradation of PEMFC显示文摘The electrode Pt-loading has an effect on the number of active sites and the thickness of catalyst layer,which has huge influence on the mass transfer and water management during dynamic process in PEMFCs. In this study, membrane electrode assemblies with different Pt-loadings were prepared, and PEMFCs were assembled using those membrane electrode assemblies with traditional solid plate and water transport plate as cathode flow-field plates, respectively. The performance and electrochemical surface area of cells were characterized to evaluate the membrane electrode assemblies degradation after rapid currentvariation cycles. Scanning electron microscope and transmission electron microscope were used to investigate the decay of catalyst layers and Pt/C catalyst. With the increase of Pt-loading, the performance degradation of membrane electrode assemblies will be mitigated. But higher Pt-loading means thicker catalyst layer, which leads to a longer pathway of mass transfer, and it may result in carbon material corrosion in membrane electrode assemblies. The decay of Pt/C catalyst in cathode is mainly caused by the corrosion of carbon support, and the degradation of anode Pt/C catalyst is a consequence of migration and aggregation of Pt particles. And using water transport plate is beneficial to alleviating the age of cathode Pt/C catalyst. | Lijuan Qu Zhiqiang Wang Xiaoqian Guo Wei Song Feng Xie Liang He Zhigang Shao Baolian Yi | 2019 | Journal of Energy Chemistry2019，28，8： | 4 |
| 19 | Wear properties of NiAl based materials | Jianting Guo Zhensheng Wang Liyuan Sheng Lanzhang Zhou Chao Yuan Zhigang Chen Li Song | 2012 | Progress in Natural Science:Materials International2012，22，5： | 3 |
| 20 | Bt protein expression in the transgenic insect-resistant cotton in China显示文摘According to statistics of International Service for the Acquisition of Agri-biotech Applications(ISAAA),18million farmers in 28 countries planted more than 181million hectares of genetically modified(GM)crops in2014,at an annual growth rate of between 3%–4%,with6.3 million ha more than 2013[1].Among these counties,China ranks the sixth with 3.9 million ha.Globally,27kinds of transgenic crops have been approved.The four main food groups for which GM varieties are | Guoqing Sun Dongling Zhang Rui Zhang Yuan Wang Zhigang Meng Tao Zhou Chenzhen Liang Tao Zhu Sandui Guo | 2016 | Science Bulletin2016，61，20： | 3 |
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