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NνDEx-100 conceptual design report

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Nuclear Science and Techniques 2024年第1期35卷 18-33页

作者： Xi-Guang Cao Yan-Long Chang Kai Chen Emilio Ciuffoli Li-Min Duan Dong-Liang Fang Chao-Song Gao Surja K.Ghorui Peng-Chong Hu Qiang Hu si-Yuan Huang Ze-Yu Huang Lei Lang Yu-Lan Li Zhi-Jie Li Tian-Yu Liang Jun Liu Chen-Gui Lu Fa-Tai Mai Yuan Mei Hao Qiu Xiang-Ming Sun Xiao-Xing Tang Hu-Lin Wang Qian-Ming Wang Le Xiao Mu-Yun Xiao Jian-Yu Xin Nu Xu Peng Yang yi-Chen Yang Zhen Yang Zong-Yang Yu Dong-Liang Zhang Jun-Wei Zhang Cheng-Xin Zhao Dou Zhu NνDEx-100 collaboration Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China Lanzhou University Lanzhou 730000China Central China Normal University Wuhan 430079China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China Lawrence Berkeley National Laboratory BerkeleyCA 94720USA North China University of water resources and Electric Power Zhengzhou 450045China 不详

Observing nuclear neutrinoless double beta (0vββ) decay would be a revolutionary result in particle *** such a decay would prove that the neutrinos are their own antiparticles,help to study the absolute mass of neutrinos,explore the origin of their mass,and may explain the matter-antimatter asymmetry in our universe by lepton number *** propose developing a time projection chamber (TPC) using high-pressure ^(82)SeF_(6) gas and Topmetal silicon sensors for readout in the China Jinping Underground Laboratory (CJPL) to search for neutrinoless double beta decay of82Se,called the NvDEx *** being located at CJPL with the world’s thickest rock shielding,NvDEx combines the advantages of the high Qββ(2.996 MeV) of82Se and the TPC’s ability to distinguish signal and background events using their different topological *** makes NvDEx unique,with great potential for low-background and high-sensitivity 0 vββ***-100,a NvDEx experiment phase with 100 kg of SeF_(6)gas,is being built,with plans to complete installation at CJPL by *** report introduces 0 vββ physics,the NvDEx concept and its advantages,and the schematic design of NvDEx-100,its subsystems,and background and sensitivity estimation.

关键词： Neutrinoless double beta decay Time projection chamber ^(82)SeF_(6) China Jinping Underground Laboratory

Fractal model of spontaneous imbibition in low-permeability reservoirs coupled with heterogeneity of pore seepage channels and threshold pressure

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Petroleum Science 2024年第2期21卷 1002-1017页

作者： Ming-Sheng Zuo Hao Chen Xi-Liang Liu Hai-Peng Liu yi Wu Xin-Yu Qi National Key Laboratory of Petroleum resources and Engineering China University of Petroleum(Beijing)Beijing102249China College of Safety and Ocean Engineering China University of Petroleum(Beijing)Beijing102249China

Spontaneous imbibition(si)is an important mechanism for enhancing oil recovery in low-permeability *** to the strong heterogeneity,and the non-Darcy flow,the construction of si model for lowpermeability reservoirs is extremely ***,traditional si models based on single or averaged capillary tortuosity ignore the influence of heterogeneity of pore seepage channels and the threshold pressure(TP)on ***,in this work,based on capillary model and fractal theory,a mathematical model of characterizing si considering heterogeneity of pore seepage channels is *** this basis,the threshold pressure was introduced to determine the pore radius at which the wetted phase can displace *** proposed new si model was verified by imbibition experimental *** study shows that for weakly heterogeneous cores with permeability of 0-1 m D,the traditional si model can characterize the imbibition process relatively accurately,and the new imbibition model can increase the coefficient of determination by 1.05 ***,traditional model has serious deviations in predicting the imbibition recovery for cores with permeability of 10-50 m *** new si model coupling with heterogeneity of pore seepage channels and threshold pressure effectively solves this problem,and the determination coefficient is increased from 0.344 to 0.922,which is increased by2.68 *** low-permeability reservoirs,the production of the oil in transitional pores(0.01-0.1μm)and mesopores(0.1-1μm)significantly affects the imbibition recovery,as the research shows that when the heterogeneity of pore seepage channels is ignored,the oil recovery in transitional pores and mesopores decreases by 7.54%and 4.26%,*** analysis shows that increasing interfacial tension,decreasing contact angle,oil-water viscosity ratio and threshold pressure will increase imbibition *** addition,there are critical values for the influence of these factors o

关键词： Spontaneous imbibition Low-permeability reservoir Fractal model Threshold pressure Capillary tube

Effect of freeze-thaw cycles on mechanical behavior of clay-gravel mixtures

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Journal of Mountain Science 2022年第12期19卷 3615-3626页

作者： ZHANG Yong-gan LIU si-hong DENG Gang FANG Bin-xin ZHANG Yan-yi LU Yang College of water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China Key Laboratory of Construction and Safety of water Engineering of the Ministry of water resources China Institute of Water Resources and Hydropower ResearchBeijing 100048China

The use of clay-gravel mixtures(i.e.,adding excavated or natural gravel particles into clay soil matrix)as the main filling materials is increasing in the anti-seepage system of high Earth Core Rockfill Dams(ECRDs).With the continuous construction of high ECRDs in the Chinese plateaus and cold regions,it is of great urgency and importance to understand the physical and mechanical characteristics of compacted clay-gravel mixtures under freeze-thaw *** this end,laboratory freezing-thawing tests,computed tomography(CT),and triaxial compression tests were conducted to evaluate the effects of freezethaw cycles on moisture loss,pore structure characteristics,stress-strain behavior,failure strength,elastic modulus,cohesion,and internal friction angle of compacted clay-gravel *** results demonstrate that,1)the freeze-thaw cycle significantly changed the mechanical characteristics of the clay-gravel mixture samples,but the shape of the stress-strain curve is less sensitive to it.2)The failure strength of samples exhibits a significant decrease after the first freeze-thaw cycle,but shows a certain increase as the number of freeze-thaw cycles increases from 1 to 2.3)The elastic modulus of samples first decreases and then increases with increasing freeze-thaw cycle,and the most severe deterioration was observed after the first freeze-thaw cycle.4)Regardless of the number of freeze-thaw cycles,there is a linear relationship between failure strength and elastic modulus for a sample that has suffered freeze-thaw weathering.5)The cohesion of samples decreases firstly and then slightly increases with increasing freeze-thaw cycles,while the internal friction angle is hardly affected.

关键词： Earth core rockfill dam Clay-gravel mixtures Freeze-thaw cycles Computed tomography Mechanical behavior

NUMERICAL MODELLING OF BORES DUE TO DAM-BREAK

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Journal of Hydrodynamics 1991年第2期3卷 5-12页

作者： Hu, si-yi Tan, Wei-yan Nanjing Research Inst of Hydrology and Water Resources Nanjing China

In this paper TVD explicit schemes developed recently in CFD are used to simulate five models of bores due to dam-break. Numerical experiments are presented to demonstrate that they achieve high resolution and generat... 详细信息

关键词： Dams Gas Dynamics Hydrodynamics Mathematical Techniques Numerical Methods water Waves

Syntheses and properties of associative acrylamide copolymers containing short hydrophobic chains used in a friction reducer for slick-water fracturing

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Petroleum Science 2024年第3期21卷 1889-1901页

作者： Ya-Xing Dai Xian-Li Zhang si-Yuan Liu Feng-Run-Ze Zhang yi-Xi Zhang Yu-Tong Sang Jing-Xi Zheng Zhao-Sheng Liu Peng Zhang College of Chemistry and Chemical Engineering Chongqing University of Science and TechnologyChongqing401331China College of Ecology and Environment Chongqing Resources and Environmental Protection of UniversityChongqing401331China China China Property Project Department of Dezhou Mining Property Service CenterShengli Oilfield Company of SinopecDezhou253000ShandongChina

Two allyldimethylalkyl quaternary ammonium salt(AQAS)monomers,N,N-dimethylallylphenylpropylammonium bromide(AQAS1)and N,N-dimethylallylnonylammonium bromide(AQAS2),were synthesized and used to prepare modified polyacrylamide *** new drag reducers were synthesized from acrylamide(AM),sodium acrylate(Na AA)and a cationic modified monomer(AQAS1 or AQAS2)via aqueous solution polymerization,and the copolymers were named P(AM/Na AA/AQAS1)and P(AM/Na AA/AQAS2),*** structures of the drag reduction agents were confirmed by IR and1H NMR *** molecular weight(Mw)of P(AM/Na AA/AQAS1)was 1.79×10^(6)g/*** the copolymer concentration was 1000 mg/L and the flow rate was 45 L/min,in fresh water the highest drag reduction rate was 75.8%,in 10,000 mg/L Na Cl solution the drag reduction rate decreased to 72.9%.The molecular weight of P(AM/Na AA/AQAS2)was 3.17×10^(6)g/*** the copolymer concentration was500 mg/L and the flow rate was 45 L/min,the drag reduction rate reached 75.2%,and in 10,000 mg/L Na Cl solution the drag reduction rate was 73.3%,decreased by approximately 1.9%.The drag reduction rate for partially hydrolyzed polyacrylamide(HPAM)was also investigated,and the results showed that the drag reduction rates for 500 and 1000 mg/L HPAM solutions were merely 43.2%and 49.0%in brine,*** with HPAM,both of the above copolymers presented better drag reduction capacities.

关键词： Shale gas Slick water Drag reducer Modified monomer Copolymerization

Two-dimensional numerical simulation of sediment transport using improved critical shear stress methods

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International Journal of Sediment Research 2020年第1期35卷 15-26页

作者： Zhiyong Feng Guangming Tan Junqiang Xia Caiwen shu Peng Chen Ran yi State Key Laboratory of water resources and Hydropower Engineering Science Wuhan University Key Laboratory of water Project Ecological Effect and Ecological Restoration Institute of HydroecologyMinistry of Water Resources and Chinese Academy of Sciences

Research on the critical shear stresses for erosion and deposition for cohesive sediment has attracted substantial attention from both engineering and theoretical viewpoints due to their importance in sediment transport *** studies have proposed a large number of empirical and semiempirical methods to estimate the critical erosion and deposition shear stress,but comparative analyses and validation of the existing methods are still lacking,leaving questions regarding the applicability ranges of the *** current paper evaluates the performance and applicability range of five critical erosion shear stress methods derived from different hypotheses on sediment transport for flume experiments and natural tidal rivers using a process-based *** addition,the effect of the critical deposition shear stress on sediment transport is *** results show that the different critical erosion shear stress methods yield distinctly different prediction results,and their performance and applicability ranges are discussed by comparing their predictions with measured sediment concentrations from the Shenzhen river and measured geometric changes from the Partheniades’ flume *** hiding and exposure effect has been recognized as a crucial factor in the incipient motion of sediment on nonuniform beds.A sensitivity analysis of selective deposition and continuous deposition justifies the existence of the critical deposition shear *** current study highlights the performance and applicability ranges of the existing critical shear stress methods in sediment transport modeling for uniform and nonuniform beds,which will enrich understanding of the underlying mechanisms of erosion and deposition of cohesive sediment.

关键词： Cohesive sediment Critical shear stress Hiding and exposure effect Numerical modeling Shenzhen river

Outlier Detection for water Supply Data Based on Joint Auto-Encoder

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Computers, Materials & Continua 2020年第7期64卷 541-555页

作者： shu Fang Lei Huang yi Wan Weize Sun Jingxin Xu Guangdong Laboratory of Artificial-Intelligence and Cyber-Economics(SZ) College of Electronics and Information EngineeringShenzhen UniversityShenzhen518061China water resources Management Center of Ministry of water resources BeijingChina Departmet of Housing and Public Works QueenslandAustralia

With the development of science and technology,the status of the water environment has received more and more *** this paper,we propose a deep learning model,named a Joint Auto-Encoder network,to solve the problem of outlier detection in water supply *** Joint Auto-Encoder network first expands the size of training data and extracts the useful features from the input data,and then reconstructs the input data effectively into an *** outliers are detected based on the network’s reconstruction errors,with a larger reconstruction error indicating a higher rate to be an *** water supply data,there are mainly two types of outliers:outliers with large values and those with values closed to *** set two separate thresholds,and,for the reconstruction errors to detect the two types of outliers *** data samples with reconstruction errors exceeding the thresholds are voted to be *** two thresholds can be calculated by the classification confusion matrix and the receiver operating characteristic(ROC)*** have also performed comparisons between the Joint Auto-Encoder and the vanilla Auto-Encoder in this paper on both the synthesis data set and the MNIST data *** a result,our model has proved to outperform the vanilla Auto-Encoder and some other outlier detection approaches with the recall rate of 98.94 percent in water supply data.

关键词： water supply data outlier detection auto-encoder deep learning

A simulation of winter wheat crop responses to irrigation management using CERES-Wheat model in the North China Plain

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Journal of Integrative Agriculture 2018年第5期17卷 1181-1193页

作者： ZHOU Li-li LIAO shu-hua WANG Zhi-min WANG Pu ZHANG ying-hua YAN Hai-jun GAO Zhen SHEN si LIANG Xiao-gui WANG Jia-hui ZHOU shun-li College of water resources & Civil Engineering China Agricultural University College of Agronomy & Biotechnology China Agricultural University

To improve efficiency in the use of water resources in water-limited environments such as the North China Plain（NCP）, where winter wheat is a major and groundwater-consuming crop, the application of water-saving irrigation strategies must be considered as a method for the sustainable development of water resources. The initial objective of this study was to evaluate and validate the ability of the CERES-Wheat model simulation to predict the winter wheat grain yield, biomass yield and water use efficiency（WUE） responses to different irrigation management methods in the NCP. The results from evaluation and validation analyses were compared to observed data from 8 field experiments, and the results indicated that the model can accurately predict these parameters. The modified CERES-Wheat model was then used to simulate the development and growth of winter wheat under different irrigation treatments ranging from rainfed to four irrigation applications（full irrigation） using historical weather data from crop seasons over 33 years（1981–2014）. The data were classified into three types according to seasonal precipitation：〈100 mm, 100–140 mm, and 〉140 mm. Our results showed that the grain and biomass yield, harvest index（HI） and WUE responses to irrigation management were influenced by precipitation among years, whereby yield increased with higher precipitation. Scenario simulation analysis also showed that two irrigation applications of 75 mm each at the jointing stage and anthesis stage（T3） resulted in the highest grain yield and WUE among the irrigation treatments. Meanwhile, productivity in this treatment remained stable through different precipitation levels among years. One irrigation at the jointing stage（T1） improved grain yield compared to the rainfed treatment and resulted in yield values near those of T3, especially when precipitation was higher. These results indicate that T3 is the most suitable irrigation strategy under variable precipitation regimes for stabl

关键词： crop simulation modeling deficit irrigation precipitation level CERES-Wheat model winter wheat North China Plain

Gravity Wave Activity and Stratosphere-Troposphere Exchange During Typhoon Molave(2020)

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Journal of Tropical Meteorology 2024年第3期30卷 306-326页

作者： HUANG Dong WAN Ling-feng WAN yi-shun CHANG shu-jie MA Xin ZHAO Kai-jing College of Ocean and Meteorology/South China Sea Institute of Marine Meteorology/Laboratory for Coastal Ocean Variation and Disaster Prediction/Key Laboratory of Climate Resources and Environment in Continental Shelf Sea and Deep Sea(LCRE)/Key Laboratory of Space Ocean Remote Sensing and ApplicationMinistry of Natural ResourcesGuangdong Ocean UniversityZhanjiangGuangdong 524088 China Frontier Science Center for Deep Ocean Multispheres and Earth System(DOMES) Institute for Advanced Ocean Study(IAOS)Ocean University of ChinaQingdaoShandong 266100 China School of Earth and Environment University of LeedsLeeds LS29JT UK Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030 China

To investigate the stratosphere-troposphere exchange(STE)process induced by the gravity waves(GWs)caused by Typhoon Molave(2020)in the upper troposphere and lower stratosphere,we analyzed the ERA5 reanalysis data provided by the European Centre for Medium-Range Weather Forecasts and the CMA Tropical Cyclone Best Track *** also adopted the mesoscale forecast model Weather Research and Forecasting model V4.3 for numerical *** of the previous studies were about typhoon-induced STE and typhoon-induced GWs,while our research focused on the STE caused by typhoon-induced gravity *** analysis shows that most of the time,the gravity wave signal of Typhoon Molave appeared below the *** was stronger on the east side of the typhoon center(10°-20°N,110°-120°E)than on the west side,suggesting an eastward tilted structure with height *** the GWs in the upper troposphere and lower stratosphere region on the west side of the typhoon center broke up,it produced strong turbulence,resulting in stratosphere-troposphere *** this time,the average potential vorticity vertical flux increased with the average ozone mass mixing *** gravity wave events and STE process simulated by the WRF model were basically consistent with the results of ERA5 reanalysis data,but the time of gravity wave breaking was *** study indicates that after the breaking of the GWs induced by typhoons,turbulent mixing will also be generated,and thus the STE.

关键词： gravity wave typhoon stratosphere-troposphere exchange STE upper troposphere and lower stratosphere UTLS