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

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

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Which Neighborhoods Have Easier Access to Online Home Delivery Services?A Spatiotemporal Accessibility Analysis in Nanjing,China

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Chinese Geographical Science 2024年第4期34卷 722-738页

作者： KONG yu ZHEN feng ZHANG Shanqi SHEN Lizhen School of Architecture and Urban Planning Nanjing UniversityNanjing 210093China Provincial Engineering Research Center of Smart City Planning and Digital Governance Nanjing 210093China

The rise in online home delivery services(OHDS)has had a significant impact on how urban services are supplied and used in recent *** on the spatial accessibility of OHDS are emerging,but few is known about the temporal dimension of OHDS accessibility as well as the geographic and socioeconomic differences in the spatiotemporal accessibility of *** study measures the spatiotemporal accessibility of four types of OHDS,namely leisure,fresh and convenient,medical,and catering *** geographic and socioeconomic disparities in the spatiotemporal accessibility of these four types of OHDS are then identified using spatial statistical methods and the Kruskal-Wallis test(K-W test).The case study in Nanjing,China,suggests that:1)spatiotemporal accessibility better reflects the temporal variation of OHDS accessibility and avoids overestimation of OHDS accessibility when only considering its spatial dimension.2)The spatiotemporal accessibility of OHDS varies geographically and *** located in the main city or neighborhoods with higher housing prices,higher population density,and higher point of interest(POI)mix have better OHDS spatiotemporal *** study contributes to the understanding of OHDS accessibility from a spatiotemporal perspective,and the empirical insights can assist policymakers in creating intervention plans that take into account variations in OHDS spatiotemporal accessibility.

关键词： online home delivery services(OHDS) spatiotemporal accessibility neighborhoods accessibility differences Nanjing City China

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Machine learning in metal-ion battery research: Advancing material prediction, characterization, and status evaluation

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Journal of Energy Chemistry 2024年第3期90卷 191-204,I0006页

作者： Tong yu Chunyang Wang Huicong Yang feng Li Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016LiaoningChina School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016LiaoningChina Department of Physics and Astronomy University of California IrvineIrvineCA92697USA

Metal-ion batteries(MIBs),including alkali metal-ion(Li^(+),Na^(+),and K^(3)),multi-valent metal-ion(Zn^(2+),Mg^(2+),and Al^(3+)),metal-air,and metal-sulfur batteries,play an indispensable role in electrochemical energy ***,the performance of MIBs is significantly influenced by numerous variables,resulting in multi-dimensional and long-term challenges in the field of battery research and performance *** learning(ML),with its capability to solve intricate tasks and perform robust data processing,is now catalyzing a revolutionary transformation in the development of MIB materials and *** this review,we summarize the utilization of ML algorithms that have expedited research on MIBs over the past five *** present an extensive overview of existing algorithms,elucidating their details,advantages,and limitations in various applications,which encompass electrode screening,material property prediction,electrolyte formulation design,electrode material characterization,manufacturing parameter optimization,and real-time battery status ***,we propose potential solutions and future directions for the application of ML in advancing MIB development.

关键词： Metal-ion battery Machine learning Electrode materials Characterization Status evaluation

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Alignment of Track Oscillations during Tropical Cyclone Rapid Intensification

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Advances in Atmospheric Sciences 2024年第4期41卷 655-670页

作者： Tong XIE Liguang WU Yecheng feng Jinghua yu Key Laboratory of Meteorological Disaster of Ministry of Education Nanjing University of Information Science and TechnologyNanjing 210044China Dept.of Atmospheric and Oceanic Sciences and Institute of Atmospheric Sciences Fudan UniversityShanghai 200438China CMA-FDU Joint Laboratory of Marine Meteorology Shanghai 200438China

Recent studies on tropical cyclone(TC)intensity change indicate that the development of a vertically aligned TC circulation is a key feature of its rapid intensification(RI),however,understanding how vortex alignment occurs remains a challenging topic in TC intensity change *** on the simulation outputs of North Atlantic Hurricane Wilma(2005)and western North Pacific Typhoon Rammasun(2014),vortex track oscillations at different vertical levels and their associated role in vortex alignment are examined to improve our understanding of the vortex alignment during RI of TCs with initial hurricane *** is found that vortex tracks at different vertical levels oscillate consistently in speed and direction during the RI of the two simulated *** the consistent track oscillation reduces the oscillation tilt during RI,the reduction of vortex tilt results mainly from the mean track before *** is also found that the vortex tilt is primarily due to the mean vortex track before and after *** track oscillations are closely associated with wavenumber-1 vortex Rossby waves that are dominant wavenumber-1 circulations in the TC inner-core *** study suggests that the dynamics of the wavenumber-1 vortex Rossby waves play an important role in the regulation of the physical processes associated with the track oscillation and vertical alignment of TCs.

关键词： tropical cyclone rapid intensification vortex tilt Rossby wave

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Chronic sleep deprivation induces alterations in DNA and RNA modifications by liquid chromatography-mass spectrometry analysis

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Chinese Chemical Letters 2024年第8期35卷 413-417页

作者： Tian feng yun-Ling Gao Di Hu Ke-yu yuan Shu-Yi Gu Yao-Hua Gu Si-yu yu Jun Xiong yu-Qi feng Jie Wang Bi-feng yuan School of Public Health Research Center of Public HealthRenmin Hospital of Wuhan UniversityWuhan UniversityWuhan 430071China Department of Radiation and Medical Oncology Zhongnan Hospital of Wuhan UniversityWuhan UniversityWuhan 430071China Key Laboratory of Magnetic Resonance in Biological Systems State Key Laboratory of Magnetic Resonance and Atomic and Molecular PhysicsNational Center for Magnetic Resonance in WuhanWuhan Institute of Physics and MathematicsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of Sciences-Wuhan National Laboratory for OptoelectronicsWuhan 430071China University of Chinese Academy of Sciences Beijing 101408China Institute of Neuroscience and Brain Diseases Xiangyang Central HospitalAffiliated Hospital of Hubei University of Arts and ScienceXiangyang 441000China Phase I Clinical Trial Laboratory Zhongnan Hospital of Wuhan UniversityWuhan 430071China

Sleep deprivation(SD)is a widespread issue that disrupts the lives of millions of *** effects ini-tiate as changes within neurons,specifically at the DNA and RNA level,leading to disruptions in neuronal plasticity and the dysregulation of various cognitive functions,such as learning and *** acid epigenetic modifications that could regulate gene expression have been reported to play crucial roles in this ***,there is a lack of comprehensive research on the correlation of SD with nucleic acid epigenetic *** the current study,we aimed to systematically investigate the landscape of modifications in DNA as well as in small RNA molecules across multiple tissues,including the heart,liver,kidney,lung,hippocampus,and spleen,in response to chronic sleep deprivation(CSD).Using liquid chromatography-tandem mass spectrometry(LC-MS/MS)analysis,we characterized the dynamic changes in DNA and RNA modification profiles in different tissues of mice under CSD ***,we ob-served a significant decrease in the level of 5-methylcytosine(5mC)and a significant increase in the level of 5-hydroxymethylcytosine(5hmC)in the kidney in CSD *** RNA modifications,we observed an overall increased trend for most of these significantly changed modifications across six tis-sues in CSD *** study sheds light on the significance of DNA and RNA modifications as crucial epigenetic markers in the context of CSD-induced stress.

关键词： Sleep deprivation Epigenetics Mass spectrometry DNA modification RNA modification Small RNA

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Discovery of TK-642 as a highly potent,selective,orally bioavailable pyrazolopyrazine-based allosteric SHP2 inhibitor

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Acta Pharmaceutica Sinica B 2024年第8期14卷 3624-3642页

作者： Kai Tang Shu Wang Siqi feng Xinyu Yang yueyang Guo Xiangli Ren Linyue Bai Bin yu Hong-Min Liu Yihui song School of Pharmaceutical Sciences&Key Laboratory of Advanced Drug Preparation Technologies Ministry of EducationZhengzhou UniversityZhengzhou 450001China College of Chemistry Pingyuan LaboratoryState Key Laboratory of Antiviral DrugsZhengzhou UniversityZhengzhou 450001China Tianjian Laboratory of Advanced Biomedical Sciences Institute of Advanced Biomedical SciencesZhengzhou UniversityZhengzhou 450000China State Key Laboratory of Pharmaceutical Biotechnology Nanjing UniversityNanjing 210023China

Src homology-2-containing protein tyrosine phosphatase 2(SHP2)is a promising therapeutic target for cancer *** this work,we presented the structure-guided design of 5,6-fused bicyclic allosteric SHP2 inhibitors,leading to the identification of pyrazolopyrazine-based TK-642 as a highly potent,selective,orally bioavailable allosteric SHP2 inhibitor(SHP2WT IC_(50)=2.7 nmol/L)with favorable pharmacokinetic profiles(F=42.5%;t_(1/2)=2.47 h).Both dual inhibition biochemical assay and docking analysis indicated that TK-642 likely bound to the“tunnel”allosteric site of ***-642 could effectively suppress cell proliferation(KYSE-520 cells IC_(50)=5.73μmol/L)and induce apoptosis in esophageal cancer cells by targeting the SHP2-mediated AKT and ERK signaling ***,oral administration of TK-642 also demonstrated effective anti-tumor effects in the KYSE-520 xenograft mouse model,with a T/C value of 83.69%.Collectively,TK-642 may warrant further investigation as a promising lead compound for the treatment of esophageal cancer.

关键词： Protein tyrosine phosphatase Pyrazolopyrazine SHP2 inhibitor Esophageal cancer

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Light weight design and integrated method for manufacturing hydraulic wheel-legged robots

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第9期25卷 701-715页

作者： Xu LI Haoyang yu Huaizhi ZONG Haibo feng Yili FU State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310058China

Design and manufacturing play pivotal roles in hydraulic-driven robotic ***,previous studies have emphasized mainly results and performance,often overlooking the specifics of the design and manufacturing *** paper introduces a novel approach known as light weight design and integrated manufacturing(LD&IM)for hydraulic wheel-legged *** LD&IM method leverages topology optimization and generative design techniques to achieve a substantial 45%weight reduction,enhancing the robot’s dynamic motion *** innovative design method not only streamlines the design process but also upholds the crucial attributes of light weight construction and high strength essential for hydraulic wheel-legged ***,the integrated manufacturing method,incorporating selective laser melting(SLM)and high-precision subtractive manufacturing(SM)processes,expedites the fabrication of high-quality *** the LD&IM approach,a hydraulic-driven single wheel-legged robot,denoted as WLR-IV,has been successfully *** robot boasts low mass and inertia,high strength,and a simplified component *** assess its dynamic jumping capabilities,the control loop integrates a linear quadratic regulator(LQR)and zero dynamic-based controller,while trajectory planning uses the spring-loaded inverted pendulum(SLIP)*** jumping results confirm the WLR-IV single-legged robot’s exceptional dynamic performance,validating both the effectiveness of the LD&IM method and the rationale behind the control strategy.

关键词： Wheel-legged robot Hydraulic driven Topology optimization Wheel-legged robot Hydraulic driven Topology optimization Additive manufacturing(AM) Jump control

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Cu,N codoped carbon nanosheets encapsulating ultrasmall Cu nanoparticles for enhancing selective 1,2-propanediol oxidation

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Journal of Energy Chemistry 2024年第4期91卷 27-35页

作者： Yonghai feng Min yu Minjia Meng Lei Liu Dewei Rao Institute for Advanced Materials School of Materials Science and EngineeringJiangsu UniversityZhenjiang 212013JiangsuChina School of Chemistry and Chemical Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

In the selective oxidation of biomass-based 1,2-propanediol(PDO)with oxygen as the terminal oxidant,it is challenging to improve the lactic acid(LA)selectivity for nonnoble metal nanoparticles(NPs)due to their limited oxygen reduction rate and easy C-C *** the high economic feasibility of nonnoble metals,i.e.,Cu,in this work,copper and nitrogen codoped porous carbon nanosheets encapsulating ultrafine Cu nanoparticles(Cu@Cu-N-C)were developed to realize highly selective of PDO oxidation to *** carbon-encapsulated ultrasmall Cu^(0)NPs in Cu@Cu-N-C have high PDO dehydrogenation activity while N-coordinated Cu(Cu-N)sites are responsible for the high oxygen reduction ***,the performance of catalytic PDO conversion to LA is optimized by a proposed pathway of PDO→hydroxylacetone→lactaldehyde→***,the enhanced LA selectivity is 88.5%,and the PDO conversion is up to 75.1%in an O_(2)-pressurized reaction system(1.0 MPa O_(2)),superior to other Cu-based catalysts,while in a milder nonpressurized system(O_(2)flow rate of 100 mL min-1),a remarkable LA selectivity(94.2%)is obtained with 39.8%PDO conversion,2.2 times higher than that of supported Au nanoparticles(1%Au/C).Moreover,carbon encapsulation offers Cu@Cu-N-C with strong leaching resistance for better recycling.

关键词： Selective oxidation Copper and nitrogen doped carbon 1,2-Propanediol Ultrasmall Cu nanoparticles Lactic acid

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Low carbon alcohol fuel electrolysis of hydrogen generation catalyzed by a novel and effective Pt–CoTe/C bifunctional catalyst system

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Green Energy & Environment 2024年第4期9卷 758-770页

作者： Yang Zhou Lice yu Jinfa Chang Ligang feng Jiujun Zhang School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou225002JiangsuChina NanoScience Technology Center University of Central FloridaOrlandoFL32826USA College of Sciences&Institute for Sustainable Energy Shanghai UniversityShanghai200444China

Low carbon alcohol fuels electrolysis under ambient conditions is promising for green hydrogen generation instead of the traditional alcohol fuels steam reforming technique,and highly efficient bifunctional catalysts for membrane electrode fabrication are required to drive the electrolysis ***,the efficient catalytic promotion effect of a novel catalyst promoter,CoTe,on Pt is demonstrated for low carbon alcohol fuels of methanol and ethanol electrolysis for hydrogen *** and density functional theory calculation results indicate that the optimized electronic structure of Pt–CoTe/C resulting from the synergetic effect between Pt and CoTe further regulates the adsorption energies of CO and H*that enhances the catalytic ability for methanol and ethanol ***,the good water activation ability of CoTe and the strong electronic effect of Pt and CoTe increased the tolerance ability to the poisoning species as demonstrated by the CO-stripping *** high catalytic kinetics and stability,as well as the promotion effect,were also carefully ***,71.9%and 75.5%of the initial peak current density was maintained after 1000 CV cycles in acid electrolyte for methanol and ethanol oxidation;and a low overpotential of 30 and 35 mV was required to drive the hydrogen evolution reaction in methanol and ethanol solution at the current density of 10 mA cm^(-2).In the two-electrode system for alcohol fuels electrolysis,using the optimal Pt–CoTe/C catalyst as bi-functional catalysts,the cell potential of 0.66 V(0.67 V)was required to achieve 10 mA cm^(-2) for methanol(ethanol)electrolysis,much smaller than that of water electrolysis(1.76 V).The current study offers a novel platform for hydrogen generation via low carbon alcohol fuel electrolysis,and the result is helpful to the catalysis mechanism understanding of Pt assisted by the novel promoter.

关键词： Methanol electrolysis Ethanol electrolysis Cobalt telluride Pt-based electrocatalyst Hydrogen evolution reaction

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Flexible pressure sensors with ultrahigh stress tolerance enabled by periodic microslits

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Microsystems & Nanoengineering 2024年第1期10卷 301-311页

作者： song Wang Chenying Wang Yifan Zhao yujing Zhang Yaxin Zhang Xiangyue Xu Qijing Lin Kai Yao yuheng Wang feng Han yu Sun Zhuangde Jiang State Key Laboratory for Manufacturing Systems Engineering International Joint Laboratory for Micro/Nano Manufacturing and Measurement TechnologiesSchool of Mechanical EngineeringXi’an Jiaotong UniversityXi’anChina State Key Laboratory for Manufacturing Systems Engineering International Joint Laboratory for Micro/Nano Manufacturing and Measurement TechnologiesSchool of Instrument Science and TechnologyXi’an Jiaotong UniversityXi’anChina The Faculty of Electrical Engineering and Computer Science Ningbo UniversityNingboChina Department of Mechanical and Industrial Engineering University of TorontoTorontoCanada

Stress tolerance plays a vital role in ensuring the effectiveness of piezoresistive sensing films used in flexible pressure ***,existing methods for enhancing stress tolerance employ dome-shaped,wrinkle-shaped,and pyramidal-shaped microstructures in intricate molding and demolding processes,which introduce significant fabrication challenges and limit the sensing *** address these shortcomings,this paper presents periodic microslits in a sensing film made of multiwalled carbon nanotubes and polydimethylsiloxane to realize ultrahigh stress tolerance with a theoretical maximum of 2.477 MPa and a sensitivity of 18.092 kPa−*** periodic microslits permit extensive deformation under high pressure(e.g.,400 kPa)to widen the detection ***,the periodic microslits also enhance the sensitivity based on simultaneously exhibiting multiple synapses within the sensing interface and between the periodic sensing *** proposed solution is verified by experiments using sensors based on the microslit strategy for wind direction detection,robot movement sensing,and human health *** these experiments,vehicle load detection is achieved for ultrahigh pressure sensing under an ultrahigh pressure of over 400 kPa and a ratio of the contact area to the total area of 32.74%.The results indicate that the proposed microslit strategy can achieve ultrahigh stress tolerance while simplifying the fabrication complexity of preparing microstructure sensing films.

关键词： robot shaped stress

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