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Optimized parameters of downhole all-metal PDM based on genetic algorithm

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Petroleum Science 2024年第4期21卷 2663-2676页

作者： Jia-Xing Lu Ling-Rong Kong yu Wang chao Feng yu-Lin gao China University of Geosciences (Beijing) Key Laboratory on Deep Geo-Drilling Technology of Ministry of Natural Resources

Currently, deep drilling operates under extreme conditions of high temperature and high pressure,demanding more from subterranean power motors. The all-metal positive displacement motor, known for its robust performance, is a critical choice for such drilling. The dimensions of the PDM are crucial for its performance output. To enhance this, optimization of the motor's profile using a genetic algorithm has been undertaken. The design process begins with the computation of the initial stator and rotor curves based on the equations for a screw cycloid. These curves are then refined using the least squares method for a precise fit. Following this, the PDM's mathematical model is optimized, and motor friction is assessed. The genetic algorithm process involves encoding variations and managing crossovers to optimize objective functions, including the isometric radius coefficient, eccentricity distance parameter,overflow area, and maximum slip speed. This optimization yields the ideal profile parameters that enhance the motor's output. Comparative analyses of the initial and optimized output characteristics were conducted, focusing on the effects of the isometric radius coefficient and overflow area on the motor's performance. Results indicate that the optimized motor's overflow area increased by 6.9%, while its rotational speed reduced by 6.58%. The torque, as tested by Infocus, saw substantial improvements of38.8%. This optimization provides a theoretical foundation for improving the output characteristics of allmetal PDMs and supports the ongoing development and research of PDM technology.

关键词： Positive displacement motor Genetic algorithm Profile optimization Matlab programming Overflow area

Highly reversible Zn anode enabled by anticatalytic carbon layer with suppressed hydrogen evolution

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Rare Metals 2024年第7期43卷 3044-3054页

作者： Wen-Duo Zhang Chuang Sun yu-Xuan Zhu Feng gao chao Lai School of Chemistry and Materials Science Jiangsu Normal UniversityXuzhou221116China

Aqueous zinc-ion batteries(AZIBs)have emerged as a promising high-efficiency energy storage system due to the high energy density,low-cost and environmental ***,the practical application of AZIBs is severely restricted by the challenges faced by the Zn anode,which include uncontrollable dendrite growth,corrosion and hydrogen evolution ***,a simple and convenient physical vapor deposition(PVD)method is reported for fabricating uniform graphite as a protection layer on the surface of Zn *** high conductivity graphite layer on Zn anode(denoted as Zn@C)not only benefits the uniform distribution of the electric field,but also provides numerous Zn nucleation sites to regulate and navigate Zn-ion stripping/plating ***,the graphite layer with a poor catalytic activity endows the Zn@C anode with a highly suppressed hydrogen ***,a hydrogen and dendrite free anode is achieved with artificial anticatalytic carbon layer on Zn anode,exhibiting a high reversibility and excellent cycling stability over 2600 h at the current density of 5 mA·cm^(-2)with a capacity of 2.5 mAh·cm^(-2)and longtime cycling stability for assembled full *** work strategically designs the properties of the artificial interface layer to effectively address various challenges simultaneously,which presents insights for the future development of high-performance rechargeable AZIBs.

关键词： Zn metal anode Artificial anticatalytic layer Hydrogen suppression Dendrite free

Spatial diversion and coordination of flood water for an urban flood control project in Suzhou, China

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Water Science and Engineering 2024年第2期17卷 108-117页

作者： yu Xu You-peng Xu Qiang Wang yue-feng Wang chao gao Department of Geography and Spatial Information Techniques Ningbo UniversityNingbo 315211China State Key Laboratoryof Hydology Water Resources and Hydraulic Enginering Nanjing Hydraulic Research InstitueNanjing 210029China Laboratory of Sustainable Urban Drainage Ningbo UniversityNingbo 31521lChina Schol of Gegraphical and Oceanographic Sciences Nanjing UniversiyNanjing 210023China School of Geography and Tourism Chongqing Normal UniversityChongqing 401331China

Suzhou City,located in the Yangtze River Delta in China,is prone to flooding due to a complex combination of natural factors,including its monsoon climate,low elevation,and tidally influenced position,as well as intensive human *** Large Encirclement Flood Control Project(LEFCP)was launched to cope with serious floods in the urban *** project changed the spatiotemporal pattern of flood processes and caused spatial diversion of floods from the urban area to the outskirts of the ***,this study developed a distributed flood simulation model in order to understand this transition of flood *** results revealed that the LEFCP effectively protected the urban areas from floods,but the present scheduling schemes resulted in the spatial diversion of floods to the outskirts of the *** rainstorm frequencies of 10.0%to 0.5%,the water level differences between two representative water level stations(Miduqiao(MDQ)and Fengqiao(FQ))located inside and outside the LEFCP area,ranged from 0.75 m to 0.24 m and from 1.80 m to 1.58 m,*** addition,the flood safety margin at MDQ and the duration with the water level exceeding the warning water level at FQ ranged from 0.95 m to 0.43 m and from 4 h to 22 h,*** scheduling schemes for the hydraulic facilities of the LEFCP in extreme precipitation cases were developed ac-cording to food simulations under seven scheduling *** helps to regulate the spatial flood diversion caused by the LEFCP during extreme precipitation.

关键词： Urban flooding Urban flood control project Rainstorm fregue ncy Flood simulation model Suzhou City

Device design principles and bioelectronic applications for flexible organic electrochemical transistors

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International Journal of Extreme Manufacturing 2024年第1期6卷 126-153页

作者： Lin gao Mengge Wu Xinge yu Junsheng yu State Key Laboratory of Electronic Thin Films and Integrated Devices School of Optoelectronic Science and EngineeringUniversity of Electronic Science and Technology of China(UESTC)Chengdu 610054People’s Republic of China Department of Biomedical Engineering City University of Hong KongHong Kong Special Administrative Region of ChinaPeople’s Republic of China

Organic electrochemical transistors(OECTs) exhibit significant potential for applications in healthcare and human-machine interfaces, due to their tunable synthesis, facile deposition, and excellent biocompatibility. Expanding OECTs to the fexible devices will significantly facilitate stable contact with the skin and enable more possible bioelectronic applications. In this work,we summarize the device physics of fexible OECTs, aiming to offer a foundational understanding and guidelines for material selection and device architecture. Particular attention is paid to the advanced manufacturing approaches, including photolithography and printing techniques, which establish a robust foundation for the commercialization and large-scale fabrication. And abundantly demonstrated examples ranging from biosensors, artificial synapses/neurons, to bioinspired nervous systems are summarized to highlight the considerable prospects of smart healthcare. In the end, the challenges and opportunities are proposed for fexible OECTs. The purpose of this review is not only to elaborate on the basic design principles of fexible OECTs, but also to act as a roadmap for further exploration of wearable OECTs in advanced bio-applications.

关键词： flexible organic electrochemical transistors wearable bioelectronics manufacturing approaches device physics neuromorphic applications

Spatial distribution of supra-permafrost groundwater in the Qinghai-Tibet Engineering Corridor using inversion models

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Advances in Climate Change Research 2024年第1期15卷 31-41页

作者： yu gao Ming-Tang CHAI Wei MA yu-Tao gao State Key Laboratory of Frozen Soils Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 73000China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China School of Civil and Hydraulic Engineering Ningxia UniversityYinchuan 750021China

Supra-permafrost groundwater(SPG)is a key factor that causes damage to highways and railways in the Qinghai-Tibet Engineering Corridor(QTEC).It is difficult to monitor SPG in the field due to their complex formation mechanisms and movement *** single-site field monitoring studies limit the spatial and temporal precision of SPG spatial *** determine the moisture content of shallow soils and the SPG distribution along the QTEC,this work employed the temperature vegetation dryness index and remote sensing models for groundwater table distribution *** accuracies of the models were validated using mea-surements obtained from different sites in the *** the permafrost zones of the QTEC,72%,22%and 6%of the SPG were located at depths of 0.5-1,1 m,***,79.4%of the area along the Qinghai-Tibet Highway(QTH)(Xidatan-Tanggula)section contained *** these sections with SPG,37.9%have an SPG table at depths of 0.5-0.8 *** study preliminarily explored the SPG distribution in the QTEC with a 30 m *** findings can help improve the spatial scale of SPG research,provide a basis for the analysis of the hydrothermal mechanisms,and serve as a guide in the assessment of operational risks and road structure designs.

关键词： Dryness index Landsat Soil moisture Groundwater level Qinghai-Tibet Engineering Corridor

Xuebijing improves intestinal microcirculation dysfunction in septic rats by regulating the VEGF-A/PI3K/Akt signaling pathway

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World Journal of Emergency Medicine 2024年第3期15卷 206-213页

作者： A-ling Tang Yan Li Li-chao Sun Xiao-yu Liu Nan gao Sheng-tao Yan Guo-qiang Zhang Department of Emergency China-Japan Friendship HospitalBeijing 100029China Graduate School Beijing University of Chinese MedicineBeijing 100105China

BACKGROUND:This study aims to explore whether Xuebijing(XBJ) can improve intestinal microcirculation dysfunction in sepsis and its ***:A rat model of sepsis was established by cecal ligation and puncture(CLP).A total of 30 male SD rats were divided into four groups:sham group,CLP group,XBJ + axitinib group,and XBJ *** was intraperitoneally injected 2 h before *** data(blood pressure and heart rate) were *** intestinal microcirculation data of the rats were analyzed via microcirculation ***-linked immunosorbent assay(ELISA) kits were used to detect the serum levels of interleukin-6(IL-6),C-reactive protein(CRP),and tumor necrosis factor-α(TNF-α) in the *** analysis and transmission electron microscopy were used to analyze the injury of small intestinal microvascular endothelial cells and small intestinal mucosa in *** expression of vascular endothelial growth factor A(VEGF-A),phosphoinositide 3-kinase(PI3K),phosphorylated PI3K(p-PI3K),protein kinase B(Akt),and phosphorylated Akt(p-Akt) in the small intestine was analyzed via Western ***:XBJ improved intestinal microcirculation dysfunction in septic rats,alleviated the injury of small intestinal microvascular endothelial cells and small intestinal mucosa,and reduced the systemic inflammatory ***,XBJ upregulated the expression of VEGF-A,p-PI3K/total PI3K,and p-Akt/total Akt in the rat small ***:XBJ may improve intestinal microcirculation dysfunction in septic rats possibly through the VEGF-A/PI3K/Akt signaling pathway.

关键词： Sepsis Xuebijing Vascular endothelial growth factor A Microcirculation Rat Phosphoinositide 3-kinase Protein kinase B

Hybrid pedestrian positioning system using wearable inertial sensors and ultrasonic ranging

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Defence Technology（防务技术） 2024年第3期33卷 327-338页

作者： Lin Qi yu Liu Chuanshun gao Tao Feng yue yu School of Communication and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China Department of Land Surveying and Geo-Informatics The Hong Kong Polytechnic UniversityHong Kong 999077China

Pedestrian positioning system(PPS)using wearable inertial sensors has wide applications towards various emerging fields such as smart healthcare,emergency rescue,soldier positioning,*** performance of traditional PPS is limited by the cumulative error of inertial sensors,complex motion modes of pedestrians,and the low robustness of the multi-sensor collaboration *** paper presents a hybrid pedestrian positioning system using the combination of wearable inertial sensors and ultrasonic ranging(H-PPS).A robust two nodes integration structure is developed to adaptively combine the motion data acquired from the single waist-mounted and foot-mounted node,and enhanced by a novel ellipsoid constraint *** addition,a deep-learning-based walking speed estimator is proposed by considering all the motion features provided by different nodes,which effectively reduces the cumulative error originating from inertial ***,a comprehensive data and model dual-driven model is presented to effectively combine the motion data provided by different sensor nodes and walking speed estimator,and multi-level constraints are extracted to further improve the performance of the overall *** results indicate that the proposed H-PPS significantly improves the performance of the single PPS and outperforms existing algorithms in accuracy index under complex indoor scenarios.

关键词： Pedestrian positioning system Wearable inertial sensors Ultrasonic ranging Deep-learning Data and model dual-driven

Experimental observations on the nonproportional multiaxial ratchetting of cast AZ91 magnesium alloy at room temperature

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 1115-1125页

作者： Binghui Hu yu Lei Hang Li Ziyi Wang chao yu Guozheng Kang Applied Mechanics and Structure Safety Key Laboratory of Sichuan Province School of Mechanics and Aerospace EngineeringSouthwest Jiaotong UniversityChengdu 610031China

The nonproportional multiaxial ratchetting of cast AZ91 magnesium (Mg) alloy was examined by performing a sequence of axial-torsional cyclic tests controlled by stress with various loading paths at room temperature (RT).The evolutionary characteristics and path dependence of multiaxial ratchetting were *** illustrate that the cast AZ91 Mg alloy exhibits considerable nonproportional additional softening during cyclic loading with multiple nonproportional multiaxial loading paths;multiaxial ratchetting presents strong path dependence,and axial ratchetting strains are larger under nonproportional loading paths than under uniaxial and proportional45°linear loading paths;multiaxial ratchetting becomes increasingly pronounced as the applied stress amplitude and axial mean stress ***,stress-strain curves show a convex and symmetrical shape in axial/torsional *** ratchetting exhibits quasi-shakedown after certain loading *** abundant experimental data obtained in this work can be used to develop a cyclic plasticity model of cast Mg alloys.

关键词： cast magnesium alloy ratchetting multiaxial loading loading path stress level

How plants sense and respond to osmotic stress

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Journal of Integrative Plant Biology 2024年第3期66卷 394-423页

作者： Bo yu Dai-Yin chao Yang Zhao Shanghai Center for Plant Stress Biology CAS Center for Excellence in Molecular Plant SciencesThe Chinese Academy of SciencesShanghai 200032China Key Laboratory of Plant Carbon Capture The Chinese Academy of SciencesShanghai 200032China National Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant SciencesInstitute of Plant Physiology and EcologyThe Chinese Academy of SciencesShanghai 200032China University of Chinese Academy of Sciences Beijing 100049China

Drought is one of the most serious abiotic stresses to land *** sense and respond to drought stress to survive under water *** have studied how plants sense drought stress,or osmotic stress caused by drought,ever since Charles Darwin,and gradually obtained clues about osmotic stress sensing and signaling in *** stress is a physical stimulus that triggers many physiological changes at the cellular level,including changes in turgor,cell wall stiffness and integrity,membrane tension,and cell fluid volume,and plants may sense some of these stimuli and trigger downstream *** this review,we emphasized water potential and movements in organisms,compared putative signal inputs in cell wall-containing and cell wall-free organisms,prospected how plants sense changes in turgor,membrane tension,and cell fluid volume under osmotic stress according to advances in plants,animals,yeasts,and bacteria,summarized multilevel biochemical and physiological signal outputs,such as plasma membrane nanodomain formation,membrane water permeability,root hydrotropism,root halotropism,Casparian strip and suberin lamellae,and finally proposed a hypothesis that osmotic stress responses are likely to be a cocktail of signaling mediated by multiple *** also discussed the core scientific questions,provided perspective about the future directions in this field,and highlighted the importance of robust and smart root systems and efficient source-sink allocations for generating future high-yield stress-resistant crops and plants.

关键词： cell volume drought membrane tension osmotic stress turgor