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Study on Quantitative Precipitation Estimation by Polarimetric Radar Using Deep Learning

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Advances in Atmospheric Sciences 2024年第6期41卷 1147-1160页

作者： Jiang HUAngFU Zhiqun HU jiafeng ZHEng Lirong wAng Yongjie ZHU State Key Lab of Severe weather Chinese Academy of Meteorological SciencesBeijing 100081China Meteorological observatory of Jiangxi Province Nanchang 330096China Hebei Meteorological Disaster Prevention and Environmental Meteorological Center Shijiazhuang 050021China School of Atmospheric Sciences Chengdu University of Information TechnologyChengdu 610225China

Accurate radar quantitative precipitation estimation(QPE)plays an essential role in disaster prevention and *** this paper,two deep learning-based QPE networks including a single-parameter network and a multi-parameter network are ***,a self-defined loss function(SLF)is proposed during *** dataset includes Shijiazhuang S-band dual polarimetric radar(CINRAD/SAD)data and rain gauge data within the radar’s 100-km detection range during the flood season of 2021 in North *** that the specific propagation phase shift(KDP)has a roughly linear relationship with the precipitation intensity,KDP is set to 0.5°km^(-1 )as a threshold value to divide all the rain data(AR)into a heavy rain(HR)and light rain(LR)***,12 deep learning-based QPE models are trained according to the input radar parameters,the precipitation datasets,and whether an SLF was adopted,*** results suggest that the effects of QPE after distinguishing rainfall intensity are better than those without distinguishing,and the effects of using SLF are better than those that used MSE as a loss function.A Z-R relationship and a ZH-KDP-R synthesis method are compared with deep learning-based *** mean relative errors(MRE)of AR models using SLF are improved by 61.90%,51.21%,and 56.34%compared with the Z-R relational method,and by 38.63%,42.55%,and 47.49%compared with the synthesis ***,the models are further evaluated in three precipitation processes,which manifest that the deep learning-based models have significant advantages over the traditional empirical formula methods.

关键词： polarimetric radar quantitative precipitation estimation deep learning single-parameter network multi-parameter network

Experimental study on the membrane distillation of highly mineralized mine water

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International Journal of Coal Science & Technology 2021年第5期8卷 1025-1033页

作者： Ji Qi jiafeng Lv wei Bian Jingfeng Li Shuqin Liu School of Chemical and Environmental Engineering China University of Mining and TechnologyBeijing 100083China State Key Laboratory of water Resource Protection and Utilization in Coal Mining China Energy Investment CorporationBeijing 100011China

Membrane distillation(MD)is a promising membrane separation technique used to treat industrial *** coupled with cheap heat sources,MD has significant economic ***,MD can be combined with solar energy to realize the large-scale and low-cost treatment of highly mineralized mine water in the western coalproducing region of *** this study,highly mineralized mine water from the Ningdong area of China was subjected to vacuum MD(VMD)using polyvinylidene fluoride hollow-fiber *** optimal operation parameters of VMD were determined by response surface ***,the feasibility of VMD for treating highly mineralized mine water was *** fouling behavior observed during VMD was further investigated by scanning electron microscopy with energy-dispersive X-ray spectroscopy(SEM-EDS).Under the optimal parameters(pressure=-0.08 MPa,temperature=70℃,and feed flow rate=1.5 L/min),the maximum membrane flux was 8.85 kg/(m^(2) h),and the desalination rate was 99.7%.Membrane fouling could be divided into three stages:membrane wetting,crystallization,and fouling layer *** cleaning restored the flux and salt rejection rate to 94%and 97%of the initial values,respectively;however,the cleaning interval and cleaning efficiency decreased as the VMD run time ***-EDS analysis revealed that the reduction in flux was caused by the precipitation of CaCO_(3).The findings also demonstrated that the membrane wetting could be attributed to the formation of NaCl on the cross section and outer surface of the ***,the results confirm the feasibility of MD for treating mine water and provide meaningful guidance for the industrial application of MD.

关键词： Mine water Membrane distillation Operating parameters Membrane fouling

Dynamic modeling of a three-dimensional braided composite thin plate considering braiding directions

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 123-138页

作者： Chentong GAO Huiyu SUN Jianping GU w.M.HUAng College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics School of Mechanical and Aerospace Engineering Nanyang Technological University Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology School of Materials Science and EngineeringNanjing Institute of Technology

Currently, there are a limited number of dynamic models available for braided composite plates with large overall motions, despite the incorporation of three-dimensional(3D) braided composites into rotating blade components. In this paper, a dynamic model of 3D 4-directional braided composite thin plates considering braiding directions is established. Based on Kirchhoff's plate assumptions, the displacement variables of the plate are expressed. By incorporating the braiding directions into the constitutive equation of the braided composites, the dynamic model of the plate considering braiding directions is obtained. The effects of the speeds, braiding directions, and braided angles on the responses of the plate with fixed-axis rotation and translational motion, respectively, are investigated. This paper presents a dynamic theory for calculating the deformation of 3D braided composite structures undergoing both translational and rotational motions. It also provides a simulation method for investigating the dynamic behavior of non-isotropic material plates in various applications.

关键词： three-dimensional (3D) braided composite braiding direction composite thin plate large overall motion dynamic model O313.7

Emerging CoMn-LDH@MnO2 electrode materials assembled using nanosheets for flexible and foldable energy storage devices

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Journal of Energy Chemistry 2020年第6期29卷 67-73,I0003页

作者： Yue Zhao jiafeng He Meizhen Dai Depeng Zhao Xiang wu Baodan Liu School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870LiaoningChina Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016LiaoningChina

CoMn layered double hydroxides(CoMn-LDH)are promising electrode materials for supercapacitors because of their excellent cyclic ***,they possess relatively low *** this work,hybrid CoMn-LDH@MnO2 products grown on Ni foams were obtained through a facile hydrothermal *** as-synthesized samples employed as electrodes deliver a specific capacitance of 2325.01 F g^-1 at 1 A g^-*** assembled asymmetric supercapacitor using these products as positive electrodes shows a maximum energy density of 59.73 w h kg^-1 at 1000.09 w kg^-*** prominent electrochemical performance of the as-prepared electrodes could be attributes to hierarchical *** findings suggest that hybrid structures might be potential alternatives for future flexible energy storage devices.

关键词： CoMn-LDH@MnO2 electrode Specific capacitance Flexible device Cyclic stability

A genome-wide association study of early-maturation traits in upland cotton based on the CottonSNP8oK array

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Journal of Integrative Plant Biology 2018年第10期60卷 970-985页

作者： Chengqi Li Yuanyuanwang Nijiang Ai Yue Li jiafeng Song Collaborative Innovation Center of Modern Biological Breeding Henan Province/Cotton Research InstituteHenan Institute of Science andTechnologyXinxiang 453003China Shihezi Agricultural Science Research Institute Shihezi 832000China

Genome-wide association studies （GwASs） efficiently identify genetic loci controlling traits at a relatively high resolution. In this study, variations in major early-maturation traits, including seedling period （SP）, bud period （BP）, flower and boll period （FBP）, and growth period （GP）, of 169 upland cotton accessions were investigated, and a GwAS of early maturation was performed based on a CottonSNPSoK array. A total of 49,650 high-quality single-nucleotide polymorphisms （SNPs） were screened, and 29 significant SNPs located on chromosomes A6, A7, A8, D% D2, and D9, were repeatedly identified as associated with early-maturation traits, in at least two environments or two algorithms. Of these 29 significant SNPs, I, 12, 11, and 5 were related to SP, BP, FBP, and GP, respectively. Six peak SNPs, TM47967,TM13732, TM2o937, TM28428, TM5o283, and TM72552, exhibited phenotypic contributions of approximately lo%, which could allow them to be used for marker-assisted selection. One of these, TM72552, as well as four other SNPs, TM72554, TM72555, TM72558, and TM72559, corresponded to the quantitative trait loci previously reported. In total, 274 candidate genes were identified from the genome sequences of upland cotton and were categorized based on their functional annotations. Finally, our studies identified Gh_DoIGo34o and Gh_DoIGo34~ as potential candidate genes for improving cotton early maturity.

关键词： A genome-wide association study of early-maturation traits in upland cotton based on the CottonSNP8oK array

Existence of Positive Solutions for the Nonhomogeneous Schrodinger-Poisson System with Strong Singularity

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Journal of Partial Differential Equations 2021年第2期34卷 186-200页

作者： LIAO jiafeng CHEN Qingfang ZHU Lijun College of Mathematics Education China West Normal UniversityNanchong 637002China School of Mathematics and Information China West Normal UniversityNanchong 637002China

In this paper,a class of nonhomogeneous Schrodinger-Poisson systems with strong singularity are *** with the variational method and Nehari method,we obtain a positive solution for this system which improves the recent... 详细信息

关键词： Schrodinger-Poisson system strong singularity positive solution Nehari method

一类4维3-李代数上的O-算子及导出的3-Pre-李代数

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浙江师范大学学报（自然科学版） 2025年第1期48卷 21-29页

作者：程紫莹吕家凤亢闯闯浙江师范大学数学科学学院浙江金华321004

李代数的Operad理论应用于3-李代数,可自然地构造出3-Pre-李代数,其与Pre-李代数有很多相似的性质.利用4维复3-李代数的分类以及3-李代数和O-算子的结构常数的关系,使用Maple软件求解三次非线性方程组,对一类4维复3-李代数上与伴随表示... 详细信息

李代数的Operad理论应用于3-李代数,可自然地构造出3-Pre-李代数,其与Pre-李代数有很多相似的性质.利用4维复3-李代数的分类以及3-李代数和O-算子的结构常数的关系,使用Maple软件求解三次非线性方程组,对一类4维复3-李代数上与伴随表示相结合的O-算子进行了刻画.此外,利用所得结果,给出了这些O-算子导出的26个3-Pre-李代数的例子.

关键词： 3-Pre-李代数 O-算子 3-李代数 Pre-李代数

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The RNA Pol Ⅱ sub-complex hsRpb4/7 is required for viability of multiple human cell lines

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Protein & Cell 2012年第11期3卷 846-854页

作者： Yang Zhao Kim K.C.Li King Pan ng Chi Ho ng Kevin A.w.Lee Division of Life Science The Hong Kong University of Science and TechnologySai KungHong Kong S.A.R.China

The evolutionarily conserved RNA Polymerase Ⅱ Rpb4/7 sub-complex has been thoroughly studied in yeast and impacts gene expression at multiple levels including transcription,mRNA processing and *** addition Rpb4/7 exerts differential effects on gene expression in yeast and Rpb4 is not obligatory for yeast(***)*** roles for human(hs)Rpb4/7 have not been extensively described and we have probed this question by depleting hsRpb4/7 in established human cell lines using RNA *** find that Rpb4/7 protein levels are inter-dependent and accordingly,the functional effects of depleting either protein are ***4/7 exhibits gene-specific effects and cells initially remain viable upon hsRpb4/7 *** prolonged hsRpb4/7 depletion is cytotoxic in the range of cell lines *** cell death occurs by an unknown mechanism and in some cases is accompanied by a pronounced elongated cell *** conclusion we provide evidence for a gene-specific role of hsRpb4/7 in human cell viability.

关键词： RNA PolymeraseⅡ hsRpb4/7 sub-complex gene expression cell viability cell shape

Controlling phase transfer of molybdenum carbides by various metals for highly efficient hydrogen production

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Journal of Energy Chemistry 2021年第11期30卷 191-197,I0005页

作者： Xingtao Sun jiafeng Yu Xin Tong Meng Yang Jixin Zhang Jian Sun Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China

The α phase Mo carbide has been widely investigated recently for its high activity in hydrogen production from water gas shift (wGS) reaction. However, high loading of noble metals as well as high economic and environmental cost derived from high-temperature ammonification and carbonization process will lead to high cost of hydrogen production. Thus, the efficient controlling of phase transfer is promising. Herein, metals (Au, Pt, Rh, Cu) with a wide range of loadings were impregnated on flame spray pyrolysis (FSP) made MoO_(3) to produce Mo carbides by one-step carbonization. A breakthrough high metal-normalized hydrogen production rate of 213 mmol H2·gmetal^(-1)·s^(-1) was achieved on 0.025 wt% Rh/MoCx, which was much higher than Pt and Au based Mo carbides ever reported. The addition of trace Rh induced direct MoO_(3) transformation to high purity α-MoC_(1-x) in one-step carbonization instead of two-steps ammonification and carbonization process. In comparison to Rh, the addition of Pt, Au and Cu tend to transfer MoO_(3) into β-Mo2C at the same conditions. Besides, the one with 2 wt% Rh exhibited high stability in wGS reaction even at high temperature (300 ℃) due to its inhibition on carbides oxidation induced by H2O. we demonstrate that it is feasible to control phase transfer of Mo carbides even by trace amount of metals to simplify the production process of catalysts. The catalytic performance improved by Rh in aspects of both activity and stability provides a guide for producing more stable Mo carbides catalysts.

关键词： Mo carbides α-MoC1-x Stability wGS Hydrogen production