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Study on the clogging mechanism of punching screen in sand control by the punching structure parameters

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Petroleum Science 2024年第1期21卷 609-620页

作者： Fu-Cheng deng Fu-Lin Gui Bai-Tao fan Lei Wen Sheng-Hong Chen Ning Gong Yun-Chen Xiao Zhi-Hui Xu Yangtze University Jingzhou434023HubeiChina CNOOC Research Institute Ltd. Beijing100028China CNOOC Ener Tech-Drilling&Production Co. Tianjin300457China Tianjin Branch of CNOOC Ltd. Tianjin300459China

As an independent sand control unit or a common protective shell of a high-quality screen,the punching screen is the outermost sand retaining unit of the sand control pipe which is used in geothermal well or oil and gas ***,most screens only consider the influence of the internal sand retaining medium parameters in the sand control performance design while ignoring the influence of the plugging of the punching screen on the overall sand retaining performance of the *** explore the clogging mechanism of the punching screen,this paper established the clogging mechanism calculation model of a single punching screen sand control unit by using the computational fluid mechanics-discrete element method(CFD-DEM)combined *** to the combined motion of particles and fluids,the influence of the internal flow state on particle motion and accumulation was *** results showed that(1)the clogging process of the punching sand control unit is divided into three stages:initial clogging,aggravation of clogging and stability of *** the initial stage of blockage,coarse particles form a loose bridge structure,and blockage often occurs preferentially at the streamline gathering place below chamfering inside the sand control *** the stage of blockage intensification,the particle mass develops into a relatively complete sand bridge,which develops from both ends of the opening to the center of the *** the stable plugging stage,the sand deposits show a“fan shape”and form a“V-shaped”gully inside the punching slot element.(2)Under a certain reservoir particle-size distribution,The slit length and opening height have a large influence on the permeability and blockage rate,while the slit width size has little influence on the permeability and blockage *** microscopic clogging mechanism and its law of the punching screen prevention unit are proposed in this study,which has some field guidance significance for the design of punching screen

关键词： Punching screen Plugging CFD-DEM Size parameter Sand control

The Short-Term Prediction ofWind Power Based on the Convolutional Graph Attention Deep Neural Network

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Energy Engineering 2024年第2期121卷 359-376页

作者： fan Xiao Xiong ping Yeyang Li Yusen Xu Yiqun Kang Dan Liu Nianming Zhang State Grid Hubei Electric Power Research Institute Wuhan430077China College of Energy and Electrical Engineering Hohai UniversityNanjing210098China

The fluctuation of wind power affects the operating safety and power consumption of the electric power grid and restricts the grid connection of wind power on a large ***,wind power forecasting plays a key role in improving the safety and economic benefits of the power *** paper proposes a wind power predicting method based on a convolutional graph attention deep neural network with multi-wind farm *** on the graph attention network and attention mechanism,the method extracts spatial-temporal characteristics from the data of multiple wind ***,combined with a deep neural network,a convolutional graph attention deep neural network model is ***,the model is trained with the quantile regression loss function to achieve the wind power deterministic and probabilistic prediction based on multi-wind farm spatial-temporal data.A wind power dataset in the *** taken as an example to demonstrate the efficacy of the proposed *** with the selected baseline methods,the proposed model achieves the best prediction *** point prediction errors(i.e.,root mean square error(RMSE)and normalized mean absolute percentage error(NMAPE))are 0.304 MW and 1.177%,*** the comprehensive performance of probabilistic prediction(i.e.,con-tinuously ranked probability score(CRPS))is ***,the significance of multi-wind farm data and spatial-temporal feature extraction module is self-evident.

关键词： Format wind power prediction deep neural network graph attention network attention mechanism quantile regression

Clinical nursing value of predictive nursing in reducing complications of pregnant women undergoing short-term massive blood transfusion during cesarean section

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World Journal of Clinical Cases 2024年第1期12卷 51-58页

作者： Li Cheng Li-ping Li Yuan-Yuan Zhang fang deng Ting-Ting Lan Department of Obstertrics Wuhan Third HospitalWuhan 430000Hubei ProvinceChina Department of Gynaecology Wuhan No.1 HospitalWuHan 430030Hubei ProvinceChina Center for Reproductive Medicine Department of Obstetrics and GynecologySichuan Provincial People's HospitalSchool of MedicineUniversity of Electronic Science and Technology of ChinaChengdu 610072Sichuan ProvinceChina

BACKGROUND Cesarean hemorrhage is one of the serious complications,and short-term massive blood transfusion can easily cause postoperative infection and physical stress ***,predictive nursing intervention has important clinical significance for *** To explore the effect of predictive nursing intervention on the stress response and complications of women undergoing short-term mass blood transfusion during cesarean section(CS).METHODS A clinical medical record of 100 pregnant women undergoing rapid mass blood transfusion during sections from June 2019 to June *** to the different nursing methods,patients divided into control group(n=50)and observation group(n=50).Among them,the control group implemented routine nursing,and the observation group implemented predictive nursing intervention based on the control ***,compared the differences in stress res-ponse,complications,and pain scores before and after the nursing of pregnant women undergoing rapid mass blood transfusion during *** The anxiety and depression scores of pregnant women in the two groups were significantly improved after nursing,and the psychological stress response of the observation group was significantly lower than that of the control group(P<0.05).The heart rate and mean arterial pressure(MAP)of the observation group during delivery were lower than those of the control group,and the MAP at the end of delivery was lower than that of the control group(P<0.05).Moreover,different pain scores improved significantly in both groups,with the observation group considerably less than the control group(P<0.05).After nursing,complications such as skin rash,urinary retention,chills,diarrhea,and anaphylactic shock in the observation group were 18%,which significantly higher than in the control group(4%)(P<0.05).CONCLUSION Predictive nursing intervention can effectively relieve the pain,reduce the incidence of complications,improve mood and stress response,and serve as a

关键词： Predictive care Rapid mass blood transfusion Cesarean section Stress response Complications

Miniature tunable Airy beam optical meta-device

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Opto-Electronic Advances 2024年第2期7卷 5-12页

作者： Jing Cheng Zhang Mu Ku Chen Yubin fan Qinmiao Chen Shufan Chen Jin Yao Xiaoyuan Liu Shumin Xiao Din ping Tsai Department of Electrical Engineering City University of Hong KongKowloonHong Kong SAR 999077China State Key Laboratory of Terahertz and Millimeter Waves City University of Hong KongKowloonHong Kong SAR 999077China Centre for Biosystems Neuroscienceand NanotechnologyCity University of Hong KongKowloonHong Kong SAR 999077China Ministry of Industry and Information Technology Key Lab of Micro-Nano Optoelectronic Information System Guangdong Provincial Key Laboratory of Semiconductor Optoelectronic Materials and Intelligent Photonic SystemsHarbin Institute of TechnologyShenzhen 518055China

Tunable Airy beams with controllable propagation trajectories have sparked interest in various fields,such as optical manipulation and laser *** research approaches encounter challenges related to insufficient compactness and integration feasibility,or they require enhanced tunability to enable real-time dynamic manipulation of the propagation *** this work,we present a novel method that utilizes a dual metasurface system to surpass these limitations,significantly enhancing the practical potential of the Airy *** approach involves encoding a cubic phase profile and two off-axis Fresnel lens phase profiles across the two *** validity of the proposed strategy has been confirmed through simulation and experimental *** proposed meta-device addresses the existing limitations and lays the foundation for broadening the applicability of Airy beams across diverse domains,encompassing light-sheet microscopy,laser fabrication,optical tweezers,etc.

关键词： metasurface miniature device tunable Airy beam tunable meta-device

Anisotropic shearing mechanism of Kangding slate:Experimental investigation and numerical analysis

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1487-1504页

作者： ping Liu Quansheng Liu Penghai deng Yucong Pan Yiming Lei Chenglei Du Xianqi Xie The Key Laboratory of Geotechnical and Structural Engineering Safety of Hubei Province School of Civil EngineeringWuhan UniversityWuhan430072China State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan430072China

The shear mechanical behavior is regarded as an essential factor affecting the stability of the surrounding rocks in underground *** shear strength and failure mechanisms of layered rock are significantly affected by the foliation *** shear tests were conducted on cubic slate samples with foliation angles of 0°,30°,45°,60°,and 90°.The effect of foliation angles on failure patterns,acoustic emission(AE)characteristics,and shear strength parameters was *** on AE characteristics,the slate failure process could be divided into four stages:quiet period,step-like increasing period,dramatic increasing period,and remission period.A new empirical expression of cohesion for layered rock was proposed,which was compared with linear and sinusoidal cohesion expressions based on the results made by this paper and previous *** comparative analysis demonstrated that the new expression has better prediction ability than other *** proposed empirical equation was used for direct shear simulations with the combined finite-discrete element method(FDEM),and it was found to align well with the experimental *** both computational efficiency and accuracy,it was recommended to use a shear rate of 0.01 m/s for FDEM to carry out direct shear *** balance the relationship between the number of elements and the simulation results in the direct shear simulations,the recommended element size is 1 mm.

关键词： Anisotropy Empirical expression of cohesion foliation angles Combined finite-discrete element method(FDEM) Shear rate Element size

Development of a high-repetition-rate lumped-inductance kicker magnet prototype for the beam switchyard of SHINE

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Nuclear Science and Techniques 2024年第2期35卷 20-31页

作者： Yong-fang Liu Rui-ping Wang Jin Tong Bo Zhang Si Chen Qi-Bing Yuan Hai-Xiao deng Ming Gu Bo Liu Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201412People’s Republic of China

The Shanghai high-repetition-rate X-ray free-electron laser and extreme light facility(SHINE)operates at a maximum repetition rate of 1 *** magnets are key components that distribute electron bunches into three different undulator lines in a bunch-by-bunch *** kicker field width must be less than the time interval between bunches.A lumpedinductance kicker prototype was developed using a vacuum chamber with a single-turn *** full magnetic field strength was 0.005 *** paper presents the requirements,design considerations,design parameters,magnetic field calculations,and measurements of the kicker *** relevant experimental results are also *** pulse width of the magnetic field was approximately 600 ns,and the maximum operation repetition rate was 1 *** developed kicker satisfies the requirements for the SHINE ***,numerous recommendations for the future optimization of kicker magnets are provided.

关键词： X-ray free-electron laser Kicker magnet Beam switchyard High repetition rate Ni-Zn ferrites

Numerical investigation on thermomechanical behavior of alumina–calcium hexaluminate refractories for purging plug

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Journal of Iron and Steel Research(International) 2024年第2期31卷 389-400页

作者： Li-ping Pan Ya-wei Li fang-guan Tan Yi-chen Chen Yang-fan Xu Zhu He Bao-kuan Li The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430081HubeiChina National-Provincial Joint Engineering Research Center of High Temperature Materials and Lining Technology Wuhan University of Science and TechnologyWuhan430081HubeiChina

Alumina–spinel refractories used in slit-type purging plugs are susceptible to cross-sectional damage,resulting in a serious mismatch between their service life and that of ***–calcium hexaluminate refractories have gradually become the new trend in purging plug materials with the development of refining *** thermomechanical damage of slit-type purging plugs with alumina–calcium hexaluminate refractory was investigated by the thermo-solid coupling *** with the polynomial fitting and design of experiments methods,the influence of thermophysical parameters on temperature and thermal stress of alumina–calcium hexaluminate refractories for purging plugs was systematically *** results show that the maximum thermal stress of the purging plugs appears during the stages of steel transporting and stirring,and the vulnerable parts are located above Y=0.323 *** thermal conductivity and the coefficient of thermal expansion of the material are the most sensitive parameters to the temperature and thermal stress inside the structure,*** addition of more calcium hexaluminate can relieve the stress concentration and large deformation around the ***,when the content of calcium hexaluminate is 47 wt.%and in the form of aggregate-binder,the temperature and thermal stress distribution inside the refractory are optimal,which can effectively improve the service life of the slit-type purging plug.

关键词： Purging plug Thermomechanical damage Refractory Design of experiments method Stress

Enhancing visible-light-driven NO oxidation through molecular‐level insights of dye-loaded sea sands

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Rare Metals 2024年第2期43卷 543-554页

作者： Yu-Han Li Bang-Fu Chen Sónia A.C.Carabineiro You-Yu Duan ping Tan Wing-Kei Ho fan Dong Engineering Research Center for Waste Oil Recovery Technology and Equipment Ministry of EducationChongqing Key Laboratory of Catalysis and New Environmental MaterialsChongqing Technology and Business UniversityChongqing400067China Nanchang Institute of Technology Nanchang33044China LAQV-REQUIMTE Department of ChemistryNOVA School of Science and TechnologyUniversidade NOVA de Lisboa2829-516CaparicaPortugal College of Physics and Center of Quantum Materials and Devices Chongqing UniversityChongqing401331China Department of Science and Environmental Studies The Education University of Hong KongHong Kong999077China

Natural minerals,abundant and easily obtained through simple physical processing,offer a cost-effective and environmentally friendly solution for dyeing wastewater disposal and air pollution *** study investigates the photocatalytic removal of NO using natural different types of dyes,loaded on natural sand,under visible light *** examining various coating concentrations of dyes and sand weights,we discovered that sand loaded with Rhodamine B(RhB)exhibits high activity for the photo-oxidation of NO.A combination results of X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),Fourier transform infrared spectroscopy(FTIR)and thermogravimetric(TG)analyses confirm the presence of SiO_(2),CaCO_(3),Al_(2)O_(3)and iron oxides as the main components of the ***,studying RhB-loaded individual components reveals that CaCO_(3)plays a crucial role in enhancing the NO removal *** results and theoretical calculations demonstrate the establishment of a directional charge transfer channel from CaCO_(3)to RhB,facilitating the adsorption and activation of molecular NO and O_(2).This work not only promotes the utilization of natural mineral resources but also enriches the fields of environmental photochemistry and semiconductor photocatalysis.

关键词： Sand dyes Rhodamine B Photo-oxidation of NO Visible light illumination

Interface optimization and defects suppression via Na F introduction enable efficient flexible Sb_(2)Se_(3) thin-film solar cells

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Journal of Energy Chemistry 2024年第3期90卷 165-175,I0006页

作者： Mingdong Chen Muhammad Ishaq Donglou Ren Hongli Ma Zhenghua Su ping fan David Le Coq Xianghua Zhang Guangxing Liang Shuo Chen Shenzhen Key Laboratory of Advanced Thin Films and Applications Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong ProvinceCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060GuangdongChina State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures MOE Key Laboratory of New Processing Technology for Nonferrous Metals and MaterialsSchool of ResourcesEnvironment and MaterialsGuangxi UniversityNanning 530004GuangxiChina CNRS ISCR(Institut des Sciences Chimiques de Rennes)UMR 6226Universitéde RennesRennes F-35000France

Sb_(2)Se_(3) with unique one-dimensional(1D) crystal structure exhibits exceptional deformation tolerance,demonstrating great application potential in flexible ***,the power conversion efficiency(PCE) of flexible Sb_(2)Se_(3) photovoltaic devices is temporarily limited by the complicated intrinsic defects and the undesirable contact ***,a high-quality Sb_(2)Se_(3) absorber layer with large crystal grains and benign [hkl] growth orientation can be first prepared on a Mo foil *** NaF intermediate layer is introduced between Mo and Sb_(2)Se_(3),which can further optimize the growth of Sb_(2)Se_(3)thin ***,positive Na ion diffusion enables it to dramatically lower barrier height at the back contact interface and passivate harmful defects at both bulk and *** a result,the champion substrate structured Mo-foil/Mo/NaF/Sb_(2)Se_(3)/CdS/ITO/Ag flexible thin-film solar cell delivers an obviously higher efficiency of 8.03% and a record open-circuit voltage(V_(OC)) of 0.492 *** flexible Sb_(2)Se_(3) device also exhibits excellent stability and flexibility to stand large bending radius and multiple bending times,as well as superior weak light photo-response with derived efficiency of 12.60%.This work presents an effective strategy to enhance the flexible Sb_(2)Se_(3) device performance and expand its potential photovoltaic applications.

关键词： Sb_(2)Se_(3) Flexible solar cells NaF intermediate layer Interface optimization Defects suppression