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Study of Seismic P Wave in Mesoscale Fracture-Induced Arbitrary Anisotropic Media

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Journal of Earth Science 2024年第2期35卷 717-721页

作者： Han Xiao Xinmin Shang Zhentao Wang Xiping Wang Geophysical research Institute SINOPEC Shengli Oilfield CompanyShandong 257022China Working station for postdoctoral Scientific research Shengli OilfieldShandong 257000China

Mesoscale fracture controls the permeability of shale res ervoirs,it is one of the main research objectives of natural frac *** length of the mesoscale fracture is less than 1/4 of the seismic eigen wavelength and greater than 1%of the seis mic eigen wavelength,they cannot be identified in actual seis mic data and are usually displayed by the azimuthal anisotropy of seismic *** this paper,we propose a calculation process from fracture properties to seismic P-wave velocity and traveltime in anisotropic media induced by multiple sets of arbitrary occurring mesoscale *** on this process,the variations of the media’s Anisotropic(A-)parameters with fracture properties are ***,variation of P-wave NMO elliptical principle axis with the relative fracture density is studied according to the arbitrary anisotropic theory based on A-parameters.

关键词： seismic mesoscale shale

High-Precision Flow Numerical Simulation and Productivity Evaluation of Shale Oil Considering Stress Sensitivity

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Fluid Dynamics & Materials Processing 2024年第10期20卷 2281-2300页

作者： Mingjing Lu Qin Qian Anhai Zhong Feng Yang Wenjun He Min Li Petroleum Engineering Technology research Institute of Shengli Oilfield SINOPECDongying257000China postdoctoral Scientific research Working station of Shengli Oilfield SINOPECDongying257000China

Continental shale oil reservoirs,characterized by numerous bedding planes and micro-nano scale pores,feature significantly higher stress sensitivity compared to other types of ***,research on suitable stress sensitivity characterization models is still *** this study,three commonly used stress sensitivity models for shale oil reservoirs were considered,and experiments on representative core samples were *** fitting and comparing the data,the“exponential model”was identified as a characterization model that accurately represents stress sensitivity in continental shale oil *** validate the accuracy of the model,a two-phase seepage mathematical model for shale oil reservoirs coupled with the exponential model was *** model was discretely solved using the finite volume method,and its accuracy was verified through the commercial simulator *** study evaluated the productivity of a typical horizontal well under different engineering,geological,and fracture *** results indicate that considering stress sensitivity leads to a 13.57%reduction in production for the same matrix ***,as the fracture half-length and the number of fractures increase,and the bottomhole flowing pressure decreases,the reservoir stress sensitivity becomes higher.

关键词： Shale oil horizontal wells Embedded Discrete Fracture Model(EDFM) stress sensitivity numerical simulation sensitivity analysis

Production Capacity Prediction Method of Shale Oil Based on Machine Learning Combination Model

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Energy Engineering 2024年第8期121卷 2167-2190页

作者： Qin Qian Mingjing Lu Anhai Zhong Feng Yang Wenjun He Min Li Petroleum Engineering Technology research Institute of Shengli Oilfield SINOPECDongying257000China postdoctoral Scientific research Working station of Shengli Oilfield SINOPECDongying257000China

The production capacity of shale oil reservoirs after hydraulic fracturing is influenced by a complex interplay involving geological characteristics,engineering quality,and well *** relationships,nonlinear in nature,pose challenges for accurate description through physical *** field data provides insights into real-world effects,its limited volume and quality restrict its *** this,numerical simulation models offer effective *** harness the strengths of both data-driven and model-driven approaches,this study established a shale oil production capacity prediction model based on a machine learning combination *** fracturing development data from 236 wells in the field,a data-driven method employing the random forest algorithm is implemented to identify the main controlling factors for different types of shale oil *** the combination model integrating support vector machine(SVM)algorithm and back propagation neural network(BPNN),a model-driven shale oil production capacity prediction model is developed,capable of swiftly responding to shale oil development performance under varying geological,fluid,and well *** results of numerical experiments show that the proposed method demonstrates a notable enhancement in R2 by 22.5%and 5.8%compared to singular machine learning models like SVM and BPNN,showcasing its superior precision in predicting shale oil production capacity across diverse datasets.

关键词： Shale oil production capacity data-driven model model-driven method machine learning

Optimization of a Pipeline-Type Savonius Hydraulic Turbine

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Fluid Dynamics & Materials Processing 2024年第5期20卷 1123-1146页

作者： Xiaohui Wang Kai Zhang Xiaobang Bai Senchun Miao Zanxiu Wu Jicheng Li School of Energy and Power Engineering Lanzhou University of TechnologyLanzhou730050China postdoctoral station of Civil Engineering Lanzhou University of TechnologyLanzhou730050China postdoctoral research station of Xinxiang Aviation Industry(Group)Co. Ltd.Xinxiang453000China Chongqing Pump Industry Co. Ltd.Chongqing404100China

This study focuses on a DN50 pipeline-type Savonius hydraulic *** torque variation of the turbine in a rotation cycle is analyzed theoretically in the framework of the plane potential flow *** numerical simulations show that the change in turbine torque is consistent with the theoretical analysis,with the main power zone and the secondary power zone exhibiting a positive *** contrast,the primary resistance zone and the secondary resistance zone are characterized by a negative *** relationships between the turbine’s internal flow angleθ,the deflector’s inclination angleα0,and the coverage angleαof the power zone are introduced,and a method for calculating the optimal number of blades is proposed to maximize the power *** are presented about performance tests conducted on five groups of hydraulic turbines with the blade number ranging from 3 to *** results indicate that both the turbine’s recovery power and efficiency attain the highest values when the blade number is 4,which is in agreement with the number of blades calculated by the proposed ***,the study examines the effects of the flow rate on turbine parameters and the projected energy generation and cost savings for a specific pipeline configuration.

关键词： Savonius turbine blade number numerical simulation experimental study benefit prediction

Dynamic analysis of major public health emergency transmission considering the dual-layer coupling of community–resident complex networks

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Chinese Physics B 2024年第7期33卷 158-169页

作者：杨鹏范如国王奕博张应青 School of Economics and Management Wuhan UniversityWuhan 430072China postdoctoral research station China International Engineering Consulting CorporationBeijing 100000China School of Business Administration Guizhou University of Finance and EconomicsGuiyang 550025China

We construct a dual-layer coupled complex network of communities and residents to represent the interconnected risk transmission network between communities and the disease transmission network among residents. It characterizes the process of infectious disease transmission among residents between communities through the SE2IHR model considering two types of infectors. By depicting a more fine-grained social structure and combining further simulation experiments, the study validates the crucial role of various prevention and control measures implemented by communities as primary executors in controlling the epidemic. research shows that the geographical boundaries of communities and the social interaction patterns of residents have a significant impact on the spread of the epidemic, where early detection, isolation and treatment strategies at community level are essential for controlling the spread of the epidemic. In addition, the study explores the collaborative governance model and institutional advantages of communities and residents in epidemic prevention and control.

关键词： propagation dynamics complex networks public health events community structure

Ultra-highly selective recognition of nucleosides over nucleotides by rational modification of tetralactam macrocycle and its application in enzyme assay

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Chinese Chemical Letters 2024年第6期35卷 274-278页

作者： Huan Yao Jian Qin Yan-Fang Wang Song-Meng Wang Liu-Huan Yi Shi-Yao Li Fangfang Du Liu-Pan Yang Li-Li Wang School of Pharmaceutical Science Postdoctoral Research Station of Basic MedicineHengyang Medical SchoolUniversity of South ChinaHengyang 421001China Department of Chemistry Southern University of Science and TechnologyShenzhen 518055China

Artificial macrocycle with high binding selectivity in water is often challenging but urgently needed in various research and application ***,we report a new water-soluble biomimetic tetralactam macrocycle and realize the ultra-high selectivity to nucleosides over corresponding monophosphate nucleotides by rational *** introduction of charged groups at the periphery of endofunctionalized cavity makes the selectivity(guanosine to guanosine 5-monophosphate)increase remarkably from 100 to *** on the ultra-high selectivity of biomimetic tetralactam macrocycle,the sensitive CD73 enzyme activity assay was then achieved through product-selective fluorescence indicator displacement ***,the capability of the proposed method for inhibitor screening was successfully displayed.

关键词： Rational modification Biomimetic macrocycle Ultra-high selectivity Enzyme assay

Damage Mechanism of Ultra-thin Asphalt Overlay(UTAO) based on Discrete Element Method

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Journal of Wuhan University of Technology(Materials Science) 2024年第2期39卷 473-486页

作者：杜晓博 GAO Liang RAO Faqiang 林宏伟 ZHANG Hongchao SUN Mutian XU Xiuchen postdoctoral station of Mechanical Engineering Tongji UniversityShanghai 201804China Guangzhou Daguang Expressway Co. LtdGuangzhou 510075China Key Laboratory of Road and Traffic Engineering of Ministry of Education Tongji UniversityShanghai 201804China

Aiming to analyze the damage mechanism of UTAO from the perspective of meso-mechanical mechanism using discrete element method(DEM),we conducted study of diseases problems of UTAO in several provinces in China,and found that aggregate spalling was one of the main disease types of UTAO.A discrete element model of UTAO pavement structure was constructed to explore the meso-mechanical mechanism of UTAO damage under the influence of layer thickness,gradation,and bonding *** experimental results show that,as the thickness of UTAO decreasing,the maximum value and the mean value of the contact force between all aggregate particles gradually increase,which leads to aggregates more prone to *** with OGFC-5 UTAO,AC-5 UTAO presents smaller maximum and average values of all contact forces,and the loading pressure in AC-5 UTAO is fully diffused in the lateral *** addition,the increment of pavement modulus strengthens the overall force of aggregate particles inside UTAO,resulting in aggregate particles peeling off more *** increase of bonding modulus changes the position where the maximum value of the tangential force appears,whereas has no effect on the normal force.

关键词： ultra-thin asphalt overlay pavement distress discrete element method meso-mechanics damage mechanism

Distributed power conditioning unit of large-scale space solar power station

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Chinese Journal of Aeronautics 2024年第8期37卷 421-434页

作者： Xintong LI Jianwei MI Yiqun ZHANG Guanheng FAN Jie DU School of Mechano-electronic Engineering Xidian UniversityXi’an 710071China Shaanxi Key Laboratory of Space Solar Power station System Xidian UniversityXi’an 710071China Academy of Advanced Interdisciplinary research Xidian UniversityXi’an 710071China

In this paper,a multi-bus distributed Power Conditioning Unit(PCU)is proposed for the Space Solar Power station with large scale photovoltaic(PV)array and power levels reaching MW *** this unit,there are multiple independent PV *** each PV array,there are multiple independent PV *** this paper,a V-P droop control method with adaptive droop coefficient is proposed,which modifies the droop intercept based on the bus voltage deviation and the power per unit value of the PV *** method ensures the accuracy of bus voltage and achieves proportional distribution of power between PV arrays based on the proposed topology structure in this *** the load changes or the output power of the PV array fluctuates,this method can ensure that power is distributed *** principle and control method of the proposed droop control method is analyzed in this *** effectiveness of the method is verified through MATLAB/Simulink simulation and *** and experimental results show that the proposed method can achieve power distributed proportionally when load changes and PV output power fluctuates,reduce bus voltage error caused by line impedance and differences in rated power of different PV arrays,and improve the performance of PV power generation system applied to space.

关键词： Space Solar Power station Photovoltaics Droop control DC confluence Power conditioning unit

Mycorrhizal fungi mitigate nitrogen losses of an experimental grassland by facilitating plant uptake and soil microbial immobilization

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Pedosphere 2024年第2期34卷 399-410页

作者： Yangyang JIA Marcel G.A.VAN DER HEIJDEN Alain Y.VALZANO-HELD Markus JOCHER Florian WALDER postdoctoral Mobile station of Ecology College of Ecology and EnvironmentXinjiang UniversityÜrümqi 830046China research Group Plant-Soil Interactions AgroscopeZürich 8046Switzerland research Group Climate and Agriculture AgroscopeZürich 8046Switzerland Department of Plant and Microbial Biology University of ZürichZürich 8008Switzerland research Group Soil Quality and Soil Use AgroscopeZürich 8046Switzerland

Nitrogen(N)is one of the most limited nutrients of terrestrial ecosystems,whose losses are prevented in tightly coupled cycles in finely tuned *** change-induced N enrichment through atmospheric deposition and application of vast amounts of fertilizer are now challenging the terrestrial N *** mycorrhizal fungi(AMF)are known drivers of plant-soil nutrient fluxes,but a comprehensive assessment of AMF involvement in N cycling under global change is still ***,we simulated N enrichment by fertilization(low/high)in experimental grassland microcosms under greenhouse conditions in the presence or absence of AMF and continuously monitored different N pathways over nine *** found that high N enrichment by fertilization decreased the relative abundance of legumes and the plant species dominating the plant community changed from grasses to forbs in the presence of AMF,based on aboveground *** presence of AMF always maintained plant N:phosphorus(P)ratios between 14 and 16,no matter how the soil N availability *** in plant N:P ratios due to the increased plant N and P uptake might thus be a primary pathway of AMF altering plant community ***,we constructed a comprehensive picture of AMF’s role in N cycling,highlighting that AMF reduced N losses primarily by mitigating N leaching,while N_(2)O emissions played a marginal *** mycorrhizal fungi reduced N_(2)O emissions directly through the promotion of N_(2)O-consuming *** underlying mechanism for reducing N leaching is mainly the AMF-mediated improved nutrient uptake and AMF-associated microbial *** results indicate that synergies between AMF and other soil microorganisms cannot be ignored in N cycling and that the integral role of AMF in N cycling terrestrial ecosystems can buffer the upcoming global changes.

关键词： N cycling N enrichment N uptake N:P ratio plant community structure symbiotic soil fungi