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Global Freshwater Storage Capability across Time Scales in the GRACE Satellite Era

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Advances in Atmospheric Sciences 2021年第6期38卷 905-917页

作者： Enda ZHU xing yuan Key Laboratory of Regional Climate-Environment for Temperate East Asia(RCE-TEA) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China School of Hydrology and Water Resources Nanjing University of Information Science and TechnologyNanjing 210044China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

Freshwater is recharged mainly by rainfall and stored inland for a period of time,which is directly affected by its storage *** storage capability of river basins has different spatiotemporal features that are important for the predictability of freshwater ***,the estimation of freshwater storage capability(FSC)remains a challenge due to the lack of observations and quantification ***,we use a metric that characterizes hydrological“inertia”after rainfalls to analyze FSC over the 194 largest global major river basins based on satellite observations from the Gravity Recovery and Climate Experiment(GRACE)and simulations from the Community Land Model version 5(CLM5).During 2003–16,the global land was observed to retain 28%of precipitation after one month based on GRACE observations,and the simulation depicts that the retained proportions decrease from 42%after one day to 26%after one month,with smaller FSC partly attributed to wetter conditions and higher vegetation *** root zone contributes about 40%to the global land FSC on daily to monthly time *** the time scale increases,the contribution from the surface soil decreases from 26%to 14%,while the contribution from the deep soil increases from 4%to 10%.Snow contributes over 20%of land FSC,especially over high *** six decades of CLM5 long-term simulations,it is revealed that the change of FSC in most basins is related to internal climate *** FSC of river basins which displays the proportion of precipitation retained on land is worthy of further attention regarding the predictability of water resources.

关键词： freshwater GRACE land surface model soil moisture climate variability storage capability

SIMULATION OF EXTRA LIGHT-THIN COMPONENT DEFORMATION WITH ABNORMAL SHAPE

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Chinese Journal of Mechanical Engineering 2005年第3期18卷 393-397页

作者： gu Lizhi xing Lei College of Mechatronics Engineering and Automation Huaqiao University Quanzhou 362021 China College of Mechanical Engineering Jiamusi University Jiamusi 154007 China

Based on the analyses of the structural feature and the function requirements of newstyle bottle cap, the two fundamental components, the lining washer and the outer body, are abstracted as a plate and a cylinder with thin wall respectively. For simulating the deformation of the lining washer under equiaxial pressure, the modified Lagrangian finite element analysis is applied on the 228 triangular elements. Under assembly pressure, the plastoelastic deformation of both the lining washer and the outer body are studied in terms of Tresca＇s yield criterion and the limitation of the plastic deformation is presented when the two components are assembled into one unit. For the production of this kind of bottle cover, experiments are carried out by carefully measuring the changes of the diameter of lining washer as well as that of the outer body. It is shown that results from the experiments have a good agreement with the theoretical calculation and the maximum value of the allowable pressure has successfully been used in the design of newly developed bottle cap production system.

关键词： Simulation New-style composite bottle cap Lining washer Load Plastic deformation

Underestimation of the Warming Trend over the Tibetan Plateau during 1998–2013 by Global Land Data Assimilation Systems and Atmospheric Reanalyses

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Journal of Meteorological Research 2020年第1期34卷 88-100页

作者： Peng JI xing yuan Key Laboratory of Regional Climate–Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029 College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049 School of Hydrology and Water Resources Nanjing University of Information Science&TechnologyNanjing 210044

Accurate surface air temperature(T2m)data are key to investigating eco-hydrological responses to global *** of sparse in-situ observations,T2m datasets from atmospheric reanalysis or multi-source observation-based land data assimilation system(LDAS)are widely used in research over alpine regions such as the Tibetan Plateau(TP).It has been found that the warming rate of T2m over the TP accelerates during the global warming slowdown period of 1998–2013,which raises the question of whether the reanalysis or LDAS datasets can capture the warming *** evaluating two global LDASs,five global atmospheric reanalysis datasets,and a high-resolution dynamical downscaling simulation driven by one of the global reanalysis,we demonstrate that the LDASs and reanalysis datasets underestimate the warming trend over the TP by 27%–86%during 1998–*** is mainly caused by the underestimations of the increasing trends of surface downward radiation and nighttime total cloud amount over the southern and northern TP,*** GLDAS2.0,ERA5,and MERRA2 reduce biases of T2m simulation from their previous versions by 12%–94%,they do not show significant improvements in capturing the warming *** WRF dynamical downscaling dataset driven by ERA-Interim shows a great improvement,as it corrects the cooling trend in ERA-Interim to an observation-like warming trend over the southern *** results indicate that more efforts are needed to reasonably simulate the warming features over the TP during the global warming slowdown period,and the WRF dynamical downscaling dataset provides more accurate T2m estimations than its driven global reanalysis dataset ERA-Interim for producing LDAS products over the TP.

关键词： land data assimilation system(LDAS) reanalysis datasets WRF dynamical downscaling Tibetan Plateau global warming slowdown

Effect of hydraulic retention time and pH on oxidation of ferrous iron in simulated ferruginous acid mine drainage treatment with inoculation of iron-oxidizing bacteria

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Water Science and Engineering 2019年第3期12卷 213-220页

作者： Jun-hui Fan xing-yu Liu Qi-yuan gu Ming-jiang Zhang Xue-wu Hu GRIMAT Engineering Institute Co. Ltd. Beijing 101407 China School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China

The effect of hydraulic retention time (HRT) and pH on the biooxidation of ferrous iron during simulated acid mine drainage (AMD) treatment was *** simulated AMD was highly acidic (pH 2.5), rich in iron (about 1700 mg/L) and copper (about 200 mg/L), and contained high concentrations of sulfate (about 4700 mg/L).The biooxidation of ferrous iron was studied in a laboratory-scale upflow packed bed bioreactor (PBR).The HRT was shortened stepwise from 40 h to 20 h, 13 h, and 8 h under the acidic environment at a pH value of ***, the influent pH value was changed from 2.2 to 1.2 at a constant suitable *** and microbial community structure analyses were performed on water samples and stuffing collected from the bioreactor under different *** results indicate that the efficiency of ferrous iron oxidation gradually decreased with the decrease of HRT, and when the HRT exceeded 13 h, ferrous iron in AMD was almost completely *** addition, the best efficiency of ferrous iron oxidation was achieved at the influent pH value of *** community structure analyses show that Leptospirillum is the predominant genus attached in the bioreactor, and low influent pH values are suitable for the growth of Leptospirillum.

关键词： Acid mine drainage Iron-oxidizing bacteria Biooxidation of ferrous iron Hydraulic retention time Influent pH Microbial community analyses

Transcriptional Regulation of Expression of the Maize Aldehyde Dehydrogenase 7 Gene (ZmALDH7B6) in Response to Abiotic Stresses

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Journal of Integrative Agriculture 2014年第9期13卷 1900-1908页

作者： AN Xia DUAN Feng-ying guO Song CHEN Fan-jun yuan Li-xing gu Ri-liang Department of Plant Nutrition Center for ResourcesEnvironment and Food SecurityChina Agricultural University

Aldehyde dehydrogenases（ALDHs） represent a large protein family, which includes several members that catalyze the oxidation of an aldehyde to its corresponding carboxylic acid in plants. Genes encoding members of the ALDH7 subfamily have been suggested to play important roles in various stress adaptations in plants. In this study, quantitative RT-PCR analysis revealed that a maize ALDH7 subfamily member（ZmALDH7B6） was constitutively expressed in various organs, including roots, leaves, immature ears, tassels, and developing seeds. The abundance of ZmALDH7B6 mRNA transcripts in maize roots was increased by ammonium, NaCl, and mannitol treatments. To further analyze tissue-specific and stress-induced expression patterns, the 1.5-kb 5′-flanking ZmALDH7B6 promoter region was fused to the β-glucuronidase（guS） reporter gene and introduced into maize plants. In roots of independent transgenic lines, there was significant induction of guS activity in response to ammonium supply, confirming ammonium-dependent expression of ZmALDH7B6 at the transcript level. Histochemical staining showed that guS activity driven by the ZmALDH7B6 promoter was mainly localized in the vascular tissues of maize roots. These results suggested that ZmALDH7B6 is induced by multiple environmental stresses in maize roots, and may play a role in detoxifying aldehydes, particularly in vascular tissue.

关键词： abiotic stress aldehyde dehydrogenase gene expression promoter transgenic maize

Advances in salinity tolerance of soybean: Genetic diversity, heredity, and gene identification contribute to improving salinity tolerance

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Journal of Integrative Agriculture 2018年第10期17卷 2215-2221页

作者： CHEN Hua-tao LIU Xiao-qing ZHANG Hong-mei yuan xing-xing gu He-ping CUI Xiao-yan CHEN Xin Institute of Industrial Crops Jiangsu Academy of Agricultural Sciences

Salt stress is one of the major abiotic stresses affecting soybean growth. Genetic improvement for salt tolerance is an effective way to protect soybean yield under salt stress conditions. Successful improvement of salt tolerance in soybean relies on identifying genetic variation that confers tolerance in soybean germplasm and subsequently incorporating these genetic resources into cultivars. In this review, we summarize the progress in genetic diversity and genetics of salt tolerance in soybean, which includes identifying genetic diversity for salt tolerant germplasm; mapping QTLs conferring salt tolerance; map-based cloning; and conducting genome-wide association study（GWAS） analysis in soybean. Future research avenues are also discussed, including high throughput phenotyping technology, the CRISPR/Cas9 Genome-Editing System, and genomic selection technology for molecular breeding of salt tolerance.

关键词： soybean genetic variation heredity gene identification salinity improvement

Surface diffraction beamline at the SSRF

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Nuclear Science and Techniques 2024年第7期35卷 47-57页

作者： Yue-Liang gu Xu Zheng xing-Min Zhang Bin Zhao guang-Zhi Yin Da-Ming Zhu yuan-He Sun xing-Yu Gao Xiao-Long Li Shanghai Advanced Research Institute Chinese Academy of Sciences239 Zhangheng RoadPudong DistrictShanghai201204China

BL02U2 of the Shanghai Synchrotron Radiation Facility is a surface diffraction beamline with a photon flux of 5.5×10^(12) photons/s at 10 keV and a beam size of 160µm×80µm at the sample *** is dedicated to studying surfaces(solid-vacuum,solid-gas)and interfaces(solid-solid,solid-liquid,and liquid-liquid)in nanoscience,condensed matter,and soft matter systems using various surface scattering techniques over an energy range of 4.8-28 keV with transmission and reflection ***,BL02U2 has a high energy resolution,high angular resolution,and low beam divergence,which can provide excellent properties for X-ray diffraction experiments,such as grazing incident X-ray diffraction,X-ray reflectivity,crystal truncation rods,and liquid X-ray *** of in situ environments can also be provided for the samples *** paper describes the setup of the new beamline and its applications in various fields.

关键词： Surface and interface Beamline Surface diffraction Microstructure

Synthesis and Characterization of Polyaniline/MgTiO_(3) Composite with Excellent Thermal and Electrochemical Performance

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Journal of Wuhan University of Technology(Materials Science) 2021年第5期36卷 730-736页

作者： JIN Yazhou xing Weiwei ZHAO Siyu gu Xiaojie CHI Liping yuan Meng XU Fen WANG Shaoxu College of Materials Science and Engineering Dalian Jiaotong UniversityDalian 116028China Dalian Eco-environmental Affairs Service Center Dalian 116028China guangxi Key Laboratory of Information Materials(guilin University of Electronic Technology) Guilin 541004China College of Environmental and Chemical Engineering Dalian Jiaotong UniversityDalian 116028China

This article explores the effects of doping ferroelectric materials MgTiO_(3) with different proportions on the properties of polyaniline(PANI).PANI/MgTiO_(3) composites were prepared by in-situ composite *** transform infrared spectroscopy(FTIR)and X-ray diffraction(XRD)were used to characterize the structure of the *** electron microscope(SEM)was used to characterize the morphology of the *** thermal stability of the composites was investigated by thermogravimetry(TG)and derivative thermogravimetry(DTG).Electrochemical methods(cyclic voltammetry(CV),electrochemical impedance spectroscopy(EIS),and constant current charge-discharge test)were used to compare and analyze the electrochemical performance of the ***-DTG analysis and electrochemical experiments all show that the thermal stability and electrochemical properties of the PANI/MgTiO_(3) composite with a mass ratio of 82/18(w/w)are the *** results indicate that there is a synergistic effect between PANI and MgTiO_(3),which improves the performances of the PANI when the appropriate amount of MgTiO_(3) is added.

关键词： PANI/MgTiO_(3)composites in-situ composite method thermal stability electrochemical performance

Two Types of Flash Drought and Their Connections with Seasonal Drought

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Advances in Atmospheric Sciences 2018年第12期35卷 1478-1490页

作者： Linying WANG xing yuan Key Laboratory of Regional Climate–Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of Sciences

Flash drought is a rapidly intensifying drought with abnormally high temperature,which has greatly threatened crop yields and water supply,and aroused wide public concern in a warming ***,the preferable hydrometeorological conditions for flash drought and its association with conventional drought at longer time scales remain ***,we investigate two types of flash drought over China:one is high-temperature driven(Type Ⅰ),while the other is water-deficit driven(Type Ⅱ).Results show that the frequencies of the two types of flash drought averaged over China during the growing season are *** I flash drought tends to occur over southern China,where moisture supply is sufficient,while Type Ⅱ is more likely to occur over semi-arid regions such as northern *** types of flash drought increase significantly(p<0.01)during 1979–2010,with a doubled rise in Type Ⅰ as compared with Type Ⅱ.Composite analysis shows that high temperature quickly increases evapotranspiration(ET)and reduces soil moisture from two pentads before the onset of Type Ⅰ flash *** contrast,there are larger soil moisture deficits two pentads before the onset of Type Ⅱ flash drought,leading to a decrease in ET and increase in *** flash drought associated with seasonal drought,there is a greater likelihood of occurrence during the onset and recovery phases of seasonal drought,suggesting perfect conditions for flash drought during transition *** study provides a basis for the early warning of flash drought by connecting multiscale drought phenomena.

关键词： flash drought climate change soil moisture evapotranspiration seasonal drought