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Satellite Navigation 2023年第3期4卷 92-106页

作者： Ping Zeng Zhetao Zhang Yuanlan Wen Xiufeng He Lina He Muzi Li Wu Chen School of earth Sciences and Engineering Hohai UniversityNanjing 211100China Shanghai Aerospace Control Technology institute Shanghai 201109China Department of Land Surveying and Geo‑Informatics The Hong Kong Polytechnic UniversityHong KongChina

The Wide-Lane(WL)and Narrow-Lane(NL)Uncalibrated Phase Delays(UPDs)are the prerequisites in the traditional Precise Point Positioning(PPP)Ambiguity Resolution(AR).As the generation mechanism of various biases becomes more complex,we systematically studied the impact factors of four satellite systems WL and NL UPDs from the perspective of parameter *** 100 stations in a global network are used to generate the *** results of different satellite systems show that the estimation method,update frequency,and solution mode need to be treated *** regional networks with different receiver types,JAVAD,and Trimble,are also *** results indicate that the receiver-dependent bias has an influence on UPD ***,the hardware delays can inhibit the satellite-side UPDs if these receiver-specific errors are not fully deployed or even ***,the temporal stability and residual distribution of NL UPDs are significantly enhanced by utilizing a regional network,with the improvements by over 68%and 40%,*** demonstrates that different network scales exhibit the different implication of unmodeled errors,and the unmodeled errors cannot be ignored and must be handled in UPD estimation.

关键词： WL UPD NL UPD Satellite system Receiver type Network scale

Sedimentary characteristics and processes of the Paleogene Dainan Formation in the Gaoyou Depression, North Jiangsu Basin, eastern China

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Petroleum Science 2016年第3期13卷 385-401页

作者： Xia Zhang Chun-Ming Lin Yong Yin Ni Zhang Jian Zhou Yu-Rui Liu State Key Laboratory for Mineral Deposits Research School of Earth Sciences and EngineeringNanjing University School of Geographic and Oceanographic Sciences Nanjing University institute of Geological Sciences Jiangsu Oilfield Branch CompanySINOPEC

In this paper,the type,vertical evolution,and distribution pattern of sedimentary facies of the Paleogene Dainan Formation in the Gaoyou Depression of the North Jiangsu Basin are studied in *** show that fan delta,delta,nearshore subaqueous fan,and lacustrine facies developed during the Dainan Formation period and their distribution pattern was mainly controlled by tectonics and *** fan delta and nearshore subaqueous fan facies predominantly occur in the southern steep slope region where fault-induced subsidence is thought to have created substantial accommodation,whereas the delta facies are distributed on the northern gentle slope which is thought to have experienced less ***,the lacustrine facies is shown to have developed in the center of the depression,as well as on the flanks of the fan delta,delta,and nearshore subaqueous fan ***,the Dainan Formation represents an integrated transgressiveregressive cycle,with the E2d1being the transgressive sequence and the E2d2being the regressive *** distribution model of sedimentary facies plays an important role in predicting favorable reservoir belts for the Dainan Formation in the Gaoyou Depression and similar *** the Gaoyou Depression,sandstones of the subaqueous distributary channels in the fan delta and the subaqueous branch channels in the delta are characterized by physical properties favorable for reservoir formation.

关键词： Sedimentary facies Distribution pattern Sedimentary evolution Dainan Formation Gaoyou Depression North Jiangsu Basin

Progressive current degradation and breakdown behavior in GaN LEDs under high reverse bias stress

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Chinese Physics B 2017年第8期26卷 429-432页

作者：赵琳娜于沛洪郭子骧闫大为周浩吴锦波崔志强孙华锐顾晓峰 Engineering Research Center of Io T Technology Applications (Ministry of Education) Department of Electronic EngineeringJiangnan University School of earth and Space Sciences University of Science and Technology of China School of Science Harbin Institute of Technology (Shenzhen)

The progressive current degradation and breakdown behaviors of GaN-based light emitting diodes under high reversebias stress are studied by combining the electrical, optical, and surface morphology characterizations. The current features a typical “soft breakdown” behavior, which is linearly correlated to an increase of the accumulative number of electroluminescence spots. The time-to-failure for each failure site approximately obeys a Weibull distribution with slopes of about 0.67 and 4.09 at the infant and wear-out periods, respectively. After breakdown, visible craters can be observed at the device surface as a result of transient electrostatic discharge. By performing focused ion beam cuts coupled with scan electron microscope, we observed a local current shunt path in the surface layer, caused by the rapid microstructure deterioration due to significant current heating effect, consistent well with the optical beam induced resistance change observations.

关键词： GaN LEDs current degradation breakdown behavior reverse bias stress

Improvement of ecological geographic regionalization based on remote sensing and canonical correspondence analysis： A case study in China

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Science China earth Sciences 2016年第9期59卷 1745-1753页

作者： JIN JiaXin WANG Ying JIANG Hong KONG Yan LU XueHe ZHANG XiuYing Jiangsu Provincial Key Laboratory of Geographic Information Science and Technology Nanjing University Nanjing 210023 China International institute for earth System Science Nanjing University Nanjing 210023 China Information Center of Urban Planning Wuxi 214072 China

Ecological geographic regions, also called eco-regions, can be used to divide a remotely sensed image, which is helpful for reducing the complexity of land cover types within eco-regions and for improving the classification accuracy of land cover. In this case study in China, we improved a method of ecological geographic regionalization that is more suitable for remote sensing mapping of regional land cover, and we obtained new eco-regions. The canonical correspondence analysis(CCA) and k-means clustering were adopted in the ecological geographic regionalization using both seasonal remotely-sensed vegetation information and environmental data including climate, elevation and soil features. Our results show that the combination of seasonal vegetation information and the CCA performed well in the selection of the dominant environmental factor of the biogeographic pattern, and it can be used as regionalization indicators of eco-regions. We found that thermal factors are the most important driving forces of the biogeographic pattern in China, which followed by moisture factors. Two global land cover products(MODIS MCD12C1 and Glob Cover) were used to assess our eco-regions. The results show that our eco-regions performed better than that of a previous study regarding the complexity of land cover types, such as in the number of types and the proportional area of the major/secondary type. These results indicate that the method of ecological geographic regionalization, which is based on environmental factors associated with seasonal vegetation features, is effective for reducing the regional complexity of land cover.

关键词： Ecological geographic regionalization Remote sensing Canonical correspondence analysis k-means clustering Land cover

Acoustic-electrical properties and rock physics models for shale-oil formations:prediction of reservoir properties of interbedded sandstone and shale layers

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Applied Geophysics 2022年第4期19卷 485-502,603页

作者： Pang Meng-Qiang Ba Jing Wu Chun-Fang Carcione José Maria Müller Tobias School of earth Science and Engineering Hohai UniversityNanjingu211000China Bochum university of Applied Sciences D-44801 BochumGermany Shanghai Technical institute of Electronics and Information Shanghai201411China National institute of Oceanography and Applied Geophysics(OGS) SgonicoTrieste 34010

In recent years,the Yanchang shale-oil formations of the Ordos Basin are rich in reserves with complex lithology and structure characteristics,low porosity and low permeability,and weak anomalies for oil and water discriminations,have been the key targets of unconventional oil/gas resource exploration and development in the relevant *** joint acoustic-electrical(AE)properties can be used to interpret reservoir lithology,mineralogy,pore structure,and fluid *** conduct tests of thin section analysis,X-ray diff raction,and ultrasonic and electrical experiments at diff erent pressures and saturation degrees,cores from the shale-oil formations in the Q area of the basin are *** variations in AE properties with respect to clay content,porosity,pressure(microfracture),and saturation are *** experimental results indicate that the rock physics behaviors of sandstones with diff erent clay contents vary *** AE properties of clean sandstones are basically dependent on the microfractures(pressure),while for muddy sandstones,the clay content is an important factor affecting the *** target reservoir consists of interbedded sandstone and shale *** AE equivalent medium equations and the Gurevich theory are applied to establish the joint models for the diff erent lithologies and simulate the variations in AE properties with respect to fluid type,pore structure,and mineral *** three-dimensional joint templates of clean and muddy sandstones,as well as shale,are developed based on the elastic and electrical attributes and then calibrated using the experimental and well-log *** reservoir properties are estimated with the templates and validated by the log *** results indicate that the joint templates based on lithology characteristics can eff ectively characterize the properties of interbedded sandstone and shale ***,the combined application of AE data provides more beneficial informatio

关键词： shale-oil formations acoustic-electrical(AE)properties interbedded layers clay content pore structure rock physics model

Use of Total Precipitable Water Classification of A Priori Error and Quality Control in Atmospheric Temperature and Water Vapor Sounding Retrieval

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Advances in Atmospheric Sciences 2012年第2期29卷 263-273页

作者： Eun-Han KWON Elisabeth WEISZ School of earth and Environmental Sciences Seoul National University Seoul 151-747 Korea Cooperative institute for Meteorological Satellite Studies University of Wisconsin-Madison1225 West Dayton Street Madison WI 53706 USA

This study investigates the use of dynamic a priori error information according to atmospheric moistness and the use of quality controls in temperature and water vapor profile retrievals from hyperspectral infrared （IR） sounders. Temperature and water vapor profiles are retrieved from Atmospheric InfraRed Sounder （AIRS） radiance measurements by applying a physical iterative method using regression retrieval as the first guess. Based on the dependency of first-guess errors on the degree of atmospheric moistness, the a priori first-guess errors classified by total precipitable water （TPW） are applied in the AIRS physical retrieval procedure. Compared to the retrieval results from a fixed a priori error, boundary layer moisture retrievals appear to be improved via TPW classification of a priori first-guess errors. Six quality control （QC） tests, which check non-converged or bad retrievals, large residuals, high terrain and desert areas, and large temperature and moisture deviations from the first guess regression retrieval, are also applied in the AIRS physical retrievals. Significantly large errors are found for the retrievals rejected by these six QCs, and the retrieval errors are substantially reduced via QC over land, which suggest the usefulness and high impact of the QCs, especially over land. In conclusion, the use of dynamic a priori error information according to atmospheric moistness, and the use of appropriate QCs dealing with the geographical information and the deviation from the first-guess as well as the conventional inverse performance are suggested to improve temperature and moisture retrievals and their applications.

关键词： atmospheric sounding AIRS total precipitable water a priori error quality control

Mechanism of micro-wetting of highly hydrophobic coal dust in underground mining and new wetting agent development

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International Journal of Mining Science and Technology 2023年第1期33卷 31-46页

作者： Mingzhong Gao Hongmei Li Yun Zhao Yiting Liu Weiqi Zhou Luming Li Jing Xie Jie Deng State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu 610065China Guangdong Provincial Key Laboratory of Deep earth Sciences Geothermal Energy Exploitation and UtilizationInstitute of Deep Earth Sciences and Green EnergyCollege of Civil and Transportation EngineeringShenzhen UniversityShenzhen 518060China College of Food and Bioengineering Chengdu UniversityChengdu 610106China School of Mechanical Engineering Chengdu UniversityChengdu 610106China

The internal mechanism of the high hydrophobicity of the coal samples from the Pingdingshan mining area was studied through industrial,element,and surface functional group *** testing and molecular dynamics simulations were employed to study the impact of three types of surfactants on the surface adsorption properties and wettability of highly hydrophobic bituminous *** results show that the surface of highly hydrophobic bituminous coal is compact,rich in inorganic minerals,and poorly wettable and that coal molecules are dominated by hydrophobic functional groups of aromatic rings and aliphatic *** wetting performance of surfactants as the intermediate carrier to connect coal and water molecules is largely determined by the interaction force between surfactants and coal(Fs-c)and the interaction force between surfactants and water(Fs-w),which effectively improve the wettability of modified coal dust via modifying its surface electrical properties and surface energy.A new type of wetting agent with a dust removal rate of 89%has been developed through discovery of a compound wetting agent solution with optimal wetting and settling *** paper provides theoretical and technical support for removing highly hydrophobic bituminous coal dust in underground mining.

关键词： Dust removal technology Bituminous coal dust New dust suppressant Mine safety Molecular dynamics

Light-stabilized FHA2 suppresses miRNA biogenesis through interactions with DCL1 and HYL1

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Molecular Plant 2021年第4期14卷 647-663页

作者： Seung Jun Park Suk Won Choi Gu Min Kim Christian Moller Hyun-Sook Pai Seong Wook Yang Department of Systems Biology College of Life Science and BiotechnologyYonsei UniversitySeoul 120749Korea EDepartment of Systems Biology Institute of Life Science and BiotechnologyYonsei UniversitySeoul 120-749Korea Department of Plant and Environnental Sciences Faculty of ScienceUniversity of CopenhagenThorvaldsensvei 40DK-1871 FrederiksbergCopenhagenDenmark Pohang university of Science and Technology(POSTECH) 77 Cheongam-RoNam-GuPohangGyeongbuk37673.Korea These authors contributed equally to this article.

The precise regulation of microRNA(miRNA)biogenesis is crucial for plant development,which requires core microprocessors and many fine tuners to coordinate their miRNA processing activity/specificity in fluctuating cellular *** de-etiolation,light triggers a dramatic accumulation of core microprocessors and primary miRNAs(pri-miRNAs)but decreases pri-miRNA processing activity,resulting in relatively constant miRNA *** mechanisms underlying these seemingly contradictory regulatory changes remain *** this study,we identified forkhead-associated domain 2(FHA2)as a light-stabilized suppressor of miRNA *** found that FHA2 deficiency increased the level of mature miRNAs,accompanied by a reduction in pri-miRNAs and target *** assays showed that FHA2 associates with the core microprocessors DCL1,HYL1,and SE,forming a complex to suppress their pri-miRNA processing *** analyses revealed that FHA2 promotes HYL1 binding but inhibits the binding of DCL1-PAZ-RNase-RNA-binding domains(DCL1-PRR)to miRNAs,whereas FHA2 does not directly bind to these ***,we found that FHA2 protein is unstable in the dark but stabilized by light during ***,disruption of FH A led to defects in light-triggered changes in miRNA expression and reduced the survival rate of deetiolated seedlings after prolonged light ***,these data suggest that FHA2 is a novel light-stabilized suppressor of miRNA biogenesis and plays a role in fine-tuning miRNA processing during de-etiolation.

关键词： miRNA biogenesis Suppressor of the microprocessor miRNA-biogenetic inconsistency

Efficient and stable perovskite solar cells by build-inπ-columns and ionic interfaces in covalent organic frameworks

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Nano Research 2023年第7期16卷 9387-9397页

作者： Riming Nie Xiaokai Chen Zhongping Li Weicun Chu Si Ma Changqing Li Xiaoming Liu Yonghua Chen Zhuhua Zhang Wanlin Guo State Key Laboratory of Mechanics and Control of Mechanical Structures Key Laboratory for Intelligent Nano Materials and Devices of the Ministry of EducationInstitute for Frontier ScienceNanjing University of Aeronautics and AstronauticsNanjing 210016China Department of Chemical and Biomolecular Engineering Yonsei University50 Yonsei-roSeodaemun-guSeoul 120-749Republic of Korea College of Chemistry Jilin UniversityChangchun 130012China Department of Energy and Chemical Engineering Ulsan National Institute of Science and Technology(UNIST)50 UNIST-gilEonyang-eupUljugunUlsan 44919Republic of Korea Key Laboratory of Flexible Electronics(KLoFE) School of Flexible Electronics(Future Technologies)&Institute of Advanced Materials(IAM)Nanjing Tech University(Nanjing Tech)Nanjing 211816China

Perovskite solar cells(PSCs)have attracted much attention due to their rapidly increased power conversion efficiencies,however,their inherent poor long-term stability hinders their *** degradation of PSCs first comes from the degradation of hole transport materials(HTMs).Here,we report the construction of periodicπ-columnar arrays and ionic interfaces over the skeletons by introducing cationic covalent organic frameworks(C-COFs)to the ***π-columnar arrays can optimize the charge transport ability and energy levels of the hole transport layer and suppress the degradation of HTM,and ionic interfaces over the skeletons can produce stronger electric dipole and electrostatic interactions,as well as higher charge *** C-COFs were designed and synthesized via Schiff base reaction by using 1,3,5-triformylphloroglucinol as a neutral knot and dimidium bromide as cationic *** neutral COFs(N-COFs)were also synthesized as a reference by using 3,8-diamino-6-phenylphenanthridine as neutral *** with cationic COF exhibit the highest efficiency of 23.4%with excellent humidity and thermal *** the best of our knowledge,this is the highest efficiency among the meso-structured PSCs fabricated by a sequential process.

关键词： cationic covalent organic framework(C-COF) π-columnar arrays ionic interfaces charge density perovskite solar cells

Pathways and mechanisms of lithium enrichment in brine deposits: Geochemical and isotopic evidence from the Bieletan section in the Qaidam Basin， northwestern China

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Journal of earth Science 2024年

作者： Yanjun Zhao Yufei Hu Lijian Shen Wanping Liu Ju Jiao Pengcheng Jiao Chenglin Liu M.Santosh MNR Key Laboratory of Metallogeny and Mineral Assessment， institute of Mineral Resources， Chinese Academy of Geological Sciences Qinghai Salt Lake Industry Co.， Ltd.， National Engineering Technology Research Center for Comprehensive Utilization of Salt Lake Resources，Qinghai Province Key Laboratory of Comprehensive Utilization of Salt Lake Resources China university of Geosciences(Wuhan) China university of Geosciences(Beijing) Department of earth Science， university of Adelaide yonsei Frontier Lab， yonsei university

Bieletan is one of the most important salt lake brine lithium deposits within the Qaidam Basin， northwestern China. In this study， we present the results of chemical composition and isotopic analyses of Li and Sr in brine samples collected from Bieletan hydrological observation wells in different seasons in 2020. We evaluated the evolution processes of Li+， K+， and other ions in the reservoir under the combined influence of sulfate-type river water， CaCl2-type brines， and artificial recharge. In long-term observation wells， the composition of shallow brines varies， and the compositions of deep brines and brines in brine production wells are relatively stable. The concentrations of Li+and B3+in the northern area are higher than those in the southern area， and the ion concentrations of the deep brines in the long-term observation wells are slightly higher than those of the shallow brines. The concentrations of K+and Mg2+vary to some extent in both the deep and shallow brines of the long-term observation wells but are less affected by the season. However， the Ca2+and Sr2+concentrations of the shallow brines show notable seasonal variations， indicating a significant effect of CaCl2-type brines. The decreases in the Li and Sr isotopes of brines in Senie Lake are caused by the inflow of Wutumeiren River water during the high-water period. This finding indicates that during the high-water period， surface brines of salt lakes replenish intercrystalline brines， whereas during the dry season， the intercrystalline brines replenish Senie Lake. This mixed mineralization process resulted in Li+enrichment in the study area， with the highest Li+concentration occurring in the northern area of the Bieletan section. Although the Li+concentration in shallow brines decreases due to exploitation， we predict that deep brines with higher concentrations of Li+would serve as important reserves for sustainable development.

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